Evaluation of the antiedematogenic and anti-inflammatory properties of Ximenia americana L. (Olacaceae) bark extract in experimental models of inflammation

Edema is one of the obvious indicators of inflammation and a crucial factor to take into account when assessing a substance's capacity to reduce inflammation. We aimed to evaluate the antiedematogenic and anti-inflammatory profile of the hydroethanolic barks extract of Ximenia americana (HEXA). The possible antiedematogenic and anti-inflammatory effect of EHXA (50, 100 mg/kg and 250 mg/kg v.o) was evaluated using the paw edema induced by carrageenan, zymosan, dextran, CFA and by different agents inflammatory (serotonin, histamine, arachidonic acid and PGE2), and pleurisy model induced by carrageenan and its action on IL-1β and TNF-α levels was also evaluated. HEXA demonstrated a significant antiedematogenic effect at concentrations of 50, 100 and 250 mg/kg on paw edema induced by carrageenan, zymosan and dextran. However, the concentration of 50 mg/kg as standard, demonstrating the effect in the subchronic model, induced CFA with inhibition of 59.06 %. In models of histamine-induced paw edema, HEXA showed inhibition of - 30 min: 40.49 %, 60 min: 44.70 % and 90 min: 48.98 %; serotonin inhibition - 30 min: 57.09 %, 60 min: 66.04 % and 90 min: 61.79 %; arachidonic acid inhibition - 15 min: 36.54 %, 30 min: 51.10 %, 45 min: 50.32 % and 60 min: 76.17 %; and PGE2 inhibition - 15 min: 67.78 %, 30 min: 62.30 %, 45 min: 54.25 % and 60 min: 47.92 %. HEXA significantly reduced (p < 0.01) leukocyte migration in the pleurisy model and reduced TNF-α and IL-1β levels in pleural lavage (p < 0.0001). The results showed that HEXA has the potential to have an antiedematogenic impact in both acute and chronic inflammation processes, with a putative mode of action including the suppression or regulation of inflammatory mediators.

Urginea indica attenuated rheumatoid arthritis and inflammatory paw edema in diverse animal models of acute and chronic inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Urginea indica has been used in the traditional system of medicine to treat various inflammatory diseases.

AIM OF THE STUDY

Present study investigates the effects of aqueous and ethanolic extracts of U. indica on joint inflammation using different models of acute and chronic inflammation.

MATERIALS AND METHODS

FCA-induced arthritic rat model, a model of chronic joint inflammation, was used to evaluate the anti-arthritic effects of plant extracts (500 mg/kg, each extract). Macroscopic arthritic scoring, digital water plethysmometery, and histopathological evaluation (H & E staining) were performed to measure the severity of arthritis. Acute inflammatory models like, carrageenan-, histamine- and serotonin-induced paw edema models were used to evaluate effects of U. indica, and supported by xylene-induced ear edema model.

RESULTS

Both extracts significantly inhibited arthritic development, paw edema, bone erosion, pannus formation, and infiltration of inflammatory cells. Treatment with U. indica extracts resulted in almost normalization of altered counts of white blood cells (WBCs), platelets, and red blood cells (RBCs), along with Hb content. Both extracts were found safe in terms of hepatotoxicity and nephrotoxicity as determined by non-significant difference of alanine aminotransferase (ALT), aspartate transaminase (AST), urea, and creatinine levels among all groups. U. indica significantly attenuated carrageenan-induced paw edema. There are several mechanisms involved in the attenuation of carrageenan-induced paw edema; inhibition of autacoids is one of those important mechanisms. The autacoid inhibition was confirmed by reduction of histamine- and serotonin-induced paw edema found in plant extract treated groups. Suppression of xylene-induced ear edema by plant extract further validated the suggested mechanism of autacoid inhibition. GC-MS analysis showed the presence of isopropyl palmitate in the highest quantity (26.852%).

CONCLUSIONS

This study validated the folkloric uses of U. indica and showed that plant possessed anti-arthritic and anti-inflammatory properties which might be ascribed to inhibition of autacoids.

Fundamentals of and Critical Issues in Lipid Autacoid Medicine: A Review

The identification of a number of families of lipid signal molecules since the 1990s created new therapeutic possibilities for a great number of disorders characterized by chronic inflammation and pain. These lipid autacoids have been explored in a great variety of animal models related to inflammation, pain, (neuro-)protection, and repair. Based on the data from these models, as well as on a number of proof of principle studies in the clinic in indications such as neuropathic pain, a new chapter in medicine is about to begin. We would like to introduce the term “Autacoid Pain Medicine” for this chapter. There are, however, a number of methodological and strategic issues to overcome in this field. One of the roadblocks is related to patent strategies around families of these molecules. As this is not always recognized we will present a number of examples.