Network pharmacology and molecular docking combined with widely targeted metabolomics to elucidate the potential compounds and targets of Euphorbia helioscopia seeds for the treatment of pulmonary fibrosis.

BACKGROUND: The whole herb of Euphorbia helioscopia has been traditionally used for treating pulmonary tuberculosis, malaria, warts, lung cancer and bacillary dysentery for a long time in China. However, E. helioscopia seeds are often discarded and its medicinal value is often ignored, resulting in a waste of resources. METHOD: In this work, widely targeted metabolomics based on UPLC-ESI-QTRAP-MS/MS methods and metware database (MWDB) were firstly used to identify the chemical compositions of EHS. Besides, network pharmacology, molecular docking and molecular dynamics simulation were performed for elucidating the potential compounds and targets of E. helioscopia seeds for the treatment of pulmonary fibrosis via common database (like TCMSP, Genecards, DAVID, STRING) and common software (like Sybyl, Cytoscape, Pymol and Schrödinger). RESULT: The results of widely targeted metabolomics showed 231 compounds including 12 categories were identified. The highest content compositions are lipids (33.89%) followed by amino acids and derivatives (21.78%), nucleotides and derivatives (15.73%), as well as the content of functional ingredients like phenolic acids (7.33%), alkaloids (7.03%) and flavonoids (4.51%) are relatively high. Besides, the results of network pharmacology and molecular docking showed that EHS presented anti-pulmonary fibrosis medicinal value through multi-ingredients, multi-targets and multi-pathways approach. Key ingredients including 9-Hydroxy-12-oxo-15(Z)-octadecenoic acid, Nordihydrocapsiate, 1-O-Salicyl-d-glucose, 9-(Arabinosyl)hypoxanthine, Xanthosine and Galangin-7-O-glucoside. Key targets including SRC, HSP90AA1, AKT1, EGFR, JUN, EP300 and VEGFA, and key signaling pathways mainly related to AGE-RAGE, EGFR tyrosine kinase inhibitor resistance, VEGF and HIF-1 signaling pathway. Molecular dynamics simulation showed that HSP90AA1 and 9-Hydroxy-12-oxo-15(Z)-octadecenoic complex (with the highest docking score) have a stable combination effect. CONCLUSION: In conclusion, this study revealed the chemical compositions of EHS and its anti-pulmonary fibrosis medicinal effect for the first time, it will provide scientific insight for the development of EHS as medicinal resource.

VdGAL4 Modulates Microsclerotium Formation, Conidial Morphology, and Germination To Promote Virulence in Verticillium dahliae.

Verticillium dahliae Kleb is a typical soilborne pathogen that can cause vascular wilt disease on more than 400 plants. Functional analysis of genes related to the growth and virulence is crucial to revealing the molecular mechanism of the pathogenicity of V. dahliae. Glycosidase hydrolases can hydrolyze the glycosidic bond, and some can cause host plant immune response to V. dahliae. Here, we reported a functional validation of VdGAL4 as an α-galactosidase that belongs to glycoside hydrolase family 27. VdGAL4 could cause plant cell death, and its signal peptide plays an important role in cellular immune response. VdGAL4-triggered cell death depends on BAK1 and SOBIR1 in Nicotiana benthamiana. In V. dahliae, the function of VdGAL4 in mycelial growth, conidia, microsclerotium, and pathogenicity was studied by constructing VdGAL4 deletion and complementation mutants. Results showed that the deletion of VdGAL4 reduced the conidial yield and conidial germination rate of V. dahliae and changed the microscopic morphology of conidia; the mycelia were arranged more disorderly and were unable to produce microsclerotium. The VdGAL4 deletion mutants exhibited reduced utilization of different carbon sources, such as raffinose and sucrose. The VdGAL4 deletion mutants were also more sensitive to abiotic stress agents of SDS, sorbitol, low-temperature stress of 16°C, and high-temperature stress of 45°C. In addition, the VdGAL4 deletion mutants lost the ability to penetrate cellophane and its mycelium were disorderly arranged. Remarkably, VdGAL4 deletion mutants exhibited reduced pathogenicity of V. dahliae. These results showed that VdGAL4 played a critical role in the pathogenicity of V. dahliae by regulating mycelial growth, conidial morphology, and the formation of microsclerotium. IMPORTANCE This study showed that α-galactosidase VdGAL4 of V. dahliae could activate plant immune response and plays an important role in conidial morphology and yield, formation of microsclerotia, and mycelial penetration. VdGAL4 deletion mutants significantly reduced the pathogenicity of V. dahliae. These findings deepened the understanding of pathogenic virulence factors and how the mechanism of pathogenic fungi infected the host, which may help to seek new strategies for effective control of plant diseases caused by pathogenic fungi.

