View attachment 532
Statin Drugs Markedly Inhibit Testosterone Production by Rat Leydig Cells in Vitro: Implications for Men
Reproductive Toxicology
Available online 22 January 2014
Highlights
•Statins cause significant reductions in LH-stimulated testosterone production by rat Leydig cells; possible human relevance.
•Statin induced inhibition in testosterone production was bypassed by providing pregnenolone or progesterone.
•Bypassing the site of action with pregnenolone resulted in greater LH stimulated testosterone production than progesterone.
•LH responsiveness of Leydig cells was only maintained when progesterone was used to bypass the site of action.
Abstract
Statin drugs lower blood cholesterol by inhibiting hepatic 3-hydroxy-3-methylglutaryl-Coenzyme-A reductase. Statins are known to inhibit sterol production in the testis, but effect of statins on testosterone production has not been studied critically in vitro and clinical data are controversial. We measured 18-hour testosterone production in vitro, using highly purified rat Leydig cells exposed to atorvastatin, mevastatin, or simvastatin and also determined if statin-induced inhibition of testosterone production could be bypassed with substrate distal to cholesterol. Statins had no effect on testosterone production during culture without LH. However, with 10 ng/mL LH, testosterone production was ≥12-fold higher and markedly inhibited (-40%) by ≥0.3 μM statin. Leydig cells provided sub-saturating pregnenolone or progesterone to bypass the site of statin action, maintained LH-stimulated testosterone production at or above amounts observed with LH stimulation and no statin. Pregnenolone resulted in greater testosterone production, but LH responsiveness was lost. With progesterone, LH responsiveness was maintained.
The paper above is Klinefelter, G.R.; Laskey, J.W.; Amann, R.P. Statin drugs markedly inhibit testosterone production by rat Leydig cells in vitro: implications for men. Reprod Toxicol 2014, 45, 52-58, doi:10.1016/j.reprotox.2013.12.010
There are other peer-reviewed papers involving humans:
Stanworth, R.D.; Kapoor, D.; Channer, K.S.; Jones, T.H. Statin therapy is associated with lower total but not bioavailable or free testosterone in men with type 2 diabetes. Diabetes Care 2009, 32, 541-546, doi:10.2337/dc08-1183.
Corona, G.; Boddi, V.; Balercia, G.; Rastrelli, G.; De Vita, G.; Sforza, A.; Forti, G.; Mannucci, E.; Maggi, M. The effect of statin therapy on testosterone levels in subjects consulting for erectile dysfunction. J Sex Med 2010, 7, 1547-1556, doi:10.1111/j.1743-6109.2009.01698.x
In the Stanworth article, the abstract is shown below:
OBJECTIVE: There is a high prevalence of hypogonadism in men with type 2 diabetes. This will lead to an increase in assessments of hypogonadism. Statins could potentially decrease testosterone levels by reducing the availability of cholesterol for androgen synthesis. We compared testosterone levels and hypogonadal symptoms with statin use in a cross-sectional study of 355 men with type 2 diabetes. RESEARCH DESIGN AND METHODS: Total testosterone, sex hormone-binding globulin (SHBG), and estradiol were measured by an enzyme-linked immunosorbent assay. Bioavailable testosterone was measured by the modified ammonium sulfate precipitation method. Free testosterone was calculated using Vermeulen's formula. Symptoms of hypogonadism were assessed using the Androgen Deficiency in the Aging Male questionnaire. RESULTS: Statins were associated with lower total testosterone (11.9 vs. 13.4 nmol/l, P = 0.006) and a trend toward lower SHBG (29.4 vs. 35.3 nmol/l, P = 0.034) compared with no treatment.
11.9x 28.85= 343 ng/dl
13.4 x 28.85= 387 ng/dl
My comment inserted: This may be significant but doubt it has clinical relevance.
Bioavailable testosterone, free testosterone, estradiol, and hypogonadal symptoms were not affected. Subanalysis showed that atorvastatin was associated with reduced total testosterone (11.4 vs. 13.4 nmol/l, P = 0.006) and a trend toward reduced SHBG (27.6 vs. 35.3 nmol/l, P = 0.022) compared with no treatment, and there was an apparent dose-response effect with the lowest levels of total testosterone seen in men treated with >or=20 mg atorvastatin (9.6 nmol/l, P = 0.017). Simvastatin use was not associated with significant reductions in testosterone or SHBG levels. CONCLUSIONS: Assessing androgen status using total testosterone in men with type 2 diabetes treated with statins, particularly atorvastatin, may potentially lead to diagnostic error. Levels of bioavailable testosterone or free testosterone are recommended for the assessment of hypogonadism in this group if total testosterone levels are borderline.
I showed the calculations above and do not think these results would be noticeable by men on statins. The Stanworth article is attached.