Inhibitory activities of Puerariae Flos against testosterone 5α-reductase and its hair growth promotion activities

Oriental traditional herbal Medicine--Puerariae Flos: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Pueraria Flos (PF), a traditional herbal medicine, is botanically from the dried flowers of Pueraria lobate (Willd.) Ohwi. (Chinese: ) or Pueraria thomsonii Benth. (Chinese: ). It has a long history of thousands of years in China for awakening the spleen, clearing the lungs, relieving alcohol.

AIM OF THE REVIEW

This review aims to report the up-to-date research progress in ethnopharmacology, phytochemistry, pharmacology and toxicology, metabolism and therapeutic application of PF, so as to provide a strong basis for future clinical treatment and scientific research.

MATERIALS AND METHODS

Relevant information on PF was collected from scientific literature databases including PubMed, CNKI and other literature sources (Ph.D. and M.Sc. dissertations and Chinese herbal classic books) by using the keyword "Puerariae".

RESULTS

Briefly, phytochemical research report has isolated 39 flavonoids, 19 saponins and 25 volatile oils from PF. Flavonoids and saponins are the most important bioactive compounds, and most of the quality control studies focus on these two types of compounds. Modern pharmacological studies have revealed their significant biological activities in relieving alcoholism, hepatoprotective, anti-tumor, anti-inflammatory, and anti-oxidation, which provides theoretical support for the traditional use.

CONCLUSIONS

Comprehensive analysis showed that pharmacological activity of most purified compounds from PF had not been reported. Kakkalide, tectoridin and their deglycosylated metabolites (irisolidone and tectorigenin) has been focused on excessively due to their higher content and better activities. This leads to low development and resources waste. Interestingly, PF made a breakthrough in the field of food. Many kinds of fat-lowering foods such as PILLBOX Onaka have been popular in Japan market, which received extensive attention. Therefore, we suggest that future research can be paid attention on the development of the plant's function in the field of food and medicine, as well as the transformation from experimental to clinical.

Caffeic acid N-[3,5-bis(trifluoromethyl)phenyl] amide as a non-steroidal inhibitor for steroid 5α-reductase type 1 using a human keratinocyte cell-based assay and molecular dynamics

Caffeic acid derivatives containing amide moieties similar to those of finasteride and dutasteride were synthesized. An in vitro inhibitory activity evaluation of caffeic acid (1) and its amide derivatives (2 - 4) against the steroid 5α-reductase type 1 (SRD5A1) produced by human keratinocyte cells coupled with the non-radioactive high-performance thin-layer chromatography detection revealed that caffeic acid N-[3,5-bis(trifluoromethyl)phenyl] amide (4) was a promising non-steroidal suppressor, with a half-maximal inhibitory concentration (IC₅₀) of 1.44 ± 0.13 µM and relatively low cytotoxicity with an IC₅₀ of 29.99 ± 8.69 µM. The regulatory role of compound 4 against SRD5A1 involved both suppression of SRD5A1 expression and mixed mode SRD5A1 inhibition. The K_i value of compound 4 was 2.382 µM based on the whole-cell kinetic studies under specific conditions. Molecular docking and molecular dynamics simulations with AlphaFold generated the human SRD5A1 structure and confirmed the stability of compound 4 at the SRD5A1 catalytic site with greater interactions, including hydrogen bonding of the key M119 amino-acid residue than those of finasteride and dutasteride. Thus, compound 4 shows the potential for further development as an SRD5A1 suppressor for androgenic alopecia treatment.

Modulation of Hair Growth Promoting Effect by Natural Products

A large number of people suffer from alopecia or hair loss worldwide. Drug-based therapies using minoxidil and finasteride for the treatment of alopecia are available, but they have shown various side effects in patients. Thus, the use of new therapeutic approaches using bioactive products to reduce the risk of anti-hair-loss medications has been emphasized. Natural products have been used since ancient times and have been proven safe, with few side effects. Several studies have demonstrated the use of plants and their extracts to promote hair growth. Moreover, commercial products based on these natural ingredients have been developed for the treatment of alopecia. Several clinical, animal, and cell-based studies have been conducted to determine the anti-alopecia effects of plant-derived biochemicals. This review is a collective study of phytochemicals with anti-alopecia effects, focusing mainly on the mechanisms underlying their hair-growth-promoting effects.

