Antinociceptive Activity of Methanol Extract ofMuntingia calaburaLeaves and the Mechanisms of Action Involved

Abstract

Muntingia calabura L. (family Elaeocarpaceae) has been traditionally used to relieve various pain-related ailments. The present study aimed to determine the antinociceptive activity of methanol extract of M. calabura leaves (MEMC) and to elucidate the possible mechanism of antinociception involved. The in vivo chemicals (acetic acid-induced abdominal constriction and formalin-, capsaicin-, glutamate-, serotonin-induced paw licking test) and thermal (hot plate test) models of nociception were used to evaluate the extract antinociceptive activity. The extract (100, 250, and 500 mg/kg) was administered orally 60 min prior to subjection to the respective test. The results obtained demonstrated that MEMC produced significant (P < 0.05) antinociceptive response in all the chemical- and thermal-induced nociception models, which was reversed after pretreatment with 5 mg/kg naloxone, a non-selective opioid antagonist. Furthermore, pretreatment with L-arginine (a nitric oxide (NO) donor), NG-nitro-L-arginine methyl esters (L-NAME; an inhibitor of NO synthase (NOS)), methylene blue (MB; an inhibitor of cyclic-guanosine monophosphate (cGMP) pathway), or their combination also caused significant (P < 0.05) change in the intensity of the MEMC antinociception. In conclusion, the MEMC antinociceptive activity involves activation of the peripheral and central mechanisms, and modulation via, partly, the opioid receptors and NO/cGMP pathway.

Muntingia calabura: A review of its traditional uses, chemical properties, and pharmacological observations

“…Of all the pharmacological activities reported above, only the antinociceptive, anti-inflammatory, antipyretic, antiulcer, antidiabetic, antihypertensive, and cardioprotective effects were performed using in vivo assays. Taking these doses range as basis for all in vivo investigations cited in this review, reports on antinociceptive using AEMC L , CEMC L , and MEMC L at the doses ranging between 27 and 270, 50 and 500, and 100 and 500 mg/kg, respectively, are considered acceptable (Sani et al, 2012;Zakaria et al, 2006aZakaria et al, , 2007d. Therefore, these findings support the traditional uses of M. calabura in the treatment of headache and stomachache.…”

“…In the latest study, Sani et al (2012) reported on the antinociceptive activity and the possible mechanisms of antinociception of M. calabura leaves collected from Shah Alam, Selangor, Malaysia. The leaves were prepared as MEMC L in the concentrations of 100, 250, and 500 mg/kg and tested using the abdominal constriction test, hot plate test, and formalin test to build the antinociceptive profile of the extract.…”

“…It is also widely cultivated in warm areas in India and Southeast Asia such as Malaysia, Indonesia, and the Philippines. Indeed, in Malaysia, M. calabura is commonly cultivated as roadside trees (Morton, 1987;Sani et al, 2012;Yusof et al, 2011;Zakaria et al, 2006aZakaria et al, ,b, 2007aZakaria et al, -f, 2008Zakaria et al, , 2010Zakaria et al, , 2011.…”

Antinociceptive and Anti-inflammatory Activities of Methanol Extract of Ormosia coccinea (Aubl.) Jacks in vivo

“…The intraperitoneal administration of agents that irritate serous membranes provokes a stereotyped behaviour in the mice which is characterized by abdominal contractions, movements of the body as a whole and twisting of the dorso-abdominal muscles [22] and a reduction in motor activity and motor incoordination [23]. It has been suggested that acetic acid injection into peritoneal cavity leads to increased levels of cyclooxygenases (COX) and lipoxygenase [24] and indirectly leads to the release of endogenous nociceptive mediators such as PGE 2 and PGF 2α [5,20,[25][26][27][28][29][30], serotonin [22,25,26,29,30], histamine [22,26,30,31], bradykinin [21,22,24], substance P [24,25], cytokines (TNF-α, IL-1β, IL-8) [21,24,25,29] and lipoxygenase products [20], which eventually excites the primary afferent nociceptors [25] that contribute to the development of inflammatory pain [22]. The data presented in Fig.…”

“…To provide a confirmation of the central antinociceptive activity of MEOC, we used the hot plate test, since this model is sensitive and specific for strong analgesics (opioids), while peripherally acting analgesics are inactive [23,26,28,35,36]. This model of nociception, predominantly a spinal reflex, is thought to involve supraspinal nociceptive processing [21,27] and has often been used to assess central antinociceptive activity [25,28].…”