Potentiometric and spectroscopic studies on the solution molecular structures of copper(II)-[S]-2-[N-(2′-hydroxybenzyl)aminomethyl]pyrrolidine complexes, potential non-steroidal anti-inflammatory agents (NSAIDs)

The purpose of this study was to investigate the complexes formed by copper(II) with potential non-steroidal anti-inflammatory agents (NSAIDs) under physiological conditions. A former study suggested that 2-benzylaminomethylpyrrolidine ligands could be good candidates as potential OIL (OH-inactivating ligand) when complexed to copper(II). In order to assess the chemical behavior as OIL, [S]-2-[N-(2′-hydroxybenzyl)aminomethyl]pyrrolidine (OHbamp) was synthesized and bound to copper(II). Physico-chemical properties were determined at 37 °C in 0.15 M NaCl using glass electrode potentiometry, UV-Vis and circular dichroism spectroscopies, before and after copper(II) complexation. [Cu(OHbamp)(H₂O)₃]⁺ was the main complex found at both physiological and inflammatory pH values, showing appreciable stability at pathological pH compared to copper(II) complexes of histidine, the predominant low-molar-mass ligand of copper(II) in blood plasma. However, neutral species such as [Cu(OHbamp)₂(H₂O)₂] and [Cu(OHbamp)(OH)(H₂O)₃] are predominant only above pH 8, preventing a significant amount of drug from diffusing through membranes at inflammatory pH. In conclusion, copper(II)-OHbamp system does not meet all the requirements to be an OIL. Nevertheless, these results allow us to better identify the chemical features needed for a good OIL candidate.     

Interaction of nonsteroidal anti-inflammatory drugs with membranes: In vitro assessment and relevance for their biological actions

Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most commonly used drugs in the world due to their anti-inflammatory, analgesic and antipyretic properties. Nevertheless, the consumption of these drugs is still associated with the occurrence of a wide spectrum of adverse effects. Regarding the major role of membranes in cellular events, the hypothesis that the biological actions of NSAIDs may be related to their effect at the membrane level has triggered the in vitro assessment of NSAIDs-membrane interactions. The use of membrane mimetic models, cell cultures, a wide range of experimental techniques and molecular dynamics simulations has been providing significant information about drugs partition and location within membranes and also about their effect on diverse membrane properties. These studies have indeed been providing evidences that the effect of NSAIDs at membrane level may be an additional mechanism of action and toxicity of NSAIDs. In fact, the pharmacokinetic properties of NSAIDs are closely related to the ability of these drugs to interact and overcome biological membranes. Moreover, the therapeutic actions of NSAIDs may also result from the indirect inhibition of cyclooxygenase due to the disturbing effect of NSAIDs on membrane properties. Furthermore, increasing evidences suggest that the disordering effects of these drugs on membranes may be in the basis of the NSAIDs-induced toxicity in diverse organ systems. Overall, the study of NSAIDs-membrane interactions has proved to be not only important for the better understanding of their pharmacological actions, but also for the rational development of new approaches to overcome NSAIDs adverse effects.     

Interactions of sulindac and its metabolites with phospholipid membranes: An explanation for the peroxidation protective effect of the bioactive metabolite

Non-steroidal anti-inflammatory drugs (NSAIDs) treat inflammatory processes by inhibition of cycloxygenase (COX). However, their action against lipid peroxidation can be an alternative pathway to COX inhibition. Since inflammation and lipid peroxidation are cell-surface phenomena, the effects of NSAIDs on membrane models were investigated. Peroxidation was induced by peroxyl radical (ROO?) derived from AAPH and assessed in aqueous or lipid media using fluorescence probes with distinct lipophilic properties: fluorescein; HDAF and DPH-PA. The antioxidant effect of Sulindac and its metabolites was tested and related with their membrane interactions. Drug–membrane interactions included the study of: drug location by fluorescence quenching; drug interaction with membrane surface by zeta-potential measurements; and membrane fluidity changes by steady-state anisotropy. Results revealed that the active NSAID (sulindac sulphide) penetrates into the lipid bilayer and protects the membrane against oxy-radicals. The inactive forms (sulindac and sulindac sulphone) present weaker interactions with the membrane and are better radical scavengers in aqueous media.     

