The regulatory roles of aminoacyl-tRNA synthetase in cardiovascular disease

Preliminary analysis of pathways and their implications during salinity stress in abalone

Transcriptome sequencing has offered immense opportunities to study non-model organisms. Abalone is an important marine mollusk that encounters harsh environmental conditions in its natural habitat and under aquaculture conditions; hence, research that increases molecular information to understand abalone physiology and stress response is noteworthy. Accordingly, the study used transcriptome sequencing of the gill tissues of abalone exposed to low salinity stress. The aim is to explore some enriched pathways during salinity stress and the crosstalk and functions of the genes involved in the candidate biological processes for future further analysis of their expression patterns. The data suggest that abalone genes such as YAP/TAZ, Myc, Nkd, and Axin (involved in the Hippo signaling pathway) and PI3K/Akt, SHC, and RTK (involved in the Ras signaling pathways) might mediate growth and development. Thus, deregulation of the Hippo and Ras pathways by salinity stress could be a possible mechanism by which unfavorable salinities influence growth in abalone. Furthermore, PEPCK, GYS, and PLC genes (mediating the Glucagon signaling pathway) might be necessary for glucose homeostasis, reproduction, and abalone meat sensory qualities; hence, a need to investigate how they might be influenced by environmental stress. Genes such as MYD88, IRAK1/4, JNK, AP-1, and TRAF6 (mediating the MAPK signaling pathway) could be useful in understanding abalone's innate immune response to environmental stresses. Finally, the aminoacyl-tRNA biosynthesis pathway hints at the mechanism by which new raw materials for protein biosynthesis are mobilized for physiological processes and how abalone might respond to this process during salinity stress. Low salinity clearly regulated genes in these pathways in a time-dependent manner, as hinted by the heat maps. In the future, qRT-PCR verification and in-depth study of the various genes and proteins discussed would provide enormous molecular information resources for the abalone biology.

Mitochondrial dysfunction in lipid processing and gastrointestinal disorders

Mitochondrial dysfunctions predominantly cause encephalomyopathies with muscle atrophy and neurodegeneration. However, their impact on other tissues, particularly the gastrointestinal tract, requires further investigation. In a recent report in Nature, Moschandrea et al. used mice deficient in the mitochondrial aminoacyl-tRNA synthetase DARS2 to investigate the role of enterocytic mitochondria in dietary lipid processing and transport. Their work sheds light on the development of gastrointestinal disorders as a result of mitochondrial dysfunction.

Predictive biomarkers for the early detection and management of heart failure

Cardiovascular disease (CVD) is a serious public health concern whose incidence has been on a rise and is projected by the World Health Organization to be the leading global cause of mortality by 2030. Heart failure (HF) is a complicated syndrome resulting from various CVDs of heterogeneous etiologies and exhibits varying pathophysiology, including activation of inflammatory signaling cascade, apoptosis, fibrotic pathway, and neuro-humoral system, thereby leading to compromised cardiac function. During this process, several biomolecules involved in the onset and progression of HF are released into circulation. These circulating biomolecules could serve as unique biomarkers for the detection of subclinical changes and can be utilized for monitoring disease severity. Hence, it is imperative to identify these biomarkers to devise an early predictive strategy to stop the deterioration of cardiac function caused by these complex cellular events. Furthermore, measurement of multiple biomarkers allows clinicians to divide HF patients into sub-groups for treatment and management based on early health outcomes. The present article provides a comprehensive overview of current omics platform available for discovering biomarkers for HF management. Some of the existing and novel biomarkers for the early detection of HF with special reference to endothelial biology are also discussed.

Serine mistranslation induces the integrated stress response without accumulation of uncharged tRNAs

Aminoacyl-tRNA synthetases (aaRSs) are essential enzymes that support robust and accurate protein synthesis. A rapidly expanding number of studies show that mutations in aaRSs lead to multiple human diseases, including neurological disorders and cancer. Much remains unknown about how aaRS mutations impact human health. In particular, how aminoacylation errors affect stress responses and fitness in eukaryotic cells remains poorly understood. The integrated stress response (ISR) is an adaptive mechanism in response to multiple stresses. However, chronic activation of the ISR contributes to the development of multiple diseases (e.g., neuropathies). Here we show that Ser misincorporation into Ala and Thr codons, resulting from aaRS editing defects or mutations in tRNAs, constitutively active the ISR. Such activation does not appear to depend on the accumulation of uncharged tRNAs, implicating that Ser mistranslation may lead to ribosome stalling and collision.

Predictive metabolites for incident myocardial infarction: a two-step meta-analysis of individual patient data from six cohorts comprising 7897 individuals from the COnsortium of METabolomics Studies

AIMS

Myocardial infarction (MI) is a major cause of death and disability worldwide. Most metabolomics studies investigating metabolites predicting MI are limited by the participant number and/or the demographic diversity. We sought to identify biomarkers of incident MI in the COnsortium of METabolomics Studies.

