Functional alpha 1 protease inhibitor produced by a human hepatoma cell line

Emerging Therapeutic Strategies for Parkinson’s Disease and Future Prospects: A 2021 Update

Parkinson’s disease (PD) is a neurodegenerative disorder pathologically distinguished by degeneration of dopaminergic neurons in the substantia nigra pars compacta. Muscle rigidity, tremor, and bradykinesia are all clinical motor hallmarks of PD. Several pathways have been implicated in PD etiology, including mitochondrial dysfunction, impaired protein clearance, and neuroinflammation, but how these factors interact remains incompletely understood. Although many breakthroughs in PD therapy have been accomplished, there is currently no cure for PD, only trials to alleviate the related motor symptoms. To reduce or stop the clinical progression and mobility impairment, a disease-modifying approach that can directly target the etiology rather than offering symptomatic alleviation remains a major unmet clinical need in the management of PD. In this review, we briefly introduce current treatments and pathophysiology of PD. In addition, we address the novel innovative therapeutic targets for PD therapy, including α-synuclein, autophagy, neurodegeneration, neuroinflammation, and others. Several immunomodulatory approaches and stem cell research currently in clinical trials with PD patients are also discussed. Moreover, preclinical studies and clinical trials evaluating the efficacy of novel and repurposed therapeutic agents and their pragmatic applications with encouraging outcomes are summarized. Finally, molecular biomarkers under active investigation are presented as potentially valuable tools for early PD diagnosis.

The endocannabinoid system in the adipose organ

The endocannabinoid system is found in most, if not all, mammalian organs and is involved in a variety of physiological functions, ranging from the control of synaptic plasticity in the brain to the modulation of smooth muscle motility in the gastrointestinal tract. This signaling complex consists of G protein-coupled cannabinoid receptors, endogenous ligands for those receptors (endocannabinoids) and enzymes/transporters responsible for the formation and deactivation of these ligands. There are two subtypes of cannabinoid receptors, CB₁ and CB₂, and two major endocannabinoids, arachidonoylethanolamide (anandamide) and 2-arachidonoyl-sn-glycerol (2-AG), which are produced upon demand through cleavage of distinct phospholipid precursors. All molecular components of the endocannabinoid system are represented in the adipose organ, where endocannabinoid signals are thought to regulate critical homeostatic processes, including adipogenesis, lipogenesis and thermogenesis. Importantly, obesity was found to be associated with excess endocannabinoid activity in visceral fat depots, and the therapeutic potential of normalizing such activity by blocking CB₁ receptors has been the focus of substantial preclinical and clinical research. Results have been mixed thus far, mostly owing to the emergence of psychiatric side effects rooted in the protective functions served by brain endocannabinoids in mood and affect regulation. Further studies about the roles played by the endocannabinoid system in the adipose organ will offer new insights into the pathogenesis of obesity and might help identify new ways to leverage this signaling complex for therapeutic benefit.

Intestinal farnesoid X receptor signaling controls hepatic fatty acid oxidation

In addition to maintaining bile acid, cholesterol and glucose homeostasis, farnesoid X receptor (FXR) also regulates fatty acid β-oxidation (FAO). To explore the different roles of hepatic and intestinal FXR in liver FAO, FAO-associated metabolites, including acylcarnitines and fatty acids, and FXR target gene mRNAs were profiled using an integrated metabolomic and transcriptomic analysis in control (Fxrfl/fl), liver-specific Fxr-null (FxrΔHep) and intestine-specific Fxr-null (FxrΔIE) mice, treated either with the FXR agonist obeticholic acid (OCA) or vehicle (VEH). Activation of FXR by OCA treatment significantly increased fatty acyl-CoA hydrolysis (Acot1) and decreased FAO-associated mRNAs in Fxrfl/fl mice, resulting in reduced levels of total acylcarnitines and relative accumulation of long/medium chain acylcarnitines and fatty acids in liver. FxrΔHep mice responded to OCA treatment in a manner similar to Fxrfl/fl mice while FxrΔIE mice responded differently, thus illustrating that intestinal FXR plays a critical role in the regulation of hepatic FAO. A significant negative-correlation between intestinal FXR-FGF15 and hepatic CREB-PGC1A pathways was observed after both VEH and OCA treatment, suggesting that OCA-induced activation of the intestinal FXR-FGF15 axis downregulates hepatic PGC1α signaling via inactivation of hepatic CREB, thus repressing FAO. This mechanism was confirmed in experiments based on human recombinant FGF19 treatment and intestinal Fgf15-null mice. This study revealed an important role for the intestinal FXR-FGF15 pathway in hepatic FAO repression.

Activation of PGC-1α via isoliquiritigenin-induced downregulation of miR-138-5p alleviates nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), a metabolic disease, has received wide attention worldwide. However, there is no approved effective drug for NAFLD treatment. In the study, H&E and Oil Red O staining were employed to detect liver histopathological changes and the accumulation of lipid droplets. Quantitative real-time PCR, Western blot, bioinformatics, luciferase assay, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to further elucidate the mechanism of isoliquiritigenin (ISL) against NAFLD. The results showed that ISL significantly reduced the liver-to-body weight ratios and biochemical index. And the staining results showed that ISL remarkedly ameliorated liver histopathological changes of NAFLD. Furthermore, ISL significantly increased the levels of PPARα, CPT1α, and ACADS, which were involved in lipid metabolism, and inhibited the ROS, TNF-α, IL-1β, and IL-6 expression by activating PGC-1α. Bioinformatics and luciferase assay analysis confirmed that miR-138-5p might bind to PGC-1α mRNA in NAFLD. Importantly, the expression of miR-138-5p was increased in the NAFLD, which was significantly decreased by ISL. In addition, the miR-138-5p inhibitor also promoted lipid metabolism and inhibited inflammatory response in NAFLD via PGC-1α activation. The above results demonstrate that ISL alleviates NAFLD through modulating miR-138-5p/PGC-1α-mediated lipid metabolism and inflammatory reaction in vivo and in vitro.

Combined Phyllostachys pubescens and Scutellaria baicalensis Prevent High-Fat Diet-Induced Obesity via Upregulating Thermogenesis and Energy Expenditure by UCP1 in Male C57BL/6J Mice

This study examined the anti-obesity effects of a Phyllostachys pubescens (leaf) and Scutellaria baicalensis root mixture (BS21), and its underlying mechanisms of action, in high-fat diet (HFD)-induced obese mice. Mice were fed a HFD with BS21 (100, 200, or 400 mg/kg) for 9 weeks. BS21 reduced body weight, white adipose tissue (WAT) and liver weights, liver lipid accumulation, and adipocyte size. Additionally, BS21 reduced serum concentrations of non-esterified fatty acid, triglyceride, glucose, lactate dehydrogenase, low-density lipoprotein cholesterol, total cholesterol, leptin, and insulin growth factor 1, but elevated the adiponectin concentrations. Furthermore, BS21 suppressed the mRNA levels of lipogenesis-related proteins, such as peroxisome proliferator–activated receptor (PPAR) γ, SREBP-1c, C/EBP-α, fatty acid synthase, and leptin, but increased the mRNA gene expression of lipolysis-related proteins, such as PPAR-α, uncoupling protein (UCP) 2, adiponectin, and CPT1b, in WAT. In addition, BS21 increased the cold-stimulated adaptive thermogenesis and UCP1 protein expression with AMPK activation in adipose tissue. Furthermore, BS21 increased the WAT and mRNA expression of energy metabolism-related proteins SIRT1, PGC-1α, and FNDC5/irisin in the quadriceps femoris muscle. These results suggest that BS21 exerts anti-obesity and antihyperlipidemic activities in HFD-induced obese mice by increasing the thermogenesis and energy expenditure, and regulating lipid metabolism. Therefore, BS21 could be useful for preventing and treating obesity and its related metabolic diseases.

Oolong tea extract alleviates weight gain in high-fat diet-induced obese rats by regulating lipid metabolism and modulating gut microbiota

Obesity is a serious global health issue and has become particularly prominent during the current COVID-19 pandemic. Tea is a traditional beverage in Asia and has been shown to provide...

Gynostemma pentaphyllum extract and its active component gypenoside L improve the exercise performance of treadmill-trained mice

BACKGROUND/OBJECTIVES

The effectiveness of natural compounds in improving athletic ability has attracted attention in both sports and research. Gynostemma pentaphyllum (Thunb.) leaves are used to make traditional herbal medicines in Asia. The active components of G. pentaphyllum, dammarane saponins, or gypenosides, possess a range of biological activities. On the other hand, the anti-fatigue effects from G. pentaphyllum extract (GPE) and its effective compound, gypenoside L (GL), remain to be determined.

MATERIALS/METHODS

This study examined the effects of GPE on fatigue and exercise performance in ICR mice. GPE was administered orally to mice for 6 weeks, with or without treadmill training. The biochemical analysis in serum, glycogen content, mRNA, and protein expressions of the liver and muscle were analyzed.

