Metabolomics Signature in Prediabetes and Diabetes: Insights From Tandem Mass Spectrometry Analysis.

OBJECTIVE: This study investigates the metabolic differences between normal, prediabetic and diabetic patients with good and poor glycaemic control (GGC and PGC). DESIGN: In this study, 1102 individuals were included, and 50 metabolites were analysed using tandem mass spectrometry. The diabetes diagnosis and treatment standards of the American Diabetes Association (ADA) were used to classify patients. METHODS: The nearest neighbour method was used to match controls and cases in each group on the basis of age, sex and BMI. Factor analysis was used to reduce the number of variables and find influential underlying factors. Finally, Pearson's correlation coefficient was used to check the correlation between both glucose and HbAc1 as independent factors with binary classes. RESULTS: Amino acids such as glycine, serine and proline, and acylcarnitines (AcylCs) such as C16 and C18 showed significant differences between the prediabetes and normal groups. Additionally, several metabolites, including C0, C5, C8 and C16, showed significant differences between the diabetes and normal groups. Moreover, the study found that several metabolites significantly differed between the GGC and PGC diabetes groups, such as C2, C6, C10, C16 and C18. The correlation analysis revealed that glucose and HbA1c levels significantly correlated with several metabolites, including glycine, serine and C16, in both the prediabetes and diabetes groups. Additionally, the correlation analysis showed that HbA1c significantly correlated with several metabolites, such as C2, C5 and C18, in the controlled and uncontrolled diabetes groups. CONCLUSIONS: These findings could help identify new biomarkers or underlying markers for the early detection and management of diabetes.

Influence of Dietary Polyunsaturated Fatty Acid Intake on Potential Lipid Metabolite Diagnostic Markers in Renal Cell Carcinoma: A Case-Control Study.

Non-invasive diagnostics are crucial for the timely detection of renal cell carcinoma (RCC), significantly improving survival rates. Despite advancements, specific lipid markers for RCC remain unidentified. We aimed to discover and validate potent plasma markers and their association with dietary fats. Using lipid metabolite quantification, machine-learning algorithms, and marker validation, we identified RCC diagnostic markers in studies involving 60 RCC and 167 healthy controls (HC), as well as 27 RCC and 74 HC, by analyzing their correlation with dietary fats. RCC was associated with altered metabolism in amino acids, glycerophospholipids, and glutathione. We validated seven markers (l-tryptophan, various lysophosphatidylcholines [LysoPCs], decanoylcarnitine, and l-glutamic acid), achieving a 96.9% AUC, effectively distinguishing RCC from HC. Decreased decanoylcarnitine, due to reduced carnitine palmitoyltransferase 1 (CPT1) activity, was identified as affecting RCC risk. High intake of polyunsaturated fatty acids (PUFAs) was negatively correlated with LysoPC (18:1) and LysoPC (18:2), influencing RCC risk. We validated seven potential markers for RCC diagnosis, highlighting the influence of high PUFA intake on LysoPC levels and its impact on RCC occurrence via CPT1 downregulation. These insights support the efficient and accurate diagnosis of RCC, thereby facilitating risk mitigation and improving patient outcomes.

Liver sinusoidal endothelial cells rely on oxidative phosphorylation but avoid processing long-chain fatty acids in their mitochondria.

BACKGROUND: It is generally accepted that endothelial cells (ECs), primarily rely on glycolysis for ATP production, despite having functional mitochondria. However, it is also known that ECs are heterogeneous, and their phenotypic features depend on the vascular bed. Emerging evidence suggests that liver sinusoidal ECs (LSECs), located in the metabolically rich environment of the liver, show high metabolic plasticity. However, the substrate preference for energy metabolism in LSECs remains unclear. METHODS: Investigations were conducted in primary murine LSECs in vitro using the Seahorse XF technique for functional bioenergetic assays, untargeted mass spectrometry-based proteomics to analyse the LSEC proteome involved in energy metabolism pathways, liquid chromatography-tandem mass spectrometry-based analysis of acyl-carnitine species and Raman spectroscopy imaging to track intracellular palmitic acid. RESULTS: This study comprehensively characterized the energy metabolism of LSECs, which were found to depend on oxidative phosphorylation, efficiently fuelled by glucose-derived pyruvate, short- and medium-chain fatty acids and glutamine. Furthermore, despite its high availability, palmitic acid was not directly oxidized in LSEC mitochondria, as evidenced by the acylcarnitine profile and etomoxir's lack of effect on oxygen consumption. However, together with L-carnitine, palmitic acid supported mitochondrial respiration, which is compatible with the chain-shortening role of peroxisomal ß-oxidation of long-chain fatty acids before further degradation and energy generation in mitochondria. CONCLUSIONS: LSECs show a unique bioenergetic profile of highly metabolically plastic ECs adapted to the liver environment. The functional reliance of LSECs on oxidative phosphorylation, which is not a typical feature of ECs, remains to be determined.

