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.
ABSTRACT
Objective:To observe the effects of Da Chaihutang on Cyclic adenosine monophosphate （cAMP）-response element binding protein （CREB）/peroxisome proliferator-activated receptor-gamma coactivator-1 alpha （PGC-1<italic>α</italic>） pathway in nutritionally obese rats and the protective mechanism on liver mitochondria. Method:A total of 120 8-week-old male SD rats were randomly divided into a control group （<italic>n</italic>=20） and an experimental group （<italic>n</italic>=100）. The rats in the control group were fed on a normal diet， while those in the experimental group were administered with a high-fat feed. Successfully modeled rats were randomly divided into a model group， a positive drug （metformin） group， and low-， medium- and high-dose Da Chaihutang groups （4.25， 8.5， and 17 g∙kg<sup>-1</sup>， respectively）， with 20 rats in each group. After treatment with Da Chaihutang， the body weight， Lee's index， liver mitochondrial membrane potential and mitochondrial ultrastructure， PGC-1<italic>α </italic>expression and CREB phosphorylation of each group were measured and compared. Result:Compared with the control group， the model group showed increased body weight and Lee's index （<italic>P</italic><0.01）， whereas decreased mitochondrial membrane potential， PGC-1<italic>α</italic> expression， and CREB phosphorylation level （<italic>P</italic><0.01）. As compared with the model group， Da Chaihutang significantly reduced the body weight and Lee's index of obese rats （<italic>P</italic><0.05， <italic>P</italic><0.01）， enhanced liver mitochondrial membrane potential （<italic>P</italic><0.05， <italic>P</italic><0.01） to protect the integrity of mitochondrial structure， up-regulated PGC-1<italic>α</italic> expression and promoted CREB phosphorylation （<italic>P</italic><0.05， <italic>P</italic><0.01）. Conclusion:Da Chaihutang protects the structure and function of mitochondria and inhibits weight gain in obese rats by activating the CREB/PGC-1<italic>α</italic> pathway.
ABSTRACT
ObjectiveTo investigate the association of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PPARGC1A) rs8192678 single nucleotide polymorphism (SNP) with the risk of nonalcoholic fatty liver disease (NAFLD) and the influence of PPARGC1A rs8192678 SNP on NAFLD-related biochemical parameters. MethodsA total of 119 NAFLD patients who attended Qingdao Municipal Hospital Affiliated to Qingdao University from December 2017 to December 2018 were enrolled as NAFLD group, and 213 individuals who underwent physical examination during the same period of time were enrolled as control group. Clinical data and blood samples were collected from all subjects to measure related biochemical parameters and detect PPARGC1A rs8192678 SNP. The chi-square test was used to determine whether the genotype distribution of samples was in accordance with the Hardy-Weinberg equilibrium. The t-test or the Wilcoxon rank-sum test was used for comparison of continuous data between two groups, and the chi-square test was used for comparison of categorical data between two groups. A binary logistic regression analysis was used to investigate the risk factors for NAFLD. ResultsThere were no significant differences in the genotype and allele frequencies of PPARGC1A rs8192678 between the NAFLD group and the control group (χ2=0.011 and 0.015, P=0.918 and 0.904). The binary logistic regression analysis showed that CT genotype of PPARGC1A rs8192678 was not a risk factor for NAFLD (odds ratio=0.951, 95% confidence interval: 0.368-2.457, P=0.918). In the NAFLD group, the patients carrying CT genotype had a significantly higher level of gamma-glutamyl transpeptidase (GGT) than those carrying CC genotype (Z=-2.331, P=0.020). ConclusionPPARGC1A rs8192678 SNP does not increase the risk of NAFLD, while NAFLD patients carrying CT genotype tend to have a higher serum level of GGT.
ABSTRACT
Cardiovascular disease is currently the number one killer of human health. Studies have shown that peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is a key factor in physiological processes such as energy metabolism and oxidative stress, which also involved in regulating mitochondrial biosynthesis. PGC-1α is closely related to the occurrence and development of atherosclerosis, coronary heart disease, atrial fibrillation, cardiomyopathy, myocardial hypertrophy, heart failure and other cardiovascular diseases. This article briefly describes the research progress of PGC-1α in cardiovascular diseases.
