Conjugated linoleic acid (CLA) is a mixture of positional and geometric isomers of
linoleic acid found in beef, lamb, and dairy products. CLA has attracted considerable attention over the past several decades because of its potentially beneficial biologic effects, including protective effects against several
cancers,
atherosclerosis, and
obesity. In previous studies, we provided evidence that dietary CLA could prevent the development of
obesity-related
hypertension in obese animals. Here, we show that CLA suppresses the development of non-obese
essential hypertension in spontaneously hypertensive rats (SHRs). After 4 weeks of feeding with CLA, the increase of systolic blood pressure was significantly suppressed compared with rats fed
linoleic acid. Abdominal adipose tissue weight was also significantly lowered in CLA-fed SHRs. Content of
arachidonic acid, the substrate of
eicosanoid production, was not changed, but accumulation of
oleic acid, the lipogenesis end-product, was markedly decreased in the membrane
phospholipids of CLA-fed SHRs. In addition, we found increased level of plasma
adiponectin, suggested as a regulatory factor of
hypertension, through the enhancement of
mRNA expression in CLA-fed SHRs. We speculate that the
antihypertensive effect of dietary CLA may be due to the increase of plasma
adiponectin level and associated with the alleviation of membrane abnormality in SHRs.