Ozonized vegetable oils are gaining attention for their antimicrobial and therapeutic potential, yet the lack of standardized ozonation protocols and incomplete characterization of their chemical profiles hinder clinical translation. In this study, we standardized the ozonation process of sunflower oil and investigated the chemical evolution and antimicrobial efficacy of the resulting products. Ozonation proceeded through a classical three-step mechanism involving the formation of primary ozonides, their decomposition into carbonyl compounds and carbonyl oxides, and subsequent recombination into stable secondary ozonides capable of sustained ozone release with reduced toxicity. Time-course analysis at 100, 240, and 480 min revealed key reaction products, including the appearance of azelaic acid after 240 min, progressive depletion of linoleic acid, and the emergence of 2,5-furandione exclusively after 480 min—indicative of advanced oxidative processes. The formation of hydroperoxides and their secondary degradation into ketones, acids, and epoxides was also observed, with implications for both biological activity and sensory properties. Importantly, the ozonized oil demonstrated potent antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella choleraesuis, Pseudomonas aeruginosa, Candida albicans, and Aspergillus brasiliensis. These findings provide a comprehensive chemical and functional characterization of ozonized sunflower oil and support its development as a standardized antimicrobial agent for therapeutic use.

Background/Objectives: Calcium hydroxyapatite (CaHA)-based injectable materials are widely used as dermal biostimulators. In vitro models allow for controlled comparison of cellular responses and particle characteristics across formulations. This study aimed to compare two commercially available CaHA-based materials in terms of fibroblast metabolic activity, extracellular matrix-related gene expression, and microsphere morphology. Methods: Primary human dermal fibroblasts were exposed to two CaHA-based materials (Sample R and Sample S) at 10 mg/mL. Metabolic activity was assessed using the MTT assay at 24, 36, 48, and 72 h. Type I collagen and elastin gene expression were evaluated by RT-qPCR at 72 h. Microsphere morphology was analyzed by scanning electron microscopy (SEM). Results: Both materials increased fibroblast metabolic activity compared with the control at all time points. Early responses were similar, whereas Sample S showed higher activity at 48 and 72 h. At 72 h, both materials increased collagen and elastin gene expression versus the control, with greater responses observed for Sample S. SEM analysis showed predominantly spherical microspheres in both materials, with qualitative differences in surface microtopography. Conclusions: Under controlled in vitro conditions, both CaHA-based materials were biocompatible and modulated fibroblast metabolic activity and extracellular matrix-related gene expression. Differences in particle surface characteristics may contribute to the observed biological profiles. These findings support further studies incorporating extended incubation periods and protein-level analyses.

Background/Objectives: Depletion of nicotinamide adenine dinucleotide (NAD⁺) impairs dermal fibroblast function and accelerates skin aging. NAD⁺ precursors such as nicotinamide mononucleotide (NMN) and the reduced form, NADH, are therefore candidate cosmetic actives, but their comparative and combined effects in skin cells remain poorly explored. This in vitro study compared NMN alone, NADH alone, and an NMN + NADH co-formulation. Methods: Human dermal fibroblasts (HDFs) and human mesenchymal stromal cells (hMSCs) were treated with 10 mg/mL of NMN, NADH, or NMN + NADH. Expression of FOXO3, SIRT1, and SIRT3 (HDFs) and NRF2, NOG, and WNT5A (hMSCs) was measured by RT-qPCR, and cellular senescence was quantified by β-galactosidase staining. Results: All treatments increased gene expression relative to untreated controls (p < 0.05), except WNT5A in NMN-treated hMSCs. Increases ranged from 15.4% to 52.3% with NMN, 22.3% to 60.7% with NADH, and 30.5% to 78.1% with NMN + NADH. The co-formulation produced the highest mean expression in every panel and was significantly higher than both single compounds for FOXO3, NRF2, NOG, and WNT5A and higher than NMN for SIRT1; NADH exceeded NMN for NRF2 and WNT5A. The proportion of β-galactosidase-positive HDFs fell from 15.6% in controls to 4.8% (NMN), 3.4% (NADH), and 3.0% (NMN + NADH) (p < 0.01), with no significant differences among treatments. Conclusions: NMN, NADH, and their co-formulation each reduced senescence and modulated longevity-, antioxidant-, and tissue-homeostasis-related genes, with the co-formulation showing the largest transcriptional effects. Because the amount of each active differed between the single compounds and the co-formulation, additive, synergistic, and dose-related effects cannot be distinguished.

Background/Objectives: Calcium hydroxylapatite (CaHA) is widely used in aesthetic medicine as a biostimulatory dermal filler. While its ability to induce neocollagenesis is well established, its broader transcript-level effects on fibroblast biology under aging-like conditions remain incompletely characterized. This study aimed to compare the gene-expression responses induced by three commercially available CaHA formulations in an EX-527-induced aging-like human dermal fibroblast model. Methods: An aging-like fibroblast phenotype was induced in primary human dermal fibroblasts using the SIRT1 inhibitor EX-527, which was maintained in culture throughout the CaHA treatment period. Cells were exposed to three commercially available CaHA formulations (D, R, S) for 72 h. Gene expression was assessed by RT-qPCR, evaluating markers related to extracellular matrix remodeling, Ki67 expression, inflammatory and regulatory cytokine signaling, mitochondrial stress response and energy metabolism, and longevity-associated genes. Results: All CaHA formulations induced upregulation of COL1A1 and Ki67, with greater responses observed in samples S and R. ELN expression was more selectively increased, particularly in sample S. Distinct cytokine gene-expression profiles were observed, with sample D associated with increased TNF-α expression, while samples R and S demonstrated reduced TNF-α and increased IL-10 expression. Genes associated with mitochondrial stress response and energy metabolism, including PGC-1α, SOD2, and PINK1, were upregulated across groups, with the highest induction generally observed in sample S. FOXO3, SIRT1, and SIRT3 expression also increased following treatment, with sample S showing the most pronounced response for FOXO3 and SIRT3. Conclusions: These transcript-level findings suggest that CaHA exposure is associated with differential gene-expression responses involving markers related to extracellular matrix remodeling, inflammatory and regulatory signaling, mitochondrial stress response, and longevity-associated pathways. Functional and protein-level validation will be required to determine whether these transcriptional changes translate into meaningful biological effects in more complex models of aging skin.