Artemisia dracunculus Extracts Obtained by Organic Solvents and Supercritical CO2 Produce Cytotoxic and Antitumor Effects in Mice with L5178Y Lymphoma.

We investigated the cytotoxic and antitumor effects of nine leaf extracts from Artemisia dracunculus (Tarragon). Five extracts were obtained using different organic solvents and four by supercritical CO2. The cytotoxic effects were expressed as IC50 in 100, 80, 80, 100, and 80 µg/mL by respective solvents: hexane, ethyl acetate, acetone, ethanol, and acetonitrile in L5178Y lymphoma cells. For supercritical CO2 extract A, IC50 was 100 µg/mL; for extracts C and D, IC50 was 150 µg/mL. The antitumor activity was assessed through a tumor growth inhibition test that measured ascites fluid volume and tumor cell counts of BALB/c mice (2 × 104 cells L5178Y i.p.). Twenty-four hours after inoculation, mice were treated with 100 mg/kg of acetonitrile extract or extract SF-A daily for 15 days in independent groups of five mice, using two administration routes. We observed tumor evolution with and without treatment. Without treatment, tumor evolution was 17,969 × 106 ± 5485 L5178Y cells in 2.6 mL ascites volume, whereas the orally treated acetonitrile extract group showed 0.1 × 106 ± 0.07 L5178Y cells (P < .05). The oral SF-A group showed 12.9 × 106 ± 243 L5178Y cells, and intraperitoneal (i.p.)-treated SF-A group showed 0.1 × 106 ± 0.05 L5178Y cells (P < .05) without any ascites volume development. The acetonitrile extract contains abundant polyphenols and possibly a flavone with antioxidant activity. The SF-A contains abundant alkamides. Both extracts are complexes and the identity of the compounds responsible for observed antitumor activity remains unknown.

Endosulfan decreases cytotoxic activity of nonspecific cytotoxic cells and expression of granzyme gene in Oreochromis niloticus.

The effect of the organochlorinated insecticide endosulfan, on the cytotoxic activity of Nile tilapia nonspecific cytotoxic cells (NCC) was assessed. Juvenile Nile tilapia were exposed to endosulfan (7 ppb) for 96 h and splenic NCC were isolated. Flow cytometric phenotyping of NCC was based on the detection of the NCC specific membrane signaling protein NCCRP-1 by using the monoclonal antibody Mab 5C6; granzyme expression was evaluated by quantitative RT-PCR. The cytotoxic activity of sorted NCC on HL-60 tumoral cells was assessed using propidium iodide (PI) staining of DNA in HL-60 nuclei, indicating dead cells. Nile tilapia splenic NCC had the ability to kill HL-60 tumoral cells, however, the exposure to endosulfan significantly reduced, by a 65%, their cytotoxic activity when using the effector:target ratio of 40:1. Additionally, the exposure to endosulfan tended to increase the expression of NCCRP-1, which is involved in NCC antigen recognition and signaling. Moreover, it decreased the expression of the granzyme gene in exposed group as compared with non-exposed group; however significant differences between groups were not detected. In summary, the acute exposure of Nile tilapia to sublethal concentration of endosulfan induces alteration in function of NCC: significant decrease of cytotoxic activity and a tendency to lower granzyme expression, severe enough to compromise the immunity of this species.