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PublicationArticle Testicular changes in rat exposed to Trichloroacetic acid (TCA) during organogenesis(2005) Royana SinghHalogenated hydrocarbons such as Trichloroacetic acid (TCA) are among the most common water supply contaminants in the world. The study was, therefore undertaken to examine the effect of Trichloroacetic acid on the developing testis of Charles foster rat. The rats were randomly placed in the test groups and exposed to various concentrations of TCA i.e. 1000, 1200, 1400, 1600 and 1800 mg/Kg body weight by oral gavage throughout the period of organogenesis, from day 6 to 15 of gestation. TCA was administered in the form of sodium trichloroacetate, which in the body is reduced to trichloroacetic acid by P450 enzyme in the liver. TCA administration led to dose related reduction in the fetal weight and the testicular weight, when they were collected on day 19 of gestation. Control mothers were administered equal volume of distilled water. Histological studies of the testis when compared to the controls revealed decrease in the length and diameter, of the seminiferous tubules with 1400 mg/kg and higher doses. The rapid assault on the cellular components with the increase in the TCA concentration causing enhanced apoptosis of the gonocytes were well evident, with the sub-sequel lying in the total reduction in the testicular size.PublicationArticle Gender-specific antitumor action of aspirin in a murine model of a T-cell lymphoma bearing host(2012) Anjani Kumar; Naveen Kumar Vishvakarma; Alok Chandra Bharti; Sukh Mahendra SinghAspirin is an anti-inflammatory drug demonstrated to possess a tremendous anticancer potential. As progression of some tumors is influenced by sex hormones, we investigated if the antineoplastic action of aspirin shows gender dependence. Using a murine model of T-cell lymphoma, the present investigation was undertaken to study if the antitumor actions of aspirin against lymphoma cells display gender dimorphism. The findings of the present investigation indicate that aspirin administration to male and female tumor-bearing hosts resulted in gender dependent differential tumor growth retardation. Such gender dichotomy of aspirin's antitumor action was associated with a differential impact on cell cycle progression and expression of cell survival regulatory molecules. Aspirin administration was also found to modulate crucial parameters of tumor microenvironment, including contents of glucose, lactate and cell growth regulatory cytokines, in a gender specific manner. Aspirin was found to reverse estrogen-dependent augmentation of tumor cell survival in vitro. Taken together the results of the present study suggest that the antineoplastic action of aspirin is gender-dependent and should be considered in designing of gender-specific therapeutic applications of aspirin. © 2011 Elsevier Inc..PublicationArticle “Sustainable synthesis of Camellia sinensis-mediated silver nanoparticles (CsAgNP) and their anticancer mechanisms in breast cancer cells”(Elsevier Ltd, 2025) Rupen Tamang; Abhishesh Kumar Mehata; Virendra Pratap Singh; Madaswamy Sona S Muthu; Biplob KochThe present investigation focuses on synthesizing eco-friendly and cost-effective silver nanoparticles (CsAgNP) utilizing Camellia sinensis ethanolic extract (CsE) as a reducing agent and investigating the potential enhancement in its anticancer efficacy as compared to CsE. The CsAgNP formation was confirmed through the color change from pale green to dark brown and further validated using UV–visible spectroscopy in the 400-450 nm range. The optimal CsAgNP synthesis parameters include 1:4 ratio of CsE: 1 mM AgNO3, 60 min of duration and 50 °C reaction temperature. The morphology and the size of nanoparticles were estimated using AFM, SEM and TEM where the results showed a smooth topography with a size <100 nm. The CsAgNP crystalline form was confirmed through SAED pictures and silver's presence confirmed through EDX analysis. FTIR study ascertained the capping agents and distortion in functional groups compared to CsE. The anticancer potency of CsAgNP and crude extract (CsE) was assessed against the T-47D breast cancer cells by MTT assay. CsAgNP displayed strong activity towards T-47D cells (IC50 8 μg/ml) compared to CsE and relatively low activity towards the normal HEK-293 