Apoptosis in testicular germ cells

Spirulina platensis (Arthrospira platensis) attenuates Cyclophosphamide-induced reproductive toxicity in male Wistar rats: Evidence for sperm apoptosis and p53/Bcl-2 expression

Cyclophosphamide is an antitumor agent that causes disorders in fertility. This study aimed to evaluate the protective effects of Spirulina platensis against Cyclophosphamide-induced testicular toxicity. 42 male Wistar rats were randomly divided into six groups. Experimental groups included three groups. The first experimental group received Cyclophosphamide at a dose of 5 mg/kg body weight (BW) orally. The second and third experimental groups received 5 mg/kg BW Cyclophosphamide and 500 and 1,000 mg/kg BW S. platensis orally, respectively. The control groups included a control group, and two S. platensis control groups. Following 28 days, two flow cytometry techniques were used to determine sperm apoptosis and testicular protein expression of tumor protein (p53) and B-cell lymphoma 2 (Bcl-2). p53 is a tumor suppressor protein that causes the cell to enter the apoptosis cycle after DNA damage and Bcl-2 is an anti-apoptotic protein that acts through the mitochondrial pathway of apoptosis. FITC-Annexin V assay was used for sperm apoptosis evaluation. For protein expression assay, primary and secondary antibodies staining were performed. The Cyclophosphamide group showed a significant increase in sperm apoptosis compared to the control group. Cyclophosphamide significantly increased p53 and decreased Bcl-2 expression compared to the control group. S. platensis co-treated groups exhibited a significant decrease in sperm apoptosis compared to the Cyclophosphamide group. Moreover, S. platensis co-treated groups displayed a significant decreasing in p53 and increasing in Bcl-2 expression compared to the Cyclophosphamide group. The results of this study indicated that S. platensis protected rats against Cyclophosphamide-induced reproductive toxicity. PRACTICAL APPLICATIONS: Cyclophosphamide is the chemotherapy agent used to treat different cancers. Cyclophosphamide has side effects on the male reproductive system. Spirulina plantesis has a protective effect because of its antioxidant and anti-apoptotic properties. Co-administration of Spirulina plantesis with Cyclophosphamide reduces sperm apoptosis also decreases P53 protein expression and increases Bcl-2 protein expression. This study validated the anti-apoptotic potential of Spirulina plantesis against Cyclophosphamide-induced male reproductive toxicity.

Histochemical Study of the Emergence of Apoptosis and Altered SYCP3 Protein Distribution During the First Spermatogenic Wave in Wistar Rats

Apoptosis is a type of cell death responsible for maintaining tissue homeostasis that can occur in male gonads. The morphological and biochemical characteristics of apoptosis include cellular contraction, caspase activation, and DNA fragmentation. Dynamic processes of cell renewal and differentiation occur inside the seminiferous tubules, which are regulated by mitosis and meiosis, respectively. During meiosis, recombination is caused by assembly of the synaptonemal complex, which involves the participation of constitutive proteins, such as synaptonemal complex protein-3 (SYCP3). The present study evaluated germinal cell death in immature male rats and the distribution of the SYCP3 protein. Our results indicate that as germinal cells progress to the second meiotic stage, significant numbers of them are eliminated by apoptosis. We determined that the SYCP3 protein is not always incorporated into the structure of the synaptonemal complex but rather forms a nuclear cumulus near the inner nuclear membrane, causing many of these cells to undergo apoptosis. We propose that both the excess of the SYCP3 protein and its accumulation during the first meiotic division could contribute to the cell death of primary spermatocytes during the first spermatogenic wave in prepubertal Wistar rats. Anat Rec, 302:2082-2092, 2019. © 2019 American Association for Anatomy.

Yangjing Capsule Ameliorates Spermatogenesis in Male Mice Exposed to Cyclophosphamide

Yangjing capsule (YC), a traditional Chinese compound herbal preparation, has been proven as an effective drug to improve spermatogenesis in clinical practice. However, its pharmacological mechanisms were not fully clarified. This study was designed to investigate the protective effects of YC on spermatogenesis in the mouse model of spermatogenesis dysfunction induced by cyclophosphamide (CP). The administration of YC significantly increased the epididymal index, sperm count, and sperm motility of model mice. Histopathological changes demonstrated that CP caused obvious structural damage to testis, which were reversed by the administration of YC. Results from TUNEL assay showed that treatment with YC dramatically decreased the apoptosis of spermatogenic cell induced by CP. Moreover, YC treatment could inhibit the mRNA and protein expression of Bax to Bcl-2 and also raised expression of AR at both mRNA and protein levels. These data suggest that YC might ameliorate spermatogenesis in male mice exposed to CP through inhibiting the apoptosis of spermatogenic cell and enhancing the actions of testosterone in spermatogenesis.

Apoptotic changes in the epithelium germinativum of the cat (Felis catus s. domestica, L. 1758) at different ages and breeding seasons

Apoptosis (programmed cell death) could be considered as a physiological process that takes part in a healthy organism, which helps to maintain organism homeostasis. The visible deterioration of semen quality and the number of germ cells is accompanied by a seasonal decrease of the reproductive activity in some species. This post-effect cascade is caused by apoptosis, which is the primary mechanism responsible for the elimination of germ cells during spermatogenesis. The aim of our study was to assess apoptotic changes in the epithelium germinativum in cat testes at different ages. One hundred and two pairs of testes were obtained from domestic cats aged between 4 months and 10 years. The paraffin-embedded tissue sections were labelled using the Oncogene and Calbiochem Research Products DNA Fragmentation Detection Kit (Cat# QIA21; Darmstadt, Germany), which allows the recognition of apoptotic nuclei in tissue sections with Fragment End Labelling (FragEL) of DNA. The activity of apoptotic processes in cat testes collected from the spring-summer period compared with the autumn-winter season revealed that, 59.42% and 51.51%, respectively, males testes were characterized by insignificant changes. The obtained data revealed a distinctive apoptotic changes in the young animal testes before spermatogenesis onset. An intensification of programmed death cells in the epithelium germinativum in the elder cats (between 3-6 and 6-10 years) was not observed. Apoptotic changes slightly intensified in cats aged between 12 and 36 months.