Polygonum multiflorum Radix extract protects human foreskin melanocytes from oxidative stress in vitro and potentiates hair follicle pigmentation ex vivo

Gynostemma pentaphyllum Makino extract induces hair growth and exhibits an anti-graying effect via multiple mechanisms

BACKGROUND

In traditional Asian medicine, Gynostemma pentaphyllum Makino leaf extract (Gp) is used to treat aging, metabolic syndrome, diabetes, and neurodegenerative diseases. Hair loss and hair-graying are common phenomena that haunt everyone. However, whether Gp activities on inhibition of hair loss and getting gray have been rarely studied.

AIM

Study the Gp activity and mechanism by in vivo and in vitro experiments to explore its application on hair health.

METHODS

In the present study, we determined the effects of Gp on the expression of hair growth-related genes and proliferation of human dermal papilla cells (hDPCs). Furthermore, Gp was topically applied to the hair-shaved skin of male C57BL/6 mice, and the histological profile of the skin was studied. Because emotional stress may lead to melanocyte disappearance, norepinephrine-exposed mice B16 melanocytes were treated with Gp to elucidate the anti-hair graying capacity of Gp in response to this stress type.

RESULTS

Gp stimulated the proliferation of hDPCs and the Wnt signaling pathways associated with hair growth; furthermore, the expression of the hair loss-related gene transforming growth factor-β1 was suppressed. Gp treatment significantly increased the size of hair follicles in the treated mice and stimulated them. Moreover, Gp not only increased melanin synthesis but also tyrosinase activity in B16 cells. Quantitative real-time polymerase chain reaction revealed that Gp increased melanin synthesis by increasing the expression of tyrosine-related protein-1, tyrosine-related protein-2, tyrosinase, and microphthalmia-associated transcription factor.

CONCLUSION

Our study provides preclinical evidence regarding the potential of Gp as a promising hair growth and anti-graying agent.

A comprehensive review of traditional uses, phytochemistry and pharmacology of Reynoutria genus

Objectives

The genus Reynoutria belonging to the family Polygonaceae is widely distributed in the north temperate zone and used in folk medicine. It is administered as a sedative, tonic and digestive, also as a treatment for canities and alopecia. Herein, we reported a review on traditional uses, phytochemistry and pharmacology reported from 1985 up to early 2022. All the information and studies concerning Reynoutria plants were summarized from the library and digital databases (e.g. ScienceDirect, SciFinder, Medline PubMed, Google Scholar, and CNKI).

Key findings

A total of 185 articles on the genus Reynoutria have been collected. The phytochemical investigations of Reynoutria species revealed the presence of more than 277 chemical components, including stilbenoids, quinones, flavonoids, phenylpropanoids, phospholipids, lactones, phenolics and phenolic acids. Moreover, the compounds isolated from the genus Reynoutria possess a wide spectrum of pharmacology such as anti-atherosclerosis, anti-inflammatory, antioxidative, anticancer, neuroprotective, anti-virus and heart protection.

Summary

In this paper, the traditional uses, phytochemistry and pharmacology of genus Reynoutria were reviewed. As a source of traditional folk medicine, the Reynoutria genus have high medicinal value and they are widely used in medicine. Therefore, we hope our review can help genus Reynoutria get better development and utilization.

Fuzhuan Brick Tea Boosts Melanogenesis and Prevents Hair Graying through Reduction of Oxidative Stress via NRF2-HO-1 Signaling

The anti-graying effect of the hexane fraction of Fuzhuan brick tea is investigated in Melan-A cells and C57BL/6 mice. As a result, it is found that reactive oxygen species-induced damage is associated with the reduction of melanogenesis in hair bulb melanocytes when reactive oxygen species generation in Melan-A cells occurred. The results revealed that the hexane fraction of Fuzhuan brick tea could remarkably reduce reactive oxygen species generation in Melan-A cells; meanwhile, it could increase the cellular tyrosinase and melanin content, as well as up-regulate the expression of tyrosinase, tyrosinase related protein-1, tyrosinase related protein-2, and microphthalmia-associated transcription factor, and activate the MAP-kinase pathway through activating the phosphorylation of p38 c-Jun N terminal kinase/extracellular signal-regulated kinase. Furthermore, high-pressure liquid chromatography analysis reveals that the tea's major ingredients in hexane fraction include gallic acid, theaflavin, theobromine, caffeine, epicatechin, and quercetin. Together, the current results suggest that Fuzhuan brick tea proves to protect from the damage of hydroquinone, which induces hair pigment loss.

Simultaneously screening multiple UGT1A1 inhibitors from Polygonum multiflorum root using ultrafiltration liquid chromatography-mass spectrometry

The liver injury induced by Polygonum multiflorum root (PMR) is an urgent issue requiring wide spread attention. UDP-glucuronosyltransferase 1A1 (UGT1A1) inhibitors are suspected to additively contribute to the hepatotoxicity of PMR. This study was deliberately designed to simultaneously screen the UGT1A1 inhibitors from PMR and their co-contribution to the hepatotoxicity was evaluated. With ultrafiltration coupled to liquid chromatography-mass spectrometry method, four compounds namely cis-2,3,5,4'-tetrahydroxystilbene-2-O-β-glucoside, trans-2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside, emodin-8-O-β-D-glucoside and emodin were screened out, displaying the in vitro inhibitory activities against UGT1A1 with IC₅₀ values of 76.23, 18.70, 62.18, 34.02 μM, respectively. The varying activities of screened UGT1A1 inhibitors were explained by performing a molecular docking simulation. Finally, zebrafish larvae and mice assays demonstrated that the UGT1A1 inhibitors co-contributed to the hepatotoxicity of PMR. Hopefully, these findings are conducive to understand the acting role of UGT1A1 inhibitors in PMR-induced hepatotoxicity.

