Anti-inflammatory activity of the sesquiterpene lactone diacethylpiptocarphol in dextransulfate sodium-induced colitis in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Sesquiterpene lactones are organic compounds derived mainly from plants that exhibit anti-inflammatory and antitumor activities being one of the key mechanism of action of NF-kB pathway and synthesis of cytokines such as IL-1 and TNF- α. AIM OF THE STUDY: The overall objective of the present study was to evaluate the anti-inflammatory action of a sesquiterpene lactone diacethylpiptocarphol (DPC) from Vernonia scorpioides (Lam.) Pers. and parthenolide (PTH) in Balb-c mice with DSS-induced colitis. MATERIALS AND METHODS: The anti-inflammatory effects of Intraperitonial administration of DPC (5 mg/kg/day) were evaluated in Balb/c mice with DSS-induced colitis, and further the body weight measurement, TNF-α and TGF-ß level was determined. RESULTS: After intraperitoneal treatment for one week, DSS-induced colitis was significantly reduced in mice treated with either of both sesquiterpenes lactones, as witnessed by reduced cellular infiltration, tissue damage, TNF-α production, and enhanced production of TGF-ß. CONCLUSIONS: Sesquiterpene lactone DPC, isolated from Vernonia scorpioides showed anti-inflammatory activity, in this experimental model of colitis the sesquiterpene lactones DPC and PTH exhibit equal anti-inflammatory activity.

Cytotoxic activity of the dichloromethane fraction from Vernonia scorpioides (Lam.) Pers. (Asteraceae) against Ehrlich's tumor cells in mice.

Vernonia scorpioides has been widely used in Brazil to treat skin problems and chronic wounds, such as ulcers of the lower limbs and diabetic lesions. In the present study, we investigated the effect of a dichloromethane (DCM) fraction of V. scorpioides leaf extract on Ehrlich ascitic and solid tumor-bearing mice. The animals were treated once a day with the DCM fraction at a concentration of 5 mg/kg, administered ip during and after the development of the tumor. The lifespan, weight, number and type of leukocytes, number of tumor cells, volume of solid and ascitic tumors were measured. The development of the tumor with pre-treated tumor cells in vitro with the DCM fraction (5 mg/kg) was analyzed and the animals were sacrificed after 7 days. The DCM fraction (5 mg/kg) totally inhibited tumor development when in direct contact with tumor cells, and also ascitic tumor development with in vitro treatment or when administered ip, in loco (after 7 days). Animals treated with the DCM fraction increased their lifespan ca. 2 weeks and maintained their body weight for 30 days. When applied immediately after the inoculation of the tumor cells in vivo, it totally abolished tumor development, with tumor development only decreasing when treatment was started 3 days after the tumor challenge. These data suggest an antineoplastic activity of the fraction. Oral or ip administration of DCM fraction (5 mg/kg) for 7 days did not reduce the solid tumor volume. The cytotoxic activity described here differs from the conventional immune suppressing profile of standard chemotherapy because it increases neutrophil influx to the peritoneal cavity. These results show that, besides exhibiting a tumoricidal activity, the DCM fraction also exhibits inflammatory activity.

Cytotoxic activity of the dichloromethane fraction from Vernonia scorpioides (Lam.) Pers. (Asteraceae) against Ehrlich's tumor cells in mice

Vernonia scorpioides has been widely used in Brazil to treat skin problems and chronic wounds, such as ulcers of the lower limbs and diabetic lesions. In the present study, we investigated the effect of a dichloromethane (DCM) fraction of V. scorpioides leaf extract on Ehrlich ascitic and solid tumor-bearing mice. The animals were treated once a day with the DCM fraction at a concentration of 5 mg/kg, administered ip during and after the development of the tumor. The lifespan, weight, number and type of leukocytes, number of tumor cells, volume of solid and ascitic tumors were measured. The development of the tumor with pre-treated tumor cells in vitro with the DCM fraction (5 mg/kg) was analyzed and the animals were sacrificed after 7 days. The DCM fraction (5 mg/kg) totally inhibited tumor development when in direct contact with tumor cells, and also ascitic tumor development with in vitro treatment or when administered ip, in loco (after 7 days). Animals treated with the DCM fraction increased their lifespan ca. 2 weeks and maintained their body weight for 30 days. When applied immediately after the inoculation of the tumor cells in vivo, it totally abolished tumor development, with tumor development only decreasing when treatment was started 3 days after the tumor challenge. These data suggest an antineoplastic activity of the fraction. Oral or ip administration of DCM fraction (5 mg/kg) for 7 days did not reduce the solid tumor volume. The cytotoxic activity described here differs from the conventional immune suppressing profile of standard chemotherapy because it increases neutrophil influx to the peritoneal cavity. These results show that, besides exhibiting a tumoricidal activity, the DCM fraction also exhibits inflammatory activity.

