Conjugated bile acids are nutritionally re-programmable antihypertensive metabolites

"Gut Microbiota as a Therapeutic Target for Hypertension: Challenges and Insights for Future Clinical Applications" "Gut Microbiota and Hypertension Therapy"

PURPOSE OF REVIEW

Systemic hypertension is a major risk factor for cardiovascular disease and remains challenging to manage despite the widespread use of antihypertensive medications and lifestyle modifications. This review explores the role of gut microbiota in hypertension development and regulation, highlighting key mechanisms such as inflammation, gut-brain axis modulation, and bioactive metabolite production. We also assess the potential of microbiota-targeted therapies for hypertension management.

RECENT FINDINGS

Emerging evidence indicates that microbial dysbiosis, high-salt diets, and gut-derived metabolites such as short-chain fatty acids (SCFAs) and bile acids significantly influence blood pressure regulation. Preclinical and early clinical studies suggest that interventions targeting gut microbiota, including probiotics, prebiotics, synbiotics, fecal microbiota transplantation (FMT), and dietary modifications, may help modulate hypertension. However, variability in gut microbiota composition among individuals and limited human trial data pose challenges to translating these findings into clinical practice. While microbiota-based therapies show promise for hypertension management, further research is needed to establish their efficacy and long-term effects. Large-scale, standardized clinical trials are crucial for understanding the therapeutic potential and limitations of gut microbiota interventions. A deeper understanding of the gut-hypertension axis could lead to novel, personalized treatment strategies for hypertension.

Recent advances on immunity and hypertension: the new cells on the kidney block

Over the past 50 years, the contribution of the immune system has been identified in the development of hypertension and renal injury. Both human and experimental animal models of hypertension have demonstrated that innate and adaptive immune cells, along with their cytokines and chemokines, modulate blood pressure fluctuations and end organ renal damage. Numerous cell types of the innate immune system, specifically monocytes, macrophages, and dendritic cells, present antigenic peptides to T cells, promoting inflammation and the elevation of blood pressure. These T cells and other adaptive immune cells migrate to vascular and tubular cells of the kidney and promote end-organ fibrosis, damage, and ultimately hypertensive injury. Through the development of high-throughput screening, novel renal and immune cell subsets have been identified as possible contributors and regulators of renal injury and hypertension. In this review, we will consider classical immunological cells and their contribution to renal inflammation, and novel cell subsets, including renal stromal cells, that could potentially shed new light on renal injury and hypertension. Finally, we will discuss how interorgan inflammation contributes to the development of hypertension and hypertension-related multiorgan damage, and explore the clinical implications of the immunological components of renal injury and hypertension.

Bile Acid Metabolism Analysis Provides Insights into Vascular Endothelial Injury in Salt-Sensitive Hypertensive Rats

As an unhealthy dietary habit, a high-salt diet can affect the body's endocrine system and metabolic processes. As one of the most important metabolites, bile acids can prevent atherosclerosis and reduce the risk of developing cardiovascular diseases. Therefore, in the present study, we aimed to reveal the bile acid metabolism changes in salt-sensitive hypertension-induced vascular endothelial injury. The model was established using a high-salt diet, and the success of this procedure was confirmed by detecting the levels of the blood pressure, vascular regulatory factors, and inflammatory factors. An evaluation of the histological sections of arterial blood vessels and kidneys confirmed the pathological processes in these tissues of experimental rats. Bile acid metabolism analysis was performed to identify differential bile acids between the low-salt diet group and the high-salt diet group. The results indicated that the high-salt diet led to a significant increase in blood pressure and the levels of endothelin-1 (ET-1) and tumor necrosis factor-α (TNF-α). The high-salt diet causes disorders in bile acid metabolism. The levels of four differential bile acids (glycocholic acid, taurolithocholic acid, tauroursodeoxycholic acid, and glycolithocholic acid) significantly increased in the high-salt group. Further correlation analysis indicated that the levels of ET-1 and TNF-α were positively correlated with these differential bile acid levels. This study provides new evidence for salt-sensitive cardiovascular diseases and metabolic changes caused by a high-salt diet in rats.

