Efstathia Ioannou

Over the last decades, soft corals have been proven a rich source of biologically active compounds, featuring a wide range of chemical structures. Herein, we investigated the chemistry of an alcyonarian of the genus Lemnalia (Neptheidae), specimens of which were collected from the coral reefs near Al Lith, on the south‐west coast of Saudi Arabia. A series of chromatographic separations led to the isolation of 31 sesquiterpenes, featuring mainly the nardosinane and neolemnane carbon skeletons, among which three ( 13 , 14 and 28 ) are new natural products. The metabolites isolated in sufficient amounts were evaluated in vitro in human tumor and non‐cancerous cell lines for a number of biological activities, including their cytotoxic, anti‐inflammatory, anti‐angiogenic, and neuroprotective activities, as well as for their effect on androgen receptor (AR)‐regulated transcription. Among the tested metabolites, compound 12 showed comparable neuroprotective activity to the positive control N ‐acetylcysteine, albeit at a 10‐fold lower concentration.

Periodontitis is a microbially-induced inflammation of the periodontium that is characterized by the destruction of the periodontal ligament (PDL) and alveolar bone and constitutes the principal cause of teeth loss in adults. Periodontal tissue regeneration can be achieved through guided tissue/bone regeneration (GTR/GBR) membranes that act as a physical barrier preventing epithelial infiltration and providing adequate time and space for PDL cells and osteoblasts to proliferate into the affected area. Electrospun nanofibrous scaffolds, simulating the natural architecture of the extracellular matrix (ECM), have attracted increasing attention in periodontal tissue engineering. Carrageenans are ideal candidates for the development of novel nanofibrous GTR/GBR membranes, since previous studies have highlighted the potential of carrageenans for bone regeneration by promoting the attachment and proliferation of osteoblasts. Herein, we report the development of bi- and tri-layer nanofibrous GTR/GBR membranes based on carrageenans and other biocompatible polymers for the regeneration of periodontal tissue. The fabricated membranes were morphologically characterized, and their thermal and mechanical properties were determined. Their periodontal tissue regeneration potential was investigated through the evaluation of cell attachment, biocompatibility, and osteogenic differentiation of human PDL cells seeded on the prepared membranes.