To evaluate the participation of mitochondrial damage, oxygen radicals and cell death in diabetes mellitus, we designed a way to investigate INS-1 cells, rat pancreatic beta-cell line, to die by treatment with alloxan which generate reactive oxygen species (ROS). Incubation of INS-1 cells with alloxan for 24 h resulted in a decrease in viability of cells as well as inhibition of glucose-stimula...

Elevated extracellular free fatty acids (FFAs) can induce pancreatic beta cell apoptosis, thereby contributing to the pathogenesis of type 2 diabetes mellitus (T2D). Mitochondrial dysfunction has been implicated in FFA-induced beta cell apoptosis. However, molecular mechanisms linking mitochondrial dysfunction and FFA-induced beta cell apoptosis are not clear. Dynamin-related protein 1 (DRP-1) ...

We characterized the effect of phytic acid (inositol hexaphosphate, IP6) as a potential adjuvant in treatment of colorectal carcinoma and evaluated the optimal concentration and treatment time to produe the maximal therapeutic effect. There is some evidence that myoinositol (Ins) can potentiate anti-cancer effects of IP6. Therefore, we tested both IP6 and Ins individually and in combination on ...

p130 was originally identified as an Ins(1,4,5)P(3)-binding protein similar to phospholipase C-delta but lacking any phospholipase activity. In the present study we have further analysed the interactions of p130 with inositol compounds in vitro. To determine which of the potential ligands interacts with p130 in cells, we performed an analysis of the cellular localization of this protein, the is...

Chronic exposure to elevated saturated free fatty acid (FFA) levels has been shown to induce endoplasmic reticulum (ER) stress that may contribute to promoting pancreatic beta-cell apoptosis. Here, we compared the effects of FFAs on apoptosis and ER stress in human islets and two pancreatic beta-cell lines, rat INS-1 and mouse MIN6 cells. Isolated human islets cultured in vitro underwent apopto...

Altered secretion of insulin as well as glucagon has been implicated in the pathogenesis of Type 2 diabetes (T2D), but the mechanisms controlling glucagon secretion from α-cells largely remain unresolved. Therefore, we studied the regulation of glucagon secretion from αTC1-6 (αTC1 clone 6) cells and compared it with insulin release from INS-1 832/13 cells. We found that INS-1 832/13 and αTC1-6 ...

Membrane capacitance and membrane conductance values are reported for insulin secreting cells (primary -cells and INS-1 insulinoma cells), determined using the methods of dielectrophoresis and electrorotation. The membrane capacitance value of 12.57 (+/-1.46) mFm(-2), obtained for -cells, and the values from 9.96 (+/-1.89) mFm(-2) to 10.65 (+/-2.1) mFm(-2), obtained for INS-1 cells, fall within...

To investigate the therapeutic efficacy and mechanism of β-cells with insulin receptor (IR) overexpression on diabetes mellitus (DM), rat insulinoma (INS-1) cells were engineered to stably express human insulin receptor (INS-IR cells), and subsequently transplanted into streptozotocin- induced diabetic rats. Compared with INS-1 cells, INS-IR cells showed improved β-cell function, including the ...

The small ion lithium, a very effective agent in the treatment of manic depressive patients, inhibits the mammalian enzyme inositol monophosphatase, which is proposed as the biological target for the effects of lithium. In this study we investigated Dictyostelium discoideum inositol monophosphatase activity. Partial purification of the proteins in the soluble cell fraction using anion-exchange ...

The production and metabolism of inositol phosphates in rat adrenal glomerulosa cells prelabeled with [3H]inositol and stimulated with angiotensin II were analyzed by high-performance anion-exchange chromatography. Exposure to angiotensin II was accompanied by a rapid and substantial decrease in the phospholipid precursor, phosphatidylinositol (PtdIns) 4,5-bisphosphate with only a slight and tr...