Objective To investigate the effect and mechanism of linarin(LA) in an experimental dry eye model.Methods LA or vehicle was applied in two dry eye models: an in vitro hyperosmotic stress model and an in vivo desiccati...Objective To investigate the effect and mechanism of linarin(LA) in an experimental dry eye model.Methods LA or vehicle was applied in two dry eye models: an in vitro hyperosmotic stress model and an in vivo desiccating stress(DS) murine model. The viability of human corneal epithelial cells(HCECs) was measured using a cell counting kit(CCK-8).Tear secretion was assessed using the phenol red cotton test. The tear break-up time(TBUT) was recorded using 0.1% liquid fluorescein sodium. Corneal epithelial permeability was evaluated through Oregon green dextran(OGD) staining.Conjunctival goblet cells were counted using periodic acid-Schiff(PAS) staining. Terminal deoxynucleotidyl transfer d UTP nickend labeling(TUNEL) staining was used to quantify apoptotic cells in both models. The expression of Ki-67 was measured in HCECs in the cell model while that of matrix metalloproteinase(MMP)-3 and-9 was measured in the murine model through immunofluorescence staining. Real-time quantitative PCR(RTqPCR) was performed to assess the expression of MMP-3 and MMP-9 in the corneal epithelium and NLRP3, ASC, Caspase-1,interleukin(IL)-1β, IL-18, and tumor necrosis factor(TNF)-α in the conjunctiva. The protein expression levels of NLRP3, ASC,Caspase-1, IL-1β, and IL-18 in the conjunctiva were assessed via Western blot.Results In the in vitro model, treatment of HCECs with LA showed no toxicity, increased proliferation, and reduced apoptosis. In the murine model, compared to the control, LA significantly increased tear production and TBUT, improved OGD staining, and increased the number of goblet cells. Topical treatment of LA to mice provided decreased expression of MMP-3, MMP-9, TNF-α, and apoptotic corneal epithelium. Topical administration of LA also suppressed the NLRP3 inflammasome in the dry eye disease(DED) murine model by decreasing the expression of NLRP3, ASC, Caspase-1, IL-1β, and IL-18 in the conjunctiva.Conclusion Our findings support the safety and efficacy of LA in the treatment of DED. LA alleviated corneal epithelial damage and suppressed NLRP3 inflammasome-mediated immunity in the conjunctiva in a murine model of DED.展开更多
The study aims to investigate the effects of(-)-Linarinic acid(LA) and one of its derivatives(LAd) on brain injury induced by ischemia. Malonaldehyde(MDA) is determined as an index for lipid peroxidation both in vitro...The study aims to investigate the effects of(-)-Linarinic acid(LA) and one of its derivatives(LAd) on brain injury induced by ischemia. Malonaldehyde(MDA) is determined as an index for lipid peroxidation both in vitro and vivo. Mice were pre-treated with LA and LAd for 3 d.Thereafter, they were induced to have incomplete cerebral ischemia with both bilateral carotid artery occlusion and hypotension(BCAOH). In the first part of the in vivo experiment, mice were divided into four groups: sham(control), ischemia, ischemia + LA(200 mg/kg, i.g.) and ischemia + LAd(200 mg/kg, i.g.). In the second part, the dose-response of LAd was investigated at 100, 200 and 400 mg/kg i.g., respectively. A modified neurological severity score was developed for evaluating behavioral deficits of the mice with ischemia. Brains of the mice were excised in order to determinate MDA after ischemia for 6 h. Survival time, survival rate, neurological injury score and MDA level in brains were observed. Results were: 1) The data in vitro showed that both LA and LAd could inhibit the generation of MDA. IC50 values obtained by Probit analysis were 2.9 mM for LAd and 4.88 mM for LA;2) BCAOH could significantly shorten the survival span, reduce the survival rate and cause neurological deficits,which were associated with high level of lipid hydroperoxide production in cerebral tissues;3) LAd decreased lipid peroxidation and improved the neurological outcome more than LA.It is concluded that LAd offers a better neuroprotection than LA against brain damage caused by cerebral ischemia.展开更多
