title: Chronic glucagon-like peptide-1 infusion sustains left ventricular systolic function and prolongs survival in the spontaneously hypertensive, heart failure-prone rat.
abstract: BACKGROUND
  Glucagon-like peptide-1 (GLP-1) treatment leads to short-term improvements in myocardial function in ischemic and nonischemic cardiomyopathy. It is unknown whether GLP-1 improves survival when administered over a longer time period. Spontaneously hypertensive, heart failure-prone (SHHF) rats progress to advanced heart failure and death over a 15-month period. The authors sought to determine whether a continuous infusion of GLP-1 would reduce mortality in this model.
  
  
  RESULTS
  At 9 months of age, 50 SHHF rats were randomized to receive a 3-month, continuous infusion of either GLP-1 or saline. Metabolic parameters were measured and cardiac ultrasounds performed at study initiation and completion of treatment. Surviving rats were euthanized at 12 months. Hearts were perfused in an isolated, isovolumic heart preparation, and Tunel staining of myocardial samples was performed. Baseline metabolic and cardiac functional parameters were comparable. GLP-1-treated SHHF rats had greater survival (72% versus 44%, P=0.008) at 12 months of age. In addition, GLP-1 treatment led to higher plasma insulin, lower plasma triglycerides, and preserved left ventricular (LV) function. GLP-1-treated rats demonstrated decreased myocyte apoptosis by Tunel staining as well as reduced caspase-3 activation. No increase in p-BAD expression was seen. In isolated hearts, the LV systolic pressure and LV-developed pressure were greater in the GLP-1 group. Myocardial glucose uptake was also increased in GLP-1-treated SHHF rats.
  
  
  CONCLUSIONS
  Chronic GLP-1 treatment prolongs survival in obese SHHF rats. This is associated with preserved LV function and LV mass index, increased myocardial glucose uptake, and reduced myocyte apoptosis.
authors.affiliation: Department of Medicine, Allegheny General Hospital, Pittsburgh, Pa, USA.
authors.forename: Indu
authors.initials: I
authors.lastname: Poornima
authors.forename: Suzanne B
authors.initials: SB
authors.lastname: Brown
authors.forename: Siva
authors.initials: S
authors.lastname: Bhashyam
authors.forename: Pratik
authors.initials: P
authors.lastname: Parikh
authors.forename: Hakki
authors.initials: H
authors.lastname: Bolukoglu
authors.forename: Richard P
authors.initials: RP
authors.lastname: Shannon
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D052216:Glucagon-Like Peptide 1 / Q000008:administration & dosage*; D006333:Heart Failure / Q000188:drug therapy* / Q000401:mortality / Q000503:physiopathology; D054795:Incretins / Q000008:administration & dosage*; D007262:Infusions, Intravenous; D016684:Prone Position; D051381:Rats; D011918:Rats, Inbred SHR; D015996:Survival Rate / Q000639:trends; D013599:Systole; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000187:drug effects* / Q000502:physiology
chemical_list: D054795:Incretins; D052216:Glucagon-Like Peptide 1