[Lotus]

My observation FWIF (unscientific) for optimal serum hormone levels goes like this:

NBE
E2 150-200 pg/ML
Total T 100-200 ng/dL (below this and libidos tank)
SHBG 66 nnmol/L



   


HRT
E2 400-800 (emulates menstrual cycles)
Total T 25 and below ng/dL (chemical castration)
SHBG 80 nnmol/L

Deny DHT's pathway (as much as possible) at the top of the chain (P450 family of enzymes) seems viable. Classic and side/backdoor leakage of DHT means we're chasing a fathom ghost inhibiting it. And it's time to go ghost hunting lol.


Metabolism of Testosterone, Dihydrotestosterone, Estrone and Estradiol
http://www.ergogenics.org/anabolenboek/index11en.html
The biosynthesis of the sex hormones starts with the oxidation of the side chain of cholesterol, which is catalyzed by the enzyme cytochrome P450scc. This cytochrome P450 oxidizes the side chain on C20 and C22 by the introduction of two hydroxyl groups. After that the chain is broken in between these two atoms by the same enzyme, under formation of pregnenolone.

The next steps in the biosynthesis of testosterone can proceed via two different routes. Pregnenolone can be oxidised first by cytochrome P45017a to 17a-hydroxypregnenolone. This route is known as the 5-ene route because all biosynthetic intermediates in this route possess a D5-double bond.

The enzyme 3b-HSD also can convert pregnenolone first into progesterone by oxidation of the 3b-hydroxy group followed by a shift of the double bond from the C5-C6 to the C4-C5 position. This route is known as the 4-ene route because here all biosynthetic intermediates possess a D4-double bond.

The reduction of testosterone takes place in target tissues like the prostate and the skin and of course metabolism takes place in the liver. In male a very small part (0.2%) of the testosterone is converted into estradiol. This process mainly takes place in adipose tissue and for about 20% in the testes.

The metabolisme of testosterone and dihydrotestosterone takes place for 90% in the liver. There reductases and dehydrogenases catalyse the reactions of the D4-double bond, the C3-carbonyl group and the C17-hydroxyl group. Finally the hydroxyl groups are connected to glucuronic acid or sulphate, followed by excretion with the urine [3] [4].


The biosynthesis of the female sex hormones starts from A-dione and can proceed by two different routes (see Scheme 2). The C17 carbonyl group in A-dione can be reduced first to a 17b-hydroxyl group under formation of testosterone, followed by oxidation and removal of the C19 methyl group and aromatisation of ring A.

The oxidation and removal of the C19 methyl group and the aromatisation of ring A can take place also first, under formation of estrone. Reduction of the carbonyl group at C17 then gives estradiol.

The oxidation of the C19 methyl group is catalyzed by a complex of cytochrome P450 enzymes, indicated with the code P450aromatase or simply as aromatase. The methyl group is first oxidized to a hydroxyl group and than to a carbonyl group (an aldehyde). The removal of this group together with a H-atom from C1 than leads to aromatisation of ring A. An important step in this aromatisation process is the fission of the C10-C19 bond. Also this reaction proceeds in only one direction. In chapter 15 more will be explained about aromatisation of anabolic steroids.