The aim of this study was to investigate the improvement effect of Wenpi Pills(WPP) on non-alcoholic fatty liver disease(NAFLD). The experiment was divided into two parts, using C57BL/6 mouse models induced by a high-fat diet(HFD) and a methionine and choline deficiency diet(MCD). The HFD-induced experiment lasted for 16 weeks, while the MCD-induced experiment lasted for 6 weeks. Mice in both parts were divided into four groups: control group, model group, low-dose WPP group(3.875 g·kg~(-1), WPP＿L), and high-dose WPP group(15.5 g·kg~(-1), WPP＿H). After sample collection from the HFD-induced mice, lipid content in the serum and liver, liver function indexes in the serum, and hepatic pathology were examined. Real-time fluorescent quantitative reverse transcription PCR(qRT-PCR) was used to detect the expression of lipid-related genes. After sample collection from the MCD-induced mice, serum liver function indexes and inflammatory factors were measured, and hepatic pathology and lipid changes were analyzed by hematoxylin-eosin(HE) staining and widely targeted lipidomic profiling, respectively. The results from the HFD-induced experiment showed that, compared with the HFD group, WPP administration significantly reduced the levels of aspartate aminotransferase(AST), alanine aminotransferase(ALT), triglyceride(TG), and total cholesterol(TC) in the serum, with the WPP＿H group showing the most significant improvement. HE staining results indicated that, compared with the HFD group, WPP treatment improved the morphology of white adipocytes, reducing their size, and alleviated hepatic steatosis and lipid droplet accumulation. The qRT-PCR results suggested that WPP might increase the mRNA expression of liver cholesterol-converting genes, such as liver X receptor α(LXRα) and cytochrome P450 family 27 subfamily A member 1(CYP27A1), as well as lipid consumption genes like peroxisome proliferator-activated receptor α(PPARα) and adenosine mono-phosphate-activated protein kinase(AMPK). Meanwhile, WPP decreased the mRNA expression of lipid synthesis genes, including fatty acid synthetase(FAS), stearoyl-CoA desaturase 1(SCD1), and sterol regulatory element-binding protein 1c(SREBP-1c), thereby reducing liver lipid accumulation. The results from the MCD-induced experiment showed that, compared with the MCD group, WPP administration reduced the levels of ALT, AST, and inflammatory factors in the serum, thereby alleviating liver injury and the inflammatory response. HE staining of liver tissue indicated that WPP effectively improved hepatic steatosis. Non-targeted lipidomics analysis showed that WPP improved lipid metabolism disorders in the liver, mainly by affecting the metabolism of TG and cholesterol esters. In conclusion, WPP can improve hepatic lipid accumulation in NAFLD mice induced by both HFD and MCD. This beneficial effect is primarily achieved by alleviating liver injury and inflammation, as well as regulating lipid metabolism.
Animals ; Non-alcoholic Fatty Liver Disease/genetics* ; Lipid Metabolism/drug effects* ; Mice ; Mice, Inbred C57BL ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Diet, High-Fat/adverse effects* ; Liver/drug effects* ; Humans ; Disease Models, Animal ; Methionine

This study aims to investigate the in vitro mechanisms underlying the beneficial effects of puerarin on hepatic insulin resistance(IR) based on the carbohydrate response element-binding protein(ChREBP)/peroxisome proliferator-activated receptor(PPAR)α/PPARγ axis involved in glucose and lipid metabolism. An IR-HepG2 cell model was established by treating cells with dexamethasone for 48 h, and the cells were then treated with 10, 20, and 40 μmol·L~(-1) puerarin for 24 h. Glucose levels and output in the extracellular fluid were measured by the glucose oxidase method, while cell viability was assessed by the cell counting kit-8(CCK-8) assay. The adenosine triphosphate(ATP) content and glycogen synthesis were evaluated through chemiluminescence and periodic acid-Schiff staining, respectively. Western blot was employed to quantify the protein levels of forkhead box protein O1(FoxO1), phosphorylated forkhead box protein O1 [p-FoxO1(Ser256)], glucagon, phosphofructokinase, liver type(PFKL), pyruvate kinase L-R(PKLR), pyruvate dehydrogenase complex 1(PDHA1), insulin receptor substrate 2(IRS2), phosphatidylinositol 3-kinase p85(PI3KR1), phosphorylated protein kinase B [p-Akt(Thr308)], glycogen synthase(GYS), glycogen phosphorylase, liver type(PYGL), adiponectin(ADPN), ChREBP, PPARα, and PPARγ. Additionally, the