Biocompatible Tough Ionogels with Reversible Supramolecular Adhesion.

Cohesive and interfacial adhesion energies are difficult to balance to obtain reversible adhesives with both high mechanical strength and high adhesion strength, although various methods have been extensively investigated. Here, a biocompatible citric acid/L-(-)-carnitine (CAC)-based ionic liquid was developed as a solvent to prepare tough and high adhesion strength ionogels for reversible engineered and biological adhesives. The prepared ionogels exhibited good mechanical properties, including tensile strength (14.4 MPa), Young's modulus (48.1 MPa), toughness (115.2 MJ m-3), and high adhesion strength on the glass substrate (24.4 MPa). Furthermore, the ionogels can form mechanically matched tough adhesion at the interface of wet biological tissues (interfacial toughness about 191 J m-2) and can be detached by saline solution on demand, thus extending potential applications in various clinical scenarios such as wound adhesion and nondestructive transfer of organs.

Evaluation of the first 5 years of a glutaric aciduria type I neonatal screening programme in Asturias.

INTRODUCTION: . Neonatal screening of glutaric aciduria type 1 (GA-1) has brought radical changes in the course and outcomes of this disease. This study analyses the outcomes of the first 5 years (2015-2019) of the AGA1 neonatal screening programme in our autonomous community. MATERIAL: . We conducted an observational, descriptive and retrospective study. All neonates born between January 1, 2015 and December 31, 2019 that participated in the neonatal screening programme were included in the study. The glutarylcarnitine (C5DC) concentration in dry blood spot samples was measured by means of tandem mass spectrometry applying a cut-off point of 0.25 µmol/L. RESULTS: . A total of 30 120 newborns underwent screening. We found differences in the C5DC concentration based on gestational age, type of feeding and hours of life at sample collection. These differences were not relevant for screening purposes. There were no differences between neonates with weights smaller and greater than 1500 g. Screening identified 2 affected patients and there were 3 false positives. There were no false negatives. The diagnosis was confirmed by genetic testing. Patients have been in treatment since diagnosis and have not developed encephalopathic crises in the first 4 years of life. CONCLUSIONS: . Screening allowed early diagnosis of two cases of GA-1 in the first 5 years since its introduction in our autonomous community. Although there were differences in C5DC levels based on gestational age, type of feeding and hours of life at blood extraction, they were not relevant for screening.

Analysis of the intestinal microbiota and profiles of blood amino acids and acylcarnitines in neonates with hyperbilirubinemia.

OBJECTIVE: This study aimed to discuss the distinctive features of the intestinal microbiota in neonates with hyperbilirubinemia and to comprehensively analyse the composition of the intestinal microbiota as well as the levels of free amino acids and acylcarnitines in the peripheral blood of neonates experiencing hyperbilirubinemia. RESULTS: At the phylum level, Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Chloroflexi were the five predominant microbial groups identified in both the hyperbilirubinemia and control groups. Alpha diversity analysis, encompassing seven indices, showed no statistically significant differences between the two groups. However, Beta diversity analysis revealed a significant difference in intestinal microbiota structure between the groups. Linear discriminant analysis effect size (LEfSe) indicated a significant reduction in the abundance of Gammaproteobacteria and Enterobacteriaceae within the hyperbilirubinemia group compared to that in the control group. The heatmap revealed that the control group exhibited increased abundances of Escherichia and Bifidobacterium, while the hyperbilirubinemia group exhibited increased levels of Enterococcus and Streptococcus. Regarding blood amino acids and acylcarnitines, there were greater concentrations of citrulline (Cit), arginine (Arg), ornithine (Orn), and valine (Val) in the hyperbilirubinemia group than in the control group. The hyperbilirubinemia group also exhibited significant increases in medium-chain fatty acids (C6, C8), long-chain fatty acids (C18), and free carnitine (C0). CONCLUSION: By comparing neonates with hyperbilirubinemia to those without, a significant disparity in the community structure of the intestinal microbiota was observed. The intestinal microbiota plays a crucial role in the bilirubin metabolism process. The intestinal microbiota of neonates with hyperbilirubinemia exhibited a certain degree of dysbiosis. The abundances of Bacteroides and Bifidobacterium were negatively correlated with the bilirubin concentration. Therefore, the fact that neonates with hyperbilirubinemia exhibit some variations in blood amino acid and acylcarnitine levels may provide, to a certain degree, a theoretical basis for clinical treatment and diagnosis.

