Moleküler Biyoloji ve Genetik

Bu koleksiyon için kalıcı URI

http://hdl.handle.net/11527/25959

Gözat

Son Başvurular

Şimdi gösteriliyor 1 - 2 / 2
  • Öge
    Locally released dexamethasone and its effects on osteogenic activity at implant-tissue interface
    (Wiley, 2024) Kerem, Gizem ; Önder, Sakip ; Kılıç, Abdulhalim ; orcid.org/0000-0001-8170-7929 ; orcid.org/0000-0002-8629-3830 ; Moleküler Biyoloji ve Genetik
    The osseointegration of titanium implants within the host tissue holds crucial importance. The introduction of functional coatings at tissue—implant interface enhances the bioactivity of titanium implants, improves their therapeutic outcomes, and enhances the effectiveness of treatments. In this study, we focused on enhancing the bioactivity of titanium-based implant materials by coating the titanium surfaces with chitosan microspheres, which are loaded with osseointegration-promoting agent dexamethasone (DEX). Initially, chitosan microspheres were successfully produced, followed by DEX loading through diffusion, resulting in a drug loading efficiency of around 50.2 (wt %). The subsequent drug release profile displayed a 24-hour duration, releasing approximately 32.6 (wt %) of the loaded DEX. In cell proliferation assays using human osteosarcoma (SAOS-2) cells, Ti surfaces coated with DEX-loaded chitosan microspheres initially exhibited lower cell numbers compared with DEX-free ones. This observation was attributed to transient osteogenic differentiation effects of DEX, since a notable increase in cell proliferation was observed on the 7th day. Von Kossa staining revealed mineralization beginning on the 14th day, particularly evident in DEX-loaded samples. Moreover, alkaline phosphatase (ALP) activity displayed a pattern of initial increase and subsequent decrease, with DEX release from chitosan microspheres showing a clear influence on the osteogenic differentiation, especially on the 7th day. These findings align with literature, highlighting DEX's potential to enhance osteogenic differentiation and cellular behavior on chitosan microsphere-coated titanium surfaces. This study emphasizes the promising implications for functionalizing surfaces of implant materials with DEX-loaded chitosan microspheres to improve their biocompatibility and bioactivity.
  • Öge
    PIN1 is a novel interaction partner and a negative upstream regulator of the transcription factor NFIB
    (Wiley, 2024) Kumbasar, Aslı ; Sarıtaş Erdoğan, Sinem ; Yılmaz, Ahmet Erdal ; orcid.org/0000-0002-9529-0877 ; orcid.org/0009-0004-6202-2755 ; orcid.org/0000-0001-8574-2756 ; Moleküler Biyoloji ve Genetik
    NFIB is a transcription factor of the Nuclear Factor One (NFI) family that is essential for embryonic development. Post-translational control of NFIB or its upstream regulators have not been well characterized. Here, we show that PIN1 binds NFIB in a phosphorylation-dependent manner, via its WW domain. PIN1 interacts with the well-conserved N-terminal domains of all NFIs. Moreover, PIN1 attenuates the transcriptional activity of NFIB; this attenuation requires substrate binding by PIN1 but not its isomerase activity. Paradoxically, we found stabilization of NFIB by PIN1. We propose that PIN1 represses NFIB function not by regulating its abundance but by inducing a conformational change. These results identify NFIB as a novel PIN1 target and posit a role for PIN1 in post-translational regulation of NFIB and other NFIs.