The potential of sertoli cells (SCs) derived exosomes and its therapeutic efficacy in male reproductive disorders.

In the male reproductive system, seminiferous tubules in testis are lined by a complex stratified epithelium containing two distinct populations of cells, spermatogenic cells that develop into spermatozoa, and sertoli cells (SCs) that mainly support and nourish spermatogenic cell lineage as well as exerting powerful effect on men reproductive capacity. Different varieties of proteins, hormones, exosomes and growth factors are secreted by SCs. There are different kinds of junctions found between SCs called BTB. It was elucidated that complete absence of BTB or its dysfunction leads to infertility. To promote spermatogenesis, crosstalk of SCs with spermatogenic cells plays an important role. The ability of SCs to support germ cell productivity and development is related to its various products carrying out several functions. Exosomes (EXOs) are one of the main EVs with 30-100 nm size generating from endocytic pathway. They are produced in different parts of male reproductive system including epididymis, prostate and SCs. The most prominent characteristics of SC-based exosomes is considered mutual interaction of sertoli cells with spermatogonial stem cells and Leydig cells mainly through establishment of intercellular communication. Exosomes have gotten a lot of interest because of their role in pathobiological processes and as a cell free therapy which led to developing multiple exosome isolation methods based on different principles. Transmission of nucleic acids, proteins, and growth factors via SC-based exosomes and exosomal miRNAs are proved to have potential to be valuable biomarkers in male reproductive disease. Among testicular abnormalities, non-obstructive azoospermia and testicular cancer have been more contributed with SCs performance. The identification of key proteins and miRNAs involved in the signaling pathways related with spermatogenesis, can serve as diagnostic and regenerative targets in male infertility.

The guardians of germ cells; Sertoli-derived exosomes against electromagnetic field-induced oxidative stress in mouse spermatogonial stem cells.

Nowadays, prolonged exposure to electromagnetic fields (EMF) has raised public concern about the detrimental potential of EMF on spermatogonial stem cells (SSCs) and spermatogenesis. Recent studies introduced the fundamental role of Sertoli cell paracrine signaling in the regulation of SSCs maintenance and differentiation in fertility preservation. Thus we investigated the therapeutic effect of Sertoli-derived exosomes (Sertoli-EXOs) as powerful paracrine mediators in SSCs subjected to EMF and its underlying mechanisms. SSCs and Sertoli cells were isolated from neonate mice testis, and identified by their specific markers. Then SSCs were exposed to 50 Hz EMF with intensity of 2.5 mT (1 h for 5 days) and supplemented with exosomes that were isolated from pre-pubertal Sertoli cells. Sertoli-EXOs were characterized and the uptake was observed by PKH26 labeling. The cell viability, colonization efficiency, reactive oxygen species (ROS) balance, cell cycle arrest and apoptosis induction were then analysed. SSCs were confirmed by immunocytochemistry (Oct4, Plzf) and Sertoli cells were identified through Sox9 and vimentin expression by immunocytochemistry and Real-time PCR (qRT-PCR), respectively. Our results demonstrated the detrimental effect of EMF via ROS accumulation that reduced the expression of catalase antioxidant, cell viability and colonization of SSCs. Also, AO/PI and flow cytometry analysis demonstrated the elevation of apoptosis in SSCs exposed to EMF in comparison with control. qRT-PCR data confirmed the up-regulation of apoptotic gene (Caspase-3) and down-regulation of SSCs specific gene (GFRα1). Consequently, the administration of Sertoli-EXOs exerted ameliorative effect on SSCs and significantly improved these changes through the regulation of oxidative stress. These findings suggest that Sertoli-EXOs have positive impact on SSCs exposed to EMF and can be useful in further investigation of Sertoli-EXOs as a novel therapeutic agent which may recover the deregulated SSCs microenvironment and spermatogenesis after exposure to EMF.

The mechanism of neuroprotective effect of Viola odorata against serum/glucose deprivation-induced PC12 cell death.