Qualitative and quantitative evaluation of Flos Puerariae by using chemical fingerprint in combination with chemometrics method

In order to better control the quality of Flos Puerariae (FP), qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study. First, the fingerprint of FP was developed by HPLC and the chemical markers were screened out by similarity analysis (SA), hierarchical clustering analysis (HCA), principal components analysis (PCA), and orthogonal partial least squares discriminant analysis (OPLS-DA). Next, the chemical constituents in FP were profiled and identified by HPLC coupled to Fourier transform ion cyclotron resonance mass spectrometry (HPLC-FT-ICR MS). Then, the characteristic constituents in FP were quantitatively analyzed by HPLC. As a result, 31 common peaks were assigned in the fingerprint and 6 of them were considered as qualitative markers. A total of 35 chemical constituents were detected by HPLC-FT-ICR MS and 16 of them were unambiguously identified by comparing retention time, UV absorption wavelength, accurate mass, and MS/MS data with those of reference standards. Subsequently, the contents of glycitin, genistin, tectoridin, glycitein, genistein, and tectorigenin in 13 batches of FP were detected, ranging from 0.4438 to 11.06 mg/g, 0.955 to 1.726 mg/g, 9.81 to 57.22 mg/g, 3.349 to 41.60 mg/g, 0.3576 to 0.989 mg/g, and 2.126 to 9.99 mg/g, respectively. In conclusion, fingerprint analysis in combination with chemometrics methods could discover chemical markers for improving the quality control standard of FP. It is expected that the strategy applied in this study will be valuable for further quality control of other traditional Chinese medicines.

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The qualitative and quantitative analysis were carried out for Flos Puerariae.

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Fingerprints were combined with different chemometrics to discover the qualitative markers FP.

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Thirty five constituents of FP were characterized by HPLC-FT-ICR MS.

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Six chemical constituents were simultaneously determined by HPLC.

An appraisal of laboratory models of androgenetic alopecia: A systematic review

Background

Androgenetic alopecia (AGA) is the most common form of non‐scarring alopecia in humans. Several studies have used different laboratory models to study the pathogenesis and interventions for AGA. These study models have proved beneficial and have led to the approval of two drugs. However, the need to build on existing knowledge remains by examining the relevance of study models to the disease.

Objective

We sought to appraise laboratory or pre‐clinical models of AGA.

Method

We searched through databases (PubMed, ScienceDirect, Web of Science, World CAT, Scopus and Google Scholar) for articles on AGA‐related studies from 1942 to March 2019 with a focus on study models.

Results

The search rendered 101 studies after screening and deduplication. Several studies (70) used in vitro models, mostly consisting of two‐dimensional monolayer cells for experiments involving the characterization of androgen and 5‐alpha reductase (5AR) and inhibition thereof, the effects of dihydrotestosterone (DHT) and biomarker(s) of AGA. Twenty‐seven studies used in vivo models of mice and monkeys to investigate DHT synthesis, the expression and inhibition of 5AR and hair growth. Only four studies used AGA‐related or healthy excisional/punch biopsy explants as ex vivo models to study the action of 5AR inhibitors and AGA‐associated genes. No study used three‐dimensional [3‐D] organoids or organotypic human skin culture models.

Conclusion

We recommend clinically relevant laboratory models like human or patient‐derived 3‐D organoids or organotypic skin in AGA‐related studies. These models are closer to human scalp tissue and minimize the use of laboratory animals and could ultimately facilitate novel therapeutics.

