OBJECTIVE: To Investigate the effects of lithocholic acid (LCA) on the balance between osteogenic and adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). METHODS: Twelve 10-week-old SPF C57BL/6J female mice were randomly divided into an experimental group (undergoing bilateral ovariectomy) and a control group (only removing the same volume of adipose tissue around the ovaries), with 6 mice in each group. The body mass was measured every week after operation. After 4 weeks post-surgery, the weight of mouse uterus was measured, femur specimens of the mice were taken for micro-CT scanning and three-dimensional reconstruction to analyze changes in bone mass. Tibia specimens were taken for HE staining to calculate the number and area of bone marrow adipocytes in the marrow cavity area. ELISA was used to detect the expression of bone turnover markers in the serum. Liver samples were subjected to real-time fluorescence quantitative PCR (RT-qPCR) to detect the expression of key genes related to bile acid metabolism, including cyp7a1, cyp7b1, cyp8b1, and cyp27a1. BMSCs were isolated by centrifugation from 2 C57BL/6J female mice (10-week-old). The third-generation cells were exposed to 0, 1, 10, and 100 μmol/L LCA, following which cell viability was evaluated using the cell counting kit 8 assay. Subsequently, alkaline phosphatase (ALP) staining and oil red O staining were conducted after 7 days of osteogenic and adipogenic induction. RT-qPCR was employed to analyze the expressions of osteogenic-related genes, namely ALP, Runt-related transcription factor 2 (Runx2), and osteocalcin (OCN), as well as adipogenic-related genes including Adiponectin (Adipoq), fatty acid binding protein 4 (FABP4), and peroxisome proliferator-activated receptor γ (PPARγ). RESULTS: Compared with the control group, the body mass of the mice in the experimental group increased, the uterus atrophied, the bone mass decreased, the bone marrow fat expanded, and the bone metabolism showed a high bone turnover state. RT-qPCR showed that the expressions of cyp7a1, cyp8b1, and cyp27a1, which were related to the key enzymes of bile acid metabolism in the liver, decreased significantly ( P<0.05), while the expression of cyp7b1 had no significant difference ( P>0.05). Intervention with LCA at concentrations of 1, 10, and 100 μmol/L did not demonstrate any apparent toxic effects on BMSCs. Furthermore, LCA inhibited the expressions of osteogenic-related genes (ALP, Runx2, and OCN) in a dose-dependent manner, resulting in a reduction in ALP staining positive area. Concurrently, LCA promoted the expressions of adipogenic-related genes (Adipoq, FABP4, and PPARγ), and an increase in oil red O staining positive area. CONCLUSION After menopause, the metabolism of bile acids is altered, and secondary bile acid LCA interferes with the balance of osteogenic and adipogenic differentiation of BMSCs, thereby affecting bone remodelling.
