Selenium-enriched and ordinary green tea extracts prevent high blood pressure and alter gut microbiota composition of hypertensive rats caused by high-salt diet

Effects of Salinity on Physicochemical Properties, Flavor Compounds, and Bacterial Communities in Broad Bean Paste-Meju Fermentation

Broad bean paste (BBP) is a traditional fermented soy food, and its high salt content not only prolongs the fermentation time but also threatens human health. In this study, three BBP-meju with different salt concentrations were prepared, and the effects of varying salinity on fermentation were comprehensively compared. The results showed that salt-reduced fermentation contributed to the accumulation of amino acid nitrogen, reducing sugars, free amino acids, and organic acids. Alcohols, esters, aldehydes, and acids were the main volatile flavor compounds in BBP-meju, and the highest total volatile flavor compounds were found in medium-salt meju. Bacillus, Staphylococcus, Aspergillus, and Mortierella were the dominant microbial communities during fermentation, and there were also three opportunistic pathogens, Enterobacter, Pantoea, and Brevundimonas, respectively. According to Spearman correlation analysis, Wickerhamomyces, Bacillus, Staphylococcus, and Mortierella all showed highly significant positive correlations with ≥3 key flavor compounds, which may be the core functional flora. Furthermore, the dominant microbial genera worked synergistically to promote the formation of high-quality flavor compounds and inhibit the production of off-flavors during salt-reduced fermentation. This study provides a theoretical reference for the quality and safety control of low-salt fermented soy foods.

Association between socio-demographic factors, lifestyle, eating habits and hypertension risk among middle-aged and older rural Chinese adults

BACKGROUND AND AIMS

Hypertension is a global health issue with increasing prevalence. This study aimed to understand the epidemiological characteristics and influencing factors of hypertension in rural Chinese populations and help develop effective prevention and control strategies.

METHODS AND RESULTS

This cross-sectional study used database from the Early Diagnosis and Early Treatment Project of Esophageal Cancer conducted in a rural population from September 2012 to December 2017. A total of 10,111 subjects aged 35-75 years residing in Huai'an District, Huai'an City, Jiangsu Province for at least three years were included. Unconditional univariate and multivariate logistic regression models were performed to evaluate the association between socio-demographic information, lifestyle habits, dietary characteristics and the risk of hypertension. The prevalence of hypertension was 34.32 % in this rural population. Men and older individuals are more likely to have hypertension when compared with women and young individuals, respectively. Factors associated with an increased risk of hypertension included: fast eating speed, a high-salt diet (both currently and ten years ago), a high-spicy diet ten years ago, high BMI, poor educational attainment, preference for fatty meats, hot diet, green tea drinking, intake of pickled potherb mustard and corn flour, family smoking and alcohol consumption. Light smoking in males, consumption of fruits, adzuki bean, and pork liver were associated with reduced risk of hypertension.

CONCLUSIONS

The study identified some factors, including eat habits and lifestyle, associated with hypertension risk, and highlighted the need for targeted policies and interventions in rural China to address potential risk factors for hypertension.

Probiotics Bifidobacterium lactis M8 and Lactobacillus rhamnosus M9 prevent high blood pressure via modulating the gut microbiota composition and host metabolic products

IMPORTANCE

Elevated blood pressure affects 40% of the adult population, which accounts for high cardiovascular disease risk and further high mortality yearly. The global understanding of the gut microbiome for hypertension may provide important insights into the prevention. Bifidobacterium lactis M8 and Lactobacillus rhamnosus M9 originated from human breast milk, were able to decrease blood pressure, and modified metabolites in a high fructose-induced elevated blood pressure mouse model. Moreover, we found there was a close relationship between unexplored gut microbes and elevated blood pressure. Also, subsequently, the cross-link was explored among gut microbes, metabolites, and some metabolic pathways in gut microbial environment through introducing novel prediction methodology and bioinformatic analysis. It allowed us to hypothesize that probiotics can prevent elevated blood pressure via gut microbiota and related metabolism.Thus, utilization of dietary strategies (such as probiotics) to maintain the blood pressure level is of crucial importance.

