Regulation of hepatic glucose metabolism in health and disease

Clostridium butyricum ameliorates post-gastrectomy insulin resistance by regulating the mTORC1 signaling pathway through the gut-liver axis

Postoperative insulin resistance (IR) is a metabolic disorder characterized by decreased insulin sensitivity and elevated blood glucose levels following major surgery. Our previous clinical study identified a notable correlation between postoperative IR and gut microbiota, particularly butyrate-producing bacteria, yet the mechanisms remain unclear. In this study, we established gastric resection SD rat models to evaluate the impact of Clostridium butyricum NCU-27 (butyrate-producing bacteria) on postoperative IR. The results demonstrated significant reductions in fasting blood glucose (FBG), fasting insulin (FIns) levels, and HOMA-IR (6.64 ± 0.76 vs. 11.47 ± 1.32; 4.27 ± 0.59 vs. 7.40 ± 0.54) in the postoperative period compared to the control group (P < 0.05). Additionally, glucose tolerance and hepatic glycogen content were markedly improved (P < 0.001). Further exploration of butyrate demonstrated effects similar to C. butyricum NCU-27, potentially mediated through the gut-liver axis by inhibiting mTORC1 expression in liver cells, activating the IRS1/AKT pathway, enhancing glucose uptake and glycogen synthesis, suppressing gluconeogenesis, increasing insulin sensitivity, and improving IR. Finally, the use of mTORC1 agonists and inhibitors further confirmed the critical role of the mTORC1 pathway in mediating the beneficial effects of C. butyricum NCU-27 and butyrate on postoperative IR. In conclusion, this study elucidated that C. butyricum NCU-27 improves postoperative IR by regulating butyrate metabolism and inhibiting the mTORC1 pathway, offering new insights for preventing and treating post-gastrectomy IR.

Current understanding of insulin dysregulation and its relationship with carbohydrate and protein metabolism in horses

Insulin dysregulation (ID) is a common metabolic disorder in horses, characterized by hyperinsulinemia and/or peripheral insulin resistance. The critical role of hyperinsulinemia in endocrinopathic laminitis has driven research into the insulinotropic effects of dietary nutrients and the reciprocal impact of ID on nutrient metabolism. The relationship between ID and carbohydrate metabolism has been extensively studied; however, the effects of ID on protein metabolism in horses remain largely unexplored. This review begins with an overview of the importance of insulin in the regulation of muscle protein synthesis and degradation and then examines the current understanding of the interplay between ID and protein and carbohydrate metabolism in horses. Horses with ID exhibit altered resting plasma amino acid concentrations and shifts in postprandial amino acid dynamics. Recent work illustrated that ID horses had higher levels of plasma amino acids following a protein meal and delayed postprandial clearance from the blood compared to non-ID horses. The postprandial muscle synthetic response does not seem to be diminished in ID horses, but alterations in key cellular signaling molecules have been reported. ID horses display a pronounced hyperinsulinemic response following the consumption of feeds providing a range of protein, non-structural carbohydrate, starch and water-soluble carbohydrate intakes. Recent studies have shown that ID horses have an increased postprandial incretin response, contributing to the observed hyperinsulinemia. To minimize the postprandial insulin response, thresholds for carbohydrate consumption have recently been proposed. Similar thresholds should be established for protein to aid in the refinement of nutritional strategies to manage ID horses.

Arctiin attenuated NASH by inhibiting glycolysis and inflammation via FGFR2/CSF1R signaling

The present work was conducted to evaluate the pharmacological effect of Arctiin(ARC) on high fat diet(HFD)-induced Non-alcoholic steatohepatitis(NASH) and investigate its potential mechanism. The network pharmacology and bioinformatic analyses predicted that FGFR2 might be the potential target of ARC. Palmitic acid(PA)-induced AML12 cell was employed as the in vitro model. ARC reduced the levels of ALT, AST, TC, TG, and attenuated histopathological alteration. ARC inhibited inflammatory cytokines, inflammatory molecules, downregulated the expressions of FGFR2/CSF1R, inhibited glycolysis and promoted oxidative phosphorylation both in vivo and in vitro. ARC enhanced mitochondrial membrane potential and reduced oxidative stress. The application of FGFR2-OE plasmid, CSF1R-OE plasmid, CSF1R inhibitor PLX indicated that ARC attenuated glycolysis and inflammation in PA-induced AML12 cells via FGFR2/CSF1R signaling. HIF1A was proved to be involved in this process using HIF1A agonist DEF and HIF1A inhibitor PX478. Molecular docking and molecular dynamic suggested that ARC might combine with FGFR2. In conclusion, the present study demonstrated that ARC ameliorated NASH by inhibiting glycolysis and inflammation via FGFR2/CSF1R signaling.

Vitamin D3 ameliorates hyperglycemia by modulating gut microbiota and metabolites in prediabetic KKay mice

Prediabetes represents a pivotal stage in the development and pathogenesis of diabetes, during which notable alterations in the gut microbiota can be observed. Vitamin D (VD) showed anti-diabetic properties, but it is unknown whether the improvement of VD on hyperglycemia is associated with gut microbiota. Thus, our objective was to investigate and verify the effects of VD3 on glucose metabolism in prediabetes, as well as to elucidate the underlying mechanisms. In this study, different concentrations of VD3 were intraperitoneally administered to prediabetic mice induced by high fat diet for 16 weeks. Biochemical analyses, oral glucose tolerance test, 16S rRNA and untargeted metabolomics were used, the mechanism was explored. Then, fecal suspensions collected from the above donors were transplanted into KKay mice for 6 weeks, and the relevant indicators were measured. The results showed that VD3 intervention alleviated glucose metabolism in KKay mice. It increased the protein expression of colon tight junction proteins, alleviated metabolic endotoxemia and inflammation, so that reduced tumor necrosis factor alpha (TNFα) induced toll-like receptor 4/nuclear factor kappa-B (TLR4/NFκB) and improvement of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) insulin signaling pathway. VD3 affected the structure of gut microbiota and metabolites, and functional prediction analysis suggested that VD3 may affect carbohydrate. Besides, the effect of VD3 could be delivered by fecal microbiota transplantation (FMT). Consequently, VD3 ameliorate glucose metabolism by modulating gut microbiota and metabolites in KKay mice, and this ability could be transferred by FMT.

LYPLAL1 enzyme activity is linked to hepatic glucose metabolism

The serine hydrolase LYPLAL1 is a poorly characterised enzyme with emerging roles in hepatic metabolism. A multitude of association studies have shown links between variants of this gene locus and metabolic conditions such as obesity and insulin resistance. However, the enzyme's function is still largely unknown. Recent biochemical studies have revealed that it may play a role in hepatic glucose metabolism and that its activity is allosterically regulated. Herein, we use a selective activity-based probe to delineate LYPLAL1's involvement in hepatic metabolism. We show that the enzyme's activity is modulated during metabolic stress, specifically pointing to a putative role in negatively regulating gluconeogenesis and upregulating glycolysis. We also determine that knock-out of the enzyme does not affect liver lipid profiles and bring forth evidence for insulin-mediated control of LYPLAL1 in HepG2 cells. Furthermore, LYPLAL1 activity appears to be largely post-translationally regulated as gene expression levels remain largely constant under insulin and glucagon treatments. Taken together these data point to an enzymatic role in regulating glucose metabolism that may be part of a feedback mechanism of signal transduction.

Endocrine regulation of metabolic crosstalk between liver and brown adipose tissue by natural active ingredients

The escalating global obesity crisis and its associated metabolic disorders have posed a significant threat to public health, increasing the risk of major health issues such as cardiovascular diseases and type 2 diabetes. Central to metabolic regulation are the liver and brown adipose tissue (BAT), which orchestrate glycolipid metabolism, thermogenesis, and energy homeostasis. Emerging evidence highlights the role of natural bioactive compounds-such as polyphenols (e.g., resveratrol, curcumin), alkaloids (e.g., berberine), and terpenoids (e.g., paeoniflorin, shikonin)-in modulating liver-BAT crosstalk. These compounds influence critical pathways, including AMPK activation, PPAR signaling, and UCP1-mediated thermogenesis, to enhance lipid oxidation, suppress gluconeogenesis, and improve insulin sensitivity. This review systematically examines how these natural agents regulate metabolic interplay between the liver and BAT, addressing their effects on energy expenditure, carbohydrate utilization, and lipid mobilization. Key mechanisms involve the suppression of hepatic lipogenesis, promotion of BAT-mediated thermogenesis, and secretion of hepatokines (e.g., FGF21) and batokines that coordinate interorgan communication. By synthesizing preclinical and clinical findings, we highlight the translational potential of dietary interventions and nutraceuticals targeting liver-BAT axis dysfunction. Future research should prioritize mechanistic studies, dose optimization, and personalized approaches to harness these compounds for combating obesity-related diseases. These insights underscore the promise of natural bioactive molecules as adjuvants to lifestyle modifications, offering innovative strategies for metabolic health restoration.

