The green synthesis of silver (Ag) and zinc oxide (ZnO) nanoparticles (NPs), as well as Ag/Ag₂O/ZnO nanocomposites (NCs), using polar and apolar extracts of Chlorella vulgaris, offers a sustainable method for producing nanomaterials with tunable properties. The impact of the synthesis environment and the nanomaterials’ characteristics on cytotoxicity was evaluated by examining reactive species production and their effects on mitochondrial bioenergetic functions. Cytotoxicity assays on PC12 cells, a cell line originated from a rat pheochromocytoma, an adrenal medulla tumor, demonstrated that Ag/Ag₂O NPs synthesized with apolar (Ag/Ag₂O NPs A) and polar (Ag/Ag₂O NPs P) extracts exhibited significant cytotoxic effects, primarily driven by Ag⁺ ion release and the disruption of mitochondrial function. However, it is more likely the organic content, rather than size, influenced anticancer activity, as commercial Ag NPs, despite smaller crystallite sizes, exhibit less effective activity. ZnO NPs P showed increased reactive oxygen species (ROS) generation, correlated with higher cytotoxicity, while ZnO NPs A produced lower ROS levels, resulting in diminished cytotoxic effects. A comparative analysis revealed significant differences in LD₅₀ values and toxicity profiles. Differentiated PC12 cells showed higher resistance to ZnO, while AgNPs and Ag/Ag₂O-based materials had similar effects on both cell types. This study emphasizes the crucial role of the synthesis environment and bioactive compounds from C. vulgaris in modulating nanoparticle surface chemistry, ROS generation, and cytotoxicity. The results provide valuable insights for designing safer and more effective nanomaterials for biomedical applications, especially for targeting tumor-like cells, by exploring the relationships between nanoparticle size, polarity, capping agents, and nanocomposite structures.

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the leading cause of chronic liver disease, and liver-related morbidity and mortality worldwide. MASLD is a multifactorial condition, which still needs to be completely understood. Galectin 3 (Gal-3) is up-regulated in several liver disorders suggesting its implication in the mechanisms underlying liver damage. Methods: A human multilineage 3D model was utilized to investigate the role of Gal-3 in MASLD development. Human hepatoma cell line (HepG2) and human stellate cell line (LX-2) were co-cultured in a physiological ratio of 24:1 and treated with a mixture of palmitic and oleic acid (PAOA, ratio 1:2) to induce hepatocyte steatosis and facilitate the development of fibrosis. While the effect of LGALS3 silencing on neutral fat content was assessed by Oil-Red-O (ORO) staining, type I collagen production was analysed by immunofluorescent staining for collagen type I alpha 1 (COL1A1). Results: Gal-3 depletion caused a reduction of neutral lipid content and COL1A1 accumulation in 3D spheroids. While LGALS3 silencing did not significantly alter the respiratory state, analysis of genes involved in lipid metabolism demonstrated significant changes in genes involved in β-oxidation and triglyceride synthesis. Conclusion: These results suggest a role of Gal-3 in the regulation of fatty acid and collagen accumulation, thereby indicating that approaches aimed at inhibiting Gal-3 may represent a promising therapeutic strategy in MASLD.

Plastic compounds released into the environment can be accumulated in human tissues causing various health issues. It has been demonstrated that Bisphenol A (BPA), widely used in polycarbonate plastics and food packaging, can accumulate in gastrointestinal (GI) tract, inducing oxidative stress, metabolic dysfunction, and other cellular disturbances, including mitochondrial damage. However, the mechanisms by which BPA affects the GI function and affects mitochondrial function in the absorptive cells of the intestine, are still not completely understood. The aim of this study is to investigate whether BPA enters intact human intestinal cells and affects mitochondrial electron transport chain (ETC) function. High-resolution respirometry (O2k system, OROBOROS) and fluorometry were used to assess mitochondrial respiration and membrane potential (mt-MP) in Caco-2 cells under acute exposure to BPA. Cellular respiration was stimulated with complex I (C-I), II (C-II), IV (C-IV) and β-oxidation substrates in both intact and permeabilized Caco-2 cells. Morphological analysis of cells exposed to BPA was performed by electron microscopy. In intact cells, respiration rate decreased in presence of BPA, thus confirming the detrimental effects of BPA on ETC. In permeabilized cells, BPA caused a decrease of respiratory activity in presence of C-I and C-II substrates following a reduction of the ETC oxidative capacity and a depolarization of mt-MP. Morphological analysis suggested that BPA can be internalized by endocytosis. The reduced respiration rate in both intact and permeabilized cells indicates that BPA reaches mitochondria even without membrane permeabilization. BPA compromises both oxidative phosphorylation (OxPhos) and mt-MP, thus leading to an impairment of energy metabolism that could contribute to pathological alterations of the gastrointestinal function.