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1.
Bol. latinoam. Caribe plantas med. aromát ; 23(4): 516-522, jul. 2024. graf, ilus
Article in English | LILACS | ID: biblio-1538029

ABSTRACT

This article aimed to discuss the protection of trans - nerolidol on vascular endothelial cells (ECs) injured by lipopolysac charides. ECs were divided into four groups: normal, model, low and high dose trans - nerolidol treatment groups. The cell survival rate and the contents of NO in the cell culture supernatant were determined. The protein expression and transcript level of pe roxisome proliferator - activated receptor - γ (PPARγ), endothelial nitric oxide synthase (eNOS), and inducible nitric oxide synthase (iNOS) were determined by western blotting and RT - PCR respectively. Compared with the normal group, cell livability, protein e xpression and mRNA transcript level of PPARγ and eNOS decreased, NO contents, protein expression and mRNA transcript tlevel of iNOS increased in model group significantly. Compared with model group, all the changes recovered in different degree in treatmen t groups. Hence, it was concluded that trans - nerolidol can alleviate the ECs injuryby the regulation of iNOS/eNOS through activating PPARγ in a dose - dependent manner


Este artículo tiene como objetivo discutir la protección del trans - nerolidol en las células endoteliales vasculares (CE) dañadas por lipopolisacáridos. Las CE se di vidieron en cuatro grupos: normal, modelo, grupos de tratamiento con trans - nerolidol de baja y alta dosis. Se determinó la tasa de supervivencia de las células y los contenidos de óxido nítrico (NO) en el sobrenadante del cultivo celular. La expresión de p roteínas y el nivel de transcripción del receptor activado por proliferadores de peroxisomas - γ (PPARγ), el óxido nítrico sint et asa endotelial (eNOS) y el óxido nítrico sint et asa inducible (iNOS) se determinaron mediante western blot y RT - PCR, respectivamen te. En comparación con el grupo normal, la viabilidad celular, la expresión de proteínas y el nivel de transcripción de PPARγ y eNOS disminuyeron, los contenidos de NO, la expresión de proteínas y el nivel de transcripción de iNOS aumentaron significativam ente en el grupo modelo. En comparación con el grupo modelo, todos los cambios se recuperaron en diferentes grados en los grupos de tratamiento. Por lo tanto, se concluyó que el trans - nerolidol puede aliviar el daño en las CE regulando iNOS/eNOS a través d e la activación de PPARγ de manera dependiente de la dosis.


Subject(s)
Sesquiterpenes/pharmacology , Lipopolysaccharides/pharmacology , Endothelial Cells/drug effects
2.
Braz. j. med. biol. res ; 57: e13235, fev.2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1550145

ABSTRACT

Abstract The imbalance between pro-inflammatory M1 and anti-inflammatory M2 macrophages plays a critical role in the pathogenesis of sepsis-induced acute lung injury (ALI). Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) may modulate macrophage polarization toward the M2 phenotype by altering mitochondrial activity. This study aimed to investigate the role of the PGC-1α agonist pioglitazone (PGZ) in modulating sepsis-induced ALI. A mouse model of sepsis-induced ALI was established using cecal ligation and puncture (CLP). An in vitro model was created by stimulating MH-S cells with lipopolysaccharide (LPS). qRT-PCR was used to measure mRNA levels of M1 markers iNOS and MHC-II and M2 markers Arg1 and CD206 to evaluate macrophage polarization. Western blotting detected expression of peroxisome proliferator-activated receptor gamma (PPARγ) PGC-1α, and mitochondrial biogenesis proteins NRF1, NRF2, and mtTFA. To assess mitochondrial content and function, reactive oxygen species levels were detected by dihydroethidium staining, and mitochondrial DNA copy number was measured by qRT-PCR. In the CLP-induced ALI mouse model, lung tissues exhibited reduced PGC-1α expression. PGZ treatment rescued PGC-1α expression and alleviated lung injury, as evidenced by decreased lung wet-to-dry weight ratio, pro-inflammatory cytokine secretion (tumor necrosis factor-α, interleukin-1β, interleukin-6), and enhanced M2 macrophage polarization. Mechanistic investigations revealed that PGZ activated the PPARγ/PGC-1α/mitochondrial protection pathway to prevent sepsis-induced ALI by inhibiting M1 macrophage polarization. These results may provide new insights and evidence for developing PGZ as a potential ALI therapy.

3.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 176-186, 2024.
Article in Chinese | WPRIM | ID: wpr-1016477

