Sex Hormone Binding Globulin [SHBG]

[Stinefeller]

Re: Calling out the low SHBG guys

Tamoxifen (or SERM) will be worthless long-term. It will raise the TT, but not be an effective solution. What are the thyroid studies?

Gf and I have plans to get kids in a few years. I don't want to compromise my fertility, After the kids I'll go on test injections.

Endo warned me that tamoxifen wont bring levels up above maybe 400 but its an improvement at least. Plus, raise in shbg might reverse the balding. I am 29, 1,90 m and 87 kg. My condition is congenital, I can tell from old pictures. I have researched every male sex disorder but none match.

Thyroid is normal. T3 was 1,2 or something. Don't remember the exact number. He specifically mentioned my thyroid was normal. Free t3 and t4 were normal as well.

 

[hardrlz]

Re: Calling out the low SHBG guys

In several boards i saw that increased fiber intake also highers SHBG but i cant find any study on that. Can someone comment on that ? Also some say that smoking highers SHBG as well and i found this study ttp://212.250.180.69/cs/100/0661/1000661.pdf that says that smokers have higher SHBG. Guess i am starting cigarettes from tmrw

 

[hardrlz]

Re: Calling out the low SHBG guys

Is it true that the rise in SHBG you get from green tea and beta sitosterol is not an actual rise since they produce some compound that binds with SHBG and thus the body responds by producing more SHBG which equals the binded one from the green tea and beta sitosterol and does this mean they are not effective at rising SHBG needed for testosterone ? ( i read that in another forum )

 

[Michael Scally MD]

Re: Calling out the low SHBG guys

Longcope C, Feldman HA, McKinlay JB, Araujo AB. Diet and Sex Hormone-Binding Globulin. Journal of Clinical Endocrinology & Metabolism 2000;85(1):293-6. Diet and Sex Hormone-Binding Globulin

The serum concentration of sex hormone-binding globulin (SHBG) is inversely related to weight and in animal studies is inversely related to protein intake. As SHBG can affect the biological activity of testosterone and estradiol, we wished to determine the role of protein intake on SHBG levels in men. Using data from the Massachusetts Male Aging Study we examined cross-sectional relationships between dietary components and SHBG levels in 1552 men (aged 40-70 yr) for whom these factors were known. Analyzed by multiple regression, controlling for testosterone and estradiol levels, age (P < 0.001) and fiber intake (P = 0.02) were positively correlated to SHBG concentration, whereas body mass index (P < 0.001) and protein intake (P < 0.03) were negatively correlated to SHBG concentration. The intakes of calories, fat (animal or vegetable), and carbohydrate were not related to SHBG concentration. We conclude that age and body mass index are major determinants of SHBG concentrations in older men, and fiber and protein intake are also significant contributors to SHBG levels, but total caloric intake and the intake of carbohydrate or fat are not significant. Thus, diets low in protein in elderly men may lead to elevated SHBG levels and decreased testosterone bioactivity. The decrease in bioavailable testosterone can then result in declines in sexual function and muscle and red cell mass, and contribute to the loss of bone density.

 

[Blazerone]

Re: Calling out the low SHBG guys

I've read that many men young and old struggle with TRT if they have low SHBG, me included. I've tried cypionate, enanthate, trouches and androgel and none of them worked except the androgel but just for a couple months. I finally tried propionate and I have felt the best I have in years!

 

[dogheat]

Re: Calling out the low SHBG guys

my shbg is usually high but just still in range. I was taking DHEA for a couple of months and my shbg increased to almost 70.

 

[hardrlz]

Re: Calling out the low SHBG guys

I think DHEA actually reduces SHBG.

 

[CensoredBoardsSuck]

Re: Calling out the low SHBG guys

I am jumping in here without reading the posts, but only the thread title. I find the low SHBG and hypogonadal symptoms to be interesting. And, possible quite informative if ever researched. It goes against the Free Hormone Hypothesis, which needs more research itself. I find it difficult to believe that the sole purpose of SHBG is to bind testosterone.

J Endocrinol Invest. 1999 Mar;22(3):223-34.
Sex hormone-binding globulin: not only a transport protein. What news is around the corner?
Sex hormone-binding globulin: not only a... [J Endocrinol Invest. 1999] - PubMed - NCBI
Fortunati N.

