Colon targeted bioadhesive pellets of curcumin and cyclosporine for improved management of inflammatory bowel disease

Formulation and optimization of a single-layer coat for targeting budesonide pellets to the descending Colon

The current budesonide formulations are inadequate for addressing left-sided colitis, and patients might hesitate to use an enema for a prolonged time. This study focuses on developing a single-layer coating for budesonide pellets targeting the descending colon. Pellets containing budesonide (1.5%w/w), PVP K30 (5%w/w), lactose monohydrate (25%w/w) and Avicel pH 102 (68.5%w/w) were prepared using extrusion spheronization technique. Coating formulations were designed using response surface methodology with pH and time-dependent Eudragits. Dissolution tests were conducted at different pH levels (1.2, 6.5, 6.8, and 7.2). Optimal coating formulation, considering coating level and the Eudragit (S + L) ratio to the total coating weight, was determined. Budesonide pellets were coated with the optimized composition and subjected to continuous dissolution testing simulating the gastrointestinal tract. The coating, with 48% S, 12% L, and 40% RS at a 10% coating level, demonstrated superior budesonide delivery to the descending colon. Coated pellets had a spherical shape with a uniform 30 µm thickness coating, exhibiting pH and time-dependent release. Notably, zero-order release kinetics was observed for the last 9 h in colonic conditions. The study suggests that an optimized single-layer coating, incorporating pH and time-dependent polymers, holds promise for consistently delivering budesonide to the descending colon.

Multifunctional nanoparticle-mediated combining therapy for human diseases

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and treatment. In preclinical investigations, combined effect of certain known drugs has been well established in treating extensive human diseases. Attributed to synergistic effects by targeting various disease pathways and advantages, such as reduced administration dose, decreased toxicity, and alleviated drug resistance, combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses, such as cancer, atherosclerosis, pulmonary hypertension, myocarditis, rheumatoid arthritis, inflammatory bowel disease, metabolic disorders and neurodegenerative diseases. Combinatorial therapy involves combining or co-delivering two or more drugs for treating a specific disease. Nanoparticle (NP)-mediated drug delivery systems, i.e., liposomal NPs, polymeric NPs and nanocrystals, are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery, extended drug release, and higher drug stability to avoid rapid clearance at infected areas. This review summarizes various targets of diseases, preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical diseases. Ultimately, we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the limitations. This review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

Aerogels as Carriers for Oral Administration of Drugs: An Approach towards Colonic Delivery

Polysaccharide aerogels have emerged as a highly promising technology in the field of oral drug delivery. These nanoporous, ultralight materials, derived from natural polysaccharides such as cellulose, starch, or chitin, have significant potential in colonic drug delivery due to their unique properties. The particular degradability of polysaccharide-based materials by the colonic microbiota makes them attractive to produce systems to load, protect, and release drugs in a controlled manner, with the capability to precisely target the colon. This would allow the local treatment of gastrointestinal pathologies such as colon cancer or inflammatory bowel diseases. Despite their great potential, these applications of polysaccharide aerogels have not been widely explored. This review aims to consolidate the available knowledge on the use of polysaccharides for oral drug delivery and their performance, the production methods for polysaccharide-based aerogels, the drug loading possibilities, and the capacity of these nanostructured systems to target colonic regions.

Biochemical and histopathological evidence for beneficial effects of Empagliflozin pretreatment on acetic acid-induced colitis in rats

BACKGROUND

Ulcerative Colitis (UC) is a disorder which oxidative stress plays a critical role in its pathogenesis. Empagliflozin (EMPA) is a sodium-glucose cotransporter-2 (SGLT2) inhibitor that has been shown to have anti-inflammatory and antioxidative effects. The aim of this study was to investigate the protective effects of EMPA on acetic acid (AA) induced colitis in rats.

METHODS

A total of twenty-four rats were divided into four groups (six animals in each group) as follows: (1) Control group; (2) acetic acid (AA)-induced colitis group (AA); (3) EMPA treatment group (AA + EMPA); (4) Dexamethasone (Dexa) treatment group (AA + Dexa). Animals in pre-treatment groups received EMPA (10 mg/kg, i.p.) or dexamethasone (4 mg/kg, i.p. as reference drug) for four consecutive days before induction of colitis by intra-rectal acetic acid (4% v/v) administration. Twenty-four hours after AA administration, rats were sacrificed and the colon tissues were removed for histopathological and biochemical evaluations.