Natural edible pigments: A comprehensive review of resource, chemical classification, biosynthesis pathway, separated methods and application.

Natural edible pigments, high safety and low toxicity, usually possess various nutritional and pharmacological effects, and they have huge practical application value in the market. However, until now, there is no systematic review about the resources, chemical classifications and application about them. Moreover, the extracted methods and biosynthesis pathways which are very important informations for obtaining high-yield and high-purity natural edible pigments from natural resources are still lacking. Therefore, It is necessary to make a comprehensive review of natural edible pigments. In this work, we systematically summarize the resources, chemical classifications, biosynthesis pathways, extraction and separation methods, as well as application of natural edible pigments for the first time. Our work will provide reference data and give the inspiration for further industrial application of natural edible pigments.

Systematic Elaboration of the Pharmacological Targets and Potential Mechanisms of ZhiKe GanCao Decoction for Preventing and Delaying Intervertebral Disc Degeneration.

Background: ZhiKe GanCao Decoction (ZKGCD) is a commonly used traditional Chinese medicine in the clinical treatment of intervertebral disc degeneration (IDD). However, its active ingredients and mechanism of action remain unclear. This study aims to propose the systematic mechanism of ZKGCD action on IDD based on network pharmacology, molecular docking, and enrichment analysis. Methods: Firstly, the common target genes between ZKGCD and IDD were identified through relevant databases. Secondly, the protein-protein interaction (PPI) network of common genes was constructed and further analyzed to determine the core active ingredients and key genes. Thirdly, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of common genes were performed. Finally, the stability of the binding between core active ingredients and key genes was verified by molecular docking analysis. Results: "Intersecting genes-active components" network consists of 154 active ingredients and 133 common genes. The ten key genes are AKT1, TNF, IL6, TP53, IL1B, JUN, CASP3, STAT3, MMP9, and MAPK3. Meanwhile, quercetin (Mol000098), luteolin (Mol000006), and kaempferol (Mol000422) are the most important core active ingredients. The main signal pathways selected by KEGG enrichment analysis includes AGE-RAGE signaling pathway in diabetic complications (hsa04933), TNF signaling pathway (hsa04668), IL-17 signaling pathway (hsa04657), cellular senescence (hsa04218), apoptosis (hsa04210), and PI3K-Akt signaling pathway (hsa04151), which are mainly involved in inflammation, apoptosis, senescence, and autophagy. Conclusion: This study provides a basis for further elucidating the mechanism of action of ZKGCD in the treatment of IDD and offers a new perspective on the conversion of the active ingredient in ZKGCD into new drugs for treating IDD.

Disrupted coupling between salience network segregation and glucose metabolism is associated with cognitive decline in Alzheimer's disease - A simultaneous resting-state FDG-PET/fMRI study.