Objective:The purpose of this study is to investigate the anti-diabetic effects of linarin,a flavonoid extracted from Chrysanthemi Indici Flos(CIF),and its potential mechanisms.Methods:The effects of linarin on cell v...Objective:The purpose of this study is to investigate the anti-diabetic effects of linarin,a flavonoid extracted from Chrysanthemi Indici Flos(CIF),and its potential mechanisms.Methods:The effects of linarin on cell viability and glucose consumption in Hep G2 cells were measured.Meanwhile,monosodium glutamate(MSG) mouse model was constructed to monitor the changes of insulin tolerance,glucose tolerance,triglyceride and cholesterol.The protein expression levels of pAMPK,p-ACC,PEPCK and p-GS were detected by Western blot.Results:Linarin could increase the relative glucose consumption of Hep G2 cells,improve insulin tolerance and glucose tolerance,and decrease the levels of triglyceride and cholesterol of MSG mice.Simultaneously,the expression levels of p-AMPK and p-ACC in Hep G2 cells and the liver tissue of MSG mice were increased,while the expression levels of PEPCK and p-GS were decreased after treatment with linarin.Conclusion:Insulin resistance could be ameliorated by linarin in type 2 diabetes,and its mechanism may be related to AMPK signaling pathway.展开更多
Objective:The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin.Methods:L...Objective:The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin.Methods:Linarin solid dispersion(LSD)and linarin liposome(LL)were developed via the solvent method and the thin film hydration method respectively.The Transwell chamber model of Caco-2 cells was established to evaluate the absorption of drug.The pharmacokinetics of linarin,LSD and LL in rats after ig administration were carried out by high performance liquid chromatography(HPLC)method.Results:The solubility of LSD and LL was severally 3.29 times and 3.09 times than that of linarin.The permeation coefficients of LSD and LL were greater than 10^(-6),indicating that the absorption of LSD and LL were both better than linarin.The bioavailability of the LSD was 3.363 times higher than that of linarin,and the bioavailability of LL was 0.9886 times higher than that of linarin.Conclusion:The linarin was more suitable for making solid dispersion to enhance its solubility and bioavailability.展开更多
基金funding support from the China Postdoctoral Science Foundation Grant (No. 2018M632973)Sichuan Science and Technology Program (No. 2018JY0388)+3 种基金the First-Class Open Fund for Integrated Chinese and Western Medicine (No. 2018ZXYJH05)Traditional Chinese Medicine First-Class Discipline Open Fund (No. 2018ZYX57)the Construction Project of the Hunan Engineering Technology Research Center for the Prevention and Treatment of Otorhinolaryngologic Diseases and Protection of Visual Function with Chinese Medicine (No. 2018YGC02 and No. 2018YGC04)the Research and Innovation Project of Graduate Students in Hunan Province (No. CX20190538)
文摘Objective To investigate the effect and mechanism of linarin(LA) in an experimental dry eye model.Methods LA or vehicle was applied in two dry eye models: an in vitro hyperosmotic stress model and an in vivo desiccating stress(DS) murine model. The viability of human corneal epithelial cells(HCECs) was measured using a cell counting kit(CCK-8).Tear secretion was assessed using the phenol red cotton test. The tear break-up time(TBUT) was recorded using 0.1% liquid fluorescein sodium. Corneal epithelial permeability was evaluated through Oregon green dextran(OGD) staining.Conjunctival goblet cells were counted using periodic acid-Schiff(PAS) staining. Terminal deoxynucleotidyl transfer d UTP nickend labeling(TUNEL) staining was used to quantify apoptotic cells in both models. The expression of Ki-67 was measured in HCECs in the cell model while that of matrix metalloproteinase(MMP)-3 and-9 was measured in the murine model through immunofluorescence staining. Real-time quantitative PCR(RTqPCR) was performed to assess the expression of MMP-3 and MMP-9 in the corneal epithelium and NLRP3, ASC, Caspase-1,interleukin(IL)-1β, IL-18, and tumor necrosis factor(TNF)-α in the conjunctiva. The protein expression levels of NLRP3, ASC,Caspase-1, IL-1β, and IL-18 in the conjunctiva were assessed via Western blot.Results In the in vitro model, treatment of HCECs with LA showed no toxicity, increased proliferation, and reduced apoptosis. In the murine model, compared to the control, LA significantly increased tear production and TBUT, improved OGD staining, and increased the number of goblet cells. Topical treatment of LA to mice provided decreased expression of MMP-3, MMP-9, TNF-α, and apoptotic corneal epithelium. Topical administration of LA also suppressed the NLRP3 inflammasome in the dry eye disease(DED) murine model by decreasing the expression of NLRP3, ASC, Caspase-1, IL-1β, and IL-18 in the conjunctiva.Conclusion Our findings support the safety and efficacy of LA in the treatment of DED. LA alleviated corneal epithelial damage and suppressed NLRP3 inflammasome-mediated immunity in the conjunctiva in a murine model of DED.
