Ramulus Cinnamomi extract attenuates neuroinflammatory responses via downregulating TLR4/MyD88 signaling pathway in BV2 cells

Ramulus Cinnamomi （RC）, a traditional Chinese herb, has been used to attenuate inflammatory responses. The purpose of this study was to investigate the effect of RC extract on lipopolysaccharide （LPS）-induced neuroinflammation in BV2 microglial cells and the underlying mechanisms involved. BV2 cells were incubated with normal medium （control group）, LPS, LPS plus 30 pg/mL RC extract, or LPS plus 100 pg/mL RC extract. The BV2 cell morphology was observed under an optical microscope and cell viability was detected by MTT assay. Nitric oxide level in BV2 cells was detected using Griess regents, and the levels of interleukin-6, interleukin-1 β, and tumor necrosis factor u in BV2 cells were determined by ELISA. The expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 proteins were detected by western blot assay. Compared with the LPS group, both 30 and 100 μg/mL RC extract had no significant effect on the viability of BV2 cells. The levels of nitric oxide, interleukin-6, interleukin-1β and tumor necrosis factor ct in BV2 cells were all significantly increased after LPS induction, and the levels were significantly reversed after treatment with 30 and 100 μg/mL RC extract. Furthermore, RC extract significantly inhibited the protein expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 in LPS-induced BV2 cells. Our findings suggest that RC extract alleviates neuroinflammation by downregulating the TLR4/MyD88 signaling pathway.

The extract of Ramulus Cinnamom attenuates inflammatory injury induced by LPS via regulation of TLR4/MyD88 signaling pathway in BV2 cells

OBJECTIVE To investigate the effects of ex-tract of Ramulus Cinnamom(RC)against LPS-induced inflammation in microglia.METHODS Activated microglia releases various pro-inflammatory cytokines to induce neuroinflammation in stroke.Lipopolysaccaride(LPS)is an endotoxin from the outer membrane of Gram-negative bacteria that activates microglia.MTT assay was used to observe the cell viability.The content of NO in supernatant was measured by Griess reagent.The levels of IL-1β,IL-6 and TNF-αin supernatant were detected by ELISA kits.The intracellular COX-2,TLR4,and My D88expression was assayed by Western blotting.RESULTS RC extract 30 and 100μg·m L-1significantly decreased the production of related inflammatory factors such as NO(P<0.05,P<0.01),IL-1β(P<0.01,P<0.01),IL-6(P<0.05,P<0.01)and TNF-α(P<0.01,P<0.01).Furthermore,RC extract significantly inhibited the COX-2,TLR4,and My D88 expression induced by LPS in BV2cells.CONCLUSION RC extract may have therapeutic potential for the improvement of neuroinflammation,and the mechanism may be involved in down-regulation of TLR4/My D88 inflammation pathway.

Amyloid precursor-like protein 2 C-terminal fragments upregulate S100A9 gene and protein expression in BV2 cells

The murine microglial cell line BV2 has neuroprotective effects, but is toxic to neurons by secret-ing inlfammatory cytokines, and is an important target in the treatment of nerve inlfammation and neurodegenerative diseases. In the present study, we observed the effects of transfecting three amyloid precursor-like protein 2 （APLP2） C-terminal fragments （CTFs; C57, C50 and C31） in the pEGFP-N1 vector on S100A9 expression in BV2 cells. Reverse transcription-PCR, western blot assay and immunocytochemistry revealed that S100A9 protein and mRNA expression was greater in BV2 cells after CTF transfection than after mock transfection with an empty vector. Furthermore, transfection of full-length APLP2-751 resulted in low levels of S100A9 protein ex-pression. Our results show that APLP2-CTFs upregulate S100A9 protein and mRNA expression in BV2 cells, and identify a novel pathway involved in neuronal injury and apoptosis, and repair and protection in Alzheimer’s disease.

Exploring the mechanism of Yishen Daluo decoction in the treatment of multiple sclerosis based on network pharmacology and in vitro experiments

Objective:To explore the mechanism and related active components of Yishen Daluo decoction(YSDLD)in treating multiple sclerosis(MS).Methods:Targets of YSDLD were collected through the TCMSP,Chemistry,and TCMID databases.The MS targets were collected through OMIM,DrugBank,Gencards,TTD,and Pharmgkb databases.We built“componentetarget”network diagrams and proteineprotein interaction(PPI)diagrams and performed topological analysis.The targets were subjected to GO and KEGG enrichment analysis.Molecular docking verification was conducted on selected targets and molecules.Finally,in vitro experiments were con-ducted.BV2 cells were induced by lipopolysaccharide for model establishment.CCK8 experiment was conducted to explore the effect of YSDLD and RT-qPCR technology was used to explore the expression of key targets.Results:There were 184 active components in YSDLD and 898 targets of its action.There were 940 MS targets,and 215 targets were shared by YSDLD and MS.According to the“componentetarget”diagram,the top five key components included quercetin,kaempferol,beta-sitosterol,stigmasterol,and nar-ingenin.IL-6,IL-1 b,TNF-α,AKT1,and VEGFA were the important targets identified by PPI network to-pology analysis.A total of 564 functions were identified by GO enrichment analysis(P<0.01),mainly involving inflammatory response,hypoxia response,plasma membrane,neuronal cell body,protein phosphatase binding,and cytokine activity.KEGG enrichment analysis enriched 98 pathways(P<.01).YSDLD at the concentration of 20 m g/mL had no effect on BV2 cells.RT-qPCR indicated that YSDLD at the concentrations of 15 m g/mL and 20 m g/mL alleviated LPS-induced inflammatory injury and lowered the content of inflammatory factors(P<0.05).Conclusion:In this paper,the network pharmacology and in vitro experiments were used to explore the potential mechanism of YSDLD in treating MS.The research provides a good basis for the development of YSDLD and drugs for MS in future.