Rice Husk Silica Liquid Protects Pancreatic β Cells from Streptozotocin-Induced Oxidative Damage

Abstract

Type 2 diabetes mellitus is a complex multifactorial disease characterized by insulin resistance and dysfunction of pancreatic β-cells. Rice husk silica liquid (RHSL) is derived from rice husks and has not been explored in diabetes mellitus until now. Previous studies showed that rice husk is enriched with silica, and its silica nanoparticles are higher more biocompatible. To investigate the potential protective role of RHSL on pancreatic β cells, we utilized RIN-m5F pancreatic β cells and explored RHSL effect after streptozotocin (STZ)-stimulation. The recovery effects of RHSL were evaluated using flow cytometry, Western blotting, and immunofluorescence analysis. Results of our study showed that RHSL reversed the cell viability, insulin secretion, reactive oxygen species (ROS) production, and the change of mitochondria membrane potential (ΔΨm) in STZ-treated RIN-m5F cells. Moreover, the expression of phospho-receptor-interacting protein 3 (p-RIP3) and cleaved-poly (ADP-ribose) polymerase (PARP), phospho-mammalian target of rapamycin (p-mTOR), and sequestosome-1 (p62/SQSTM1) were significantly decreased, while the transition of light chain (LC)3-I to LC3-II was markedly increased after RHSL treatment in STZ-induced RIN-m5F cells. Interestingly, using autophagy inhibitors such as 3-methyladenine (3-MA) and chloroquine (CQ) both showed an increase in cleaved-PARP protein level, indicating apoptosis induction. Taken together, this study demonstrated that RHSL induced autophagy and alleviated STZ-induced ROS-mediated apoptosis in RIN-m5F cells.

Antioxidant Effect of Tyr-Ala Extracted from Zein on INS-1 Cells and Type 2 Diabetes High-Fat-Diet-Induced Mice

“…Excessive ROS can cause a decrease in the activity of INS-1 cells, ultimately leading to cell necrosis and apoptosis [ 28 , 29 ]. Insulin resistance is also related to oxidative-stress-induced dysfunction in type 2 diabetes [ 5 ]. In this experiment, we treated INS-1 cells with hydrogen peroxide, hA or high concentration of glucose to change ROS levels and establish an insulin resistance model.…”

“…As many factors cause T2DM, its pathogenesis remains unclear [ 4 ]. Insulin resistance (IR) and islet β-cell failure are the key pathogenic factors of T2DM [ 5 ].…”

Effects of Rice-Husk Silica Liquid in Streptozotocin-Induced Diabetic Mice

“…The regulation of blood glucose depends on the release of insulin. In our previous study, we showed that RHSL abrogated the effect of streptozotocin (STZ) on the mass of RIN-m5F pancreatic β-cells and their ability to secrete insulin [ 16 ]. In the present study, we observed similar results, where RHSL restored blood insulin concentrations, meaning that RHSL has the potential to reverse the STZ-induced insulin resistance in C57BL/J6 mice.…”

“…The detailed process of rice husk preparation can be found in previous studies [ 18 ]. In addition, the production process and the conditions of aqueous RHSL (rice-husk silica liquid) were performed according to our previous research [ 16 ]. The produced standard solution was used at the original concentration and diluted with double-distilled water (ddH 2 O) to obtain an effective dose, which was used in the subsequent experiments.…”

“…Si has been previously reported to exhibit antidiabetic effects via improving insulin resistance and lowering blood glucose levels, thereby reducing the risk of glomerulopathy [ 14 , 15 ]. Our previous study revealed the potential antidiabetic effect of rice-husk silica liquid (RHSL) on pancreatic β-cells by inducing autophagy and attenuating STZ-induced ROS-mediated apoptosis [ 16 ]. Although previous studies have shown that rice husks are rich in silica, and that nanosized silica is more biocompatible [ 17 ], the information on rice-husk silica (RHS) in food inspection and functional analysis is still limited.…”