The acetylation of MDH1 and IDH1 is associated with energy metabolism in acute liver failure

The liver is the main organ associated with metabolism. In our previous studies, we identified that the metabolic enzymes malate dehydrogenase 1 (MDH1) and isocitrate dehydrogenase 1 (IDH1) were differentially expressed in ALF. The aim of this study was to explore the changes in the acetylation of MDH1 and IDH1 and the therapeutic effect of histone deacetylase (HDAC) inhibitor in acute liver failure (ALF). Decreased levels of many metabolites were observed in ALF patients. MDH1 and IDH1 were decreased in the livers of ALF patients. The HDAC inhibitor ACY1215 improved the expression of MDH1 and IDH1 after treatment with MDH1-siRNA and IDH1-siRNA. Transfection with mutant plasmids and adeno-associated viruses, identified MDH1 K118 acetylation and IDH1 K93 acetylation as two important sites that regulate metabolism in vitro and in vivo.

Quantifying the effect of nutritional interventions on metabolic resilience using personalized computational models

The manifestation of metabolic deteriorations that accompany overweight and obesity can differ greatly between individuals, giving rise to a highly heterogeneous population. This inter-individual variation can impede both the provision and assessment of nutritional interventions as multiple aspects of metabolic health should be considered at once. Here, we apply the Mixed Meal Model, a physiology-based computational model, to characterize an individual's metabolic health in silico. A population of 342 personalized models were generated using data for individuals with overweight and obesity from three independent intervention studies, demonstrating a strong relationship between the model-derived metric of insulin resistance (ρ = 0.67, p < 0.05) and the gold-standard hyperinsulinemic-euglycemic clamp. The model is also shown to quantify liver fat accumulation and β-cell functionality. Moreover, we show that personalized Mixed Meal Models can be used to evaluate the impact of a dietary intervention on multiple aspects of metabolic health at the individual level.

Oleic acid triggers metabolic rewiring of T cells poising them for T helper 9 differentiation

T cells are the most common immune cells in atherosclerotic plaques, and the function of T cells can be altered by fatty acids. Here, we show that pre-exposure of CD4+ T cells to oleic acid, an abundant fatty acid linked to cardiovascular events, upregulates core metabolic pathways and promotes differentiation into interleukin-9 (IL-9)-producing cells upon activation. RNA sequencing of non-activated T cells reveals that oleic acid upregulates genes encoding key enzymes responsible for cholesterol and fatty acid biosynthesis. Transcription footprint analysis links these expression changes to the differentiation toward TH9 cells, a pro-atherogenic subset. Spectral flow cytometry shows that pre-exposure to oleic acid results in a skew toward IL-9+-producing T cells upon activation. Importantly, pharmacological inhibition of either cholesterol or fatty acid biosynthesis abolishes this effect, suggesting a beneficial role for statins beyond cholesterol lowering. Taken together, oleic acid may affect inflammatory diseases like atherosclerosis by rewiring T cell metabolism.

Exploring the role of epicardial adipose-tissue-derived extracellular vesicles in cardiovascular diseases

Epicardial adipose tissue (EAT) is a fat depot located between the myocardium and the visceral layer of the epicardium, which, owing to its location, can influence surrounding tissues and can act as a local transducer of systemic inflammation. The mechanisms upon which such influence depends on are however unclear. Given the role EAT undoubtedly has in the scheme of cardiovascular diseases (CVDs), understanding the impact of its cellular components is of upmost importance. Extracellular vesicles (EVs) constitute promising candidates to fill the gap in the knowledge concerning the unexplored mechanisms through which EAT promotes onset and progression of CVDs. Owing to their ability of transporting active biomolecules, EAT-derived EVs have been reported to be actively involved in the pathogenesis of ischemia/reperfusion injury, coronary atherosclerosis, heart failure, and atrial fibrillation. Exploring the precise functions EVs exert in this context may aid in connecting the dots between EAT and CVDs.

Integrated modeling of labile and glycated hemoglobin with glucose for enhanced diabetes detection and short-term monitoring

Metabolic biomarkers, particularly glycated hemoglobin and fasting plasma glucose, are pivotal in the diagnosis and control of diabetes mellitus. Despite their importance, they exhibit limitations in assessing short-term glucose variations. In this study, we propose labile hemoglobin as an additional biomarker, providing insightful perspectives into these fluctuations. By utilizing datasets from 40,652 retrospective general participants and conducting glucose tolerance tests on 60 prospective pediatric subjects, we explored the relationship between plasma glucose and labile hemoglobin. A mathematical model was developed to encapsulate short-term glucose kinetics in the pediatric group. Applying dimensionality reduction techniques, we successfully identified participant subclusters, facilitating the differentiation between diabetic and non-diabetic individuals. Intriguingly, by integrating labile hemoglobin measurements with plasma glucose values, we were able to predict the likelihood of diabetes in pediatric subjects, underscoring the potential of labile hemoglobin as a significant glycemic biomarker for diabetes research.

Intraintestinal fermentation of fructo- and galacto-oligosaccharides and the fate of short-chain fatty acids in humans

Consumption of fructo- (FOS) and galacto-oligosaccharides (GOS) has health benefits which have been linked in part to short-chain fatty acids (SCFA) production by the gut microbiota. However, detailed knowledge of this process in the human intestine is lacking. We aimed to determine the acute fermentation kinetics of a FOS:GOS mixture in healthy males using a naso-intestinal catheter for sampling directly in the ileum or colon. We studied the fate of SCFA as substrates for glucose and lipid metabolism by the host after infusion of 13C-SCFA. In the human distal ileum, no fermentation of FOS:GOS, nor SCFA production, or bacterial cross-feeding was observed. The relative composition of intestinal microbiota changed rapidly during the test day, which demonstrates the relevance of postprandial intestinal sampling to track acute responses of the microbial community toward interventions. SCFA were vividly taken up and metabolized by the host as shown by incorporation of 13C in various host metabolites.