ABSTRACT

ObjectiveThrough the correlation analysis between intestinal absorption profile and inhibition of macrophage foaming, the pharmacodynamic components of Zhuriheng dripping pills(ZRH) were explored to provide a basis for establishing its quality standard. MethodIntestinal absorption fluids with 0, 5, 10, 15, 20 times clinical equivalent doses were prepared by a rat everted gut sac(EGS), and the oxidized low density lipoprotein(ox-LDL)-induced RAW264.7 macrophage foaming model was used to investigate the effect of intestinal absorption fluid with different doses on the accumulation of lipids in RAW264.7 cells by oil red O staining and cholesterol content determination, and to screen for the optimal dose. Ultra performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry(UPLC-Q-Exactive Orbitrap MS) was used to analyze and identify intestinal absorption fractions of ZRH intestinal absorption fluids, and partial least squares-discriminant analysis(PLS-DA) and orthogonal partial least squares-discriminant analysis(OPLS-DA) were performed on different doses of ZRH intestinal absorption fluids using SIMCA 13.0 with peak area as the independent variable and the pharmacodynamic indicators as the dependent variables to screen the compounds with variable importance in the projection(VIP) value>1.0 as contributing components, and Pearson correlation analysis was used to determine the spectral effect relationship, determined the compounds and positive correlation with pharmacodynamic were as active ingredients. Molecular docking was used to verify the binding energy of peroxisome proliferator-activated receptor α(PPARα), PPARγ, PPARβ, human retinoid X receptor α(RXRA) and nuclear transcription factor-κB(NF-κB) with the active ingredients in ZRH intestinal absorption fluids. Real-time fluorescence quantitative polymerase chain reaction(Real-time PCR) was performed to detect the mRNA levels of PPARγ, scavenger receptor A1(SRA1) and adenosine triphosphate-binding cassette transporter A1(ABCA1) in RAW264.7 cells, Westen blot was used to detect the expression level of PPARγ protein in RAW264.7 cells, and enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of interleukin(IL)-1β and NF-κB in RAW264.7 cells. ResultAccording to the results of oil red O staining and cholesterol content determination, the ZRH intestinal absorption fluids could significantly reduce macrophage foaming, and intestinal absorption fluids with 15, 20 times clinical equivalent doses had the best effect, the 15-fold ZRH intestinal absorption fluid was finally determined as the study subject. Spectral effect relationship showed that 52 corresponding peaks in the ZRH-containing intestinal fluid were positively correlated with the efficacy, including organic acids, phenylpropanoids, iridoids, flavonoids, bile acids, coumarins and chromones. Target validation results showed that 86.9%-96.2% of the total components processed good binding activities with the key targets of PPARα, PPARγ, PPARβ, RXRA and NF-κB, and the docking energy values were all less than -6.0 kcal·mol-1(1 cal≈4.19 J). The results of validation showed that, compared with the normal group, the model group showed a significant increase in the levels of SRA1 and PPARγ mRNA expression, a significant decrease in ABCA1 mRNA expression, a significant increase in the level of PPARγ protein expression, and a significant increase in the levels of IL-1β and NF-κB(P<0.01), compared with the model group, the 15-fold intestinal absorption fluid group showed a significant decrease in the levels of SRA1 and PPARγ mRNA expression(P<0.05, P<0.01), ABCA1 mRNA expression level was significantly up-regulated, the levels of IL-1β and NF-κB were significantly reduced(P<0.01), and PPARγ protein expression level was significantly reduced(P<0.05). ConclusionThis study identifies 52 components and their metabolites in ZRH intestinal absorption fluid that are positively correlated with the inhibition of macrophage foaming, which may be related to the regulation of the PPARs pathway in cells and the reduction of the levels of inflammatory factors, and can provide a reference for the quality control and clinical application of ZRH.

4.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 233-244, 2024.
Article in Chinese | WPRIM | ID: wpr-1012713

ABSTRACT

Ulcerative colitis (UC) is a chronic inflammatory bowel disease primarily affecting the colon and rectum, with the typical symptoms such as abdominal pain, bloody diarrhea, and tenesmus. The pathogenesis of UC remains to be fully elucidated. The disease is prone to recurrence, seriously affecting the patients' quality of life. Conventional therapies for UC have limitations, including unsatisfactory clinical efficacy, lengthy courses, and adverse reactions. Therefore, there is an urgent need to explore new therapeutic agents. Peroxisome proliferator-activated receptor gamma (PPARγ), a ligand-dependent nuclear receptor protein that plays a crucial role in maintaining intestinal homeostasis, is closely associated with the onset and development of UC. Traditional Chinese medicine (TCM) has advantages such as multi-targeting and mild side effects in the treatment of UC. Recent studies have shown that TCM can exert the therapeutic effects on UC by modulating PPARγ. The TCM methods for regulating PPARγ include clearing heat, drying dampness, moving Qi, activating blood, resolving stasis, invigorating the spleen, warming the kidney, and treating with both tonification and elimination. On one hand, TCM directly activates PPARγ or mediates signaling pathways such as nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), Toll-like receptor 4 (TLR4), and regulates helper T cell 17 (Th17)/regulatory T cell (Treg) balance to promote macrophage polarization from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype, thereby inhibiting intestinal inflammation. On the other hand, TCM regulates the intestinal metabolism to activate PPARγ, lower the nitrate level, and maintain local hypoxia. In this way, it can restore the balance between specialized anaerobes and facultative anaerobes, thereby improving the gut microbiota and treating UC. This article summarizes the role of PPARγ in UC and reviews the research progress of TCM in treating UC by intervening in PPARγ in the last five years, aiming to give insights into the treatment and new drug development for UC.

5.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 75-82, 2024.
Article in Chinese | WPRIM | ID: wpr-1006557