Female ; Mice ; Animals ; Core Binding Factor Alpha 1 Subunit/pharmacology* ; PPAR gamma/metabolism* ; Steroid 12-alpha-Hydroxylase/metabolism* ; Mice, Inbred C57BL ; Cell Differentiation ; Osteogenesis ; Mesenchymal Stem Cells ; Bile Acids and Salts/pharmacology* ; Bone Marrow Cells ; Cells, Cultured ; Azo Compounds

Humans ; PPAR gamma/metabolism* ; Multiple Sclerosis ; Transcription Factors/metabolism* ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha

OBJECTIVE: To observe the effect of Tongdu Tiaoshen (promoting the circulation of the governor vessel and regulating the spirit) electroacupuncture (EA) pretreatment on pyroptosis mediated by peroxisome proliferators-activated receptor γ (PPARγ) of the cerebral cortex in rats with cerebral ischemia reperfusion injury (CIRI) and explore the potential mechanism of EA for the prevention and treatment of CIRI. METHODS: A total of 110 clean-grade male SD rats were randomly divided into a sham-operation group, a model group, an EA group, an EA + inhibitor group and an agonist group, 22 rats in each group. In the EA group, before modeling, EA was applied to "Baihui" (GV 20), "Fengfu" (GV 16) and "Dazhui" (GV 14), with disperse-dense wave, 2 Hz/5 Hz in frequency, 1 to 2 mA in intensity, lasting 20 min; once a day, consecutively for 7 days. On the base of the intervention as the EA group, on the day 7, the intraperitoneal injection with the PPARγ inhibitor, GW9662 (10 mg/kg) was delivered in the EA + inhibitor group. In the agonist group, on the day 7, the PPARγ agonist, pioglitazone hydrochloride (10 mg/kg) was injected intraperitoneally. At the end of intervention, except the sham-operation group, the modified thread embolization method was adopted to establish the right CIRI model in the rats of the other groups. Using the score of the modified neurological severity score (mNSS), the neurological defect condition of rats was evaluated. TTC staining was adopted to detect the relative cerebral infarction volume of rat, TUNEL staining was used to detect apoptosis of cerebral cortical nerve cells and the transmission electron microscope was used to observe pyroptosis of cerebral cortical neural cells. The positive expression of PPARγ and nucleotide-binding to oligomerization domain-like receptor protein 3 (NLRP3) in the cerebral cortex was detected with the immunofluorescence staining. The protein expression of PPARγ, NLRP3, cysteinyl aspartate specific protease-1 (caspase-1), gasdermin D (GSDMD) and GSDMD-N terminal (GSDMD-N) in the cerebral cortex was detected with Western blot. Using the quantitative real-time fluorescence-PCR, the mRNA expression of PPARγ, NLRP3, caspase-1 and GSDMD of the cerebral cortex was detected. The contents of interleukin (IL)-1β and IL-18 in the cerebral cortex of rats were determined by ELISA. RESULTS: Compared with the sham-operation group, the mNSS, the relative cerebral infarction volume and the TUNEL positive cells rate were increased (P<0.01), pyroptosis was severe, the protein and mRNA expression levels of PPARγ, NLRP3, caspase-1 and GSDMD were elevated (P<0.01); and the protein expression of GSDMD-N and contents of IL-1β and IL-18 were increased (P<0.01) in the model group. When compared with the model group, the mNSS, the relative cerebral infarction volume and the TUNEL positive cells rate were decreased (P<0.01), pyroptosis was alleviated, the protein and mRNA expression levels of PPARγ were increased (P<0.01), the protein and mRNA expression levels of NLRP3, caspase-1 and GSDMD were decreased (P<0.01), the protein expression of GSDMD-N was reduced (P<0.01); and the contents of IL-1β and IL-18 were lower (P<0.01) in the EA group and the agonist group; while, in the EA + inhibitor group, the protein expression of PPARγ was increased (P<0.01), the protein and mRNA expression levels of NLRP3 and GSDMD were decreased (P<0.01, P<0.05), the mRNA expression of caspase-1 was reduced (P<0.01); and the contents of IL-1β and IL-18 were lower (P<0.01). When compared with the EA + inhibitor group, the mNSS, the relative cerebral infarction volume and the TUNEL positive cells rate were decreased (P<0.05, P<0.01), pyroptosis was alleviated, the protein and mRNA expression levels of PPARγ were increased (P<0.01), the protein and mRNA expression levels of NLRP3, caspase-1 and GSDMD were decreased (P<0.01), the protein expression of GSDMD-N was reduced (P<0.01); and the contents of IL-1β and IL-18 were declined (P<0.01) in the EA group. Compared with the agonist group, in the EA group, the relative cerebral infarction volume and the TUNEL positive cells rate were increased (P<0.05, P<0.01), the mRNA expression of PPARγ was decreased (P<0.01) and the protein expression of GSDMD-N was elevated (P<0.05); and the contents of IL-1β and IL-18 were higher (P<0.01). CONCLUSION Tongdu Tiaoshen EA pretreatment can attenuate the neurological impairment in the rats with CIRI, and the underlying mechanism is related to the up-regulation of PPARγ inducing the inhibition of NLRP3 in the cerebral cortex of rats so that pyroptosis is affected.