METHODS AND RESULTS

We included 7897 individuals aged on average 66 years from six intercontinental cohorts with blood metabolomic profiling (n = 1428 metabolites, of which 168 were present in at least three cohorts with over 80% prevalence) and MI information (1373 cases). We performed a two-stage individual patient data meta-analysis. We first assessed the associations between circulating metabolites and incident MI for each cohort adjusting for traditional risk factors and then performed a fixed effect inverse variance meta-analysis to pull the results together. Finally, we conducted a pathway enrichment analysis to identify potential pathways linked to MI. On meta-analysis, 56 metabolites including 21 lipids and 17 amino acids were associated with incident MI after adjusting for multiple testing (false discovery rate < 0.05), and 10 were novel. The largest increased risk was observed for the carbohydrate mannitol/sorbitol {hazard ratio [HR] [95% confidence interval (CI)] = 1.40 [1.26-1.56], P < 0.001}, whereas the largest decrease in risk was found for glutamine [HR (95% CI) = 0.74 (0.67-0.82), P < 0.001]. Moreover, the identified metabolites were significantly enriched (corrected P < 0.05) in pathways previously linked with cardiovascular diseases, including aminoacyl-tRNA biosynthesis.

CONCLUSIONS

In the most comprehensive metabolomic study of incident MI to date, 10 novel metabolites were associated with MI. Metabolite profiles might help to identify high-risk individuals before disease onset. Further research is needed to fully understand the mechanisms of action and elaborate pathway findings.

Metabolomics Changes in Meat and Subcutaneous Fat of Male Cattle Submitted to Fetal Programming

This study investigated changes in meat and subcutaneous fat metabolomes and possible metabolic pathways related to prenatal nutrition in beef cattle. For this purpose, 18 Nellore bulls were used for meat sampling and 15 for fat sampling. The nutritional treatments during the gestation were: NP-not programmed or control, without protein-energy supplementation; PP-partially programmed, with protein-energy supplementation (0.3% of body weight (BW)) only in the final third of pregnancy; and FP-full programming, with protein-energy supplementation (0.3% of BW) during the entire pregnancy. The meat and fat samples were collected individually 24 h after slaughter, and the metabolites were extracted using a combination of chemical reagents and mechanical processes and subsequently quantified using liquid chromatography or flow injection coupled to mass spectrometry. The data obtained were submitted to principal component analysis (PCA), analysis of variance (ANOVA), and functional enrichment analysis, with a significance level of 5%. The PCA showed an overlap between the treatments for both meat and fat. In meat, 25 metabolites were statistically different between treatments (p ≤ 0.05), belonging to four classes (glycerophospholipids, amino acids, sphingolipids, and biogenic amine). In fat, 10 significant metabolites (p ≤ 0.05) were obtained in two classes (phosphatidylcholine and lysophosphatidylcholine). The functional enrichment analysis showed alterations in the aminoacyl-tRNA pathway in meat (p = 0.030); however, there was no pathway enriched for fat. Fetal programming influenced the meat and fat metabolomes and the aminoacyl-tRNA metabolic pathway, which is an important candidate for the biological process linked to meat quality and related to fetal programming in beef cattle.

Machine learning-based biomarker profile derived from 4210 serially measured proteins predicts clinical outcome of patients with heart failure

Aims

Risk assessment tools are needed for timely identification of patients with heart failure (HF) with reduced ejection fraction (HFrEF) who are at high risk of adverse events. In this study, we aim to derive a small set out of 4210 repeatedly measured proteins, which, along with clinical characteristics and established biomarkers, carry optimal prognostic capacity for adverse events, in patients with HFrEF.

Methods and results

In 382 patients, we performed repeated blood sampling (median follow-up: 2.1 years) and applied an aptamer-based multiplex proteomic approach. We used machine learning to select the optimal set of predictors for the primary endpoint (PEP: composite of cardiovascular death, heart transplantation, left ventricular assist device implantation, and HF hospitalization). The association between repeated measures of selected proteins and PEP was investigated by multivariable joint models. Internal validation (cross-validated c-index) and external validation (Henry Ford HF PharmacoGenomic Registry cohort) were performed. Nine proteins were selected in addition to the MAGGIC risk score, N-terminal pro-hormone B-type natriuretic peptide, and troponin T: suppression of tumourigenicity 2, tryptophanyl-tRNA synthetase cytoplasmic, histone H2A Type 3, angiotensinogen, deltex-1, thrombospondin-4, ADAMTS-like protein 2, anthrax toxin receptor 1, and cathepsin D. N-terminal pro-hormone B-type natriuretic peptide and angiotensinogen showed the strongest associations [hazard ratio (95% confidence interval): 1.96 (1.17-3.40) and 0.66 (0.49-0.88), respectively]. The multivariable model yielded a c-index of 0.85 upon internal validation and c-indices up to 0.80 upon external validation. The c-index was higher than that of a model containing established risk factors (P = 0.021).

Conclusion

Nine serially measured proteins captured the most essential prognostic information for the occurrence of adverse events in patients with HFrEF, and provided incremental value for HF prognostication beyond established risk factors. These proteins could be used for dynamic, individual risk assessment in a prospective setting. These findings also illustrate the potential value of relatively 'novel' biomarkers for prognostication.

Clinical Trial Registration

https://clinicaltrials.gov/ct2/show/NCT01851538?term=nCT01851538&draw=2&rank=1 24.

