In the present study, we show that four unusual cholesterol precursors, 5α-cholesta-8,14-dien-3β-ol, 4-methyl-5α-cholesta-8,24-dien-3β-ol (4-methylzymosterol), 4,4,14-trimethyl-5α-cholesta-8,24-dien-3β-ol (lanosterol), and 4,4-dimethyl-5α-cholesta-8,24-dien-3β-ol (4,4-dimethylzymosterol) are present in testes of the limpet Cellana grata, which is part of one of the most primitive gastropod fami...

OBJECTIVES The present study was aimed to evaluate the time-mannered and dose-dependent effects of 5α-dihydrotestosterone (5α-DHT) on the proliferation and differentiation of bone forming cells using MC3T3-E1 cells. MATERIALS AND METHODS Cell proliferation was analyzed using MTS and phase contrast microscopic assays. Osteogenic differentiation was assessed through a series of in vitro experim...

IMPORTANCE Case reports describe persistent erectile dysfunction (PED) associated with exposure to 5α-reductase inhibitors (5α-RIs). Clinical trial reports and the manufacturers' full prescribing information (FPI) for finasteride and dutasteride state that risk of sexual adverse effects is not increased by longer duration of 5α-RI exposure and that sexual adverse effects of 5α-RIs resolve in me...

BACKGROUND The nicotinamide adenine dinucleotide phosphate-dependent membrane protein 5α-reductase catalyses the conversion of testosterone to the most potent androgen - 5α-dihydrotestosterone. Two 5α-reductase isoenzymes are expressed in humans: type I and type II. The latter is found primarily in prostate tissue. Saw palmetto extract (SPE) has been used extensively in the treatment of lower u...

Progestogens [progesterone (P(4)) and its products] play fundamental roles in the development and/or function of the central nervous system during pregnancy. We, and others, have investigated the role of pregnane neurosteroids for a plethora of functional effects beyond their pro-gestational processes. Emerging findings regarding the effects, mechanisms, and sources of neurosteroids have challe...

BACKGROUND AND PURPOSE Fluoxetine, a selective serotonin reuptake inhibitor, elevates brain concentrations of the neuroactive progesterone metabolite allopregnanolone, an effect suggested to underlie its use in the treatment of premenstrual dysphoria. One report showed fluoxetine to activate the aldo-keto reductase (AKR) component of 3α-hydroxysteroid dehydrogenase (3α-HSD), which catalyses pro...

The condition known as male pattern hair loss and benign prostatic hyperplasia are both treated with a family of drugs 5 alpha reductase (5α-reductase) inhibitors. This study shows that the flower Hibiscus rosa sinensis has 5α-reductase inhibitory action is helpful in treatment androgenic diseases. Phytochemical screening was done using petroleum ether, methanol, water extracts to identify phyt...

To explore the possibility that compounds which were identified as pheromones in experimental animals mediate human menstrual synchrony, we examined the relationship between menstrual synchrony and the ability to smell putative pheromones, 5α-androst-16-en-3α-ol (3α-androstenol) and 5α-androst-16-en-3-one (5α-androstenone). When we examined menstrual synchrony among 64 women living together in ...

The intracellular availability of glucocorticoids is regulated by the enzymes 11β-hydroxysteroid dehydrogenase 1 (HSD11B1) and 11β-hydroxysteroid dehydrogenase 2 (HSD11B2). The activity of HSD11B1 is measured in the urine based on the (tetrahydrocortisol+5α-tetrahydrocortisol)/tetrahydrocortisone ((THF+5α-THF)/THE) ratio in humans and the (tetrahydrocorticosterone+5α-tetrahydrocorticosterone)/t...

Androgens are important regulators of bone mass but the relative importance of testosterone (T) versus dihydrotestosterone (DHT) for the activation of the androgen receptor (AR) in bone is unknown. 5α-reductase is responsible for the irreversible conversion of T to the more potent AR activator DHT. There are two well established isoenzymes of 5α-reductase (type 1 and type 2), encoded by separat...