Glucosamine Hydrochloride and N-Acetylglucosamine Influence the Response of Bovine Chondrocytes to TGF-β3 and IGF in Monolayer and Three-Dimensional Tissue Culture

Abstract

BACKGROUND: Glucosamine hydrochloride (GlcNÁHCl) has been shown to inhibit cell growth and matrix synthesis, but not with N-acetyl-glucosamine (GlcNAc) supplementation. This effect might be related to an inhibition of critical growth factors (GF), or to a different metabolization of the two glucosamine derivatives. The aim of the present study was to evaluate the synergy between GlcNÁHCl, GlcNAc, and GF on proliferation and cartilage matrix synthesis. METHOD: Bovine chondrocytes were cultivated in monolayers for 48 h and in three-dimensional (3D) chitosan scaffolds for 30 days in perfusion bioreactors. Serum-free (SF) medium was supplemented with either growth factors (GF) TGF-b (5 ng mL -1 ) and IGF-I (10 ng mL -1 ), GlcNÁHCl or GlcNAc at 1mM each or both. Six groups were compared according to medium supplementation: (a) SF control; (b) SF ? GlcNÁHCl; (c) SF ? GlcNAc; (d) SF ? GF; (e) SF ? GF ? GlcNÁHCl; and (f) SF ? GF ? GlcNAc. Cell proliferation, proteoglycan, collagen I (COL1), and collagen II (COL2) synthesis were evaluated. RESULTS:The two glucosamines showed opposite effects in monolayer culture: GlcNÁHCl significantly reduced proliferation and GlcNAc significantly augmented cellular metabolism. In the 30 days 3D culture, the GlcNÁHCl added to GF stimulated cell proliferation more than when compared to GF only, but the proteoglycan synthesis was smaller than GF. However, GlcNAc added to GF improved the cell proliferation and proteoglycan synthesis more than when compared to GF and GF/GlcNÁHCl. The synthesis of COL1 and COL2 was observed in all groups containing GF. CONCLUSION: GlcNÁHCl and GlcNAc increased cell growth and stimulated COL2 synthesis in long-time 3D culture. However, only GlcNAc added to GF improved proteoglycan synthesis.

Immunomodulatory Effects of N-Acetyl Chitooligosaccharides on RAW264.7 Macrophages

“…The GlcNAcylation of transcription factors can regulate cellular processes and the addition of GlcN, GlcNAc, COS, and NACOS can improve these effects. The protein GlcNAcylation levels of different cells affect their cell responses through different pathways, including T/B cell activation [46,47], macrophage activation [48], chondrocyte inflammatory responses [49,50], and vascular endothelial inflammatory responses [18], among others.…”

Targeting cell surface glycans with lectin-coated fluorescent nanodiamonds

“… 77 This effect could ultimately be beneficial in utilizing WGA–FND as a nanocarrier for anti-cancer drug delivery. The presence of glycan moieties attached to serum proteins found in cell culture media (albumin, transferrin, aprotinin, fetuin, and fibronectin), 78 which are targets of AAL and WGA lectins, could also reduce cell viability 79 as the lectins may interact with the glycoproteins in the media and remove them from nutritional access to the cells. AAL conjugated microparticles have been utilized without cytotoxic effects in gut cells of the small intestine previously although these particles induced cytokine (IL-2, IFN-y, IL-10, IL-5) secretion with increasing concentrations (50–400 μg) 80 which may have produced a similar inflammation in the brain cells investigated here at the higher (15–30 μg mL −1 ) concentrations that affected cell viability.…”

Determination and Correlation of Solubility of N-Acetylglucosamine in Four Aqueous Binary Solvents from 283.15 to 323.15 K

“…A few NAG reports have already been made public. , But the current studies on NAG’s solubility are not as prevalent as research on its applications in different fields. Hesketh et al found that oral NAG can alter the insulin content, which proves that it may play a certain role in the treatment of diabetes .…”