International Journal of Advances in Medical Biotechnology - IJAMB

Enhanced bone implant with porous polypropylene matrix coated with chitosan and hydroxyapatite

2024-10-17T10:51:48-03:00

Porous polymer matrix based on functionalized polypropylene coated with chitosan and hydroxyapatite was prepared to evaluate its body response and establish its ability to induce osteointegration and/or osteoconduction. 12 Sprague-Dawley rats were divided into 6 groups corresponding to 0, 1, 2, 4, 8 and 16 weeks of healing; a 5x1 mm bone defect was created in the proximal diaphysis of both tibiae. In the right member the composite to evaluate was introduced and the left member was used as control. Animals were sacrificed by CO₂ chamber and a radiographic and histological study was done. The implanted composite showed no evidence of foreign body reaction from the first week and maintained close contact with newly formed bone tissue. During the first two weeks a periosteal reaction penetrating the implant pores was observed. Osteogenic buds observed as mesenchymal cells condensations highly vascularized and newly trabecular bone formations were found within the implant pores. New bone formation was observed until the eighth week after implantation when morpho-structural adaptation began.

We concluded this matrix coated with chitosan and hydroxyapatite exhibited osteointegrated properties because it’s structurally binding to bone and osteoconductive properties due to adhesion, proliferation, and differentiation of the osteoblastic cells within their pores.

Exosome-loaded alginate hydrogels as modulators of B16-F10 melanoma cell migration

2024-11-19T10:45:52-02:00

Exosomes have gained attention as promising therapeutic agents in cancer treatment due to their ability to influence target cell phenotypes and modulate immune responses. Their role in tumor biology, however, is influenced by several factors, including the source of mesenchymal stem cells (MSCs), culture conditions, and the tumor microenvironment. This study aimed to evaluate the effects of exosomes derived from bone marrow MSCs of Sprague-Dawley rats, incorporated into alginate hydrogels (AH), on the migration and viability of murine melanoma (B16-F10) cells. Scanning electron microscopy revealed that the hydrogels preserved their structural integrity after exosome incorporation. Both AH and exosome-loaded AH (AHE) exhibited no cytotoxic effects, as the viability and colony-forming capacity of B16-F10 cells remained comparable to untreated controls. Notably, AHE significantly suppressed tumor cell migration, a critical step in cancer metastasis, whereas AH alone had no effect. These findings indicate that exosomes retained their functionality within the hydrogel matrix, effectively modulating cell migration. This study underscores the therapeutic potential of exosome-loaded hydrogels in regulating cancer cell behavior. Nonetheless, further research is needed to elucidate the molecular mechanisms involved and optimize the clinical application of exosome-integrated hydrogels.