Integrative Molecular Phenotyping
INTEGRATIVE MOLECULAR
PHENOTYPING
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY

PubMed

Gut microbiota and fecal metabolites in sustained unresponsiveness by oral immunotherapy in school-age children with cow's milk allergy

Fri, 05/01/2024 - 12:00
Allergol Int. 2024 Jan;73(1):126-136. doi: 10.1016/j.alit.2023.10.001. Epub 2023 Nov 1.ABSTRACTBACKGROUND: Oral immunotherapy (OIT) can ameliorate cow's milk allergy (CMA); however, the achievement of sustained unresponsiveness (SU) is challenging. Regarding the pathogenesis of CMA, recent studies have shown the importance of gut microbiota (Mb) and fecal water-soluble metabolites (WSMs), which prompted us to determine the change in clinical and gut environmental factors important for acquiring SU after OIT for CMA.METHODS: We conducted an ancillary cohort study of a multicenter randomized, parallel-group, delayed-start design study on 32 school-age children with IgE-mediated CMA who underwent OIT for 13 months. We defined SU as the ability to consume cow's milk exceeding the target dose in a double-blind placebo-controlled food challenge after OIT followed by a 2-week-avoidance. We longitudinally collected 175 fecal specimens and clustered the microbiome and metabolome data into 29 Mb- and 12 WSM-modules.RESULTS: During OIT, immunological factors improved in all participants. However, of the 32 participants, 4 withdrew because of adverse events, and only 7 were judged SU. Gut environmental factors shifted during OIT, but only in the beginning, and returned to the baseline at the end. Of these factors, milk- and casein-specific IgE and the Bifidobacterium-dominant module were associated with SU (milk- and casein-specific IgE; OR for 10 kUA/L increments, 0.67 and 0.66; 95%CI, 0.41-0.93 and 0.42-0.90; Bifidobacterium-dominant module; OR for 0.01 increments, 1.40; 95%CI, 1.10-2.03), and these associations were observed until the end of OIT.CONCLUSIONS: In this study, we identified the clinical and gut environmental factors associated with SU acquisition in CM-OIT.PMID:38182280 | DOI:10.1016/j.alit.2023.10.001

Oleander attenuates hepatic inflammation in a TLR4-independent manner and by favorable modulation of hepatocellular global metabolome that supports cytoprotection

Fri, 05/01/2024 - 12:00
J Ethnopharmacol. 2024 Jan 3:117717. doi: 10.1016/j.jep.2024.117717. Online ahead of print.ABSTRACTETHNOPHARMACOLOGICAL RELEVANCE: Nerium oleander is used to treat liver-associated chronic metabolic diseases in traditional medicinal systems across the globe. The hepatoprotective effects of oleander are mentioned in Indian and Chinese traditional medicinal literature.AIM OF THE STUDY: The present study aimed to investigate the cellular mechanisms behind the hepatoprotective effects of a non-toxic dose of oleander (NO).MATERIALS AND METHODS: The hepatoprotective effects of NO were tested against lipopolysaccharide (LPS)-treated HepG2 cells. Oxidative stress response was studied using cellular enzymatic assays, and gene expression was analyzed using qRT-PCR. HepG2 cells were pretreated with TAK-242 (pharmacological inhibitor of TLR4) to decipher the anti-inflammatory mechanisms of NO. Cell-free metabolites were analyzed using GCMS and were subjected to pathway enrichment analysis.RESULTS: NO reduced systemic inflammation, serum lipid peroxidation byproducts, and glucose without affecting serum transaminase levels and hepatic histopathological features. NO attenuated the inflammation-induced loss of antioxidant enzyme activities and mRNA expressions of toll-like receptor-4 (TLR4)/nuclear factor κβ (NFκβ)-dependent inflammatory genes. In TAK-242 pretreated cells, LPS was unable to induce inflammatory and oxidative responses. However, NO treatment in TAK-242 pretreated cells with LPS stimulation further reduced the signs of inflammation and improved hepatoprotective activities. A comparative analysis of the intracellular global metabolome from HepG2 cells with and without NO treatment indicated NO-mediated favorable modulation of intracellular metabolic pathways that support cytoprotective activities.CONCLUSION: NO protects HepG2 cells from LPS-induced oxidative and inflammatory injury. The hepatoprotective effects of NO are mediated by a TLR4-independent process and through a favorable modulation of the intracellular global metabolome that supports cytoprotection.PMID:38181937 | DOI:10.1016/j.jep.2024.117717

Discovery of novel diagnostic biomarkers for Sjögren-Larsson syndrome by untargeted lipidomics

