Effects of Rooibos (Aspalathus linearis) on the Testicular Parenchyma of Adult BALB/C Mice Submitted to a Hypercaloric Diet

Oxidative stress due to obesity plays a detrimental role in the testicular microenvironment and sperm parameters. We explored the impact of a hypercaloric diet in male BALB/c mice as a condition to trigger damage to the spermatogenic process and the antioxidant effect of Aspalathus linearis as well. We used a hypercaloric diet in animals divided into 3 groups: Control, Hypercaloric diet control (HC) and Hypercaloric diet and Rooibos infusion (HCR). Morphometric parameters, enzyme dosages, cell viability, and tubular histopathology were evaluated. Body weight increased in HCR animals at weeks 3, 4, and 8. We found a reduction in seminiferous epithelium height, with an increase in the tubular diameter of the HCR group. Catalase levels were lower in HC and HCR, while carbonyl protein was decreased in HC. We estimate that it induces oxidative stress (OS) capable of affecting the seminiferous epithelium and that the infusion of A. linearis does not demonstrate a potential benefit in cell preservation.

The effectiveness of insulin therapy in the functional and morphological recovery of leydig cells in rats submitted to Diabetes mellitus

The effects of systemic insulin administration at different concentrations on the testicular tissue of diabetic adult rats, induced by streptozotocin, are evaluated by the morphological analysis of spermatogenic process. Twenty-four adult male rats were divided into 1) Control Group: they received citrate buffer, by intraperitoneal injection; 2) Diabetic Group: induced by intraperitoneal injection of streptozotocin (60 mg. kg-1 of body weight); 3) Insulin 50%: induced diabetes treated with half of standard dosage of insulin; 4) Insulin 100%: induced diabetes treated with standard dose of insulin. After eight weeks, animals were weighted and anesthetized; testicles were removed and processed in resin. Body and testicular weight of diabetic rats decreased when compared to that of control. Parameters increased with insulin therapy. Testosterone levels were low in diabetic animals but rates recovered after insulin therapy. Nuclear diameter and volume of Leydig cells decreased in diabetic rats although they significantly increased after insulin therapy. Results showed that the administration of insulin in diabetic rats promoted a protective effect of testicular parenchyma, enhancing efficient recovery on testosterone levels and increase in daily sperm production.

Comparison of the spermatogenic process in three different mice strains: Swiss, Balb/C and C57BL/6

Many studies have been trying to establish standard protocols for animal experimentation, especially for animal species or strains, to master research variables with high precision. The main mouse strains used in the field of the biology of reproduction are Swiss, Balb/c, and C57BL/6. Since some of the strains show reproduction limitations, such as the size of the litter, the present study aimed to compare their spermatogenic processes to verify differences regarding the testicular parenchyma and germ cell populations, which could explain low offspring production. In addition, the present study provides additional information concerning the testicular parenchyma of such strains, which consequently would help researchers to choose the most suitable strain for reproductive studies. Six adult male mice were used for each of the strains. After euthanasia, the testes were weighed, fixated with Karnovsky fixative, embedded in methacrylate, sectioned, and stained with toluidine blue/sodium borate 1%. Morphometrical analyses from the testicular parenchyma (seminiferous tubules and interstitium) were made using the software ImageJ. Germ and Sertoli cells populations were counted in seminiferous tubules cross-sections at stage I of the seminiferous epithelium cycle. The lowest body and testicular weights were observed in C57BL/6 animals, followed by Balb/c and Swiss, however, the relative testes, parenchyma, and albuginea weights were significantly lower only in C57BL/6. Despite the seminiferous tubules and seminiferous epithelium proportions were lower in Swiss animals, their relative amount related to the body weight was the same among strains. The total number of germ cells was higher in Swiss animals, reflecting higher spermatogenic yield and daily sperm production. Due to the lower relative number of Sertoli cells, the Swiss animals showed the highest Sertoli cell index and support capacity. On the other hand, the lowest pathological indexes regarding the germ cells were observed in Balb/c animals, followed by Swiss and C57BL/6. In the interstitium, the proportion of blood vessels was lower in Swiss mice, while the lymphatic cell proportion was lower in C57BL/6 animals. Moreover, the highest proportions of Leydig cells and macrophages were noticed in Swiss mice, which may indicate increased testosterone levels. Altogether, such observations must be taken into account when choosing any of the studied strains for reproduction studies.