cells. Further, fluorescence microscopy and flow cytometry data revealed that the CsAgNP promotes apoptosis and also induces G2-M phase cell cycle arrest. Furthermore, CsAgNP treatment decreases p53 and Bcl-2 protein expression, while increasing Bax, Cytochrome c and Caspase-3 levels, indicating mitochondrial-mediated apoptotic pathway activation. Thus, our research aims to investigate the potential of using Camellia sinensis to synthesize CsAgNP, a potent drug delivery system, to enhance anticancer effectiveness and advance cancer therapy in the future. © 2024 Elsevier B.V.PublicationArticle The hypothalamic neuropeptide orexin A– a possible regulator in glucose homeostasis and germ cell kinetics in adult mice testes(Elsevier B.V., 2018) Deepanshu Joshi; Debarshi Sarkar; Shio Kumar SinghOrexin A (OXA), a hypothalamic neuropeptide, regulates food intake, sleep-wake cycle and energy balance by binding to its receptor (OX1R). Apart from brain, OXA and OX1R are also present in peripheral organs including reproductive tissues. Mammalian reproduction depends on uptake and proper utilization of glucose in the testes. This study, therefore, examined role of OXA/OX1R system in regulation of glucose homeostasis in adult mouse testis under in vivo and ex vivo conditions. Binding of OXA to OX1R was blocked using an OX1R antagonist, SB-334867. Mice were given a single bilateral intratesticular injection of the antagonist at doses of 4 and 12μg/mouse and sacrificed 24 h post-injection. In order to understand the direct role of OXA in testes of adult mice, an ex vivo experiment was performed where binding of OXA to OX1R in the testis was blocked by using the same OX1R antagonist. The antagonist treatment affected testicular glucose and lactate concentration with concomitant down-regulation in the expression of glucose transporters 3 and 8. A decreased activity in lactate dehydrogenase enzyme and imbalance between germ cell survival and proliferation were also noted in testes in treated mice. The results of ex vivo study supported the results obtained from in vivo study. The findings thus suggest involvement of OXA/OX1R system in regulation of testicular glucose homeostasis and germ cell kinetics in adult mice. © 2018 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM)PublicationArticle DLin52 is crucial for dE2F and dRBF mediated transcriptional regulation of pro-apoptotic gene hid(Elsevier, 2014) Pradeep Kumar Bhaskar; Satya Surabhi; Bipin Kumar Tripathi; Ashim Mukherjee; Mousumi MutsuddiDrosophila lin52 (dlin52) is a member of Myb transcription regulator complex and it shows a dynamic pattern of expression in all Drosophila tissues. Myb complex functions to activate or repress transcription in a site-specific manner; however, the detailed mechanism is yet to be clearly understood. Members of the Drosophila melanogaster Myb-MuvB/dREAM complex have been known to regulate expression of a wide range of genes including those involved in regulating apoptosis. E2F and its corepressor RBF also belong to this complex and together they regulate expression of genes involved in cell cycle progression, apoptosis, differentiation, and development. In the present study, we examined whether the depletion of dlin52 in developing photoreceptor neurons results in enhanced apoptosis and disorganisation of the ommatidia. Strikingly, we found that dLin52 is essential for transcriptional repression of the pro-apoptotic gene, hid; decrease in dlin52 levels led to dramatic induction of hid and apoptosis in eye-antennal discs. Reduction of Rpd3 (HDAC1), another member of the dREAM complex, also led to marginal upregulation of Hid. In addition, we also demonstrated that an optimum level of dLin52 is needed for dE2F1/2 activity on the hid promoter. dlin52 cooperates with dRBF and dE2F1/2 for recruitment of repressor complex on the hid promoter. Preliminary data indicate that Rpd3/HDAC1 also contributes to hid repression. Based on the findings, we conclude that dLin52 functions as a co-factor and modulates activity of members of dMyb/dREAM complex at hid promoter, thus regulating apoptosis by repressing this pro-apoptotic gene in the developing Drosophila eye. © 2014 Elsevier B.V.PublicationArticle Lysophosphatidic acid promotes survival of T lymphoma cells by altering apoptosis and glucose metabolism(Springer, 2020) Vishal Kumar Gupta; Pradip Kumar Jaiswara; Pratishtha