Metabolic rewiring and autophagy inhibition correct lysosomal storage disease in mucopolysaccharidosis IIIB

Mucopolysaccharidoses (MPSs) are lysosomal disorders with neurological involvement for which no cure exists. Here, we show that recombinant NK1 fragment of hepatocyte growth factor rescues substrate accumulation and lysosomal defects in MPS I, IIIA and IIIB patient fibroblasts. We investigated PI3K/Akt pathway, which is of crucial importance for neuronal function and survival, and demonstrate that PI3K inhibition abolishes NK1 therapeutic effects. We identified that autophagy inhibition, by Beclin1 silencing, reduces MPS IIIB phenotype and that NK1 downregulates autophagic-lysosome (ALP) gene expression, suggesting a possible contribution of autophagosome biogenesis in MPS. Indeed, metabolomic analyses revealed defects of mitochondrial activity accompanied by anaerobic metabolism and inhibition of AMP-activated protein kinase (AMPK), which acts on metabolism and autophagy, rescues lysosomal defects. These results provide insights into the molecular mechanisms of MPS IIIB physiopathology, supporting the development of new promising approaches based on autophagy inhibition and metabolic rewiring to correct lysosomal pathology in MPSs.

Fat infiltration in skeletal muscle: Influential triggers and regulatory mechanism

Fat infiltration in skeletal muscle (also known as myosteatosis) is now recognized as a distinct disease from sarcopenia and is directly related to declining muscle capacity. Hence, understanding the origins and regulatory mechanisms of fat infiltration is vital for maintaining skeletal muscle development and improving human health. In this article, we summarized the triggering factors such as aging, metabolic diseases and metabolic syndromes, nonmetabolic diseases, and muscle injury that all induce fat infiltration in skeletal muscle. We discussed recent advances on the cellular origins of fat infiltration and found several cell types including myogenic cells and non-myogenic cells that contribute to myosteatosis. Furthermore, we reviewed the molecular regulatory mechanism, detection methods, and intervention strategies of fat infiltration in skeletal muscle. Based on the current findings, our review will provide new insight into regulating function and lipid metabolism of skeletal muscle and treating muscle-related diseases.

Prevalence and impact of diabetes in patients with valvular heart disease

This study aimed to investigate the prevalence of diabetes in valvular heart disease (VHD), as well as the relationship of diabetes with severity of valvular lesions and clinical outcome. A total of 11,862 patients with significant (≥moderate) VHD from the China Valvular Heart Disease study were included in the analysis. The primary outcome was the composite of all-cause death, hospitalization for heart failure, and myocardial infarction during two-year follow-up. The prevalence of diabetes was 14.5% (1,721/11,862) in VHD. After adjusting for patients' demographics, diabetes was associated with a significantly lower risk of severe valvular lesion in aortic regurgitation and mitral regurgitation (MR). In multivariable analysis, diabetes was identified as an independent predictor of two-year outcome in patients with MR (hazard ratio: 1.345, 95% confidence interval: 1.069-1.692, p = 0.011). More efforts should be made to enhance our understanding and improve outcomes of concomitant VHD and diabetes.

Calcium oscillations optimize the energetic efficiency of mitochondrial metabolism

Energy transduction is central to living organisms, but the impact of enzyme regulation and signaling on its thermodynamic efficiency is generally overlooked. Here, we analyze the efficiency of ATP production by the tricarboxylic acid cycle and oxidative phosphorylation, which generate most of the chemical energy in eukaryotes. Calcium signaling regulates this pathway and can affect its energetic output, but the concrete energetic impact of this cross-talk remains elusive. Calcium enhances ATP production by activating key enzymes of the tricarboxylic acid cycle while calcium homeostasis is ATP-dependent. We propose a detailed kinetic model describing the calcium-mitochondria cross-talk and analyze it using nonequilibrium thermodynamics: after identifying the effective reactions driving mitochondrial metabolism out of equilibrium, we quantify the mitochondrial thermodynamic efficiency for different conditions. Calcium oscillations, triggered by extracellular stimulation or energy deficiency, boost the thermodynamic efficiency of mitochondrial metabolism, suggesting a compensatory role of calcium signaling in mitochondrial bioenergetics.

Time-restricted eating improves health because of energy deficit and circadian rhythm: A systematic review and meta-analysis

Time-restricted eating (TRE) is an effective way to lose weight and improve metabolic health in animals. Yet whether and how these benefits apply to humans is unclear. This systematic review and meta-analysis examined the effect of TRE in people with overweight and obesity statuses. The results showed that TRE led to modest weight loss, lower waist circumference and energy deficits. TRE also improved body mass index, fat mass, lean body mass, systolic blood pressure, fasting glucose levels, fasting insulin levels, and HbA1c%. Subgroup analysis demonstrated more health improvements in the TRE group than the control group under the ad libitum intake condition than in the energy-prescribed condition. Eating time-of-day advantages were only seen when there was considerable energy reduction in the TRE group than the control group (ad libitum condition), implying that the benefits of TRE were primarily due to energy deficit, followed by alignment with eating time of day.

Collinsella aerofaciens linked with increased ethanol production and liver inflammation contribute to the pathophysiology of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is an emerging global health problem and a potential risk factor for metabolic diseases. The bidirectional interactions between liver and gut made dysbiotic gut microbiome one of the key risk factors for NAFLD. In this study, we reported an increased abundance of Collinsella aerofaciens in the gut of obese and NASH patients living in India. We isolated C. aerofaciens from the fecal samples of biopsy-proven NASH patients and observed that their genome is enriched with carbohydrate metabolism, fatty acid biosynthesis, and pro-inflammatory functions and have the potency to increase ethanol level in blood. An animal study indicated that mice supplemented with C. aerofaciens had increased levels of circulatory ethanol, high levels of hepatic hydroxyproline, triglyceride, and inflammation in the liver. The present findings indicate that perturbation in the gut microbiome composition is a key risk factor for NAFLD.

Identification of commensal gut bacterial strains with lipogenic effects contributing to NAFLD in children

Gut microbiota is known to have a significant impact on nonalcoholic fatty liver disease (NAFLD), particularly in children with obesity. However, the specific functions of microbiota at the strain level in this population have not been fully elucidated. In this study, we successfully isolated and identified several commensal gut bacterial strains that were dominant in children with obesity and NAFLD. Among these, four novel isolates were found to have significant lipogenic effects in vitro. These strains exhibited a potential link to hepatocyte steatosis by regulating the expression of genes involved in lipid metabolism and inflammation. Moreover, a larger cohort analysis confirmed that these identified bacterial strains were enriched in the NAFLD group. The integrated analysis of these strains effectively distinguished NASH from NAFL. These four strains might serve as potential biomarkers in children with NAFLD. These findings provided new insights into the exploration of therapeutic targets for NAFLD.