RESULTS

The ExGPE (exercise with 300 mg/kg body weight/day of GPE) mice decreased the fat mass percentage significantly compared to the ExC mice, while the ExGPE showed the greatest lean mass percentage compared to the ExC group. The administration of GPE improved the exercise endurance and capacity in treadmill-trained mice, increased glucose and triglycerides, and decreased the serum creatine kinase and lactate levels after intensive exercise. The muscle glycogen levels were higher in the ExGPE group than the ExC group. GPE increased the level of mitochondrial biogenesis by enhancing the phosphorylation of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein and the mRNA expression of nuclear respiratory factor 1, mitochondrial DNA, peroxisome proliferator-activated receptor-δ, superoxide dismutase 2, and by decreasing the lactate dehydrogenase B level in the soleus muscle (SOL). GPE also improved PGC-1α activation in the SOL significantly through AMPK/p38 phosphorylation.

CONCLUSIONS

These results showed that GPE supplementation enhances exercise performance and has anti-fatigue activity. In addition, the underlying molecular mechanism was elucidated. Therefore, GPE is a promising candidate for developing functional foods and enhancing the exercise capacity and anti-fatigue activity.

Genetic characteristics of competitive swimmers: a review

A successful swimming performance is a multi-factorial accomplishment, resulting from a complex interaction of physical, biomechanical, physiological and psychological factors, all of which are strongly affected by the special medium of water as well as by genetic factors. The nature of competitive swimming is unique, as most of the competitive events last less than four minutes. Yet training regimens have an endurance nature (many hours and many kilometres of swimming every day), which makes it impossible to classify swimming by definitions of aerobic-type or anaerobic-type events, as in track and field sports. Therefore, genetic variants associated with swimming performance are not necessarily related to metabolic pathways, but rather to blood lactate transport (MCT1), muscle functioning (IGF1 axis), muscle damage (IL6) and others. The current paper reviews the main findings on the leading 12 genetic polymorphisms (located in the ACE, ACTN3, AMPD1, BDKRB2, IGF1, IL6, MCT1, MSTN, NOS3, PPARA, PPARGC1A, and VEGFR2 genes) related to swimming performance, while taking into consideration the unique environment of this sport.

Recombinant Human Growth Hormone Inhibits Lipotoxicity, Oxidative Stress, and Apoptosis in a Mouse Model of Diabetic Cardiomyopathy

Recombinant human growth hormone (rhGH), widely used in clinical studies, exerts protective effects against cardiac damage. Here, we investigated the effects and mechanisms underlying the effects of rhGH on cardiac functions in db/db mice. C57BL/6J and db/db mice were subjected to rhGH treatment. Metabolic parameters, cardiac function and morphology, oxidative stress, lipid metabolism, and apoptosis were evaluated 16 weeks after rhGH treatment. Although rhGH did not significantly affect fasting blood glucose levels in db/db mice, it protected against diabetic cardiomyopathy, by improving cardiac function and reducing oxidative stress in the heart. In addition, rhGH treatment exhibited anti-apoptotic effects in the heart of db/db mice. The rhGH treatment, besides inhibiting oxidative stress and apoptosis, ameliorated cardiac dysfunction by inhibiting lipotoxicity in mice with type 2 diabetes. These findings suggest that rhGH is a promising therapeutic agent for diabetic cardiomyopathy.

Preventing Oxidative Stress in the Liver: An Opportunity for GLP-1 and/or PASK

The liver’s high metabolic activity and detoxification functions generate reactive oxygen species, mainly through oxidative phosphorylation in the mitochondria of hepatocytes. In contrast, it also has a potent antioxidant mechanism for counterbalancing the oxidant’s effect and relieving oxidative stress. PAS kinase (PASK) is a serine/threonine kinase containing an N-terminal Per-Arnt-Sim (PAS) domain, able to detect redox state. During fasting/feeding changes, PASK regulates the expression and activation of critical liver proteins involved in carbohydrate and lipid metabolism and mitochondrial biogenesis. Interestingly, the functional inactivation of PASK prevents the development of a high-fat diet (HFD)-induced obesity and diabetes. In addition, PASK deficiency alters the activity of other nutrient sensors, such as the AMP-activated protein kinase (AMPK) and the mammalian target of rapamycin (mTOR). In addition to the expression and subcellular localization of nicotinamide-dependent histone deacetylases (SIRTs). This review focuses on the relationship between oxidative stress, PASK, and other nutrient sensors, updating the limited knowledge on the role of PASK in the antioxidant response. We also comment on glucagon-like peptide 1 (GLP-1) and its collaboration with PASK in preventing the damage associated with hepatic oxidative stress. The current knowledge would suggest that PASK inhibition and/or exendin-4 treatment, especially under fasting conditions, could ameliorate disorders associated with excess oxidative stress.

Studies on the effects of hypothermia combined with hypoxia on rat skeletal muscle and lipid metabolism based on AMPK/PGC1α pathway

Aim

To explore the effects of hypothermia and hypoxia on rat skeletal muscle and lipid metabolism.

Method

Forty male rats were randomly divided into blank group, low-temperature group, hypoxia group, and hypothermia combined with hypoxia group. The body weight of the rats was monitored. The changes of Irisin were detected by ELISA, and LDL, HDL, TC, and TG levels in serum were detected by blood biochemistry. Western blot was used to detect the changes of lipid metabolism-related proteins. CCK8 was used to verify the effect of AMPK/PGC1α on the proliferation of rat skeletal muscle cells.

Result

In the case of cold stimulation and hypoxia, the weight of the rats decreased significantly, and the levels of LDL, HDL, TC, and TG in the serum were abnormal. The activity of fatty acid metabolism factors Irisin, UCP-1, and FABP4 is down-regulated by hypothermia and hypoxia. The activity of fat metabolism-related enzymes, ATGL, HSL, and MGL increased under hypothermia and low oxygen conditions. Hypothermia and hypoxia affected the morphology of skeletal muscle, and AMPK/PGC-1α can regulate the proliferation of skeletal muscle cells.

Conclusion

Hypothermia and hypoxia can reduce the body weight of rats, and affect the structure of skeletal muscle to promote lipid metabolism through AMPK/PGC-1α signaling pathway.

Modulatory role of the endocannabinoidome in the pathophysiology of the gastrointestinal tract

Originating from Eastern Asia, the plant Cannabis sativa has been used for centuries as a medicinal treatment. The unwanted psychotropic effects of one of its major components, Δ⁹-tetrahydrocannabinol, discouraged its therapeutic employment until, recently, the discovery of cannabinoids receptors and their endogenous ligands endocannabinoids reignited the interest. The endocannabinoid system has lately been found to play an important role in the maintenance of human health, both centrally and peripherally. However, the initial idea of the endocannabinoid system structure has been quickly understood to be too simplistic and, as new receptors, mediators, and enzymes have been discovered to participate in a complex relationship, the new, more comprehensive term "expanded endocannabinoid system" or "endocannabinoidome", has taken over. The discovery of other endocannabinoid-like receptors, such as the G protein-coupled receptor 119 and G protein-coupled receptor 55, has opened the way to the development of potential therapeutic targets for the treatment of various metabolic disorders. In addition, recent findings have also provided evidence suggesting the potential therapeutic link between the endocannabinoidome and various inflammatory-based gut diseases, such as inflammatory bowel disease and cancer. This review will provide an introduction to the endocannabinoidome, focusing on its modulatory role in the gastrointestinal tract and on the interest generated by the link between gut microbiota, the endocannabinoid system and metabolic diseases such as inflammatory bowel disease, type-2 diabetes and obesity. In addition, we will look at the potential novel aspects and benefits of drugs targeting the endocannabinoid system.

Cisd2 slows down liver aging and attenuates age-related metabolic dysfunction in male mice

The liver plays a pivotal role in mammalian aging. However, the mechanisms underlying liver aging remain unclear. Cisd2 is a pro‐longevity gene in mice. Cisd2 mediates lifespan and healthspan via regulation of calcium homeostasis and mitochondrial functioning. Intriguingly, the protein level of Cisd2 is significantly decreased by about 50% in the livers of old male mice. This down‐regulation of Cisd2 may result in the aging liver exhibiting non‐alcoholic fatty liver disease (NAFLD) phenotype. Here, we use Cisd2 transgenic mice to investigate whether maintaining Cisd2 protein at a persistently high level is able to slow down liver aging. Our study identifies four major discoveries. Firstly, that Cisd2 expression attenuates age‐related dysregulation of lipid metabolism and other pathological abnormalities. Secondly, revealed by RNA sequencing analysis, the livers of old male mice undergo extensive transcriptomic alterations, and these are associated with steatosis, hepatitis, fibrosis, and xenobiotic detoxification. Intriguingly, a youthful transcriptomic profile, like that of young 3‐month‐old mice, was found in old Cisd2 transgenic male mice at 26 months old. Thirdly, Cisd2 suppresses the age‐associated dysregulation of various transcription regulators (Nrf2, IL‐6, and Hnf4a), which keeps the transcriptional network in a normal pattern. Finally, a high level of Cisd2 protein protects the liver from oxidative stress, and this is associated with a reduction in mitochondrial DNA deletions. These findings demonstrate that Cisd2 is a promising target for the development of therapeutic agents that, by bringing about an effective enhancement of Cisd2 expression, will slow down liver aging.

