Hyaluronic Acid Gel-Based Scaffolds as Potential Carrier for Growth Factors: An In Vitro Bioassay on Its Osteogenic Potential

Abstract

Hyaluronic acid (HA) has been utilized for a variety of regenerative medical procedures due to its widespread presence in connective tissue and perceived biocompatibility. The aim of the present study was to investigate HA in combination with recombinant human bone morphogenetic protein 9 (rhBMP9), one of the most osteogenic growth factors of the BMP family. HA was first combined with rhBMP9 and assessed for the adsorption and release of rhBMP9 over 10 days by ELISA. Thereafter, ST2 pre-osteoblasts were investigated by comparing (1) control tissue culture plastic, (2) HA alone, and (3) HA with rhBMP9 (100 ng/mL). Cellular proliferation was investigated by a MTS assay at one, three and five days and osteoblast differentiation was investigated by alkaline phosphatase (ALP) activity at seven days, alizarin red staining at 14 days and real-time PCR for osteoblast differentiation markers. The results demonstrated that rhBMP9 adsorbed within HA scaffolds and was released over a 10-day period in a controlled manner. While HA and rhBMP9 had little effect on cell proliferation, a marked and pronounced effect was observed for cell differentiation. rhBMP9 significantly induced ALP activity, mRNA levels of collagen1α2, and ALP and osteocalcin (OCN) at three or 14 days. HA also demonstrated some ability to induce osteoblast differentiation by increasing mRNA levels of OCN and increasing alizarin red staining at 14 days. In conclusion, the results from the present study demonstrate that (1) HA may serve as a potential carrier for various growth factors, and (2) rhBMP9 is a potent and promising inducer of osteoblast differentiation. Future animal studies are now necessary to investigate this combination approach in vivo.

A role for orphan nuclear receptor liver receptor homolog-1 (LRH-1, NR5A2) in primordial follicle activation

“…Several were regulators of ion transport or ion balance, including Atp8a2 , Gabre , and Slc30a3 , while several others were regulators of lipid binding or metabolism, including Pla2g4c , Osbp2 , and Atp8a2 . Wnt signaling is a positive regulator of both granulosa cell proliferation 55 and epithelial-to-mesenchymal transition (reviewed in 56 ). The suppressor of Wnt signaling, Tle2 57 was more abundant in primordial follicles and in cKO ovaries.…”

Collagen Fiber Array of Peritumoral Stroma Influences Epithelial-to-Mesenchymal Transition and Invasive Potential of Mammary Cancer Cells

“…Extracellular vesicles, including both the smaller exosomes (30–100 nm) and the larger microvesicles (100–1000 nm) represent one of the structural and functional components of normal ECM; they affect matrix organization, regulation of cells within it, and physical properties of soft connective tissues, bone, cartilage and dentin [9,10,11]. In cancer, they contain second messengers, matrix metalloproteinases (MMPs), syndecans, HA, allow communications between cancer cells and stroma cells, and play a role in favoring cancer cell invasion and metastasis [12,13,14,15].…”

Effect of hyaluronic acid on osteoblast function in vivo and on fracture healing in an experimental rabbit model

“…Sá found that low concentrations of HA (1, 10, and 100 ng/mL) had no effect on osteoblast activity but reported that methylthiazolyl tetrazolium bromide (MTT) and immunofluorescence assays found that a high concentration (1 g/L) for 48 h decreased osteoblast viability [9] . Von Kossa calcium staining of osteoblast cultures showed that 100 ng/mL HA significantly increased the area of nodule formation and RT-PCR confirmed that that HA was associated with type I and III collagen, osteocalcin, and bone morphogenetic protein 2 and 4 expression [11] . Injection of 1% HA into the alveolar fossa after tooth extraction was found to increase the deposition of mineralized bone and osteoblast number [8] .…”