title: Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice.
abstract: Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo.
authors.affiliation: Department of Infertility and Sexual Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Zhi-Jun
authors.initials: ZJ
authors.lastname: Zang
authors.affiliation: Department of Dermatology, Shunde First People's Hospital Affiliated to Southern Medical University, Foshan, China.
authors.forename: Hong-Feng
authors.initials: HF
authors.lastname: Tang
authors.affiliation: Department of Histopathology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Tuo
authors.affiliation: Center for Reproductive Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Wei-Jie
authors.initials: WJ
authors.lastname: Xing
authors.affiliation: Department of Dermatology, Guangdong Provincial Dermatology Hospital, Guangzhou, China.
authors.forename: Su-Yun
authors.initials: SY
authors.lastname: Ji
authors.affiliation: Reproductive Medicine Centre and Guangdong Provincial Key Laboratory of Reproductive Medicine, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Gao
authors.affiliation: Department of Urology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.
authors.forename: Chun-Hua
authors.initials: CH
authors.lastname: Deng
mesh_terms: D000375:Aging / Q000097:blood / Q000187:drug effects*; D000818:Animals; D000999:Antlers; D001835:Body Weight / Q000187:drug effects; D003670:Deer; D008297:Male; D008516:Medicine, Chinese Traditional; D051379:Mice; D008810:Mice, Inbred C57BL; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D013739:Testosterone / Q000097:blood*; D014020:Tissue Extracts / Q000494:pharmacology*
chemical_list: D014020:Tissue Extracts; D013739:Testosterone