Malondialdehyde and 4-hydroxynonenal adducts are not formed on cardiac ryanodine receptor (RyR2) and sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2) in diabetes

Mol Cell Biochem. 2013 Apr;376(1-2):121-35. doi: 10.1007/s11010-013-1558-1. Epub 2013 Jan 25.

Abstract

Recently, we reported an elevated level of glucose-generated carbonyl adducts on cardiac ryanodine receptor (RyR2) and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2) in hearts of streptozotocin(STZ)-induced diabetic rats. We also showed these adduct impaired RyR2 and SERCA2 activities, and altered evoked Ca(2+) transients. What is less clear is if lipid-derived malondialdehyde (MDA) and 4-hydroxy-2-nonenal (4-HNE) also chemically react with and impair RyR2 and SERCA2 activities in diabetes? This study used western blot assays with adduct-specific antibodies and confocal microscopy to assess levels of MDA, 4-HNE, N (ε)-carboxy(methyl)lysine (CML), pentosidine, and pyrraline adducts on RyR2 and SERCA2 and evoked intracellular transient Ca(2+) kinetics in myocytes from control, diabetic, and treated-diabetic rats. MDA and 4-HNE adducts were not detected on RyR2 and SERCA2 from either control or 8 weeks diabetic rats with altered evoked Ca(2+) transients. However, CML, pentosidine, and pyrraline adducts were elevated three- to five-fold (p < 0.05). Treating diabetic rats with pyridoxamine (a scavenger of reactive carbonyl species, RCS) or aminoguanidine (a mixed reactive oxygen species-RCS scavenger) reduced CML, pentosidine, and pyrraline adducts on RyR2 and SERCA2 and blunted SR Ca(2+) cycling changes. Treating diabetic rats with the superoxide dismutase mimetic tempol had no impact on MDA and 4-HNE adducts on RyR2 and SERCA2, and on SR Ca(2+) cycling. From these data we conclude that lipid-derived MDA and 4-HNE adducts are not formed on RyR2 and SERCA2 in this model of diabetes, and are therefore unlikely to be directly contributing to the SR Ca(2+) dysregulation.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehydes / chemistry
  • Aldehydes / metabolism*
  • Animals
  • Arginine / analogs & derivatives
  • Arginine / chemistry
  • Arginine / metabolism
  • Calcium / metabolism
  • Cyclic N-Oxides / pharmacology
  • Diabetes Mellitus, Experimental / drug therapy
  • Diabetes Mellitus, Experimental / metabolism*
  • Diabetes Mellitus, Experimental / physiopathology
  • Diabetic Cardiomyopathies / metabolism
  • Echocardiography / methods
  • Guanidines / pharmacology
  • Lysine / analogs & derivatives
  • Lysine / chemistry
  • Lysine / metabolism
  • Male
  • Malondialdehyde / chemistry
  • Malondialdehyde / metabolism*
  • Myocytes, Cardiac / drug effects
  • Myocytes, Cardiac / metabolism*
  • Norleucine / analogs & derivatives
  • Norleucine / chemistry
  • Norleucine / metabolism
  • Protein Carbonylation
  • Pyridoxamine / pharmacology
  • Pyrroles / chemistry
  • Pyrroles / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Ryanodine Receptor Calcium Release Channel / chemistry
  • Ryanodine Receptor Calcium Release Channel / metabolism*
  • Sarcoplasmic Reticulum / metabolism
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases / chemistry
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases / metabolism*
  • Spin Labels

Substances

  • Aldehydes
  • Atp2a2 protein, rat
  • Cyclic N-Oxides
  • Guanidines
  • Pyrroles
  • Ryanodine Receptor Calcium Release Channel
  • Spin Labels
  • Malondialdehyde
  • Pyridoxamine
  • N(6)-carboxymethyllysine
  • 2-formyl-5-(hydroxymethyl)pyrrole-1-norleucine
  • Norleucine
  • Arginine
  • pentosidine
  • Sarcoplasmic Reticulum Calcium-Transporting ATPases
  • 4-hydroxy-2-nonenal
  • Lysine
  • pimagedine
  • Calcium
  • tempol