Quercetin alleviates microglial-induced inflammation after traumatic brain injury via the PGC-1α/Nrf2 pathway dependent on HDAC3 inhibition.

Inflammation and neuronal apoptosis play a key role in traumatic brain injury (TBI). Quercetin (Que) has been shown to exhibit a neuroprotective effect after TBI, but the underlying molecular mechanism remains unclear. In this study, We established a weight-drop mouse model to illustrate the effects of Que on microglial-induced inflammation in TBI. Mice were divided into four groups: the Sham group, TBI group, TBI+vehicle group, and TBI+Que group. The TBI+Que group was treated with Que 30 min after TBI. Brain water content, neurological score, and neuronal apoptosis were measured. Western blotting, TUNEL staining, Nissl staining, quantitative polymerase chain reaction, and immunofluorescence staining were performed to assess the activation of the PGC-1α/Nrf2 pathway and nuclear translocation of HDAC3 with Que treatment. The results showed that Que administration alleviated TBI-induced neurobehavioral deficits, encephaledema, and neuron apoptosis. Que also restrained TBI-induced microglial activity and the subsequent expression of the inflammatory factor in the contusion cortex. Moreover, Que treatment activated the PGC-1α/Nrf2 pathway, attributable to the inhibition of HDAC3 translocation to the nucleus. Overall, these results reveal the role of Que in protecting against TBI-induced neuroinflammation and promoting neurological functional recovery, which is achieved through the negative regulation of HDAC3.

Sinomenine Protects against Early Brain Injury by Inhibiting Microglial Inflammatory Response via Nrf2-Dependent Pathway after Subarachnoid Hemorrhage.

Microglial activation and sustained inflammation plays an important role in the processes of early brain injury (EBI) after subarachnoid hemorrhage (SAH). Sinomenine (SIN) has been demonstrated to have neuroprotective effects in the traumatic brain injury (TBI) model. However, the role of SIN in SAH-induced EBI and its latent mechanisms remain unclear. This study was carried out to explore the role of SIN on SAH-induced EBI and its effects on the microglial inflammatory response following SAH. In this study, a model of SAH in rats was established. Modified neurological severity scores (mNSS), encephaledema, and Nissl staining were employed to determine the effects of SIN. Western blot and immunofluorescence analysis were performed to evaluate nuclear factor erythroid 2-related factor 2 (Nrf2) expression. Nrf2-related downstream proteins, including heme oxygenase-1 (HO-1) and quinine oxidoreductase-1 (NQO-1), were detected with immunohistochemistry analyses and Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR). Microglia activation and associated inflammatory factors, factor-kappa B (NF-κB), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6), were assessed after SAH. The results showed that SIN administration improved neurobehavior function, and attenuated neural apoptosis and brain edema after SAH. In addition, SIN inhibited microglial action and the subsequent inflammatory response after SAH through the upregulated expression of HO-1 and NQO-1 via activation of the Nrf2 pathway. These results demonstrated that SIN supplementation provided protection against SAH-induced neuronal apoptosis by microglial inflammatory response regulation and possible involvement of the Nrf2 pathway.

Sinomenine reduces neuronal cell apoptosis in mice after traumatic brain injury via its effect on mitochondrial pathway.

BACKGROUND: Sinomenine (SIN) has been shown to have protective effects against brain damage following traumatic brain injury (TBI). However, the mechanisms and its role in these effects remain unclear. This study was conducted to investigate the potential mechanisms of the protective effects of SIN. METHODS: The weight-drop model of TBI in Institute of Cancer Research (ICR) mice were treated with SIN or a vehicle via intraperitoneal administration 30 min after TBI. All mice were euthanized 24 h after TBI and after neurological scoring, a series of tests were performed, including brain water content and neuronal cell death in the cerebral cortex. RESULTS: The level of cytochrome c (Cyt c), malondialdehyde (MDA), glutathione peroxidase (GPx) and superoxide dismutase 1 (SOD) were restored to some degree following the SIN treatment. The SIN treatment significantly decreased caspase-3 expression and reduced the number of positive cells by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and improved the survival of neuronal cells. Additionally, the pretreatment levels of MDA were restored, while Bax translocation to mitochondria and Cyt c release into the cytosol were reduced by the SIN treatment. CONCLUSION: SIN protected neuronal cells by protecting them against apoptosis via mechanisms that involve the mitochondria following TBI.

[Effects of puerarin on the vascular active factor related to cerebral vasospasm after aneurysm subarachnoid hemorrhage].

OBJECTIVE: To investigate the effects and possible mechanisms of puerarin on the vascular active factors correlated to cerebral vasospasm (CVS) after aneurysm subarachnoid hemorrhage (aSAH). METHODS: Fifty-four patients with aSAH were randomly assigned to the puerarin group (30 cases) and the control group (24 cases) by lot. On the basis of routine treatment, the patients in the puerarin group were intravenously dripped with 0.5 g puerarin by adding in 250 mL glucose injection once daily. The injection was given starting from the 3rd day of the disease course, for 14 successive days. The plasma levels of nitric oxide (NO), endothelin-1 (ET-1), thromboxane B, (TXB2), 6-Keto-prostaglandin F1alpha (6-K-PGF1alpha) were compared between the two groups pre- and post-therapy. The incidence of cerebral vasospasm (CVS) was observed using transcranial Doppler (TCD). The Glasgow outcome scale (GOS) were compared at discharge between the two groups. RESULTS: Compared with the control group, the plasma levels of NO, ET-1, and 6-K-PGF1alpha increased in the puerarin group (P < 0. 05), the TXB2 level decreased (P < 0.05), the incidence of CVS decreased (P < 0.05), the mean MCA velocity increased (P < 0.05), and the GOS at discharge increased (P < 0.05). CONCLUSIONS: Puerarin is an effective agent for the prophylaxis and treatment of the CVS in patients after aSAH. Moreover, it can improve the prognosis. The mechanism might be correlated with improving the levels of the vascular active factors, i.e., increasing the plasma levels of NO and PGl2, decreasing TXA, in plasma, increasing the cerebral blood flow, and improving cerebral perfusion.

The effect of lentivirus-mediated TH and GDNF genetic engineering mesenchymal stem cells on Parkinson's disease rat model.

This study was designed to assess the potential therapeutic efficacy of gene-modified mesenchymal stem cells (MSCs), MSCs-TH and MSCs-GDNF, in PD rats. Fifty-nine PD rat models were divided into five groups and then the gene-modified MSCs were transplanted into the striatum of rats according to the design. Apomorphine-induced rotational behavior in rats was observed weekly; rats which received both MSCs-TH and MSCs-GDNF showed the most significant improvement compared with those in other groups (P < 0.01). Three weeks later, immunohistochemistry analysis found TH-positive cells and GDNF-positive cells in striatal. Eight weeks later, PD rats were killed. HPLC and ELISA results showed DA and GDNF content in striatum of rats which received both MSCs-TH, and MSCs-GDNF was considerably higher compared with those of other groups (P < 0.01),respectively. In conclusion, our results suggest that combined transplantation of MSCs expressing TH and GDNF can lead to remarkable therapeutic effects in a rat model of PD.