High glucose impairs cognitive function through inducing mitochondrial calcium overload in Treg cells

High glucose has been proved to impair cognitive function in type 2 diabetes, but the underlying mechanisms remain elusive. Here, we found that high glucose increased transcription factors' SP1 O-GlcNAcylation in regulatory T (Treg) cells. Glycosylated SP1 further enhanced HDAC2 recruitment and histone deacetylation on Na+/Ca2+/Li+ exchanger (NCLX) promoter, which downregulated NCLX expression and led to mitochondrial calcium overload and oxidative damage, thereby promoting Treg cell dysfunction, M1 microglia polarization, and diabetes-associated cognitive impairment. Importantly, GLP-1 receptor agonist alleviated these deleterious effects via GLP-1-receptor-mediated upregulation of OGA and inhibition of SP1 O-GlcNAcylation in Treg cells. Our study highlighted a link between high-glucose-mediated SP1 O-GlcNAcylation and HDAC2/NCLX signaling in control of mitochondrial calcium concentrations in Treg cells. It also revealed a mechanism for linking Treg cell dysfunction and cognitive impairment in type 2 diabetes and provides an insight into the mechanism underlying the neuroprotective effects of GLP-1 receptor agonist.

Employing broad learning and non-invasive risk factor to improve the early diagnosis of metabolic syndrome

Metabolic syndrome (MetS) as a multifactorial disease is highly prevalent in countries and individuals. Monitoring the conventional risk factors (CRFs) would be a cost-effective strategy to target the increasing prevalence of MetS and the potential of noninvasive CRF for precisely detection of MetS in the early stage remains to be explored. From large-scale multicenter MetS clinical dataset, we discover 15 non-invasive CRFs which have strong relevance with MetS and first propose a broad learning-based approach named Genetic Programming Collaborative-competitive Broad Learning System (GP-CCBLS) with noninvasive CRF for early detection of MetS. The proposed GP-CCBLS model can significantly boost the detection performance and achieve the accuracy of 80.54%. This study supports the potential clinical validity of noninvasive CRF to complement general diagnostic criteria for early detecting the MetS and also illustrates possible strength of broad learning in disease diagnosis comparing with other machine learning approaches.

Adipocyte hypertrophy associates with in vivo postprandial fatty acid metabolism and adipose single-cell transcriptional dynamics

Adipocyte hypertrophy is associated with metabolic complications independent of obesity. We aimed to determine: 1) the association between adipocyte size and postprandial fatty acid metabolism; 2) the potential mechanisms driving the obesity-independent, hypertrophy-associated dysmetabolism in vivo and at a single-cell resolution. Tracers with positron emission tomography were used to measure fatty acid metabolism in 40 men and women with normal or impaired glucose tolerance (NCT02808182), and single nuclei RNA-sequencing (snRNA-seq) to determine transcriptional dynamics of subcutaneous adipose tissue (AT) between individuals with AT hypertrophy vs. hyperplasia matched for sex, ethnicity, glucose-tolerance status, BMI, total and percent body fat, and waist circumference. Adipocyte size was associated with high postprandial total cardiac fatty acid uptake and higher visceral AT dietary fatty acid uptake, but lower lean tissue dietary fatty acid uptake. We found major shifts in cell transcriptomal dynamics with AT hypertrophy that were consistent with in vivo metabolic changes.

Renin-angiotensin system inhibitor discontinuation in COVID-19 did not modify systemic ACE2 in a randomized controlled trial

Despite the similar clinical outcomes after renin-angiotensin system (RAS) inhibitor (RASi) continuation or withdrawal in COVID-19, the effects on angiotensin-converting enzyme 2 (ACE2) and RAS metabolites remain unclear. In a substudy of the randomized controlled Austrian Corona Virus Adaptive Clinical Trial (ACOVACT), patients with hypertension and COVID-19 were randomized 1:1 to either RASi continuation (n = 30) or switch to a non-RASi medication (n = 29). RAS metabolites were analyzed using a mixed linear regression model (n = 30). Time to a sustained clinical improvement was equal and ACE2 did not differ between the groups but increased over time in both. Overall ACE2 was higher with severe COVID-19. ACE-S and Ang II levels increased as expected with ACE inhibitor discontinuation. These data support the safety of RASi continuation in COVID-19, although RASi were frequently discontinued in our post hoc analysis. The study was not powered to draw definite conclusions on clinical outcomes using small sample sizes.

Exosomes derived from platelet-rich plasma promote diabetic wound healing via the JAK2/STAT3 pathway

Diabetic non-healing wounds are bringing a heavy burden on patients and society. Platelet-rich plasma (PRP) has been widely applied in tissue regenerating for containing various growth factors. Recently, PRP-derived exosomes (PRP-Exos) have been proved to be more effective than PRP in tissue regeneration. However, few studies have investigated the therapeutic potential of PRP-Exos in diabetic wound healing to date. Therefore, we extracted and identified exosomes derived from PRP and tested its promoting effect on diabetic wound healing in vivo and in vitro. We found that high glucose (HG) inhibited cell proliferation and migration and induced apoptosis through ROS-dependent activation of the JNK and p38 MAPK signaling pathways. PRP-Exos can stimulate fibroblast functions and accelerate diabetic wound healing. The benefits of PRP-Exos may be attributed to its capability to prevent HG-induced ROS-dependent apoptosis via the PDGF-BB/JAK2/STAT3/Bcl-2 signaling pathway. This illustrates the therapeutic potential of PRP-Exos in diabetic wounds.

A data-driven computational model for obesity-driven diabetes onset and remission through weight loss

Obesity is a major risk factor for the development of type 2 diabetes (T2D), where a sustained weight loss may result in T2D remission in individuals with obesity. To design effective and feasible intervention strategies to prevent or reverse T2D, it is imperative to study the progression of T2D and remission together. Unfortunately, this is not possible through experimental and observational studies. To address this issue, we introduce a data-driven computational model and use human data to investigate the progression of T2D with obesity and remission through weight loss on the same timeline. We identify thresholds for the emergence of T2D and necessary conditions for remission. We explain why remission is only possible within a window of opportunity and the way that window depends on the progression history of T2D, individual's metabolic state, and calorie restrictions. These findings can help to optimize therapeutic intervention strategies for T2D prevention or treatment.

Metabolic predictors of response to immune checkpoint blockade therapy

Metabolism of immune cells in the tumor microenvironment (TME) plays a critical role in cancer patient response to immune checkpoint inhibitors (ICI). Yet, a metabolic characterization of immune cells in the TME of patients treated with ICI is lacking. To bridge this gap we performed a semi-supervised analysis of ∼1700 metabolic genes using single-cell RNA-seq data of > 1 million immune cells from ∼230 samples of cancer patients treated with ICI. When clustering cells based on their metabolic gene expression, we found that similar immunological cellular states are found in different metabolic states. Most importantly, we found metabolic states that are significantly associated with patient response. We then built a metabolic predictor based on a dozen gene signature, which significantly differentiates between responding and non-responding patients across different cancer types (AUC = 0.8-0.92). Taken together, our results demonstrate the power of metabolism in predicting patient response to ICI.