Altered Cardiac Energetics and Mitochondrial Dysfunction in Hypertrophic Cardiomyopathy

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is a complex disease partly explained by the effects of individual gene variants on sarcomeric protein biomechanics. At the cellular level, HCM mutations most commonly enhance force production, leading to higher energy demands. Despite significant advances in elucidating sarcomeric structure-function relationships, there is still much to be learned about the mechanisms that link altered cardiac energetics to HCM phenotypes. In this work, we test the hypothesis that changes in cardiac energetics represent a common pathophysiologic pathway in HCM.

METHODS

We performed a comprehensive multiomics profile of the molecular (transcripts, metabolites, and complex lipids), ultrastructural, and functional components of HCM energetics using myocardial samples from 27 HCM patients and 13 normal controls (donor hearts).

RESULTS

Integrated omics analysis revealed alterations in a wide array of biochemical pathways with major dysregulation in fatty acid metabolism, reduction of acylcarnitines, and accumulation of free fatty acids. HCM hearts showed evidence of global energetic decompensation manifested by a decrease in high energy phosphate metabolites (ATP, ADP, and phosphocreatine) and a reduction in mitochondrial genes involved in creatine kinase and ATP synthesis. Accompanying these metabolic derangements, electron microscopy showed an increased fraction of severely damaged mitochondria with reduced cristae density, coinciding with reduced citrate synthase activity and mitochondrial oxidative respiration. These mitochondrial abnormalities were associated with elevated reactive oxygen species and reduced antioxidant defenses. However, despite significant mitochondrial injury, HCM hearts failed to upregulate mitophagic clearance.

CONCLUSIONS

Overall, our findings suggest that perturbed metabolic signaling and mitochondrial dysfunction are common pathogenic mechanisms in patients with HCM. These results highlight potential new drug targets for attenuation of the clinical disease through improving metabolic function and reducing mitochondrial injury.

Sex-specific genetic regulation of adipose mitochondria and metabolic syndrome by Ndufv2

We have previously suggested a central role for mitochondria in the observed sex differences in metabolic traits. However, the mechanisms by which sex differences affect adipose mitochondrial function and metabolic syndrome are unclear. Here we show that in both mice and humans, adipose mitochondrial functions are elevated in females and are strongly associated with adiposity, insulin resistance and plasma lipids. Using a panel of diverse inbred strains of mice, we identify a genetic locus on mouse chromosome 17 that controls mitochondrial mass and function in adipose tissue in a sex- and tissue-specific manner. This locus contains Ndufv2 and regulates the expression of at least 89 mitochondrial genes in females, including oxidative phosphorylation genes and those related to mitochondrial DNA content. Overexpression studies indicate that Ndufv2 mediates these effects by regulating supercomplex assembly and elevating mitochondrial reactive oxygen species production, which generates a signal that increases mitochondrial biogenesis.

Shen Qi Li Xin formula improves chronic heart failure through balancing mitochondrial fission and fusion via upregulation of PGC-1α

BACKGROUND

Our previous study proved that Shen Qi Li Xin formula (SQLXF) improved the heart function of chronic heart failure (CHF) patients, while the action mechanism remains unclear.

METHODS

H&E staining and TUNEL staining were performed to measure myocardial damages. Western blot was used to examine the expression of proteins. Moreover, CCK-8 assay and flow cytometry were used to measure cell viability and cell apoptosis, respectively. Concentrations of ATP and ROS in cells, and mitochondrial membrane potential (MMP) were detected to estimate oxidative stress.

RESULTS

In vivo, we found that SQLXF improved cardiac hemodynamic parameters, reduced LDH, CK-MB and BNP production, and attenuated myocardial damages in CHF rats. Besides, SQLXF promoted mitochondrial fusion-related proteins expression and inhibited fission-related proteins expression in CHF rats and oxygen glucose deprivation/reoxygenation (OGD/R)-induced cardiac myocytes (CMs). In vitro, our data show that certain dose of SQLXF inhibited OGD/R-induced CMs apoptosis, cell viability decreasing and oxidative stress.

CONCLUSION

Overall, certain dose of SQLXF could effectively improve the cardiac function of CHF rats through inhibition of CMs apoptosis via balancing mitochondrial fission and fusion. Our data proved a novel action mechanism of SQLXF in CHF improvement, and provided a reference for clinical.

Anti-Sarcopenic Obesity Effects of Lonicera caerulea Extract in High-Fat Diet-Fed Mice

Sarcopenic obesity is a combination of sarcopenia and obesity. Although several herbal extracts showed improvement on sarcopenia and obesity, respectively, there are few studies on sarcopenic obesity. Lonicera caerulea (honeysuckle berry, HB) can ameliorate metabolic disorders including obesity. However, its effects on sarcopenic obesity have not been reported yet. Thus, the aim of this study was to investigate whether HB extract might have any beneficial effects on sarcopenic obesity in high-fat diet-induced mice. Forty-eight mice were classified into six groups and treated for eight weeks: (1) NC, normal diet control; (2) HC, high-fat diet control; (3) PC, high-fat diet with orlistat; (4) HB100, high-fat diet with HB extract at 100 mg/kg; (5) HB200, high-fat diet with HB extract at 200 mg/kg; and (6) HB400, high-fat diet with HB extract at 400 mg/kg. Body weight, fat accumulation, muscle mass, muscle strength, and mRNA expression of muscle atrophy were monitored. Compared with the HC group, HB administration showed anti-obesity properties. It reduced body weight gain and modulated serum biochemical parameters and tissue antioxidant enzymes. HB also increased muscle strength and muscle mass of hind legs. In addition, it decreased mRNA expression levels of Atrogin1 and MuRF1 as markers of muscle atrophy but increased PGC1α and SIRT1 as markers of muscle growth. These results suggest that HB might be effective in preventing sarcopenia associated with obesity.

Changes in mitochondrial biogenesis and fatty liver indicators in rat following continuous and high intensity interval training

BACKGROUND

Oxidative stress and mitochondrial dysfunction can be tracked down in most liver diseases like non-alcoholic fatty liver disease (NAFLD). The most recommended preventative method is lifestyle modification, especially exercise. The aim of this study was the investigation of changes in the indexes of mitochondrial biogenesis and fatty liver indicators in rat following continuous and high intensity interval training.

METHODS

Thirty healthy male rats were divided into three control (C=10), Continuous swimming training (CT=10) and High intensity interval swimming training groups (HIIT=10). The training groups performed their specific exercises 5 days a week for 8 weeks. 24 h after the last training session in order to prepare the serum, a blood sample was taken from the left ventricle of the rats. In addition, liver tissue was extracted and the SIRT3, PGC-1α, GSH:GSSG, MDA, LDL, HDL, LDL:HDL, TG, TC, AST, ALT and FBS variables were measured by ELISA and analysis of blood biochemistry.

RESULTS

Continuous training (CT) increased the levels of PGC-1α, SIRT3 and significantly reduced LDL, LDL:HDL, TG and FBS (P<0.05) levels. High-intensity interval training (HIIT) caused a significant increase in SIRT3 and a significant decrease in FBS (P<0.05) levels.

CONCLUSIONS

Adaptations resulting from further aerobic exercise can increase mitochondrial biogenesis factors such as PGC-1α and SIRT3 in hepatocytes, improve this process in hepatocytes, and ultimately improve the fatty liver markers. Therefore, CT may be more effective than HIIT in preventing fatty liver disease.

A Review of miRNAs as Biomarkers and Effect of Dietary Modulation in Obesity Associated Cognitive Decline and Neurodegenerative Disorders

There has been a progressive increase in the prevalence of obesity and its comorbidities such as type 2 diabetes and cardiovascular diseases worldwide. Recent studies have suggested that the crosstalk between adipose tissue and central nervous system (CNS), through cellular mediators and signaling pathways, may causally link obesity with cognitive decline and give rise to neurodegenerative disorders. Several mechanisms have been proposed in obesity, including inflammation, oxidative stress, insulin resistance, altered lipid and cholesterol homeostasis, which may result in neuroinflammation, altered brain insulin signaling, amyloid-beta (Aβ) deposition and neuronal cell death. Since obesity is associated with functional and morphological alterations in the adipose tissues, the resulting peripheral immune response augments the development and progression of cognitive decline and increases susceptibility of neurodegenerative disorders, such as Alzheimer's Disease (AD) and Parkinson's Disease (PD). Studies have also elucidated an important role of high fat diet in the exacerbation of these clinical conditions. However, the underlying factors that propel and sustain this obesity associated cognitive decline and neurodegeneration, remains highly elusive. Moreover, the mechanisms linking these phenomena are not well-understood. The cumulative line of evidence have demonstrated an important role of microRNAs (miRNAs), a class of small non-coding RNAs that regulate gene expression and transcriptional changes, as biomarkers of pathophysiological conditions. Despite the lack of utility in current clinical practices, miRNAs have been shown to be highly specific and sensitive to the clinical condition being studied. Based on these observations, this review aims to assess the role of several miRNAs and aim to elucidate underlying mechanisms that link obesity with cognitive decline and neurodegenerative disorders. Furthermore, this review will also provide evidence for the effect of dietary modulation which can potentially ameliorate cognitive decline and neurodegenerative diseases associated with obesity.

