Evidence of altered biochemical composition in the hearts of adult intrauterine growth-restricted rats.
OBJECTIVE
Epidemiological studies clearly link intrauterine growth restriction with increased risk of cardiac disease in adulthood. The mechanisms leading to this increased risk are poorly understood; remodeling of the myocardium is implicated. The aim was to determine the effect of early life growth restriction on the biochemical composition of the left ventricular myocardium in adult rats.


METHODS
Wistar Kyoto dams were fed either a low protein diet (LPD; 8.7 % casein) or normal protein diet (NPD; 20 % casein) during pregnancy and lactation; from weaning, the offspring were fed normal rat chow. At 18 weeks of age, the biochemical composition of the hearts of NPD control (n = 9) and LPD intrauterine growth-restricted (n = 7) offspring was analyzed using Fourier Transform Infrared (FTIR) micro-spectroscopy.


RESULTS
Body weights at postnatal day 4 were significantly lower and remained lower throughout the experimental period in the LPD offspring compared to controls. FTIR analysis of the infrared absorption spectra across the whole "fingerprint" region (1,800-950 cm(-1)) demonstrated wider variation in absorbance intensity in the LPD group compared to controls. In particular, there were marked differences detected in the protein (1,540 cm(-1)), lipid (1,455 and 1,388 cm(-1)), proteoglycan (1,228 cm(-1)) and carbohydrate (1,038 cm(-1)) bands, indicating increased lipid, proteoglycan and carbohydrate content in the growth-restricted myocardium.


CONCLUSIONS
In conclusion, changes in the biochemical composition of the myocardium provide a likely mechanism for the increased vulnerability to cardiovascular disease in offspring that were growth restricted in early life.
Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia.
Vladislava
V
Zohdi
Bayden R
BR
Wood
James T
JT
Pearson
Keith R
KR
Bambery
M Jane
MJ
Black
D000818:Animals; D001835:Body Weight; D018753:Diet, Protein-Restricted / Q000009:adverse effects; D005260:Female; D005317:Fetal Growth Retardation / Q000503:physiopathology*; D006331:Heart Diseases / Q000503:physiopathology; D006352:Heart Ventricles / Q000737:chemistry* / Q000503:physiopathology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000503:physiopathology*; D051381:Rats; D011921:Rats, Inbred WKY; D017550:Spectroscopy, Fourier Transform Infrared; D014886:Weaning