HIV1-Nef perturbs the integrity of blood testis barrier in rat model.

The blood-testis barrier is a specialized feature within the mammalian testis, located in close proximity to the basement membrane of seminiferous tubules. This barrier serves to divide the seminiferous epithelium into distinct basal and adluminal (apical) compartments. The selectivity of the BTB to foreign particles makes it a safe haven for the virus, and the high affinity of HIV for testis might lead to the vertical transmission of the virus. In the present study, recombinant HIV1-Nef (rNef) protein was injected intravenously to examine the effect of rNef on BTB. SD male rats received 250 µg and 500 µg of rNef along with 2% Evans blue dye within 1 ml through the tail vein. After 1 hour of perfusion, the animals were sacrificed for analysis. The dye migration assay and ELISA confirmed a significant impairment in the blood-testis barrier (BTB) and the manifestation of rNef in testes tissues, respectively. Moreover, a decline in the expression of tight junction proteins, including ZO1 and Occludin, was observed during rNef-induced BTB disruption. Overall, our findings demonstrated that rNef induces BTB disruption through various signaling events. At the site of ectoplasmic specialization of the seminiferous epithelium, the localization of cadherins was found to be disrupted, making the testis a vulnerable site. In conclusion, rNef perturbs the integrity of the blood-testis barrier in rat models; hence, it can also serve as a suitable model for studying the dynamics of the blood-testis barrier.

Established a rodent model to study the integrity of the blood testis barrier (BTB).Recombinant Nef (rNef) of HIV1 can breach the toughest physiological barrier of BTB.Integrity of BTB gets interrupted by rNef through the 'disengagement' and 'engagement' mechanisms of BTB dynamics.Major constituent proteins of BTB, including Occludin and ZO-1 were found to be highly disrupted by rNef; and seem to be the key aberrant for the compromised BTB.rNef also dislocated the localization of N & E cadherins in the rat testes; which would have affected the cadherin-based epithelial adhesion system of BTB and finally caused the breach.

Genetic and epigenetic alterations in DNA repair genes and treatment outcome of chemoradiotherapy in cervical cancer.

Cervical cancer (CaCx) is the deadliest malignancy among women which is caused by human papillomavirus (HPV) and anthro-demographical/clinicopathological factors. HPV oncoproteins E6 and E7 target p53 and RB (retinoblastoma) protein degradation, Ataxia telangiectasia mutated (ATM), ATM-RAD3-related (ATR) inactivation and subsequent impairment of non-homologous end joining (NHEJ), homologous recombination, and base excision repair pathways. There is also an accumulation of genetic and epigenetic alterations in Tumor Growth Suppressors (TGS), oncogenes, and DNA repair genes leading to increased genome instability and CaCx development. These alterations might be responsible for differential clinical response to Cisplatin-based chemoradiotherapy (CRT) in patients. This review explores HPV-mediated DNA damage as a risk factor in CaCx development, the mechanistic role of genetic and epigenetic alterations in DNA repair genes and their association with CRT and outcome, It also explores new possibilities for the development of genetic and epigenetic-based biomarkers for diagnostic, prognostic, and molecular therapeutic interventions.

Pax6 affects Ras-Raf-ERK1/2 in mouse aging brain.

Pax6, a transcription factor and multifunctional protein, changes during aging. It also interacts with regulator proteins involved in cell metabolism and survival signalling pathways including Ras-GAP. Many forms of Ras, Raf and ERK1/2 are known but information on their region-specific expression patterns are unavailable from brain during aging. Therefore, it has been intended to evaluate expressions of Pax6 and forms of Ras, Raf, ERK1/2 in hippocampus, caudate nucleus, amygdale, cerebral cortex, cerebellum and olfactory lobe. Association of Pax6 with Ras, Raf and ERK1/2 was evaluated in co-culture (PC-12, C6-glia, U-87 MG) of neuroglia cell lines. Impacts of Pax6 were evaluated by siRNA mediated knockdown and expression patterns Ras-Raf-Erk1/2. Analysis of activities of Pax6 and impacts of 5'AMP, wild-type and mutant ERK were done by RT-PCR and luciferase reporter assay. Results indicate age-dependent changes of Pax6, Ras, Raf, ERK1/2 in different regions of brain of young and old mice. Erk1/2 shows synergistic activities to Pax6.