Fri, 05/01/2024 - 12:00
Biochim Biophys Acta Mol Cell Biol Lipids. 2024 Jan 3:159447. doi: 10.1016/j.bbalip.2023.159447. Online ahead of print.ABSTRACTAIM: Sjögren-Larsson syndrome (SLS) is a rare neurometabolic disorder that mainly affects brain, eye and skin and is caused by deficiency of fatty aldehyde dehydrogenase. Our recent finding of a profoundly disturbed brain tissue lipidome in SLS prompted us to search for similar biomarkers in plasma as no functional test in blood is available for SLS.METHODS AND RESULTS: We performed plasma lipidomics and used a newly developed bioinformatics tool to mine the untargeted part of the SLS plasma and brain lipidome to search for SLS biomarkers. Plasma lipidomics showed disturbed ether lipid metabolism in known lipid classes. Untargeted lipidomics of both plasma and brain (white and grey matter) uncovered two new endogenous lipid classes highly elevated in SLS. The first biomarker group were alkylphosphocholines/ethanolamines containing different lengths of alkyl-chains where some alkylphosphocholines were > 600-fold elevated in SLS plasma. The second group of biomarkers were a set of 5 features of unknown structure. Fragmentation studies suggested that they contain ubiquinol and phosphocholine and one feature was also found as a glucuronide conjugate in plasma. The plasma features were highly distinctive for SLS with levels >100-1000-fold the level in controls, if present at all. We speculate on the origin of the alkylphosphocholines/ethanolamines and the nature of the ubiquinol-containing metabolites.CONCLUSIONS: The metabolites identified in this study represent novel endogenous lipid classes thus far unknown in humans. They represent the first plasma metabolite SLS-biomarkers and may also yield more insight into SLS pathophysiology.PMID:38181883 | DOI:10.1016/j.bbalip.2023.159447

Bariatric surgery, through beneficial effects on underlying mechanisms, improves cardiorenal and liver metabolic risk over an average of ten years of observation: a longitudinal and a case-control study

Fri, 05/01/2024 - 12:00
Metabolism. 2024 Jan 3:155773. doi: 10.1016/j.metabol.2023.155773. Online ahead of print.ABSTRACTBACKGROUND: Bariatric surgery has long-term beneficial effects on body weight and metabolic status, but there is an apparent lack of comprehensive cardiometabolic, renal, liver, and metabolomic/lipidomic panels, whereas the underlying mechanisms driving the observed postoperative ameliorations are still poorly investigated. We aimed to study the long-term effects of bariatric surgery on metabolic profile, cardiorenal and liver outcomes in association with underlying postoperative gut hormone adaptations.METHODS: 28 individuals who underwent bariatric surgery [17 sleeve gastrectomy (SG), 11 Roux-en-Y gastric bypass (RYGB)] were followed up 3, 6 and 12 and at 10 years following surgery. Participants at 10 years were cross-sectionally compared with an age-, gender- and adiposity-matched group of non-operated individuals (n = 9) and an age-matched pilot group of normal-weight individuals (n = 4).RESULTS: There were durable effects of surgery on body weight and composition, with an increase of lean mass percentage persisting despite some weight regain 10 years postoperatively. The improvements in metabolic and lipoprotein profiles, cardiometabolic risk markers, echocardiographic and cardiorenal outcomes persisted over the ten-year observation period. The robust improvements in insulin resistance, adipokines, activin/follistatin components and postprandial gastrointestinal peptide levels persisted 10 years postoperatively. These effects were largely independent of surgery type, except for a lasting reduction of ghrelin in the SG subgroup, and more pronounced increases in proglucagon products, mainly glicentin and oxyntomodulin, and in the cardiovascular risk marker Trimethylamine-N-oxide (TMAO) within the RYGB subgroup. Despite similar demographic and clinical features, participants 10 years after surgery showed a more favorable metabolic profile compared with the control group, in conjunction with a dramatic increase of postprandial proglucagon product secretion.CONCLUSIONS: We demonstrate that cardiorenal and metabolic benefits of bariatric surgery remain robust and largely unchanged ten years postoperatively and are associated with durable effects on gastrointestinal- muscle- and adipose tissue-secreted hormones.TRIAL REGISTRATION: ClinicalTrials.gov: NCT04170010.PMID:38181882 | DOI:10.1016/j.metabol.2023.155773

Aldehyde Dehydrogenase 2 Serves as a Key Cardiometabolic Adaptation Regulator in Response to Plateau Hypoxia in Mice

Fri, 05/01/2024 - 12:00
Transl Res. 2024 Jan 3:S1931-5244(23)00204-9. doi: 10.1016/j.trsl.2023.12.003. Online ahead of print.ABSTRACTHigh-altitude heart disease (HAHD) is a complex pathophysiological condition related to systemic hypobaric hypoxia in response to transitioning to high altitude. Hypoxia can cause myocardial metabolic dysregulation, leading to an increased risk of heart failure and sudden cardiac death. Aldehyde dehydrogenase 2 (ALDH2) could regulate myocardial energy metabolism and plays a protective role in various cardiovascular diseases. This study aims to determine the effects of plateau hypoxia (PH) on cardiac metabolism and function, investigate the associated role of ALDH2, and explore potential therapeutic targets. We discovered that PH significantly reduced survival rate and cardiac function. These effects were exacerbated by ALDH2 deficiency. PH also caused a shift in the myocardial fuel source from fatty acids to glucose; ALDH2 deficiency impaired this adaptive metabolic shift. Untargeted/targeted metabolomics and transmission electron microscopy revealed that ALDH2 deficiency promoted myocardial fatty-acid deposition, leading to enhanced fatty-acid transport, lipotoxicity and mitochondrial dysfunction. Furthermore, results showed that ALDH2 attenuated PH-induced impairment of adaptive metabolic programs through 4-HNE/CPT1 signaling, and the CPT1 inhibitor etomoxir significantly ameliorated ALDH2 deficiency-induced cardiac impairment and improved survival in PH mice. Together, our data reveal ALDH2 acts as a key cardiometabolic adaptation regulator in response to PH. CPT1 inhibitor, etomoxir, may attenuate ALDH2 deficiency-induced effects and improved cardiac function in response to PH.PMID:38181846 | DOI:10.1016/j.trsl.2023.12.003

