Resistin: another rising biomarker in inflammatory bowel disease?

Association of circulating resistin and adiponectin levels with Kawasaki disease: A meta-analysis

The present meta-analysis was performed to examine the association between circulating blood adipokine levels and Kawasaki disease (KD). Studies were identified by searching various databases, including Web of Science, EMBASE, PubMed, Wanfang and China National Knowledge Infrastructure. After the studies were pooled, the mean difference (MD) and corresponding 95% CI were calculated. Subgroup analyses and publication bias detection were also performed. The Cochrane Q test and I² statistics were performed using Review Manager software (version 5.3) to test for heterogeneity. A Begg's test was used to assess publication bias and STATA software (version 12.0) was used for statistical analysis. The results revealed that the KD group exhibited higher levels of resistin compared with those in the healthy controls or disease controls (non-KD; MD=20.76, 95% CI=16.16-25.36, P<0.001; MD=21.27, 95% CI=14.24-28.29, P<0.001, respectively). In addition, when compared with those in patients exhibiting non-coronary artery lesions (NCAL), those with coronary artery lesions (CAL) had higher levels of adiponectin and resistin (MD=1.00, 95% CI=0.06-1.96, P=0.04; MD=2.77, 95% CI=1.32-4.22, P<0.001). Furthermore, compared with those in the inactive-phase group, patients in the active-phase group exhibited higher levels of resistin (MD=17.73, 95% CI=12.82-22.65, P<0.001). In conclusion, the present meta-analysis indicated that resistin levels were elevated in patients with KD. It was also revealed that circulating resistin and adiponectin levels in the CAL group were significantly increased compared with those in patients with NCAL. Furthermore, the active group had higher levels of resistin than the inactive group. The results of these meta-analyses indicated that resistin may serve an important role in the pathogenesis of KD and may therefore be used as biomarkers for the diagnosis of KD, whereas adiponectin may only serve an important role in the pathogenesis of CAL and may therefore be used as a biomarker to distinguish CAL from NCAL.

Hypertrophic Mesenteric Adipose Tissue May Play a Role in Atherogenesis in Inflammatory Bowel Diseases

BACKGROUND

Adipokines released by the adipose tissue are known to play a role in atherogenesis. The hypertrophic mesenteric fat in patients with inflammatory bowel diseases (IBD) also produces adipokines that are considered to play a role in intestinal inflammation. Whether they also contribute to accelerated atherosclerosis in IBD is unknown. The aim of this study was to assess the role of 2 adipokines, resistin and adiponectin, in IBD.

METHODS

We previously published data on 3 markers of cardiovascular risk, carotid intima-media thickness, carotid-femoral pulse wave velocity, and lipoprotein-associated phospholipase A2, in 44 patients with IBD and 44 controls matched for established cardiovascular risk factors. In this study, we measured resistin and adiponectin levels, and assessed their correlations with carotid intima-media thickness, pulse wave velocity, and lipoprotein-associated phospholipase A2.

RESULTS

Resistin levels were significantly higher in patients with IBD (13.7 versus 10 ng/mL; P = 0.022), but there was no difference in adiponectin levels. Resistin levels were significantly higher in patients with active disease compared with those in remission (18.9 versus 11.3 ng/mL; P = 0.014). Adiponectin levels were significantly lower in Crohn's disease compared with ulcerative colitis (6736.3 ± 3105 versus 10,476.1 ± 5575.7 ng/mL; P = 0.026). Adiponectin correlated inversely with pulse wave velocity (rho = -0.434; P < 0.0005) and carotid intima-media thickness (rho = -0.255; P = 0.021).

CONCLUSIONS

This is the first study to suggest that adipokines produced by the hypertrophic mesenteric fat in IBD may play a role not only in intestinal inflammation but also in atherogenesis. Resistin has mainly pro-inflammatory properties, whereas adiponectin likely exerts an angioprotective effect.

Circulating ghrelin levels and obestatin/ghrelin ratio as a marker of activity in ulcerative colitis

Background/Aims

Ghrelin levels are known to increase in patients with ulcerative colitis (UC), but serum obestatin levels in UC patients are not well elucidated. The aim of this study was to examine the relationship between serum ghrelin and obestatin levels and disease activity in UC patients.

Methods

The serum ghrelin and obestatin levels were measured in 21 UC patients (12 with active disease and 9 in remission) using enzyme-linked immunosorbent assay. The relationship between the circulating levels of these 2 hormones and disease activity was analyzed. The colonic mucosal mRNA expression of ghrelin and obestatin was measured by quantitative reverse transcription polymerase chain reaction.

Results

The mean serum ghrelin values were significantly higher in patients with active disease than in patients with remission (1370.6±404.3 vs. 783.5±235.3 pg/mL, P=0.001). Colonic mucosal mRNA expression of ghrelin was also significantly higher in patients with active disease than in patients in remission (0.805±0.214 vs. 0.481±0.356, P=0.018). However, the mean serum obestatin levels and colonic mucosal mRNA expression of obestatin were not significantly different between both groups. The circulating obestatin/ghrelin ratio was significantly lower in patients with active UC than in patients in remission (0.32±0.08 vs. 0.58±0.20, P=0.001).

Conclusions

The serum ghrelin levels and the obestatin/ghrelin ratio were related to the activity of UC, but serum obestatin was not related to activity of UC. The ghrelin levels and the obestatin/ghrelin ratio could serve as activity markers in patients with UC.

Resistin is associated with breach of tolerance and anti-nuclear antibodies in patients with hepatobiliary inflammation

Resistin is a cysteine-rich protein, which is abundantly expressed at the site of inflammation, and acts as a regulator of the NF-kB-dependent cytokine cascade. The aim of this study was to evaluate resistin levels in relation to inflammatory mediators, disease phenotype and autoantibody status in a spectrum of pathological conditions of the gastrointestinal tract. Resistin levels were measured with an ELISA in sera originated from 227 patients and 40 healthy controls (HC). Fifty patients diagnosed with non-alcoholic fatty liver disease (NAFLD), 53 ulcerative colitis (UC), 51 Crohn's disease (CD), 46 autoimmune hepatitis (AIH) and 27 primary sclerosing cholangitis (PSC) were included. The sera were analysed with respect to biochemical parameters of systemic inflammation and liver function and to the presence of antibodies to nuclear antigens (ANA), mitochondria (AMA) and smooth muscle (SMA). Compared with HC, resistin levels were raised in AIH (P = 0.017) and PSC (P = 0.03); compared with NAFLD, levels were elevated in CD (P = 0.041), AIH (P < 0.001) and PSC (P < 0.001). Patients with elevated levels of resistin were more often treated with corticosteroids, but no difference was found between active disease and clinical remission. Resistin levels were significantly higher in ANA-positive individuals compared with ANA-negative (P = 0.025). Resistin levels were directly correlated with IL-6 (r = 0.30, P = 0.02) and IL-8 (r = 0.51, P < 0.001). Elevated levels of resistin were prominent in patients with hepatobiliary inflammation and were associated with breach of self-tolerance, i.e. ANA positivity. Thus, we propose that resistin may be an important marker of disease severity in autoantibody-mediated gastrointestinal inflammatory diseases.