Polygonum multiflorum Thunb. Extract Stimulates Melanogenesis by Induction of COX2 Expression through the Activation of p38 MAPK in B16F10 Mouse Melanoma Cells

Polygonum multiflorum Thunb. (PM) root extracts have been used for treating graying hair in Oriental medicine; however, the molecular mechanisms underlying the melanogenic effects of PM root have not been fully understood. In the present study, we investigated the melanogenic effects of an ethanolic extract of PM root (PME) and the mechanisms involved. We examined the effects of PME on cell viability, cellular melanin content, and tyrosinase activity in B16F10 cells. The melanogenic mechanism of PME was explored using signaling inhibitors and examining the expression of melanogenic genes and signaling molecules by western blot and RT-qPCR analyses. PME did not exhibit any cytotoxicity in B16F10 cells compared to that in control cells. PME treatment significantly increased melanin production and tyrosinase activity. In addition, PME induced the expression of cyclooxygenase-2 (COX2) as well as that of melanogenic genes, such as microphthalmia-associated transcription factor (MiTF), tyrosinase-related protein (Trp) 1, Trp2, and tyrosinase, in B16F10 cells. PME treatment increased the level of phosphorylated p38 mitogen-activated protein kinase (MAPK), and pretreatment with SB 203580, a p38 MAPK inhibitor, significantly suppressed this PME-induced increase in the expression of COX2 and melanogenic genes. These results indicate that PME induced the expression of melanogenic genes by inducing COX2 expression via the activation of the p38 MAPK pathway, thereby contributing to the enhancement of melanogenesis.

Effects of Processed Polygonum multiflorum with KIOM Patent on Bone Remodeling-Related Protein Expression in Human Osteoblast-Like SaOS-2 Cells

This present study evaluated the effects of processed P. multiflorum on osteogenesis using Sarcoma osteogenic (SaOS-2) cell lines and osteoclastogenesis of bone marrow-derived macrophage cells (BMM) and to elucidate differences in effect on the expression of bone-related proteins between commercially sold P. multiflorum and patented, in vitro-propagated Korea Institute of Oriental Medicine (KIOM) P. multiflorum. Raw P. multiflorum and P. multiflorum that were stir-baked and steamed in black bean juice were compared, and western blotting analysis was performed to investigate the expression of bone remodeling-related proteins in SaOS-2 cells. In the cells treated with P. multiflorum steamed in black bean juice, the expression of RANKL was decreased, whereas that of osteoprotegerin, alkaline phosphatase, Runx2, and osterix was increased. Owing to these results, we conclude that processed P. multiflorum can be used as an alternative treatment for bone diseases such as osteoporosis, osteopenia, periodontitis, and Paget's disease.

Eriodictyon angustifolium extract, but not Eriodictyon californicum extract, reduces human hair greying

OBJECTIVE

Yerba Santa (Eriodictyon angustifolium and Eriodictyon californicum) has been used for many years in traditional medicine. However, the effect of Yerba Santa on melanogenesis has not yet been investigated. We aimed to assess the biological effects of Yerba Santa on hair pigmentation.

METHODS

Yerba Santa extracts were assessed for their cytological effects following X-ray irradiation treatment and then tested directly for the prevention of human hair greying. Ultra-performance liquid chromatography (UPLC) was utilized to identify the individual extract components.

RESULTS

Eriodictyon angustifolium extract significantly increased melanin synthesis in the melanoma cell line through activation of the WNT/MITF/tyrosinase-signalling pathway. In contrast, E. californicum had no effect on melanin synthesis. E. angustifolium extract also demonstrated a protective effect against the damage induced by X-ray irradiation in human keratinocytes. Application of the extracts to subjects who had grey beards demonstrated a reduced number of grey beard hair per year specifically with the E. angustifolium extract. A significant decrease in grey head hair was also observed after application of E. angustifolium extract. Upregulation of gene expression related to melanin production and WNT signalling was observed after the application of E. angustifolium extract. Sterubin was the most abundant flavonoid detected by UPLC in E. angustifolium extract. In addition, sterubin showed the highest difference in terms of quantity, between E. angustifolium and E. californicum extract.

CONCLUSION

Eriodictyon angustifolium extract, which is abundant in sterubin, may be suitable as a potential cosmetic and medical agent for the prevention and improvement of hair greying.

Pigmentation Effect of Rice Bran Extract in Hair Follicle-Like Tissue and Organ Culture Models

BACKGROUND

Melanogenesis is a biological process resulting in the production of melanin pigment, which plays an important role in the prevention of sun-induced skin injury and determines the hair and skin color. Melanin has the ability to block ultraviolet radiation and scavenge free oxygen radicals, thus protecting the skin from their harmful effects. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. Hence, various approaches have been proposed to increase the synthesis of melanin.

METHODS

The current study aimed to develop a three-dimensional hair follicle-like tissue (HFLT) model with human dermal papilla, melanocytes, and outer root sheaths cells. This model showed enhanced melanogenesis-related protein expression after rice bran ash extract (RBE) treatment. Next, we investigated the melanogenic effect of RBE in the HFLT and compared the results to those of hair follicle (HF) organ culture model.

RESULTS

RBE was found to significantly increase the expression of microphthalmia-associated transcription factor, a key transcription factor involved in melanin production, in both HFLT and organ culture models. Results showed that melanogenesis-related protein expression levels were higher in the RBE group compared to those in the control group. Similar results were obtained by immunohistochemistry.

CONCLUSION

Our data suggested that RBE promotes melanin biosynthesis. Taken together, this simple in vitro HFLT model system has the potential to provide significant insights into the underlying molecular mechanisms of HF melanogenesis, and hence can be used for controlled evaluation of the efficacy of new materials for melanogenesis.