Sonker; Shiv Govind Rawat; Rajan Kumar Tiwari; Ajay KumarLysophosphatidic acid (LPA) is a bioactive lipid, which plays an indispensable role in various physiological and pathological processes. Moreover, an elevated level of LPA has been observed in malignancies of different origins and implicated in their progression via modulation of proliferation, apoptosis, invasion and metastasis. Interestingly, few recent reports suggest a pivotal role of LPA-modulated metabolism in oncogenesis of ovarian cancer. However, little is understood regarding the role of LPA in the development and progression of T cell malignancies, which are considered as one of the most challenging neoplasms for clinical management. Additionally, mechanisms underlying the LPA-dependent modulation of glucose metabolism in T cell lymphoma are also not known. Therefore, the present study was undertaken to explore the role of LPA-altered apoptosis and glucose metabolism on the survival of T lymphoma cells. Observations of this investigation suggest that LPA supports survival of T lymphoma cells via altering apoptosis and glucose metabolism through changing the level of reactive species, namely nitric oxide and reactive oxygen species along with expression of various survival and glucose metabolism regulatory molecules, including hypoxia-inducible factor 1-alpha, p53, Bcl2, and glucose transporter 3, hexokinase II, pyruvate kinase muscle isozyme 2, monocarboxylate transporter 1, pyruvate dehydrogenase kinase 1. Taken together‚ the results of the present investigation decipher the novel mechanisms of LPA-mediated survival of T lymphoma cells via modulation of apoptosis and glucose metabolism. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.PublicationArticle Characterisation of cholinesterases in mucous secretions and their localisation in epidermis of Labeo rohita and Cirrhinus mrigala(Springer Netherlands, 2019) Ashwini Kumar Nigam; Neeraj Verma; Ayan Srivastava; Usha Kumari; Swati Mittal; Ajay Kumar MittalCholinesterases are multifunctional enzymes and have been associated with diverse physiological functions in addition to their classical role at synapses. In the present study, cholinesterase (ChE) isozymes have been characterised in mucous secretions and their activity has been localised in the epidermis of Labeo rohita and Cirrhinus mrigala. Zymography using specific substrates and inhibitors revealed the presence of two ChE isozymes—ChE-1 and ChE-2. The isozyme ChE-1 was characterised as an atypical butyrylcholinesterase and ChE-2 as a typical acetylcholinesterase in skin mucous secretions of both the fish species. Enzyme histochemical analysis demonstrated the presence of ChE activity in the epidermis of the fish species investigated. In both the fish species, strong ChE activity was observed in the outer-layer epithelial cells, taste buds and neuromasts. The middle and basal layer epithelial cells showed moderate to weak ChE activity. Club cells and mucous goblet cells showed the absence of ChE activity. Characterisation with specific inhibitors indicates that acetylcholinesterase (AChE) was the major cholinesterase type expressed in the epidermis of the two fish species investigated. Immunohistochemical localisation of apoptotic and cell proliferation markers, in addition, revealed high expression of active caspase 3 in the outer-layer epithelial cells, and proliferating cell nuclear antigen (PCNA) in the middle and basal layer epithelial cells. High ChE activity in caspase 3-positive cells in the outer layer of the epidermis and low in PCNA-positive cells in middle and basal layers could point towards the possible involvement of ChEs in cell death and their final extrusion from skin surface. © 2019, Springer Nature B.V.PublicationArticle Expression of procaspase 3 and activated caspase 3 and its relevance in hormone-responsive gallbladder carcinoma chemotherapy(2013) Sanjeev Kumar Maurya; Mallika Tewari; Bechan Sharma; Hari Shanker ShuklaBackground/Aims: The higher incidence of gallbladder cancer (GBC) in females has been accredited to the involvement of hormones. The clinical implications of sex hormone receptors in GBC are well established. Cysteine proteases (such as caspase-3-9, etc.) are known to play a central role in the apoptotic pathway. Of these, the downstream enzyme caspase-3 is often activated in the apoptotic path-way. The aim of this