sample source: Eight-week old male C57BL/6 mice, purchased from the Jackson Laboratory tissue: heart left ventricle protocol: exercise-induced cardiac hypertrophy
Biomaterial provider
Garnering Innovation Lab at UTSW
Treatment protocol
Pathological cardiac hypertrophy was investigated using the isoproterenol-induced subacute myocardial injury model as previously described [28]. Briefly, animals were anesthetized with 1.5% isoflurane (Smiths Medical PM, Waukesha, WI) in 98.5% oxygen and a 1 cm incision made on the back of each animal between the shoulder blades. An Alzet 1007D micro-osmotic pump (DURECT Corporation, Cupertino, CA) containing isoproterenol (ISO, Sigma-Aldrich, St. Louis, MO), at 40 mg.kg-1.d-1, dissolved in 0.9% NaCl was inserted into the infrascapular subcutaneous tissue and the incision sutured. After 10 days of ISO administration, mice were sacrificed, and left ventricles were collected and processed for subsequent assays. Experimental physiological cardiac hypertrophy was induced via exercise, as previously described [29]. Briefly, mice were placed in buckets of pre-warmed water maintained at ~30 oC with low-watt heat lamps and allowed to swim for 90 minutes twice daily. At the beginning of the experiment, mice were acclimated to the exercise routine gradually, beginning with 10 minutes twice daily and increasing in increments of 10 minutes per day, until 90 minutes was obtained. After 8 weeks of swimming, mice were sacrificed and heart samples (left ventricles) collected and processed for each assay. Sedentary mice confined to cages served as negative controls.
Growth protocol
All mice were housed in the Animal facility at University of Texas Southwestern Medical Center (UTSW), Dallas, TX, in accordance with the standards set forth in the Guide for the Care and Use of Laboratory Animals (NIH Publication No. 85-23, revised 1996). All experimental procedures for this study were approved by the Institutional Animal Care and Use Committee at UTSW.
Extracted molecule
total RNA
Extraction protocol
Total RNA from left ventricles of experimental animals was isolated using TRIzol Reagent (Invitrogen Corporation, Carlsbad, CA) per manufacturer’s instructions and purified by phenol-chloroform extraction and ethanol precipitation.
Label
per manufacturer, in UTSW Microarray Core
Label protocol
per manufacturer, in UTSW Microarray Core
Hybridization protocol
per manufacturer, in UTSW Microarray Core
Scan protocol
per manufacturer, in UTSW Microarray Core
Description
Study was performed to compare pathological versus physiological cardiac hypertrophy
Data processing
Data were analyzed using GeneSifter (VizX Labs, Seattle, WA) and Spotfire DecisionSite 9.0 (Spotfire, Inc., Somerville, MA). Data were normalized using robust-multi average (RMA) method, and signals for each group were averaged before performing Student’s t test with Benjamini and Hochberg correction and pairwise comparisons for sedentary mice versus mice that received ISO treatment or were exercised. Genes were considered as altered if the folds-change was at least 1.5 and adjusted p value ≤ 0.05.