Effects of high-intensity interval training on metabolic impairments in liver tissue of rats with type 2 diabetes: a metabolomics-based approach

Our aim was to study the metabolic effects of eight weeks of high-intensity interval training (HIIT) on the liver of rats with type 2 diabetes (T2D) using untargeted metabolomics. Twenty male Wistar rats, were divided into four groups (n = 5 per group): control (CTL), type 2 diabetes (DB), HIIT (EX), and type 2 diabetes + HIIT (DTX). A two months of a high-fat diet followed by a single dose of streptozotocin (35 mg/kg body weight) was used to induce T2D. Animals in the EX and DTX groups were trained for eight weeks (5 times per week, 4-10 running intervals at 80-100% of their maximum velocity). Metabolomic data were collected using proton nuclear magnetic resonance (¹H-NMR) to assess metabolic changes in the liver after training. Data were then pre-processed using ProMetab (MATLAB) for baseline correction, normalisation and binning. Fasting blood glucose (FBG) levels were analysed using a repeated-measures mixed ANOVA [i.e., time as the within-subject factor (Baseline - Month 0, Post-induction - Month 2, and Post-intervention - Month 4) and gruop (CTL, DB, HIIT, DTX) as the between-subject factor]. A one-way ANOVA with Tukey's post hoc test (p < 0.05) was applied to assess differences in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Multivariate analysis - using sparse partial least squares discriminant analysis (sPLS-DA) - was performed to identify key metabolites, followed by pathway analysis (MetaboAnalyst) to determine significantly affected metabolic pathways. DB group showed higher HOMA-IR than CTL and DTX groups (p < 0.05). Furthermore, distinct clustering patterns was shown for metabolites by multivariate analysis. Key altered metabolic pathways included valine, leucine, and isoleucine biosynthesis; glutathione metabolism; pantothenate and coenzyme A biosynthesis; fructose and mannose metabolism; glycine, serine, and threonine metabolism; cysteine and methionine metabolism; arginine biosynthesis; tyrosine metabolism; histidine metabolism; beta-alanine metabolism; propanoate metabolism; glycolysis/gluconeogenesis; phenylalanine, tyrosine, and tryptophan biosynthesis; arginine and proline metabolism; and thiamine metabolism. These results suggest that eight weeks of HIIT may reverse metabolic changes induced by T2D in the rat liver, potentially contributing to reduced FBG and HOMA-IR levels. Clinical trial number: Not applicable.

Review Article: GLP-1 Receptor Agonists and Glucagon/GIP/GLP-1 Receptor Dual or Triple Agonists-Mechanism of Action and Emerging Therapeutic Landscape in MASLD

BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is primarily managed through diet and lifestyle modifications. However, these behavioural interventions alone may not achieve disease regression or remission, and maintaining long-term adherence is challenging. Incretin mimetics and other gastrointestinal hormones targeting the pleiotropic pathophysiological pathways underlying MASLD have now emerged as promising disease-modifying therapies.

AIMS

This is a comprehensive review summarising the role of glucagon-like peptide-1 (GLP-1) receptor agonists and glucagon/glucose-dependent insulinotropic polypeptide (GIP)/GLP-1 receptor dual or triple agonists in the treatment of metabolic dysfunction-associated steatohepatitis (MASH).

METHODS

Only clinical trials with endpoints assessed by liver histology were included for a robust evaluation of therapeutic efficacy.

RESULTS

Recent evidence from phase 2 clinical trials for MASH demonstrated that pharmacological agents based on GLP-1 receptor agonism are effective in improving disease activity. Additionally, tirzepatide and survodutide showed potential clinical benefits in reducing fibrosis. Other cardiometabolic benefits observed include weight loss and improvements in glycaemic control and lipid profile. Adherence to treatment may be limited by gastrointestinal side effects, though they were found to be generally mild to moderate in severity. An interim analysis of the semaglutide phase 3 trial confirmed its efficacy in improving steatohepatitis and demonstrated its potential to improve fibrosis.

CONCLUSIONS

GLP-1 receptor agonists, alone or in combination with GIP and/or glucagon receptor agonists, represent promising, effective pharmacotherapies for the treatment of MASLD/MASH. Larger and longer-duration clinical trials are needed to further evaluate the efficacy and safety of GIP receptor and glucagon receptor agonism.

The Orphan Receptor GPR151: Discovery, Expression, and Emerging Biological Significance

G protein-coupled receptors (GPCRs) are among the most prominent druggable targets in the human genome, accounting for approximately 40% of marketed drugs. Despite this, current GPCR-targeted therapies address only about 10% of the GPCRs encoded in the genome. Expanding our knowledge of the remaining "orphan" GPCRs represents a critical frontier in drug discovery. GPR151 emerges as a compelling target due to its distinct expression in the habenula complex, spinal cord neurons, and dorsal root ganglia. This receptor is highly conserved across mammals and possesses orthologs in species such as zebrafish and chickens, underscoring its evolutionarily conserved role in fundamental mammalian processes. Although the precise function of GPR151 remains unknown, it has been strongly implicated in pain modulation and reward-seeking behavior. These attributes position GPR151 as a promising candidate for the development of targeted and specialized pharmacological therapies. This review summarizes the current literature on GPR151, including its discovery, structure, mechanisms, anatomical distribution, and functional roles, while also exploring potential directions for future research.

Glycolytic enzyme PFKFB4 governs lipolysis by promoting de novo lipogenesis to drive the progression of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is among the most aggressive malignancies, marked by high recurrence rates and limited treatment efficacy, especially in HBV-associated HCC (HBV-HCC). This subtype exhibits pronounced metabolic reprogramming, with lipid synthesis playing a pivotal role in driving tumor aggressiveness and therapeutic resistance. However, the molecular mechanisms underlying this metabolic shift remain unclear. In our study, analysis of the LIHC-TCGA database and comparisons between HCC tissues and adjacent peri-tumoral tissues revealed that 6-Phosphofructo-2-Kinase/Fructose-2,6-Biphosphatase 4 (PFKFB4) is significantly upregulated in HBV-HCC. Moreover, elevated PFKFB4 expression correlates with poorer prognosis and unfavorable overall survival among HBV-HCC patients. Functional assays demonstrated that PFKFB4 promotes HCC proliferation by enhancing glycolysis and de novo lipid synthesis. Notably, PFKFB4 not only increases glycolytic flux but also upregulates sterol regulatory element-binding protein 1 (SREBP1) expression via its enzymatic activity. Mechanistically, PFKFB4 suppresses phosphorylated AMP-activated protein kinase (p-AMPK) through enhanced aerobic glycolysis, which in turn stimulates the level of SREBP1. Collectively, these findings position PFKFB4 as a critical mediator of metabolic reprogramming in HBV-HCC and a promising therapeutic target.

Effects and Mechanisms of Steviol Glycosides on Glucose Metabolism: Evidence From Preclinical Studies

The natural sweeteners of steviol glycosides (SGs) have been widely used as a substitute for sugar due to their high sweetness, low-calorie properties, and potential health benefits. Some studies reported that SGs could regulate glucose metabolism and prevent Type 2 diabetes mellitus (T2DM); however, the detailed mechanisms remained further elucidated. Therefore, in this review, we aimed to systematically summarize the effects and mechanisms of SGs on glucose metabolism based on evidence from preclinical studies. We searched PubMed and Web of Science (up to March 31, 2024), and included a total of 40 animal and 5 cell studies for review. Results showed that SGs could improve glucose metabolism by enhancing insulin secretion, simulating insulin effects, improving insulin resistance, advancing key enzyme activities, or regulating gut microbiota. To conclude, if further validated in clinical trials and population studies, the sugar substitute of SGs may serve as a potential nutritional strategy for effective prevention and treatment of T2DM.

The association between stress hyperglycemia ratio and nonalcoholic fatty liver disease among U.S. adults: A population-based study

BACKGROUND AND AIM

The stress hyperglycemia ratio (SHR) offers a more nuanced understanding of glucose metabolism by factoring in the background glycemia through the component of Hemoglobin A1c. The association of SHR with cardiovascular and cerebrovascular diseases has been established, but the relationship between SHR and the risk of nonalcoholic fatty liver disease (NAFLD) remains unexplored. This study aimed to elucidate the relationship between the two among U.S. adults with diabetes or prediabetes.

METHODS AND RESULTS

A total of 1409 participants diagnosed with diabetes or prediabetes from the National Health and Nutrition Examination Survey (NHANES) 2017-2020 were included in this study. Multiple logistic regression models (ranging from unadjusted to fully adjusted), restricted cubic splines, and subgroup analyses were employed to determine the relationship between SHR and NAFLD risk and to assess the stability of this relationship across different populations. The average age of all participants was 54.65 years, with males accounting for 47.91 %, and the prevalence of NAFLD being 68.77 %. A fully adjusted logistic regression model indicated a positive association between SHR levels and the risk of NAFLD. Specifically, for each one standard deviation increase in SHR, the risk of NAFLD increased by 20 % (OR, 1.2; 95 % CI, 1.0-1.4). Both the trend test and the restricted cubic splines suggested a linear relationship between the two variables (p for trend <0.05, p for nonlinear = 0.390). Subgroup analysis demonstrated that this positive association remained consistent across most subgroups.

CONCLUSIONS

SHR was identified as a valuable index for predicting the risk of NAFLD among U.S. adults with diabetes or prediabetes.

