Contribution of Trimethylamine N-Oxide (TMAO) to Chronic Inflammatory and Degenerative Diseases

A Case-Control Study of Dietary Choline Intake and Risk of Colorectal Cancer Modified by Dietary B-Vitamin Intake

BACKGROUND/OBJECTIVES

The incidence of colorectal cancer (CRC) is rising, and Western diets high in red and processed meats may be contributing. It is important to identify dietary nutrients that increase CRC risk and perhaps interventions that may modulate such risk. The relationship between dietary choline intake and CRC is still unclear. We hypothesize that high dietary choline intake is associated with greater CRC risk, and B vitamin supplementation may modify this risk.

METHODS

In this case-control study, we collected demographic and dietary data using the validated National Cancer Institute CRC Risk Assessment Tool and Dietary Health Questionnaire III and analyzed colonoscopy outcomes. Logistic regression and stratified analyses were performed to calculate adjusted odds ratios and evaluate for effect modification.

RESULTS

Of 52 total patients, 21 had a normal colonoscopy result, and 31 were found to either have benign polyps or CRC. The average dietary choline intake was 207 mg/day in the normal group and 297 mg/day in the abnormal outcome group. A doubling in dietary choline intake was significantly associated with increased odds of polyps or CRC (OR 25.32, 95% CI 1.95-327.94). When stratified by vitamin B levels, the effect modification was difficult to confidently quantify due to the limited sample size.

CONCLUSIONS

Our findings suggest that higher dietary choline intake may be associated with an increased risk of CRC and its precursors, such as polyps. Although the potential modifying role of B vitamins was inconclusive, this study underscores the need for larger-scale research to further explore these associations and to assess the potential of dietary interventions in reducing CRC risk.

Correlation of Triethylamine N-oxide (TMAO), LPS, and TNF-Alpha Levels With Clinical Features of the Disease in Patients With and Without Septic Shock Infected With COVID-19 Virus

BACKGROUND

Inflammation is a response of the immune system to protect the body against various diseases or injuries. Serum trimethylamine N-oxide (TMAO) levels may vary depending on age, gender, habits, comorbidities, and microbiota.

AIMS

In this study, we investigated whether TMAO levels have diagnostic significance and their potential as a marker in the early diagnosis of the disease. Another aim of the research was to identify changes in TMAO levels as a reflection of the deterioration in the microflora, and IL-6, IL-10, IL-1β, TNF-alpha, and LPS levels in patient groups. Then, we recognized relationships between these parameters in patients infected with COVID-19 without septic shock and with COVID-19 who were without transmission of COVID-19 in septic shock.

STUDY DESIGN

A total of 160 patients were investigated, including 40 patients infected with COVID-19 without septic contact, 40 patients with COVID-19 positive septic shock, 40 patients with COVID-19 negative septic shock, and 40 healthy individuals as the control group.

RESULTS

TNF-α and IL-1β levels were significantly lower (P < 0.001) and IL-6 and IL-10 levels were significantly higher (P < 0.001) in patient groups than in control groups. IL-1β showed a significant decrease, especially in the groups infected with COVID-19. Although IL-6, increased even more in the groups infected with COVID-19.

CONCLUSIONS

LPS level was remarkably high in the sepsis group infected with COVID-19 compared to the other groups. TMAO level was significantly higher (P < 0.001) in the sepsis group. Therefore, TMAO is a potential biomarker in sepsis and septic shock.

Primary Prevention Strategy for Non-Communicable Diseases (NCDs) and Their Risk Factors: The Role of Intestinal Microbiota

Non-communicable diseases (NCDs) are the leading cause of morbidity and mortality worldwide. These conditions have numerous health consequences and significantly impact patients' lifestyles. Effective long-term treatment is essential since NCDs are irreversible. Therefore, primary healthcare must be both exclusive and of the highest quality, ensuring comprehensive care. The primary goal should be to improve quality of life with a focus on patients, families, and communities, as most of these diseases can be prevented and controlled, although not cured. Several factors have been linked to individual health, including social, cultural, and economic aspects, lifestyle, and certain environmental factors, including work, that can have positive or negative effects. More of these variables may contribute to the onset of NCDs, which are defined by their chronic nature, propensity for prolongation, and generally slow rate of progression. Examples of NCDs include hypertension, type 2 diabetes (T2D), dyslipidemia, and fatty liver disease linked to metabolic dysfunction. The onset of these diseases has been associated with an imbalance in certain microbial niches, such as the gut, which hosts billions of microorganisms performing multiple metabolic functions, such as the production of metabolites like bile acids (BAs), short-chain fatty acids (SCFAs), and trimethylamine N-oxide (TMAO). Therefore, lifestyle changes and personal habits can significantly impact the gut microbiota (GM), potentially preventing chronic diseases associated with metabolism. NCDs are highly prevalent worldwide, prompting increased attention to strategies for modifying the intestinal microbiota (IM). Approaches such as probiotics, prebiotics, synbiotics, and fecal transplantation (FMT) have demonstrated improvements in the quality of life for individuals with these conditions. Additionally, lifestyle changes and the adoption of healthy habits can significantly impact IM and may help prevent chronic diseases related to metabolism. Therefore, the main aim of this review is to analyze and understand the importance of microbiota intervention in the prevention of non-communicable diseases. R3:A1.

