Chá verde versus Kombucha: potencial bioativo e efeitos no tratamento da colite ulcerativa em camundongos.

Abstract

Ulcerative colitis is an inflammatory bowel disease characterized by spontaneous and relapsing inflammation of the colon. Green tea and kombucha are beverages with high therapeutic potential, due to their high concentration of bioactive compounds, which gives its high antioxidant and anti-inflammatory potential. Thus, the present study aimed to carry out the physical-chemical, antioxidant and enzymatic characterization of green tea and kombucha through analyzes of pH, acidity, total solids content, determination of phenolic compounds, antioxidant potential through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and by the reaction to thiobarbituric acid reactive substances (TBARS) method, and enzymatic action (alpha-glucosidase), as well as to evaluate its anti-inflammatory potential against the model of induced ulcerative colitis by acetic acid (4%) in C57BL6 mice (n=72). The animals were randomly divided into six groups: control (n=12), control + green tea (n=12), control + kombucha (n=12), acetic acid (n=12), acetic acid + green tea (n=12 ) or acetic acid + kombucha (n=12). Treatments with green tea or kombucha were administered by gavage over 7 days, with food intake (FI) and disease activity index (DAI) being monitored. On the 8th day, the animals were euthanized and the determination of plasma levels of C-reactive protein (CRP) and macroscopic and microscopic analysis of the colon were performed. As a result, it was observed that kombucha had lower pH, higher acidity and total solids content compared to green tea. As for the concentration of total phenolic compounds by the Folin Ciocalteu method, there was no significant difference between the beverages (p>0.05). In the antioxidant analysis by the DPPH assay, it was observed that both green tea and kombucha showed significant antioxidant capacity in removing the DPPH radical, when compared to the control; however, when analyzing the inhibition of lipid peroxidation using the TBARS method, it was observed that green tea showed significant antioxidant capacity, whereas kombucha showed pro-oxidant capacity by this method. Both beverages showed significant inhibitory activity of the α-glucosidase enzyme, however, green tea showed a higher percentage of inhibition. Green tea and kombucha treatments showed intestinal anti-inflammatory effect in mice, significantly reducing the histological and macroscopic inflammation score. The treatments also reduced the plasma CRP levels of the colitic animals to levels similar to those of the control groups. Based on histological analysis of the colon, kombucha treatment proved to be the most effective, showing a significant reduction in intestinal crypt damage, in addition to attenuating the loss of goblet cells. None of the groups showed significant alterations in terms of FI and DAI. Based on the results presented, it can be concluded that both green tea and kombucha have high antioxidant and enzyme inhibition potential, as well as an anti-inflammatory therapeutic effect in induced ulcerative colitis in mice.