BACKGROUND: Mitochondria, which harbor their own genome (mtDNA), have attracted attention due to the potential of mtDNA copy number (mtDNA-CN) as an indicator of mitochondrial dysfunction. Although mtDNA-CN has been proposed as a simple and accessible biomarker for metabolic disorders such as metabolic dysfunction-associated steatotic liver disease, the underlying mechanisms and the causal relationship remain insufficiently elucidated. In this investigation, we combined longitudinal epidemiological data, animal studies, and in vitro assays to elucidate the potential causal relationship between reduced mtDNA-CN and the development of steatotic liver disease (SLD). METHODS: We conducted a longitudinal study using data from a health examination cohort initiated in 1981 in Yakumo, Hokkaido, Japan. Data from examinations performed in 2015 and 2022 were analyzed, focusing on 76 subjects without SLD at baseline (2015) to assess the association between baseline mtDNA-CN and subsequent risk of SLD development. In addition, 28-day-old SD rats were fed ad libitum on a 45% high-fat diet and dissected at 2 and 8 weeks of age. Blood and liver mtDNA-CN were measured and compared at each feeding period. Additionally, in vitro experiments were performed using HepG2 cells treated with mitochondrial function inhibitors to induce mtDNA-CN depletion and to examine its impact on intracellular lipid accumulation. RESULTS: Epidemiological analysis showed that the subjects with low mtDNA-CN had a significantly higher odds ratio for developing SLD compared to high (odds ratio [95% confidence interval]: 4.93 [1.08-22.50]). Analysis of the animal model showed that 8 weeks of high-fat diet led to the development of fatty liver and a significant decrease in mtDNA-CN. A further 2 weeks of high-fat diet consumption resulted in a significant decrease in hepatic mtDNA-CN, despite the absence of fatty liver development, and a similar trend was observed for blood. Complementary in vitro experiments revealed that pharmacologically induced mitochondrial dysfunction led to a significant reduction in mtDNA-CN and was associated with increases in intracellular lipid accumulation in HepG2 cells. CONCLUSIONS Our findings suggest that reduced mtDNA-CN may contribute causally to SLD development and could serve as a convenient, noninvasive biomarker for early detection and risk assessment.
Animals ; DNA, Mitochondrial/genetics* ; Humans ; Male ; DNA Copy Number Variations ; Female ; Fatty Liver/blood* ; Rats ; Middle Aged ; Longitudinal Studies ; Rats, Sprague-Dawley ; Adult ; Japan/epidemiology* ; Aged ; Biomarkers/blood* ; Hep G2 Cells ; Diet, High-Fat/adverse effects*

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

OBJECTIVES: Recent evidence suggests that the gut may be a primary site of metformin action. However, studies on the effects of metformin on gut microbiota remain limited, and its impact on gut microbial metabolites such as short-/medium-chain fatty acids is unclear. This study aims to investigate the effects of metformin on gut microbiota, short-/medium-chain fatty acids, and associated metabolic benefits in high-fat diet rats. METHODS: Twenty-four Sprague-Dawley rats were randomly divided into 3 groups: 1) Normal diet group (ND group), fed standard chow; 2) high-fat diet group (HFD group), fed a high-fat diet; 3) high-fat diet + metformin treatment group (HFD+Met group), fed a high-fat diet for 8 weeks, followed by daily intragastric administration of metformin solution (150 mg/kg body weight) starting in week 9. At the end of the experiment, all rats were sacrificed, and serum, liver, and colonic contents were collected for assessment of glucose and lipid metabolism, liver pathology, gut microbiota composition, and the concentrations of short-/medium-chain fatty acids. RESULTS: Metformin significantly improved HFD-induced glucose and lipid metabolic disorders and liver injury. Compared with the HFD group, the HFD+Met group showed reduced abundance of Blautia, Romboutsia, Bilophila, and Bacteroides, while Lactobacillus abundance significantly increased (all P<0.05). Colonic contents of butyric acid, 2-methyl butyric acid, valeric acid, octanoic acid, and lauric acid were significantly elevated (all P<0.05), whereas acetic acid, isoheptanoic acid, and nonanoic acid levels were significantly decreased (all P<0.05). Spearman correlation analysis revealed that Lactobacillus abundance was negatively correlated with body weight gain and insulin resistance, while butyrate and valerate levels were negatively correlated with insulin resistance and liver injury (all P<0.05). CONCLUSIONS Metformin significantly increases the abundance of beneficial bacteria such as Lactobacillus and promotes the production of short-/medium-chain fatty acids including butyric, valeric, and lauric acid in the colonic contents of HFD rats, suggesting that metformin may regulate host metabolism through modulation of the gut microbiota.
Animals ; Metformin/pharmacology* ; Rats, Sprague-Dawley ; Diet, High-Fat/adverse effects* ; Rats ; Gastrointestinal Microbiome/drug effects* ; Male ; Fatty Acids, Volatile/metabolism* ; Fatty Acids/metabolism*

