Protective effects of benzisothiazolylamidines on IL-1 beta induced alterations in human articular chondrocyte metabolism

4-Thiazolidinone Derivatives as MMP Inhibitors in Tissue Damage: Synthesis, Biological Evaluation and Docking Studies

Nine 2-(1,2-benzothiazol-3-yl)-N-(4-oxo-2-phenyl-1,3-thiazolidin-3-yl)propanamides combining a benzisothiazole and 4-thiazolidinone in one framework were designed and synthesized. The aim of the study was to verify their effectiveness to affect the inflammatory/oxidative process in which free oxygen and nitrite (ROS and RNS) radicals, inflammatory mediators, such as nuclear factor κB (NF-κB), and matrix metalloproteinases (MMPs) are involved. Docking studies of all the compounds were performed in order to explore their binding mode at the MMP-9 protein. An appreciable anti-inflammatory/potential wound healing effects of the tested compounds was highlighted. Derivative 23, bearing a 4-carboxyphenyl substituent at C2 of the 4-thiazolidinone ring, exhibited the highest activity, being able to inhibit MMP-9 at nanomolar level(IC50 = 40 nM).

Evaluation of the anti-inflammatory/chondroprotective activity of aldose reductase inhibitors in human chondrocyte cultures

2-Thioxo-4-thiazolidinone derivatives active as aldose reductase inhibitors were able to control key inflammatory/degenerative events induced by IL-1β in human chondrocytes, appearing to be promising candidates in the search for novel anti-inflammatory agents.

Chondroprotective and anti-inflammatory effects of S-methylisothiourea, an inducible nitric oxide synthase inhibitor in cartilage and synovial explants model of osteoarthritis

Objectives

To study the chondroprotective and anti-inflammatory potential of inducible nitric oxide synthase (iNOS) inhibitor S-methylisothiourea (SMT) in in-vitro model.

Methods

Rabbit cartilage explants were stimulated with recombinant human interleukin 1β (rhIL-1β), and the chondroprotective and anti-inflammatory effects of SMT were investigated. Rat synovial explants were stimulated with LPS, and the anti-inflammatory effect of SMT on synovium was studied. To examine the role of SMT in synovial inflammation mediated cartilage damage, LPS stimulated synovial explants were cultured with dead cartilage with or without SMT for 72 h. The culture medium was analysed for sulfated glycosaminoglycans (GAGs) and hydroxyproline as measure of proteoglycans and collagen degradation, respectively.

Key findings

SMT significantly reduced GAGs, hydroxyproline, matrix metalloproteinase (MMP)-13, tumour necrosis factor alpha (TNF-α), prostaglindin E2 (PGE2) and nitrite release in stimulated rabbit cartilage media indicating chondroprotective and anti-inflammatory effects of SMT in osteoarthritis (OA). Stimulated synovial explants caused release of nitrite, PGE2, IL-1β and TNF-α in the medium which were significantly reduced by SMT indicating its anti-inflammatory action. SMT significantly reduced GAGs and hydroxyproline in medium and shown protective effect against synovium-mediated cartilage damage.

Conclusions

SMT inhibited cartilage degradation, synovial inflammation and synovium-mediated cartilage damage, suggesting that SMT may be an agent for pharmacological intervention in OA.

Beneficial effect of interleukin-1 receptor antagonist protein on spinal cord injury recovery in the rat

We assessed the effect of treatment with the interleukin-1 receptor antagonist protein (IRAP) on morphological and functional recovery in a rat model of SCI. All sections were processed for immunohistochemistry, hematoxylin-eosin, and Nissl staining. Rats were assessed for hind limb motor function using the Basso, Beattie, and Bresnahan (BBB) hind limb locomotor rating scale and the inclined plane test. At 1, 48, and 72 h after operation, there was a significant increase in neurofilament proteins and brain-derived neurotrophic factor expression in the IRAP group I when compared with the saline group I and the sham-operated group I (P < 0.05). The mean inclined plane scores and BBB scores for the IRAP group II were higher than the saline group II at 1, 2, 3, and 4 weeks post-injury (P < 0.05). In conclusion, treatment with IRAP enhanced neuronal survival after SCI.

