ORIGINAL ARTICLE Effect of Dehydroepiandrosterone and Testosterone Supplementation on Systemic Lipolysis Ana E. Espinosa De Ycaza, Robert A. Rizza, K. Sreekumaran Nair, and Michael D. Jensen Division of Endocrinology, Endocrine Research Unit, Mayo Clinic, Rochester, Minnesota 55905 Downloaded from https://academic.oup.com/jcem/article/101/4/1719/2804555 by guest on 24 September 2021 Context: Dehydroepiandrosterone (DHEA) and T hormones are advertised as antiaging, antiobe- sity products. However, the evidence that these hormones have beneficial effects on adipose tissue metabolism is limited. Objective: The objective of the study was to determine the effect of DHEA and T supplementation on systemic lipolysis during a mixed-meal tolerance test (MMTT) and an iv glucose tolerance test (IVGTT). Design: This was a 2-year randomized, double-blind, placebo-controlled trial. Setting: The study was conducted at a general clinical research center. Participants: Sixty elderly women with low DHEA concentrations and 92 elderly men with low DHEA and bioavailable T concentrations participated in the study. Interventions: Elderly women received 50 mg DHEA (n ϭ 30) or placebo (n ϭ 30). Elderly men received 75 mg DHEA (n ϭ 30),5mgT(nϭ 30), or placebo (n ϭ 32). Main Outcome Measures: In vivo measures of systemic lipolysis (palmitate rate of appearance) during a MMTT or IVGTT. Results: At baseline there was no difference in insulin suppression of lipolysis measured during MMTT and IVGTT between the treatment groups and placebo. For both sexes, a univariate analysis showed no difference in changes in systemic lipolysis during the MMTT or IVGTT in the DHEA group and T group when compared with placebo. There was no change in the results after adjusting for the resting energy expenditure, except for a small, but significant (P ϭ .03) lowering of MMTT nadir palmitate rate of appearance in women who received DHEA. Conclusion: In elderly individuals with concentrations of DHEA (men and women) or T (men) below the normal range for young adults, supplementation of these hormones has no effect on insulin suppression of systemic lipolysis. (J Clin Endocrinol Metab 101: 1719–1728, 2016) he production of the androgens dehydroepiandros- ever, association does not mean causality. Hence, replace- T terone (DHEA) and T declines with aging (1–3). ment of androgens in elderly men and women who have Whether this decline has detrimental consequences to plasma concentrations of DHEA and T below the normal overall health is unknown, but DHEA and T are being range for young adults may not improve fat distribution or used to improve muscle mass/strength and reduce body adipose function. fat. There are well-documented, sex-specific associations The studies that tested the effects of androgens on body between androgen levels and body fat distribution; how- composition, adipose metabolism, adipocyte differentia- ISSN Print 0021-972X ISSN Online 1945-7197 Abbreviations: AT, adipose tissue; AUC, area under the curve; CV, coefficient of variation; Printed in USA DHEA, dehydroepiandrosterone; DHEAS, sulfated dehydroepiandrosterone; FFA, free fatty Copyright © 2016 by the Endocrine Society acid; IVGTT, iv glucose tolerance test; MMTT, mixed-meal tolerance test; Ra, rate of ap- Received November 24, 2015. Accepted February 12, 2016. pearance; REE, resting energy expenditure. First Published Online February 17, 2016 doi: 10.1210/jc.2015-4062 J Clin Endocrinol Metab, April 2016, 101(4):1719–1728 press.endocrine.org/journal/jcem 1719 1720 Espinosa De Ycaza et al Effect of DHEA and Testosterone on Lipolysis J Clin Endocrinol Metab, April 2016, 101(4):1719–1728 tion, and lipolysis have given inconsistent results (4–12). and an iv insulin profile. They first underwent an insulin-mod- Several human studies report that DHEA and T stimulate ified IVGTT followed by a second inpatient visit for MMTT. We 3 lipolysis (8, 12, 13). used a continuous infusion of [9,10- H]palmitate (0.3 Ci/min) during both IVGTT and MMTT to assess palmitate kinetics. The We conducted a randomized, double-blind, placebo- details of the protocol used for IVGTT and MMTT have been controlled trial to evaluate the effects on body composi- published (17). The medications (T patch, DHEA, and placebo) tion, quality of life, glucose, and fat metabolism of DHEA were continued during the inpatient visits and were given each replacement in elderly men and women and T replacement morning. Of the initially randomized volunteers, eight elderly in elderly men, with low concentrations of these hor- women and nine elderly men did not complete the studies of mones. We found no significant, clinically relevant effects palmitate kinetics. During these studies palmitate concentration and specific ac- on body composition, quality of life, and insulin sensitivity tivity were measured at