Γιωργοςbioherbal
Active Member
Εδω μπορουμε να διαβασουμε ακριβως την συνεντευξη του Κωτσαρελη που παρεθεσε γιαυτο το Θεμα.
then Luis worked with mouse models to assess the function of PGD2. Luis applied the PGD2 and another breakdown product, PGJ2, topically to the back of a mouse and he showed that hair growth slowed. Next, we collaborated with another group that was good at growing human hair follicles in culture. They showed that PGD2 in the culture media slowed down hair growth. So now we had functional evidence that prostaglandins played a role in hair growth. Luis also looked in the mouse, which has a better-defined hair cycle than humans because all of the hairs tend to be in the same stage whereas humans have mixtures of hair follicles in different stages of growth. In that model we showed that PGD2 started to go up during the end of the growing phase and was highest at catagen, the stage of regression. That, again, was good correlative evidence that PGD2 was inhibiting hair growth and even in a spontaneous hair cycle played a role in controlling hair growth.
There was a mouse that was made in the ’90s by Sue Fisher, who studies skin cancer; it’s a transgenic mouse that makes the COX-2 enzyme in the skin, so you drive COX-2 gene expression with keratin K14 promoters. It’s up higher in the pathway so if you overexpress COX-2 you get increases in PGD2 and also PGE2. E2 and F2 are actually known to promote hair growth — bimatoprost (Latisse) is an F2 analog. We looked at levels of D2 in that mouse, which develops alopecia, and they were sky high. E2 was also higher than the control but D2 levels were much higher. What’s amazing is if you looked at that mouse’s skin histologically the hair follicles were miniaturized and the sebaceous glands were enlarged, just like in androgenetic alopecia.
Finally, in genetic experiments done in collaboration with FitzGerald, we applied D2 to mice that lacked two different receptors that D2 binds to. The DP-1 knockout mouse had suppressed hair growth. The DP-2 (or GPR44) knockout mouse did not have inhibited hair growth.
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