A metabolomics-based analysis of the metabolic pathways associated with the regulation of branched-chain amino acids in rats fed a high-fructose diet

Previous studies have shown that the elevated levels of circulating branched-chain amino acids (BCAAs) are associated with the development of insulin resistance and its complications, including obesity, type 2 diabetes, cardiovascular disease and some cancers. However, animal models that can mimic the metabolic state of chronically elevated BCAAs in humans are rare. Therefore, the aim of this study was to establish the above animal model and analyse the metabolic changes associated with high BCAA levels. Sixteen 8-week-old Sprague-Dawley (SD) rats were randomly divided into two groups and given either a high fructose diet or a normal diet. BCAA levels as well as blood glucose and lipid levels were measured at different time points of feeding. The mRNA expression levels of two key enzymes of BCAA catabolism, ACAD (acyl-CoA dehydrogenase) and BCKDH (branched-chain α-keto acid dehydrogenase), were measured by qPCR, and the protein expression levels of these two enzymes were analysed by immunohistochemistry. Finally, the metabolite expression differences between the two groups were analysed by Q300 metabolomics technology. Our study confirms that defects in the catabolic pathways of BCAAs lead to increased levels of circulating BCAAs, resulting in disorders of glucose and lipid metabolism characterized by insulin resistance by affecting metabolic pathways associated with amino acids and bile acids.

Mutations in DARS2 result in global dysregulation of mRNA metabolism and splicing

Leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL) is a rare neurological disorder caused by the mutations in the DARS2 gene, which encodes the mitochondrial aspartyl-tRNA synthetase. The objective of this study was to understand the impact of DARS2 mutations on cell processes through evaluation of LBSL patient stem cell derived cerebral organoids and neurons. We generated human cerebral organoids (hCOs) from induced pluripotent stem cells (iPSCs) of seven LBSL patients and three healthy controls using an unguided protocol. Single cells from 70-day-old hCOs were subjected to SMART-seq2 sequencing and bioinformatic analysis to acquire high-resolution gene and transcript expression datasets. Global gene expression analysis demonstrated dysregulation of a number of genes involved in mRNA metabolism and splicing processes within LBSL hCOs. Importantly, there were distinct and divergent gene expression profiles based on the nature of the DARS2 mutation. At the transcript level, pervasive differential transcript usage and differential spliced exon events that are involved in protein translation and metabolism were identified in LBSL hCOs. Single-cell analysis of DARS2 (exon 3) showed that some LBSL cells exclusively express transcripts lacking exon 3, indicating that not all LBSL cells can benefit from the "leaky" nature common to splice site mutations. At the gene- and transcript-level, we uncovered that dysregulated RNA splicing, protein translation and metabolism may underlie at least some of the pathophysiological mechanisms in LBSL. To confirm hCO findings, iPSC-derived neurons (iNs) were generated by overexpressing Neurogenin 2 using lentiviral vector to study neuronal growth, splicing of DARS2 exon 3 and DARS2 protein expression. Live cell imaging revealed neuronal growth defects of LBSL iNs, which was consistent with the finding of downregulated expression of genes related to neuronal differentiation in LBSL hCOs. DARS2 protein was downregulated in iNs compared to iPSCs, caused by increased exclusion of exon 3. The scope and complexity of our data imply that DARS2 is potentially involved in transcription regulation beyond its canonical role of aminoacylation. Nevertheless, our work highlights transcript-level dysregulation as a critical, and relatively unexplored, mechanism linking genetic data with neurodegenerative disorders.

Metabolomic analysis reveals the metabolic disturbance in aortic dissection: Subtype difference and accurate diagnosis

BACKGROUND AND AIMS

Aortic dissection (AD), a severe clinical emergency with high mortality, is easily misdiagnosed as are other cardiovascular diseases. This study aimed at discovering plasma metabolic markers with the potential to diagnose AD and clarifying the metabolic differences between two subtypes of AD.

METHODS AND RESULTS

To facilitate the diagnosis of AD, we investigated the plasma metabolic profile by metabolomic approach. A total 482 human subjects were enrolled in the study: 80 patients with AD (50 with Stanford type A and 30 with Stanford type B), 198 coronary artery disease (CAD) patients, and 204 healthy individuals. Plasma samples were submitted to targeted metabolomic analysis. The partial least-squares discriminant analysis models were constructed to illustrate clear discrimination of AD patients with CAD patients and healthy control. Subsequently, the metabolites that were clinically relevant to the disturbances in AD were identified. Twenty metabolites induced the separation of AD patients and healthy control, 9 of which caused the separation of CAD patients and healthy control. There are 11 metabolites specifically down-regulated in AD group. Subgroup analysis showed that the levels of glycerol and uridine were dramatically lower in the plasma of patients with Stanford type A AD than those in the healthy control or Stanford type B AD groups.

CONCLUSION

This study characterized metabolomic profiles specifically associated with the pathogenesis and development of AD. The findings of this research may potentially lead to earlier diagnosis and treatment of AD.