Effects of hepatic mitochondrial pyruvate carrier deficiency on de novo lipogenesis and gluconeogenesis in mice

The liver coordinates the systemic response to nutrient deprivation and availability by producing glucose from gluconeogenesis during fasting and synthesizing lipids via de novo lipogenesis (DNL) when carbohydrates are abundant. Mitochondrial pyruvate metabolism is thought to play important roles in both gluconeogenesis and DNL. We examined the effects of hepatocyte-specific mitochondrial pyruvate carrier (MPC) deletion on the fasting-refeeding response. Rates of DNL during refeeding were impaired by hepatocyte MPC deletion, but this did not reduce intrahepatic lipid content. During fasting, glycerol is converted to glucose by two pathways; a direct cytosolic pathway and an indirect mitochondrial pathway requiring the MPC. Hepatocyte MPC deletion reduced the incorporation of 13C-glycerol into TCA cycle metabolites, but not into new glucose. Furthermore, suppression of glycerol and alanine metabolism did not affect glucose concentrations in fasted hepatocyte-specific MPC-deficient mice, suggesting multiple layers of redundancy in glycemic control in mice.

Personalized glucose-lowering effect of chiglitazar in type 2 diabetes

Chiglitazar (carfloglitazar) is a peroxisome proliferator-activated receptor pan-agonist presenting non-inferior glucose-lowering efficacy with sitagliptin in patients with type 2 diabetes. To delineate the subgroup of patients with greater benefit from chiglitazar, we conducted a machine learning-based post-hoc analysis in two randomized controlled trials. We established a character phenomap based on 13 variables and estimated HbA1c decline to the effects of chiglitazar in reference to sitagliptin. Out of 1,069 patients, 63.3% were found to have greater reduction in HbA1c levels with chiglitazar, while 36.7% showed greater reduction with sitagliptin. This distinction in treatment response was statistically significant between groups (pinteraction<0.001). To identify patients who would gain the most glycemic control benefit from chiglitazar, we developed a machine learning model, ML-PANPPAR, which demonstrated robust performance using sex, BMI, HbA1c, HDL, and fasting insulin. The phenomapping-derived tool successfully identified chiglitazar responders and enabled personalized drug allocation in patients with drug-naïve diabetes.

Intestinal microbial circadian rhythms drive sex differences in host immunity and metabolism

Circadian rhythms dynamically regulate sex differences in metabolism and immunity, and circadian disruption increases the risk of metabolic disorders. We investigated the role of sex-specific intestinal microbial circadian rhythms in host metabolism using germ-free and conventionalized mice and manipulation of dietary-derived fat, fiber, and microbiota-accessible carbohydrates. Our findings demonstrate that sex differences in circadian rhythms of genes involved in immunity and metabolism depend on oscillations in microbiota, microbial metabolic functions, and microbial metabolites. Further, we show that consuming an obesogenic, high-fat, low-fiber diet produced sex-specific changes in circadian rhythms in microbiota, metabolites, and host gene expression, which were linked to sex differences in the severity of metabolic dysfunction. Our results reveal that microbial circadian rhythms contribute to sex differences in immunity and metabolism and that dietary factors can entrain new circadian rhythms and modify the magnitude of sex differences in host-microbe circadian dynamics.

Mitochondrial dysfunction, lipids metabolism, and amino acid biosynthesis are key pathways for COVID-19 recovery

The metabolic alterations caused by SARS-CoV-2 infection reflect disease progression. To analyze molecules involved in these metabolic changes, a multiomics study was performed using plasma from 103 patients with different degrees of COVID-19 severity during the evolution of the infection. With the increased severity of COVID-19, changes in circulating proteomic, metabolomic, and lipidomic profiles increased. Notably, the group of severe and critical patients with high HRG and ChoE (20:3) and low alpha-ketoglutaric acid levels had a high chance of unfavorable disease evolution (AUC = 0.925). Consequently, patients with the worst prognosis presented alterations in the TCA cycle (mitochondrial dysfunction), lipid metabolism, amino acid biosynthesis, and coagulation. Our findings increase knowledge regarding how SARS-CoV-2 infection affects different metabolic pathways and help in understanding the future consequences of COVID-19 to identify potential therapeutic targets.

Thyroid hormone treatment counteracts cellular phenotypical remodeling in diabetic organs

Diabetes mellitus and alterations in thyroid hormone (TH) signaling are closely linked. Though the role of TH signaling in cell differentiation and growth is well known, it remains unclear whether its alterations contribute to the pathobiology of diabetic cells. Here, we aim to investigate whether the administration of exogenous T3 can counteract the cellular remodeling that occurs in diabetic cardiomyocytes, podocytes, and pancreatic beta cells. Treating diabetic rats with T3 prevents dedifferentiation, pathological growth, and ultrastructural alterations in podocytes and cardiomyocytes. In vitro, T3 reverses glucose-induced growth in human podocytes and cardiomyocytes, restores cardiomyocyte cytoarchitecture, and reverses pathological alterations in kidney and cardiac organoids. Finally, T3 treatment counteracts glucose-induced transdifferentiation, cell growth, and loss in pancreatic beta cells through TH receptor alpha1 activation. Our studies indicate that TH signaling activation substantially counteracts diabetes-induced pathological remodeling, and provide a potential therapeutic approach for the treatment of diabetes and its complications.

Promoting metabolic inefficiency for metabolic disease

Recent advances in pharmacotherapies that promote appetite suppression have shown remarkable weight loss. Therapies targeting energy expenditure lag behind, and as such none have yet been identified to be safe and efficacious for sustaining negative energy balance toward weight loss. Multiple energy dissipating pathways have been identified in adipose tissue and muscle. The molecular effectors of some of these pathways have been identified, but much is still left to be learned about their regulation. Understanding the molecular underpinnings of metabolic inefficiency in adipose tissue and muscle is required if these pathways are to be therapeutically targeted in the context of obesity and obesity-accelerated diseases.

