Beetroot betalain inhibits peroxynitrite-mediated tyrosine nitration and DNA strand cleavage

Two major betalains, red-purple betacyanins and yellow betaxanthins, were isolated from red beetroots (Beta vulgaris L.), and their peroxynitrite (ONOO-) scavenging capacity was investigated. Apparent colours of the betalains were bleached by the addition of ONOO-, and the absorbance decreases were suppressed in the presence of glutathione, a ONOO- scavenger. After bleaching, a new absorption maximum was observed at 350 nm in the spectrum of the resulting reaction mixture. New peaks were detected from HPLC analysis of the reaction products of betanin, a representative constituent of red beetroot betacyanins, treated with ONOO- monitoring at 350 nm, and the intensity of the major peak was positively correlated with ONOO- concentration. Betanin inhibited the ONOO- (0.5 mM)-dependent nitration of tyrosine (0.1 mM). Additionally, the IC50 value of betanin (19.2 μM) was lower than that of ascorbate (79.6 μM). The presence of betanin (0.05-1.0 μM) also inhibited ONOO- (0.5 mM)-dependent DNA strand cleavage in a concentration-dependent manner. These results suggest that betalains can protect cells from nitrosative stress in addition to protecting them from oxidative stresses

Differential roles of breakfast only (one meal per day) and a bigger breakfast with a small dinner (two meals per day) in mice fed a high-fat diet with regard to induced obesity and lipid metabolism

<p>Abstract</p> <p>Background</p> <p>Recent studies on humans and rodents have suggested that the timing of food intake plays an important role in circadian regulation and metabolic health. Consumption of high-fat foods during the inactive period or at the end of the awake period results in weight gain and metabolic syndrome in rodents. However, the distinct effects of breakfast size and the breakfast/dinner size ratio on metabolic health have not yet been fully examined in mice.</p> <p>Methods</p> <p>We examined whether the parameters of metabolic syndrome were differentially affected in mice that consumed a large meal at the beginning of the awake period (breakfast; one meal group) and a relatively smaller meal at end of the awake period (dinner; two meals group). The mice of each group were provided equal food volume per day.</p> <p>Results</p> <p>Mice on one meal exhibited an increase in body weight gain, hyperinsulinemia, hyperleptinemia, and a decrease of gene expression associated with β-oxidation in adipose tissue and liver compared with those on two meals. The circadian expression pattern of the <it>Clock</it> gene in mice on one meal was disturbed compared with those on two meals.</p> <p>Conclusions</p> <p>In conclusion, a bigger breakfast with a smaller dinner (two meals per day) but not breakfast only (one meal per day) helps control body weight and fat accumulation in mice on a high-fat meals schedule. The findings of this study suggest that dietary recommendations for weight reduction and/or maintenance should include information on the timing and quantity of dietary intake.</p

Sigmoid colon carcinoma with focal neuroendocrine differentiation associated with ulcerative colitis: A case report

Introduction: Neuroendocrine tumors of the colon and rectum are relatively rare compared to sporadic colorectal carcinoma. There are few reports of neuroendocrine tumors of the colon and rectum in patients with ulcerative colitis. Presentation of case: A patient with sigmoid colon carcinoma with focal neuroendocrine features is presented. A 32-year-old man, who had been followed for ulcerative colitis for 14 years, was found to have carcinoma of the sigmoid colon on routine annual colonoscopy, and he underwent laparoscopic total colectomy. Pathologic examination showed sigmoid colon adenocarcinoma with focal neuroendocrine features. Discussion: Most colorectal carcinomas associated with inflammatory bowel disease are histologically similar to the sporadic type, and tumors with neuroendocrine features are very unusual. Conclusion: Very rare case of sigmoid colon carcinoma with neuroendocrine features arising in a patient with UC was described