Comprehensive Analysis of Microbiome, Metabolome, and Transcriptome Revealed the Mechanisms of Intestinal Injury in Rainbow Trout under Heat Stress

Global warming is one of the most common environmental challenges faced by cold-water fish farming. Intestinal barrier function, gut microbiota, and gut microbial metabolites are significantly altered under heat stress, posing serious obstacles to the healthy artificial culture of rainbow trout. However, the molecular mechanisms underlying intestinal injury in rainbow trout under heat stress remain unclear. In the present study, the optimal growth temperature for rainbow trout (16 °C) was used for the control group, and the maximum temperature tolerated by rainbow trout (24 °C) was used for the heat stress group, which was subjected to heat stress for 21 days. The mechanism of intestinal injury in rainbow trout under heat stress was explored by combining animal histology, 16S rRNA gene amplicon sequencing, ultra-high performance liquid chromatography-mass spectrometry, and transcriptome sequencing. The results showed that the antioxidant capacity of rainbow trout was enhanced under heat stress, the levels of stress-related hormones were significantly increased, and the relative expression of genes related to heat stress proteins was significantly increased, indicating that the heat stress model of rainbow trout was successfully established. Secondly, the intestinal tract of rainbow trout showed inflammatory pathological characteristics under heat stress, with increased permeability, activation of the inflammatory factor signaling pathway, and increased relative expression of inflammatory factor genes, suggesting that the intestinal barrier function was impaired. Thirdly, heat stress caused an imbalance of intestinal commensal microbiota and changes in intestinal metabolites in rainbow trout, which participated in the stress response mainly by affecting lipid metabolism and amino acid metabolism. Finally, heat stress promoted intestinal injury in rainbow trout by activating the peroxisome proliferator-activated receptor-α signaling pathway. These results not only expand the understanding of fish stress physiology and regulation mechanisms, but also provide a scientific basis for healthy artificial culture and the reduction of rainbow trout production costs.

Recessive aminoacyl-tRNA synthetase disorders: lessons learned from in vivo disease models

Protein synthesis is a fundamental process that underpins almost every aspect of cellular functioning. Intriguingly, despite their common function, recessive mutations in aminoacyl-tRNA synthetases (ARSs), the family of enzymes that pair tRNA molecules with amino acids prior to translation on the ribosome, cause a diverse range of multi-system disorders that affect specific groups of tissues. Neurological development is impaired in most ARS-associated disorders. In addition to central nervous system defects, diseases caused by recessive mutations in cytosolic ARSs commonly affect the liver and lungs. Patients with biallelic mutations in mitochondrial ARSs often present with encephalopathies, with variable involvement of peripheral systems. Many of these disorders cause severe disability, and as understanding of their pathogenesis is currently limited, there are no effective treatments available. To address this, accurate in vivo models for most of the recessive ARS diseases are urgently needed. Here, we discuss approaches that have been taken to model recessive ARS diseases in vivo, highlighting some of the challenges that have arisen in this process, as well as key results obtained from these models. Further development and refinement of animal models is essential to facilitate a better understanding of the pathophysiology underlying recessive ARS diseases, and ultimately to enable development and testing of effective therapies.

FARSB serves as a novel hypomethylated and immune cell infiltration related prognostic biomarker in hepatocellular carcinoma

PURPOSE

Hepatocellular carcinoma (HCC) is a prevalent tumor with high morbidity, and an unfavourable prognosis. FARSB is an aminoacyl tRNA synthase, and plays a key role in protein synthesis in cells. Furthermore, previous reports have indicated that FARSB is overexpressed in gastric tumor tissues and is associated with a poor prognosis and tumorigenesis. However, the function of FARSB in HCC has not been studied.

RESULTS

The results showed that FARSB mRNA and protein levels were upregulated in HCC and were closely related to many clinicopathological characteristics. Besides, according to multivariate Cox analysis, high FARSB expression was linked with a shorter survival time in HCC and may be an independent prognostic factor. In addition, the FARSB promoter methylation level was negatively associated with the expression of FARSB. Furthermore, enrichment analysis showed that FARSB was related to the cell cycle. And TIMER analysis revealed that the FARSB expression was closely linked to tumor purity and immune cell infiltration. The TCGA and ICGC data analysis suggested that FARSB expression is greatly related to m6A modifier related genes. Potential FARSB-related ceRNA regulatory networks were also constructed. What's more, based on the FARSB-protein interaction network, molecular docking models of FARSB and RPLP1 were constructed. Finally, drug susceptibility testing revealed that FARSB was susceptible to 38 different drugs or small molecules.

CONCLUSIONS

FARSB can serve as a prognostic biomarker for HCC and provide clues about immune infiltration, and m6A modification.

Protective effect and mechanism of ginsenoside Rg2 on atherosclerosis

Background

Ginsenoside Rg2 (Rg2) has a variety of pharmacological activities and provides benefits during inflammation, cancer, and other diseases. However, there are no reports about the relationship between Rg2 and atherosclerosis.

Methods

We used 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) to detect the cell viability of Rg2 in vascular smooth muscle cells (VSMCs) and human umbilical vein endothelial cells (HUVECs). The expression of inflammatory factors in HUVECs and the expression of phenotypic transformation-related marker in VSMCs were detected at mRNA levels. Western blot method was used to detect the expression of inflammation pathways and the expression of phenotypic transformation at the protein levels. The rat carotid balloon injury model was performed to explore the effect of Rg2 on inflammation and phenotypic transformation in vivo.

Results

Rg2 decreased the expression of inflammatory factors induced by lipopolysaccharide in HUVECs-without affecting cell viability. These events depend on the blocking regulation of NF-κB and p-ERK signaling pathway. In VSMCs, Rg2 can inhibit the proliferation, migration, and phenotypic transformation of VSMCs induced by platelet derived growth factor-BB (PDGF-BB)-which may contribute to its anti-atherosclerotic role. In rats with carotid balloon injury, Rg2 can reduce intimal proliferation after injury, regulate the inflammatory pathway to reduce inflammatory response, and also suppress the phenotypic transformation of VSMCs.

