Bifidobacterium breve and Bifidobacterium longum Attenuate Choline-Induced Plasma Trimethylamine N-Oxide Production by Modulating Gut Microbiota in Mice

Antiaging Effects of Human Fecal Transplants with Different Combinations of Bifidobacterium bifidum LTBB21J1 and Lactobacillus casei LTL1361 in d-Galactose-Induced Mice

The feces of healthy middle-aged and old people were first transplanted into d-galactose-induced aging mice to construct humanized aging mice with gut microbiota (FMTC) to confirm the antiaging effect of probiotics produced from centenarians. The mouse model was then treated with centenarian-derived Bifidobacterium bifidum (FMTL), Lactobacillus casei (FMTB), and their mixtures (FMTM), and young mice were used as the control. Compared with the FMTC group, the results demonstrated that the probiotics and their combinations alleviated neuronal damage, increased antioxidant capacity, decreased inflammation, and enhanced cognitive and memory functions in aging mice. In the gut microbiota, the relative abundance of Lactobacillus, Ligilactobacillus, and Akkermansia increased and that of Desulfovibrio and Colidextribacter decreased in the FMTM group compared with that in the FMTC group. The three probiotic groups displayed significant changes in 15 metabolites compared with the FMTC group, with 4 metabolites showing increased expression and 11 metabolites showing decreased expression. The groups were graded as Control > FMTM > FMTB > FMTL > FMTC using a newly developed comprehensive quantitative scoring system that thoroughly analyzed the various indicators of this study. The beneficial antiaging effects of probiotics derived from centenarians were quantitatively described using a novel perspective in this study; it is confirmed that both probiotics and their combinations exert antiaging effects, with the probiotic complex group exhibiting a larger effect.

Gut microbiota and risk of coronary heart disease: a two-sample Mendelian randomization study

Background

The relationship between gut microbiota composition and coronary heart disease (CHD) has been recently reported in several observational studies. However, the causal effect of gut microbiota on coronary heart disease is uncharted.

Objective

This study attempted to investigate the effect of gut microbiota on coronary heart disease by Mendelian randomization (MR) analysis.

Methods

Through the two-sample MR method, single-nucleotide polymorphisms relevant to gut microbiota were selected as instrument variables to evaluate the causal association between gut microbiota and the risk of CHD.

Results

According to the selection criteria of the inverse variance-weighted average method, Class Actinobacteria, Class Lentisphaeria, Family Clostridiales vadinBB60group, Genus Clostridium innocuum group, Genus Bifidobacterium, Genus Butyricicoccus, Genus Oxalobacter, Genus Turicibacter, and Order Victivallales, presented a suggestive association with coronary heart disease.

Conclusion

This two-sample Mendelian randomization study found that gut microbiota was causally associated with coronary heart disease. Further randomized controlled trials are needed to clarify the protective effect of probiotics on coronary heart disease and their specific protective mechanisms.

Recent advances on the Role of Gut Microbiota in the Development of Heart Failure by Mediating Immune Metabolism

The association between gut microbiota and the development of heart failure has become a research hotspot in recent years and the impact of gut microbiota on heart failure has attracted growing interest. From 2006 to 2021, the global research on gut microbiota and heart failure has gradually expanded, indicating a developed and promising research field. There were 40 countries, 196 institutions, and 257 authors involved in the publication on the relationship between gut microbiota and heart failure, respectively. In patients with heart failure, inadequate visceral perfusion leads to ischemia and intestinal edema, which compromise the gut barrier. This subsequently results in the translocation of bacteria and bacterial metabolites into the circulatory system and causes local and systemic inflammatory responses. The gastrointestinal tract contains the largest number of immune cells in the human body and gut microbiota play important roles in the immune system by promoting immune tolerance to symbiotic bacteria. Studies have shown that probiotics can act on gut microorganisms, thereby increasing choline metabolism and reducing plasma TMA and TMAO concentrations, thus inhibiting the development of heart failure. Meanwhile, probiotics induce the production of inflammatory suppressors to maintain gut immune stability and inhibit the progression of heart failure by reducing ventricular remodeling. Here, we review the current understanding of gut microbiota-driven immune dysfunction in experimental and clinical heart failure, as well as the therapeutic interventions that could be used to address these issues.