Physcion, a novel inhibitor of 5α-reductase that promotes hair growth in vitro and in vivo

Androgenic alopecia (AGA) has a high incidence. Excess dihydrotestosterone in blood capillaries, which is converted from testosterone by 5α-reductase, is an AGA causative factor. We identified the inhibitory activity of four Polygonum multiflorum compounds against 5α-reductase via high-performance liquid chromatography, and the results showed that Physcion was a potent 5α-reductase inhibitor. Additionally, we found that through inhibiting 5α-reductase expression, Physcion could shorten the time of dorsal skin darkening and hair growth, improve hair follicle morphology, and significantly increase hair follicle count. Eventually, through molecular docking study, we found the binding energy and molecular interactions between Physcion and 5α-reductase type II. These results suggested that Physcion is a potent 5α-reductase inhibitor, as well as a new natural medicine for treating AGA.

An in vivo explorative study to observe the protective effects of Puerariae flos extract on chronic ethanol exposure and withdrawal male mice

Protective effects of Puerariae flos extract (PFE) on ethanol (EtOH) exposure have been previously verified. This study attempts to explore the protective effects of PEF on EtOH withdrawal models. Sixty male Kunming mice were involved which were randomly divided into five groups (intact control, EtOH group (35-day EtOH exposure), EtOH withdrawal group (28-day exposure + 7-day withdrawal), EtOH withdrawal group + positive control (Deanxit) group, and EtOH withdrawal group + PFE group). The changes of neuropsychological behaviors; hippocampal BDNF expression and CA1 neuronal density; and plasma corticotropin-releasing hormone (CRH), ACTH, and CORT levels were observed. It was found that depression-like behaviors reduced by EtOH exposure and increased by withdrawal under the 28-day EtOH exposure and 7-day withdrawal conditions. In addition, anxiety-like behaviors worsened by EtOH exposure and unchanged by withdrawal. Deanxit and PEF ameliorated such behaviors (vs. withdrawal group). Hippocampal BDNF expression was significantly downregulated by EtOH exposure and upregulated by withdrawal. Deanxit and PEF significantly upregulated the BDNF expression. The hippocampal CA1 neuronal density significantly decreased by EtOH exposure but unchanged by withdrawal and treatments. The plasma CRH, ACTH, and CORT levels show a significant enhancement by EtOH exposure and reduced by withdrawal. They were further reduced by Deanxit and PEF. The protective effects of PEF on EtOH chronic withdrawal mouse models were verified. The results of this study also indicated a complicated scenario of neuropsychological behaviors, hippocampal BDNF expression, and hypothalamic-pituitary-adrenal axis which are affected by the timing of EtOH exposure and withdrawal.

A comprehensive review of biochemical factors in herbs and their constituent compounds in experimental studies on alopecia

ETHNOPHARMACOLOGICAL RELEVANCE

Alopecia is a chronic condition that may cause emotional and psychological distress to patients, which may significantly impact a patient's quality of life. As conventional treatments have only a transient therapeutic effect and result in unwanted side effects, many patients have attempted to find therapeutic herbs or compounds that function as safer and more potent treatments for alopecia. Many such herbs have been used in complementary and alternative medicine (CAM) for centuries; however, there is a lack of information on the therapeutic mechanisms of herbs used for the treatment of alopecia.

AIM OF THE STUDY

The aim of this review was to perform a critical assessment of the methods and results of experimental studies related to alopecia and to provide the potential mechanisms of action of herbs and their constituent compounds used in the identified studies, in particular, in relation to the stages of the cell cycle. We hope to better guide the clinical application and scientific research of herbs for the treatment of alopecia.

MATERIALS AND METHODS

We reviewed experimental studies to determine the methods used and the mechanism of action of the herbs and constituent compounds. Databases, including Medline (via PubMed), EMBASE, OASIS, and RISS, were searched for the following keywords: "medicinal plants," "alopecia," "alopecia areata," "androgenetic alopecia," "animal experiment," and "in vitro study." We also assessed the risks of bias, toxicity, and taxonomy to determine the quality of information.

