Intrarectal Administration of Adelmidrol plus Hyaluronic Acid Gel Ameliorates Experimental Colitis in Mice and Inhibits Pro-Inflammatory Response in Ex Vivo Cultured Biopsies Derived from Ulcerative Colitis-Affected Patients

Improving clinical outcomes and delaying disease recrudescence in Ulcerative Colitis (UC) patients is crucial for clinicians. In addition to traditional and new pharmacological therapies that utilize biological drugs, the development of medical devices that can ameliorate UC and facilitate the remission phase should not be overlooked. Drug-based therapy requires time to be personalized and to evaluate the benefit/risk ratio. However, the increasing number of diagnosed UC cases worldwide necessitates the exploration of new strategies to enhance clinical outcomes. By incorporating medical devices alongside pharmacological treatments, clinicians can provide additional support to UC patients, potentially improving their condition and slowing down the recurrence of symptoms. Chemically identified as an azelaic acid derivative and palmitoylethanolamide (PEA) analog, adelmidrol is a potent anti-inflammatory and antioxidant compound. In this study, we aimed to evaluate the effect of an intrarectal administration of 2% adelmidrol (Ade) and 0.1% hyaluronic acid (HA) gel formulation in both the acute and resolution phase of a mouse model of colitis induced via DNBS enema. We also investigated its activity in cultured human colon biopsies isolated from UC patients in the remission phase at follow-up when exposed in vitro to a cytomix challenge. Simultaneously, with its capacity to effectively alleviate chronic painful inflammatory cystitis when administered intravesically to urological patients such as Vessilen, the intrarectal administration of Ade/HA gel has shown remarkable potential in improving the course of colitis. This treatment approach has demonstrated a reduction in the histological damage score and an increase in the expression of ZO-1 and occludin tight junctions in both in vivo studies and human specimens. By acting independently on endogenous PEA levels and without any noticeable systemic absorption, the effectiveness of Ade/HA gel is reliant on a local antioxidant mechanism that functions as a “barrier effect” in the inflamed gut. Building on the findings of this preliminary study, we are confident that the Ade/HA gel medical device holds promise as a valuable adjunct in supporting traditional anti-UC therapies.