Metabolic Sparks in the Liver: Metabolic and Epigenetic Reprogramming in Hepatic Stellate Cells Activation and Its Implications for Human Metabolic Diseases

The liver plays a fundamental role in metabolic homeostasis, integrating systemic fuel utilization with the progression of various metabolic diseases. Hepatic stellate cells (HSCs) are a key nonparenchymal cell type in the liver, which is essential for maintaining hepatic architecture in their quiescent state. However, upon chronic liver injury or metabolic stress, HSCs become activated, leading to excessive extracellular matrix deposition and pro-fibrotic signaling, ultimately positioning them as key players in liver pathology. Emerging evidence highlights the critical roles of metabolic reprogramming and epigenetic regulation in HSCs activation. HSCs activation is driven by both intrinsic fuel metabolism reprogramming and extrinsic metabolic cues from the microenvironment, while the metabolic intermediates actively reshape the epigenetic landscape, reinforcing fibrogenic transcriptional programs. In this review, we summarize recent advances in understanding how metabolic and epigenetic alterations drive HSCs activation, thereby shaping transcriptional programs that sustain fibrosis, and discuss potential therapeutic strategies to target these interconnected pathways in human metabolic diseases.

Carnitine supplementation improves insulin sensitivity and skeletal muscle acetylcarnitine formation in patients with type 2 diabetes

AIM/HYPOTHESIS

Recently, we reported that increasing free carnitine availability resulted in elevated skeletal muscle acetylcarnitine concentrations and restored metabolic flexibility in individuals who have impaired glucose tolerance. Metabolic flexibility is defined as the capacity to switch from predominantly fat oxidation while fasted to carbohydrate oxidation while insulin stimulated. Here we investigated if carnitine supplementation enhances the capacity of skeletal muscle to form acetylcarnitine and thereby improves insulin sensitivity and glucose homeostasis in patients with type 2 diabetes (T2DM).

METHODS

Thirty-two patients followed a 12-week L-carnitine treatment (2970 mg/day, orally). Insulin sensitivity was assessed by a two-step hyperinsulinemic-euglycemic clamp. In vivo skeletal muscle acetylcarnitine concentrations at rest and post-exercise (30 min, 70% Wmax) and intrahepatic lipid content (IHL) were determined by proton magnetic resonance spectroscopy (1H-MRS). All measurements were performed before and after 12 weeks of carnitine supplementation.

RESULTS

Compliance with the carnitine supplementation was good (as indicated by increased plasma-free carnitine levels (p < 0.01) and pill count (97.1 ± 0.7%)). Insulin-induced suppression of endogenous glucose production (31.9 ± 2.9 vs. 39.9 ± 3.2%, p = 0.020) and peripheral insulin sensitivity (Δ rate of glucose disappearance (ΔRd): 10.53 ± 1.85 vs. 13.83 ± 2.02 μmol/kg/min, p = 0.005) improved after supplementation. Resting (1.18 ± 0.13 vs. 1.54 ± 0.17 mmol/kgww, p = 0.008) and post-exercise (3.70 ± 0.22 vs. 4.53 ± 0.30 mmol/kgww, p < 0.001) skeletal muscle acetylcarnitine concentrations were both elevated after carnitine supplementation. Plasma glucose (p = 0.083) and IHL (p = 0.098) tended to be reduced after carnitine supplementation.

CONCLUSION

Carnitine supplementation improved insulin sensitivity and tended to lower IHL and fasting plasma glucose levels in patients with type 2 diabetes. Furthermore, carnitine supplementation increased acetylcarnitine concentration in muscle, which may underlie the beneficial effect on insulin sensitivity.

Cu(OH)2 nanopesticide induced liver dysfunction in mice by targeting lipoylated tricarboxylic acid cycle proteins via ferredoxin 1

Copper hydroxide [Cu(OH)2] nanopesticide is an emerging agrochemical known for its ability to mitigate bacterial and fungal damage to host organisms. However, its environmental exposure and potential toxicological effects have garnered significant attention. The liver is regarded as the primary organ for copper storage and utilization within the body. Here, the potential hepatic dyshomeostasis and metabolic dysfunction resulting from exposure to Cu(OH)2 nanopesticide for a month were investigated using the C57BL/6 mouse model. The findings demonstrated that Cu(OH)2 nanopesticide induced damage to the core functions of the mouse liver, evidenced by an impaired tissue microstructure, attenuated biochemical function, as well as disturbed bile acid synthesis and energy metabolism. The regulatory manner of Cu(OH)2 nanopesticide on the lipoylated proteins in the tricarboxylic acid (TCA) cycle by targeting ferredoxin 1 (FDX1) and its associated lipoic acid and iron-sulfur pathways, also shared genetic characteristics with the recently identified cuproptosis mechanism, providing a deeper understanding of the hepatoxic effects induced by this copper nanopesticide. These findings contribute valuable data for evaluating the hepatotoxicity of Cu(OH)2 nanopesticide, and further research into the molecular mechanisms is anticipated to enhance the identification of therapeutic targets for hepatic diseases related to copper metabolism.

Establishment and Characterization of Hepatocyte Line from Turbot (Scophthalmus maximus L.) and Its Application in the Study of Glucose Metabolism

The present study was to establish a hepatocyte line and investigate its role in glucose metabolism. A continuous cell line, THL (turbot hepatocyte line), was established from the liver tissue of turbot (Scophthalmus maximus L.). It has been successfully passaged more than 60 generations. The THL cells showed an epithelial-like morphology and the normal chromosome number was 44. Different methods were used to identify the hepatocytes. Periodic acid-Schiff (PAS) staining for THL cells was positive, and two key functional proteins of hepatocytes, cytokeratin- 18 (CK- 18) and albumin (ALB), were detected in THL cells. The results of CCK- 8 indicated that a medium containing 15 mM glucose showed optimal cell viability of THL. Conversely, elevating glucose concentrations beyond 50 mM markedly impaired THL cell viability. Western blot and qRT-PCR were employed to assess the gene and protein expression in cells treated with varying concentrations of glucose. The results of cells incubated with 0 mM, 15 mM, and 50 mM glucose concentrations showed that compared with the 0 mM glucose group, 15 mM glucose could increase the gene expression of glucokinase (gk) and decrease the gene expression of cytosolic phosphoenolpyruvate carboxykinase (cpepck), mitochondrial phosphoenolpyruvate (mpepck), glucose- 6-phosphatase 1 (g6pase1), forkhead box o1 (foxo1), and glucose-regulated protein 78 (grp78). Compared to 15 mM glucose treatment, the expression of gk in the 50 mM group was significantly decreased, but the expression of cpepck, mpepck, g6pase1, foxo1, and grp78 was significantly increased. Moreover, the protein expression of FoxO1 and GRP78 in 50 mM treatment group was significantly increased compared to that in the15 mM group. In the present study, it was found that excessive glucose level can activate the pathways of FoxO1-mediated gluconeogenesis and GRP78-mediated endoplasmic reticulum stress and reduce the glycolytic pathway, thus disrupting the glucose homeostasis in hepatocytes.

[Effects of intermittent fasting and sports performance: a narrative review]

Introduction

Recently, fasted exercise has generated interest for its potential to stimulate metabolic and performance adaptations. The present study aims to analyze the effects of fasting and fasted training on performance and metabolism, acutely and chronically. The databases Medline (PubMed), Physiotherapy Evidence Database (PEDro), Cochrane, and Google Scholar were searched. In total, 767 studies were identified. Of those, 51 studies were finally included. Acutely, exercise on fasting promotes fat oxidation at low and moderate intensities, while protein catabolism is not increased. Performance is not affected in efforts lower than 1 hour. Chronically, fasting generates greater efficiency in fat metabolism and the ability to regulate blood glucose in the long term, although it has not been possible to determine whether these findings improve sports performance. More research is needed in elite athletes, with high training loads and with a periodized approach to fasting.

Malus hupehensis leaves: a functional beverage for alleviating hepatic inflammation and modulating gut microbiota in diabetic mice

Malus hupehensis leaves (MHL), consumed as a daily beverage in Chinese folk tradition and recently recognized as a new food material, are abundant in polyphenols and bioactive compounds that demonstrate hypoglycemic, lipid-lowering, and anti-inflammatory effects. However, the antidiabetic mechanisms have not been fully elucidated. This study aimed to investigate the protective mechanisms of Malus hupehensis leaves' extract (MHLE) against type 2 diabetes mellitus (T2DM). The results showed that MHLE effectively ameliorated glucose and lipid metabolic abnormalities in db/db mice, and attenuated hepatic macrophage activation. Transcriptomic analysis of the liver revealed that MHLE primarily affects genes involved in inflammatory responses and inhibited the TLR4/MAPK pathway to reduce hepatic inflammation. Metagenomic sequencing identified changes in gut microbiota composition and showed that MHLE restored the abundance of Lachnospiraceae bacterium, Oscillospiraceae bacterium, and Clostridia bacterium while reducing the abundance of Escherichia coli, thereby ameliorating gut dysbiosis. The integrated regulation of metabolism, immune response, and the microbial environment by MHLE significantly alleviated symptoms of T2DM. This study offers strong scientific evidence for the potential use of MHL as a functional food.

RAP1A suppresses hepatic steatosis by regulating amino acid-mediated mTORC1 activation

Background & Aims

Metabolic dysfunction-associated steatotic liver disease (MASLD) is characterized by triglyceride (TG) build-up in hepatocytes; however, our understanding of the underlying molecular mechanisms is limited. Here, we investigated the role of hepatic GTPase RAP1A in MASLD and its more progressive form, metabolic dysfunction-associated steatohepatitis (MASH).

Methods

RAP1A was silenced or activated by AAV8-TBG-mediated gene expression or treating mice with a small molecule RAP1 activator (n = 4-12 per group). Primary hepatocytes were used to further probe the newly elucidated pathway. Liver samples from patients with MASH and control livers were analyzed for active RAP1A levels (n = 4 per group).