OBJECTIVES: To investigate the regulatory role of nucleotide-bound oligomerized domain-like receptor containing pyrin-domain protein 6 (NLRP6) in liver lipid metabolism and non-alcoholic fatty liver disease (NAFLD). METHODS: Mouse models with high-fat diet (HFD) feeding for 16 weeks (n=6) or with methionine choline-deficient diet (MCD) feeding for 8 weeks (n=6) were examined for the development of NAFLD using HE and oil red O staining, and hepatic expressions of NLRP6 were detected with RT-qPCR, Western blotting, and immunohistochemical staining. Cultured human hepatocytes (LO2 cells) with adenovirus-mediated NLRP6 overexpression or knock-down were treated with palmitic acid (PA) in the presence or absence of compound C (an AMPK inhibitor), and the changes in cellular lipid metabolism were examined by measuring triglyceride, ATP and β-hydroxybutyrate levels and using oil red staining, RT-qPCR, and Western blotting. RESULTS: HFD and MCD feeding both resulted in the development of NAFLD in mice, which showed significantly decreased NLRP6 expression in the liver. In PA-treated LO2 cells, NLRP6 overexpression significantly decreased cellular TG content and lipid deposition, while NLRP6 knockdown caused the opposite effects. NLRP6 overexpression in PA-treated LO2 cells also increased mRNA and protein expressions of PGC1A and CPT1A, levels of ATP and β-hydroxybutyrate, and the phosphorylation level of AMPK pathway; the oxidative decomposition of lipids induced by Ad-NLRP6 was inhibited by the use of AMPK inhibitors. CONCLUSIONS NLRP6 overexpression promotes lipid oxidation and decomposition through AMPK/CPT1A/PGC1A to alleviate lipid deposition in hepatocytes.
Non-alcoholic Fatty Liver Disease/metabolism* ; Animals ; Hepatocytes/metabolism* ; Lipid Metabolism ; Mice ; Humans ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; AMP-Activated Protein Kinases/metabolism* ; Carnitine O-Palmitoyltransferase/metabolism* ; Diet, High-Fat ; Male ; Mice, Inbred C57BL ; Signal Transduction

OBJECTIVES: To investigate the role of activating transcription factor 3 (ATF3) in atherosclerotic plaques for regulating inflammatory responses during atherosclerosis (AS) progression. METHODS: Human coronary artery specimens from autopsy cases were examined for ATF3 protein expression and localization using immunofluorescence staining and Western blotting. Apolipoprotein E-deficient (ApoE^-/-) mouse models of AS induced by high-fat diet (HFD) feeding for 12 weeks were subjected to tail vein injection of adeno-associated virus serotype 9 (AAV9) to knock down ATF3 expression. After an additional 5 weeks of HFD feeding, the mice were euthanized for analyzing structural changes of the aortic plaques, and the expression levels of ATF3, inflammatory factors (CD45, CD68, IL-1β, and TNF-α), and NF-κB pathway proteins (P-IKKα/β and P-NF-κB p65) were detected. In the cell experiment, THP-1-derived foam cells were transfected with an ATF3-overexpressing plasmid or an ATF3-specific siRNA to validate the relationship between ATF3 and NF‑κB signaling. RESULTS: In human atherosclerotic plaques, ATF3 expression was significantly elevated and partially co-localized with CD68. ATF3 knockout in ApoE^-/- mice significantly increased aortic plaque volume, upregulated the inflammatory factors, enhanced phosphorylation of the NF‑κB pathway proteins, and increased the expressions of VCAM1, MMP9, and MMP2 in the plaques. In THP-1-derived foam cells, ATF3 silencing caused activation of the NF‑κB pathway, while ATF3 overexpression suppressed the activity of the NF-κB pathway. CONCLUSIONS AS promotes ATF3 expression, and ATF3 deficiency exacerbates AS progression by enhancing plaque inflammation via activating the NF-κB pathway, suggesting the potential of ATF3 as a therapeutic target for AS.
Animals ; Activating Transcription Factor 3/metabolism* ; Signal Transduction ; NF-kappa B/metabolism* ; Humans ; Mice ; Plaque, Atherosclerotic/metabolism* ; Inflammation/metabolism* ; Apolipoproteins E ; Atherosclerosis/metabolism* ; Diet, High-Fat

