Effects of virgin olive oil phenolics on scavenging of reactive nitrogen species and upon nitrergic neurotransmission.

The major phenolics from the polar fraction of virgin olive oil (caffeic acid, oleuropein, tyrosol and hydroxytyrosol) have well-established antioxidant activities but their effects on reactive nitrogen species and nitrergic neurotransmission have not been fully investigated. The three catechol compounds were active as scavengers of nitric oxide generated spontaneously from the decomposition of sodium nitroprusside (approximately 50% inhibition achieved at 75 microM), and had similar ability to scavenge chemically generated peroxynitrite, as determined by an alpha1-antiproteinase inactivation assay (67.2%-92.4% reduction when added at 1 mM). Tyrosol was less active in these tests, but does not possess the catechol functionality. Despite their ability to interact with chemically prepared nitric oxide, neither oleuropein nor hydroxytyrosol at 5 microM altered NO*-mediated relaxations of the nerve-stimulated rat anococcygeus preparation, but this may be because the nitrergic transmitter is protected from the effects of externally applied scavengers. In conclusion, the phenolics found in virgin olive oil possess ability to scavenge reactive oxygen and nitrogen species that are implicated in human pathologies, but their impact may be restricted to those species present in the extracellular environment.

Anti-inflammatory activity of Agave intermixta Trel. and Cissus sicyoides L., species used in the Caribbean traditional medicine.

Agave intermixta Trel. and Cissus sicyoides L. are two tropical plants originating from the Dominican Republic. Aqueous extracts from these species are used in traditional medicine. In contrast, biological activity and toxicity of these plants are not yet evaluated systematically. The aim of the present work is to investigate a potential anti-inflammatory activity, and to elucidate the toxicity of the extracts. No lethal effects were produced after oral administration of the extracts. The values of the medium lethal doses after intraperitoneal administration were quite high for both species, although A. intermixta seems to be rather more toxic than C. sicyoides. The anti-inflammatory effects have been investigated in two experimental in vivo models. The carrageenan-induced rat paw oedema was chosen as a model for general inflammation, and the mice ear oedema test using tetradecanoylphorbol acetate as inflammatory agent as a model of topical inflammation. Dry extracts from decoctions of A. intermixta leaves and C. sicyoides stems were administered in doses of 300 and 500 mg/kg (p.o.) in the general model, and in doses of 3 and 5 mg/mouse ear for both plants in the topical model. In the general anti-inflammation assay, the oral administration of both extracts produced a significant anti-inflammatory effect, most pronounced for A. intermixta than for C. sicyoides. In the topical model, the administration of both extracts produced similar inhibitions of the oedema, with a reduction of approximately 50% in comparison with the control group. In homogenated tissue samples from the inflamed areas, a distinct decrease in the level of myeloperoxidase enzyme was noted.

Prognostic significance of pathological response of primary tumor and metastatic axillary lymph nodes after neoadjuvant chemotherapy for locally advanced breast carcinoma.

PURPOSE: The prognostic significance of pathological response of primary tumor and metastatic axillary lymph nodes after neoadjuvant chemotherapy was assessed in patients with noninflammatory locally advanced breast carcinoma. PATIENTS AND METHODS: Between January 1989 and April 1995, 148 consecutive patients with locally advanced breast carcinoma participated in the study. Of these, 140 fully evaluable patients (67, stage IIIA; 73, stage IIIB) were treated with three courses of 5-fluorouracil, doxorubicin, and cyclophosphamide (FAC), followed by modified radical mastectomy when technically feasible or definitive radiation therapy. The median age was 53 years (range, 26 to 75 years); 55% of patients were postmenopausal. RESULTS: Objective response was recorded in 99 of 140 patients (71%; 95% confidence interval, 63% to 79%). Complete response occurred in 11 patients (8%), and partial response occurred in 88 patients (63%). No change was recorded in 37 patients (26%), and progressive disease occurred in 4 patients (3%). One hundred and thirty-six patients underwent the planned surgery. Maximal pathological response of the primary tumor (in situ carcinoma or minimal microscopic residual tumor) was observed in 24 (18%); 112 patients (82%) presented minimal pathological response of the primary tumor (gross residual tumor). The number of metastatic axillary nodes after neoadjuvant chemotherapy was as follows: N0, 39 patients (29%); N1-N3, 35 patients (26%); > N3, 62 patients (45%). Considering the initial TNM status, 75% of the patients had decreases in tumor compartment after neoadjuvant chemotherapy. Also, 31% and 23% of patients with clinical N1 and N2, respectively, showed uninvolved axillary lymph nodes. A significant correlation was noted between pathological response of primary tumor and the number of metastatic axillary lymph nodes. Median disease-free survival was 34 months, whereas median overall survival was 66 months. Pathological responses of both primary tumor and metastatic axillary lymph nodes were strongly correlated with disease-free survival and overall survival in univariate analyses. Additionally, in a proportional hazard regression model and in an accelerated failure time model, metastatic axillary lymph nodes significantly influenced both disease-free survival and overall survival, whereas pathological response of primary tumor did so on disease-free survival only. CONCLUSION: After neoadjuvant chemotherapy, pathological responses of both primary tumor and metastatic axillary lymph nodes had a marked prognostic significance and influenced outcome for patients with locally advanced breast carcinoma. Our results suggest that maximal tumor shrinkage and sterilization of potentially involved axillary nodes may represent a major goal of neoadjuvant chemotherapy. Further studies are warranted to clarify whether these results reflect the therapeutic effect or intrinsic biologic factors of the tumor.

Double modulation of 5-fluorouracil by methotrexate and high-dose L-leucovorin in advanced colorectal cancer.

A phase II trial was performed to evaluate the efficacy and toxicity of a double modulation of 5-fluorouracil (5-FU) by methotrexate (MTX) and L-leucovorin (L-LV) in patients with advanced recurrent (inoperable) or metastatic colorectal carcinoma (ACC). Between July 1993 and October 1995, 41 patients with ACC received a regimen that consisted of MTX 150 mg/m2 i.v., infused over a 20-minute period at hour 0, followed 19 hours later by L-LV 250 mg/m2 in a 2-hour i.v. infusion. 5-FU, 900 mg/m2, was administered by i.v. push injection at hour 20. Beginning 24 hours after MTX administration, all patients received four doses of L-LV, 15 mg/m2 i.m., every 6 hours. Cycles were repeated every 15 days. Two patients were not assessable for response. Objective regression was observed in 11 of 39 (28%) patients, [95% confidence interval (CI), 14-42%]. One (2%) patient achieved complete response (CR) and 10 (26%) partial response (PR). No change was recorded in 15 (39%) patients and progressive disease was noted in 13 (33%) patients. The median time to treatment failure was 6 months and the median survival time was 10 months. Toxicity was within acceptable limits, but one therapy-related death due to severe leukopenia was observed. The dose-limiting toxicity was mucositis. Eight episodes of grade 3 or 4 stomatitis were observed, and were responsible for dosage modifications of MTX and 5-FU. In conclusion, further in experimental and clinical studies are clearly necessary in order to design the best modulatory strategy of 5-FU.