Results

Activation of hepatic RAP1A is suppressed in obese mice with MASLD and restoring its activity decreases liver steatosis. RAP1A activation lowers hepatic TG accumulation through decreasing sterol regulatory element-binding protein 1 (SREBP1) cleavage by inhibiting the mechanistic target of rapamycin complex 1 (mTORC1). The mechanism linking RAP1A activation to suppression of mTORC1 involves the lowering of membrane-bound amino acid transporters, which leads to reduced hepatocyte amino acid uptake, decreased intracellular amino acid levels, and inhibition of amino acid-mediated mTORC1 activation. Furthermore, we observed that active-RAP1A levels were decreased in mice fed a MASH-provoking diet (98% lower, p <0.01) and liver extracts from patients with MASH (86% lower, p <0.05). Accordingly, restoration of RAP1A activity in mice liver lowered liver fibrotic gene expression and prevented fibrosis formation, whereas RAP1A silencing promoted the progression of MASH.

Conclusions

Activation of hepatic RAP1A lowers MASLD and MASH formation by suppressing amino acid-mediated mTORC1 activation and decreasing cleaved SREBP1. These data provide mechanistic insight into amino acid-mediated mTORC1 regulation and raise the possibility that hepatic RAP1A may serve as a mechanistic node linking obesity with MASLD and MASH.

Impact and implications

Metabolic dysfunction-associated liver pathologies are inadequately treated with currently available therapy. Here we demonstrate that the small GTPase RAS-associated protein 1A (RAP1A) protects against liver steatosis and fibrosis development by decreasing hepatocyte amino acid levels, which results in lower mTORC1 activity and SREBP1 cleavage. The results may present new targets against metabolic dysfunction related liver diseases.

Mammary tumor development induces perturbation of liver glucose metabolism with inflammation and fibrosis

Cancer cells rely on glycolysis and lactic fermentation for ATP production, inducing an abnormal glucose uptake in tumors. However, it is largely unknown whether the increased tumor glucose consumption affects overall body glucose homeostasis including perturbation of the liver glucose production pathways. The effect of mammary tumor development on the liver metabolism pathway was examined by using a mouse model based on FVB/N wild-type (WT-SD) and FVB/N-Tg(MMTV-PyVT)634Mul/J mice (Tg-SD), who develop spontaneous mammary tumors. Blood and livers were analyzed for metabolic changes, by measuring histological staining, signaling, and insulin sensitivity. Tg-SD mice developed mammary tumors with an average weight of 6 g, and cancer development increased total food intake without impacting body weight gain. Tumor development did not affect blood glycemia and lactate levels but increased insulin and homeostasis model assessment of insulin resistance (HOMA-IR) index (P = 0.06). In the liver, Tg-SD mice with tumors exhibited a decrease in glycogen content and an increase in gluconeogenesis gene expression, as G6pc, Pgc1α, and Foxo1 (P < 0.05), as well as Pepck and Ldha (P < 0.01). Moreover, the phosphorylation of AMPK and AKT was significantly decreased (P < 0.01 and P < 0.05, respectively). Surprisingly, liver fibrosis was markedly increased in Tg mice (P < 0.05) alongside elevated inflammatory gene expression, such as IL1β (P < 0.01) or IL6 (P < 0.05). Here, we found that the development of non-metastatic mammary tumors using the MMTV-PyMT mouse model disrupts liver function through the development of inflammation, fibrosis, and metabolic perturbation, including an increase in glucose production and insulin resistance. Finally, these observations unravel a previously unknown metabolic cross talk between the tumors and the liver.NEW & NOTEWORTHY This work demonstrates that the spontaneous development of non-metastatic mammary tumors triggers hepatic activation of endogenous glucose production pathways, coinciding with the onset of insulin resistance. This finding suggests a significant cross talk between tumors and the liver during tumorigenesis, aiming at enhancing glucose production to meet the elevated energy demands of the tumor. Understanding this interaction could provide insights into metabolic alterations associated with cancer and lead to potential therapeutic targets to inhibit tumor metabolism.

Notch1 Signalling Is Downregulated by Aerobic Exercise, Leading to Improvement of Hepatic Metabolism in Obese Mice

BACKGROUND AND AIMS

Notch1 protein plays a significant role in hepatic metabolism, as evidenced by its correlation with insulin resistance in the livers of obese individuals, making it an intriguing research target. Therefore, this study aims to investigate the impact of aerobic exercise on Notch1 pathways in the hepatic tissue of obese mice and its role in controlling hepatic metabolism.

METHODS

Therefore, we conducted a cross-sectional study utilising liver biopsies from lean and obese humans, as well as an intervention study involving mice subjected to a high-fat diet. The obese-trained mice group underwent a treadmill-running protocol for 4 weeks.

RESULTS

Our findings revealed that obese individuals exhibited increased NOTCH1 mRNA levels compared to lean subjects. The detrimental effects of Notch1 signalling were confirmed by Notch1-overexpressed HepG2 cell lines. Obese mice with higher hepatic Notch1 signalling demonstrated a reduction in this pathway when subjected to a 4-week treadmill running. Another benefit noticed in this trained group was the amelioration of insulin resistance, as well as a reduction in pyruvate intolerance and gluconeogenic enzymes. Additionally, we observed that these protective findings were accompanied by a decrease in mTORC1 pathway activity and lipid accumulation in the liver. Pharmacological inhibition of Notch1 in obese mice led to an increase in mitochondrial respiration in the liver.

CONCLUSIONS

We conclude that Notch1 signalling may be a potentially useful therapeutic target in obesity, while aerobic exercise training suppresses the Notch1 pathway in the liver, contributing to the regulation of hepatic glucose and lipid metabolism in obese mice.

Glucose metabolism in the perfused liver did not improve with resistance training in male Swiss mice under caloric restriction

CONTEXT

Energy homeostasis is a primary factor for the survival of mammals. Many tissues and organs, among which is the liver, keep this homeostasis in varied circumstances, including caloric restriction (CR) and physical activity.

OBJECTIVE

This study investigated glucose metabolism using the following groups of eight-week-old male Swiss mice: CS, sedentary and fed freely; RS, sedentary and RT, trained, both under 30% CR (n = 20-23 per group).

RESULTS

Organs and fat depots of groups RS and RT were similar to CS, although body weight was lower. CR did not impair training performance nor affected systemic or hepatic glucose metabolism. Training combined with CR (group RT) improved in vivo glucose tolerance and did not affect liver gluconeogenesis.

CONCLUSIONS

The mice tolerated the prolonged moderate CR without impairment of their well-being, glucose homeostasis, and resistance training performance. But the higher liver gluconeogenic efficiency previously demonstrated using this training protocol in mice was not evidenced under CR.

Vitronectin stimulates hepatic gluconeogenesis by activating the cAMP/PKA/CREB axis in the liver

Vitronectin, a protein derived the human placenta, has been identified as an inducer of insulin resistance in trophoblast cells in gestational diabetes mellitus (GDM). As a secreted protein, vitronectin may have systemic effects on dysregulated glucose metabolism in GDM. To address this speculation, we generated a GDM mouse model using high-fat diet-induced obese mice. Consistent with findings in placentas of GDM patients, GDM mouse placentas showed higher vitronectin expression, accompanied by increased serum vitronectin levels. Reduced insulin signaling transduction was observed in both the placentas and livers of GDM mice, along with enhanced hepatic gluconeogenesis. To further explore the role of vitronectin in hepatic gluconeogenesis, we constructed an adeno-associated virus expressing Vtn (AAV-VTN), which was administered to mice via tail vein injection. In AAV-VTN-treated mice, glucose production from exogenous pyruvate increased, and the expression of gluconeogenic genes in the liver was upregulated, indicating that hepatic gluconeogenesis was stimulated by vitronectin. Mechanistically, vitronectin binds to its receptor CD51/61, activating the cAMP/PKA/CREB axis in hepatocytes, thereby promoting hepatic gluconeogenesis. In summary, our findings suggest that placenta-derived vitronectin plays a critical role in inducing insulin resistance in the liver in GDM. Moreover, vitronectin stimulates hepatic gluconeogenesis through activation of the cAMP/PKA/CREB axis. These results point to vitronectin as a potential therapeutic target for managing hyperglycemia in GDM.

Clerodane diterpenoids from the vine stems of Fibraurea recisa Pierre and their hepatic gluconeogenesis inhibitory activity

Fibraurea recisa Pierre is a vine plant and its vine stems are used as a traditional Chinese medicine to treat heat toxin, constipation, diarrhea, sore throat, eye inflammation, carbuncles, and skin ulcers. The alkaloid chemical composition of this plant has been extensively studied; however, investigations into non-alkaloid components remain limited. In this study, phytochemical studies of the vine stems of F. recisa were conducted, leading to the isolation and identification of twenty highly oxidized clerodane diterpenoids, including ten previously undescribed compounds, designated fibrecins A-J (1-10). The structures and absolute configurations of 1-10 were determined through comprehensive spectroscopic methods (IR, HRESIMS, 1D and 2D NMR), electronic circular dichroism data, and single-crystal X-ray diffraction. Notably, compounds 1 and 2 are rare 18-nor-clerodane diterpenoids. Excessive hepatic gluconeogenesis is an important cause of hyperglycemia and type 2 diabetes mellitus. Herein, compounds 1, 9, 14, and 15 were found to exhibit moderate hepatic gluconeogenesis inhibitory activity in primary mouse hepatocytes, suggesting that these compounds might have potential effect on ameliorating the hyperglycaemia.

