Antinociceptive Potential of Ximenia americana L. Bark Extract and Caffeic Acid: Insights into Pain Modulation Pathways

Ximenia americana L. (Olacaceae) has traditionally been used in folk medicine in the African continent and Brazilian Northeast to treat diseases such as diarrhea, fever, wounds, and pain. This study evaluated the antinociceptive effect of the Ximenia americana L. bark extract (HEXA) and its primary component, caffeic acid (CA), through in vivo assays. The antinociceptive properties were assessed using abdominal writhing, hot plate, and Von Frey tests. Additionally, the study investigated the modulation of various pain signaling pathways using a pharmacological approach. The results demonstrated that all doses of the HEXA extract significantly increased latency in the hot plate test, decreased the number of abdominal contortions, reduced hyperalgesia in the Von Frey test, and inhibited both phases of the formalin test. Caffeic acid reduced licking time in the first phase of the formalin test at all doses, with the highest dose showing significant effects in the second phase. The HEXA extract potentially modulated α2-adrenergic, nitric oxide, glutamatergic, vanilloid, cyclic guanosine monophosphate, and K+-ATP channel-dependent pathways. Conversely, caffeic acid influenced the opioid, glutamatergic, and vanilloid pathways while inhibiting nitric oxide and cyclic guanosine monophosphate. HEXA and CA exhibit significant antinociceptive effects due to their potential interference in multiple pain signaling pathways. While the molecular targets remain to be fully investigated, HEXA and CA demonstrate significant potential for the development of new analgesic drugs.