Abstract | Uvod: Adropin je novi peptid povezan s homeostazom energije i vaskularnom zaštitom. Prema našem saznanju, za sada nema studija koje su istraživale vezu adropina i upalnih bolesti crijeva (IBD). Matriks Gla protein je peptid ovisan o vitaminu K sa značajnom ulogom u zaustavljanju vaskularne kalcifikacije. Nedavne studije ukazuju na moguću poveznicu između imunomodulatornog učinka MGP-a i upalne bolesti crijeva.
Cilj: Cilj ove studije je usporedba serumske razine adropina oboljelih od upalnih bolesti crijeva i zdrave kontrolne skupine. Nadalje, istraživali smo povezanost razine adropina sa zbirovima aktivnosti IBD-a, CRP-om, fekalnim kalprotektinom, glukozom na tašte i razinom inzulina. Cilj druge studije je bila uspredba razine inaktivnog MGP između oboljelih od IBD i zdrave kontrolne skupine. Dodatno, namjera je bila istražiti povezanost razine inaktivnog MGP s kliničkim i laboratorijskim parametrima.
Metode: Presječna studija evaluacije serumske razine adropina provedena je na 55 bolesnika s IBD (30 bolesnika s ulceroznim kolitisom, 25 bolesnika s Crohnovom bolesti) uspoređujući s kontrolnom skupinom podudarnih dobnih i spolnih značajki. Presječno istraživanje serumske razine inaktivnog MGP provedena je na 70 bolesnika s IBD-om (30 bolesnika s ulceroznim kolitisom , 40 s Crohnovom bolesti) te na 60 zdravih isipitanika koji pripadaju kontrolnoj skupini podudarnih dobnih i spolnih značajki. Serumska razina adropina određivana je ELISA metodom (dual enzyme-linked immunosorbent assay) za humani adropin (Phoenix Pharmaceuticals, Burlingame, CA, USA), prema uputama proizvođača. Razina inaktivnog MGP analizirana je CLIA metodom koristeći IDS-iSYS InaKtif MGP (Immunodiagnostic Systems, Frankfurt, Germany) prema uputama proizvođača. Razina fekalnog kalprotektina određivana je turbidimetrijskom imunoesej metodom koristeći Buhlmann fCAL turbo assay (Buhlmann Laboratories AG, Schonenbuch, Switzerland). Ostali parametri određivani su standardnim laboratorijskim procedurama.
Rezultati: Serumska razina adropina bila je značajno niža u bolesnika s IBD uspoređujući s kontrolnom skupinom (2.89±0.94 vs 3.37±0.60 ng/mL, P=0.002), dok nije bilo značajne razlike između oboljelih od ulceroznog kolitis i oboljelih od Crohnove bolesti (P=0.585). Nadalje, pronađena je značajna negativna korelacija između adropina i fekalnog kalprotektina (r= -0.303, P=0.025). U ukupnoj populaciji ispitanika pronađena je značajna negativna korelacija razine adropina i glukoze na tašte (r= -0.222, P=0.023). Multivarijatna logisitička regresija pokazala je vrijednost adropin kao značajnog prediktora pozitivnog IBD statusa, navedena s drugim temeljnim značajkama (OR 0.455, 95% CI 0.251-0.823, P=0.009).
Razina inaktivnog MGP bila je značajno viša u bolesnika s IBD uspoređujući s kontrolnom skupinom (629.83 ± 124.20 vs 546.7 ± 122.09 pmol/mL, P < 0.001), a statistički značajne razlike između skupina bolesnika s ulceroznim kolitisom i bolesnika s Crohnovom bolesti nije bilo (640.02 ± 131.88 vs 616.23 ± 113.92 pmol/mL, P = 0.432). Nadalje, utvrđena je značajna pozitivna korelacija između razine inaktivnog MGP i fekalnog kalprotektina (r = 0.396, P < 0.001) kao i između inaktivnog MGP-a i CRP-a (r = 0.477, P < 0.001). Multipla linearna regresijska analiza zadržava statistički značajnu povezanost s fekalnim kalprotektinom (β ± SE, 0.06 ± 0.02, P = 0.003).