Phosphorylated YBX2 is stabilized to promote glycolysis in brown adipocytes

Y-box binding protein 2 (YBX2) is an essential modulator of brown adipose tissue activation, yet the regulation on its own expression and the involved mechanism remains largely unknown. Herein, we report the YBX2 protein level, but not mRNA level, is induced in response to acute β-adrenergic signaling. In this context, YBX2 is a dual substrate for both AMPK and Akt2. The phosphorylation at Thr115 by AMPK or at Ser137 by Akt2 facilitates YBX2 accumulation in brown adipocytes by decreasing ubiquitination-mediated degradation. Beyond stabilizing PGC1α mRNA, increased YBX2 upon thermogenic activation assists the expression of glycolytic enzymes, promotes glucose utilization and lactate production. Mechanistically, YBX2 modulates translation of glycolytic genes via direct binding to 5'-UTRs of these genes. Together these findings suggest YBX2 is responsive to thermogenic stimuli by phosphorylation modification, and stabilized YBX2 helps to boost glycolysis and thermogenesis in brown adipocytes.

High-fat diet impact on intestinal cholesterol conversion by the microbiota and serum cholesterol levels

Cholesterol-to-coprostanol conversion by the intestinal microbiota has been suggested to reduce intestinal and serum cholesterol availability, but the relationship between intestinal cholesterol conversion and the gut microbiota, dietary habits, and serum lipids has not been characterized in detail. We measured conserved proportions of cholesterol high and low-converter types in individuals with and without obesity from two distinct, independent low-carbohydrate high-fat (LCHF) dietary intervention studies. Across both cohorts, cholesterol conversion increased in previous low-converters after LCHF diet and was positively correlated with the fecal relative abundance of Eubacterium coprostanoligenes. Lean cholesterol high-converters had increased serum triacylglycerides and decreased HDL-C levels before LCHF diet and responded to the intervention with increased LDL-C, independently of fat, cholesterol, and saturated fatty acid intake. Our findings identify the cholesterol high-converter type as a microbiome marker, which in metabolically healthy lean individuals is associated with increased LDL-C in response to LCHF.

Human metabolism and excretion kinetics of the surfactant 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) after oral and dermal administration

2,4,7,9-Tetramethyl-5-decyne-4,7-diol (TMDD) is a non-ionic surfactant with a wide range of applications. TMDD is considered a high-production chemical and, due to its low biodegradation rate, possesses a potentially high prevalence in the environment. However, despite its widespread use, toxicokinetic data and data on internal exposure to TMDD in the general population are completely lacking. Hence, we developed a human biomonitoring (HBM) method for TMDD. Our approach included a metabolism study with four subjects, who were administered an oral dose of 75 µg TMDD/kg body weight and a dermal dose of 750 µg/kg body weight. Terminal methyl-hydroxylated TMDD (1-OH-TMDD) was previously identified as the main urinary metabolite in our lab. The results of the oral and dermal applications were used to determine the toxicokinetic parameters of 1-OH-TMDD as a biomarker of exposure. Finally, the method was applied to 50 urine samples from non-occupationally exposed volunteers. Results show that TMDD was rapidly metabolized, with an average tmax of 1.7 h and a rapid and almost complete (96%) excretion of 1-OH-TMDD until 12 h after oral dosage. Elimination was bi-phasic, with half-lives of 0.75-1.6 h and 3.4-3.6 h for phases 1 and 2, respectively. The dermal application resulted in a delayed urinary excretion of this metabolite with a tmax of 12 h and complete excretion after about 48 h. The excreted amounts of 1-OH-TMDD represented 18% of the orally administered TMDD dose. The data of the metabolism study demonstrated a fast oral as well as substantial dermal resorption of TMDD. Moreover, the results indicated an effective metabolism of 1-OH-TMDD, which is excreted rapidly and completely via urine. Application of the method to 50 urine samples revealed a quantification rate of 90%, with an average concentration of 0.19 ng/mL (0.97 nmol/g creatinine). With the urinary excretion factor (Fue) derived from the metabolism study, we estimated an average daily intake of 1.65 µg TMDD from environmental and dietary sources. In conclusion, 1-OH-TMDD in urine is a suitable biomarker of exposure to TMDD and can be applied for biomonitoring of the general population.

Type 2 diabetes susceptibility gene GRK5 regulates physiological pancreatic β-cell proliferation via phosphorylation of HDAC5

Restoring functional β cell mass is a potential therapy for those with diabetes. However, the pathways regulating β cell mass are not fully understood. Previously, we demonstrated that Sox4 is required for β cell proliferation during prediabetes. Here, we report that Sox4 regulates β cell mass through modulating expression of the type 2 diabetes (T2D) susceptibility gene GRK5. β cell-specific Grk5 knockout mice showed impaired glucose tolerance with reduced β cell mass, which was accompanied by upregulation of cell cycle inhibitor gene Cdkn1a. Furthermore, we found that Grk5 may drive β cell proliferation through a pathway that includes phosphorylation of HDAC5 and subsequent transcription of immediate-early genes (IEGs) such as Nr4a1, Fosb, Junb, Arc, Egr1, and Srf. Together, these studies suggest GRK5 is linked to T2D through regulation of β cell growth and that it may be a target to preserve β cells during the development of T2D.

Autophagy ablation in skeletal muscles worsens sepsis-induced muscle wasting, impairs whole-body metabolism, and decreases survival

Septic patients frequently develop skeletal muscle wasting and weakness, resulting in severe clinical consequences and adverse outcomes. Sepsis triggers sustained induction of autophagy, a key cellular degradative pathway, in skeletal muscles. However, the impact of enhanced autophagy on sepsis-induced muscle dysfunction remains unclear. Using an inducible and muscle-specific Atg7 knockout mouse model (Atg7iSkM-KO), we investigated the functional importance of skeletal muscle autophagy in sepsis using the cecal ligation and puncture model. Atg7iSkM-KO mice exhibited a more severe phenotype in response to sepsis, marked by severe muscle wasting, hypoglycemia, higher ketone levels, and a decreased in survival as compared to mice with intact Atg7. Sepsis and Atg7 deletion resulted in the accumulation of mitochondrial dysfunction, although sepsis did not further worsen mitochondrial dysfunction in Atg7iSkM-KO mice. Overall, our study demonstrates that autophagy inactivation in skeletal muscles triggers significant worsening of sepsis-induced muscle and metabolic dysfunctions and negatively impacts survival.

