Peroxisome proliferator-activated receptor-γ (PPARγ) has been reported to be involved in the etiology of pathological features of Alzheimer's disease (AD). Cannabidiol (CBD), a Cannabis derivative devoid of psychomimetic effects, has attracted much attention because of its promising neuroprotective properties in rat AD models, even though the mechanism responsible for such actions remains unknown. This study was aimed at exploring whether CBD effects could be subordinate to its activity at PPARγ, which has been recently indicated as its putative binding site. CBD actions on β-amyloid-induced neurotoxicity in rat AD models, either in presence or absence of PPAR antagonists were investigated. Results showed that the blockade of PPARγ was able to significantly blunt CBD effects on reactive gliosis and subsequently on neuronal damage. Moreover, due to its interaction at PPARγ, CBD was observed to stimulate hippocampal neurogenesis. All these findings report the inescapable role of this receptor in mediating CBD actions, here reported.

A review is presented of the literature data concerning the effects induced by carbon nanoparticles on the biological environment and the importance of these effects in human and animal health. The discovery in 1985 of fullerenes, a novel carbon allotrope with a polygonal structure made up solely by 60 carbon atoms, and in 1991 of carbon nanotubes, thin carbon filaments (1-3 microm in length and 1-3 nm in diameter) with extraordinary mechanical properties, opened a wide field of activity in carbon research. During the last few years, practical applications of fullerenes as biological as well as pharmacological agents have been investigated. Various fullerene-based compounds were tested for biological activity, including antiviral, antioxidant, and chemiotactic activities. Nanotubes consist of carbon atoms arranged spirally to form concentric cylinders, that are perfect crystals and thinner than graphite whiskers. They are stronger than steel but very flexible and lightweight and transfer heat better than any other known material. These characteristics make them suitable for various potential applications such as super strong cables and tips for scanning probe microscopes, as well as biomedical devices for drug delivery, medical diagnostic, and therapeutic applications. The effects induced by these nanostructures on rat lung tissues, as well as on human skin and human macrophage and keratinocyte cells are presented.

Preincubation of rabbit platelet-rich plasma with cocaine hydrochloride, at low and high concentrations, increased the platelet responsiveness to arachidonic acid, in terms of the aggregating response and the thromboxane production. The thromboxane levels released by collagen-stimulated platelets were increased after incubation with low concentrations of cocaine, while marked decreases were observed after incubation with high doses of cocaine. No effects on platelet aggregation induced by collagen and ADP were observed when low concentrations of cocaine were added; on the other hand, high doses of the anaesthetic were found to block the aggregating effects of these two agents. Specific studies showed cocaine to have an inhibitory activity on prostacyclin release when the aortic tissue was mechanically and thermically stimulated. By contrast, the prostacyclin synthesis by ‘exhausted’ aortic rings incubated with arachidonic acid appeared to be enhanced after addition of cocaine. These results lead us to believe that cocaine modifies both the Ca⁺⁺ membrane binding and the extent of Ca⁺⁺ influx, thereby increasing the permeability to arachidonic acid and altering the affinity of the membrane binding sites for the aggregating agents.

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Self-assembling gelling peptides are increasingly being investigated as defined biomatrices for biomedical applications. Using an enzymatic reaction to convert a precursor into a hydrogelator one can control or modulate functions and responses of a hydrogel, depending on its preparation conditions. This work details the self-assembly, under physiological conditions, of amphiphilic building blocks consisting of tripeptides (Phe(3)) linked to fluorenylmethoxycarbonyl (Fmoc) obtained by using a lipase to link an Fmoc-Phe amino acid to the dipeptide diphenylalanine (Phe(2)). The viscoelastic properties of the tripeptides obtained were investigated. SEM and AFM images of Fmoc- peptides confirmed that they self-assemble to generate supramolecular aggregates driven by pi-pi stacking interactions of the Fmoc groups