Down-regulation of monocyte functions by treatment of healthy adults with 1 alpha,25 dihydroxyvitamin D3.
A number of in vitro studies suggest an immunoregulatory role of 1 alpha,25 Dihydroxyvitamin D3 (1,25-(OH)2D3). The hormone inhibits production of interleukin-2 and immunoglobulin, and it blocks lymphocyte proliferation. Diverse effects on monocyte functions have been reported. However, immunological effects of 1,25-(OH)2D3 have not been substantiated in vivo. Six healthy male volunteers, aged 28-45 yr, were treated orally with 1,25-(OH)2D3 (tabl. Rocaltrol), 1 microgram twice daily for 7 days. Blood and urine samples were collected before and 7 days after initiation of treatment. Blood mononuclear cells from individuals treated with 1,25-(OH)2D3 showed a significantly reduced production of both interleukin-1 alpha (45%) and tumor necrosis factor-alpha (58%) (both measured by ELISA). Interleukin-6, production, measured by the B9 cell assay, was reduced in five individuals (78%), and unchanged in one. There was no effect on the release of interleukin-1 beta. There was no measurable effect on interleukin-2, interferon gamma or immunoglobulin production, or on mitogen-induced proliferation of blood mononuclear cells. Serum-osteocalcin and urine excretion of calcium were increased to 131 and 173%, respectively. The serum-calcium and serum-phosphate levels were unchanged.
Müller
K
K
Laboratory of Medical Immunology, Rigshospitalet State University Hospital, Copenhagen, Denmark.
Gram
J
J
Bollerslev
J
J
Diamant
M
M
Barington
T
T
Hansen
M B
MB
Bendtzen
K
K
D000284:Administration, Oral; D000328:Adult; D001402:B-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D002117:Calcitriol / Q000097:blood / Q000494:pharmacology*; D016207:Cytokines / Q000096:biosynthesis*; D015536:Down-Regulation; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D007371:Interferon-gamma / Q000096:biosynthesis; D007375:Interleukin-1 / Q000096:biosynthesis / Q000097:blood; D015850:Interleukin-6 / Q000096:biosynthesis / Q000097:blood; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects* / Q000378:metabolism; D015675:Osteocalcin / Q000097:blood; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D016207:Cytokines; D007136:Immunoglobulins; D007375:Interleukin-1; D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D015675:Osteocalcin; D007371:Interferon-gamma; D002117:Calcitriol