The deubiquitinating enzyme 13 retards non-alcoholic steatohepatitis via blocking inactive rhomboid protein 2-dependent pathway

Nowadays potential preclinical drugs for the treatment of nonalcoholic steatohepatitis (NASH) have failed to achieve expected therapeutic efficacy because the pathogenic mechanisms are underestimated. Inactive rhomboid protein 2 (IRHOM2), a promising target for treatment of inflammation-related diseases, contributes to deregulated hepatocyte metabolism-associated nonalcoholic steatohepatitis (NASH) progression. However, the molecular mechanism underlying Irhom2 regulation is still not completely understood. In this work, we identify the ubiquitin-specific protease 13 (USP13) as a critical and novel endogenous blocker of IRHOM2, and we also indicate that USP13 is an IRHOM2-interacting protein that catalyzes deubiquitination of Irhom2 in hepatocytes. Hepatocyte-specific loss of the Usp13 disrupts liver metabolic homeostasis, followed by glycometabolic disorder, lipid deposition, increased inflammation, and markedly promotes NASH development. Conversely, transgenic mice with Usp13 overexpression, lentivirus (LV)- or adeno-associated virus (AAV)-driven Usp13 gene therapeutics mitigates NASH in 3 models of rodent. Mechanistically, in response to metabolic stresses, USP13 directly interacts with IRHOM2 and removes its K63-linked ubiquitination induced by ubiquitin-conjugating enzyme E2N (UBC13), a ubiquitin E2 conjugating enzyme, and thus prevents its activation of downstream cascade pathway. USP13 is a potential treatment target for NASH therapy by targeting the Irhom2 signaling pathway.

Degrade naphthalene using cells immobilized combining with low-intensity ultrasonic technique.

In this paper, we studied the naphthalene degradation by using Pseudomonas aeruginosa under low-intensity ultrasonic stimulation. In our experiment, the degradation rate of naphthalene was the main parameter. We found that low-intensity ultrasonic could not only promote the growth of immobilized P. aeruginosa, but also could improve the degradation of naphthalene. In this article, 1% naphthalene was added into MM culture medium as imitation wastewater. The effect of low-intensity ultrasonic parameter and gel-globes size were considered. We found the influence was obvious, and the optimum degradation rate was acquired when the parameters of ultrasonic are: frequency, 24 kHz; power, 8 W; ultrasonic time, interval time, 10 s; total time, 10 m and the gel-globes were made by using injector no. 14. The naphthalene degradation rate of immobilized cells with ultrasonic stimulation is 82%, which is 12.9 and 42.2% higher than that of immobilized cells and suspended cells without ultrasonic stimulation, respectively.

Hydrolytic cleavage of DNA by quercetin manganese(II) complexes.

Quercetin manganese(II) complexes were investigated focusing on its DNA hydrolytic activity. The complexes successfully promote the cleavage of plasmid DNA, producing single and double DNA strand breaks. The amount of conversion of supercoiled form (SC) of plasmid DNA to the nicked circular form (NC) depends on the concentration of the complex as well as the duration of incubation of the complexes with DNA. The maximum rate of conversion of the supercoiled form to the nicked circular form at pH 7.2 in the presence of 100 microM of the complexes is found to be 1.32 x 10(-4) s(-1). The hydrolytic cleavage of DNA by the complexes was supported by the evidence from free radical quenching, thiobarbituric acid-reactive substances (TBARS) assay and T4 ligase ligation.

Hydrolytic cleavage of DNA by quercetin zinc(II) complex.

Quercetin zinc(II) complex was investigated focusing on its hydrolytic activity toward DNA. The complex successfully promotes the cleavage of plasmid DNA, producing single and double DNA strand breaks. The amount of conversion of supercoiled form (SC) of plasmid to the nicked circular form (NC) depends on the concentration of the complex as well as the duration of incubation of the complex with DNA. The rate of conversion of SC to NC is 1.68x10(-4) s(-1) at pH 7.2 in the presence of 100 microM of the complex. The hydrolytic cleavage of DNA by the complex is supported by the evidence from free radical quenching, thiobarbituric acid-reactive substances (TBARS) assay, and T4 ligase ligation.