Effects of green tea catechin on the blood pressure and lipids in overweight and obese population-a meta-analysis

Background

Overweight and obesity as main health problems harm human beings worldwide. The number of people diagnosed with overweight and obese is gradually increasing. Green tea catechin has been reported to effectively help control body weight in overweight and obese population, and is protectively against the blood pressure and lipids in people with type 2 diabetes and metabolic syndrome.

Methods

We retrieved 4 English databases (PubMed, Web of science, Cochrane, Scoups) from inception to April 20, 2023. Two reviewers independently determined eligibility, assessed the reporting quality of included studies, and extracted the data. Data were extracted from eleven studies. The results were presented with the weighted mean differences (WMDs), and the confidence intervals (CIs) was 95 %. The random-effects or fixed-effects model was applied according to the heterogeneity. The subgroup analysis was used to identify the source of heterogeneity. Publication bias was evaluated using funnel plots, Egger's test, and Begg's test.

Results

Eleven randomized controlled trials (RCTs) inclusion studies were screened from 3072 literature articles, involving 613 overweight and obese patients. After combining all studies, it was found that in overweight and obese people green tea catechin could reduce waist circumference (WC) (pooled WMD = -1.37 cm, 95 % CI: -2.52 to -0.22 cm, p = 0.019), and triglyceride (TG) (pooled WMD = -0.18 mmol/L, 95 % CI: -0.35 to -0.02 mmol/L, p = 0.032), and increase high density lipoprotein cholesterol (HDL-c) (pooled WMD = 0.07 mmol/L, 95 % CI: 0.01-0.14 mmol/L, p = 0.031).

Conclusion

Green tea catechin supplement effectively reduced WC and TG levels and improved HDL-c levels. However, it did not show the significant effect on the blood pressure in overweight and obese people. The present meta-analysis showed a moderate benefit of green tea catechin supplementation on lipid profiles in overweight and obese people.

Impacts of selenium enrichment on nutritive value and obesity prevention of Cordyceps militaris: A nutritional, secondary metabolite, and network pharmacological analysis

This study aimed to compare the nutritive value and obesity prevention of ordinary Cordyceps militaris (CM) and selenium-enriched CM (SeCM). The results indicated that Se enrichment significantly increased the total carbohydrate and soluble dietary fiber content, while the protein and insoluble dietary fiber content decreased. Although the fat content was not affected, the medium and long-chain fatty acids content significantly changed. Moreover, Se enrichment significantly elevated the secondary metabolites belonging to terpenoids and alkaloids, which are linked with the enhanced biosynthesis of secondary metabolites. Both CM and SeCM reduced body weight, adipose accumulation, impaired glucose tolerance, and lipid levels in high-fat diet (HFD)-fed mice, and there was no significant difference between them. Network pharmacological analysis revealed that dietary CM and SeCM prevented HFD-induced obesity and associated metabolic diseases with multi-ingredients acting on multi-targets. Overall, Se enrichment improved the nutritive value of CM without altering its role in preventing obesity.

Regulation of glucolipid metabolism and gut microbiota by green and black teas in hyperglycemic mice

A high-sugar and -fat diet (HSFD) has become a primary risk factor for diabetes, and dietary intervention shows a substantial effect on the prevention and management of hyperglycemia. In this study, the chemical compositions of the aqueous extracts of stir-fried green tea (GT) and congou black tea (BT) were compared. Moreover, their potential mechanisms and regulatory effects on hepatic glycolipid metabolism and gut microbiota disorders in hyperglycemic mice were further explored. Our results show that GT or BT intervention had a prominent regulatory effect on glycolipid metabolism. Moreover, they could significantly regulate the levels of serum metabolic signatures, the activities of key enzymes in liver glucose metabolism, and the expression of genes or proteins related to glycolipid metabolism via activating the IRS-1-PI3K/AKT-GLUT2 signaling pathway. Significantly, GT or BT administration adjusted the composition and diversity of the gut microbiota, mainly reflecting a significant increase in the abundance of beneficial bacteria (including Allobaculum, Lactobacillus, and Turicibacter) and reducing the abundance of harmful or conditionally pathogenic bacteria (mainly including Clostridiales and Bacteroides). Our results suggest that dietary supplementation with GT or BT could exert a practical anti-diabetic effect. Meanwhile, BT intervention showed a better regulation effect on glycolipid metabolism. This study reveals that GT and BT have excellent potential for developing anti-diabetic food.

