Gggtga Acg Ggggca

I Transcription f regulation mRNA levels '

+ CaBP + ECaC + 24(OH)ase \ Osteocalcin + Osteopontin + RANKL f Alk Pase t p21 t p27 t PSA + Collagen + PTH

""^calcium transport


^Bone metabolism

Intracellular -calcium modulation

Regulation ^of cell proliferation & differentiation

Figure 6 A schematic representation of the mechanism of action of 1,25(OH)2D in various target cells resulting in a variety of biological responses. The free form of 1,25(OH)2D3 enters the target cell and interacts with its nuclear vitamin D receptor (VDR), which is phosphorylated (Pi). The 1,25(OH)2D-VDR complex combines with the retinoic acid X receptor (RXR) to form a hetero-dimer, which, in turn, interacts with the vitamin D responsive element (VDRE), causing an enhancement or inhibition of transcription of vitamin D-responsive genes including calcium-binding protein (CaBP), ECaC, 24-OHase, RANKL, alkaline phosphatase (alk Pase), prostate-specific antigen (PSA), and PTH.

the reason why activated vitamin D compounds are now routinely used for the treatment of the hyperpro-liferative skin disorder psoriasis.

Evaluation for and Consequences of Vitamin D Deficiency

Vitamin D deficiency in young children causes rickets. As a child becomes vitamin D deficient, this results in a decrease in the efficiency of intestinal calcium absorption. There is a decline in blood-ionized calcium, which causes the parathyroid glands to produce and secrete more parathyroid hormone (PTH). PTH tries to conserve calcium by enhancing tubular reabsorption of calcium in the kidney. However, in the face of developing hypocalcemia, which could disturb neuromuscular function and a wide variety of metabolic and cellular processes, the body calls upon 1,25(OH)2D and PTH to mobilize stem cells to become functional osteoclasts, which, in turn, mobilize calcium from the skeleton. In addition, PTH causes a loss of phosphorus into the urine causing hypophosphatemia. Thus, in early vitamin D deficiency the serum calcium is normal; it is the low serum phosphorus that causes the extracellular CaXPO4 to be too low for normal mineralization of d

Natural Treatments For Psoriasis

Natural Treatments For Psoriasis

Do You Suffer From the Itching and Scaling of Psoriasis? Or the Chronic Agony of Psoriatic Arthritis? If so you are not ALONE! A whopping three percent of the world’s populations suffer from either condition! An incredible 56 million working hours are lost every year by psoriasis sufferers according to the National Psoriasis Foundation.

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