The aberrant organization and functioning of three core neurocognitive networks (NCNs), i.e., default-mode network (DMN), central executive network (CEN), and salience network (SN), are among the prominent features in Alzheimer's disease (AD). The dysregulation of both intra- and inter-network functional connectivities (FCs) of the three NCNs contributed to AD-related cognitive and behavioral abnormalities. Brain functional network segregation, integrating intra- and inter-network FCs, is essential for maintaining the energetic efficiency of brain metabolism. The association of brain functional network segregation, together with glucose metabolism, with age-related cognitive decline was recently shown. Yet how these joint functional-metabolic biomarkers relate to cognitive decline along with mild cognitive impairment (MCI) and AD remains to be elucidated. In this study, under the framework of the triple-network model, we performed a hybrid FDG-PET/fMRI study to evaluate the concurrent changes of resting-state brain intrinsic FCs and glucose metabolism of the three NCNs across cognitively normal (CN) (N = 24), MCI (N = 21), and AD (N = 21) groups. Lower network segregation and glucose metabolism were observed in all three NCNs in patients with AD. More interestingly, in the SN, the coupled relationship between network segregation and glucose metabolism existed in the CN group (r = 0.523, p = 0.013) and diminished in patients with MCI (r = 0.431, p = 0.065) and AD (r = 0.079, p = 0.748). Finally, the glucose metabolism of the DMN (r = 0.380, p = 0.017) and the network segregation of the SN (r = 0.363, p = 0.023) were significantly correlated with the general cognitive status of the patients. Our findings suggest that the impaired SN segregation and its uncoupled relationship with glucose metabolism contribute to the cognitive decline in AD.

Circulating humanin is lower in coronary artery disease and is a prognostic biomarker for major cardiac events in humans.

BACKGROUND: Humanin is an endogenous mitochondria-derived peptide that plays critical roles in oxidative stress, inflammation and CAD. In this study, we measured the levels of circulating humanin, markers of oxidative stress and inflammation in patients with unstable angina and MI and studied the relationship between these parameters and major adverse cardiac events (MACE). METHODS: A total of 327 subjects were recruited from the inpatient department at First Hospital of Jilin University and divided into 3 groups [control, angina and myocardial infarction (MI)] based on the clinical data and the results of the angiography. Serum humanin and thiobarbituric acid reactive substances (TBARS) were measured at the time of initial admission. The hospitalization data and MACE of all patients were collected. RESULTS: Circulating humanin levels were lower in the angina group compared to controls [124.22 ±â€¯63.02 vs. 157.77 ±â€¯99.93 pg/ml, p < 0.05] and even lower in MI patients [67.17 ±â€¯24.35 pg/ml, p < 0.05 vs controls] and oxidative stress marker were higher in MI patients compared to the control and angina groups [12.94 ±â€¯4.55 vs. 8.26 ±â€¯1.66 vs. 9.06 ±â€¯2.47 umol/ml, p < 0.05]. Lower circulating humanin levels was an independent risk factor of MI patients. Circulating humanin levels could be used to predict MACE in angina group. CONCLUSIONS: Lower circulating humanin levels was an independent risk factor for CAD, and a potential prognostic marker for mild CAD. GENERAL SIGNIFICANCE: Humanin may become a new index for the diagnosis and treatment of CAD.

Brain Intrinsic Functional Activity in Relation to Metabolic Changes in Alzheimer's Disease: A Simultaneous PET/fMRI study.

Previous studies have shown that the intrinsic brain functional activity significantly reduced in a variety of regions of Alzheimer's disease (AD) patients. However, the associated underlying metabolic mechanism remains not clear. Brain activity is primarily driven by the dynamic activity of neurons and their interconnections, which are regulated by synapses and are closely related to glucose uptakes. Simultaneous FDG-PET/fMRI imaging provides a unique opportunity to measure the concurrent brain functional activity and cerebral glucose metabolism information. In this study, using simultaneous resting-state PET/fMRI imaging, we investigated the concurrent global intrinsic activity and metabolic signal changes in AD patients. Twenty-two controls and nineteen AD patients were included. We compared the whole-brain amplitude of low frequency fluctuations (ALFF) measured using fMRI imaging and glucose uptake maps acquired from PET imaging between the two groups. Both maps showed significant reductions in the precuneus and left inferior parietal lobule (IPL) in AD compared to the control groups. Moreover, the ALFF within the precuneus and left IPL were significantly correlated with the colocalized glucose metabolism. The ALFF in the left IPL was significantly correlated with patient cognitive performance evaluated using MMSE or MoCA. Our findings provide useful insights into the understanding of brain intrinsic functional-metabolic activity and its role in AD pathology.