Selenium-Enriched and Ordinary Black Teas Regulate the Metabolism of Glucose and Lipid and Intestinal Flora of Hyperglycemic Mice

Black tea is one of the six major tea categories and has a variety of bioactivities. However, little is known about its comprehensive evaluation of hypoglycemic effects and potential mechanisms. In this study, we investigated the in vivo hypoglycemic activity and potential mechanism for aqueous extracts of ordinary black tea (BT) and selenium-enriched black tea (Se-BT) by using an established high-fat diet together with streptozotocin (STZ)-induced hyperglycemic mouse model. Additionally, we also explored their α-glucosidase inhibition activity. The results show that both BT and Se-BT had a favorable glycosidase inhibitory activity. Moreover, the intervention of BT and Se-BT could regulate the mRNA expression and the level of serum parameters related to glucose and lipid metabolisms. Accordingly, they could activate the phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) signaling pathway and alleviate insulin resistance (IR) and hyperglycemia. Moreover, supplementation of BT and Se-BT increased the richness and diversity of intestinal flora and altered the abundance of beneficial and harmful bacteria. Both BT and Se-BT could regulate glucose metabolism, alleviate tissue damage, and restore intestinal flora dysbiosis, suggesting that they could be used as a natural functional food for preventing hyperglycemia.

Special tea products featuring functional components: Health benefits and processing strategies

The functional components in tea confer various potential health benefits to humans. To date, several special tea products featuring functional components (STPFCs) have been successfully developed, such as O-methylated catechin-rich tea, γ-aminobutyric acid-rich tea, low-caffeine tea, and selenium-rich tea products. STPFCs have some unique and enhanced health benefits when compared with conventional tea products, which can meet the specific needs and preferences of different groups and have huge market potential. The processing strategies to improve the health benefits of tea products by regulating the functional component content have been an active area of research in food science. The fresh leaves of some specific tea varieties rich in functional components are used as raw materials, and special processing technologies are employed to prepare STPFCs. Huge progress has been achieved in the research and development of these STPFCs. However, the current status of these STPFCs has not yet been systematically reviewed. Here, studies on STPFCs have been comprehensively reviewed with a focus on their potential health benefits and processing strategies. Additionally, other chemical components with the potential to be developed into special teas and the application of tea functional components in the food industry have been discussed. Finally, suggestions on the promises and challenges for the future study of these STPFCs have been provided. This paper might shed light on the current status of the research and development of these STPFCs. Future studies on STPFCs should focus on screening specific tea varieties, identifying new functional components, evaluating health-promoting effects, improving flavor quality, and elucidating the interactions between functional components.

A Review of Plant Selenium-Enriched Proteins/Peptides: Extraction, Detection, Bioavailability, and Effects of Processing

As an essential trace element in the human body, selenium (Se) has various physiological activities, such as antioxidant and anticancer activity. Selenium-enriched proteins/peptides (SePs/SePPs) are the primary forms of Se in plants and animals, and they are the vital carriers of its physiological activities. On the basis of current research, this review systematically describes the extraction methods (aqueous, alkaline, enzymatic, auxiliary, etc.) and detection methods (HPLC-MS/MS, GC-ICP-MS, etc.) for SePs/SePPs in plants. Their bioavailability and bioactivity, and the effect of processing are also included. Our review provides a comprehensive understanding and theoretical guidance for the utilization of selenium-enriched proteins/peptides.