Safety and efficacy of adding postbiotics in infant formula: a systematic review and meta-analysis

Postbiotics, as emerging products, were added to infant formula, but their safety and efficacy are unclear. To clarify this issue, we wrote this meta-analysis. We searched PubMed, Embase, Web of Science and ProQuest from its establishment to February 2023. The review was registered on PROSPERO database (CRD42022352405). The effects of infant formula with and without postbiotics were compared, and the incidence of serious adverse events (SAEs), digestive symptoms, concentration of stool secretory immunoglobulin A (SIgA), and growth and development indexes were analyzed. Nine randomized controlled trials with 2065 participants were included. The addition of postbiotics to infant formula was found to increase the concentration of stool SIgA (P < 0.05) with very low certainty of evidence, without significantly impacting the incidence of SAEs, infantile colic, flatulence, diarrhea, vomiting, abdominal pain and gastrointestinal disorders, the daily weight gain, the total gain in body length and the daily head circumference gain (all P > 0.05). Adding postbiotics to the formula is safe for infants, which would not increase the incidence of SAEs, infantile colic, flatulence, diarrhea, vomiting, abdominal pain, and gastrointestinal disorders, and could increase the concentration of stool SIgA. IMPACT: Our study provides evidence that the addition of postbiotics to infant formula is safe but not effective. This is the first systematic review and meta-analysis of postbiotics. This study provides strong evidence for the safety of postbiotics and lays a foundation for related clinical trials.

Gut microbiota composition may be an indicator of erectile dysfunction

Erectile Dysfunction (ED) is considered a physical and mental illness. A variety of potential associations between gut microbiota and health or disease have been found. By comparing the gut microbiota of healthy controls and ED patients, our study investigated the relationship between ED and gut microbiota. The results revealed that the ED group exhibited a significantly higher relative abundance of Bacteroides, Fusobacterium, Lachnoclostridium, Escherichia-Shigella and Megamonas, while showing a significantly lower relative abundance of Bifidobacterium compared to the control group. The dysbiosis of gut microbiota played a role in the onset and progression of ED by influencing the gut barrier, cardiovascular system and mental health, which provided a novel perspective on understanding the pathophysiology of ED. What is more, we had identified several key gut microbiota. By combining 16S rRNA sequencing with machine learning techniques, we were able to uncover the significant value and impact of gut microbiota in the early detection of ED.

Bifidobacterium mechanisms of immune modulation and tolerance

Bifidobacterium is a widely distributed commensal bacterial genus that displays beneficial pro-homeostatic and anti-inflammatory immunomodulatory properties. Depletion or absence of Bifidobacterium in humans and model organisms is associated with autoimmune responses and impaired immune homeostasis. At the cellular level, Bifidobacterium upregulates suppressive regulatory T cells, maintains intestinal barrier function, modulates dendritic cell and macrophage activity, and dampens intestinal Th2 and Th17 programs. While there has been a large volume of literature characterizing the probiotic properties of various Bifidobacterial species, the likely multifactorial mechanisms underlying these effects remain elusive, in particular, its immune tolerogenic effect. However, recent work has shed light on Bifidobacterium surface structural polysaccharide and protein elements, as well as its metabolic products, as commensal mediators of immune homeostasis. This review aims to discuss several mechanisms Bifidobacterium utilizes for immune modulation as well as their indirect impact on the regulation of gut microbiome structure and function, from structural molecules to produced metabolites. These mechanisms are pertinent to an increasingly networked understanding of immune tolerance and homeostasis in health and disease.

Probiotics as potential treatments to reduce myocardial remodelling and heart failure via the gut-heart axis: State-of-the-art review

Probiotics are considered to represent important modulators of gastrointestinal health through increased colonization of beneficial bacteria thus altering the gut microflora. Although these beneficial effects of probiotics are now widely recognized, emerging evidence suggests that alterations in the gut microflora also affect numerous other organ systems including the heart through a process generally referred to as the gut-heart axis. Moreover, cardiac dysfunction such as that seen in heart failure can produce an imbalance in the gut flora, known as dysbiosis, thereby further contributing to cardiac remodelling and dysfunction. The latter occurs by the production of gut-derived pro-inflammatory and pro-remodelling factors which exacerbate cardiac pathology. One of the key contributors to gut-dependent cardiac pathology is trimethylamine N-oxide (TMAO), a choline and carnitine metabolic by-product first synthesized as trimethylamine which is then converted into TMAO by a hepatic flavin-containing monooxygenase. The production of TMAO is particularly evident with regular western diets containing high amounts of both choline and carnitine. Dietary probiotics have been shown to reduce myocardial remodelling and heart failure in animal models although the precise mechanisms for these effects are not completely understood. A large number of probiotics have been shown to possess a reduced capacity to synthesize gut-derived trimethylamine and therefore TMAO thereby suggesting that inhibition of TMAO is a factor mediating the beneficial cardiac effects of probiotics. However, other potential mechanisms may also be important contributing factors. Here, we discuss the potential benefit of probiotics as effective therapeutic tools for attenuating myocardial remodelling and heart failure.