Simultaneous PET/fMRI Detects Distinctive Alterations in Functional Connectivity and Glucose Metabolism of Precuneus Subregions in Alzheimer's Disease.

As a central hub in the interconnected brain network, the precuneus has been reported showing disrupted functional connectivity and hypometabolism in Alzheimer's disease (AD). However, as a highly heterogeneous cortical structure, little is known whether individual subregion of the precuneus is uniformly or differentially involved in the progression of AD. To this end, using a hybrid PET/fMRI technique, we compared resting-state functional connectivity strength (FCS) and glucose metabolism in dorsal anterior (DA_pcu), dorsal posterior (DP_pcu) and ventral (V_pcu) subregions of the precuneus among 20 AD patients, 23 mild cognitive impairment (MCI) patients, and 27 matched cognitively normal (CN) subjects. The sub-parcellation of precuneus was performed using a K-means clustering algorithm based on its intra-regional functional connectivity. For the whole precuneus, decreased FCS (p = 0.047) and glucose hypometabolism (p = 0.006) were observed in AD patients compared to CN subjects. For the subregions of the precuneus, decreased FCS was found in DP_pcu of AD patients compared to MCI patients (p = 0.011) and in V_pcu for both MCI (p = 0.006) and AD (p = 0.008) patients compared to CN subjects. Reduced glucose metabolism was found in DP_pcu of AD patients compared to CN subjects (p = 0.038) and in V_pcu of AD patients compared to both MCI patients (p = 0.045) and CN subjects (p < 0.001). For both FCS and glucose metabolism, DA_pcu remained relatively unaffected by AD. Moreover, only in V_pcu, disruptions in FCS (r = 0.498, p = 0.042) and hypometabolism (r = 0.566, p = 0.018) were significantly correlated with the cognitive decline of AD patients. Our results demonstrated a distinctively disrupted functional and metabolic pattern from ventral to dorsal precuneus affected by AD, with V_pcu and DA_pcu being the most vulnerable and conservative subregion, respectively. Findings of this study extend our knowledge on the differential roles of precuneus subregions in AD.

Effect of early cardiac rehabilitation on prognosis in patients with heart failure following acute myocardial infarction.

OBJECTIVE: The purpose of this retrospective study is to evaluate the effectiveness of early cardiac rehabilitation on patients with heart failure following acute myocardial infarction. METHODS: Two hundred and thirty-two patients who developed heart failure following acute myocardial infarction were enrolled in this study. Patients were divided into heart failure with reduced ejection fraction group (n = 54) and heart failure with mid-range ejection fraction group (n = 178). Seventy-eight patients who accepted a two-week cardiac rehabilitation were further divided into two subgroups based on major adverse cardiovascular events. Key cardio-pulmonary exercise testing indicators that may affect the prognosis were identified among the cardiac rehabilitation patients. RESULTS: Early cardiac rehabilitation significantly reduced cardiac death and re-hospitalization in patients. There was more incidence of diabetes, hyperkalemia and low PETCO2 in the cardiac rehabilitation group who developed re-hospitalization. Low PETCO2 at anaerobic threshold (≤ 33.5 mmHg) was an independent risk factor for re-hospitalization. CONCLUSIONS: Early cardiac rehabilitation reduced major cardiac events in patients with heart failure following acute myocardial infarction. The lower PETCO2 at anaerobic threshold is an independent risk factor for re-hospitalization, and could be used as a evaluating hallmark for early cardiac rehabilitation.

Disrupted functional connectivity of precuneus subregions in obsessive-compulsive disorder.

