Huanglian Jiedu decoction alleviates ischemia-induced cerebral injury in rats by mitigating NET formation and activiting GABAergic synapses.

Huanglian Jiedu decoction (HLJD) has been used to treat ischemic stroke in clinic. However, the detailed protective mechanisms of HLJD on ischemic stroke have yet to be elucidated. The aim of this study is to elucidate the underlying pharmacological mechanisms of HLJD based on the inhibition of neuroinflammation and the amelioration of nerve cell damage. A middle cerebral artery occlusion reperfusion (MCAO/R) model was established in rats and received HLJD treatment. Effects of HLJD on neurological function was assessed based on Bederson's score, postural reflex test and asymmetry score. 2, 3, 5-Triphenyltetrazolium chloride (TTC) staining, Hematein and eosin (HE) and Nissl staining were used to observe the pathological changes in brain. Then, transcriptomics was used to screen the differential genes in brain tissue in MCAO/R model rats following HLJD intervention. Subsequently, the effects of HLJD on neutrophil extracellular trap (NET) formation-related neuroinflammation, gamma-aminobutyric acid (GABA)ergic synapse activation, nerve cell damage and proliferation were validated using immunofluorescence, western blot and enzyme-linked immunosorbent assay (ELISA). Our results showed that HLJD intervention reduced the Bederson's score, postural reflex test score and asymmetry score in MCAO/R model rats. Pathological staining indicated that HLJD treatment decreased the cerebral infarction area, mitigated neuronal damage and increased the numbers of Nissl bodies. Transcriptomics suggested that HLJD affected 435 genes in MCAO/R rats. Among them, several genes involving in NET formation and GABAergic synapses pathways were dysregulated. Subsequent experimental validation showed that HLJD reduced the MPO+CitH3+ positive expression area, reduced the protein expression of PAD4, p-P38/P38, p-ERK/ERK and decreased the levels of IL-1β, IL-6 and TNF-α, reversed the increase of Iba1+TLR4+, Iba1+p65+ and Iba1+NLRP3+ positive expression area in brain. Moreover, HLJD increased GABA levels, elevated the protein expression of GABRG1 and GAT3, decreased the TUNEL positive expression area and increased the Ki67 positive expression area in brain. HLJD intervention exerts a multifaceted positive impact on ischemia-induced cerebral injury in MCAO/R rats. This intervention effectively inhibits neuroinflammation by mitigating NET formation, and concurrently improves nerve cell damage and fosters nerve cell proliferation through activating GABAergic synapses.

Cui Y ，Cui M ，Wang L ，Wang N ，Chen Y ，Lv S ，Zhang L ，Chen C ，Yang Y ，Wang F ，Wang L ，Cui H ... -  《-》

GJ-4 ameliorates memory impairment in focal cerebral ischemia/reperfusion of rats via inhibiting JAK2/STAT1-mediated neuroinflammation.

Gardenia jasminoides J. Ellis (Fructus Gardenia) is a traditional Chinese medicine with diverse pharmacological functions, such as anti-inflammation, anti-depression, as well as improvement of cognition and ischemia brain injury. GJ-4 is a natural extract from Gardenia jasminoides J. Ellis (Fructus Gardenia) and has been proved to improve memory impairment in Alzheimer's disease (AD) mouse model in our previous studies. This study aimed to evaluate the therapeutic effects of GJ-4 on vascular dementia (VD) and explore the potential mechanisms. In our experiment, a focal cerebral ischemia and reperfusion rat model was successfully developed by the middle cerebral artery occlusion and reperfusion (MCAO/R). GJ-4 (10 mg/kg, 25 mg/kg, 50 mg/kg) and nimodipine (10 mg/kg) were orally administered to rats once a day for consecutive 12 days. Learning and memory behavioral performance was assayed by step-down test and Morris water maze test. The neurological scoring test was performed to evaluate the neurological function of rats. 2,3,5-Triphenyltetrazolium chloride (TTC) staining and Nissl staining were respectively employed to determine the infarct condition and neuronal injury of the brain. Iba1 immunohistochemistry was used to show the activation of microglia. Moreover, the synaptic damage and inflammatory level were detected by Western blot. GJ-4 could significantly improve memory impairment, cerebral infraction, as well as neurological deficits of VD rats induced by MCAO/R. Further research indicated VD-induced neuronal injury was alleviated by GJ-4. In addition, GJ-4 could protect synapse of VD rats by upregulating synaptophysin (SYP) expression, post synaptic density 95 protein (PSD95) expression, and downregulating N-Methyl-D-Aspartate receptor 1 (NMDAR1) expression. Subsequent investigation of the underlying mechanisms identified that GJ-4 could suppress neuroinflammatory responses, supported by inhibited activation of microglia and reduced expression of inflammatory proteins, which ultimately exerted neuroprotective effects on VD. Further mechanistic study indicated that janus kinase 2 (JAK2)/signal transducer and activator of transcription 1 (STAT1) pathway was inhibited by GJ-4 treatment. These results suggested that GJ-4 might serve as a potential drug to improve VD. In addition, our study indicated that inhibition of neuroinflammation might be a promising target to treat VD.

Liu H ，Zhang Z ，Zang C ，Wang L ，Yang H ，Sheng C ，Shang J ，Zhao Z ，Yuan F ，Yu Y ，Yao X ，Bao X ，Zhang D ... -  《-》

Mailuo Shutong pills inhibit neuroinflammation by regulating glucose metabolism disorders to protect mice from cerebral ischemia-reperfusion injury.

