Department of Life Sciences

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    Comprehensive morphological and molecular analyses of flowering events in Bambusa tulda
    Das, Malay
    Flowering is one of the most important adaptations in the history of plant evolution. Our current understanding of flowering and the genes involved in the regulation of flowering time are based on the studies conducted on the model plants Arabidopsis thaliana and Oryza sativa. Since both these plants are annual and herbaceous, it is unlikely that the information obtained from these studies can directly be translated to explain the unusually extended flowering time in bamboo. The ecological impacts caused due to bamboo flowering are known for decades, but our knowledge about flower development and also the genes controlling such unique flowering behaviour is very inadequate in bamboo. a major objective of this study was to understand the detailed reproductive features of B. tulda Roxb. by studying the morphological (inflorescence, flower and pollen), histological (inflorescence) and biochemical (pollen viability) analyses. This study observed that protrandry, limited pollen liberation, low pollen viability and low seed setting are prevalent in B. tulda. Another major objective of this study was to characterize important flower induction and pathway integrator genes in order to understand their role in flower induction in tropical bamboos. Four copies of FLOWERING LOCUS T (BtFT1, BtFT2, BtFT3 and BtFT4) and two copies of FD (BtFD1, BtFD2) genes were identified and their tissue-specific as well as diurnal gene expression analyses revealed possible functional divergence among the closely related homologs. Taken together, this study indicates that copy number expansion and expression divergence may lead to new regulation of flowering gene functions in bamboo.
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    Studies on Ecology of Soft-Bottom Meiobenthic Community from Sundarban Estuarine System, West Bengal, India
    Mandal, Sumit
    Structure of meiobenthic assemblage was assessed for the first time from world’s largest mangrove ecosystem, Sundarbans, focusing on free living nematode species composition (~ 90% of the total population). The present research revealed the deleterious effect of excessive monsoonal rain on meiobenthos as well as free-living nematode assemblages. Abundance of meiobenthos declined from early monsoon to later period of monsoon due to massive riverine runoff followed by cloudburst phenomenon that completely flushed the estuary. Significant temporal and spatial heterogeneity in the abundance of meiobenthos and nematode species composition was also described in relation with environmental variables. Distinct seasonal fluctuation of meiobenthos was prominent due to seasonal changes in sedimentary environment. Nematodes dominated the meiobenthic assemblages, ranking harpacticoid copepod in the second position. Altogether, 79 species of free-living nematode had been identified for the first time and nematode assemblage was dominated by Sabatieria preadatrix, Sphaerolaimus bulticus, Desmodora communis, Dorylaimopsis punctata and Daptonema hirsutum. Biological trait approach of nematode assemblages was applied to investigate the ecological functioning based on morphological and ecological characteristics, which added relevant information regarding relationships between species diversity and the abiotic environment. Furthermore, present study conducted a pioneering survey regarding vertical stratification of meiobenthic assemblages in different mangrove vegetation with nematofaunal species level information. This study clearly depicted that more than 90% of faunal populations was concentrated within upper 3-4 cm of sediment, though they were present up to 15 cm of depth. Furthermore, combined effect of climate change mediated elevated temperature and petroleum pollution on meiobenthic organisms were also investigated through a benthocosm experiment. The present research highlighted harmful effects of these stressors on meiobenthic species composition and abundance. Present observation would be a maiden footstep to understand the resilience of meiobenthic organisms to predicted climate change scenarios. Altogether the present thesis provided blended information about the succession pattern of meiobenthic community structure along with environmental parameters and illustrated the detrimental effect of climate change and anthropogenic perturbation on meiobenthos from Sundarbans. This overview represents a first step to implement a baseline data that could help identifying information gaps and directing future research priorities simultaneously.
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    Quantification of oxidative stress and physiological parameters due to schoolbag carriage in normal, overweight/obese male schoolchildren of West Bengal
    Mukhopadhyay, Aparna
    Background: The physical activity of schoolbag carriage is a form of mandatory load carriage with a myriad of physiological consequences, the most common being pain occurrence and changes in physiological responses. The cardio-pulmonary response to a physical activity is dependent on its intensity which translates to weight of schoolbag being carried. The response to each physical activity is also dependent on the fat or lean body mass (body composition) of the individual performing it. Response to physical activity in subjects with an abundance of body fat is also concurrent with development of oxidative stress in the body. So, it is hypothesised that schoolbag carriage engenders different physiological response in terms of cardio-pulmonary, pain, postural and oxidative stress response in children belonging to different categories of body mass index (BMI). Methodology: Parental survey about awareness regarding behaviour and practices of their children with respect to schoolbag carriage was assessed by survey sheets. Anthropometric measurements for schoolchildren (males aged 10-15 years, n=60) were recorded and they were categorised into normal and overweight/obese BMI groups. They walked for 20-minutes with backpacks of varying weight (0%, 4%, 8%, 12% and 16% of bodyweight) during which their cardio-pulmonary parameters were assessed via COSMED k4b2. During the walks, pain reports for the entire body were mapped. The walks were video-graphed for analysis of postural undulations. Cognitive ability was assessed by ruler drop test (RDT). Before and after each walk, saliva collection was accomplished via passive drooling and the collected bio-fluid was assayed for biomarkers pertinent to oxidative stress. The parameters studied were evaluated for continuity, distribution and comparison was then further conducted by parametric or non-parametric tests whichever applicable. A mathematical model predicting the percentage change in antioxidant capacity using standardized pain, load of schoolbag carried and BMI as the predictors was developed employing linear regression. Results: Parental reports suggested that children carried heavy schoolbags in general and complained of pain causing high discomfort in neck, shoulder and back region. Majority of the parents never received any recommendations about safe load limits. All recorded anthropometric measurements for the age matched BMI categories were significantly higher (p<0.05) in overweight/obese BMI category compared to the normal category. During schoolbag carriage, heart regulation was better in case of normal BMI individuals. The lung volumes and energy expenditure were higher in overweight/obese participants (p<0.05). Cognition improved in children with normal BMI after carrying lower weight backpacks. The pain perceived was highest in the neck, shoulder and back region with shoulder. Pain perceived was higher in overweight/obese children. Posture worsened over time, and the postural undulations were more deleterious in overweight/obese children. Antioxidant status improved after carrying lower weight schoolbags. Nitric oxide mediated vasodilation was comparable in both BMI groups. The pain perception, load of schoolbag carried and BMI successfully predicted the percentage change in non-enzymatic antioxidant capacity via significant (p<0.05) mathematical regression model. Conclusion: For the same physiological load of schoolbag carried, the overweight/obese children are relatively inefficient in regulating their cardio-pulmonary responses, they suffered from higher cognitive and postural decline besides developing greater oxidative stress compared to their age-matched normal BMI counterparts. The load limit of schoolbag pertaining to 8% and 4% load of bodyweight is recommended for normal BMI and overweight/obese children based on the cumulative results on all parameters studied. The prediction equation developed realises the customized determination of safe load limit in every child. This study can be used by policy makers to formulate schoolbag load limit recommendations keeping in mind the BMI of children thus ameliorating the derogatory effects of carrying heavy schoolbags in children and safeguarding child health.
