Narrow-band ultraviolet B exposure increases serum vitamin D levels in haemodialysis patients

作者：Ala Houhala Meri J^*; Vahavihu Katja; Hasan Taina; Kautiainen Hannu; Snellman Erna; Karisola Piia; Dombrowski Yvonne; Schauber Juergen; Saha Heikki; Reunala Timo

来源：Nephrology Dialysis Transplantation, 2012, 27(6): 2435-2440.

DOI：10.1093/ndt/gfr700

• chronic kidney disease
• haemodialysis
• ultraviolet B radiation
• vitamin D

Background. Chronic kidney disease (CKD) patients are especially prone to vitamin D insufficiency. Narrow-band ultraviolet B (NB-UVB) treatment increases serum 25-hydroxyvitamin D [25(OH) D] in dermatological patients, and we studied whether it also improves vitamin D balance in CKD patients on haemodialysis. %26lt;br%26gt;Methods. Fifteen dialysis patients (mean age 48.3 years) and 12 healthy subjects (mean age 43.6 years) received nine NB-UVB exposures on the upper body. Serum 25(OH) D and 1,25(OH) 2D were measured before and after the exposures. From skin biopsy specimen messenger RNA (mRNA) expression levels of CYP24A1 and CYP27B1, two enzymes needed for hydroxylation of vitamin D into its active metabolites, and of antimicrobial peptide cathelicidin, were examined. %26lt;br%26gt;Results. Before NB-UVB, mean serum 25(OH) D was 32.5 +/- 10.2 nmol/L in the dialysis patients and 60.2 +/- 18.0 nmol/L in the healthy subjects (P %26lt; 0.001). After eight NB-UVB exposures, serum 25(OH) D increased by 13.8 nmol/L (43%; P %26lt; 0.001) and serum 1,25(OH) 2D by 3.3 pmol/L (27%; P = 0.002) in the dialysis patients. After NB-UVB exposures, CYP27B1 mRNA was increased (P = 0.04), whereas cathelicidin mRNA was decreased (P %26lt; 0.0001) compared to non-treated healthy subjects. One and 2 months after NB-UVB exposure, serum 25(OH) D was still 10% higher than initially in the dialysis patients. %26lt;br%26gt;Conclusions. The present study shows that a short course of NB-UVB exposure increases significantly serum 25(OH) D and 1,25(OH) 2D in dialysis patients. The effect is, however, short lasting suggesting that the patients need cyclic NB-UVB exposure to maintain their improved vitamin D concentration.

• 出版日期2012-6