Effects of estrone sulfate alone or with medroxyprogesterone acetate on serum lipoprotein levels in postmenopausal women

Estrogens and the regulation of glucose metabolism

The main estrogens: estradiol, estrone, and their acyl-esters have been studied essentially related to their classical estrogenic and pharmacologic functions. However, their main effect in the body is probably the sustained control of core energy metabolism. Estrogen nuclear and membrane receptors show an extraordinary flexibility in the modulation of metabolic responses, and largely explain gender and age differences in energy metabolism: part of these mechanisms is already sufficiently known to justify both. With regard to energy, the estrogen molecular species act essentially through four key functions: (1) Facilitation of insulin secretion and control of glucose availability; (2) Modulation of energy partition, favoring the use of lipid as the main energy substrate when more available than carbohydrates; (3) Functional protection through antioxidant mechanisms; and (4) Central effects (largely through neural modulation) on whole body energy management. Analyzing the different actions of estrone, estradiol and their acyl esters, a tentative classification based on structure/effects has been postulated. Either separately or as a group, estrogens provide a comprehensive explanation that not all their quite diverse actions are related solely to specific molecules. As a group, they constitute a powerful synergic action complex. In consequence, estrogens may be considered wardens of energy homeostasis.

Effect of hormone therapy and calcitriol on serum lipid profile in postmenopausal older women: association with estrogen receptor-α genotypes

OBJECTIVE

The aim of this study was to examine the effect of conjugated equine estrogens alone (ET), conjugated equine estrogens + medroxyprogesterone (EPT), calcitriol alone, calcitriol + EPT/ET, or placebo on serum lipid profile and analyze the interaction with estrogen receptor-α gene single nucleotide polymorphisms (ESR-α SNPs) on the response to therapy.

METHODS

A total of 489 postmenopausal women older than 65 years were enrolled into a 3-year double-blind, placebo-controlled clinical trial.

RESULTS

In both intent-to-treat and complier (>80% adherent) analysis, there was a significant increase in serum high-density lipoproteins and a significant decrease in serum low-density lipoproteins (LDLs) and the LDL/high-density lipoprotein ratio in all hormone treatment groups compared with placebo (P < 0.05). However, serum triglycerides and very low-density lipoproteins increased in the EPT and ET + calcitriol groups versus placebo (P < 0.05). ESR-α SNPs PvuII and XbaI seemed to have a significant effect on the response to treatment. Genotypes containing the p allele showed a significantly greater decrease in serum cholesterol and very low-density lipoprotein than those having the P allele in the ET + calcitriol group (P < 0.05), and those with the x allele had a significantly greater decrease in serum cholesterol in the hormone therapy + calcitriol group at the end of 3 years versus the X allele, and a greater decrease in serum LDL in alleles x versus the X in the ET + calcitriol group (P < 0.05).

CONCLUSIONS

ET with or without progesterone had a favorable effect on lipid profile in postmenopausal older women, and this was dependent on estrogen receptor SNPs--PvuII and XbaI. However, this interaction with ESR-α SNPs needs to be confirmed in larger studies.