布洛芬微生物降解研究进展

布洛芬是苯丙酸类非甾体类抗炎药物的典型代表,属于重要的药物及个人护理品类物质。大量生产和广泛使用的布洛芬在为人类减轻病痛的同时,也带来诸多环境污染危害,已经成为重要潜在环境污染物之一。本文简要介绍布洛芬的使用情况和环境中布洛芬残留的潜在风险,重点总结布洛芬的微生物降解及降解机理研究,提出应当关注污水、脱水污泥、河流沉积物和湿地中布洛芬的微生物降解,强调开展布洛芬降解基因克隆和功能分析以及从分子水平阐明布洛芬降解机理研究的必要性及紧迫性。     

NSAIDS inhibit in vitro MSC chondrogenesis but not osteogenesis: implications for mechanism of bone formation inhibition in man

The non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for analgesia but may inhibit bone formation. We investigated whether the reported NSAID effect on bone is related to inhibition of bone marrow mesenchymal stem cell (MSC) proliferation and osteogenic and chondrogenic differentiation and evaluated both cyclooxygenase (COX)-1 and COX-2 specific drugs. The effects of seven COX-1 and COX-2 inhibitors on MSC proliferation and osteogenic and chondrogenic differentiation were tested using Vybrant, sodium 3′-[1-(phenylaminocarbonyl)- 3,4-tetrazolium]-bis (4-methoxy-6-nitro) benzene sulfonic acid hydrate (XTT), functional and quantitative assays of MSC differentiation. The MSC expression of COX-1 and COX-2 and prostaglandin E2 (PGE-2) levels were evaluated serially during lineage differentiation by quantitative PCR and ELISA. None of the NSAIDs at broad range of concentration (range 10⁻³ to 100 μg/ml) significantly affected MSC proliferation. Surprisingly, MSC osteogenic differentiation inhibition was not evident. However, NSAIDs affected chondrogenic potential with a reduction in sulphated glycosaminoglycans (sGAG) content by 45% and 55% with diclofenac and ketorolac, respectively (P < 0.05 compared to controls). Parecoxib and meloxicam, more COX-2 specific reagents inhibited sGAG to a lesser degree, 22% and 27% respectively (P < 0.05 compared to controls). Cartilage pellet immunohistochemistry confirmed the above results. Pellet chondrogenesis was associated with increased COX-1 expression levels but not COX-2, and COX-1 specific drugs suppressed MSC PGE-2 more than COX-2 specific inhibitors. These findings suggest that NSAIDs may inhibit bone formation via blockage of MSC chondrogenic differentiation which is an important intermediate phase in normal endochondral bone formation.     

Obovatol attenuates LPS-induced memory impairments in mice via inhibition of NF-κB signaling pathway

Neuroinflammation and accumulation of β-amyloid are critical pathogenic mechanisms of Alzheimer’s disease (AD). In the previous study, we have shown that systemic lipopolysaccharide (LPS) caused neuroinflammation with concomitant increase in β-amyloid and memory impairments in mice. In an attempt to investigate anti-neuroinflammatory properties of obovatol isolated from Magnolia obovata, we administered obovatol (0.2, 0.5 and 1.0 mg/kg/day, p.o.) to animals for 21 days before injection of LPS (0.25 mg/kg, i.p.). We found that obovatol dose-dependently attenuates LPS-induced memory deficit in the Morris water maze and passive avoidance tasks. Consistent with the results of memory tasks, the compound prevented LPS-induced increases in Aβ_1-42 formation, β- and γ-secretases activities and levels of amyloid precursor protein, neuronal β-secretase 1 (BACE1), and C99 (a product of BACE1) in the cortex and hippocampus. The LPS-mediated neuroinflammation as determined by Western blots and immunostainings was significantly ameliorated by the compound. Furthermore, LPS-induced nuclear factor (NF)-κB DNA binding activity was drastically abolished by obovatol as shown by the electrophoretic mobility shift assay. The anti-neuroinflammation and anti-amyloidogenesis by obovatol were replicated in in vitro studies. These results show that obovatol mitigates LPS-induced amyloidogenesis and memory impairment via inhibiting NF-κB signal pathway, suggesting that the compound might be plausible therapeutic intervention for neuroinflammation-related diseases such as AD.     

NO-NSAIDs: Gastric-sparing nitric oxide-releasable prodrugs of non-steroidal anti-inflammatory drugs

Recently, a new class of nitric-oxide-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) is being studied as ‘Safe NSAIDs’ because of their gastric-sparing properties. As an extension of our novel disulfide linker technology, we have designed, synthesized and evaluated novel NO-releasing NSAID prodrugs such as NO-Aspirin (1b–d) and NO-Diclofenac (2b–c). Although the amide-containing derivative 1d did not show any bioavailability, the remaining compounds have shown fair to excellent pharmacokinetic, anti-inflammatory and gastric-sparing properties. Among them, however, the NO-Diclofenac (2b) has shown the most promising pharmacokinetic, anti-inflammatory and NO-releasing properties and protected rats from NSAID-induced gastric damage which could be attributable to the beneficial effects of NO released from these prodrugs.