Study on the pharmacokinetics, tissue distribution and excretion of Penthorum chinense Pursh in normal and acute alcoholic liver injury rats using validated UPLC-MS/MS method.

Penthorum chinense Pursh (PCP), as a traditional medicine of Miao nationality in China, is often used for the treatment of various liver diseases. At present, information regarding the in vivo process of PCP is lacking. Herein, a sensitive and robust ultra-performance liquid chromatography tandem with mass spectrometry (UPLC-MS/MS) was developed and validated for the quantification of several components to study their pharmacokinetics, tissues distribution and excretion in normal and acute alcoholic liver injury (ALI) rats. Prepared samples were separated on a Thermo C18 column (4.6 mm × 50 mm, 2.4 µm) using water containing 0.1 % formic acid (A) and acetonitrile (B) as the mobile phase for gradient elution. Negative electrospray ionization was performed using multiple reaction monitoring (MRM) mode for each component. The validated UPLC-MS/MS assay gave good linearity, accuracy, precision, recovery rate, matrix effect and stability. This method was successfully applied to the pharmacokinetics, tissue distribution and excretion in normal and acute ALI rats. There were differences in pharmacokinetic process, tissue distribution and excretion characteristics, indicating that ALI had a significant influence on the in vivo process of PCP in rats. The research provided an experimental basis for the study of PCP quality control and further application in the clinic.

[Curcumin alleviates nuclear factor-κB/NOD-like receptor protein 3 mediated renal injury caused by acute respiratory distress syndrome through reducing mitochondrial oxidative stress].

OBJECTIVE: To evaluate the effect of curcumin on renal mitochondrial oxidative stress, nuclear factor-κB/NOD-like receptor protein 3 (NF-κB/NLRP3) inflammatory body signaling pathway and tissue cell injury in rats with acute respiratory distress syndrome (ARDS). METHODS: A total of 24 specific pathogen free (SPF)-grade healthy male Sprague-Dawley (SD) rats were randomly divided into control group, ARDS model group, and low-dose and high-dose curcumin groups, with 6 rats in each group. The ARDS rat model was reproduced by intratracheal administration of lipopolysaccharide (LPS) at 4 mg/kg via aerosol inhalation. The control group was given 2 mL/kg of normal saline. The low-dose and high-dose curcumin groups were administered 100 mg/kg or 200 mg/kg curcumin by gavage 24 hours after model reproduction, once a day. The control group and ARDS model group were given an equivalent amount of normal saline. After 7 days, blood samples were collected from the inferior vena cava, and the levels of neutrophil gelatinase-associated lipocalin (NGAL) in serum were determined by enzyme-linked immunosorbent assay (ELISA). The rats were sacrificed, and kidney tissues were collected. Reactive oxygen species (ROS) levels were determined by ELISA, superoxide dismutase (SOD) activity was detected using the xanthine oxidase method, and malondialdehyde (MDA) levels were determined by colorimetric method. The protein expressions of hypoxia-inducible factor-1α (HIF-1α), caspase-3, NF-κB p65, and Toll-like receptor 4 (TLR4) were detected by Western blotting. The mRNA expressions of HIF-1α, NLRP3, and interleukin-1ß (IL-1ß) were detected by reverse transcription-polymerase chain reaction (RT-PCR). Renal cell apoptosis was detected by TdT-mediated dUTP nick end labeling (TUNEL). The morphological changes in renal tubular epithelial cells and mitochondria were observed under a transmission electron microscope. RESULTS: Compared with the control group, the ARDS model group exhibited kidney oxidative stress and inflammatory response, significantly elevated serum levels of kidney injury biomarker NGAL, activated NF-κB/NLRP3 inflammasome signaling pathway, increased kidney tissue cell apoptosis rate, and renal tubular epithelial cell damage and mitochondrial integrity destruction under transmission electron microscopy, indicating successful induction of kidney injury. Following curcumin intervention, the injury to renal tubular epithelial cells and mitochondria in the rats was significantly mitigated, along with a noticeable reduction in oxidative stress, inhibition of the NF-κB/NLRP3 inflammasome signaling pathway, and a significant decrease in kidney tissue cell apoptosis rate, demonstrating a certain dose-dependency. Compared with the ARDS model group, the high-dose curcumin group exhibited significantly reduced serum NGAL levels and kidney tissue MDA and ROS levels [NGAL (µg/L): 13.8±1.7 vs. 29.6±2.7, MDA (nmol/g): 115±18 vs. 300±47, ROS (kU/L): 75±19 vs. 260±15, all P < 0.05], significantly down-regulated protein expressions of HIF-1α, caspase-3, NF-κB p65, and TLR4 in the kidney tissue [HIF-1α protein (HIF-1α/ß-actin): 0.515±0.064 vs. 0.888±0.055, caspase-3 protein (caspase-3/ß-actin): 0.549±0.105 vs. 0.958±0.054, NF-κB p65 protein (NF-κB p65/ß-actin): 0.428±0.166 vs. 0.900±0.059, TLR4 protein (TLR4/ß-actin): 0.683±0.048 vs. 1.093±0.097, all P < 0.05], and significantly down-regulated mRNA expressions of HIF-1α, NLRP3, and IL-1ß [HIF-1α mRNA (2-ΔΔCt): 2.90±0.39 vs. 9.49±1.87, NLRP3 mRNA (2-ΔΔCt): 2.07±0.21 vs. 6.13±1.32, IL-1ß mRNA (2-ΔΔCt): 1.43±0.24 vs. 3.95±0.51, all P < 0.05], and significantly decreased kidney tissue cell apoptosis rate [(4.36±0.92)% vs. (27.75±8.31)%, P < 0.05], and significantly increased SOD activity (kU/g: 648±34 vs. 430±47, P < 0.05). CONCLUSIONS: Curcumin can alleviate kidney injury in ARDS rats, and its mechanism may be related to the increasing in SOD activity, reduction of oxidative stress, and inhibition of the activation of the NF-κB/NLRP3 inflammasome signaling pathway.