AIMTo search for new derivatives of diclofenac (DC) having higher potency than the parent drug and lacking its undesirable effects.

METHODSCoupling DC with NO donor 3-hydroxymethyl-4-phenylfuroxan and its isomer through esterification, evaluating anti-inflammatory and analgesic activities, observing side effects in the rat gastrointestinal (GI) tract and assessing NO releasing ability both in vitro and in vivo.

RESULTSFifteen new compounds including nine target ones (II1-9) were synthesized, and their structures were determined by IR, 1HNMR, MS and elemental analysis. Compounds II3 and II9 showed anti-inflammatory activity comparable to DC. Compound II2 showed stronger anti-inflammatory and analgesic activities and less GI side effect than DC, and released NO in vivo.

CONCLUSIONCompound II2 is worthy to be intensively studied.

Analgesics ; chemical synthesis ; pharmacology ; therapeutic use ; Animals ; Anti-Inflammatory Agents, Non-Steroidal ; chemical synthesis ; pharmacology ; therapeutic use ; Cyclic N-Oxides ; administration & dosage ; chemistry ; pharmacology ; Diclofenac ; chemical synthesis ; pharmacology ; therapeutic use ; Digestive System ; drug effects ; Edema ; drug therapy ; Gastrointestinal Hemorrhage ; chemically induced ; Mice ; Molecular Structure ; Nitric Oxide ; metabolism ; Nitric Oxide Donors ; chemistry ; pharmacology ; Oxadiazoles ; administration & dosage ; chemistry ; pharmacology ; Pain Threshold ; drug effects ; Rats ; Structure-Activity Relationship

This study investigated whether tempol, an anti-oxidant, protects against renal injury by modulating phosphatidylinositol 3-kinase (PI3K)-Akt-Forkhead homeobox O (FoxO) signaling. Mice received unilateral ureteral obstruction (UUO) surgery with or without administration of tempol. We evaluated renal damage, oxidative stress and the expression of PI3K, Akt, FoxO3a and their target molecules including manganese superoxide dismutase (MnSOD), catalase, Bax, and Bcl-2 on day 3 and day 7 after UUO. Tubulointerstitial fibrosis, collagen deposition, alpha-smooth muscle actin-positive area, and F4/80-positive macrophage infiltration were significantly lower in tempol-treated mice compared with control mice. The expression of PI3K, phosphorylated Akt, and phosphorylated FoxO3a markedly decreased in tempol-treated mice compared with control mice. Tempol prominently increased the expressions of MnSOD and catalase, and decreased the production of hydrogen peroxide and lipid peroxidation in the obstructed kidneys. Significantly less apoptosis, a lower ratio of Bax to Bcl-2 expression and fewer apoptotic cells in TUNEL staining, and decreased expression of transforming growth factor-beta1 were observed in the obstructed kidneys from tempol-treated mice compared with those from control mice. Tempol attenuates oxidative stress, inflammation, and fibrosis in the obstructed kidneys of UUO mice, and the modulation of PI3K-Akt-FoxO3a signaling may be involved in this pathogenesis.
Animals ; Antioxidants/pharmacology/therapeutic use ; Collagen/metabolism ; Cyclic N-Oxides/*pharmacology/therapeutic use ; Fibrosis ; Forkhead Transcription Factors/*metabolism ; Hydrogen Peroxide/metabolism ; Kidney Diseases/drug therapy/metabolism/pathology ; Lipid Peroxidation ; Male ; Mice ; Mice, Inbred C57BL ; Oxidative Stress/drug effects ; Phosphatidylinositol 3-Kinases/*metabolism ; Phosphorylation/drug effects ; Proto-Oncogene Proteins c-akt/*metabolism ; Severity of Illness Index ; Signal Transduction/*drug effects ; Spin Labels ; Superoxide Dismutase/metabolism ; Ureteral Obstruction/complications/drug therapy/*metabolism/pathology