Circulating interferon-γ correlates with 1,25(OH)D and the 1,25(OH)D-to-25(OH)D ratio.
The mechanism responsible for the decrease in vitamin D status (i.e., plasma or serum 25-hydroxyvitamin D (25(OH)D) concentration) during inflammatory stress is unknown in humans. Interferon (IFN)-γ is an inflammatory cytokine that regulates vitamin D metabolism in isolated immune cells, but data suggesting this regulation exists in vivo is lacking. The purpose of this study, therefore, was to associate circulating IFN-γ perturbations with 25(OH)D and 1,25-dihydroxyvitamin D (1,25(OH)D) alterations during inflammatory stress in young adults recovering from anterior cruciate ligament (ACL) reconstruction. Plasma 25(OH)D, 1,25(OH)D and IFN-γ concentrations were measured in fasting blood draw samples obtained from twelve-male patients pre-surgery and 90-m, 3-d and 7-d post-surgery. 25(OH)D decreased significantly (p<0.05) after surgery, and strikingly, tended to inversely correlate (r=-0.32, p=0.058) with IFN-γ changes from pre- to post- (i.e., 90-m, 3-d, and 7-d) surgery. Additionally, 1,25(OH)D (r=0.37, p<0.05) and the 1,25(OH)D-to-25(OH)D ratio (r=0.52, p<0.05) changes from pre- to post- (i.e., 90-m, 3-d, and 7-d) surgery correlated with those of IFN-γ. These are the first reported in vivo findings suggesting that the 25(OH)D decrease and conversion to 1,25(OH)D increase with increasing IFN-γ in the circulation. We conclude that IFN-γ contributes to the decrease in vitamin D and the conversion of vitamin D to its active hormonal form in the circulation during inflammatory insult in humans.
The Orthopedic Specialty Hospital, Murray, UT 84107, USA. tyler.barker@imail.org
Tyler
T
Barker
Thomas B
TB
Martins
Carl R
CR
Kjeldsberg
Roy H
RH
Trawick
Harry R
HR
Hill
D000328:Adult; D000704:Analysis of Variance; D059549:Anterior Cruciate Ligament Reconstruction; D006801:Humans; D007249:Inflammation / Q000097:blood* / Q000175:diagnosis; D007371:Interferon-gamma / Q000097:blood*; D008297:Male; D011184:Postoperative Period; D057234:Preoperative Period; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; D007371:Interferon-gamma; C104450:25-hydroxyvitamin D