Abstract

The plasma Sex Hormone-Binding Globulin (SHBG) transports androgens and estradiol in the blood and regulates their bioavailable fraction and access to target cells. The recent advances in the knowledge of its structure and gene expression, and notabily the demonstration of a specific receptor (SHBG-R) located on membranes of sex steroid responsive cells, gave support to the thesis that SHBG has much more sophisticated functions at cell site. In particular, the receptor-mediated action of SHBG, which uses as a second messenger cAMP, has been linked to the effects of androgens and estradiol. It is conceivable that the SHBG/SHBG-R system works as an additional control mechanism which inhibits or amplifies the effects of DHT and estradiol in cells. In the prostate, it has been suggested that the estradiol-activated SHBG/SHBG-R complex cross-talks with the androgen receptor, and is able to activate AR even in the absence of DHT. Of great interest, for its potential clinical applications, is the observation that in estrogen-dependent breast cancer SHBG, through SHBG-R, cAMP and PKA, specifically inhibits the estradiol-induction of cell proliferation. This anti-proliferative, anti-estrogenic effect of human SHBG has not only increased and continues to increase our understanding of the molecular mechanisms involved in the biology of breast cancer, but could also be exploited as a future therapeutic strategy in the managing of estrogen-dependent tumours.


Horm Metab Res. 2001 Jan;33(1):7-9.
Evidence of sex hormone binding globulin binding sites in the medial preoptic area and hypothalamus.
Evidence of sex hormone binding globulin bind... [Horm Metab Res. 2001] - PubMed - NCBI
Caldwell JD.

Abstract

We have demonstrated a high density of both radiolabeled progesterone and estradiol conjugated to bovine serum albumin binding sites in the medial preoptic area and hypothalamus. Infusions of sex hormone binding globulin into the medial preoptic area of rats increased their female sexual receptivity similarly to the effect of estradiol conjugated to bovine serum albumin, suggesting sex hormone binding globulin acts at binding sites for estradiol conjugated to bovine serum albumin. In this study sex hormone binding globulin was used to displace radiolabeled progesterone conjugated to bovine serum albumin from plasma membrane fractions from the medial preoptic area-anterior hypothalamus and medial basal hypothalamus of ovariectomized rats injected with either 5 microg estradiol benzoate or sesame oil vehicle. We found that sex hormone binding displaced radiolabeled progesterone conjugated to bovine serum albumin in both areas and that in vivo estradiol treatment greatly increased the relative displacement by sex hormone binding globulin in the medial preoptic area-anterior hypothalamus. We interpret these data as indicating the presence of sex hormone binding globulin receptors in brain plasma membranes and further suggest that endogenous steroid conditions may alter these receptors.

 

[hardrlz]

Re: Calling out the low SHBG guys

Is it possible that although my fasting glucose test turned out to be normal, the low shbg is predicting a future onset of insuline resistance ? Also i have had some stomach problems from a long time with symptoms like irritable bowel syndrome, but i am thinking that its possible that my pancreas has some kind of dysfunction, which could be somehow related with my insuline production and low SHBG, does this make sense ?

 

[idmd]

Re: Calling out the low SHBG guys

Is it possible that although my fasting glucose test turned out to be normal, the low shbg is predicting a future onset of insuline resistance ? Also i have had some stomach problems from a long time with symptoms like irritable bowel syndrome, but i am thinking that its possible that my pancreas has some kind of dysfunction, which could be somehow related with my insuline production and low SHBG, does this make sense ?

While I've read low SHBG can be a sign of IR I think many other things control SHBG levels and I don't know low SHBG has ANY predictive value as far as future IR. There are other way to assess IR.

 

[hardrlz]

Re: Calling out the low SHBG guys

I found these two studies Association between low concentration of serum sex hormone binding globulin and insulin resistance is independent of adiposity, but may be attributable to fasting insulin concentration and Sex Hormone–Binding Globulin Levels Predict Insulin Sensitivity, Disposition Index, and Cardiovascular Risk During Puberty as well as two other that i can not find right now suggesting that it is possible that low SHBG is a predictor of future insulin resistance. However, i am not sure how to interpret that as i am aiming at increasing my SHBG and currently i am not insulin resistant.

 

[Pericles]

Re: Calling out the low SHBG guys

Didn't read all the posts, but theoretically, low SHBG is a good thing. High SHBG means that more testosterone is gobbled up. So, you could have, say, a solid 550 test, but only a fraction is usable free T.

True, it is very possible that SHBG has other functions, but reducing receptivity to total T is the main function.