SGLT1/2 inhibition improves glycemic control and multi-organ protection in type 1 diabetes

Sodium glucose cotransporters (SGLTs) are transport proteins that are expressed throughout the body. Inhibition of SGLTs is a relatively novel therapeutic strategy to improve glycemic control and has been shown to promote cardiorenal benefits. Dual SGLT1/2 inhibitors (SGLT1/2i) such as sotagliflozin target both SGLT1 and 2 proteins. Sotagliflozin or vehicle was administered to diabetic Akimba mice for 8 weeks at a dose of 25 mg/kg/day. Urine glucose levels, water consumption, and body weight were measured weekly. Serum, kidney, pancreas, and brain tissue were harvested under terminal anesthesia. Tissues were assessed using immunohistochemistry or ELISA techniques. Treatment with sotagliflozin promoted multiple metabolic benefits in diabetic Akimba mice resulting in decreased blood glucose and improved polydipsia. Sotagliflozin also prevented mortalities associated with diabetes. Our data suggests that there is the possibility that combined SGLT1/2i may be superior to SGLT2i in controlling glucose homeostasis and provides protection of multiple organs affected by diabetes.

Protein supplementation changes gut microbial diversity and derived metabolites in subjects with type 2 diabetes

High-protein diets are promoted for individuals with type 2 diabetes (T2D). However, effects of dietary protein interventions on (gut-derived) metabolites in T2D remains understudied. We therefore performed a multi-center, randomized-controlled, isocaloric protein intervention with 151 participants following either 12-week high-protein (HP; 30Energy %, N = 78) vs. low-protein (LP; 10 Energy%, N = 73) diet. Primary objectives were dietary effects on glycemic control which were determined via glycemic excursions, continuous glucose monitors and HbA1c. Secondary objectives were impact of diet on gut microbiota composition and -derived metabolites which were determined by shotgun-metagenomics and mass spectrometry. Analyses were performed using delta changes adjusting for center, baseline, and kidney function when appropriate. This study found that a short-term 12-week isocaloric protein modulation does not affect glycemic parameters or weight in metformin-treated T2D. However, the HP diet slightly worsened kidney function, increased alpha-diversity, and production of potentially harmful microbiota-dependent metabolites, which may affect host metabolism upon prolonged exposure.

Different exercise training intensities prevent type 2 diabetes mellitus-induced myocardial injury in male mice

Type 2 diabetes mellitus (T2DM) usually develop myocardial injury and that exercise may have a positive effect on cardiac function. However, the effect of exercise intensity on cardiac function has not yet been fully examined. This study aimed to explore different exercise intensities on T2DM-induced myocardial injury. 18-week-old male mice were randomly divided into four groups: a control group, the T2DM, T2DM + medium-intensity continuous training (T2DM + MICT), and T2DM + high-intensity interval training (T2DM + HIIT) groups. In the experimental group, mice were given high-fat foods and streptozotocin for six weeks and then divided into two exercise training groups, in which mice were subjected to exercise five days per week for 24 consecutive weeks. Finally, metabolic characteristics, cardiac function, myocardial remodeling, myocardial fibrosis, oxidative stress, and apoptosis were analyzed. HIIT treatment improved cardiac function and improved myocardial injury. In conclusion, HIIT may be an effective means to guard against T2DM-induced myocardial injury.

Correlation between gut microbiota and the development of Graves' disease: A prospective study

The association between gut microbiota and development of Graves' disease (GD) remains unclear. This study aimed to profile the gut microbiota of 65 patients newly diagnosed with GD before and after treatment and 33 physical examination personnel via 16S rRNA sequencing. Significant differences in the gut microbiota composition were observed between the two groups, showing relative bacterial abundances of 1 class, 1 order, 5 families, and 14 genera. After treatment, the abundance of the significantly enriched biota in the GD group decreased considerably, whereas that of the previously decreased biota increased considerably. Further, interleukin-17 levels decreased significantly. The random forest method was used to identify 12 genera that can distinguish patients with GD from healthy controls. Our study revealed that the gut microbiota of patients with GD exhibit unique characteristics compared with that of healthy individuals, which may be related to an imbalance in the immune system and gut microbiota.

Large-scale metabolomic profiling and incident non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent disease with no specific drug therapy. High-throughput metabolomics present an unprecedented opportunity to identify biomarkers and potentially causal risk factors for NAFLD. Here, we determined the impact of 21 circulating metabolites, 17 lipids, and 132 lipoprotein particle characteristics on NAFLD combining prospective observational and two-sample Mendelian randomization (MR) analyses in 121,032 UK Biobank participants. We identified several metabolic factors associated with NAFLD risk in observational and MR analyses including triglyceride-rich and high-density lipoprotein particles composition, as well as the ratio of polyunsaturated fatty acids to total fatty acids. This study, is one of the largest to investigate incident NAFLD, provides concordant observational and genetic evidence that therapies aimed at reducing circulating triglycerides and increasing large HDL particles, as well as interventions aimed at increasing polyunsaturated fatty acid content may warrant further investigation into NAFLD prevention and treatment.

Moderate-intensity endurance training improves late phase β-cell function in adults with type 2 diabetes

Physical activity is important for type 2 diabetes treatment, yet the underlying mechanisms for these beneficial effects of exercise are not fully understood. Here, we investigated the effects of exercise training on biphasic β-cell insulin secretory function, a key factor regulating blood glucose. Adults with type 2 diabetes (7F/3M, age 49 ± 5 years, BMI 30 ± 3 kg/m²) completed a 10-week moderate-intensity exercise program and multiple components of glucose homeostasis were measured. Training improved glycemic control, insulin sensitivity, and processing of proinsulin-to-insulin. Training increased late phase β-cell function by 38% (p = 0.01), which was correlated with changes in VO_2peak suggesting training response-dependent effects. Ras-Responsive Element Binding Protein 1 (RREB1) concentrations, a protein postulated to increase type 2 diabetes risk, were inversely correlated with increases in training-induced late-phase disposition index, consistent with an inhibitory role of RREB1 on insulin secretion. Moderate-intensity exercise training improves late-phase β-cell function and glycemic control in adults with type 2 diabetes.

What the BTBR/J mouse has taught us about diabetes and diabetic complications

Human and mouse genetics have delivered numerous diabetogenic loci, but it is mainly through the use of animal models that the pathophysiological basis for their contribution to diabetes has been investigated. More than 20 years ago, we serendipidously identified a mouse strain that could serve as a model of obesity-prone type 2 diabetes, the BTBR (Black and Tan Brachyury) mouse (BTBR T+ Itpr3tf/J, 2018) carrying the Lepob mutation. We went on to discover that the BTBR-Lepob mouse is an excellent model of diabetic nephropathy and is now widely used by nephrologists in academia and the pharmaceutical industry. In this review, we describe the motivation for developing this animal model, the many genes identified and the insights about diabetes and diabetes complications derived from >100 studies conducted in this remarkable animal model.