protein levels of acetyl-CoA carboxylase 1(ACC1), phosphorylated ATP citrate lyase [p-ACLY(Ser455)], sterol regulatory element binding protein 1c(SREBP-1c), peroxisome proliferator-activated receptor gamma coactivator 1α(PGC1α), carnitine palmitoyltransferase 1α(CPT1α), and glucagon receptor(GCGR) were also determined. Immunofluorescence was employed to visualize the expression and nuclear location of ChREBP/PPARα/PPARγ. Furthermore, quantitative PCR with the antagonists GW6471 and GW9662 was employed to assess Pparα, Pparγ, and Chrebp. The findings indicated that puerarin effectively reduced both the glucose level and glucose output in the extracellular fluid of IR-HepG2 cells without obvious effect on the cell viability, and it increased intracellular glycogen and ATP levels. Puerarin down-regulated the protein levels of FoxO1 and glucagon while up-regulating the protein levels of p-FoxO1(Ser256), PFKL, PKLR, PDHA1, IRS2, PI3KR1, p-Akt(Thr308), GYS, PYGL, ADPN, ACC1, SREBP-1c, p-ACLY(Ser455), PGC1α, CPT1α, and GCGR in IR-HepG2 cells. Furthermore, puerarin up-regulated both the mRNA and protein levels of ChREBP, PPARα, and PPARγ and promoted the translocation into the nucleus. GW6471 was observed to down-regulate the expression of Pparα while up-regulating the expression of Chrebp and Pparγ. GW9662 down-regulated the expression of Pparγ while up-regulating the expression of Pparα, with no significant effect on Chrebp. In summary, puerarin activated the hepatic ChREBP/PPARα/PPARγ axis, thereby coordinating the glucose and lipid metabolism, promoting the conversion of glucose to lipids to exert the blood glucose-lowering effect.
Isoflavones/pharmacology* ; Humans ; PPAR gamma/genetics* ; Hep G2 Cells ; Glucose/metabolism* ; Lipid Metabolism/drug effects* ; PPAR alpha/genetics* ; Liver/drug effects* ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics* ; Insulin Resistance

Idiopathic pulmonary fibrosis(IPF) is a chronic progressive interstitial lung disease characterized by a complex pathogenesis and limited treatment options. Although studies have indicated that lipid metabolism dysregulation is associated with the progression of IPF, the core regulatory mechanisms remain unclear. By integrating RNA sequencing data from the GEO database, we identified four key genes related to lipid metabolism: peroxisome proliferator-activated receptor gamma(PPARG), secreted phosphoprotein 1(SPP1), caspase 3(CASP3), and platelet endothelial cell adhesion molecule 1(PECAM1). Further validation using single-cell RNA sequencing revealed the cell-specific expression patterns of these genes. The results found that PPARG was significantly downregulated in alveolar macrophages while SPP1 was significantly upregulated. Mechanistic studies indicated that PPARG negatively regulated SPP1 expression, and the interaction between SPP1 and cluster of differentiation 44(CD44) activated intercellular signaling pathways that promoted fibrosis. Through network pharmacology and molecular docking, it was predicted that the bioactive components of the traditional Chinese medicine formula, namely Buyang Huanwu Decoction may target PPARG to modulate lipid metabolism pathways. In a bleomycin-induced rat model with IPF, this paper randomly divided the rats into six groups(control, group, model group, pirfenidone group, and low, middle, and high-dose groups of Buyang Huanwu Decoction). The results demonstrated that Buyang Huanwu Decoction treatment significantly improved tissue pathological damage, reduced collagen deposition, and alleviated lipid metabolism dysregulation. Western blot analysis confirmed that Buyang Huanwu Decoction mediated the upregulation of PPARG and inhibited the activation of the SPP1/CD44 pathway. The multi-omics study elucidated the role of the PPARG/SPP1/CD44 pathway as a key regulatory factor in lipid metabolism in IPF, providing evidence that Buyang Huanwu Decoction exerted its antifibrotic effects through this novel mechanism and thus offering new insights into the therapeutic prospects for IPF.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Signal Transduction/drug effects* ; PPAR gamma/genetics* ; Humans ; Osteopontin/genetics* ; Lipid Metabolism/drug effects* ; Idiopathic Pulmonary Fibrosis/genetics* ; Hyaluronan Receptors/genetics* ; Rats ; Male ; Rats, Sprague-Dawley ; Molecular Docking Simulation