Effects of the topical application of the extract of Vernonia scorpioides on excisional wounds in mice

Vernonia scorpioides is traditionally widely used in Brazil to treat skin problems, including healing of chronic wounds, such as ulcers of the lower limbs and diabetic wounds. This work investigated the healing process on excisional wounds in the skin of mice, treated daily with an ointment containing 20 percent of the ethanol extract of the leaves of Vernonia scorpioides, compared with the control. A skin wound area of about 4 mm was excised on anaesthetised mice, and after 3, 7 and 14 days of treatment, the lesions were surgically removed and histologically processed. Wound healing activity was determined by the percentage of necrosis area, mononuclear inflammatory cells, fibroblasts and blood vessels. In the acute phase of healing, treatment with piracá extract enlarged the lesions and intensified the necrosis area, compared with the control group. However, the treatment did not inhibit either the recruitment and stimulation of inflammatory cells or the repair process. The results obtained indicate a harmful action of the extract immediately after tissue excision, demonstrated by the increased area of necrotic tissue, clotting and exudates formed in the treated groups. However, the extract did not inhibit the formation of granulation tissue.

Adjuvant modulation of the immune responses and the outcome of infection with Chlamydia pneumoniae.

Immunization with different adjuvants resulted in antithetic outcomes of infection with Chlamydia pneumoniae. Immunization with the outer major protein-2 from C. pneumoniae (OMP-2) emulsified in Freund's complete adjuvant (FCA) thus increased the susceptibility of mice to infection with the bacteria. The detrimental effect was not observed upon inoculation of irrelevant antigens or major outer membrane protein (MOMP) in FCA, but was also observed after immunization with FCA-chlamydial heat shock protein-60 (HSP-60). The harmful effect of FCA-OMP-2 depended on the presence of both CD4+ and CD8+ cells and was mediated by IL-10, as shown using gene-ablated mice. The increased susceptibility to infection caused by FCA-OMP-2 immunization was long-lasting and observed in mice infected 4 months after the last dose of immunogen. In contrast, partial protection against C. pneumoniae was observed when FCA was replaced with oligodeoxynucleotides containing immunostimulatory CpG motifs mixed with Freund's incomplete adjuvant (FIA-IS-CpG). These polar outcomes of infection related to the cytokine pattern: antigen-stimulated spleen cells from FCA-OMP-2-immunized mice showed higher IL-10/IFN-gamma ratios than FIA-IS-CpG-OMP-2-immunized animals. In agreement, sera from FCA-OMP-2 showed higher anti-OMP-2 IgG1/IgG2a ratios than FIA-IS-CpG-OMP-2-immunized animals. Finally, OMP-2 also generated a protective response when delivered by a eukaryotic expression vector in tandem with CTLA4, a procedure that targeted OMP-2 to antigen-presenting cells.

Expression of NO-synthase in cells of foreign-body and BCG-induced granulomata in mice: influence of L-NAME on the evolution of the lesion.

The microbicidal activity of macrophages in an inflammatory milieu has been related to the production of a large number of cytokins and intermediary metabolites of oxygen and nitrogen among them, nitric oxide (NO). Considering that granulomatous inflammation is predominantly composed of macrophages and epithelioid cells, we decided to investigate the participation of NO in this peculiar type of inflammation. Two models were used: glass cover slip implantation into the subcutaneous tissue of mice and, the inoculation of live bacillus Calmette-Guérin (BCG) into the footpad of the animals. Using a histochemical method for the detection of NO synthase and of the concentration of citrulin metabolized by cells obtained from cover slips implanted on different time intervals or BCG-activated peritoneal cells, it was possible to demonstrate that epithelioid cells do not produce NO. Cells from granuloma induced by BCG inoculation express NO synthase, with different degrees of reactivity with a higher intensity in the cytoplasm of cells located in the edge of the lesions. The expression of NO synthase in the cytoplasm of these cells decreases with the age of the lesions. It could also be demonstrated that in mice treated with l-name, an inhibitor of NO metabolism, the lesions induced by BCG lost the granulomatous architecture, were necrotic, and had a significant increase in the bacillary load of the lesion. These data allow us to conclude that NO production by macrophages is a determining factor in the organization of the granulomatous lesion and that it also controls the bacterial load in BCG-induced lesions in mice.