Male ; Animals ; Rats ; Rats, Sprague-Dawley ; PPAR gamma/genetics* ; Pyroptosis ; Interleukin-18 ; Electroacupuncture ; NLR Family, Pyrin Domain-Containing 3 Protein ; Cerebral Cortex ; Cerebral Infarction/therapy* ; Caspases ; RNA, Messenger

The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα^-/-+ND) group and ketogenic diet (PPARα^-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα^-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα^-/-+ND group, the PPARα^-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.
Animals ; Mice ; Adipose Tissue, Brown/metabolism* ; PPAR alpha/pharmacology* ; Diet, Ketogenic ; Uncoupling Protein 1/metabolism* ; Blood Glucose/metabolism* ; Temperature ; Mice, Inbred C57BL ; Liver ; Adipose Tissue/metabolism*

The study aimed to investigate the effect of anemoside B4(B4) on fatty acid metabolism in mice with colitis-associated cancer(CAC). The CAC model was established by azoxymethane(AOM)/dextran sodium sulfate(DSS) in mice. Mice were randomly divided into a normal group, a model group, and low-, medium-, and high-dose anemoside B4 groups. After the experiment, the length of the mouse colon and the size of the tumor were measured, and the pathological alterations in the mouse colon were observed using hematoxylin-eosin(HE) staining. The slices of the colon tumor were obtained for spatial metabolome analysis to analyze the distribution of fatty acid metabolism-related substances in the tumor. The mRNA levels of SREBP-1, FAS, ACCα, SCD-1, PPARα, ACOX, UCP-2, and CPT-1 were determined by real-time quantitative PCR(RT-qPCR). The results revealed that the model group showed decreased body weight(P<0.05) and colon length(P<0.001), increased number of tumors, and increased pathological score(P<0.01). Spatial metabolome analysis revealed that the content of fatty acids and their derivatives, carnitine, and phospholipid in the colon tumor was increased. RT-qPCR results indicated that fatty acid de novo synthesis and β-oxidation-related genes, such as SREBP-1, FASN, ACCα, SCD-1, ACOX, UCP-2, and CPT-1 mRNA expression levels increased considerably(P<0.05, P<0.001). After anemoside B4 administration, the colon length increased(P<0.01), and the number of tumors decreased in the high-dose anemoside B4 group(P<0.05). Additionally, spatial metabolome analysis showed that anemoside B4 could decrease the content of fatty acids and their derivatives, carnitine, and phospholipids in colon tumors. Meanwhile, anemoside B4 could also down-regulate the expression of FASN, ACCα, SCD-1, PPARα, ACOX, UCP-2, and CPT-1 in the colon(P<0.05, P<0.01, P<0.001). The findings of this study show that anemoside B4 may inhibit CAC via regulating fatty acid metabolism reprogramming.