Gut microbiome and inflammation in cardiovascular drug response: trends in therapeutic success and commercial focus

The intricate Gut microbiome is evolving as an important system and is hypothesized to be a "metabolic organ" within the host. Alterations in Gut microbiota and inflammation associated with several diseases play a crucial role in drug transformation through microbiota-host co-metabolism, modified pharmacokinetic and pharmacodynamics profiles, and may result in the formation of toxic metabolites with interference in drug response. In recent studies, a large number of drugs are reported that are co-metabolized by the host and the Gut microbial enzymes. we summarize the direct and indirect involvement of Gut microbiome promotion or inhibition of cardiovascular diseases, mechanisms on bioavailability, and therapeutic outcomes of cardiovascular drugs, particularly pharmacokinetics and pharmacodynamics profiles in light of AUC, Tmax, Cmax, and bioavailability and drug transportation via immune cells, inter-individual variations in intestinal microbial taxonomy, influence of drugs on diversity and richness of microflora, high lightening limitations and significance of in personalized medicine. Recent advances in target-drug delivery by nanoparticles with limitations and challenges in application are discussed. The cross-talk between Gut microbiota and cardiovascular drugs signifies a better understanding and rationale for targeting the Gut microbiota to improve the therapeutic outcome for cardiovascular diseases, with present-day limitations.

The gut microbiota metabolite trimethylamine-N-oxide in children with β-thalassemia: potential implication for iron-induced renal tubular dysfunction

BACKGROUND

Renal tubular dysfunction is common in transfusion-dependent β thalassemia (β-TM). Iron overload, chronic anemia, and hypoxia are precipitating factors for renal insult. However, gut microbiota engagement in the renal insult has not been explored. Our work aimed to assess the potential link between iron overload, gut leakage/dysbiosis, and kidney dysfunction in these children.

METHODS

We enrolled 40 children with β-TM and 40 healthy controls. Gut leakage/dysbiosis biomarkers (trimethylamine-N-oxide [TMAO] and fecal short-chain fatty acids [SCFAs]), oxidative stress and inflammatory biomarkers, TMAO-regulated proteins such as serum sirtuin 1 (S.SIRT1) and serum high mobility box group-1 (S.HMGB1), and tubular dysfunction biomarkers were assessed. Correlations and regression analysis were performed to assess the relation between different parameters.

RESULTS

Iron overload, redox imbalance, and generalized inflammation were evident in children with β-TM. Renal tubular dysfunction biomarkers and S.TMAO were significantly elevated in the patient group. Furthermore, fecal SCFAs were significantly lower with upregulation of the investigated genes in the patient group. The correlation studies affirmed the close relationship between circulating ferritin, TMAO, and renal dysfunction and strongly implicated SIRT1/HMGB1 axis in TMAO action.

CONCLUSIONS

Gut dysbiosis may have a role in the pathogenesis of renal injury in children with β-TM.

IMPACT

Renal tubular dysfunction is a prominent health issue in β thalassemia major (β-TM). Iron overload, chronic anemia, and hypoxia are known precipitating factors. However, gut microbiota engagement in renal insult in these patients has not yet been explored. We aimed to assess potential link between iron overload, gut leakage/dysbiosis, and kidney dysfunction in β-TM children and to highlight the SIRT1/HMGB1 axis, a signal motivated by the gut microbiota-dependent metabolite trimethylamine-N-oxide (TMAO), involvement in such insults. We found that gut leakage/dysbiosis may have a role in kidney dysfunction in β-TM children by exacerbating the iron-motivated oxidative stress, inflammation, ferroptosis, and modulating SIRT1/HMGB1 axis.

Unveiling the causal effects of gut microbiome on trimethylamine N-oxide: evidence from Mendelian randomization

Objective

The relationship between gut microbiome and trimethylamine oxide (TMAO) has not been fully elucidated. We aimed to assess the causal effects of different gut microbes on TMAO using Mendelian randomization (MR).

Methods

Gut microbiome and TMAO datasets were acquired from genome-wide association studies and screened for single nucleotide polymorphisms according to the basic assumptions of MR. Inverse variance weighted was used as the main method in MR analysis to assess the causal relationship between the gut microbiome and TMAO. Finally, the MR-Egger intercept, Cochran's Q test, and leave-one-out sensitivity analysis were used to assess the horizontal pleiotropy, heterogeneity, and robustness of the results, respectively.