ABSTRACT
<p><b>Background</b>Shensong Yangxin Capsule (SSYX), traditional Chinese medicine, has been used to treat arrhythmias, angina, cardiac remodeling, cardiac fibrosis, and so on, but its effect on cardiac energy metabolism is still not clear. The objective of this study was to investigate the effects of SSYX on myocardium energy metabolism in angiotensin (Ang) II-induced cardiac hypertrophy.</p><p><b>Methods</b>We used 2 μl (10 mol/L) AngII to treat neonatal rat cardiomyocytes (NRCMs) for 48 h. Myocardial α-actinin staining showed that the myocardial cell volume increased. Expression of the cardiac hypertrophic marker-brain natriuretic peptide (BNP) messenger RNA (mRNA) also increased by real-time polymerase chain reaction (PCR). Therefore, it can be assumed that the model of hypertrophic cardiomyocytes was successfully constructed. Then, NRCMs were treated with 1 μl of different concentrations of SSYX (0.25, 0.5, and 1.0 μg/ml) for another 24 h. To explore the time-depend effect of SSYX on energy metabolism, 0.5 μg/ml SSYX was added into cells for 0, 6, 12, 24, and 48 h. Mitochondria was assessed by MitoTracker staining and confocal microscopy. mRNA and protein expression of mitochondrial biogenesis-related genes - Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), energy balance key factor - adenosine monophosphate-activated protein kinase (AMPK), fatty acids oxidation factor - carnitine palmitoyltransferase-1 (CPT-1), and glucose oxidation factor - glucose transporter- 4 (GLUT-4) were measured by PCR and Western blotting analysis.</p><p><b>Results</b>With the increase in the concentration of SSYX (from 0.25 to 1.0 μg/ml), an increased mitochondrial density in AngII-induced cardiomyocytes was found compared to that of those treated with AngII only (0.25 μg/ml, 18.3300 ± 0.8895 vs. 24.4900 ± 0.9041, t = 10.240, P < 0.0001; 0.5 μg/ml, 18.3300 ± 0.8895 vs. 25.9800 ± 0.8187, t = 12.710, P < 0.0001; and 1.0 μg/ml, 18.3300 ± 0.8895 vs. 24.2900 ± 1.3120, t = 9.902, P < 0.0001; n = 5 per dosage group). SSYX also increased the mRNA and protein expression of PGC-1α (0.25 μg/ml, 0.8892 ± 0.0848 vs. 1.0970 ± 0.0994, t = 4.319, P = 0.0013; 0.5 μg/ml, 0.8892 ± 0.0848 vs. 1.2330 ± 0.0564, t = 7.150, P < 0.0001; and 1.0 μg/ml, 0.8892 ± 0.0848 vs. 1.1640 ± 0.0755, t = 5.720, P < 0.0001; n = 5 per dosage group), AMPK (0.25 μg/ml, 0.8872 ± 0.0779 vs. 1.1500 ± 0.0507, t = 7.239, P < 0.0001; 0.5 μg/ml, 0.8872 ± 0.0779 vs. 1.2280 ± 0.0623, t = 9.379, P < 0.0001; and 1.0 μg/ml, 0.8872 ± 0.0779 vs. 1.3020 ± 0.0450, t = 11.400, P < 0.0001; n = 5 per dosage group), CPT-1 (1.0 μg/ml, 0.7348 ± 0.0594 vs. 0.9880 ± 0.0851, t = 4.994, P = 0.0007, n = 5), and GLUT-4 (0.5 μg/ml, 1.5640 ± 0.0599 vs. 1.7720 ± 0.0660, t = 3.783, P = 0.0117; 1.0 μg/ml, 1.5640 ± 0.0599 vs. 2.0490 ± 0.1280, t = 8.808, P < 0.0001; n = 5 per dosage group). The effect became more obvious with the increasing concentration of SSYX. When 0.5 μg/ml SSYX was added into cells for 0, 6, 12, 24, and 48 h, the expression of AMPK (6 h, 14.6100 ± 0.6205 vs. 16.5200 ± 0.7450, t = 3.456, P = 0.0250; 12 h, 14.6100 ± 0.6205 vs. 18.3200 ± 0.9965, t = 6.720, P < 0.0001; 24 h, 14.6100 ± 0.6205 vs. 21.8800 ± 0.8208, t = 13.160, P < 0.0001; and 48 h, 14.6100 ± 0.6205 vs. 23.7400 ± 1.0970, t = 16.530, P < 0.0001; n = 5 per dosage group), PGC-1α (12 h, 11.4700 ± 0.7252 vs. 16.9000 ± 1.0150, t = 7.910, P < 0.0001; 24 h, 11.4700 ± 0.7252 vs. 20.8800 ± 1.2340, t = 13.710, P < 0.0001; and 48 h, 11.4700 ± 0.7252 vs. 22.0300 ± 1.4180, t = 15.390; n = 5 per dosage group), CPT-1 (24 h, 15.1600 ± 1.0960 vs. 18.5800 ± 0.9049, t = 6.048, P < 0.0001, n = 5), and GLUT-4 (6 h, 10.2100 ± 0.9485 vs. 12.9700 ± 0.8221, t = 4.763, P = 0.0012; 12 h, 10.2100 ± 0.9485 vs. 16.9100 ± 0.8481, t = 11.590, P < 0.0001; 24 h, 10.2100 ± 0.9485 vs. 19.0900 ± 0.9797, t = 15.360, P < 0.0001; and 48 h, 10.2100 ± 0.9485 vs. 14.1900 ± 0.9611, t = 6.877, P < 0.0001; n = 5 per dosage group) mRNA and protein increased gradually with the prolongation of drug action time.</p><p><b>Conclusions</b>SSYX could increase myocardial energy metabolism in AngII-induced cardiac hypertrophy. Therefore, SSYX might be considered to be an alternative therapeutic remedy for myocardial hypertrophy.</p>