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Role of WHO.

Pretreatment with Tilianin improves mitochondrial energy metabolism and oxidative stress in rats with myocardial ischemia/reperfusion injury via AMPK/SIRT1/PGC-1 alpha signaling pathway.

Reducing oxidative stress is a crucial therapeutic strategy for ameliorating diabetic myocardial ischemia/reperfusion (MI/R) injury. Honokiol (HKL) acts as an effective cardioprotective agent for its strong antioxidative activity. However, its roles and underlying mechanisms against MI/R injury in type 1 diabetes (T1D) remain unknown. Since SIRT1 and Nrf2 are pivotal regulators in diabetes mellitus patients suffering from MI/R injury, we hypothesized that HKL ameliorates diabetic MI/R injury via the SIRT1-Nrf2 signaling pathway. Streptozotocin-induced T1D rats and high-glucose-treated H9c2 cells were exposed to HKL, with or without administration of the SIRT1 inhibitor EX527, SIRT1 siRNA, or Nrf2 siRNA, and then subjected to I/R operation. We found that HKL markedly improved the postischemic cardiac function, decreased the infarct size, reduced the myocardial apoptosis, and diminished the reactive oxygen species generation. Intriguingly, HKL remarkably activated SIRT1 signaling, enhanced Nrf2 nuclear translocation, increased antioxidative signaling, and decreased apoptotic signaling. However, these effects were largely abolished by EX527 or SIRT1 siRNA. Additionally, our cellular experiments showed that Nrf2 siRNA blunted the cytoprotective effects of HKL, without affecting SIRT1 expression and activity. Collectively, these novel findings indicate that HKL abates MI/R injury in T1D by ameliorating myocardial oxidative damage and apoptosis via the SIRT1-Nrf2 signaling pathway.

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Honokiol Ameliorates Myocardial Ischemia/Reperfusion Injury in Type 1 Diabetic Rats by Reducing Oxidative Stress and Apoptosis through Activating the SIRT1-Nrf2 Signaling Pathway.

Hydrogen sulfide (H2S) has arisen as a critical gasotransmitter signaling molecule modulating cellular biological events related to health and diseases in heart, brain, liver, vascular systems and immune response. Three enzymes mediate the endogenous production of H2S: cystathione β-synthase (CBS), cystathione γ-lyase (CSE) and 3-mercaptopyruvate sulfurtransferase (3-MST). CBS and CSE localizations are organ-specific. 3-MST is a mitochondrial and cytosolic enzyme. The generation of H2S is firmly regulated by these enzymes under normal physiological conditions. Recent studies have highlighted the role of H2S in cellular redox homeostasis, as it displays significant antioxidant properties. H2S exerts antioxidant effects through several mechanisms, such as quenching reactive oxygen species (ROS) and reactive nitrogen species (RNS), by modulating cellular levels of glutathione (GSH) and thioredoxin (Trx-1) or increasing expression of antioxidant enzymes (AOE), by activating the transcription factor nuclear factor (erythroid-derived 2)-like 2 (NRF2). H2S also influences the activity of the histone deacetylase protein family of sirtuins, which plays an important role in inhibiting oxidative stress in cardiomyocytes and during the aging process by modulating AOE gene expression. This review focuses on the role of H2S in NRF2 and sirtuin signaling pathways as they are related to cellular redox homeostasis.

https://www.mdpi.com/2076-3921/7/10/129/pdf

Role of Hydrogen Sulfide in NRF2- and Sirtuin-Dependent Maintenance of Cellular Redox Balance.

The peroxisome proliferator-activated receptor γ (PPARγ) coactivator-1s (PGC-1s) can induce the expression of several downstream genes that play pivotal roles in the regulation of mitochondrial biogenesis and metabolism in the heart. Moreover, PGC-1 signaling pathways have also been reported to play a critical role in cardioprotection. Given the significance of PGC-1 coactivators, we summarize the current literature on the molecular mechanisms and roles of PGC-1s in cardiac metabolism. Thus, in this review, we first introduce the basic knowledge regarding PGC-1 signaling pathways. We then discuss their roles in heart metabolism. Moreover, we describe several significant treatments that target the PGC-1 signaling pathway. This review presents the significant roles of PGC-1s in cardiac metabolism and may contribute to the promotion of PGC-1 signaling pathway as a novel therapeutic target.

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PGC-1: The Energetic Regulator in Cardiac Metabolism.

Diallyl trisulfide (DATS) protects against apoptosis during myocardial ischemia-reperfusion (MI/R) injury in diabetic state, although the underlying mechanisms remain poorly defined. Previously, we and others demonstrated that silent information regulator 1 (SIRT1) activation inhibited oxidative stress and endoplasmic reticulum (ER) stress during MI/R injury. We hypothesize that DATS reduces diabetic MI/R injury by activating SIRT1 signaling. Streptozotocin (STZ)-induced type 1 diabetic rats were subjected to MI/R surgery with or without perioperative administration of DATS (40 mg/kg). We found that DATS treatment markedly improved left ventricular systolic pressure and the first derivative of left ventricular pressure, reduced myocardial infarct size as well as serum creatine kinase and lactate dehydrogenase activities. Furthermore, the myocardial apoptosis was also suppressed by DATS as evidenced by reduced apoptotic index and cleaved caspase-3 expression. However, these effects were abolished by EX527 (the inhibitor of SIRT1 signaling, 5 mg/kg). We further found that DATS effectively upregulated SIRT1 expression and its nuclear distribution. Additionally, PERK/eIF2α/ATF4/CHOP-mediated ER stress-induced apoptosis was suppressed by DATS treatment. Moreover, DATS significantly activated Nrf-2/HO-1 antioxidant signaling pathway, thus reducing Nox-2/4 expressions. However, the ameliorative effects of DATS on oxidative stress and ER stress-mediated myocardial apoptosis were inhibited by EX527 administration. Taken together, these data suggest that perioperative DATS treatment effectively ameliorates MI/R injury in type 1 diabetic setting by enhancing cardiac SIRT1 signaling. SIRT1 activation not only upregulated Nrf-2/HO-1-mediated antioxidant signaling pathway but also suppressed PERK/eIF2α/ATF4/CHOP-mediated ER stress level, thus reducing myocardial apoptosis and eventually preserving cardiac function.