The therapeutic value of bifidobacteria in cardiovascular disease

There has been an increase in cardiovascular morbidity and mortality over the past few decades, making cardiovascular disease (CVD) the leading cause of death worldwide. However, the pathogenesis of CVD is multi-factorial, complex, and not fully understood. The gut microbiome has long been recognized to play a critical role in maintaining the physiological and metabolic health of the host. Recent scientific advances have provided evidence that alterations in the gut microbiome and its metabolites have a profound influence on the development and progression of CVD. Among the trillions of microorganisms in the gut, bifidobacteria, which, interestingly, were found through the literature to play a key role not only in regulating gut microbiota function and metabolism, but also in reducing classical risk factors for CVD (e.g., obesity, hyperlipidemia, diabetes) by suppressing oxidative stress, improving immunomodulation, and correcting lipid, glucose, and cholesterol metabolism. This review explores the direct and indirect effects of bifidobacteria on the development of CVD and highlights its potential therapeutic value in hypertension, atherosclerosis, myocardial infarction, and heart failure. By describing the key role of Bifidobacterium in the link between gut microbiology and CVD, we aim to provide a theoretical basis for improving the subsequent clinical applications of Bifidobacterium and for the development of Bifidobacterium nutritional products.

Role of glycolysis in diabetic atherosclerosis

Diabetes mellitus is a kind of typical metabolic disorder characterized by elevated blood sugar levels. Atherosclerosis (AS) is one of the most common complications of diabetes. Modern lifestyles and trends that promote overconsumption and unhealthy practices have contributed to an increase in the annual incidence of diabetic AS worldwide, which has created a heavy burden on society. Several studies have shown the significant effects of glycolysis-related changes on the occurrence and development of diabetic AS, which may serve as novel thera-peutic targets for diabetic AS in the future. Glycolysis is an important metabolic pathway that generates energy in various cells of the blood vessel wall. In particular, it plays a vital role in the physiological and pathological activities of the three important cells, Endothelial cells, macrophages and vascular smooth muscle cells. There are lots of similar mechanisms underlying diabetic and common AS, the former is more complex. In this article, we describe the role and mechanism underlying glycolysis in diabetic AS, as well as the therapeutic targets, such as trained immunity, microRNAs, gut microbiota, and associated drugs, with the aim to provide some new perspectives and potentially feasible programs for the treatment of diabetic AS in the foreseeable future.

Targeting gut microbiota and immune crosstalk: potential mechanisms of natural products in the treatment of atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory reaction that primarily affects large and medium-sized arteries. It is a major cause of cardiovascular disease and peripheral arterial occlusive disease. The pathogenesis of AS involves specific structural and functional alterations in various populations of vascular cells at different stages of the disease. The immune response is involved throughout the entire developmental stage of AS, and targeting immune cells presents a promising avenue for its treatment. Over the past 2 decades, studies have shown that gut microbiota (GM) and its metabolites, such as trimethylamine-N-oxide, have a significant impact on the progression of AS. Interestingly, it has also been reported that there are complex mechanisms of action between GM and their metabolites, immune responses, and natural products that can have an impact on AS. GM and its metabolites regulate the functional expression of immune cells and have potential impacts on AS. Natural products have a wide range of health properties, and researchers are increasingly focusing on their role in AS. Now, there is compelling evidence that natural products provide an alternative approach to improving immune function in the AS microenvironment by modulating the GM. Natural product metabolites such as resveratrol, berberine, curcumin, and quercetin may improve the intestinal microenvironment by modulating the relative abundance of GM, which in turn influences the accumulation of GM metabolites. Natural products can delay the progression of AS by regulating the metabolism of GM, inhibiting the migration of monocytes and macrophages, promoting the polarization of the M2 phenotype of macrophages, down-regulating the level of inflammatory factors, regulating the balance of Treg/Th17, and inhibiting the formation of foam cells. Based on the above, we describe recent advances in the use of natural products that target GM and immune cells crosstalk to treat AS, which may bring some insights to guide the treatment of AS.

