Changes in the Microbiota and their Roles in Patients with Type 2 Diabetes Mellitus

Edible traditional Chinese medicines improve type 2 diabetes by modulating gut microbiotal metabolites

Type 2 diabetes mellitus (T2DM) is a metabolic disorder with intricate pathogenic mechanisms. Despite the availability of various oral medications for controlling the condition, reports of poor glycemic control in type 2 diabetes persist, possibly involving unknown pathogenic mechanisms. In recent years, the gut microbiota have emerged as a highly promising target for T2DM treatment, with the metabolites produced by gut microbiota serving as crucial intermediaries connecting gut microbiota and strongly related to T2DM. Increasingly, traditional Chinese medicine is being considered to target the gut microbiota for T2DM treatment, and many of them are edible. In studies conducted on animal models, edible traditional Chinese medicine have been shown to primarily alter three significant gut microbiotal metabolites: short-chain fatty acids, bile acids, and branched-chain amino acids. These metabolites play crucial roles in alleviating T2DM by improving glucose metabolism and reducing inflammation. This review primarily summarizes twelve edible traditional Chinese medicines that improve T2DM by modulating the aforementioned three gut microbiotal metabolites, along with potential underlying molecular mechanisms, and also incorporation of edible traditional Chinese medicines into the diets of T2DM patients and combined use with probiotics for treating T2DM are discussed.

Structure properties of Canna edulis RS3 (double enzyme hydrolysis) and RS4 (OS-starch and cross-linked starch): Influence on fermentation products and human gut microbiota

This study investigated the in vitro fermentation characteristics of different structural types of Canna edulis resistant starch (RS). RS3 was prepared through a double enzyme hydrolysis method, and RS4 (OS-starch and cross-linked starch) was prepared using octenyl succinic anhydride and sodium trimetaphosphate/sodium tripolyphosphate, respectively. The RS3 and RS4 samples were structurally analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction analysis. This was followed by in vitro fermentation experiments. The results revealed microstructure differences in the two groups of starch samples. Compared to native starch, RS3 and RS4 exhibited a lower degree of order and endothermic energy, with lower crystallinity (RS3: 29.59 ± 1.11 %; RS4 [OS-starch]: 28.01 ± 1.32 %; RS4 [cross-linked starch]: 30.44 ± 1.73 %) than that in native starch (36.29 ± 0.89 %). The RS content was higher in RS3 (63.40 ± 2.85 %) and RS4 (OS-starch: 71.21 ± 1.28 %; cross-linked starch: 74.33 ± 0.643 %) than in native starch (57.71 ± 2.95 %). RS3 and RS4 exhibited slow fermentation rates, promoting the production of short-chain fatty acids. RS3 and cross-linked starch significantly increased the production of acetate and butyrate. Moreover, RS3 significantly promoted the abundance of Lactobacillus, while OS-starch and cross-linked starch significantly enhanced the abundance of Dorea and Coprococcus, respectively. Hence, the morphological structure and RS content of the samples greatly influenced the fermentation rate. Moreover, the different varieties of RS induced specific gut microbial regulation. Hence, they show potential applications in functional foods for tailored gut microbiota management.

Gut microbiota dysbiosis -associated obesity and its involvement in cardiovascular diseases and type 2 diabetes. A systematic review

INTRODUCTION

Obesity is a complex, multifactorial disease caused by various factors. Recently, the role of the gut microbiota in the development of obesity and its complications has attracted increasing interest.

PURPOSE

This article focuses on the mechanisms by which gut microbiota dysbiosis induces insulin resistance, type 2 diabetes, and cardiovascular diseases linked to obesity, highlighting the mechanisms explaining the role of gut microbiota dysbiosis-associated inflammation in the onset of these pathologies.

METHODS

A systematic study was carried out to understand and summarize the published results on this topic. More than 150 articles were included in this search, including different types of studies, consulted by an online search in English using various electronic search databases and predefined keywords related to the objectives of our study.

RESULTS

We have summarized the data from the articles consulted in this search, and we have found a major gut microbiota alteration in obesity, characterized by a specific decrease in butyrate-producing bacteria and the production of metabolites and components that lead to metabolic impairments and affect the progression of various diseases associated with obesity through distinct signaling pathways, including insulin resistance, type 2 diabetes, and cardiovascular diseases (CVD). We have also focused on the major role of inflammation as a link between gut microbiota dysbiosis and obesity-associated metabolic complications by explaining the mechanisms involved.

CONCLUSION

Gut microbiota dysbiosis plays a crucial role in the development of various obesity-related metabolic abnormalities, among them type 2 diabetes and CVD, and represents a major challenge for chronic disease prevention and health. Indeed, the intestinal microbiota appears to be a promising target for the nutritional or therapeutic management of these diseases.

Dietary Supplementation with a Cocoa-Carob Blend Modulates Gut Microbiota and Prevents Intestinal Oxidative Stress and Barrier Dysfunction in Zucker Diabetic Rats

We have recently developed a cocoa-carob blend (CCB) rich in polyphenols with antidiabetic properties. In this study, we investigated whether its benefits could be related to gut health and gut microbiota (GM) composition and the likely phenolic metabolites involved. Zucker diabetic fatty rats were fed on a standard or a CCB-rich diet for 12 weeks. Intestinal barrier structure and oxidative and inflammatory biomarkers were analyzed in colonic samples. GM composition and phenolic metabolites were evaluated from feces. The results show that CCB improved mucin and tight-junction proteins and counteracted gut oxidative stress and inflammation by regulating sirtuin-1 and nuclear factor erythroid 2-related factor 2 (Nrf2) levels. CCB also modulated the composition of the GM, showing increases in Akkermansia and Bacteroides and decreases in Ruminococcus genera. Correlation analysis strengthened the associations between these genera and improved pathological variables in diabetic animals. Moreover, 12 phenolic metabolites were identified in CCB feces, being2,3-dihydroxybenzoic and 3,4,5-trihydroxybenzoic acids significantly associated with increased levels of Akkermansia and Oscillospira genera. Our findings support the potential use of CCB to prevent intestinal damage and dysbiosis in T2D, which would help to delay the progression of this pathology.

Effects of gut microbiota on neurodegenerative diseases

A progressive degradation of the brain's structure and function, which results in a reduction in cognitive and motor skills, characterizes neurodegenerative diseases (NDs) such as Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). The morbidity linked to NDs is growing, which poses a severe threat to human being's mental and physical ability to live well. The gut-brain axis (GBA) is now known to have a crucial role in the emergence of NDs. The gut microbiota is a conduit for the GBA, a two-way communication system between the gut and the brain. The myriad microorganisms that make up the gut microbiota can affect brain physiology by transmitting numerous microbial chemicals from the gut to the brain via the GBA or neurological system. The synthesis of neurotransmitters, the immunological response, and the metabolism of lipids and glucose have all been demonstrated to be impacted by alterations in the gut microbiota, such as an imbalance of helpful and harmful bacteria. In order to develop innovative interventions and clinical therapies for NDs, it is crucial to comprehend the participation of the gut microbiota in these conditions. In addition to using antibiotics and other drugs to target particular bacterial species that may be a factor in NDs, this also includes using probiotics and other fecal microbiota transplantation to maintain a healthy gut microbiota. In conclusion, the examination of the GBA can aid in understanding the etiology and development of NDs, which may benefit the improvement of clinical treatments for these disorders and ND interventions. This review indicates existing knowledge about the involvement of microbiota present in the gut in NDs and potential treatment options.