Neng-Jing-Huo Essential Oil Blend Inhibits Lipopolysaccharide-Induced Intracellular Reactive Oxygen Species Accumulation, Inflammation, and Apoptosis in Renal Tubular Epithelial Cells.

Abstract

Abstract: Acute kidney injury (AKI) is a common serious complication of sepsis that is characterized by the rapid deterioration of kidney function. Neng-Jing-Huo (NJH) is an essential oil blend, including Gaultheria procumbens, Zingiber officinale, Bulnesia sarmientoi, Artemisia vulgaris , and Styrax benzoin oils, with antimicrobial, antioxidant, and anti-inflammatory activities. Here, we investigated the effects of NJH on oxidative stress, inflammatory response, and apoptosis in an in vitro septic AKI model and explored the underlying mechanisms. A cellular model of septic AKI was established using lipopolysaccharide (LPS). Cell viability was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Action mechanisms of NJH were analyzed using the Griess reagent, 2',7'-dichlorodihydrofluorescein diacetate, 5,5',6,6' tetrachloro-1,1'3,3' tetraethylbenzimidazolcarbocyanine iodide, annexin V, caspase activity, western blotting, and semi-quantitative reverse transcription polymerase chain reaction assays. Results showed that pretreatment with NJH significantly improved cell survival and suppressed nitric oxide (NO) production in LPS-stimulated NRK-52E renal tubular epithelial cells. NJH also decreased the levels of intracellular reactive oxygen species and maintained the mitochondrial membrane potential by upregulating the nuclear factor (NF) erythroid 2-related factor 2/heme oxygenase-1 levels and downregulating the NADPH oxidase 4 levels. In addition, NJH suppressed the activation of the toll-like receptor 4/NF-κB and NLRP3/caspase-1 pathways, thereby decreasing the inflammatory response in LPS-stimulated NRK-52E cells. Moreover, NJH decreased the levels of Bax, caspase-9, and caspase-3 but increased those of Bcl-2, which led to a reduction in LPS-induced apoptosis. Overall, our findings revealed that NJH ameliorated LPS-induced damage in NRK-52E cells by inhibiting oxidative stress, inflammation, and apoptosis, highlighting its therapeutic potential for septic AKI.