Exercise intensity usually correlates with increased oxidative stress and enhanced cytokine production. However, it is unknown if all types of exercise that induce muscle damage can cause a parallel response in the oxidation balance and cytokine production. To this end, the effect of a 2000-m running test in a group of volunteers that regularly train in aerobic routines was studied. Different circulating parameters were measured, oxidative stress markers (protein carbonyls and malondialdehyde), antioxidant enzyme activity, and cytokine levels in plasma as well as in the main circulating cells of blood samples obtained in basal conditions and after test execution. As a result, the test caused muscle damage evidenced by an increase in circulating creatine kinase and myoglobin. This was accompanied by an increase in protein carbonyls in plasma and peripheral blood mononuclear cells. Activities of antioxidant enzymes (catalase, glutathione peroxidase and reductase, superoxide dismutase) were elevated in peripheral blood mononuclear cells, neutrophils, and erythrocytes after the test. Regarding cytokine production, interleukin-6, interleukin-8, interleukin-10, and tumor necrosis factor-α exhibited no significant changes after the test. Results suggest that this short but intense running exercise (2000 m) can induce muscle damage and elicit a good balance between oxidant/antioxidant responses with no changes in the circulating concentration of pro-inflammatory cytokines.

Cationic polypeptides and cationic polymers have cell-penetrating capacities and have been used in gene transfer studies. In this study, we investigate the capability of a polymer of D-lysine (PDL), a chiral form of α-Poly-lysine, as a possible nonviral vector for releasing genetic materials to neuroblastoma cells and evaluate its stability against proteases. We tested and compared its transfection effectiveness in vitro as a vehicle for the EGFP plasmid DNA (pDNA) reporter in the SH-SY5Y human neuroblastoma, HeLa, and 3T3 cell lines. Using fluorescent microscopy and flow cytometry, we demonstrated high transfection efficiencies based on EGFP fluorescence in SH-SY5Y cells, compared with HeLa and 3T3. Our results reveal PDL as an efficient vector for gene delivery specifically in the SH-SY5Y cell line and suggest that PDL can be used as a synthetic cell-penetrating polypeptide for gene therapy in neuroblastoma cells.

The synthesis and characterization of two new water soluble 2,6-bis(imidazolylmethyl)-4-methylphenoxy-containing perylenediimides, PDI-1 and PDI-2, are described. These compounds demonstrate a high fluorescence quantum yield in water and were investigated as potential photosensitizers for generating reactive oxygen species with applications in anticancer activities. The HeLa cell line (VPH18) was used to evaluate their efficacy. Fluorescence microscopy was employed to confirm the successful internalization of PDI-1 and PDI-2, while confocal microscopy revealed the specific locations of both PDIs within the lysosomes and mitochondria. In vitro studies were conducted to evaluate the anticancer activity of PDI-1 and PDI-2. Remarkably, these photosensitizers demonstrated a significant ability to selectively eliminate cancer cells when exposed to a specific light wavelength. The water solubility, high fluorescence quantum yield, and selective cytotoxicity of these PDIs toward cancer cells highlight their potential as effective agents for targeted photodynamic therapy. In conclusion, the findings presented here provide a strong foundation for the future exploration and optimization of PDI-1 and PDI-2 as effective photosensitizers in photodynamic therapy, potentially leading to improved treatment strategies for cancer patients.