 

[hardrlz]

Re: Calling out the low SHBG guys

Theoretically it is , but unfortunately practically i see more and more people like me with low shbg prior to therapy fail to see any improvements from testosterone

 

[hardrlz]

Re: Calling out the low SHBG guys

http://www.dannyroddy.com/main/2010/9/3/everything-you-know-about-hair-loss-is-wrong.html i found this article connecting low shbg with fatty liver disease. Has someone heard the same theory ?

 

[idmd]

Re: Calling out the low SHBG guys

http://www.dannyroddy.com/main/2010/9/3/everything-you-know-about-hair-loss-is-wrong.html i found this article connecting low shbg with fatty liver disease. Has someone heard the same theory ?

Most people who are IR will also have non-alcoholic fatty liver. He's basically saying the same thing a different way. Nothing new stated here.

 

[hardrlz]

Re: Calling out the low SHBG guys

Is it possible that fatty liver can occur first , then low SHBG and then IR or it all starts from IR ?

 

[idmd]

Re: Calling out the low SHBG guys

Is it possible that fatty liver can occur first , then low SHBG and then IR or it all starts from IR ?

I'm not sure a cause and effect relationship has been worked out but you can bet the risk factors for both IR and fatty liver are the same. Ex. Excessive caloric intake with increased visceral fat causes chronic hyperinsulinemia and excess FFA being dumped into the portal vein which in turn lead to IR and fatty liver. I've read some things suggesting IR happens first but clinically I do not think this is important. If you you remove the excess caloric intake and visceral fat both get better.

FWIW there are other causes of non-alcoholic fatty liver too like medications and some people are genetically more predisposed but you are quite capable of looking that up.

 

[Dr JIM]

Re: Calling out the low SHBG guys

I've got to agree with DOC here the notion a low SHBG is an etiologic basis for hypogonadism is just NOT based in the literature absent other metabolic derangements.

Moreover SHBGs ability to participate in the minute to minute regulation of serum androgen levels are very limited UNLESS a considerable decline occurs.

Lastly if SHBGs only function was a "carrier molecule" then why has the globular protein been found within cells UNLIKE albumin.

 

[James23]

Re: Calling out the low SHBG guys

As it has been emphasized in this thread, low SHBG appears to be the single highest correlation among men that are a) young b) experience sexual dysfunction c) have low testosterone and ultimately d) feel absolutely nothing when the low T is corrected.

There is a very large caveat that must be understood. We are not talking about men who have had normal or high SHBG and who have driven it low with TRT use. When we talk about the "low SHBG" condition, it is limited to those males who have had SHBG that NEVER increases to within normals even in light of changing hormonal environment. In other words, SHBG production is impaired in these males.

There was a discussion in a separate thread about a supplement protocol including green tea, beta sitosterol and other compounds. This will not work.

These compounds (EGCG in green tea; ligands in flax seed/beta sitosterol) simply bind to SHBG. In healthy men, this will cause the body to increase SHBG production to match the loss. However, in "low SHBG" men, this will serve only to further decrease SHBG. The SHBG increasing effect of caffeine excited researchers, but you must understand that this increase was demonstrated in post-menopausal women with normal SHBG (no impairment) and was a whopping 2 nmol/L (insignificant.)

SHBG is very highly correlated with insulin resistance. I just completed a 2 hour insulin challenge and discovered that I experience reactive hypoglycemia in response to 75g fasting glucose, even though my insulin never peaks 40 uIU/mL.

Could the low SHBG men please report their DHEA-S, TSH and RT3? It is important to rule out obvious causes.

 

[Dr JIM]

Re: Calling out the low SHBG guys

The presumption that LOW SHBG is the etiologic basis for these complaints is absolute rubbish.

Is there an association between low SHBG and SD?

NOT one that is literature based OR which is consistent with known medical practice.

James you have been arguing there IS a cause and effect relationship between LOW SHBG and SD ever since you entered the halls of Meso and have even told mates with this "condition" they "need to raise their SHBG" as treatmet, WITHOUT any evidence to support this form of "therapy".

Each and every time you leave when asked to prove your point based on the literature and shortly thereafter I'm met with silence.

WELL NOW YOU HAVE ANOTHER CHANCE !!!

These individuals complain of SD yet sexual dysfunction is more often a multi-factorial disorder and as such has many variables which contribute to its presentation simultaneously or in combination.

Consequently it's its fool hearty for you to assume an couched layman whom has never evaluated either of the mates is more adept at making a more accurate diagnosis (which is contradictory to known SHBG function) than those whom have done so.

Jim