ABSTRACT

ObjectiveTo investigate the effect of Tangbikang granules on oxidative stress of sciatic nerve in diabetic rats by regulating adenylate activated protein kinase/peroxisome proliferator-activated receptor γ coactivator-1α/mitochondrial Sirtuins 3 (AMPK/PGC-1α/SIRT3) signaling pathway. MethodThe spontaneous obesity type 2 diabetes model was established using ZDF rats. After modeling, they were randomly divided into high, medium, and low dose Tangbikang granule groups (2.5, 1.25, 0.625 g·kg-1·d-1) and lipoic acid group (0.026 8 g·kg-1·d-1), and the normal group was set up. The rats were administered continuously for 12 weeks after modeling. The blood glucose of rats was detected before intervention and at 4, 8, 12 weeks after intervention. At the 12th week, motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNCV), nerve blood flow velocity, mechanical pain threshold, and thermal pain threshold were detected. The sciatic nerve was taken for hematoxylin-eosin (HE) staining to observe the tissue morphology. The ultrastructure of the sciatic nerve was observed by transmission electron microscope. The expression levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) in sciatic nerve were determined by enzyme-related immunosorbent assay (ELISA). The mRNA expressions of AMPKα, AMPKβ, PGC-1α, and SIRT3 in sciatic nerve were determined by real-time polymerase chain reaction (Real-time PCR). ResultCompared with the normal group, fasting blood glucose in the model group was increased at each time point (P<0.01). The mechanical pain threshold was decreased (P<0.05), and the incubation time of the hot plate was extended (P<0.01). MNCV, SNCV, and nerve blood flow velocity decreased (P<0.05). The expression level of SOD was decreased (P<0.01). The expression levels of MDA, IL-1β, and TNF-α were increased (P<0.01). The mRNA expression levels of AMPKα, AMPKβ, PGC-1α, and SIRT3 were decreased (P<0.01). The structure of sciatic nerve fibers in the model group was loose, and the arrangement was disordered. The demyelination change was obvious. Compared with the model group, the fasting blood glucose of rats in the high dose Tangbikang granule group was decreased after the intervention of eight weeks and 12 weeks (P<0.01). The mechanical pain threshold increased (P<0.05). The incubation time of the hot plate was shortened (P<0.01). MNCV, SNCV, and Flux increased (P<0.05). The expression level of SOD was increased (P<0.01). The expression levels of MDA, IL-1β, and TNF-α were decreased (P<0.01). The mRNA expression levels of AMPKα, AMPKβ, PGC-1α, and SIRT3 were increased (P<0.01). The sciatic nerve fibers in the high-dose Tangbikang granule group were tighter and more neatly arranged, with only a few demyelinating changes. The high, medium, and low dose Tangbikang granule groups showed a significant dose-effect trend. ConclusionTangbikang granules may improve sciatic nerve function in diabetic rats by regulating AMPK/PGC-1α/SIRT3 signaling pathway partly to inhibit oxidative stress.

6.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 71-78, 2024.
Article in Chinese | WPRIM | ID: wpr-1003410

ABSTRACT

ObjectiveTo investigate the effect and mechanism of total saponins from Panax japonicus (TSPJ) on white adipose tissue (WAT) browning/brown adipose tissue (BAT) activation in C57BL6/J male mice fed on a high-fat diet (HFD). MethodThirty-two C57BL6/J male mice (8-week-old) were randomly divided into a normal group, a model group, a low-dose TSPJ group, and a high-dose TSPJ group. The mice in the low-dose and high-dose TSPJ groups were given TSPJ for four months by gavage at 25, 75 mg·kg-1·d-1, respectively, and those in the other groups were given 0.5% sodium carboxymethyl cellulose (CMC-Na) accordingly. After four months of feeding, all mice were placed at 4 ℃ for acute cold exposure, and the core body temperature was monitored. Subsequently, all mice were sacrificed, and BAT and inguinal WAT (iWAT) were separated rapidly to detect the corresponding indexes. Hematoxylin-eosin (HE) staining was used to observe the morphological changes in each group. The effect of TSPJ on the mRNA expression of uncoupling protein 1 (UCP1), fatty acid-binding protein 4 (FABP4), cytochrome C (CytC), PR domain-containing protein 16 (PRDM16), elongation of very long chain fatty acids protein 3 (ELOVL3), peroxisome proliferator-activated receptor γ (PPARγ), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) in iWAT and BAT was detected by Real-time polymerase chain reaction (Real-time PCR). Western blot was also used to detect the protein expression of UCP1, PRDM16, PPARγ, and PGC-1α in BAT and iWAT of each group. The effect of TSPJ on UCP1 expression in BAT and iWAT was detected by immunohistochemistry. Result① Compared with the model group, TSPJ could decrease the body weight and proportions of iWAT and BAT in the HFD-induced mice (P<0.05, P<0.01). ② The body temperature of mice in the model group decreased compared with that in the normal group in the acute cold exposure tolerance test (P<0.05). The body temperature in the high-dose TSPJ group increased compared with that in the model group (P<0.01). ③ Compared with the normal group, the model group showed increased adipocyte diameter in iWAT and BAT and decreased number of adipocytes per unit area. Compared with the model group, the TSPJ groups showed significantly reduced cell diameter and increased number of cells per unit area, especially in the high-dose TSPJ group. ④ Compared with the normal group, the model group showed decreased mRNA expression of FABP4, UCP1, CytC, PRDM16, ELOVL3, PGC-1α, and PPARγ in adipose tissues of mice (P<0.05, P<0.01). Compared with the model group, after intervention with TSPJ, the mRNA expression was significantly up-regulated (P<0.05, P<0.01). ⑤ Compared with the normal group, the model group showed decreased protein expression of UCP1, PRDM16, PPARγ, and PGC-1α in adipose tissues of mice (P<0.05, P<0.01). Compared with the model group, after intervention with TSPJ, the protein expression increased significantly (P<0.05, P<0.01). ConclusionTSPJ could induce the browning of iWAT/BAT activation and enhance adaptive thermogenesis in obese mice induced by HFD. The underlying mechanism may be attributed to the activation of the PPARγ/PGC-1α signaling pathway.

