Maria Rachele Ceccarini

The journal retracts the article titled “Neutral Sphingomyelinase Modulation in the Protective/Preventive Role of rMnSOD from Radiation-Induced Damage in the Brain”

Background/Objectives: Extracellular Vesicles (EVs) have shown great promise as diagnostic and therapeutic tools, as well as pharmacological nanocarriers. Various strategies are being explored to develop EVs for monitoring, imaging, loading with pharmacological agents, and surface decoration with tissue-specific ligands. EVs derived from Mesenchymal Stromal Cells (MSC-EVs) are of particular interest both as therapeutics per se and as natural nanocarriers for the targeted delivery of biotherapeutics. Methods: In this study, we investigated the ability of different tags to deliver a reporter protein into canine MSC-EVs with the aim of identifying the most effective endogenous loading mechanism. To this aim, canine MSCs were engineered to express the Green Fluorescent Protein (GFP) fused to CD63, Syntenin-1, TSG101, and the palmitoylation signal of Lck, which were expected to promote GFP incorporation into EVs. Overexpression of tagged GFP in canine MSCs was confirmed by Western blotting and examined by confocal microscopy and transmission electron microscopy to map intracellular localization. Results: All tags were able to deliver GFP into EVs. Syntenin-1 showed relatively high loading efficiency and secretion index but exhibited a diffuse localization pattern in the transfected cells. The palmitoylation signal showed low loading efficiency and localization specificity. TSG101 displayed a morphological pattern consistent with specific localization in endosomal structures, but its low expression level prevented further evaluations. Finally, CD63 showed the highest expression efficiency, as GFP-CD63 levels were approximately 5-fold higher than untagged GFP. Conclusions: In conclusion, CD63 emerged as the most suitable tag for canine MSC-EV engineering. Indeed, even if the secretion index favours Syntenin-1, CD63’s higher abundance in the lysate suggests its substantial post-secretion uptake. Further studies aimed at elucidating CD63’s specific contribution and identifying the domains involved in vesicle trafficking could provide valuable insights into EV bioengineering.

Background/Objectives: Extracellular Vesicles (EVs) have shown promise as diagnostic and therapeutic tools as well as pharmacological nanocarriers. Strategies are being explored to develop EVs to enable their monitoring, imaging, loading with pharmacological agents and surface decoration with tissue-specific ligands. EVs derived from mesenchymal stromal cells (MSC-EVs) are of interest both as therapeutics per se and as natural nanocarriers for the targeted delivery of biotherapeutics. Methods: In this study, we investigated the ability of different tags to deliver a reporter protein into canine MSC-EVs with the aim of identifying the most effective endogenous loading mechanism. To this end, canine MSCs were engineered to express the green fluorescent protein (GFP) associated with CD63, syntenin-1, TSG101 and the palmitoylation signal of Lck, which were expected to introduce GFP into EVs. Overexpression of tagged GFP in canine MSCs was detected by Western blotting and examined by confocal and transmission electron microscopy to map intracellular localization. Results: All tags were able to deliver GFP into EVs. Syntenin-1 showed high efficiency but exhibited a diffuse localization pattern in the transfected cells. Palmitoylation signal showed low efficiency and low specificity in terms of localization. TSG101 showed a morphological pattern consistent with a specific localization in endosomal structures, but its low expression did not allow further considerations. Finally, CD63 showed the highest expression efficiency, as GFP-CD63 was 5-fold higher than untagged GFP. Conclusions: In conclusion, CD63 is the most effective tag for canine MSC-EVs engineering. Further studies aimed at better deciphering its contribution and clarifying which part of the molecule is involved in vesicle trafficking could provide insights for EV bioengineering.