The gut microbiota regulates intestinal nutrient absorption, participates in modulating host glucolipid metabolism, and contributes to ameliorating glucolipid metabolism disorder. Dysbiosis of the gut microbiota can compromise the integrity of the intestinal mucosal barrier, induce inflammatory responses, and exacerbate insulin resistance and abnormal lipid metabolism in the host. Dangua Humai Oral Liquid, a hospital-developed formulation for regulating glucolipid metabolism, has been granted a national invention patent and demonstrates significant clinical efficacy. This study aimed to investigate the effects of Dangua Humai Oral Liquid on gut microbiota and the intestinal mucosal barrier in a mouse model with glucolipid metabolism disorder. A glucolipid metabolism disorder model was established by feeding mice a high-glucose and high-fat diet. The mice were divided into a normal group, a model group, and a treatment group, with eight mice in each group. The treatment group received a daily gavage of Dangua Humai Oral Liquid(20 g·kg~(-1)), while the normal group and model group were given an equivalent volume of sterile water. After 15 weeks of intervention, glucolipid metabolism, intestinal mucosal barrier function, and inflammatory responses were evaluated. Metagenomics and untargeted metabolomics were employed to analyze changes in gut microbiota and associated metabolic pathways. Significant differences were observed between the indicators of the normal group and the model group. Compared with the model group, the treatment group exhibited marked improvements in glucolipid metabolism disorder, alleviated pathological damage in the liver and small intestine tissue, elevated expression of recombinant claudin 1(CLDN1), occluding(OCLN), and zonula occludens 1(ZO-1) in the small intestine tissue, and reduced serum levels of inflammatory factors lipopolysaccharides(LPS), lipopolysaccharide-binding protein(LBP), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α). At the phylum level, the relative abundance of Bacteroidota decreased, while that of Firmicutes increased. Lipid-related metabolic pathways were significantly altered. In conclusion, based on the successful establishment of the mouse model of glucolipid metabolism disorder, this study confirmed that Dangua Humai Oral Liquid effectively modulates gut microbiota and mucosal barrier function, reduces serum inflammatory factor levels, and regulates lipid-related metabolic pathways, thereby ameliorating glucolipid metabolism disorder.
Animals ; Gastrointestinal Microbiome/drug effects* ; Mice ; Intestinal Mucosa/microbiology* ; Male ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred C57BL ; Humans ; Glycolipids/metabolism* ; Lipid Metabolism/drug effects* ; Administration, Oral ; Disease Models, Animal

Objective To explore the role and mechanism of mammalian target of rapamycin (mTOR) in oxidized low-density lipoprotein (oxLDL)-induced ferroptosis in vascular smooth muscle cells (VSMCs). Methods A model of oxLDL-induced VSMC ferroptosis was established. VSMCs were co-treated with either the mTOR inhibitor rapamycin or the autophagy inducer carbonyl cyanide m-chlorophenylhydrazone (CCCP), followed by detection of autophagy and ferroptosis-related indexes. Quantitative real-time PCR and Western blot were used respectively to analyze the expression of mTOR, glutathione peroxidase 4 (GPX4), sequestosome 1 (p62), and microtubule-associated protein 1 light chain 3 (LC3). Flow cytometry was employed to assess VSMC death. C11 BODIPY fluorescent staining was used to measure cellular lipid peroxidation levels. Colorimetric assays were performed to determine the contents of malondialdehyde (MDA), ferrous ion (Fe²⁺) and glutathione (GSH). Results oxLDL significantly upregulated mTOR expression in VSMCs, while increasing p62 expression and reducing LC3 expression, thereby suppressing VSMC autophagy. Compared with oxLDL treatment alone, rapamycin co-treatment reversed oxLDL-induced VSMC ferroptosis, as characterized by reduced VSMC death, increased GPX4 expression and GSH contents, along with decreased MDA content, Fe²⁺ content and lipid peroxidation levels. Similarly, CCCP co-treatment activated autophagy characterized by reduced p62 expression and elevated LC3 expression, which subsequently alleviated oxLDL-induced ferroptosis, showing reduced VSMC death, increased GPX4 expressions and GSH contents, and decreased MDA content, Fe²⁺ content and lipid peroxidation levels. Moreover, mTOR inhibition by rapamycin significantly reversed the oxLDL-induced upregulation of p62 and downregulation of LC3. Conclusion mTOR may promote oxLDL-induced VSMC ferroptosis by suppressing autophagy.