Alleviation of Limosilactobacillus reuteri in polycystic ovary syndrome protects against circadian dysrhythmia-induced dyslipidemia via capric acid and GALR1 signaling

Knowledge gaps that limit the development of therapies for polycystic ovary syndrome (PCOS) concern various environmental factors that impact clinical characteristics. Circadian dysrhythmia contributes to glycometabolic and reproductive hallmarks of PCOS. Here, we illustrated the amelioration of Limosilactobacillus reuteri (L. reuteri) on biorhythm disorder-ignited dyslipidemia of PCOS via a microbiota-metabolite-liver axis. A rat model of long-term (8 weeks) darkness treatment was used to mimic circadian dysrhythmia-induced PCOS. Hepatic transcriptomics certified by in vitro experiments demonstrated that increased hepatic galanin receptor 1 (GALR1) due to darkness exposure functioned as a critical upstream factor in the phosphoinositide 3-kinase (PI3K)/protein kinase B pathway to suppress nuclear receptors subfamily 1, group D, member 1 (NR1D1) and promoted sterol regulatory element binding protein 1 (SREBP1), inducing lipid accumulation in the liver. Further investigations figured out a restructured microbiome-metabolome network following L. reuteri administration to protect darkness rats against dyslipidemia. Notably, L. reuteri intervention resulted in the decrease of Clostridium sensu stricto 1 and Ruminococcaceae UCG-010 as well as gut microbiota-derived metabolite capric acid, which could further inhibit GALR1-NR1D1-SREBP1 pathway in the liver. In addition, GALR antagonist M40 reproduced similar ameliorative effects as L. reuteri to protect against dyslipidemia. While exogenous treatment of capric acid restrained the protective effects of L. reuteri in circadian disruption-induced PCOS through inhibiting GALR1-dependent hepatic lipid metabolism. These findings purport that L. reuteri could serve for circadian disruption-associated dyslipidemia. Manipulation of L. reuteri-capric acid-GALR1 axis paves way for clinical therapeutic strategies to prevent biorhythm disorder-ignited dyslipidemia in PCOS women.

New insight into gut microbiota and their metabolites in ischemic stroke: A promising therapeutic target

The gut-brain axis has been shown to play a vital role in the prognosis and recovery of ischemic stroke (IS), which is associated with gut microbiota dysfunction and changes in the gastrointestinal system and epithelial barrier integrity. In turn, gut microbiota and its derived metabolites can influence stroke outcomes. In this review, we first describe the relationship between IS (clinical and experimental IS) and the gut microbiota. Second, we summarize the role and specific mechanisms of microbiota-derived metabolites in IS. Further, we discuss the roles of natural medicines targeting the gut microbiota. Finally, the potential use of the gut microbiota and derived metabolites as a promising therapeutic opportunity for stroke prevention, diagnosis, and treatment is explored.

Ginger essential oil and citral ameliorates atherosclerosis in ApoE-/- mice by modulating trimethylamine-N-oxide and gut microbiota

Recently, the role of the gut microbiota in diseases, including cardiovascular disease (CVD), has gained considerable research attention. Trimethylamine-N-oxide (TMAO), which is formed during ʟ-carnitine metabolism, promotes the formation of atherosclerotic plaques, causing thrombosis. Here, we elucidated the anti-atherosclerotic effect and mechanism of ginger (Zingiber officinale Roscoe) essential oil (GEO) and its bioactive compound citral in Gubra Amylin NASH (GAN) diet with ʟ-carnitine-induced atherosclerosis female ApoE^-/- mice. Treatment with GEO at both low and high doses and citral inhibited the formation of aortic atherosclerotic lesions, improved plasma lipid profile, reduced blood sugar, improved insulin resistance, decreased plasma TMAO levels, and inhibited plasma inflammatory cytokines, especially interleukin-1β. Additionally, GEO and citral treatment modulated gut microbiota diversity and composition by increasing the abundance of beneficial microbes and decreasing the abundance of CVD-related microbes. Overall, these results showed that GEO and citral may serve as potential dietary supplements for CVD prevention by improving gut microbiota dysbiosis.

Characterization of gut microbiota in adults with coronary atherosclerosis

Background

Cardiovascular disease, which is mainly caused by coronary atherosclerosis, is one of the leading causes of death and disability worldwide. Gut microbiota likely play an important role in coronary atherosclerosis. This study aims to investigate the microbiota profile of adults with coronary atherosclerosis to provide a theoretical basis for future research.