基金supported partly by a grant from Natural Science Foundation of China (30973613)
文摘The study aims to investigate the effects of(-)-Linarinic acid(LA) and one of its derivatives(LAd) on brain injury induced by ischemia. Malonaldehyde(MDA) is determined as an index for lipid peroxidation both in vitro and vivo. Mice were pre-treated with LA and LAd for 3 d.Thereafter, they were induced to have incomplete cerebral ischemia with both bilateral carotid artery occlusion and hypotension(BCAOH). In the first part of the in vivo experiment, mice were divided into four groups: sham(control), ischemia, ischemia + LA(200 mg/kg, i.g.) and ischemia + LAd(200 mg/kg, i.g.). In the second part, the dose-response of LAd was investigated at 100, 200 and 400 mg/kg i.g., respectively. A modified neurological severity score was developed for evaluating behavioral deficits of the mice with ischemia. Brains of the mice were excised in order to determinate MDA after ischemia for 6 h. Survival time, survival rate, neurological injury score and MDA level in brains were observed. Results were: 1) The data in vitro showed that both LA and LAd could inhibit the generation of MDA. IC50 values obtained by Probit analysis were 2.9 mM for LAd and 4.88 mM for LA;2) BCAOH could significantly shorten the survival span, reduce the survival rate and cause neurological deficits,which were associated with high level of lipid hydroperoxide production in cerebral tissues;3) LAd decreased lipid peroxidation and improved the neurological outcome more than LA.It is concluded that LAd offers a better neuroprotection than LA against brain damage caused by cerebral ischemia.
基金supported by the National Natural Science Foundation of China (grant numbers 81273392)the Natural Science Foundation of Henan Province (grant numbers 182300410348)
文摘Objective:The purpose of this study is to investigate the anti-diabetic effects of linarin,a flavonoid extracted from Chrysanthemi Indici Flos(CIF),and its potential mechanisms.Methods:The effects of linarin on cell viability and glucose consumption in Hep G2 cells were measured.Meanwhile,monosodium glutamate(MSG) mouse model was constructed to monitor the changes of insulin tolerance,glucose tolerance,triglyceride and cholesterol.The protein expression levels of pAMPK,p-ACC,PEPCK and p-GS were detected by Western blot.Results:Linarin could increase the relative glucose consumption of Hep G2 cells,improve insulin tolerance and glucose tolerance,and decrease the levels of triglyceride and cholesterol of MSG mice.Simultaneously,the expression levels of p-AMPK and p-ACC in Hep G2 cells and the liver tissue of MSG mice were increased,while the expression levels of PEPCK and p-GS were decreased after treatment with linarin.Conclusion:Insulin resistance could be ameliorated by linarin in type 2 diabetes,and its mechanism may be related to AMPK signaling pathway.
基金financed by Natural Science Foundation of Henan Province(Grant No.182300410348)。
文摘Objective:The current investigation aimed to determine the appropriate dosage form by comparing solid dispersion and liposome to achieve the purpose of improving the solubility and bioavailability of linarin.Methods:Linarin solid dispersion(LSD)and linarin liposome(LL)were developed via the solvent method and the thin film hydration method respectively.The Transwell chamber model of Caco-2 cells was established to evaluate the absorption of drug.The pharmacokinetics of linarin,LSD and LL in rats after ig administration were carried out by high performance liquid chromatography(HPLC)method.Results:The solubility of LSD and LL was severally 3.29 times and 3.09 times than that of linarin.The permeation coefficients of LSD and LL were greater than 10^(-6),indicating that the absorption of LSD and LL were both better than linarin.The bioavailability of the LSD was 3.363 times higher than that of linarin,and the bioavailability of LL was 0.9886 times higher than that of linarin.Conclusion:The linarin was more suitable for making solid dispersion to enhance its solubility and bioavailability.