work was to examine the status of apoptosis (which directly correlated with the level of active caspase-3) in hormone-responsive GBC. Methods: We used 10 androgen receptor (AR)-positive, 14 estrogen receptor (ER)-positive, 12 HER/neu-positive, eight triple positive, and 10 triple negative malignant GBC human tissue samples. We isolated the total cellular protein from tumor tissues and carried out Western blotting using antipro-caspase-3 and anti-activated caspase-3 antibodies. Results: ER and HER/neu-positive GBC exhibited high caspase-3 activity and low procaspase-3 activity, whereas AR-positive GBC showed no significant level of apoptosis. We also evaluated the apoptosis status of triple positive GBC and triple negative GBC, and found significant apoptosis in triple positive GBC. Conclusions: The results indicate that ER and HER/neu-positive GBCs had active apoptosis, whereas AR-positive GBC was highly resistant to apoptosis. © 2013 The Korean Association of Internal Medicine.PublicationArticle Tempol (4 hydroxy-tempo) inhibits anoxia-induced progression of mitochondrial dysfunction and associated neurobehavioral impairment in neonatal rats(Elsevier B.V., 2017) Puneet K. Samaiya; Gopeshwar Narayan; Ashok Kumar; Sairam KrishnamurthyBackground Anoxia leads to a robust generation of reactive oxygen species/nitrogen species which can result in mitochondrial dysfunction and associated cell death in the cerebral cortex of neonates. Aim The present study investigated the pharmacological role of tempol in the treatment of rat neonatal cortical mitochondrial dysfunction induced insult progression (day-1 to day-7) and associated neurobehavioral alterations post-anoxia. Methods Rat pups of 30 h age or postnatal day 2 (PND2) were randomly divided into 5 groups (n = 5 per group): (1) Control; (2) Anoxia; (3) Anoxia + Tempol 75 mg/kg; (4) Anoxia + Tempol 150 mg/kg; and (5) Anoxia + Tempol 300 mg/kg, and subjected to two episode of anoxia (10 min each) at 24 h of time interval in an enclosed chamber supplied with 100% N2. Results Tempol significantly decreased nitric oxide ([rad]NO) formation and simultaneously improved superoxide dismutase (SOD) and catalase (CAT) activities. Further, we observed a significantly (P < 0.05) improvement in mitochondrial respiration, complex enzyme activities, mitochondrial membrane potential (MMP) along with attenuation of transition pore opening (MPT) after treatment with tempol. Furthermore, tempol decreased expression of mitochondrial Bax, cytochrome-C, caspase-9 and caspase-3 while the increase in expression of cytoplasmic Bax, mitochondrial Bcl-2 on day-7 in cortical region indicating regulation of intrinsic pathway of apoptosis. Further, it improved anoxia-induced neurobehavioral outcome (hanging and reflex latencies). Conclusion Biochemical, molecular and behavioral studies suggest the role of tempol in preserving mitochondrial function and associated neurobehavioral outcomes after neonatal anoxia. © 2017 Elsevier B.V.PublicationArticle Non-apoptotic function of apoptotic proteins in the development of Malpighian tubules of Drosophila melanogaster(2011) Madhu G Tapadia; Naveen K GautamDrosophila metamorphosis is characterized by the histolysis of larval structures by programmed cell death, which paves the way for the establishment of adult-specific structures under the influence of the steroid hormone ecdysone. Malpighian tubules function as an excretory system and are one of the larval structures that are not destroyed during metamorphosis and are carried over to adulthood. The pupal Malpighian tubules evade destruction in spite of expressing apoptotic proteins, Reaper, Hid, Grim, Dronc and Drice. Here we show that in the Malpighian tubules expression of apoptotic proteins commences right from embryonic development and continues throughout the larval stages. Overexpression of these proteins in the Malpighian tubules causes larval lethality resulting in malformed tubules. The number and regular organization of principal and stellate cells of Malpighian tubules is disturbed, in turn disrupting the physiological functioning of the tubules as well. Strikingly, the localization of β-tubulin, F-actin and Disclarge (Dlg) is also disrupted. These results suggest that the apoptotic proteins could be having non-apoptotic function in the development of Malpighian tubules. © 2011 Indian Academy of Sciences.