Methods

Fecal samples were collected from 35 adult patients diagnosed with coronary atherosclerosis and 32 healthy adults in Nanjing, China, and the V3-V4 region of 16S rDNA genes was sequenced using high-throughput sequencing. Differences in alpha diversity, beta diversity, and gut microbiota composition between the two groups were then compared.

Results

A beta diversity analysis revealed significant differences between adults with coronary atherosclerosis and controls, but there was no statistical difference in alpha diversity between the two groups. There were also differences in the composition of the gut microbiota between the two groups. The genera, Megamonas, Streptococcus, Veillonella, Ruminococcus_torques_group, Prevotella_2, Tyzzerella_4, were identified as potential biomarkers for coronary atherosclerosis.

Conclusion

There are some differences in the gut microbiota of adults with coronary atherosclerosis compared to healthy adults. The insights from this study could be used to explore microbiome-based mechanisms for coronary atherosclerosis.

Effects of long-term regular oral aspirin combined with atorvastatin to prevent ischemic stroke on human gut microbiota

PURPOSE

Every year, there is a large number of people take aspirin and atorvastatin to prevent ischemic stroke, but the effect of these drugs on gut microbiota remains unknown. We aimed to examine the effects of long-term regular oral aspirin with atorvastatin to prevent ischemic stroke on human gut microbiota.

METHODS

A cross-sectional study of 20 participants with the drugs over one year and the other 20 gender- and age-matching participants without medication were recruited from the Affiliated Hospital of Guizhou Medical University. The medication habits and dietary information were obtained using a questionnaire. Fecal samples collected from all participants were subjected to 16S rRNA sequencing of the microbiome. The datasets were analyzed using bioinformatics approaches.

RESULTS

The Alpha diversity showed that compared with controls, medication participants had lower ACE and Chao1 index, while no difference in the Shannon index and Simpson index. The Beta diversity analysis revealed significant shifts in the taxonomic compositions of the two groups. Linear discriminant analysis effect size (LEfSe) analysis combined with receiver operating characteristic (ROC) curves revealed the marker bacteria associated with taking medication were g_Parabacteroides（AUC = 0.855）, g_Bifidobacterium（AUC = 0.815）, s_Bifidobacterium_longum_subsp（AUC = 0.8075）, and with no taking medication was g_Prevotella_9（AUC = 0.76）.

CONCLUSIONS

Our findings indicated that long-term regular oral aspirin and atorvastatin modulate the human gut microbiota. Taking these drugs may affect the preventive effect of ischemic stroke by changing the abundance of specific gut microbiota.

Gut Failure: A Review of the Pathophysiology and Therapeutic Potentials in the Gut-Heart Axis

Despite considerable advances in the field, heart failure (HF) still poses a significant disease burden among affected individuals since it continues to cause high morbidity and mortality rates. Inflammation is considered to play a key role in disease progression, but the exact underlying pathophysiological mechanisms involved have not yet been fully elucidated. The gut, as a potential source of inflammation, could feasibly explain the state of low-grade inflammation seen in patients with chronic HF. Several derangements in the composition of the microbiota population, coupled with an imbalance between favorable and harmful metabolites and followed by gut barrier disruption and eventually bacterial translocation, could contribute to cardiac dysfunction and aggravate HF. On the other hand, HF-associated congestion and hypoperfusion alters intestinal function, thereby creating a vicious cycle. Based on this evidence, novel pharmaceutical agents have been developed and their potential therapeutic use has been tested in both animal and human subjects. The ultimate goal in these efforts is to reverse the aforementioned intestinal derangements and block the inflammation cascade. This review summarizes the gut-related causative pathways implicated in HF pathophysiology, as well as the associated therapeutic interventions described in the literature.

The Role of the Gut Microbiome and Trimethylamine Oxide in Atherosclerosis and Age-Related Disease

The gut microbiome plays a major role in human health, and gut microbial imbalance or dysbiosis is associated with disease development. Modulation in the gut microbiome can be used to treat or prevent different diseases. Gut dysbiosis increases with aging, and it has been associated with the impairment of gut barrier function leading to the leakage of harmful metabolites such as trimethylamine (TMA). TMA is a gut metabolite resulting from dietary amines that originate from animal-based foods. TMA enters the portal circulation and is oxidized by the hepatic enzyme into trimethylamine oxide (TMAO). Increased TMAO levels have been reported in elderly people. High TMAO levels are linked to peripheral artery disease (PAD), endothelial senescence, and vascular aging. Emerging evidence showed the beneficial role of probiotics and prebiotics in the management of several atherogenic risk factors through the remodeling of the gut microbiota, thus leading to a reduction in TMAO levels and atherosclerotic lesions. Despite the promising outcomes in different studies, the definite mechanisms of gut dysbiosis and microbiota-derived TMAO involved in atherosclerosis remain not fully understood. More studies are still required to focus on the molecular mechanisms and precise treatments targeting gut microbiota and leading to atheroprotective effects.

