Protective Effects of an Oxovanadium(IV) Complex with N2O2 Chelating Thiosemicarbazone on Small Intestine Injury of STZ-Diabetic Rats.

Vanadium compounds are being investigated as potential therapeutic agents in the treatment of many health problems, primarily diabetes. We aimed to provide the effect of N(1)-4-hydroxysalicylidene-N(4)-salicylidene-S-methyl-isothiosemicarbazidato-oxovanadium(IV) (VOL) on small intestinal injury in experimental male diabetic rats. Four groups were created of 3.0-3.5-month-old rats. The rats were made diabetic by a single dose of streptozotocin (STZ) at 65 mg/kg and grouped as follows: control animals, VOL-given control animals, STZ-induced diabetic animals and STZ-induced diabetic animals given VOL. A daily dose of 0.2 mM/kg vanadium complex was administered orally for 12 days after the inducement of diabetes. On the 12th day, small intestine tissue samples were taken. According to the data obtained from the biochemical analysis, reduced glutathione (GSH) level, catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), superoxide dismutase (SOD), Na+/K+-ATPase and paraoxanase (PON) activities were increased, whereas sialic acid (SA), xanthine oxidase (XO) and disaccharidases (maltase and saccharidase) activities were decreased in the small intestine tissue of VOL-treated diabetic rats. Microscopic examinations revealed a remarkable decrease in the mucosal necrotic areas, discontinuity in the brush border, deterioration of the villi integrity and oedema inside the villi, but with a mild decrease in the inflammatory cells, deterioration and loss of integrity of the gland in the small intestine of VOL-treated diabetic rats. Moreover, VOL treatment markedly decreased the proliferation of villus cells and especially inflammatory cells in the small intestine of diabetic rats. According to the obtained data, the administration of VOL is a potentially convenient strategy to reducing small intestine injury in diabetic rats.

4-Methylcatechol prevents streptozotocin-induced acute kidney injury through modulating NGF/TrkA and ROS-related Akt/GSK3ß/ß-catenin pathways.

Nerve growth factor (NGF) has been shown to protect the viability of kidney cells in acute phase of renal damage. However, since the half-life of NGF is very short, it is too large to pass the blood-brain barrier and rapidly transported to the liver for catabolizing its use in therapy is limited. 4-Methylcatechol (4MC) is a substance that increases NGF synthesis in many tissues. This study aimed to investigate the protective effects of 4MC against acute renal injury induced by streptozotocin (STZ). We have investigated the profibrotic, proinflammatory, oxidative changes in STZ-induced acute renal damage and the possible role of the NGF/TrkA system and Akt/GSK3ß/ß-catenin pathway in this mechanism. Experiment was designed as to be started with injection of 4MC for 10 days as a single dose (10 µg/kg) per day and to be terminated after 4 h of a single dose (75 mg/kg) STZ injection. As the result, 4MC pre-treatment decreased kidney damage, ROS production, the renal levels of TGFß1, CD68, tumor necrosis factor-α and interleukin 1ß. Moreover, 4MC pre-treatment increased levels of NGF and its receptor TrkA, p-Akt (Thr308), p-GSK3ß (Ser9) and nuclear ß-catenin. These data suggest that 4MC prevents the development of STZ-induced renal damage by suppressing ROS production and inflammation via Akt/GSK3ß/ß-catenin pathway which may be stimulated by NGF/TrkA signaling. Therefore, 4MC can be suggested as a potential agent for the prevention of acute renal injury.

The Role of Epigenetic Regulation and Pluripotency-Related MicroRNAs in Differentiation of Pancreatic Stem Cells to Beta Cells.

In this study, we aimed to research the effects of class-I HDACs and glucose on differentiation of pancreatic islet derived mesenchymal stem cells (PI-MSCs) to beta cells. Beta cell differentiation determined by flow cytometric analysis and gene expression levels of PDX1, PAX4, PAX6, NKX6.1, NGN3, INS2, and GLUT2. As a result the valproic acid, is an inhibitor of class-I HDACs, caused the highest beta cell differentiation in PI-MSCs. However, the cells in this group were at early stages of differentiation. Glucose co-administration to this group carried the differentiation to higher levels, but these newly formed beta cells were not functional. Moreover, reduction in the levels of pluripotency factors that Oct3/4, c-Myc, and Nanog were parallel to beta cell differentiation. Also, the levels of HDAC1 and acetylated H3/H4 were increased and methylated H3 was decreased by VPA treatment. In addition, we have detected over expression in genes of miR-18a-5p, miR-19b-5p, miR-30d-3p, miR-124, miR-146a-5p, miR-184, miR-335, and miR-433-5p in parallel to beta cell differentiation. As the conclusion, this study is important for understanding the epigenetic mechanism that controls the beta cell differentation and it suggests new molecules that can be used for diagnosis, and treatment of diabetes. J. Cell. Biochem. 119: 455-467, 2018. © 2017 Wiley Periodicals, Inc.