Abstract

Peroxisomal proliferator-activated receptors (PPAR) are a FA-response system involved in diverse cellular responses. FA regulate PPAR activity and modulate PPAR mRNA abundance. Increasing evidence indicates that PUFA are required for optimal neuronal development and function. To gain insight into the mechanism for nutrition-induced impairment of neuronal development and function we investigated the effect of chronic n-3 FA deficiency on PPAR mRNA levels in rat brain and ocular tissues. Rats were fed for three generations a diet designed to reduce DHA levels in tissues, and the abundance of PPAR? and PPAR? transcripts was measured by hybridization with specific probes. Chronic consumption of the ?-linolenic acid (LNA)-insufficient diet caused a remarkable modification in DHA content in membrane phospholipids. The results reported here indicate that PPAR? mRNA levels did not exhibit significant variation in ocular, hepatic, or nervous tissues from rats fed the experimental diet. In contrast, PPAR? mRNA normalized to ?-actin mRNA was 21% higher in ocular tissue from F3 generation rats consuming the LNA-deficient diet but was independent of diet in hepatic and nervous tissues. The absolute abundance of PPAR? transcripts showed a 17% increase in ocular tissue from rats consuming the LNA-deficient diet (F3 generation). The biological significance of the reported changes in PPAR? mRNA in ocular tissue remains to be determined.