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1.
Hum Reprod ; 38(11): 2128-2136, 2023 11 02.
Article in English | MEDLINE | ID: mdl-37671597

ABSTRACT

STUDY QUESTION: Can maternal serum levels of soluble programmed cell death-1 (sPD-1) and its ligand (sPD-L1) serve as biomarkers for missed miscarriage (MM)? SUMMARY ANSWER: Serum sPD-L1 levels are significantly decreased in MM patients and may serve as a potential predictive biomarker for miscarriage. WHAT IS KNOWN ALREADY: Programmed cell death-1 (PD-1) and its ligand (PD-L1) comprise important immune inhibitory checkpoint signaling to maintain pregnancy. Their soluble forms are detectable in human circulation and are associated with immunosuppression. STUDY DESIGN, SIZE, DURATION: Three independent cohorts attending tertiary referral hospitals were studied. The first (discovery) cohort was cross-sectional and included MM patients and healthy pregnant (HP) women matched on BMI. The second validation cohort contained MM patients and women with legally induced abortion (IA). The third prospective observational study recruited subjects requiring IVF treatment. PARTICIPANTS/MATERIALS, SETTING, METHODS: In the discovery cohort, we enrolled 108 MM patients and 115 HP women who had a full-term pregnancy at 6-14 weeks of gestation. In the validation cohort, we recruited 25 MM patients and 25 women with IA. Blood samples were collected at the first prenatal visit for HP women or on the day of dilatation and curettage surgery (D&C) for MM and IA subjects to determine serum sPD-1 and sPD-L1 levels. Placenta samples were harvested during the D&C within the validation cohort to measure gene and protein expression. The prospective cohort collected serial blood samples weekly from 75 volunteers with embryo transfer (ET) after IVF. MAIN RESULTS AND THE ROLE OF CHANCE: Circulating sPD-L1 levels were reduced by 50% in patients with MM (55.7 ± 16.04 pg/ml) compared to HP controls (106.7 ± 58.46 pg/ml, P < 0.001) and the difference remained significant after adjusting for maternal age and gestational age, whereas no significant differences in sPD-1 level were observed. Likewise, serum sPD-L1 was lower in MM patients than in IA subjects and accompanied by downregulated PD-L1-related gene expression levels in the placenta. In the IVF cohort, applying the changing rate of sPD-L1 level after ET achieved a predictive performance for miscarriage with receiver operating characteristics = 0.73 (95% CI: 0.57-0.88, P < 0.01). LIMITATIONS, REASONS FOR CAUTION: The study was mainly confined to East Asian pregnant women. Further large prospective pregnancy cohorts are required to validate the predictive performance of sPD-L1 on miscarriage. WIDER IMPLICATIONS OF THE FINDINGS: Reduced circulating sPD-L1 level and downregulated placental PD-L1 expression in miscarriage indicate that dysfunction in PD-L1 signals is a potential underlying mechanism for pregnancy loss. Our findings further extend the importance of the PD-L1 axis in pregnancy maintenance in early pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This study was financially supported by grants from the Subject Innovation Team of Shaanxi University of Chinese Medicine (2019-Y502), General Research Fund (14122021), and Key Laboratory of Model Animal Phenotyping and Basic Research in Metabolic Diseases (2018KSYS003). The authors declare that they have no competing interests to be disclosed. TRIAL REGISTRATION NUMBER: N/A.


Subject(s)
Abortion, Spontaneous , Animals , Pregnancy , Female , Humans , Prospective Studies , B7-H1 Antigen , Placenta , Cross-Sectional Studies , Ligands , Biomarkers , Apoptosis
2.
Cell Biol Toxicol ; 39(6): 3255-3267, 2023 12.
Article in English | MEDLINE | ID: mdl-37768392

ABSTRACT

Anthracycline antitumor agents, such as doxorubicin (DOX), are effective in the treatment of solid tumors and hematological malignancies, but anthracycline-induced cardiotoxicity (AIC) limits their application as chemotherapeutics. Dexrazoxane (DEX) has been adopted to prevent AIC. Using a chronic AIC mouse model, we demonstrated that DEX is insufficient to reverse DOX-induced cardiotoxicity. Although therapies targeting autophagy have been explored to prevent AIC, but whether novel autophagy inhibitors could alleviate or prevent AIC in clinically relevant models needs further investigation. Here, we show that genetic ablation of Atg7, a key regulator in the early phase of autophagy, protected mice against AIC. We further demonstrated that SAR405, a novel autophagy inhibitor, attenuated DOX-induced cytotoxicity. Intriguingly, the combination of DEX and SAR405 protected cells against DOX-induced cardiotoxicity in vivo. Using the cardiomyocyte cell lines AC16 and H9c2, we determined that autophagy was initiated during AIC. Our results suggest that inhibition of autophagy at its early phase with SAR405 combined with DEX represents an effective therapeutic strategy to prevent AIC.


