Search Results (4)

This study portrays macroalgal assemblage structure in the transitional water system Mar Piccolo of Taranto (eLTER site) from 2012 to 2023, assessing the impact of the establishment of non-indigenous species (NIS). Seasonal sampling at three sites evaluated diversity and biomass variation through PERMANOVA, PCoA, PERMDISP and Indicator Value (IndVal) analyses. Results reveal significant spatio-temporal heterogeneity: Site 1 remains dominated by native species (>70% biomass) and summer peaks of NIS (>70% biomass) were recorded at Site 3, whereas Site 4 experienced a substantial NIS expansion, reaching 97% of the total biomass by 2021. Statistical clustering identified distinct indicator species for each inlet of the basin, such as Amphiroa beauvoisii (IndVal = 100) in the First Inlet and the NIS Hypnea corona (IndVal = 65.6) in the Second. Water temperature emerged as a primary driver of community shifts. Most species, including both native (Chondracanthus acicularis; r_s = 0.50, p ≤ 0.05) and several NIS (Polysiphonia morrowii r_s = 0.65, p ≤ 0.5; Osmundea oederi r_s = 0.70, p ≤ 0.5), exhibited negative correlations with mean thermal values, while Ulva laetevirens (r_s = −0.50, p ≤ 0.05) showed greater tolerance. These findings highlight the importance of LTER monitoring in demonstrating that the Mar Piccolo’s resistance to NIS pressure is non-uniform across the basin. Under a global warming scenario, thermal forcing is actively reshaping macroalgal assemblages. Full article

Polysiphonia morrowii is a well-known red alga that has promising pharmacological characteristics. The current study evaluates the protective effect of 3-bromo-4,5-dihydroxybenzaldehyde (BDB) isolated from P. morrowii on tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated inflammation and skin barrier deterioration in HaCaT keratinocytes. The anti-inflammatory effect of BDB in TNF-α/IFN-γ-stimulated HaCaT keratinocytes is evaluated by investigating nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways, inflammatory cytokines, and chemokines. Further, the interaction between BDB and the skin barrier functions in stimulated HaCaT keratinocytes is investigated. The findings of the study reveal that BDB dose-dependently increases cell viability while decreasing intracellular reactive oxygen species (ROS) production. BDB downregulates the expression of inflammatory cytokines, interleukin (IL)-6, -8, -13, IFN-γ, TNF-α, and chemokines, Eotaxin, macrophage-derived chemokine (MDC), regulated on activation, normal T cells expressed and secreted (RANTES), and thymus and activation-regulated chemokine (TARC) by modulating the MAPK and NF-κB signaling pathways in TNF-α/IFN-γ-stimulated HaCaT keratinocytes. Furthermore, BDB increases the production of skin hydration proteins and tight junction proteins in stimulated HaCaT keratinocytes by preserving skin moisturization and tight junction stability. These findings imply that BDB exhibits a protective ability against inflammation and deterioration of skin barrier via suppressing the expression of inflammatory signaling in TNF-α/IFN-γ-stimulated HaCaT keratinocytes. Full article

In this study, we investigated the anti-allergic effects of 3,4-dihydroxybenzaldehyde (DHB) isolated from the marine red alga, Polysiphonia morrowii, in mouse bone-marrow-derived cultured mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) in anti-dinitrophenyl (DNP) immunoglobulin E (IgE)-sensitized mice. DHB inhibited IgE/bovine serum albumin (BSA)-induced BMCMCs degranulation by reducing the release of β-hexosaminidase without inducing cytotoxicity. Further, DHB dose-dependently decreased the IgE binding and high-affinity IgE receptor (FcεRI) expression and FcεRI-IgE binding on the surface of BMCMCs. Moreover, DHB suppressed the secretion and/or the expression of the allergic cytokines, interleukin (IL)-4, IL-5, IL-6, IL-13, and tumor necrosis factor (TNF)-α, and the chemokine, thymus activation-regulated chemokine (TARC), by regulating the phosphorylation of IκBα and the translocation of cytoplasmic NF-κB into the nucleus. Furthermore, DHB attenuated the passive cutaneous anaphylactic (PCA) reaction reducing the exuded Evans blue amount in the mouse ear stimulated by IgE/BSA. These results suggest that DHB is a potential therapeutic candidate for the prevention and treatment of type I allergic disorders. Full article