Giuseppe Carota

Nitric oxide (NO) plays an important role in neuronal communication, synaptic plasticity and vascular regulation. Due to its important function in neuronal homeostasis, NO imbalance is associated with neurodegeneration. Specifically, in Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson’s disease (PD) and frontotemporal lobar degeneration (FTLD), an excessive amount of NO, mostly produced by inducible NO synthase (iNOS), reacts with superoxide to form peroxynitrite, driving oxidative/nitrosative stress, mitochondrial dysfunction, and aberrant protein modifications. In AD, NO dysregulation promotes amyloid-β (Aβ) accumulation, tau hyperphosphorylation and synaptic loss, creating a self-perpetuating cycle of neuronal damage. NO’s dual role, protective at physiological levels but harmful if overproduced, underscores the therapeutic potential of antioxidant compounds that restore the balance of NO/NOS (especially iNOS) while preserving physiological functions. However, despite the emerging role of antioxidant-based therapeutic approaches, clinical translation is limited by the complexity of NO signaling and the absence of safe, specific NOS inhibitors. By targeting the molecular switch from protective to toxic, NO activity may offer new personalized treatment avenues for neurodegenerative diseases.

Combustion byproducts contained in cigarette smoke are considered the main responsible for the occurring of serious chronic diseases. Aerosols from electronic cigarettes contain substantially fewer of these dangerous byproducts, potentially reducing health risks. This study examined the potential of four different commercial nicotine-rich e-liquids to induce cytotoxicity and mitochondrial dysfunction and oxidative stress in human bronchial epithelial cells (H292), using air-liquid interface (ALI) exposure. In addition to a qualitative control of the e-liquids, by dosing contaminants, we assessed cell viability, apoptosis, mitochondrial membrane potential, and reactive oxygen species (ROS) generation, by comparing e-cig aerosols to 1R6F reference cigarette smoke. All tested e-liquids showed very low levels of trace metals and microplastics, with contaminant concentrations below WHO drinking water limits. Furthermore, e-liquid aerosol induced significantly reduced cytotoxicity compared to 1R6F regular cigarette smoke, and mitochondrial integrity was preserved. Furthermore, no ROS generation was observed when using flavored e-cigarette aerosol. These results provide evidence of the lower potential toxicity of e-cigarettes compared to tobacco cigarettes in an in vitro model simulating real-world smoke exposure.

Polyphenols are naturally occurring compounds that can be found in plant-based foods, including fruits, vegetables, nuts, seeds, herbs, spices, and beverages, the use of which has been linked to enhanced brain health and cognitive function. These natural molecules are broadly classified into two main groups: flavonoids and non-flavonoid polyphenols, the latter including phenolic acids, stilbenes, and tannins. Flavonoids are primarily known for their potent antioxidant properties, which help neutralize harmful reactive oxygen species (ROS) in the brain, thereby reducing oxidative stress, a key contributor to neurodegenerative diseases. In addition to their antioxidant effects, flavonoids have been shown to modulate inflammation, enhance neuronal survival, and support neurogenesis, all of which are critical for maintaining cognitive function. Phenolic acids possess strong antioxidant properties and are believed to protect brain cells from oxidative damage. Neuroprotective effects of these molecules can also depend on their ability to modulate signaling pathways associated with inflammation and neuronal apoptosis. Among polyphenols, hydroxycinnamic acids such as caffeic acid have been shown to enhance blood-brain barrier permeability, which may increase the delivery of other protective compounds to the brain. Another compound of interest is represented by resveratrol, a stilbene extensively studied for its potential neuroprotective properties related to its ability to activate the sirtuin pathway, a molecular signaling pathway involved in cellular stress response and aging. Lignans, on the other hand, have shown promise in reducing neuroinflammation and oxidative stress, which could help slow the progression of neurodegenerative diseases and cognitive decline. Polyphenols belonging to different subclasses, such as flavonoids, phenolic acids, stilbenes, and lignans, exert neuroprotective effects by regulating microglial activation, suppressing pro-inflammatory cytokines, and mitigating oxidative stress. These compounds act through multiple signaling pathways, including NF-κB, MAPK, and Nrf2, and they may also influence genetic regulation of inflammation and immune responses at brain level. Despite their potential for brain health and cognitive function, polyphenols are often characterized by low bioavailability, something that deserves attention when considering their therapeutic potential. Future translational studies are needed to better understand the right dosage, the overall diet, the correct target population, as well as ideal formulations allowing to overcome bioavailability limitations.

The intake of anthocyanins has been shown to have significant effects on the gut microbiota, influencing its composition, diversity, and functionality. These effects include promoting the growth of beneficial bacterial families, such as Bifidobacterium and Lactobacillus , and ameliorating microbiota diversity. The specific enzymes produced by these bacteria, such as β-glucosidases, hydrolases, and decarboxylases, are crucial for breaking down complex anthocyanin structures and converting them into bioactive molecules, able to cross the blood-brain barrier, potentially affecting brain health. As more research is needed into the specific roles of different microbial species on metabolites production, it becomes increasingly clear that the gut microbiota may play an important role in unlocking the potential health benefits of anthocyanins also in relation to brain health.

