Rheological and osteogenic effect of Agaricus blazei Murill polysaccharides on composite hydrogels based on HPMC/graphene oxide – A preliminary study

Abstract

This study aimed to prepare and preliminarily characterize the potential bone restorative effect of composite hydrogels based on hydroxypropylmethylcellulose (HPMC), graphene oxide (GO), and polysaccharides from Agaricus blazei Murill mushroom (PAb). The chemical composition and morphology of the biomaterials were analyzed using FTIR, XRD, SEM, and EDS. Rheological tests were conducted on the hydrogels to assess their flow properties for in vivo application and product stability. Cytotoxicity assays were performed using the GO (1–100µgmL–1) against human neutrophils. Additionally, an in vivo tooth extraction test was carried out by applying HPMC hydrogels containing GO and PAb directly into the alveoli to enhance oral bone restoration. The rheological behavior of the hydrogels followed the Ostwald de Waele model (R² > 0.99), with flow index (n) values below 1.0, indicating a pseudoplastic behavior. Furthermore, the consistency index (k) values increased with the addition of GO and PAb, suggesting a more complex structure, and altered flow behavior at lower shear rates. In the MTT assay, GO exhibited low cytotoxicity towards human neutrophils, maintaining cell viability above 95.0% even at high concentrations. For the in vivo study, a bisphosphonate-induced osteonecrosis model was used to assess bone tissue healing through macroscopic and radiographic analyses. A significant improvement was observed in the reduction of bone tissue loss in rats treated with the hydrogels compared to the negative control (ZA group). These findings indicate that composite hydrogels containing HMPC/GO/PAb have the potential to be used as biomaterials for mitigating bone loss.