Meriem Aziez

Background: Kinkeliba (Combretum micranthum G. Don), commonly used in West African traditional pharmacopeia for its anti-inflammatory and gastrointestinal properties, remains poorly studied regarding its potential role in the prevention or treatment of ulcerative colitis. Objective: This study evaluated the therapeutic potential of the ethanolic extract of Combretum micranthum (EECM) in a murine model of chronic DSS-induced colitis. Methods: Male C57BL/6 mice were subjected to three cycles of 1.5% DSS administration over nine weeks to induce chronic colitis. EECM was administered orally at 50, 100, or 200 mg/kg during the final week. Disease severity was evaluated using the Disease Activity Index (DAI), colon length, biochemical and hematological markers, along with histopathological and immunohistochemical assessment of colonic tissue. Results: EECM treatment significantly improved clinical parameters and prevented colon shortening in chronic DSS-induced colitis. These improvements were associated with the restoration of serum biochemical and hematological profiles, along with reduced histopathological damage and preservation of colonic tissue architecture. Immunohistochemical analysis further demonstrated decreased CD3-positive T-lymphocyte infiltration in colonic tissue, suggesting modulation of local immune cell responses. Conclusions: These findings highlight the therapeutic potential EECM in ulcerative colitis and support further investigations to elucidate its mechanisms of action and evaluate its efficacy in future translational studies.

Inflammatory bowel diseases (IBDs), including Crohn’s disease and ulcerative colitis, are chronic inflammatory disorders of the gastrointestinal tract, and current therapies are limited by adverse side effects. Combretum micranthum G. Don (kinkeliba), a medicinal plant traditionally used in West Africa, has been reported to possess pharmacological activities and a favorable safety profile. In this study, an ethanolic extract of Combretum micranthum (EECM) was characterized using HPLC-DAD-ESI-MS to identify its phenolic constituents. Acute colitis was induced in C57BL/6 mice using 3% DSS, while EECM (100 and 200 mg/kg) was administered orally for seven days. Disease Activity Index was monitored daily, and colonic injuries were evaluated through macroscopic and histological analyses, as well as hematological and biochemical assessments. In vitro, EECM contained 293.54 mg/g of total phenolic compounds and showed strong antioxidant activity in DPPH, ABTS, and FRAP assays. Furthermore, the extract exhibited antibacterial activity against Bacillus subtilis, Staphylococcus aureus, Salmonella enterica, and Streptococcus pyogenes at various concentrations. In contrast, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa were not affected at the tested concentrations. No antifungal activity was detected against the filamentous fungus Aspergillus brasiliensis and the yeasts Saccharomyces cerevisiae, Candida parapsilosis, and Candida albicans. In vivo, EECM alleviated the clinical signs of colitis, reduced histological damage, and modulated hematological and biochemical parameters. Overall, EECM exhibited significant antioxidant and anti-inflammatory activities and may represent a promising natural candidate for IBD management. Further investigations into chronic experimental models are necessary to establish their therapeutic relevance.

Background: Chronic relapsing colitis involves immune dysregulation and oxidative stress, making monotherapies often insufficient. This study investigates a therapeutic strategy combining doxycycline (Dox), an immunomodulatory antibiotic, with Arthrospira platensis extracts to enhance anti-inflammatory and antioxidant effects, improving remission and controlling relapse. Methods: Ethanolic (ES) and aqueous (AS) extracts of A. platensis were chemically characterized by GC-MS after derivatization. Colitis was induced in mice using two intrarectal DNBS administrations spaced 7 days apart, with oral treatments (Dox, ES, AS, or combinations) given daily between doses. Disease progression was evaluated through clinical monitoring, histological scoring, and biochemical analysis, including MPO and CAT activities, as well as NO, MDA, and GSH levels. Results: GC-MS identified 16 bioactive compounds in each extract. ES contained mainly fatty acids and amino acids, whereas AS was rich in polysaccharides and phytol. Combined doxycycline and A. platensis extracts significantly enhanced recovery in reactivated DNBS colitis compared to monotherapies. Each treatment alone reduced disease severity, but their combination showed synergistic effects, significantly reducing disease activity index (p < 0.001), restoring mucosal integrity, and modulating inflammatory and oxidative markers (p < 0.001). Conclusion: Doxycycline potentiates the anti-colitic effects of A. platensis extracts via complementary mechanisms, offering a promising combination for managing relapsing colitis.

Inflammatory bowel diseases (IBDs) are complex disorders involving interconnected immune, oxidative, and microbial dysregulations. Arthrospira platensis (Spirulina) is a rich source of bioactive compounds with antioxidant, anti-inflammatory, and immunomodulatory properties. This study investigates the pharmacological efficacy of its aqueous extract (APA) in mitigating 2,4-Dinitrobenzene Sulfonic Acid (DNBS)-induced sub-chronic colitis with a focus on restoring redox balance and modulating gut microbiota composition. APA’s antioxidant capacity was assessed in vitro by 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulphonic) acid (ABTS) radical scavenging, and metal chelation assays. In vivo, BALB/c mice received two DNBS inductions to establish sub-chronic colitis and were treated with APA (50, 100, and 200 mg/kg). Therapeutic efficacy was assessed through clinical scoring, histopathological assessment, biochemical analysis, and gut microbiota profiling based on 16S rRNA gene sequencing. APA exhibited strong antioxidant activity and significantly attenuated colitis severity, as evidenced by reduced Disease Activity Index (DAI) scores, decreased colon inflammation, suppression of Myeloperoxidase (MPO)-mediated neutrophil infiltration, and modulation of redox biomarkers. Moreover, metagenomic profiling revealed APA-induced modulation of the gut microbiota, mainly through a decreased abundance of pathogenic genera such as Staphylococcus and Enterobacteriaceae. APA demonstrates potent antioxidant, anti-inflammatory, and microbiota-modulating activities, supporting its potential as a complementary therapy for IBDs and encouraging further clinical studies.

