Experimental study on the effect of nobiletin in the treatment of dry eyes in mice with type 2 diabetes mellitus by activating cystic fibrosis transmem-brane conductance regulators
Objective To investigate the potential value of nobiletin(NOB)in the treatment of dry eyes in type 2 di-abetes mellitus(T2DM-DE)and its effect on the expression of cystic fibrosis transmembrane conductance regulators(CFTRs).Methods The T2DM mouse model was established by a high-fat diet combined with streptozotocin,and then the T2DM-DE mouse model was induced by benzalkonium chloride.These mice were divided into 6 groups:the NC group,the T2DM-DE group,the L-NOB group,the M-NOB group,the H-NOB group,and the CFTR inhibitor group.Mice in the NC and T2DM-DE groups were provided with phosphate buffer saline(PBS)containing 0.5％Tween80 through oral ga-vage;those in the L-NOB,M-NOB,and H-NOB groups were provided with 50,100,and 200 mg•kg-1•d-1 NOB solu-tions,respectively,through oral gavage;those in the CFTR inhibitor group were provided with 200 mg•kg-1•d-1 NOB solution through oral gavage and intraperitoneally injected with 1 mg•kg-1•d-1 CFTR(inh)-172.The intervention in these groups was provided for 4 weeks.The fasting blood glucose(FPG),tear secretion,tear film break-up time(BUT),corne-al fluorescein sodium staining grade,and interleukin-1 β(IL-1 β),IL-6,IL-8,and tumor necrosis factor-α(TNF-α)levels in tears of mice were detected.Besides,the periodic acid-Schiff(PAS)staining of conjunctival goblet cells and the terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)staining of the cornea were performed respectively.The mRNA and protein expression levels of CFTRs,Bax,and Bcl-2 in the cornea were measured by the real-time quantitative polymerase chain reaction(RT-qPCR)and Western blot.Results Compared with the NC group,the FPG of mice in the T2DM-DE group increased;the level of IL-1β,IL-6,IL-8,and TNF-α in tears increased;the corneal fluorescein sodium staining grade and TUNEL positive rate increased(all P＜0.05);the tear secretion,BUT,and the number of conjunctival goblet cells decreased;the mRNA and protein expression levels of CFTRs decreased(all P＜0.05).Compared with the T2DM-DE group,the FPG of mice in the L-NOB,M-NOB,and H-NOB groups decreased;the levels of IL-1β,IL-6,IL-8,and TNF-α in tears decreased;the corneal fluorescein sodium staining grade and TUNEL positive rate decreased(all P＜0.05),the tear secretion,BUT,and the number of conjunctival goblet cells increased;the mRNA and protein expression levels of CFTRs increased(all P＜0.05).Compared with the H-NOB group,the FPG of mice in the CFTR inhibitor group increased;the levels of IL-1 β,IL-6,IL-8,and TNF-α in tear increased;the corneal fluorescein sodium staining grade and TUNEL positive rate increased(all P＜0.05);the tear secretion,BUT,and the number of conjunctival goblet cells de-creased;the mRNA and protein expression levels of CFTRs decreased(all P＜0.05).Conclusion NOB can reduce the blood glucose level by activating CFTRs,inhibit inflammation,and promote the survival of conjunctival goblet cells and cor-neal cells in T2DM-DE mice,thus playing a role in the treatment of T2DM-DE.
万方数据
维普