7.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 77-86, 2024.
Article in Chinese | WPRIM | ID: wpr-999163

ABSTRACT

ObjectiveTo investigate the effect of Gegen Qinliantang on glucose and lipid metabolism in the rat model of catch-up growth (CUG) induced by a high-fat diet and the underlying mechanism. MethodA total of 60 SD rats were randomized into a normal control group (n=18) and a modeling group (n=42). The rat model of CUG was established with a restricted diet followed by a high-fat diet, and the changes of general status and body weight were observed. The levels of fasting blood glucose (FBG), fasting insulin (FINS), triglyceride (TG), and total cholesterol (TC) were measured in 6 rats in each group at the end of the 4th and 8th week, respectively. The homeostasis model assessment of insulin resistance index (HOMA-IR) was calculated, and the insulin sensitivity and body composition changes of CUG rats were evaluated. The successfully modeled rats were assigned into 6 groups: normal control, model, high-, medium-, and low-dose Gegen Qinliantang (2.5, 5, 10 g·kg-1), and pioglitazone (3.125 mg·kg-1). The rats were administrated with corresponding drugs by gavage for 6 weeks, and the normal control group and model group were administrated with the same amount of normal saline. During the experiment period, the changes of body weight were recorded, and the FBG, FINS, HOMA-IR, TG, and TC were determined at the end of the experiment. Hematoxylin-eosin (HE) staining was employed to observe the pathological changes of skeletal muscle in rats. The levels of reactive oxygen species (ROS) and malondialdehyde (MDA) in the skeletal muscle were measured strictly according to the manuals of the reagent kits. Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) was performed to measure the mRNA levels of silencing information regulator 1 (SIRT1), peroxisome proliferator-activated receptor-gamma coactivator1α (PGC1α), and nuclear respiratory factor 1 (Nrf1) in the skeletal muscle. Western blot and immunohistochemistry were employed to assess the expression of SIRT1, PGC1α, and Nrf1 in the skeletal muscle. ResultCompared with the normal control group, the model group presented elevated levels of FBG, FINS, TG, and TC (P<0.05, P<0.01), increased HOMA-IR (P<0.01), increased diameter of muscle fibers and adipocytes between muscle cells in the skeletal muscle, rising levels of ROS and MDA in the skeletal muscle (P<0.01), and down-regulated mRNA and protein levels of SIRT1, PGC1α, and Nrf1 (P<0.05, P<0.01). Compared with the model group, Gegen Qinliantang (especially the medium and high doses) and pioglitazone decreased the body weight, FINS, HOMA-IR, and TG (P<0.05, P<0.01) and reduced interstitial components such as intermuscular fat in the skeletal muscles and the diameter of muscle fibers. Furthermore, the drugs lowerd the levels of ROS and MDA (P<0.05, P<0.01) and up-regulated the mRNA and protein levels of SIRT1, PGC1α, and Nrf1 (P<0.05, P<0.01) in the skeletal muscle. ConclusionGegen Qinliantang can ameliorate the glucose and lipid metabolism disorders and insulin resistance in CUG rats by regulating the SIRT1/PGC1α/Nrf1 signaling pathway.

8.
Indian J Physiol Pharmacol ; 2023 Jun; 67(2): 78-91
Article | IMSEAR | ID: sea-223981

ABSTRACT

Objectives: Proper cardiac function is greatly dependent on adequate supply and metabolism of energy substrates. Environmental pollutants exposure including plasticizers can trigger adverse cardiac metabolic events. This study was designed to investigate the ameliorative effect of rutin (Rt) on dysregulated cardiac energy metabolism in plasticizer-exposed rats. Materials and Methods: Forty-two rats were randomised into seven groups (n = 6): Control (0.1% dimethyl sulfoxide), bisphenol A (BPA, 25 mg/kg, p.o), dibutyl phthalate (DBP, 25 mg/kg, p.o), BPA + Rt 25 mg/kg, Rt 50 mg/kg, DBP + Rt (25 mg/kg, Rt 50 mg/kg), BPA + DBP and BPA + DBP + Rt, daily for 21 days. Results: BPA and DBP exposure increased plasma glucose, reduced insulin, and increased plasma and cardiac free fatty-acid. Cardiac glucose-6-phosphate level, hexokinase and pyruvate dehydrogenase activities increased in DBP while BPA reduced these variables. Cardiac glucose transporter-4 expression was reduced in BPA group, while cardiac peroxisome proliferator-activated receptor-alpha (PPAR?) and AMP-activated protein kinase (AMPK) expression increased in BPA and DBP-treated rats. However, Rt administration prevents impaired cardiac bioenergetics and glucometabolic regulation. Conclusion: Summarily, Rt improves BPA and DBP-impaired cardiac bioenergetics through PPAR? and AMPK modulation.

