Estudo da associação entre marcadores bioquímicos e do metabolismo redox, frequência de micronúcleo e sarcopenia em idosos

Abstract

Introduction: The etiology of sarcopenia is not well defined; studies suggest that different factors contribute to the development of this, including hormonal changes, loss of motor neurons, physical inactivity and use of medications. Another factor that may be associated together with oxidative stress is the frequency of micronucleus. However, to date it has not been reported in the literature studies investigating the association between the frequency of micronuclei and sarcopenia. Aim: to verify the association between biochemical markers, of redox metabolism, micronuclei frequency and sarcopenia in elderly residents in Uruguaiana city, RS. Methods: descriptive, comparative and exploratory cross-sectional study. The sample consisted of elderly treated at primary health care in the municipality of Uruguaiana, RS. The variables collected and investigated were divided into sociodemographic, anthropometric, haematological, biochemical (glucose, total cholesterol, triglycerides, high density lipoprotein linked to cholesterol (HDL-C), hepatic function (AST and ALT), renal function (urea, total protein and creatinine), and for REDOX metabolism (enzyme superoxide dismutase (SOD), catalase (CAT) activity, glutathione peroxidase (GPX), thiobarbituric acid-reactive substances (TBARS) and protein carbonylation), DNA damage (micronucleis frequency test). For determination of biomarkers venous blood samples were collected. For the anthropometric measurements were used: scale, stadiometer, tape measure and caliper. The tracking of sarcopenia was determined by the Lee formula: MM = height2 x (0.00744 x arm circumference2 + 0.00088 x thigh circumference2 + 0.00441 x calf circumference2) + 2.4 x sex - 0.048 x age + race + 7.8 and IMM = MM (kg)/ height (m) 2. And a correction was made to the subtraction of subcutaneous fat using the formula Cm = Climb_πS. To evaluate the functionality were applied tests: gait speed and grip strength with Jamar dynamometer. Results: the sample consisted of 168 elderly people, 62 men and 106 women, mean age 68.41 ± 6.13 years. Of these 49 (29.2%) were considered sarcopenic. The average levels of biochemical markers among non sarcopenic and sarcopenic groups were: Glucose 107.52 ± 49.46 and 103.57 ± 45.93 mg/ dL (p = 0648), total cholesterol 197.47 ± 46.93 and 177.43 ± 30.01 mg / dL (p = 0.010), HDL-C 47.53 ± 5.82 and 46.52 ± 6.55 mg / dL (p=0.354), triglycerides 160.30 ± 127.00 and 101.17 ± 66.55 mg / dl (p = 0.46). The means of REDOX metabolism markers among non sarcopenic and sarcopenic groups were: SOD = 0.1670 ± 0.05877 and 0.0916 ± 0.04585 U/ mg protein (p = 0.001), CAT = 2.0960 ± 0.48434 and 1.9720 ± 0.68767 U / mg protein (p = 0193), GPX = 1655.57 ± 191.61 and 1463.02 ± 228.11U / mg protein (p = 0.001), TBARS = 62.4983 ±16.07 e 83.2139 ± 21.50 nmol MDA / ml plasma (p = 0.001), protein carbonylation = 1.7019± 0.52 e 1.9506±0.67 nmol carbonyl / mg protein (p = 0.014), and the frequency of micronucleis = 5.50 ± 2.66 and 6.79 ± 2.84 (%) (p = 0.009). Conclusion: sarcopenic elderly have significantly higher average micronucleus frequency of lipid peroxidation (TBARS), protein carbonyls, on the other hand have also significantly lower average of antioxidant enzymes SOD, GPx, CAT and total cholesterol than non sarcopêncios elderly.