Electroacupuncture Pretreatment Alleviates Cerebral Ischemia-Reperfusion Injury by Regulating Mitophagy via mTOR-ULK1/FUNDC1 Axis in Rats

MAM-mediated mitophagy and endoplasmic reticulum stress: the hidden regulators of ischemic stroke

Ischemic stroke (IS) is the predominant subtype of stroke and a leading contributor to global mortality. The mitochondrial-associated endoplasmic reticulum membrane (MAM) is a specialized region that facilitates communication between the endoplasmic reticulum and mitochondria, and has been extensively investigated in the context of neurodegenerative diseases. Nevertheless, its precise involvement in IS remains elusive. This literature review elucidates the intricate involvement of MAM in mitophagy and endoplasmic reticulum stress during IS. PINK1, FUNDC1, Beclin1, and Mfn2 are highly concentrated in the MAM and play a crucial role in regulating mitochondrial autophagy. GRP78, IRE1, PERK, and Sig-1R participate in the unfolded protein response (UPR) within the MAM, regulating endoplasmic reticulum stress during IS. Hence, the diverse molecules on MAM operate independently and interact with each other, collectively contributing to the pathogenesis of IS as the covert orchestrator.

Overview of mechanism of electroacupuncture pretreatment for prevention and treatment of cardiovascular and cerebrovascular diseases

Cardio-cerebrovascular disease (CCVD) is a serious threat to huma strategy to prevent the occurrence and development of disease by giving electroacupuncture intervention before the disease occurs. EAP has been shown in many preclinical studies to relieve ischemic symptoms and improve damage from ischemia-reperfusion, with no comprehensive review of its mechanisms in cardiovascular disease yet. In this paper, we first systematically discussed the meridian and acupoint selection law of EAP for CCVD and focused on the progress of the mechanism of action of EAP for the prevention and treatment of CCVD. As a result, in preclinical studies, AMI and MCAO models are commonly used to simulate ischemic injury in CCVD, while MIRI and CI/RI models are used to simulate reperfusion injury caused by blood flow recovery after focal tissue ischemia. According to the meridian matching rules of EAP for CCVD, PC6 in the pericardial meridian is the most commonly used acupoint in cardiovascular diseases, while GV20 in the Du meridian is the most commonly used acupoint in cerebrovascular diseases. In terms of intervention parameters, EAP intervention generally lasts for 30 min, with acupuncture depths mostly between 1.5 and 5 mm, stimulation intensities mostly at 1 mA, and commonly used frequencies being low frequencies. In terms of molecular mechanisms, the key pathways of EAP in preventing and treating cardiovascular and cerebrovascular diseases are partially similar. EAP can play a protective role in cardiovascular and cerebrovascular diseases by promoting autophagy, regulating Ca2+ overload, and promoting vascular regeneration through anti-inflammatory reactions, antioxidant stress, and anti-apoptosis. Of course, both pathways involved have their corresponding specificities. When using EAP to prevent and treat cardiovascular diseases, it involves the metabolic pathway of glutamate, while when using EAP to prevent and treat cerebrovascular diseases, it involves the homeostasis of the blood-brain barrier and the release of neurotransmitters and nutritional factors. I hope these data can provide experimental basis and reference for the clinical promotion and application of EAP in CCVD treatment.

Natural products: A potential immunomodulators against inflammatory-related diseases

The incidence and prevalence of inflammatory-related diseases (IRDs) are increasing worldwide. Current approved treatments for IRDs in the clinic are combat against inhibiting the pro-inflammatory cytokines. Though significant development in the treatment in the IRDs has been achieved, the severe side effects and inefficiency of currently practicing treatments are endless challenge. Drug discovery from natural sources is efficacious over a resurgence and also natural products are leading than the synthetic molecules in both clinical trials and market. The use of natural products against IRDs is a conventional therapeutic approach since it is a reservoir of unique structural chemistry, accessibility and bioactivities with reduced side effects and low toxicity. In this review, we discuss the cause of IRDs, treatment of options for IRDs and the impact and adverse effects of currently practicing clinical drugs. As well, the significant role of natural products against various IRDs, the limitations in the clinical development of natural products and thus pave the way for development of natural products as immunomodulators against IRDs are also discussed.

Acupuncture for stroke: A bibliometric analysis of global research from 2000 to 2022

Objective

This study aimed to explore the global and future research trends in acupuncture interventions for stroke between 2000 and 2022 using bibliometric analysis.

Method

A bibliometric analysis of literature from 2000 to 2022 in the Web of Science Core Collection was conducted in this study. The analysis utilized CiteSpace, VOSviewer, and Scimago Graphica software to identify the major contributors to publications, including authors, countries, institutions, journals, references, and keywords.