Results

MR analysis revealed that the species Bacteroides finegoldii (odds ratio [OR] 1.064, 95% confidence interval [CI] 1.003 to 1.128, p = 0.039), family Sutterellaceae (OR 1.188, 95% CI 1.003 to 1.407, p = 0.047), and phylum Pseudomonadota (OR 1.205, 95% CI 1.036 to 1.401, p = 0.016), as well as the species Bacteroides uniformis (OR 1.263, 95% CI 1.039 to 1.535, p = 0.019), were positively associated with increased genetic susceptibility to TMAO. In contrast, the species Bacteroides thetaiotaomicron (OR 0.813, 95% CI 0.696 to 0.950, p = 0.009) and Bilophila wadsworthia (OR 0.828, 95% CI 0.690 to 0.995, p = 0.044) were associated with reduced genetic susceptibility to TMAO. Additionally, the MR-Egger intercept indicated no horizontal pleiotropy (p ≥ 0.05), and Cochran's Q test and sensitivity analysis demonstrated that the results were not heterogeneous (p ≥ 0.05) and were robust.

Conclusion

Our findings revealed the role of the phylum Pseudomonadota, family Sutterellaceae, species Bacteroides finegoldii, and Bacteroides uniformis in increasing TMAO, as well as the species Bacteroides thetaiotaomicron and Bilophila wadsworthia in decreasing TMAO. This study provides new insights into the relationship between the gut microbiome and TMAO levels.

Role of inflammatory cytokines and the gut microbiome in vascular dementia: insights from Mendelian randomization analysis

Background

Both inflammatory cytokines and the gut microbiome are susceptibility factors for vascular dementia (VaD). The trends in the overall changes in the dynamics of inflammatory cytokines and in the composition of the gut microbiome are influenced by a variety of factors, making it difficult to fully explain the different effects of both on the different subtypes of VaD. Therefore, this Mendelian randomization (MR) study identified the inflammatory cytokines and gut microbiome members that influence the risk of developing VaD and their causal effects, and investigated whether inflammatory cytokines are gut microbiome mediators affecting VaD.

Methods

We obtained pooled genome-wide association study (GWAS) data for 196 gut microbiota and 41 inflammatory cytokines and used GWAS data for six VaD subtypes, namely, VaD (mixed), VaD (multiple infarctions), VaD (other), VaD (subcortical), VaD (sudden onset), and VaD (undefined). We used the inverse-variance weighted (IVW) method as the primary MR analysis method. We conducted sensitivity analyses and reverse MR analyses to examine reverse causal associations, enhancing the reliability and stability of the conclusions. Finally, we used multivariable MR (MVMR) analysis to assess the direct causal effects of inflammatory cytokines and the gut microbiome on the risk of VaD, and performed mediation MR analysis to explore whether inflammatory factors were potential mediators.

Results

Our two-sample MR study revealed relationships between the risk of six VaD subtypes and inflammatory cytokines and the gut microbiota: 7 inflammatory cytokines and 14 gut microbiota constituents were positively correlated with increased VaD subtype risk, while 2 inflammatory cytokines and 11 gut microbiota constituents were negatively correlated with decreased VaD subtype risk. After Bonferroni correction, interleukin-18 was correlated with an increased risk of VaD (multiple infarctions); macrophage migration inhibitory factor was correlated with an increased risk of VaD (sudden onset); interleukin-4 was correlated with a decreased risk of VaD (other); Ruminiclostridium 6 and Bacillales were positively and negatively correlated with the risk of VaD (undefined), respectively; Negativicutes and Selenomonadales were correlated with a decreased risk of VaD (mixed); and Melainabacteria was correlated with an increased risk of VaD (multiple infarctions). Sensitivity analyses revealed no multilevel effects or heterogeneity and no inverse causality between VaD and inflammatory cytokines or the gut microbiota. The MVMR results further confirmed that the causal effects of Negativicutes, Selenomonadales, and Melainabacteria on VaD remain significant. Mediation MR analysis showed that inflammatory cytokines were not potential mediators.

Conclusion

This study helps us to better understand the pathological mechanisms of VaD and suggests the potential value of targeting increases or decreases in inflammatory cytokines and gut microbiome members for VaD prevention and intervention.

Gut microbiome and metabolome alterations in traditional Chinese medicine damp-heat constitution following treatment with a Chinese patent medicine and lifestyle intervention

BACKGROUND

The gut microbiota is crucial in human health and diseases. Traditional Chinese Medicine Constitution (TCMC) divides people into those with a balanced constitution (Ping-he [PH]) and those with an unbalanced constitution. Dampness-heat constitution (Shi-re [SR]) is a common unbalanced constitution in the Chinese population and is susceptible to diseases. However, unbalanced constitutions can be regulated by Chinese medicine and lifestyle interventions in clinical practice. Ermiao Pill (EMP) is a Chinese medicine known for clearing heat and draining dampness and improving SR. However, the efficacy and mechanism of EMP are unclear.

HYPOTHESIS/PURPOSE

To determine alterations in the gut microbiota and metabolome in SR and any changes after EMP treatment combined with lifestyle intervention.

STUDY DESIGN

Randomized clinical trial.

METHODS

We enrolled 112 healthy SR individuals and evaluated the efficacy of EMP along with lifestyle interventions. We further assessed serum cytokine levels, serum and urinary metabolomes, and the gut microbiota by 16S rRNA gene sequencing analysis before and after the EMP and lifestyle interventions.