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    Deciphering micro/nanoplastic induced phytotoxicity with special emphasis on the cytogenotoxic effects on Allium cepa L.
    Pramanick, Kousik
    Considering the present plastic pollution crisis, this thesis work reported the phytotoxicity of polystyrene micro/nanoplastics (M/NPs) in onion with effects on seed germination, root growth, and cytotogenotoxicity. The detection of negative impacts in environmentally relevant concentrations of polystyrenes (PS) clearly showed the harmful effects of polystyrene particles on the plants health, indicating its possible negative impacts on biodiversity. The root growth rather than seed germination was negatively affected by the increasing concentrations of polystyrene particles. The tested diameter of polystyrene particles caused an imbalance in redox homeostasis through the elevated production of ROS, which in high concentrations of polystyrenes subdues the antioxidant defence and ensues in different harmful effects. Different chromosomal alterations and DNA damage potential of micro/nanopolystyrenes (M/NPS), as recorded in this work, may indicate the potential threat of micro/nanoplastics to other organisms because, the basic genetic makeup is same for all eukaryotes. The combined effects of nanoplastics and heavy metals such as Cd and Hg were also evaluated showing an increasing level of toxicity of Cd and a decreasing toxicity of Hg in the presence of polystyrene particles. This observation signifies a differential effect of plastics in modulating the toxicities of heavy metals depending on metal species. Another interesting finding of this work was the positive impact of high temperature or temperature stress (TS), but not the salinity stress (SS), in aggravating the toxicity of micro/nanoplastics. The temperature stress improves the root accumulation of polystyrene particles with notable deleterious effects on oxidative stress, microtubules stability, and organization. In this study, we have used the term micropolystyrene and nanopolystyrene interchangeably for the same diameter (100 nm or 0.1 µm) of polystyrene particles, because the selected diameter remains at the transition between micro and nano particles and there is no accepted distinction on nanoplastics size unlike metal nanoparticles. Some authors have used the term micro for this diameter, while others have used nano for the same.
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    Tbx20 function in Proepicardial organ (PEO) & epicardium derived cell differentiation and Asporin /PLAP-1 function in aortic valve calcification
    Chakraborty, Santanu
    Nowadays, the problem of cardiovascular diseases is a major burden and a leading causes of morbidity and mortality in humans, globally. A proper understanding of the cellular and molecular mechanisms of heart failure has just started to provide better medical care and patient management. It has now become increasingly clear that cardiomyocyte proliferation, cardiac progenitor cell induction, development and differentiation of several cardiac cell lineages and cardiac extracellular matrix (ECM) remodeling are the dynamic processes, critical for injured myocardial repair. Proepicardial organ (PEO) is an extra cardiac villous protrusion at the venous pole of vertebrate embryonic heart that forms epicardium migrating onto the myocardium. PEO-derived epicardium and epicardium derived cells or EPDCs contribute several cardiac cell lineages including smooth muscle cells (SMs), fibroblasts, endothelial cells and cardiomyocytes (CMs). But in the developing heart, detailed gene expression pattern of several lineage specific markers within PEO progenitor cells and its epicardial derivatives are relatively unknown. Cardiomyocyte differentiation from proepicardial organ (PEO) and embryonic epicardium (eEpi) derived cells or EPDCs in developing heart, emerges a wide interest in purview of cardiac repair and regenerative medicine. Embryonic epicardium (eEpi) originates from the precursor PEO and EPDCs and contributes to several cardiac cell types including smooth muscle cells, fibroblasts, endothelial cells and also cardiomyocytes (CMs) during cardiogenesis. Using avian explant culture system, our data have yielded differential expression of several marker genes in PEO versus epicardial cells. Next, to explore the role of Wnt/β-catenin signaling in PEO and EPDCs, avian E5 epicardial cells were treated with lithium chloride (LiCl), recombinant Wnt3a (rhWnt3a) protein and Xav939. Addition of LiCl and rhWnt3a have inhibited glycogen synthase kinase 3β, stabilizing β-catenin and reversely, addition of Xav939 have inhibited Wnt/ β-catenin signaling in avian explant cultures. Interestingly avian epicardial explant cultures, treated with LiCl and rhWnt3a, show increased mRNA expression of Tbx20 concomitant with induced expression of CM lineage markers and Xav939 treated epicardial explant cultures show decreased expression Tbx20 and CM markers. In addition, Wnt signaling activation also increases the number of proliferating and sarcomeric myosin (Mf20) positive cells in eEpi explant culture. Together, these data suggest, eEpi cells as a source for CM differentiation and Wnt signaling mediator, β-catenin might play an important role in CM differentiation from eEpicells in culture. Overall, aim1of this thesis suggests the importance of Tbx20 viii | P a g e and β-catenin in regulation of CM lineage differentiation from EPDCs. Therefore, our studies will further provide a mechanistic insight into the PEO based therapies for CM support improving therapeutic and regenerative approaches following adult cardiac injury. Likewise, valvular diseases, importantly calcific aortic valve diseases (CAVDs) are also projecting serious concerns throughout the world. CAVDs account for 25% of all types of cardiac disease, causing significant number of morbidity and mortality among patients with cardiac abnormalities. Aortic valve mineralization and calcification are the key events of adult calcific aortic valve disease manifestation and functional insufficiency. Due to heavy mineralization and calcification, adult aortic valvular cusps show disorganized and dispersed stratification concomitant with deposition of calcific nodules with severely compromised adult valve function. Interestingly, shared gene regulatory pathways are identified between bone forming cells and heart valve cells during development. Asporin, a small leucine rich