ABSTRACT
Schisandrol B (SolB) is one of the active constituents from a traditional Chinese medicine Schisandra chinensis or Schisandra sphenanthera. Our previous studies found that SolB exerts hepatoprotective effects against drug-induced liver injury and promotes liver regeneration. We further found that SolB significantly induces liver enlargement but the mechanisms remain unclear. The purpose of this study was to investigate the change of lipidome in liver tissues during SolB-induced hepatomegaly. The animal experiment protocol was approved by the Institutional Animal Care and Use Committee at Sun Yat-sen University. Serum and liver samples of male C57BL/6 mice were collected after intraperitoneal injection of SolB (100 mg·kg-1·d-1) for 5 days. Lipidomics analysis was performed using Q Exactive UHPLC-MS/MS system. The results showed that SolB significantly promoted liver enlargement in mice without liver injury and inflammation. Lipid accumulation was observed in the liver tissues after SolB treatment. Thirty-five lipids were identified with significant change and triglycerides (TG) were found to have the most significant increase in SolB-treated group, indicating the increase of energy production during SolB-induced hepatomegaly. This study reveals the impact of SolB on lipid metabolism and provides a potential explanation for liver enlargement induced by SolB.
ABSTRACT
Cyclophosphamide (CPA) is one of the most commonly used alkylating agents in the treatment of malignant cancer. CPA is metabolized by cytochrome P450 enzymes into 4-hydroxycyclophosphamide in vivo which can exhibit anti-tumor activity. Metabolic activation of CPA can cause adverse reactions such as myelosuppression, cystitis, and liver injury. The aim of this study was to evaluate the dynamic changes of hepatic injury induced by CPA in mice. Male BALB/c mice were injected CPA (200 mg·kg-1) intraperitoneally. Both serum and liver samples were collected at 0, 2, 6, 12 and 24 hours after dosing. The animal experiment protocol was approved by the Institutional Animal Care and Use Committee at Sun Yat-sen University. The results showed that hepatotoxicity was observed at 2 hours after CPA dosing, and the most serious liver injury was measured at 12 hours. The level of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and malondialdehyde (MDA) was significantly increased, glutathione (GSH) level was significantly decreased, hepatocyte edema and vacuolar degeneration were widely observed in liver tissue, and began to recover 24 hours after dosing. In addition, due to oxidative stress damage caused by CPA, nuclear factor-erythroid 2-related factor 2 (NRF2) signaling pathway was activated and the mRNA and protein expression of its downstream targets such as quinine oxidoreductase 1 (NQO1), heme oxygenase-1 (HO-1), glutamate-cysteine ligase catalytic subunit (GCLC) and glutamate cysteine modifier subunit (GCLM) were up-regulated, which alleviated oxidative stress injury. In a summary, this study demonstrate the dynamic change of CPA-induced liver injury and the NRF2-mediated protective mechanisms, providing new insights into the CPA-induced liver injury.