"In the hair bulb, Notch controls cell differentiation, ensuring the proper development of every layer of the hair shaft and inner root sheath"
https://www.ncbi.nlm.nih.gov/books/NBK45997/
"Hair follicle morphogenesis depends on Wnt, Shh, Notch, BMP and other signaling pathways interplay between epithelial and mesenchymal cells"
"This interplay of signaling between the epithelial and dermal lineage helps in epithelial Shh signal amplification. The dermal Wnt pathway helps in upregulation of epithelial Notch expression. Dysregulation of these pathways leads to certain abnormalities"
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3907891/
"The most significant pathway altered in Androgenetic Alopecia is Notch Signaling"
"The down regulated genes in this pathway in Androgenetic Alopecia include CNTN1, JAG1, NOTCH2 and PSEN1 and the genes that are up regulated include DTX3, HES and NOTCH4. The expression patterns of Notch signaling pathway genes including Notch 2 and JAG1 were validated by real-time PCR (
Figure S1). Jagged1 (JAG1) gene which encodes a ligand for Notch receptor maps to chromosome 20p a susceptibility locus for male-pattern baldness [
8]. A reciprocal negative feedback regulation exists between Notch and AR-dependent pathways in the prostate [
9]. The activation of AR and the concomitant loss of Notch signaling may be contributing factors to hair follicle miniaturization and may serve as the mechanistic link between prostate cancer and Androgenetic Alopecia.
Thus, modulating the Notch signaling pathway in Androgenetic Alopecia may lead to future therapies." year 2013...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4164265/
They then showed that removing Tregs from the skin significantly reduced Notch signaling in follicle stem cells, and that replacing Tregs with microscopic beads covered in
Jag1 protein restored Notch signaling in the stem cells and successfully activated follicle regeneration."