OBJECTIVES: To investigate the therapeutic effect of electroacupuncture (EA) at Zusanli (ST36) acupoint on hyperlipidemia in mice and explore the underlying mechanisms. METHODS: Thirty C57BL/6J mice were equally randomized into normal diet group, high-fat diet (HFD) group, and EA group. The changes in blood lipids and serum malondialdehyde (MDA) content of the mice were evaluated, and histopathological changes and lipid accumulation in the liver were observed using Oil red O staining (ORO). The expressions of NLRP3, TLR4, and IL-1β proteins in the colon tissues were detected with Western blotting, and gut microbiota changes were analyzed using 16S rDNA sequencing. RESULTS: In mice with HFD feeding, 16 weeks of EA treatment significantly lowered body weight and serum TC, TG, LDL-C and MDA levels, obviously reduced lipid accumulation in the liver, and ameliorated HFD-induced elevations of protein expressions of NLRP3, TLR4, and IL-1β. 16S rRNA sequencing revealed that EA significantly altered gut microbiota composition, and increased the diversity and relative abundance of beneficial bacterial groups such as Muribaculaceae and Lachnospiraceae NK4A136_group. CONCLUSIONS Electroacupuncture at ST36 alleviates blood lipid disorders in hyperlipidemic mice possibly by improving intestinal microbiota structure, promoting degradation of high-caloric carbohydrates, cholesterol lipid metabolism and intestinal mucosa repair, and reducing toxin leakage, lipid peroxides, and liver fat deposition.
Animals ; Electroacupuncture ; Gastrointestinal Microbiome ; Hyperlipidemias/blood* ; Mice, Inbred C57BL ; Mice ; Diet, High-Fat ; Toll-Like Receptor 4/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein ; Acupuncture Points ; Male ; Lipids/blood* ; Interleukin-1beta/metabolism* ; Liver/metabolism*

OBJECTIVES: To explore the molecular mechanism of Jiangzhi Huaban Decoction (JZHBD) for improving atherosclerosis through the "qi meridian-blood channels" pathway. METHODS: ApoE^-/- mouse models of atherosclerosis were established by high-fat diet feeding for 8 weeks, with C57BL/6 mice on a normal diet as the controls. Forty ApoE^-/- mouse models were randomized into model group, low-, medium-, and high-dose JZHBD treatment groups, and atorvastatin treatment group (n=8) for their respective treatments for 8 weeks. The changes in body weight and overall condition of the mice were monitored weekly. After the treatments, serum levels of TC, TG, HDL-C, LDL-C, TBA, ALT, and AST of the mice were measured, pathological changes in the liver and aortic root plaques were examined with HE staining, and lipid accumulation in the liver and aortic wall was assessed using Oil Red O staining. The core molecular mechanism was studied through transcriptomics, and the expressions of the key pathway proteins were confirmed using Western blotting and immunohistochemistry. RESULTS: Treatment with JZHBD significantly reduced blood lipid and total bile acid levels, improved liver function and hepatic steatosis, and decreased aortic lipid deposition and plaque area in the mouse models of atherosclerosis. Transcriptomic analysis suggested that the therapeutic mechanism of JZHBD involved reverse cholesterol transport, PPAR signaling, and the inflammatory pathways. In atherosclerotic mice, JZHBD treatment obviously up-regulated hepatic expressions of PPARγ, LXRα, ABCA1, ABCG1, and CYP7A1, down-regulated hepatic expressions of p-p65/p65, IL-6, IL1β in the liver, increased ABCG5 and ABCG8 expressions in the intestines, and decreased ICAM-1 and VCAM-1 expressions in the aortic plaques. CONCLUSIONS JZHBD improves atherosclerotic vascular damage and plaque formation possibly by regulating hepatic reverse cholesterol transport and inflammation via modulating the hepatic PPARγ/LXRα/NF-κB signaling pathway.
Animals ; Drugs, Chinese Herbal/therapeutic use* ; Mice, Inbred C57BL ; Plaque, Atherosclerotic/metabolism* ; Liver/metabolism* ; Mice ; Atherosclerosis/metabolism* ; Cholesterol/metabolism* ; PPAR gamma/metabolism* ; Male ; Diet, High-Fat ; Biological Transport