RESULTS

C57BL/6 mice and human dermal papilla cells were the most commonly used models for in vivo and in vitro studies, respectively. Many herbs and their constituent compounds were used to treat alopecia by managing the hair cycle, keratinocyte proliferation, apoptosis, angiogenesis, hormones, and inflammation. These compounds prolong the anagen phase, shorten the transition from the telogen to phase anagen, and inhibit premature catagen phase.

CONCLUSIONS

This review has further elucidated the therapeutic mechanisms of herbs and their constituent compounds that are relevant to alopecia and discussed the effectiveness of using herbal treatments. There is a need to develop evidence regarding the quality control, taxonomy, and toxicology of these compounds. Such improvements will provide a better quality of evidence to ensure the efficacy and safety of herbs and compounds used for the treatment of alopecia.

Discovery of Natural Steroid 5 Alpha-Reductase Inhibitors

Human steroid 5 alpha-reductases (S5αRs) and NADPH irreversibly reduce testosterone to the more potent dihydrotestosterone (DHT). S5αR inhibitors are useful treatments for DHT-dependent diseases, including benign prostatic hyperplasia, androgenic alopecia and hair growth, and acne. There are three S5αR isozymes, and there is a need for safer and more isozyme selective inhibitors than finasteride and dutasteride currently licensed. In this study, we review the methods used to screen for S5αR inhibitory activity and describe studies that characterize the ability of herbal preparations and their constituents to inhibit S5αRs. We identified enormous variations between studies in IC₅₀s for finasteride and dutasteride used as standards. Accordingly, we make several recommendations: Stable isozyme specific transfection systems need creating a standardized enzyme/microsome preparation and all three isozymes, as well as androgen receptor binding, should be tested; agreed reaction conditions, especially the substrate concentrations, and separation/quantitation method optimized for high throughput screening; systematic screening of herbal compounds and most extensive use of leads to develop more potent and isozyme specific inhibitors.

The new paradigm for androgenetic alopecia and plant-based folk remedies: 5α-reductase inhibition, reversal of secondary microinflammation and improving insulin resistance

ETHNOPHARMACOLOGICAL RELEVANCE

Research in the past half a century has gradually sketched the biological mechanism leading to androgenetic alopecia (AGA). Until recently the aetiological paradigm has been too limited to enable intelligent commentary on the use of folk remedies to treat or reduce the expression of this condition. However, our understanding is now at a point where we can describe how some folk remedies work, predict how effective they will be or why they fail.

RESULTS

The new paradigm of AGA is that inheritance and androgens (dihydrotestosterone) are the primary contributors and a secondary pathology, microinflammation, reinforces the process at more advanced stages of follicular miniaturisation. The main protagonist to microinflammation is believed to be microbial or Demodex over-colonisation of the infundibulum of the pilosebaceous unit, which can be ameliorated by antimicrobial/acaricidal or anti-inflammatory therapies that are used as adjuvants to androgen dependent treatments (either synthetic or natural). Furthermore, studies reveal that suboptimal androgen metabolism occurs in both AGA and insulin resistance (low SHBG or high DHT), suggesting comorbidity. Both can be ameliorated by dietary phytochemicals, such as specific classes of phenols (isoflavones, phenolic methoxy abietanes, hydroxylated anthraquinones) or polycyclic triterpenes (sterols, lupanes), by dual inhibition of key enzymes in AGA (5α-reductase) and insulin resistance (ie., DPP-4 or PTP1B) or agonism of nuclear receptors (PPARγ). Evidence strongly indicates that some plant-based folk remedies can ameliorate both primary and secondary aetiological factors in AGA and improve insulin resistance, or act merely as successful adjuvants to mainstream androgen dependent therapies.

CONCLUSION

Thus, if AGA is viewed as an outcome of primary and secondary factors, then it is better that a 'multimodal' or 'umbrella' approach, to achieve cessation and/or reversal, is put into practice, using complementation of chemical species (isoflavones, anthraquinones, procyanidins, triterpenes, saponins and hydrogen sulphide prodrugs), thereby targeting multiple 'factors'.

