ABSTRACT
Objective:To explore the effect of celastrol in inhibiting the lipid metabolism disorder in hepatic L02 cells and its possible mechanism on endoplasmic reticulum stress (ERS) of non-alcoholic fatty liver cells by intervening non-alcoholic fatty liver disease(NAFLD) cell model with celastrol. Method:Hepatic L02 cells were divided into control group, model group, low-dose celastrol treatment group (Cel 0.5 mg·L-1), high-dose celastrol treatment group (Cel 1 mg·L-1) and simvastatin group (SIM 6 mg·L-1) for cultivation. The contents of total cholesterol (TC) and total triglyceride (TG) in hepatic L02 cells were detected, and the oil red staining was used to detected the lipid accumulation in hepatic L02 cells. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to detect the mRNA and protein expression levels of endoplasmic reticulum stress (ERS)-related signal molecules activating transcription factor 6 (ATF6), glucose regulated protein 78 (GRP78), inositol-requiring enzyme 1 (IRE1), sterol regulatory element-binding protein cleavage-activating protein (SCAP), sterol regulatory element-binding protein-1c (SREBP-1c) and sterol regulatory element-binding protein-2 (SREBP-2) in hepatic L02 cell model respectively. Result:The contents of TC and TG in hepatic L02 cells of NAFLD group were significantly higher than those in control group (P-1 group, Cel 1 mg·L-1 group and SIM 6 mg·L-1 group were significantly lower than those in NAFLD group (P-1 group, the Cel 1 mg·L-1 group, and the SIM 6 mg·L-1 group were lower than the NAFLD group to different degrees. According to the results of RT-PCR and Western blot, the mRNA transcription and protein expression levels of ERS-related signaling molecules ATF6, GRP78, IRE1, SCAP, SREBP-1c and SREBP-2 in hepatic L02 cells of NAFLD group were higher than those of control group (P-1 group, Cel 1 mg·L-1 group and SIM 6 mg·L-1 group were lower than those of NAFLD group (P-1 group and the SIM 6 mg·L-1 group. Conclusion:Celastrol can reduce the lipid metabolism disorder in hepatic L02 cells by down-regulating the expressions of ERS-related signaling molecules ATF6, GRP78, IRE1, SCAP, SREBP-1c and SREBP-2 in hepatic L02 cells, so as to improve NAFLD.
ABSTRACT
PURPOSE: To examine the cognition, spontaneous epilepsy, and electroencephalography (EEG) characteristics of rats with malformations of cortical development (MCD) and their use as an animal model for investigating the pathogenesis of intractable epilepsy and screening novel antiepileptic drugs. METHODS: An epileptic rat model of MCD was established with the F1 generation of pregnant rats after X-irradiation with 175 cGy (Group L), 195 cGy (Group M), or 215 cGy (Group H). Long-term video-EEG monitoring was used to record the seizures in the rats with MCD. Cognition was assessed with the Morris water maze. The EEGs were recorded and analyzed in the frontal and parietal lobes and hippocampi of adult rats. Finally, the brain tissues were processed for Nissl staining. RESULTS: The model groups exhibited markedly prolonged escape latencies and distinct decrements in the percent distance traveled in the target quadrant and platform-crossing frequency. These findings were dose-dependent. Frequent interictal epileptiform discharges were observed in the frontal and parietal lobes and hippocampi of adult rats, and their incidences were markedly higher in the model groups compared with that in the normal controls, with Group M having the highest incidence. Spontaneous seizures were observed in the model groups (mean incidence, 46.7%). The daily mean frequency of seizures and the incidence of spontaneous seizures were highest in Group M. Nissl staining revealed a dose-dependent pattern of hippocampal abnormalities, cortical and subcortical nodular heterotopia, and callosal agenesis in the model groups. CONCLUSION: The 195 cGy dose was most appropriate for establishing an epileptic model of MCD with X-irradiation.