The process of hypertension induced by high-salt diet: Association with interactions between intestinal mucosal microbiota, and chronic low-grade inflammation, end-organ damage

Inflammation and immunity play a major role in the development of hypertension, and a potential correlation between host mucosal immunity and inflammatory response regulation. We explored the changes of intestinal mucosal microbiota in hypertensive rats induced by high-salt diet and the potential link between the intestinal mucosal microbiota and inflammation in rats. Therefore, we used PacBio (Pacific Bioscience) SMRT sequencing technology to determine the structure of intestinal mucosal microbiota, used enzyme-linked immunosorbent assay (ELISA) to determined the proinflammatory cytokines and hormones associated with hypertension in serum, and used histopathology methods to observe the kidney and vascular structure. We performed a potential association analysis between intestinal mucosal characteristic bacteria and significantly different blood cytokines in hypertensive rats induced by high-salt. The results showed that the kidney and vascular structures of hypertensive rats induced by high salt were damaged, the serum concentration of necrosis factor-α (TNF-α), angiotensin II (AngII), interleukin-6 (IL-6), and interleukin-8 (IL-8) were significantly increased (p < 0.05), and the coefficient of immune organ spleen was significantly changed (p < 0.05), but there was no significant change in serum lipids (p > 0.05). From the perspective of gut microbiota, high-salt diet leads to significant changes in intestinal mucosal microbiota. Bifidobacterium animalis subsp. and Brachybacterium paraconglomeratum were the dominant differential bacteria in intestinal mucosal, with the AUC (area under curve) value of Bifidobacterium animalis subsp. and Brachybacterium paraconglomeratum were 1 and 0.875 according to ROC (receiver operating characteristic) analysis. Correlation analysis showed that Bifidobacterium animalis subsp. was correlated with IL-6, IL-8, TNF-α, and Ang II. Based on our results, we can speculated that high salt diet mediated chronic low-grade inflammation through inhibited the growth of Bifidobacterium animalis subsp. in intestinal mucosa and caused end-organ damage, which leads to hypertension.

Hypertension of liver-yang hyperactivity syndrome induced by a high salt diet by altering components of the gut microbiota associated with the glutamate/GABA-glutamine cycle

The gut microbiota and metabolites are closely related to hypertension; however, the changes in the composition of the gut microbiome and metabolites linking a high salt diet to elevated blood pressure are not established. In this study, traditional Chinese medicine (TCM) syndrome of hypertension caused by high salt had been diagnosed and the pathogenesis of hypertension was explored from the perspective of intestinal microecology. Rats in a high salt diet-induced hypertension group (CG) and normal group (CZ) were compared by 16S rRNA gene full-length sequencing and liquid chromatography and mass spectrometry to identify differences in the bacterial community structure, metabolites, and metabolic pathways. Hypertension induced by a high salt diet belongs to liver-Yang hyperactivity syndrome. Alpha and beta diversity as well as the composition of microbiota from the phylum to species levels differed substantially between the CG and CZ groups. In an analysis of differential metabolites in the intestines, a high salt diet mainly affected the metabolism of amino acids and their derivatives; in particular, γ-aminobutyric acid (GABA) was down-regulated and glutamic acid and its derivatives were up-regulated under a high salt diet. Based on a KEGG analysis, high salt intake mainly altered pathways related to GABA and the glutamate/glutamine metabolism, such as the GABAergic synapse pathway and glutamatergic synapse pathway. The correlation analysis of differential gut microbes and differential metabolites suggested that a high salt diet promoted hypertension via the inhibition of Clostridiaceae_1 growth and alterations in the GABA metabolic pathway, leading to increased blood pressure. These findings suggest that a high salt diet induces hypertension of liver-Yang hyperactivity syndrome by mediating the microbiota associated with the glutamate/GABA-glutamine metabolic cycle via the gut–brain axis.