Comprehensive Analysis of LncRNA AC010789.1 Delays Androgenic Alopecia Progression by Targeting MicroRNA-21 and the Wnt/β-Catenin Signaling Pathway in Hair Follicle Stem Cells

Dahuang-Gancao decoction ameliorates testosterone-induced androgenetic alopecia in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Dahuang-Gancao decoction (DGD) is a traditional Chinese medicinal formula that is recorded in the Synopsis of the Golden Chamber, and is widely used to treat damp-heat in the body. Since the pathological factors of androgenetic alopecia (AGA) also reflect damp-heat blockage, DGD has great potential for the treatment of AGA and has been used effectively in clinical practice.

AIM OF THE STUDY

The aim of the study was to investigate whether external application of DGD could promote the activation and proliferation of hair follicle stem cells (HFSCs) and improve AGA through the Wnt/β-catenin pathway.

MATERIALS AND METHODS

The main chemical components of DGD-contained serum were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and database search. Cell Counting Kit-8 (CCK8) was used to investigate the appropriate concentration. Hair regeneration was assessed by hair growth score and histopathological staining. The proliferation of HFSCs and the activation of Wnt/β-catenin pathway were detected by Western blot, immunofluorescence staining, real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and enzyme-linked immunosorbent assay (ELISA). The AGA mouse model was induced by external application of testosterone (T). Immunofluorescence staining was performed to localize HFSCs by CK15, followed by staining with Ki67, β-catenin, and Cyclin D1, respectively.

RESULTS

The results illustrated that the 10% DGD group and the 10% DGD + HLY78 group could significantly promote the expression of Wnt10b and β-catenin and the proliferation of HFSCs in vitro, while the 10% DGD + IWR-1 group could reverse the promotion effect of DGD. Animal experiments showed that compared with the model group (T group), DGD promoted hair follicles to enter the anagen phase, as evidenced by an increase in hair growth score, an increase in the number of hair follicles in hematoxylin and eosin (HE) staining, and a significant increase in the ratio of the number of anagen follicles to the total number of hair follicles (AF/AF + TF). In addition, DGD upregulated the expression of Wnt/β-catenin signaling pathway proteins in the skin tissues of AGA mice. It also promoted the proliferation of HFSCs and the expression of β-catenin and Cyclin D1 cytokines in the region of HFSCs.

CONCLUSION

Both oral and external application of DGD can promote the proliferation of HFSCs by activating the Wnt/β-catenin signalling pathway. External application of DGD can promote the hair follicles to enter the anagen phase, which can ameliorate the symptoms of alopecia in AGA mice. Therefore, compared to oral DGD, external application of DGD is an effective and safer way of administration for the treatment of AGA.

Exosome-derived long non-coding RNA AC010789.1 modified by FTO and hnRNPA2B1 accelerates growth of hair follicle stem cells against androgen alopecia by activating S100A8/Wnt/β-catenin signalling

BACKGROUND

The increased incidence of androgenic alopecia (AGA) causes adverse physiological and psychological effects on people of all genders. The hair follicle stem cells (HFSCs) have displayed clinical improvements on AGA. However, the molecular mechanism of HFSCs against AGA remains elusive.

METHODS

The expression and prognosis of lncRNA AC010789.1 in AGA hair follicle tissues were assessed by qRT-PCR analysis. CCK-8, EdU and Transwell analysis were utilized to assess cell growth. The specific binding between AC010789.1 and FTO mediated m6A modification or the effect of AC010789.1 on hnRNPA2B1, S100A8 and Wnt/β-catenin signaling expression was confirmed by bioinformatic analysis, RIP, RNA pull-down and Western blot assay. The effects of Exosome-loaded AC010789.1 prompted HFSCs proliferation and hair follicle regeneration were confirmed in hairless mice.