Effect of Phellodendron amurense in protecting human osteoarthritic cartilage and chondrocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicine has been widely using Phellodendron amurense Rupr. (Rutaceae) to treat various inflammatory diseases including arthritis.

AIM OF THE STUDY

This study investigated the effects of Phellodendron amurense in protecting cartilage, including regulating the levels of aggrecanases, matrix metalloproteinases (MMPs)/tissue inhibitor of metalloproteinase (TIMP), proinflammatory cytokines and signaling of the mitogen activated protein kinase (MAPK) pathway in human osteoarticular cartilage and chondrocytes.

MATERIALS AND METHODS

Explants from human osteoarthritis cartilage were cultured alone or in IL-1α for 7 days with or without Phellodendron amurense ethanol extract or celecoxib (40, 100, 200μg/ml). The effect of Phellodendron amurense on matrix degradation induced by IL-1α in human articular cartilage was assessed by staining, and the quantities of sulfated glycosaminoglycan (GAG) and type II collagen were calculated from the culture media. The levels of aggrecanases, MMPs, TIMP, and PGE(2) in the culture media were investigated using an enzyme-linked immunosorbent assay (ELISA). In addition, reverse transcription polymerase chain reaction (RT-PCR) evaluated the mRNA expression of aggrecanases, MMPs and TIMP. Furthermore, Western blot analysis was performed to identify the roles that Phellodendron amurense played in the ERK, JNK and p38 signaling pathways.

RESULTS

Phellodendron amurense showed no evident cytotoxicity on human articular cartilage. Phellodendron amurense significantly inhibited the IL-1α-induced degradation of GAG and type II collagen from human osteoarticular cartilage in a concentration-dependent manner. Celecoxib did not significantly inhibit IL-1α-induced release of GAG and only slightly reduced type II collagen. Phellodendron amurense also dose-dependently decreased the levels of aggrecanase-1 and -2, MMP-1, -3, and -13, whereas it increased TIMP-1 expression in human osteoarticular cartilage. Celecoxib only decreased MMP-1 and MMP-13 levels in human osteoarticular cartilage. In addition, Phellodendron amurense reduced the phosphorylation of extracellular signal regulated kinase (ERK)1/2, Jun NH2-terminal kinase (JNK) and activated phospho-p38 MAPK in a dose-dependent manner in human osteoarthritic chondrocytes.

CONCLUSIONS

Phellodendron amurense inhibited osteoarticular cartilage and chondrocyte destruction by inhibiting proteoglycan release and type II collagen degradation, down-regulating aggrecanases, MMP activities and phospho-ERK1/2, JNK and p38 MAP kinase signaling, and up-regulating TIMP-1 activity. Therefore, our results suggest that Phellodendron amurense is a potential therapeutic agent to protect cartilage against OA progression.

Therapeutic effect of Aralia cordata extracts on cartilage protection in collagenase-induced inflammatory arthritis rabbit model

AIM OF THIS STUDY

Aralia cordata has been used to alleviate symptoms of osteoarthritis (OA) in traditional medicine. However, there is no in vivo study related with the therapeutic effects and mechanisms of Aralia cordata. On the basis of this background, our study was designed to examine the cartilage protective and proliferative effects of Aralia cordata by using a collagenase-induced osteoarthritis (CIA) rabbit model.

MATERIALS AND METHODS

The right knees of rabbits were injected intra-articularly with collagenase, and rabbits were orally administered with distilled water (vehicle), Aralia cordata (200mg/kg) and celecoxib (100mg/kg) once a day for 28 days after the initiation of the CIA.

RESULTS

In histopathologic studying by using H&E and Safranin O staining, Aralia cordata showed a cartilage protective effect in CIA rabbit femoral condyle. However, celecoxib had no effect on cartilage protection in CIA. The inflammatory mediators involved in cartilage destruction, such as COX-2 and PGE(2), were inhibited in the Aralia cordata-treated group. Aralia cordata also showed an anti-apoptotic effect through suppression of caspase-3 activity and chondrocyte proliferation induction in both in vivo and in vitro.

CONCLUSION

These results indicate that Aralia cordata showed cartilage protective effects through the down-regulations of COX-2 expression, PGE(2) production, caspase-3 activity, and chondrocyte proliferation in the CIA rabbit model.