Screening of Euphorbiaceae Plant Extracts for Anti-5α-reductase

In our research program to find novel agents for alopecia from natural plant resources, we screened Euphorbiaceae plant extracts using an anti-5α-reductase assay. Among the samples tested, the extract of Phyllanthus urinaria showed the most potent activity with 24.3 and 64.6% inhibition at 50 and 200 µg/mL against the enzyme, respectively. The extract also suppressed the androgen activity of dihydrotestosterone in LNCaP cell line. These results show that the extract of P. urinaria may be a multi-potent agent for androgen-derived alopecia. We tested for activity on a hair regrowth model using mice. The extract of P. urinaria showed hair regrowth activity at 5 mg/mouse/d administration. Furthermore, the active principle for anti-5α-reductase activity was determined as stigmasterol glucoside from activity-guided fractionation and the IC₅₀ was 27.2 µM. These results suggest that extract of P. urinaria may be a promising candidate anti-alopecia agent.

The promotion of hair regrowth by topical application of a Perilla frutescens extract through increased cell viability and antagonism of testosterone and dihydrotestosterone

This study investigated the potential hair regrowth effects associated with a plant extract of Perilla frutescens, which was selected due to its putative hair regrowth activity. Extracts were prepared from dried P. frutescens suspended in distilled water, where the resultant aqueous suspension was fractionated sequentially using hexane, ethyl acetate, n-butanol, and distilled water. We observed that the n-butanol fraction resulted in the highest hair regrowth activity. The n-butanol soluble fraction of P. frutescens extract (BFPE) was further separated using AB-8 macroporous resin and silica gel chromatography to obtain rosmarinic acid (RA), which demonstrated effective hair growth regeneration potential. BFPE also showed in vivo anti-androgenic activity following the use of a hair growth assay in testosterone-sensitive male C57Bl/6NCrSlc mice. Furthermore, the effects of cell viability promotion were investigated following an in vitro analysis in primary hair follicle fibroblast cells (PHFCs) treated with RA. The results suggested that RA was the active compound in P. frutescens that triggers hair growth, and RA could be a potential therapeutic agent for the promotion of hair growth and prevention of androgenetic alopecia (AGA).

Icariin promotes mouse hair follicle growth by increasing insulin-like growth factor 1 expression in dermal papillary cells

BACKGROUND

Icariin is a major flavonoid isolated from Epimedium spp. leaves (Epimedium Herba), and has multiple pharmacological functions, including anti-angiogenesis, anti-oxidant, anti-inflammatory and immunoprotective effects.

AIM

To investigate whether icariin can stimulate growth of hair follicles in mice and the underlying mechanism.

METHODS

In vitro, the effect of icariin on hair growth was assessed by using a vibrissae hair follicle (VHF) organ-culture model. The proliferation of hair matrix keratinocytes and the expression of insulin-like growth factor (IGF)-1 in follicles were examined by double immunostaining for 5-bromo-2'-deoxyuridine and IGF-1, in the presence or absence of icariin. Dermal papilla cells (DPCs) were cultured and IGF-1 level was measured by reverse transcription-PCR and ELISA after icariin treatment. In vivo, the effect of icariin on hair growth was examined by gavage feeding of icariin to mice whose backs had been depilated, and the conversion of telogen to anagen hair was observed.

RESULTS

Treatment with icariin promoted hair shaft elongation, prolonged the hair cycle growth phase (anagen) in cultured VHFs, and accelerated transition of hair cycle from telogen to anagen phase in the dorsal skin of mice. There was significant proliferation of matrix keratinocytes and an increased level of IGF-1 in cultured VHFs. Moreover, icariin treatment upregulated IGF-1 mRNA expression in DPCs and increased IGF-1 protein content in the conditioned medium of DPCs.

CONCLUSIONS

These results suggest that icariin can promote mouse hair follicle growth via stimulation of IGF-1 expression in DPCs.