RESULTS

We herein found that the mRNA levels of lncRNA AC010789.1 were decreased in AGA tissue samples but increased in HFSCs of surrounding normal tissue samples. Overexpression (OE) of AC010789.1 promoted HFSC proliferation, DNA synthesis and migration as well as K6HF and Lgr5 upregulation, whereas knockdown of AC010789.1 showed the opposite effects. The total or AC010789.1 m6A levels were reduced and FTO demethylase was upregulated in AGA tissue samples, but these indicated the reverse results in HFSCs of surrounding normal tissue samples. FTO OE decreased AC010789.1 m6A levels and its mRNA levels in HFSCs and abolished AC010789.1-induced HFSCs proliferation. In addition, AC010789.1 was identified to bind to m6A reader hnRNPA2B1, which was downregulated in AGA but upregulated in HFSCs of surrounding normal tissue samples. hnRNPA2B1 OE attenuated AC010789.1 knockdown-induced inhibition of HFSCs proliferation. Moreover, AC010789.1 could bind to and enhance downstream S100A8 protein expression, which mediated Wnt/β-catenin signaling to accelerate HFSCs proliferation. Exosome-loaded AC010789.1 prompted HFSCs proliferation and hair follicle regeneration in mice.

CONCLUSIONS

Our findings demonstrated that exosome-derived lncRNA AC010789.1 modified by FTO and hnRNPA2B1 facilitated the proliferation of human HFSCs against AGA by activating S100A8/Wnt/β-catenin signaling.

KEY POINTS

Long non-coding RNA (lncRNA) AC010789.1 was downregulated in hair follicle tissues from androgenic alopecia (AGA) and upregulated in hair follicle stem cells (HFSCs). LncRNA AC010789.1 promoted the proliferation and migration of HFSCs. FTO/hnRNPA2B1-mediated m6A modification of lncRNA AC010789.1 promoted HFSCs growth by activating S100A8/Wnt/β-catenin signalling. Exosome-derived AC010789.1 accelerated HFSCs proliferation.

Construction of regulatory network for alopecia areata progression and identification of immune monitoring genes based on multiple machine-learning algorithms

Objectives

Alopecia areata (AA) is an autoimmune-related non-cicatricial alopecia, with complete alopecia (AT) or generalized alopecia (AU) as severe forms of AA. However, there are limitations in early identification of AA, and intervention of AA patients who may progress to severe AA will help to improve the incidence rate and prognosis of severe AA.

Methods

We obtained two AA-related datasets from the gene expression omnibus database, identified the differentially expressed genes (DEGs), and identified the module genes most related to severe AA through weighted gene co-expression network analysis. Functional enrichment analysis, construction of a protein-protein interaction network and competing endogenous RNA network, and immune cell infiltration analysis were performed to clarify the underlying biological mechanisms of severe AA. Subsequently, pivotal immune monitoring genes (IMGs) were screened through multiple machine-learning algorithms, and the diagnostic effectiveness of the pivotal IMGs was validated by receiver operating characteristic.

Results

A total of 150 severe AA-related DEGs were identified; the upregulated DEGs were mainly enriched in immune response, while the downregulated DEGs were mainly enriched in pathways related to hair cycle and skin development. Four IMGs (LGR5, SHISA2, HOXC13, and S100A3) with good diagnostic efficiency were obtained. As an important gene of hair follicle stem cells stemness, we verified in vivo that LGR5 downregulation may be an important link leading to severe AA.

Conclusion

Our findings provide a comprehensive understanding of the pathogenesis and underlying biological processes in patients with AA, and identification of four potential IMGs, which is helpful for the early diagnosis of severe AA.

Investigation of hub genes and immune infiltration in androgenetic alopecia using bioinformatics analysis

Background

Androgenetic alopecia (AGA) is a type of non-scarring hair loss. Current drugs for AGA are accompanied by adverse reactions and a high recurrence rate. Thus, the discovery of diagnostic biomarkers and therapeutic targets for AGA remains imperatively warranted.