This study investigates the role of Interleukin 17 (IL-17) in exacerbating periapical lesions caused by Porphyromonas gingivalis (Pg) lipopolysaccharides (LPS) in the context of metabolic disease and its potential impact on glucose tolerance. Researchers developed a unique mouse model where mice were monocolonized with Pg to induce periapical lesions. After 1 month, they were fed a high-fat diet (HFD) for 2 months to simulate metabolic disease and oral microbiota dysbiosis. To explore the role of LPS from Pg, wild-type (WT) mice were challenged with purified LPS from Porphyromonas gingivalis, as well as with LPS-depleted and non-depleted Pg bacteria; IL-17 knockout (KO) mice were also included to assess the role of IL-17 signaling. The impact on bone lysis, periapical injury, glucose intolerance, and immune response was assessed. Results showed that in WT mice, the presence of LPS significantly worsened bone lysis, Th17 cell recruitment, and periapical injury. IL-17 KO mice exhibited reduced bone loss, glucose intolerance, and immune cell infiltration. Additionally, inflammatory markers in adipose tissue were lower in IL-17 KO mice, despite increased dysbiosis. The findings suggest that IL-17 plays a critical role in amplifying Pg-induced periapical lesions and systemic metabolic disturbances. Targeting IL-17 recruitment could offer a novel approach to improving glycemic control and reducing type 2 diabetes (T2D) risk in individuals with periapical disease.
Animals ; Porphyromonas gingivalis/immunology* ; Th17 Cells/immunology* ; Lipopolysaccharides/immunology* ; Mice ; Glucose Intolerance/microbiology* ; Interleukin-17/metabolism* ; Mice, Knockout ; Mice, Inbred C57BL ; Disease Models, Animal ; Diet, High-Fat ; Periapical Diseases/microbiology* ; Male ; Dysbiosis

OBJECTIVE: Prunella vulgaris L. has long been used for liver protection according to traditional Chinese medicine theory and has been proven by modern pharmacological research to have multiple potential liver-protective effects. However, its effects on non-alcoholic steatohepatitis (NASH) are currently uncertain. Our study explores the effects of P. vulgaris polysaccharides on NASH and intestinal homeostasis. METHODS: An aqueous extract of the dried fruit spikes of P. vulgaris was precipitated in an 85% ethanol solution (PVE85) to extract crude polysaccharides from the herb. A choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) was administrated to male C57BL/6 mice to establish a NASH animal model. After 4 weeks, the PVE85 group was orally administered PVE85 (200 mg/[kg·d]), while the control group and CDAHFD group were orally administered vehicle for 6 weeks. Quantitative real-time polymerase chain reaction analysis, Western blotting, immunohistochemistry and other methods were used to assess the impact of PVE85 on the liver in mice with NASH. 16S rRNA gene amplicon analysis was employed to evaluate the gut microbiota abundance and diversity in each group to examine alterations at various taxonomic levels. RESULTS: PVE85 significantly reversed the course of NASH in mice. mRNA levels of inflammatory mediators associated with NASH and protein expression of hepatic nucleotide-binding leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) were significantly reduced after PVE85 treatment. Moreover, PVE85 attenuated the thickening and cross-linking of collagen fibres and inhibited the expression of fibrosis-related mRNAs in the livers of NASH mice. Intriguingly, PVE85 restored changes in the gut microbiota and improved intestinal barrier dysfunction induced by NASH by increasing the abundance of Actinobacteria and reducing the abundance of Proteobacteria at the phylum level. PVE85 had significant activity in reducing the relative abundance of Clostridiaceae at the family levels. PVE85 markedly enhanced the abundance of some beneficial micro-organisms at various taxonomic levels as well. Additionally, the physicochemical environment of the intestine was effectively improved, involving an increase in the density of intestinal villi, normalization of the intestinal pH, and improvement of intestinal permeability. CONCLUSION PVE85 can reduce hepatic lipid overaccumulation, inflammation, and fibrosis in an animal model of CDAHFD-induced NASH and improve the intestinal microbial composition and intestinal structure. Please cite this article as: Zhu MJ, Song YJ, Rao PL, Gu WY, Xu Y, Xu HX. Therapeutic role of Prunella vulgaris L. polysaccharides in non-alcoholic steatohepatitis and gut dysbiosis. J Integr Med. 2025; 2025; 23(3): 297-308.
Animals ; Non-alcoholic Fatty Liver Disease/drug therapy* ; Male ; Dysbiosis/drug therapy* ; Mice, Inbred C57BL ; Gastrointestinal Microbiome/drug effects* ; Polysaccharides/therapeutic use* ; Prunella/chemistry* ; Mice ; Liver/metabolism* ; Plant Extracts/therapeutic use* ; Disease Models, Animal ; Diet, High-Fat

