Effects of momordica charantia on the kidney following antiretroviral therapy in male diabetic and non-diabetic animal model.

Abstract

Introduction Management of HIV/AIDS has been successful with the use of antiretroviral therapy (ART). Consequently, the introduction of highly active antiretroviral therapy (HAART) has further increased the life expectancy of people living with HIV/AIDS and this has become a standard regimen in clinical practice. However, discordant views have been reported regarding its effects on the kidney; with a dearth of literature on the impact of HAART in a diabetic comorbid state on the renal morphology and the possible role of plant-based adjuvant. This study investigated the effect of mormodica charantia (M. charantia) on the kidney following HAART regimen (triplavar) and its impact in diabetic nephropathy (DN) in streptozotocin (STZ) induced diabetic rats. Materials and Methods 78 adult male Sprague-Dawley rats were divided into non-diabetic and diabetic groups. Rat models of diabetes were successfully established by intraperitoneal injection of STZ (45 mg/kg body weight). Animals were administered an adjuvant treatment of M. charantia and HAART regimen (triplavar) according to protocols. On the 10th week, animals were euthanized with an overdose of halothane and kidney tissues were harvested and processed for light microscopy and transmission electron microscopy (TEM). Blood samples were obtained via cardiac puncture and centrifuged to collect the serums for biochemical analysis. Urine samples were collected at 3weeks interval during the 10 weeks experimental period for analysis of renal function test. Body weight and blood glucose levels (BGL) were measured once a week during the 10 weeks treatment. Results In the non-diabetic group, HAART alone treated rats showed renal dysfunction which were characterized by raised levels of blood urea nitrogen (BUN) and serum creatinine (Scr), microalbuminuria and gross electrolyte disturbances (Sodium and Potassium) as well as urea retention. Also, levels of oxidative stress (superoxide dismutase-SOD, catalase-CAT and glutathione peroxidase-GPx) were significantly decreased in these groups together with an increased levels of thiobarbituric acid reactive substances (TBARS) resulting in free radical formation via auto-oxidation. More so, the histopathological results displayed severe glomerular capillary abnormalities with inflammatory cellular infiltrations. This correlated with TEM analysis that showed swollen mitochondrial in the endothelium and thickness of the basement membrane with overexpression of extracellular matrix. Furthermore, there were upregulation of circulating neutrophil gelatinase associated lipocalin (NGAL), kidney injury molecule 1 (KIM-1) and tumor necrosis factor-alpha (TNF-α) following HAART alone treatment.

In the diabetic groups consistent raised levels of blood glucose which remained peaked from the 5th week of experiment were seen in the diabetic control and HAART treated group. There were increased levels of both BUN and Scr. Renal function test showed leakage of albumin, retention of renal electrolytes (sodium and potassium) and high concentration of urea in the urine of diabetic control and HAART treated group. Activities of antioxidative enzymes (SOD, CAT) and levels of GSH were markedly decreased with an increased level of Malondiadehyde (MDA). Significant (p<0.05) upregulation of the gene expression profiles (NGAL, KIM-1 and TNF- α) were also seen. Qualitative light microscopic result using hematoxylin and eosin (H and E) stains showed glomerular capillary abnormalities and tubular epithelial damage. These findings correlated with other special stains (PAS and MT) which showed high proportion of glycogen, glycoproteins as well as mild deposition of collagen fibers and hyaline substances respectively. TEM analysis displayed an abnormally increased thickness of basement membrane which reflects the existence of endothelial damage (diabetic control). By contrast, following adjuvant treatment with M. charantia, (low and high dose) these abnormalities were significantly reduced thus suggesting a protective effect of M. charantia on the kidney. Conclusion M. charantia extract administration improved blood glucose levels, maintained renal electrolytes (Sodium and Potassium), reinstated renal function (BUN and Scr) restored histoarchitectural and ultrastructural patterns and prevented DN development in an STZ-induced diabetic rat model. Keywords: HAART, Nephrotoxicity, Diabetic nephropathy, TEM, M. charantia, Sprague-Dawley rats, Histoarchiteture