Identification of a new plant extract for androgenic alopecia treatment using a non-radioactive human hair dermal papilla cell-based assay

BACKGROUND

Androgenic alopecia (AGA) is a major type of human scalp hair loss, which is caused by two androgens: testosterone (T) and 5α-dihydrotestosterone (5α-DHT). Both androgens bind to the androgen receptor (AR) and induce androgen-sensitive genes within the human hair dermal papilla cells (HHDPCs), but 5α-DHT exhibits much higher binding affinity and potency than T does in inducing the involved androgen-sensitive genes. Changes in the induction of androgen-sensitive genes during AGA are caused by the over-production of 5α-DHT by the 5α-reductase (5α-R) enzyme; therefore, one possible method to treat AGA is to inhibit this enzymatic reaction.

METHODS

RT-PCR was used to identify the presence of the 5α-R and AR within HHDPCs. A newly developed AGA-relevant HHDPC-based assay combined with non-radioactive thin layer chromatography (TLC) detection was used for screening crude plant extracts for the identification of new 5α-R inhibitors.

RESULTS

HHDPCs expressed both 5α-R type 1 isoform of the enzyme (5α-R1) and AR in all of the passages used in this study. Among the thirty tested extracts, Avicennia marina (AM) displayed the highest inhibitory activity at the final concentration of 10 μg/ml, as the production of 5α-DHT decreased by 52% (IC50 = 9.21 ± 0.38 μg/ml).

CONCLUSIONS

Avicennia marina (AM) was identified as a potential candidate for the treatment of AGA based on its 5α-R1-inhibitory activity.

Inhibitory activities of some traditional Chinese herbs against testosterone 5α-reductase and effects of Cacumen platycladi on hair re-growth in testosterone-treated mice

ETHNOPHARMACOLOGICAL RELEVANCE

Many traditional Chinese medicines (TCM) have been used for hundreds of years for hair blackening and hair nourishing, and now many of them are commonly used in Chinese herbal shampoo to nourish the hair and promote hair growth.

AIMS OF THE STUDY

The present study was performed to screen 5α-reductase (5αR) inhibitors from traditional Chinese medicines, evaluate its hair growth promoting activity in vivo, and further investigate its effects on androgen metabolism and the expression of 5αR II in hair follicles.

MATERIALS AND METHODS

Nine TCM which were dried, ground and extracted by maceration with 75% ethanol or distilled water were used for screening 5αR inhibitors, and enzymes were extracted from the rat epididymis. The leaves of Platycladus orientalis (L.) Franco was used to evaluate the in vivo anti-androgenic activity. Skin color was observed daily and the hair re-growth was assessed by assigning the hair growth score. The longitudinal sections of hair follicles were used for observing follicle morphology, classifying of distinct stages of hair follicle morphogenesis and calculate the average score. The transverse sections were used for determination of hair follicle counts. Testosterone (T), Dihydrotestosterone (DHT) and Estradiol (E2) levels in serum and skin tissue were detected by ELISA kits. The immunofluorescence assay was used to detect the influence of CP-ext on 5αR expression in dorsal skin.

RESULTS

We found the extract of Ganoderma lucidum (GL-ext), Polygonum multiflori (PM-ext), Cacumen platycladi (CP-ext) and Cynomorium songaricum (CS-ext) showed stronger 5αR inhibitory activity. CP-ext (5mg and 2mg/mouse/day) could significantly shorten the time of the dorsal skin darkening and got longhaired (P<0.01), and showed high hair re-growth promoting activity. Furthermore the histological data of hair follicles in each group showed that CP-ext could promote the growth of hair follicle and slowed down hair follicles enter the telogen. What's more CP-ext significantly reduced DHT levels and down-regulated the expression of 5αRⅡin skin (P<0.01).