Arthrospira platensis, a filamentous photosynthetic cyanobacterium, is widely recognized for its high nutritional value, broad spectrum of bioactive compounds, and excellent safety profile, making it a promising natural source for health-promoting applications. This study aimed to profile the phenolic constituents of an ethanolic extract of A. platensis (EAP) using HPLC-DAD-ESI-MS and to investigate its pharmacological effects in attenuating acute and sub-chronic experimental colitis, as well as its antioxidant and antifungal properties. Colitis was induced in BALB/c mice by intrarectal administration of 2,4-dinitrobenzenesulfonic acid (DNBS), followed by oral administration of EAP at doses of 50, 100, and 200 mg/kg. Phenolic profiling revealed eight major compounds, with a cumulative content of 6.777 mg/g of extract, with Pyrogallol, Ferulic acid, and Chlorogenic acid being the most abundant. In vivo, EAP treatment significantly reduced the Disease Activity Index (DAI), alleviated macroscopic colonic damage, and preserved colonic mucosal integrity in both inflammatory phases. Biochemical analyses revealed significant reductions in myeloperoxidase (MPO) activity, nitric oxide (NO), and malondialdehyde (MDA) levels, accompanied by increased reduced glutathione (GSH) content and catalase activity. In vitro, EAP demonstrated notable antioxidant effects, including 56% DPPH and 47% ABTS radical scavenging activities, and an 81% ferrous ion-chelating capacity. Furthermore, it exhibited antifungal activity, with inhibition zones of 20 mm against Candida albicans and 15 mm against Aspergillus flavus, respectively. These findings highlight the multitarget bioactivity of EAP and support its potential as a natural agent for managing intestinal inflammation and oxidative stress across both acute and sub-chronic phases.

Combretum micranthum G. Don (kinkeliba) is a medicinal plant traditionally employed in West Africa for its diuretic and gastrointestinal therapeutic properties. Despite its extensive ethnomedicinal use, comprehensive toxicological assessments are still lacking. This study aimed to characterize the phenolic composition of C. micranthum ethanolic leaf extract using HPLC-DAD-ESI-MS and evaluate its acute and subacute oral toxicity in BALB/c mice, per OECD Guideline 420. Female mice received oral doses of 50, 300, and 2000 mg/kg of extract for acute toxicity assessment for 14 days. In the subacute study, both sexes were administered daily doses at the same concentrations over 28 days. Clinical signs, body weight, and food and water consumption were regularly monitored throughout both protocols. At the end of each study, hematological, biochemical, and histopathological parameters were analyzed. Phenolic profiling revealed nine major compounds with a total of 293.54 mg/g extract. No mortality or significant clinical manifestations were observed at any dose. However, significant variations in platelet counts and amylase activity were noted in the acute phase. In the subacute model, slight, non-critical alterations in hepatic and renal biomarkers were observed, without signs of systemic toxicity. Histopathological examination revealed similar lesions in both acute and subacute phases, including multifocal inflammatory infiltrates (lymphocytes and neutrophils) in the periportal area of the liver, minimal bacterial overgrowth in the superficial layer of the gastric mucosa, minimal medullary mineralization and inflammatory infiltrates with lymphocytes in the kidneys, and minimal to moderate vacuolization in the pancreatic acini. These results indicate that C. micranthum ethanolic extract is relatively safe at the tested doses, reinforcing its traditional use and supporting further research into its pharmacological potential.

Background: The most common Inflammatory Bowel Diseases (IBD) affecting the gastrointestinal system are Crohn's disease and ulcerative colitis. However, the usual therapies for them are associated with a multitude of side effects. The blue-green microalgae Arthrospira platensis is known for its safety profile, nutritional, and medicinal properties in the treatment of different inflammatory and gastrointestinal disorders. Objective: The objective of this study was to investigate the potential intestinal anti-inflammatory effects of the aqueous extract derived from Arthrospira platensis (AAP) in a mouse model of DNBS-induced colitis. Methods: GC-MS and FTIR-ATR were used to determine the different types of chemical compounds found in the AAP extract. BALB/c mice that received DNBS intrarectally were treated with three doses (50, 100 and 200 mg/kg) of AAP for three days. The inflammatory status was assessed daily using a Disease Activity Index (DAI). Mice were sacrificed on the third day, and the extent of colonic damage was evaluated through both macroscopic and histological examinations. Finally, biochemical assays of different markers (MDA, NO, and GSH) were performed. Results: The GC-MS analysis revealed the presence of eleven bioactive compounds, including 2- thiophenecarboxylic acid, 2-biphenyl ester, palmitic acid, 2-linoleoyl glycerol, ethyl isoallocholate, and methyl palmitate. In addition, FTIR spectroscopy revealed the presence of amino, hydroxyl, and glucosidic groups. The treatment of colitic mice with AAP decreased the severity of colitis, as demonstrated by the improvement in the clinical score and the reduction of colonic tissue damage, as well as the modulation of the local biochemical marker levels. Conclusion: The AAP effectively improves DNBS-induced colitis, but its short treatment duration and focus on acute colitis highlight the need for further research on long-term and chronic effects.