Intranasal administration of DHED protects against exhaustive exercise-induced brain injury in rats

Methylene Blue Pretreatment Protects Against Repeated Neonatal Isoflurane Exposure-Induced Brain Injury and Memory Loss

Perioperative neurocognitive impairment (PND) is a common medical complication in the postoperative period. General anesthesia through volatile anesthetics poses a high risk of POCD. Moreover, the developing brain is especially vulnerable to anesthesia-induced neurotoxicity. Therefore, finding a practical approach to prevent or alleviate neonatal isoflurane (ISO) exposure-induced brain injury and cognitive decline is essential for reducing medical complications following major surgery during the early postnatal period. Using a repeated neonatal ISO exposure-induced PND rat model, we investigated the effects of methylene blue (MB) pretreatment on repeated neonatal isoflurane exposure-induced brain injury and memory loss. Intraperitoneal injection of low-dose MB (1 mg/kg) was conducted three times 24 h before each ISO exposure. The Barnes maze and novel objection test were conducted to assess learning and memory. Immunofluorescence staining, F-Jade C staining, TUNEL staining, and Western blot analysis were performed to determine mitochondrial fragmentation, neuronal injury, degeneration, and apoptosis. Evans blue extravasation assay, total antioxidant capacity assay, MDA assay kit, and related inflammatory assay kits were used to test blood-brain barrier (BBB) disruption, antioxidant capacity, and neuroinflammation. Behavioral tests revealed that MB pretreatment significantly ameliorated ISO exposure-induced cognitive deficits. In addition, MB pretreatment alleviates neuronal injury, apoptosis, and degeneration. Furthermore, the BBB integrity was preserved by MB pretreatment. Additional studies revealed that ISO-induced excessive mitochondrial fragmentation, oxidative stress, and neuroinflammation were significantly attenuated by MB pretreatment in the PND rat model. Our findings suggest that MB pretreatment alleviates ISO exposure-induced brain injury and memory loss for the first time, supporting MB pretreatment as a promising approach to protect the brain against neonatal ISO exposure-induced postoperative cognitive dysfunction.

Sheng Mai Yin shows anti-fatigue, anti-hypoxia and cardioprotective potential in an experimental joint model of fatigue and acute myocardial infarction

ETHNOPHARMACOLOGICAL RELEVANCE

Cardiovascular disease (CVD) and fatigue are two common diseases endangering human life and health that may interact and reinforce one another. Myocardial infarction survivors frequently experience fatigue, and acute myocardial infarction (AMI) is one of the most common cardiovascular diseases that cause fatigue-induced sudden death. Sheng Mai Yin (SMY), a Chinese medicine prescription, is traditionally used for the treatment of diabetes and cardiovascular disease, and has been demonstrated to reduce fatigue and safeguard cardiac function.

AIM OF THE STUDY

This study aims to investigate the effects and underlying mechanisms of SMY in treating fatigue and AMI.

MATERIALS AND METHODS

The pharmacological mechanisms of SMY in treating fatigue and AMI were predicted by bioinformatics and network pharmacology methods. After administering SMY at high, medium and low doses, the swimming time to exhaustion, hemoglobin level, serological parameters and hypoxia tolerance time were detected in C57BL/6N mice, and the left ventricular ejection fractions (LVEF), left ventricular fractional shortening (LVFS), grasp strength, cardiac histopathology, serological parameters and the expression of PINK1 and Parkin proteins were examined in Wistar rats.

RESULTS

371 core targets for SMY and 282 disease targets for fatigue and AMI were obtained using bioinformatics and network pharmacology methods. Enrichment analysis of target genes revealed that SMY might interfere with fatigue and AMI through biological processes such as mitochondrial autophagy, apoptosis, and oxidative stress. For in vivo experiments, SMY showed significant anti-fatigue and hypoxia tolerance effects in mice; It also improved the cardiac function and grasp strength, decreased their cardiac index, myocardial injury and fibrosis degree, and induced serological parameters levels and the expression of PTEN-induced putative kinase 1 (PINK1) and Parkin proteins in myocardium, suggesting that SMY may exert cardioprotective effects in a joint rat model of fatigue and AMI by inhibiting excessive mitochondrial autophagy.

CONCLUSION

This study revealed the anti-fatigue, anti-hypoxia and cardioprotective effects of SMY in a joint model of fatigue-AMI, and the pharmacological mechanism may be related to the inhibition of mitochondrial autophagy in cardiomyocytes through the PINK1/Parkin pathway. The discoveries may provide new ideas for the mechanism study of traditional Chinese medicine, especially complex prescriptions, in treating fatigue and AMI.

Neuroprotective Effect of Sub-lethal Hyperthermia Preconditioning in a Rat Model of Repeated Closed Head Injury

Repeated mild traumatic brain injury (rTBI), one of the most common forms of traumatic brain injury, is a worldwide severe public health concern. rTBI induces cumulative neuronal injury, neurological dysfunction, and cognitive deficits. Although there are clinical treatment methods, there is still an urgent need to develop preventive approaches for susceptible populations. Using a repeated closed head injury (rCHI) rat model, we interrogate the effect of sub-lethal hyperthermia preconditioning (SHP) on rCHI-induced neuronal injury and behavioral changes. Our study applied the repeated weight-drop model to induce the rCHI. According to the changes of heat shock protein 70 (HSP 70) in the cortex and hippocampus following a single SHP treatment in normal rats, the SHP was delivered to the rats 18 hours before rCHI. We found that HSP significantly alleviated rCHI-induced anxiety-like behaviors and impairments in motor abilities and spatial memory. SHP exerts significant neuroprotection against rCHI-induced neuronal damage, apoptosis, and neuroinflammation. Our findings support the potential use of SHP as a preventative approach for alleviating rCHI-induced brain damage.