No abstract

No abstract

BackgroundThe species Himatanthus drasticus is popularly known in Northeast Brazil as "janaguba" and belongs to the family Apocynaceae. The latex collected from its stem bark is used for several purposes including anti-inflammatory properties and presents among its bioactive constituents the pentacyclic triterpene lupeol. The objective of the present work was to study in vivo and in vitro the lupeol acetate (LA) isolated from the plant latex, in several models of inflammation.MethodsMale Swiss mice (25-30 g, 6-24 animals per group) were administered with LA, 30 min before the test initiation. In the evaluation of analgesic activity the formalin test was used. The anti-inflammatory activity was evaluated by the following tests: paw edema induced by carrageenan and dextran, and the carrageenan-induced neutrophil migration into peritoneal cavities. Furthermore, the effect of LA on the myeloperoxidase release (MPO, an inflammation biomarker) from human neutrophils was also determined, as well as its antioxidant potential by the DPPH assay.ResultsIn the formalin test, LA (10, 25 and 50 mg/kg, i.p.) inhibited both the 1st (neurogenic, 0-5 min) and mainly the 2nd (inflammatory, 20-25 min) phase. Naloxone completely reversed the LA effect, indicating the participation of the opioid system. LA also significantly inhibited carrageenan- and dextran-induced paw edemas, as well as the neutrophil migration to the peritoneal cavity evaluated by the carrageenan-induced pleurisia. In this model, the effect of a very low dose of LA (0.1 mg/kg) was potentiated by the same dose of pentoxifylline (PTX), a known TNF-alpha inhibitor. LA (25 and 50 μg/ml) was also very effective in inhibiting MPO released from stimulated human neutrophils, and significantly decreased the number of cells expressing iNOS activity in the paw of mice submitted to carrageenan-induced edema, suggesting a drug involvement with the NO system.ConclusionsThe anti-inflammatory effect of LA probably involves the opioid system, as indicated by the complete blockade of the opioid antagonist naloxone. Furthermore, the LA effect was potentiated by PTX (a TNF-alpha inhibitor). LA also decreased the number of iNOS cells, suggesting the participation of pro-inflammatory cytokines and the NO system in the drug action.

(-)-α-Bisabolol is an unsaturated, optically active sesquiterpene alcohol obtained by the direct distillation of essential oil from plants such as Vanillosmopsis erythropappa and Matricaria chamomilla. (-)-α-Bisabolol has generated considerable economic interest, as it possesses a delicate floral odour and has been shown to have antiseptic and gastroprotective activities. In this study, (-)-α-bisabolol was tested in standardised rodent models by gavage administration at doses of 100 and 200 mg/kg in the models of inflammation and 25 and 50 mg/kg in the models of nociception. In the inflammatory models of paw oedema induced by carrageenan and dextran, the mice treated with (-)-α-bisabolol showed smaller oedemas compared to animals treated only with the vehicle. (-)-α-Bisabolol was capable of reducing paw oedemas induced by 5-HT but not oedemas induced by histamine. (-)-α-Bisabolol demonstrated anti-nociceptive activity in the models of visceral nociception induced by acetic acid and in the second phase of the nociception test induced by the intraplantar administration of formalin. (-)-α-Bisabolol did not have any effect in a thermal nociception model using a hot plate but was able to diminish mechanical inflammatory hypernociception evoked by carrageenan. These findings suggest that the anti-nociceptive action of (-)-α-bisabolol is not linked to a central mechanism but instead is related to the inflammatory process. (-)-α-Bisabolol was able to decrease leukocyte migration, protein extravasations and the amount of TNF-α to the peritoneal cavity in response to carrageenan. Additionally, (-)-α-bisabolol reduced neutrophil degranulation in response to phorbol-myristate-acetate. We demonstrate, for the first time, the peripheral anti-inflammatory and anti-nociceptive activities of (-)-α-bisabolol.

No abstract

Our data indicate that anti-inflammatory and antioxidant effects, involve the inhibition of iNOS and TNF-alpha, among other properties, and these encourage clinical studies of these compounds for new therapeutic applications, especially those were inflammation plays a role.

Camellia sinensis (green tea) is largely consumed, mainly in Asia. It possesses several biological effects such as antioxidant and anti-inflammatory properties. The objectives were to investigate the neuroprotective actions of the standardized extract (CS), epicatechin (EC) and epigallocatechin gallate (EGCG), on a model of Parkinson's disease. Male Wistar rats were divided into SO (sham-operated controls), untreated 6-OHDA-lesioned and 6-OHDA-lesioned treated for 2 weeks with CS (25, 50, or 100 mg/kg), EC (10 mg/kg), or EGCG (10 mg/kg) groups. One hour after the last administration, animals were submitted to behavioral tests and euthanized and their striata and hippocampi were dissected for neurochemical (DA, DOPAC, and HVA) and antioxidant activity determinations, as well as immunohistochemistry evaluations (TH, COX-2, and iNOS). The results showed that CS and catechins reverted behavioral changes, indicating neuroprotection manifested as decreased rotational behavior, increased locomotor activity, antidepressive effects, and improvement of cognitive dysfunction, as compared to the untreated 6-OHDA-lesioned group. Besides, CS, EP, and EGCG reversed the striatal oxidative stress and immunohistochemistry alterations. These results show that the neuroprotective effects of CS and its catechins are probably and in great part due to its powerful antioxidant and anti-inflammatory properties, pointing out their potential for the prevention and treatment of PD.

Spirulina platensis (Spi) is a microalga presenting high contents of proteins, γ-linolenic acid, vitamins and minerals, and showing many biological activities. It is a promising drug for the treatment of diseases including diabetes. The objectives of this work were to study Spi effects on alloxan-induced diabetic rats, and associate this to its anti-inflammatory activity. The treatment with Spi (25, 50 or 100 mg/kg, p.o.) started 48 h after the alloxan injection, continuing for 5 or 10 days. Biochemical parameters were measured in sera of treated and untreated animals. The anti-inflammatory activity of Spi was assessed by the formalin test and carrageenan-induced paw edema in mice. Immunostainings for TNF-alpha were carried out in the carrageenan-induced paw edema in rats, before and after the Spi treatment, and its effect on the release of myeloperoxidase from human neutrophils was also determined. Spi decreased glycemia as well as triglyceride and total cholesterol levels of diabetic rats. Levels of urea and creatinine were also reduced, while liver transaminases were unaltered. Spi also decreased dose-dependently the 1st (neurogenic) and mainly the 2nd phase (inflammatory) of the formalin test, as well as the carrageenan-induced paw edema in mice. The anti-inflammatory effect of Spi was further confirmed by decreases in TNF-alpha immunostaining in the inflamed paw and in the myeloperoxidase release from human neutrophils. The results showed that the anti-diabetic effect of S. platensis is already manifested after a 5-day treatment. Additionally, considering the relationship between diabetes and inflammation, the microalga anti-inflammatory action may also be involved.