Human trials exploring anti-aging medicines

Fri, 05/01/2024 - 12:00
Cell Metab. 2023 Dec 22:S1550-4131(23)00458-8. doi: 10.1016/j.cmet.2023.12.007. Online ahead of print.ABSTRACTHere, we summarize the current knowledge on eight promising drugs and natural compounds that have been tested in the clinic: metformin, NAD+ precursors, glucagon-like peptide-1 receptor agonists, TORC1 inhibitors, spermidine, senolytics, probiotics, and anti-inflammatories. Multiple clinical trials have commenced to evaluate the efficacy of such agents against age-associated diseases including diabetes, cardiovascular disease, cancer, and neurodegenerative diseases. There are reasonable expectations that drugs able to decelerate or reverse aging processes will also exert broad disease-preventing or -attenuating effects. Hence, the outcome of past, ongoing, and future disease-specific trials may pave the way to the development of new anti-aging medicines. Drugs approved for specific disease indications may subsequently be repurposed for the treatment of organism-wide aging consequences.PMID:38181790 | DOI:10.1016/j.cmet.2023.12.007

Cardioprotection by the adiponectin receptor agonist ALY688 in a preclinical mouse model of heart failure with reduced ejection fraction (HFrEF)

Fri, 05/01/2024 - 12:00
Biomed Pharmacother. 2024 Jan 3;171:116119. doi: 10.1016/j.biopha.2023.116119. Online ahead of print.ABSTRACTAIMS: Adiponectin has been shown to mediate cardioprotective effects and levels are typically reduced in patients with cardiometabolic disease. Hence, there has been intense interest in developing adiponectin-based therapeutics. The aim of this translational research study was to examine the functional significance of targeting adiponectin signaling with the adiponectin receptor agonist ALY688 in a mouse model of heart failure with reduced ejection fraction (HFrEF), and the mechanisms of cardiac remodeling leading to cardioprotection.METHODS AND RESULTS: Wild-type mice were subjected to transverse aortic constriction (TAC) to induce left ventricular pressure overload (PO), or sham surgery, with or without daily subcutaneous ALY688-SR administration. Temporal analysis of cardiac function was conducted via weekly echocardiography for 5 weeks and we observed that ALY688 attenuated the PO-induced dysfunction. ALY688 also reduced cardiac hypertrophic remodeling, assessed via LV mass, heart weight to body weight ratio, cardiomyocyte cross sectional area, ANP and BNP levels. ALY688 also attenuated PO-induced changes in myosin light and heavy chain expression. Collagen content and myofibroblast profile indicated that fibrosis was attenuated by ALY688 with TIMP1 and scleraxis/periostin identified as potential mechanistic contributors. ALY688 reduced PO-induced elevation in circulating cytokines including IL-5, IL-13 and IL-17, and the chemoattractants MCP-1, MIP-1β, MIP-1alpha and MIP-3α. Assessment of myocardial transcript levels indicated that ALY688 suppressed PO-induced elevations in IL-6, TLR-4 and IL-1β, collectively indicating anti-inflammatory effects. Targeted metabolomic profiling indicated that ALY688 increased fatty acid mobilization and oxidation, increased betaine and putrescine plus decreased sphingomyelin and lysophospholipids, a profile indicative of improved insulin sensitivity.CONCLUSION: These results indicate that the adiponectin mimetic peptide ALY688 reduced PO-induced fibrosis, hypertrophy, inflammation and metabolic dysfunction and represents a promising therapeutic approach for treating HFrEF in a clinical setting.PMID:38181714 | DOI:10.1016/j.biopha.2023.116119

Major lipids and lipoprotein levels and risk of blood pressure elevation: a Mendelian Randomisation study

