<b>Bone marrow macrophage-exosomes with HuR deficiency limits ANG-II induced cardiac fibrosis and LV dysfunction in mice</b>

Injection of diabetic (db/db) bone marrow macrophage-exosomes with HuR deficiency preserves LV function in ANG-II treated mice. Clodronate liposome or control liposome (150 μL; FormuMax Scientific, Sunnyvale, CA, USA) was intraperitoneally injected into 8-weeks old C57BL/6J mice and macrophage depletion was confirmed using FACS analysis (BD LSR II Analyzer). After 48 hours, vehicle (saline) or ANG II (1000 ng.kg−1.min−1; EMD Millipore) was continuously administered using osmotic mini-pumps (ALZET DURECT, Cupertino, CA). Exosomes from Control or HuR shRNA- treated BMMØ derived from diabetic (db/db) mice (Exo-db/dbHuR KD vs Exo-db/dbWT) were injected intravenous through tail vein on day 2 and day 4 after pump implantation. Heart function was evaluated by echocardiography (Vevo 2100; VisualSonics, Toronto, Canada). Mice were euthanized on day 28; heart was collected for further analysis. Transthoracic two-dimensional B-Mode and M-Mode echocardiogram was obtained using Vevo 2100 (VisualSonics, Toronto, Canada) equipped with 30 MHz transducer. Echocardiographic studies were performed after ANG II mini- osmotic pump implantation on mice anesthetized with a mixture of 1.5% isoflurane and oxygen (1 L/min). B-Mode and M-Mode tracings were used to measure left ventricle (LV) percent fractional shortening (%FS) and percent ejection fraction (�) respectively. Observation: Echocardiography analysis showing improvements in heart function as shown by higher % ejection fraction and % fractional shortening in mice receiving Exo- db/dbHuR KD. The full dataset is uploaded as an excel spreadsheet file. Masson’s Trichrome staining and analysis showing lower interstitial fibrosis in hearts of mice receiving diabetic (db/db) BMMØ-exosomes with HuR deficiency (Exo-db/dbHuR KD), as compared to db/db-Exo injected mice at 28 days post-administration. The full dataset is attached as a spreadsheet.