Conclusion

These results suggest that Rg2 can exert its anti-atherosclerotic effect at the cellular level and animal level, which provides a more sufficient basis for ginseng as a functional dietary regulator.

Mutations in DARS2 result in global dysregulation of mRNA metabolism and splicing

Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) is a rare neurological disorder caused by the mutations in the DARS2 gene, which encodes the mitochondrial aspartyl-tRNA synthetase. The objective of this study was to understand the impact of DARS2 mutations on cell processes through evaluation of LBSL patient stem cell derived cerebral organoids and neurons. We generated human cerebral organoids (hCOs) from induced pluripotent stem cells (iPSCs) of seven LBSL patients and three healthy controls using an unguided protocol. Single cells from 70-day-old hCOs underwent SMART-seq2 sequencing and multiple bioinformatic analysis tools were applied to high-resolution gene and transcript expression analyses. To confirm hCO findings, iPSC-derived neurons (iNs) were generated by overexpressing Neurogenin 2 using lentiviral vector to study neuronal growth, splicing of DARS2 exon 3 and DARS2 protein expression. Global gene expression analysis demonstrated dysregulation of a number of genes involved in mRNA metabolism and splicing processes within LBSL hCOs. Importantly, there were distinct and divergent gene expression profiles based on the nature of the DARS2 mutation. At the transcript level, pervasive differential transcript usage and differential spliced exon events that are involved in protein translation and metabolism were identified in LBSL hCOs. Single-cell analysis of DARS2 (exon 3) showed that some LBSL cells exclusively express transcripts lacking exon 3, indicating that not all LBSL cells can benefit from the "leaky" nature common to splice site mutations. Live cell imaging revealed neuronal growth defects of LBSL iNs, which was consistent with the finding of downregulated expression of genes related to neuronal differentiation in LBSL hCOs. DARS2 protein was downregulated in iNs compared to iPSCs, caused by increased exclusion of exon 3. At the gene- and transcript-level, we uncovered that dysregulated RNA splicing, protein translation and metabolism may underlie at least some of the pathophysiological mechanisms in LBSL. The scope and complexity of our data imply that DARS2 is potentially involved in transcription regulation beyond its canonical role of aminoacylation. Nevertheless, our work highlights transcript-level dysregulation as a critical, and relatively unexplored, mechanism linking genetic data with neurodegenerative disorders.

Metabolomics profile and 10-year atherosclerotic cardiovascular disease (ASCVD) risk score

Background

The intermediate metabolites associated with the development of atherosclerotic cardiovascular disease (ASCVD) remain largely unknown. Thus, we conducted a large panel of metabolomics profiling to identify the new candidate metabolites that were associated with 10-year ASCVD risk.

Methods

Thirty acylcarnitines and twenty amino acids were measured in the fasting plasma of 1,102 randomly selected individuals using a targeted FIA-MS/MS approach. The 10-year ASCVD risk score was calculated based on 2013 ACC/AHA guidelines. Accordingly, the subjects were stratified into four groups: low-risk (n = 620), borderline-risk (n = 110), intermediate-risk (n = 225), and high-risk (n = 147). 10 factors comprising collinear metabolites were extracted from principal component analysis.

Results

C₄DC, C_8:1, C₁₆OH, citrulline, histidine, alanine, threonine, glycine, glutamine, tryptophan, phenylalanine, glutamic acid, arginine, and aspartic acid were significantly associated with the 10-year ASCVD risk score (p-values ≤ 0.044). The high-risk group had higher odds of factor 1 (12 long-chain acylcarnitines, OR = 1.103), factor 2 (5 medium-chain acylcarnitines, OR = 1.063), factor 3 (methionine, leucine, valine, tryptophan, tyrosine, phenylalanine, OR = 1.074), factor 5 (6 short-chain acylcarnitines, OR = 1.205), factor 6 (5 short-chain acylcarnitines, OR = 1.229), factor 7 (alanine, proline, OR = 1.343), factor 8 (C_18:2OH, glutamic acid, aspartic acid, OR = 1.188), and factor 10 (ornithine, citrulline, OR = 1.570) compared to the low-risk ones; the odds of factor 9 (glycine, serine, threonine, OR = 0.741), however, were lower in the high-risk group. "D-glutamine and D-glutamate metabolism", "phenylalanine, tyrosine, and tryptophan biosynthesis", and "valine, leucine, and isoleucine biosynthesis" were metabolic pathways having the highest association with borderline/intermediate/high ASCVD events, respectively.

Conclusions

Abundant metabolites were found to be associated with ASCVD events in this study. Utilization of this metabolic panel could be a promising strategy for early detection and prevention of ASCVD events.