A Study of Arginase Expression in Chronic Non-healing Wounds.

Arginase expression has been recently shown to increase in numerous disease states like neurodegeneration, inflammation, and malignancies. Although it has been found to be functionally important in various disease pathologies, little is known about its role in wound healing. Here, we look at the expression of arginase and its isoforms in chronic non-healing wounds and also study the expression of nitric oxide synthase (NOS) and oxidative stress enzymes in them. Wound tissues and blood samples were collected at the time of index presentation and follow-up from 61 chronic non-healing wound cases. The expression patterns of arginase isoenzymes, NOS, superoxide dismutases (SOD), lactic acid dehydrogenase (LDH), and catalase were examined by using enzyme-linked immunosorbent assay, immunohistochemistry, and western blot analysis at the transcript and protein level. We reported a significant decrease of serum arginase levels in chronic nonhealing wounds in the progress of wound healing. Interestingly, tissue arginase levels were found to be increased with improved wound condition at follow-up. Tissue NOS, LDH, and catalase activity were also found to be increased with the progress of healing, whereas SOD levels were downregulated. Our findings reported increased expression at the transcript level of arginase-I and arginase-II in chronic non-healing wounds for the first time. In conclusion, we observed decreased serum arginase levels in completely healed patients as compared to non-healed cases. Our study findings support the hypothesis that inhibition of the activity of arginase delays wound healing. Arginase and iNOS may also find their place in the future as possible biomarkers for wound healing.

Co-expression and Interaction of Pax6 with Genes and Proteins of Immunological Surveillance in the Brain of Mice.

The Pax6 binds to promoter sequence elements of genes involved in immunological surveillance and interacts with Iba1, p53, Ras-GAP, and Sparc in the brain of mice. The Pax6 also affects the expression pattern of genes involved in neurogenesis and neurodegeneration. However, the expression and association of Pax6 in the brain under immunologically challenged conditions are still elusive. Therefore, it has been intended to analyze the association of Pax6 in the immunity of the brain using the immune-challenged Dalton's lymphoma (DL) mice model. The expressions of Pax6, Iba1, and Tmem119 decreased, but expressions of Ifn-γ, Tnf-α, Bdnf, and Tgf-ß increased in the brain of immune-challenged mice as compared to the control. The level of co-expression of Pax6 decreased in dual positive cells with Iba1, Tmem119, Sparc, p53, Bdnf, and Tgf-ß in the brain of immune-challenged mice. Binding of Pax6 to multiple sites of the promoter sequences of Bdnf and Tgf-ß indicates their Pax6-associated differential expression and association with immune responsive gene. The levels of binding of Pax6 to Tmem119, Iba1, Ifn-γ, and Tnf-α got altered during the immune-challenged state as compared to control. Results provide the first evidence of the association of Pax6 in brain-specific immunity.

Molecular docking studies of natural immunomodulators indicate their interactions with the CD40L of CD40/CD40L pathway and CSF1R kinase domain of microglia.

Natural products have proved beneficial in reducing neuroinflammation in neurological diseases. Their impacts have also been associated with the activities of microglia, responsible for brain-specific immunity. Recent studies have shown the involvement of the number of microglia-specific proteins in the regulation of brain-specific immunity. However, molecular targets of natural products and their mechanism of interaction with microglia-specific proteins are elusive. Since the genetic signature of microglia offers many potential targets for drug discovery, molecular docking followed by molecular dynamics (MD) simulations of cluster of differentiation 40 ligand (CD40L) and colony-stimulating factor 1 receptor (CSF1R) kinase domain protein with some known neuro-immunomodulators (Curcumin, Cannabidiol, Ginsenoside Rg1, Resveratrol, and Sulforaphane) has been evaluated. Curcumin and cannabidiol were observed likely to modulate CD40L and expression of cytokines and entry of inflammatory cells. Resveratrol and cannabidiol may affect the CSF1R kinase domain and activation of microglia. Our finding suggests that curcumin, cannabidiol, and resveratrol may serve specific drug ligands in regulating microglia-mediated brain immunity.