RESULTS

107 SR individuals (55 in the intervention group and 52 in the control group) completed the 1-month-intervention and 1-year-follow-up. The intervention group significantly improved their health status within 1 month, with a reduced SR symptom score, and the efficacy lasted to the 1-year follow-up. The control group needed a further 6 months to reduce the SR symptom score. The gut microbiota of PH individuals was more diverse and had significantly higher proportions of many bacterial species than the SR. Microbiota co-occurrence network analysis showed that SR enriches metabolites correlating with microbial community structure, consistent with traits of healthy SR-enriched microbiota.

CONCLUSION

EMP combined with lifestyle intervention produced health benefits in SR individuals. Our study indicates a pivotal role of gut microbiota and metabolome alterations in distinguishing between healthy SR and PH. Furthermore, the study reveals structural changes of gut microbiota and metabolites induced by EMP and lifestyle intervention. The treatment enriched the number of beneficial bacteria, such as Akkermansia muciniphila and Lactobacillus in the gut. Our findings provide a strong indication that several metabolite factors are associated with the gut microbiota. Moreover, the gut microbiome and metabolome might be powerful tools for TCMC diagnosis and personalized therapy.

The influence of aging and the microbiome in multiple sclerosis and other neurologic diseases

The human gut microbiome is well-recognized as a key player in maintaining health. However, it is a dynamic entity that changes across the lifespan. How the microbial changes that occur in later decades of life shape host health or impact age-associated inflammatory neurological diseases such as multiple sclerosis (MS) is still unclear. Current understanding of the aging gut microbiome is largely limited to cross-sectional observational studies. Moreover, studies in humans are limited by confounding host-intrinsic and extrinsic factors that are not easily disentangled from aging. This review provides a comprehensive summary of existing literature on the aging gut microbiome and its known relationships with neurological diseases, with a specific focus on MS. We will also discuss preclinical animal models and human studies that shed light on the complex microbiota-host interactions that have the potential to influence disease pathology and progression in aging individuals. Lastly, we propose potential avenues of investigation to deconvolute features of an aging microbiota that contribute to disease, or alternatively promote health in advanced age.

Role of Trimethylamine N-Oxide in Heart Failure

Heart failure (HF) is a clinical syndrome characterizing by typical physical signs and symptomatology resulting from reduced cardiac output and/or intracardiac pressure at rest or under stress due to structural and/or functional abnormalities of the heart. HF is often the final stage of all cardiovascular diseases and a significant risk factor for sudden cardiac arrest, death, and liver or kidney failure. Current pharmacological treatments can only slow the progression and recurrence of HF. With advancing research into the gut microbiome and its metabolites, one such trimethylamine N-oxide (TMAO)-has been implicated in the advancement of HF and is correlated with poor prognosis in patients with HF. However, the precise role of TMAO in HF has not yet been clarified. This review highlights and concludes the available evidence and potential mechanisms associated with HF, with the hope of contributing new insights into the diagnosis and prevention of HF.

Gut microbiota: a potential new regulator of hypertension

Hypertension is a significant risk factor for cardiovascular and cerebrovascular diseases and has become a global public health concern. Although hypertension results from a combination of factors, the specific mechanism is still unclear. However, increasing evidence suggests that gut microbiota is closely associated with the development of hypertension. We provide a summary of the composition and physiological role of gut microbiota. We then delve into the mechanism of gut microbiota and its metabolites involved in the occurrence and development of hypertension. Finally, we review various regimens for better-controlling hypertension from the diet, exercise, drugs, antibiotics, probiotics, and fecal transplantation perspectives.

Vertical Transfer of Maternal Gut Microbes to Offspring of Western Diet-Fed Dams Drives Reduced Levels of Tryptophan Metabolites and Postnatal Innate Immune Response

Maternal obesity and/or Western diet (WD) is associated with an increased risk of metabolic dysfunction-associated steatotic liver disease (MASLD) in offspring, driven, in part, by the dysregulation of the early life microbiome. Here, using a mouse model of WD-induced maternal obesity, we demonstrate that exposure to a disordered microbiome from WD-fed dams suppressed circulating levels of endogenous ligands of the aryl hydrocarbon receptor (AHR; indole, indole-3-acetate) and TMAO (a product of AHR-mediated transcription), as well as hepatic expression of Il10 (an AHR target), in offspring at 3 weeks of age. This signature was recapitulated by fecal microbial transfer from WD-fed pregnant dams to chow-fed germ-free (GF) lactating dams following parturition and was associated with a reduced abundance of Lactobacillus in GF offspring. Further, the expression of Il10 was downregulated in liver myeloid cells and in LPS-stimulated bone marrow-derived macrophages (BMDM) in adult offspring, suggestive of a hypo-responsive, or tolerant, innate immune response. BMDMs from adult mice lacking AHR in macrophages exhibited a similar tolerogenic response, including diminished expression of Il10. Overall, our study shows that exposure to maternal WD alters microbial metabolites in the offspring that affect AHR signaling, potentially contributing to innate immune hypo-responsiveness and progression of MASLD, highlighting the impact of early life gut dysbiosis on offspring metabolism. Further investigations are warranted to elucidate the complex interplay between maternal diet, gut microbial function, and the development of neonatal innate immune tolerance and potential therapeutic interventions targeting these pathways.

