title: Prenatal betaine exposure modulates hypothalamic expression of cholesterol metabolic genes in cockerels through modifications of DNA methylation.
abstract: Cholesterol is essential for neuronal development and brain function. Previously we reported that in ovo administration of betaine modulates hepatic cholesterol metabolism in the chicken, yet it remains unknown whether maternal betaine affects the cholesterol content and the expression of cholesterol metabolic genes in chicken hypothalamus. In this study, eggs were injected with saline or betaine at 2.5 mg/egg, and the hatchlings were raised under the same condition until 64 d of age. Maternal betaine significantly (P = 0.05) increased the body weight and suppressed aggressive behavior of 64-day-old cockerels, in association with significantly (P < 0.05) up-regulated expression of 5-HTR1A receptor in the hypothalamus. Concurrently, betaine in ovo significantly increased (P < 0.05) the hypothalamic content of total cholesterol and cholesterol ester, which coincided with significantly up-regulated (P < 0.05) hypothalamic expression of cholesterol biosynthetic genes, such as sterol-regulatory element binding protein 2 and 3-hydroxy-3-methyl-glutaryl-CoA reductase as well as acetyl-CoA cholesterol acyltransferase 1, which converts free cholesterol to cholesterol ester for storage. In contrast, low density lipoprotein receptor, which mediates the cholesterol uptake, was significantly down-regulated (P < 0.05). In ovo betaine administration significantly enhanced the expression of betaine-homocysteine methyltransferase and DNA methyltransferase 1 (P < 0.05), which was associated with alterations of CpG methylation on the promoter of modified cholesterol metabolic genes. These results indicate that maternal betaine modulates hypothalamic cholesterol metabolism in cockerels through modifying DNA methylation on the promoter of cholesterol metabolic genes.
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Abdulrahman A
authors.initials: AA
authors.lastname: Idriss
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Qinwei
authors.initials: Q
authors.lastname: Sun
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Longfei
authors.initials: L
authors.lastname: Jia
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Yimin
authors.initials: Y
authors.lastname: Jia
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Nagmeldin A
authors.initials: NA
authors.lastname: Omer
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.
authors.forename: Halima
authors.initials: H
authors.lastname: Abobaker
authors.affiliation: Key Laboratory of Animal Physiology & Biochemistry, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, P. R. China.|Jiangsu Collaborative Innovation Centre of Meat Production and Processing, Quality and Safety Control, Nanjing 210095, P. R. China.
authors.forename: Ruqian
authors.initials: R
authors.lastname: Zhao
mesh_terms: D000374:Aggression / Q000187:drug effects; D000818:Animals; D001622:Betaine / Q000008:administration & dosage / Q000494:pharmacology*; D001835:Body Weight / Q000187:drug effects; D002645:Chickens / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002784:Cholesterol / Q000096:biosynthesis* / Q000378:metabolism; D019175:DNA Methylation / Q000187:drug effects*; D005786:Gene Expression Regulation; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D010063:Ovum / Q000187:drug effects / Q000378:metabolism
chemical_list: D001622:Betaine; D002784:Cholesterol
keywords: DNA methylation; betaine; chicken; cholesterol; hypothalamus