Autoregulation of Pax6 in neuronal cells is mediated by Pax6(5a), Pax6(ΔPD), SPARC, and p53.

BACKGROUND: Pax6, a multifunctional protein and a transcriptional regulator is critical for optimal functioning of neuronal cells. It is known that alternatively spliced Pax6 isoforms and co-expressed interacting proteins mediate cell/tissue specific autoregulation of Pax6, however, underlying mechanism(s) are poorly understood. METHODS AND RESULTS: We used Neuro-2a cells to explore the mechanism of autoregulation of Pax6 in neuronal cells whereas NIH/3T3 cells were used as control. We first studied the transcript expression of the three Pax6 isoforms: Pax6, Pax6(5a), and Pax6(ΔPD); and the two co-expressed Pax6-interacting partners: SPARC and p53 in normal and overexpressed conditions, through the semi-quantitative RT-PCR. Further, we used the luciferase reporter assay to study the binding and transactivation of the three Pax6 isoforms: Pax6, Pax6(5a), and Pax6(ΔPD) to their respective promoters: P0, P1, and Pα; followed by that of the two co-expressed Pax6-interacting partners: SPARC and p53 to the Pax6-P1 promoter. Expression and distribution of Pax6, Pax6(5a) and Pax6(ΔPD), their binding to Pax6-promoters (P0, P1, and Pα) and transactivation were modulated in transfected Neuro-2a cells. CONCLUSION: Our results suggest that autoregulation of Pax6 in neuronal cells is driven by a promoter dependent mechanism which is mediated by spliced variants [Pax6(5a) and Pax6(ΔPD)] and interacting proteins (SPARC and p53) of Pax6.

Insights on Epidemiology, Pathogenesis, Diagnosis and Possible Treatment of COVID-19 Infection.

The sudden outbreak of the novel coronavirus infection (COVID-19, SARS-CoV-2 virus) is posing a significant threat by affecting millions of people across the globe showing mild to severe symptoms of pneumonia and acute respiratory distress. The absence of precise information on primary transmission, diagnosis, prognosis, and therapeutics for patients with COVID-19 makes prevention and control tough. In the current scenario, only supportive treatment is available, which in turn possess a biggest challenge for scientists to develop specific drugs and vaccines for COVID-19. Further, India, with the second largest populated country and fluctuating climatic conditions quarterly, has high vulnerability towards COVID-19 infection. Thus, this highlights the importance of a better understanding of the COVID-19 infection, pathology, diagnosis and its treatment. The present review article has been intended to discuss the COVID-19 biology, mechanism of infection in humans with primary effects on pregnancy, the nervous system, diabetes, and cardiovascular disease. The article will also discuss the drug repurposing strategy as an alternative line of treatment and clinical practices recommended by the World Health Organization and other government agencies and represent the COVID-19 scenario with the Indian context.

Transcriptional and epigenetic regulation of microglia in maintenance of brain homeostasis and neurodegeneration.

The emerging role of microglia in brain homeostasis, neurodegeneration, and neurodevelopmental disorders has attracted considerable interest. In addition, recent developments in microglial functions and associated pathways have shed new light on their fundamental role in the immunological surveillance of the brain. Understanding the interconnections between microglia, neurons, and non-neuronal cells have opened up additional avenues for research in this evolving field. Furthermore, the study of microglia at the transcriptional and epigenetic levels has enhanced our knowledge of these native brain immune cells. Moreover, exploring various facets of microglia biology will facilitate the early detection, treatment, and management of neurological disorders. Consequently, the present review aimed to provide comprehensive insight on microglia biology and its influence on brain development, homeostasis, management of disease, and highlights microglia as potential therapeutic targets in neurodegenerative and neurodevelopmental diseases.

Analysis of SET and MYND Domain-Containing Protein 3 (SMYD3) Expression in Gallbladder Cancer: a Pilot Study.