Obsessive-compulsive disorder (OCD) is a chronic and disablingpsychiatric disorder with high lifetime prevalence, yet the underlying pathogenesis remains not fully understood. Increasing neuroimaging evidence has shown that the disrupted activity of brain functional hubs might contribute to the pathophysiology of OCD. Precuneus is an important brain hub which showed structural and functional abnormalities in OCD patients. However, the functional heterogeneity of the precuneus subregion has not been considered and its relation to OCD symptomatology remains to be elucidated. In this paper, a total of 73 unmedicated OCD patients and 79 matched healthy subjects were recruited and the heterogeneous functional connectivities (FCs) of the precuneus subregions were investigated using resting-state functional magnetic resonance imaging. The FC-based subdivision of the precuneus was performed using the K-means clustering algorithm, which led to a tripartite functional parcellation of precuneus. For each subregion, the distinct connectivity pattern with the whole brain was shown, using both voxel-wise and module-wise analysis, respectively. Decreased FC between dorsal posterior precuneus and vermis (corrected p<0.01) was shown in the patient group, which was negatively correlated with patient compulsions score (ρ = - 0.393, p = 0.001), indicating its contribution to the compulsive behavior inhibition of OCD. Our work might provide new insights into the understanding of precuneus subregion function and the importance of dorsal precuneus-cerebellum functional connectivity in OCD pathophysiology.

Fabrication of S-scheme CdS-g-C3N4-graphene aerogel heterojunction for enhanced visible light driven photocatalysis.

Constructing S-scheme heterojunction photocatalysts reveals a greatly improved separation efficiency of photogenerated carriers and enhanced harvesting ability of solar energy in photocatalytic field. Herein, a ternary CdS-g-C3N4-GA heterojunction has been fabricated by a facile ultrasound strategy, which behaved as a S-scheme heterojunction with an intimate interface formed, and GA played as an electronic transportation platform to promote the separation of photo-induced charge carriers, which was certified through photoelectrochemical techniques. Density functional theory calculations revealed that the different component in ternary CdS-g-C3N4-GA heterojunction demonstrated an obvious difference of work function, resulting in the charge transfer from CdS to g-C3N4 through GA with S-scheme principle. In the optimized conditions, the S-scheme CdS-g-C3N4-GA heterojunction not only displayed greatly enhanced photocatalytic performances for degradation of dye and antibiotic wastewater, but also improved photocatalytic H2 production activity. In addition, the photocatalytic mechanism and driving force of charge transfer and separation in S-scheme CdS-g-C3N4-GA heterojunction were studied. This study offers a feasible strategy to construct a ternary S-scheme heterojunction for environmental and energy photocatalysis.

Sestrin2 is an endogenous antioxidant that improves contractile function in the heart during exposure to ischemia and reperfusion stress.

Sestrin2 (Sesn2) is a stress-inducible protein that plays a critical role in the response to ischemic stress. We recently recognized that Sesn2 may protect the heart against ischemic insults by reducing the generation of reactive oxygen species (ROS). After 45 min of ischemia followed by 24 h of reperfusion, myocardial infarcts were significantly larger in Sesn2 KO hearts than in wild-type hearts. Isolated cardiomyocytes from wild-type hearts treated with hypoxia and reoxygenation (H/R) stress showed significantly greater Sesn2 levels, compared with normoxic hearts (p < 0.05). Intriguingly, the administration of adeno-associated virus 9-Sesn2 into Sesn2 knockout (KO) hearts rescued Sesn2 protein levels and significantly improved the cardiac function of Sesn2 KO mice exposed to ischemia and reperfusion. The rescued levels of Sesn2 in Sesn2 KO hearts significantly ameliorated ROS generation and the activation of ROS-related stress signaling pathways during ischemia and reperfusion. Moreover, the rescued Sesn2 levels in Sesn2 KO cardiomyocytes improved the maximal velocity of cardiomyocyte shortening by H/R stress. Rescued Sesn2 levels also improved peak height, peak shortening amplitude, and maximal velocity of the re-lengthening of Sesn2 KO cardiomyocytes subjected to H/R. Finally, the rescued Sesn2 levels significantly augmented intracellular calcium levels and reduced the mean time constant of transient calcium decay in Sesn2 KO cardiomyocytes exposed to H/R. Overall, these findings indicated that Sesn2 can act as an endogenous antioxidant to maintain intracellular redox homeostasis under ischemic stress conditions.