Fri, 05/01/2024 - 12:00
EBioMedicine. 2024 Jan 4;100:104964. doi: 10.1016/j.ebiom.2023.104964. Online ahead of print.ABSTRACTBACKGROUND: Quantitative nuclear magnetic resonance (NMR) metabolomics techniques provide detailed measurements of lipoprotein particle concentration. Metabolic dysfunction often represents a cluster of conditions, including dyslipidaemia, hypertension, and diabetes, that increase the risk of cardiovascular diseases (CVDs). However, the causal relationship between lipid profiles and blood pressure (BP) remains unclear. We performed a Mendelian Randomisation (MR) study to disentangle and prioritize the potential causal effects of major lipids, lipoprotein particles, and circulating metabolites on BP and pulse pressure (PP).METHODS: We employed single-nucleotide polymorphisms (SNPs) associated with major lipids, lipoprotein particles, and other metabolites from the UK Biobank as instrumental variables. Summary-level data for BP and PP were obtained from the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort. Two-sample MR and MR Bayesian model averaging approaches (MR-BMA) were conducted to analyse and rank causal associations.FINDINGS: Genetically predicted TG was the most likely causal exposure among the major lipids to increase systolic blood pressure (SBP) and diastolic blood pressure (DBP), with marginal inclusion probabilities (MIPs) of 0.993 and 0.847, respectively. Among the majority of lipoproteins and their containing lipids, including major lipids, genetically elevated TG in small high-density lipoproteins (S_HDL_TG) had the strongest association with the increase of SBP and DBP, with MIPs of 0.416 and 0.397, respectively. HDL cholesterol (HDL_C) and low-density lipoprotein cholesterol (LDL_C) were potential causal factors for PP elevation among the major lipids (MIP = 0.927 for HDL_C and MIP = 0.718 for LDL_C). Within the sub-lipoproteins, genetically predicted atherogenic lipoprotein particles (i.e., sub-very low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), and LDL particles) had the most likely causal impact on increasing PP.INTERPRETATION: This study provides genetic evidence for the causality of lipids on BP indicators. However, the effect size on SBP, DBP, and PP varies depending on the lipids' components and sizes. Understanding this potential relationship may inform the potential benefits of comprehensive management of lipid profiles for BP control.FUNDING: Key Research and Development Program of Hubei Province, Science and Technology Innovation Project of Huanggang Central Hospital of Yangtze University, the Hubei Industrial Technology Research Institute of Heart-Brain Diseases, and the Hubei Provincial Engineering Research Centre of Comprehensive Care for Heart-Brain Diseases.PMID:38181703 | DOI:10.1016/j.ebiom.2023.104964

Densitometric method for assessment of six specialized metabolites in four Sida sp. and its congener Abutilon indicum: Targeted metabolomics, greenness assessment, and chemometrics analysis

Fri, 05/01/2024 - 12:00
J Pharm Biomed Anal. 2023 Dec 28;240:115945. doi: 10.1016/j.jpba.2023.115945. Online ahead of print.ABSTRACTSida is one of the most diverse genera, with about 200 species distributed in tropical and subtropical regions of the world. Among 18 species distributed in India, Sida acuta, Sida cordifolia, Sida rhombifolia, and Sida cordata are used in traditional medicines along with its possible adulterant Abutilon indicum for several therapeutic uses. The non-availability of marker-based validated methods for the identification and classification of these species leads to adulteration. Indoloquinoline and quinazoline are the major bioactive alkaloids distributed in Sida spp. First time, a simple, economical and high throughput method was developed and validated for the simultaneous determination of 20-hydroxyecdysone (1), vasicine (2), vasicinone (3), cryptolepine (4), quindolinone (5), and cryptolepinone (6) using HPTLC-UV densitometry. The method was validated to meet globally accepted ICH guidelines. The method was sensitive with LOD and LOQ ranging from 0.38-0.63 and 1.57-2.12 µg/band. The samples were spiked at 3 different concentrations, the recovery values were 93.49-98.88%. In addition, the greenness index of the HPTLC method was estimated using four different greenness assessment techniques. Targeted HPTLC analysis indicated the distribution of specialized metabolites in Sida spp. and A. indicum. However, the occurrence of cryptolepine in A. indicum was not reported in the literature, so this was further confirmed by liquid chromatographic studies of the samples from different locations. The chromatographic data was statistically evaluated by principal component analysis (PCA) and hierarchical clustering (HCA). HPTLC-based targeted metabolite quantitation explains the adulteration/substitution in Sida raw material and derived herbal preparations.PMID:38181556 | DOI:10.1016/j.jpba.2023.115945

Palmatine ameliorated lipopolysaccharide-induced sepsis-associated encephalopathy mice by regulating the microbiota-gut-brain axis

