Dr. Ron’s Research Review – October 10, 2012

This week’s research review focuses on Magnesium and Testosterone.

Supplementation with magnesium increases free and total testosterone values in sedentary and in athletes. The increases are higher in those who exercise than in sedentary individuals. Group 1-sedentary controls supplemented with 10 mg magnesium per kilogram body weight. Group 2-tae kwon do athletes practicing 90-120 min/day supplemented with 10 mg magnesium per kilogram body weight. Group 3-tae kwon do athletes practicing 90-120 min/day receiving no magnesium supplements. The free plasma testosterone levels increased at exhaustion before and after supplementation compared to resting levels. Exercise also increased testosterone levels relative to sedentary subjects. Similar increases were observed for total testosterone. (Cinar, Polat et al. 2011)

In a cohort of older men, magnesium levels are strongly and independently associated with the anabolic hormones testosterone and IGF-1. (Maggio, Ceda et al. 2011)

In the biological Magnesium (2+) concentration domain, it was clearly demonstrated that there was an uncompetitive inhibition of Magnesium (2+) on testosterone-SHBG binding which led an enhancement of bioavailable testosterone. (Excoffon, Guillaume et al. 2009)

The Mg2+ concentration in the young men was directly and significantly related to the progesterone level, and the Ca2+/Mg2+ ratio was inversely related to the progesterone level. (Muneyyirci-Delale, Dalloul et al. 1999)

Dr. Ron


Articles

Effects of magnesium supplementation on testosterone levels of athletes and sedentary subjects at rest and after exhaustion

            (Cinar, Polat et al. 2011) Download

This study was performed to assess how 4 weeks of magnesium supplementation and exercise affect the free and total plasma testosterone levels of sportsmen practicing tae kwon do and sedentary controls at rest and after exhaustion. The testosterone levels were determined at four different periods: resting before supplementation, exhaustion before supplementation, resting after supplementation, and exhaustion after supplementation in three study groups, which are as follows: Group 1-sedentary controls supplemented with 10 mg magnesium per kilogram body weight. Group 2-tae kwon do athletes practicing 90-120 min/day supplemented with 10 mg magnesium per kilogram body weight. Group 3-tae kwon do athletes practicing 90-120 min/day receiving no magnesium supplements. The free plasma testosterone levels increased at exhaustion before and after supplementation compared to resting levels. Exercise also increased testosterone levels relative to sedentary subjects. Similar increases were observed for total testosterone. Our results show that supplementation with magnesium increases free and total testosterone values in sedentary and in athletes. The increases are higher in those who exercise than in sedentary individuals.

Magnesium effect on testosterone-SHBG association studied by a novel molecular chromatography approach

            (Excoffon, Guillaume et al. 2009) Download

A biochromatographic approach is developed to measure for the first time thermodynamic data and magnesium (Mg(2+)) effect for the binding of testosterone (TT) to sex hormone-binding globulin (SHBG) in a wide temperature range. For this, the SHBG was immobilized on a chromatographic support. It was established that this novel SHBG column was stable during an extended period of time. The affinity of TT to SHBG is high and changes slightly with the Mg(2+) concentration because the number of Mg(2+) linked to binding is low. The determination of the testosterone retention with the steroid hormone at different Mg(2+) concentrations and temperatures demonstrated that the Mg(2+) binding heat effect associated with this Mg(2+) release or uptake during this binding was in magnitude around 17kJ/mol corresponding to the model describing the electrostatic attraction that occurs between the negatively charged non specific areas of SHBG and the positively charged of magnesium. At all the magnesium concentrations studied, the DeltaH values were negative due to van der Waals interactions and hydrogen bonding which are engaged at the complex interface confirming strong TT-SHBG hydrogen bond networks. As well, the DeltaS values were all positive due to hydrophobic forces in the testosterone-SHBG complex formation. In addition our results suggest that adaptive conformational transitions contribute to the specific testosterone-SHBG complex formation. As well, in the biological Mg(2+) concentration domain, it was clearly demonstrated that there was an uncompetitive inhibition of Mg(2+) on TT-SHBG binding which led an enhancement of bioavailable TT. Our work indicated that our biochromatographic approach could soon become very attractive for study other SHBG-steroid (or phytoestrogen) binding.

