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Background: Cardiomyocyte apoptosis plays a vital role in myocardial ischemia-reperfusion (MI/R) injury; however, the role of beclin1 (BECN1) remains unclear. This study aimed at revealing the function of BECN1 during cardiomyocyte apoptosis after MI/R injury., Methods: In vivo, TTC and Evan's blue double staining was applied to verify the gross morphological alteration in both wild type (WT) mice and BECN1 transgene mice (BECN1-TG), and TUNEL staining and western blot were adopted to evaluate the cardiomyocyte apoptosis. In vitro, a hypoxia/reoxygenation (H/R) model was established in H9c2 cells to simulate MI/R injury. Proteomics analysis was preformed to verify if apoptosis occurs in the H/R cellular model. And apoptosis factors, RIPK1, Caspase-1, Caspase-3, and cleaved Caspase-3, were investigated using western bolting. In addition, the mRNA level were verified using RT-PCR. To further investigate the protein interactions small interfering RNA and lentiviral transfection were used. To continue investigate the protein interactions, immunofluorescence and coimmunoprecipitation were applied., Results: Morphologically, BECN1 significantly attenuated the apoptosis from TTC-Evan's staining, TUNEL, and cardiac tissue western blot. After H/R, a RIPK1-induced complex (complex II) containing RIPK1, Caspase-8, and FADD was formed. Thereafter, cleaved Caspase-3 was activated, and myocyte apoptosis occurred. However, BECN1 decreased the expression of RIPK1, Caspase-8, and FADD. Nevertheless, BECN1 overexpression increased RIPK1 ubiquitination before apoptosis by inhibiting OTUD1., Conclusions: BECN1 regulates FADD/RIPK1/Caspase-8 complex formation via RIPK1 ubiquitination by downregulating OTUD1 in C-Caspase-3-induced myocyte apoptosis after MI/R injury. Therefore, BECN1 can function as a cardioprotective candidate., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Hyperglycemia-induced neuroinflammation significantly contributes to diabetic neuropathic pain (DNP), but the underlying mechanisms remain unclear., Objective: To investigate the role of Sirt3, a mitochondrial deacetylase, in hyperglycemia-induced neuroinflammation and DNP and to explore potential therapeutic interventions., Method and Results: Here, we found that Sirt3 was downregulated in spinal dorsal horn (SDH) of diabetic mice by RNA-sequencing, which was further confirmed at the mRNA and protein level. Sirt3 deficiency exacerbated hyperglycemia-induced neuroinflammation and DNP by enhancing microglial aerobic glycolysis in vivo and in vitro. Overexpression of Sirt3 in microglia alleviated inflammation by reducing aerobic glycolysis. Mechanistically, high-glucose stimulation activated Akt, which phosphorylates and inactivates FoxO1. The inactivation of FoxO1 diminished the transcription of Sirt3. Besides that, we also found that hyperglycemia induced Sirt3 degradation via the mitophagy-lysosomal pathway. Blocking Akt activation by GSK69093 or metformin rescued the degradation of Sirt3 protein and transcription inhibition of Sirt3 mRNA, which substantially diminished hyperglycemia-induced inflammation. Metformin in vivo treatment alleviated neuroinflammation and diabetic neuropathic pain by rescuing hyperglycemia-induced Sirt3 downregulation., Conclusion: Hyperglycemia induces metabolic reprogramming and inflammatory activation in microglia through the regulation of Sirt3 transcription and degradation. This novel mechanism identifies Sirt3 as a potential drug target for treating DNP., (© 2024 The Author(s). CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd.)

Oligodendrocytes and astrocytes are metabolically coupled to neuronal compartments. Pyruvate and lactate can shuttle between glial cells and axons via monocarboxylate transporters. However, lactate can only be synthesized or used in metabolic reactions with the help of lactate dehydrogenase (LDH), a tetramer of LDHA and LDHB subunits in varying compositions. Here we show that mice with a cell type-specific disruption of both Ldha and Ldhb genes in oligodendrocytes lack a pathological phenotype that would be indicative of oligodendroglial dysfunctions or lack of axonal metabolic support. Indeed, when combining immunohistochemical, electron microscopical, and in situ hybridization analyses in adult mice, we found that the vast majority of mature oligodendrocytes lack detectable expression of LDH. Even in neurodegenerative disease models and in mice under metabolic stress LDH was not increased. In contrast, at early development and in the remyelinating brain, LDHA was readily detectable in immature oligodendrocytes. Interestingly, by immunoelectron microscopy LDHA was particularly enriched at gap junctions formed between adjacent astrocytes and at junctions between astrocytes and oligodendrocytes. Our data suggest that oligodendrocytes metabolize lactate during development and remyelination. In contrast, for metabolic support of axons mature oligodendrocytes may export their own glycolysis products as pyruvate rather than lactate. Lacking LDH, these oligodendrocytes can also "funnel" lactate through their "myelinic" channels between gap junction-coupled astrocytes and axons without metabolizing it. We suggest a working model, in which the unequal cellular distribution of LDH in white matter tracts facilitates a rapid and efficient transport of glycolysis products among glial and axonal compartments., (© 2024 The Authors. GLIA published by Wiley Periodicals LLC.)

Ischemic stroke involves various pathological processes, among which ferroptosis is crucial. Previous studies by our group have indicated that electroacupuncture (EA) mitigates ferroptosis after ischemic stroke; however, the precise mechanism underlying this effect remains unclear. In the present study, we developed a rat model of middle cerebral artery occlusion/reperfusion. We chose the main acupoint of the treatment methods of the "Awakening and Opening of the Brain". Rats' neurological function and motor coordination were evaluated by neurological function score and the rotarod test, respectively, and the volume of cerebral infarction was analyzed by 2,3,5-triphenyltetrazolium chloride Staining. The cerebrovascular conditions were visualized by time-of-flight magentic resonance angiography. In addition, we detected changes in lipid peroxidation and endogenous antioxidant activity by measuring the malondialdehyde, glutathione, superoxide dismutase activities, glutathione/oxidized glutathione and reduced nicotinamide adenine dinucleotide phosphate/oxidized nicotinamide adenine dinucleotide phosphate ratios. Inductively coupled plasma-mass spectrometry, western blot, reverse transcription-polymerase chain reaction, fluoro-jade B staining, immunofluorescence analysis, and transmission electron microscopy were utilized to examine the influence of EA. The results indicate that EA treatment was effective in reversing neurological impairment, neuronal damage, and protecting mitochondrial morphology and decreasing the cerebral infarct volume in the middle cerebral artery occlusion/reperfusion rat model. EA reduced iron levels, inhibited lipid peroxidation, increased endogenous antioxidant activity, modulated the expression of several ferroptosis-related proteins, and promoted nuclear factor-E2-related factor 2 (Nrf2) nuclear translocation. However, the protective effect of EA was hindered by the Nrf2 inhibitor ML385. These findings suggest that EA can suppress ferroptosis and decrease damage caused by cerebral ischemia/reperfusion by activating Nrf2 and increasing the protein expression of solute carrier family 7 member 11 and glutathione peroxidase 4., (© 2024. The Author(s).)