Stimulatory effect of docosahexaenoic acid alone or loaded in zinc oxide or silver nanoparticles on the expression of glucose transport pathway

Abstract

The role of glucose transporters (GLUTs) in diabetes mellitus has become more prominent as a possible therapeutic target. In the present study, we aimed to compare the effect of zinc oxide nanoparticles (ZnONPs), silver nanoparticles (AgNPs), and docosahexaenoic acid (DHA) alone or loaded in ZnONPs or AgNPs on insulin signaling pathway and GLUTs expression in diabetic rats. In the experimental part, rats were divided into seven groups; control, diabetic, and the other five groups were diabetic received different treatments. Fasting blood sugar (FBS), serum level of insulin, insulin resistance (IR), and serum level of phosphatidylinositol 3-kinase (PI3K) were evaluated. In addition, insulin expression in pancreatic islets was assessed by immunohistochemical analysis, and the expression of liver GLUTs 1, 2, and 4 and liver insulin receptor substrate-1 (IRS-1) was evaluated by real-time polymerase chain reactions (RT-PCR).

The results of the current study showed that ZnONPs, AgNPs, and DHA alone or loaded in ZnONPs or AgNPs attenuated levels of FBS, insulin and decreased IR in diabetic rats through enhancing the expression of GLUTs as well as IRS-1 and PI3K. Furthermore, AgNPs loaded with DHA showed the most significance with high comparability to the control group.

In conclusion, this study elucidated the role of GLUTs and IRS-1 in diabetes and introduced novel characteristics of ZnONPs, AgNPs, and DHA alone or loaded in ZnONPs or AgNPs as a therapeutic modality to activate GLUTs and IRS1, which may be beneficial for diabetic patients with IR.

Abbreviations GLUTsGlucose transportersZnONPsZinc oxide nanoparticlesAgNPsSilver nanoparticlesDHADocosahexaenoic acidFBSFasting blood sugarIRInsulin resistancePI3KPhosphatidylinositol 3-kinaseIRS-1Insulin receptor substrate-1Akt1Phosphoinositide-dependent kinase-1PKCProtein kinase CFAsFatty acidsLCPUFALong-chain polyunsaturated fatty acidsEPAEicosapentaenoic acidNPsNanoparticlesAgNO3Silver nitrateZn(NO3)26H2OZinc nitrateSTZStreptozotocinCNCCellulose nanocrystalNaOHSodium hydroxide