Proanthocyanidins at the gastrointestinal tract: mechanisms involved in their capacity to mitigate obesity-associated metabolic disorders

Oxygen influences in vitro assessment for phenolic compounds: Digestive stability, α-glucosidase inhibitory activity and bioavailability

Phenolic compounds are popular in screening novel hypoglycemic agents, but the impact of oxidative degradation on the determination of α-glucosidase inhibitory activity and bioavailability is unclear. Here we showed 12 phenolic compounds structure-dependently degraded during standard simulated digestion, while in physiological hypoxia their retention rates were all over 87.89 %. This enhancement of digestive stability resulted in the biggest drop of 31.72 % in IC50 against α-glucosidase and a significant increase in bioavailability. Enzyme kinetic and multi-spectroscopic analysis confirmed oxygen weakened the affinity of compounds to α-glucosidase, but the mechanisms were not changed. Moreover, a two-chamber culture system was designed to meet conflicting demands for oxygen between epithelium and cavity, and better α-glucosidase inhibitory activities (51.61 % maximum reduction in glucose production) and absorption rates (up to 1.10 % from undetectable) were obtained than those of uncontrolled oxygen. Hence, the oxygen level should be monitored to assess the activities of phenolic compounds in vitro.

Relationship between Cardiometabolic index and endometriosis in a US nationally representative sample: results from NHANES 1999-2006

Background

Endometriosis is an estrogen-dependent gynecological endocrine condition and a systemic inflammatory disease associated to improper lipid metabolism and increased cardiovascular risk. The Cardiometabolic Index (CMI) is a novel indicator representing visceral adipose tissue distribution and metabolic dysfunction, integrating lipid metabolism indicators and the waist-to-height ratio. While anomalies in lipid metabolism are often associated with (BMI) Body Mass Index, literature consistently shows a negative link between endometriosis and female BMI, and some studies have found that endometriosis is one of the few reproductive diseases not persistently positively correlated with obesity. Given the limitations of BMI, a comprehensive index like CMI is crucial for exploring the incidence of endometriosis. Currently, research on the correlation between CMI and endometriosis is lacking, prompting this study to investigate this association.

Objective

To investigate the association between the CMI and the risk of having endometriosis in a sample representing the entire U.S. population.

Study design

A cross-sectional analysis was conducted using data from four cycles of the National Health and Nutrition Examination Survey (NHANES) spanning the years 1999 to 2006. The study included individuals aged 20 to 54 with a documented history of endometriosis and complete CMI data. Logistic regression analysis, subgroup and interaction analyses, smooth curve fitting, and restricted cubic splines (RCS) were utilized to examine the association between CMI and endometriosis.

Results

The study found that individuals with higher CMI had an increased probability of developing endometriosis. This relationship remained significant after adjusting for potential confounders such as age, ethnicity, Poverty Income Ratio (PIR), drinking, smoking, education level, and marital status. The fully adjusted model revealed a positive correlation between CMI and endometriosis (OR = 1.21; 95% CI, 1.04-1.40, p < 0.05). Subgroup and interaction analyses showed no significant effect modification by age, BMI, PIR, hypertension, drinking, smoking, or menarche age (all p-values for interaction > 0.05).

Conclusion

Our study shows a link between CMI and the chance of getting endometriosis.Due to the common occurrence of endometriosis and the lack of clarity surrounding their cause, more study is needed to confirm our results and find out if CMI could be used as a warning sign for endometriosis.

Polyphenols: Chemistry, bioavailability, bioactivity, nutritional aspects and human health benefits: A review

Polyphenols, including phenolics, alkaloids, and terpenes, are secondary metabolites that are commonly found in fruits, vegetables, and beverages, such as tea, coffee, wine, chocolate, and beer. These compounds have gained considerable attention and market demand because of their potential health benefits. However, their application is limited due to their low absorption rates and reduced tissue distribution efficiency. Engineering polyphenol-protein complexes or conjugates can enhance the antioxidant properties, bioavailability, and stability of polyphenols and improve digestive enzyme hydrolysis, target-specific delivery, and overall biological functions. Complex polyphenols, such as melanin, tannins, and ellagitannins, can promote gut microbiota balance, bolster antioxidant defense, and improve overall human health. Despite these benefits, the safety of polyphenol complexes must be thoroughly evaluated before their use as functional food additives or supplements. This review provides a detailed overview of the types of macromolecular polyphenols, their chemical composition, and their role in food enrichment. The mechanisms by which complex polyphenols act as antioxidative, anti-inflammatory, and anticancer agents have also been discussed.