Methods

The GSE90594 dataset, which contained scalp skin biopsies from 14 male AGA cases and healthy volunteers, was used to identify the differentially expressed genes (DEGs). Functional enrichment analysis was subsequently performed. Next, the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) database combined with the cytoHubba plugin of Cytoscape were used to obtain the key genes of AGA. Thereafter, the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm was performed to evaluate the relative abundance of immune cells between male AGA patients and healthy controls. The correlation between key genes and infiltrating immune cells was analyzed to obtain the significant immune-cell related genes (IRGs), then intersected with the DEGs between immortalized balding and non-balding human dermal papilla cells (DPCs) of the GSE93766 dataset as well as the DEGs obtained by the GSE90594 dataset, thus obtaining the hub genes of AGA. Finally, the hub genes were validated using GSE36169, which contained expression profiling of tissues biopsied from haired and bald scalps of five individuals with AGA.

Results

A total of 234 DEGs were obtained from the GSE90594 dataset, which were mainly enriched in the extracellular matrix (ECM)-related pathways and immune-related activities. The STRING database and ten algorithms in the cytoHubba plugin of Cytoscape disclosed 21 key DEGs. The results of the CIBERSORT algorithm revealed the relative abundances of 20 kinds of immune cells between diseased and healthy individuals, and yielded 15 IRGs involved in the pathogenesis of AGA. Next, the intersection analysis identified four hub genes of AGA, comprising COL1A2, PCOLCE, ITGAX, and LOX. The GSE36169 dataset validated the expression pattern of hub genes in the haired scalp of AGA patients.

Conclusions

We discovered that the hub genes identified are closely linked with the causative factors of AGA, which could be used as the viable diagnostic and therapeutic target in the clinical applications.

Effect of Sun exposure-induced ferroptosis mechanisms on pathology and potential biological processes of primary melanoma by microarray data analysis

Objectives: Sunlight exposure is an important environmental factor in the pathogenesis of skin cutaneous melanoma (SKCM). Ultraviolet (UV) from sunlight can cause excessive intracellular production of reactive oxygen species (ROS), resulting in damage from oxidative stress to cells. As a major iron-rich and ROS-producing organelle, mitochondria are considered as an important place for cell ferroptosis. Thus, the pathology and potential biological process of UV exposure-induced ferroptosis in the development of SKCM has aroused our strong interest.

Methods: Gene expression profile datasets of melanoma cell line datasets (GSE31909) and UV-irradiated mitochondria dataset (GSE3632) were downloaded from the Gene Expression Omnibus (GEO) database, and ferroptosis-related genes were obtained from the FerrDb v2 database. After identifying the common differentially expressed genes (DEGs), comprehensive analyzes were performed, including functional annotation, protein-protein interaction (PPI) network construction, hub gene identification, and gene and tissue protein expression levels, survival analysis, and immune cell infiltration analysis.

Results: A total of 14 common DEGs was identified for subsequent analyses. Seven DEGs, including PSMB4, CRELD2, CDKN2A, TIMP1, NDRG1, ATF3 and JUND, have consistent performance in mRNA and protein expression in normal skin and SKCM tissues can be regarded as a good biomarker with SKCM diagnostic effectiveness. Functional enrichment analysis results indicate that HIF-1 signaling pathway and angiogenesis involved in the pathogenesis and development of SKCM. Induction of ferroptosis in tumor cells by enhancing the function of CD8+ T cells is expected to be an effective intervention to promote tumor therapy.

Conclusion: Our study reveals the pathogenesis and potential biological processes of UV exposure-induced ferroptosis in the development of SKCM, which may provide potential immunotherapy targets for SKCM treatment via tumor cell ferroptosis mechanisms.

Morphogenesis, Growth Cycle and Molecular Regulation of Hair Follicles

As one of the main appendages of skin, hair follicles play an important role in the process of skin regeneration. Hair follicle is a tiny organ formed by the interaction between epidermis and dermis, which has complex and fine structure and periodic growth characteristics. The hair growth cycle is divided into three continuous stages, growth (anagen), apoptosis-driven regression (catagen) and relative quiescence (telogen). And The Morphogenesis and cycle of hair follicles are regulated by a variety of signal pathways. When the signal molecules in the pathways are abnormal, it will affect the development and cycle of hair follicles, which will lead to hair follicle-related diseases.This article will review the structure, development, cycle and molecular regulation of hair follicles, in order to provide new ideas for solving diseases and forming functional hair follicle.