Ascorbic acid enhances bone parameter expression in human gingival mesenchymal stem cells.

Ascorbic acid (AS), also known as vitamin C or ascorbate, is an essential dietary nutrient which plays a vital role in biological processes through various different mechanisms, in particular for the biosynthesis of collagen. The aim of the study was to establish the possibility of enhancing the osteogenic differentiation potential by manipulating the cellular micro-environment, through AS supplementation in human gingival mesenchymal stem cells (hGMSCs) at different concentrations, such as 60 and 90 µg/mL, for three weeks. Human GMSCs are considered a stem cell population, easily obtainable and displaying a remarkable immunotherapeutic potential and regenerative repair expression. Osteogenic differentiation level induced from AS was assayed by histochemical characterization, using light microscopy through Alizarin red S staining. The transcript levels of Collagen 1A1 (COL1A1), runtrelated transcription factor 2 (RUNX2), bone morphogenetic protein 2/4 (BMP2/4), osteopontin (OPN) and osteonectin (SPARC) were determined by quantitative RT-PCR. Protein expression of COL1A1, RUNX2, BMP2/4, OPN, SPARC were studied through Western blotting and confocal laser scanning microscopy (CLSM). Our results demonstrate that AS supports osteogenic differentiation in stem cells from gingiva niche as shown by osteogenic marker upregulation and by de novo production of calcium phosphate deposits as revealed by Alizarin red S staining. In summary, the results of the current study provide evidence that hGMSCs undergo osteogenic differentiation with AS treatment, for that reason AS could be a promising candidate for the prevention and healing of bone-related diseases.

ENOX2 (or tNOX): a new and old molecule with cancer activity involved in tumor prevention and therapy.

Cancer includes a number of related diseases due to abnormal cell proliferation that spreads to nearby tissues. Many compounds (physical, chemical and biological) have been used to try to halt this abnormal proliferation, but the therapeutic results are poor, due also to the side effects. It has been reported that ecto-nicotinamide adenine dinucleotide oxidase di-sulfide-thiol exchanger 2 (ENOX2), also known as tumor-associated nicotinamide adenine dinucleotide oxidase (tNOX), was found to be located on the cancer cell surface, essential for cancer cell growth. Capsaicin and other anti-oxidants are capable of inhibiting tNOX, causing apoptosis of cells, exerting anti-tumor activity. It is interesting that some authors reported that ENOX2 is present in the serum of cancer patients several years before the clinical symptoms of the tumor. However, this result has to be confirmed. In this article we discuss ENOX2 and its inhibition as a hope of improving cancer therapy.