MicroRNAs contribute to hair loss and follicle regression

c_super2 · Jun 16, 2015

http://blogs.plos.org/biologue/2015...tribute-to-hair-loss-and-follicle-regression/

benjt · Jun 17, 2015

This could perhaps finally be the missing link in the chain between DHT and PGD2 which ultimately leads to male pattern baldness.

Swoop · Jun 21, 2015

Mir-22 is linked to senescence but also to apoptosis as mentioned (there are more studies about this);

http://jcb.rupress.org/content/193/2/409.abstract

Cellular senescence acts as a barrier to cancer progression, and microRNAs (miRNAs) are thought to be potential senescence regulators. However, whether senescence-associated miRNAs (SA-miRNAs)contribute to tumor suppression remains unknown. Here, we report that miR-22, a novel SA-miRNA, has an impact on tumorigenesis. miR-22 is up-regulated in human senescent fibroblasts and epithelial cells but down-regulated in various cancer cell lines.

There are other studies too in relation to microRNAs. Here for example one with a comparison of nonbalding vs balding DPC;

http://www.ncbi.nlm.nih.gov/pubmed/21967250

We detected the significant upregulation of miR-221, miR-125b, miR-106a and miR-410 in balding papilla cells.

another one;

http://www.ncbi.nlm.nih.gov/pubmed/25778683

Abstract
Clinical evidence has demonstrated that the accumulation of 5?-dihydrotestosterone (DHT) in dermal papilla cells (DPCs) is implicated in androgenetic alopecia. Whether this accumulation in DHT may have direct cellular effects leading to androgenetic alopecia remains to be elucidated. The present study aimed to determine whether DHT affects cell growth, cell cycle arrest, cell death, senescence and the induction of reactive oxygen species (ROS), and whether these effects are mediated by microRNA (miRNA)-dependent mechanisms. The cell viability and cell cycle were determined, levels of ROS were examined and senescence-associated ?-galactosidase assays were performed in normal human DPCs (nHDPCs). Furthermore, miRNA expression profiling was performed using an miRNA microarray to determine whether changes in the expression levels of miRNA were associated with the cellular effects of DHT. The results revealed that DHT decreased cell growth by inducing cell death and G2 cell cycle arrest, and by increasing the production of ROS and senescence in the nHDPCs. In addition, 55 miRNAs were upregulated and 6 miRNAs were downregulated in the DHT-treated nHDPCs. Bioinformatic analysis demonstrated that the putative target genes of these upregulated and downregulated miRNAs were involved in cell growth, cell cycle arrest, cell death, senescence and the production of ROS. Specifically, the target genes of five highly upregulated and downregulated miRNAs were identified and were associated with the aforementioned effects of DHT. These results demonstrated that the expression of miRNA was altered in the DHT-treated nHDPCs and suggest the potential mechanisms of DHT-induced cell growth repression, cell cycle arrest, cell death, senescence and induction of ROS.

Makes you wonder if a drug if even realistically imaginable as a cure (reversal Androgenetic Alopecia). Probably not.