In vitro maturation (IVM) of oocytes is the procedure where the immature oocytes are cultivated in a laboratory until they are mature. Since IVM oocytes generally have low developmental competence as compared to those matured in vivo, development of an optimal IVM culture system by fine-tuning culture conditions is crucial to maintain high quality. In-depth knowledge and a deep understanding of the in vivo physiology of oocyte maturation are pre-requisites to accomplish this. Within ovarian follicles, various signaling pathways that drive oocyte development and maturation regulate interaction between oocytes and surrounding somatic cells. This review discusses the sonic hedgehog (SHH) signaling pathway, which has been demonstrated to be intimately involved in folliculogenesis and oocyte maturation. Advances in elucidating the role of the SHH signaling pathway in oocyte maturation will aid attempts to improve the current inferior in vitro oocyte maturation system.

Alopecia has emerged as one of the biggest interests in modern society. Many studies have focused on the treatment of alopecia, such as transplantation of hair follicles or inhibition of the androgen pathway. Hair growth is achieved through proper proliferation of the components such as keratinocytes and dermal papilla cells (DPCs), movement, and interaction between the two cells. The present study examined the effect of the hedgehog (Hh) signaling pathway, which is an important and fundamental signal in the cell, on the morphology and the viability of human keratinocytes and DPCs. Upregulation of Hh signaling caused a morphological change and an increase in epithelium-mesenchymal transition-related gene expression but reduced the viability of keratinocytes, while the alteration of Hh signaling did not cause any change in DPCs. The results show the possibility that the regulation of Hh signaling can be applied for the treatment of alopecia.

Hedgehog (Hh) pathway plays a key role in development from invertebrate to vertebrate. It is known to be involved in cell differentiation, polarity, proliferation, including the development of vertebrate limb and the establishment of flies’ body plan. To investigate how the regulation of Hh pathway affects the development of parthenogenetic murine embryos, the parthenogenetically activated murine embryos were treated with either cyclopamine (Cyc), an antagonist of Hh pathway, or purmorphamine, an agonist of Hh pathway. While Cyc did not affect the blastocyst formation and its total cell number, the chemical reduced the hatching rate of embryos and the expression levels of Fn1 mRNA. The results of the present study show the possibility that Cyc may affect the development of embryos at blastocyst stage by blocking Hh pathway and this may cause detrimental effect to the embryos at peri-, and post-implantation stages.

Sonic hedgehog (Shh) signaling pathway plays a key role in the development of various vertebrate embryos and remains important in adults. Although Shh signaling pathway has widely been studied in post-implantation stage embryos, only few studies are reported about pre-implantation stage embryos. To investigate the effect of Shh on pre-implantation stage embryos, cyclopamine and purmorphamine were treated to embryos in culture. Cyclopamine acts as an antagonist of the hedgehog signaling because it has a high affinity to Smoothened, a key part of the hedgehog signaling pathway. On the other hand, purmorphamine activate Smoothened and acts as a Shh signaling agonist. The oocytes were collected after superovulation and parthenogenetically activated in Chatot, Ziomek, and Bavister medium (CZB) including 10 mM strontium for 5 hr. The activated oocytes were cultured in potassium simplex optimized medium (KSOM), KSOM with 5 uM of cyclopamine, KSOM with 1 uM of purmorphamine, or KSOM with both 5 uM of cyclopamine and 1 uM of purmorphamine. After 5.5 days in culture, there was no significant difference in blastocyst development among the four experimental groups. However, the hatching rate was increased in the groups containing purmorphamine, and the blastocysts of the purmorphamine-containing groups had higher total cell number than those of other two groups when the cells were counted after Hoechst33342 staining. Quantitative real-time PCR (qRT-PCR) shows the difference of gene expression level which are related to epithelial-mesenchymal transition (EMT). Taken together, this study suggests that the increase of Shh has an effect on the increases of EMT-related genes and hatching rate of pre-implantation stage embryos, and this may improve implantation subsequently.