Protective effect of Pinus massoniana needle extract against oxidative stress in human dermal papilla cells via the nuclear factor-erythroid 2-related factor 2-antioxidant responsive element signaling pathway / 中华皮肤科杂志

Objective:To investigate protective effect of Pinus massoniana needle extract (PMNE) against oxidative stress in human dermal papilla cells (HDPC) , and to explore its mechanisms. Methods:As research objects, some cultured HDPC were treated with H 2O 2 at different concentrations of 0 (control group) , 0.1, 0.2, 0.4, 0.8 and 1.0 mmol/L, in order to establish the optimal condition for in vitro oxidative stress in HDPC; some other HDPC were transfected with nuclear factor-erythroid 2-related factor 2 (Nrf2) specific small interfering RNAs (siRNA1, siRNA2, siRNA3) or a Nrf2-overexpressing plasmid (pCMV6-XL5-Nrf2) , the HDPC transfected with a scrambled-siRNA and an empty plasmid pCMV6-XL5 served as the control siRNA group and control plasmid group respectively, and HDPC subjected to conventional culture served as the blank group; after the above treatment, real-time fluorescence-based quantitative PCR and Western blot analysis were performed to determine Nrf2 mRNA and protein expression, respectively; cell viability and apoptosis were detected in the above transfected cells after the treatment with H 2O 2 at an optimal concentration. In the subsequent experiment, some HDPC were divided into several groups: control group subjected to conventional culture, dihydrotestosterone group treated with 0.03 μg/ml dihydrotestosterone, proanthocyanidin group treated with 0.03 μg/ml dihydrotestosterone and 6.00 μg/ml proanthocyanidin B2, PMNE groups treated with 0.03 μg/ml dihydrotestosterone and PMNE at different concentrations of 1, 5, 25 and 100 μg/ml; after the above treatment, cell viability and apoptosis were detected, relative fluorescence intensity of intracellular reactive oxygen species (ROS) , malondialdehyde (MDA) content, mRNA and protein expression of Nrf2, quinone oxidoreductase 1 (NQO1) , heme oxygenase 1 (HO-1) , Kelch-like ECH-related protein 1 (Keap1) , transforming growth factor (TGF) -β1, Sma- and Mad-related protein 2/3 (Smad2/3) , phosphorylated Smad2/3 (p-Smad2/3) were determined in HDPC. One-way analysis of variance was used for comparisons among multiple groups, and least significant difference- t test for multiple comparisons. Results:The viability of HDPC ranged from 75% to 85% after the treatment with 0.4 mmol/L H 2O 2, which was selected as the optimal condition for in vitro oxidative stress in HDPC. Compared with the blank group and control siRNA group, the Nrf2-siRNA1, Nrf2-siRNA2, Nrf2-siRNA3 groups showed significantly decreased Nrf2 mRNA and protein expression (all P < 0.05) , but significantly increased apoptosis rate (Nrf2-siRNA1, Nrf2-siRNA2, Nrf2-siRNA3 groups, blank group and control group: 12.50% ± 0.05%, 26.07% ± 0.05%, 58.44% ± 1.03%, 10.38% ± 0.64%, 13.05% ± 0.12%, respectively; all P < 0.05) . Nrf2 protein expression was the lowest in the Nrf2-siRNA2 group, so Nrf2-siRNA2 was selected as the optimal interfering fragment for subsequent experiments. Compared with the blank group and control plasmid group, the Nrf2 overexpression group showed significantly increased Nrf2 mRNA and protein expression (both P < 0.05) , but a significantly decreased apoptosis rate (all P < 0.05) . After the treatment with 0.4 mmol/L H 2O 2, the Nrf2 overexpression group showed a significantly decreased apoptosis rate, but significantly increased cell viability compared with the empty vector group ( t = 3.66, 40.40, respectively, both P < 0.001) ; the Nrf2-siRNA2 group showed a significantly increased apoptosis rate, but significantly decreased cell viability compared with the control group ( t = 13.13, 67.37, respectively, both P < 0.001) . In the PMNE treatment experiment, the proanthocyanidin group and PMNE groups showed significantly increased cell viability, but significantly decreased apoptosis rates compared with the dihydrotestosterone group (all P < 0.01) ; proanthocyanidin and PMNE at different concentrations could significantly inhibit dihydrotestosterone-induced overexpression of ROS and MDA in HDPC (all P < 0.01) ; the protein expression of Nrf2, NQO1 and HO-1 was significantly higher in the proanthocyanidin group, 5-, 25- and 100-μg/ml PMNE groups than in the dihydrotestosterone group (all P < 0.05) , while the protein expression of Keap1 and TGF-β1, and the Smad2/3 phosphorylation level were significantly lower in the proanthocyanidin group, 25- and 100-μg/ml PMNE groups than in the dihydrotestosterone group (all P < 0.05) . Conclusion:Nrf2 plays an important role in protecting against oxidative damage in HDPC, and PMNE may exert marked protective effect on HDPC by activating the Nrf2-antioxidant responsive element signaling pathway.