9.
Indian J Physiol Pharmacol ; 2023 Mar; 67(1): 15-20
Article | IMSEAR | ID: sea-223972

ABSTRACT

Objectives: Diabetic dyslipidaemia (DD) is characterised by hypertriglyceridaemia and elevated or normal levels of low-density lipoprotein cholesterol and decreased levels of high-density lipoprotein cholesterol with Type 2 diabetes mellitus. Statins and anti-diabetic medication are coprescribed for optimal control. Materials and Methods: The objective of the study was to compare the safety and efficacy of Saroglitazar 4-mg and Fenofibrate 200 mg in combination with low dose Atorvastatin (10 mg) in patients with DD. Run-in period of 4 weeks for life-style and diet modification followed by 12 weeks of treatment with saroglitazar or fenofibrate and low dose of atorvastatin was followed. Primary outcome of this study was an absolute change in serum triglyceride level at baseline and end of treatment period (12 weeks). Secondary outcome was changed from baseline lipid profile, fasting blood glucose and glycosylated haemoglobin (HbA1c) at the end of treatment period. Safety assessment was also done during the duration of study. Results: Forty patients of DD were randomly divided into two groups. One group received Saroglitazar 4 mg along with Atorvastatin 10 mg. Patients in second group received Fenofibrate 200 mg along with Atorvastatin 10 mg. Improvement in deranged lipid levels in both the groups was observed and this difference in improvement statistically was not found to be significant. We also observed that Saroglitazar significantly improves glycaemic profile by decreasing fasting blood sugar levels and HbA1c (P = 0.01, P < 0.01). Adverse events reported during this study were mild and none of the patients reported serious adverse events. Conclusion: Saroglitazar could be a potential drug to control both hyperglycaemia and dyslipidaemia in patients with DD.

10.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 47-55, 2023.
Article in Chinese | WPRIM | ID: wpr-996809

ABSTRACT

ObjectiveTo investigate the mechanism of icariin in ameliorating efferocytosis dysfunction and inflammatory response of alveolar macrophages induced by cigarette smoke extract via the peroxisome proliferator-activated receptor gamma (PPARγ) signaling pathway. MethodThe untreated rat alveolar macrophages (NR8383) were taken as the blank group. The NR8383 cells treated with 10% cigarette smoke extract were divided into model, low-, medium-, and high-dose (10, 20, 40 μmol·L-1) icariin, PPARγ inhibitor, and PPARγ inhibitor + low-, medium-, and high-dose icariin groups. Alamar blue colorimetry was employed to examine the proliferation and toxicity of icariin on NR8383 cells. The efferocytosis rate of NR8383 cells was detected by flow cytometry. Enzyme-linked immunosorbent assay was employed to measure the levels of tumor necrosis factor-alpha (TNF-α), transforming growth factor-β1 (TGF-β1), and milk fat globule-epidermal growth factor 8 (MFG-E8). Western blot and Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) were employed to determine the protein and mRNA levels, respectively, of PPARγ, CD36, and RAS-related C3 botulinum toxin substrate 1 (Rac1). ResultThe efferocytosis dysfunction model of NR8383 was established with the cigarette smoke extract. Compared with the blank control group, the model group showed decreased efferocytosis rate (P<0.05), elevated TNF-α level (P<0.05), lowered TGF-β1 and MFG-E8 levels (P<0.01), and down-regulated mRNA and protein levels of PPARγ, CD36, and Rac1 (P<0.05, P<0.01). Compared with the model group, the treatment with icariin increased the efferocytosis rate (P<0.05, P<0.01), lowered the TNF-α level (P<0.01), elevated TGF-β1 and MFG-E8 levels (P<0.05), and up-regulated the protein and mRNA levels of PPARγ, CD36, and Rac1 (P<0.05, P<0.01). Compared with icariin alone, PPARγ inhibitor + icariin decreased the efferocytosis rate (P<0.05) and down-regulated the protein and mRNA levels of PPARγ (P<0.05, P<0.01). In addition, PPARγ inhibitor + low-dose icariin down-regulated the protein level of CD36 (P<0.01) and PPARγ inhibitor + low-/medium-dose icariin up-regulated the protein level of Rac1 (P<0.05). ConclusionIcariin ameliorates the cigarette smoke extract-induced efferocytosis dysfunction of alveolar macrophage by regulating the PPARγ signaling pathway and cytoskeletal structure rearrangement.

11.
Chinese Journal of Dermatology ; (12): 365-368, 2023.
Article in Chinese | WPRIM | ID: wpr-994474

ABSTRACT

Peroxisome proliferator-activated receptors (PPARs) are widely involved in lipid metabolism, glucose metabolism, cell growth and differentiation, and inflammation in the human body. PPARγ agonists can inhibit skin inflammatory response, protect epidermal barrier function, and repair skin injury. This review summarizes various roles of PPARγ in skin biology, and discusses its function in skin diseases, such as psoriasis and skin tumors.

12.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 1-8, 2023.
Article in Chinese | WPRIM | ID: wpr-988174

ABSTRACT

ObjectiveTo observe the effect of modified Gegen Qinliantang on the expression levels of proteins related to the farnesoid X receptor/small heterodimer partner/peroxisome proliferator-activated receptor α (FXR/SHP/PPARα) signaling pathway in the liver tissue of db/db model mice with type 2 diabetes mellitus (T2DM) and explore the underlying mechanism of action of modified Gegen Qinliantang. MethodThirty db/db mice were randomly divided into model group, metformin group (0.2 g·kg-1), and high-, medium-, and low-dose modified Gegen Qinliantang groups (31.9, 19.1, 6.4 g·kg-1), with 6 mice in each group. An additional six m/m mice were assigned to the blank group. Respective drugs were administered via oral gavage for 12 weeks. Mouse body weight, fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels were measured. Oil red O staining was used to observe hepatic lipid accumulation and periodic acid-schiff (PAS) staining was used to assess hepatic glycogen deposition. Ammonium ferric sulfate staining was used to observe cholesterol deposition in intestinal tissues. Western blot was employed to detect the expression of FXR, cholesterol 7α-hydroxylase (CYP7A1), SHP, and PPARα proteins in liver tissues, and enzyme-linked immunosorbent assay (ELISA) was used to measure serum free fatty acid (FFA) levels. ResultAt the end of the treatment, compared with the blank group, the model group exhibited significant increases in mouse body weight, FBG, FFA, TC, TG, and LDL-C levels (P<0.01), along with significant hepatic lipid droplets, reduced hepatic glycogen, noticeable cholesterol accumulation in intestinal tissues, significantly decreased expression of FXR, SHP, PPARα proteins, and significantly increased expression of CYP7A1 protein in liver tissues (P<0.01). Compared with the model group, the metformin group and the high- and medium-dose modified Gegen Qinliantang groups demonstrated significant reductions in mouse body weight, FBG, FFA, TC, TG, LDL-C levels (P<0.05, P<0.01), significant increases in HDL-C levels (P<0.05, P<0.01), decreased hepatic lipid accumulation, increased hepatic glycogen, reduced intestinal cholesterol accumulation, significantly increased expression of FXR, SHP, PPARα proteins, and significantly decreased expression of CYP7A1 protein in liver tissues (P<0.01). ConclusionModified Gegen Qinliantang may regulate the FXR/SHP/PPARα signaling pathway to suppress FFA levels and improve lipid metabolism in T2DM mice.