Fri, 05/01/2024 - 12:00
Phytomedicine. 2023 Dec 20;124:155307. doi: 10.1016/j.phymed.2023.155307. Online ahead of print.ABSTRACTBACKGROUND: Sepsis-associated encephalopathy (SAE), a common neurological complication from sepsis, is widespread among patients in intensive care unit and is linked to substantial morbidity and mortality rates, thus posing a substantial menace to human health. Due to the intricate nature of SAE's pathogenesis, there remains a dearth of efficacious therapeutic protocols, encompassing pharmaceutical agents and treatment modalities, up until the present time. Palmatine exhibits distinctive benefits in the regulation of inflammation for the improvement of sepsis. Nevertheless, the precise functions of palmatine in treating SAE and its underlying mechanism have yet to be elucidated.PURPOSE: This study aimed to evaluate efficiency of palmatine in SAE mice and its underlying mechanisms.STUDY DESIGN AND METHODS: Behavioral experiments, percent survival rate analysis, histological analysis, immunofluorescence staining, ELISA analysis, were performed to evaluate the efficiency of palmatine in SAE mice. Quantibody® mouse inflammation array glass chip was performed to observe the effects of palmatine on inflammation storm in SAE mice. Real-time quantitative and western blotting analyzes were employed to examine the expression of relevant targets in the Notch1/nuclear factor-kappa B (NF-κB) pathway. Finally, brain tissues metabolomics-based analyzes were performed to detect the differentially expressed metabolites and metabolic pathways. The fecal samples were subjected to microbial 16S rRNA analysis and untargeted metabolomics analysis in order to identify the specific flora and metabolites associated with SAE, thereby further investigating the mechanism of palmatine in SAE mice.RESULTS: Our results showed that palmatine significantly improved nerve function, reduced cell apoptosis in brain tissue, and decreased inflammatory cytokine levels in SAE induced-LPS mice. Meanwhile, our results demonstrate the potential of palmatine in modulating key components of the Notch1/NF-κB pathway, enhancing the expression of tight junction proteins, improving intestinal permeability, promoting the growth of beneficial bacteria (such as Lachnospiraceae_NK4A136_group), inhibiting the proliferation of harmful bacteria (such as Escherichia-Shigella), and mitigating metabolic disorders. Ultimately, these observed effects contribute to the therapeutic efficacy of palmatine in treating SAE.CONCLUSION: The findings of our study have provided confirmation regarding the efficacy of palmatine in the treatment of SAE, thereby establishing a solid foundation for further exploration into SAE therapy and the advancement and investigation of palmatine.PMID:38181529 | DOI:10.1016/j.phymed.2023.155307

Integrated microbiome and metabolomics revealed the protective effect of baicalin on alveolar bone inflammatory resorption in aging

Fri, 05/01/2024 - 12:00
Phytomedicine. 2023 Dec 7;124:155233. doi: 10.1016/j.phymed.2023.155233. Online ahead of print.ABSTRACTBACKGROUND: With the growing aging population and longer life expectancy, periodontitis and tooth loss have become major health concerns. The gut microbiota, as a key regulator in bone homeostasis, has gathered immense interest. Baicalin, a flavonoid compound extracted from Scutellaria baicalensis Georgi, has shown antioxidant and anti-inflammatory activities.PURPOSE: This study investigated, for the first time, the protective mechanism of baicalin against alveolar bone inflammatory resorption in aging mice by regulating intestinal flora and metabolites, as well as intestinal barrier function.METHODS: A ligature-induced periodontitis model was established in d-galactose (D-gal)-induced aging mice, and baicalin was administered at different dosages for 13 weeks. Body weight was measured weekly. The antioxidant and anti-inflammatory activity of baicalin were evaluated using serum superoxide dismutase (SOD), malonaldehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) levels. The immune capability was assessed by thymus and spleen indices. Histopathological changes were observed in the heart, liver, ileum, and periodontal tissues. Alveolar bone absorption of maxillary second molars was examined, and osteoclasts were counted by tartrate-resistant acid phosphatase (TRAP) staining. Furthermore, fecal samples were analyzed using 16S rRNA sequencing and non-targeted metabolomics to identify differences in intestinal bacterial composition and metabolites.RESULTS: Baicalin exhibited anti-aging properties, as evidenced by increased SOD activity and decreased levels of MDA, IL-6, and TNF-α in serum compared to the control group. Baicalin also ameliorated alveolar bone loss in the d-gal-induced aging-periodontitis group (p < 0.05). Furthermore, baicalin restored ileal permeability by up-regulating the expression of ZO-1 and occludin in aging-periodontitis groups (p < 0.05). Alpha diversity analysis indicated that baicalin-treated mice harbored a higher diversity of gut microbe. PCoA and ANOSIM results revealed significant dissimilarity between groups. The Firmicutes/Bacteroidetes (F/B) ratio, which decreased in periodontitis mice, was restored by baicalin treatment. Additionally, medium-dosage baicalin promoted the production of beneficial flavonoids, and enriched short-chain fatty acids (SCFAs)-producing bacteria.CONCLUSION: Intestinal homeostasis is a potential avenue for treating age-related alveolar bone loss. Baicalin exerts anti-inflammatory, antioxidant, and osteo-protective properties by regulating the gut microbiota and metabolites.PMID:38181526 | DOI:10.1016/j.phymed.2023.155233

Adaptive metabolic response to short-term intensive fasting

Fri, 05/01/2024 - 12:00
Clin Nutr. 2023 Dec 30;43(2):453-467. doi: 10.1016/j.clnu.2023.12.020. Online ahead of print.ABSTRACTBACKGROUND & AIMS: Short-term intensive fasting (STIF), known as beego in Chinese phonetic articulation, has been practiced for more than two thousand years. However, the potential risk of STIF and the body's response to the risk have not been adequately evaluated. This study aims to address this issue, focusing on the STIF-triggered metabolic response of the liver and kidney.METHODS: The STIF procedure in the clinical trial includes a 7-day water-only intensive fasting phase and a 7-day gradual refeeding phase followed by a regular diet. The intensive fasting in humans was assisted with psychological induction. To gain insights not available in the clinical trial, we designed a STIF program for mice that resulted in similar phenotypes seen in humans. Plasma metabolic profiling and examination of gene expression as well as liver and kidney function were performed by omics, molecular, biochemical and flow cytometric analyses. A human cell line model was also used for mechanistic study.RESULTS: Clinically significant metabolites of fat and protein were found to accumulate during the fasting phase, but they were relieved after gradual refeeding. Metabolomics profiling revealed a universal pattern in the consumption of metabolic intermediates, in which pyruvate and succinate are the two key metabolites during STIF. In the STIF mouse model, the accumulation of metabolites was mostly counteracted by the upregulation of catabolic enzymes in the liver, which was validated in a human cell model. Kidney filtration function was partially affected by STIF but could be recovered by refeeding. STIF also reduced oxidative and inflammatory levels in the liver and kidney. Moreover, STIF improved lipid metabolism in mice with fatty liver without causing accumulation of metabolites after STIF.CONCLUSIONS: The accumulation of metabolites induced by STIF can be relieved by spontaneous upregulation of catabolic enzymes, suggesting an adaptive and protective metabolic response to STIF stress in the mammalian body.PMID:38181523 | DOI:10.1016/j.clnu.2023.12.020