Ferroptosis/drug effects* ; Lipoproteins, LDL/metabolism* ; TOR Serine-Threonine Kinases/physiology* ; Autophagy/drug effects* ; Muscle, Smooth, Vascular/metabolism* ; Animals ; Rats ; Myocytes, Smooth Muscle/cytology* ; Cells, Cultured ; Lipid Peroxidation/drug effects* ; Sequestosome-1 Protein/genetics* ; Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism* ; Microtubule-Associated Proteins/genetics* ; Sirolimus/pharmacology*

Objective To investigate the effect and mechanism of baicalin on blood lipid metabolism and immune function in rats with gestational diabetes mellitus (GDM). Methods Female rats fed with high-fat and high-sugar diet and male rats fed with ordinary diet were caged together to prepare pregnant rats, and the GDM rat model was established by intraperitoneal injection of streptozotocin (35 mg/kg). GDM rats were randomly divided into a model group, a fasudil (FA) (RhoA/RocK inhibitor) group (10 mg/kg), low-dose (100 mg/kg) and high-dose (200 mg/kg) baicalin groups, and a high-dose baicalin combined with LPA (RhoA/RocK activator) group (200 mg/kg baicalin+1 mg/kg LPA ), with 12 rats in each group. Another 12 pregnant rats fed with high-fat and high-sugar diet were selected as the control group. After 2 weeks of corresponding drug intervention in each group, the level of fasting blood glucose (FBG) was detected by blood glucose meter. The level of fasting insulin (FINS) in serum was detected by ELISA, and the insulin resistance index (HOMA-IR) was calculated. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) in serum, and the levels of immunomodulator tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and IL-10 in peripheral blood were detected by the kit. The histopathological changes of liver were observed by HE staining. The proportion of T lymphocyte subsets in peripheral blood was detected by flow cytometry. The mRNA and protein expressions of Ras homolog gene family member A (RhoA), Rho associated coiled-coil forming protein kinase 1 (ROCK1), and ROCK2 in liver tissue were detected by real-time quantitative PCR and Western blot. Results Compared with the control group, the levels of FBG, FINS, HOMA-IR, ALT, AST, TG, TC, and LDL-C in serum, the levels of TNF-α, IL-6, the percentage of CD8⁺T cell in peripheral blood, and the mRNA and protein expression of RhoA, ROCK1, and ROCK2 in liver tissue in the model group were higher; the level of HDL-C in serum, the percentage of IL-10 levels, CD3⁺T cells, CD4⁺T cell, and CD4⁺T/CD8⁺T ratio in peripheral blood were lower. Compared with the model group, the levels of FBG, FINS, HOMA-IR, ALT, AST, TG, TC, and LDL-C in serum, the levels of TNF-α, IL-6, the percentage of CD8⁺T cell in peripheral blood, and the mRNA and protein expression of RhoA, ROCK1, and ROCK2 in liver tissue in the the FA group and low-dose and high-dose baicalin groups were lower; the level of HDL-C in serum, IL-10 level, the percentage of CD3⁺T cells, CD4⁺T cell, and CD4⁺T/CD8⁺T ratio in peripheral blood were higher. LPA could obviously weaken the improvement effects of baicalin on blood lipid metabolism and immune function in GDM rats. Conclusion Baicalin may improve blood lipid metabolism and immune function in GDM rats by inhibiting the RhoA/ROCK pathway.