Subject(s)
Cardiotoxicity , Doxorubicin , Mice , Animals , Cardiotoxicity/drug therapy , Cardiotoxicity/etiology , Cardiotoxicity/prevention & control , Doxorubicin/pharmacology , Antibiotics, Antineoplastic/toxicity , Antibiotics, Antineoplastic/metabolism , Myocytes, Cardiac/metabolism , Anthracyclines/metabolism , Anthracyclines/pharmacology , Anthracyclines/therapeutic use , Autophagy , Apoptosis , Oxidative Stress
3.
Rev Endocr Metab Disord ; 22(4): 1091-1109, 2021 12.
Article in English | MEDLINE | ID: mdl-34120289

ABSTRACT

Type 2 diabetes mellitus (T2DM) has become a global health problem with no cure. Despite lifestyle modifications and various pharmaceutical options, the achievement of stable and durable glucose control along with effective prevention of T2DM-related cardiovascular complications remains a challenging task in clinical management. With its selective high abundance in metabolic tissues (adipose tissue, liver, and pancreas), ß-Klotho is the essential component of fibroblast growth factor (FGF) receptor complexes. It is essential for high-affinity binding of endocrine FGF19 and FGF21 to evoke the signaling cascade actively involved in homeostatic maintenance of glucose metabolism and energy expenditure. In this Review, we discuss the biological function of ß-Klotho in the regulation of glucose metabolism and offer mechanistic insights into its involvement in the pathophysiology of T2DM. We review our current understanding of the endocrine axis comprised of ß-Klotho and FGFs (FGF19 and FGF21) and its regulatory effects on glucose metabolism under physiological and T2DM conditions. We also highlight advances in the development and preclinical validation of pharmacological compounds that target ß-Klotho and/or the ß-Klotho-FGFRs complex for the treatment of T2DM. Given the remarkable advances in this field, we also discuss outstanding research questions and the many challenges in the clinical development of ß-Klotho-based therapies.


Subject(s)
Diabetes Mellitus, Type 2 , Adipose Tissue/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Fibroblast Growth Factors/metabolism , Homeostasis , Humans , Liver/metabolism , Signal Transduction/physiology
4.
Rev Endocr Metab Disord ; 22(2): 407-420, 2021 06.
Article in English | MEDLINE | ID: mdl-33245468

ABSTRACT

Gestational diabetes mellitus (GDM) characterized by hyperglycemia during pregnancy is a risk factor for various maternal and fetal complications. The key pathophysiological mechanisms underlying its development have not been elucidated, largely due to the lack of a model that accurately simulates the major clinical and pathological features of human GDM. In this review, we discuss the refined criteria for an ideal animal model of GDM, focusing on the key clinical and pathophysiological characteristics of human GDM. We provide a comprehensive overview of different models and currently used species for GDM research. In general, insulin insufficiency consequent to pancreatic ß-cell death represents the current leading strategy to mimic human GDM-like hyperglycemia in animals. Nonetheless, these models have a limited capacity to mimic the natural history of GDM, the marked alteration in circulating estrogen/ progestogen, obesity and its related metabolic complications. We discuss emerging evidence of the increased susceptibility to GDM in rodents and large animals with genetic modifications in pregnancy-related hormones. An appraisal of current GDM models suggests that a combination strategy involving dietary stress, pregnancy-related hormones, insulin resistance and metabolic disorders might enable the development of better GDM models and expedite the translation of basic research findings to GDM treatment.


Subject(s)
Diabetes, Gestational , Hyperglycemia , Insulin Resistance , Insulin-Secreting Cells , Animals , Female , Humans , Insulin , Pregnancy
5.
BMC Endocr Disord ; 20(1): 158, 2020 Oct 22.
Article in English | MEDLINE | ID: mdl-33092580

ABSTRACT

BACKGROUND: A growing body of evidence supports neutrophils as having an active role in the development of diabetic kidney disease (DKD). However, the clinical relevance of neutrophils and DKD in autoimmune diabetes remains unknown. This study aimed to investigate the relationship between circulating neutrophils and DKD in autoimmune diabetes. METHODS: Patients with type 1 diabetes (T1D, n = 226) and latent autoimmune diabetes in adults (LADA, n = 79) were enrolled and stratified according to the urinary albumin to creatinine ratio (ACR). Circulating levels of white blood cells (WBCs), including neutrophils, were measured in a central laboratory, and the neutrophil-to-lymphocyte ratio (NLR) was calculated. The risk factors associated with DKD were analysed by logistic regression. RESULTS: In T1D and LADA patients, the peripheral neutrophil counts increased in parallel with DKD advancement. The neutrophil counts in the patients with macroalbuminuria were significantly higher than those in the patients with normoalbuminuria for each type of diabetes. Furthermore, neutrophil counts positively correlated with ACR in T1D. In addition, neutrophils were independently associated with DKD in T1D in the logistic regression analysis, when various well-known risk factors, including age, gender, disease duration, hypertension, dyslipidemia and smoking status, were adjusted. CONCLUSIONS: Neutrophil counts are closely associated with DKD in patients with autoimmune diabetes, suggesting that neutrophil-mediated inflammation may be involved in the pathogenesis of DKD in patients with autoimmune diabetes.


Subject(s)
Albuminuria/diagnosis , Biomarkers/analysis , Diabetes Mellitus, Type 1/complications , Diabetic Nephropathies/diagnosis , Neutrophils/pathology , Adult , Albuminuria/blood , Albuminuria/etiology , Diabetic Nephropathies/blood , Diabetic Nephropathies/etiology , Female , Follow-Up Studies , Humans , Male , Prognosis , Retrospective Studies , Risk Factors , Young Adult
6.
Faraday Discuss ; 216(0): 94-115, 2019 07 11.
Article in English | MEDLINE | ID: mdl-31016302