Metagenomic and metabolomic analyses show correlations between intestinal microbiome diversity and microbiome metabolites in ob/ob and ApoE−/− mice

Obesity and atherosclerosis are the most prevalent metabolic diseases. ApoE^−/− and ob/ob mice are widely used as models to study the pathogenesis of these diseases. However, how gut microbes, gut bacteriophages, and metabolites change in these two disease models is unclear. Here, we used wild-type C57BL/6J (Wt) mice as normal controls to analyze the intestinal archaea, bacteria, bacteriophages, and microbial metabolites of ob/ob and ApoE^−/− mice through metagenomics and metabolomics. Analysis of the intestinal archaea showed that the abundances of Methanobrevibacter and Halolamina were significantly increased and decreased, respectively, in the ob/ob group compared with those in the Wt and ApoE^−/− groups (p < 0.05). Compared with those of the Wt group, the relative abundances of the bacterial genera Enterorhabdus, Alistipes, Bacteroides, Prevotella, Rikenella, Barnesiella, Porphyromonas, Riemerella, and Bifidobacterium were significantly decreased (p < 0.05) in the ob/ob mice, and the relative abundance of Akkermansia was significantly decreased in the ApoE^−/− group. The relative abundances of A. muciniphila and L. murinus were significantly decreased and increased, respectively, in the ob/ob and ApoE^−/− groups compared with those of the Wt group (p < 0.05). Lactobacillus_ prophage_ Lj965 and Lactobacillus _ prophage _ Lj771 were significantly more abundant in the ob/ob mice than in the Wt mice. Analysis of the aminoacyl-tRNA biosynthesis metabolic pathway revealed that the enriched compounds of phenylalanine, glutamine, glycine, serine, methionine, valine, alanine, lysine, isoleucine, leucine, threonine, tryptophan, and tyrosine were downregulated in the ApoE^−/− mice compared with those of the ob/ob mice. Aminoacyl-tRNA synthetases are considered manifestations of metabolic diseases and are closely associated with obesity, atherosclerosis, and type 2 diabetes. These data offer new insight regarding possible causes of these diseases and provide a foundation for studying the regulation of various food nutrients in metabolic disease models.

Exploration of the amino acid metabolic signature in anthracycline-induced cardiotoxicity using an optimized targeted metabolomics approach based on UPLC-MS/MS

Although anthracyclines improve the long-term survival rate of patients with cancer, severe and irreversible myocardial damage limits their clinical application. Amino acid (AA) metabolism in cardiomyocytes can be altered under pathological conditions. Therefore, exploring the AA metabolic signature in anthracycline-induced cardiotoxicity (AIC) is important for identifying novel mechanisms. We established mouse and cellular models of Adriamycin (ADR)-induced cardiac injury. We observed a decreased expression of troponins I (cTnI) after ADR treatment and ADR accelerated the degradation of cTnI, implying that AA metabolism could be altered in AIC. Using a targeted AA metabolomics approach based on ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), the AA metabolic signatures in the sera of AIC mice and supernatant samples of ADR-treated H9c2 cardiomyocytes were analyzed. The levels of 14 AA metabolites were altered in ADR-treated mice (p < 0.05). Via bioinformatics analysis, we identified nine differential AA metabolites in mice and five differential AA metabolites in ADR-treated H9c2 cardiomyocytes. Three AAs with increased levels (L-glutamate, L-serine, and L-tyrosine) overlapped in the two models, suggesting a possible mechanism of AA metabolic impairment during AIC. The metabolic pathways perturbed by AIC involved aminoacyl-tRNA biosynthesis and alanine, aspartate, and glutamate metabolism. Our data suggests that ADR perturbed AA metabolism in AIC models. Moreover, the targeted AA metabolomics approach based on UPLC-MS/MS can be a unique platform to provide new clues for the prevention and treatment of AIC.

Comprehensive analysis of microbiome, metabolome and transcriptome revealed the mechanisms of Moringa oleifera polysaccharide on preventing ulcerative colitis

This study aimed to investigate the protective effect of Moringa oleifera polysaccharide (MOP) on ulcerative colitis (UC) and explore its mechanism through the combined analysis of microbiome, metabolome and transcriptome. A UC model in mice was established using dextran sulphate sodium. After a 21-day experiment, results showed that MOP could inhibit the weight loss and disease activity index in UC mice. The intervention of MOP decreased the expression of inflammatory cytokines and promoted the secretion of tight junctions. MOP could promote the growth of probiotics such as Lachnospiraceae_NK4A136, Intestinimonas and Bifidobacterium in UC mice. The results of metabolomic and transcriptomic analysis indicated that MOP could regulated the metabolism of polyunsaturated fatty acid and PPAR, TLR and TNF signalling pathways might play important roles in the process. Altogether, MOP could be used as a functional food to prevent UC.

Doxorubicin-Induced Cardiotoxicity May Be Alleviated by Bone Marrow Mesenchymal Stem Cell-Derived Exosomal lncRNA via Inhibiting Inflammation

Purpose

To explore the therapeutic mechanism of bone marrow mesenchymal stem cells derived exosomes (BMSC-Exos) for doxorubicin (DOX)-induced cardiotoxicity (DIC) and identify the long noncoding RNAs’ (lncRNAs’) anti-inflammation function derived by BMSC-Exos.

Materials and Methods

High-throughput sequencing and transcriptome bioinformatics analysis of lncRNA were performed between DOX group and BEC (bone marrow mesenchymal stem cells derived exosomes coculture) group. Elevated lncRNA (ElncRNA) in the cardiomyocytes of BEC group compared with DOX group were confirmed. Based on the location and co-expression relationship between ElncRNA and its target genes, we predicted two target genes of ElncRNA, named cis_targets and trans_targets. The target genes were analyzed by enrichment analyses. Then, we identified the key cellular biological pathways regulating DIC. Experiments were performed to verify the therapeutic effects of exosomes and the origin of lncRNAs in vitro and in vivo.

