Impaired expression of testicular androgen receptor and collagen fibers in the testis of diabetic rats under HAART: the role of Hypoxis hemerocallidea

摘要

Introduction. Wide spectrum of alterations associated with highly active antiretroviral therapy (HAART) has been reported. The current study aimed at evaluating the role of Hypoxis hemerocallidea (HH) aqueous extract on the testosterone levels, expression of androgen receptors and collagen fibers in the testes of streptozotocin-nicotinamide-induced diabetic rats under HAART regimen. Material and methods. Sixty two adult male Sprague-Dawley rats (189.0 ± 4.5 g) were divided into eight groups (8 animals in each treatment groups and 6 rats in the control group). Diabetes was induced by a single intraperitoneal injection of nicotinamide (110 mg/kg bw) followed by streptozotocin (45 mg/kg bw) and the animals were then subjected to various treatments with HAART, HH extract or melatonin. At the end of the experiment, blood samples were collected to measure serum testosterone levels. Testes were fixed in buffered formaldehyde and paraffin processed. The expression of androgen receptor (AR) was assessed by immunohistochemistry and collagen fibers were visualized by Masson trichrome staining. Results. Serum testosterone level was drastically (p < 0.0001) reduced in all rats with induced diabetes. In the testis of diabetic rats increased collagen fibers deposition with varying derangements in germinal epithelium of spermatogenic layers were observed. Intertubular hemorrhages and absence of spermatozoa were also noted in the testes of diabetic rats subjected to HAART. Reduced immunoexpression of ARs was found in the nuclei of Sertoli cells and the cytoplasm of spermatogonia and spermatocytes in III–IV stages of the seminiferous epithelium cycle of diabetic animals treated with different dosages of HH alone and those treated with HAART concomitantly with melatonin and HH. The expression of ARs was almost negative in the testes of rats treated with HAART alone. Conclusions. Concomitant treatment of rats with aqueous HH extract during the HAART did not change serum testosterone level nor mitigate the altered expression of collagen fibers and androgen receptor resulting from STZ-nicotinamide-induced diabetes. Therefore, anti-diabetic properties of Hypoxis extract require further investigation.