Plant sterols and cholesterol metabolism are associated with five-year cognitive decline in the elderly population

Dysregulations in cholesterol metabolism are associated with neurodegenerative and vascular pathologies, and dementia. Diet-derived plant sterols (phytosterols) have cholesterol-lowering, anti-inflammatory, and antioxidant properties and may interfere with neurodegeneration and cognitive decline. Here we performed multivariate analysis in 720 individuals enrolled in a population-based prospective study to determine whether circulating cholesterol precursors and metabolites, triglycerides, and phytosterols, are associated with cognitive impairment and decline in the older population. We report specific dysregulations of endogenous cholesterol synthesis and metabolism, and diet-derived phytosterols, and their changes over time associated with cognitive impairment, and decline in the general population. These findings suggest circulating sterols levels could be considered in risk evaluation and are relevant for the development of strategies to prevent cognitive decline in older people.

A consortium of three-bacteria isolated from human feces inhibits formation of atherosclerotic deposits and lowers lipid levels in a mouse model

By a survey of metagenome-wide association studies (MWAS), we found a robust depletion of Bacteroides cellulosilyticus, Faecalibacterium prausnitzii, and Roseburia intestinalis in individuals with atherosclerotic cardiovascular disease (ACVD). From an established collection of bacteria isolated from healthy Chinese individuals, we selected B. cellulosilyticus, R. intestinalis, and Faecalibacterium longum, a bacterium related to F. prausnitzii, and tested the effects of these bacteria in an Apoe^/- atherosclerosis mouse model. We show that administration of these three bacterial species to Apoe^-/- mice robustly improves cardiac function, reduces plasma lipid levels, and attenuates the formation of atherosclerotic plaques. Comprehensive analysis of gut microbiota, plasma metabolome, and liver transcriptome revealed that the beneficial effects are associated with a modulation of the gut microbiota linked to a 7α-dehydroxylation-lithocholic acid (LCA)-farnesoid X receptor (FXR) pathway. Our study provides insights into transcriptional and metabolic impact whereby specific bacteria may hold promises for prevention/treatment of ACVD.

N-arachidonylglycine is a caloric state-dependent circulating metabolite which regulates human CD4+T cell responsiveness

Caloric deprivation interventions such as intermittent fasting and caloric restriction ameliorate metabolic and inflammatory disease. As a human model of caloric deprivation, a 24-h fast blunts innate and adaptive immune cell responsiveness relative to the refed state. Isolated serum at these time points confers these same immunomodulatory effects on transformed cell lines. To identify serum mediators orchestrating this, metabolomic and lipidomic analysis was performed on serum extracted after a 24-h fast and re-feeding. Bioinformatic integration with concurrent peripheral blood mononuclear cells RNA-seq analysis implicated key metabolite-sensing GPCRs in fasting-mediated immunomodulation. The putative GPR18 ligand N-arachidonylglycine (NAGly) was elevated during fasting and attenuated CD4⁺T cell responsiveness via GPR18 MTORC1 signaling. In parallel, NAGly reduced inflammatory Th1 and Th17 cytokines levels in CD4⁺T cells isolated from obese subjects, identifying a fasting-responsive metabolic intermediate that may contribute to the regulation of nutrient-level dependent inflammation associated with metabolic disease.

Steroidogenic factor 1 protects mice from obesity-induced glucose intolerance via improving glucose-stimulated insulin secretion by beta cells

As a potential druggable nuclear receptor, steroidogenic factor 1 (SF1) regulates obesity and insulin resistance in the ventromedial hypothalamic nucleus. Herein, we sought to demonstrate its expression and functions in islets in the development of obesity-induced diabetes. SF1 was barely detected in the beta cells of lean mice but highly expressed in those of non-diabetic obese mice, while decreased in diabetic ones. Conditional deletion of SF1 in beta cells predisposed diet-induced obese (DIO) mice to glucose intolerance by perturbing glucose-stimulated insulin secretion (GSIS). Consistently, forced expression of SF1 restored favorable glucose homeostasis in DIO and db/db mice by improving GSIS. In isolated islets and MIN6, overexpression of SF1 also potentiated GSIS, mediated by improvement of mitochondrial ATP production. The underlying mechanisms may involve oxidative phosphorylation and lipid metabolism. Collectively, SF1 in beta cell preserves GSIS to promote beta-cell adaptation to obesity and hence is a potential therapeutic target for obesity-induced diabetes.

Cord serum metabolic signatures of future progression to immune-mediated diseases

Previous prospective studies suggest that progression to autoimmune diseases is preceded by metabolic dysregulation, but it is not clear which metabolic changes are disease-specific and which are common across multiple immune-mediated diseases. Here we investigated metabolic profiles in cord serum in a general population cohort (All Babies In Southeast Sweden; ABIS), comprising infants who progressed to one or more immune-mediated diseases later in life: type 1 diabetes (n = 12), celiac disease (n = 28), juvenile idiopathic arthritis (n = 9), inflammatory bowel disease (n = 7), and hypothyroidism (n = 6); and matched controls (n = 270). We observed elevated levels of multiple triacylglycerols (TGs) an alteration in several gut microbiota related metabolites in the autoimmune groups. The most distinct differences were observed in those infants who later developed HT. The specific similarities observed in metabolic profiles across autoimmune diseases suggest that they share specific common metabolic phenotypes at birth that contrast with those of healthy controls.

Association between cumulative lipoprotein(a) exposure and adverse cardiovascular outcomes in patients with prediabetes or diabetes

Few studies have characterized long-term exposure to lipoprotein(a), or Lp(a), different glucose metabolism status, and their joint role in adverse cardiovascular outcomes risk. We consecutively enrolled 10,724 coronary heart disease (CAD) patients from January to December 2013 in Fuwai Hospital. Associations of cumulative lipoprotein(a) (CumLp(a)) exposure and different glucose metabolism status with major adverse cardiac and cerebrovascular events (MACCEs) risk were evaluated using Cox regression models. Compared with participants with normal glucose regulation and lower CumLp(a), those with type 2 diabetes and higher CumLp(a) were at the highest risk (HR 1.56, 95% CI 1.25-1.94), and those with prediabetes and higher CumLp(a) and those with type 2 diabetes and lower CumLp(a) were at relatively higher risk (HR 1.41, 95% CI 1.14-1.76; HR 1.37, 95% CI 1.11-1.69; respectively). Similar findings concerning the joint association were observed in sensitivity analyses. Cumulative lipoprotein(a) exposure and different glucose metabolism status were associated with 5-year MACCEs risk and may be useful concurrently for guiding secondary prevention therapy decisions.