Various Wavelengths of Light-Emitting Diode Light Regulate the Proliferation of Human Dermal Papilla Cells and Hair Follicles via Wnt/β-Catenin and the Extracellular Signal-Regulated Kinase Pathways

BACKGROUND: The human dermal papilla cells (hDPCs) play an important role in regulation of hair cycling and growth. OBJECTIVE: The aim of this study was to investigate the effect of different wavelengths of light-emitting diode (LED) irradiation on the proliferation of cultured hDPCs and on the growth of human hair follicles (HFs) in vitro. METHODS: We examined the effect of LED irradiation on Wnt/β-catenin signaling and mitogen-activated protein kinase (MAPK) pathways in hDPCs. Anagen HFs were cultured with LED irradiation and elongation of each hair shaft was measured. RESULTS: The most potent wavelength in promoting the hDPC proliferation is 660 nm and 830 nm promoted hDPC proliferation to a lesser extent than 660 nm. Various wavelengths significantly increased β-catenin, Axin2, Wnt3a, Wnt5a and Wnt10b mRNA expression. LED irradiation significantly increased β-catenin and cyclin D expression, and the phosphorylation of MAPK and extracellular signal-regulated kinase (ERK). HFs irradiated with 415 nm and 660 nm grew longer than control. CONCLUSION: Our result suggests that LED has a potential to stimulate hDPC proliferation via the activation of Wnt/β-catenin signaling and ERK pathway. To our best knowledge, this is the first report which investigated that the effect of various wavelengths of LED on hDPC proliferation and the underlying mechanisms.

Epigallocatechin Gallate-Mediated Alteration of the MicroRNA Expression Profile in 5α-Dihydrotestosterone-Treated Human Dermal Papilla Cells

BACKGROUND: Dihydrotestosterone (DHT) induces androgenic alopecia by shortening the hair follicle growth phase, resulting in hair loss. We previously demonstrated how changes in the microRNA (miRNA) expression profile influenced DHT-mediated cell death, cell cycle arrest, cell viability, the generation of reactive oxygen species (ROS), and senescence. Protective effects against DHT have not, however, been elucidated at the genome level. OBJECTIVE: We showed that epigallocatechin gallate (EGCG), a major component of green tea, protects DHT-induced cell death by regulating the cellular miRNA expression profile. METHODS: We used a miRNA microarray to identify miRNA expression levels in human dermal papilla cells (DPCs). We investigated whether the miRNA expression influenced the protective effects of EGCG against DHT-induced cell death, growth arrest, intracellular ROS levels, and senescence. RESULTS: EGCG protected against the effects of DHT by altering the miRNA expression profile in human DPCs. In addition, EGCG attenuated DHT-mediated cell death and growth arrest and decreased intracellular ROS levels and senescence. A bioinformatics analysis elucidated the relationship between the altered miRNA expression and EGCG-mediated protective effects against DHT. CONCLUSION: Overall, our results suggest that EGCG ameliorates the negative effects of DHT by altering the miRNA expression profile in human DPCs.

Expression of specific marker molecules of long-term cultured human dermal papilla cells in vitro / 中华医学美学美容杂志

Objective To investigate the expression of specific marker molecules in hair-inducing activity of long-term cultured human dermal papilla cells (HDPCs) in vitro.Methods After dissected and cultured the HDPCs in vitro,the cells of passages 1 to 8 were used for experiments.The growth appearances of HDPCs in different passages were observed under inverted microscope.To detect the expression of specific marker molecules of long-term cultured HDPCs,the alkaline phosphatase (ALP) activity of the HDPCs was examined,and the specific genes ALP and insulin-like growth factor-1 (IGF-1) expression levels of HDPCs were determined by real-time quantitative PCR.Results After long-term cultured in vitro,the ALP and IGF-1 expression levels of HDPCs gradually decreased in different passages,as well as the display of the aggregated and cartouche growth.The ALP and IGF-1 expression levels of HDPCs in passage 1 was the highest,they were almost about 6.8-fold and 3.5-fold higher than the HDPCs in passage 8.The ALP staining of the HDPCs in passage 1 and passage 2 were evident,but the cells' ALP staining gradually became much weaker than the cells in the previous passages after the long-term cultured in vitro.Conclusions The expression levels of specific marker molecules ALP and IGF-1 of the HDPCs decrease gradually after long-term cultured in vitro,and the higher passage HDPCs lost the special aggregated and cartouche growth appearance,and hence lead to the loss of hair-inducing activity of HDPCs.