The Effect of Rooibos (Aspalathus linearis), Honeybush (Cyclopia intermedia) and Sutherlandia (Lessertia frutescens) on Testicular Insulin Signalling in Streptozotocin-Induced Diabetes in Wistar Rats

In vitro effects of aqueous extract of unfermented rooibos on human spermatozoa

The inability to conceive is a baleful experience for thousands of couples worldwide. Among different well‐known reproductive techniques, medicinal plants have been utilized to treat male infertility. Medicinal plants, provide a therapeutic alternative, which is available and affordable for infertile couples. We investigated the direct effect of unfermented rooibos aqueous extract on human spermatozoa. Semen samples (n = 50) collected from donors and patients consulting for fertility were reassigned as normal (n = 22) and abnormal (n = 28) samples based on the outcome of the baseline semen analysis, using the World Health Organization (WHO) cut off value. Semen samples were allowed to liquefy and subsequently washed with human tubular fluid in bovine serum albumin medium. The samples were then treated with aqueous extracts of unfermented rooibos (0, 0.15, 1.5, 15, 150 μg/ml) at 37°C for 1 h and assessed thereafter. Sperm motility, vitality, DNA fragmentation, intracellular reactive oxygen species and mitochondrial membrane potential in both groups remained unchanged (p > 0.05). However, aqueous extract of unfermented rooibos (only at 1.5 μg/ml) significantly increased capacitation and acrosome reaction in the abnormal sample group (p > 0.05). Unfermented rooibos aqueous extract had no deleterious impact on human spermatozoa's function and might be attributed to its antioxidant properties.

Pioglitazone Synthetic Analogue Ameliorates Streptozotocin-Induced Diabetes Mellitus through Modulation of ACE 2/Angiotensin 1–7 via PI3K/AKT/mTOR Signaling Pathway

The renin angiotensin aldosterone system has a localized key regulatory action, especially in liver and body circulation. Furthermore, it accomplishes a significant role in the downregulation of the PI3K/AKT/mTOR signaling pathway that is involved in type II diabetes mellitus pathogenesis. The current study aimed to evaluate the effect of a synthetic pioglitazone analogue (benzenesulfonamide derivative) compared to the standard pioglitazone hypoglycemic drug on enhancing liver insulin sensitivity via ACE 2/Ang (1–7)/PI3K/AKT/mTOR in experimental STZ-induced diabetes. After the model was established, rats were distributed into the normal control group, diabetic group, pioglitazone group (20 mg/kg), and a benzenesulfonamide derivative group (20 mg/kg), with the last 2 groups receiving oral treatment for 14 consecutive days. Our results suggested enhancing liver insulin sensitivity against the ACE2/Ang (1–7)/PI3K/AKT/mTOR pathway. Moreover, the synthetic compound produced a reduction in blood glucose levels, restored hyperinsulinemia back to normal, and enhanced liver glycogen deposition. In addition, it up regulated the ACE2/Ang (1–7)/PI3K/AKT/mTOR signaling pathway via increasing insulin receptor substrate 1 and 2 sensitivity to insulin, while it increased glucose transporter 2 expression in the rat pancreas. The study findings imply that the hypoglycemic effect of the benzenesulfonamide derivative is due to enhancing liver sensitivity to regulate blood glucose level via the ACE2/Ang (1–7)/PI3K/AKT/mTOR pathway.

Oxidative Stress and Male Infertility: Evidence From a Research Perspective

Male fertility potential can be influenced by a variety of conditions that frequently coincide. Spermatozoa are particularly susceptible to oxidative damage due to their limited antioxidant capacity and cell membrane rich in polyunsaturated fatty acids (PUFAs). The role of oxidative stress (OS) in the etiology of male infertility has been the primary focus of our Stellenbosch University Reproductive Research Group (SURRG) over the last 10 years. This review aims to provide a novel insight into the impact of OS on spermatozoa and male reproductive function by reviewing the OS-related findings from a wide variety of studies conducted in our laboratory, along with those emerging from other investigators. We will provide a concise overview of the production of reactive oxygen species (ROS) and the development of OS in the male reproductive tract along with the physiological and pathological effects thereof on male reproductive functions. Recent advances in methods and techniques used for the assessment of OS will also be highlighted. We will furthermore consider the current evidence regarding the association between OS and ejaculatory abstinence period, as well as the potential mechanisms involved in the pathophysiology of various systemic diseases such as obesity, insulin resistance, hypertension, and certain mental health disorders which have been shown to cause OS induced male infertility. Finally, special emphasis will be placed on the potential for transferring and incorporating research findings emanating from different experimental studies into clinical practice.