Ang (1-7) protects islet endothelial cells from palmitate-induced apoptosis by AKT, eNOS, p38 MAPK, and JNK pathways

J Diabetes Res. 2014:2014:391476. doi: 10.1155/2014/391476. Epub 2014 Apr 2.

Abstract

This study aimed to explore the effect of angiotensin (1-7) (Ang (1-7)) on palmitate-induced apoptosis in islet endothelial cells and the mechanism of action. MS-1 cells were treated with palmitate in the presence or absence of Ang (1-7). The percentage of apoptotic cells was determined by DNA fragmentation and flow cytometry. Reactive oxygen species (ROS) production was measured using a Reactive Oxygen Species Assay Kit. Expression of AKT, eNOS, C-Jun N-terminal kinase (JNK), and p38 was detected by western blotting. Compared with palmitate treated group, palmitate-induced apoptosis was decreased in MS-1 cells which were preincubated with Ang (1-7) (P < 0.05). Palmitate decreased the phosphorylation of AKT and eNOS, and Ang (1-7) increased the phosphorylation of these kinases (P < 0.05), with a concomitant reduction in MS-1 cells apoptosis. Ang (1-7) also inhibited the palmitate-induced ROS production and attenuated the apoptosis-related signaling molecule JNK and p38 activation (all P < 0.05). PI3K/AKT, eNOS, p38 MAPK, and JNK inhibitors blocked the antilipoapoptosis of Ang (1-7) (all P < 0.05). Our findings suggest that Ang (1-7) reduces palmitate-induced islet endothelial cells apoptosis. AKT/eNOS/NO signaling and JNK and p38 pathway are involved in the Ang (1-7)-mediated modulation of islet endothelial cells lipoapoptosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiotensin I / antagonists & inhibitors
  • Angiotensin I / pharmacology*
  • Angiotensin II / analogs & derivatives
  • Angiotensin II / pharmacology
  • Animals
  • Antihypertensive Agents / antagonists & inhibitors
  • Antihypertensive Agents / pharmacology
  • Apoptosis / drug effects*
  • Cell Line, Transformed
  • Endothelium, Vascular / drug effects*
  • Endothelium, Vascular / enzymology
  • Endothelium, Vascular / metabolism
  • Enzyme Activation / drug effects
  • Fatty Acids, Nonesterified / antagonists & inhibitors
  • Fatty Acids, Nonesterified / metabolism
  • Islets of Langerhans / blood supply
  • Islets of Langerhans / drug effects*
  • Islets of Langerhans / metabolism
  • MAP Kinase Kinase 4 / antagonists & inhibitors
  • MAP Kinase Kinase 4 / chemistry
  • MAP Kinase Kinase 4 / metabolism
  • MAP Kinase Signaling System / drug effects*
  • Mice
  • Microvessels / drug effects
  • Microvessels / enzymology
  • Microvessels / metabolism
  • Nitric Oxide Synthase Type III / antagonists & inhibitors
  • Nitric Oxide Synthase Type III / chemistry
  • Nitric Oxide Synthase Type III / metabolism*
  • Palmitic Acid / antagonists & inhibitors
  • Palmitic Acid / metabolism
  • Peptide Fragments / antagonists & inhibitors
  • Peptide Fragments / pharmacology*
  • Protective Agents / chemistry
  • Protective Agents / pharmacology
  • Protein Kinase Inhibitors / pharmacology
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins / agonists
  • Proto-Oncogene Proteins / antagonists & inhibitors
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins c-akt / agonists*
  • Proto-Oncogene Proteins c-akt / antagonists & inhibitors
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, G-Protein-Coupled / agonists
  • Receptors, G-Protein-Coupled / antagonists & inhibitors
  • Receptors, G-Protein-Coupled / metabolism
  • Signal Transduction / drug effects
  • p38 Mitogen-Activated Protein Kinases / antagonists & inhibitors
  • p38 Mitogen-Activated Protein Kinases / chemistry
  • p38 Mitogen-Activated Protein Kinases / metabolism

Substances

  • 7-Ala-angiotensin (1-7)
  • Antihypertensive Agents
  • Fatty Acids, Nonesterified
  • Peptide Fragments
  • Protective Agents
  • Protein Kinase Inhibitors
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins
  • Receptors, G-Protein-Coupled
  • Angiotensin II
  • Palmitic Acid
  • Angiotensin I
  • Nitric Oxide Synthase Type III
  • Nos3 protein, mouse
  • Akt1 protein, mouse
  • Proto-Oncogene Proteins c-akt
  • p38 Mitogen-Activated Protein Kinases
  • MAP Kinase Kinase 4
  • Map2k4 protein, mouse
  • angiotensin I (1-7)