The Suvar, Enhancer of zeste, and Trithorax (SET) and myeloid-Nervy-DEAF-1 (MYND) domain-containing protein 3 (SMYD3) is a histone lysine methyltransferase and has been recently unveiled to play significant roles in the progression of human cancer via regulating various key cancer-associated genes and pathways. The role of SMYD3 in gallbladder cancer (GBC) still needs to be studied. In the present study, we examined the SMYD3 gene expression at mRNA and protein level to look its impact on risk for developing gallbladder carcinogenesis. SMYD3 expression was evaluated by immunohistochemistry and reverse transcriptase PCR (RT-PCR) from 30 cases each of GBC and cholelithiasis patients. The expression was compared with different clinicopathological parameters. The SMYD3 expression was found to be significantly upregulated in GBC than cholelithiasis group (p < 0.05). The SMYD3 with increased expression level was observed in 73.3% of the GBC cases (p < 0.05). Moreover, mRNA SMYD3 expression was observed in 73.3% of GBC and 10% of control (p < 0.05). Our results indicated that the overexpression of SMYD3 plays an important role in the GBC progression, and SMYD3 may represent useful biomarker for gallbladder cancer patients.

Microglia Specific Drug Targeting Using Natural Products for the Regulation of Redox Imbalance in Neurodegeneration.

Microglia, a type of innate immune cell of the brain, regulates neurogenesis, immunological surveillance, redox imbalance, cognitive and behavioral changes under normal and pathological conditions like Alzheimer's, Parkinson's, Multiple sclerosis and traumatic brain injury. Microglia produces a wide variety of cytokines to maintain homeostasis. It also participates in synaptic pruning and regulation of neurons overproduction by phagocytosis of neural precursor cells. The phenotypes of microglia are regulated by the local microenvironment of neurons and astrocytes via interaction with both soluble and membrane-bound mediators. In case of neuron degeneration as observed in acute or chronic neurodegenerative diseases, microglia gets released from the inhibitory effect of neurons and astrocytes, showing activated phenotype either of its dual function. Microglia shows neuroprotective effect by secreting growths factors to heal neurons and clears cell debris through phagocytosis in case of a moderate stimulus. But the same microglia starts releasing pro-inflammatory cytokines like TNF-α, IFN-γ, reactive oxygen species (ROS), and nitric oxide (NO), increasing neuroinflammation and redox imbalance in the brain under chronic signals. Therefore, pharmacological targeting of microglia would be a promising strategy in the regulation of neuroinflammation, redox imbalance and oxidative stress in neurodegenerative diseases. Some studies present potentials of natural products like curcumin, resveratrol, cannabidiol, ginsenosides, flavonoids and sulforaphane to suppress activation of microglia. These natural products have also been proposed as effective therapeutics to regulate the progression of neurodegenerative diseases. The present review article intends to explain the molecular mechanisms and functions of microglia and molecular dynamics of microglia specific genes and proteins like Iba1 and Tmem119 in neurodegeneration. The possible interventions by curcumin, resveratrol, cannabidiol, ginsenosides, flavonoids and sulforaphane on microglia specific protein Iba1 suggest possibility of natural products mediated regulation of microglia phenotypes and its functions to control redox imbalance and neuroinflammation in management of Alzheimer's, Parkinson's and Multiple Sclerosis for microglia-mediated therapeutics.

Cyanobacterial bioactive compound EMTAHDCA recovers splenomegaly, affects protein profile of E. coli and spleen of lymphoma bearing mice.

The antibacterial and anticancerous properties of EMTAHDCA have already been reported in our previous study. However, mode of action of EMTAHDCA is still elusive. The present study was aimed to investigate the molecular targets in Escherichia coli and spleen of lymphoma-bearing mice in response to cyanocompound 9-ethyliminomethyl-12 (morpholin-4-ylmethoxy)-5, 8, 13, 16-tetraaza -hexacene-2, 3- dicarboxylic acid (EMTAHDCA) isolated from fresh water cyanobacterium Nostoc sp. MGL001. Differential expressions of proteins were observed in both E. coli and spleen of lymphoma-bearing mice after EMTAHDCA treatment. In continuation of our previous study, the present study revealed that the antibacterial agent, EMTAHDCA causes the drastic reduction in synthesis of proteins related to replication, transcription, translation and transportation in E. coli. Probably the direct or indirect interaction of this compound with these important metabolic processes led to the reduction in growth and cell death. Furthermore, the anticancerous property of the compound EMTAHDCA reflected as down regulation in proteins of cell cycle, cellular metabolism, signalling, transcription and transport together with up regulation of apoptosis, DNA damage and immunoprotection related proteins in spleen of lymphoma-bearing mice. In this study the EMTAHDCA induced modulations in expression of proteins of key metabolic pathways in E. coli and spleen cells of lymphoma bearing mice helped in understanding the mechanism underlying the antibacterial and anti-cancerous property.

