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Journal of the European Academy of... Feb 2022Oral finasteride is a well-established treatment for men with androgenetic alopecia (AGA), but long-term therapy is not always acceptable to patients. A topical... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Oral finasteride is a well-established treatment for men with androgenetic alopecia (AGA), but long-term therapy is not always acceptable to patients. A topical finasteride formulation has been developed to minimize systemic exposure by acting specifically on hair follicles.
OBJECTIVES
To evaluate the efficacy and safety of topical finasteride compared with placebo, and to analyse systemic exposure and overall benefit compared with oral finasteride.
METHODS
This randomized, double-blind, double dummy, parallel-group, 24-week study was conducted in adult male outpatients with AGA at 45 sites in Europe. Efficacy and safety were evaluated. Finasteride, testosterone and dihydrotestosterone (DHT) concentrations were measured.
RESULTS
Of 458 randomized patients, 323 completed the study and 446 were evaluated for safety. Change from baseline in target area hair count (TAHC) at week 24 (primary efficacy endpoint) was significantly greater with topical finasteride than placebo (adjusted mean change 20.2 vs. 6.7 hairs; P < 0.001), and numerically similar between topical and oral finasteride. Statistically significant differences favouring topical finasteride over placebo were observed for change from baseline in TAHC at week 12 and investigator-assessed change from baseline in patient hair growth/loss at week 24. Incidence and type of adverse events, and cause of discontinuation, did not differ meaningfully between topical finasteride and placebo. No serious adverse events were treatment related. As maximum plasma finasteride concentrations were >100 times lower, and reduction from baseline in mean serum DHT concentration was lower (34.5 vs. 55.6%), with topical vs. oral finasteride, there is less likelihood of systemic adverse reactions of a sexual nature related to a decrease in DHT with topical finasteride.
CONCLUSION
Topical finasteride significantly improves hair count compared to placebo and is well tolerated. Its effect is similar to that of oral finasteride, but with markedly lower systemic exposure and less impact on serum DHT concentrations.
Topics: Adult; Alopecia; Dihydrotestosterone; Double-Blind Method; Finasteride; Hair; Humans; Male
PubMed: 34634163
DOI: 10.1111/jdv.17738 -
Molecules (Basel, Switzerland) Nov 2021Benign prostatic hyperplasia (BPH) is one of the most common urinary diseases affecting men, generally after the age of 50. The prevalence of this multifactorial disease... (Review)
Review
Benign prostatic hyperplasia (BPH) is one of the most common urinary diseases affecting men, generally after the age of 50. The prevalence of this multifactorial disease increases with age. With aging, the plasma level of testosterone decreases, as well as the testosterone/estrogen ratio, resulting in increased estrogen activity, which may facilitate the hyperplasia of the prostate cells. Another theory focuses on dihydrotestosterone (DHT) and the activity of the enzyme 5α-reductase, which converts testosterone to DHT. In older men, the activity of this enzyme increases, leading to a decreased testosterone/DHT ratio. DHT may promote prostate cell growth, resulting in hyperplasia. Some medicinal plants and their compounds act by modulating this enzyme, and have the above-mentioned targets. This review focuses on herbal drugs that are most widely used in the treatment of BPH, including pumpkin seed, willow herb, tomato, maritime pine bark, Pygeum africanum bark, rye pollen, saw palmetto fruit, and nettle root, highlighting the latest results of preclinical and clinical studies, as well as safety issues. In addition, the pharmaceutical care and other therapeutic options of BPH, including pharmacotherapy and surgical options, are discussed, summarizing and comparing the advantages and disadvantages of each therapy.
Topics: 3-Oxo-5-alpha-Steroid 4-Dehydrogenase; Biological Products; Dihydrotestosterone; Estrogens; Humans; Male; Phytotherapy; Plant Extracts; Plants, Medicinal; Prostatic Hyperplasia; Serenoa; Testosterone
PubMed: 34885733
DOI: 10.3390/molecules26237141 -
Best Practice & Research. Clinical... Jul 2022Androgens are essential sex steroid hormones for both sexes. Testosterone (T) is the predominant androgen in males, while in adult females, T concentrations are about... (Review)
Review
Androgens are essential sex steroid hormones for both sexes. Testosterone (T) is the predominant androgen in males, while in adult females, T concentrations are about 15-fold lower and androgen precursors are converted to estrogens. T is produced primarily in testicular Leydig cells in men, while in women precursors are biosynthesised in the adrenal cortex and ovaries and converted into T in the periphery. The biosynthesis of T occurs via a series of enzymatic reactions in steroidogenic organs. Notably, the more potent androgen, dihydrotestosterone, may be synthesized from T in the classic pathway, however, alternate metabolic pathways also exist. The classic action of androgens on target organs is mediated through the androgen receptor, which regulates nuclear receptor gene transcription. However, the androgen-androgen receptor complex may also interact directly with membrane proteins or signaling molecules to exert more rapid effects. This review summarizes the current knowledge of androgen biosynthesis, mechanisms of action and endocrine effects in human biology, and relates these effects to respective human congenital and acquired disorders.
