Secondary Cerebellar Cortex Injury in Albino Male Rats after MCAO: A Histological and Biochemical Study

Electroacupuncture protects against the striatum of ischemia stroke by inhibiting the HMGB1/RAGE/p-JNK signaling pathways

The striatum (Str) is injured 20 min after permanent ischemic stroke, leading to neurological deficits. Here, we aimed to explore the effect of electroacupuncture (EA) on ischemic stroke and elucidate the possible underlying mechanism. Rat permanent middle cerebral artery occlusion (pMCAO) model, EA treatment, sham-EA (SEA) treatment, beam-balance test, hematoxylin and eosin (HE) staining, Nissl staining, immunofluorescence staining, and Western blot were used to investigate the role of EA in pMCAO. The results showed that balance ability and motor coordination were obviously injured after pMCAO. EA improved balance ability and motor coordination in pMCAO rats. EA reduced striatal injury by reducing the expression of high-mobility group box 1(HMGB1)/receptor for advanced glycation end products (RAGE)/phosphorylated C-Jun N-terminal kinase (p-JNK), whereas SEA did not. Thus, EA plays a neuroprotective role during pMCAO injury, which may be related to the inhibition of HMGB1/RAGE/p-JNK expression.

Protective effect of MitoTEMPO against cardiac dysfunction caused by ischemia-reperfusion: MCAO stroke model study

PURPOSE

Neurological impairments are the leading cause of post-stroke mortality, while stroke-related cardiovascular diseases rank second in significance. This study investigates the potential protective effects of MitoTEMPO (2,2,6,6-tetramethyl-4-[[2-(triphenylphosphonio) acetyl] amino]-1-piperidinyloxy, monochloride, monohydrate), a mitochondria-specific antioxidant, against cardiac and neurological complications following stroke. The objective is to assess whether MitoTEMPO can be utilized as a protective agent for individuals with a high risk of stroke.

MATERIALS AND METHODS

Seventeen-week-old male Wistar Albino rats were randomly assigned to three groups: SHAM, ischemia-reperfusion and MitoTEMPO + ischemia-reperfusion (MitoTEMPO injection 0.7 mg/kg/day for 14 days). The SHAM group underwent a sham operation, while the ischemia-reperfusion group underwent 1-h middle cerebral artery occlusion followed by three days of reperfusion. Afterwards, noninvasive thoracic electrical bioimpedance and electrocardiography measurements were taken, and sample collection was performed for histological and biochemical examinations.

RESULTS

Our thoracic electrical bioimpedance and electrocardiography findings demonstrated that MitoTEMPO exhibited a protective effect on most parameters affected by ischemia-reperfusion compared to the SHAM group. Furthermore, our biochemical and histological data revealed a significant protective effect of MitoTEMPO against oxidative damage.

CONCLUSIONS

The findings suggest that both ischemia-reperfusion-induced cardiovascular abnormalities and the protective effect of MitoTEMPO may involve G-protein coupled receptor-mediated signaling mechanisms. This study was conducted with limitations including a single gender, a uniform age group, a specific stroke model limited to middle cerebral artery, and pre-scheduled only one ischemia-reperfusion period. In future studies, addressing these limitations may enable the implementation of preventive measures for individuals at high risk of stroke.

Regulatory Effect of Electroacupuncture on Hypothalamic Serotonin and its Receptor in Rats with Cerebral Ischemia

BACKGROUND

Previous studies have shown that the neurological damage caused by middle cerebral artery occlusion (MCAO) is not only limited to local infarction but can also cause secondary damage in distant sites, such as the hypothalamus. 5-hydroxytryptamine (5-HT)/ 5-HT transporter (5-HTT) and 5-HT receptor 2A (5-HT2A) are important in the treatment of cerebrovascular diseases.

OBJECTIVE

This study aimed to study the effect of electroacupuncture (EA) on the expression of 5- HT, 5-HTT, and 5-HT2A in the hypothalamus of rats with ischemic brain injury and to explore the protective effect and potential mechanism of EA on the secondary injury of cerebral ischemia.

METHODS

Sprague-Dawley (SD) rats were randomly divided into three groups: sham group, model group, and EA group. The permanent middle cerebral artery occlusion (pMCAO) method was used to induce ischemic stroke in rats. In the EA group, the Baihui (GV20) and Zusanli (ST36) points were selected for treatment, which was administered once per day for two consecutive weeks. The neuroprotective effect of EA was evaluated by nerve defect function scores and Nissl staining. The content of 5-HT in hypothalamus was detected by enzyme linked immunosorbent assay (ELISA), and the expression of 5-HTT and 5-HT2A were detected by Western blot.

RESULTS

Compared with that in the sham group, the nerve defect function score in the model group rats was significantly increased, the hypothalamus tissue showed obvious nerve damage, the levels of 5-HT and the expression of 5-HTT were significantly reduced, and the expression of 5-HT2A was significantly increased. After 2 weeks of EA treatment, the nerve defect function scores of pMCAO rats were significantly reduced, the hypothalamic nerve injury was significantly reduced, the levels of 5-HT and the expression of 5-HTT were significantly increased, and the expression of 5-HT2A was significantly decreased.

CONCLUSION

EA has a certain therapeutic effect on hypothalamic injury secondary to permanent cerebral ischemia, and its potential mechanism may be closely related to the upregulation of 5-HT and 5-HTT expression and the downregulation of 5-HT2A expression.

Preclinical Evidence of Paeoniflorin Effectiveness for the Management of Cerebral Ischemia/Reperfusion Injury: A Systematic Review and Meta-Analysis

Background: Vessel recanalization is the main treatment for ischemic stroke; however, not all patients benefit from it. This lack of treatment benefit is related to the accompanying ischemia-reperfusion (I/R) injury. Therefore, neuroprotective therapy for I/R Injury needs to be further studied. Paeonia lactiflora Pall. is a commonly used for ischemic stroke management in traditional Chinese medicine; its main active ingredient is paeoniflorin (PF). We aimed to determine the PF’s effects and the underlying mechanisms in instances of cerebral I/R injury.

Methods: We searched seven databases from their inception to July 2021.SYRCLE’s risk of bias tool was used to assess methodological quality. Review Manager 5.3 and STATA 12.0 software were used for meta-analysis.

Results: Thirteen studies, including 282 animals overall, were selected. The meta-analyses showed compared to control treatment, PF significantly reduced neurological severity scores, cerebral infarction size, and brain water content (p = 0.000). In the PF treatment groups, the apoptosis cells and levels of inflammatory factors (IL-1β) decreased compared to those in the control groups (p = 0.000).

Conclusion: Our results suggest that PF is a promising therapeutic for cerebral I/R injury management. However, to evaluate the effects and safety of PF in a more accurate manner, additional preclinical studies are necessary.