Trimethylamine N-oxide ameliorates hepatic damage including reduction of hepatic bile acids and cholesterol in Fxr-null mice

There are conflicting animal experiments on the effect of trimethylamine N-oxide (TMAO), the dietary metabolite, on non-alcoholic fatty liver disease (NAFLD). This study aims to determine the effect of TMAO on NAFLD. A diet containing 0.3% TMAO was fed to farnesoid X receptor (Fxr)-null mice, a model of NAFLD, for 13 weeks. Fxr-null mice fed TMAO showed significant reductions in liver damage markers but not wild-type mice. Hepatic bile acid and cholesterol levels were significantly decreased, and triacylglycerol levels tended to decrease in TMAO-fed Fxr-null mice. Changes in mRNA levels of hepatic bile acid and cholesterol transporters and synthetic enzymes were observed, which could explain the decreased hepatic bile acid and cholesterol levels in Fxr-null mice given the TMAO diet but not in the wild-type mice. These results suggest that TMAO intake ameliorates liver damage in Fxr-null mice, further altering bile acid/cholesterol metabolism in an FXR-independent manner.

Deciphering the causal relationship between plasma and cerebrospinal fluid metabolites and glioblastoma multiforme: a Mendelian Randomization study

BACKGROUND

Glioblastoma Multiforme (GBM) is one of the most aggressive and fatal brain cancers. The study of metabolites could be crucial for understanding GBM's biology and reveal new treatment strategies.

METHODS

The GWAS data for GBM were sourced from the FinnGen database. A total of 1400 plasma metabolites were collected from the GWAS Catalog dataset. The cerebrospinal fluid (CSF) metabolites data were collected from subsets of participants in the WADRC and WRAP studies. We utilized the inverse variance weighting (IVW) method as the primary tool to explore the causal relationship between metabolites in plasma and CSF and glioblastoma, ensuring the exclusion of instances with horizontal pleiotropy. Additionally, four supplementary analytical methods were applied to reinforce our findings. Aberrant results were identified and omitted based on the outcomes of the leave-one-out sensitivity analysis. Conclusively, a reverse Mendelian Randomization analysis was also conducted to further substantiate our results.

RESULTS

The study identified 69 plasma metabolites associated with GBM. Of these, 40 metabolites demonstrated a significant positive causal relationship with GBM, while 29 exhibited a significant negative causal association. Notably, Trimethylamine N-oxide (TMAO) levels in plasma, not CSF, were found to be a significant exposure factor for GBM (OR = 3.1627, 95% CI = (1.6347, 6.1189), P = 0.0006). The study did not find a reverse causal relationship between GBM and plasma TMAO levels.

CONCLUSIONS

This research has identified 69 plasma metabolites potentially associated with the incidence of GBM, among which TMAO stands out as a promising candidate for an early detectable biomarker for GBM.

Gut microbiota-generated metabolites: missing puzzles to hosts' health, diseases, and aging

The gut microbiota, an intricate community of bacteria residing in the gastrointestinal system, assumes a pivotal role in various physiological processes. Beyond its function in food breakdown and nutrient absorption, gut microbiota exerts a profound influence on immune and metabolic modulation by producing diverse gut microbiota-generated metabolites (GMGMs). These small molecules hold potential to impact host health via multiple pathways, which exhibit remarkable diversity, and have gained increasing attention in recent studies. Here, we elucidate the intricate implications and significant impacts of four specific metabolites, Urolithin A (UA), equol, Trimethylamine N-oxide (TMAO), and imidazole propionate, in shaping human health. Meanwhile, we also look into the advanced research on GMGMs, which demonstrate promising curative effects and hold great potential for further clinical therapies. Notably, the emergence of positive outcomes from clinical trials involving GMGMs, typified by UA, emphasizes their promising prospects in the pursuit of improved health and longevity. Collectively, the multifaceted impacts of GMGMs present intriguing avenues for future research and therapeutic interventions. [BMB Reports 2024; 57(5): 207-215].

TMAO enhances TNF-α mediated fibrosis and release of inflammatory mediators from renal fibroblasts

Trimethylamine-N-oxide (TMAO) is a gut microbiota-derived metabolite and TNF-α is proinflammatory cytokine, both known to be associated with renal inflammation, fibrosis and chronic kidney disease. However, today there are no data showing the combined effect of TMAO and TNF-α on renal fibrosis-and inflammation. The aim of this study was to investigate whether TMAO can enhance the inflammatory and fibrotic effects of TNF-α on renal fibroblasts. We found that the combination of TNF-α and TMAO synergistically increased fibronectin release and total collagen production from renal fibroblasts. The combination of TMAO and TNF-α also promoted increased cell proliferation. Both renal proliferation and collagen production were mediated through Akt/mTOR/ERK signaling. We also found that TMAO enhanced TNF-α mediated renal inflammation by inducing the release of several cytokines (IL-6, LAP TGF-beta-1), chemokines (CXCL-6, MCP-3), inflammatory-and growth mediators (VEGFA, CD40, HGF) from renal fibroblasts. In conclusion, we showed that TMAO can enhance TNF-α mediated renal fibrosis and release of inflammatory mediators from renal fibroblasts in vitro. Our results can promote further research evaluating the combined effect of TMAO and inflammatory mediators on the development of kidney disease.