Mailuo Shutong Pill (MLST), a traditional Chinese medicine (TCM), has been widely used for clearing heat and detoxifying, eliminating stasis and dredging meridians, dispelling dampness and diminishing swelling. Earlier study found that MLST could improve cerebral ischemic-reperfusion injury, however, the potential mechanism has not been well evaluated. In this study, a well established and widely used mice model of middle cerebral artery occlusion/reperfusion (MCAO/R) was preformed to evaluate the protective function of MLST on cerebral ischemic-reperfusion injury and further discuss the potential pharmacological mechanisms. Chemical profiling of MLST was analyzed based on Ultra-high-performance liquid chromatography electrospray ionization orbitrap tandem mass spectrometry. ICR mice were challenged by MCAO/R surgery. The protective effect of MLST on MCAO/R injury was evaluated by neurological deficit score, cerebral infarct rate, brain water content, H&E and nissl staining. The blood-brain barrier (BBB) integrity was detected by Evans blue staining. The potential pharmacological mechanism of MLST in treating MCAO/R injury was further elucidated by the methods of proteomics, central carbon targeted metabolomics, as well as Western blot. Immunohistochemistry was used to detect the microglia infiltration, enzyme linked immunosorbent assay (ELISA) kit was explored to evaluate the content of IL-1β, TNF-α and IL-6 in brain tissue, and Western blot was used to detect proteins expression in brain tissue. A total of 76 chemical compounds have been determined in MLST. MLST effectively protected mice from MCAO/R injury, which was confirmed by lower neurological deficit score, cerebral infarct rate, brain water content and nissl body loss, and improved brain pathology. Meanwhile, MLST upregulated the expression of ZO-1, Occludin and Claudin 5 by downregulating the ratio of TIMP1/MMP9 to suppress the entrance of Evans blue to brain tissue, indicating that MLST maintained the integrity of BBB. Further studies indicated that MLST inhibited the inflammatory level of brain tissue by inhibiting microglia infiltration and downregulating NLRP3 inflammasome signaling pathway. The results of proteomics, Western blot, and central carbon targeted metabolomics confirmed that MLST regulated Glycolysis/Gluconogenesis, Pyruvate metabolism and TCA cycle in brain tissue of mice with MCAO/R. MLST inhibits neuroinflammation by regulating glucose metabolism disorders to interfere with immune metabolism reprogramming and inhibit the NLRP3 inflammasome signaling pathway, and finally improve cerebral ischemia-reperfusion injury. This study confirms that MLST is a potential drug for treating Cerebral ischemic stroke.

Guan Y ，Pan L ，Niu D ，Li X ，Li S ，Cheng G ，Zeng Z ，Yue R ，Yao J ，Zhang G ，Sun C ，Yang H ... -  《-》

[Huanglian jiedu decoction active fraction protects ipsilateral thalamus injury in MCAO rats through regulating astrocytes].

Zhao H ，Long JF ，Zou HY ，Zhang QX ，Zhang J ，Wang-Lei ，Zhang L ，Bian BL ，Zhao HY ... -  《-》

Neuroprotective effect of glycosides in Buyang Huanwu Decoction on pyroptosis following cerebral ischemia-reperfusion injury in rats.

Buyang Huanwu Decoction (BYHWD) is used in classical traditional Chinese medicine to prevent and treat cerebral ischemia. Glycosides, which are effective components extracted from BYHWD, mainly include astragaloside IV, paeoniflorin, and amygdalin. These glycosides are the primary pharmacologically effective constituents of BYHWD that act against cerebral ischemic nerve injury; however, the mechanism of action of BYHWD is still unclear. The present study aimed to determine the effect of BYHWD glycosides on pyroptosis after cerebral ischemia reperfusion injury and explore whether its mechanism involves the classical pyroptosis pathway mediated by NLRP3. Adult male Sprague-Dawley rats (n = 140) were randomly divided into seven groups: sham, cerebral ischemia and reperfusion (I/R), glycosides (0.064 g/kg, 0.128 g/kg, and 0.256 g/kg), BYHWD, and AC-YVAD-CMK (caspase-1 inhibitor). A rat model of cerebral I/R was established via classic middle cerebral artery occlusion (MCAO) for 2 h, followed by 24-h reperfusion. Neurological function was estimated using neurological defect scores. Brain infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining, and nerve cell damage was evaluated by Nissl staining. Pyroptosis was detected using TUNEL and caspase-1 immunofluorescence double staining. Protein expression of NLRP3, ASC, caspase-1, pro-caspase-1, and IL-1β was analyzed using Western blot analysis. Glycosides improved neurological dysfunction, alleviated neuronal damage, and inhibited neuronal pyroptosis. The 0.128 g/kg glycosides group showed the most significant effects. Furthermore, we observed that this group showed significant inhibition of the expression of NLRP3, ASC, pro-caspase-1, caspase-1, and IL-1β proteins of the NLRP3-mediated classical pathway of pyroptosis. Glycosides exert neuroprotective effects by inhibiting pyroptosis of neurons after cerebral I/R injury. The underlying mechanism of action is closely related to the regulation of the classical pyroptosis pathway by NLRP3.

She Y ，Shao L ，Zhang Y ，Hao Y ，Cai Y ，Cheng Z ，Deng C ，Liu X ... -  《-》