ABSTRACT
Bietti crystalline corneoretinal dystrophy (BCD) is an autosomal recessive retinal degenerative disease characterized by crystalline deposits in the retina,followed by progressive atrophy of retinal pigment epithelium (RPE),choriocapillaris and photoreceptors.CYP4V2 has been identified as causative gene for BCD.At present,multiple gene mutation sites have been found in BCD patients.CYP4V2 gene belongs to cytochrome P450,it participates in the ω-hydroxylase activity of polyunsaturated fatty acids (PUFAs).CYP4V2 proteins are mainly distributed in the RPE,docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) as specific catalytic substrates,and play an important role in ocular physiological lipid recycling system.CYP4V2 gene mutations can disrupt the endogenous fatty acids or steroid synthesis and decomposition approach.The treatment of BCD always refers to retinitis pigmentosa (RP),and the study of mutation sites have provided the possibility for future gene therapy.Understanding the mechanism of molecular genetics and the pathophysiology of disease will be useful for the genetic diagnosis of BCD and potential development of genetic therapy in the future.This article reviewed the molecular genetic mechanism of BCD,in vivo expression and role of CYP4V2 in lipid metabolism and the treatment of BCD.
ABSTRACT
Objective This study was carried out to investigate the effect of myocardial insulin resistance on expression of p38 mitogen-activated protein kinase (MAPK) in ischemic heart failure in rat.Methods Male sprague-dawley rats were subjected either to ligation of the left anterior descending artery (LAD) (n =24) or to sham operation (n =24).After two weeks,cardiac size and function were determined by echocardiography.Glucose and fatty acid (FAO) oxidation rates as well as insulin response were measured in the isolated working heart.The protein expression of p38MAPK was evaluated by Western blotting.Results The infarcted hearts were dilated and had a reduced ejection fraction (ejection fraction ＜0.50).The basal glucose oxidation was preserved,but the fatty acid oxidation was significantly reduced.Insulin effect on substrate oxidation was significantly impaired for both the decrease in fatty acid oxidation and the increase in glucose oxidation.The protein expression of p38MAPK in infracted hearts wasfisigni cantly reduced(P＜0.05).Condusion Myocardial infarction in rats caused partial insulin resistance at the level of substrate oxidation,which was associated with cardiac contractile dysfunction and the expression of p38MAPK.