Genotoxic and Mutagenic Activity of PT-31.

Toxicity assessment is an important tool in drug discovery and development. PT-31 (3-(2-chloro-6-fluorobenzyl)-imidazolidine-2,4-dione) is an imidazolidine- 2,4-dione analogue of clonidine that displays a dose-dependent analgesic profile and synergism with morphine. This study investigated genotoxic and mutagenic effects of PT-31 in Swiss mice. For this, ten mice (M1:F1) per group were treated with PT-31 intraperitoneally (i.p.) at 0.5, 1.0 and 5.0 mg/kg. The dimethyl sulfoxide (0.5%) and 50 mg/kg cyclophosphamide (i.p.) were taken as negative (NC) and positive controls, respectively. The bone marrow cells were collected after 24 h, while peripheral blood after 30 min, 12 h and 24 h of the treatment for the comet assay. Micronucleus (MN) test was performed only on bone marrow cells collected after 24 h of i.p. treated animals. A hundred cells were considered for the comet assay and quantification of the index of damage and frequency of damage. Lack of genotoxicity with 0.5 mg/kg of PT-31 and DNA repair ability with 0.5 and 1.0 mg/kg doses at 12 h and 24 h in comparison to NC group was observed (P<0.05). There was an increase in MN formation by PT-31 1.0 and 5.0 mg/kg treated female and male mice, respectively. PT-31 induced genotoxic and mutagenic effects only in higher doses.

Phytol, a diterpene alcohol from chlorophyll, as a drug against neglected tropical disease Schistosomiasis mansoni.

BACKGROUND: Schistosomiasis is a major endemic disease that affects hundreds of millions worldwide. Since the treatment and control of this parasitic disease rely on a single drug, praziquantel, it is imperative that new effective drugs are developed. Here, we report that phytol, a diterpene alcohol from chlorophyll widely used as a food additive and in medicinal fields, possesses promising antischistosomal properties in vitro and in a mouse model of schistosomiasis mansoni. METHODS AND FINDINGS: In vitro, phytol reduced the motor activity of worms, caused their death and confocal laser scanning microscopy analysis showed extensive tegumental alterations in a concentration-dependent manner (50 to 100 µg/mL). Additionally, phytol at sublethal doses (25 µg/mL) reduced the number of Schistosoma mansoni eggs. In vivo, a single dose of phytol (40 mg/kg) administered orally to mice infected with adult S. mansoni resulted in total and female worm burden reductions of 51.2% and 70.3%, respectively. Moreover, phytol reduced the number of eggs in faeces (76.6%) and the frequency of immature eggs (oogram pattern) was significantly reduced. The oogram also showed increases in the proportion of dead eggs. Confocal microcopy studies revealed tegumental damage in adult S. mansoni recovered from mice, especially in female worms. CONCLUSIONS: The significant reduction in parasite burden by this chlorophyll molecule validates phytol as a promising drug and offers the potential of a new direction for chemotherapy of human schistosomiasis. Phytol is a common food additive and nonmutagenic, with satisfactory safety. Thus, phytol has potential as a safe and cost-effective addition to antischistosomal therapy.