Age-dependent alterations in expression and co-localization of Pax6 and Ras-GAP in brain of aging mice.

As the brain ages, the survival and plasticity of neurons and glia are compromised. The data-mining and in silico studies suggest interactions of Pax6 with Ras and binding sites in Ras-GAP promoter. The Pax6 also shows age-dependent alterations. Therefore, it is presumed that Pax6 may be associated with the Ras-GAP, a synaptic protein, either directly or indirectly in brain. The expression, co-localization and interaction of Pax6 and Ras-GAP in different regions of brain of mice during aging were investigated through immunofluorescence assay, co-immunoprecipitation and western blotting, respectively. The co-localization of Pax6 and Ras-GAP were observed in dentate gyrus (DG) and sub-granular zone (SGZ) of hippocampus, in glomerular (GlLa) and mitral cells (MiCe) of olfactory lobe, granular cells (GrCe), Purkinje cell (PuCe) and molecular cell layer (MoLa) of cerebellum, internal plexiform layer (InPl), molecular layer (MoLa) of cerebral cortex and in intercalated cells of amygdala (ITC), caudate nucleus regions in brain of aging mice. The expression of Pax6 and Ras-GAP was altered in hippocampus, amygdala, caudate nucleus, olfactory lobe, cerebral cortex and cerebellum from young to old mice. The Pax6 interacts with Ras-GAP in brain of mice. Results indicate impact of Pax6 on Ras-GAP-mediated activities of synapses, learning and memory, emotions and fear as well as motor functions. Alterations in expression and co-localization of Pax6 and Ras-GAP during aging may be responsible for age-associated compromised survival and plasticity of neurons and glia.

Level of hydrogen peroxide affects expression and sub-cellular localization of Pax6.

The Pax6 is a multifunctional pairedbox and homeobox containing transcription factor which is involved in several functions of brain, eyes, and pancreas. It regulates expression of genes involved in cell proliferation, differentiation, inflammation, oxidative stress management, and neuropathy. Dynamic changes in the sub-cellular localization of Pax6 are proposed to regulate its activity, however, the underlying mechanism remains poorly understood. The oxidative stress mediated changes were studied in sub-cellular localization of Pax6 in cultured cells derived from the eye (cornea) and pancreas. The impact of induced oxidative stress was investigated on reactive oxygen species scavenger molecules, Superoxide dismutase1 (SOD1) and Catalase, and a critical cell signalling molecule Transforming growth factor-beta (TGF-ß1). The cells were treated with three different concentrations of H2O2, viz., 0.3, 1.5, and 3.0 mM. The cell viability was analysed through Trypan blue dye exclusion assay. The localization of Pax6 was observed by immunofluorescence labeling, and alterations in levels of Pax6, SOD1, Catalase, and TGF-ß1 were investigated by semi-quantitative RT-PCR. Nucleo-cytoplasmic shuttling of Pax6 was observed in cells of corneal epithelial (SIRC) and pancreatic origins (MIA-PaCa2). The percentage distribution of Pax6 in nuclear and cytoplasmic compartments of SIRC and MIA-PaCa2 cells was analyzed through ImageJ software. Level of hydrogen peroxide affects expression and sub-cellular localization of Pax6. Expression of Pax6 and TGF-ß1 are directly associated with changes in sub-cellular localization of Pax6 and modulation in expression of Catalase. This may be the result of a cellular protective mechanism against peroxide-dependent cellular stress.

Co-Localization and Interaction of Pax5 with Iba1 in Brain of Mice.

