Polysaccharide Fraction from Campomanesia adamantium and Campomanesia pubescens Attenuates 5-Fluorouracil-Induced Intestinal Mucosal Inflammation in Mice.

Gastrointestinal toxicity, including diarrhea and inflammation, is commonly observed with the use of 5-fluorouracil (5-FU). Several studies have shown that polysaccharides are interesting bioactive macromolecules for the treatment or prevention of gastrointestinal diseases. Therefore, in this study, the effect of a polysaccharide fraction from a mixture of two Guavira species (Campomanesia adamantium and Campomanesia pubescens), referred to here as CPW, on the development of intestinal mucositis was investigated. Intestinal mucositis was induced by a single injection of 5-FU (450 mg/kg), and various doses of CPW (3-100 mg/kg) were tested. CPW attenuated disease development and prevented small bowel dysmotility and colon shortening. CPW prevented the increase in villi width, crypt depth, and mucosal thickness in the duodenum, but not in the colon. Preservation of mucus, reduction of oxidative stress, inflammation, and prevention of the 5-FU-induced enlargement and swelling of the spleen were observed. In conclusion, this study demonstrated for the first time that CPW alleviates the intestinal damage induced by 5-FU and could be used as an adjuvant strategy during chemotherapy.

Tissue Proteases and Immune Responses: Influencing Factors of COVID-19 Severity and Mortality.

The coronavirus disease 19 (COVID-19) is caused by the highly transmissible severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has affected the global population despite socioeconomic status and amazed surveillance agencies for its incidence, mortality, and recovery rates. COVID-19 affects all age groups; however, it is suggested to progress into severe disease and cause mortality in over 10% of the confirmed cases, depending on the individual characteristics of the affected population. One of the biggest unanswered questions it is why only some individuals develop into the severe stages of the disease. Current data indicate that most of the critically ill are the elderly or those with comorbidities such as hypertension, diabetes, and asthma. However, it has been noted that, in some populations, severe disease is mostly observed in much younger individuals (<60-years old) with no reported underlying medical conditions. Certainly, many factors may contribute to disease severity including intrinsic host factors such as genetic variants, the expression levels of tissue proteins, among others. Considering all these aspects, this review aims to discuss how the expression levels of tissue proteases and the different profiles of immune responses influence the susceptibility to COVID-19 as well as disease severity and outcome.