baseline (before the meal or iv insulin) after 24 months of supplementation with DHEA or T (14, and every 30 minutes for 3 hours during the MMTT and at 20, Downloaded from https://academic.oup.com/jcem/article/101/4/1719/2804555 by guest on 24 September 2021 15). The group that received T had an increase in meal 31, 45, 90, and 120 minutes during the IVGTT. Suppression of fatty acid storage in the sc abdominal adipose tissue (AT) lipolysis during either test is reported as the nadir palmitate rate compared with femoral sc AT (16). Although we could not of appearance (Ra) or the area under the curve (AUC) for the detect an effect of DHEA or T on postabsorptive lipolysis palmitate Ra. The AUC for palmitate concentration and AUC for Ra was the AUC for these parameters estimated throughout the (16), we cannot infer the same for postprandial lipolysis. entire duration of the MMTT or IVGTT. Furthermore, the differences in meal fatty acid storage The techniques used for each of the hormone concentration, previously reported (16) could be offset by androgen-in- substrate, and palmitate assays have been previously reported duced changes in insulin suppression of lipolysis in the (16, 17). Nonsteady-state formulas were used to calculate palmi- postprandial state. As part of this 2-year study of DHEA tate Ra for the postprandial and IVGTT studies (18). and T replacement in elderly men and women, we col- The methods used to measure hormone levels are described below. lected data to test the hypotheses that T or DHEA sup- Total T was measured using a competitive chemiluminescent plementation had an effect on systemic lipolysis during a immunoassay on the DxI 800 automated immunoassay system mixed-meal tolerance test (MMTT) or an insulin-modi- (Beckman Instruments). Intraassay coefficients of variation fied iv glucose tolerance test (IVGTT). (CVs) are 6.5% at 69 ng/dL and 3.3% at 862 ng/dL. Interassay CVs are 7.4% at 116 ng/dL, 8.6% at 407 ng/dL, and 4.0% at 761 ng/dL. Bioavailable T was measured by the differential precipitation Materials and Methods of SHBG by ammonium sulfate after the equilibration of the serum sample with tracer amounts of tritium-labeled T. The re- Herein we report pre- and postintervention postprandial and sults are expressed as the percentage of T free or albumin bound insulin-suppressed free fatty acid (FFA) data from 135 elderly (not precipitated with SHBG) compared with an albumin stan- adults (Ͼ60 y) who participated in a published trial (14) assess- dard. The product of this percentage and the total T measure- ing the effect of 2 years of placebo vs supplementation with ment is the total bioavailable T. Intraassay CV was 5.4 at 14.1% DHEA or T on body composition, glucose metabolism, and bone of bioavailable T. Interassay CVs are 7.5 at 28.4%, 4.9 at 41.9%, density. This study was approved by the Mayo Institutional Re- and 4.9 at 50.8% of bioavailable T. view Board. Participants providing informed consent included SHBG was measured by a solid phase, two-site chemilumi- 60 elderly women with sulfated DHEA levels less than 0.95 nescent assay on the Siemens Immulite 2000 automated immu- g/mL and 92 elderly men with bioavailable T levels less than noassay system (Siemens Healthcare Diagnostics). Intraassay 103 ng/dL and sulfated DHEA levels less than 1.57 g/mL. Bio- CVs are 2.7% and 3.1% at 5.5 and 95.9 nmol/L, respectively. available T levels of less than 103 ng/dL correspond to levels less Interassay CVs are 4.0% at 5.4 and 5.9% at 74 nmol/L. than 2 SD of the mean, normal concentration for young men, and DHEA sulfate was measured by a solid-phase, competitive DHEA levels less than 1.57 g/mL, corresponding to levels less chemiluminescent enzyme immunoassay (EIA) on the Siemens than 1.5 SD of the mean, normal concentration for young men Immulite 2000 automated immunoassay system (Siemens (20–30 y of age). Women were randomly assigned to receive DHEA (n ϭ 30) or Healthcare Diagnostics). The intraassay CVs are 5.7%, 5.7%, placebo (n ϭ 30), and men were randomly assigned to receive 5.7%, and 5.1% at 26.4, 77, 203, and 493 g/dL. The inter- DHEA (n ϭ 30), T (n ϭ 30), or placebo (n ϭ 32) (14). T was given assay CVs are 5.2%, 3.6%, and 5.4% at 80.1, 211, and 515 as a 5-mg patch applied daily and thus resulted in continuous g/dL, respectively. delivery of T to the men. DHEA was taken as tablets each morn- ing, 50 mg for women and 75 mg for men. The FFA flux study Statistical analysis procedures have been previously described in detail (16, 17). Baseline characteristics and descriptive data are presented as Briefly, participants underwent outpatient and inpatient visits at median (interquartile range) for continuous variables and pro- baseline and 24 months after replacement with placebo, DHEA, portion for categorical variables.
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