proteoglycan, acts to inhibit mineralization in periodontal ligament cells and is also detected in normal murine adult aortic valve leaflets with unknown function. Therefore, to understand the Asporin function in aortic cusp mineralization and calcification, adult avian aortic valvular interstitial cell culture system is established and osteogenesis has been induced in these cells successfully. Upon induction of osteogenesis, reduced expression of Asporin mRNA and increased expression of bone and osteogenesis markers are detected compared to cells maintained without osteogenic induction. Importantly, treatment with human recombinant Asporin protein reduces the mineralization level in osteogenic media induced aortic valvular interstitial cells with the concomitant decreased level of Wnt/β-catenin signaling. Overall, all these data are highly indicative that Asporin might be a novel bio-molecular target to treat patients of calcific aortic valve disease over current cusp replacement surgery. Thus, studies of two aims in cardiovascular research area will enrich and reveal new insights which will enhance the ongoing as well as future investigations in cardiac therapeutic field
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    A multibiomarker study to delineate the effects of environmental stressors on aquatic shellfishes of West Bengal
    Mandal, Sumit
    Over the past decade a great attention has been paid to decipher the consequences of impending climate change scenario on the physiological and biochemical functioning of aquatic organisms. Anthropogenic activities primarily combustion of fossil fuel is the prime cause behind the increased concentration of CO2 into the atmosphere. As a consequence, marine environments are anticipated to experience more shift towards lower pH (ocean acidification) and elevated temperatures (ocean warming). Global climate change induced ocean warming and acidification have complex reverberation on physiological functioning of marine ectotherms. Moreover, since the industrial revolution the growing demand for petroleum-based products has been mounting up worldwide leading to severe oil pollution. Widespread use of pesticides in modern agricultural system has a significant contribution in polluting aquatic habitats across the world; and enclosed freshwater ecosystem being the ultimate receptacle is at great risk. In recent years, application of nanotechnology also has become more widespread and nanomaterials are constantly being released into aquatic environments and posing a potential risk to various organisms and ecosystems. Research works merging climate change stressors and incipient chemical pollutants are imperative to better comprehend and interpret biological effects in altering aquatic habitat. Environmental factors and pollution generally do not act in isolation, but usually perform collectively. Several researches have recognized the discrete effects of these drivers on species and ecosystems separately but studies regarding the interactive effects of multiple drivers are scarce. Animal physiologists have now unambiguously recognized the fact that anticipated climatic vicissitudes will impose noteworthy consequences on physiological functioning of most species. Ectotherms are of specific interest as their physiology principally relies on the external environment. The purpose of present study was to compare and decipher the impacts of multiple stressors and specifically whether global environmental drivers aggravate the effects of a local driver (pollution) on physiological energetics and antioxidant responses of two economically significant shellfishes from West Bengal. Two species from two different ecosystems- freshwater and estuarine were studied to compare and decode the ecological functioning of these realms distinctly. Multiple biomarkers from different levels of biological strata (physiological energetics, energy budget, thermal performance, antioxidant and detoxification defence mechanisms, lipid peroxidation levels, DNA damage) of the species were evaluated to understand responses. Stress levels were amalgamated from individual biomarker responses using an “Integrated Biomarker Response (IBR)” approach. The present doctoral work can provide an outline for more integrated management of commercially exploited shellfish populations, and shed light into coastal fisheries and aquaculture prospects in the impending future.
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    A Study of Antibacterial and Anti-Inflammatory Activity of Zinc Oxide Nanoparticles (ZnONPs) on Multiple Antibiotic-Resistant Staphylococcus Aureus Induced Inflammatory Rat Model
    Sikdar, Mausumi
    Conventional treatment strategies involving antibiotics are gaining accelerated challenges as a result of increasing antibiotic resistance by pathogenic microorganisms. A significant quantity of therapeutic research had been focused on implementing green synthesized nanoparticles. In this study, the green synthesis method has been used to prepare ZnONPs from leaf extract of coriander. The green synthesized and chemically synthesized commercially available ZnONPs showed almost no variation concerning their size and morphology when characterized by methods like XRD, DLS, etc. Comparison of antibacterial potential among both types of ZnONPs, used against strains of (Control and Clinical) reveals, lower MIC and MBC of green ZnONPs were required to generate the same quality of bactericidal effect as achieved by using the commercial one. This signifies that, apart from easy synthesis procedure, lower doses are enough to generate the desired anti-bacterial efficacy. After inducing septic arthritis by clinical strain (KC-02) of S. aureus, both ZnONPs (chemical and green) were capable of lowering the increased serum level of inflammatory markers, without producing the measurable amount of serum oxidative stress. The combination of ZnONPs (both chemical and green) and antibiotics shows excellent antibacterial and anti-inflammatory potential. The part of this study involving the in-vivo model indicates that both the ZnONPs when used in the mentioned concentration alone and also in combination with an antibiotic, are incapable of precipitating histological changes in selected organs like the liver, kidney, spleen, and adrenal gland. Therefore, the use of ZnONPs, a preferably green one for treating inflammatory diseases like septic arthritis, could be a better choice over conventional antibiotic therapy.