Results

Three hundred and one lncRNAs were differentially expressed between DOX and BEC groups (fold change >1.5 and p < 0.05), of which 169 lncRNAs were elevated in the BEC group compared with the DOX group. GO enrichment analysis of target genes of ElncRNAs showed that they were predominantly involved in inflammation-associated processes. KEGG analysis indicated that their regulatory pathways were mainly involved in oxidative stress-induced inflammation and proliferation of cardiomyocyte. The verification experiments in vitro showed that the oxidative stress and cell deaths were decreased in BEC groups. Moreover, from the top 10 ElncRNAs identified in the sequencing results, MSTRG.98097.4 and MSTRG.58791.2 were both decreased in the DOX group and elevated in BEC group. While in verification experiments in vivo, only the expression of MSTRG.58791.2 is consistent with the result in vitro.

Conclusion

Our results show that ElncRNA, MSTRG.58791.2, is possibly secreted by the BMSC-Exos and able to alleviate DIC by suppressing inflammatory response and inflammation-related cell death.

miR-564: A potential regulator of vascular smooth muscle cells and therapeutic target for aortic dissection

BACKGROUND

Aortic dissection (AD) is a lethal cardiac disorder and one of the most concerning cardiovascular diseases (CVDs). Increasing evidence indicates that human aortic vascular smooth muscle cells (VSMCs) play a crucial role in the pathogenesis of AD, especially related to phenotypic transformation. And notablely, the development of AD is also accompanied by inflammation.

METHODS

By using quantitative real-time PCR and fluorescence in situ hybridization (FISH), we detected the expression levels of miR-564 in vitro and in vivo. The effects of miR-564 proliferation and migration were investigated in VSMCs. The downstream targets of miR-564 were found by bioinformatics analyse, and verified in the regulation on VSMCs. An AD murine model was constructed and clinical evaluation was performed to explore the critical roles of miR-564 in vivo. At the same time, the level of inflammation was detected using quantitative real-time PCR and immunofluorescence.

RESULTS

Overexpression of miR-564 inhibited cell proliferation and migration, as well as phenotype switch, with or without platelet-derived growth factor BB (PDGF-BB) treatment, whereas downregulation of miR-564 led to opposite results. Mechanistically, miR-564 directly interacted with the target genes proto-oncogene (SKI) and neurogranin (NRGN) to regulate the biological functions of VSMCs. In particular, animal experiments demonstrated that miR-564 can alleviate the progression of AD mainly through mediating phenotypic swithing and inflammation which was consistent with clinical evaluation.

CONCLUSIONS

Our study identified miR-564 as a significant molecule that attenuates AD progression by inhibiting inflammation and VSMCs proliferation, migration and phenotypic transformation, suggesting that it may be a potential therapeutic target for AD.

The lncRNA Punisher Regulates Apoptosis and Mitochondrial Homeostasis of Vascular Smooth Muscle Cells via Targeting miR-664a-5p and OPA1

Long noncoding RNAs (lncRNAs) are important regulators of various cellular functions. Recent studies have shown that a novel lncRNA termed Punisher is highly expressed in cardiovascular progenitors and has potential role in cardiovascular diseases. However, its role, especially in molecular mechanism, is unclear. In our present study, we observed that Punisher was obviously downregulated in atherosclerotic plaques. Further research proved that it can suppress the apoptosis of VSMCs potentially contributing to the progression of atherosclerosis. Intriguingly, Punisher revealed to regulate mitochondria fission as well as mitochondrial functions induced by hydrogen peroxide (H₂O₂) in VSMCs. Mechanistically, Punisher was further proved to serve as a ceRNA which directly binds to miR-664a-5p and consequently regulates its target OPA1, and finally contributes to the biological function of VSMCs. Particularly, Punisher overexpression distinctly suppressed neointima formation and VSMC apoptosis in vivo. Encouragingly, these results were in accordance with findings obtained with the clinical evaluation of patients with atherosclerosis. Our data provides the significant relationship among OPA1, mitochondrial homeostasis, VSMC apoptosis, and atherosclerosis. And lncRNA Punisher and miR-664a-5p could serve as the novel and potential targets in the diagnosis and treatment of cardiovascular diseases.

Comprehensive profile of circRNAs in formaldehyde induced heart development

Circular RNAs (circRNAs) are a novel type of long non-coding RNAs that can regulate gene expression in heart development and heart disease. However, the expression pattern of circRNAs in congenital heart disease (CHD) induced by formaldehyde exposure is still unknown. We detected circRNAs expression profiles in heart tissue taken from six neonatal rat pups with formaldehyde exposure group and normal group using RNA-sequencing. Results revealed that a total of 54 circRNAs were dysregulated in the formaldehyde exposure group compared to the normal group. Among them, 31 were upregulated and 23 were downregulated (fold change = 2.0, p < 0.0 5). The qRT-qPCR results showed that expressions of 12:628708|632694, 18:77477060|77520779, 5:167486001|167526275 were significantly upregulated, while that of 7:41167312|4116775 and 20:50659751|5068786 were notably downregulated; the expression pattern was consistent with the RNA sequencing data. Bioinformatics analysis shows that the pathogenesis of formaldehyde exposure-induced CHD may involve Hippo-YAP pathway、Notch signaling pathway and other pathways. A key miRNA (rno-miR-665) was identified by constructing a circRNA-miRNA-mRNA co-expression network. In summary, the study illustrated that circRNAs differentially expressed in fetal heart tissues during formaldehyde exposure has potential biological functions and may be a biomarker or therapeutic target for CHD.

