Effects of chronic wine and alcohol intake on glutathione and malondialdehyde levels in rats

The Potential Benefit of Monitoring Oxidative Stress and Inflammation in the Prevention of Non-Communicable Diseases (NCDs)

The significant increase in worldwide morbidity and mortality from non-communicable diseases (NCDs) indicates that the efficacy of existing strategies addressing this crisis may need improvement. Early identification of the metabolic irregularities associated with the disease process may be a key to developing early intervention strategies. Unhealthy lifestyle behaviours are well established drivers of the development of several NCDs, but the impact of such behaviours on health can vary considerably between individuals. How can it be determined if an individual's unique set of lifestyle behaviours is producing disease? Accumulating evidence suggests that lifestyle-associated activation of oxidative and inflammatory processes is primary driver of the cell and tissue damage which underpins the development of NCDs. However, the benefit of monitoring subclinical inflammation and oxidative activity has not yet been established. After reviewing relevant studies in this context, we suggest that quantification of oxidative stress and inflammatory biomarkers during the disease-free prodromal stage of NCD development may have clinical relevance as a timely indicator of the presence of subclinical metabolic changes, in the individual, portending the development of disease. Monitoring markers of oxidative and inflammatory activity may therefore enable earlier and more efficient strategies to both prevent NCD development and/or monitor the effectiveness of treatment.

Characterization of dietary patterns and assessment of their relationships with metabolomic profiles: A community-based study

BACKGROUND & AIMS

Determining dietary patterns in China is challenging due to lack of external validation and objective measurements. We aimed to characterize dietary patterns in a community-based population and to validate these patterns using external validation cohort and metabolomic profiles.

DESIGN

We studied 5145 participants, aged 18-80 years, from two districts of Hangzhou, China. We used one district as the discovery cohort (N = 2521) and the other as the external validation cohort (N = 2624). We identified dietary patterns using a k-means clustering. Associations between dietary patterns and metabolic conditions were analyzed using adjusted logistic models. We assessed relationships between metabolomic profile and dietary patterns in 214 participants with metabolomics data.

RESULTS

We identified three dietary patterns: the traditional (rice-based), the mixed (rich in dairy products, eggs, nuts, etc.), and the high-alcohol diets. Relative to the traditional diet, the mixed (OR_adj = 1.7, CI 1.3-2.4) and the high-alcohol diets (OR_adj = 1.9, CI 1.3-2.7) were associated with type 2 diabetes and hypertension, respectively. Similar results were confirmed in the external validation cohort. In addition, we also identified 18 and 22 metabolites that could distinguish the mixed (error rate = 12%; AUC = 96%) and traditional diets (error rate = 19%; AUC = 88%) from the high-alcohol diet.

CONCLUSIONS

Despite the complexity of Chinese diet, identifying dietary patterns helps distinguish groups of individuals with high risk of metabolic diseases, which can also be validated by external population and metabolomic profiles.

Influence of Alcohol Consumption on Body Mass Gain and Liver Antioxidant Defense in Adolescent Growing Male Rats

The World Health Organization (WHO) reported that alcohol consumption is a serious problem in adolescents. The aim of the study was to assess the influence of the time of exposure of various alcoholic beverages on body mass as well as on select parameters of liver antioxidant defense in adolescent Wistar rats. Thirty-day-old animals were divided into 12 groups (six animals in each): control and groups receiving various beverages containing 10% of alcohol (ethanol, red wine, beer), observed for two, four, and six weeks. The body weight gain and energy supply were analyzed for body mass assessment. The catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase, transferase (GST), reductase activities, total antioxidant status, and glutathione level (GSH) were analyzed, for a liver antioxidant defense assessment. Group receiving red wine was characterized by the highest alcohol intake, lowest dietary intake, and highest total energy supply (p < 0.05). However, this did not influence body weight gain (p > 0.05). Reduced diet intake in groups receiving alcohol was counterbalanced by its energy value. Therefore, the energy supply was not lower than for the control (p > 0.05). Alcohol consumption and the experiment duration influenced CAT, SOD, and GST activities and GSH level. Alcohol consumption may influence hepatic antioxidant defense in adolescent male rats, but without influence on body weight gain.

A fast and validated method for the determination of malondialdehyde in fish liver using high-performance liquid chromatography with a photodiode array detector

Malondialdehyde (MDA) is a biomarker of lipid peroxidation and is present in foods and biological samples such as plasma. A high-performance liquid chromatography (HPLC) method was applied to determine MDA in fish liver samples after derivatization with 2,4-dinitrophenylhydrazine (DNPH) using a ODS2 column (10 cm × 4.6 mm, 3 μm) and a photodiode array detector. The mobile phase consisted of 0.2% acetic acid (v/v) in distilled water and acetonitrile (42:58, v/v). The present method was validated in terms of linearity, lower limit of quantification, lower limit of detection, precision, accuracy, recovery, and stability of MDA according to U.S. Food and Drug Administration (FDA) guidelines. The limit of quantification of MDA was 0.39 μmol/L, which is comparable to other methods. The recovery of the spiked MDA liver samples was in the range of 92.4% to 104.2%. This newly modified HPLC method is specific, sensitive, and accurate and allows the analysis of MDA within 4 min in fish liver but also in other tissues and plasma.

Determination of malondialdehyde by liquid chromatography as the 2,4-dinitrophenylhydrazone derivative: a marker for oxidative stress in cell cultures of human hepatoma HepG2

Malondialdehyde (MDA) is considered a presumptive biomarker for lipid peroxidation in live organisms and cultured cells. The present study adapts an accurate and reproducible method to measure MDA by high-performance liquid chromatography (HPLC) as its 2,4-dinitrophenylhydrazone derivative in human hepatoma HepG2 cells in culture. Since MDA is assumed to increase in conditions of cellular oxidative stress, two compounds that induce pharmacological oxidative stress in cell cultures, hydrogen peroxide (H(2)O(2)) and tert-butyl hydroperoxide (t-BOOH), have been used in HepG2 cells. The results report a significant increase in the content of MDA derivative after treatment with 200 and 500microM t-BOOH for 3h, while H(2)O(2) in doses up to 500microM failed to evoke a similar response, indicating a stronger lipid peroxidation of t-BOOH to HepG2 cells than H(2)O(2). Thus, MDA can be used as a reliable biomarker for cellular oxidative stress in human hepatoma HepG2.