13.
Acta Anatomica Sinica ; (6): 269-275, 2023.
Article in Chinese | WPRIM | ID: wpr-1015216

ABSTRACT

[Abstract] Objective To establish an inflammation model by stimulating BV2 microglia by lipopolysaccharide, and to explore the regulation effect of ginsenoside Rg1 on inflammation by activating peroxisome proliferator activated receptor γ(PPARγ) receptor protein. Methods BV2 microglia were randomly divided into control group, model group, ginsenoside Rg1 group, rosiglitazone group and GW9662 group. The control group did not do any treatment, the model group was treated with 1 mg/ L lipopolysaccharide, and the other groups were treated with lipopolysaccharide added with 0. 4 mmol/ L ginsenoside Rg1, 10 μmol/ L rosiglitazone or 10 μmol/ L respectively. GW9662. The proliferation of BV2 microglia in each group was detected by CCK-8 method; PPAR-γ, phospho-NF-κB p65 (p-NF-κB p65), induced expression of inducible nitric oxide synthase(iNOS) and human arginase 1(ARG-1) proteins. ELISA was used to detect the inflammatory factors interleukin-1β(IL-1β), interleukin-6(IL-6), interleukin-8(IL-8) and the content of tumor necrosis factor-α (TNF-α). Results Compared with the control group, the cell proliferation rate in the model group was significantly increased, and the contents of IL-1β, IL-6, IL-8 and TNF-α increased significantly. The result of immunofluorescence and Western blotting showed that iNOS and p-NF-κB p65 increased significantly, and the positive expressions of PPARγ and ARG-1 decreased significantly(both P<0. 01). The expression level of TNF-α decreased, the positive expressions of iNOS and p-NF-κB p65 decreased significantly, and the positive expressions of PPARγ and ARG-1 increased significantly(all P<0. 01). Conclusion Ginsenoside Rg1 inhibits the inflammatory response of BV2 microglia after lipopolysaccharide stimulation, and its mechanism may be related to the regulation of PPARγ/ NF-κB pathway to promote the M2-type polarization of microglia.

14.
Chinese Journal of Clinical Pharmacology and Therapeutics ; (12): 796-808, 2023.
Article in Chinese | WPRIM | ID: wpr-1014626

ABSTRACT

Cholestatic liver disease is a common disease that causes bile flow dysfunction due to various reasons. The etiology of cholestatic liver disease is complexed, and therapeutic drugs are extremely limited. To date, ursodeoxycholic acid is the only FDA-approved drug for treating primary biliary cirrhosis, whereas its efficacy is limited to early stage of the disease, therefore novel drugs are urgently needed. Nuclear receptors become therapeutic hotspot target in cholestasis since these receptors play a key role in regulating bile acid homeostasis. Peroxisome proliferator-activated receptor (PPAR) is an important nuclear receptor involved in regulating multiple mechanisms of cholestasis in vivo. It can improve intrahepatic cholestasis by inhibiting bile acid synthesis, reducing bile acid toxicity, affecting the expression of bile acid metabolic enzymes and transporters, and can play an anti-inflammatory, anti-oxidation and anti-fibrosis role. A number of studies have shown that PPAR agonists represented by fibrates alone or in combination can improve liver function indexes, inflammatory factors and fibrosis markers in patients with cholestasis. This review analyzes and summarizes the lastest advances in the molecular mechanism of PPAR as a therapeutic target for cholestasis and drug treatment in development or have been used in clinical.

