The selective cyclooxygenase-2 (COX-2) and 5-lipoxygenase (LOX) inhibitors might inhibit prostaglandin synthesis and reduce proteinuria. The present study was designed to investigate the anti-proteinuric effects of nordihydroguaiaretic acid (NDGA) as compared with celecoxib in puromycin aminonucleoside (PAN) nephrosis rats. Fifty five male Sprague-Dawley rats were divided into 4 groups; A, normal control; B, PAN group; C, PAN+COX-2 inhibitor (celecoxib) group; and D, PAN+5-LOX inhibitor (NDGA) group. After induction of PAN nephrosis through repeated injections of PAN (7.5 and 15 mg/100 g body weight), rats were treated with celecoxib, NDGA, or vehicle for 2 weeks. Twenty four hour urine protein excretions were significantly lower in PAN+celecoxib and PAN+NDGA groups than in PAN group. Serum creatinine (SCr) concentrations and 24 hr urine creatinine clearances (CCr) were not significantly different in the four groups. Electron microscopy showed that podocyte morphology was changed after the induction of PAN nephrosis and was recovered after celecoxib or NDGA administration. Celecoxib significantly recovered the expressions of nephrin, CD2AP, COX-2, and TGF-beta. NDGA also recovered TGF-betaexpression, but did not alter the expressions of nephrin, CD2AP and COX-2. The present study suggested that celecoxib and NDGA might effectively reduce proteinuria in nephrotic syndrome without impairing renal function.
Animals ; Anti-Inflammatory Agents, Non-Steroidal/pharmacology ; Body Weight ; Creatinine/blood ; Cyclooxygenase Inhibitors/pharmacology ; Male ; Microscopy, Electron ; Nephrosis/*chemically induced/drug therapy ; Nordihydroguaiaretic Acid/*pharmacology ; Podocytes/metabolism ; Puromycin Aminonucleoside/pharmacology/*toxicity ; Pyrazoles/*pharmacology ; Rats ; Rats, Sprague-Dawley ; Sulfonamides/*pharmacology ; Time Factors

Reactive oxygen species (ROS) performs a pivotal function as a signaling mediator in receptor-mediated signaling. However, the sources of ROS in this signaling have yet to be determined, but may include lipoxygenases (LOXs) and NADPH oxidase. The stimulation of lymphoid cells with TNF-alpha, IL-1beta, and LPS resulted in significant ROS production and NF-kappaB activation. Intriguingly, these responses were markedly abolished via treatment with the LOXs inhibitor nordihydroguaiaretic acid (NDGA). We further examined in vivo anti-inflammatory effects of NDGA in allergic airway inflammation. Both intraperitoneal and intravenous NDGA administration attenuated ovalbumin (OVA)-induced influx into the lungs of total leukocytes, as well as IL-4, IL-5, IL-13, and TNF-alpha levels. NDGA also significantly reduced serum levels of OVA-specific IgE and suppressed OVA-induced airway hyperresponsiveness to inhaled methacholine. The results of our histological studies and flow cytometric analyses showed that NDGA inhibits OVA-induced lung inflammation and the infiltration of CD11b+ macrophages into the lung. Collectively, our findings indicate that LOXs performs an essential function in pro-inflammatory signaling via the regulation of ROS regulation, and also that the inhibition of LOXs activity may have therapeutic potential with regard to the treatment of allergic airway inflammation.
Animals ; Antioxidants/metabolism ; Asthma/complications/metabolism/pathology/physiopathology ; Bronchial Hyperreactivity/drug therapy/pathology ; Bronchial Provocation Tests ; Bronchoalveolar Lavage Fluid/cytology ; Cells, Cultured ; Drug Evaluation, Preclinical ; Humans ; Inflammation/*etiology/metabolism ; Jurkat Cells ; Lipoxygenase/*physiology ; Lipoxygenase Inhibitors/pharmacology/therapeutic use ; Lymphocytes/drug effects/metabolism ; Male ; Mice ; Mice, Inbred BALB C ; Nordihydroguaiaretic Acid/pharmacology/therapeutic use ; Reactive Oxygen Species/*adverse effects/*metabolism