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BACKGROUND: The clinical application of Mongolian Medicine Erdun -uril in the treatment of osteoarthritis is effective, but its therapeutic effect and related mechanism are still unclear. OBJECTIVE: To observe the repairing process of osteoarthritis in rats by Mongolian Medicine Erdun-uril and analyze its mechanism. METHODS: Thirty male Sprague-Dawley rats (8 weeks of age) were selected to establsih an osteoarthritis model using intraarticular injection of sodium iodoacetate solution into the unilateral knee joint. Two weeks after modeling, the model rats were randomly divided into three groups: control group (n=6) was given normal saline by gavage, and low and high dose groups (n=12 per group) were given Erdun-uril 1.4 and 2 g, respectively, 3 times per day. After 2 and 4 weeks of continuous administration, blood samples, articular cartilage and periarticular bone tissue were taken from rats to detect changes in cartilage metabolic markers (cartilage oligomeric matrix protein, proteoglycan), bone metabolic markers (bone alkaline phosphatase, keratan sulfate), inflammatory markers (interleukin 6, tumor necrosis factor α), lipid metabolic markers (total cholesterol, triacylglycerol). Histopathological changes were also observed. RESULTS AND CONCLUSION: qRT-PCR results showed that after 2 and 4 weeks of administration, the mRNA expression of cartilage oligomeric matrix protein, proteoglycan and bone alkaline phosphatase and keratan sulfate in knee cartilage of rats were significantly reduced in the low and high dose groups compared with the control group (P < 0.05, P < 0.01, P < 0.001), with the reduction being more significant in the high dose group. After 2 and 4 weeks of administration, compared with the control group, serum tumor necrosis factor α and interleukin 6 levels were decreased (P < 0.01, P < 0.001) and total cholesterol and triacylglycerol levels were increased (P < 0.05, P < 0.01, P < 0.001) in the low and high dose groups, with the improvement being more significant in the high dose group. Hematoxylin-eosin staining results showed that in the control group, there were large defective areas on the surface of the knee cartilage with unknown structure and severe inflammatory cell infiltration; in the low dose group, the surface of the knee cartilage was rough with disordered cell arrangement and the cartilage structure did not improve significantly after 2 weeks of administration, while the number of inflammatory cells in the knee cartilage was reduced and the cartilage structure was restored to some extent after 4 weeks of administration; in the high dose group, the structure of the knee cartilage become clear after 2 weeks of administration and even clearer after 4 weeks of administration, and the inflammation was significantly reduced after 2 weeks of administration. To conclude, Mongolian Medicine Erdun-uril with better anti-inflammatory properties can improve cartilage metabolism and obviously alleviate osteoarthritis in rats. [ABSTRACT FROM AUTHOR]