RESULTS

Pretreatment with EMPA significantly decreased colon weight/length ratio (81.00 ± 5.28 mg/cm vs. 108.80 ± 5.51 mg/cm) as well as, macroscopic (2.50 ± 0.57 vs. 3.75 ± 0.25) and histological scores (3.3 ± 0.14 vs. 1.98 ± 0.14) compared to the AA-induced colitis group (p < 0.01). Pretreatment with EMPA significantly reduced malondialdehyde (MDA) (324.0 ± 15.93 vs. 476.7 ± 32.26 nmol/mg p < 0.001) and increased glutathione level (117.5 ± 4.48 vs. 94.38 ± 3.950 µmol/mg, p < 0.01) in comparison to the AA-induced colitis group. Furthermore, a significant increase in catalase (44.60 ± 4.02 vs.14.59 ± 2.03 U/mg, P < 0.01), superoxide dismutase (283.9 ± 18.11 vs. 156.4 ± 7.92 U/mg, p < 0.001), and glutathione peroxidase (10.38 ± 1.45 vs. 2.508 ± 0.37, p < 0.01) activities were observed by EMPA pretreatment when compared to the AA-induced colitis group. These results were in line with those of the reference drug.

CONCLUSIONS

It is concluded that EMPA could effectively reduce the severity of tissue injury in experimental colitis. This protective effect may be related to the antioxidative effects of EMPA drug.

Topotecan alleviates acetic acid-induced ulcerative colitis in rats via attenuation of the RORγT transcription factor

AIMS

Ulcerative colitis is characterized as a chronic immune-mediated inflammatory condition, affecting the intestinal gastroenteric tissue. Previous studies revealed that Th-17 cells are key players in the pathogenesis of ulcerative colitis. RORγT (Retinoic-acid-receptor-related orphan receptor-gamma T) is a lineage-specific transcription factor of Th-17 cells and thus has a role in their differentiation. Transient inhibition of RORγT has been reported to attenuate the differentiation of Th-17 cells and secretion of interleukin-17 (IL-17). Here, we investigated the efficacy of topotecan in ameliorating ulcerative colitis in rodents, via inhibition of the RORγT transcription factor.

MAIN METHODS AND KEY FINDINGS

Experimental ulcerative colitis was induced in rats by intrarectal acetic acid administration. Topotecan attenuated the severity of ulcerative colitis in rats by revoking neutrophils and macrophage infiltration to the colon. It also alleviated diarrhea and rectal bleeding and improved body weight. Further, attenuation of RORγT and IL-17 expression was observed in topotecan treated animals. Levels of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β in the colon tissue were reduced by topotecan treatment. Significant reduction in malondialdehyde level, elevation of superoxide dismutase (SOD) and catalase activity was observed in the colon tissue of rats treated with topotecan compared to the diseased group.

SIGNIFICANCE

This study shows the therapeutic potential of topotecan in attenuating ulcerative colitis in rats probably via inhibition of the RORγT transcription factor and downstream mediators of Th-17 cells.

Comparison of 5-ASA layered or matrix pellets coated with a combination of ethylcellulose and Eudragits L and S in the treatment of ulcerative colitis in rats