Mice ; Animals ; Sterol Regulatory Element Binding Protein 1 ; Colitis-Associated Neoplasms ; PPAR alpha/genetics* ; Colonic Neoplasms/genetics* ; Colon ; Azoxymethane ; RNA, Messenger ; Dextran Sulfate ; Colitis/drug therapy* ; Mice, Inbred C57BL ; Disease Models, Animal

Hepatic lipid deposition is one of the basic manifestations of obesity, and nowadays pharmacological treatment is the most important tool. Punicalagin(PU), a polyphenol derived from pomegranate peel, is a potential anti-obesity substance. In this study, 60 C57BL/6J mice were randomly divided into a normal group and a model group. After establishing a model of simple obesity with a high-fat diet for 12 weeks, the successfully established rat models of obesity were then regrouped into a model group, an orlistat group, a PU low-dose group, a PU medium-dose group, and a PU high-dose group. The normal group was kept on routine diet and other groups continued to feed the high-fat diet. The body weight and food intake were measured and recorded weekly. After 8 weeks, the levels of the four lipids in the serum of each group of mice were determined by an automatic biochemical instrument. Oral glucose tole-rance and intraperitoneal insulin sensitivity were tested. Hemoxylin-eosin(HE) staining was applied to observe the hepatic and adipose tissues. The mRNA expression levels of peroxisome proliferators-activated receptor γ(PPARγ) and C/EBPα were determined by real-time quantitative polymerase chain reaction(Q-PCR), and the mRNA and protein expression levels of adenosine 5'-monophosphate-activated protein kinase(AMPK), anterior cingulate cortex(ACC), and carnitine palmitoyltransferase 1A(CPT1A) were determined by Western blot. Finally, the body mass, Lee's index, serum total glyceride(TG), serum total cholesterol(TC), and low-density lipoprotein cholesterol(LDL-C) levels were significantly higher and high-density lipoprotein cholesterol(HDL-C) levels were significantly lower in the model group as compared with the normal group. The fat deposition in the liver was significantly increased. The mRNA expression levels of hepatic PPARγ and C/EBPα and the protein expression level of ACC were increased, while the mRNA and protein expression levels of CPT-1α(CPT1A) and AMPK were decreased. After PU treatment, the above indexes of obese mice were reversed. In conclusion, PU can decrease the body weight of obese mice and control their food intake. It also plays a role in the regulation of lipid metabolism and glycometabolism metabolism, which can significantly improve hepatic fat deposition. Mechanistically, PU may regulate liver lipid deposition in obese mice by down-regulating lipid synthesis and up-regulating lipolysis through activation of the AMPK/ACC pathway.
Rats ; Mice ; Animals ; Mice, Obese ; AMP-Activated Protein Kinases/metabolism* ; PPAR gamma/metabolism* ; Mice, Inbred C57BL ; Liver/metabolism* ; Obesity/genetics* ; Body Weight ; Lipid Metabolism ; Diet, High-Fat/adverse effects* ; Lipids ; Cholesterol

To explore whether PPARA is involved in the process of ferroptosis in hepatoma cells, peroxisome proliferator activated receptor (PPARA) was comprehensively analyzed in hepatocellular carcinoma (HCC) through public database and experimental data, including the expression, the functions and the potential roles of tumor progression. The research design is experimental research,data analysis based on bioinformatics and cell experiment. From January 2022 to August 2022, relevant cell experiments were conducted in the Basic Medical Laboratory of the General Hospital of the Southern Theatre of the Chinese People's Liberation Army. The expression and the correlation with clinicopathologic features of PPARA in HCC were analyzed by The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. To study the protein expression of PPARA in HCC and normal tissues through the Human Protein Atlas (HPA). The protein-protein interaction (PPI) network between PPARA and the core factor of ferroptosis was constructed based on Search Tool for the Retrival of Interacting Genes/Protein (STRING) database, then, the correlation between PPARA and the core gene Glutamate-cysteine Ligase Catalytic Subunit (GCLC) was analyzed by Gene Expression Profiling Interactive Analysis (GEPIA). Assessed the expression of PPARA in HCC cell lines SK-HEP-1, SMMC-7721, MHCC-97H, BEL-7402 and normal liver cell L02 by Western Blot (WB) and the changes of PPARA expression after 48h treatment with ferroptosis inducer Erastin were observed. Single factor analysis of variance was used to compare the expression of PPARA between groups in GEPIA database. The expression of PPARA in GSE25097 and GSE112790 data was compared by rank sum test. Survival analysis was performed using time series test method. The difference of PPARA expression between clinical and pathological features was compared using the Kruskal-Wallis test. The correlation between the expression of GCLC and PPARA was compared by the method of Spearman correlation. The expression of PPARA in cell lines was compared by paired T test. The results showed that the RNA and protein expression of PPARA in HCC was lower than that in normal tissues (P<0.05). PPARA alterations were correlated with patient clinicopathological features and prognosis (P<0.05). The PPI constructed by STRING database suggests that PPARA interact with the key factors of ferroptosis, such as NFE2 like bZIP transcription factor 2 (NFE2L2), Heme Oxygenase 1 (HMOX1), Tumor Protein P53 (TP53), GCLC, Dipeptidyl Peptidase 4 (DPP4), Citrate Synthase (CS), Arachidonate 15-Lipoxygenase (ALOX15) and Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4). Furthermore, the PPARA was significantly associated with GCLC validated via GEPIA database(R=0.6, P<0.05). The expression of PPARA increased after treatment with ferroptosis inducer Erastin for 48 h by WB. In conclusion, the expression of PPARA is lower in HCC with a poor prognosis. PPARA interacts with GCLC in regulating ferroptosis in HCC.