Storage conditions significantly impact the quality and functional properties of extra-virgin olive oil (EVOO). This study investigated the impact of light and dark storage on the nutritional quality of Umbrian EVOO and its effectiveness in tissue repair. The research aimed to simulate real-world conditions occurring during transport, retail, and domestic storage. Light exposure accelerated EVOO oxidation, significantly affecting peroxide levels (ranging from 5.19 to 24.30 meq O₂/kg of oil), total antioxidant capacity (measured spectrophotometrically, collectively ranging from 399.47 to 684.63 mg TE/kg of oil), and phenolic compound concentrations, particularly secoiridoids, lignans, and flavonoids (measured by HPLC, collectively ranging from 41.92 to 169.74 mg/kg of oil). Statistically significant differences (p < 0.01) were recorded between the control sample and the others in almost all cases, after storage. For instance, both light and dark exposure over a 24-month period resulted in a marked reduction (p < 0.01) in oleocanthal, pinoresinol, luteolin, and apigenin. Pigment levels were also affected, representing a rapid and cost-effective indicator of product oxidative degradation. The loss of phenolic compounds (especially oleacein and oleocanthal, which showed the most significant reductions of approximately 75% and 60%, respectively), impaired the EVOO’s wound-healing properties, affecting key tissue regeneration processes such as keratinocyte migration, hyaluronic acid synthesis, and angiogenesis. Notably, oleocanthal and oleacein, present at higher concentrations in fresh extracts, emerged as the primary contributors to the observed dermal effects and wound-healing processes, demonstrating a significant highest efficacy (p < 0.0001) in promoting wound closure. These findings underscore the critical role of EVOO storage in preserving its sensory properties and labile components with tissue repair and regeneration functions.

In this study, we report the preparation and characterization of water-stable films with UV-shielding and good mechanical properties, exploiting the synergistic effect of regenerated silk fibroin and bamboo-derived cellulose. Silk fibroin (SF)/bamboo (B) hybrid films are achieved by solubilizing both silk and bamboo fibers in formic acid with added CaCl₂. Infrared spectroscopy indicates that SF, when combined with bamboo, undergoes a conformational transition, providing evidence of an increase in SF crystallinity. Exploiting the intrinsic absorption of SF in the ultraviolet region, UV–Vis spectroscopy was used to assess the glass transition temperature (T_g) of SF/B films, showing a decrease in T_g by increasing the SF content. The addition of 10 wt% SF to the B matrix improved the elastic modulus by about 10% while conserving the strain at break with respect to the neat B films, increasing the UV shielding properties, while water absorption suggested the material’s hydrophilic and swelling capacity even after one month. The hybrid films showed, under solar irradiation, a photoprotective behavior on keratinocyte human cells by increasing cellular viability. These findings may find potential applications in functional fabrics.

The role of sphingomyelin metabolism and vitamin C in cancer has been widely described with conflicting results ranging from a total absence of effect to possible preventive and/or protective effects. The aim of this study was to establish the possible involvement of sphingomyelin metabolism in the changes induced by vitamin C in breast cancer cells. The MCF7 cell line reproducing luminal A breast cancer and the MDA-MB-231 cell line reproducing triple-negative breast cancer were used. Cell phenotype was tested by estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 expression, and proliferation index percentage. Sphingomyelin was localized by an EGFP-NT-Lys fluorescent probe. Sphingomyelin metabolism was analyzed by RT-PCR, Western blotting and UFLC-MS/MS. The results showed that a high dose of vitamin C produced reduced cell viability, modulated cell cycle related genes, and changed the cell phenotype with estrogen receptor downregulation in MCF7 cell. In these cells, the catabolism of sphingomyelin was promoted with a large increase in ceramide content. No changes in viability and molecular expression were observed in MB231 cells. In conclusion, a high dose of vitamin C induces changes in the luminal A cell line involving sphingomyelin metabolism.

Goji berry (GB) shows beneficial effects on human health, although its effects on the male rabbit have been little investigated. This study examines the impact of GB dietary supplementation on the semen traits, antioxidant capacity of seminal plasma, and histological features of the reproductive tract of rabbit buck. Eighteen rabbits were distributed into two dietary groups: one receiving a commercial feed (Control), and the other a feed supplemented with 1% of GB (Goji). After a nutritional adaptation period of 60 days, the animals were subjected to semen collection every 15 days. The semen traits, libido, antioxidant, and inflammatory parameters were collected and analyzed. The rabbits were sacrificed after 60 days, and tissues of the genital tract were analyzed. Compared to the Control group, the Goji group showed higher spermatozoa concentration, motility, and vitality (p < 0.05), as well as fewer abnormal spermatozoa and a higher libido (p < 0.1). Histological features such as functional activity and hyperplasia were improved by GB and correlated with some semen traits (p < 0.05). Conversely, antioxidant and anti-inflammatory parameters were unaffected by the diet. These findings suggest that GB acts on the tissues of the reproductive tract positively influencing semen quality, although further studies are needed to understand the effect on oxidative stress.