Plasma antioxidants and oxidative stress status in obese women: correlation with cardiopulmonary response

Abstract

Introduction A high body fat coupled with low cardiopulmonary fitness and an increase in oxidative stress has been connoted as contributing factors in developing cardiovascular comorbidities. This study aimed to investigate the correlation between antioxidants and oxidative stress status with cardiopulmonary responses in women of different body mass index (BMI). Subjects and Methods Eighty female adults were recruited and divided into three groups; normal weight (n = 23), overweight (n = 28) and obese (n = 29), according to their BMI. Blood samples were obtained prior to cardiopulmonary exercise testing. Plasma samples were separated by centrifugation and analysed for enzymatic antioxidant activity including catalase, glutathione peroxidase and superoxide dismutase. Non-enzymatic antioxidant activities were assessed using 2, 2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging and ferric reducing ability of plasma (FRAP) assays. To evaluate the oxidative stress status of subjects, levels of reactive oxygen species and malondialdehyde, the by-product of lipid peroxidation, were measured. Cardiopulmonary responses were analysed using cardiopulmonary exercise testing (CPET) which involved 15 various parameters such as peak oxygen consumption, metabolic equivalents and respiratory exchange ratio. Results The obese group had significantly lower ABTS radical scavenging and FRAP activities than the normal weight group. A higher catalase activity was observed in the obese group than the normal weight group. Spearman’s correlation showed an inverse relationship between catalase and peak oxygen consumption, while partial correlation analysis showed inverse correlations between superoxide dismutase and respiratory frequency, ABTS activity and oxygen pulse, and between ABTS activity and cardiac output. Conclusion Our results demonstrate a lower cardiovascular fitness and antioxidant capacity in obese women; the higher catalase activity may be a compensatory mechanism. The negative correlations found between these two parameters may indicate the potential effect of antioxidants on the cardiopulmonary system and deserve further analysis in a larger population. Nevertheless, this study provides the basis for future studies to further explore the relationships between redox status and cardiopulmonary responses. This can potentially be used to predict future risk of developing diseases associated with oxidative stress, especially pulmonary and cardiovascular diseases.

Impaired Antioxidant Defence Status Is Associated With Metabolic-Inflammatory Risk Factors in Preterm Children With Extrauterine Growth Restriction: The BIORICA Cohort Study

“…This enzyme initially responds to OxS and can act as a compensation mechanism to enhance the antioxidant defence system and counteract the production of free radicals, which may be related with the adequate development of these children that was not observed in the EUGR group. This "protective phenomenon" has also been observed in pathological conditions characterised by greater exposure to free radicals and the presence of OxS, such as FGR (37), obesity (46), and diabetes (47). This hypothesis might also be related to the higher concentrations of retinol and β-carotene observed in preterm children vs. the controls in our study (Table 2).…”

Stachys sieboldii Miq. Root Attenuates Weight Gain and Dyslipidemia in Rats on a High-Fat and High-Cholesterol Diet

“…Adipose tissue accumulation in obesity increases the number of macrophages, leading to local inflammation [ 41 ]. This leads to the production of proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) [ 42 ]. Macrophage accumulation and local inflammation result in metabolic dysfunction, eventually leading to systemic inflammation and atherosclerosis [ 39 ].…”

“…High levels of circulating glucose and lipids could increase the production of reactive oxygen species (ROS) [ 43 ]. Imbalanced ROS levels lead to increased oxidative stress, which could damage proteins, carbohydrates, lipids and DNA, resulting in several chronic diseases such as cardiovascular disease, diabetes and cancer [ 42 ]. Antioxidants protect against such diseases by scavenging excessively produced ROS, inhibiting ROS formation, reducing the oxidation of cellular molecules, alleviating oxidative stress and binding to metal ions [ 44 ].…”

Association between Food Intake, Clinical and Metabolic Markers and DNA Damage in Older Subjects

“…This enzyme is involved in the conversion of H 2 O 2 to hydrogen and water. Some studies have reported higher catalase activity in overweight/obese subjects compared to lean individuals as a compensatory mechanism to counterbalance an oxidative stress condition and an increase in the metabolic production of H 2 O 2 in these subjects [ 64 , 65 ]. Although this could partially explain the inverse correlation found between DNA damage and BMI, the lack of data on enzymatic activity and the mild overweight of the subjects makes this consideration only a speculation.…”