BACKGROUND: Exosomes can improve the inflammatory microenvironment of the degenerated intervertebral disc. However, direct injection of exosomes into the degenerated intervertebral disc at local concentrations and transient release cannot guarantee sustained effects, so the in vivo therapeutic effect of exosomes alone is limited. OBJECTIVE: To observe the effect of exosome-loaded glucan/gelatin composite hydrogel on repairing rat degenerative intervertebral disc. METHODS: Exosomes were extracted from bone marrow mesenchymal stem cells of rats. Exosome-loaded dextran/gelatin composite hydrogels were prepared by Schiff crosslinking reaction, and the microstructure and elastic modulus of the hydrogels were detected. Sixty Sprague-Dawley rats were randomly divided into five groups, with 12 rats in each group. Group A was the normal control. In groups B, C, D, and E, the intervertebral disc degeneration model was established by percutaneous puncture. PBS, exosomes, glucan/gelatin composite hydrogel and exosome-loaded glucan/gelatin composite hydrogel were injected into the intervertebral disc in turn. At postoperative 8 weeks, imaging, histopathology and western blot assay were performed. RESULTS AND CONCLUSION: The exosome-loaded glucan/gelatin composite hydrogels presented a three-dimensional porous structure with interconnected pores. The pore size was 50-200 μm, and the elastic modulus was (4.41±0.23) kPa, respectively. The exosomes could be released continuously and stably in vitro for more than 20 days. At 8 weeks after operation, X-ray films exhibited that the intervertebral disc height index percentages of rats in groups B-E were lower than those in group A (P < 0.05). The intervertebral disc height index percentages of rats in groups C, D and E were higher than those in group B (P < 0.05), of which group E was the most obvious. At 8 weeks after operation, MRI examination showed compared with group A, the tissue structure of nucleus pulposus in groups B-E was damaged to different degrees. Compared with group B, the tissue structure of nucleus pulposus in groups C-E was improved to varying degrees, among which group E had the most obvious improvement. Hematoxylin-eosin staining and saffron O staining at 8 weeks after surgery exhibited that the structure of the nucleus pulposus in group B was severely damaged and only contained a small amount of collagen. Compared with group B, the structure of nucleus pulposus in groups C-E was improved, and the structure of nucleus pulposus in group E was finer, clearer, regular and had the most collagen content. Western blot assay demonstrated that compared with group A, the expression levels of type II collagen and proteoglycan protein in groups B-E were decreased (P < 0.05). Compared with group B, the expression levels of type II collagen and proteoglycan protein in groups C-E were increased (P < 0.05), and those in group E were the most obvious. It is concluded that the dextran/gelatin composite hydrogel loaded with exosomes injected into the degenerative intervertebral disc can restore the intervertebral disc height and intervertebral disc signal intensity, restore the tissue structure, and delay intervertebral disc degeneration to a certain extent. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a common and heterogeneous post-translational modification (PTM), glycosylation takes part in a wide variety of biological processes. Precision analysis of glycosylation is of great value for the determination of their functional roles and the discovery of novel disease biomarkers. Mass spectrometry-based identification of intact glycopeptide has become increasingly popular in glycosylation studies due to its ability for high-throughput analysis of glyco-sites and glycan modifications simultaneously. Variable modification searching strategy by setting database glycans as variable modification on glycosites is commonly used in the identification of intact glycopeptides. Due to the issues of search space and random match, the performance of variable modification strategy is affected by the size of glycan database adopted in analysis. Inappropriate using of glycan databases in intact glycopeptide identification often results in poor analysis coverage or high false positive rate. In addition, the misassignment of precursor, which causes incorrect derivation of mass value of glycopeptides, is also frequently observed in the identification process and leads to incorrect glycopeptide spectrum interpretation. As only peptide fragment ions in glycopeptide spectra are matched by setting the glycan part as variable modifications, the confidence of precursor assignment and glycopeptide identification can not be fully assessed by spectrum matching scores, which are often solely based on peptide fragment ions. The spectrum features of glycopeptide precursor, including elution profiles and intensity distributions of isotopic peak list, can be utilized to screen the incorrect glycopeptide results caused by isotopic shift, which are great helpful to elevate the reliability of identification results. In this work, the effect of glycan databases on the performance of variable modification searching was firstly investigated by using the dataset of yeast as a benchmark, since only oligo-mannose N-glycans were synthesized in yeast. Applying the method of precursor feature screening, the false discovery rate of glycopeptide identification was reduced from 11.31% to 4.15% on the dataset of yeast. Further analysis for the glycan part of glycopeptide results proved that precursor feature screening was able to remove false positive identifications at high specificity. In addition, investigation on the dataset of mouse tissues also indicated that the precursor feature screening method could be utilized to improve the identification confidence for the analysis of complex samples. Being different from fragment ion matching, precursor feature screening method provides an alternative approach to assess the confidence of glycopeptide identification by utilizing the information of precursor isotopic peaks, which is of potential helpful for glycosylation studies. [ABSTRACT FROM AUTHOR]