Magnesium and anabolic hormones in older men

         (Maggio, Ceda et al. 2011) Download

Optimal nutritional and hormonal statuses are determinants of successful ageing. The age associated decline in anabolic hormones such as testosterone and insulin-like growth factor 1 (IGF-1) is a strong predictor of metabolic syndrome, diabetes and mortality in older men. Studies have shown that magnesium intake affects the secretion of total IGF-1 and increase testosterone bioactivity. This observation suggests that magnesium can be a modulator of the anabolic/catabolic equilibrium disrupted in the elderly people. However, the relationship between magnesium and anabolic hormones in men has not been investigated. We evaluated 399 >/=65-year-old men of CHIANTI in a study population representative of two municipalities of Tuscany (Italy) with complete data on testosterone, total IGF-1, sex hormone binding globulin (SHBG), dehydroepiandrosterone sulphate (DHEAS) and serum magnesium levels. Linear regression models were used to test the relationship between magnesium and testosterone and IGF-1. Mean age of the population was 74.18 +/- 6.43 (years +/- SD, age range 65.2-92.4). After adjusting for age, magnesium was positively associated with total testosterone (beta +/- SE, 34.9 +/- 10.3; p = 0.001) and with total IGF-1 (beta +/- SE, 15.9 +/- 4.8; p = 0.001). After further adjustment for body mass index (BMI), log (IL-6), log (DHEAS), log (SHBG), log (insulin), total IGF-1, grip strength, Parkinson's disease and chronic heart failure, the relationship between magnesium and total testosterone remained strong and highly significant (beta +/- SE, 48.72 +/- 12.61; p = 0.001). In the multivariate analysis adjusted for age, BMI, log (IL-6), liver function, energy intake, log (insulin), log (DHEAS), selenium, magnesium levels were also still significantly associated with IGF-1 (beta +/- SE, 16.43 +/- 4.90; p = 0.001) and remained significant after adjusting for total testosterone (beta +/- SE, 14.4 +/- 4.9; p = 0.01). In a cohort of older men, magnesium levels are strongly and independently associated with the anabolic hormones testosterone and IGF-1.


Serum ionized magnesium and calcium and sex hormones in healthy young men: importance of serum progesterone level

            (Muneyyirci-Delale, Dalloul et al. 1999) Download

OBJECTIVE: To determine the serum concentrations of the sex hormones with respect to the concentrations of the biologically active fractions of magnesium (Mg) and calcium (Ca) in healthy young men and to compare them with those in young and older women. DESIGN: Controlled clinical study. SETTING: An academic research environment. PATIENT(S): Twenty-five healthy young male volunteers. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Concentrations of the sex steroid hormones testosterone, estrogen, and progesterone, and levels of ionized Ca (Ca2+) and Mg (Mg2+) were measured in the serum of healthy young men. These levels were compared with those in young women at different phases of the menstrual cycle and with those in older women. RESULT(S): The Mg2+ and total Mg concentrations in young men were not different from those during the follicular phase in young women or from the mean concentrations in menopausal women. The Ca2+ levels in young men were similar to the levels in young women during the follicular phase but significantly lower than the levels in older women. The Mg2+ concentration in the young men was directly and significantly related to the progesterone level, and the Ca2+/Mg2+ ratio was inversely related to the progesterone level. CONCLUSION(S): Progesterone may be a more important steroid hormone in men than previously believed.

References

Cinar, V., Y. Polat, et al. (2011). "Effects of magnesium supplementation on testosterone levels of athletes and sedentary subjects at rest and after exhaustion." Biol Trace Elem Res 140(1): 18-23.

Excoffon, L., Y. C. Guillaume, et al. (2009). "Magnesium effect on testosterone-SHBG association studied by a novel molecular chromatography approach." J Pharm Biomed Anal 49(2): 175-80.

Maggio, M., G. P. Ceda, et al. (2011). "Magnesium and anabolic hormones in older men." Int J Androl 34(6 Pt 2): e594-600.

Muneyyirci-Delale, O., M. Dalloul, et al. (1999). "Serum ionized magnesium and calcium and sex hormones in healthy young men: importance of serum progesterone level." Fertil Steril 72(5): 817-22.