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    Apoptosis regulators as targets for induction of apoptosis of Imatinib resistant chronic myeloid leukemia cells
    Biswas, Nabendu
    Apoptosis is a regulated cell death characterized by cell shrinkage, nuclear condensation, DNA fragmentation, membrane blebbing. There are several apoptosis regulators eg: BCL2, Bcl-xL, BAX, Survivin, FLIP, XIAP, cIAP etc. Targeting these apoptosis regulators may be a viable strategy for the treatment of cancer because one of the hallmarks of cancer is the deregulation of apoptosis. In our first study we tried to induce cell death in Imatinib-resistant chronic myelogenous Leukemia cell line K562, by using TRAIL, a well-studied anti-cancer agent. Normally these cells are also resistant to TRAIL. We used Hydroxychavicol, a Piper betel leaf derived polyphenol, to make this Imatinib- resistant K562 cells sensitive to TRAIL. In imatinib resistant K562 cells, XIAP, FLIP have emerged as targets by hydroxychavicol to sensitize the cells to TRAIL mediated apoptosis. Reactive Oxygen Species, particularly H2O2 has been shown to be a key player for this TRAIL sensitization by Hydroxychavicol. We found that ROS decreased XIAP, FLIP in imatinib sensitive K562(S) and imatinib resistant K562(R) both. These XIAP and cFLIP downregulation abrogated their inhibitory effect on Caspase activation and removed its break from extrinsic apoptotic pathway activation by TRAIL and this leads to apoptosis of Imatinib-resistant K562 cells and imatinib sensitive K562 cells. In Imatinibresistant K562 cells, FLIP and XIAP were differentially regulated by JNK and ERK respectively. Akt phosphorylation was decreased by ROS-activated ERK. Dephosphorylation of Akt inhibited its binding to XIAP and that lead to the destabilization of XIAP. On the other hand, ROS-activated JNK increased the expression of an ubiquitin ligase ITCH which degraded FLIP by binding to it and ubiquitination. However, interestingly, when we checked these finding on K562(S) cells, some of the findings were different. In K562(S) cells, ROS degrades XIAP, FLIP by lysosomal degradation pathway. Moreover, JNK alone instead of JNK and ERK played important role in this XIAP and FLIP downregulation. Thus, our findings suggest anti-apoptotic proteins XIAP and FLIP as a viable therapeutic target for Imatinib-resistant CML. We have also identified a novel ROS mediated regulatory pathway of these two proteins which may be further explored for therapeutic targets.
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    Assessment of fluoride induced male reproductive disorders in adult Wistar rats and its amelioration by supplementation of vitamin C and E
    Mukhopadhyay, Prabir Kr
    Fluoride is necessary for tooth and bone development, but excessive exposure causes different system disorders including male reprotoxic consequences. The purpose of this study was to investigate the extent of fluoride toxicities in the male reproductive system and its possible management by vitamin C and E. The study was undertaken to find out the optimum dose of fluoride responsible for causing considerable reprotoxic effects in adult male Wistar rats. The rats were divided into four groups; control (group I) rats received vehicle only and treated rats (group II, III, and IV) were administered sodium fluoride (NaF) orally at 10, 15, and 20 mg/kg/day doses, respectively, for 30 consecutive days. Assessments were done on the following parameters: histoarchitecture of testis and epididymis; spermatozoal potential and DNA integrity; testicular oxidative status, activities of functional marker enzymes and DNA integrity. All these parameters were altered in a dose-dependent manner and based on these; 15 mg/kg/day was selected as the minimum dose responsible for considerable alterations. Further experiments were carried out with this dose. The protective role of VC&VE was assessed on different animal models. Rats were divided into four groups. Group I was the control; Group II received NaF at 15 mg/kg/day dose; Group III was provided with VC (200 mg/kg/day) and VE (400 mg/kg/day) along with NaF; Group IV received only VC&VE for 30 consecutive days. The following studies were undertaken: structure-function integrity of testis, epididymis and spermatozoa; oxidative status of testis and epididymis; testicular functional and steroidogenic status; apoptotic pathway of testis and epididymis; testicular inflammatory status along with spermatozoal apoptotic state. All these parameters were altered due to the fluoride threat. Supplementation with VC&VE restored all the anomalies either to normal or near normal levels. The group IV rats showed a similar pattern of the results to the group I rats.
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    Structure function characterisation of few blue light responsive photoreceptors through biochemical and biophysical approaches
    Mitra, Devrani
    Harvesting light as the primary source of energy is one of the major phenomena behind life on earth which is mediated by several photoreceptors. Photoreceptors are critical for several physiological phenomena viz. photo-acclimatisation, phototropism, stomatal opening etc, thus making its characterisation extremely important in order to use it as optogenetic scaffold. I have been specifically interested in blue light responsive photoreceptors, found exclusively in photosynthetic stramenopile. My work primarily focuses on molecular understanding of aureochromes from two species (Vaucheria frigida and Thalassiosira oceanica) through biochemical and biophysical assays to understand its contribution towards natural phenomena or even using it to intervene in biological pathways. Further I have also explored the principles of protein design and engineering to develop light responsive synthetic transcription factor, suitable for application in optogenetics.
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    Sustainable Water Resource Management of Agriculture in India
    Pramanick, Kousik
    Agriculture (with industry and household sector) is one of three major sectors of human consumption in this Anthropocene era. For assessment of sustainability of agricultural water resource consumption, various methods have been used to get insight into this dimension from multiple perspectives, such as - triple bottom line approach, planetary boundaries framework, doughnut economy etc. At the end, agricultural indicators have been corroborated in accordance with UN SDGs (2030). To exert priority on India (i.e. operational boundary), every analysis has been done in the level of national - scale. The first part was to assess overall sustainability scenario analysis of India using safe and just operating space framework. The second part was to assess the sustainability scenario for water and sanitation sector in India through preparation of a new national water barometer. The third part was to assess the safe and just operating space of agriculture in India along with the contribution of this sector in overall sustainability dimensions. The fourth part was to assess the past and probable future trends of food consumption, water and land requirement for past and future food consumption of almost all of the major agricultural products in India. For all of these works, past trends have been analysed, interactions between biophysical (i.e. ecological) and socioeconomic dimensions have been analysed, probable future projection have been done based on UN and SSP scenarios, and lastly feasible mitigation ways for various challenges have been suggested based on the results of these works. This work would be helpful to understand the Indian context, especially concerning water and agriculture sectors, regarding the sustainable development goals, advocated by UN towards policy formulations in national context.