Zaključak: Rezultati istraživanja daju naslutiti kako bi adropin mogao biti uključen u složeni patofiziološki proces upalnih bolesti crijeva, ali su potrebna daljna istraživanja koja bi to dodatno potvrdila. Nadalje, rezultati istraživanja razine inaktivnog MGP-a potvrđuju eksperimentalno dobivene podatke o imunomodulacijskom učinku MGP-a na IBD te ukazuju na mogući značaj u nastanku upalnih bolesti crijeva i ekstraintestinalnih manifestacija. |
Abstract (english) | Background: Adropin is a novel peptide mostly associated with energy homeostasis and vascular protection. To our knowledge, there are no studies that investigated its relationship with inflammatory bowel diseases (IBD). Matrix Gla protein (MGP) is a vitamin K dependent peptide which has an established role in suppression of vascular calcification. Recent studies have pointed to a possible link between immunomodulatory effect of MGP and inflammatory bowel disease.
Aim: The aim of this study was to compare serum adropin levels between patients with IBD and healthy controls. Furthermore, we explored adropin levels correlations with IBD severity scores, hsCRP, fecal calprotectin and fasting glucose and insulin levels. The aim of the second study was to compare serum levels of inactive, dephosphorylated and uncarboxylated MGP form (dp-ucMGP) between patients with IBD and healthy controls. The additional goal was to investigate the association of plasma dp-ucMGP levels with the anthropometric, clinical and laboratory parameters.
Methods: This cross-sectional evaluation study of serum adropin levels was conducted on 55 patients with IBD (30 Ulcerative colitis patients, 25 Crohn’s disease patients) in comparison with 50 age and gender matched controls. Furthermore, cross-sectional study of serum dp-ucMGP levels was conducted on 70 patients with IBD (30 patients with ulcerative colitis and 40 patients with Crohn’s disease) and 60 age and gender matching healthy controls. Serum concentrations of adropin were determined using the dual enzyme-linked immunosorbent assay (ELISA) of human adropin (Phoenix Pharmaceuticals, Burlingame, CA, USA), according to the manufacturer's instructions. Plasma dp-ucMGP levels were analyzed from blood samples by CLIA method using IDS-iSYS InaKtif MGP (Immunodiagnostic Systems, Frankfurt, Germany) according to the manufacturer's instructions. FC levels were determined from stool samples by turbidimetric immunoassay method using Buhlmann fCAL turbo assay (Buhlmann Laboratories AG, Schonenbuch, Switzerland). Other parameters were analyzed according to the standard laboratory procedures.
Results: Serum adropin levels were significantly lower in patients with IBD in comparison with 50 controls (2.89±0.94 vs 3.37±0.60 ng/mL, P=0.002), while there was no significant difference in comparison of UC patients with CD patients (P=0.585). Furthermore, there was a negative correlation between adropin and fecal calprotectin (r= -0.303, P=0.025), whereas in the total study population, we found a significant negative correlation with fasting glucose levels (r= -0.222, P=0.023). A multivariable logistic regression showed that serum adropin was a significant predictor of positive IBD status when enumerated along with baseline characteristics (OR 0.455, 95% CI 0.251-0.823, P=0.009).
Plasma levels of dp-ucMGP were significantly higher in patients with IBD compared to the control group (629.83 ± 124.20 vs 546.7 ± 122.09 pmol/mL, P < 0.001), and there was no significant difference between patients with Crohn’s disease and patients with ulcerative colitis (640.02 ± 131.88 vs 616.23 ± 113.92 pmol/mL, P = 0.432). Furthermore, a significant positive correlation of plasma dp-ucMGP levels was found with both fecal calprotectin (FC) levels (r = 0.396, P < 0.001) and high sensitivity C-reactive protein (hsCRP) levels (r = 0.477, P < 0.001). Multiple linear regression analysis showed that dp-ucMGP levels retained significant association with FC (β ± SE, 0.06 ± 0.02, P = 0.003).
Conclusion: Our findings imply that adropin could be involved in complex pathophysiology of IBD, but further larger scale studies are needed to address these findings. Moreover, results with inactive MGP support experimental data of MGP immunomodulatory IBD effect and indicate potential involvement in the pathophysiology of the disease, and possibly extraintestinal manifestations. |