Effect of ouabain on myocardial ultrastructure and cytoskeleton during the development of ventricular hypertrophy

Abstract

The aim of this work is to study cytoskeletal impairment during the development of ouabain-induced ventricular hypertrophy. Male Sprague-Dawley rats were treated with either ouabain or saline. Systolic blood pressure (SBP) was recorded weekly. At the end of the 3rd and 6th week, the rats were killed and cardiac mass index were measured. Hematoxylin-eosin and Sirius red staining were carried out and cardiac ultrastructure were studied using transmission electron microscopy. The mRNA level of Profilin-1, Desmin, PCNA, TGF-β(1) and ET-1 in the left ventricle were measured using real-time quantitative PCR while their protein levels were examined by Western blot or immunohistochemistry. After 3 weeks, there was no significant difference in the mean SBP, cardiac mass index, mRNA and protein expression of PCNA, TGF-β(1) and ET-1 between the two groups. However, ouabain-treated rats showed disorganized cardiac cytoskeleton with abnormal expression of Profilin-1 and Desmin. After 6 weeks, the cardiac mass index remained the same in the two groups while PCNA, TGF-β(1), and ET-1 have been upregulated in ouabain-treated rats. The cardiac cytoskeletal impairment was more severe in ouabain-treated rats with further changes of Profilin-1 and Desmin. Cytoskeletal abnormality is an ultra-early change during ouabain-induced ventricular hypertrophy, before the release of hypertrophic factors. Therapy for prevention of ouabain-induced hypertrophy should start at the early stage by preventing the cytoskeleton from disorganization.

Plectin protects podocytes from adriamycin‐induced apoptosis and F‐actin cytoskeletal disruption through the integrin α6β4/FAK/p38 MAPK pathway

“…The sections were then treated with peroxidase‐marked streptavidin/peroxidase before examination under an Olympus microscope (model BX‐51; Tokyo, Japan). We used a semiquantitative scoring system to grade the intensity of the abovementioned immunoreactions. In each glomerulus, positively stained cells were scored according to their staining intensities, which were determined using the following scale: 0 (no staining), +1 (weak but detectable staining), +2 (moderate staining) and +3 (intense staining).…”

“…Data shown are representative of five independent experiments (n = 5). The ADR-treated podocyte in C-G were treated with 0.5 μg/mL ADR for 12 h. ADR, adriamycin; NC, normal control; FITC, fluorescein isothiocyanate; F-actin, filamentous actin semiquantitative scoring system 15,16 to grade the intensity of the abovementioned immunoreactions. In each glomerulus, positively stained cells were scored according to their staining intensities, which were determined using the following scale: 0 (no staining), +1…”

The presence of mu-, delta-, and kappa-opioid receptors in human heart tissue

“…Experimental studies have shown that stimulation of both peripheral (cardiac) and central opioid receptors (ORs) is able to modulate heart function and evoke cardioprotection against ischemia [5][6][7]. The efficacy of opioids in inducing preconditioning and postconditioning not only in intact hearts in vivo [8] but also in isolated cardiomyocytes in vitro [9,10], their inotropic effects [11][12][13], and their impact on growth factor expression [14,15] in cell culture indicate the presence of ORs on cardiomyocytes and not only on neural elements.…”

Cofilin1 is involved in hypertension-induced renal damage via the regulation of NF-κB in renal tubular epithelial cells

“…The nuclear and cytoplasmic proteins of the HK-2 cells were extracted using a commercially available assay kit (Byotime, Shanghai, China). The total proteins of the HK2 cells and renal cortex were extracted as published previously [ 15 , 16 ]. The protein concentrations were determined using a BCA assay kit (Byotime, Shanghai, China) as instructed.…”