PGC-1α activator ZLN005 promotes maturation of cardiomyocytes derived from human embryonic stem cells.

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have great potential in biomedical applications. However, the immature state of cardiomyocytes obtained using existing protocols limits the application of hPSC-CMs. Unlike adult cardiac myocytes, hPSC-CMs generate ATP through an immature metabolic pathway-aerobic glycolysis, instead of mitochondrial oxidative phosphorylation (OXPHOS). Hence, metabolic switching is critical for functional maturation in hPSC-CMs. Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) is a key regulator of mitochondrial biogenesis and metabolism, which may help promote cardiac maturation during development. In this study, we investigated the effects of PGC-1α and its activator ZLN005 on the maturation of human embryonic stem cell-derived cardiomyocyte (hESC-CM). hESC-CMs were generated using a chemically defined differentiation protocol and supplemented with either ZLN005 or DMSO (control) on differentiating days 10 to 12. Biological assays were then performed around day 30. ZLN005 treatment upregulated the expressions of PGC-1α and mitochondrial function-related genes in hESC-CMs and induced more mature energy metabolism compared with the control group. In addition, ZLN005 treatment increased cell sarcomere length, improved cell calcium handling, and enhanced intercellular connectivity. These findings support an effective approach to promote hESC-CM maturation, which is critical for the application of hESC-CM in disease modeling, drug screening, and engineering cardiac tissue.

Effect of cholestasis and NeuroAid treatment on the expression of Bax, Bcl-2, Pgc-1α and Tfam genes involved in apoptosis and mitochondrial biogenesis in the striatum of male rats.

Cholestasis means impaired bile synthesis or secretion. In fact, it is a bile flow reduction following Bile Duct Ligation (BDL). Cholestasis has a main role in necrosis and apoptosis. Apoptosis is a form of programmed cell death that has intrinsic and extrinsic pathways. The intrinsic pathway is mediated by Bcl-2 (B cell lymphoma-2) proteins which integrate death and survival signals. Bcl-2 has anti-apoptotic and Bax has pro-apoptotic effects. Also, striatum is one of the brain regions that has high expressions of Bcl-2 proteins. Moreover, Tfam and Pgc-1α are involved in mitochondrial biogenesis. On the other hand, NeuroAid, is a drug that has neuroprotective and anti-apoptosis effects. In this study, using quantitative PCR, we measured the expression of all these genes in the striatum of male rats following BDL and NeuroAid administration. Results showed, BDL increased the expression of Bax and Tfam and decreased the expression of Bcl-2. NeuroAid restored the effect of BDL on the expression of Bax, while did not alter the effect of BDL on Bcl-2. In addition, it increased the expression of Tfam that was previously elevated by BDL and raised the expression of Tfam in normal rats. Both BDL and NeuroAid, had no effect on Pgc-1α. In conclusion, cholestasis increased the expression of Bax and decreased the expression of Bcl-2, and this effect may have related to enhanced susceptibility of mitochondrial pathways following oxidative stress. Tfam expression was increased following cholestasis and this effect may have related to cellular compensatory mechanisms against high accumulation of free radicals or mitochondrial biogenesis failure. Furthermore, NeuroAid may play a role against apoptosis and can be used to increase mitochondrial biogenesis.

AMP Kinase Activation is Selectively Disrupted in the Ventral Midbrain of Mice Deficient in Parkin or PINK1 Expression.