The Same Metabolic Response to FGF21 Administration in Male and Female Obese Mice Is Accompanied by Sex-Specific Changes in Adipose Tissue Gene Expression

The preference for high-calorie foods depends on sex and contributes to obesity development. Fibroblast growth factor 21 (FGF21) beneficially affects taste preferences and obesity, but its action has mainly been studied in males. The aim of this study was to compare the effects of FGF21 on food preferences and glucose and lipid metabolism in C57Bl/6J male and female mice with diet-induced obesity. Mice were injected with FGF21 or vehicle for 7 days. Body weight, choice between standard (SD) and high-fat (HFD) diets, blood parameters, and gene expression in white (WAT) and brown (BAT) adipose tissues, liver, muscles, and the hypothalamus were assessed. Compared to males, females had a greater preference for HFD; less WAT; lower levels of cholesterol, glucose, and insulin; and higher expression of Fgf21, Insr, Ppara, Pgc1, Acca and Accb in the liver and Dio2 in BAT. FGF21 administration decreased adiposity; blood levels of cholesterol, glucose, and insulin; hypothalamic Agrp expression, increased SD intake, decreased HFD intake independently of sex, and increased WAT expression of Pparg, Lpl and Lipe only in females. Thus, FGF21 administration beneficially affected mice of both sexes despite obesity-associated sex differences in metabolic characteristics, and it induced female-specific activation of gene expression in WAT.

Effects of maternal undernutrition during late pregnancy on the regulatory factors involved in growth and development in ovine fetal perirenal brown adipose tissue

Objective

The experiment was conducted to evaluate the effects of maternal undernutrition during late pregnancy on the expressions of genes involved in growth and development in ovine fetal perirenal brown adipose tissue (BAT).

Methods

Eighteen ewes with singleton fetuses were allocated to three groups at day 90 of pregnancy: restricted group 1 (RG1, 0.33 MJ metabolisable energy [ME]/kg body weight [BW]^0.75/d, n = 6), restricted group 2 (RG2, 0.18 MJ ME/kg BW^0.75/d, n = 6), and a control group (CG, ad libitum, 0.67 MJ ME/kg BW^0.75/d, n = 6). The fetuses were removed at day 140 of pregnancy. All data were analyzed by using the analysis of variance procedure.

Results

The perirenal fat weight (p = 0.0077) and perirenal fat growth rate (p = 0.0074) were reduced in RG2 compared to CG. In fetal perirenal BAT, the protein level of uncoupling protein 1 (UCP1) (p = 0.0001) was lower in RG1 and RG2 compared with CG and UCP1 mRNA expression (p = 0.0265) was decreased in RG2. The protein level of myogenic factor 5 (Myf5) was also decreased in RG2 (p = 0.0001). In addition, mRNA expressions of CyclinA (p = 0.0109), CyclinB (p = 0.0019), CyclinD (p = 0.0015), cyclin-dependent kinase 1 (CDK1) (p = 0.0001), E2F transcription factor 1 (E2F1) (p = 0.0323), E2F4 (p = 0.0101), and E2F5 (p = 0.0018) were lower in RG1 and RG2. There were decreased protein expression of peroxisome proliferator-activated receptor-γ (PPARγ) (p = 0.0043) and mRNA expression of CCAAT/enhancer-binding protein-α (C/EBPα) (p = 0.0307) in RG2 and decreased PPARγ mRNA expression (p = 0.0008) and C/EBPα protein expression (p = 0.0015) in both RG2 and RG1. Furthermore, mRNA expression of bone morphogenetic protein 4 (BMP4) (p = 0.0083) and BMP7 (p = 0.0330) decreased in RG2 and peroxisome proliferator-activated receptor co-activator-1α (PGC-1α) reduced in RG2 and RG1.

Conclusion

Our observations support that repression of regulatory factors promoting differentiation and development results in the inhibition of BAT maturation in fetal perirenal fat during late pregnancy with maternal undernutrition.

Irisin Enhances Angiogenesis of Mesenchymal Stem Cells to Promote Cardiac Function in Myocardial Infarction via PI3k/Akt Activation

Background and Objectives

With the growing incidence of acute myocardial infarction (MI), angiogenesis is vital for cardiac function post-MI. The role of bone marrow mesenchymal stem cells (BMSCs) in angiogenesis has been previously confirmed. Irisin is considered a potential vector for angiogenesis. The objective of the present study was to investigate the potential role of irisin in the angiogenesis of BMSCs.

Methods and Results

In vivo, irisin-treated BMSCs (BMSCs＋irisin) were transplanted into an MI mouse model. On day 28 post-MI, blood vessel markers were detected, and cardiac function and infarct areas of mice were evaluated. In vitro, paracrine effects were assessed by examining tube formation in human umbilical vein endothelial cells (HUVECs) co-cultured with the BMSCs＋irisin supernatant. The scratch wound-healing assay was performed to evaluate HUVEC migration. Western blotting was performed to determine PI3k/Akt pathway activation in the BMSCs＋irisin group. Transplantation of BMSCs＋irisin promoted greater angiogenesis, resulting in better cardiac function in the MI mouse model than in controls. In the BMSC＋irisin group, HUVECs demonstrated enhanced tube formation and migration. Activation of the PI3k/Akt pathway was found to be involved in mediating the role of irisin in the angiogenesis of BMSCs.

Conclusions

In cardiovascular diseases such as MI, irisin administration can enhance angiogenesis of BMSCs and promote cardiac function via the PI3k/Akt pathway, optimizing the therapeutic effect based on BMSCs transplantation.

Benefits of Polyphenols and Methylxanthines from Cocoa Beans on Dietary Metabolic Disorders

Theobroma cacao L. is an ancestral cultivated plant which has been consumed by various populations throughout history. Cocoa beans are the basic material occurring in the most consumed product in the world, namely chocolate. Their composition includes polyphenols, methylxanthines, lipids and other compounds that may vary qualitatively and quantitatively according to criteria such as variety or culture area. Polyphenols and methylxanthines are known as being responsible for many health benefits, particularly by preventing cardiovascular and neurodegenerative diseases. Recent studies emphasized their positive role in dietary metabolic disorders, such as diabetes and weight gain. After a brief presentation of cocoa bean, this review provides an overview of recent research activities highlighting promising strategies which modulated and prevented gastro-intestinal metabolism dysfunctions.

Atractylodes chinensis Water Extract Ameliorates Obesity via Promotion of the SIRT1/AMPK Expression in High-Fat Diet-Induced Obese Mice

Obesity remains a continuing global health concern, as it is associated with an increased risk of many chronic diseases. Atractylodes chinensis Koidz. (Ac) is traditionally used in the treatment of inflammatory diseases, such as arthritis, hepatitis, and gastric ulcers. Despite the diverse pharmacological activities of Ac, scientific evidence for the use of Ac in obesity is still limited. Therefore, the present study aimed to determine the anti-obesity effects of Ac. C57BL/6N mice were divided into five groups as follows: chow diet group (CON), 45% HFD group, HFD + oral administration of orlistat group, and HFD + oral administration of Ac groups. RT-PCR and western blotting were used to examine the expression of molecules relating to obesity progression. Ac-administered mice showed dramatically decreased body weight and weight gain compared to the high-fat diet (HFD)-fed mice. In addition, Ac administration attenuated the protein expression levels of adipogenic transcription factors in the white adipose tissue (WAT) and livers of HFD-fed mice. Furthermore, Ac administration declined the expression levels of lipogenic genes, while enhancing those of the fatty acid oxidation genes in the WAT of HFD-fed mice. Importantly, Ac administration highly upregulated the AMP-activated kinase (AMPK) and sirtuin 1 (SIRT1) expression levels in WAT of the HFD-induced obese mouse model. Our results provide evidence that Ac can effectively ameliorate weight gain and adipose tissue expansion.

