Chemopreventive and immunomodulatory effects of phenolic-rich extract of Commiphora leptophloeos against inflammatory bowel disease: Preclinical evidence

ETHNOPHARMACOLOGY RELEVANCE

Commiphora leptophloeos (Mart.) J.B. Gillet (Burseraceae) is a medicinal plant native to Brazil, popularly known as "imburana". Homemade leaf decoction and maceration were used to treat general inflammatory problems in the Brazilian Northeast population. Our previous research confirmed the anti-inflammatory activity of the C. leptophloeos hydroalcoholic leaf extract.

AIM OF THE STUDY

Inflammatory bowel disease (IBD) is a chronic and relapsing inflammatory disorder of the gut with no ideal treatment to maintain the remissive status. This work aimed to characterize the phytochemical composition and physicochemical properties of the C. leptophloeos hydroalcoholic leaf extract and its efficacy in chemopreventive and immunomodulatory responses in inflammatory bowel disease in non-clinical models.

MATERIALS AND METHODS

Mass spectrometry and physicochemical tests determined the phytochemical profile and physicochemical characteristics of the Commiphora leptophloeos (CL) extract. The chemopreventive and immunomodulatory effects of CL extract (50 and 125 μg/mL) were evaluated in vitro in the RAW 264.7 lipopolysaccharide (LPS) induced cell assay and in vivo in the model of intestinal inflammation induced by 2,4-Dinitrobenzenesulfonic acid (DNBS) in mice when they were treated with CL extract by intragastric gavage (i.g.) at doses of 300, 400 and 500 mg/kg.

RESULTS

Phytochemical annotation of CL extract showed a complex phenolic composition, characterized as phenolic acids and flavonoids, and satisfactory physicochemical characteristics. In addition, CL extract maintained the viability of RAW macrophages, reduced ROS and NO production, and negatively regulated COX-2, iNOS, TNF-α, IL-1β, IL-6, and IL-17 (p < 0.05). In the intestinal inflammation model, CL extract was able to downregulate NF-κB p65/COX-2, mTOR, iNOS, IL-17, decrease levels of malondialdehyde and myeloperoxidase and cytokines TNF-α, IL-1β and IL-6 (p < 0.05).

CONCLUSION

Based on these findings, CL extract reduced inflammatory responses by down-regulating pro-inflammatory markers in macrophages induced by LPS and DNBS-induced colitis in mice through NF-κB p65/COX-2 signaling. CL leaf extract requires further investigation as a candidate for treating inflammatory bowel disease.

Evaluation of the healing properties of Garcinia brasiliensis extracts in a cutaneous wound model

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing is a complex process that can leave pathological scars, especially in case of infections from opportunistic microorganisms. In this context, herbal medicines open up great possibilities for investigation. One of the species of interest native to Brazil is Garcinia brasiliensis ("bacupari"). Traditionally known for treating wounds and ulcers, G. brasiliensis presents anti-inflammatory, antioxidant and antimicrobials properties. But, its wound healing profile in experimental models, in order to validate its efficacy, is still litle studied.

AIM OF THE STUDY

Thus, the objective of this work was to evaluate, in an infected cutanous wound model, the potential of formulations incorporated with G. brasiliensis leaves extracts.

MATERIALS AND METHODS

Crude extract (CE), Ethyl Acetate Fraction (EAF) and Hexanic Fraction (HF) were submitted to phytochemical assays, high performance thin layer chromatography (HTPLC) and cytotoxicity studies. CE and EAF were also tested for microbicidal properties and incorporated in cream and gel formulations at 10% concentration. After stability testing, the gel formulations with CE or EAF at 10% were selected and applied to skin wounds infected or not with Staphylococcus aureus in Wistar rats. The healing potenttial of the extracts was verified by the expression of the protein Annexin A1 (AnxA1), related to the processes of inflammation and antifibrotic function, the cells immunostaining for Gasdermin-D (GSDM-D), a marker of pyroptotic cell death, and the dosage of interleukin-10 (IL-10) and monocyte chemotactic protein (MCP)-1 inflammatory mediators.

RESULTS

Phytochemical studies indicated the presence of compounds of pharmacological interest, including Catechin, Quercetin and Berberine in addition to low cytotoxicity of CE and EAF at 10%. After the 6-day topical treatments, CE and EAF gel formulations demonstrated to control the pruritus formation process. The treatments decreased AnxA1 expression and the amount of cells immunostained for GSDM-D, and increased the expression of MCP-1 in infected wounds.

CONCLUSIONS

Together, the results show important anti-inflammatory profile and skin healing potential of CE and EAF from G. brasiliensis leaves, even in infected lesions, with therapeutic perspectives.

Antihyperglycemic activity of crude extract and isolation of phenolic compounds with antioxidant activity from Moringa oleifera Lam. leaves grown in Southern Brazil

The antihyperglicemic activity of crude extract from Moringa oleifera leaves and isolation of phenolic compounds with antioxidant activity using bioguided assay were employed by the first time in leaves cultivated in Brazil. The hydroalcoholic extract (HE) was produced by using ethanol:water (80:20 v/v) and purified by solid-liquid procedure using solvents in ascending order of polarity. The ethyl acetate fraction (Fr-EtOAc) presented high antioxidant potential and it was purified using chromatographic techniques rendering isolated compounds that were identified from the spectral data. The HE extract (500 mg kg^-1) was adimistrated in diabetic rats induced by streptozotocin and chemical markers and lipid peroxidation in liver and kidney were evaluated. The Fr-EtOAc showed high antioxidant potential by FRAP reduction method (1678 µmol Fe²⁺ g^-1), DPPH and ABTS scavenging methods (526.7 and 671.5 µmol TEAC g^-1 respectively) and ORAC assay (3560.6 µmol TEAC g^-1). Therefore, the Fr-EtOAc was purified and yielded three bioactive subfractions (S-12, S-13 abd S-15) that were rechromatoghaphed in HPLC-SemiPrep. After that, two main bioactive glycosylated flavonoids (isoquercitrin and astragalin) and phenolic acid (3-O-caffeoylquinic acid) were obtained. Additionally, the HE extract provided protection against oxidative damage in liver and kidney of diabetic rats ameliorating endogenous antioxidant defenses by increase catalase (CAT), glutathione S-transferase (GST) and non-protein thiol groups (NPSH) levels as well as decreased the lipid peroxidation in these tissues. Our results indicate that three phenolic compounds with high antioxidant activity were isolated and, the chemical composition of HE crude extract, rich in flavonoids glycosylated could be intimately related to antihyperglycemic action. So, it is possible to suggest that these compounds may be used as chemical biomarkers for this plant in Brazil, ensuring quality and supporting the use of aerial parts in tradicional medicine.