Can Oral Tolerance Explain the Inconsistencies Associated with Total Dietary Diversity and Colon Cancer? A Mechanistic Systematic Review

Is collagen supplementation friend or foe in rheumatoid arthritis and osteoarthritis? A comprehensive systematic review

Rheumatoid arthritis (RA) and osteoarthritis (OA) both are chronic diseases affecting joints. Immune response against collagen in both diseases may have a role in the initiation and progression of the disease. There is a hypothesis that suppression of immune response vs collagen could be a therapeutic approach in RA and OA. Exposure of gut immune system to collagen is a way to suppress immune response against collagen in the joints. So, the current systematic review is aimed to evaluate the effects of collagen supplementation in OA and RA patients. In the current systematic review, online electronic databases including PubMed/MEDLINE, Web of Sciences and Scopus were searched and finally 19 articles were included. The enrolled articles evaluated the effects of collagen supplementation on treatment of OA (n = 9) and RA (n = 10). Intact (n = 4) and hydrolyzed (n = 5) collagen were used to treat OA. All of the studies on RA used intact and type II collagen in their intervention. The last trials on collagen supplementation in RA and OA patients were performed in 2011 and 2016, respectively. High adverse effects of collagen supplementation and its low efficiency compared to routine treatments were reported by several included studies. Also, risk of bias assessment showed that most of the studies had poor quality. Therefore, it is not possible to definitely decide on the beneficial or detrimental effects of collagen supplementation on OA and RA patients. Further studies are needed to reach a final decision.

Levels of evidence for the association between different food groups/items consumption and the risk of various cancer sites: an umbrella review

This study aimed to determine the level of evidence on the association between food groups/items consumption and the risk of different cancer sites from the meta-analyses/pooled analyses of observational studies. A systematic search was executed in Scopus, PubMed/MEDLINE, and Web of Science. The criteria from the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) Expert Report were adopted for evidence grading. In summary, there was convincing evidence for the association between fibre intake and decreased risk of colon and breast cancer. Also, consumption of dairy products, milk, fruits, and fibre was associated with a probable decreased risk of breast cancer. Consumption of whole grains, dairy products, milk, fruits, vegetables, and fibre had a probable inverse association with the incidence risk of gastrointestinal tract cancers. More qualified studies are needed to find reliable findings on the association between various food groups/items consumption and the risk of different cancer sites.

The engineered probiotics for the treatment of chronic diseases: A systematic review

Engineered probiotics (EPs) are a group of probiotics whose proteome is manipulated by biotechnological techniques. EPs have attracted a lot of attention in recent researches for preventing and treating chronic diseases. The current study has been conducted to provide an overview regarding the EPs application in the treatment of chronic disease by a comprehensive systematic review of the published articles up to January 2022. To retrieve the related publications, three databases (PubMed/MEDLINE, Web of Sciences, and Scopus) were searched systematically. Finally, all human (n = 2) and animal (n = 37) studies were included. The included articles evaluated the effects of EPs on treatment of arthritis (n = 3), cancer (n = 2), autoimmune encephalomyelitis (EAE; n = 6), Parkinson disease (PD; n = 1), Alzheimer diseases (AD; n = 1), colitis (n = 11), celiac disease (n = 1), diabetes (n = 8) and cardiovascular disease (CVD; n = 6). Induction of oral tolerance (OT) is the most important mechanism of EPs action in the treatment of chronic disease. Providing oral vaccine and bioactive compounds are the other mechanisms of EPs action. PRACTICAL APPLICATIONS: The current systematic review gathered evidence about the application of EPs in the treatment of chronic diseases. Evidence suggests that EPs have very broad and potent effects in the treatment of chronic and even genetic diseases.

Dietary diversity score is associated with cardiometabolic risk factors in patients with hypertension (Hoveyzeh cohort study)

BACKGROUND: Dietary diversity score (DDS) is recognized as an essential factor of a high-quality diet. OBJECTIVE: To evaluate the relationship between DDS and cardiometabolic risk factors in hypertensive patients. METHODS: In this cross-sectional study, 972 hypertensive patients (322 males and 650 females) aged 35–70y participated were recruited. Dietary intake was evaluated using a semi-quantitative food frequency questionnaire and DDS was calculated. Metabolic syndrome was defined according to the IDF/AHA criteria. The anthropometric parameters, fasting blood sugar, lipid profile, and liver enzymes were measured. RESULTS: Male subjects who assigned to the top DDS tertile had 51% lower risk of having low serum HDL-C (OR: 0.49; 95% CI: 0.24–0.96) in the crude model. A similar association was observed for men in the second tertile of DDS after adjusting for covariates (OR: 0.47; 95% CI: 0.23–0.97). A significant inverse association was found between vegetable diversity score and odds of hyperglycemia in the male group in the adjusted model (OR: 0.44; 95% CI: 0.22–0.91). The vegetable diversity score was inversely associated with 67% decreased metabolic syndrome risk in the adjusted model (OR: 0.33; 95% CI: 0.15–0.70). CONCLUSION: These findings clarify the possible preventive role of higher DDS against metabolic syndrome.