TNF promotes M1 polarization through mitochondrial metabolism in injured spinal cord

Macrophages and microglia (M/Ms) in the injured spinal cord maintain a predominantly neurotoxic M1 phenotype that is disadvantageous to repair in the development of spinal cord injury (SCI). It has been reported that tumor necrosis factor (TNF) that polarize M/Ms toward M1 state in various disorders. In this study, we found that ablation of TNF endorsed the beneficial conversion from M1 to M2 phenotype and improved the mitochondrial metabolism in vivo and in vitro. In addition, PGC-1α that accumulates in TNF null mice, a major participant of mitochondrial metabolism, downregulated ROS activity and the expressions of M1-specific mRNA. Moreover, the absence of TNF upgraded the morphology and quantity of damaged mitochondria and rapidly switched to M2 phenotype as compare to administration of N-Acetyl-l-cysteine (NAC). Furthermore, systemic application of TPEN showed that increased ratio of M1 M/Ms. These combined results supporting predominant and prolonged TNF expression that is destructive to recovery after SCI. These results indicated that TNF would have great potential immunomodulatory for the treatment of SCI.

Natural α-Glucosidase and Protein Tyrosine Phosphatase 1B Inhibitors: A Source of Scaffold Molecules for Synthesis of New Multitarget Antidiabetic Drugs

Diabetes mellitus (DM) represents a group of metabolic disorders that leads to acute and long-term serious complications and is considered a worldwide sanitary emergence. Type 2 diabetes (T2D) represents about 90% of all cases of diabetes, and even if several drugs are actually available for its treatment, in the long term, they show limited effectiveness. Most traditional drugs are designed to act on a specific biological target, but the complexity of the current pathologies has demonstrated that molecules hitting more than one target may be safer and more effective. The purpose of this review is to shed light on the natural compounds known as α-glucosidase and Protein Tyrosine Phosphatase 1B (PTP1B) dual-inhibitors that could be used as lead compounds to generate new multitarget antidiabetic drugs for treatment of T2D.

Four-and-a-half LIM domain protein 2 (FHL2) deficiency protects mice from diet-induced obesity and high FHL2 expression marks human obesity

OBJECTIVE

Four-and-a-Half-LIM-domain-protein 2 (FHL2) modulates multiple signal transduction pathways but has not been implicated in obesity or energy metabolism. In humans, methylation and expression of the FHL2 gene increases with age, and high FHL2 expression is associated with increased body weight in humans and mice. This led us to hypothesize that FHL2 is a determinant of diet-induced obesity.

METHODS

FHL2-deficient (FHL2-/-) and wild type male mice were fed a high-fat diet. Metabolic phenotyping of these mice, as well as transcriptional analysis of key metabolic tissues was performed. Correlation of the expression of FHL2 and relevant genes was assessed in datasets from white adipose tissue of individuals with and without obesity.

RESULTS

FHL2 Deficiency protects mice from high-fat diet-induced weight gain, whereas glucose handling is normal. We observed enhanced energy expenditure, which may be explained by a combination of changes in multiple tissues; mild activation of brown adipose tissue with increased fatty acid uptake, increased cardiac glucose uptake and browning of white adipose tissue. Corroborating our findings in mice, expression of FHL2 in human white adipose tissue positively correlates with obesity and negatively with expression of browning-associated genes.

CONCLUSION

Our results position FHL2 as a novel regulator of obesity and energy expenditure in mice and human. Given that FHL2 expression increases during aging, we now show that low FHL2 expression associates with a healthy metabolic state.

The role of metabolic reprogramming in tubular epithelial cells during the progression of acute kidney injury

Acute kidney injury (AKI) is one of the most common clinical syndromes. AKI is associated with significant morbidity and subsequent chronic kidney disease (CKD) development. Thus, it is urgent to develop a strategy to hinder AKI progression. Renal tubules are responsible for the reabsorption and secretion of various solutes and the damage to this part of the nephron is a key mediator of AKI. As we know, many common renal insults primarily target the highly metabolically active proximal tubular cells (PTCs). PTCs are the most energy-demanding cells in the kidney. The ATP that they use is mostly produced in their mitochondria by fatty acid β-oxidation (FAO). But, when PTCs face various biological stresses, FAO will shut down for a time that outlives injury. Recent studies have suggested that surviving PTCs can adapt to FAO disruption by increasing glycolysis when facing metabolic constraints, although PTCs do not perform glycolysis in a normal physiological state. Enhanced glycolysis in a short period compensates for impaired energy production and exerts partial renal-protective effects, but its long-term effect on renal function and AKI progression is not promising. Deranged FAO and enhanced glycolysis may contribute to the AKI to CKD transition through different molecular biological mechanisms. In this review, we concentrate on the recent pathological findings of AKI with regards to the metabolic reprogramming in PTCs, confirming that targeting metabolic reprogramming represents a potentially effective therapeutic strategy for the progression of AKI.

Differentiation of THP-1 monocytes to macrophages increased mitochondrial DNA copy number but did not increase expression of mitochondrial respiratory proteins or mitochondrial transcription factor A

Monocytes are differentiated into macrophages. In this study, mitochondrial DNA copy number (mtDNAcn) levels and downstream events such as the expression of respiratory chain mRNAs were investigated during the phorbol 12-myristate 13-acetate (PMA)-induced differentiation of monocytes. Although PMA treatment increased mtDNAcn, the expression levels of mRNAs encoded in mtDNA were decreased. The levels of mitochondrial transcription factor A mRNA and protein were also decreased. The levels of coenzyme Q10 remained unchanged. These results imply that, although mtDNAcn is considered as a health marker, the levels of mtDNAcn may not always be consistent with the parameters of mitochondrial functions.

Overexpression of Peroxisome Proliferator-Activated Receptor γ Coactivator 1-α Protects Cardiomyocytes from Lipopolysaccharide-Induced Mitochondrial Damage and Apoptosis

Mitochondrial damage is considered one of the main pathogenetic mechanisms in septic cardiomyopathy. Peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) is critical for maintaining energy homeostasis in different organs and in various physiological and pathological states. It is also a key regulator gene in mitochondrial metabolism. In this study, we investigated whether regulation of the PGC-1α gene had protective effects on septic cardiomyopathy. We developed a rat model of septic cardiomyopathy. H9c2 myocardiocytes were treated with lipopolysaccharide (LPS) and PGC-1α expression measured. PGC-1α-overexpressing lentivirus was used to transfect H9c2 cells. ZLN005 was used to activate PGC-1α. The effect of the inhibition of PGC-1α expression on myocardial cell injury and its underlying mechanisms were also explored. Cell viability was measured by CCK-8 assay. Mitochondrial damage was determined by measuring cellular ATP, reactive oxygen species, and the mitochondrial membrane potential. An apoptosis analysis kit was used to measure cellular apoptosis. Mitochondrial DNA was extracted and real-time PCR performed. LC3B, mitochondrial transcription factor A (TFA), P62, Bcl2, and Bax were determined by immunofluorescence. LC3B, TFA, P62, Parkin, PTEN-induced putative kinase 1, and PGC-1α proteins were determined by Western blotting. We found mitochondrial damage and apoptotic cells in the myocardial tissue of rats with septic cardiomyopathy and in LPS-treated cardiomyocytes. PGC-1α expression was decreased in the late phase of septic cardiomyopathy and in LPS-treated cardiomyocytes. PGC-1α activation by ZLN005 and PGC-1α overexpression reduced apoptosis in myocardiocytes after LPS incubation. PGC-1α gene overexpression alleviated LPS-induced cardiomyocyte mitochondrial damage by activating mitochondrial biogenesis and autophagy functions. Our study indicated that mitochondrial damage and apoptosis occurred in septic cardiomyopathy and LPS-treated cardiomyocytes. The low expression level of PGC-1α protein may have contributed to this damage. By activating the expression of PGC-1α, apoptosis was reduced in cardiomyocytes. The underlying mechanism may be that PGC-1α can activate mitochondrial biogenesis and autophagy functions, reducing mitochondrial damage and thereby reducing apoptosis.

Protective Effect of Jiang Tang Xiao Ke Granules against Skeletal Muscle IR via Activation of the AMPK/SIRT1/PGC-1α Signaling Pathway

The Jiang Tang Xiao Ke (JTXK) granule is a classic Chinese herbal formula that has been put into clinical use in the treatment of type 2 diabetes mellitus for decades. However, whether its ability to ameliorate skeletal muscle insulin resistance (IR) is through modulation of the AMPK/SIRT1/PGC-1α signaling pathway remains unknown. Therefore, we aimed to investigate the effects of JTXK granules on IR in skeletal muscle of high-fat diet-induced diabetic mice and C2C12 cells and analyze the underlying mechanisms. In the present study, we showed that JTXK granules attenuated body weight gain, reduced body fat mass, improved body lean mass, and enhanced muscle performance of diabetic mice. JTXK granules also improved glucose metabolism and skeletal muscle insulin sensitivity and partially reversed abnormal serum lipid levels, which might be related to the regulation of the AMPK/SIRT1/PGC-1α pathway, both in skeletal muscle tissue of diabetic mice and in C2C12 cells. Furthermore, drug-containing serum of JTXK granules was capable of enhancing glucose uptake and mitochondrial respiration in C2C12 cells, and AMPKα was proven to be closely involved in this process. Taken together, these results suggest that the JTXK granule ameliorates skeletal muscle IR through activation of the AMPK/SIRT1/PGC-1α signaling pathway, which offers a novel perspective of this formula to combat IR-related metabolic diseases.