Controversy and multiple roles of the solitary nucleus receptor Nur77 in disease and physiology

Neuron-derived clone 77 (Nur77), a member of the orphan nuclear receptor family, is expressed and activated rapidly in response to diverse physiological and pathological stimuli. It exerts complex biological functions, including roles in the nervous system, genome integrity, cell differentiation, homeostasis, oxidative stress, autophagy, aging, and infection. Recent studies suggest that Nur77 agonists alleviate symptoms of neurodegenerative diseases, highlighting its potential as a therapeutic target in such conditions. In cancer, Nur77 demonstrates dual roles, acting as both a tumor suppressor and promoter, depending on the cancer type and stage, making it a controversial yet promising anticancer target. This review provides a structured analysis of the functions of Nur77, focusing on its physiological and pathological roles, therapeutic potential, and existing controversies. Emphasis is placed on its emerging applications in neurodegenerative diseases and cancer, offering key insights for future research and clinical translation.

Design of self-assembled micelles based on natural dual-targeting strategies and evaluation of their anti-liver cancer effects as drug delivery systems

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in the world and in China, Most patients are already in an advanced stage at the time of diagnosis, and the chance of complete surgical resection is lost, therefore, drug treatment is particularly important. Angelica sinensis polysaccharide (ASP) has natural liver-targeting properties, berberine (BBR) is a lipophilic cation with anticancer activities and mitochondrial-targeting properties, and honokiol (HNK) has mitochondria-dependent anticancer effects against cancer. Therefore, the aim of the present work was to synthesize Angelica sinensis polysaccharide-berberineamphiphilic polymer (ASP-SS-BBR) loaded with HNK to prepare the micelles ASP-BBR-PM@HNK to improve the hepatic targeting ability of the nanoparticles and the mitochondrial targeting ability in HCC cells and to enhance the anti-HCC effect of HNK. The findings of this study demonstrate the successful synthesis of ASP-BBR-PM@HNK, characterized by a particle size of 48.6 ± 1.13 nm. The formulation exhibits commendable stability, a sustained-release profile, and the capability for glutathione (GSH)-responsive release. ASP-BBR-PM@HNK is efficiently internalized by HepG2 cells, exhibiting the highest rate of cell inhibition. Additionally, the use of Gal and Man as receptor blockers confirmed the formulation's superior targeting capabilities, including exceptional mitochondrial targeting. Subsequent in vivo experiments employing BALB/c nude mice as a model further corroborated these experimental outcomes. This research has successfully developed an effective natural dual-targeting system, offering a novel approach for the precise treatment of liver cancer.

Size-Dependent Cytotoxicity and Multi-Omic Changes Induced by Amorphous Silicon Nanoparticles in HepG2 Cells

(1) Background: Silica nanoparticles (SiO2 NPs) have a high potential for human exposure and tend to accumulate in the liver. This study aimed to explore the size-dependent cytotoxicity induced by SiO2 NPs and identify key molecular pathways at the in vitro level through proteomics, metabolomics, and a combination of multiple omics methods. (2) Methods: The human hepatoma cells (HepG2) cells were exposed to SiO2 NPs of three different sizes (60, 250, and 400 nm) at doses of 0, 12.5, 25, 50, 100, and 200 μg/mL for 24 h. (3) Results: Exposure to 60 nm SiO2 NPs induced more reduction in cell viability than the other two larger-scale particles. Changes in the metabolomic and proteomic profiles of HepG2 cells induced by SiO2 NPs were also size-dependent. The main pathways that were significantly affected in the 60 nm SiO2 NPs treatment group represented cholesterol metabolism in proteomics and central carbon metabolism in metabolomics. Moreover, common enrichment pathways between differential proteins and metabolites included protein digestion and absorption and vitamin digestion and absorption. (4) Conclusions: Exposure to SiO2 NPs could induce size-dependent cytotoxicity and changes in proteomics and metabolomics, probably mainly by interfering with energy metabolism pathways.

Plant Derived Exosome-Like Nanoparticles and Their Therapeutic Applications in Glucolipid Metabolism Diseases

Plant derived exosome-like nanoparticles (PELNs) are membrane structures isolated from different plants, which encapsulate many active substances such as proteins, lipids, and nucleic acids, which exert a substantial influence on many physiological processes such as plant growth and development, self-defense, and tissue repair. Compared with synthetic nanoparticles and mammalian cell derived exosomes (MDEs), PELNs have lower toxicity and immunogenicity and possess excellent biocompatibility. The intrinsic properties of PELNs establish a robust basis for their applications in the therapeutic management of a diverse array of pathologies. It is worth mentioning that PELNs have good biological targeting, which promotes them to load and deliver drugs to specific tissues, offering a superior development pathway for the construction of a new drug delivery system (DDS). Glucose and lipid metabolism is a vital life process for the body's energy and material supply. The maintenance of homeostatic balance provides a fundamental basis for the body's ability to adjust to modifications in both its internal and external environment. Conversely, homeostatic imbalance can lead to a range of severe metabolic disorders. This work provides a comprehensive overview of the extraction and representation methods of PELNs, their transportation and storage characteristics, and their applications as therapeutic agents for direct treatment and as delivery vehicles to enhance nutrition and health. Additionally, it examines the therapeutic efficacy and practical applications of PELNs in addressing abnormalities in glucose and lipid metabolism. Finally, combined with the above contents, the paper summarizes and provides a conceptual framework for the better application of PELNs in clinical disease treatment.

The hypoglycemic effect of mulberry (Morus atropurpurea) fruit lacking fructose and glucose by regulation of the gut microbiota

Mulberries are known to be rich in hypoglycemic active substances such as anthocyanins and dietary fiber, which primarily aid in regulating gut microbiota. However, their high sugar content, such as fructose, hinders their application in hypoglycemic functional foods. This research utilized microbial fermentation technology to remove the fructose and glucose in mulberries (FM), subsequently evaluating their hypoglycemic properties and balancing gut microbiota. Results indicated that administering varying doses of FM to type 2 diabetic mice for five weeks notably decreased blood sugar and insulin levels, improved dyslipidemia and insulin resistance, enhanced antioxidant capacity, repaired organ damage, and regulated hypoglycemic activity by influencing mRNA expression of key signaling factors in the PI3K/Akt and AMPK pathways. Analysis of the intestinal microbiota composition revealed that FM can modulate specific bacterial populations, increasing beneficial bacteria like Lactobacillus, Bifidobacterium and Akkermansia while inhibiting harmful bacteria like Escherichia-Shigella and Helicobacter. This restoration of the intestinal microecological balance helped regulate host sugar metabolism homeostasis and affect the secretion of short chain fatty acid (SCFA) synthase in the gut microbiota to increase the production of SCFAs. These findings offer significant support for the potential use of FM in the treatment of diabetes.

Insulin resistance and cancer: molecular links and clinical perspectives

The association between insulin resistance (IR), type 2 diabetes mellitus (T2DM), and cancer is increasingly recognized and poses an escalating global health challenge, as the incidence of these conditions continues to rise. Studies indicate that individuals with T2DM have a 10-20% increased risk of developing various solid tumors, including colorectal, breast, pancreatic, and liver cancers. The relative risk (RR) varies depending on cancer type, with pancreatic and liver cancers showing a particularly strong association (RR 2.0-2.5), while colorectal and breast cancers demonstrate a moderate increase (RR 1.2-1.5). Understanding these epidemiological trends is crucial for developing integrated management strategies. Given the global rise in T2DM and cancer cases, exploring the complex relationship between these conditions is critical. IR contributes to hyperglycemia, chronic inflammation, and altered lipid metabolism. Together, these factors create a pro-tumorigenic environment conducive to cancer development and progression. In individuals with IR, hyperinsulinemia triggers the insulin-insulin-like growth factor (IGF1R) signaling pathway, activating cancer-associated pathways such as mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PIK3CA), which promote cell proliferation and survival, thereby supporting tumor growth. Both IR and T2DM are linked to increased morbidity and mortality in patients with cancer. By providing an in-depth analysis of the molecular links between insulin resistance and cancer, this review offers valuable insights into the role of metabolic dysfunction in tumor progression. Addressing insulin resistance as a co-morbidity may open new avenues for risk assessment, early intervention, and the development of integrated treatment strategies to improve patient outcomes.

Liver-derived Neuregulin1α stimulates compensatory pancreatic β cell hyperplasia in insulin resistance

Compensatory pancreatic islet hyperplasia is an adaptive response to increased systemic insulin demand, although factors meditating this response remain poorly understood. Here, we show that a liver-derived secreted protein, Neuregulin1α, promotes compensatory proliferation of pancreatic β cells in type 2 diabetes. Liver Neuregulin1α expression and serum Neuregulin1α levels increase in male mice fed an obesity-inducing diet. Male mice lacking either Neuregulin1 in liver or its receptor, ErbB3, in β cells deteriorate systemic glucose disposal due to impaired β cell expansion with reduced insulin secretion when fed the obesity-inducing diet. Mechanistically, Neuregulin1α activates ERBB2/3-ERK signaling to stimulate β cell proliferation without altering glucose-stimulated insulin secretion potential. In patients with metabolic dysfunction-associated steatotic liver disease (MASLD) and obesity but without type 2 diabetes serum Neuregulin1α levels increase, while in patient with MASLD and type 2 diabetes show markedly reduced levels of Neuregulin1α. These results suggest that Neuregulin1α serves as a hepatokine that can expand functional β cell mass in type 2 diabetes.