Diallyl trisulfide ameliorates myocardial ischemia–reperfusion injury by reducing oxidative stress and endoplasmic reticulum stress-mediated apoptosis in type 1 diabetic rats: role of SIRT1 activation

The successful treatment of military combat casualties with penetrating injuries is significantly dependent on the time needed to get the patient to an adequate treatment facility Profound hypothermia-induced suspended animation for delayed resuscitation (SADR) is a novel approach for inducing cardiac arrest and buying additional time for such injuries However, the time used to safely administer circulatory arrest (CA) is controversial The goal of this study was to evaluate the safety of hypothermia-induced SADR over 90 and 120 min time intervals Sixteen male BAMA minipigs were randomized into two groups: CA90 group (90 min, n = 8) and CA120 group (120 min, n = 8) Cannulation of the right common carotid arteries and internal jugular veins was performed to establish cardiopulmonary bypass for each animal Through the perfusion of cold organ preservation solution (OPS), cardioplegia and profound hypothermia (15 °C) were induced After CA, cardiopumonary bypass (CPB) was restarted, and the animals were gradually re-warmed and resuscitated The animals were assisted with ventilators until spontaneous breathing was achieved The index of hemodynamic perioperative serum chemistry values [alanine transaminase (ALT), aspartate aminotransferase (AST), creatinine (CR), lactic dehydrogenase (LDH) and troponin T (TnT)] and survival were observed from pre-operation to 7 days post-operation Fifteen animals were enrolled in the experiment, while 1 animal in CA120 group died from surgical error All 8 animals in CA90 group recovered, with only 1 animal displaying mild disability However, in CA120 group, only 2 animals survived with severe disability, and the other 5 animals died after 2 days post-operation In CA90 group, the perioperative serum chemistry values increased at 1 day post-operation (ALT 8443 ± 1865 U/L; AST 8899 ± 2319 U/L; Cr 8790 ± 2449 μmol/L; LDH 189413 ± 32226 U/L; TnT 0849 ± 0135 ng/ml) but decreased to normal or almost normal levels at 7 days post-operation (ALT 5248 ± 904 U/L; AST 7523 ± 2146 U/L; Cr 8269 ± 1841 μmol/L; LDH 94467 ± 83432 U/L; TnT 0336 ± 0076 ng/ml) Profound hypothermia-induced SADR is an effective method for inducing cardiac arrest Our results indicate that inducing CA for 90 min (at 15 °C) is safer than doing so for 120 min Our results indicate that 120 min of CA at 15 °C is dangerous and can result in high mortality and severe neurological complications Further experimentation is needed to determine whether 120 min of CA at temperatures lower than 15 °C can lead to safe recovery

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A safety evaluation of profound hypothermia-induced suspended animation for delayed resuscitation at 90 or 120 min.

Introduction Diabetes mellitus (DM) is associated with physiological disorders such as delayed wound healing, diabetic retinopathy, diabetic nephropathy, and diabetic peripheral neuropathy (DPN). Over 50% of diabetic patients will develop DPN, characterized by motor dysfunction and impaired sensory nerve function. In a previous study, we have uncovered acrolein (ACR) as an upstream initiator which induced impaired glucose homeostasis and microvascular alterations in zebrafish. Whether ACR has specific effects on peripheral neurogenesis and mediates DPN, is still waiting for clarification. Methods To evaluate the function of ACR in peripheral nerve development, in vivo experiments were performed in Tg(hb9:GFP) zebrafish. In addition, a series of rescue experiments, metabolomics assessment, and bioinformatics analysis was performed aimed at identifying the molecular mechanisms behind ACR’s function and impaired neurogenesis. Results Impaired motor neuron development was confirmed in wild-type embryos treated with external ACR. ACR treated embryos displayed ferroptosis and reduction of several amino acids and increased glutathione (GSH). Furthermore, ferroptosis inducer caused similarly suppressed neurogenesis in zebrafish embryos, while anti-ACR treatment or ferroptosis inhibitor could successfully reverse the detrimental phenotypes of ACR on neurogenesis in zebrafish. Discussion Our data indicate that ACR could directly activate ferroptosis and impairs peripheral neurogenesis. The data strongly suggest ACR and activated ferroptosis as inducers and promising therapeutic targets for future DPN studies.

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Shu Li

Papers

Diallyl trisulfide ameliorates myocardial ischemia–reperfusion injury by reducing oxidative stress and endoplasmic reticulum stress-mediated apoptosis in type 1 diabetic rats: role of SIRT1 activation

A safety evaluation of profound hypothermia-induced suspended animation for delayed resuscitation at 90 or 120 min.

Acrolein-inducing ferroptosis contributes to impaired peripheral neurogenesis in zebrafish