Genetic and Functional Characterization of Novel Brown-Like Adipocytes Around the Lamprey Brain

During the process of vertebrate evolution, many thermogenic organs and mechanisms have appeared. Mammalian brown adipose tissue (BAT) generates heat through the uncoupling oxidative phosphorylation of mitochondria, acts as a natural defense against hypothermia and inhibits the development of obesity. Although the existence, cellular origin and molecular identity of BAT in humans have been well studied, the genetic and functional characteristics of BAT from lampreys remain unknown. Here, we identified and characterized a novel, naturally existing brown-like adipocytes at the lamprey brain periphery. Similar to human BAT, the lamprey brain periphery contains brown-like adipocytes that maintain the same morphology as human brown adipocytes, containing multilocular lipid droplets and high mitochondrion numbers. Furthermore, we found that brown-like adipocytes in the periphery of lamprey brains responded to thermogenic reagent treatment and cold exposure and that lamprey UCP2 promoted precursor adipocyte differentiation. Molecular mapping by RNA-sequencing showed that inflammation in brown-like adipocytes treated with LPS and 25HC was enhanced compared to controls. The results of this study provide new evidence for human BAT research and demonstrate the multilocular adipose cell functions of lampreys, including: (1) providing material energy and protecting structure, (2) generating additional heat and contributing to adaptation to low-temperature environments, and (3) resisting external pathogens.

Bisphenol-A inhibits mitochondrial biogenesis via impairment of GFER mediated mitochondrial protein import in the rat brain hippocampus

Mitochondrial biogenesis relies on different protein import machinery, as mitochondrial proteins are imported from the cytosol. The mitochondrial intermembrane space assembly (MIA) pathway consists of GFER/ALR and CHCHD4/Mia40, responsible for importing proteins and their oxidative folding inside the mitochondria. The MIA pathway plays an essential role in complex IV (COX IV) biogenesis via importing copper chaperone COX17, associated with the respiratory chain. BPA, an environmental toxicant, found in consumable plastics, causes neurotoxicity via impairment in mitochondrial dynamics, neurogenesis, and cognitive functions. We studied the levels of key regulatory proteins of mitochondrial import pathways and mitochondrial biogenesis after BPA exposure in the rat hippocampus. BPA caused a significant reduction in the levels of mitochondrial biogenesis proteins (PGC1α, and TFAM) and mitochondrial import protein (GFER). Immunohistochemical analysis showed reduced co-localization of NeuN with GFER, PGC-1α, and TFAM suggesting impaired mitochondrial biogenesis and protein import. BPA exposure resulted in damaged mitochondria with distorted cristae in neurons and caused a significant reduction in GFER localization inside IMS as depicted by immunogold electron microscopy. The reduced levels of GFER resulted in defective COX17 import. The translocation of cytochrome c into the cytosol and increased cleaved caspase-3 levels triggered apoptosis due to BPA toxicity. Overall, our study implicates GFER as a potential target for impaired mitochondrial protein machinery, biogenesis, and apoptosis against BPA neurotoxicity in the rat hippocampus.

Protective Effects of Huangqi Shengmai Yin on Type 1 Diabetes-Induced Cardiomyopathy by Improving Myocardial Lipid Metabolism

Diabetic cardiomyopathy (DCM) is one of the many complications of diabetes. DCM leads to cardiac insufficiency and myocardial remodeling and is the main cause of death in diabetic patients. Abnormal lipid metabolism plays an important role in the occurrence and development of DCM. Huangqi Shengmai Yin (HSY) has previously been shown to alleviate signs of heart disease. Here, we investigated whether HSY could improve cardiomyopathy caused by type 1 diabetes mellitus (T1DM) and improve abnormal lipid metabolism in the diabetic heart. Streptozotocin (STZ) was used to establish the T1DM mouse model, and T1DM mice were subsequently treated with HSY for eight weeks. The changes in the cardiac conduction system, histopathology, blood myocardial injury indices, and lipid content and expression of proteins related to lipid metabolism were evaluated. Our results showed that HSY could improve electrocardiogram; decrease the serum levels of CK-MB, LDH, and BNP; alleviate histopathological changes in cardiac tissue; and decrease myocardial lipid content in T1DM mice. These results indicate that HSY has a protective effect against T1DM-induced myocardial injury in mice and that this effect may be related to the improvement in myocardial lipid metabolism.

Integrated signaling system under endoplasmic reticulum stress in eukaryotic microorganisms

The endoplasmic reticulum (ER) is a multifunctional organelle, which is crucial for correct folding and assembly of secretory and transmembrane proteins. Perturbations of ER function can cause ER stress. ER stress can activate the unfolded protein response (UPR) to cope with the accumulation of misfolded proteins and protein toxicity. UPR is a coordination system that regulates transcription and translation, leading to the recovery of ER homeostasis or cell death. However, cells have an integrated signaling system to cope with ER stress, which helps cells to restore and balance their ER function. The main components of this system are ER-associated degradation (ERAD), autophagy, hypoxia signaling, and mitochondrial biogenesis. If the balance cannot be restored, the imbalance will lead to cell death or apoptosis, or even to a series of diseases. In this review, a series of activities to restore the homeostasis of cells during ER stress are discussed. KEY POINTS: • Endoplasmic reticulum (ER) plays a key role in the biological process of cells. • Perturbations of ER function can cause ER stress, including the ER overload response (EOR), sterol-regulated cascade reaction, and the UPR. • Cells have an integrated signaling system (ERAD, autophagy, hypoxia signaling, and mitochondrial biogenesis) to cope with the adverse impact caused by ER stress.

Effects of omega-3 fatty acids and metformin combination on diabetic cardiomyopathy in rats through autophagic pathway

Diabetic cardiomyopathy is a primary cause of increased morbidity and mortality in diabetics. Evidence has suggested a pivotal role for interrupted mitochondrial dynamics and quality control machinery in the onset and development of diabetic cardiomyopathy. Sequestosome 1 (SQSTM1) is a major reporter of selective autophagic activity. Other than controlling the expression of genes involved in mitochondrial biogenesis, recently peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α) was reported to directly affect SQSTM1 gene expression. Calcineurin, a pivotal mediator of cardiac hypertrophy, has been also linked to enhanced expression of SQSTM1. This study aimed to test the cardioprotective effects of adding ω-3 polyunsaturated fatty acids (PUFAs) to metformin in a rat model of type 2 diabetes mellitus and to evaluate the molecular mechanisms underlying their effects on mitochondrial quality. Diabetes was induced in male Sprague Dawley rats by a high-fat diet for 6 weeks, followed by a low-dose streptozotocin (35 mg/kg). Diabetic rats were either treated with metformin (150 mg/kg/d), ω-3 PUFAs (300 mg/kg/d), or their combination in the same doses for further 8 weeks. Along with metabolic and pathological derangements, we report that correlating with electron microscopic evidence of mitochondrial degeneration, gene expression of the autophagic indicators SQSTM1, PGC-1α, and calcineurin were decreased in the hearts of diabetic rats. Independent of its anti-hyperglycemic effects, metformin successfully preserved mitochondrial integrity and upregulated myocardial PGC-1α, calcineurin, and SQSTM1 gene expression. ω-3 PUFAs possess synergistic cardioprotection when added to metformin, suggested by improvements in myocardial ultrastructure, autophagic activity, and SQSTM1 gene expression.

Sestrin regulates acute chill coma recovery in Drosophila melanogaster

When chill-susceptible insects are exposed to low temperatures they enter a temporary state of paralysis referred to as a chill coma. The most well-studied physiological mechanism of chill coma onset and recovery involves regulation of ion homeostasis. Previous studies show that changes in metabolism may also underlie the ability to recovery quickly, but the roles of genes that regulate metabolic homeostasis in chill coma recovery time (CCRT) are not well understood. Here, we investigate the roles of Sestrin and Spargel (Drosophila homolog of PGC-1α), which are involved in metabolic homeostasis and substrate oxidation, on CCRT in Drosophila melanogaster. We find that sestrin and spargel mutants have impaired CCRT. sestrin is required in the muscle and nervous system tissue for normal CCRT and spargel is required in muscle and adipose. On the basis that exercise induces sestrin and spargel, we also test the interaction of cold and exercise. We find that pre-treatment with one of these stressors does not consistently confer acute protection against the other. We conclude that Sestrin and Spargel are important in the chill coma response, independent of their role in exercise.

Berteroin ameliorates lipid accumulation through AMPK-mediated regulation of hepatic lipid metabolism and inhibition of adipocyte differentiation

AIMS

Berteroin (5-methylthiopentyl isothiocyanate) is a naturally occurring sulforaphane analog containing a non-oxidized sulfur atom in cruciferous vegetables. The objectives of the present study were to determine the effects of berteroin on lipid metabolism in hepatocytes and adipocytes and to elucidate the mechanisms involved.