Humans ; Carcinoma, Hepatocellular/pathology* ; Ferroptosis ; Liver Neoplasms/pathology* ; Peroxisome Proliferator-Activated Receptors/genetics*

OBJECTIVE: To explore the molecular pathological mechanism of liver metabolic disorder in severe spinal muscular atrophy (SMA). METHODS: The transgenic mice with type Ⅰ SMA (Smn^-/- SMN2^0tg/2tg) and littermate control mice (Smn^+/- SMN2^0tg/2tg) were observed for milk suckling behavior and body weight changes after birth. The mice with type Ⅰ SMA mice were given an intraperitoneal injection of 20% glucose solution or saline (15 μL/12 h), and their survival time was recorded. GO enrichment analysis was performed using the RNA-Seq data of the liver of type Ⅰ SMA and littermate control mice, and the results were verified using quantitative real-time PCR. Bisulfite sequencing was performed to examine CpG island methylation level in Fasn gene promoter region in the liver of the neonatal mice. RESULTS: The neonatal mice with type Ⅰ SMA showed normal milk suckling behavior but had lower body weight than the littermate control mice on the second day after birth. Intraperitoneal injection of glucose solution every 12 h significantly improved the median survival time of type Ⅰ SMA mice from 9±1.3 to 11± 1.5 days (P < 0.05). Analysis of the RNA-Seq data of the liver showed that the expression of the target genes of PPARα related to lipid metabolism and mitochondrial β oxidation were down-regulated in the liver of type Ⅰ SMA mice. Type Ⅰ SMA mice had higher methylation level of the Fasn promoter region in the liver than the littermate control mice (76.44% vs 58.67%). In primary cultures of hepatocytes from type Ⅰ SMA mice, treatment with 5-AzaC significantly up-regulated the expressions of the genes related to lipid metabolism by over 1 fold (P < 0.01). CONCLUSION Type Ⅰ SMA mice have liver metabolic disorder, and the down-regulation of the target genes of PPARα related to lipid and glucose metabolism due to persistent DNA methylation contributes to the progression of SMA.
