Secretome analysis of rat osteoblasts during icariin treatment induced osteogenesis.

Osteoporosis is a serious public health problem and icariin (ICA) is the active component of the Epimedium sagittatum, a traditional Chinese medicinal herb. The present study aimed to investigate the effects and underlying mechanisms of ICA as a potential therapy for osteoporosis. Calvaria osteoblasts were isolated from newborn rats and treated with ICA. Cell viability, apoptosis, alkaline phosphatase activity and calcium deposition were analyzed. Bioinformatics analyses were performed to identify differentially expressed proteins (DEPs) in response to ICA treatment. Western blot analysis was performed to validate the expression of DEPs. ICA administration promoted osteoblast viability, alkaline phosphatase activity, calcium deposition and inhibited osteoblast apoptosis. Secretome analysis of ICA­treated cells was performed using two­dimensional gel electrophoresis and matrix­assisted laser desorption/ionization time­of­flight mass spectrometry. A total of 56 DEPs were identified, including serpin family F member 1 (PEDF), protein disulfide isomerase family A, member 3 (PDIA3), nuclear protein, co­activator of histone transcription (NPAT), c­Myc and heat shock protein 70 (HSP70). These proteins were associated with signaling pathways, including Fas and p53. Bioinformatics and western blot analyses confirmed that the expression levels of the six DEPs were upregulated following ICA treatment. These genes may be directly or indirectly involved in ICA­mediated osteogenic differentiation and osteogenesis. It was demonstrated that ICA treatment promoted osteogenesis by modulating the expression of PEDF, PDIA3, NPAT and HSP70 through signaling pathways, including Fas and p53.

Identification of candidate synovial membrane biomarkers after Achyranthes aspera treatment for rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic autoimmune disease whose main symptom is a heightened inflammatory response in synovial tissues. To verify the anti-arthritic activities of Achyranthes aspera and its possible therapy-related factors on the pathogenesis of RA, the saponins in A. aspera root were isolated and identified to treat the collagen-induced arthritis (CIA) rats. Phytochemical analysis isolated and identified methyl caffeate, 25-S-inokosterone, 25-S-inokosterone ß-D-glucopyranosyl 3-(O-ß-D-glucopyranosyloxy)-oleanolate, and ß-D-glucopyranosyl 3-(O-ß-D-galactopyranosyl (1→2)(O-ß-D-glucopyranosyloxy)-oleanolate as main compounds in the root of A. aspera. Proteomics was performed to determine the differentially expressed proteins in either inflamed or drug-treated synovium of CIA rats. Treatment resulted in dramatically decreased paw swelling, proliferation of inflammatory cells, and bone degradation. Fibrinogen, procollagen, protein disulfide-isomerase A3, and apolipoprotein A-I were all increased in inflamed synovial tissues and were found to decrease when administered drug therapy. Furthermore, Alpha-1-antiproteinase and manganese superoxide dismutase were both increased in drug-treated synovial tissues. The inhibition of RA progression shows that A. aspera is a promising candidate for future treatment of human arthritis. Importantly, the total saponins found within A. aspera are the active component. Finally, autoantigens such as fibrinogen and collagen could act as inducers of RA due to their aggravation of inflammation. Given this, it is possible that the vimentin and PDIA3 could be the candidate biomarkers specific to Achyranthes saponin therapy for rheumatoid arthritis in synovial membrane.

Characterization of two protein disulfide isomerases from the endocytic pathway of bloodstream forms of Trypanosoma brucei.

Proteins from the endocytic pathway in bloodstream forms of Trypanosome brucei are modified by the addition of linear poly-N-acetyllactosamine side chains, which permits their isolation by tomato lectin affinity chromatography. Antibodies against this tomato lectin binding fraction were employed to screen a cDNA expression library from bloodstream forms of T. brucei. Two cDNAs were prominent among those selected. These cDNAs coded for two putative protein disulfide isomerases (PDIs) that respectively contained one and two double-cysteine redox-active sites and corresponded to a single domain PDI and a class 1 PDI. Assays of the purified recombinant proteins demonstrated that both proteins possess isomerase activity, but only the single domain PDI had a reducing activity. These PDIs possess a number of unusual features that distinguish them from previously characterized PDIs. The expression of both is developmentally regulated, they both co-localize with markers of the endocytic pathway, and both are modified by N-glycosylation. The larger PDI possesses N-glycans containing poly-N-acetyllactosamine, a modification that is indicative of processing in the Golgi and suggests the presence of a novel trafficking pathway for PDIs in trypanosomes. Although generally PDIs are considered essential, neither activity appeared to be essential for the growth of trypanosomes, at least in vitro.