ACTA1 and cardiac hypertrophy: Results: TAC induced significant cardiac hypertrophy and fibrosis, accompanied by elevated expression of fibrotic (CTGF, DDR2, α-SMA, collagen I), inflammatory (CD68, CD44, Gal3), apoptotic (Bax, cleaved caspase-3), and endoplasmic reticulum stress markers (GRP78, ATF4).