An untargeted analytical workflow based on Kendrick mass defect filtering reveals dysregulations in acylcarnitines in prostate cancer tissue.

BACKGROUND: Metabolomics is nowadays considered one the most powerful analytical for the discovery of metabolic dysregulations associated with the insurgence of cancer, given the reprogramming of the cell metabolism to meet the bioenergetic and biosynthetic demands of the malignant cell. Notwithstanding, several challenges still exist regarding quality control, method standardization, data processing, and compound identification. Therefore, there is a need for effective and straightforward approaches for the untargeted analysis of structurally related classes of compounds, such as acylcarnitines, that have been widely investigated in prostate cancer research for their role in energy metabolism and transport and ß-oxidation of fatty acids. RESULTS: In the present study, an innovative analytical platform was developed for the straightforward albeit comprehensive characterization of acylcarnitines based on high-resolution mass spectrometry, Kendrick mass defect filtering, and confirmation by prediction of their retention time in reversed-phase chromatography. In particular, a customized data processing workflow was set up on Compound Discoverer software to enable the Kendrick mass defect filtering, which allowed filtering out more than 90 % of the initial features resulting from the processing of 25 tumoral and adjacent non-malignant prostate tissues collected from patients undergoing radical prostatectomy. Later, a partial least square-discriminant analysis model validated by repeated double cross-validation was built on the dataset of 74 annotated acylcarnitines, with classification rates higher than 93 % for both groups, and univariate statistical analysis helped elucidate the individual role of the annotated metabolites. SIGNIFICANCE: Hydroxylation of short- and medium-chain minor acylcarnitines appeared to be a significant variable in describing tissue differences, suggesting the hypothesis that the neoplastic growth is linked to oxidation phenomena on selected metabolites and reinforcing the need for effective methods for the annotation of minor metabolites.

Assessment of the potential effects of l-carnitine and cinnamon supplementation on weight loss and body composition.

OBJECTIVE: Aim: To assess efficacy of L-carnitine and cinnamon alone and in combination on body composition parameters in addition to compare between them. PATIENTS AND METHODS: Materials and Methods: Sample of 28 obese and overweight adults in Babylon city, sample collection includes patients in places, or by internet, where interview take place according to specialize questionnaire height, weight, and body mass index were measured. RESULTS: Results: A significant differences P<0.05 among gender distribution between male and female. A significant difference between (150-160 cm, 160-170 cm) as compared with (170-180 cm, 180-190 cm). A significant difference between 170-180 cm as compared with 180-190 cm but non-significant differences between 150-160 cm as compared with 160-170 cm. A significant difference between 26-35 as compared with 36-45, 46-55, but non-significant differences between 36-45 as compared with 46-55. A significant difference between body weight, body fat, water content, skeletal muscle, and body mass index after treatment, but non-significant differences between protein, and inorganic salt after treatment and at baseline. A significant difference between body weight, water content, skeletal muscle, and body mass index in group treated with cinnamon as compared with negative control group, but non-significant differences between body fat, protein, and inorganic salt as compared with negative control group. CONCLUSION: Conclusions: The prevalence of overweight and obesity within accepted range of that reported in Iraq, important relationship was reported between several life style risk factor, as soon as diagnose increase in weight and education health program for behavior of life style were high recommended.

L-carnitine and Ginkgo biloba Supplementation In Vivo Ameliorates HCD-Induced Steatohepatitis and Dyslipidemia by Regulating Hepatic Metabolism.