Primary study on the application of Serum Pharmacology in Chinese traditional medicine.

In the paper, two main methods, which are Serum Pharmacology and Traditional Pharmacology, were adopted to study Chinese traditional medicine, such as Ginkgo biloba extract (GBE), ginsenosides (GS) and compound GG (GBE+GS), pharmacology in vitro. The results showed that there were evident difference between the results of Serum Pharmacology and that of Traditional Pharmacology. There was no significant difference between the drug effect of crude GS on nitric oxide (NO) production in ECV304 and that of crude GBE, and the drug effect of GG was superior to that of GS and GBE, respectively. But, compared with GBE serum, the GS serum up-regulation of NO production in ECV304 increased significantly, and the GG serum up-regulation of the NO production in ECV304 was inferior to that of GS serum and GBE serum significantly. The results suggested that Serum Pharmacological study should be adopted in the pharmacological investigation on the Chinese traditional medicine and the drug screening of the Chinese traditional medicine.

Effect of compatibility on the pharmacokinetic characteristics of ginsenosides.

Pharmacokinetic research, which is one of the most important parts of preclinic research, plays an important role in guiding medicine compatibility and preparation improvement. In this paper, the influence of the compatibility of GGV on pharmacokinetics of ginsenosides (GS) was studied, which consisted of ginsenosides, ginkgo biloba extract (GBE) and a chemical monomer V. The result indicated that the addition of either GBE or V could influence the pharmacokinetic parameters of ginsenosides and the influence was different when different administering routes were adopted. Therefore, it could be concluded that there are interactions among GS, GBE and V, and the synergetic and inhibitory effects of the three ingredients contribute to the pharmacological effect of GGV.

Investigation on the effects of diamide on NO production in vascular endothelial cells (VEC).

Nitric oxide (NO) controls several physiological functions of the cardiovascular system. The study on the effect of diamide (N(2)H(4).H(2)O) on NO production in vascular endothelial cells (VEC) may provide significant reference for VEC's modeling in studying cardiovascular diseases. The objective of this study was to elucidate how high concentration diamide (V(diamide)/V(culture miedium) = 5 ml/l) and low concentration diamide (V(diamide)/V(culture miedium) = 0.5 ml/l) affect NO production in a human endothelial cell line (ECV304). After cells were incubated with diamide (5 or 0.5 ml/l) for 4, 6, 8 or 10h, respectively, the amounts of NO metabolites released by the cells were quantitated and the degree of damage of VEC was observed using microscope. The results showed that NO production in VEC tended to decrease with the lapse of time in the 0.5 ml/l diamide group. In the 5 ml/l diamide group, on the contrary, NO production in VEC tended to increase with the lapse of time. At the same time, from the morphologic observation, the VEC were damaged severely after treated with 5 ml/l diamide. So it could be concluded that the severe damage induced by high concentration diamide would have triggered the express of inducible nitric oxide synthases (iNOS). Just for the expresssion of iNOS, NO production in VEC treated with high concentration diamide occurred abnormally in contrast to the 0.5 ml/l group.

Survivin and Bcl-2 modulate apoptosis in A549 cell induced by quercetin / 中国药理学通报

Aim To investigate the apoptosis of lung cancer cells A549 induced by quercetin and the regulation of survivin and Bcl-2 on A549 cells induced by quercetin.Methods MTT,fluorescence stain,flow cytometric analysis and immunocytochemistry stain were carried out.Results Quercetin had a significant inhibition on growth and proliferation of A549 cell in a concentration-and time-dependent manner.Evidence was provided that apoptosis occurred in A549 cells treated with quercetin using fluorescence microscopy.Quercetin arrested A549 cells at the G0/G1 phase by FCM analyses.Expression of survivin and Bcl-2 protein were decreased,and activity of caspase-3 were enhanced.Conclusion Quercetin could induce apoptosis of A549 cells.The arrested cell cycle and the down-regulation of survivin and Bcl-2 protein could activate caspase-3 resulting in cells apoptosis,which may contribute to the apoptosis mechanisms.The down-regulated survivin and Bcl-2 may play an important role in A549 cells apoptosis induced by quercetin.