Role of Food Digestion and Digestive System in the Nutritional, Functional and Health Properties of Food Bioactives

The impact of food components on the human digestive system is an important area of research in the fields of nutrition and food science [...].

The Autoxidized Mixture of (-)-Epicatechin Contains Procyanidins and Shows Antiproliferative and Apoptotic Activity in Breast Cancer Cells

For this study, procyanidins generated through the autoxidation of (-)-epicatechin (Flavan-3-ol) under mildly acidic conditions (pH = 6.0) were characterized with ultra high-performance liquid chromatography (UHPLC) coupled with tandem mass spectrometry (MS/MS). Two procyanidins (types A and B) and a mix of oligomers were generated through the autoxidation of (-)-epicatechin. The antiproliferative activity of this mixture of procyanidins on MDA-MB-231, MDA-MB-436, and MCF-7 breast cancer cells was evaluated. The results indicate that the procyanidin mixture inhibited the proliferation of breast cancer cells, where the activity of the procyanidin mixture was stronger than that of (-)-epicatechin. Moreover, the mechanism underlying the antiproliferative activity of procyanidins was investigated. The resulting data demonstrate that the procyanidins induced apoptotic cell death in a manner selective to cancerous cells. In particular, they caused the activation of intrinsic and extrinsic apoptotic pathways in the breast cancer cells. The findings obtained in this study demonstrate that the generation of procyanidins in vitro by the autoxidation of (-)-epicatechin has potential for the development of anti-breast cancer agents.

The synergistic ramification of insoluble dietary fiber and associated non-extractable polyphenols on gut microbial population escorting alleviation of lifestyle diseases

Most of the pertinent research which aims at exploring the therapeutic effects of polyphenols usually misapprehends a large fraction of non-extractable polyphenols due to their poor aqueous-organic solvent extractability. These polymeric polyphenols (i.e., proanthocyanins, hydrolysable tannins and phenolic acids) possess a unique property to adhere to the food matrix polysaccharides and protein sowing to their structural complexity with high glycosylation, degree of polymerization, and plenty of hydroxyl groups. Surprisingly resistance to intestinal absorption does not hinder its bioactivity but accelerates its functionality manifolds due to the colonic microbial catabolism in the gastrointestinal tract, thereby protecting the body from local and systemic inflammatory diseases. This review highlights not only the chemistry, digestion, colonic metabolism of non-extractable polyphenols (NEPP) but also summarises the synergistic effect of matrix-bound NEPP exerting local as well as systemic health benefits.

Proanthocyanidins: Impact on Gut Microbiota and Intestinal Action Mechanisms in the Prevention and Treatment of Metabolic Syndrome

The metabolic syndrome (MS) is a cluster of risk factors, such as central obesity, hyperglycemia, dyslipidemia, and arterial hypertension, which increase the probability of causing premature mortality. The consumption of high-fat diets (HFD) is a major driver of the rising incidence of MS. In fact, the altered interplay between HFD, microbiome, and the intestinal barrier is being considered as a possible origin of MS. Consumption of proanthocyanidins (PAs) has a beneficial effect against the metabolic disturbances in MS. However, there are no conclusive results in the literature about the efficacy of PAs in improving MS. This review allows a comprehensive validation of the diverse effects of the PAs on the intestinal dysfunction in HFD-induced MS, differentiating between preventive and therapeutic actions. Special emphasis is placed on the impact of PAs on the gut microbiota, providing a system to facilitate comparison between the studies. PAs can modulate the microbiome toward a healthy profile and strength barrier integrity. Nevertheless, to date, published clinical trials to verify preclinical findings are scarce. Finally, the preventive consumption of PAs in MS-associated dysbiosis and intestinal dysfunction induced by HFD seems more successful than the treatment strategy.