MAIN METHODS

The effect of berteroin on lipid metabolism were evaluated in liver X receptor α agonist-stimulated HepG2 cells and adipocyte differentiation-induced 3T3-L1 cells using MTT assay, western blot, real time polymerase chain reaction, oil red O staining, and triglyceride assay.

KEY FINDINGS

T0901317 treatment increased the expression of sterol regulatory element binding protein (SREBP)-1c, a major transcription factor that mediates lipogenesis, and berteroin pretreatment significantly inhibited the expressions of T0901317-induced SREBP-1c and lipogenic genes. Especially, berteroin had a greater inhibitory effect on T0901317-induced SREBP-1c activation than sulforaphane, AICAR, or metformin. Berteroin also markedly suppressed lipid droplet formations and triglyceride accumulations caused by both T0901317 stimulation in HepG2 hepatocytes and differentiation induction in 3T3-L1 preadipocytes. However, berteroin significantly increased the expression of mitochondrial fatty acid oxidation-related genes (carnitine palmitoyltransferase 1 (CPT-1) and peroxisome proliferator-activated receptor gamma coactivator-1α) and the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) in HepG2 cells. Interestingly, effects of berteroin on the expressions of SREBP-1c protein and CPT-1 mRNA were remarkably prevented by compound C (an AMPK inhibitor).

SIGNIFICANCE

Our results suggest berteroin-inhibited hepatic lipid accumulation and adipocyte differentiation might be mediated by AMPK activation and that berteroin might be useful for the prevention, amelioration, and treatment of metabolic diseases, including hepatic steatosis.

Novel regulation of renal gluconeogenesis by Atp6ap2 in response to high fat diet via PGC1-α/AKT-1 pathway

Recent studies suggested that renal gluconeogenesis is substantially stimulated in the kidney in presence of obesity. However, the mechanisms responsible for such stimulation are not well understood. Recently, our laboratory demonstrated that mice fed high fat diet (HFD) exhibited increase in renal Atp6ap2 [also known as (Pro)renin receptor] expression. We hypothesized that HFD upregulates renal gluconeogenesis via Atp6ap2-PGC-1α and AKT pathway. Using real-time polymerase chain reaction, western blot analysis and immunostaining, we evaluated renal expression of the Atp6ap2 and renal gluconeogenic enzymes, PEPCK and G6Pase, in wild type and inducible nephron specific Atp6ap2 knockout mice fed normal diet (ND, 12 kcal% fat) or a high-fat diet (HFD, 45 kcal% fat) for 8 weeks. Compared with ND, HFD mice had significantly higher body weight (23%) (P < 0.05), renal mRNA and protein expression of Atp6ap2 (39 and 35%), PEPCK (44 and 125%) and G6Pase (39 and 44%) respectively. In addition, compared to ND, HFD mice had increased renal protein expression of PGC-1α by 32% (P < 0.05) and downregulated AKT by 33% (P < 0.05) respectively in renal cortex. Atp6ap2-KO abrogated these changes in the mice fed HFD. In conclusion, we identified novel regulation of renal gluconeogenesis by Atp6ap2 in response to high fat diet via PGC1-α/AKT-1 pathway.

The intestinal microbiota contributes to the growth and physiological state of muscle tissue in piglets

Although the importance of the intestinal microbiota in host growth and health is well known, the relationship between microbiota colonization and muscle development is unclear. In this study, the direct causal effects of the colonization of gut microorganisms on the muscle tissue of piglets were investigated. The body weight and lean mass of germ-free (GF) piglets were approximately 40% lower than those of normal piglets. The deletion of the intestinal microbiota led to weakened muscle function and a reduction in myogenic regulatory proteins, such as MyoG and MyoD, in GF piglets. In addition, the blinded IGF1/AKT/mTOR pathway in GF piglets caused muscle atrophy and autophagy, which were characterized by the high expression of Murf-1 and KLF15. Gut microbiota introduced to GF piglets via fecal microbiota transplantation not only colonized the gut but also partially restored muscle growth and development. Furthermore, the proportion of slow-twitch muscle fibers was lower in the muscle of GF piglets, which was caused by the reduced short-chain fatty acid content in the circulation and impaired mitochondrial function in muscle. Collectively, these findings suggest that the growth, development and function of skeletal muscle in animals are mediated by the intestinal microbiota.

AdipoRon and Other Adiponectin Receptor Agonists as Potential Candidates in Cancer Treatments

The high mortality rate together with an ever-growing number of annual cases have defined neoplastic disorders as “the real 21st-century disease”. Its dubious distinction also results from conventional therapy failure, which has made cancer an orphan disease. Therefore, innovative and alternative therapeutic strategies are mandatory. The ability to leverage human naturally occurring anti-tumor defenses has always represented a fascinating perspective, and the immuno blockage approval in cancer treatment represents in timeline the latest success. As a multifunctional organ, adipose tissue releases a large amount of adipokines having both carcinogenic and antitumor properties. The negative correlation between serum levels and risk for developing malignancies, as well as the huge number of existing preclinical studies, have identified adiponectin as a potential anticancer adipokine. Nevertheless, its usage in clinical has constantly clashed with the inability to reproduce a mimic synthetic compound. Between 2011 and 2013, two distinct adiponectin receptor agonists were recognized, opening new scenarios even in cancer. Here, we review the first orally active adiponectin receptor agonists AdipoRon, from the discovery to the anticancer evidence. Including our latest findings in osteosarcoma models, we summarize AdipoRon and other existing agonists state-of-art, questioning about the feasibility assessment of this strategy in cancer treatment.

P2Y2R Deficiency Ameliorates Hepatic Steatosis by Reducing Lipogenesis and Enhancing Fatty Acid β-Oxidation through AMPK and PGC-1α Induction in High-Fat Diet-Fed Mice

Non-alcoholic fatty liver disease (NAFLD) is a chronic metabolic liver disease associated with obesity and insulin resistance. Activation of the purinergic receptor P2Y2R has been reported to promote adipogenesis, inflammation and dyslipidemia in adipose tissues in obese mice. However, the role of P2Y2R and its mechanisms in NAFLD remain unknown. We hypothesized that P2Y2R deficiency may play a protective role in NAFLD by modulating lipid metabolism in the liver. In this study, we fed wild type and P2Y2R knockout mice with a high-fat diet (HFD) for 12 weeks and analyzed metabolic phenotypes. First, P2Y2R deficiency effectively improved insulin resistance with a reduction in body weight and plasma insulin. Second, P2Y2R deficiency attenuated hepatic lipid accumulation and injury with reduced alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels. Third, P2Y2R deficiency decreased the expression of fatty acid synthesis mediators (cluster of differentiation (CD36), fatty acid synthase (FAS), and stearoyl-CoA desaturase 1 (SCD1)); and increased the expression of adipose triglyceride lipase (ATGL), a lipolytic enzyme. Mechanistically, P2Y2R deficiency increased the AMP-activated protein kinase (AMPK) activity to improve mitochondrial fatty acid β-oxidation (FAO) by regulating acetyl-CoA carboxylase (ACC) and carnitine palmitoyltransferase 1A (CPT1A)-mediated FAO pathway. In addition, P2Y2R deficiency increased peroxisome proliferator-activated gamma co-activator-1α (PGC-1α)-mediated mitochondrial biogenesis. Conclusively, P2Y2R deficiency ameliorated HFD-induced hepatic steatosis by enhancing FAO through AMPK signaling and PGC-1α pathway, suggesting P2Y2R as a promising therapeutic target for NAFLD.

Effects of exercise on cellular and tissue aging

The natural aging process is carried out by a progressive loss of homeostasis leading to a functional decline in cells and tissues. The accumulation of these changes stem from a multifactorial process on which both external (environmental and social) and internal (genetic and biological) risk factors contribute to the development of adult chronic diseases, including type 2 diabetes mellitus (T2D). Strategies that can slow cellular aging include changes in diet, lifestyle and drugs that modulate intracellular signaling. Exercise is a promising lifestyle intervention that has shown antiaging effects by extending lifespan and healthspan through decreasing the nine hallmarks of aging and age-associated inflammation. Herein, we review the effects of exercise to attenuate aging from a clinical to a cellular level, listing its effects upon various tissues and systems as well as its capacity to reverse many of the hallmarks of aging. Additionally, we suggest AMPK as a central regulator of the cellular effects of exercise due to its integrative effects in different tissues. These concepts are especially relevant in the setting of T2D, where cellular aging is accelerated and exercise can counteract these effects through the reviewed antiaging mechanisms.