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    Functional role of Interleukin-6 and Interleukin-10 in the reproductive processes of a teleost fish, Anabas testudineus
    Pramanick, Kousik
    In mammals, interleukin-6 (IL-6) and interleukin-10 (IL-10) has an important function during the reproductive processes, however, the functions of IL-6 and IL-10 in fish have not been elucidated. In the present study, there was quantification of de novo synthesis of ovarian IL-6, IL-10 and tumor necrosis factor-alpha (TNFα) in control and hCG treated fish and results were compared with those from an in vitro study where there was evaluation of the regulatory functions of gonadotropins and TNFα of IL-6 and Il-10 secretions. Relatively greater concentrations of ovarian IL-6 at the post-GVBD (post-germinal vesicle breakdown) stage and higher concentration of ovarian IL-10 in post vitellogenic (PV) and post-GVBD stages indicates IL-6 and IL-10 can modulates reproductive processes. The hCG-induced increase in relative abundance of IL-6 and IL-10 (in vitro) mRNA transcript and secretion from the ovary were attenuated when there was administration of the inhibitor of TNF-α secreting enzyme, TAPI-I, which indicates TNF-α modulates IL-6 secretion and facilitate the production of IL-10. Treatments with IL-6 induced a marked increase in ovulation rate but there was no direct involvement of IL-10 during the time of maturation and ovulation. In vitro established that Il-6 induced ovulation by activating matrix metalloproteinase (MMP). Furthermore, treatment with IL-6 resulted in production of prostaglandin as indicated by the IL-6 induced increase in the abundance of ptgs2 mRNA transcript in the ovary of Anabas testudineus. IL-10 during this process mostly play the regulatory role of the cytokine environment in the oocyte the inhibition of IL-6 when treated with IL-10 in PV follicle establish the fact. Furthermore, results indicate the source of IL-6 and IL-10 in the ovary, is the granulosa cells for IL-6 and both theca and granulosa cells for IL-10 with secretion of IL-6 and IL-10 being induced by the additions of hCG and TNFα in the medium. There was also an IL-6-induced increase in abundance of receptors (IL-6 Rα and gp130) to which it binds indicating IL-6 autoregulates this population of receptors. There was also marked increase in IL-10 receptor IL-10R1 and IL-10R2 suggesting their involvement during the reproductive processes. Stat-3 activation ensured the involvement of IL-6 during the time of ovulation. Results from this study, for the first time, elucidate the reproductive functions of IL-6 in a teleost fish.
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    Investigation of stress induced Tbx20 function in autophagy in heart with comparative analyses of extracellular matrix remodeling with multiple stress inductions in cultured cardiac cell line
    Chakraborty, Santanu
    Tbx20, a T-box transcription factor, is known to be crucial for cardio genesis and murine models with Tbx20 knockout fail to survive beyond E10.5. Tbx20 mutations correspond with severe congenital heart defects including valvulogenesis and septal defects. 1–3 All T-box proteins have a DNA binding domain. The T-box domain of Tbx20 consists of 180 amino acid residues and Tbx20 has a binding affinity to T/2 site [(5’-…AGGTGTGA…-3’ over the consensus T-site 5’-…TCACACCT…-3’. 25 Tbx20 promotes cardiomyocyte proliferation via the Bmp2/pSmad1/5/8 and PI3K/AKT/GSK3β/β-catenin signaling pathways.4 Tbx20 has also been found to act as a cardio-protectant against oxidative stress and downregulation of Tbx20 has been linked to increased apoptosis in cultured rat cardiomyocytes.5 Further, the cardio-protective role of Tbx20 under ROS and hypoxic conditions in the H9c2 cell line was reported. 6 Tbx20 is known to interact with and induce other transcription factors like Nkx2.5 and Gata4 7,8 which are also important for cardiogenesis, maintaining cardiac homeostasis and promoting the expression of Troponin-I and myosin heavy chain protein. Autophagy is an evolutionarily conserved catabolic phenomenon that recycles cellular components to provide for bioenergetics and fuel for cellular survival under stress conditions. At the basal level, the goal of the autophagic machinery is to maintain cellular and organ homeostasis. This is achieved by providing catabolites like fatty acids and amino acids which in turn serve as substrates for many metabolic processes. The cargo (can be organelles, protein aggregates, lipids, cellular proteins) to be degraded is sent to lysosomes via autophagosomes whereby fusion of lysosomes with the latter forms autolysosomes and the cargo is thereafter degraded by lysosomal hydrolases. Autophagy can also be activated under stress conditions like nutrient scarcity/ caloric restriction, ROS (Reactive Oxygen Species) accumulation, ER (Endoplasmic Reticulum) stress, and mitochondrial damage where autophagy serves as a substrate recycling machinery remove protein aggregates and provides much-needed ATP for the survival of cells. 9–11Autophagy has been known to be a critical factor in the survival of neonates postpartum wherein it was found that Atg5 knockout mice models failed to survive after birth. Furthermore, in mice that survived the brief period of nutrient deprivation postpartum (which is the usual scenario), massive upregulation of cardiac autophagy was observed giving away the importance of autophagy in pro-survival while also bringing cardiac autophagy to the centre.12 Impaired and altered autophagy has been an underlying cause of cardiac diseases like AMI (acute myocardial infarction), Ischemic heart disease (IHD) and cardiomyopathy. A similar role of autophagy has been found in acute myocardial infarction wherein inhibition of autophagy enlarges the infarct zone and decreases the ATP content of cardiomyocytes and there have been theories that augmenting autophagy would be a therapeutic approach in restoring the cellular integrity and cardiac functioning in these case13–17 Aging is perhaps one of the greatest risk factors responsible for failing hearts. In fact, aged individuals with no underlying cardiac condition show poor cardiac functionality, diastolic function and left ventricular dilatation. 