Successful naltrexone-bupropion treatment after several treatment failures in a patient with severe monogenic obesity

We describe the therapeutic journey of a 33-year-old patient with early-onset obesity (BMI 56.7 kg/m²) and hyperphagia due to a likely pathogenic heterozygous melanocortin-4 receptor (MC4R) gene variant. She was unsuccessfully treated with several intensive lifestyle interventions, gastric bypass surgery (-40 kg weight loss, followed by +39.8 kg weight regain), liraglutide 3 mg (-3.8% weight loss with sustained hyperphagia), and metformin treatment. However, naltrexone-bupropion treatment led to -48.9 kg (-26.7%) weight loss, of which -39.9 kg (-38.3%) was fat mass, in 17 months of treatment. Importantly, she reported improved hyperphagia and quality of life. We describe the potential beneficial effects of naltrexone-bupropion on weight, hyperphagia, and quality of life in a patient with genetic obesity. This extensive journey shows that various anti-obesity agents can be initiated, subsequently terminated when ineffective and substituted with other anti-obesity agents to identify the most efficient anti-obesity treatment.

E-DES-PROT: A novel computational model to describe the effects of amino acids and protein on postprandial glucose and insulin dynamics in humans

Current computational models of whole-body glucose homeostasis describe physiological processes by which insulin regulates circulating glucose concentrations. While these models perform well in response to oral glucose challenges, interaction with other nutrients that impact postprandial glucose metabolism, such as amino acids (AAs), is not considered. Here, we developed a computational model of the human glucose-insulin system, which incorporates the effects of AAs on insulin secretion and hepatic glucose production. This model was applied to postprandial glucose and insulin time-series data following different AA challenges (with and without co-ingestion of glucose), dried milk protein ingredients, and dairy products. Our findings demonstrate that this model allows accurate description of postprandial glucose and insulin dynamics and provides insight into the physiological processes underlying meal responses. This model may facilitate the development of computational models that describe glucose homeostasis following the intake of multiple macronutrients, while capturing relevant features of an individual's metabolic health.

Obesity control by SHIP inhibition requires pan-paralog inhibition and an intact eosinophil compartment

Here we extend the understanding of how chemical inhibition of SHIP paralogs controls obesity. We compare different classes of SHIP inhibitors and find that selective inhibitors of SHIP1 or SHIP2 are unable to prevent weight gain and body fat accumulation during increased caloric intake. Surprisingly, only pan-SHIP1/2 inhibitors (pan-SHIPi) prevent diet-induced obesity. We confirm that pan-SHIPi is essential by showing that dual treatment with SHIP1 and SHIP2 selective inhibitors reduced adiposity during excess caloric intake. Consistent with this, genetic inactivation of both SHIP paralogs in eosinophils or myeloid cells also reduces obesity and adiposity. In fact, pan-SHIPi requires an eosinophil compartment to prevent diet-induced adiposity, demonstrating that pan-SHIPi acts via an immune mechanism. We also find that pan-SHIPi increases ILC2 cell function in aged, obese mice to reduce their obesity. Finally, we show that pan-SHIPi also reduces hyperglycemia, but not via eosinophils, indicating a separate mechanism for glucose control.

Metabolic activity grows in human cancers pushed by phenotypic variability

Different evolutionary processes push cancers to increasingly aggressive behaviors, energetically sustained by metabolic reprogramming. The collective signature emerging from this transition is macroscopically displayed by positron emission tomography (PET). In fact, the most readily PET measure, the maximum standardized uptake value (SUV_max), has been found to have prognostic value in different cancers. However, few works have linked the properties of this metabolic hotspot to cancer evolutionary dynamics. Here, by analyzing diagnostic PET images from 512 patients with cancer, we found that SUV_max scales superlinearly with the mean metabolic activity (SUV_mean), reflecting a dynamic preferential accumulation of activity on the hotspot. Additionally, SUV_max increased with metabolic tumor volume (MTV) following a power law. The behavior from the patients data was accurately captured by a mechanistic evolutionary dynamics model of tumor growth accounting for phenotypic transitions. This suggests that non-genetic changes may suffice to fuel the observed sustained increases in tumor metabolic activity.

PIMT regulates hepatic gluconeogenesis in mice

The physiological and metabolic functions of PIMT/TGS1, a third-generation transcriptional apparatus protein, in glucose homeostasis sustenance are unclear. Here, we observed that the expression of PIMT was upregulated in the livers of short-term fasted and obese mice. Lentiviruses expressing Tgs1-specific shRNA or cDNA were injected into wild-type mice. Gene expression, hepatic glucose output, glucose tolerance, and insulin sensitivity were evaluated in mice and primary hepatocytes. Genetic modulation of PIMT exerted a direct positive impact on the gluconeogenic gene expression program and hepatic glucose output. Molecular studies utilizing cultured cells, in vivo models, genetic manipulation, and PKA pharmacological inhibition establish that PKA regulates PIMT at post-transcriptional/translational and post-translational levels. PKA enhanced 3'UTR-mediated translation of TGS1 mRNA and phosphorylated PIMT at Ser656, increasing Ep300-mediated gluconeogenic transcriptional activity. The PKA-PIMT-Ep300 signaling module and associated PIMT regulation may serve as a key driver of gluconeogenesis, positioning PIMT as a critical hepatic glucose sensor.

Apolipoprotein H induces sex-specific steatohepatitis and gut dysbiosis during chronic hepatitis B infection

Apolipoprotein H (APOH) is involved in lipid metabolism and functions as an acute-phase protein during hepatitis B virus (HBV) infection. Herein, we explored whether APOH acts on the development of fatty liver upon chronic HBV infection. Serum APOH level was significantly lower in cirrhosis patients than in healthy controls or patients with chronic infection. It showed sex bias, with elevated levels in female patients with chronic infection. Also, serum APOH levels were negatively correlated with HBV surface antigen (HBsAg) but positively correlated with albumin and triglyceride levels. In In vitro HBV infection model, HBV upregulated APOH expression in a non-temporal manner, and HBsAg levels were elevated by silencing APOH. RNA sequencing (RNA-seq) demonstrated bidirectional expression of APOH, which impacted the immunoregulation upon infection or the metabolic regulation in HepG2.2.15 cells. Then, ApoH ^-/- mice with persistent HBV replication displayed steatohepatitis and gut microbiota dysbiosis with synergistic sex differences. Our study deciphers the roles of APOH in chronic liver diseases.