The Emerging Role of Sestrin2 in Cell Metabolism, and Cardiovascular and Age-Related Diseases.

Sestrins (Sesns), including Sesn1, Sesn2, and Sesn3, are cysteine sulfinyl reductases that play critical roles in the regulation of peroxide signaling and oxidant defense. Sesn2 is thought to regulate cell growth, metabolism, and survival response to various stresses, and act as a positive regulator of autophagy. The anti-oxidative and anti-aging roles of Sesn2 have been the focus of many recent studies. The role of Sesn2 in cellular metabolism and cardiovascular and age-related diseases must be analyzed and discussed. In this review, we discuss the physiological and pathophysiological roles and signaling pathways of Sesn2 in different stress-related conditions, such as oxidative stress, genotoxic stress, and hypoxia. Sesn2 is also involved in aging, cancer, diabetes, and ischemic heart disease. Understanding the actions of Sesn2 in cell metabolism and age-related diseases will provide new evidence for future experimental research and aid in the development of novel therapeutic strategies for Sesn2-related diseases.

Very Late Stent Thrombosis in Drug-Eluting Stents New Observations and Clinical Implications.

Despite the reduction in stent failure with newer-generation drug-eluting stents, very late stent thrombosis (VLST) remains an unpredictable and potentially catastrophic complication of coronary revascularization procedures and is associated with high morbidity and mortality. Here, we present an updated overview of the latest advances in understanding the causes of VLST. Clinical studies that revealed potential risk factors and pathophysiologic studies on the mechanisms of VLST are discussed. Importantly, novel insights from recent advances in intravascular imaging are included. To date, there is no clinical guideline for VLST treatment. We propose an evidence-based recommendation that an intravascular-imaging-informed percutaneous coronary intervention strategy combined with optimized antiplatelet therapy is the foundation for successful VLST clinical management. Moreover, the future of VLST prevention, such as improved patient risk stratification and advances in addressing late stent failure, are also discussed.

Targeting ALDH2 for Therapeutic Interventions in Chronic Pain-Related Myocardial Ischemic Susceptibility.

Clinical observations have demonstrated a link between chronic pain and increased ischemic heart disease mortality, but the mechanisms remain elusive. Reactive aldehydes have recently been confirmed as a new player in pain pathologies, while our previous study demonstrated that reactive aldehydes (4-HNE) induced carbonyl stress contributing to myocardial ischemic intolerance. The aim of this study was to explore whether chronic pain increases susceptibility to myocardial ischemia/reperfusion (MI/R) injury and to investigate the underlying mechanisms focusing on toxic aldehyde and carbonyl stress. Methods: Chronic pain was induced by chronic compression of the dorsal root ganglion (CCD). After 2 weeks CCD, aldehyde dehydrogenase (ALDH2) KO or wild-type (WT) littermate mice were then subjected to in vivo MI/R. Results: In CCD-WT mice, heightened nociception paralleled circulating aldehyde (4-HNE) accumulation and cardiac protein carbonylation. Mechanistically, CCD-induced 4-HNE overload provoked cardiac Sirtuin 1 (SIRT1) carbonylative inactivation and inhibited Liver kinase B1 (LKB1) - AMP-activated protein kinase (LKB1-AMPK) interaction, which resulted in exacerbated MI/R injury and higher mortality compared with non-CCD WT mice. ALDH2 deficiency further aggravated CCD-induced susceptibility to MI/R injury. Exogenous 4-HNE exposure in peripheral tissue mimicked chronic pain-induced aldehyde overload, elicited sustained allodynia and increased MI/R injury. However, cardiac-specific ALDH2 upregulation by AAV9-cTNT-mediated gene delivery significantly ameliorated chronic pain-induced SIRT1 carbonylative inactivation and decreased MI/R injury (minor infarct size, less apoptosis, and improved cardiac function). Conclusion: Collectively, chronic pain-enhanced carbonyl stress promotes myocardial ischemic intolerance by SIRT1 carbonylative inactivation and impairment of LKB1-AMPK interaction. ALDH2 activation and prevention of protein carbonylation may be a potential therapeutic target for myocardial ischemic vulnerability in chronic pain patients. Our results newly provided overlapping cellular mechanisms of chronic pain and myocardial dysfunction interplay.