Microbial Metabolite Trimethylamine N-Oxide Promotes Campylobacter jejuni Infection by Escalating Intestinal Inflammation, Epithelial Damage, and Barrier Disruption

The interactions between Campylobacter jejuni , a critical foodborne cause of gastroenteritis, and the intestinal microbiota during infection are not completely understood. The crosstalk between C. jejuni and its host is impacted by the gut microbiota through mechanisms of competitive exclusion, microbial metabolites, or immune response. To investigate the role of gut microbiota on C. jejuni pathogenesis, we examined campylobacteriosis in the IL10KO mouse model, which was characterized by an increase in the relative abundance of intestinal proteobacteria, E. coli , and inflammatory cytokines during C. jejuni infection. We also found a significantly increased abundance of microbial metabolite Trimethylamine N-Oxide (TMAO) in the colonic lumens of IL10KO mice. We further investigated the effects of TMAO on C. jejuni pathogenesis. We determined that C. jejuni senses TMAO as a chemoattractant and the administration of TMAO promotes C. jejuni invasion into Caco-2 monolayers. TMAO also increased the transmigration of C. jejuni across polarized monolayers of Caco-2 cells, decreased TEER, and increased C. jejuni -mediated intestinal barrier damage. Interestingly, TMAO treatment and presence during C. jejuni infection of Caco-2 cells synergistically caused an increased inflammatory cytokine expression, specifically IL-1β and IL-8. These results establish that C. jejuni utilizes microbial metabolite TMAO for increased virulence during infection.

Blood-Based Multiomics-Guided Detection of a Precancerous Pancreatic Tumor

Over a decade ago, longitudinal multiomics analysis was pioneered for early disease detection and individually tailored precision health interventions. However, high sample processing costs, expansive multiomics measurements along with complex data analysis have made this approach to precision/personalized medicine impractical. Here we describe in a case report, a more practical approach that uses fewer measurements, annual sampling, and faster decision making. We also show how this approach offers promise to detect an exceedingly rare and potentially fatal condition before it fully manifests. Specifically, we describe in the present case report how longitudinal multiomics monitoring (LMOM) helped detect a precancerous pancreatic tumor and led to a successful surgical intervention. The patient, enrolled in an annual blood-based LMOM since 2018, had dramatic changes in the June 2021 and 2022 annual metabolomics and proteomics results that prompted further clinical diagnostic testing for pancreatic cancer. Using abdominal magnetic resonance imaging, a 2.6 cm lesion in the tail of the patient's pancreas was detected. The tumor fluid from an aspiration biopsy had 10,000 times that of normal carcinoembryonic antigen levels. After the tumor was surgically resected, histopathological findings confirmed it was a precancerous pancreatic tumor. Postoperative omics testing indicated that most metabolite and protein levels returned to patient's 2018 levels. This case report illustrates the potentials of blood LMOM for precision/personalized medicine, and new ways of thinking medical innovation for a potentially life-saving early diagnosis of pancreatic cancer. Blood LMOM warrants future programmatic translational research with the goals of precision medicine, and individually tailored cancer diagnoses and treatments.

Gut microbiota in relationship to diabetes mellitus and its late complications with a focus on diabetic foot syndrome: A review

Diabetes mellitus is a chronic disease affecting glucose metabolism. The pathophysiological reactions underpinning the disease can lead to the development of late diabetes complications. The gut microbiota plays important roles in weight regulation and the maintenance of a healthy digestive system. Obesity, diabetes mellitus, diabetic retinopathy, diabetic nephropathy and diabetic neuropathy are all associated with a microbial imbalance in the gut. Modern technical equipment and advanced diagnostic procedures, including xmolecular methods, are commonly used to detect both quantitative and qualitative changes in the gut microbiota. This review summarises collective knowledge on the role of the gut microbiota in both types of diabetes mellitus and their late complications, with a particular focus on diabetic foot syndrome.

Inflammation and Organic Cation Transporters Novel (OCTNs)

Inflammation is a physiological condition characterized by a complex interplay between different cells handled by metabolites and specific inflammatory-related molecules. In some pathological situations, inflammation persists underlying and worsening the pathological state. Over the years, two membrane transporters namely OCTN1 (SLC22A4) and OCTN2 (SLC22A5) have been shown to play specific roles in inflammation. These transporters form the OCTN subfamily within the larger SLC22 family. The link between these proteins and inflammation has been proposed based on their link to some chronic inflammatory diseases such as asthma, Crohn's disease (CD), and rheumatoid arthritis (RA). Moreover, the two transporters show the ability to mediate the transport of several compounds including carnitine, carnitine derivatives, acetylcholine, ergothioneine, and gut microbiota by-products, which have been specifically associated with inflammation for their anti- or proinflammatory action. Therefore, the absorption and distribution of these molecules rely on the presence of OCTN1 and OCTN2, whose expression is modulated by inflammatory cytokines and transcription factors typically activated by inflammation. In the present review, we wish to provide a state of the art on OCTN1 and OCTN2 transport function and regulation in relationships with inflammation and inflammatory diseases focusing on the metabolic signature collected in different body districts and gene polymorphisms related to inflammatory diseases.

