1–10 mg/kg) produced dose related inhibition of the abdominal constrictions induced by acetic acid, a screening model for the assessment of analgesic or anti-inflammatory properties of new agents
(Fig. 5A). STK-1000R displayed a mean ID50 of 0.47 mg/kg (95% confidence limits 0.18–1.19), and at 10 mg/kg inhibited the number of writhes by 78 ± 6%. It is well known that acetic acid causes an inflammatory nociception, with direct activation of peripheral polymodal nociceptors GSK-3 signaling pathway and release of endogenous inflammatory mediators such as bradykinin, prostaglandin and cytokines (TNF-α, IL-1β and IL-8) (Rodrigues et al., 2012). To confirm the effect of STK-1000R on inflammatory pain, we performed the formalin test. This model is constituted by two distinct phases: the neurogenic pain (phase I), which results from the direct irritating effect on nociceptors, and the inflammatory pain (phase II), mediated by a combination of peripheral input and spinal cord sensitization (Tjolsen, Berge, Hunskaar, Rosland, & Hole, 1992). Similarly, intraperitoneal administration of STK-1000R (0.01, 0.1, and 1 mg/kg) inhibited only the inflammatory phase of formalin-induced nociceptive response, yielding ID50 of 0.09 (0.03–0.23) mg/kg (maximal inhibition of 80 ± 6% for STK-1000R 1 mg/kg) (Fig. 5B and
C). These findings suggest that Sirolimus in vivo the galactoarabinoglucuronoxylan present in the pulp of tamarillo (S. betaceum) promotes analgesic effects through anti-inflammatory mechanisms. This research was supported by Projeto universal (Process 475747/2010-0) provided by CNPq foundation (Brazil) and by Tacrolimus (FK506) PRONEX-Carboidratos. C.H. Baggio is recipient of post-doctoral scholarship from
the CNPq. The authors are grateful to Alceu and Maria Mach for providing the plant material and to Dr. Guilherme L. Sassaki and Arquimedes Santana-Filho for recording the NMR spectra. “
“Xylopia frutescens Aubl. (Annonaceae) is a medicinal plant found in Central and South America, Africa and Asia ( Braga, 1976). In Brazil, it is popularly known as “embira”, “embira-vermelha” and “pau carne”, and its seeds are used in folk medicine as a bladder stimulant, to trigger menstruation, and to combat rheumatism, halitosis, tooth decay and intestinal diseases ( Correa, 1984 and Takahashi et al., 1995). The seeds have an acrid, aromatic taste and are used instead of pepper in Guyana. In Panama, its leaves are used to treat fever ( Joly et al., 1987). Studies examining the biological properties of X. frutescens have demonstrated antibacterial, antifungal, anti-viral, antiplasmodial and anti-inflammatory activities ( Braga et al., 2000, Fournier et al., 1994, Jenett-Siems et al., 1999 and Matsuse et al., 1999). Numerous studies have demonstrated anticancer activity for the essential oils obtained from medicinal plants (Asekun and Adeniyi, 2004, Britto et al., 2012, Quintans et al., 2013, Ribeiro et al., 2012 and Sœur et al., 2011).