title: A synergistic, balanced antioxidant cocktail, protects aging rats from insulin resistance and absence of meal-induced insulin sensitization (AMIS) syndrome.
abstract: A series of in vivo and in vitro studies using animal and human models in the past 15 years have demonstrated that approximately 55% (~66% in humans) of the glucose disposal effect of an i.v. injection of insulin in the fed state is dependent on the action of a second hormone, hepatic insulin sensitizing substance (HISS), which is released from the liver and stimulates glucose uptake in muscle, heart and kidneys. Sensitization of the insulin response by a meal through release of HISS is called meal-induced insulin sensitization (MIS). Absence of HISS action results in postprandial hyperglycemia, hyperinsulinemia, hyperlipidemia, adiposity, increased free radical stress and a cluster of progressive metabolic and cardiovascular dysfunctions referred to as the AMIS (absence of meal-induced insulin sensitization) syndrome. Reduced HISS release accounts for the insulin resistance that occurs with aging and is made worse by physical inactivity and diets high in sucrose or fat. This brief review provides an update of major metabolic disturbances associated with aging due to reduction of HISS release, and the protection against these pathological changes in aging animals using a balanced synergistic antioxidant cocktail SAMEC (S-adenosylmethionine, vitamins E and C). The synergy amongst the components is consistent with the known benefits of antioxidants supplied by a mixed diet and acting through diverse mechanisms. Using only three constituents, SAMEC appears suitable as an antioxidant specifically targeting the AMIS syndrome.
authors.affiliation: Department of Pharmacology & Therapeutics, College of Medicine, Faculty of Health Sciences, University of Manitoba, A224-753 McDermot Avenue, Winnipeg, MB R3E 0T6, Canada. h.helen.wang@med.umanitoba.ca.
authors.forename: Hui Helen
authors.initials: HH
authors.lastname: Wang
authors.affiliation: Department of Pharmacology & Therapeutics, College of Medicine, Faculty of Health Sciences, University of Manitoba, A224-753 McDermot Avenue, Winnipeg, MB R3E 0T6, Canada. kawshik88@yahoo.com.
authors.forename: Kawshik K
authors.initials: KK
authors.lastname: Chowdhury
authors.affiliation: Department of Pharmacology & Therapeutics, College of Medicine, Faculty of Health Sciences, University of Manitoba, A224-753 McDermot Avenue, Winnipeg, MB R3E 0T6, Canada. wlautt@cc.umanitoba.ca.
authors.forename: W Wayne
authors.initials: WW
authors.lastname: Lautt
mesh_terms: D000375:Aging / Q000473:pathology*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology*; D007333:Insulin Resistance; D020011:Protective Agents / Q000494:pharmacology*; D051381:Rats; D013577:Syndrome
chemical_list: D000975:Antioxidants; D007328:Insulin; D020011:Protective Agents