OBJECTIVETo investigate the renal protective effect of sodium ferulate magnetic nanoparticle targeting therapy in septic rats receives norepinephrine treatment.

METHODSFirst we constructed sodium ferulate magnetic nanoparticle, Wistar male rats were randomly divided into 4 groups (n = 6): control group, septic group, norepinephrine treatment group (NE treatment group) and NE plus sodium ferulate magnetic nanoparticle treatment group (NE + SF group), septic rat model was reproduced by intravenous injection of lipolysaccharide (IPS) in rats in NE treatment group norepinephrine were used to elevate the blood pressure of septic rats, in NE + SF group sodium ferulate magnetic nanoparticle was injected via tail vein, magnetic field was placed near renal region. Urinary concentration of N-acetyl-beta-D-glucosaminidase (NAG), kidney injury molecule (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL), renal tissue concentration of malonaldehyde (MDA), superoxide dismutase (SOD), and serum concentration of blood urea nitrogen (BUN), creatinine (Cr), alanine aminotransferase (ALT), aspartate aminotransferase (AST) were measured 3 hours after treatment.

RESULTSAfter injected LPS via tail vein, systolic blood pressure, pH value, PaO2 and PaCO2 of arterial blood of septic rats decreased significantly. Systolic blood pressure, pH value, PaO2 and PaCO2 of arterial blood returned to baseline approximately after norepinephrine treatment, sodium ferulate magnetic nanoparticle targeting therapy did not change hemodynamic effects of norepinephrine. Compared with control group, urine NAG, KIM-1 and NGAL of sepsis group were increased significantly (P < 0.01), after treatment with norepinephrine, urine NAG, KIM-1 and NGAL of NE treatment group were elevated rapidly compared with those of sepsis group (P < 0.01), combined with sodium ferulate magnetic nanoparticles targeting treatment, urine NAG, KIM-1 and NGAL of NE + SF group were decreased significantly compared with those of sepsis group and NE treatment group (P < 0.01). Compared with control group, renal tissue MDA levels of septic rats increased significantly (P < 0.01), NE treatment could notably raise MDA levels compared with those of sepsis group (P < 0.01), renal tissue MDA levels of NE + SF group were decreased significantly compared with those of sepsis group and NE treatment group (P < 0.01). Compared with control group, renal tissue activities of SOD of sepsis group and NE treatment group were decreased significantly (P < 0.01), after targeted treatment with sodium ferulate magnetic nanoparticle, renal tissue SOD activities of NE + SF group increased significantly compared with those of sepsis group and NE treatment group (P < 0.01 vs sepsis group and NE treatment group). Serum BUN, Cr, ALT, AST levels did not significantly change in each groups.

CONCLUSIONSodium ferulate magnetic nanoparticle targeting therapy can effectively decrease urine NAG, KIM-1, NGAL and renal tissue MDA level, increase tissue SOD activity of sepsis group and NE treatment group rats, thus protect renal function of septic rats.