Rheumatoid Arthritis: Feng J

Sun J, Lin Z, Feng J, Li Y, Shen B. · Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 30072, PR China. · Eur J Pharmacol. · Pubmed #18793632 No free full text.

Abstract: Since B cell activating factor belonging to tumor necrosis factor (TNF) family (BAFF) has been identified as a critical factor for B cell maturation and survival, convincing evidence indicates that deregulation of BAFF is involved in pathogenesis of B cell related autoimmune diseases. Blockade of BAFF activity significantly improves the symptoms of autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis both in animal models and clinical trials. Therefore, BAFF-targeting therapy is a promising approach to treat B cell related autoimmune diseases.

Feng J, Zhao W. · Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China. · Magn Reson Chem. · Pubmed #19402023 No free full text.

Abstract: Four new oligosaccharides (1-4), one new pregnane glycoside (5), and one new cardiac glycoside (6) were isolated from the roots of Periploca forrestii Schltr. (Asclepiadaceae), a traditional Chinese medicine used for the treatment of rheumatoid arthritis and wounds. Their structures were characterized on the basis of extensive analysis of NMR (1H, 13C NMR, 1H-1H COSY, HSQC, HMBC, TOCSY and ROESY) spectra.

Feng J, Zhang R, Zhou Y, Chen Z, Tang W, Liu Q, Zuo JP, Zhao W. · Department of Natural Products Chemistry, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China. · Phytochemistry. · Pubmed #18835000 No free full text.

Abstract: Nine pregnane glycosides containing peroxy functions in their sugar moieties (1-5 and 11-14), five oligosaccharides (6-10), six pregnane glycosides (15-20), and five cardiac glycosides (21-25) were isolated from the root barks of Periploca sepium Bge. (Asclepiadaceae) and the roots of Periploca forrestii Schltr. (Asclepiadaceae), two traditional Chinese medicines used for the treatment of rheumatoid arthritis. Among them, 1-8 are hitherto unknown. Their structures were characterized on the basis of spectroscopic analyses. In pharmacological testing, compounds 1-5 and 11-14 were found to exhibit inhibitory activity against the proliferation of T lymphocyte in vitro with IC50 values ranging from 0.29microM to 1.97microM, while the other components showed no significant inhibitory activity.

Chang H, Qin W, Li Y, Zhang J, Lin Z, Lv M, Sun Y, Feng J, Shen B. · Institute of Basic Medical Sciences, Beijing, PR China. · Mol Immunol. · Pubmed #17485112 No free full text.

Abstract: Anti-TNF antibody has been an effective therapeutic strategy for the diseases related to aberrant production of TNF-alpha, such as rheumatoid arthritis (RA) and Crohn's disease. The limitations of large molecule inhibitors in the therapy of these diseases prompted the search for other potent novel TNF-alpha antagonists. Antagonistic peptides, derived directly or designed rationally from complementarity-determining regions (CDRs) of neutralizing antibodies against TNF-alpha, have been demonstrated for their ability of inhibiting TNF-alpha. However, their activity is very low. In this study, to increase the affinity and bioactivity, human antibody variable region was used as scaffold to display antagonistic peptides, which were designed on the interaction between TNF-alpha and its neutralizing monoclonal antibody (mAb Z12). Based on the previously designed domain antibody (framework V(H)5), framework V(kappa)1 was used as light chain scaffold. On the basis of computer-guided molecular design method, a novel human scFv fragment (named as TSA1) was designed. Theoretical analysis showed that TSA1 could bind to TNF-alpha with more hydrogen bonds and lower binding free energy than the designed domain antibody. The biological experiments demonstrated that TSA1 could directly bind with TNF-alpha, competitively inhibit the binding of mAb Z12 to TNF-alpha and block the binding of TNF-alpha to TNFR I and TNFR II. TSA1 could also inhibit TNF-induced cytotoxicity on L929 cells and TNF-mediated NF-kappaB activation on HEK-293T cells. The bioactivity of TSA1 was significantly increased over the domain antibody. This study indicated that the framework of antibody variable region could serve as an ideal scaffold for displaying the peptides and provides a novel strategy to design TNF-alpha inhibitors with the ability to block the deleterious biological effects of TNF-alpha.

Qin W, Feng J, Li Y, Lin Z, Shen B. · Research Institute of Nephrology, Jinling Hospital, Nanjing, PR China. · Mol Immunol. · Pubmed #17125837 No free full text.