Topics: Androgens; Estrogens; Female; Humans; Male; Receptors, Androgen; Testis; Testosterone
PubMed: 35595638
DOI: 10.1016/j.beem.2022.101665 -
International Journal of Molecular... Jul 2020The hair cycle and hair follicle structure are highly affected by various hormones. Androgens-such as testosterone (T); dihydrotestosterone (DHT); and their prohormones,... (Review)
Review
The hair cycle and hair follicle structure are highly affected by various hormones. Androgens-such as testosterone (T); dihydrotestosterone (DHT); and their prohormones, dehydroepiandrosterone sulfate (DHEAS) and androstendione (A)-are the key factors in terminal hair growth. They act on sex-specific areas of the body, converting small, straight, fair vellus hairs into larger darker terminal hairs. They bind to intracellular androgen receptors in the dermal papilla cells of the hair follicle. The majority of hair follicles also require the intracellular enzyme 5-alpha reductase to convert testosterone into DHT. Apart from androgens, the role of other hormones is also currently being researched-e.g., estradiol can significantly alter the hair follicle growth and cycle by binding to estrogen receptors and influencing aromatase activity, which is responsible for converting androgen into estrogen (E2). Progesterone, at the level of the hair follicle, decreases the conversion of testosterone into DHT. The influence of prolactin (PRL) on hair growth has also been intensively investigated, and PRL and PRL receptors were detected in human scalp skin. Our review includes results from many analyses and provides a comprehensive up-to-date understanding of the subject of the effects of hormonal changes on the hair follicle.
Topics: Androgens; Estradiol; Female; Hair Follicle; Humans; Male; Prolactin; Sex Characteristics
PubMed: 32731328
DOI: 10.3390/ijms21155342 -
Neurobiology of Disease Jul 2020Microglia-induced neuroinflammation plays a vital role in the etiology and progression of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease...
Microglia-induced neuroinflammation plays a vital role in the etiology and progression of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease and multiple sclerosis. The neuroprotective role of androgens, including testosterone and its metabolite dihydrotestosterone (DHT), has been increasingly demonstrated in these diseases, but few studies investigated the effects of androgen on neuroinflammation. This study investigated the role of DHT in lipopolysaccharide (LPS)-induced neuroinflammation, neuronal damage and behavioral dysfunction, as well as underlying mechanisms. We showed that DHT inhibited LPS-induced release of proinflammatory factors, including TNF-α, IL-1β, IL-6; iNOS, COX-2, NO, and PGE2 in BV2 cells and primary microglia by suppressing the TLR4-mediated NF-κB and MAPK p38 signaling pathways, thus protecting SH-SY5Y neurons from inflammatory damage induced by activated microglia. In an LPS-induced neuroinflammation mouse model, endogenous DHT depletion by castration exacerbated inflammatory responses by upregulating the levels of TNF-α, IL-1β, IL-6, iNOS, and COX-2 in the serum and brain by increasing the LR4-mediated NF-κB and MAPK pathway activation, but these effects were restored by exogenous DHT supplementation. Moreover, DHT also regulated the mRNA levels of the anti-inflammatory cytokines IL-10 and IL-13 in the brain. In addition, DHT modulated the expression of Aβ, the apoptotic proteins caspase-3, Bcl-2, and Bax, and synaptophysin, as well as neuronal damage in LPS-treated mouse brains. Further behavioral tests revealed that DHT ameliorated LPS-induced spatial and learning impairment and motor incoordination, and partly improved the locomotor activity in LPS-injected mice. Therefore, this study suggests that DHT exerts anti-neuroinflammatory and neuroprotective effects; thus, androgen replacement therapy is a potential therapeutic strategy for improving cognitive and behavioral function in neuroinflammation-related diseases.
Topics: Androgens; Animals; Anti-Inflammatory Agents; Brain; Cyclooxygenase 2; Cytokines; Dihydrotestosterone; Inflammation; Lipopolysaccharides; MAP Kinase Signaling System; Mice; Microglia; NF-kappa B; Neurons; Neuroprotection; Neuroprotective Agents; Nitric Oxide Synthase Type II; Toll-Like Receptor 4; Tumor Necrosis Factor-alpha
PubMed: 32087283
DOI: 10.1016/j.nbd.2020.104814 -
Biomedicine & Pharmacotherapy =... May 2021Androgenic alopecia (AGA), also known as male pattern baldness, is one of the most common hair loss diseases worldwide. The main treatments of AGA include hair...
