No abstract

No abstract

Caffeine has been reported for its antiinflammatory properties by stimulating phagocytosis. In this study, we investigated the antiinflammatory and antiinfective potential of caffeine in murine macrophage cell cultures and Swiss mice infected with virulent Salmonella enterica serotype typhimurium. Peritoneal macrophages (pMØ) were treated with caffeine on 96-well plates for 24 hr and then infected with Salmonella for 4 hr. In another experiment, the pMØ were first infected with the bacterium for 4 hr and then treated with caffeine for 24 hr. In addition, Swiss mice were inoculated, intraperitoneally, with S. typhimurium and then received caffeine intravenously. Control groups received phosphate-buffered saline (PBS) or dexamethasone. We found that treatments with caffeine increased the macrophage cell viability and reduced the intracellular bacterial load. The administration of caffeine to Swiss mice reduced the infiltration of leukocytes into the peritoneal cavity after the bacterial challenge.Furthermore, the bacterial burdens in the peritoneal fluid, bloodstream, spleen, and liver were decreased by caffeine treatment. The expression levels of tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), IL-6, and inducible nitric oxide synthase (iNOs) were down-regulated after infection in caffeine-treated mice. We can conclude that caffeine has both antiinflammatory and antiinfective properties that can be useful for management of bacterial infections along with antibiotics.

Cuba has a high biodiversity and many plants are widely known and used in folk medicine and for commercial manufacturing of phytomedicines. However, many plants have not been studied for their pharmacological properties, particularly endemic plants. Two simple, inexpensive and rapid biological assays, inhibition of germination of tomato and lettuce seeds and toxicity on the brine shrimp A. salina, have been evaluated as prescreens for possible antitumor activity. Extracts of six plant species collected in Havana, Cuba were subjected to the brine shrimp lethality test and inhibition of seed germination in order to detect potential sources of novel cytotoxic and cytostatic antitumor compounds, respectively. The larvicidal activity, based on the percentage of larval mortality, was evaluated after 24 h exposure to the treatments. In the case of inhibition of seed germination the readings were made 48 h after exposure. Semi-quantitative phytochemical prospecting was done by color and precipitation reactions for chemical functional groups. All species tested showed some cytotoxic and cytostatic effects. Two extracts showed high cytotoxicity in the Artemia salina test, the methanol extract from flowers of Tithonia diversifolia (TD) with IC50 (Inhibitory concentration 50) or LD50 (Lethal doses 50) of 1.14 µg/mL and methanol extract of stems from Castela lucida (CL) with LD50 of 0.052 µg/mL. However, the more promising species was the Tabebuia hypoleuca (TH) with cytostatic effect superior of 65% and good cytotoxic effect with the leaf extract, with the prominent compound classes’ triterpenes, tannins, phenols, and alkaloids. Keywords: Cuban plants; cytotoxic; Artemia salina; cytostatic; seed germination; chemical compounds