The Pax5, a B-cell-Specific Activator Protein (BSAP) and redox-sensitive transcription factor, is expressed in the immune-privileged brain, B-lymphocytes, lymph nodes and spleen. PAX5-mediated immune pathway has also been described in the progression of Glioblastoma multiforme. However, the status of Pax5 and its role in brain immunity are not yet elucidated. In silico analysis of Pax5 interacting proteins predicts its interaction with proteins of cell proliferation, differentiation of hematopoietic cells, neurogenesis and several cell signalling pathways. Promoter analysis shows multiple binding sites for Pax5 in promoter of ionized calcium-binding adapter molecule 1 (Iba1). Like Iba1, Pax5 is also associated with inflammatory and immune response, activation of leukocyte and remodelling of actin cytoskeleton. Therefore, localization and interaction of Pax5 with Iba1 in brain of mice were studied using Chromatin Immunoprecipitation (ChIP), Co-Immunoprecipitation (Co-IP) and Immuno-fluorescence assay. The Pax5- and Iba1-positive cells were observed in cerebral cortex, cerebellum, olfactory bulb, hippocampus, and ventricles of brain. The co-localization of Pax5 and Iba1 was evident in microglia in almost all evaluated regions of brain. In some regions, Pax5- and Iba1-positive were distinctly compartmentalized. The Pax5a/b interacts with Iba1 and binds to its regulatory sequences. Results indicate Pax5-associated activities of Iba1 in microglia in brain of mice.

The Combined Use of in Silico, in Vitro, and in Vivo Analyses to Assess Anti-cancerous Potential of a Bioactive Compound from Cyanobacterium Nostoc sp. MGL001.

Escalating incidences of cancer, especially in developed and developing countries, demand evaluation of potential unexplored natural drug resources. Here, anticancer potential of 9-Ethyliminomethyl-12-(morpholin-4-ylmethoxy)-5,8,13,16-tetraaza -hexacene-2,3-dicarboxylic acid (EMTAHDCA) isolated from fresh water cyanobacterium Nostoc sp. MGL001 was screened through in silico, in vitro, and in vivo studies. For in silico analysis, EMTAHDCA was selected as ligand and 11 cancer related proteins (Protein Data Bank ID: 1BIX, 1NOW, 1TE6, 2RCW, 2UVL, 2VCJ, 3CRY, 3HQU, 3NMQ, 5P21, and 4B7P) which are common targets of various anticancer drugs were selected as receptors. The results obtained from in silico analysis showed that EMTAHDCA has strong binding affinity for all the 11 target protein receptors. The ability of EMTAHDCA to bind active sites of cancer protein targets indicated that it is functionally similar to commercially available anticancer drugs. For assessing cellular metabolic activities, in vitro studies were performed by using calorimetric assay viz. 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT). Results showed that EMTAHDCA induced significant cytotoxic response against Dalton's lymphoma ascites (DLA) cells in a dose and time dependent manner with an inhibitory concentration (IC50) value of 372.4 ng/mL after 24 h of incubation. However, in case of normal bone marrow cells, the EMTAHDCA did not induce cytotoxicity as the IC50 value was not obtained even with higher dose of 1,000 ng/mL EMTAHDCA. Further, in vivo studies revealed that the median life span/survival days of tumor bearing mice treated with EMTAHDCA increased significantly with a fold change of ~1.9 and 1.81 corresponding to doses of 5 and 10 mg/kg body weight (B.W.) of EMTAHDCA respectively, as compared to the DL group. Our results suggest that 5 mg/kg B.W. is effective since the dose of 10 mg/kg B.W. did not show any significant difference as compared to 5 mg/kg B.W. Taken together, our findings based on in silico, in vitro, and in vivo analyses suggest that EMTAHDCA has potential anticancer effects, and thus, can be considered for cancer treatment.

Pax6 Binds to Promoter Sequence Elements Associated with Immunological Surveillance and Energy Homeostasis in Brain of Aging Mice.

