Calcitriol modulation of cardiac contractile performance via protein kinase C

Interplay of vitamin D and metabolic syndrome: A review

“…Increased vitamin D receptor cells expression in myocardial hypertrophy supports the crucial role of vitamin D for myocardial health [123,124]. The activation of VDR further enhances cardiac calcium flux thereby inducing a rapid relaxation of cardiomyocytes, which may improve diastolic function of the heart [123,125]. Moreover, the regulation of cardiac extracellular matrix turnover by the help of vitamin D may be important to maintain cardiac health [126].…”

Vitamin D deficiency and myocardial diseases

“…It was shown that protein kinase C mediated the phosphorylation of Troponin T, which decreases myofilament Ca 21 sensitivity, and of phospholamban, which increases Ca 21 sequestration into the sarcoplasmatic reticulum. These effects are mainly responsible for the acute (nongenomic) effects of calcitriol on myocardial contractility [35]. Sustained effects of calcitriol on myocyte relaxation were independent of phosphorylation of Ca 21 cycling proteins and remain to be explored in further studies.…”

“…This uptake was mediated by nongenomic effects leading to the opening of Ca 21 channels, and by genomic effects requiring the de novo synthesis of proteins related to Ca 21 cycling in the myocardium [32][33][34]. 1,25(OH)2D effects on cardiac contractility and intracellular calcium handling were studied in adult rat cardiomyocytes [35]. The main finding was an accelerated relaxation in response to acute (5-60 min) and sustained (for at least 2 days) administration of calcitriol [35].…”

“…1,25(OH)2D effects on cardiac contractility and intracellular calcium handling were studied in adult rat cardiomyocytes [35]. The main finding was an accelerated relaxation in response to acute (5-60 min) and sustained (for at least 2 days) administration of calcitriol [35]. It was shown that protein kinase C mediated the phosphorylation of Troponin T, which decreases myofilament Ca 21 sensitivity, and of phospholamban, which increases Ca 21 sequestration into the sarcoplasmatic reticulum.…”

Vitamin D and Skeletal Muscle Function

“…Recently, it has also been shown that 1,25(OH) 2 D induces a rapid direct effect on contraction of isolated individual cardiomyocytes [112]. Moreover, the hormone was found to decrease the stimulated peak of contraction or sarcomere shortening of the isolated heart muscle cells [113]. It is known that the rate of calcium influx through calcium channels is responsible for the rate of myocyte contraction and these calcium channels are located primarily at the t-tubules.…”