BACKGROUND: The mechanism of intervertebral disc degeneration is complicated. The activation of inflammatory pathways, the proliferation of inflammatory factors, and the excessive accumulation of reactive oxygen species can all accelerate the process of intervertebral disc degeneration. Curcumin is a natural drug extracted from traditional Chinese medicine curcuma, which has pharmacological effects such as inhibiting inflammation, antioxidant stress and so on. OBJECTIVE: To study the curative effect of local injection of curcumin loaded sustained-release microspheres on intervertebral disc degeneration in rats. METHODS: (1) Sustained release microspheres loaded with curcumin nanoparticles were prepared by microfluidic technology. The drug release and degradation were evaluated in vitro. (2) Sustained-release microspheres and unloaded microspheres were co-cultured with nucleus pulposus cells in vitro. Cells cultured alone were used as controls. The three groups of cells were cultured in normal environment and oxidative stress environment (adding H2O2). The activity and proliferation of nucleus pulposus cells were evaluated by CCK-8 assay and live/dead staining. The expression levels of related factors were analyzed by qRT-PCR. (3) A total of 30 SD rats were randomly divided into normal group, degeneration group, unloaded microsphere group, curcumin group and sustained-release microsphere group (n=6 per group). The models of intervertebral disc degeneration were established by percutaneous puncture in the 7-8 and 8-9 segments of the caudal vertebra of the rats. The corresponding solutions were injected into the degenerated intervertebral discs in the unloaded microsphere group, the curcumin group, and the sustained-release microsphere group. After 4 weeks, the changes of intervertebral disc tissue structure were observed by imaging and histology. RESULTS AND CONCLUSION: (1) The sustained-release microspheres could slowly and continuously release curcumin, and the total amount of curcumin released was (84.11±2.71)% at 28 days. In PBS containing collagenase, the mass of the sustained-release microspheres gradually decreased and disappeared at the 5th week. (2) The results of CCK-8 assay and live/dead staining indicated that the sustained-release microspheres did not reduce the proliferation ability of nucleus pulposus cells under normal conditions and could maintain the proliferation activity of nucleus pulposus cells under oxidative stress compared with unloaded microspheres. qRT-PCR experiments indicated that compared with the normal environment, the oxidative stress environment activated the overexpression of mRNA of various inflammatory factors in nucleus pulposus cells. Under oxidative stress, the mRNA expression levels of tumor necrosis factor-α, interleukin-1β, interleukin-6 and matrix metalloproteinase 3 in the sustained-release microsphere group were decreased and mRNA expression of type II collagen and proteoglycan was increased compared with the unloaded microsphere group and the control group. (3) The results of animal in vivo experiments showed that the imaging and histological evaluation of the unloaded microsphere group was not significantly different from that of the degeneration group after 4 weeks. The intervertebral space height and MRI score of the curcumin group were improved to a certain extent compared with the degeneration group and the unloaded microsphere group at 1 week, but the imaging and histological evaluations at 4 weeks were not as good as those of the sustained-release microsphere group. (4) In conclusion, curcumin sustained-release microspheres could inhibit the apoptosis of nucleus pulposus cells induced by H2O2 and retard the progression of intervertebral disc degeneration. Its mechanism is associated with inhibiting the nuclear factor κB pathway and reducing the level of oxidative stress. [ABSTRACT FROM AUTHOR]

A variety of strategies to improve the nitrogen and phosphorus removal performance o£ granular sludge under low carbon source conditions were summarized, including time aeration strategy, space aeration strategy, water inflow strategy, configuration optimization strategy and microbial regulation strategy・ The specific research schemes of environmental contradictions, inhibition of glycans and coexistence of multiple nitrogen and phosphorus removal methods in the process of aerobic granular sludge nitrogen and phosphorus removal were described・ The traditional cogn让ion should be broken and how to improve the stability of AGS and the activity of functional bacteria should be considered from the perspective of system instability・ The application prospect of introducing some" gradient strategies of SBR into continuous flow to improve nitrogen and phosphorus removal performance and stability is proposed・ It provides scientific reference for the engineering application of mainstream aerobic granular sludge process. [ABSTRACT FROM AUTHOR]

Combined with mass spectrometry, ion spectroscopy can obtain a spectrum of the target ion by measuring its intensity change, which is induced by laser strength and wavelength. It integrates the high sensitivity of mass spectrometry and the structural specificity of spectroscopy, and thus proves to be very useful in structure characterization of complex biomolecules, such as proteins, peptides, glycans, oligonucleotides, etc. However, the electronic or vibrational spectra becomes too complex to be resolved when analyzing isomeric ions. Ion mobility spectrometry (IMS) allows ionized molecules to be separated on the basis of mobilities in the gas phase, and its coupling with electrospray and MALDI ion sources opens up possibilities for structural studies of a wide range of biomolecules in gas-phase. Ion mobility spectrometry coupled with mass spectrometry has seen spectacular growth for the last two decades. The introduction of ion mobility to ion spectroscopy has been of growing attention in recent years. While IMS can be used as an isomer filter to reduce spectral congestion of ions, highly resolved ion spectra facilitates the identification of the isomer peaks separated by IMS. Taken together, spectra and collision cross section (CCS) measurements on the same system prove to be rather useful for structural analysis and provide clearer spectroscopic fingerprint to isomers. Therefore, this paper briefly summarized advances in ion spectroscopy research based on ion mobility-mass spectrometry technology, introduced representative researches, and prospected possible development in multi-dimensional structural mass spectrometry. [ABSTRACT FROM AUTHOR]