Parkinson's disease (PD) is a prevalent neurodegenerative movement disorder that is characterized pathologically by the progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) of the midbrain. Despite intensive research, the etiology of PD remains poorly understood. Interestingly, recent studies have implicated neuronal energy dysregulation as one of the key perpetrators of the disease. Supporting this, we have recently demonstrated that pharmacological or genetic activation of AMP kinase (AMPK), a master regulator of cellular energy homeostasis, rescues the pathological phenotypes of Drosophila models of PD. However, little is known about the role of AMPK in the mammalian brain. As an initial attempt to clarify this, we examined the expression of AMPK in rodent brains and found that phospho-AMPK (pAMPK) is disproportionately distributed in the adult mouse brain, being high in the ventral midbrain where the SN resides and relatively lower in regions such as the cortex-reflecting perhaps the unique energy demands of midbrain DA neurons. Importantly, the physiologically higher level of midbrain pAMPK is significantly reduced in aged mice and also in Parkin-deficient mice; the loss of function of which in humans causes recessive Parkinsonism. Not surprisingly, the expression of PGC-1α, a downstream target of AMPK activity, and a key regulator of mitochondrial biogenesis, mirrors the expression pattern of pAMPK. Similar observations were made with PINK1-deficient mice. Finally, we showed that metformin administration restores the level of midbrain pAMPK and PGC-1α expression in Parkin-deficient mice. Taken together, our results suggest that the disruption of AMPK-PGC-1α axis in the brains of individuals with Parkin or PINK1 mutations may be a precipitating factor of PD, and that pharmacological AMPK activation may represent a neuroprotective strategy for the disease.

The protective effects of compatibility of Aconiti Lateralis Radix Praeparata and Zingiberis Rhizoma on rats with heart failure by enhancing mitochondrial biogenesis via Sirt1/PGC-1α pathway.

Aconiti Lateralis Radix Praeparata ("Fuzi" in Chinese) in combination with Zingiberis Rhizoma ("Ganjiang" in Chinese) is commonly applied for the treatment of heart failure for thousands of years in China. However, its therapeutic mechanism is still poorly defined. This study aimed to investigate whether the compatibility of Fuzi and Ganjiang can protect rats with acute heart failure by enhancing mitochondrial biogenesis via Sirt1/PGC-1α signaling pathway. Hemodynamic parameters, including heart rate and left ventricular maximal rate of pressure rise and decline, were recorded in rats with acute heart failure induced by Propafenone hydrochloride. The serum levels of cardiac enzymes, including creatine kinase, lactate dehydrogenase, brain natriuretic peptide and cardiac troponin T, were also determined. The gene and protein levels of Sirtuin 1 (Sirt1), peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) and their downstream transcription factors were measured as well. The results indicated that Fuzi-Ganjiang herbal couple provided more significant benefits by restoring the left ventricular function and cardiac enzyme activities in comparison with their single use. Moreover, this herbal couple possessed a significant cardio-protection by increasing both gene and protein levels of Sirt1 and PGC-1α. In conclusion, the compatibility of Fuzi and Ganjiang had better therapeutic effect than their single use against failing heart, and the underlying mechanisms were partially through increasing mitochondrial biogenesis via Sirt1/PGC-1α pathway.

Sugar Composition Analysis of Fuzi Polysaccharides by HPLC-MSn and Their Protective Effects on Schwann Cells Exposed to High Glucose.

Fuzi has been used to treat diabetic complications for many years in china. In a previous study, we have shown that Fuzi aqueous extract can attenuate Diabetic peripheral neuropathy (DPN) in rats and protect Schwann cells from injury. Thus, the protective effect of Fuzi polysaccharides (FPS) on high glucose-induced SCs and the preliminary mechanism were investigated. Firstly, the FPS were obtained and their monose composition was analyzed by the combination of pre-column derivatization and high performance liquid chromatography coupled with electrospray ionization multi-tandem mass spectrometry (HPLC/ESI-MSn). The results witnessed the efficiency of this method and seven monosaccharides were tentatively identified, among which fucose was first reported. Simultaneously, m/z 215 can be considered as diagnostic ions to confirm the number of monosaccharides. Next, high glucose-induced SC model was applied and divided into model group, treated group of FPS, normal and osmotic control group. After treatment for 48 h, the data showed FPS could significantly decrease the intracellular ROS and apoptosis, which were determined by the corresponding fluorescent probes. Then, the expression of oxidative stress-related proteins in SCs were measured by Western blot. Furthermore, the protein tests found that FPS markedly up-regulated superoxide dismutase (SOD), catalase (CAT) and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) protein level, but down-regulated NADPH oxidase-1 (Nox1) protein level. Moreover, FPS could also increase AMP-activated protein kinase (AMPK) activation significantly. Hence, we preliminary deduced that AMPK-PGC-1α pathway may play an important role in the protective effect of FPS against high glucose-induced cell damage.