Multistage-Responsive Nanocomplexes Attenuate Ulcerative Colitis by Improving the Accumulation and Distribution of Oral Nucleic Acid Drugs in the Colon

Oral gene therapy has emerged as a potential optimal treatment for ulcerative colitis (UC). Nucleic acid drugs possessing versatility can not only inhibit inflammation but realize colon mucosal healing, fulfilling the clinical objective of UC therapy. However, the effective accumulation and distribution of oral nucleic acid drugs in the colon remain a considerable challenge. Furthermore, current delivery systems pay more attention to the accumulation of nucleic acid drugs in the colon, while the distribution of nucleic acid drugs in the colon, which plays a key role in the UC treatment, never catches the attention of researchers. Here, we used miR-320 as a model nucleic acid drug to develop a kind of multistage-responsive nanocomplexes (MSNs) based on polymeric nanocapsules and alginate. MSNs possess the pH responsiveness in the stomach, the enzyme responsiveness in the colonic lumen, and the redox responsiveness in the cytoplasm. In vivo imaging results showed that MSNs reach the colon within 2 h and effectively release miR-320 nanocapsules in the colonic lumen. The nanocapsules can further deliver miR-320 to the submucosal layer and even the muscular layer. Moreover, MSNs decreased the activity of myeloperoxidase and proinflammatory cytokines and exhibited anti-inflammatory activity by inhibiting the phosphorylation of IκBα and AKT, reducing colonic inflammation and enhancing mucosal repair. Therefore, MSNs can successfully alleviate UC by improving the accumulation and distribution of oral nucleic acid drugs in the colon, promoting the clinical translational application of nucleic acid drugs in the treatment of UC.

miR-153-3p Targets βII Spectrin to Regulate Formaldehyde-Induced Cardiomyocyte Apoptosis

Background: Formaldehyde (FA) is ubiquitous in the environment and can be transferred to the fetus through placental circulation, causing miscarriage and congenital heart disease (CHD). Studies have shown that βII spectrin is necessary for cardiomyocyte survival and differentiation, and its loss leads to heart development defects and cardiomyocyte apoptosis. Additionally, previous studies have demonstrated that miRNA is essential in heart development and remodeling. However, whether miRNA regulates FA-induced CHD and cardiomyocyte apoptosis remains unclear. Methods: Using commercially available rat embryonic cardiomyocytes and a rat model of fetal cardiomyocyte apoptosis. Real-time quantitative PCR (RT-qPCR) and Western blot were performed to examine the level of miR-153-3p, βII spectrin, caspase 7, cleaved caspase7, Bax, Bcl-2 expression in embryonic cardiomyocytes and a rat model of fetal cardiomyocyte apoptosis. Apoptotic cell populations were evaluated by flow cytometry and Tunel. Luciferase activity assay and RNA pull-down assay were used to detect the interaction between miR-153-3p and βII spectrin. Masson's trichrome staining detects the degree of tissue fibrosis. Fluorescence in situ hybridization (FISH) and Immunohistochemistry were used to detect the expression of miR-153-3p and βII spectrin in tissues. Results: Using commercially available rat embryonic cardiomyocytes and a rat model of fetal cardiomyocyte apoptosis, our studies indicate that miR-153-3p plays a regulatory role by directly targeting βII spectrin to promote cardiomyocyte apoptosis. miR-153-3p mainly regulates cardiomyocyte apoptosis by regulating the expression of caspase7, further elucidating the importance of apoptosis in heart development. Finally, the results with our animal model revealed that targeting the miR-153-3p/βII spectrin pathway effectively regulated FA-induced damage during heart development. Recovery experiments with miR-153-3p antagomir resulted in the reversal of FA-induced cardiomyocyte apoptosis and fetal cardiac fibrosis. Conclusion: This study investigated the molecular mechanism underpinning the role of βII spectrin in FA-induced CHD and the associated upstream miRNA pathway. The study findings suggest that miR-153-3p may provide a potential target for the clinical diagnosis and treatment of CHD.

The discovery of combined toxicity effects and mechanisms of hexaconazole and arsenic to mice based on untargeted metabolomics

The high detected frequencies of hexaconazole (Hex) and arsenic (As) increased the probabilities of their co-existence in agricultural products. However, the combined toxicity effect and mechanism of action for these two pollutants were still unclear. In this study, an untargeted metabolomics method with ultra high performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS) was developed to monitor the changes of endogenous metabolites and metabolism pathways in mice liver. Our study revealed that significant differences in metabolomics profiles were observed after Hex, As, and Hex+As exposure for 90 d. Hex exposure altered 54 metabolites and 11 pathways significantly which were mainly lipid-related. For As exposure, 63 metabolites and 9 pathways were affected most of which were amino acid-related. Hex+As induced 93 metabolites changes with 34% was lipids and lipid-like molecules and 22% was organic acids and derivatives. Hex+As exposure shared the pathways that altered by Hex and As indicated that the interaction of Hex and As might be independent action. The results of this study could provide an important insight for understanding the mechanism of combined toxicity for Hex and As and be helpful for evaluating their health risk to human.