Glycosylation is one of the most important post-translational modifications (PTM), mediating physiological processes like cell adhesion, cell proliferation, cell signaling, and immune responses. The special functionality of glycosylation for cancer progression and metastasis were reported in recent researches. Analytical methods based on mass spectrometry (MS), especially liquid chromatography mass spectrometry (LC-MS), are the routine practices for protein glycosylation research. However, due to the high complexity and multiformity of glycan structures, as well as the existence of numerous isomers, in-depth analysis of glycosylation ends up as a major challenge for conventional LC-MS-based method. Ion mobility separation is a promising approach to fill the gap as it provides an additional separation dimension for mass spectrometry analysis based on structures and charges of the gas-phase ions. As a technology with an entirely different separation mechanism from that of liquid chromatography, ion mobility spectrometry (IM) has several properties superior to other separation facilities. First of all, unlike liquid chromatography or capillary electrophoresis which demand minutes of separation time, IM only requires a few milliseconds to finish the separation, and it is well compatible with fast mass spectrometry analysis. Besides, as a separation technique for gas phase ions, IM can be modularized and readily integrated into full-fledged LC-MS system. Most importantly, IM is proved to have great potential in glycan isomer discriminations. Given the aforementioned merits, ion mobility mass spectrometry (IM-MS) is gaining attention from glycomics community. This review summarized the basic principles of IM-MS and its applications in protein glycosylation research for the past five years. The means of enhancing isomeric separation performance of glycans were comprehensively discussed, including derivatization, forming metal and other noncovalent adducts, and utilizing high-resolution ion mobility spectrometry implementation. The various approaches of leveraging collision cross section (CCS) values to assist glycan identification and isomer discrimination were also summarized. Furthermore, as two monosaccharides with great biological and pathological significance, the IM-MS applications on fucoses and sialic acids were given special attention. As for glycopeptides, innovative spectra matching algorithms, novel ion activation techniques to facilitate glycan and peptide elucidations, and brand new quantification strategies for isomers were included, along with various glycoproteomic applications of IM-MS on biological samples. Finally, in terms of IM-MS applications in glycoprotein research, investigations of conformational properties, 3 D structures, stabilities, and protein-protein interactions were covered. It was concluded that IM-MS is a promising method for protein glycosylation research with great potential. [ABSTRACT FROM AUTHOR]

Recently, different types of ion mobility techniques have sprung up. Combined with mass spectrometry, the utility of ion mobility spectrometry has been enhanced in metabolomics, natural products, characterization of supramolecular materials, and other research fields. Since small molecule metabolites provide deep insight into the dynamic phenotypes of biological systems and show potential value in disease diagnosis and functional interpretation, in-depth analysis of small molecule metabolites plays a key role in medicine and pharmacy. The potential benefits of ion mobility spectrometry used in chiral recognition of amino acids, structural analysis of glycans, and structural characterization of lipids and steroids have become the specific focus of work. However, small molecule metabolites possess a wide variety of chemical properties, ubiquitous isomerism, and various biological functions, so it is difficult to analyze small molecule metabolites comprehensively. On the other hand, small molecule metabolites with low concentrations usually exist in various complex biological matrices, such as plasma, feces, urine, saliva, sweat, infected tissues or exudates, breath, and breast milk, which pose additional challenges to researchers. Over the last few decades, ion mobility-mass spectrometry (IM-MS) has undergone inordinate growth in instrument development and performance, which has opened a new door to rapidly analyze small molecular metabolites in complex biological matrices. Small molecular metabolites and their isomers can be distinguished and characterized in milliseconds by IM-MS that offer high selectivity and three-dimensional information about them, including mass-charge ratio, collision cross section (CCS), and structural information. The collision cross section can be used as an additional identification basis in targeted and untargeted analyses. In this paper, the main commercial IM-MS instruments were briefly covered. An overview of the latest applications in small molecular metabolites was offered. Additionally, the advantages and shortcomings of IM-MS in the analysis of small molecular metabolites were discussed. And the future application of particular and unknown metabolites by IM-MS in the studies on the biological mechanism and precision medicine was prospected. [ABSTRACT FROM AUTHOR]

IgG is a key glycoprotein involved in humoral immunity, which plays important roles in removing toxins, activating the corresponding receptors and complement, and regulating the immune response by recognizing specific antigens. The glycosylation of IgG mainly belongs to N-glycosylation, and IgG carries a conserved N-glycosylation site at the site of Asn297 in the constant region, which not only affects the physicochemical properties, such as structure, solubility and stability of IgG, but also impacts its biological function. Therefore, the identification of IgG glycosylation contributes to the deep understanding of immune molecular mechanism, as well as the significance in early diagnosis of disease, prognostic evaluation, and development of therapeutic antibody drugs. In this review, mass spectrometry-based identification methods of IgG glycosylation and their applications were reviewed in the levels of glycan, glycopeptide and intact protein of IgG. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan Agricultural Sciences is the property of Editorial Board of Journal of Henan Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)