Taurocholic acid ameliorates hypertension through the activation of TGR5 in the hypothalamic paraventricular nucleus

Diets rich in taurine can increase the production of taurine-conjugated bile acids, which are known to exert antihypertensive effects. Despite their benefits to the heart, kidney and arteries, their role in the central nervous system during the antihypertensive process remains unclear. Since hypothalamic paraventricular nucleus (PVN) plays a key role in blood pressure regulation, we aimed to investigate the function of bile acids in the PVN. The concentration of bile acids in the PVN of spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto rats (WKY) fed with normal chow was measured using LC-MS/MS, which identified taurocholic acid (TCA) as the most down-regulated bile acid. To fully understand the mechanism of TCA's functions in the PVN, bi-lateral PVN micro-infusion of TCA was carried out. TCA treatment in the PVN led to a significant reduction in the blood pressure of SHRs, with decreased plasma levels of norepinephrine and improved morphology of cardiomyocytes. It also decreased the number of c-fos+ neurons, reduced the inflammatory response, and suppressed oxidative stress in the PVN of the SHRs. Most importantly, the TGR5 receptors in neurons and microglia were activated. PVN infusion of SBI-115, a TGR5 specific antagonist, was able to counteract with TCA in the blood pressure regulation of SHRs. In conclusion, TCA supplementation in the PVN of SHRs can activate TGR5 in neurons and microglia, reduce the inflammatory response and oxidative stress, suppress activated neurons, and attenuate hypertension.

Inferring Bladder Cancer Evolution from Mucosal field Effects by Whole-Organ Spatial Mutational, Proteomic, and Metabolomic Mapping

Multi-platform mutational, proteomic, and metabolomic spatial mapping was used on the whole-organ scale to identify the molecular evolution of bladder cancer from mucosal field effects. We identified complex proteomic and metabolomic dysregulations in microscopically normal areas of bladder mucosa adjacent to dysplasia and carcinoma in situ. The mutational landscape developed in a background of complex defects of protein homeostasis which included dysregulated nucleocytoplasmic transport, splicesome, ribosome biogenesis, and peroxisome. These changes were combined with altered urothelial differentiation which involved lipid metabolism and protein degradations controlled by PPAR. The complex alterations of proteome were accompanied by dysregulation of gluco-lipid energy-related metabolism. The analysis of mutational landscape identified three types of mutations based on their geographic distribution and variant allele frequencies. The most common were low frequency α mutations restricted to individual mucosal samples. The two other groups of mutations were associated with clonal expansion. The first of this group referred to as β mutations occurred at low frequencies across the mucosa. The second of this group called γ mutations increased in frequency with disease progression. Modeling of the mutations revealed that carcinogenesis may span nearly 30 years and can be divided into dormant and progressive phases. The α mutations developed gradually in the dormant phase. The progressive phase lasted approximately five years and was signified by the advent of β mutations, but it was driven by γ mutations which developed during the last 2-3 years of disease progression to invasive cancer. Our study indicates that the understanding of complex alterations involving mucosal microenvironment initiating bladder carcinogenesis can be inferred from the multi-platform whole-organ mapping.

Untapped potential of gut microbiome for hypertension management

The gut microbiota has been shown to be associated with a range of illnesses and disorders, including hypertension, which is recognized as the primary factor contributing to the development of serious cardiovascular diseases. In this review, we conducted a comprehensive analysis of the progression of the research domain pertaining to gut microbiota and hypertension. Our primary emphasis was on the interplay between gut microbiota and blood pressure that are mediated by host and gut microbiota-derived metabolites. Additionally, we elaborate the reciprocal communication between gut microbiota and antihypertensive drugs, and its influence on the blood pressure of the host. The field of computer science has seen rapid progress with its great potential in the application in biomedical sciences, we prompt an exploration of the use of microbiome databases and artificial intelligence in the realm of high blood pressure prediction and prevention. We propose the use of gut microbiota as potential biomarkers in the context of hypertension prevention and therapy.

Lingguizhugan Decoction Improved Obesity by Modulating the Gut Microbiota and its Metabolites in Mice

BACKGROUND

The global obese population is rapidly increasing, urgently requiring the development of effective and safe weight-loss medications. The classic Chinese medicine formulation Lingguizhugan Decoction has exerted a significant anti-obesity effect. However, the underlying mechanism is still unclear.

OBJECTIVE

This study aimed to explore the mechanism of LGZGD in the treatment of obesity based on the gut microbiota and its metabolites.

METHODS

Three different dosages of LGZGD were gavaged to ob/ob mice for 8 weeks. Body mass and visceral fat mass were evaluated. Additionally, the changes in gut microbiota, fecal and plasma metabolites in mice after LGZGD treatment were analyzed by metagenomics and non-targeted metabolomics.

RESULTS

The results demonstrated a significant anti-obesity effect of LGZGD treatment in ob/ob mice. Furthermore, the metagenomic analysis revealed that LGZGD reduced the ratio of Firmicutes / Bacteroidetes (F to B) in the gut, restored gut microbiota diversity, and identified 3 enriched KEGG pathways, including energy metabolism, lipid metabolism, and energy production and conversion pathways. Based on non-targeted metabolomics analysis, 20 key metabolites in the feces and 30 key metabolites in the plasma responding to LGZGD treatment were identified, and the levels of Eicosapentaenoic acid (EPA) and Myristoleic acid (MA) might be the metabolites related to gut microbiota after LGZGD treatment. Their biological functions were mainly related to the metabolism pathway.