High Dietary Fat Consumption Impairs Axonal Mitochondrial Function In Vivo

Peripheral neuropathy (PN) is the most common complication of prediabetes and diabetes. PN causes severe morbidity for Type 2 diabetes (T2D) and prediabetes patients, including limb pain followed by numbness resulting from peripheral nerve damage. PN in T2D and prediabetes is associated with dyslipidemia and elevated circulating lipids; however, the molecular mechanisms underlying PN development in prediabetes and T2D are unknown. Peripheral nerve sensory neurons rely on axonal mitochondria to provide energy for nerve impulse conduction under homeostatic conditions. Models of dyslipidemia in vitro demonstrate mitochondrial dysfunction in sensory neurons exposed to elevated levels of exogenous fatty acids. Herein, we evaluated the effect of dyslipidemia on mitochondrial function and dynamics in sensory axons of the saphenous nerve of a male high-fat diet (HFD)-fed murine model of prediabetes to identify mitochondrial alterations that correlate with PN pathogenesis in vivo We found that the HFD decreased mitochondrial membrane potential (MMP) in axonal mitochondria and reduced the ability of sensory neurons to conduct at physiological frequencies. Unlike mitochondria in control axons, which dissipated their MMP in response to increased impulse frequency (from 1 to 50 Hz), HFD mitochondria dissipated less MMP in response to axonal energy demand, suggesting a lack of reserve capacity. The HFD also decreased sensory axonal Ca2+ levels and increased mitochondrial lengthening and expression of PGC1α, a master regulator of mitochondrial biogenesis. Together, these results suggest that mitochondrial dysfunction underlies an imbalance of axonal energy and Ca2+ levels and impairs impulse conduction within the saphenous nerve in prediabetic PN.SIGNIFICANCE STATEMENT Diabetes and prediabetes are leading causes of peripheral neuropathy (PN) worldwide. PN has no cure, but development in diabetes and prediabetes is associated with dyslipidemia, including elevated levels of saturated fatty acids. Saturated fatty acids impair mitochondrial dynamics and function in cultured neurons, indicating a role for mitochondrial dysfunction in PN progression; however, the effect of elevated circulating fatty acids on the peripheral nervous system in vivo is unknown. In this study, we identify early pathogenic events in sensory nerve axons of mice with high-fat diet-induced PN, including alterations in mitochondrial function, axonal conduction, and intra-axonal calcium, that provide important insight into potential PN mechanisms associated with prediabetes and dyslipidemia in vivo.

Anti-obesity properties and mechanism of action of flavonoids: A review

Obesity is a major public health problem, and there is increasing scientific interest in its mechanisms, as well as a search for new compounds with antioxidant and anti-inflammatory properties that can minimize the metabolic complications associated with its pathology. One potential source of these compounds is natural products; Among these, flavonoids are a promising group of natural substances. Flavonoids are active constituents with diverse biological activities and are widely found in plants kingdom. Numerous studies have shown that flavonoids can effectively inhibit obesity and related metabolic disorders. The review synthesizes recent evidence in respect of progress in the understanding of the anti-obesity effects of flavonoids. Such effects which occurs through the modulation of proteins, genes and transcriptional factors involved in decreasing lipogenesis, increasing lipolysis, expenditure energy, stimulating fatty acids B-oxidation, digestion and metabolism of carbohydrates. In addition to mitigating inflammatory responses and suppress oxidative stress. A better understanding of the modulating effects and mechanisms of flavonoids in relation to obesity will allow us to better use these compounds to treat or even prevent obesity and its associated comorbidities.

Is the Mitochondrial Function of Keloid Fibroblasts Affected by Cytoglobin?

Background

A keloid is a benign skin tumour characterised by excessive proliferation of fibroblasts, a process that requires a sufficient amount of energy. The energy needs are associated with adequate oxygen (O₂) flow and well-functioning mitochondria. It is known that cytoglobin (CYGB) has a function in O₂ distribution. The aim of the present study was to explore whether the inhibition of CYGB expression caused impaired mitochondrial function of keloid fibroblasts.

Methods

An in vitro study was conducted on a keloid fibroblast derived from our previous study. The study was carried out in the laboratory of the Biochemistry & Molecular Biology Department, Faculty of Medicine, Universitas Indonesia (FMUI), from July to December 2018. CYGB expression was inhibited by small interfering ribonucleic acid (siRNA) and CYGB. Analysis of mitochondrial function was observed through peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), a mitochondrial biogenesis marker and the activity of the succinate dehydrogenase (SDH) enzyme in mitochondria.

Results

The CYGB gene and protein were downregulated after treatment with CYGB siRNA. Inhibition of CYGB expression with siRNA also tended to decrease the levels of PGC-1α messenger ribonucleic acid (mRNA) and protein, as well as SDH enzyme activity.

Conclusion

Inhibition of CYGB expression with siRNA tended to decrease mitochondrial biogenesis and function. This may be useful for understanding the excessive proliferation of fibroblasts in keloids and for development of treatment for keloids.

Effects of Simvastatin on Lipid Metabolism in Wild-Type Mice and Mice with Muscle PGC-1α Overexpression

Previous studies suggest that statins may disturb skeletal muscle lipid metabolism potentially causing lipotoxicity with insulin resistance. We investigated this possibility in wild-type mice (WT) and mice with skeletal muscle PGC-1α overexpression (PGC-1α OE mice). In WT mice, simvastatin had only minor effects on skeletal muscle lipid metabolism but reduced glucose uptake, indicating impaired insulin sensitivity. Muscle PGC-1α overexpression caused lipid droplet accumulation in skeletal muscle with increased expression of the fatty acid transporter CD36, fatty acid binding protein 4, perilipin 5 and CPT1b but without significant impairment of muscle glucose uptake. Simvastatin further increased the lipid droplet accumulation in PGC-1α OE mice and stimulated muscle glucose uptake. In conclusion, the impaired muscle glucose uptake in WT mice treated with simvastatin cannot be explained by lipotoxicity. PGC-1α OE mice are protected from lipotoxicity of fatty acids and triglycerides by increased the expression of FABP4, formation of lipid droplets and increased expression of CPT1b.

Energy metabolism disorders and potential therapeutic drugs in heart failure

Heart failure (HF) is a global public health problem with high morbidity and mortality. A large number of studies have shown that HF is caused by severe energy metabolism disorders, which result in an insufficient heart energy supply. This deficiency causes cardiac pump dysfunction and systemic energy metabolism failure, which determine the development of HF and recovery of heart. Current HF therapy acts by reducing heart rate and cardiac preload and afterload, treating the HF symptomatically or delaying development of the disease. Drugs aimed at cardiac energy metabolism have not yet been developed. In this review, we outline the main characteristics of cardiac energy metabolism in healthy hearts, changes in metabolism during HF, and related pathways and targets of energy metabolism. Finally, we discuss drugs that improve cardiac function via energy metabolism to provide new research ideas for the development and application of drugs for treating HF.

The role of ceramide accumulation in human induced pluripotent stem cell-derived cardiomyocytes on mitochondrial oxidative stress and mitophagy

Oversupply of fatty acids (FAs) to cardiomyocytes (CMs) is associated with increased ceramide content and elevated the risk of lipotoxic cardiomyopathy. Here we investigate the role of ceramide accumulation on mitochondrial function and mitophagy in cardiac lipotoxicity using CMs derived from human induced pluripotent stem cell (hiPSC). Mature CMs derived from hiPSC exposed to the diabetic-like environment or transfected with plasmids overexpressing serine-palmitoyltransferase long chain base subunit 1 (SPTLC1), a subunit of the serine-palmitoyltransferase (SPT) complex, resulted in increased intracellular ceramide levels. Accumulation of ceramides impaired insulin-dependent phosphorylation of Akt through activating protein phosphatase 2A (PP2A) and disturbed gene and protein levels of key metabolic enzymes including GLUT4, AMPK, PGC-1α, PPARα, CD36, PDK4, and PPARγ compared to controls. Analysis of CMs oxidative metabolism using a Seahorse analyzer showed a significant reduction in ATP synthesis-related O₂ consumption, mitochondrial β-oxidation and respiratory capacity, indicating an impaired mitochondrial function under diabetic-like conditions or SPTLC1-overexpression. Further, ceramide accumulation increased mitochondrial fission regulators such as dynamin-related protein 1 (DRP1) and mitochondrial fission factor (MFF) as well as auto/mitophagic proteins LC3B and PINK-1 compared to control. Incubation of CMs with the specific SPT inhibitor (myriocin) showed a significant increase in mitochondrial fusion regulators the mitofusin 2 (MFN2) and optic atrophy 1 (OPA1) as well as p-Akt, PGC-1 α, GLUT-4, and ATP production. In addition, a significant decrease in auto/mitophagy and apoptosis was found in CMs treated with myriocin. Our results suggest that ceramide accumulation has important implications in driving insulin resistance, oxidative stress, increased auto/mitophagy, and mitochondrial dysfunction in the setting of lipotoxic cardiomyopathy. Therefore, modulation of the de novo ceramide synthesis pathway may serve as a novel therapeutic target to treat metabolic cardiomyopathy.