Protective effects of butanol fraction from Betula platyphyla var. japonica on cartilage alterations in a rabbit collagenase-induced osteoarthritis

AIM OF THIS STUDY

Many cartilage protective agents have been developed from natural products, and they have resulted in the development of treatments for osteoarthritis. In this study, we determined the osteoarthritic efficacy and mechanism of butanol fraction from the bark of Betula platyphylla var. japonica (BFBP) in collagenase-induced rabbit model of osteoarthritis (CIA).

MATERIALS AND METHODS

The right knees of rabbits were injected intra-articularly with collagenase, and rabbits were orally administrated with distilled water (vehicle), BFBP (50, 100 and 200 mg/kg) or celecoxib (100 mg/kg) once a day for 28 days after the initiation of the CIA.

RESULTS

Oral administration of BFBP dose-dependently suppressed the stiffness and global histologic score. Proteoglycan intensity was considerably increased in a dose-dependent manner. As well, the mRNA expression of MMP-1, and MMP-3 was decreased. On the contrary, the level of TIMP-1 in the synovial fluids was significantly increased in the BFBP treated group. The pathologic inflammatory molecules such as PGE2 and COX-2 were inhibited by BFBP, but COX-1 expression not affected.

CONCLUSION

We suggest that BFBP has shown the protective effect on cartilage alternations through balance of MMPs/TIMP-1 and regulates inflammatory-related molecules in vivo model of osteoarthritis, and great candidate for development of osteoarthritis treatment.

A protein with antiproliferative, antifungal and HIV-1 reverse transcriptase inhibitory activities from caper (Capparis spinosa) seeds

A protein exhibiting an N-terminal amino acid sequence with some similarity to imidazoleglycerol phosphate synthase was purified from fresh Capparis spinosa melon seeds. The purification protocol entailed anion exchange chromatography on DEAE-cellulose, cation exchange chromatography on SP-Sepharose, and finally gel filtration by fast protein liquid chromatography on Superdex 75. The protein was adsorbed using 20 mM Tris-HCl buffer (pH 7.4) and desorbed using 1 M NaCl in the starting buffer from the DEAE-cellulose column and SP-Sepharose column. The protein demonstrated a molecular mass of 38 kDa in gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that it was monomeric. The protein inhibited proliferation of hepatoma HepG2 cells, colon cancer HT29 cells and breast cancer MCF-7 cells with an IC(50) of about 1, 40 and 60 microM, respectively. It inhibited HIV-1 reverse transcriptase with IC(50) of 0.23 microM. It inhibited mycelial growth in the fungus, Valsa mali. It did not exhibit hemagglutinating, ribonuclease, mitogenic or protease inhibitory activities.

Benzo[d]isothiazol-3-yl-benzamidines: a Class of Protective Agents on Culture of Human Cartilage and Chondrocytes Stimulated by IL-1β

New derivatives of N-benzo[d]isothiazol-3-yl-benzamidine 6 a were synthesized as nonacidic anti-inflammatory/antidegenerative agents. We investigated the influence of the amidines 6 a-j on the production of NO, PGE(2), MMP-3, COX-2, ROS, and GAGs, key molecules involved in cartilage destruction in osteoarthritic diseases. The antidegenerative properties of the novel designed derivatives 6 b-j were improved with respect to N-benzo[d]isothiazol-3-yl-benzamidine 6 a. All of the compounds 6 a-j promoted the reduction of most of the IL-1beta-induced harmful effects. Derivatives 6 d, 6 h, and 6 j were the most potent of all the tested compounds, particularly in the human chondrocyte culture model.

A one-pot entry to a novel 3-H-benzo[d]pyrazolo[1,5-b]isothiazole ring system

The phosphorus ylide obtained from the reaction between 2-aminobenzo[d]isothiazol-3-one and dimethyl acetylenedicarboxylate in the presence of triphenylphosphine undergoes a smooth intramolecular Wittig-type reaction to produce, in a one-pot reaction, 3-H-benzo[d]pyrazolo[1,5-b]isothiazole-2,3a-dicarboxylic acid dimethyl ester, a novel functionalized heterocyclic compound.