CONCLUSIONS

These findings suggested that LGZGD had therapeutic potential for obesity. The mechanism of LGZGD alleviating obesity was associated with improving dysbiosis of the gut microbiota. LDZGD affected gut microbiota-derived metabolites of EPA and MA and may act on energy metabolism pathways.

Flattening the biological age curve by improving metabolic health: to taurine or not to taurine, that' s the question

The aging population is an important issue around the world especially in developed countries. Although medical advances have substantially extended life span, the same cannot be said for the duration of health span. We are seeing increasing numbers of elderly people who are frail and/or have multiple chronic conditions; all of these can affect the quality of life of the elderly population as well as increase the burden on the healthcare system. Aging is mechanistically related to common medical conditions such as diabetes mellitus, ischemic heart disease, cognitive decline, and frailty. A recently accepted concept termed 'Accelerated Biological Aging' can be diagnosed when a person's biological age-as measured by biomarkers of DNA methylation-is older than their corresponding chronological age. Taurine, a conditionally essential amino acid, has received much attention in the past few years. A substantial number of animal studies have provided a strong scientific foundation suggesting that this amino acid can improve cellular and metabolic health, including blood glucose control, so much that it has been labelled one of the 'longevity amino acids'. In this review article, we propose the rationale that an adequately powered randomized-controlled-trial (RCT) is needed to confirm whether taurine can meaningfully improve metabolic and microbiome health, and biological age. This trial should incorporate certain elements in order to provide the much-needed evidence to guide doctors, and also the community at large, to determine whether this promising and inexpensive amino acid is useful in improving human metabolic health.

Metabolipidomic Analysis in Patients with Obstructive Sleep Apnea Discloses a Circulating Metabotype of Non-Dipping Blood Pressure

A non-dipping blood pressure (BP) pattern, which is frequently present in patients with obstructive sleep apnea (OSA), confers high cardiovascular risk. The mechanisms connecting these two conditions remain unclear. In the present study we performed a comprehensive analysis of the blood metabolipidome that aims to provide new insights into the molecular link between OSA and the dysregulation of circadian BP rhythmicity. This was an observational prospective longitudinal study involving adults with suspected OSA who were subjected to full polysomnography (PSG). Patients with an apnea-hypopnea index ≥ 5 events/h were included. Fasting plasma samples were obtained the morning after PSG. Based on the dipping ratio (DR; ratio of night/day BP values) measured via 24 h ambulatory BP monitoring, two groups were established: dippers (DR ≤ 0.9) and non-dippers (DR > 0.9). Treatment recommendations for OSA followed the clinical guidelines. Untargeted metabolomic and lipidomic analyses were performed in plasma samples via liquid chromatography-tandem mass spectrometry. Non-dipper patients represented 53.7% of the cohort (88/164 patients). A set of 31 metabolic species and 13 lipidic species were differentially detected between OSA patients who present a physiologic nocturnal BP decrease and those with abnormal BP dipping. Among the 44 differentially abundant plasma compounds, 25 were putatively identified, notably glycerophospholipids, glycolipids, sterols, and fatty acid derivates. Multivariate analysis defined a specific metabotype of non-dipping BP, which showed a significant dose-response relationship with PSG parameters of OSA severity, and with BP dipping changes after 6 months of OSA treatment with continuous positive airway pressure (CPAP). Bioinformatic analyses revealed that the identified metabolipidomic profile was found to be implicated in multiple systemic biological pathways, with potential physiopathologic implications for the circadian control of BP among individuals with OSA.

Microbiota-associated mechanisms underlying sexual dimorphism in hypertension

Consistent research over the last 20 years has shown that there are clear sex differences in the pathogenesis of hypertension, the leading risk factor for the development of cardiovascular diseases. More recently, there is evidence in both humans and experimental animal models that causally implicates the gut microbiota in hypertension. It therefore follows that sex differences in the gut microbiota may mediate the extent of disease between sexes. This new field is rapidly changing and advancing, and the purpose of this review is to cover the most up-to-date evidence regarding the sexual dimorphism of the gut microbiota and its potential influence on the differential manifestation of hypertension in males versus females. Emphasis will be placed on the mechanisms thought to contribute to these sex differences in both the gut microbiota and hypertension, including sex steroid hormones, gut-derived metabolites, the immune system, and pregnancy.