Animals ; Female ; Diabetes, Gestational/metabolism* ; Pregnancy ; rho-Associated Kinases/genetics* ; Flavonoids/pharmacology* ; Rats ; rhoA GTP-Binding Protein/genetics* ; Lipid Metabolism/drug effects* ; Male ; Signal Transduction/drug effects* ; Rats, Sprague-Dawley ; Blood Glucose/metabolism* ; Lipids/blood* ; Tumor Necrosis Factor-alpha/blood* ; rho GTP-Binding Proteins

OBJECTIVES: To investigate the effect of pachymic acid on brown/beige adipocyte differentiation and lipid metabolism in preadipocytes. METHODS: 3T3-L1 MBX cells were induced to differentiate into beige adipocytes using a brown cocktail method. The impact of pachymic acid on the viability of 3T3-L1 MBX cells was evaluated using the CCK-8 assay. The formation of lipid droplets following treatment with pachymic acid was observed by oil red O staining. The mRNA expression levels of key browning genes, including uncoupling protein (Ucp) 1, the peroxisome proliferator activated receptor-γ coactivator (Pgc)-1α, and the PR domain-containing protein 16 (Prdm16), as well as the mRNA expression of sterol regulatory element-binding protein (Srebp) 1c, acetyl-coA carboxylase (Acc), fatty acid synthase (Fas), and hormone-sensitive triglyceride lipase (Hsl), adipose triglyceride lipase (Atgl), and carnitine palmitoyltransferase (Cpt) 1 were detected by quantitative reverse transcription polymerase chain reaction. The protein expression of Ucp1, Pgc-1a, and Prdm16 was detected by Western blotting. RESULTS: The 3T3-L1 MBX cells were induced in vitro to form beige adipocytes with high expression of key browning genes(Ucp1, Pgc-1α, and Prdm16), and beige adipose-marker genes (Cd137, Tbx1, and Tmem26). Concentrations range of 0-80 μmol/L pachymic acid were non-cytotoxic to 3T3-L1 MBX cells. Pachymic acid treatment significantly inhibited the differentiation of 3T3-L1 MBX cells, resulting in a notable decrease in lipid accumulation. There was a marked increase in the expression of key browning genes and their proteins products, such as Ucp1, Pgc-1α, and Prdm16, while the expressions of fat synthesis-related genes Srebp1c, Acc and Fas were significantly decreased (all P<0.05). The expressions of lipolysis-related genes (Hsl, Atgl, and Cpt1) were significantly increased (all P<0.05). Treatment with 20 μmol/L pachymic acid showed the most pronounced effect. CONCLUSIONS Pachymic acid can inhibit fat synthesis and promote lipid decomposition by regulating the brown formation and lipid differentiation of preadipocytes.
Animals ; Lipid Metabolism/drug effects* ; Mice ; Cell Differentiation/drug effects* ; Adipocytes, Beige/drug effects* ; 3T3-L1 Cells ; Adipocytes, Brown/drug effects* ; Triterpenes/pharmacology* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; Uncoupling Protein 1 ; Sterol Regulatory Element Binding Protein 1/metabolism*

OBJECTIVES: To determine the neuroprotective effects of berberine hydrochloride (BBR) against lead-induced injuries on the hippocampus of rats. METHODS: Wistar rats were exposed orally to doses of 100 and 500 ppm lead acetate for 1 and 2 months to develop subchronic and chronic lead poisening models, respectively. For treatment, BBR (50 mg/kg daily) was injected intraperitoneally to rats poisoned with lead. At the end of the experiment, the spatial learning and memory of rats were assessed using the Morris water maze test. Hippocampal tissue changes were examined by hematoxylin and eosin staining. The activity of antioxidant enzymes catalase, superoxide dismutase, glutathione peroxidase, and malondialdehyde levels as parameters of oxidative stress and antioxidant status of the hippocampus were evaluated. RESULTS: BBR reduced cognitive impairment in rats exposed to lead (P<0.05 or P<0.01). The resulting biochemical changes included a decrease in the activity of antioxidants and an increase in lipid peroxidation of the hippocampus of lead-exposed rats (P<0.05 or P<0.01), which were significantly modified by BBR (P<0.05). BBR also increased the density of healthy cells in the hippocampus of leadexposed rats (P<0.05). Significant changes in tissue morphology and biochemical factors of the hippocampus were observed in rats that received lead for 2 months (P<0.05). Most of these changes were insignificant in rats that received lead for 1 month. CONCLUSION BBR can improve oxidative tissue changes and hippocampal dysfunction in lead-exposed rats, which may be due to the strong antioxidant potential of BBR.
Animals ; Hippocampus/pathology* ; Rats, Wistar ; Antioxidants/pharmacology* ; Berberine/therapeutic use* ; Cognition/drug effects* ; Male ; Lead Poisoning/metabolism* ; Chronic Disease ; Oxidative Stress/drug effects* ; Maze Learning/drug effects* ; Rats ; Lipid Peroxidation/drug effects* ; Malondialdehyde/metabolism*

OBJECTIVE: To identify the underlying molecular mechanism of Modified Hu-Lu-Ba-Wan (MHW) in alleviating renal lesions in mice with diabetic kidney disease (DKD). METHODS: The db/db mice were divided into model group and MHW group according to a random number table, while db/m mice were settled as the control group (n=8 per group). The control and model groups were gavaged daily with distilled water [10 mL/(kg·d)], and the MHW group was treated with MHW [17.8 g/(kg·d)] for 6 weeks. After MHW administration for 6 weeks, indicators associated with glucolipid metabolism and urinary albumin were tested. Podocytes were observed by transmission electron microscopy. Kidney transcriptomics was performed after confirming therapeutic effects of MHW on DKD mice. The relevant target of MHW' effect in DKD was further determined by enzyme-linked immunosorbent assay, Western blot analysis, immunohistochemistry, and immunofluorescence staining. RESULTS: Compared with the model group, MHW improved glucose and lipid metabolism (P<0.05), and reduced lipid deposition in the kidney. Meanwhile, MHW reduced the excretion of urinary albumin (P<0.05) and ameliorated renal damage. Transcriptomic analysis revealed that the inflammation response, particularly the interleukin-17 (IL-17) signaling pathway, may be responsible for the effect of MHW on DKD. Furtherly, our results found that MHW inhibited IL-17A and alleviated early fibrosis in the diabetic kidney. CONCLUSION MHW ameliorated renal damage in DKD via inhibiting IL-17A, suggesting a potential strategy for DKD therapy.
