Telomeres undergo attrition with each cell division, and telomere length is associated with age-related diseases and mortality in the elderly. Estrogen can influence the attrition of telomeres by diverse mechanisms. This is a retrospective case control study that investigated the influence of long-term hormone therapy (HT) on telomere length in postmenopausal women. We recruited 130 postmenopausal women from 55 to 69 years of age for this study, and divided them into two groups. The first group included 65 women who had been on estrogen and progesterone therapy for more than five years (HT group). The other group was composed of 65 women matched in age to the HT group who had never had HT (non-HT group). The relative ratios of telomere length of study subjects to a reference DNA from a healthy young female were measured using quantitative PCR. Plasma levels of lipid profiles, total antioxidant status (TAS), C-reactive proteins (CRP), fasting glucose levels, and estradiol levels were measured. Age at menopause, vitamin use, and exercise, alcohol, and cigarette smoking histories were also assessed in a questionnaire. Mean duration (± SD) of HT was 8.4 ± 2.3 years. Prevalence of vitamin use and regular exercise were higher in the HT group than in the non-HT group (p<0.01). Relative telomere length ratios in the HT group were significantly greater than those in the non-HT group (p<0.01). HT was significantly correlated with the relative telomere length ratio in multivariate analysis when potential confounding variables were controlled for (p<0.05). In conclusion, telomere lengths were longer in postmenopausal women who had a history of long-term HT than in postmenopausal women without HT. Long-term HT in postmenopausal women may alleviate telomere attrition.

LEE, JI-WON, JEE-AEE IM, HYE-REE LEE, JAE-YONG SHIM, BYUNG-S. YOUN, AND DUK-CHUL LEE.Visceral adiposity is associated with serum retinol binding protein-4 levels in healthy women. Obesity. 2007;15: 2225-2232. Objective: Retinol binding protein-4 (RBP4) has been reported to impair insulin sensitivity throughout the body. We investigated the relationship between serum RBP4 levels and adiposity indices as well as metabolic risk variables. Research Methods and Procedure: We recruited a total of 102 healthy women 21 to 67 years old. We assessed body composition by computed tomography and divided the study population into four groups based on body weight and visceral fat area (non-obese without visceral adiposity, nonobese with visceral adiposity, obese without visceral adiposity, and obese with visceral adiposity). Serum RBP4 levels were measured by radioimmunoassay. Results: Despite similar levels of total body fat, non-obese women had lower systolic blood pressure, total cholesterol, triglyceride (TG), low-density lipoprotein (LDL)-cholesterol levels, insulin resistance indices, and RBP4 levels than non-obese women with visceral adiposity and had higher high-density lipoprotein-cholesterol levels. Similarly, obese women without visceral adiposity had lower blood pressure, total cholesterol, TG levels, insulin resistance indices, and RBP4 levels than obese women with visceral adiposity. In addition, despite having increased body fat, obese women without visceral adiposity had lower TGs, insulin resistance indices, and serum RBP4 levels than non-obese women with visceral adiposity. By step-wise multiple regression analysis, visceral fat areas and LDL-cholesterol levels independently affected RBP4 levels. Discussion: We determined that serum RBP4 levels are independently associated with visceral fat and LDL-cholesterol levels. These results suggest that, irrespective of body weight, visceral obesity is an independent predictor of serum RBP4 levels, and RBP4 may represent a link between visceral obesity and cardiovascular disease.

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