Chronic Exposure to Environmental Concentrations of Tetrabromobisphenol A Disrupts Insulin and Lipid Homeostasis in Diet-Induced Obese Mice

Tetrabromobisphenol A (TBBPA), a widely used brominated flame retardant in consumer products, has raised significant health concerns. However, the long-term metabolic effects of chronic exposure to environmentally relevant TBBPA concentrations, particularly in the context of modern high-calorie diets, remain poorly understood. Here, we show that C57BL/6J mice fed a high-fat diet and exposed to 20 or 50 nmol/kg/day TBBPA for 120 days exhibited increased body weight, aggravated fat accumulation, impaired glucose tolerance, insulin resistance, and dyslipidemia. Mechanistic investigations revealed that TBBPA exposure led to decreased norepinephrine levels, consequently reducing energy expenditure. It disrupts hepatic insulin signaling and upregulates G6Pase, thereby increasing the level of liver glucose production. Furthermore, TBBPA enhances hepatic cholesterol synthesis by elevating protein levels of HMGCR, which is the rate-limiting enzyme in cholesterol biosynthesis. This effect is mediated through increased expression of USP20, a specific deubiquitinating enzyme for HMGCR. Additionally, TBBPA modestly enhances fatty acid biosynthesis without significantly affecting lipolysis or fatty acid oxidation. Our research reveals novel molecular pathways through which environmental TBBPA exposure disrupts metabolic balance, potentially exacerbating obesity-related health issues. These findings highlight the synergistic effects between environmental pollutants and modern calorie-dense diets on metabolic health, emphasizing the importance of considering multiple factors in obesity-related disorders.

Roles of Gut Microbiota Metabolites and Circadian Genes in the Improvement of Glucose and Lipid Metabolism in KKAy Mice by Theabrownin

Theabrownin (TB), a prominent pigment in fermented dark tea, exhibits beneficial effects on adiposity reduction. Our study revealed that TB derived from Fu brick tea significantly lowered fasting blood glucose levels and insulin resistance in obese/diabetic KKAy mice. Furthermore, TB demonstrated potent anti-inflammatory effects in the liver, adipose tissue, and intestines, as well as enhancing intestinal integrity. Additionally, TB was found to inhibit hepatic gluconeogenesis and promote fatty acid oxidation. Notably, TB altered gut metabolites, particularly l-palmitoylcarnitine, which showed an elevation in serum, liver, and adipose tissue following TB intervention. l-Palmitoylcarnitine reduced gluconeogenesis in primary hepatocytes and decreased lipid deposition in both primary hepatocytes and 3T3-L1 adipocytes in vitro. However, these effects were abolished when the circadian gene Period 3 (Per3) was knocked down. Our findings suggest that l-palmitoylcarnitine may play a crucial role in improving TB-mediated glucose homeostasis and lipid metabolism by regulating Per3.

Constitutively active glucagon receptor drives high blood glucose in birds

The maintenance of blood glucose, the body's primary source of energy, is indispensable for overall health and metabolic homeostasis. It is regulated predominantly by the glucagon receptor family which is highly conserved in vertebrates1-4. Compared with other vertebrates, avian blood glucose levels are relatively high5,6, and blood glucose regulatory mechanisms in birds have remained unclear. Here we show that high hepatic expression of the avian glucagon receptor (GCGR) in association with constitutively active Gs signalling is dependent on the interaction of different domains. In vivo experiments showed that expression of constitutively active GCGR in hepatic cells led to correspondingly high blood glucose, rapid hepatic lipid utilization and high metabolic rates via downstream signalling pathway activation in fish, reptiles, birds and mammals. Furthermore, we identified a point mutation proximal to the GCGR gene region in chicken that resulted in reduced GCGR mRNA expression and increased body weight. Overexpressing a natural human GCGR variant (HsGCGR(H339R)) with modest constitutive activity in mice demonstrated that high expression of this variant increased blood glucose concentration and reduced body weight. In sum, we find that high expression and constitutive activity of GCGR may have contributed to the evolution of flight in the ancestors of birds.

Dual targeting PPARα and NPC1L1 metabolic vulnerabilities blocks tumorigenesis

Dysregulated lipid metabolism is linked to tumor progression. In this study, we identified Niemann-Pick C1-like 1 (NPC1L1) as a downstream effector of PKM2. In breast cancer cells, PKM2 knockout (KO) enhanced NPC1L1 expression while downregulating peroxisome proliferator-activated receptor α (PPARα) signaling pathway. PPARα and nuclear factor-E2 p45-related factor 1/2(Nrf1/2) are transcription factors regulating NPC1L1. In vitro PKM2 KO enhanced recruitment of Nrf1/2 to the NPC1L1 promoter region. Fenofibrate, a PPARα activator, promoted NPC1L1 expression; ezetimibe, an NPC1L1 inhibitor and effective Nrf2 activator, also elevated NPC1L1 expression. Combined administration of fenofibrate and ezetimibe significantly induced cytoplasmic vacuolation, and cell apoptosis. Mechanistically, this combined administration activated inositol required enzyme 1α(IRE1α) and produced the spliced form of X-box binding protein (XBP1s), which in turn enhanced lysine demethylase 6B (KDM6B) transcription. XBP1s interacts with KDM6B to activate genes involved in the unfolded protein response by demethylating di- and tri-methylated lysine 27 of histone H3 (H3K27), consequently increasing H3K27 acetylation levels in breast cancer cell lines. Fenofibrate and ezetimibe synergistically inhibited tumor growth in vivo. Our findings reveal that dual targeting of PPARα and NPC1L1 may represent a novel therapeutic regimen for breast cancer therapy.

Glucokinase: from allosteric glucose sensing to disease variants

Human glucokinase (GCK) functions as a glucose sensor in the pancreas and liver, where GCK activity regulates insulin secretion and glycogen synthesis, respectively. GCK's low affinity for glucose and the sigmoidal substrate dependency of enzymatic turnover enables it to act as a sensor that makes cells responsive to changes in circulating glucose levels. Its unusual kinetic properties are intrinsically linked to the enzyme's conformational dynamics. Accordingly, genetic variants that alter the dynamics or other aspects of GCK function are linked to three glucose homeostasis diseases. In this review, we describe the enzyme GCK, focusing on its role as a glucose sensor, its unusual kinetic properties, and recent large-scale efforts to assess GCK variant effects.

Is the triglyceride-glucose index ready for cardiovascular risk assessment?

AIMS

Insulin resistance is a major risk factor for cardiovascular disease. Thus, early identification of insulin resistance is important for classifying individuals at high cardiovascular risk. All the tools commonly used in epidemiological studies and clinical practice to assess insulin resistance require measuring insulin levels, which is a limitation. Hence, simpler methods have been proposed to overcome these limitations. One of the most promising is the triglyceride-glucose index. Therefore, this narrative review focuses on the most significant epidemiological findings concerning the relationship between the triglyceride-glucose index and cardiovascular risk. Furthermore, it also highlights this new tool's strengths, limitations, and perspectives for assessing cardiovascular risk.

DATA SYNTHESIS

Even though the assessment of this index is relatively recent, there are numerous papers on this topic, and their number is constantly increasing. Observational studies have shown a substantial positive association between the triglyceride-glucose index and cardiovascular risk, although some conflicting results have been observed.

CONCLUSIONS

The index is strongly associated with cardiovascular mortality and cardiovascular risk factors. However, some gaps need to be addressed.

Improved Afternoon Hepatic Glucose Disposal and Storage Requires Morning Engagement of Hepatic Insulin Receptors

Glucose tolerance improves significantly upon consuming a second, identical meal later in the day (second-meal phenomenon). We previously established that morning hyperinsulinemia primes the liver for increased afternoon hepatic glucose uptake (HGU). Although the route of insulin delivery is an important determinant of the mechanisms by which insulin regulates liver glucose metabolism (direct hepatic vs. indirect insulin action), it is not known whether insulin's delivery route affects the second-meal response. To determine whether morning peripheral insulin delivery (as occurs clinically, i.e., subcutaneously) can enhance afternoon HGU, conscious dogs were treated in the morning with insulin delivered either via the portal vein or peripherally (leg vein), while glucose was infused to maintain euglycemia. Consequently, arterial insulin levels increased similarly in both groups, but relative hepatic insulin deficiency occurred with peripheral insulin delivery. In the afternoon, all animals were challenged with the same hyperinsulinemic-hyperglycemic clamp to simulate identical postprandial-like conditions. The substantial enhancement of HGU in the afternoon caused by morning portal vein insulin delivery was lost when insulin was delivered peripherally. This indicates that morning insulin does not cause the second-meal phenomenon via its indirect actions on the liver but, rather, through direct activation of hepatic insulin signaling.

ARTICLE HIGHLIGHTS

Morning insulin delivery primes the liver for increased hepatic glucose uptake (HGU) later in the day, but until now, the mechanism (direct hepatic and/or indirect insulin action) remained unclear. This study compared insulin infusion via endogenous (hepatic portal vein) and clinical (peripheral) routes to assess their impact on afternoon hepatic glucose disposal. Arterial hyperinsulinemia in the morning, without a concomitant increase in insulin at the liver, failed to induce a significant enhancing effect on afternoon HGU and glycogen storage, unlike morning hepatic portal vein insulin delivery, which did. These findings highlight the importance of achieving appropriate hepatic insulin exposure in the morning to effectively prime the liver for enhanced glucose disposal later in the day.

