Tail breakage and predatory pressure upon two invasive snakes (Serpentes: Colubridae) at two islands in the Western Mediterranean

Tail breakage is an important anti-predator mechanism in snake populations, which can be used as a proxy for predation intensity as natural observations of predator-prey interactions are scarce. Frequency of tail breakage was calculated for two Iberian colubrids recently introduced in the Balearic Islands (Western Mediterranean, Spain): Hemorrhois hippocrepis (Linnaeus, 1758) in Eivissa and Zamenis scalaris (Schinz, 1812) in Formentera. The effect of sex, life-stage, dorsal coloration pattern, body length and body condition on frequency of tail breakage and on remaining subcaudal scale pairs (SBC) were analyzed and compared between the native range and the invaded islands. An increase of the frequency of tail breakage with body size was found, supporting a size-related effect, which also occurs in the native range. Frequency of tail breakage of H. hippocrepis was lower in Eivissa when compared with the original area, while in Formentera Z. scalaris showed a higher frequency, which could be related to the different predator community on each island compared with the mainland. The study of the main ecological aspects of these recent introduced species may allow to assess their potential impact on insular ecosystems and their native biodiversity as well as to promote future control actions in these areas previously free of snakes.

Targeting NF-κB signaling pathway in cancer by dietary polyphenols

Being a transcription factor, NF-κB regulates gene expressions involving cell survival and proliferation, drug resistance, metastasis, and angiogenesis. The activation of NF-κB plays a central role in the development of inflammation and cancer. Thus, the down-regulation of NF-κB may be an exciting target in prevention and treatment of cancer. NF-κB could act as a tumor activator or tumor suppressant decided by the site of action (organ). Polyphenols are widely distributed in plant species, consumption of which have been documented to negatively regulate the NF-κB signaling pathway. They depress the phosphorylation of kinases, inhibit NF-κB translocate into the nucleus as well as interfere interactions between NF-κB and DNA. Through inhibition of NF-κB, polyphenols downregulate inflammatory cascade, induce apoptosis and decrease cell proliferation and metastasis. This review highlights the anticancer effects of polyphenols on the basis of NF-κB signaling pathway regulation.

Changes in circulating cytokines and markers of muscle damage in elite cyclists during a multi-stage competition

The purpose of this study was to determine the changes in the basal and post-exercise plasma markers of muscular damage, lipid peroxidation and cytokines in eight male well-trained semiprofessional cyclists, in response to a three consecutive-day cycling competition. Serum markers of oxidative and muscular damage - creatine kinase activity, lactate dehydrogenase activity, myoglobin and malondialdehyde (MDA), creatinine and nitrite levels - followed a sawtooth-type representation throughout the competition. MDA showed an accumulative pattern, evidenced in the post-race values of the third stage which were significantly higher with respect to the values of the first stage. Cortisol levels were significantly influenced by an interaction between the exercise and the stage factors, with higher values on the 4th day. Plasma cytokine levels were only determined before the first stage and post-race, after the third stage. The exercise increased TNFα, IL6, IL2 and IFNγ levels, whereas IL1β was unchanged. In conclusion, cyclist stages induced oxidative and cellular muscle damage which is partially recovered to basal values by the next morning. Repetitive stages during the cycling competition accumulated plasma muscular damage and lipid peroxidation markers and pro-inflammatory cytokines, probably as a result of local inflammatory responses.