Martha A. Sánchez-Rodríguez

Serum Leptin Levels and Blood Pressure in the Overweight Elderly

BACKGROUND Leptin is a protein produced by adipocytes that reduces reflex appetite by blocking the Y neuropeptide, thus causing body weight loss. A large percentage of elderly people are reported to exhibit obesity, which may be caused by low leptin serum levels. However, hypertension is a highly prevalent condition in old age. Obesity under these circumstances is an added risk factor due to the presence and severity of hypertension and thus can be related with leptin serum levels. Our objective was to determine the relationship between leptin serum levels and hypertension in obese elderly persons. METHODS A comparative transverse study was done in a random sample of 61 elderly persons-36 obese and 25 non-obese. Their blood pressure and their leptin serum levels by RIA were measured. RESULTS Leptin serum levels showed a statistically significant difference (p <0.05) in elderly obese individuals (12.8 +/- 4.4 microg/L vs. 9.8 +/- 4.2 microg/L). Likewise, 45% of obese elderly individuals and 20% of the non-obese were hypertensive with a predominant elevation of the systolic pressure. CONCLUSIONS The higher serum leptin levels in obese elderly individuals suggests that aging is associated with resistance to leptin and/or to a decrease of receptors for this hormone. The high incidence of hypertension during the aging process is the result of associated obesity (OR = 3.2, CI 0.88-13.14).

Relationship between Metabolic Syndrome Components and Oxidative Stress in Elderly Community-Dwelling Mexicans

Aim: To determine the relationship between metabolic syndrome (MetS) components and oxidative stress (OxS) in elderly community-dwelling Mexicans. Methods: We carried out a comparative cross-sectional study on 113 elderly subjects (≧60 years old); 50 of them did not have MetS and 63 did have MetS (based on Adult Treatment Panel III criteria). We measured total antioxidant status (TAS), plasma lipid peroxidation (LPO), antioxidant activity of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and calculated the SOD/GPx ratio. High blood pressure (HBP) was defined as systolic blood pressure (SBP) ≧140 mm Hg and/or diastolic blood pressure (DBP) ≧90 mm Hg. Results: We found a statistically significant increase in the percentage of cases of severe OxS in elderly subjects with MetS in comparison to healthy elderly (17 vs. 8%, OR: 7.33, 95% CI: 1.38–42.39; p < 0.01). It was observed that subjects with 5 MetS components had a 10-fold higher risk of developing OxS than subjects with 1 component (OR: 11.00, 95% CI: 1.72–115.17; p < 0.01). A positive correlation between SBP and LPO (r = 0.202, p < 0.05), and a negative correlation of SBP and DBP with TAS activity (r = –0.232, p < 0.05; r = –0.211, p < 0.05) were also observed. Conclusion: Our findings suggest that MetS is linked to severe OxS, that the number of metabolic syndrome components is a significant risk factor in the development of OxS, and that HBP is the most important metabolic syndrome component linked to OxS in the elderly.

Undernutrition and oxidative stress as risk factors for high blood pressure in older Mexican adults.

Objective: To determine the relationship between undernutrition and oxidative stress as risk factors for high blood pressure (HBP) in older Mexican adults. We carried out a case-control study in a convenience sample of 62 older adults, 60–80 years of age; 32 without HBP (mean age 75.8 ± 5.1 years) and 30 with HBP (mean age 65.2 ± 6.8 years). Methods: We measured serum lipoperoxide (LPO) levels, antioxidant enzymes, total antioxidant activity and lipid profile; in addition, we evaluated the nutritional status with anthropometric measurements, the Mini Nutritional Assessment and food intake frequency. Data were analyzed with Student t and odds ratio (OR) statistical tests. Results: We observed significantly higher LPO levels in subjects with HBP than in normotensive subjects (0.303 ± 0.10 vs. 0.256 ± 0.06 μmol/l; p < 0.05). With respect to risk factors for HBP, we found an OR of 12.2 (95% CI 1.9–76.4, p < 0.01) in subjects with high LPO levels (≥0.320 μmol/l) and an OR of 5.0 (95% CI 1.1–23.0, p < 0.05) in those with undernutrition. Conclusion: Our findings suggest that high LPO levels and undernutrition are significant risk factors for HBP.

Menopause and Oxidative Stress

In women, postmenopause may be considered the beginning of aging due to a series of changes that are caused by the decline of estrogen levels, some of which involve the skin. It is known that estrogens have an antioxidant activity and function as sex hormone; therefore, a decrease in estrogen levels during the postmenopausal period is one of the factors that control age-related oxidative stress.

Contents Vol. 56, 2010

F. Azizi, Tehran A. Berg, Freiburg F. Branca, Rome R. Brigelius-Flohé, Nuthetal P.C. Calder, Southampton N. Chang, Seoul T. Decsi, Pécs K. Eder, Halle/Saale A. El-Sohemy, Toronto, Ont. H. Goldenberg, Vienna R. Hakkak, Little Rock, Ark. H. Hauner, Munich S. Hercberg, Paris H. Heseker, Paderborn N. Houalla, Beirut A. Kafatos, Heraklion M.-H. Kang, Daejeon E.T. Kennedy, Boston, Mass. M. Krawinkel, Giessen G. Krejs, Graz A.V. Kurpad, Bangalore W. Langhans, Zurich M. Lawrence, Burwood, Vic. D. Li, Hangzhou X. Lin, Shanghai J. Linseisen, Heidelberg J.A. Martinez, Pamplona Y. Naito, Kyoto H.Y. Paik, Seoul M. Panagiotidis, Reno, Nev. J.M. Pettifor, Johannesburg L.A. Réthy, Budapest G. Rimbach, Kiel J. Sabaté, Loma Linda, Calif. W.H.M. Saris, Maastricht L. Serra-Majem, Las Palmas de Gran Canaria A.P. Simopoulos, Washington, D.C. P. Stehle, Bonn J.J. Strain, Coleraine I. Th orsdottir, Reykjavik K. Tontisirin, Nakhon Pathom R. Uauy, Santiago H. Vannucchi, Ribeirão Preto A. von Rücker, Bonn M. Wahlqvist, Clayton W. Waldhäusl, Vienna E. Wasantwisut, Salaya B. Watzl, Karlsruhe W.M. Windisch, Vienna T. Yoshikawa, Kyoto J. Zempleni, Lincoln, Nebr. A. Zittermann, Bad Oeynhausen Journal of Nutrition, Metabolic Diseases and Dietetics