Biology subjects

Long, Z.

Publications and source records attributed to Long, Z..

3 recordsLinked to original sources

bioRxiv2021

Age-related Cellular and Microstructural Changes in the Rotator Cuff Enthesis

Rotator cuff injuries increase with age. The enthesis is the most frequent site of rotator cuff injury and degeneration. Understanding age-related changes of the enthesis are essential to determine the mechanism of rotator cuff injuries, degeneration, and to guide mechanistically driven therapies. In this study, we explored age-related cellular changes of the rotator cuff enthesis in young, mature, and aged rats. Here we found that the aged enthesis is typified by an increased mineralized zone and decreased non-mineralized zone. Proliferation, migration, and colony forming potential of rotator cuff derived cells (RCECs) was attenuated with aging. The tenogenic and chondrogenic potential were significantly reduced, while the osteogenic potential increased in aged RCECs. The adipogenic potential increased in RCECs with age. This study explores the cellular differences found between young, mature, and aged rotator cuff enthesis cells and provides a basis for further delineation of mechanisms and potential therapeutics for rotator cuff injuries.

cell biology↗

bioRxiv2020

Computational Analysis of the Metal Selectivity of Metal Metalloproteinase 8

Matrix metalloproteinase (MMP) is a class of metalloenzyme that cleaves peptide bonds in extracellular matrices. Their functions are important in both health and disease of animals. Here using quantum mechanics simulations of the MMP8 protein, the coordination chemistry of different metal cofactors is examined. Comparisons found that Jhan-Teller effects in Cu(II) destabilize the wild-type MMP8 but a histidine to glutamine mutation at residue number 197 can potentially allow the MMP8 protein to utilize Cu(II) in reactions. Simulations also demonstrates the requirement of a conformational change in the ligand before enzymatic cleavage. The insights provided in here will assist future protein engineering efforts utilizing the MMP8 protein.Competing Interest StatementThe authors have declared no competing interest.View Full Text

biophysics↗

bioRxiv2020

Metabolomic markers of colorectal tumor with different clinicopathological features

BackgroundColorectal cancer (CRC) is the result of complex interactions between the tumors molecular profile and metabolites produced by its microenvironment. Despite recent studies identifying CRC molecular subtypes, a metabolic classification system is still lacking. We aimed to explore the distinct phenotypes and subtypes of CRC at the metabolic level. MethodsWe conducted an untargeted metabolomics analysis of 51 paired tumor tissues and adjacent mucosa using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry. Multivariate analysis including principal component analysis, orthogonal partial least squares discriminant analysis and heat maps, univariate analysis, and pathway analysis were used to identify potential metabolic phenotypes of CRC. Unsupervised consensus clustering were used to identify robust metabolic subtypes, and evaluated their clinical relevance. ResultsA total of 173 metabolites (including nucleotides, carbohydrates, free fatty acids, and choline) were identified between CRC tumor tissue and adjacent mucosa. We found that lipid metabolism was closely related to the occurrence and progression of CRC and CRC tissues could be divided into three subtypes, and statistically significant correlations between different subtypes and clinical prognosis were observed. ConclusionsCRC tumor tissue exhibits distinct metabolic phenotypes. Metabolic differences between subtypes may provide a basis and direction for further clinical individualized treatment planning.

cancer biology↗