Androgenic alopecia (AGA), also known as male pattern baldness, is one of the most common hair loss diseases worldwide. The main treatments of AGA include hair transplant surgery, oral medicines, and LDL laser irradiation, although no treatment to date can fully cure this disease. Animal models play important roles in the exploration of potential mechanisms of disease development and in assessing novel treatments. The present study describes androgen receptor (AR) in C57BL/6 mouse hair follicles that can be activated by dihydrotestosterone (DHT) and translocate to the nucleus. This led to the design of a mouse model of androgen-induced AGA in vivo and in vitro. DHT was found to induce early hair regression, hair miniaturization, hair density loss, and changes in hair morphology in male C57BL/6 mice. These effects of DHT could be partly reversed by the AR antagonist bicalutamide. DHT had similar effects in an ex vivo model of hair loss. Evaluation of histology, organ culture, and protein expression could explain the mechanism by which DHT delayed hair regrowth.
Topics: Alopecia; Androgen Antagonists; Anilides; Animals; Dihydrotestosterone; Disease Models, Animal; Hair Follicle; Male; Mice; Mice, Inbred C57BL; Nitriles; Organ Culture Techniques; Receptors, Androgen; Signal Transduction; Tosyl Compounds
PubMed: 33517191
DOI: 10.1016/j.biopha.2021.111247 -
American Journal of Physiology.... Jul 2020Mitochondrial injury in granulosa cells is associated with the pathogenesis of polycystic ovary syndrome (PCOS). However, the protective effects of melatonin against...
Mitochondrial injury in granulosa cells is associated with the pathogenesis of polycystic ovary syndrome (PCOS). However, the protective effects of melatonin against mitochondrial injury in the granulosa cells of PCOS remain unclear. In this study, decreased mitochondrial membrane potential and mtDNA content, increased number of autophagosomes were found in the granulosa cells of PCOS patients and the dihydrotestosterone (DHT)-treated KGN cells, with decreased protein level of the autophagy substrate p62 and increased levels of the cellular autophagy markers Beclin 1 and LC3B-II, while the protein levels of PTEN-induced kinase-1 (PINK1) and Parkin were increased and the level of sirtuin 1 (SIRT1) was decreased. DHT-induced PCOS-like mice also showed enhanced mitophagy and decreased mRNA expression. Melatonin treatment significantly increased the protein level of SIRT1 and decreased the levels of PINK1/Parkin, whereas it ameliorated the mitochondrial dysfunction and PCOS phenotype in vitro and in vivo. However, when the KGN cells were treated with siRNA to knock down SIRT1 expression, melatonin treatment failed to repress the excessive mitophagy. In conclusion, melatonin protects against mitochondrial injury in granulosa cells of PCOS by enhancing SIRT1 expression to inhibit excessive PINK1/Parkin-mediated mitophagy.
Topics: Adult; Animals; Antioxidants; Autophagosomes; Autophagy; Beclin-1; Case-Control Studies; Cell Line; DNA, Mitochondrial; Dihydrotestosterone; Female; Granulosa Cells; Humans; Melatonin; Membrane Potential, Mitochondrial; Mice; Microtubule-Associated Proteins; Mitophagy; Polycystic Ovary Syndrome; Protein Kinases; Sirtuin 1; Ubiquitin-Protein Ligases
PubMed: 32343612
DOI: 10.1152/ajpendo.00006.2020 -
The World Journal of Men's Health Jul 20205α-dihydrotestosterone (5α-DHT) is the most potent natural androgen. 5α-DHT elicits a multitude of physiological actions, in a host of tissues, including prostate,... (Review)
Review
5α-dihydrotestosterone (5α-DHT) is the most potent natural androgen. 5α-DHT elicits a multitude of physiological actions, in a host of tissues, including prostate, seminal vesicles, hair follicles, skin, kidney, and lacrimal and meibomian glands. However, the physiological role of 5α-DHT in human physiology, remains questionable and, at best, poorly appreciated. Recent emerging literature supports a role for 5α-DHT in the physiological function of liver, pancreatic β-cell function and survival, ocular function and prevention of dry eye disease and kidney physiological function. Thus, inhibition of 5α-reductases with finasteride or dutasteride to reduce 5α-DHT biosynthesis in the course of treatment of benign prostatic hyperplasia (BPH) or male pattern hair loss, known as androgenetic alopecia (AGA) my induces a novel form of tissue specific androgen deficiency and contributes to a host of pathophysiological conditions, that are yet to be fully recognized. Here, we advance the concept that blockade of 5α-reductases by finasteride or dutasteride in a mechanism-based, irreversible, inhabitation of 5α-DHT biosynthesis results in a novel state of androgen deficiency, independent of circulating testosterone levels. Finasteride and dutasteride are frequently prescribed for long-term treatment of lower urinary tract symptoms in men with BPH and in men with AGA. This treatment may result in development of non-alcoholic fatty liver diseases (NAFLD), insulin resistance (IR), type 2 diabetes (T2DM), dry eye disease, potential kidney dysfunction, among other metabolic dysfunctions. We suggest that long-term use of finasteride and dutasteride may be associated with health risks including NAFLD, IR, T2DM, dry eye disease and potential kidney disease.
PubMed: 32202088
DOI: 10.5534/wjmh.200012