Cardiomyocyte-specific deletion of Sirt1 gene sensitizes myocardium to ischaemia and reperfusion injury.

Aims: A longevity gene, Sirtuin 1 (SIRT1) and energy sensor AMP-activated protein kinase (AMPK) have common activators such as caloric restriction, oxidative stress, and exercise. The objective of this study is to characterize the role of cardiomyocyte SIRT1 in age-related impaired ischemic AMPK activation and increased susceptibility to ischemic insults. Methods and results: Mice were subjected to ligation of left anterior descending coronary artery for in vivo ischemic models. The glucose and fatty acid oxidation were measured in a working heart perfusion system. The cardiac functions by echocardiography show no difference in young wild-type C57BL/6 J (WT, 4-6 months), aged WT C57BL/6 J (24-26 months), and young inducible cardiomyocyte-specific SIRT1 knockout (icSIRT1 KO) (4-6 months) mice under physiological conditions. However, after 45 mins ischaemia and 24-h reperfusion, the ejection fraction of aged WT and icSIRT1 KO mice was impaired. The aged WT and icSIRT1 KO hearts vs. young WT hearts also show an impaired post-ischemic contractile function in a Langendorff perfusion system. The infarct size of aged WT and icSIRT1 KO hearts was larger than that of young WT hearts. The immunoblotting data demonstrated that aged WT and icSIRT1 KO hearts vs. young WT hearts had impaired phosphorylation of AMPK and downstream acetyl-CoA carboxylase during ischaemia. Intriguingly, AMPK upstream LKB1 is hyper-acetylated in both aged WT and icSIRT1 KO hearts; this could blunt activation of LKB1, leading to an impaired AMPK activation. The working heart perfusion results demonstrated that SIRT1 deficiency significantly impaired substrate metabolism in the hearts; fatty acid oxidation is augmented and glucose oxidation is blunted during ischaemia and reperfusion. Adeno-associated virus (AAV9)-Sirt1 was delivered into the aged hearts via a coronary delivery approach, which significantly rescued the protein level of SIRT1 and the ischemic tolerance of aged hearts. Furthermore, AMPK agonist can rescue the tolerance of aged heart and icSIRT1 KO heart to ischemic insults. Conclusions: Cardiac SIRT1 mediates AMPK activation via LKB1 deacetylation, and AMPK modulates SIRT1 activity via regulation of NAD+ level during ischaemia. SIRT1 and AMPK agonists have therapeutic potential for treatment of aging-related ischemic heart disease.

Sestrin2 prevents age-related intolerance to ischemia and reperfusion injury by modulating substrate metabolism.