Treatment strategies for steatohepatitis are of special interest given the high prevalence of obesity and fatty liver disease worldwide. This study aimed to investigate the potential therapeutic mechanism of L-carnitine (LC) and Ginkgo biloba leaf extract (GB) supplementation in ameliorating the adverse effects of hyperlipidemia and hepatosteatosis induced by a high-cholesterol diet (HCD) in an animal model. The study involved 50 rats divided into five groups, including a control group, a group receiving only an HCD, and three groups receiving an HCD along with either LC (300 mg LC/kg bw), GB (100 mg GB/kg bw), or both. After eight weeks, various parameters related to lipid and glucose metabolism, antioxidant capacity, histopathology, immune reactivity, and liver ultrastructure were measured. LC + GB supplementation reduced serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, glucose, insulin, HOMA-IR, alanine transaminase, and aspartate transaminase levels and increased high-density lipoprotein cholesterol levels compared with those in the HCD group. Additionally, treatment with both supplements improved antioxidant ability and reduced lipid peroxidation. The histological examination confirmed that the combination therapy reduced liver steatosis and fibrosis while also improving the appearance of cell organelles in the ultrastructural hepatocytes. Finally, the immunohistochemical analysis indicated that cotreatment with LC + GB upregulated the immune expression of GLP-1 and ß-Cat in liver sections that were similar to those of the control animals. Mono-treatment with LC or GB alone substantially but not completely protected the liver tissue, while the combined use of LC and GB may be more effective in treating liver damage caused by high cholesterol than either supplement alone by regulating hepatic oxidative stress and the protein expression of GLP-1 and ß-Cat.

Potential utility of l-carnitine for preventing liver tumors derived from metabolic dysfunction-associated steatohepatitis.

BACKGROUND: Recent reports have unveiled the potential utility of l-carnitine to alleviate metabolic dysfunction-associated steatohepatitis (MASH) by enhancing mitochondrial metabolic function. However, its efficacy at preventing the development of HCC has not been assessed fully. METHODS: l-carnitine (2 g/d) was administered to 11 patients with MASH for 10 weeks, and blood liver function tests were performed. Five patients received a serial liver biopsy, and liver histology and hepatic gene expression were evaluated using this tissue. An atherogenic plus high-fat diet MASH mouse model received long-term l-carnitine administration, and liver histology and liver tumor development were evaluated. RESULTS: Ten-week l-carnitine administration significantly improved serum alanine transaminase and aspartate transaminase levels along with a histological improvement in the NAFLD activity score, while steatosis and fibrosis were not improved. Gene expression profiling revealed a significant improvement in the inflammation and profibrotic gene signature as well as the recovery of lipid metabolism. Long-term l-carnitine administration to atherogenic plus high-fat diet MASH mice substantially improved liver histology (inflammation, steatosis, and fibrosis) and significantly reduced the incidence of liver tumors. l-carnitine directly reduced the expression of the MASH-associated and stress-induced transcriptional factor early growth response 1. Early growth response 1 activated the promoter activity of neural precursor cell expressed, developmentally downregulated protein 9 (NEDD9), an oncogenic protein. Thus, l-carnitine reduced the activation of the NEDD9, focal adhesion kinase 1, and AKT oncogenic signaling pathway. CONCLUSIONS: Short-term l-carnitine administration ameliorated MASH through its anti-inflammatory effects. Long-term l-carnitine administration potentially improved the steatosis and fibrosis of MASH and may eventually reduce the risk of HCC.

Anti-Melanoma Effects of Miconazole: Investigating the Mitochondria Involvement.

Miconazole is an antimycotic drug showing anti-cancer effects in several cancers. However, little is known on its effects in melanoma. A375 and SK-MEL-28 human melanoma cell lines were exposed to miconazole and clotrimazole (up to 100 mM). Proliferation, viability with MTT assay and vascular mimicry were assayed at 24 h treatment. Molecular effects were measured at 6 h, namely, ATP-, ROS-release and mitochondria-related cytofluorescence. A metabolomic profile was also investigated at 6 h treatment. Carnitine was one of the most affected metabolites; therefore, the expression of 29 genes involved in carnitine metabolism was investigated in the public platform GEPIA2 on 461 melanoma patients and 558 controls. After 24 h treatments, miconazole and clotrimazole strongly and significantly inhibited proliferation in the presence of 10% serum on either melanoma cell lines; they also strongly reduced viability and vascular mimicry. After 6 h treatment, ATP reduction and ROS increase were observed, as well as a significant reduction in mitochondria-related fluorescence. Further, in A375, miconazole strongly and significantly altered expression of several metabolites including carnitines, phosphatidyl-cholines, all amino acids and several other small molecules, mostly metabolized in mitochondria. The expression of 12 genes involved in carnitine metabolism was found significantly modified in melanoma patients, 6 showing a significant impact on patients' survival. Finally, miconazole antiproliferation activity on A375 was found completely abrogated in the presence of carnitine, supporting a specific role of carnitine in melanoma protection toward miconazole effect, and was significantly reversed in the presence of caspases inhibitors such as ZVAD-FMK and Ac-DEVD-CHO, and a clear pro-apoptotic effect was observed in miconazole-treated cells, by FACS analysis of Annexin V-FITC stained cells. Miconazole strongly affects proliferation and other biological features in two human melanoma cell lines, as well as mitochondria-related functions such as ATP- and ROS-release, and the expression of several metabolites is largely dependent on mitochondria function. Miconazole, likely acting via carnitine and mitochondria-dependent apoptosis, is therefore suggested as a candidate for further investigations in melanoma treatments.

