Interactions of alcohol and combination antiretroviral (cART) drug in diabetic male Sprague Dawley rats: Hippocampal perturbations and toxicosis.

Hippocampal pathology in diabetes is constantly investigated but the resultant health impact of the concomitant presence of alcohol and combined antiretroviral therapy (cART) in diabetes requires further studies to delineate toxicities inimical to hippocampal normal function. Forty-eight male Sprague Dawley rats were divided into eight groups (n = 6): negative control (NC), alcohol (AL), cART (AV), alcohol-cART (AA), diabetic control (DB), diabetes-alcohol (DAL), diabetes-cART (DAV), and diabetes-alcohol-cART (DAA) exposure groups. Following diabetes induction and sub-chronic (90 days) treatment exposure, hippocampal homogenates were profiled for pro-inflammatory cytokines and oxidative stress (MDA and GPx) using immunoassay, while apoptotic genes (BAX, Bcl2, and Caspase-3), insulin receptor genes (INSR and IRS-1), and blood-brain barrier (BBB) junctional proteins (claudin-5, and occludin) gene expression were assessed using qPCR. Histomorphology of hippocampal neuronal number, nuclei area, and volume of dentate gyrus and neurogenesis were accessed using Giemsa stain, Ki67, and DCX histochemistry respectively. A central hippocampal effect that underpins all treatments is the reduction of DG neuronal number and antioxidant (GPx), highlighting the venerability of the hippocampal dentate gyrus neurons to diabetes, alcohol, cART, and their combinatorial interactions. Additionally, elevated BAX, Bcl2, and IRS1 mRNA levels in the DAL group, and their downregulation in AA, suggests IRS-1-regulated apoptosis due to differential modulating effects of alcohol treatment in diabetes (DAL) in contrast to alcohol with cART (AA). Although the interaction in AA therapy ameliorated the independent alcohol and cART effects on MDA levels, pro-inflammatory cytokines, and DCX, the interaction in AA exacerbated a deficiency in the expression of INSR, IRS-1 (insulin sensitivity), and BBB mRNA which are implicated in the pathogenies of diabetes. Furthermore, the diabetic comorbidity groups (DAV, DAL, and DAA) all share a central effect of elevated hippocampal oxidative stress, BAX, and Caspase-3 mRNA expression with the reduced number of hippocampal neurons, dentate gyrus volume, and neurogenesis, highlighting neurodegenerative and cognitive deficiency implication of these comorbidity treatments. Considering these findings, assessment of hippocampal well-being in patients with these comorbidities/treatment combinations is invaluable and caution is advised particularly in alcohol use with cART prophylaxis in diabetes.

Combination Antiretroviral Therapy (cART) in Diabetes Exacerbates Diabetogenic Effects on Hippocampal Microstructure, Neurogenesis and Cytokine Perturbation in Male Sprague Dawley Rats.

The increasing incidence of diabetes and HIV/AIDS-diabetes comorbidity in society has led to the prevalence of combination antiretroviral therapy (cART) in diabetes, with some reported neural effects. Therefore, the effects of cART and type two diabetes (T2D) on the hippocampal levels of cytokines, lipid peroxidation; histomorphology and neurogenesis were investigated. Adult male Sprague-Dawley rats were divided into four groups: DB (diabetic rats); DAV (diabetic rats treated with cART (efavirenz, emtricitabine and tenofovir); AV (normal rats treated with cART) and the NC group (with no treatment). Following ninety days of treatment, the rats were terminated, and the brains excised. Immunoassay (IL-1α, IL-6, TNFα and MDA); immunohistochemical (Ki67 and DCX) and cresyl violet histomorphology analyses were carried out on brain homogenates and sections, respectively. In comparison to the control, the results showed that cART significantly elevated the IL-6, TNFα and MDA levels, while DB and DAV significantly reduced the body weight, glucose tolerance, IL-1α, IL-6, TNFα and MDA levels. The hippocampal neuronal number was reduced in AV (dentate gyrus; DG region), in the DB group (Cornu Ammonis subregion 1; CA1 and DG regions only) and in DAV (all three hippocampal regions). Additionally, the expression of neurogenic markers Ki67 and doublecortin (DCX) were reduced in the diabetic group, with a greater reduction in the cART+T2D group compared to the control. Furthermore, the neuronal number at all hippocampal regions was negatively corelated with the diabetic parameters (FBG; fasting blood glucose, NFBG; non-fasting blood glucose, AUC; area under the glucose tolerance curve) but positively correlated with body weight. Additionally, the increase in the DG neuronal nuclei area of DB and DAV was significantly positively correlated with FBG, NFBG and AUC and inversely correlated with the estimated number of neurons and neurogenesis. These findings indicate that cART in diabetes (DAV) has similar effects as diabetes relative to the induction of oxidative stress and impairment of the cytokine immune response, but exacerbated neurotoxicity is observed in DAV, as shown by a significantly decreased DCX expression compared to DB and reduction in the number of Cornu Ammonis subregion 3 (CA3) hippocampal neurons, unlike in cART or the diabetes-alone groups.

Cardiotoxicity in African clawed frog (Xenopus laevis) sub-chronically exposed to environmentally relevant atrazine concentrations: Implications for species survival.

The toxic effects of different atrazine concentrations on tadpoles and adult male African clawed frogs (Xenopus laevis) were assessed in a controlled laboratory environment following 90 days' exposure. The aim was to elucidate the danger of atrazine exposure on the cardiac tissue relative to its critical function of rhythmic contractility, fundamental for optimal blood circulation and homeostasis. Tadpoles and adult frogs were exposed to 0 µg/L (control), 0.01 µg L-1, 200 µg L-1 and 500 µg L-1 concentrations of atrazine for 90 days. Mortality was concenration-dependent and significantly increased in juvenile group (77%, 43%, 23% and 0 respectively for 500 µg L-1, 200 µg L-1, 0.01 µg L-1, and control group). While the mean juvenile heart area decreased concentration-dependently, adult frog mean heart area significantly increased in the 200 µg L-1 group only and mean heart weight change was variable across all exposure levels. Light microscopy of hematoxylin and eosin (H&E) and Mallory-Heidenhain rapid one-step staining techniques on cardiac tissue sections of the juvenile and adult frogs revealed shrinkage of cardiac muscle cells into thin wavy myocytes. Additionally, disorganized branching of muscle fibres with reduced striations were observed in 0.01 µg L-1 and 200 µg L-1 but hypertrophied myocytes, thickened intensely staining myofibrils in the 500 µg L-1 group in juvenile and adult frogs. Significant increase in the mean percentage area of connective tissue in all the treated groups (p < 0.036) were also recorded. Immunohistochemistry analysis showed decreased eNOS localization in cardiac tissue in 200 µg L-1 and 500 µg L-1 of both juvenile and adult group, suggestive of decreased cardiac contractility due to atrazine exposure. The results indicate that environmentally relevant atrazine concentrations cause significant mortality in tadpoles while concentrations ≥200 µg L-1 adversely affect cardiac muscle morphology and may induce functional perturbations in cardiac tissue contractility and consequent dysfunction which generally may have an adverse impact on their survival and longevity.