Oral liposomal delivery of an activatable budesonide prodrug reduces colitis in experimental mice

An overview on recent approaches for colonic drug delivery systems

Colon-targeted drug delivery systems have garnered significant interest as potential solutions for delivering various medications susceptible to acidic and catalytic degradation in the gastrointestinal (GI) tract or as a means of treating colonic diseases naturally with fewer overall side effects. The increasing demand for patient-friendly drug administration underscores the importance of colonic drug delivery, particularly through noninvasive methods like nanoparticulate drug delivery technologies. Such systems offer improved patient compliance, cost reduction, and therapeutic advantages. This study places particular emphasis on formulations and discusses recent advancements in various methods for designing colon-targeted drug delivery systems and their medicinal applications.

Bilosomes and Biloparticles for the Delivery of Lipophilic Drugs: A Preliminary Study

In this study, bile acid-based vesicles and nanoparticles (i.e., bilosomes and biloparticles) are studied to improve the water solubility of lipophilic drugs. Ursodeoxycholic acid, sodium cholate, sodium taurocholate and budesonide were used as bile acids and model drugs, respectively. Bilosomes and biloparticles were prepared following standard protocols with minor changes, after a preformulation study. The obtained systems showed good encapsulation efficiency and dimensional stability. Particularly, for biloparticles, the increase in encapsulation efficiency followed the order ursodeoxycholic acid < sodium cholate < sodium taurocholate. The in vitro release of budesonide from both bilosytems was performed by means of dialysis using either a nylon membrane or a portion of Wistar rat small intestine and two receiving solutions (i.e., simulated gastric and intestinal fluids). Both in gastric and intestinal fluid, budesonide was released from bilosystems more slowly than the reference solution, while biloparticles showed a significant improvement in the passage of budesonide into aqueous solution. Immunofluorescence experiments indicated that ursodeoxycholic acid bilosomes containing budesonide are effective in reducing the inflammatory response induced by glucose oxidase stimuli and counteract ox-inflammatory damage within intestinal cells.

Minocycline synergizes with corticosteroids in reducing colitis severity in mice via the modulation of pro-inflammatory molecules

Background: A few studies have highlighted the anti-inflammatory properties of minocycline in reducing colitis severity in mice, but its molecular mechanism is not fully understood. The aim of this study was to determine the anti-inflammatory properties of minocycline and the expression/activity profiles of molecules involved in pro-inflammatory signaling cascades, cytokines, and molecules involved in the apoptotic machinery. The synergistic effect between minocycline and corticosteroids was also evaluated. Methods: The effects of various treatment approaches were determined in mice using the dextran sulfate sodium (DSS) colitis model at gross and microscopic levels. The expression/activity profiles of various pro- or anti-inflammatory molecules were determined using Western blotting and polymerase chain reaction (PCR). Results: Minocycline treatment significantly reduced colitis severity using prophylactic and treatment approaches and produced a synergistic effect with budesonide and methylprednisolone in reducing the active state of colitis. This was mediated in part through reduced colonic expression/activity of pro-inflammatory molecules, cytokines, proteins involved in the apoptotic machinery, and increased expression of the anti-inflammatory cytokine IL-10. Conclusion: Minocycline synergizes with corticosteroids to reduce colitis severity, which could reduce their dose-dependent side effects and treatment cost. The reduction in colitis severity was achieved by modulating the expression/activity profiles of various pro- and anti-inflammatory signaling molecules, cytokines, and molecules involved in the apoptotic machinery.

Colon-Adhering Delivery System with Inflammation Responsiveness for Localized Therapy of Experimental Colitis

Ulcerative colitis (UC) is a chronic inflammation-related disease that severely affects the colon and rectum regions. A variety of therapy regimens are used for the treatment of UC. Clinically, therapeutic enema is the choice of therapy for UC patients. Irrespective of on-site administration, the major limitation of therapeutic enemas is the dispossession of the medicine followed by low drug availability for the therapeutic action. In our present work, we have developed an enzyme-responsive injectable hydrogel (ER-hydrogel) to overcome the limitations of therapeutic enema. The hydrogels possess two major advantages, which are being exploited for therapeutic drug delivery in UC: prolonged retention and enzyme responsiveness. The former is one of the prominent advantages of hydrogel compared to free drug enema and the latter controls the release of the drug or provides drug release on-demand. The ER-hydrogel was formulated by the heat-cool method and for therapeutic purposes, a corticosteroid drug, budesonide (Bud), was encapsulated into the ER-hydrogel and evaluated for its various physicochemical and therapeutic potentials in dextran sodium sulfate (DSS)-induced UC. In vitro and ex vivo adhesion studies confirm the retention or mucoadhesive nature of the ER-hydrogel, and the upsurge in Bud release from the Bud-loaded ER-hydrogel upon the addition of esterase enzyme confirms the enzyme-mediated drug release from the ER-hydrogel. Moreover, Bud-loaded ER-hydrogel exhibited promising results in alleviating the disease activity index of UC, and restored the length of the colon, which is the main hallmark of UC. In terms of the health of the colon tissue, the Bud-loaded ER-hydrogel restored the colonic tissue damage, as seen in the H&E-stained, AB-NR-stained, and HID-AB-stained colon sections. Finally, the Bud-loaded ER-hydrogel also markedly subsided the IL-1β, TNF-α, MPO, and nitrite levels in serum and colon tissues. Thus, the fabricated Bud-loaded ER-hydrogel possesses appreciable translational potential due to its ability to significantly ameliorate inflammatory changes compared to naive or water-based therapeutic enema in acute experimental colitis in mice.