Results

The bibliometric analysis yielded a total of 860 publications. There was a gradual increase in the number of publications over the study period. China published the most articles. Evidence-Based Complementary and Alternative Medicine was the journal with the greatest number of publications. The most frequently used keywords were "acupuncture," "stroke," and "electroacupuncture."

Conclusion

These analysis uncovers the research trends in acupuncture for stroke spanning 2000 to 2022 and points to prospective research frontiers. This study provides a deeper and more thorough understanding of the connotations of acupuncture for stroke and guidance and support for future research in this field.

Neuroprotective effects of galectin‑1 on cerebral ischemia/reperfusion injury by regulating oxidative stress

Oxidative stress contributes to the pathology of cerebral ischemia/reperfusion (I/R) injury. Galectin-1 has shown an anti-oxidative stress effect. The present study investigated whether this anti-oxidative stress effect can account for the neuroprotective actions of galectin-1 induced by cerebral I/R injury. A cerebral I/R injury model was created in C57Bl/6 mice by transient occlusion of the middle cerebral artery, after which the mice were treated with galectin-1 for 3 days. Infarct volumes were measured. A rotarod test and neurological deficit score assessment was performed to evaluate the neurological deficits. Oxidative stress was evaluated by measuring the levels of reactive oxygen species (ROS) and lipid peroxidation malondialdehyde (MDA), while the anti-oxidative stress status was assessed by measuring molecules such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidation enzyme (GSH-Px) in the ischemic cerebral hemisphere of mice. The inflammatory cytokines, including Interleukin 1 (IL-1), IL-6 and tumor necrosis factor alpha (TNF-α) were measured, and the expression of microglia was evaluated by immunohistochemistry in the ischemic cerebral hemisphere of mice. Galectin-1 treatment ameliorated neurological deficits and reduced infarct volumes in the mice model with cerebral I/R injury. Moreover, it was demonstrated that galectin-1 can significantly alleviate cerebral I/R injury in the ischemic cerebral hemisphere by decreasing the production of ROS and MDA, but increasing the production of CAT, SOD and GSH-Px. Galectin-1 treatment decreased microglia expression, and IL-1, IL-6 and TNF-α levels in the ischemic cerebral hemisphere of mice. Galectin-1 could improve the outcome of cerebral I/R injury by alleviating oxidative stress. Moreover, the neuroprotective effect of galectin-1 in cerebral ischemia could be related to its anti-oxidative stress effect.

Targeting neuronal mitophagy in ischemic stroke: an update

Cerebral ischemia is a neurological disorder associated with complex pathological mechanisms, including autophagic degradation of neuronal mitochondria, or termed mitophagy, following ischemic events. Despite being well-documented, the cellular and molecular mechanisms underlying the regulation of neuronal mitophagy remain unknown. So far, the evidence suggests neuronal autophagy and mitophagy are separately regulated in ischemic neurons, the latter being more likely activated by reperfusional injury. Specifically, given the polarized morphology of neurons, mitophagy is regulated by different neuronal compartments, with axonal mitochondria being degraded by autophagy in the cell body following ischemia-reperfusion insult. A variety of molecules have been associated with neuronal adaptation to ischemia, including PTEN-induced kinase 1, Parkin, BCL2 and adenovirus E1B 19-kDa-interacting protein 3 (Bnip3), Bnip3-like (Bnip3l) and FUN14 domain-containing 1. Moreover, it is still controversial whether mitophagy protects against or instead aggravates ischemic brain injury. Here, we review recent studies on this topic and provide an updated overview of the role and regulation of mitophagy during ischemic events.

Autophagy regulates inflammation in intracerebral hemorrhage: Enemy or friend?