The aim of this study was to evaluate and optimize the combination of time and pH-dependent polymers as a single coating for the design of the colon-specific drug delivery system of 5-aminosalicylic acid (5-ASA) pellets. 5-ASA matrix pellets with a 70% drug load were prepared by the extrusion-spheronization method. The optimal coating formula which included Eudragit S (ES)+Eudragit L (EL)+Ethylcellulose (EC) was predicted for the targeted drug delivery to the colonic area by a 3² factorial design. The ratio of ES:EL:EC and coating level were considered as independent variables while the responses were the release of less than 10% of the drug within 2 h (Y₁), the release of 60-70% within 10 h at pH 6.8 (Y₂) and lag time of less than 1 h at pH 7.2 (Y₃). Also, 5-ASA layered pellets were prepared by the powder layering of 5-ASA on nonpareils (0.4-0.6 mm) in a fluidized bed coater and then coated with the same optimum coating composition. The coated 5-ASA layered or matrix pellets were tested in a rat model of ulcerative colitis (UC) and compared with the commercial form of 5-ASA pellets (Pentasa®). The ratio of ES:EL:EC of 33:52:15 w/w at a coating level of 7% was discovered as the optimum coating for the delivery of 5-ASA matrix pellets to the colon. The coated 5-ASA pellets were spherical with uniform coating as shown by SEM and met all of our release criteria as predicted. In-vivo studies demonstrated that the optimum 5-ASA layered or matrix pellets had superior anti-inflammatory activities than Pentasa® in terms of colitis activity index (CAI), colon damage score (CDS), colon/body weight ratio and colon's tissue enzymes of glutathione (GSH) and malondialdehyde (MDA). The optimum coating formulation showed a high potential for colonic delivery of 5-ASA layered or matrix pellets and triggered drug release based on pH and time.

Development of Novel pH-Sensitive Eudragit Coated Beads Containing Curcumin-Mesalamine Combination for Colon-Specific Drug Delivery

This research aims to develop a drug delivery system that effectively treats colitis while administering curcumin/mesalamine by coating alginate/chitosan beads with Eudragit® S-100 to target the colon. Beads were tested to determine their physicochemical characteristics. Coating with Eudragit® S-100 prevents drug release at a pH of less than 7; this was demonstrated by in-vitro release conducted in a medium with gradually varying pH to mimic circumstances in various regions of the gastrointestinal tract. This study examined the efficacy of the coated beads in treating acetic acid-induced colitis in rats. Results showed that spherical beads were formed with an average diameter of 1.6–2.8 mm, and the obtained swelling ranged from 409.80% to 890.19%. The calculated entrapment efficiency ranged from 87.49% to 97.89%. The optimized formula F13 (which was composed of mesalamine-curcumin active ingredients, Sodium alginate as a gelling agent, chitosan as a controlled release agent, CaCl2 as a crosslinking agent, and Eudragit S-100 as a pH-sensitive coating agent) demonstrated the best entrapment efficiency (97.89% ± 1.66), swelling (890.19% ± 60.1), and bead size (2.7 ± 0.62 mm). In formulation #13, which was coated with Eudragit S 100, curcumin (6.01 ± 0.04%) and mesalamine (8.64 ± 0.7%), were released after 2 h at pH 1.2; 6.36 ± 0.11% and 10.45 ± 1.52% of curcumin and mesalamine, respectively, were then released after 4 h and at pH 6.8. Meanwhile, at pH 7.4, after 24 h, approximately 85.34 ± 2.3% (curcumin) and 91.5 ± 1.2% (mesalamine) were released. Formula #13 significantly reduced the colitis, and this suggests that the developed hydrogel beads can be used for delivering curcumin-mesalamine combinations to treat ulcerative colitis after adequate research.

A review on curcumin colon-targeted oral drug delivery systems for the treatment of inflammatory bowel disease

Synthetic drugs and monoclonal antibodies are the typical treatments to combat inflammatory bowel disease (IBD). However, side effects are present when these treatments are used, and their continued application could be restricted by the high relapse rate of the disease. One potential alternative to these treatments is the use of plant-derived products. The use curcumin is one such treatment option that has seen an increase in usage in treating IBD. Curcumin is derived from a rhizome of turmeric (Curcuma longa), and the results of studies on the use of curcumin to treat IBD are promising. These studies suggest that curcumin interacts with cellular targets such as NF-κB, JAKs/STATs, MAPKs, TNF-α, IL-6, PPAR, and TRPV1 and may reduce the progression of IBD. Potentially, curcumin can be used as a therapeutic agent for patients with IBD when it reduces the incidence of clinical relapse. This review discusses the strategies utilized in designing and developing an oral colonic delivery dosage form of curcumin.

Formulation development and in-vitro/ex-vivo evaluation for a polysaccharide-based colon targeted matrix tablet

OBJECTIVE

The objective of this study was to develop and optimize a microflora-triggered colon targeted sustained-release dosage form using gum ghatti (GG) and hydroxypropyl methylcellulose (HPMC K100).