One substrate many enzymes virtual screening uncovers missing genes of carnitine biosynthesis in human and mouse.

The increasing availability of experimental and computational protein structures entices their use for function prediction. Here we develop an automated procedure to identify enzymes involved in metabolic reactions by assessing substrate conformations docked to a library of protein structures. By screening AlphaFold-modeled vitamin B6-dependent enzymes, we find that a metric based on catalytically favorable conformations at the enzyme active site performs best (AUROC Score=0.84) in identifying genes associated with known reactions. Applying this procedure, we identify the mammalian gene encoding hydroxytrimethyllysine aldolase (HTMLA), the second enzyme of carnitine biosynthesis. Upon experimental validation, we find that the top-ranked candidates, serine hydroxymethyl transferase (SHMT) 1 and 2, catalyze the HTMLA reaction. However, a mouse protein absent in humans (threonine aldolase; Tha1) catalyzes the reaction more efficiently. Tha1 did not rank highest based on the AlphaFold model, but its rank improved to second place using the experimental crystal structure we determined at 2.26 Å resolution. Our findings suggest that humans have lost a gene involved in carnitine biosynthesis, with HTMLA activity of SHMT partially compensating for its function.

Effects of Fat and Carnitine on the Expression of Carnitine Acetyltransferase and Enoyl-CoA Hydratase Short-Chain 1 in the Liver of Juvenile GIFT (Oreochromis niloticus).

Carnitine acetyltransferase (CAT) and Enoyl-CoA hydratase short-chain 1 (ECHS1) are considered key enzymes that regulate the ß-oxidation of fatty acids. However, very few studies have investigated their full length and expression in genetically improved farmed tilapia (GIFT, Oreochromis niloticus), an important aquaculture species in China. Here, we cloned CAT and ECHS1 full-length cDNA via the rapid amplification of cDNA ends, and the expressions of CAT and ECHS1 in the liver of juvenile GIFT were detected in different fat and carnitine diets, as were the changes in the lipometabolic enzymes and serum biochemical indexes of juvenile GIFT in diets with different fat and carnitine levels. CAT cDNA possesses an open reading frame (ORF) of 2167 bp and encodes 461 amino acids, and the ECHS1 cDNA sequence is 1354 bp in full length, the ORF of which encodes a peptide of 391 amino acids. We found that juvenile GIFT had higher lipometabolic enzyme activity and lower blood CHOL, TG, HDL-C, and LDL-C contents when the dietary fat level was 2% or 6% and when the carnitine level was 500 mg/kg. We also found that the expression of ECHS1 and CAT genes in the liver of juvenile GIFT can be promoted by a 500 mg/kg carnitine level and 6% fat level feeding. These results suggested that CAT and ECHS1 may participate in regulating lipid metabolism, and when 2% or 6% fat and 500 mg/kg carnitine are added to the feed, it is the most beneficial to the liver and lipid metabolism of juvenile GIFT. Our results may provide a theoretical basis for GIFT feeding and treating fatty liver disease.

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.

Comparison of metabolic parameters between oral and total parenteral nutrition in children with severe eating disorders.