LGR4 is a key regulator of hepatic gluconeogenesis

AIMS/HYPOTHESIS

Emerging evidence underscored the significance of leucine-rich repeat-containing G protein-coupled receptor (LGR) 4 in endocrine and metabolic disorders. Despite this, its role in LGR4 in hepatic glucose metabolism remains poorly understood. In this study we set out to test whether LGR4 regulates glucose production in liver through a specific signaling pathway.

METHODS

Hepatic glucose production and gluconeogenic gene expressions were detected after silence of LGR4 in three obese mice models. Then, whole-body LGR4-deficient (LGR4 KO) mice, liver-specific LGR4 knockout (LGR4LKO) mice, and liver-specific LGR4 overexpression (LGR4LOV) mice were generated, in which we analyzed the effects of LGR4 on hepatic glucose metabolism upon HFD feeding, among which live imaging and quantitative analysis of hepatic phosphoenolpyruvate carboxykinase (PEPCK)-luciferase activity were conducted.

RESULTS

LGR4 expression was significantly upregulated in the liver of three obese mouse models, and presented dynamic expression patterns in response to nutritional fluxes. We utilized global and liver-specific LGR4 knockouts (LGR4LKO), along with adenoviral-mediated LGR4 knockdown in mice, to show improved glucose tolerance and decreased hepatic gluconeogenesis. Specifically, the expression of rate-limiting gluconeogenic enzymes, PEPCK was significantly downregulated. Conversely, mouse model with adenovirus-mediated LGR4 overexpression (LGR4LOV) exhibited elevated gluconeogenesis and PEPCK expression and reversed the suppression observed in LGR4 knockout models. Notably, neither RANKL nor PKA signaling pathways, which were reported to take part in LGR4's function, were involved in the process of LGR4 regulating PEPCK. Instead, TopFlash reporter system and inhibitors application suggested that LGR4's influence on hepatic gluconeogenesis operates through the canonical Wnt/β-catenin/TCF7L2 signaling pathway.

CONCLUSIONS/INTERPRETATION

Overall, these findings underscore a novel mechanism by which LGR4 regulates hepatic gluconeogenesis, presenting a potential therapeutic target for diabetes management.

Hepatic Metabolic Memory Triggered by AM Exposure to Glucagon Alters Afternoon Glucose Metabolism

The second meal effect describes an improved glycemic response observed after consuming a second identical meal. We previously showed that morning (AM) exposure to hyperinsulinemia primes the liver for enhanced hepatic glucose uptake and glycogen storage in the afternoon (PM), with no significant effect on PM non-hepatic glucose uptake. Given that meals often trigger both insulin and glucagon secretion, we aimed to determine if AM hyperglucagonemia alters the priming effect of AM hyperinsulinemia on PM hepatic glucose metabolism. To test this, dogs were exposed to a 4h AM hyperinsulinemic-euglycemic clamp, with insulin delivered in a pattern mimicking the insulin profile observed earlier during a 4h AM duodenal glucose infusion. This period of hyperinsulinemia was paired with either basal (Prime, n=8) or elevated (Prime + ↑GGN, n=8) glucagon, maintaining a consistent insulin-to-glucagon molar ratio throughout the AM clamp. After a 1.5h rest period, the dogs underwent a 2.5h PM hyperinsulinemic-hyperglycemic clamp, during which glucose, insulin, and glucagon levels, along with the artery-to-portal vein glucose gradient, were carefully controlled to replicate postprandial conditions. During the PM clamp, the mean net hepatic glucose uptake (NHGU) in the Prime + ↑GGN group was only 59% of that in the Prime group (3.6±0.4 vs. 6.1±0.6 mg/kg/min, P<0.0027, respectively). Additionally, PM direct glycogen synthesis was two-fold greater in the Prime group compared to the Prime + ↑GGN group (3.2±0.7 vs. 1.5±0.2 mg/kg/min, P<0.0014, respectively). The observed difference in PM NHGU between the groups was not due to enhanced PM hepatic glucose uptake (HGU), which was similar in both groups (5.7±0.5 mg/kg/min in the Prime group vs. 5.2±0.3 mg/kg/min in the Prime + ↑GGN group), but rather a prolonged effect of AM hyperglucagonemia on PM hepatic glucose production (HGP) (-0.3±0.3 mg/kg/min in the Prime group vs. 1.7±0.4 mg/kg/min in the Prime + ↑GGN group, P<0.0072). This increase in PM HGP in the Prime + ↑GGN group was not driven by differences in PM gluconeogenic flux but by futile glucose cycling between glucose and glucose-6-phosphate, as well as hepatic glycogen storage and breakdown. In summary, these findings suggest that morning exposure to elevated glucagon shifts the insulin-driven priming effect on afternoon hepatic glucose metabolism by promoting sustained glucose cycling at the expense of glycogen synthesis and glycolysis, leading to persistent HGP despite identical PM insulin, glucose, and glucagon levels.

Liver ALKBH5 regulates glucose and lipid homeostasis independently through GCGR and mTORC1 signaling

Maintaining glucose and lipid homeostasis is crucial for health, with dysregulation leading to metabolic diseases such as type 2 diabetes mellitus (T2DM) and metabolic dysfunction-associated fatty liver disease (MAFLD). This study identifies alkylation repair homolog protein 5 (ALKBH5), an RNA N6-methyladenosine (m6A) demethylase, as a major regulator in metabolic disease. ALKBH5 is up-regulated in the liver during obesity and also phosphorylated by protein kinase A, causing its translocation to the cytosol. Hepatocyte-specific deletion of Alkbh5 reduces glucose and lipids by inhibiting the glucagon receptor (GCGR) and mammalian target of rapamycin complex 1 (mTORC1) signaling pathways. Targeted knockdown of hepatic Alkbh5 reverses T2DM and MAFLD in diabetic mice, highlighting its therapeutic potential. This study unveils a regulatory mechanism wherein ALKBH5 orchestrates glucose and lipid homeostasis by integrating the GCGR and mTORC1 pathways, providing insight into the regulation of metabolic diseases.

Prediabetes remission to reduce the global burden of type 2 diabetes

Prediabetes is a highly prevalent and increasingly common condition affecting a significant proportion of the global population. The heterogeneous nature of prediabetes presents a challenge in identifying individuals who particularly benefit from lifestyle or other therapeutic interventions aiming at preventing type 2 diabetes (T2D) and associated comorbidities. The phenotypic characteristics of individuals at risk for diabetes are associated with both specific risk profiles for progression and a differential potential to facilitate prediabetes remission and reduce the risk of future T2D. This review examines the current definition and global prevalence of prediabetes and evaluates the potential of prediabetes remission to reduce the alarming increase in the global burden of T2D.

Mitogen-Activated Protein Kinase Phosphatase-2 Deletion Promotes Hyperglycemia and Susceptibility to Streptozotocin-Induced Diabetes in Female Mice In Vivo

The development of type 2 diabetes (T2D) is largely dependent on the maintenance of pancreatic islet function and mass. Sexual dimorphism in T2D is evident in many areas, such as pathophysiology, treatment, and prevention. Mitogen-activated protein kinase phosphatase-2 (MKP-2) has a distinct role in the regulation of cell proliferation and the development of metabolic disorders. However, whether there is a causal relationship between MKP-2 and diabetes onset is unclear. The aim of this study was to determine the role of MKP-2 in the regulation of whole-body glucose homeostasis and the impact on pancreatic islet function using streptozotocin-induced pancreatic injury. Here, we show that female mice with whole-body deletion of MKP-2 exhibit hyperglycemia in mouse models treated with multiple low doses of streptozotocin (STZ). In comparison, both male MKP-2 wild-type and knockout mice were hyperglycemic. Consistent with the hyperglycemia, female MKP-2-deficient mice exhibited reduced islet size. Under T2D conditions, MKP-2-deficient mice display enhanced pancreatic JNK and ERK phosphorylation that is associated with the downregulation of genes important for pancreatic islet development and function, Pdx-1 and MafA. Furthermore, we found impaired metabolic flux in adipose tissue that is consistent with hyperglycemia and dysfunctional pancreas. MKP-2 deletion results in reduced Akt activation that is associated with increased adiposity and insulin resistance in female MKP-2 KO mice. These studies demonstrate the critical role of MKP-2 in the development of T2D diabetes in vivo. This suggests that MKP-2 may have a gender-specific role in diabetes development. This discovery raises the possibility that postmenopausal prevention of T2D may benefit from the activation of MKP-2 activity in islet cells.

Transcriptome analysis to explore the molecular mechanisms involved in the dormancy-arousal process in Pomacea canaliculata (Lamarck, 1819)

The apple snail, Pomacea canaliculata (Lamarck, 1819), a freshwater snail listed as a pernicious invasive alien species by the World Conservation Union (IUCN), has caused serious agricultural and ecological harm worldwide. This species has inflicted significant agricultural and ecological damage on a global scale. Under conditions of extreme environmental stress, the apple snail enters a state of dormancy and remains in this dormant phase until environmental conditions become favorable again, which serves as a crucial survival strategy. In our study, we subjected apple snails to 30 days of air-exposure stress followed by rehydration to reactivate them. Our objective was to elucidate the underlying mechanisms associated with drought tolerance, dormancy, and subsequent arousal based on transcriptomic analyses. The results indicated that the groups subjected to 5-, 15- and 30-day air-exposure stress treatments (DRY05, DRY15 and DRY30) exhibited a general down-regulation of metabolism-related pathways. These pathways included starch and sucrose metabolism, linoleic acid metabolism, glutathione metabolism and glycosaminoglycan degradation, compared with the control (CK). In addition, the weighted correlation network analysis (WGCNA) identified two critical pathways: toll-like receptor signaling pathway and adherens junction. The down-regulation of these pathways indicated a decrease in immune levels during dormancy in apple snails. This may further lead to the inhibition of apoptosis and a reduction in energy expenditure, thereby sustaining vital activities. The up-regulation of intercellular adhesion and immune-related pathways upon reawakening (RCY01) further substantiates the presence of this tolerance mechanism during dormancy in the apple snail. This study provides a reference for understanding the tolerance of apple snails to extreme environments, and provides a basic theory for apple snail biocontrol research.