15.
Chinese Pharmacological Bulletin ; (12): 57-65, 2023.
Article in Chinese | WPRIM | ID: wpr-1013878

ABSTRACT

Aim To investigate the effects of acid sphingomyelinase(ASMase)on high-fat induced nonalcoholic fatty liver disease in mice and its regulation of PPARα- PGC-1α pathway. Methods ASMase knockout mice based on C57BL/6 background were constructed. Closed group heterozygotes were obtained through hybridized with wild-type mice(ASMase+/-),together with the littermate WT mice were prepared for NAFLD model in this study. The experiment was divided into four groups:WT+Chow:the WT mice were fed with normal diet for 12 weeks; WT+HFD:the WT mice were fed with high-fat diet for 12 weeks; ASMase+/-+Chow:the ASMase+/- mice were fed with normal diet for 12 weeks; ASMase+/- +HFD:the ASMase+/- mice were fed with high fat diet for 12 weeks. Biochemical method was used to detect serum TC,TG and liver TC,TG contents and liver function such as ALT and AST. Oil red staining,HE staining,Masson staining and Sirius red staining were performed to detect liver lipid accumulation,hepatocyte morphology and liver fibrosis. AmplexTM red sphingomyelinase kit was applied to detect ASMase activity. Western blot was performed to detect protein expressions of ASMase,PPARα,PGC-1α and CPT1. Results WT+HFD group displayed hypercholesterolemia and liver dysfunction. Levels of liver triglyceride(TG)were significantly higher than those in WT+Chow group(P<0.05 or P<0.01). Meanwhile,the hepatocytes showed marked steatosis,balloon-like changes,and fibrosis. Protein expression and activity of ASMase in liver increased significantly(P<0.01 or P<0.001),whereas CPT1,PPARα and PGC-1α expressions were not statistically significant compared with matched control group. Heterozygously ASMase-deficient mice reduced the elevated liver TG induced by HFD,as well as improving balloon-like changes and liver fibrosis. Furthermore,the expressions of PPARα,PGC-1α and CPT1 were up-regulated in ASMase+/- +HFD mice compared with WT+Chow group.Conclusions ASMase promotes hepatic steatosis and fibrosis,which may be related to its inhibition of PPARα-PGC-1α pathway.

16.
Acta Pharmaceutica Sinica B ; (6): 3756-3769, 2023.
Article in English | WPRIM | ID: wpr-1011147

ABSTRACT

Myocardial dysfunction is the most serious complication of sepsis. Sepsis-induced myocardial dysfunction (SMD) is often associated with gastrointestinal dysfunction, but its pathophysiological significance remains unclear. The present study found that patients with SMD had higher plasma gastrin concentrations than those without SMD. In mice, knockdown of the gastrin receptor, cholecystokinin B receptor (Cckbr), aggravated lipopolysaccharide (LPS)-induced cardiac dysfunction and increased inflammation in the heart, whereas the intravenous administration of gastrin ameliorated SMD and cardiac injury. Macrophage infiltration plays a significant role in SMD because depletion of macrophages by the intravenous injection of clodronate liposomes, 48 h prior to LPS administration, alleviated LPS-induced cardiac injury in Cckbr-deficient mice. The intravenous injection of bone marrow macrophages (BMMs) overexpressing Cckbr reduced LPS-induced myocardial dysfunction. Furthermore, gastrin treatment inhibited toll-like receptor 4 (TLR4) expression through the peroxisome proliferator-activated receptor α (PPAR-α) signaling pathway in BMMs. Thus, our findings provide insights into the mechanism of the protective role of gastrin/CCKBR in SMD, which could be used to develop new treatment modalities for SMD.

17.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 203-213, 2023.
Article in Chinese | WPRIM | ID: wpr-964961

ABSTRACT

ObjectiveTo observe the effect of salvianolate on the protein expressions of adenosine monophosphate (AMP)-activated protein kinase (AMPK), silent information regulator 1 (SIRT1) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), autophagy and apoptosis in kidney tissue of rats with membranous nephropathy (MN), and to explore its possible molecular mechanism against MN. MethodEighty male SD rats were randomly divided into normal group, model group, benazepril hydrochloride group (10 mg·kg-1), and salvianolate low-, medium-, and high-dose groups (16.7, 33.3 and 66.7 mg·kg-1). The rats were modeled by injection of cationized bovine serum albumin (C-BSA) into the tail vein. After successful modeling, rats in the administration groups were given corresponding doses of drugs for 4 consecutive weeks, and then 24-hour urine, serum and kidney tissue were collected for the detection of 24-hour urinary protein (UTP), blood urea nitrogen (BUN), serum creatinine (SCr), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), C reactive protein (CRP), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and malondialdehyde (MDA). The pathological changes of kidneys were observed by light microscope, electron microscope and immunofluorescence. Western blot was used to detect the protein expressions of phospho-AMPK (p-AMPK), AMPK, phospho-SIRT1 (p-SIRT1), SIRT1 and PGC-1α in rat kidney tissue. The protein expressions of autophagy-specific gene (Beclin-1), microtubule-associated protein 1 light chain 3 (LC3) Ⅱ, ubiquitin-binding protein (p62), B cell lymphoma (Bcl-2), Bcl-2-associated X (Bax), and cysteine aspartic protease-7 (Caspase-7) in rat kidney tissue were determined by immunohistochemistry (IHC). ResultCompared with the conditions in the normal group, the levels of UTP, IL-6, TNF-α, CRP and MDA in the model group were increased (P<0.05) while the levels of SOD and GSH-Px were decreased (P<0.05), and there was no difference in BUN and SCr. Compared with the model group, the administration groups had lowered UTP, IL-6, TNF-α, CRP and MDA (P<0.05) while elevated SOD and GSH-Px (P<0.05). It could be seen from hematoxylin and eosin (HE) staining, Masson staining, immunofluorescence and electron microscopy that the pathological damage of rat kidney tissue in the model group was significant, but after treatment with benazepril hydrochloride and salvianolate, the pathological damage of kidney cells was gradually improved. The expressions of p-AMPK/AMPK, p-SIRT1/SIRT1, PGC-1α, Bcl-2, Beclin-1 and LC3Ⅱ in rat kidney in the model group were lower than those in the normal group (P<0.05) while the expressions of Bax, Caspase-7 and p62 were higher (P<0.05). Compared with the model group, benazepril hydrochloride group and salvianolate groups had an up-regulation in the expressions of p-AMPK/AMPK, p-SIRT1/SIRT1, PGC-1α, Bcl-2, Beclin-1 and LC3Ⅱ in the kidney (P<0.05) while a down-regulation in the expressions of Bax, Caspase-7 and p62 (P<0.05). ConclusionThe protective effect of salvianolate on the kidneys of MN rats may be related to the activation of AMPK/SIRT1/PGC-1α signaling pathway, the up-regulation of autophagy and the reduction of apoptosis.

