Effects of zinc supplementation on glycemic control and oxidative stress in experimental diabetes: A systematic review.

INTRODUCTION: Diabetes mellitus (DM), an important public health problem worldwide, can cause imbalances in the homeostasis of trace elements such as zinc (Zn). It is possible that an adequate nutritional status related to nutrients is essential for the normal functioning of antioxidant defense systems, and any change in the concentration of these substances could increase the chances of DM complications. OBJECTIVE: To present a review on the effect of zinc supplementation on glycemic control and oxidative stress in experimental diabetes. METHODS: This is a systematic review of articles that investigated the effects of zinc supplementation on glycemic control and oxidative stress in diabetic rats. The PICOS strategy was used for the development of the research question, and the Syrcle tool for the quality assessment of the studies included in the review. Articles available in the PubMed, Scopus, and Web of Science databases were included without restriction on year of publication. The Syrcle tool was used to assess the risk of bias of the included studies. RESULTS: Fifteen studies were included in the review, seven of which evaluated glycemic control and oxidative stress after zinc supplementation, five only oxidative stress and three only glycemic control after zinc treatment. In all the studies included, diabetes was induced by the administration of streptozotocin (STZ) at doses ranging from 40 to 100 mg/kg. Zinc supplementation was made in the diet or drinking water or by gavage or intraperitoneal injection. The most used doses were 100 mg/kg of body weight by gavage and 0.32 and 0.64 g/kg in diet. The supplementation period ranged from 14 days to 8 weeks. Six studies revealed that zinc supplementation decreased fasting blood glucose as well as insulin resistance; nine studies included in this review reported decreased MDA concentration; in five studies, there was an increase in the activity of antioxidant enzymes (GPx, SOD, GSH and catalase); and one of the studies reported a reduction in glycated hemoglobin. CONCLUSION: Zinc supplementation improved hyperglycemia and revealed a protective potential against oxidative stress associated with experimental diabetes.

Functional performance, nutritional status and level of physical activity of elderly

The elderly is a risk group for changes in health conditions and as well as in functional performance related to the decline in grip strength and reduced walking speed, which can compromise the performance of activities of daily living. Based on this, the objective was to analyze the factors associated with functional performance in the elderly. For that, a cross-sectional study was developed involving a group of 179 elderly people who received medical care at an outpatient clinic of the public health network. Muscle strength and gait speed were measured. Nutritional status was determined by Body Mass Index (BMI), calf circumference (CC), waist circumference (WC) and waist-to-hip ratio (WHR). Level of physical activity was measured by the adapted version of the Minnesota Leisure Activities Questionnaire. Low muscle strength was found in 20.7% of the elderly and slow gait in 20.1%. Increased risk of cardiovascular disease was found in 40.8% considering WC, and 35.2% by WHR. Most of the elderly had low weight and no loss of muscle mass. Loss of muscle strength was associated with sex and CC and gait speed were associated with sex, age, and presence of a partner (p < 0.05). The chance of loss of muscle strength and lower gait speed was higher in elderly women. Loss of muscle mass due to CC was associated with the chance of loss of strength, and the chance of reduced walking speed was greater among the elderly individuals aged 75 years and over.

Consumo alimentar, pressão arterial e controle metabólico em idosos diabéticos hipertensos / Food intake, blood pressure and metabolic control in elderly hypertensive diabetic patients

Fundamentos: Hábitos alimentares inadequados têm sido asociados com o aumento de obesidade, diabetes tipo 2, hipercolesterolemia, doenças cardiovasculares e outras doenças crônicas não transmissíveis. Objetivo: Avaliar a associação entre ingestão inadequada de alimentos e níveis elevados de pressão arterial, glicemia e lipídeos séricos em idosos diabéticos e hipertensos inseridos na Estratégia Saúde da Família(ESF) atendidos em posto de saúde em Teresina(PI). Métodos: Pesquisa do tipo transversal, constituída por 34 idosos atendidos em demanda espontânea na unidade de saúde do Bairro Novo Horizonte. Foram analisados dados referentes à pressão arterial, à variavéis bioquímicas e ao consumo alimentar. A associação entre variáveis foi avaliação por meio do teste de Fisher para proporções e do teste de regressão linear. O nível de significância foi estabelecido em p<0,05. Resultados: Entre as variáveis investigadas houve associação entre a proporção de indivíduos com pressão arterial alteradae o consumo alimentar inadequado de frutas, hortaliças, leite e derivados, para pressão arterial sistólica e diastólica. Além disso, observou-se associação positiva entre percentual aumentadode hemoglobina glicada e o consumo inadequado de hortaliças (F=4,42; p=0,04), e entre os níveis elevados de triglicerídeos e o consumo inadequado de cereais (F=5,1; p=0,02). Conclusão: Os hábitos alimentares inadequados se apresentaram relacionados com aumento dos níveis de glicose e lipídiosséricos e com níveis pressóricos elevados no grupo de idosos avaliados.

Background: Poor eating habits have been associated with rising obesity, type 2 diabetes, hypercholesterolemia,cardiovascular diseases and other non-transmissible chronic diseases. Objective: To evaluate the association between inadequate food intake and high blood pressure with high levels of seric lipids and glycemia among elderly hypertensive diabetics assisted through the Family Health Strategy at a government clinic in Teresina, Piaui State, Northeast Brazil. Methods: A cross-sectional study of a sample of 34 elderly people assisted in response to spontaneous demands at a government clinic in the Novo Horizonte district analyzed data on blood pressure, biochemical variables and diet. Theassociations among the variables were evaluated through the Fisher test for proportions and the linear regression test, establishing a significance level of p<0.05. Results: Among the investigated variables, associationswere found between the proportion of individuals with altered blood pressure and inadequate intakes of fruits,vegetables, milk and dairy products for systolic and diastolic blood pressure. A positive association was noted betweenhigher glycated hemoglobin and insufficient consumption of vegetables (F=4.42; p=0.04), as well as between high triglyceride levels and insufficient consumption of cereals (F=5.1; p=0.02).Conclusion: Poor eating habits appear to be related to high blood pressure with higher glucose and seric lipid levels inthis elderly group.