Integrated control of leukocyte compartments as a feature of adaptive physiology

As a highly diverse and mobile organ, the immune system is uniquely equipped to participate in tissue responses in a tunable manner, depending on the number, type, and nature of cells deployed to the respective organ. Most acute organismal stressors that threaten survival-predation, infection, poisoning, and others-induce pronounced redistribution of immune cells across tissue compartments. Here, we review the current understanding of leukocyte compartmentalization under homeostatic and noxious conditions. We argue that leukocyte shuttling between compartments is a function of local tissue demands, which are linked to the organ's contribution to adaptive physiology at steady state and upon challenge. We highlight the neuroendocrine signals that relay and organize this trafficking behavior and outline mechanisms underlying the functional diversification of leukocyte responses. In this context, we discuss important areas of future inquiry and the implications of this scientific space for clinical medicine in the era of targeted immunomodulation.

Molecular mechanisms in liver repair and regeneration: from physiology to therapeutics

Liver repair and regeneration are crucial physiological responses to hepatic injury and are orchestrated through intricate cellular and molecular networks. This review systematically delineates advancements in the field, emphasizing the essential roles played by diverse liver cell types. Their coordinated actions, supported by complex crosstalk within the liver microenvironment, are pivotal to enhancing regenerative outcomes. Recent molecular investigations have elucidated key signaling pathways involved in liver injury and regeneration. Viewed through the lens of metabolic reprogramming, these pathways highlight how shifts in glucose, lipid, and amino acid metabolism support the cellular functions essential for liver repair and regeneration. An analysis of regenerative variability across pathological states reveals how disease conditions influence these dynamics, guiding the development of novel therapeutic strategies and advanced techniques to enhance liver repair and regeneration. Bridging laboratory findings with practical applications, recent clinical trials highlight the potential of optimizing liver regeneration strategies. These trials offer valuable insights into the effectiveness of novel therapies and underscore significant progress in translational research. In conclusion, this review intricately links molecular insights to therapeutic frontiers, systematically charting the trajectory from fundamental physiological mechanisms to innovative clinical applications in liver repair and regeneration.

The Effect of HBV Therapy on Glycemic Control in HBV-Infected Patients With Diabetes: A 90-day Multicenter Study

Patients with diabetes are at increased risk of HBV infection; however, the effects of HBV infection and anti-HBV therapy on the management of type 1 diabetes (T1D), type 2 diabetes (T2D), and latent autoimmune diabetes in adults (LADA) remain unclear. From 2016 to 2023, we recruited a multicenter cohort of 355 HBV-infected inpatients, including 136 with T1D, 140 with T2D, and 79 with LADA. The control group included 525 HBV-uninfected inpatients, comparing 171 with T1D, 204 with T2D and 150 with LADA. We employed propensity-score matching between cases and controls to minimize confounding effects. Hemoglobin A1c (HbA1c) was monitored at baseline and at months 1, 2, and 3. At baseline, median HbA1c was significantly higher in HBV-infected patients compared to their HBV-uninfected controls: T1D (10.4% vs. 7.5%, p < 0.01), T2D (9.6% vs. 8.6%, p = 0.01), and LADA (9.4% vs. 8.4%, p = 0.03). Baseline HbA1c levels were significantly lower in HBV-treated patients compared to those HBV-untreated patients, regardless of whether they were on antidiabetic therapy (p < 0.05). A 90-day follow-up consistently indicated lower HbA1c levels at baseline, as well as at months 1, 2, and 3 among HBV-treated patients with T1D, T2D, or LADA. Both univariate and multivariate analyses identified HBV therapy (OR = 0.44, p < 0.001) and antidiabetic treatment(OR = 0.51, p = 0.031) as protective factors for glycemic control in HBV-infected patients with diabetes. Poor glycemic control is found in HBV-infected patients with diabetes, but the intervention of anti-HBV therapy and antidiabetic treatment contributes to improved glycemic control in HBV-infected patients with T1D, T2D, or LADA.

The gut-liver axis links the associations between serum carotenoids and non-alcoholic fatty liver in a 7.8-year prospective study

Background

Many studies have shown that carotenoids are beneficial to non-alcoholic fatty liver disease (NAFLD). Therefore, we explored potential biomarkers of gut microbiota and fecal and serum metabolites linking the association between serum carotenoids and NAFLD in adults.

Methods

This 7.8-year prospective study included 2921 participants with serum carotenoids at baseline and determined NAFLD by ultrasonography (ULS-NAFLD) every 3 years. A total of 828 subjects additionally underwent magnetic resonance imaging to identify NAFLD (MRI-NAFLD). Gut microbiota was analyzed by 16S rRNA sequencing in 1,661 participants, and targeted metabolomics profiling in 893 feces and 896 serum samples was performed by ultrahigh-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) in the middle term.

Results

A total of 2,522 participants finished follow-up visits. Of these participants, 770, 301, 474, and 977 were categorized into NAFLD-free, improved, new-onset, and persistent NAFLD groups based on their ULS-NAFLD status changes, respectively, and 342/828 were MRI-verified NALFD. Longitudinal analyses showed an inverse association between carotenoids and NALFD risk/presence (P-trend <0.05). Multivariable-adjusted odds ratios (ORs)/hazard ratio (HR) [95% confidence intervals (CIs)] of NAFLD for quartile 4 (vs. quartile 1) of total carotenoids were 0.63 (0.50, 0.80) for incident ULS-NAFLD, 0.20 (0.15, 0.27) for persistent ULS-NAFLD, 1.53 (1.10, 2.12) for improved-NAFLD, and 0.58 (0.39, 0.87) for MRI-NAFLD. The biomarkers in the gut-liver axis significantly associated with both serum carotenoids and NAFLD included sixteen microbial genera mainly in Ruminococcaceae and Veillonellaceae family, nineteen fecal metabolites containing medium-chain fatty acids (MCFAs), bile acids, and carnitines, and sixteen serum metabolites belonging to organic acids and amino acids. The total carotenoids-related scores of significant microbial genera, fecal and serum metabolites mediated the carotenoids-NAFLD association by 8.72%, 12.30%, and 16.83% (all P<0.05) for persistent NAFLD and 9.46%, 8.74%, and 15.7% for incident-NAFLD, respectively.

Conclusions

Our study reveals a beneficial association of serum carotenoids and incident and persistent NAFLD. The identified gut-liver axis biomarkers provided mechanistic linkage for the epidemiological association.

Evaluation of Hepatic Glucose and Palmitic Acid Metabolism in Rodents on High-Fat Diet Using Deuterium Metabolic Imaging

BACKGROUND

One of the main features of several metabolic disorders is dysregulation of hepatic glucose and lipid metabolism. Deuterium metabolic imaging (DMI) allows for assessing the uptake and breakdown of 2H-labeled substrates, giving specific insight into nutrient processing in healthy and diseased organs. Thus, DMI could be a useful approach for analyzing the differences in liver metabolism of healthy and diseased subjects to gain a deeper understanding of the alterations related to metabolic disorders.

PURPOSE

Evaluating the feasibility of DMI as a tool for the assessment of metabolic differences in rodents with healthy and fatty livers (FLs).

STUDY TYPE

Animal Model.

POPULATION

18 male Sprague Dawley rats on standard (SD, n = 9, healthy) and high-fat diet (HFD, n = 9, FL disease).

FIELD STRENGTH/SEQUENCE

Phase-encoded 1D pulse-acquire sequence and anatomy co-registered phase-encoded 3D pulse-acquire chemical shift imaging for 2H at 9.4T.

ASSESSMENT

Localized and nonlocalized liver spectroscopy was applied at eight time points over 104 minutes post injection. The obtained spectra were preprocessed and quantified using jMRUI (v7.0) and the resulting amplitudes translated to absolute concentration (mM) according to the 2H natural abundance water peak.

STATISTICAL TESTS

Two-way repeated measures ANOVA were employed to assess between-group differences, with statistical significance at P < 0.05.

RESULTS

DMI measurements demonstrated no significant difference (P = 0.98) in the uptake of [6,6'-2H2]glucose between healthy and impaired animals (AUCSD = 1966.0 ± 151.5 mM - minutes vs. AUCHFD = 2027.0 ± 167.6 mM·minutes). In the diseased group, the intrahepatic uptake of palmitic acid d-31 was higher (AUCHFD = 57.4 ± 17.0 mM·minutes, AUCSD = 33.3 ± 10.5 mM·minutes), but without statistical significance owing to substantial in-group variation (P = 0.73).

DATA CONCLUSION

DMI revealed higher concentrations of palmitic acid in rats with FL disease and no difference in hepatic glucose concentration between healthy and impaired animals. Thus, DMI appears to be a useful tool for evaluating metabolism in rodents with FL disease.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 3.