Intracerebral hemorrhage (ICH) is the second-largest stroke subtype and has a high mortality and disability rate. Secondary brain injury (SBI) is delayed after ICH. The main contributors to SBI are inflammation, oxidative stress, and excitotoxicity. Harmful substances from blood and hemolysis, such as hemoglobin, thrombin, and iron, induce SBI. When cells suffer stress, a critical protective mechanism called "autophagy" help to maintain the homeostasis of damaged cells, remove harmful substances or damaged organelles, and recycle them. Autophagy plays a critical role in the pathology of ICH, and its function remains controversial. Several lines of evidence demonstrate a pro-survival role for autophagy in ICH by facilitating the removal of damaged proteins and organelles. However, many studies have found that heme and iron can aggravate SBI by enhancing autophagy. Autophagy and inflammation are essential culprits in the progression of brain injury. It is a fascinating hypothesis that autophagy regulates inflammation in ICH-induced SBI. Autophagy could degrade and clear pro-IL-1β and apoptosis-associated speck-like protein containing a CARD (ASC) to antagonize NLRP3-mediated inflammation. In addition, mitophagy can remove endogenous activators of inflammasomes, such as reactive oxygen species (ROS), inflammatory components, and cytokines, in damaged mitochondria. However, many studies support the idea that autophagy activates microglia and aggravates microglial inflammation via the toll-like receptor 4 (TLR4) pathway. In addition, autophagy can promote ICH-induced SBI through inflammasome-dependent NLRP6-mediated inflammation. Moreover, some resident cells in the brain are involved in autophagy in regulating inflammation after ICH. Some compounds or therapeutic targets that regulate inflammation by autophagy may represent promising candidates for the treatment of ICH-induced SBI. In conclusion, the mutual regulation of autophagy and inflammation in ICH is worth exploring. The control of inflammation by autophagy will hopefully prove to be an essential treatment target for ICH.

Traditional Chinese medicine in treating ischemic stroke by modulating mitochondria: A comprehensive overview of experimental studies

Ischemic stroke has been a prominent focus of scientific investigation owing to its high prevalence, complex pathogenesis, and difficulties in treatment. Mitochondria play an important role in cellular energy homeostasis and are involved in neuronal death following ischemic stroke. Hence, maintaining mitochondrial function is critical for neuronal survival and neurological improvement in ischemic stroke, and mitochondria are key therapeutic targets in cerebral stroke research. With the benefits of high efficacy, low cost, and high safety, traditional Chinese medicine (TCM) has great advantages in preventing and treating ischemic stroke. Accumulating studies have explored the effect of TCM in preventing and treating ischemic stroke from the perspective of regulating mitochondrial structure and function. In this review, we discuss the molecular mechanisms by which mitochondria are involved in ischemic stroke. Furthermore, we summarized the current advances in TCM in preventing and treating ischemic stroke by modulating mitochondria. We aimed to provide a new perspective and enlightenment for TCM in the prevention and treatment of ischemic stroke by modulating mitochondria.

Electroacupuncture Activates Neuroplasticity in the Motor Cortex and Corticospinal Tract via the mTOR Pathway in a Rat P-MCAO Model

Electroacupuncture (EA) combines traditional Chinese medicine acupuncture theory with modern scientific technology. It is a promising therapy for the treatment of cerebrovascular diseases such as cerebral infarction. A large number of clinical studies have shown that EA promotes recovery of neurological function after cerebral infarction, however, the underlying mechanisms behind its effects remain unclear. We tested whether EA stimulation of the Zusanli (ST36) and Neiguan (PC6) acupoints activates neuroplasticity in rats with ischemic stroke and whether this involves the regulation of axonal regeneration through the mTOR pathway. 24 h after permanent middle cerebral artery occlusion (p-MCAO) in rats, EA treatment was started for 20 min, daily, for 14 days. We found that EA significantly reduced Modified Neurological Severity Scores (mNSS), cerebral infarct volume, and apoptosis of neuronal cells. EA also significantly increased the expression of the neuroplasticity-associated proteins GAP-43 and SYN and upregulated the phosphorylation levels of AKT, mTOR, S6, and PTEN to promote CST axon sprouting in the spinal cord at C1-C4 levels. The positive effects of EA were blocked by the administration of the mTOR inhibitor Rapamycin. In short, we found that EA of the Zusanli (ST36) and Neiguan (PC6) acupoints in p-MCAO rats induced neuroprotective and neuroplastic effects by regulating the mTOR signaling pathway. It promoted neuroplasticity activated by axon regeneration in the contralateral cortex and corticospinal tract. Activation of such endogenous remodeling is conducive to neurological recovery and may help explain the positive clinical effects seen in patients with infarcts.

The multi-faced role of FUNDC1 in mitochondrial events and human diseases

Mitophagy plays a vital role in the selective elimination of dysfunctional and unwanted mitochondria. As a receptor of mitophagy, FUN14 domain containing 1 (FUNDC1) is attracting considerably critical attention. FUNDC1 is involved in the mitochondria fission, the clearance of unfolded protein, iron metabolism in mitochondria, and the crosstalk between mitochondria and endoplasmic reticulum besides mitophagy. Studies have demonstrated that FUNDC1 is associated with the progression of ischemic disease, cancer, and metabolic disease. In this review, we systematically examine the recent advancements in FUNDC1 and the implications of this protein in health and disease.