Mice ; Animals ; PPAR alpha ; Liver Diseases ; Muscular Atrophy, Spinal/genetics* ; Mice, Transgenic ; Body Weight ; Glucose

OBJECTIVE: To investigate the effect of adipocytes in the bone marrow microenvironment of patients with multiple myeloma (MM) on the pathogenesis of MM. METHODS: Bone marrow adipocytes (BMA) in bone marrow smears of health donors (HD) and newly diagnosed MM (ND-MM) patients were evaluated with oil red O staining. The mesenchymal stem cells (MSC) from HD and ND-MM patients were isolated, and in vitro co-culture assay was used to explore the effects of MM cells on the adipogenic differentiation of MSC and the role of BMA in the survival and drug resistance of MM cells. The expression of adipogenic/osteogenic differentiation-related genes PPAR-γ, DLK1, DGAT1, FABP4, FASN and ALP both in MSC and MSC-derived adipocytes was determined with real-time quantitative PCR. The Western blot was employed to detect the expression levels of IL-6, IL-10, SDF-1α, TNF-α and IGF-1 in the supernatant with or without PPAR-γ inhibitor. RESULTS: The results of oil red O staining of bone marrow smears showed that BMA increased significantly in patients of ND-MM compared with the normal control group, and the BMA content was related to the disease status. The content of BMA decreased in the patients with effective chemotherapy. MM cells up-regulated the expression of MSC adipogenic differentiation-related genes PPAR-γ, DLK1, DGAT1, FABP4 and FASN, but the expression of osteogenic differentiation-related gene ALP was significantly down-regulated. This means that the direct consequence of the interaction between MM cells and MSC in the bone marrow microenvironment is to promote the differentiation of MSC into adipocytes at the expense of osteoblasts, and the cytokines detected in supernatant changed. PPAR-γ inhibitor G3335 could partially reverse the release of cytokines by BMA. Those results confirmed that BMA regulated the release of cytokines via PPAR-γ signal, and PPAR-γ inhibitor G3335 could distort PPAR-γ mediated BMA maturation and cytokines release. The increased BMA and related cytokines effectively promoted the proliferation, migration and drug resistance of MM cells. CONCLUSION The BMA and its associated cytokines are the promoting factors in the survival, proliferation and migration of MM cells. BMA can protect MM cells from drug-induced apoptosis and plays an important role in MM treatment failure and disease progression.
Humans ; Osteogenesis/genetics* ; Bone Marrow/metabolism* ; Multiple Myeloma/metabolism* ; Drug Resistance, Neoplasm ; Peroxisome Proliferator-Activated Receptors/pharmacology* ; Cell Differentiation ; Adipogenesis ; Cytokines/metabolism* ; Adipocytes/metabolism* ; Bone Marrow Cells/metabolism* ; Cells, Cultured ; PPAR gamma/pharmacology* ; Tumor Microenvironment

Melatonin receptor 1B (MT2, encoded by the MTNR1B gene), a high-affinity receptor for melatonin, is associated with glucose homeostasis including glucose uptake and transport. The rs10830963 variant in the MTNR1B gene is linked to glucose metabolism disorders including gestational diabetes mellitus (GDM); however, the relationship between MT2-mediated melatonin signaling and a high birth weight of GDM infants from maternal glucose abnormality remains poorly understood. This article aims to investigate the relationship between rs10830963 variants and GDM development, as well as the effects of MT2 receptor on glucose uptake and transport in trophoblasts. TaqMan-MGB (minor groove binder) probe quantitative real-time polymerase chain reaction (qPCR) assays were used for rs10930963 genotyping. MT2 expression in the placenta of GDM and normal pregnant women was detected by immunofluorescence, western blot, and qPCR. The relationship between MT2 and glucose transporters (GLUTs) or peroxisome proliferator-activated receptor γ (PPARγ) was established by western blot, and glucose consumption of trophoblasts was measured by a glucose assay kit. The results showed that the genotype and allele frequencies of rs10830963 were significantly different between GDM and normal pregnant women (P<0.05). The fasting, 1-h and 2-h plasma glucose levels of G-allele carriers were significantly higher than those of C-allele carriers (P<0.05). Besides, the protein and messenger RNA (mRNA) expression of MT2 in the placenta of GDM was significantly higher than that of normal pregnant women (P<0.05). Melatonin could stimulate glucose uptake and GLUT4 and PPARγ protein expression in trophoblasts, which could be attenuated by MT2 receptor knockdown. In conclusion, the rs10830963 variant was associated with an increased risk of GDM. The MT2 receptor is essential for melatonin to raise glucose uptake and transport, which may be mediated by PPARγ.
Female ; Humans ; Pregnancy ; Blood Glucose/metabolism* ; Diabetes, Gestational/metabolism* ; Glucose/metabolism* ; Melatonin/metabolism* ; Polymorphism, Genetic ; PPAR gamma ; Receptor, Melatonin, MT2/genetics*