ABSTRACT
Fertility preservation and assisted reproductive medicine require effective culture systems for the successful proliferation and differentiation of spermatogonial stem cells (SSCs). Many SSC culture systems require the addition of feeder cells at each subculture, which is tedious and inefficient. Here, we prepared decellularized testicular matrix (DTM) from testicular tissue, which preserved essential structural proteins of testis. The DTM was then solubilized and induced to form a porous hydrogel scaffold with randomly oriented fibrillar structures that exhibited good cytocompatibility. The viability of SSCs inoculated onto DTM hydrogel scaffolds was significantly higher than those inoculated on Matrigel or laminin, and intracellular gene expression and DNA imprinting patterns were similar to that of native SSCs. Additionally, DTM promoted SSC differentiation into round spermatids. More importantly, the DTM hydrogel supported SSC proliferation and differentiation without requiring additional somatic cells. The DTM hydrogel scaffold culture system provided an alternative and simple method for culturing SSCs that eliminates potential variability and contamination caused by feeder cells. It might be a valuable tool for reproductive medicine.
ABSTRACT
Vitamin A (retinol) is important for multiple functions in mammals. In testis, the role of vitamin A in the regulation of testicular functions is clearly involved in rodents. It is essential for sperm production. Vitamin A deficiency adversely affects testosterone secretion. Adult Leydig cells are responsible for testosterone production in male. The role of vitamin A in regulating the differentiation of Leydig cells is still unknown. In this study, we explored the roles and underlying mechanisms of vitamin A in Leydig cell differentiation. We found that vitamin A could regulate the Leydig cells differentiation. Leydig cell differentiation is adversely affected in mice maintained on a vitamin A-free diet. This effect is mediated by alcohol dehydrogenase 1 (ADH1). ADH1 could increase retinoic acid (RA) synthesis, then RA facilitates Leydig cell differentiation by activating the steroidogenic factor 1 gene (Nr5a1) promoter activity, which consequently promotes Leydig cell specific gene expression, resulting in progenitor Leydig cells differentiation into functional Leydig cells. This is the first study connecting a metabolic enzyme of retinol (ADH1) to the the regulation of Leydig cell differentiation, which will provide experimental evidence for the development of therapeutics to promote Leydig regeneration through the administration of a RA signaling regulator or a vitamin A supplement.
ABSTRACT
BACKGROUND: Nerve growth factor (NGF) plays essential roles in regulating the development and maintenance of central sympathetic and sensory neurons. However, the effects of NGF on hypogonadism remain unexplored. METHODS: To assess the effects of NGF on hypogonadism, we established a convenient and noninvasive way to deliver NGF to the hypothalamus by spraying liposome-encapsulated NGF into the nasal cavity. The ten-month-old aging male senescence accelerate mouse P8 (SAMP8) mice with age-related hypogonadotrophic hypogonadism were used to study the role of NGF in hypogonadism. The age-matched accelerated senescence-resistant mouse R1 (SAMR1) served as a control. The ten-month-old SAMP8 mice were treated with NGF twice per week for 12â¯weeks. Sexual hormones, sexual behaviors, and fertility were analyzed after NGF treatment. And the mechanisms of NGF in sex hormones sexual function were also studied. FINDINGS: NGF could enhance the sexual function, improve the quality of the sperm, and restore the fertility of aging male SAMP8 mice with age-related hypogonadism by activating gonadotropin-releasing hormone (GnRH) neuron and regulating secretion of GnRH. And NGF regulated the GnRH release through the PKC/p-ERK1/2/p-CREB signal pathway. INTERPRETATION: These results suggest that NGF treatment could alleviate various age-related hypogonadism symptoms in male SAMP8 and may be usefulness for age-related hypogonadotrophic hypogonadism and its related subfertility. FUND: National Natural Science Foundation of China, Natural Science Foundation of Guangdong Province, the Science and Technology Plan Project of Guangzhou, Wenzhou Science & Technology Bureau, Guangdong Province Pearl River Scholar Fund, Guangdong province science and technology innovation leading Scholar Fund.