Trimethylamine-N-oxide and cerebral stroke risk: A review

Trimethylamine-N-oxide (TMAO) is a gut microbiota-derived metabolite produced by the action of gut microbiota and the hepatic enzyme Flavin Mono‑oxygenase 3 (FMO3). TMAO level has a positive correlation with the risk of cardiovascular events, including stroke, and their level is influenced mainly by dietary choice and the action of liver enzyme FMO3. TMAO plays a role in the development of atherosclerosis plaque, which is one of the causative factors of the stroke event. Preclinical and clinical investigations on the TMAO and associated stroke risk, severity, and outcomes are summarised in this review. In addition, mechanisms of TMAO-driven vascular dysfunction are also discussed, such as inflammation, oxidative stress, thrombus and foam cell formation, altered cholesterol and bile acid metabolism, etc. Post-stroke inflammatory cascades involving activation of immune cells, i.e., microglia and astrocytes, result in Blood-brain-barrier (BBB) disruption, allowing TMAO to infiltrate the brain and further aggravate inflammation. This event occurs as a result of the activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway through the release of inflammatory cytokines and chemokines that further aggravate the BBB and initiate further recruitment of immune cells in the brain. Thus, it's likely that maintaining TMAO levels and associated gut microbiota could be a promising approach for treating and improving stroke complications.

Cardioprotective Role of Tinospora cordifolia against Trimethylamine-N-Oxide and Glucose Induced Stress in Rat Cardiomyocytes

BACKGROUND

Type 2 diabetes has become a concern issue that affects the quality of life and can increase the risk of cardiac insufficiency elevating the threat to the life safety of patients. A recognized cause of cardiac insufficiency is diabetic cardiomyopathy, chronic hyperglycemia, and myocardial lipotoxicity which can reduce the myocardial contractile performance, and enhance the cardiomyocyte hypertrophy and interstitial fibrosis. The cause of diabetic cardiomyopathy is multi-factorial which includes oxidative stress, insulin resistance, inflammation, apoptosis, and autophagy. Recent clinical studies have suggested the dysbiosis of gut microbiota, secretion of metabolites, and their diffusion in to the host as to have direct detrimental effects on the cardiac contractility.

MATERIALS AND METHODS

In the present paper, we have done in silico studies including molecular interaction of phytoconstituents of Tinospora cordifolia against reactive oxygen species producing proteins. Whereas, in vitro studies were conducted on H9C2 cardiac cells including cell morphological examination, level of reactive oxygen species, cell count-viability, apoptotic status, in the presence of high glucose, trimethylamine-n-oxide, and plant extracts which were determined through cell analyzer and microscopic assays.

RESULTS

The treatment of high glucose and trimethylamine-n-oxide was found to be increase the cardiac stress approximately two fold by attenuating hypertrophic conditions, oxidative stress, and apoptosis in rat cardiomyocytes, and Tinospora cordifolia was found to be a cardioprotective agent.

CONCLUSION

Conclusively, our study has reported that the Indian medicinal plant Tinospora cordifolia has the ability to treat diabetic cardiomyopathy. Our study can open up a new herbal therapeutic strategy against diabetic cardiomyopathy.

Recent progress in metabolomics for analyzing common infertility conditions that affect ovarian function

Background

Numerous efforts have been undertaken to identify biomarkers associated with embryo and oocyte quality to improve the success rate of in vitro fertilization. Metabolomics has gained traction for its ability to detect dynamic biological changes in real time and provide comprehensive metabolite profiles. This review synthesizes the most recent findings on metabolomic analysis of follicular fluid (FF) in clinical conditions leading to infertility, with a focus on the dynamics of energy metabolism and oocyte quality, and discusses future research directions.

Methods

A literature search was conducted without time constraints.

Main findings

The metabolites present in FF originate from five primary pathways: glycolysis, oxidative phosphorylation, lipid metabolism and β-oxidation, nucleic acid synthesis, and ketogenesis. Metabolomic profiling can broadly categorize infertile women into two groups: those with infertility due to aging and endometriosis, and those with infertility associated with polycystic ovarian syndrome and obesity. In the former group, glycolysis and lipid metabolism are upregulated to compensate for mitochondrial dysfunction, whereas the latter group exhibits the opposite trend. Assessing the levels of glucose, pyruvate, lactate, and plasmalogens in FF may be valuable for evaluating oocyte quality.

Conclusion

Metabolomic analysis, particularly focusing on energy metabolism in FF, holds promise for predicting female reproductive outcomes.