18.
China Pharmacy ; (12): 327-332, 2023.
Article in Chinese | WPRIM | ID: wpr-961667

ABSTRACT

OBJECTIVE To investigate the improvement effects and possible mechanism of Phyllanthus emblica water extracts on lipid metabolism disorder and insulin resistance (IR) in diabetic model rats. METHODS IR model of male SD rats was established and randomly divided into model group, positive control group, P. emblica water extracts high-dose, medium-dose and low-dose groups, and another blank group was set up, with 10 rats in each group. P. emblica water extracts high-dose, medium- dose and low-dose groups were given P. emblica water extract diluent at the doses of 800, 400 and 200 mg/kg respectively; positive control group was given pioglitazone solution 2.7 mg/kg; blank group and model group were given the same volume of normal saline, by intragastrical administration, once a day, for consecutive 4 weeks. The general state of rats was observed, and the body mass and the levels of serum lipid metabolism indexes [triacylglycerol (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C)] were measured; fasting insulin of serum (FINS), insulin resistance index (IRI) and insulin sensitivity index (ISI) were measured and calculated by enzyme-linked immunosorbent assay (ELISA). The pathological morphology of liver tissue was observed by hematoxylin-eosin staining; the expression of glycogen in the liver was observed by periodic acid-Schiff staining, and the staining area was calculated; the protein expressions of peroxisome proliferator-activated receptor γ (PPARγ), nuclear factor κB(NF-κB) and AMP-activated protein kinase (AMPK) were detected by Western blot. RESULTS Compared with blank group, the rats in the model group had obvious symptoms of polydipsia, polyphagia and polyuria, and the serum levels of TC, TG, LDL-C, FINS and IRI were significantly increased (P<0.05), while ISI was significantly reduced (P< 0.05); the structure of hepatic lobule was obviously disordered, the liver cells were deformed and enlarged, and there were many lipid deposits and fat vacuoles; PAS staining area of glycogen was significantly reduced(P<0.05); the protein expression levels of PPARγ and p-AMPK were significantly decreased (P<0.05), while the protein expression level of NF-κB was significantly increased (P<0.05). Compared with model group, the mental state of rats, liver histopathological morphology and glycogen expression were improved significantly in P. emblica water extracts high-dose and medium-dose groups; the levels of the above indicators were significantly reversed(P<0.05). CONCLUSIONS P. emblica water extracts may improve glucose and lipid metabolism disorders, liver function and IR in IR model rats, and regulate IR by activating the PPARγ/AMPK/NF-κB signaling pathway.

19.
Chinese Acupuncture & Moxibustion ; (12): 783-792, 2023.
Article in Chinese | WPRIM | ID: wpr-980796

ABSTRACT

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.


Subject(s)
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
20.
China Pharmacy ; (12): 1847-1852, 2023.
Article in Chinese | WPRIM | ID: wpr-979935

ABSTRACT

OBJECTIVE To investigate the effects of β-sitosterol on the function of rheumatoid arthritis (RA) fibroblastic synoviocytes MH7A cells and its mechanism. METHODS Network pharmacology was adopted to screen the targets of β-sitosterol and the targets for the treatment of RA. After the intersection of them, topological analysis was performed to find the most critical target in the treatment of RA. MH7A cells were treated with different concentrations (0, 5, 10, 20, 40 μmol/L) of β-sitosterol, and CCK-8 was used to assay cell viability for screening the optimal concentration of β-sitosterol. MH7A cells were induced by 10 ng/mL TNF-α in vitro and treated with β-sitosterol (the optimum concentration). CCK-8 and EdU were used to detect the ability of cell proliferation. Scratch experiment and Transwell invasion assay were used to analyze cell migration and invasion. The levels of interleukin-1β (IL-1β) and IL-6 in cell supernatant were detected by enzyme-linked immunosorbent assay (ELISA). The mRNA and protein expressions of peroxisome proliferator-activated receptor α (PPARα) were measured by qRT-PCR and Western blot, respectively. The siRNA targeting PPARα was transfected into MH7A cells, and the effects of β-sitosterol on cell proliferation, migration, invasion, the secretion of inflammatory factors and the expression of PPARα after PPARα knockdown were detected by the above experimental methods. RESULTS PPARα was the most critical target of β-sitosterol in the treatment of RA. The optimal concentration of β-sitosterol was 20 μmol/L. Compared with model group, β-sitosterol decreased the viability of MH7A cells, and the number of proliferating cells also decreased significantly (P<0.05); the cell migration rate and the number of cell invasion decreased significantly (P<0.05). The levels of IL-1β and IL-6 were also significantly decreased (P<0.05), and the mRNA 15 and protein expression levels of PPARα were significantly increased (P<0.05). Compared with negative control small interfering RNA group, after PPARα knockdown, the cell viability increased by about 35.6% (P<0.05), the number of cell proliferation, the cell migration rate and the number of cell invasion increased significantly (P<0.05), and the levels of IL-1β and IL-6 also increased significantly (P<0.05). CONCLUSIONS β-sitosterol could effectively inhibit the proliferation, migration, invasion and secretion of inflammatory factors in MH7A cells, the mechanism of which may be associated with activating PPARα pathway.

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