18–20Accumulation of protein aggregates, misfolded proteins, a poor balance between ROS and anti-oxidants, mitochondrial derangements, attenuated expression of Sirtuins (a class of NAD+ dependent deacetylating enzymes) especially Sirtuin 1, 3 (Sirt 1,3), GSk-3 contribute to cardiac aging.21–23 As such, impaired and poor levels of autophagy are prevalent in aging hearts while apoptotic levels are on a surge. Augmenting autophagy by either calorific restriction or Rapamycin (Rap) administration has shown improvement in cardiac functioning and improved life longevity.24–26 Here in this study for the first time, we demonstrate the role of Tbx20 as a potential candidate to induce anti-senescence-like characteristics in the aging mice population. Autophagy induced expression of Tbx20 activates GSK-3 and transcription factors Nkx2.5, Gata4 and Sirt1 after subjection to starvation (Strv) and rapamycin (Rap) treatment in both in-vivo (BALB/c mice) and in-vitro (H9c2 cell line) model systems. The upregulation of Nkx2.5 and Gata4 following autophagy induction is indicative of progression towards progenitor like cardiomyocyte characteristics, while activation of Sirt1 and GSK3 suggests an anti-aging/ senescence since Sirtuin1 is closely linked with aging, is known to be a mediator of caloric restriction and Sirt1 transgenic mice prevent early mortality. With pre-existing knowledge of the expression of Sirt1 and GSK-3 under autophagy conditions along with the cardioprotective roles they play, these two were chosen as possible candidates that could interact with Tbx20. Further, Tbx20 loss of function (LOF) assay in the H9c2 cell line validated Tbx20-dependent expression of Sirt1, GSK-3, Nkx2.5 and Gata4. On the other hand, ECM remodeling in heart or cardiac remodeling remains an important factor in the pathophysiology of cardiovascular diseases.27,28 Collagen-I forms the major component of the matrix interstitium of the myocardium in addition to Collagen-III, fibronectin, proteoglycans, tissue inhibitors of matrix metalloproteinases (TIMPs) and matrix metalloproteinases (MMPs). The three stages of cardiac remodeling following cardiac injury are inflammatory, proliferative and maturation phases leading to a mature scar formation.29 The preliminary stages of ECM remodeling are necessary as it prevents rupture of the ventricular wall, however, exacerbated ECM remodeling leads to progressive fibrosis in the heart and cardiac malfunctioning.30,31 The MMPs (zinc-dependent proteases) are involved in the turnover of matrix proteins like Collagen.32 Adamts4, a member of Adamts family is an important MMP. Adamts4, also is a disintegrin with thrombospondin like motifs.33,34 The mode of action of Adamts4 is by binding to ECM proteins and thereafter cleaving ECM proteoglycans like aagrecan, versican, brevican in addition to regulating Collagen turnover.35,36 Adamts4 modulates the pathophysiology of osteoarthritis through degradation of matrix proteoglycans and eventually lead to cartilage degradation which manifests as degenerative osteoarthritis.37,38 Besides osteoarthritis, Adamts4, has also been linked with cancer and angiogenesis where its role remains controversial. Some studies report it to be an indicator of early-stage cancer like in cases of colorectal cancer, others findings suggest that its mutated and truncated fragments may suppress tumour growth through inhibition of angiogenesis. 39,40 However, the involvement of Adamts4 in cardiac remodeling is relatively less known. Only a few studies have shown the involvement of Adamts4 in atherosclerotic plaque development.41 and recent studies have shown elevated expression of both Adamts4 and Adamts1 in patients with acute aortic dissection and coronary artery disease.42,43 To decipher the molecular cascade of Adamts4 induction and associated signaling pathway, cultured H9c2 cells were used for in vitro experiments. Adamts4 expression was induced in H9c2 cells following hypoxia (Hyp) and ROS and Hyperglycaemic stress inductions. Additionally, Adamts4 expression was manipulated by siRNA-mediated loss of function and TGF- inhibitor studies with SB431542/ALKI treatment in-vitro to evaluate the hierarchy and dependency on TGF- signaling. TGF- is a known marker for inflammatory and fibrotic responses following pathological stress like Myocardial Infarction, ischemia and reperfusion (I/R) injury.44–48 Ultimately, ADAMTS4 expression was also assessed in patients with cardiac diseases namely Dilated Cardiomyopathy (DCM) and MI. Overall, this study focusses on the role of Tbx20 under stress conditions and ECM remodeling.
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    Studies on the conformational dynamics of HIV-1 accessory proteins to guide new therapeutic development
    Giri, Kalyan
    The HIV-1 accessory proteins (Vpr, Vif, Vpu, and Nef) are multifunctional proteins that play a critical role in the virus progression and contributing to AIDS pathogenesis. These proteins engage with numerous host cellular proteins to execute various functions, promoting viral replication. These proteins show remarkable conformational plasticity i.e. they frequently undergo substantial structural changes upon binding to their targets. In this research, conformational dynamics of these proteins are thoroughly investigated thorough integrated computational modelling and molecular dynamics (MD) simulation techniques in order to explain functional mechanisms and most importantly to explore druggability against these proteins. Conformational analysis revealed novel insights into Vpr's conformational space, particularly the stable embedding of the Vpr C-terminal helix (residues 54-77) within lipid bilayers, marking its likely role as the transmembrane core of the ion channel structure. Full length Vpr undergoes large structural deviations inside lipid bilayer resulting in novel conformations of Vpr. The proposed multimeric Vpr ion channel models in this research offered the first rational attempt for structural understanding of this oligomeric complex which could enhance the therapeutic options. On the other hand, Viprinin and its two potent derivatives emerged as effective inhibitors for Vpr. These findings provide pivotal insights into structure-based drug discovery efforts against HIV-1 accessory proteins. The proposed ion channel models and inhibitor compounds establish a computational framework for future investigations into HIV-1 Vpr structural biology and drug development. Additionally, the analysis of Nef's conformational space identified a conserved druggable pocket implicated in homodimerization, presenting a potential therapeutic target. Utilizing fragment-based approaches, novel lead compounds against Nef were generated and further optimized through advanced MD simulations. These compounds could serve as the starting point for initial stage clinical trials for the discovery of new antiretroviral compounds targeting Nef. This research will lead to development of novel therapeutic options to combat HIV-1 infection in forseeable future in turn leading to significant decrease in loss of lives due to AIDS.