BACKGROUND: This study investigated changes of lipid parameters in children with severe eating disorders during refeeding in order to explore the optimal timing for lipid preparation administration. METHODS: We prospectively assessed the physical conditions of patients with eating disorders after the start of nutrition therapy. The assessments were performed at admission and at 2 and 4 weeks. Lipid metabolism was assessed based on triglyceride (TG), total cholesterol (TC), and free carnitine (FC) levels, as well as acylcarnitine/free carnitine (AC/FC) ratio. RESULTS: A total of 18 patients were included. Of these, 12 and 6 received an oral diet (OD group) and total parenteral nutrition (TPN group), respectively. The mean body mass indexes at hospital admission were 12.8 kg/m2 in the OD group and 12.7 kg/m2 in the TPN group. At 2 weeks after the start of refeeding, TC, TG, and AC/FC levels were significantly lower in the TPN group than in the OD group. Other blood test results did not show any significant differences between the two groups. CONCLUSIONS: Fat-free glucose-based nutrition promoted lipid metabolism over a 2-week period after the start of refeeding, suggesting that balanced energy and lipid intake are essential, even in TPN.

Plasma Metabolome Predicts Aortic Stiffness and Future Risk of Coronary Artery Disease and Mortality After 23 Years of Follow-Up in the General Population.

BACKGROUND: Increased aortic stiffness (arteriosclerosis) is associated with early vascular aging independent of age and sex. The underlying mechanisms of early vascular aging remain largely unexplored in the general population. We aimed to investigate the plasma metabolomic profile in aortic stiffness (vascular aging) and associated risk of incident cardiovascular disease and mortality. METHODS AND RESULTS: We included 6865 individuals from 2 Swedish population-based cohorts. Untargeted plasma metabolomics was performed by liquid-chromatography mass spectrometry. Aortic stiffness was assessed directly by carotid-femoral pulse wave velocity (PWV) and indirectly by augmentation index (AIx@75). A least absolute shrinkage and selection operator (LASSO) regression model was created on plasma metabolites in order to predict aortic stiffness. Associations between metabolite-predicted aortic stiffness and risk of new-onset cardiovascular disease, cardiovascular mortality, and all-cause mortality were calculated. Metabolite-predicted aortic stiffness (PWV and AIx@75) was positively associated particularly with acylcarnitines, dimethylguanidino valeric acid, glutamate, and cystine. The plasma metabolome predicted aortic stiffness (PWV and AIx@75) with good accuracy (R2=0.27 and R2=0.39, respectively). Metabolite-predicted aortic stiffness (PWV and AIx@75) was significantly correlated with age, sex, systolic blood pressure, body mass index, and low-density lipoprotein. After 23 years of follow-up, metabolite-predicted aortic stiffness (PWV and AIx@75) was significantly associated with increased risk of new-onset coronary artery disease, cardiovascular mortality, and all-cause mortality. CONCLUSIONS: Aortic stiffness is associated particularly with altered metabolism of acylcarnitines, cystine, and dimethylguanidino valeric acid. These metabolic disturbances predict increased risk of new-onset coronary artery disease, cardiovascular mortality, and all-cause mortality after more than 23 years of follow-up in the general population.

Association of Gut Microbiota-Related Metabolites and Type 2 Diabetes in Two Puerto Rican Cohorts.

(1) Aims: Gut microbiota metabolites may play integral roles in human metabolism and disease progression. However, evidence for associations between metabolites and cardiometabolic risk factors is sparse, especially in high-risk Hispanic populations. We aimed to evaluate the cross-sectional and longitudinal relationships between gut microbiota related metabolites and measures of glycemia, dyslipidemia, adiposity, and incident type 2 diabetes in two Hispanic observational cohorts. (2) Methods: We included data from 670 participants of the Boston Puerto Rican Health Study (BPRHS) and 999 participants of the San Juan Overweight Adult Longitudinal Study (SOALS). Questionnaires and clinical examinations were conducted over 3 years of follow-up for SOALS and 6 years of follow-up for BPRHS. Plasma metabolites, including L-carnitine, betaine, choline, and trimethylamine N-oxide (TMAO), were measured at baseline in both studies. We used multivariable linear models to evaluate the associations between metabolites and cardiometabolic risk factors and multivariable logistic and Poisson regressions to assess associations with prevalent and incident type 2 diabetes, adjusted for potential confounding factors. Cohort-specific analyses were combined using a fixed-effects meta-analysis. (3) Results: Higher plasma betaine was prospectively associated with lower fasting glucose [-0.97 mg/dL (95% CI: -1.59, -0.34), p = 0.002], lower HbA1c [-0.02% (95% CI: -0.04, -0.01), p = 0.01], lower HOMA-IR [-0.14 (95% CI: -0.23, -0.05), p = 0.003], and lower fasting insulin [-0.27 mcU/mL (95% CI: -0.51, -0.03), p = 0.02]. Betaine was also associated with a 22% lower incidence of type 2 diabetes (IRR: 0.78, 95% CI: 0.65, 0.95). L-carnitine was associated with lower fasting glucose [-0.68 mg/dL (95% CI: -1.29, -0.07), p = 0.03] and lower HbA1c at follow-up [-0.03% (95% CI: -0.05, -0.01), p < 0.001], while TMAO was associated with higher fasting glucose [0.83 mg/dL (95% CI: 0.22, 1.44), p = 0.01] and higher triglycerides [3.52 mg/dL (95% CI: 1.83, 5.20), p < 0.0001]. Neither choline nor TMAO were associated with incident type 2 diabetes. (4) Conclusions: Higher plasma betaine showed consistent associations with a lower risk of glycemia, insulinemia, and type 2 diabetes. However, TMAO, a metabolite of betaine, was associated with higher glucose and lipid concentrations. These observations demonstrate the importance of gut microbiota metabolites for human cardiometabolic health.