ABSTRACT

Here we present our theoretical investigations into the light reaction in the dimeric photosystem II (PSII) core complex. An effective model for excitation energy transfer (EET) and primary charge separation (CS) in the PSII core complex was developed, with model parameters constructed based on molecular dynamics (MD) simulation data. Compared to experimental results, we demonstrated that this model faithfully reproduces the absorption spectra of the RC and core light-harvesting complexes (CP43 and CP47) as well as the full EET dynamics among the chromophores in the PSII core complex. We then applied master equation simulations and network analysis to investigate detailed EET plus CS dynamics in the system, allowing us to identify key EET pathways and produce a coarse-grained cluster model for the light reaction in the dimeric PSII core complex. We show that non-equilibrium energy transfer channels play important roles in the efficient light harvesting process and that multiple EET pathways exist between subunits of PSII to ensure the robustness of light harvesting in the system. Furthermore, we revealed that inter-monomer energy transfer dominated by the coupling between the two CLA625 molecules enables efficient energy exchange between two CP47s in the dimeric PSII core complex, which leads to significant energy pooling in the CP47 domain during the light reaction. Our study provides a blueprint for the design of light harvesting in the PSII core and show that a structure-based approach using molecular dynamics simulations and quantum chemistry calculations can be effectively utilized to elucidate the dynamics of light harvesting in complex photosynthetic systems.

7.
Hepatology ; 64(2): 425-38, 2016 08.
Article in English | MEDLINE | ID: mdl-26926384

ABSTRACT

UNLABELLED: Among the 22 fibroblast growth factors (FGFs), FGF21 has now emerged as a key metabolic regulator. However, the mechanism whereby FGF21 mediates its metabolic actions per se remains largely unknown. Here, we show that FGF21 represses mammalian target of rapamycin complex 1 (mTORC1) and improves insulin sensitivity and glycogen storage in a hepatocyte-autonomous manner. Administration of FGF21 in mice inhibits mTORC1 in the liver, whereas FGF21-deficient mice display pronounced insulin-stimulated mTORC1 activation and exacerbated hepatic insulin resistance (IR). FGF21 inhibits insulin- or nutrient-stimulated activation of mTORC1 to enhance phosphorylation of Akt in HepG2 cells at both normal and IR condition. TSC1 deficiency abrogates FGF21-mediated inhibition of mTORC1 and augmentation of insulin signaling and glycogen synthesis. Strikingly, hepatic ßKlotho knockdown or hepatic hyperactivation of mTORC1/ribosomal protein S6 kinase 1 abrogates hepatic insulin-sensitizing and glycemic-control effects of FGF21 in diet-induced insulin-resistant mice. Moreover, FGF21 improves methionine- and choline-deficient diet-induced steatohepatitis. CONCLUSIONS: FGF21 acts as an inhibitor of mTORC1 to control hepatic insulin action and maintain glucose homeostasis, and mTORC1 inhibition by FGF21 has the therapeutic potential for treating IR and type 2 diabetes. (Hepatology 2016;64:425-438).


Subject(s)
Fibroblast Growth Factors/metabolism , Insulin Resistance , Liver/metabolism , Membrane Proteins/metabolism , Multiprotein Complexes/metabolism , TOR Serine-Threonine Kinases/metabolism , Animals , Diet, High-Fat , Glycogen/biosynthesis , Insulin/metabolism , Klotho Proteins , Male , Mechanistic Target of Rapamycin Complex 1 , Mice, Inbred C57BL , Mice, Knockout , Non-alcoholic Fatty Liver Disease/metabolism , Sucrose
8.
Hepatol Res ; 47(3): E104-E112, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27172177

ABSTRACT

AIM: This study aimed to evaluate the relationship between serum uric acid (SUA) level and non-alcoholic fatty liver disease (NAFLD) in non-obese adults. METHODS: A cross-sectional study was carried out among 4098 adults, including 1936 non-obese and 2162 obese individuals. An additional 93 non-obese adults with biopsy-proven NAFLD were also included. RESULTS: The overall prevalence of NAFLD was 39.51% in the study group, and 14.88% in non-obese adults. The NAFLD patients had significantly higher SUA levels than controls in both men and women. The non-obese group had a higher NAFLD risk with increased SUA levels than the obese group, with odd ratios (95% confidence interval) of 2.559 (1.870-3.503) and 1.692 (1.371-2.087), respectively. In 93 non-obese adults with biopsy-proven NAFLD, SUA levels were significantly higher in those with non-alcoholic steatohepatitis. The prevalence of non-alcoholic steatohepatitis and lobule inflammation tended to increase to 57.58% and 66.67% as the SUA level increased to the fourth quartile. Subjects with hyperuricemia had significantly higher NAFLD activity scores and more serious lobule inflammation than the normal group. CONCLUSION: Non-obese adults have higher NAFLD risk with increased SUA levels than obese individuals, and the inflammation progression of NAFLD is associated with increased SUA level in non-obese subjects.

9.
Circulation ; 131(21): 1861-71, 2015 May 26.
Article in English | MEDLINE | ID: mdl-25794851

ABSTRACT

BACKGROUND: Fibroblast growth factor 21 (FGF21) is a metabolic hormone with pleiotropic effects on glucose and lipid metabolism and insulin sensitivity. It acts as a key downstream target of both peroxisome proliferator-activated receptor α and γ, the agonists of which have been used for lipid lowering and insulin sensitization, respectively. However, the role of FGF21 in the cardiovascular system remains elusive. METHODS AND RESULTS: The roles of FGF21 in atherosclerosis were investigated by evaluating the impact of FGF21 deficiency and replenishment with recombinant FGF21 in apolipoprotein E(-/-) mice. FGF21 deficiency causes a marked exacerbation of atherosclerotic plaque formation and premature death in apolipoprotein E(-/-) mice, which is accompanied by hypoadiponectinemia and severe hypercholesterolemia. Replenishment of FGF21 protects against atherosclerosis in apolipoprotein E(-/-)mice via 2 independent mechanisms, inducing the adipocyte production of adiponectin, which in turn acts on the blood vessels to inhibit neointima formation and macrophage inflammation, and suppressing the hepatic expression of the transcription factor sterol regulatory element-binding protein-2, thereby leading to reduced cholesterol synthesis and attenuation of hypercholesterolemia. Chronic treatment with adiponectin partially reverses atherosclerosis without obvious effects on hypercholesterolemia in FGF21-deficient apolipoprotein E(-/-) mice. By contrast, the cholesterol-lowering effects of FGF21 are abrogated by hepatic expression of sterol regulatory element-binding protein-2. CONCLUSIONS: FGF21 protects against atherosclerosis via fine tuning the multiorgan crosstalk among liver, adipose tissue, and blood vessels.


