ビタミンDの代謝調節と体内時計の関与について

In chronic renal failure patients and dialysis patients, hyperphosphatemia and hypovitaminosis occur due to impaired urinary phosphorus excretion and vitamin D activation, leading to secondary hyperparathyroidism and renal osteodystrophy.These events can lead to severe ectopic calcification in blood vessels and the heart, increasing the risk of cardiovascular disease and death.In recent years, approximately half of patients undergoing dialysis have diabetes, so it is important to prevent the progression to diabetic nephropathy as one of the three major complications. Furthermore, it has been reported that hyperphosphatemia increases the risk of developing heart failure and death even when renal function is normal, and blood concentrations of phosphorus and 1，25（OH）2D, the active form of vitamin D, have a circadian rhythm. Therefore, quantitative, qualitative, and temporal nutritional management of dietary phosphorus during a wide range of life stages from healthy to disease is important for maintaining homeostasis of vitamin D, calcium, and bone metabolism, and for preventing the onset and progression of kidney disease, not only is it useful, but it is also thought to be useful in preventing lifestyle-related diseases such as diabetes and inflammatory diseases from becoming more severe. In this article, we will discuss vitamin D deficiency/insufficiency in renal disease, its relationship with circadian rhythms, energy and cholesterol metabolism revealed through research on the regulation of vitamin D metabolism, differences in phosphorus sensitivity at life stages.