Introduction

Crohn’s disease (CD) is characterized by chronic uncontrolled inflammation which often leads to intestinal fibrosis. Up to 70% of patients with CD will develop strictures and will undergo surgery as the only available therapeutic option. However, the pathogenesis of CD fibrosis remains incompletely understood. Studies are mainly focused on mesenchymal cells, cytokines and growth factors, whereas the role of neutrophils remains elusive.^1–5 Previous data by our group indicated that neutrophils may acquire a pre-fibrotic role by inducing the differentiation and activation of fibroblasts.^6,7

Aims & Methods

This study aims to investigate for the first time the role of neutrophil-intestinal fibroblast interplay in the pathogenesis of CD immunofibrosis suggesting possible targets for therapeutic interventions.
Neutrophils and intestinal biopsies were obtained from treatment naive patients with moderate to severe CD (CDAI ≥220) and UC (Mayo DAI ≥6). Additionally, sex- and age-matched healthy individuals (HI), were served as controls. Intestinal tissues were characterized using immunohistochemistry and immunofluorescence. Primary intestinal fibroblasts (PIFbs) isolated from tissue specimens were also studied using real-time qPCR, confocal immunofluorescence imaging, in-cell ELISA (cytoblot) and collagen assay. Various inflammatory mediators were measured in cell cultures supernatants with ELISA and multiplex bead-based flow cytometry. The migratory capacity of neutrophils was assessed by a chemotaxis cell migration fluorometric assay.

Results

PIFbs from patients with CD, compared to UC and HI, exhibited a fibrotic phenotype that was characterized by low Krüppel-like Factor 2 (KLF2) and increased Cellular Communications Network Factor 2 (CCN2) mRNA and protein expression leading to excessive collagen production. Neutrophil-fibroblast co-existence was obvious in intestinal tissue fibrotic lesions of CD patients. In line with this, PIFbs culture supernatants from CD patients yielded high levels of IL-8 and increased chemotactic activity for HI neutrophils, which was reduced significantly upon IL-8 neutralization. Of note, compared to UC, neutrophil culture extracts from CD patients downregulated KLF2 and induced CCN2 expression in HI PIFbs acquiring a CD pre-fibrotic phenotype. This neutrophil-mediated immunofibrotic effect was abolished in-vitro by pharmaceutical inhibition of JAK/STAT signaling in PIFbs.

Conclusion

These results, provide a novel mechanistic basis for immunofibrosis in CD suggesting neutrophil/JAK/STAT/fibroblast/IL-8 molecular pathway as a candidate therapeutic target.

References

1. Zidar N, Langner C, Jerala M, Boštjančič E, Drobne D, Tomažič A. Pathology of Fibrosis in Crohn’s Disease—Contribution to Understanding Its Pathogenesis. Front Med (Lausanne). 2020;7:167. doi:10.3389/fmed.2020.00167
2. Santacroce G, Lenti MV, Di Sabatino A. Therapeutic Targeting of Intestinal Fibrosis in Crohn’s Disease. Cells. 2022;11(3):429. doi:10.3390/cells11030429
3. Wéra O, Lancellotti P, Oury C. The Dual Role of Neutrophils in Inflammatory Bowel Diseases. J Clin Med. 2016;5(12):118. doi:10.3390/jcm5120118
4. Lipson KE, Wong C, Teng Y, Spong S. CTGF is a central mediator of tissue remodeling and fibrosis and its inhibition can reverse the process of fibrosis. Fibrogenesis Tissue Repair. 2012;5(Suppl 1):S24. doi:10.1186/1755-1536-5-S1-S24
5. Salas A, Hernandez-Rocha C, Duijvestein M, et al. JAK-STAT pathway targeting for the treatment of inflammatory bowel disease. Nat Rev Gastroenterol Hepatol. 2020;17(6):323-337. doi:10.1038/s41575-020-0273-0
6. Chrysanthopoulou A, Mitroulis I, Apostolidou E, et al. Neutrophil extracellular traps promote differentiation and function of fibroblasts. The Journal of Pathology. 2014;233(3):294-307. doi:10.1002/path.4359
7. Chrysanthopoulou A, Antoniadou C, Natsi AM, et al. Down-regulation of KLF2 in lung fibroblasts is linked with COVID-19 immunofibrosis and restored by combined inhibition of NETs, JAK-1/2 and IL-6 signaling. Clin Immunol. 2023;247:109240. doi:10.1016/j.clim.2023.109240

Disclosure

This study was supported by the Greek General Secretariat for Research and Technology (GSRT), Research & Innovation Programme CytoNET, grant MIS-5048548 and by GSRT, Regional Excellence Programme InTechThrace, grant MIS-5047285.

Introduction

Capsule colonoscopy and Pan-intestinal Capsule Endoscopy (PCE) are well-established diagnostic procedures. However, the optimal bowel preparation regimen remains undefined, with pooled adequate cleansing rates reaching only 72.5%¹. While ultra-low volume preparations (≤1L) have demonstrated efficacy in conventional colonoscopy², their effectiveness in capsule-based modalities has yet to be determined.