Subject(s)
Adiponectin/physiology , Atherosclerosis/prevention & control , Fibroblast Growth Factors/therapeutic use , Sterol Regulatory Element Binding Protein 2/physiology , Adipocytes/drug effects , Adipocytes/metabolism , Adiponectin/biosynthesis , Adiponectin/deficiency , Adiponectin/genetics , Animals , Apolipoproteins E/deficiency , Atherosclerosis/drug therapy , Atherosclerosis/genetics , Atherosclerosis/metabolism , Cholesterol/biosynthesis , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Fibroblast Growth Factors/deficiency , Gene Expression Regulation/drug effects , Hyperlipoproteinemia Type II/complications , Hyperlipoproteinemia Type II/genetics , Hyperlipoproteinemia Type II/metabolism , Klotho Proteins , Liver/drug effects , Liver/metabolism , Membrane Proteins/deficiency , Membrane Proteins/drug effects , Membrane Proteins/physiology , Mice , Mice, Inbred C57BL , Mice, Knockout , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Receptor, Fibroblast Growth Factor, Type 2/drug effects , Receptor, Fibroblast Growth Factor, Type 2/physiology , Recombinant Proteins/therapeutic use , Signal Transduction/drug effects , Sterol Regulatory Element Binding Protein 2/biosynthesis , Sterol Regulatory Element Binding Protein 2/genetics
10.
J Hepatol ; 65(5): 988-997, 2016 11.
Article in English | MEDLINE | ID: mdl-27266617

ABSTRACT

BACKGROUND & AIMS: Inflammatory cell infiltration in the liver is a hallmark of non-alcoholic steatohepatitis (NASH). However, the pathological events which trigger the infiltration of inflammatory cells to mediate NASH pathogenesis remains poorly understood. This study aims to investigate the role of neutrophil-derived lipocalin 2 (LCN2) in mediating the transition from simple steatosis to NASH. METHODS: Animal models of NASH were induced by high fat high cholesterol (HFHC) diet and methionine- and choline-deficient (MCD) diet in LCN2 knockout mice and wild-type controls. RESULTS: Circulating levels of LCN2 and its hepatic expression were markedly increased in both murine models and human subjects with NASH, and these changes were associated with increased infiltration of neutrophils. In diet-induced NASH models, hepatic injury, necroinflammation and infiltration of neutrophils and macrophages were substantially attenuated by genetic depletion of LCN2. In contrast, chronic infusion of recombinant LCN2 exacerbated diet-induced liver injury, inflammation and macrophage accumulation in a neutrophil-dependent manner. Primary mouse neutrophils lacking LCN2 exhibited a defective migration capacity, which can be reversed by replenishment with recombinant LCN2. Mechanistically, LCN2 induced the expression of the chemokine (C-X-C motif) receptor 2 (CXCR2), thereby leading to activation of ERK1/2 and production of proinflammatory chemokines. LCN2-induced inflammation, infiltration of macrophages and liver injury was abrogated in CXCR2-deficient mice. CONCLUSIONS: These findings demonstrated that LCN2 acts as a central mediator to facilitate the crosstalk between neutrophils and hepatic macrophages via induction of the chemokine receptor CXCR2, thereby exacerbating steatohepatitis. LAY SUMMARY: Lipocalin-2 levels in blood and the liver were markedly increased in both mouse models and human subjects with NASH, and these changes were associated with increased infiltration of neutrophils in the liver. In diet-induced NASH models, hepatic injury, necroinflammation and infiltration of neutrophils and macrophages were substantially attenuated by genetic depletion of lipocalin-2, but was augmented by chronic infusion of recombinant lipocalin-2. Lipocalin-2 induced the expression of the chemokine receptor CXCR2, thereby leading to activation of the mitogen-activated protein (MAP) kinase ERK1/2 and production of proinflammatory chemokines. Lipocalin-2-induced inflammation, infiltration of macrophages and liver injury was abrogated in CXCR2-deficient mice.


Subject(s)
Non-alcoholic Fatty Liver Disease , Animals , Disease Models, Animal , Humans , Lipocalin-2 , Liver , Macrophages , Mice , Mice, Inbred C57BL , Neutrophils , Receptors, Interleukin-8B
11.
Clin Sci (Lond) ; 130(22): 2087-2100, 2016 11 01.
Article in English | MEDLINE | ID: mdl-27512097