Hypercoagulability in Sickle Cell Disease: A Thrombo-Inflammatory Mechanism

Sickle cell disease (SCD) is a group of inherited disorders characterized by the presence of abnormal hemoglobin S. Patients with SCD suffer from frequent episodes of anemia, chronic hemolysis, pain crisis, and vaso-occlusion. Additionally, SCD is associated with diverse and serious clinical complications, including thrombosis, which can lead to organ failure, increased morbidity, and eventually, mortality. SCD is known to be a hypercoagulable condition, and the cause of hypercoagulability is multifactorial, with the molecular basis of hemoglobin S being the main driver. The presence of hemoglobin S induces sickling of the RBCs and their subsequent hemolysis, as well as oxidative stress. Both of these processes can alter the hemostatic system, through the activation of platelets, coagulation system, and fibrinolysis, as well as depletion of coagulation inhibitors. These changes can also induce the formation of microvesicles and expression of tissue factor, leading to activation of WBCs, endothelial cell damage, and inflammatory response. Understanding the various factors that drive hypercoagulability as a thrombo-inflammatory mechanism in SCD can help provide explanations for the pathogenesis and other complications of the disease.

Talk to Me-Interplay between Mitochondria and Microbiota in Aging

The existence of mitochondria in eukaryotic host cells as a remnant of former microbial organisms has been widely accepted, as has their fundamental role in several diseases and physiological aging. In recent years, it has become clear that the health, aging, and life span of multicellular hosts are also highly dependent on the still-residing microbiota, e.g., those within the intestinal system. Due to the common evolutionary origin of mitochondria and these microbial commensals, it is intriguing to investigate if there might be a crosstalk based on preserved common properties. In the light of rising knowledge on the gut-brain axis, such crosstalk might severely affect brain homeostasis in aging, as neuronal tissue has a high energy demand and low tolerance for according functional decline. In this review, we summarize what is known about the impact of both mitochondria and the microbiome on the host's aging process and what is known about the aging of both entities. For a long time, bacteria were assumed to be immortal; however, recent evidence indicates their aging and similar observations have been made for mitochondria. Finally, we present pathways by which mitochondria are affected by microbiota and give information about therapeutic anti-aging approaches that are based on current knowledge.

Periodontal Disease and Other Adverse Health Outcomes Share Risk Factors, including Dietary Factors and Vitamin D Status

For nearly a century, researchers have associated periodontal disease (PD) with risks of other adverse health outcomes such as cardiovascular disease, diabetes mellitus, and respiratory diseases, as well as adverse pregnancy outcomes. Those findings have led to the hypothesis that PD causes those adverse health outcomes either by increasing systemic inflammation or by the action of periodontopathic bacteria. However, experiments largely failed to support that hypothesis. Instead, the association is casual, not causal, and is due to shared underlying modifiable risk factors, including smoking, diet, obesity, low levels of physical activity, and low vitamin D status. Diabetes mellitus is also considered a risk factor for PD, whereas red and processed meat are the most important dietary risk factors for diabetes. Because PD generally develops before other adverse health outcomes, a diagnosis of PD can alert patients that they could reduce the risk of adverse health outcomes with lifestyle changes. In addition, type 2 diabetes mellitus can often be reversed rapidly by adopting an anti-inflammatory, nonhyperinsulinemic diet that emphasizes healthful, whole plant-based foods. This review describes the evidence that proinflammatory and prohyperinsulinemia diets and low vitamin D status are important risk factors for PD and other adverse health outcomes. We also make recommendations regarding dietary patterns, food groups, and serum 25-hydroxyvitamin D concentrations. Oral health professionals should routinely inform patients with PD that they could reduce their risk of severe PD as well as the risks of many other adverse health outcomes by making appropriate lifestyle changes.

Diet's Role in Modifying Risk of Alzheimer's Disease: History and Present Understanding

Diet is an important nonpharmacological risk-modifying factor for Alzheimer's disease (AD). The approaches used here to assess diet's role in the risk of AD include multi-country ecological studies, prospective and cross-sectional observational studies, and laboratory studies. Ecological studies have identified fat, meat, and obesity from high-energy diets as important risk factors for AD and reported that AD rates peak about 15-20 years after national dietary changes. Observational studies have compared the Western dietary pattern with those of the Dietary Approaches to Stop Hypertension (DASH), Mediterranean (MedDi), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diets. Those studies identified AD risk factors including higher consumption of saturated and total fats, meat, and ultraprocessed foods and a lower risk of AD with higher consumption of fruits, legumes, nuts, omega-3 fatty acids, vegetables, and whole grains. Diet-induced factors associated with a significant risk of AD include inflammation, insulin resistance, oxidative stress, elevated homocysteine, dietary advanced glycation end products, and trimethylamine N-oxide. The molecular mechanisms by which dietary bioactive components and specific foods affect risk of AD are discussed. Given most countries' entrenched food supply systems, the upward trends of AD rates would be hard to reverse. However, for people willing and able, a low-animal product diet with plenty of anti-inflammatory, low-glycemic load foods may be helpful.