BACKGROUND: Patients having mutations of Pax6 bear phenotypes that match age-associated neurological disorders. Mutations affect most cellular functions such as cell division, growth, differentiation, and cell death in brain, eyes, pituitary, pineal, and pancreas. The progressive reduction in the level of Pax6 during aging has also been observed. However, information about downstream targets of Pax6 in brain is unclear. Therefore, it is presumed that age-dependent alterations of Pax6 may also affect cascades of promoter sequence recognition in brain during aging. PURPOSE: This study is aimed at studying the interaction of Pax6 with DNA sequence elements to explore alteration in gene targets and transcription networks of Pax6 in brain during aging. METHODS: Chromatin immunoprecipitation with anti-Pax6 using tissue extracts of brain from newborn, young, adult, and old mice was done. Pulled DNA from brain was analysed by gene-specific polymerase chain reaction (PCR). Amplified PCR products were sequenced and analyzed. RESULTS: Age-associated alterations in binding to genetic sequence elements by Pax6 were observed. Promoter analysis predicts genes involved in neuronal survival (Bdnf, Sparc), specificity of astrocyte (S100ß, Gfap), cell-proliferation (Pcna), inflammation and immune response (interferon-γ, tumour necrosis factor-α), management of oxidative stress (Sod, Cat), and hypoxia (Ldh). CONCLUSION: The Pax6 either directly or indirectly binds to promoter sequences of genes essential for immunological surveillance and energy metabolism in brain that alters during aging.

Pax6 interacts with Iba1 and shows age-associated alterations in brain of aging mice.

The Pax6, a transcriptional regulator and multifunctional protein, has been found critical for neurogenesis, neuro-degeneration, mental retardation, neuroendocrine tumors, glioblastoma and astrocytomas. The age-associated alteration in the expression of Pax6 in neuron and glia has also been observed in the immunologically privileged brain. Therefore, it is presumed that Pax6 may modulate brain immunity by activation of microglia either directly interacting with genes or proteins of microglia or indirectly though inflammation associated with neurodegeneration. This report describes evaluation of expression, co-localization and interactions of Pax6 with Ionized binding protein1 (Iba1) in brain of aging mice by Immunohistochemistry, Chromatin Immuno-precipitation (ChIP) and Co-immunoprecipitation (Co-IP), respectively. The co-localization of Pax6 with Iba1 was observed in the cerebellum, cerebral cortex, hippocampus, midbrain and olfactory lobe. The Pax6 and Iba1 also interact physically. The age-dependent alteration in their expression and co-localization were also observed in mice. Results indicate Pax6-dependent activities of Iba1 in the remodelling of microglia during immunological surveillance of the brain.

Tolerance of hyperammonemia in brain of Heteropneustes fossilis is supported by glutamate-glutamine cycle.

This report presents analysis of molecular switches associated with tolerance to hyperammonemia in Heteropneustes fossilis because it tolerates about 100-fold more ammonia than mammals. Brains of Heteropneustes fossilis exposed to 100mM ammonium chloride were dissected after Zero hour as control, 16h and 20h exposure. The status of neuron and glia were analysed by Golgi staining, Luxol Fast Blue, and Nissl's staining. The expression patterns of genes associated to homeostasis of neuron and glia, management of oxidative stress and inflammation, ammonia metabolism and brain derived neurotrophic factor were analysed through reverse-transcriptase-polymerase chain reaction. After 20h of hyperammonemia glia were more degenerated than neurons. The expression of mRNA of lactate dehydrogenase (Ldh), super oxide dismutase (Sod), catalase (Catalase), arginase-I (Arg I), inducible nitric oxide (iNos), glutaminase (GA), and brain derived neurotrophic factor (Bdnf) was up-regulated than the control. The levels of mRNA of Arg II, glutamate dehydrogenase (Gdh), glutamine synthetase (GS), glial fibrillary acidic protein (Gfap), proliferating cell nuclear antigen (Pcna) and S100ß were down-regulated than control due to hyperammonemia. It appears first observation on impact of hyperammonemia on the status of neurons, myelination and glial cells in brain of Heteropneustes fossilis by Golgi staining, Nissl's and Luxol Fast Blue staining. The distribution of ammonia and glutamate metabolising enzymes in brain supports multi-centric mechanism (s) of regulation. The expression of Arg I and Arg II gets inversely regulated and glutamate-glutamine cycle also operates in Heteropneustes fossilis against hyperammonemia in brain.