ABSTRACT

Both atherosclerosis and obesity, an independent atherosclerotic risk factor, are associated with enhanced systemic inflammation. Obesity is also characterized by increased adipose tissue inflammation. However, the molecular mechanism underlying the accelerated atherosclerosis in obesity remains unclear. In obesity, activation of c-Jun N-terminal kinase (JNK) contributes to adipose tissue inflammation. The present study investigated whether the suppression of fat inflammation through adipose-specific JNK inactivation could protect against atherosclerosis in mice. ApoE-/- mice were cross-bred with transgenic mice with adipose-specific expression of a dominant negative form of JNK (dnJNK) to generate apoE-/-/dnJNK (ADJ) mice. ADJ mice treated with a high-fat-high-cholesterol diet exhibited significant attenuations of visceral fat and systemic inflammation without changes in lipid or glucose metabolism, and were protected against atherosclerosis, when compared with apoE-/- mice. Lean apoE-/- mice that received transplantation of visceral fat from obese wild-type donor mice for 4 weeks showed exacerbated systemic inflammation and atherosclerotic plaque formation. Conversely, apoE-/- recipients carrying a visceral fat graft from obese dnJNK donors were protected against enhanced systemic inflammation and atherogenesis. The beneficial effects of adipose-specific JNK inactivation on atherogenesis in apoE-/- recipients were significantly compromised by continuous infusion of recombinant adipocyte-fatty acid-binding protein (A-FABP), previously shown to interact with JNK via a positive feedback loop to modulate inflammatory responses. Together these data suggested that enhanced atherosclerosis in obesity can be attributed, at least in part, to a distant cross-talk between visceral fat and the vasculature, mediated by the release of proinflammatory cytokines, such as A-FABP, from the inflamed visceral adipose tissue with JNK activation.


Subject(s)
Adipose Tissue/enzymology , Apolipoproteins E/deficiency , Atherosclerosis/enzymology , MAP Kinase Kinase 4/immunology , Obesity/complications , Adipose Tissue/immunology , Animals , Apolipoproteins E/genetics , Atherosclerosis/etiology , Atherosclerosis/genetics , Atherosclerosis/immunology , Humans , MAP Kinase Kinase 4/genetics , Male , Mice , Mice, Knockout , Obesity/genetics , Obesity/immunology
12.
Clin Exp Pharmacol Physiol ; 43(1): 13-21, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26444279

ABSTRACT

An imbalance between neutrophil elastase (NE) and its inhibitor α1-antitrypsin (A1 AT) is known to contribute to the development of obesity-related inflammation. This study aimed to investigate the role of the NE-A1 AT system in the histological progression of non-alcoholic fatty liver disease (NAFLD), and to evaluate the ability of it to predict nonalcoholic steatohepatitis (NASH). A total of 252 adults (NAFLD group, n = 202; healthy group, n = 50) were recruited. Clinical biochemical characteristics, NE and A1 AT concentrations were measured in all subjects. Among the NAFLD group, 86 patients had previously undergone liver biopsy and information on histological characteristics was consequently available. The area under the receiver operating characteristic curve (AUC) was used to determine the predictive accuracy of the NE-A1 AT system for NASH. NAFLD patients had an elevated serum NE concentration and a reduced A1 AT level with consequent NE/A1 AT imbalance. NE increased in the early stage of steatosis, preceding the decline in A1 AT, dating from the onset of NASH (NAS 3-4), and subsequently NE/A1 AT increased in the presence of NASH. Nonetheless, this increase began to resolve as the disease state progressed to advanced fibrosis. A1 AT had a sensitivity (SEN) of 83.8% and a specificity (SP) of 83.3% with the optimal cut-off of -1459.43, NE/A1 AT had a SEN of 88.8% and a SP of 83.3% with cut-off of 0.363 to predict NASH. An increased NE: A1 AT ratio is closely associated with liver Inflammation in patients with NASH and could serve as a novel marker to predict NASH in humans.


Subject(s)
Leukocyte Elastase/blood , Liver/pathology , Non-alcoholic Fatty Liver Disease/blood , alpha 1-Antitrypsin/blood , Adult , Blood Glucose/metabolism , Case-Control Studies , Disease Progression , Female , Fibrosis , Humans , Inflammation/blood , Insulin Resistance , Liver/enzymology , Male , Neutrophils/cytology , Non-alcoholic Fatty Liver Disease/enzymology , Non-alcoholic Fatty Liver Disease/immunology , Non-alcoholic Fatty Liver Disease/pathology
13.
Hepatology ; 60(3): 977-89, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24590984

ABSTRACT

UNLABELLED: Acetaminophen (APAP) overdose is a leading cause of drug-induced hepatotoxicity and acute liver failure worldwide, but its pathophysiology remains incompletely understood. Fibroblast growth factor 21 (FGF21) is a hepatocyte-secreted hormone with pleiotropic effects on glucose and lipid metabolism. This study aimed to investigate the pathophysiological role of FGF21 in APAP-induced hepatotoxicity in mice. In response to APAP overdose, both hepatic expression and circulating levels of FGF21 in mice were dramatically increased as early as 3 hours, prior to elevations of the liver injury markers alanine aminotransferase (ALT) and aspartate aminotransferase (AST). APAP overdose-induced liver damage and mortality in FGF21 knockout (KO) mice were markedly aggravated, which was accompanied by increased oxidative stress and impaired antioxidant capacities as compared to wild-type (WT) littermates. By contrast, replenishment of recombinant FGF21 largely reversed APAP-induced hepatic oxidative stress and liver injury in FGF21 KO mice. Mechanistically, FGF21 induced hepatic expression of peroxisome proliferator-activated receptor coactivator protein-1α (PGC-1α), thereby increasing the nuclear abundance of nuclear factor erythroid 2-related factor 2 (Nrf2) and subsequent up-regulation of several antioxidant genes. The beneficial effects of recombinant FGF21 on up-regulation of Nrf2 and antioxidant genes and alleviation of APAP-induced oxidative stress and liver injury were largely abolished by adenovirus-mediated knockdown of hepatic PGC-1α expression, whereas overexpression of PGC-1α was sufficient to counteract the increased susceptibility of FGF21 KO mice to APAP-induced hepatotoxicity. CONCLUSION: The marked elevation of FGF21 by APAP overdose may represent a compensatory mechanism to protect against the drug-induced hepatotoxicity, by enhancing PGC-1α/Nrf2-mediated antioxidant capacity in the liver.