Aqueous Extract of Paris polyphylla (AEPP) Inhibits Ovarian Cancer via Suppression of Peroxisome Proliferator-Activated Receptor-Gamma Coactivator (PGC)-1alpha.

Chemotherapy, a major approach was used in carcinoma treatment, always involves the development of drug resistance as well as side-effects that affect the quality of patients' lives. An association between epithelial-mesenchymal transition (EMT) and chemotherapy resistance was established recently. We demonstrate in this paper that the aqueous extract of Paris polyphylla (AEPP)-a traditional Chinese medicine-can be used in various cancer types for suppression of carcinogenesis. We evaluated the suppressions of EMT and mitochondrial activity by AEPP treatment in a high-glucose (HG) induced-human ovarian carcinoma cell line (OVCAR-3 cells). The mitochondrial morphology was investigated using MitoTracker Deep Red FM staining. Our results indicated that AEPP reduced the viability of OVCAR-3 cells considerably through induction of apoptosis. However, this inhibitory potential of AEPP was attenuated by HG induction in OVCAR-3 cells. The levels of estrogen-related receptor (ERR)-alpha activator and peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1alpha were elevated by HG induction, but were suppressed by AEPP treatment. Down-regulations of cell survival and EMT were oberved in OVCAR-3 cells through suppression of PGC-1alpha by AEPP treatment. These results were confirmed through PGC-1alpha knockdown and overexpression in OVCAR-3 cells. Thus, AEPP can be beneficial for treating ovarian cancer and has potential for development of an integrative cancer therapy against ovarian cancer proliferation, metastasis, and migration.

The combination of Artemisia princeps Pamp, Leonurus japonicas Houtt, and Gardenia jasminoides Ellis fruit attenuates the exacerbation of energy, lipid, and glucose by increasing hepatic PGC-1α expression in estrogen-deficient rats.

BACKGROUND: Artemisia princeps Pamp (APP), Leonurus japonicas Houtt (LJH), and Gardenia jasminoides Ellis fruit (GJE) have been traditionally used in East Asia to treat women's diseases related to reproductive system. They may attenuate the deterioration of energy, lipid, glucose and bone metabolism by estrogen deficiency. The present study explored the combination of APP, LJH, and GJE to overcome the symptoms of estrogen deficiency and the mechanism was explored. METHODS: Ovariectomized (OVX) rats were divided into five groups and fed high-fat diets supplemented with 2 % dextrin (control), 2 % APP, 2 % APP + LJH (15:5), APP + LJH + GJE (10:5:5) or 17ß-estradiol (30 µg/kg bw/day) for 8 weeks. After 8 weeks of their consumption, energy, lipid, glucose and bone metabolisms were investigated and hepatic insulin signaling and fatty acid metabolism were determined. RESULTS: APP + LJH + GJE, but not APP itself, improved energy metabolism and attenuated a decrease in energy expenditure by the same amount as estrogen. Moreover, APP + LJH + GJE reduced visceral fat and intramuscular fat and increased lean body mass measured by DEXA by as much as the positive-control. APP itself suppressed increased LDL cholesterol and triglyceride levels in OVX rats and APP + LJH + GJE alleviated dyslipidemia in OVX rats. Overnight-fasted serum insulin levels and HOMA-IR were reduced in the descending order of APP, APP + LJH, APP + LJH + GJE, positive-control in OVX rats. APP and APP + LJH elevated insulin secretion in the 1st part of OGTT to decrease serum glucose levels while APP + LJH + GJE reduced serum glucose levels without increasing serum insulin levels during OGTT. APP + LJH + GJE decreased insulin resistance during ITT in OVX rats more than the positive-control. The APP + LJH + GJE group exhibited increased hepatic peroxisomal proliferator-activated receptor-γ coactivator-1α expression, which increased the number of genes involved in fatty acid oxidation and decreased fatty acid synthesis. Hepatic insulin signaling (pAkt and pGSK-1ß) was also potentiated to reduce phosphoenolpyruvate carboxykinase proteins. CONCLUSION: The combination of APP + LJH + GJE attenuated various menopausal symptoms in OVX rats. Thus, it may have potential as a therapeutic agent for the treatment of postmenopausal symptoms.