Background: There are challenges that require collaboration among researchers to ensure that tobacco harm reduction strategies are evidence-based. One key challenge is evaluating the safety of flavors used in electronic cigarettes (e-cigarettes). While many flavorings are approved as food additives or deemed “generally recognized as safe” (GRAS) for ingestion, this does not guarantee their safety when inhaled. In this context, the international research group Replica replicated a study conducted by Fetterman and colleagues in 2018, investigating the effects of aerosolized vanillin - one of the most popular flavors in vaping - on vascular endothelium when vaporized by an electronic cigarette. Methods: We used Aspire Zelos 3 e-cigarette and prepared e-liquids containing propylene glycol, vegetable glycerin and vanillin. The e-liquids were vaporized under two settings - regular (1 ohm coil using wattage control mode at 14 watts) and sub-ohm (0.3 ohm coil using temperature control mode at 200 °C) – using a vaping machine, following the standardized puffing regime, ISO20768:2018. The vapor was then collected into a trapping solution to prepare aqueous extracts for the treatment of human aortic endothelial cells. We evaluated cytotoxicity, oxidative stress, nitric oxide bioavailability, and inflammation addressing some gaps reported in the original study. Results: We observed some harmful effects, mostly attributable to ethanol, used to dilute vanillin in the original work by Fetterman, but no harmful effects on cell viability, their ability to produce nitric oxide, or oxidative stress from vanillin. Furthermore, no pro-inflammatory effects of vanillin were observed in terms of ICAM-1 and IL-6 gene expression. Conclusions: Our results confirm the endothelial cell dysfunction observed in the original paper, but clarify that these effects are mainly attributable to ethanol and not to vaporized vanillin. These findings suggest that vanillin could be a safer flavoring agent for e-cigarette, without causing adverse effects on the cardiovascular system.

The growing interest in natural bioactive molecules, as an approach to many pathological contexts, is widely justified by the necessity to overcome the disadvantageous benefit–risk ratio related to traditional therapies. Among them, mangiferin (MGF) shows promising beneficial properties such as antioxidant, anti-inflammatory, and immunomodulatory effects. In this study, we aimed to investigate the antioxidant and anti-inflammatory properties of MGF on lipopolysaccharide (LPS)-induced lung NCI-H292 cells, focusing on its role against COVID-19 adsorption. In order to obtain this information, cells treated with LPS, with or without MGF, were analyzed performing wound healing, gene expression of inflammatory cytokines, GSH quantification, and JC-1 staining. Moreover, the inhibition of viral adsorption was evaluated microbiologically and the results were further confirmed by molecular docking analysis. In this regard, MGF downregulates the expression of several inflammatory factors, enhances GSH levels, promotes the wound healing rate, and restores the mitochondrial dysfunction caused by LPS. In addition, MGF significantly inhibits SARS-CoV-2 adsorption as shown by the gene expression of ACE2 and TMPRSS-2, and furtherly confirmed by microbiological and molecular modeling evaluation. Although more investigations are still needed, all data obtained constitute a solid background, demonstrating the cytoprotective role of MGF in inflammatory mechanisms including COVID-19 infection.

Hemoglobin and iron overload is considered the major contributor to intracerebral hemorrhage (ICH)-induced brain injury. Accumulation of iron in the brain leads to microglia activation, inflammation and cell loss. Current available treatments for iron overload-mediated disorders are characterized by severe adverse effects, making such conditions an unmet clinical need. We assessed the potential of α-lipoic acid (ALA) as an iron chelator, antioxidant and anti-inflammatory agent in both in vitro and in vivo models of iron overload. ALA was found to revert iron-overload-induced toxicity in HMC3 microglia cell line, preventing cell apoptosis, reactive oxygen species generation and reducing glutathione depletion. Furthermore, ALA regulated gene expression of iron-related markers and inflammatory cytokines, such as IL-6, IL-1β and TNF. Iron toxicity also affects mitochondria fitness and biogenesis, impairments which were prevented by ALA pre-treatment in vitro. Immunocytochemistry assay showed that, although iron treatment caused inflammatory activation of microglia, ALA treatment resulted in increased ARG1 expression, suggesting it promoted an anti-inflammatory phenotype. We also assessed the effects of ALA in an in vivo zebrafish model of iron overload, showing that ALA treatment was able to reduce iron accumulation in the brain and reduced iron-mediated oxidative stress and inflammation. Our data support ALA as a novel approach for iron-overload-induced brain damage.

It is well recognized that functional foods rich in antioxidants and antiinflammation agents including polyphenols, probiotics/prebiotics, and bioactive compounds have been found to have positive effects on the aging process. In particular, fruits play an important role in regular diet, promoting good health and longevity. In this study, we investigated on biological properties of extract obtained from Mangifera indica L. leaves in preclinical in vitro models. Specifically, the profile and content of bioactive compounds, the antimicrobial potential toward food spoilage and pathogenic bacterial species, and the eventually protective effect in inflammation were examined. Our findings revealed that MLE was rich in polyphenols, showing a content exclusively in the subclass of benzophenone/xanthone metabolites, and these phytochemical compounds demonstrated the highest antioxidant capacity and greatest in vitro antibacterial activity toward different bacterial species such as Bacillus cereus, B. subtilis, Pseudomonas fluorescens, Staphylococcus aureus, and St. haemolyticus. Furthermore, our data showed an in vitro anti-inflammatory, antioxidant, and antifibrotic activity.