Subject(s)
Acetaminophen/toxicity , Analgesics, Non-Narcotic/toxicity , Antioxidants/physiology , Chemical and Drug Induced Liver Injury/prevention & control , Fibroblast Growth Factors/therapeutic use , Transcription Factors/physiology , Animals , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/mortality , Drug Synergism , Fibroblast Growth Factors/blood , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , NF-E2-Related Factor 2/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Reactive Oxygen Species/metabolism
14.
Clin Exp Pharmacol Physiol ; 41(7): 482-8, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24739055

ABSTRACT

The aim of the present study was to investigate Toll-like receptor-4 (TLR4) signalling at different stages of non-alcoholic fatty liver disease (NAFLD) induced by a high-fat, high-fructose (HFHFr) diet in mice. Both TLR4 wild-type (WT) and mutant (TLR4(mut) ) mice were fed either standard chow (SC) or the HFHFr diet for different periods of time from 4 to 16 weeks. Pathological characteristics and function of the liver were assessed. Simple steatosis, steatohepatitis and hepatic fibrosis occurred sequentially in Week 4, 8 and 16 in WT mice fed with the HFHFr. Expression of TLR4, myeloid differentiation factor 88 (MyD88), interferon regulatory factor (IRF) 3 and IRF7 started to increase at Week 4, peaked at Week 8 and then declined to basal levels at Week 16. This pattern was consistent with changes in inflammation in the liver revealed by haematoxylin and eosin staining. However, lipid accumulation, inflammation and fibrosis in livers of TLR4(mut) mice fed the HFHFr diet were significantly alleviated. In addition, the expression of activin A in WT mice fed the HFHFr diet increased at Week 16. The data suggest that TLR4 signalling mediates non-alcoholic steatohepatitis before fibrosis and that activin A is subsequently involved in NAFLD.


Subject(s)
Dietary Fats/toxicity , Dietary Sucrose/toxicity , Fructose/toxicity , Non-alcoholic Fatty Liver Disease/chemically induced , Toll-Like Receptor 4/metabolism , Activins/genetics , Activins/metabolism , Animals , Dietary Fats/administration & dosage , Dietary Sucrose/administration & dosage , Fructose/administration & dosage , Gene Expression Regulation/drug effects , Gene Expression Regulation/physiology , Interferon Regulatory Factor-3/genetics , Interferon Regulatory Factor-3/metabolism , Interferon Regulatory Factor-7/genetics , Interferon Regulatory Factor-7/metabolism , Mice , Mice, Knockout , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Signal Transduction , Toll-Like Receptor 4/genetics , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism
15.
J Ethnopharmacol ; 335: 118650, 2024 Dec 05.
Article in English | MEDLINE | ID: mdl-39094755

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Linggui-Zhugan (LGZG) comprises four herbs and is a classic formula in traditional Chinese medicine. There is strong clinical evidence of its pleiotropic effects in the prevention of diabetes and its related complications. Although several classes of drugs are currently available for clinical management of diabetic kidney disease (DKD), tight glycemic and/or hypertension control may not prevent disease progression. This study evaluated the therapeutic effect of the ethnopharmacological agent LGZG on DKD. AIM OF THE STUDY: This study aimed to investigate the effects of LGZG formula with standard quality control on experimental DKD and its related metabolic disorders in animal model. Meanwhile, the present study aimed to investigate regulatory effects of LGZG on renal proteinase 3 (PR3) to reveal mechanisms underlying renoprotective benefits of LGZG. MATERIALS AND METHODS: LGZG decoction was fingerprinted by high-performance liquid chromatography for quality control. An experimental model of DKD was induced in C57 BL/6J mice by a combination of high-fat diet feeding, uninephrectomy, and intraperitoneal injection of streptozocin. The LGZG decoction was administrated by daily oral gavage. RESULTS: Treatment with LGZG formula significantly attenuated DKD-like traits (including severe albuminuria, mesangial matrix expansion, and podocyte loss) and metabolic dysfunction (disordered body composition and dyslipidemia) in mice. RNA sequencing data revealed a close association of LGZG treatment with marked modulation of signaling pathways related to podocyte injury and cell apoptosis. Mechanistically, LGZG suppressed the DKD-triggered increase in renal PR3 and podocyte apoptosis. In-vitro incubation of mouse immortalized podocytes with LGZG-medicated serum attenuated PR3-mediated apoptosis. CONCLUSION: Our data demonstrated that the LGZG formula protected against DKD in mice and was closely associated with its inhibitory effects on PR3-mediated podocyte apoptosis.


