Avaliação da influência da dieta em parâmetros de estresse oxidativo, inflamação e modificações epigenéticas em pacientes com lúpus eritematoso sistêmico

Abstract

Exacerbated cellular activation due to autoimmunity in Systemic Lupus Erythematosus (SLE) can generate an imbalance between antioxidants and pro-oxidants, triggering oxidative stress. In addition to oxidative stress, chronic inflammation in SLE is a risk factor for developing metabolic diseases. It is known that food plays an important role in modulating oxidative stress and inflammation through the intake of nutrients that enhance or destabilize these aspects. The study aimed to evaluate whether a diet with antioxidant and anti-inflammatory potential can modulate oxidative stress, inflammation and epigenetic modifications in patients with SLE. For this, a review article was first developed covering the methodologies and nutritional tools applied to evaluate the diet profile and the influence on the progression of SLE. From the review article, it was possible to observe that the available literature reveals a diversity in the results investigated with heterogeneity in the methodologies and instruments for assessing diet quality and collecting dietary data, resulting in varied conclusions about the relationship between diet and SLE. Subsequently, a study was carried out with 40 participants, 20 patients diagnosed with SLE and 20 control individuals. Nutritional data were collected using the food frequency questionnaire (FFQ) and evaluated using previously validated dietary indices. Essential and non-essential elements, biomarkers of oxidative stress and inflammation, DNA damage, and global DNA methylation were assessed in all participants. The biomarkers of oxidative stress, TBARS, non-protein thiols, catalase, FRAP and vitamin C did not show significant differences between SLE patients and the control group. However, higher levels of nitric oxide were observed in patients with SLE compared to the control group, in addition to a positive correlation with disease activity. Patients with SLE who had more significant disease activity had lower plasma selenium levels. An increase in the expression of β2-integrins in neutrophils was also observed in patients with more significant renal impairment and elevated levels of vitamin C in plasma in patients with a lower percentage of expression of ICAM-1 and β2-integrins in neutrophils. Patients with SLE showed hypomethylation in relation to controls and global DNA methylation negatively correlated with aspects of disease activity. Furthermore, patients with SLE showed greater cell expression with micronuclei than controls. Regarding food, it was observed that daily consumption of the macronutrients recommended above may be associated with worse disease activity in patients with SLE. The dietary index assesses the anti-inflammatory potential of the diet correlated with the lipid peroxidation biomarker, and the dietary index assesses the antioxidant potential correlated with non-protein thiols. Therefore, although the existing literature presents significant heterogeneity in its conclusions, it is possible to observe that diet impacts SLE activity. Biomarkers related to disease activity and dietary patterns that may interfere with oxidative stress were identified. A more comprehensive evaluation of diet and SLE with a more significant number of participants is necessary to understand biological changes better and, especially, evaluate the impact of diet on this disease.