OBJECTIVE: Oxidative stress is associated with the pathogenesis of brain ischemia and other neurodegenerative disorders. Previous researches have shown the antioxidant activity of Viola odorata L. In this project, we studied neuro-protective and reactive oxygen species (ROS) scavenging activities of methanol (MeOH) extract and other fractions isolated from V. odorata in PC12 cell line in serum/glucose deprivation (SGD) condition. MATERIALS AND METHODS: The PC12 neuronal cells were pretreated for 6 hr with MeOH extract and fractions of V. odorata (1 to 25 µg/ml) followed by 24 hr incubation under SGD condition. Cell viability was measured by Alamar Blue® assay. The level of ROS was calculated using DCFH-DA. Also, Bax/Bcl-2 protein ratio was analyzed by western blot assay. RESULTS: SGD condition significantly decreased cells viability (p<0.001). Pretreatment with EtOAc (12.5 and 25 µg/ml), BuOH (12, 25, 50 µg/ml) and CH2Cl2 (1.5 µg/ml) fractions of V. odorata reduced SGD-induced cytotoxicity. MeOH extract could not increase the viability significantly. All four semi polar fractions (EtOAc, BuOH, CH2Cl2 and MeOH) decreased SGD-induced ROS production and changed Bax/Bcl-2 ratio. CONCLUSION: V. odorata showed promising effects against SGD condition; further mechanistic and clinical studies are warranted before application of V. odorata as a neuro-protective agent.

ROS-scavenging and Anti-tyrosinase Properties of Crocetin on B16F10 Murine Melanoma Cells.

BACKGROUND: Crocus sativus (Iridaceae) has been traditionally used in the Iranian folk medicine and as a culinary additive. Major components of the plant that are responsible for biological properties are saffranal, crocin, picrocrocin and crocetin. Although the level of crocetin is not high, some of the important activities of saffron such as antioxidant activity have been attributed to crocetin. OBJECTIVE: In the present study, we investigated the effects of crocetin on melanogenesis in B16 melanoma cells. METHODS: The effect of crocetin on intracellular and mushroom tyrosinase activity and the content of melanin was evaluated spectrophotometrically. Tyrosinase and Microphthalmia-Associated Transcription Factor (MITF) protein levels were compared between Crocetin-treated and control cells after western blot analysis. The antioxidative activity of crocetin was also investigated. RESULTS: Crocetin could inhibit mushroom tyrosinase activity and lower the amount of melanin in B16 melanoma cells. Protein levels of tyrosinase and MITF were also decreased by crocetin. Crocetin also showed antioxidant activity and depleted cellular Reactive Oxygen Species (ROS) content but had no cytotoxicity in alamarBlue® assay. CONCLUSION: Taken together, decreased tyrosinase activity, melanin content, tyrosinase and MITF proteins levels, and ROS production showed the inhibition of melanogenesis in B16F10 cells by crocetin. Hence, crocetin could be suggested as a potential dermatological whitening agent in skin care products.

Inhibitory effects of different fractions of Nepeta satureioides on melanin synthesis through reducing oxidative stress.

Nepeta satureioides Boiss. has been used in traditional medicine of eastern countries and is famous for its medicinal properties. The aim of this study was to evaluate the effect of methanol (MeOH), n-hexane and dichloromethane (CH2Cl2) fractions of the extract on melanin synthesis and oxidative stress in B16F10 melanoma cell line. The B16F10 cell line viability after treatment with increasing concentrations of different fractions of the plant (5-60 µg/mL) was measured using MTT assay. The inhibitory effect on synthesis of melanin, mushroom tyrosinase activity, cellular tyrosinase and oxidative stress were determined by the colorimetric and fluorometric methods. The data showed that at concentrations below 60 µg/mL, fractions did not show significant toxicity on melanoma cells. The amount of melanin synthesis by MeOH and CH2Cl2 fractions and mushroom tyrosinase activity by the MeOH fraction declined in B16F10 cells. In addition to the capacity of MeOH, n-hexane and CH2Cl2 fractions in decreasing the amount of reactive oxygen species (ROS) in melanoma cells, all fractions revealed remarkable antioxidant activity. The melanogenesis inhibitory and antioxidant effects of N. satureioides on B16F10 cells may suggest this plant as a new pharmaceutical agent in reducing skin pigment and skin aging in cosmetic industry.