5-Heptadecylresorcinol Improves Aging-Associated Hepatic Fatty Acid Oxidation Dysfunction via Regulating Adipose Sirtuin 3.

Aging-associated hepatic fatty acid (FA) oxidation dysfunction contributes to impaired adaptive thermogenesis. 5-Heptadecylresorcinol (AR-C17) is a prominent functional component of whole wheat and rye, and has been demonstrated to improve the thermogenic capacity of aged mice via the regulation of Sirt3. However, the effect of AR-C17 on aging-associated hepatic FA oxidation dysfunction remains unclear. Here, 18-month-old C57BL/6J mice were orally administered with AR-C17 at a dose of 150 mg/kg/day for 8 weeks. Systemic glucose and lipid metabolism, hepatic FA oxidation, and the lipolysis of white adipose tissues (WAT) were measured. The results showed that AR-C17 improved the hepatic FA oxidation, and especially acylcarnitine metabolism, of aged mice during cold stimulation, with the enhancement of systemic glucose and lipid metabolism. Meanwhile, AR-C17 improved the WAT lipolysis of aged mice, promoting hepatic acylcarnitine production. Furthermore, the adipose-specific Sirt3 knockout mice were used to investigate and verify the regulation mechanism of AR-C17 on aging-associated hepatic FA oxidation dysfunction. The results showed that AR-C17 failed to improve the WAT lipolysis and hepatic FA oxidation of aged mice in the absence of adipose Sirt3, indicating that AR-C17 might indirectly influence hepatic FA oxidation via regulating WAT Sirt3. Our findings suggest that AR-C17 might improve aging-associated hepatic FA oxidation dysfunction via regulating adipose Sirt3.

Causality of genetically determined blood metabolites on irritable bowel syndrome: A Mendelian randomization study.

BACKGROUND: Irritable bowel syndrome (IBS) is one of the most common functional bowel disorders and dysmetabolism plays an important role in the pathogenesis of disease. Nevertheless, there remains a lack of information regarding the causal relationship between circulating metabolites and IBS. A two-sample Mendelian randomization (MR) analysis was conducted in order to evaluate the causal relationship between genetically proxied 486 blood metabolites and IBS. METHODS: A two-sample MR analysis was implemented to assess the causality of blood metabolites on IBS. The study utilized a genome-wide association study (GWAS) to examine 486 metabolites as the exposure variable while employing a GWAS study with 486,601 individuals of European descent as the outcome variable. The inverse-variance weighted (IVW) method was used to estimate the causal relationship of metabolites on IBS, while several methods were performed to eliminate the pleiotropy and heterogeneity. Another GWAS data was used for replication and meta-analysis. In addition, reverse MR and linkage disequilibrium score regression (LDSC) were employed for additional assessment. Multivariable MR analysis was conducted in order to evaluate the direct impact of metabolites on IBS. RESULTS: Three known and two unknown metabolites were identified as being associated with the development of IBS. Higher levels of butyryl carnitine (OR(95%CI):1.10(1.02-1.18),p = 0.009) and tetradecanedioate (OR(95%CI):1.13(1.04-1.23),p = 0.003)increased susceptibility of IBS and higher levels of stearate(18:0)(OR(95%CI):0.72(0.58-0.89),p = 0.003) decreased susceptibility of IBS. CONCLUSION: The metabolites implicated in the pathogenesis of IBS possess potential as biomarkers and hold promise for elucidating the underlying biological mechanisms of this condition.