Alteration of the gut microbiota and metabolite phenylacetylglutamine in patients with severe chronic heart failure

Chronic Heart Failure (CHF) is the end result of nearly all cardiovascular disease and is the leading cause of deaths worldwide. Studies have demonstrated that intestinal flora has a close relationship with the development of Cardiovascular Disease (CVD) and plays a vital role in the disease evolution process. Phenylacetylglutamine (PAGln) a metabolite of the intestinal flora, is one of the common chronic kidney disease toxins. Its concentrations in plasma were higher in patients with major adverse cardiovascular events (MACE) however, its variation in patients with various degrees of CHF has rarely been reported. Therefore, we collected stool and plasma samples from 22 healthy controls, 29 patients with NYHA Class III and 29 patients with NYHA Class IV CHF (NYHA stands for New York Heart Association) from the Department of Cardiology of Shanghai Fengxian District Central Hospital. Next, we analyzed these samples by performing bacterial 16S ribosomal RNA gene sequencing and liquid chromatography tandem mass spectrometry. The result shows: The Chao 1 index was significantly lower in both NYHA class III and NYHA class IV than it was in the control group. The beta diversity was substantially dissimilar across the three groups. The linear discriminant analysis effect size analysis (LEfSe) showed that the bacterial species with the largest differences were Lachnospiraceae in control group, Enterobacteriaceae in NYHA class III, and Escherichia in NYHA class IV. The concentration of PAGln was significantly different between CHF and control groups and increased with the severity of heart failure. Finally, the correlation analysis represented that Parabacteroides and Bacteroides were negatively correlated to brain natriuretic peptide (BNP) and PAGln; Romboutsia and Blautia adversely associated with PAGln; Klebsiella was positively interrelated with BNP; Escherichia-Shigella was positively correlated with PAGln and BNP; Alistipes was contrasted with BNP; and Parabacteroides was negatively correlated with the left ventricular end-diastolic diameter (LVEDD). This study presented that the intestinal flora and its metabolite PAGln were altered with different grades of CHF and illustrated the effects of the gut flora and its metabolite on CHF.

Impact of Bifidobacterium adolescentis in patients with abdominal aortic aneurysm: a cross-sectional study

The relationships between various diseases and the human gut microbiota (GM) have been revealed. However, the relationships between the human abdominal aortic aneurysm (AAA) and GM remains unknown. The aim of this cross-sectional study was to clarify the association between the human AAA and GM. Stool samples from 30 consecutive patients with AAA before aneurysm repair and those of 30 controls without vascular diseases were analyzed by 16S rRNA gene (V3-4) sequencing using an Illumina MiSeq system and QIIME 2. There was no significant difference in age (75 vs. 75 years) or gender (80% vs. 87% males) between the groups. No significant difference in GM composition was observed in principal coordinate analysis between the two groups, whereas the AAA group showed a significantly lower abundance of Bifidobacterium adolescentis (p<0.01) at the species level than the controls. This study demonstrated that the abundance of B. adolescentis decreased in patients with AAA. This is the first study to show the characteristics of the GM in patients with AAA. Studies are needed to reveal if causal relationships exists between the human AAA and GM.

Targeting Trimethylamine N-Oxide: A New Therapeutic Strategy for Alleviating Atherosclerosis

Atherosclerosis (AS) is one of the most common cardiovascular diseases (CVDs), and there is currently no effective drug to reverse its pathogenesis. Trimethylamine N-oxide (TMAO) is a metabolite of the gut flora with the potential to act as a new risk factor for CVD. Many studies have shown that TMAO is involved in the occurrence and development of atherosclerotic diseases through various mechanisms; however, the targeted therapy for TMAO remains controversial. This article summarizes the vital progress made in relation to evaluations on TMAO and AS in recent years and highlights novel probable approaches for the prevention and treatment of AS.