METHODS

GG and HPMC K100 were used to prepare microflora triggered colon targeted sustained-release dosage form. For evaluation, two different tablets comprising metoprolol succinate and mesalamine as an active ingredient were used with the objective of developing a platform technology for various categories of drugs. The tablets were coated with Eudragit® L100 and Eudragit® S100 to provide enteric coating and evaluated for hardness, thickness, friability, weight variation, disintegration, and drug content. In vitro release studies for the prepared tablets were carried out mimicking the physiological transit time. Further, the effects of microflora were evaluated using rat cecal content.

RESULTS

The in vitro dissolution profile of coated matrix tablets showed that 86.03±0.43% of metoprolol succinate and 80.26±0.67% of mesalamine were released at the end of 12 h. The ex vivo dissolution profile of coated matrix tablets showed that 96.50±0.27% of metoprolol succinate and 92.58±0.39% of mesalamine were released at the end of 12 h in the presence of rat ceacal content. The developed formulation was stable when subjected to the standard ICH stability study conditions.

CONCLUSION

The result of this study showed that gum ghatti together with hydroxypropyl methylcellulose could be successfully used for the preparation of microflora triggered colon targeted matrix tablets.

Curcumin and Its Modified Formulations on Inflammatory Bowel Disease (IBD): The Story So Far and Future Outlook

Inflammatory bowel disease (IBD) is a chronic relapsing and remitting inflammatory disorder of the small intestine and colon. IBD includes ulcerative colitis (UC) and Crohn's disease (CD), and it is a major factor for the development of colon cancer, referred to as colitis-associated cancer (CAC). The current treatment of IBD mainly includes the use of synthetic drugs and monoclonal antibodies. However, these drugs have side effects over long-term use, and the high relapse rate restricts their application. In the recent past, many studies had witnessed a surge in applying plant-derived products to manage various diseases, including IBD. Curcumin is a bioactive component derived from a rhizome of turmeric (Curcuma longa). Numerous in vitro and in vivo studies show that curcumin may interact with many cellular targets (NF-κB, JAKs/STATs, MAPKs, TNF-γ, IL-6, PPARγ, and TRPV1) and effectively reduce the progression of IBD with promising results. Thus, curcumin is a potential therapeutic agent for patients with IBD once it significantly decreases clinical relapse in patients with quiescent IBD. This review aims to summarize recent advances and provide a comprehensive picture of curcumin's effectiveness in IBD and offer our view on future research on curcumin in IBD treatment.

Effects of the Use of Curcumin on Ulcerative Colitis and Crohn's Disease: A Systematic Review

Inflammatory bowel disease (IBD) is an umbrella term used to describe chronic inflammatory disorders related to a substantial reduction in the quality of life of patients. Some patients with Crohn's disease (CD) and ulcerative colitis (UC) are refractory to conventional therapies, and Curcuma longa derivatives have been considered as adjuvants. Owing to the anti-inflammatory and antioxidant effects, some clinical trials used this plant in the therapeutic approach of IBD, and some meta-analyses evaluated the outcomes found in these studies. Owing to controversial findings, our systematic review aimed to evaluate these studies to show whether C. longa compounds can still be considered in the therapeutic approach of patients with CD and UC. MEDLINE-PubMed, EMBASE, and Cochrane were searched, and Preferred Reporting Items for a Systematic Review and Meta-Analysis guidelines were followed. The results of the randomized clinical trials (RCTs) showed promising results with the use of curcumin in the therapeutic approach of both UC and CD patients. Some meta-analyses show controversial results, possibly due to the presence of bias in the included studies. The actions of curcumin are achieved by several mechanisms, such as reducing the expression of interleukin (IL)-1, IL-6, IL-12, and tumor necrosis factor-α. Moreover, it reduces the levels of reactive oxygen species, such as superoxide anions and malondialdehyde. The results of using curcumin in CD and UC patients are challenging to be evaluated because RCTs are variable in the dose and the formulations of curcumin, in the time of treatment, and the route of administration. The number of patients in the samples is also usually small.