Osteoprotegerin, s-RANKL, and selected interleukins in the pathology of bone metabolism in patients with Crohn's disease.
BACKGROUND
Crohn's disease (CD) promotes the development of osteopaenia/osteoporosis, the cytokine background of which is not fully known.


OBJECTIVE
Evaluation of bone mineral density (BMD), the prevalence of osteopaenia and osteoporosis, and the determination of the levels of selected interleukins (IL), osteoprotegerin (OPG), and s-RANKL proteins in patients with CD in relation to a control group and assessment of the relationship between the tested cytokines, OPG, s-RANKL, and BMD.


METHODS
Thirty-seven CD patients and 37 healthy volunteers (control group) were enrolled into the study. Densitometry of the lumbar spine (L2-L4) and of the femoral neck using the DXA technique was carried out. Serum levels of: IL-13, IL-4, IL-17, IL-1β, OPG, and s-RANKL were determined using the ELISA method. Progression-of-disease questionnaires were collected.


RESULTS
The prevalence of osteoporosis and osteopaenia in the CD group was: 18.92% and 32.43% in L2-L4; 13.51% and 35.13% in the neck, respectively. The IL-13 and IL-1β concentrations were significantly higher and OPG was significantly lower in CD patients when compared to controls. In the case of all subjects: IL-13 correlated negatively with the BMD of the neck, IL-17 correlated negatively with the Z-score of L2-L4, and OPG correlated negatively with the IL-13. In the case of CD patients, IL-4 correlated negatively with the BMD of L2-L4.


CONCLUSIONS
The incidence of osteopaenia and osteoporosis in Polish CD patients is high. IL-13, IL-1β, and IL-4 seem to be connected with the pathology of decreased BMD in CD. It can be hypothesised that IL-13 may lower BMD by modulating OPG.
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Iwona
I
Krela-Kaźmierczak
Department of Clinical Biochemistry and Laboratory Medicine, Poznan University of Medical Sciences, Poznan, Poland.
Ewa
E
Wysocka
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Aleksandra
A
Szymczak
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Piotr
P
Eder
Department of Computer Science and Statistics, Poznan University of Medical Sciences, Poznan, Poland.
Michał
M
Michalak
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Liliana
L
Łykowska-Szuber
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Kamila
K
Stawczyk-Eder
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Katarzyna
K
Klimczak
Department of Gastroenterology, Human Nutrition and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland.
Krzysztof
K
Linke
Department of Family Medicine, Poznan University of Medical Sciences, Poznan, Poland.
Wanda
W
Horst-Sikorska
Crohn's disease; interleukins; osteoporosis; osteoprotegerin; s-RANKL