Subject(s)
Apoptosis , Diabetic Nephropathies , Drugs, Chinese Herbal , Mice, Inbred C57BL , Podocytes , Animals , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/prevention & control , Diabetic Nephropathies/pathology , Podocytes/drug effects , Podocytes/pathology , Apoptosis/drug effects , Drugs, Chinese Herbal/pharmacology , Male , Mice , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Experimental/complications
16.
Research (Wash D C) ; 7: 0382, 2024.
Article in English | MEDLINE | ID: mdl-38812532

ABSTRACT

Metabolic dysfunction-associated steatohepatitis (MASH) is the progressive form of metabolic dysfunction-associated steatotic liver disease (MASLD), and closely associated with a high risk of liver-related morbidity and mortality. Although enhanced neutrophil infiltration of the liver is a histological hallmark of MASH, the morphological pattern of hepatic neutrophils and their relevance to the definition of MASH remain unknown. This clinicopathological study aimed to determine the association of neutrophilic crown-like structures (CLSs) in liver biopsies and evaluate their relevance to the histological diagnosis of MASH. A total of 483 morbidly obese adults who underwent bariatric surgery were recruited. Neutrophilic CLSs in liver biopsies were detected by immunohistochemistry for neutrophil elastase and proteinase 3. All participants were classified into 4 histological subgroups: no MASLD (118, 24.4%), MASLD (76, 15.7%), borderline MASH (185, 38.3%), and definite MASH (104, 21.5%). In the discovery cohort (n = 379), the frequency of neutrophilic CLSs increased in line with the severity of liver disease. The number of neutrophilic CLSs was positively correlated with established histological characteristics of MASH. At a cutoff value of <0.3 per 20× microscopic field, the number of neutrophilic CLSs yielded a robust diagnostic accuracy to discriminate no MASLD and MASLD from borderline MASH and definite MASH; a cutoff at >1.3 per 20× microscopic field exhibited a statistically significant accuracy to distinguish definite MASH from other groups (no MASLD, MASLD, and borderline MASH). The significance of neutrophilic CLSs in identifying borderline MASH and definite MASH was confirmed in an external validation cohort (n = 104). The frequency of neutrophilic CLSs was significantly higher than that of macrophagic CLSs. In conclusion, neutrophilic CLSs in the liver represent a typical histological characteristic of MASH and may serve as a promising indicator to improve the diagnostic accuracy of MASH during histological assessment of liver biopsies.

17.
Eur J Pharmacol ; 963: 176275, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38113968

ABSTRACT

Reperfusion therapy is currently the most effective treatment for acute ischemic stroke, but often results in secondary brain injury. Adipocyte fatty acid-binding protein (A-FABP, FABP4, or aP2) was shown to critically mediate cerebral ischemia/reperfusion (I/R) injury by exacerbating blood-brain barrier (BBB) disruption. However, no A-FABP inhibitors have been approved for clinical use due to safety issues. Here, we identified the therapeutic effect of levofloxacin, a widely used antibiotic displaying A-FABP inhibitory activity in vitro, on cerebral I/R injury and determined its target specificity and action mechanism in vivo. Using molecular docking and site-directed mutagenesis, we showed that levofloxacin inhibited A-FABP activity through interacting with the amino acid residue Asp76, Gln95, Arg126 of A-FABP. Accordingly, levofloxacin significantly inhibited A-FABP-induced JNK phosphorylation and expressions of proinflammatory factors and matrix metalloproteinase 9 (MMP-9) in mouse primary macrophages. In wild-type mice with transient middle cerebral artery occlusion, levofloxacin substantially mitigated BBB disruption and neuroinflammation, leading to reduced cerebral infarction, alleviated neurological outcomes, and improved survival. Mechanistically, levofloxacin decreased MMP-9 expression and activity, and thus reduced degradation of extracellular matrix and endothelial tight junction proteins. Importantly, the BBB- and neuro-protective effects of levofloxacin were abolished in A-FABP or MMP-9 knockout mice, suggesting that the therapeutic effects of levofloxacin highly depended on specific targeting of the A-FABP-MMP-9 axis. Overall, our study demonstrates that levofloxacin alleviates A-FABP-induced BBB disruption and neural tissue injury following cerebral I/R, and unveils its therapeutic potential for the treatment of ischemic stroke.


Subject(s)
Brain Ischemia , Ischemic Stroke , Reperfusion Injury , Animals , Mice , Rats , Blood-Brain Barrier/metabolism , Brain Ischemia/complications , Brain Ischemia/drug therapy , Infarction, Middle Cerebral Artery/metabolism , Ischemic Stroke/drug therapy , Levofloxacin/pharmacology , Levofloxacin/therapeutic use , Matrix Metalloproteinase 9/metabolism , Molecular Docking Simulation , Rats, Sprague-Dawley , Reperfusion , Reperfusion Injury/metabolism , Fatty Acid-Binding Proteins/drug effects , Fatty Acid-Binding Proteins/metabolism
18.
Gut ; 61(7): 1058-67, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22253482

ABSTRACT

BACKGROUND: Non-alcoholic fatty liver disease is an obesity-related chronic liver disorder ranging from simple steatosis to non-alcoholic steatohepatitis (NASH), which may progress to liver fibrosis and cirrhosis. OBJECTIVE: Tto investigate the role of Toll-like receptor (TLR) 4 in mediating the transition from steatosis to inflammation. METHODS: ApoE(-/-)/TLR4(mut) mice and ApoE(-/-)/TLR4 wild-type mice (ApoE(-/-)/TLR4-WT) were generated by cross-breeding an ApoE-deficient (ApoE(-/-)) strain with TLR4-mutant (TLR4(mut)) mice, which were fed with high-fat, high-cholesterol (HFHC) diet to induce obesity. RESULTS: ApoE(-/-)/TLR4-WT mice fed with an HFHC diet for 12 weeks developed typical pathological features of NASH, which is associated with obesity and the metabolic syndrome. By contrast, ApoE(-/-)/TLR4(mut) mice lacking functional TLR4 were resistant to HFHC diet-induced liver inflammation and injury and were less susceptible to the diet-induced production of reactive oxygen species (ROS) and proinflammatory cytokines. In ApoE(-/-)/TLR4-WT mice, X-box binding protein-1 (XBP-1), a transcription factor involved in the unfolded protein responses, was activated in the liver by an HFHC diet, whereas XBP-1 activation was abrogated in ApoE(-/-)/TLR4(mut) mice. In primary rat Kupffer cells, endotoxin induced XBP-1 activation through ROS production, whereas siRNA-mediated knockdown of XBP-1 expression resulted in a marked attenuation in endotoxin-evoked NF-κB activation and cytokine production. Furthermore, adenovirus-mediated expression of dominant negative XBP-1 led to a significant attenuation in HFHC diet-induced liver inflammation and injury in mice. CONCLUSIONS: These findings support the key role of TLR4 in Kupffer cells in mediating the progression of simple steatosis to NASH, by inducing ROS-dependent activation of XBP-1.