Aims & Methods

In this prospective, randomized, researcher-blind, single center trial, we compared the efficacy of two ultra-low volume bowel preparation regimens, 1L Polyethylene Glycol Plus Ascorbic Acid (PEG-Asc) and 1L Sodium Picossulfate with Magnesium Citrate (SPMC). Patients referred for capsule-based procedures were randomized in a 1:1 ratio to receive either PEG-Asc or SPMC. The primary endpoints were the rates of complete examinations, adequate bowel preparation, and excellent right colon cleansing.

Results

A total of 117 patients were included, referred for capsule colonoscopy due to incomplete colonoscopy (76.1%) or for PCE to assess luminal inflammation (17.9%) or anemia (6%). Overall, 61.5% were female, with a mean age of 61.3 ± 16 years. The complete examination rate was 71.8%, with no significant difference between groups (PEG-Asc 72.9% vs. SPMC 70.7%; p = 0.792). Adequate bowel preparation was achieved in 62.4% of cases, which was significantly more frequent in the PEG-Asc group (72.9%) compared to SPMC (51.7%; p = 0.018). Among complete procedures, excellent right colon cleansing was observed more often with PEG-Asc (34.1%) than with SPMC (7.3%; p = 0.003).

Conclusion

The completion and adequate preparation rates remain suboptimal in the capsule colonoscopy and PCE procedures. In this study, both ultra-low volume purgative solutions demonstrated comparable efficacy in achieving complete examinations, but the PEG-Asc resulted in significantly better overall preparation quality and superior right colon cleansing compared to SPMC. These findings suggest that PEG-Asc may be the preferred ultra-low volume regimen for optimizing bowel visualization in capsule-based examinations.

References

1. Rosa, B., Donato, H., Cúrdia Gonçalves, T., Sousa-Pinto, B. & Cotter, J. What Is the Optimal Bowel Preparation for Capsule Colonoscopy and Pan-intestinal Capsule Endoscopy? A Systematic Review and Meta-Analysis. Dig. Dis. Sci. 68, 4418–4431 (2023).
2. Arieira, C. et al. Bowel cleansing efficacy for colonoscopy: prospective, randomized comparative study of same-day dosing with 1-L and 2-L PEG + ascorbate. Endosc. Int. Open 09, E1602–E1610 (2021).

Introduction

Sodium picosulfate (SP)/magnesium citrate (MC) and polyethylene glycol (PEG) plus ascorbic acid are recommended by Western guidelines as laxative solutions for bowel preparation. The standard formulation for bowel preparation is PEG; however, it requires a large dose and has a distinctive taste that is considered unpleasant. SP/MC requires a small dose and ensures fluid intake because it is administered in another beverage. Therefore, clinical studies have shown that SP/MC is superior to PEG in terms of acceptability.

Aims & Methods

Our aim was to compare the novel bowel cleansing method (test group) consisting of SP/MC with elobixibat hydrate and the standard bowel cleansing method consisting of PEG plus ascorbic acid (standard group) in patients preparing for outpatient colonoscopy. This was a multicenter, single-blind, non-inferiority, randomized controlled trial. Patients 40-69 years of age scheduled for outpatient colonoscopy were enrolled. Patients with a history of abdominal or pelvic surgery, constipation, inflammatory bowel disease, or severe organ dysfunction were excluded. The target number of study participants was 540 (standard group, 270 cases; test group, 270 cases). The primary endpoint was bowel cleansing (Boston Bowel Preparation Scale [BBPS] score ≥6). Secondary endpoints were patient acceptability, adverse events, polyp/adenoma detection rate, number of polyps/adenomas detected, degree of bowel cleansing according to BBPS (BBPS score ≥8), degree of bowel cleansing according to Aronchik scale, and bowel cleansing time. The non-inferiority margin for the primary endpoint was 10%. A study protocol of the present study has already been published in a peer-reviewed journal.

Results

Of 540 participants enrolled, efficacy was analyzed in 524 participants (test group, n=263; standard group, n=261) in the full analysis set. Non-inferiority of the test group was demonstrated for the primary endpoint (BBPS ≥6): 96.2% vs. 97.7% for test and standard group, respectively difference was -1.5%, [95%confidence interval (CI), -4.8 to 1.6%] with P<0.001 for non-inferiority. For the secondary endpoint BBPS≥8 was lower in test group (79.5% vs 91.2%: difference -11.7% [95% CI, -17.8 to -5.8%]). Patient acceptability was superior in the test group in the key questions (1. Was the bowel preparation medication easy to use? 2. Were all bowel preparation medications administered internally? 3. What is your overall impression of the bowel preparation? 4. How did the bowel preparation medicine taste? 5. Would you like to use the same bowel preparation medicine for your next colonoscopy?) Adverse events were similar in both groups.

Conclusion

A new regimen of elobixibat plus sodium picosulfate with magnesium citrate was non-inferior in bowel cleansing and superior in patient’s acceptability compared to split-dose 2-L polyethylene glycol with ascorbic acid.

References

1) Hotta K, Otake Y, Yamaguchi D, et al. Comparison of the efficacy and tolerability of elobixibat plus sodium picosulfate with magnesium citrate and split‑dose 2‑L polyethylene glycol with ascorbic acid for bowel preparation before outpatient colonoscopy: a study protocol for the multicentre, randomised, controlled E‑PLUS trial. BMC Gastroenterol 2024 Feb 3;24(1):61.doi: 10.1186/s12876-024-03146-6.

Disclosure

The primary investigator (Kinichi Hotta) had received research funding from Nippon Chemiphar Co. Ltd.