CONCLUSIONS

GL-ext, PM-ext, CP-ext and CS-ext showed strong 5αR inhibitory activity. CP-ext possesses high hair growth promoting activity in the in vivo androgen-sensitive mouse model via inhibiting the 5αR activity, decreasing the DHT levels and in turn suppressing the expression of 5αR. Our study may contribute to the development of a new generation of herbal supplements with clearer material basis of pharmacodynamic for treating androgenic alopecia (AGA).

Potential targets in the discovery of new hair growth promoters for androgenic alopecia

INTRODUCTION

Androgenic alopecia (AGA) is the major type of scalp hair loss affecting 60 - 70% of the population worldwide. It is caused by two potent androgens, namely testosterone (T) and 5α-dihydrotestosterone (5α-DHT). Till date, only two FDA-approved synthetic drugs, minoxidil and finasteride, are used to cure AGA with only 35 and 48% success, respectively; therefore, a search for new drug based on the mechanism of androgens action is still needed.

AREAS COVERED

Relevant literature was reviewed to identify current therapeutic targets and treatments for AGA. The potential targets are classified into three categories: i) 5α-reductase; ii) androgen receptor and iii) growth-factor-producing genes related to hair growth.

EXPERT OPINION

Relevant assay systems using the right targets are required in order to obtain specific and effective drugs for AGA treatment. It is unlikely that single targeted agents will be sufficient for treating AGA, and therefore, it would be a challenge to obtain compounds with multiple activities.

Avicequinone C isolated from Avicennia marina exhibits 5α-reductase-type 1 inhibitory activity using an androgenic alopecia relevant cell-based assay system

Avicennia marina (AM) exhibits various biological activities and has been traditionally used in Egypt to cure skin diseases. In this study, the methanolic heartwood extract of AM was evaluated for inhibitory activity against 5α-reductase (5α-R) [E.C.1.3.99.5], the enzyme responsible for the over-production of 5α-dihydrotestosterone (5α-DHT) causing androgenic alopecia (AGA). An AGA-relevant cell-based assay was developed using human hair dermal papilla cells (HHDPCs), the main regulator of hair growth and the only cells within the hair follicle that are the direct site of 5α-DHT action, combined with a non-radioactive thin layer chromatography (TLC) detection technique. The results revealed that AM is a potent 5α-R type 1 (5α-R1) inhibitor, reducing the 5α-DHT production by 52% at the final concentration of 10 µg/mL. Activity-guided fractionation has led to the identification of avicequinone C, a furanonaphthaquinone, as a 5α-R1 inhibitor with an IC50 of 9.94 ± 0.33 µg/mL or 38.8 ± 1.29 µM. This paper is the first to report anti-androgenic activity through 5α-R1 inhibition of AM and avicequinone C.

Suppression of benign prostate hyperplasia by Kaempferia parviflora rhizome

Background:

Kaempferia parviflora rhizome is used as a folk medicine in Thailand for the treatment of various symptoms. In the present study, the inhibitory activities of extract from K. parviflora rhizome against 5α-reductase (5αR) were subjected. Furthermore, the effects of the extract from K. parviflorar hizome in benign prostate hyperplasia (BPH) were studied using the model mice.

Materials and Methods:

Preparations of extracts from the rhizomes of K. parviflora, Curcuma zedoaria and Zingiber officinale, and methoxyflavones isolated from K. parviflora was used for 5αR inhibition assay. The effects of K. parviflora extract on growth suppression for the prostates and seminal vesicles were performed based on the Hershberger's method. The K. parviflora extract was administered to castrated mice for 14 days.

Results:

K. parviflora extract showed more potent inhibitory activity on 5αR than C. zedoaria and Z. officinale extracts. The active principles were identified as 3,5,7,3’,4’-pentamethoxyflavone and 5,7,3’,4’-tetramethoxyflavone by activity guided fractionation. Furthermore, K. parviflora extract suppressed the weights of prostates and seminal vesicles in BPH model rats by daily administration for 14 days.

Conclusion:

These results indicate that K. parviflora extract can be a promising agent for the treatment of BPH.