Subject(s)
DNA-Binding Proteins/metabolism , Dietary Fats/metabolism , Fatty Liver/metabolism , Kupffer Cells/metabolism , NF-kappa B/metabolism , Obesity/metabolism , Toll-Like Receptor 4/metabolism , Toll-Like Receptors/metabolism , Transcription Factors/metabolism , Animals , Mice , Mice, Inbred C57BL , Mice, Knockout , Non-alcoholic Fatty Liver Disease , Regulatory Factor X Transcription Factors , Reverse Transcriptase Polymerase Chain Reaction , X-Box Binding Protein 1
19.
Free Radic Biol Med ; 209(Pt 1): 9-17, 2023 11 20.
Article in English | MEDLINE | ID: mdl-37806596

ABSTRACT

BACKGROUND: Evidence from longitudinal studies is crucial to enhance our understanding of the role of metabolites in the progression of gestational diabetes mellitus (GDM). Herein, a longitudinal untargeted metabolomic study was conducted to reveal the metabolomic profiles and biomarkers associated with the progression of GDM, and characterize the changing patterns of metabolites. METHODS: We collected serum samples at three trimesters from 30 patients with GDM and 30 healthy Chinese pregnant women with pre-pregnancy BMI, age, and parity matched, and untargeted metabolomic analysis was performed, followed by machine learning approaches that integrated bootstrap and LASSO. Cluster analysis was conducted to elucidate the patterns of metabolite changes. Pathway analyses were conducted to gain insights into the underlying pathways involved. RESULTS: A total of 32 metabolites, mainly belonging to amino acid and its derivatives, were significantly associated with GDM across three trimesters, and were clustered into three distinct patterns. Metabolites belonging to phosphatidylcholines, lysophosphatidylcholines, lysophosphatidic acids, and lysophosphatidylethanolamines were consistently upregulated, and 2,3-Dihydroxypropyl dihydrogen phosphate was downregulated in GDM group. Amino acid-related, glycerophospholipid, and vitamin B6 metabolism were enriched in multiple trimesters. The levels of allantoic acid, which was positively correlated with blood glucose, was consistently higher in GDM patients and exhibited good discriminatory ability for GDM in the early and mid-pregnancy. CONCLUSION: We identified and characterized distinct patterns of metabolites associated with GDM throughout pregnancy, and found that allantoic acid was a potential biomarker for early diagnosis of GDM.


Subject(s)
Diabetes, Gestational , Pregnancy , Humans , Female , Diabetes, Gestational/diagnosis , Diabetes, Gestational/metabolism , Amino Acids/metabolism , Metabolomics , Biomarkers , Machine Learning
20.
Gut Microbes ; 15(1): 2154552, 2023.
Article in English | MEDLINE | ID: mdl-36550785

ABSTRACT

Gestational diabetes mellitus (GDM) is characterized by the development of hyperglycemia and insulin resistance during the second or third trimester of pregnancy, associated with considerable risks to both the mother and developing fetus. Although emerging evidence suggests an association between the altered gut microbiota and GDM, remarkably little is known about the microbial and metabolic mechanisms that link the dysbiosis of the gut microbiota to the development of GDM. In this study, a metagenome-wide association study and serum metabolomics profiling were performed in a cohort of pregnant women with GDM and pregnant women with normal glucose tolerance (NGT). We identified gut microbial alterations associated with GDM and linked to the changes in circulating metabolites. Blood metabolite profiles revealed that GDM patients exhibited a marked increase in 2-hydroxybutyric acid and L-alpha-aminobutyric acid, but a decrease in methionine sulfoxide, allantoin, and dopamine and dopaminergic synapse, when compared with those in NGT controls. Short-chain fatty acid-producing genera, including Faecalibacterium, Prevotella, and Streptococcus, and species Bacteroides coprophilus, Eubacterium siraeum, Faecalibacterium prausnitzii, Prevotella copri, and Prevotella stercorea, were significantly reduced in GDM patients relative to those in NGT controls. Bacterial co-occurrence network analysis revealed that pro-inflammatory bacteria were over-represented as the core species in GDM patients. These microbial and metabolic signatures are closely associated with clinical parameters of glucose metabolism in GDM patients and NGT controls. In conclusion, we identified circulating dopamine insufficiency, imbalanced production of SCFAs, and excessive metabolic inflammation as gut microbiota-driven multiple parallel hits linked to GDM development. This work might explain in part the mechanistic link between altered gut microbiota and GDM pathogenesis, and suggest that gut microbiota may serve as a promising target to intervene in GDM.


Subject(s)
Diabetes, Gestational , Gastrointestinal Microbiome , Humans , Pregnancy , Female , Diabetes, Gestational/microbiology , Blood Glucose/metabolism , Metagenome , Dopamine/analysis , Metabolomics , Bacteria/genetics , Bacteria/metabolism
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