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    Exploring the possibilities of enhancing enzymatic activities of phytopathogenic fungi for their utility in biological control of waterhyacinth
    Ray, Puja
    Global infestation of invasive hydrophyte waterhyacinth [Eichhornia crassipes (Mart.) Solms-Laub. (Pontederiaceae)], has led to an intensive investigation of several methods for its control. Among the most eco-friendly methods implemented, several phytopathogenic fungi are often found to cause damage to their host-plants tissue, through production of phytotoxic metabolites that induce disease symptoms (such as chlorosis, necrosis, etc.), eventually leading to the death of the plants and in the case of weeds, their control. Newline During this study many fungal cultures were isolated from waterhyacinth. 152 fungal isolates, belonging to more than 25 genera were identified by morphological studies. Several potential isolates were subjected to molecular characterization by Sanger sequencing using 18S rDNA. They were evaluated for their biocontrol potential and host-range studies. Among the potential fungal pathogens of waterhyacinth, few have shown to produce an array of lytic, cell-wall-degrading enzymes (CWDEs) that can degrade the polysaccharides of plant cell walls and break the structural moiety of the plants. On the basis of the damage intensity incurred by the primary metabolites on the host weed, the present study highlights on one of the first reports, where xylanases (in its optimised condition), with a molecular weight of 24 kDa, produced by Fusarium oxysporum sp. lycopersici 4287, have shown potency against its targeted host, waterhyacinth (a noxious aquatic weed) by aiming the xylans, which are a major hemicellulosic component of the cell walls. Evolutionary diversion of the responsible enzyme-producing genes (XYL2, XYL3, XYL5) among related species of the selected fungi, also gives an idea of perception of the involvement of these genes in cell-wall degradation. The knowledge of the mode of action with their evolutionary significance eventually helps to predict the breaking of the structural rigidity and moiety of the plant and leading to control its invasiveness, via close relatedness.
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    In vitro propagation and phytochemical screening of three important ethno-medico-botanicals used by the ethnic communities of Purulia district, West Bengal, India
    Giri, Kalyan
    Background: In order to explore the traditional medicine practised by the ethnic communities residing in the Purulia district of West Bengal, India, a quantitative ethnobiological approach was adopted. Three medicinal plants viz. Bacopa monnieri, Aristolochia indica and Rauvolfia serpentina were selected, micropropagted, assessed for clonal fidelity and phytochemical markers. Materials and methods: Ethnobiological surveys were conducted by interviewing a number of informants or traditional healers with the help of a semi-structured questionnaire. The survey included questions on botanical ingredients and additives, vernacular names of the plants and animals, methods of preparation and administration and restrictions during medications. Additional quantitative indices such as use value, informant’s consensus factor and fidelity level were used for data analysis. On the basis of use value three plants viz. B. monnieri, A. indica and R. sepentina were selected and micropropagted in presence of various plant growth regulators (PGRs) and/or polyamines (PAs). Clonal fidelity of the three micropropagated plants were assessed by RAPD and ISSR based markers. Further, the plants were analyzed by validated HPTLC methods for the presence of marker compounds such as bacoside A, aristolochic acid I, reserpine, ajmalicine and stigmasterol. Results: A number of folkloric use of botanicals were reported by the traditional healers. High frequency in-vitro multiplication and regeneration in the three selected plants were achieved via use of PGRs and/or PAs. Clonal fidelity assessment of micropropagated plants using two markers (RAPD and ISSR) systems revealed high genetic homogeneity and low level of polymorphism. Comparative HPTLC analysis of bacoside A, aristolochic acid I and reserpine, ajmalicine and stigmasterol content in natural and in-vitro grown B. monnieri, A. indica and R. serpentina respectively indicated higher concentrations of bioactive phytochemicals in tissue-culture raised plants. Conclusion: Possible synergistic interactions among phytochemicals and additives were indicated to explain enhanced therapeutic efficacy of mixed herbal formulations. Moreover, in-vitro high frequency multiplication and regeneration from various explants may serve as exciting culture material for propagation and conservation of this valuable medicinal plant. HPTLC studies clearly indicated that in-vitro raised plant samples can be used as excellent resource for qualitative and quantitative estimation of high value pharmaceuticals.
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    Understanding the Regulation of Mitochondrial Homeostasis by SARMI and its role in Neurodegeneration
    Mukherjee, Piyali
    With the increase in life expectancy neurodegenerative diseases like Alzheimer s disease (AD) and Parkinson s disease (PD) are on the rise. While neurodegeneration has been studied in the context of various pathological conditions, not much is known on the molecular mechanisms that cause/regulate axonal retraction during aging. Identification of key targets that delay the process of neuronal death before they reach the point of no return may enhance their longevity and prevent subsequent disease pathology. SARM1 (Sterile alpha and TIR motif-containing 1 protein) is a key molecule that plays a pivotal role in axonal death. To study the role of endogenous SARM 1 we established a cellular model of neurodegeneration in SH-SY5Y cells by treatment with the mitochondrial complex I inhibitor rotenone. We showed that rotenone induced neuronal death through SARM1 activation that was accompanied by increased inflammation, deregulation of electron transport chain (ETC) complex genes and defective autophagy. To study age-associated neurodegeneration, we established a drosophila model of aging for the study of age-dependent vulnerability to rotenone, a pesticide that has been implicated in sporadic cases of PD. Our results showed that age plays a major role in the increased susceptibility to rotenone that is accompanied by decreased lifespan, severe locomotor deficits, and loss of dopaminergic neurons. Rotenone exposure results in the SARM1 induction that is accompanied by an increased inflammatory response and independent of ROS generation. Thus, this study aims to provide a detailed mechanistic insight into the regulation of neuronal homeostasis by SARM1 and its implication in age-associated neurodegeneration.