Abstract: Neutralizing of TNF-alpha has been proved effective in treatment of some autoimmune diseases, e.g. rheumatoid arthritis and Crohn's disease. Low molecular weight synthetic peptides can mimic the binding sites of TNF-alpha receptors and block the activity of TNF-alpha. In order to stabilize the conformation, increase the affinity and bioactivity, in this study, heavy chain variable region of human antibody was used as a scaffold to simultaneously display three peptides, which were designed on the interaction between TNF-alpha and it's neutralizing monoclonal antibody. On the basis of the structural character and physical-chemical property of the families of seven kinds of heavy chain variable regions (VH) in human antibodies, the fifth type of VH was screened as scaffold to display the antagonist peptide. Based on the computer-guided molecular design method, a novel domain antibody against TNF-alpha (named as ATD5) was designed as TNF-alpha antagonist. The theoretical study showed that ATD5 was more stable than displayed antagonist peptide. The binding activity with TNF-alpha was higher than free peptides. After expression and purification in Escherichia coli, ATD5 could bind directly with TNF-alpha and inhibit the binding of TNF-alpha to its two receptors, TNFR1 and TNFR2. ATD5 could also reduce the TNF-alpha-mediated cytotoxicity and inhibit TNF-alpha-mediated caspase activation on L929 cells in a dose dependent manner. The activity of ATD5 was significantly stronger than three peptides displayed by ATD5. This study provides a novel strategy for the development of new TNF-alpha inhibitors. This study demonstrates that it is possible to screen potential antagonists of TNF-alpha using in vitro analysis systems in combination with the computer-aided modeling method.

Sun J, Feng J, Li Y, Shen B. · Department of Molecular and Cellular Pharmacology, College of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, PR China. · Biochem Biophys Res Commun. · Pubmed #16793005 No free full text.

Abstract: B lymphocyte stimulator (BLyS) is a member of tumor necrosis factor (TNF) family. Because of its roles in autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and Sjogren syndrome (SS), BLyS antagonists have been tested to treat SLE- and RA-like symptoms in mice and obtained optimistic results. So far, reported BLyS antagonists were mostly decoyed BLyS receptors or anti-BLyS antibodies. In this study, a novel BLyS antagonist peptide, PT, was designed based on the modeling 3-D complex structure of BCMA and BLyS. The interaction mode of PT with BLyS was analyzed theoretically. The results of competitive ELISA demonstrated that PT could inhibit the binding of BCMA-Fc and anti-BLyS antibody to BLyS in vitro. In addition, PT could partly block the proliferating activity of BLyS on mice splenocytes. The BLyS antagonizing activity of PT was significant (p<0.05). This study highlights the possibility of using BLyS antagonist peptide to neutralize BLyS activity. Further optimization of PT with computer-guided molecular design method to enhance its biopotency may be useful in developing new BLyS antagonists to treat BLyS-related autoimmune diseases.

Feng J, Yang Z, Li Y, Hu M, Yu M, Qin W, Sun J, Shen B. · Institute of Basic Medical Sciences, Taiping Road, Beijing 100850, China. · Biochimie. · Pubmed #16626851 No free full text.

Abstract: Human interleukin-6 is involved in the maintenance and progression of several diseases such as multiple myeloma (MM), rheumatoid arthritis, or osteoporosis. Our previous work demonstrated that an interleukin-6 antagonist peptide (named PT) possessed potential bioactivity to antagonize the function of hIL-6 and could efficiently induce the growth arrest and apoptosis of XG-7 and M1 cells in a dose-dependent manner. In this study, the theoretical interaction of the peptide PT with its receptor was analyzed further more with molecular docking and molecular dynamics methods. The theoretical studies showed that PT possessed very high affinity to interleukin-6R and offered a practical means of imposing long-term blockade of interleukin-6 activity in vivo. According to the theoretical results, the biological evaluation of PT was researched on two different cells models with more sensitive approaches: (1) The antagonist activity of PT was studied on the interleukin-6 dependent MM cells (XG-7) cultured with interleukin-6. In the other interleukin-6 dependent MM cells (SKO-007), they survived themselves by auto/paracrine without the exogenous interleukin-6, and also could be antagonized by PT. The therapeutic value of PT only limited on the interleukin-6 dependent category in MM. (2) Myeloid leukemia M1 cells were induced for growth arrest and apoptosis in response to interleukin-6. The results supported our previous findings and showed that PT could be evaluated by protecting the cells from interleukin-6 induced apoptosis. In conclusion, PT could induce interleukin-6-dependent XG-7 and SKO-007 cells to apoptosis while inhibit interleukin-6-stimulated apoptosis in M1 cells.

Qin W, Feng J, Li Y, Lin Z, Shen B. · Institute of Basic Medical Sciences, P.O. Box 130 (3), Taiping Road, Beijing 100850, PR China. · J Biotechnol. · Pubmed #16522339 No free full text.

Abstract: Tumor necrosis factor-alpha (TNF-alpha) antagonists have become therapeutic drugs for immunological diseases including rheumatoid arthritis, inflammatory bowel disease, Crohn's disease, etc. Low molecular weight synthetic peptides can mimic the binding sites of TNF-alpha receptors and block the activity of TNF-alpha. Based on the 3-D complex structure of TNF-alpha with its neutralizing monoclonal antibody (Mab) Z12, an antagonistic peptide (AP) was rationally de novo designed. The designed AP possessed similar structural character and potential bioactivity with Mab Z12. AP could competitively inhibit the binding of Mab Z12 to TNF-alpha, TNF-alpha-meditated caspase activation and TNF-alpha-induced cytotoxicity on murine L929 cells with a dose-dependent fashion. This study highlights the potential of computation-aided method for the design of novel peptides with the ability to block the deleterious biological effects of TNF-alpha.