Objective:To determine the neuroprotective effects of apigenin against streptozotocin(STZ)-induced diabetic neuropathy(DN).Methods:To induce DN,Wistar rats(150-200 g)were administered with STZ(55 mg/kg,i.p.).Then they...Objective:To determine the neuroprotective effects of apigenin against streptozotocin(STZ)-induced diabetic neuropathy(DN).Methods:To induce DN,Wistar rats(150-200 g)were administered with STZ(55 mg/kg,i.p.).Then they were randomly assigned to various groups,viz.,normal,diabetic control,insulin(10 IU/kg,s.c.),apigenin(5,10,and 20 mg/kg,p.o.),and insulin(10 IU/kg)plus apigenin(20 mg/kg,p.o.).Various behavioral,biochemical,and molecular markers[tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β,IL-6,Toll-like receptor 4(TLR4),myeloid differentiation primary response 88(MyD88),and nuclear factor erythroid 2-related factor 2(Nrf2)]were assessed.Results:Apigenin(10 and 20 mg/kg,p.o.)substantially reduced plasma glucose levels,lipid profile,aspartate transaminase,alanine transaminase,glycated hemoglobin,and neural advanced glycation end products in STZ-induced DN rats(P<0.05).After apigenin intervention,STZ-induced changes in food and water intake,body weight,urine output,allodynia,hyperalgesia,and insulin levels were markedly improved(P<0.05).Neural antioxidant enzymes(superoxide dismutase and glutathione)and Na+K+ATPase activity were also considerably elevated(P<0.05)while the level of lipid peroxidation was diminished following apigenin therapy(P<0.05).Furthermore,apigenin markedly upregulated the Nrf2 mRNA level while downregulating the mRNA expressions of TNF-αand ILs and the protein expressions of TLR4 and MyD88(P<0.05).STZ-induced histological abnormalities in the sciatic nerve were also improved by apigenin treatment.Conclusions:Apigenin exerts its neuroprotective effect by modulating the inflammatory and oxidative stress pathways via regulating the TLR4-MyD88 signaling pathway.展开更多
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 neur...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.展开更多
文摘Objective:To determine the neuroprotective effects of apigenin against streptozotocin(STZ)-induced diabetic neuropathy(DN).Methods:To induce DN,Wistar rats(150-200 g)were administered with STZ(55 mg/kg,i.p.).Then they were randomly assigned to various groups,viz.,normal,diabetic control,insulin(10 IU/kg,s.c.),apigenin(5,10,and 20 mg/kg,p.o.),and insulin(10 IU/kg)plus apigenin(20 mg/kg,p.o.).Various behavioral,biochemical,and molecular markers[tumor necrosis factor-alpha(TNF-α),interleukin(IL)-1β,IL-6,Toll-like receptor 4(TLR4),myeloid differentiation primary response 88(MyD88),and nuclear factor erythroid 2-related factor 2(Nrf2)]were assessed.Results:Apigenin(10 and 20 mg/kg,p.o.)substantially reduced plasma glucose levels,lipid profile,aspartate transaminase,alanine transaminase,glycated hemoglobin,and neural advanced glycation end products in STZ-induced DN rats(P<0.05).After apigenin intervention,STZ-induced changes in food and water intake,body weight,urine output,allodynia,hyperalgesia,and insulin levels were markedly improved(P<0.05).Neural antioxidant enzymes(superoxide dismutase and glutathione)and Na+K+ATPase activity were also considerably elevated(P<0.05)while the level of lipid peroxidation was diminished following apigenin therapy(P<0.05).Furthermore,apigenin markedly upregulated the Nrf2 mRNA level while downregulating the mRNA expressions of TNF-αand ILs and the protein expressions of TLR4 and MyD88(P<0.05).STZ-induced histological abnormalities in the sciatic nerve were also improved by apigenin treatment.Conclusions:Apigenin exerts its neuroprotective effect by modulating the inflammatory and oxidative stress pathways via regulating the TLR4-MyD88 signaling pathway.
基金supported by a grant from the National Natural Science Foundation of China,No.81473383a grant from the Medical and Health Innovation Project of Chinese Academy of Medical Sciences,No.2016-I2M-3-007a grant from Key Project of New-Drugs Creation of Science and Technology of China,No.2012ZX09103101-078 and 2017ZX09101003-003-019
文摘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.
