title: Betaine inhibits vascularization via suppression of Akt in the retinas of streptozotocin-induced hyperglycemic rats.
abstract: Diabetic retinopathy is a severe microvascular complication amongst patients with diabetes, and is the primary cause of visual loss through neovascularization. Betaine is one of the components of Fructus Lycii. In the present study, the effects of betaine on the expression levels of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α in association with the Akt pathway were investigated in the retinas of streptozotocin (STZ)-induced diabetic rats using western blot and immunohistochemical analyses. The results of the present study revealed that the expression levels of VEGF, HIF-1α, and Akt were increased in the retinas of the STZ-induced diabetic rats. Betaine treatment attenuated this increase in VEGF and HIF-1α expression via suppression of diabetes-induced Akt activation in the retinas of the diabetic rats. The results suggested that betaine may potentially be used to delay the onset of complications associated with diabetic retinopathy via inhibition of retinal neovascularization in patients with diabetes.
authors.affiliation: Department of Oriental Medical Rehabilitation, Gil Oriental Medical Hospital, College of Oriental Medicine, Gachon University, Incheon 405‑760, Republic of Korea.
authors.forename: Young-Giun
authors.initials: YG
authors.lastname: Kim
authors.affiliation: Department of Oriental Medical Rehabilitation, Gil Oriental Medical Hospital, College of Oriental Medicine, Gachon University, Incheon 405‑760, Republic of Korea.
authors.forename: Hyung-Ho
authors.initials: HH
authors.lastname: Lim
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul, Gyeonggi‑do 130‑701, Republic of Korea.
authors.forename: Suh-Ha
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul, Gyeonggi‑do 130‑701, Republic of Korea.
authors.forename: Mal-Soon
authors.initials: MS
authors.lastname: Shin
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul, Gyeonggi‑do 130‑701, Republic of Korea.
authors.forename: Chang-Ju
authors.initials: CJ
authors.lastname: Kim
authors.affiliation: Department of Anesthesiology and Pain Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Gyeonggi‑do 463‑721, Republic of Korea.
authors.forename: Hyeon Jeong
authors.initials: HJ
authors.lastname: Yang
mesh_terms: D000818:Animals; D001622:Betaine / Q000494:pharmacology*; D001786:Blood Glucose / Q000032:analysis; D003921:Diabetes Mellitus, Experimental / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D007150:Immunohistochemistry; D032305:Lycium / Q000737:chemistry / Q000378:metabolism; D008297:Male; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism; D015861:Retinal Neovascularization; D015398:Signal Transduction / Q000187:drug effects*; D013311:Streptozocin / Q000633:toxicity; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D042461:Vascular Endothelial Growth Factor A; D001622:Betaine; D013311:Streptozocin; D051057:Proto-Oncogene Proteins c-akt