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    Characterization of the Bambusa tulda Roxb inflorescences and flowers at the morphological anatomical and genetic levels to understand floral organ developments and differentiation in bamboo
    Das, Malay
    Bamboos belong to the monocotyledonous plant family Poaceae and subfamily Bambusoideae. Bamboos represent an extreme example of perennialism, where the reproductive phase begins after completion of an extended vegetative phase, which may vary across species. Other than delayed flowering time, existence of two different types of inflorescences, genetics of floral development and nature of pollen compatibility make bamboo unique in comparison to other grasses. The main aim of this study was to understand the floral organ development and pollination mechanism in Bambusa tulda. In this study, the relative abundance of two different types of inflorescence in an entire flowering cycle were analysed and rate of seed setting was compared. One potential limitation to perform gene expression analyses on Bambusa members was the absence of suitable reference genes to normalize expression data. In this study, reference genes were identified, which were stable across species, organs and developmental stages. In order to understand the molecular mechanism that regulates flower development, the floral meristem identity genes MADS14, MADS15 and MADS18 were sequenced from B. tulda and their expression pattern was analyzed across different vegetative and reproductive tissues. In order to understand the genetics of pollen compatibility in bamboo, in vivo pollination experiments were performed. The finding indicated that B. tulda is primarily a cross pollinated species. In order to further understand the molecular mechanism regulating genetic compatibility in bamboo, selected members of RNase T2 and Fbox gene families were studied. Overall, the findings of this study will be useful to understand the morphological, ecological and molecular basis of flower development and genetic compatibility in bamboos.
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    Studies on the diversity and ecology of zooplankton population in Sundarban Estuarine System (SES), West Bengal, India
    Mandal, Sumit
    Zooplankton play pivotal role in estuarine ecosystem. The relative importance of different environmental parameters in determining the diversity and ecology of zooplankton have been investigated from Sundarban Estuarine System (SES), India. The initial observation was designed to decipher the effect of monsoon on zooplankton species diversity, abundance along with physiochemical factors at river Saptamukhi of SES. Significant intra-monsoonal changes of zooplankton population correlated with several environmental parameters were documented. Additionally, the spatial-temporal distribution of zooplankton were recorded based on different multivariate statistics and indicator value (IndVal) analysis from the river Matla in the eastern part of SES. Seasonal occurrence of dominant taxa with high IndVal index was noticeably observed and it can be used as potential bioindicator for particular season and environmental condition in this estuarine system. Exclusive occurrence of warm water species indicated that the area is under threat of climate change mediated temperature rise. Altogether, 56 zooplankton taxa were identified with copepods forming the predominant population. The zooplankton density was highest in winter, followed by monsoon, summer and spring. Different time series observations were also carried out to unravel the specific diel and tidal variations of economically important shellfish larvae. It has been established that, their early developmental stages utilize the tidal currents for ingress and egress mechanisms in order to migrate horizontal distances and/or remain in their preferred habitats. Moreover, Metapenaeus dobsoni was also selected as a proxy to understand the diel, tidal and ontogenetic changes in their abundance within SES during two different tidal phases. Finally, the impact of climate change mediated elevated temperature on the physiology of a meroplankton species has been assessed through mesocosm experiment by using Penaeus monodon post larvae as a model organism. The growth, survival percentages, ingestion and absorption rate were decreased; howbeit respiration and ammonia excretion rate had been increased in elevated temperature resulted a negative Scope for Growth in stressful environment. The present work provides a benchmark for Sundarban zooplankton species diversity and distribution as well as their diel and tidal variations with respect to different environmental parameters for planning suitable conservation strategies and sustainable development in future.
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    Identification of candidate tumor suppressor genes’ loci on chromosome 9 associated with the development of arsenic induced urinary bladder cancer in West Bengal, India
    Ghosh, Amlan
    The etiological link of arsenic with bladder cancer (BC) is well established across the globe. The molecular pathogenesis of arsenic induced BC should be explored to identify potential markers of clinical importance for better disease management. Arsenic toxicity is a burning health issue along Gangetic belt of West Bengal and higher BC incidence was recorded in affected areas of the state than safe areas. On this background, present hospital-based study aimed to analyse the association of arsenic with development/progression/prognosis of BC in West Bengal and, explore molecular pathogenesis of arsenic-induced BC targeting candidate tumor suppressor genes (TSGs) of chromosome-9 due to previous reports of alteration of the chromosome in BC. In this hospital-based study, majority of BC patients were documented from arsenic affected areas of the state and in these patients, concordantly high tumor arsenic level (AsH, >100 ppb) was detected. High tumor arsenic level was found to be associated with higher proliferation potential (assessed by immunohistochemical analysis of ki67) and pathological stages of tumor and poor patient survival. Thus, in exposed individuals, arsenic accumulates in bladder tissue to influence tumorigenesis and favour acquisition of aggressive tumor phenotypes that affect disease outcome. To explore molecular pathogenesis, 9p22-21 and 9q22.3 were selected based on previous report and candidate TSGs deleted in these regions in AsH tumors were detected by analysing whole genome CGH+SNP array data of our previous study. In 9p22 region, SH3GL2 (SH3 domain containing GRB2 like 2) showed molecular alteration (deletion & promoter methylation) preferably in AsH tumors similar to array based data and, concordant reduced expression. SH3GL2 inactivation seemed to affect receptor mediated endocytosis of active EGFR as evident from overexpression of the later without any amplification of gene in same sample set. SH3GL2 inactivation and associated dysregulation in “negative regulation of ERBB signalling pathway” was seen to have prognostic significance. In 9q22.3 region, deletion, promoter methylation, and concordant reduced expression of PHF2 was seen preferentially in AsH tumors. PHF2 (PHD finger protein 2) involves in “histone lysine (H3K9me2) demethylation pathway” essential for p53 functioning. In present study, PHF2 inactivation might affect p53 mediated transcription as evident from reduced p21 expression in same set of tumors over- expressing p53 protein. CDKN2A and CDKN2B loci from 9p21 region, FANCC and PTCH1 loci from 9q22.3 region were also analysed in this study. As evident from comparable and high frequency of molecular alteration in AsH and AsL (arsenic low; ≤100 ppb) tumors, the gene loci did not seem to have important contribution in pathogenesis of arsenic induced BC. The information on association of arsenic with disease progression, prognosis and related molecular pathogenesis will have implementation in designing preventive and management strategies for arsenic induced bladder cancer in future.