The current study aimed to clarify the roles of apolipoprotein A5 (ApoA5) and milk fat globule-epidermal growth factor 8 (Mfge8) in regulating myocardial lipid deposition and the regulatory relationship between them. The serum levels of ApoA5 and Mfge8 in obese and healthy people were compared, and the obesity mouse model induced by the high-fat diet (HFD) was established. In addition, primary cardiomyocytes were purified and identified from the hearts of suckling mice. The 0.8 mmol/L sodium palmitate treatment was used to establish the lipid deposition cardiomyocyte model in vitro. ApoA5-overexpressing adenovirus was used to observe its effects on cardiac function and lipids. The expressions of the fatty acid uptake-related molecules and Mfge8 on transcription or translation levels were detected. Co-immunoprecipitation was used to verify the interaction between ApoA5 and Mfge8 proteins. Immunofluorescence was used to observe the co-localization of Mfge8 protein with ApoA5 or lysosome-associated membrane protein 2 (LAMP2). Recombinant rMfge8 was added to cardiomyocytes to investigate the regulatory mechanism of ApoA5 on Mfge8. The results showed that participants in the simple obesity group had a significant decrease in serum ApoA5 levels (P < 0.05) and a significant increase in Mfge8 levels (P < 0.05) in comparison with the healthy control group. The adenovirus treatment successfully overexpressed ApoA5 in HFD-fed obese mice and palmitic acid-induced lipid deposition cardiomyocytes, respectively. ApoA5 reduced the weight of HFD-fed obese mice (P < 0.05), shortened left ventricular isovolumic relaxation time (IVRT), increased left ventricular ejection fraction (LVEF), and significantly reduced plasma levels of triglycerides (TG) and cholesterol (CHOL) (P < 0.05). In myocardial tissue and cardiomyocytes, the overexpression of ApoA5 significantly reduced the deposition of TG (P < 0.05), transcription of fatty acid translocase (FAT/CD36) (P < 0.05), fatty acid-binding protein (FABP) (P < 0.05), and fatty acid transport protein (FATP) (P < 0.05), and protein expression of Mfge8 (P < 0.05), while the transcription levels of Mfge8 were not significantly altered (P > 0.05). In vitro, the Mfge8 protein was captured using ApoA5 as bait protein, indicating a direct interaction between them. Overexpression of ApoA5 led to an increase in co-localization of Mfge8 with ApoA5 or LAMP2 in cardiomyocytes under lipid deposition status. On this basis, exogenous added recombinant rMfge8 counteracted the improvement of lipid deposition in cardiomyocytes by ApoA5. The above results indicate that the overexpression of ApoA5 can reduce fatty acid uptake in myocardial cells under lipid deposition status by regulating the content and cellular localization of Mfge8 protein, thereby significantly reducing myocardial lipid deposition and improving cardiac diastolic and systolic function.
Animals ; Humans ; Mice ; Myocytes, Cardiac/metabolism* ; Obesity/physiopathology* ; Male ; Apolipoprotein A-V/blood* ; Lipid Metabolism/physiology* ; Milk Proteins/blood* ; Myocardium/metabolism* ; Diet, High-Fat ; Antigens, Surface/physiology* ; Mice, Inbred C57BL ; Cells, Cultured ; Female