Regulation of RAS palmitoyltransferases by accessory proteins and palmitoylation

Fri, 05/01/2024 - 12:00
Nat Struct Mol Biol. 2024 Jan 5. doi: 10.1038/s41594-023-01183-5. Online ahead of print.ABSTRACTPalmitoylation of cysteine residues at the C-terminal hypervariable regions in human HRAS and NRAS, which is necessary for RAS signaling, is catalyzed by the acyltransferase DHHC9 in complex with its accessory protein GCP16. The molecular basis for the acyltransferase activity and the regulation of DHHC9 by GCP16 is not clear. Here we report the cryo-electron microscopy structures of the human DHHC9-GCP16 complex and its yeast counterpart-the Erf2-Erf4 complex, demonstrating that GCP16 and Erf4 are not directly involved in the catalytic process but stabilize the architecture of DHHC9 and Erf2, respectively. We found that a phospholipid binding to an arginine-rich region of DHHC9 and palmitoylation on three residues (C24, C25 and C288) were essential for the catalytic activity of the DHHC9-GCP16 complex. Moreover, we showed that GCP16 also formed complexes with DHHC14 and DHHC18 to catalyze RAS palmitoylation. These findings provide insights into the regulatory mechanism of RAS palmitoyltransferases.PMID:38182928 | DOI:10.1038/s41594-023-01183-5

TREM2 macrophage promotes cardiac repair in myocardial infarction by reprogramming metabolism via SLC25A53

Fri, 05/01/2024 - 12:00
Cell Death Differ. 2024 Jan 5. doi: 10.1038/s41418-023-01252-8. Online ahead of print.ABSTRACTEfferocytosis and metabolic reprogramming of macrophages play crucial roles in myocardial infarction (MI) repair. TREM2 has been proven to participate in phagocytosis and metabolism, but how it modulates myocardial infarction remains unclear. In this study, we showed that macrophage-specific TREM2 deficiency worsened cardiac function and impaired post-MI repair. Using RNA-seq, protein and molecular docking, and Targeted Metabolomics (LC-MS), our data demonstrated that macrophages expressing TREM2 exhibited decreased SLC25A53 transcription through the SYK-SMAD4 signaling pathway after efferocytosis, which impaired NAD+ transport into mitochondria, downregulated SLC25A53 thereby causing the breakpoint in the TCA cycle and subsequently increased itaconate production. In vitro experiments confirmed that itaconate secreted by TREM2+ macrophages inhibited cardiomyocyte apoptosis and promoted fibroblast proliferation. Conversely, overexpression of TREM2 in macrophages could improve cardiac function. In summary, our study reveals a novel role for macrophage-specific TREM2 in MI, connecting efferocytosis to immune metabolism during cardiac repair.PMID:38182899 | DOI:10.1038/s41418-023-01252-8

Screening and identification of unknown chemical contaminants in food based on liquid chromatography-high-resolution mass spectrometry and machine learning

Fri, 05/01/2024 - 12:00
Anal Chim Acta. 2024 Jan 25;1287:342116. doi: 10.1016/j.aca.2023.342116. Epub 2023 Dec 8.ABSTRACTUnknown or unexpected chemical contaminants and/or their transformation products in food that may be harmful to humans need to be discovered for comprehensive safety evaluation. Liquid chromatography-high-resolution mass spectrometry (LC-HRMS) is a powerful tool for detecting chemical contaminants in food samples. However, identifying all of peaks in LC-HRMS is not possible, but if class information is known in advance, further identification will become easier. In this work, a novel MS2 spectra classification-driven screening strategy was constructed based on LC-HRMS and machine learning. First, the classification model was developed based on machine learning algorithm using class information and experimental MS2 data of chemical contaminants and other non-contaminants. By using the developed artificial neural network classification model, in total 32 classes of pesticides, veterinary drugs and mycotoxins were classified with good prediction accuracy and low false-positive rate. Based on the classification model, a screening procedure was developed in which the classes of unknown features in LC-HRMS were first predicted through the classification model, and then their structures were identified under the guidance of class information. Finally, the developed strategy was tentatively applied to the analysis of pork and aquatic products, and 8 chemical contaminants and 11 transformation products belonging to 8 classes were found. This strategy enables screening of unknown chemical contaminants and transformation products in complex food matrices.PMID:38182389 | DOI:10.1016/j.aca.2023.342116