A novel stress-inducible protein, Sestrin2 (Sesn2), declines in the heart with aging. AMPK has emerged as a pertinent stress-activated kinase that has been shown to have cardioprotective capabilities against myocardial ischemic injury. We identified the interaction between Sesn2 and AMPK in the ischemic heart. To determine whether ischemic AMPK activation-modulated by the Sesn2-AMPK complex in the heart-is impaired in aging that sensitizes the heart to ischemic insults, young C57BL/6 mice (age 3-4 mo), middle-aged mice (age 10-12 mo), and aged mice (age 24-26 mo) were subjected to left anterior descending coronary artery occlusion for in vivo regional ischemia. The ex vivo working heart system was used for measuring substrate metabolism. The protein level of Sesn2 in hearts was gradually decreased with aging. Of interest, ischemic AMPK activation was blunted in aged hearts compared with young hearts (P < 0.05); the AMPK downstream glucose uptake and the rate of glucose oxidation were significantly impaired in aged hearts during ischemia and reperfusion (P < 0.05 vs. young hearts). Myocardial infarction size was larger in aged hearts (P < 0.05 vs. young hearts). Immunoprecipitation with Sesn2 Ab revealed that cardiac Sesn2 forms a complex with AMPK and upstream liver kinase B1 (LKB1) during ischemia. Of interest, the binding affinity between Sesn2 and AMPK upstream LKB1 is impaired in aged hearts during ischemia (P < 0.05 vs. young hearts). Furthermore, Sesn2-knockout hearts demonstrate a cardiac phenotype and response to ischemic stress that is similar to wild-type aged hearts (i.e., impaired ischemic AMPK activation and higher sensitivity to ischemia- and reperfusion- induced injury). Adeno-associated virus-Sesn2 was delivered to aged hearts via a coronary delivery approach and significantly rescued the protein level of Sesn2 and the ischemic tolerance of aged hearts; therefore, Sesn2 is a scaffold protein that mediates AMPK activation in the ischemic myocardium via an interaction with AMPK upstream LKB1. Decreased Sesn2 levels in aging lead to a blunted ischemic AMPK activation, alterations in substrate metabolism, and an increased sensitivity to ischemic insults-Quan, N., Sun, W., Wang, L., Chen, X., Bogan, J. S., Zhou, X., Cates, C., Liu, Q., Zheng, Y., Li J. Sestrin2 prevents age-related intolerance to ischemia and reperfusion injury by modulating substrate metabolism.

Extracts of Magnolia Species-Induced Prevention of Diabetic Complications: A Brief Review.

Diabetic complications are the major cause of mortality for the patients with diabetes. Oxidative stress and inflammation have been recognized as important contributors for the development of many diabetic complications, such as diabetic nephropathy, hepatopathy, cardiomyopathy, and other cardiovascular diseases. Several studies have established the anti-inflammatory and oxidative roles of bioactive constituents in Magnolia bark, which has been widely used in the traditional herbal medicines in Chinese society. These findings have attracted various scientists to investigate the effect of bioactive constituents in Magnolia bark on diabetic complications. The aim of this review is to present a systematic overview of bioactive constituents in Magnolia bark that induce the prevention of obesity, hyperglycemia, hyperlipidemia, and diabetic complications, including cardiovascular, liver, and kidney.

Cardioprotective actions of Notch1 against myocardial infarction via LKB1-dependent AMPK signaling pathway.

AMP-activated protein kinase (AMPK) signaling pathway plays a pivotal role in intracellular adaptation to energy stress during myocardial ischemia. Notch1 signaling in the adult myocardium is also activated in response to ischemic stress. However, the relationship between Notch1 and AMPK signaling pathways during ischemia remains unclear. We hypothesize that Notch1 as an adaptive signaling pathway protects the heart from ischemic injury via modulating the cardioprotective AMPK signaling pathway. C57BL/6J mice were subjected to an in vivo ligation of left anterior descending coronary artery and the hearts from C57BL/6J mice were subjected to an ex vivo globe ischemia and reperfusion in the Langendorff perfusion system. The Notch1 signaling was activated during myocardial ischemia. A Notch1 γ-secretase inhibitor, dibenzazepine (DBZ), was intraperitoneally injected into mice to inhibit Notch1 signaling pathway by ischemia. The inhibition of Notch1 signaling by DBZ significantly augmented cardiac dysfunctions caused by myocardial infarction. Intriguingly, DBZ treatment also significantly blunted the activation of AMPK signaling pathway. The immunoprecipitation experiments demonstrated that an interaction between Notch1 and liver kinase beta1 (LKB1) modulated AMPK activation during myocardial ischemia. Furthermore, a ligand of Notch1 Jagged1 can significantly reduce cardiac damage caused by ischemia via activation of AMPK signaling pathway and modulation of glucose oxidation and fatty acid oxidation during ischemia and reperfusion. But Jagged1 did not have any cardioprotections on AMPK kinase dead transgenic hearts. Taken together, the results indicate that the cardioprotective effect of Notch1 against ischemic damage is mediated by AMPK signaling via an interaction with upstream LKB1.