In-depth characterization of 1,4-butanediol diglycidyl ether substituted hyaluronic acid hydrogels.

BDDE substituted HA hydrogels remain the most commonly used HA product in the biomedical field. The physical and biochemical properties of the hydrogels are dependent on the degree of modification and substitution patterns/positions, thus, characterizing their fine structure is of great importance for quality assurance. In this study, we developed novel LC-MS methods for accurate determination of MoD as well as in-depth characterization of the linkage network. Fragments resulted from enzymatic depolymerization were resolved by a porous graphitic carbon column followed by online tandem-MS for determining the modification site/residue. With high-resolution separation, two types of previously unknown structures were detected in the cross-linked fragments of 2-B-2 and 4-B-2. Based on the feature of resistance to NaBH4 reduction, these structures contain a GlcNAc residue modified at OH1. This special sugar unit likely derived from reducing end of the native polysaccharide could be a signature to discriminate subtle batch to batch variations.

Heparanase Expression Propagates Liver Damage in CCL4-Induced Mouse Model.

Heparanase is elevated in various pathological conditions, primarily cancer and inflammation. To investigate the significance and involvement of heparanase in liver fibrosis, we compared the susceptibility of wild-type (WT) and heparanase-overexpressing transgenic (Hpa-tg) mice to carbon tetrachloride (CCL4)-induced fibrosis. In comparison with WT mice, Hpa-tg mice displayed a severe degree of tissue damage and fibrosis, including higher necrotic tendency and intensified expression of smooth muscle actin. While damage to the WT liver started to recover after the acute phase, damage to the Hpa-tg liver was persistent. Recovery was attributed, in part, to heparanase-stimulated autophagic activity in response to CCL4, leading to increased apoptosis and necrosis. The total number of stellate cells was significantly higher in the Hpa-tg than the WT liver, likely contributing to the increased amounts of lipid droplets and smooth muscle actin. Our results support the notion that heparanase enhances inflammatory responses, and hence may serve as a target for the treatment of liver damage and fibrosis.

Genetic polymorphisms in COL18A1 influence the development of osteosarcoma.

We conducted a case-control study to investigate the association of COL18A1 D104N polymorphism in the development of osteosarcoma in a Chinese population. Between May 2012 and May 2014, 141 patients with pathologically proven osteosarcoma and 341 were selected into this study. Genotyping of COL18A1 D104N was analyzed using polymerase chain reaction (PCR) coupled with restriction fragment length polymorphism (RFLP). By logistic regression analysis, we found that individuals with the NN genotype of COL18A1 D104N were significantly associated with an increased risk of osteosarcoma when compared with the DD genotype (OR=20.97, 95% CI=2.74-933.42). In dominant model, the NN+DN genotype of COL18A1 D104N had a 1.99 fold risk of osteosarcoma when compared with the DD genotype. Moreover, the NN genotype was correlated with a 20.45 fold risk of osteosarcoma when compared with the DN+DD genotype in recessive model. However, we did not find significant interaction between COL18A1 D104N polymorphism and Enneking stage, histological subtype, tumor metastasis and tumor location of patients with osteosarcoma. In conclusion, our study suggests that the homozygous DN and NN genotypes of COL18A1 D104N were associated with the risk of osteosarcoma.