Animals ; Diabetic Nephropathies/genetics* ; Interleukin-17/antagonists & inhibitors* ; Drugs, Chinese Herbal/therapeutic use* ; Male ; Kidney/ultrastructure* ; Podocytes/metabolism* ; Mice ; Albuminuria ; Lipid Metabolism/drug effects* ; Mice, Inbred C57BL

OBJECTIVE: To investigate the therapeutic potential of pseudolaric acid B (PAB) on non-alcoholic fatty liver disease (NAFLD) and its underlying molecular mechanism in vitro and in vivo. METHODS: Eight-week-old male C57BL/6J mice (n=32) were fed either a normal chow diet (NCD) or a high-fat diet (HFD) for 8 weeks. The HFD mice were divided into 3 groups according to a simple random method, including HFD, PAB low-dose [10 mg/(kg·d), PAB-L], and PAB high-dose [20 mg/(kg·d), PAB-H] groups. After 8 weeks of treatment, glucose metabolism and insulin resistance were assessed by oral glucose tolerance test (OGTT) and insulin tolerance test (ITT). Biochemical assays were used to measure the serum and cellular levels of total cholesterol (TC), triglycerides (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). White adipose tissue (WAT), brown adipose tissue (BAT) and liver tissue were subjected to hematoxylin and eosin (H&E) staining or Oil Red O staining to observe the alterations in adipose tissue and liver injury. PharmMapper and DisGeNet were used to predict the NAFLD-related PAB targets. Peroxisome proliferator-activated receptor alpha (PPARα) pathway involvement was suggested by Kyoto Encyclopedia of Genes and Genomes (KEGG) and search tool Retrieval of Interacting Genes (STRING) analyses. Luciferase reporter assay, cellular thermal shift assay (CETSA), and drug affinity responsive target stability assay (DARTS) were conducted to confirm direct binding of PAB with PPARα. Molecular dynamics simulations were applied to further validate target engagement. RT-qPCR and Western blot were performed to assess the downstream genes and proteins expression, and validated by PPARα inhibitor MK886. RESULTS: PAB significantly reduced serum TC, TG, LDL-C, AST, and ALT levels, and increased HDL-C level in HFD mice (P<0.01). Target prediction analysis indicated a significant correlation between PAB and PPARα pathway. PAB direct target binding with PPARα was confirmed through luciferase reporter assay, CETSA, and DARTS (P<0.05 or P<0.01). The target engagement between PAB and PPARα protein was further confirmed by molecular dynamics simulations and the top 3 amino acid residues, LEU321, MET355, and PHE273 showed the most significant changes in mutational energy. Subsequently, PAB upregulated the genes expressions involved in lipid metabolism and mitochondrial biogenesis downstream of PPARα (P<0.05 or P<0.01). Significantly, the PPARα inhibitor MK886 effectively reversed the lipid-lowering and PPARα activation properties of PAB (P<0.05 or P<0.01). CONCLUSION PAB mitigates lipid accumulation, ameliorates liver damage, and improves mitochondrial biogenesis by binding with PPARα, thus presenting a potential candidate for pharmaceutical development in the treatment of NAFLD.
Animals ; PPAR alpha/metabolism* ; Non-alcoholic Fatty Liver Disease/pathology* ; Male ; Mice, Inbred C57BL ; Lipid Metabolism/drug effects* ; Diterpenes/therapeutic use* ; Organelle Biogenesis ; Diet, High-Fat ; Humans ; Mice ; Liver/metabolism* ; Insulin Resistance ; Mitochondria/metabolism* ; Molecular Docking Simulation