Protective role of fetal bovine serum on PLHC-1 spheroids exposed to a mixture of plastic additives: A lipidomic perspective

Fri, 05/01/2024 - 12:00
Toxicol In Vitro. 2024 Jan 3:105771. doi: 10.1016/j.tiv.2024.105771. Online ahead of print.ABSTRACTThe use of fetal bovine serum (FBS) in cell culture is being questioned for scientific and ethical reasons, prompting the exploration of alternative approaches. Nevertheless, the influence of FBS on cell functioning, especially in fish cells, has not been comprehensively examined. This study aims to evaluate the impact of FBS on the lipidome of PLHC-1 spheroids and investigate cellular and molecular responses to plastic additives in the presence/absence of FBS. Lipidomic analyses were conducted on PLHC-1 cell spheroids using liquid chromatography coupled with a high-resolution quadrupole time-of-flight mass spectrometer (HRMS-QToF). The removal of FBS from the culture medium for 24 h significantly changed the lipid profile of spheroids, resulting in a depletion of cholesterol esters (CEs), phosphatidylcholines (PCs) and lyso-phosphatidylcholines (LPCs), while ceramides and certain glycerophospholipids slightly increased. Additionally, the exclusion of FBS from the medium led to increased cytotoxicity caused by a mixture of plastic additives and increased lipidomic alterations, including an elevation of ceramides. This study emphasizes the protective role of serum components in fish liver spheroids against a mixture of plastic additives and underscores the importance of considering exposure conditions when studying metabolomic and lipidomic responses to toxicants.PMID:38182034 | DOI:10.1016/j.tiv.2024.105771

The transmembrane protein TMEM182 promotes fat deposition and alters metabolomics and lipidomics

Fri, 05/01/2024 - 12:00
Int J Biol Macromol. 2024 Jan 3:129144. doi: 10.1016/j.ijbiomac.2023.129144. Online ahead of print.ABSTRACTTMEM182, a transmembrane protein highly expressed in muscle and adipose tissues, plays a crucial role in muscle cell differentiation, metabolism, and signaling. However, its role in fat deposition and metabolism is still unknown. In this study, we used overexpression and knockout models to examine the impact of TMEM182 on fat synthesis and metabolism. Our results showed that TMEM182 overexpression increased the expression of fat synthesis-related genes and promoted the differentiation of preadipocytes into fat cells. In TMEM182 knockout mice, there was a significant decrease in abdominal fat deposition. RNA sequencing results showed that TMEM182 overexpression in preadipocytes enhanced the activity of pathways related to fat formation, ECM-receptor interaction, and cell adhesion. Furthermore, our analysis using UPLC-MS/MS showed that TMEM182 significantly altered the metabolite and lipid content and composition in chicken breast muscle. Specifically, TMEM182 increased the content of amino acids and their derivatives in chicken breast muscle, promoting amino acid metabolic pathways. Lipidomics also revealed a significant increase in the content of glycerophospholipids, sphingolipids, and phospholipids in the breast muscle after TMEM182 overexpression. These findings suggest that TMEM182 plays a crucial role in regulating fat deposition and metabolism, making it a potential target for treating obesity-related diseases and animal breeding.PMID:38181918 | DOI:10.1016/j.ijbiomac.2023.129144

Ileitis promotes MASLD progression via bile acid modulation and enhanced TGR5 signaling in ileal CD8+ T cells

Fri, 05/01/2024 - 12:00
J Hepatol. 2024 Jan 3:S0168-8278(24)00004-7. doi: 10.1016/j.jhep.2023.12.024. Online ahead of print.ABSTRACTBACKGROUND: Clinical evidence substantiates a link between inflammatory bowel disease (IBD), particularly Crohn's disease (CD), and metabolic dysfunction associated steatotic liver disease (MASLD). This study aims to explore the underlying molecular mechanisms responsible for this association.METHODS: MASLD was induced by administering high-fat and western diets, while IBD was induced using dextran sulfate sodium salt (DSS) and the Il10 KO mice model. The investigation into the role of secondary bile acids (SBA) in ileitis involved employing metagenomic sequencing, conducting metabolomics detection, performing fecal bacterial transplantation, and constructing CD8+ T cell specific gene knockout mice.RESULTS: In MASLD+DSS and Il10 KO MASLD mice, we observed ileitis characterized by T cell infiltration and activation in the terminal ileum. This condition resulted in decreased bile acid levels in the portal vein and liver, inhibited hepatic Farnesol X receptor (FXR) activation, and exacerbated MASLD. Metagenomic and metabolomic analysis of ileum contents revealed increased Clostridium proliferation and elevated SBA levels in MASLD-associated ileitis. Experiments using germ-free mice and fecal microbiota transplantation suggested an association between SBA and MASLD-related ileitis. In vitro, SBA promoted CD8+ T cell activation via the TGR5, mTOR, and Oxidative Phosphorylation (OXPHOS) pathways. In vivo, TGR5 knockout in CD8+ T cells effectively alleviated ileitis and worsened the MASLD phenotype. Clinical data further supported these findings, demonstrating a positive correlation ileitis and MASLD.CONCLUSION: MASLD-induced changes in intestinal flora result in elevated levels of SBA in the ileum. In the presence of compromised intestinal barrier, this leads to severe CD8+ T cell-mediated ileitis through the TGR5/mTOR/OXPHOS signaling pathway. Ileitis-induced tissue damage impairs enterohepatic circulation, inhibits hepatic FXR activation, and exacerbates the MASLD phenotype.IMPACT AND IMPLICATIONS: Our study provides a comprehensive investigation of the interplay and underlying mechanisms connecting ileitis and MASLD. SBA produced by intestinal bacteria, as the critical link between MASLD and ileitis. This compound exerts its influence by disrupting liver lipid metabolism through the promotion of CD8+ T cell-mediated ileitis. In future endeavors to prevent and treat MASLD, it is essential to thoroughly account for the impact of the intestinal tract, especially the ileum, on liver function via the enterohepatic circulation.PMID:38181823 | DOI:10.1016/j.jhep.2023.12.024

