Anti-SRD5A1 monoclonal antibody Made to order

Aconitine might have reproductive toxicity and the effects of aconitine on androgen synthesis in Leydig cells remain unclear. Here, we explore how aconitine affects androgen synthesis and metabolism in rat immature Leydig cells in vitro. Immature Leydig cells were isolated from 35-day-old male Sprague Dawley rats and cultured with 0-50 mu M aconitine for 3 h in combination with LH, 8Br-cAMP, 22R-hydroxycholesterol, pregnenolone, progesterone, androstenedione, testosterone, and dihydrotestosterone, respectively. Medium androgens were measured. The levels of Leydig cell mRNAs, Lhcgr, Scarb1, Star, Cyp11a1, Hsd3b1, Cyp17a1, Hsd17b3, Srd5a1, and Akr1c14, were measured by qPCR. ROS and apoptosis were determined after 24-h aconitine treatment. Aconitine inhibited basal androgen production in Leydig cells at 0.05 mu M and the higher concentrations. Aconitine blocked pregnenolone, progesterone, and androstenedione mediated androgen outputs without affecting 22R-hydroxycholesterol-mediated androgen production at 5 mu M. Aconitine also inhibited LH and 8Br-cAMP stimulated androgen outputs at 5 mu M. Further investigation showed that aconitine blocked androgen synthesis via down-regulating the expression of Scarbl, Hsd3b1, Cypl7al, and Hsdl7b3. M 50 mu M, aconitine also induced ROS generation and increased apoptotic rate of Leydig cells. Aconitine lowered serum testosterone levels at 1.5 mg/kg after 7 days of oral exposure from postnatal day 35. In conclusion, aconitine inhibits androgen synthesis.

Purpose: Polymorphisms in the genes SRD5A1 and SRD5A2 encoding androgen biosynthetic 5 alpha-reductase enzymes have been associated with an altered risk of biochemical recurrence after radical prostatectomy in localized prostate cancer. Experimental Design: To gain potential insights into SRD5A biologic effects, we examined the relationship between SRD5A prognostic markers and endogenous sex-steroid levels measured by mass spectrometry in plasma samples and corresponding prostatic tissues of patients with prostate cancer. Results: We report that five of the seven SRD5A markers differentially affect sex-steroid profiles of dihydrotestosterone and its metabolites in both the circulation and prostatic tissues of patients with prostate cancer. Remarkably, a 32% increase in intraprostatic testosterone levels was observed in the presence of the high-risk SRD5A rs2208532 polymorphism. Moreover, SRD5A2 markers were associated predominantly with circulating levels of inactive glucuronides. Indeed, the rs12470143 SRD5A2 protective allele was associated with high circulating androstane-3 alpha, 17 beta-diol-17-glucuronide (3 alpha-diol-17G) levels as opposed to lower levels of both 3 alpha-diol-17G and androsterone-glucuronide observed with the rs2208532 SRD5A2 risk allele. Moreover, SRD5A2 rs676033 and rs523349 (V89L) risk variants, in strong linkage disequilibrium, were associated with higher circulating levels of 3 alpha-diol-3G. The SRD5A2 rs676033 variant further correlated with enhanced intraprostatic exposure to 5 alpha-reduced steroids (dihydrotestosterone and its metabolite 3 beta-diol). Similarly, the SRD5A1 rs166050C risk variant was associated with greater prostatic exposure to androsterone, whereas no association was noted with circulating steroids. Conclusions: Our data support the association of 5 alpha-reductase germline polymorphisms with the hormonal milieu in patients with prostate cancer. Further studies are needed to evaluate if these variants influence 5 alpha-reductase inhibitor efficacy. (C) 2013 AACR.