title: Inhibition of diabetic-cataract by vitamin K1 involves modulation of hyperglycemia-induced alterations to lens calcium homeostasis.
abstract: This study investigated the potential of vitamin K1 against streptozotocin-induced diabetic cataract in Wistar rats. A single, intraperitoneal injection of streptozotocin (STZ) (35 mg/kg) resulted in hyperglycemia, accumulation of sorbitol and formation of advanced glycation end product (AGE) in eye lens. Hyperglycemia in lens also resulted in superoxide anion and hydroxyl radical generation and less reduced glutathione suggesting oxidative stress in lens. Hyperglycemia also resulted in increase in lens Ca2+ and significant inhibition of lens Ca2+ ATPase activity. These changes were associated with cataract formation in diabetic animals. By contrast treatment of diabetic rats with vitamin K1 (5 mg/kg, sc, twice a week) resulted in animals with partially elevated blood glucose and with transparent lenses having normal levels of sorbitol, AGE, Ca2+ ATPase, Ca2+, and oxidative stress. Vitamin K 1 may function to protect against cataract formation in the STZ induced diabetic rat by affecting the homeostasis of blood glucose and minimizing subsequent oxidative and osmotic stress. Thus, these results show that Vitamin K1 inhibits diabetic-cataract by modulating lens Ca2+ homeostasis and its hypoglycemic effect through its direct action on the pancreas.
authors.affiliation: Department of Bioengineering, School of Chemical & Biotechnology, SASTRA University, Thanjavur 613 401, India.
authors.forename: M K N
authors.initials: MK
authors.lastname: Sai Varsha
authors.affiliation: Department of Bioengineering, School of Chemical & Biotechnology, SASTRA University, Thanjavur 613 401, India; Centre for Research on Infectious Diseases (CRID), School of Chemical & Biotechnology, SASTRA University, Thanjavur 613 401, India. Electronic address: raman@biotech.sastra.edu.
authors.forename: Thiagarajan
authors.initials: T
authors.lastname: Raman
authors.affiliation: Department of Zoology, University of Madras, Guindy Campus, Chennai 600 025, India.
authors.forename: Ramar
authors.initials: R
authors.lastname: Manikandan
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D002386:Cataract / Q000378:metabolism / Q000517:prevention & control*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism / Q000517:prevention & control*; D005978:Glutathione / Q000378:metabolism; D017127:Glycation End Products, Advanced / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology*; D017665:Hydroxyl Radical / Q000378:metabolism; D006943:Hyperglycemia / Q000378:metabolism*; D007908:Lens, Crystalline / Q000378:metabolism*; D008297:Male; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D013012:Sorbitol / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D010837:Vitamin K 1 / Q000627:therapeutic use*; D014815:Vitamins / Q000627:therapeutic use*
chemical_list: D001786:Blood Glucose; D017127:Glycation End Products, Advanced; D014815:Vitamins; D013481:Superoxides; D017665:Hydroxyl Radical; D013012:Sorbitol; D010837:Vitamin K 1; D000252:Calcium-Transporting ATPases; D005978:Glutathione; D002118:Calcium
keywords: Calcium; Calcium ATPase; Diabetic cataract; Natural product; Oxidative stress; Vitamin K1