Molecular profiling of sponge deflation reveals an ancient relaxant-inflammatory response

Fri, 05/01/2024 - 12:00
Curr Biol. 2023 Dec 28:S0960-9822(23)01676-7. doi: 10.1016/j.cub.2023.12.021. Online ahead of print.ABSTRACTA hallmark of animals is the coordination of whole-body movement. Neurons and muscles are central to this, yet coordinated movements also exist in sponges that lack these cell types. Sponges are sessile animals with a complex canal system for filter-feeding. They undergo whole-body movements resembling "contractions" that lead to canal closure and water expulsion. Here, we combine live 3D optical coherence microscopy, pharmacology, and functional proteomics to elucidate the sequence and detail of shape changes, the tissues and molecular physiology involved, and the control of these movements. Morphometric analysis and targeted perturbation suggest that the movement is driven by the relaxation of actomyosin stress fibers in epithelial canal cells, which leads to whole-body deflation via collapse of the incurrent and expansion of the excurrent canal system. Thermal proteome profiling and quantitative phosphoproteomics confirm the control of cellular relaxation by an Akt/NO/PKG/PKA pathway. Agitation-induced deflation leads to differential phosphorylation of proteins forming epithelial cell junctions, implying their mechanosensitive role. Unexpectedly, untargeted metabolomics detect a concomitant decrease in antioxidant molecules during deflation, reflecting an increase in reactive oxygen species. Together with the secretion of proteinases, cytokines, and granulin, this indicates an inflammation-like state of the deflating sponge reminiscent of vascular endothelial cells experiencing oscillatory shear stress. These results suggest the conservation of an ancient relaxant-inflammatory response of perturbed fluid-carrying systems in animals and offer a possible mechanism for whole-body coordination through diffusible paracrine signals and mechanotransduction.PMID:38181793 | DOI:10.1016/j.cub.2023.12.021

Metabolomic assessment of African snail (Achatina fulica) meal on growth performance of giant river prawn (Macrobrachium rosenbergii)

Fri, 05/01/2024 - 12:00
Comp Biochem Physiol Part D Genomics Proteomics. 2023 Dec 29;49:101185. doi: 10.1016/j.cbd.2023.101185. Online ahead of print.ABSTRACTThis study aimed to investigate the effects of replacing fishmeal (FM) with African giant snail (Achatina fulica) meal (SM) on the growth performance of giant river prawn (Macrobrachium rosenbergii), as well as to analyze the associated metabolomic changes. Six diets were formulated, replacing FM with SM at different inclusion levels ranging from 0 % to 100 %. Growth performance and feed conversion ratio of prawns fed diets with FM replaced by SM up to 80 % were not significantly different from control. In contrast, significantly decreased growth performance and higher feed conversion ratio (FCR) occurred with diets containing 100 % SM. To gain insights into the metabolic regulation of prawns fed different diets, a 1H NMR metabolomics approach was used to assess the metabolic changes in prawns fed diets containing 0 % and 80 % SM. The results revealed up-regulated metabolites significantly involved in several metabolic pathways, including alanine, aspartate, and glutamate metabolism; citrate cycle (TCA cycle); aminoacyl-tRNA biosynthesis; and valine, leucine, and isoleucine biosynthesis. These findings imply that including SM in the diet might modulate the regulation of muscle amino acids and tRNA synthesis, suggesting a potential impact on protein biosynthesis mechanisms. Additionally, alterations in the TCA cycle may reflect changes in carbon utilization, potentially contributing to the growth performance of giant river prawns when fishmeal is replaced with SM without adversely affecting their growth. In conclusion, this study demonstrated that SM could be a promising alternative protein source in aquafeed. The metabolomic approach provides valuable insights into the metabolic changes in prawns fed different diets, aiding in the development of more effective aquafeeds in the future. The study's limitations, such as the simplified diet formulation and the limited scope of the metabolomic analysis, were acknowledged and discussed, highlighting the need for further research to build upon these findings.PMID:38181663 | DOI:10.1016/j.cbd.2023.101185

Pages