Urotensin II receptor expression in patients with ulcerative colitis: a pilot study

Expanding Structure-Activity Relationships of Human Urotensin II Peptide Analogues: A Proposed Key Role of the N-Terminal Region for Novel Urotensin II Receptor Modulators

While the urotensinergic system plays a role in influencing various pathologies, its potential remains untapped because of the absence of therapeutically effective urotensin II receptor (UTR) modulators. Herein, we developed analogues of human urotensin II (hU-II) peptide in which, along with well-known antagonist-oriented modifications, the Glu1 residue was subjected to single-point mutations. The generated library was tested by a calcium mobilization assay and ex vivo experiments, also in competition with selected ligands. Interestingly, many derivatives showed noncompetitive modulation that was rationalized by the lateral allostery concept applied to a G protein-coupled receptor (GPCR) multimeric model. UPG-108 showed an unprecedented ability to double the efficacy of hU-II, while UPG-109 and UPG-111 turned out to be negative allosteric modulators of UTR. Overall, our investigation will serve to explore and highlight the expanding possibilities of modulating the UTR system through N-terminally modified hU-II analogues and, furthermore, will aim to elucidate the intricate nature of such a GPCR system.

Diagnostic Procedures for Inflammatory Bowel Disease: Laboratory, Endoscopy, Pathology, Imaging, and Beyond

Diagnosing inflammatory bowel disease (IBD) can often be challenging, and differentiating between Crohn's disease and ulcerative colitis can be particularly difficult. Diagnostic procedures for IBD include laboratory tests, endoscopy, pathological tests, and imaging tests. Serological and stool tests can be easily performed in an outpatient setting and provide critical diagnostic clues. Although endoscopy is an invasive procedure, it offers essential diagnostic information and allows for tissue biopsy and therapeutic procedures. Video capsule endoscopy and device-assisted enteroscopy are endoscopic procedures used to evaluate the small bowel. In addition to endoscopy, magnetic resonance imaging, computed tomography, and ultrasound (US) are valuable tools for small bowel assessment. Among these, US is noninvasive and easily utilized, making its use highly practical in daily clinical practice. Endoscopic biopsy aids in the diagnosis of IBD and is crucial for assessing the histological activity of the disease, facilitating a thorough evaluation of disease remission, and aiding in the development of treatment strategies. Recent advances in artificial intelligence hold promise for enhancing various aspects of IBD management, including diagnosis, monitoring, and precision medicine. This review compiles current procedures and promising future tools for the diagnosis of IBD, providing comprehensive insights.

The urotensin-II receptor: A marker for staging and steroid outcome prediction in ulcerative colitis

BACKGROUND

Urotensin-II receptor- (UTR) related pathway exerts a key-role in promoting inflammation. The aim was to assess the relationship between UTR expression and clinical, endoscopic and biochemical severity of ulcerative colitis (UC), exploring its predictivity of intravenous (iv) steroid administration therapeutic outcome.

METHODS

One-hundred patients with first diagnosis of UC and 44 healthy subjects were enrolled. UTR expression was assessed by qPCR, Western Blot (WB) and immunohistochemistry (IHC). Clinical, endoscopic and histological activity of UC were evaluated by using Truelove and Witts (T&W) severity index, Mayo Endoscopic Score (MES), and Truelove and Richards Index (TRI). The partial and full Mayo scores (PMS and FMS) were assessed to stage the disease.

RESULTS

The UTR expression, resulted higher in the lesioned mucosa of UC patients in comparison to healthy subjects (p < .0001 all). Direct relationship between UTR (mRNA and protein) expression and disease severity assessment (T&W, PMS, MES and TRI) was highlighted (p < .0001 all). UTR expression resulted also higher in the 72 patients requiring iv steroids administration compared to those who underwent alternative medications, (p < .0001). The 32 steroid-non-responders showed an increased UTR expression (WB, IHC and qPCR from lesioned mucosa), compared to 40 steroid-responders (p: .0002, .0001, p < .0001 respectively). The predictive role of UTR expression (p < .05) on the negative iv steroids administration therapeutic outcome was highlighted and ROC curves identified the thresholds expressing the better predictive performance.

CONCLUSIONS

UTR represents a promising inflammatory marker related to clinical, endoscopic, and histological disease activity as well as a predictive marker of steroid administration therapeutic outcome in the UC context.

Urotensin II levels in patients with inflammatory bowel disease

BACKGROUND

Patients with inflammatory bowel disease (IBD) are associated with increased cardiovascular risk and have increased overall cardiovascular burden. On the other hand, urotensin II (UII) is one of the most potent vascular constrictors with immunomodulatory effect that is connected with a number of different cardiometabolic disorders as well. Furthermore, patients with ulcerative colitis have shown increased expression of urotensin II receptor in comparison to healthy controls. Since the features of IBD includes chronic inflammation and endothelial dysfunction as well, it is plausible to assume that there is connection between increased cardiac risk in IBD and UII.

AIM

To determine serum UII levels in patients with IBD and to compare them to control subjects, as well as investigate possible associations with relevant clinical and biochemical parameters.

METHODS

This cross sectional study consecutively enrolled 50 adult IBD patients (26 with Crohn’s disease and 24 with ulcerative colitis) and 50 age and gender matched controls. Clinical assessment was performed by the same experienced gastroenterologist according to the latest guidelines. Ulcerative Colitis Endoscopic Index of Severity and Simple Endoscopic Score for Crohn’s Disease were used for endoscopic evaluation. Serum levels of UII were determined using the enzyme immunoassay kit for human UII, according to the manufacturer’s instructions.

RESULTS

IBD patients have significantly higher concentrations of UII when compared to control subjects (7.57 ± 1.41 vs 1.98 ± 0.69 ng/mL, P < 0.001), while there were no significant differences between Crohn’s disease and ulcerative colitis patients (7.49 ± 1.42 vs 7.65 ± 1.41 ng/mL, P = 0.689). There was a significant positive correlation between serum UII levels and high sensitivity C reactive peptide levels (r = 0.491, P < 0.001) and a significant negative correlation between serum UII levels and total proteins (r = -0.306, P = 0.032). Additionally, there was a significant positive correlation between serum UII levels with both systolic (r = 0.387, P = 0.005) and diastolic (r = 0.352, P = 0.012) blood pressure. Moreover, serum UII levels had a significant positive correlation with Ulcerative Colitis Endoscopic Index of Severity (r = 0.425, P = 0.048) and Simple Endoscopic Score for Crohn’s Disease (r = 0.466, P = 0.028) scores. Multiple linear regression analysis showed that serum UII levels retained significant association with high sensitivity C reactive peptide (β ± standard error, 0.262 ± 0.076, P < 0.001) and systolic blood pressure (0.040 ± 0.017, P = 0.030).

CONCLUSION

It is possible that UII is involved in the complex pathophysiology of cardiovascular complications in IBD patients, and its purpose should be investigated in further studies.