Effect of pirfenidone on renal tubulointerstitial fibrosis

Renal tubulointerstitial fibrosis (TIF) is the common end stage of various chronic renal diseases, and pirfenidone (PFD) is a novel, broad-spectrum anti-fibrotic compound but little is known about its effect and mechanism of action on renal TIF. In this work, we employed a unilateral ureteral obstruction (UUO) rat model to investigate the apoptosis of renal tubular epithelial cells (RTC) after PFD treatment. Thirty-five Sprague Dawley (SD) rats were randomized into three groups: sham-operated group (n=7), UUO group (n=14) and PFD group (n=14). All rats were sacrificed at day 7 or 14 after operation. Renal histology was studied by using periodic acid schiff reagent (PAS) and Masson trichromic stain (MASSON); apoptosis was detected by in situ terminal deoxynucleotide transferase-mediated dUTP-biotin nick end-labeling (TUNEL); tubular caspase-3 expression was assessed by immunohistochemistry. The content of malondialdehyde (MDA) and total activity of superoxide dismutase (T-SOD) in the renal cortex was determined by chemical colorimetry method. TIF, apoptosis of RTC, tubular expression of caspase-3 and the content of MDA were increased in the UUO group compared with those in the sham-operated group, and were ameliorated significantly by PFD treatment (P<0.05). The activity of SOD was decreased in the UUO group, but was improved by PFD treatment (P<0.05). Our results showed that PFD could ameliorate TIF in the UUO group, and the possible mechanism was by reducing the apoptosis of RTC, which involved oxidative stress and caspase-3.     

Correlation between viral load and liver cirrhosis in chronic hepatitis B patients

The aim of this paper is to investigate the relationship between hepatitis B virus (HBV) DNA levels during the course and the progression to cirrhosis with chronic hepatitis B. A total of 239 chronic hepatitis B patients confirmed by liver biopsy between 2001 and 2007 were followed up for a median of 28 months. Compared with the patients without cirrhosis, the patients progressed to cirrhosis were older and with higher HBV-DNA levels at end point. However, there was no significant difference in cirrhosis progression between different HBV-DNA groups at baseline (P = 0.531). Kaplan-Meier analysis showed higher HBV-DNA level at endpoint had increasing risk of cirrhosis (P = 0.019). The results of Cox model indicated that HBV-DNA levels at endpoint, stage of fibrosis, negative hepatitis B e antigen, and γ-glutamyl transpeptidase at baseline were independent risk factors of cirrhosis. The relative risk ratios were 1.898, 1.918, 8.976, and 1.006, respectively. Progression to cirrhosis in chronic hepatitis B patients is correlated with HBV-DNA levels during follow-up.     

Construction of eukaryotic expression vector of human arresten gene and its secreted expression in HEK 293 cells

The eukaryotic expression vector of human arresten gene was constructed and its secretive expression human embryonic kidney (HEK 293) cells was detected. Human arresten gene was amplified from recombinant plasmid pGEM-Arr by polymerase chain reaction (PCR), and then digested with restriction endonucleases BamH I and EcoR I. The target fragment was inserted into the BamH I and EcoR I restriction sites of eukaryotic expression vector pSecTag2 to construct pST-AT. Restriction analysis and DNA sequencing indicated that the arresten gene was successfully inserted into pSecTag2. The recombinant plasmid was subsequently transfected into HEK 293 cells with LipofectAMINETM2000 Reagent, and the expression of the target gene was detected. RT-PCR revealed that the mRNA of the target gene was transcribed in the transfected HEK 293 cells. Western Blot analysis verified that the recombinant protein in supernatants was correct. The supernatants of transfected cells were prepared, and 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay was carried out to assess their effect on the proliferation of human umbilical vein endothelial cells, which showed that the recombinant protein could significantly suppress the proliferation of human umbilical vein endothelial cells in vitro. These results provided a solid foundation to explore the usage of arresten in tumor anti-angiogenic gene therapy.     

Effect of atorvastatin on tumor growth and metastasis in a breast cancer cell xenograft model and its mechanism

This paper aims to evaluate the effects and the possible mechanisms of atorvastatin on tumor growth and metastasis in a xenograft tumor model. Twenty-four female athymic BALB/C mice with MDA-MB-435 xenograft tumors were randomly assigned to three groups: a control group, a low-dose atorvastatin treatment group, and a high-dose atorvastatin treatment group. The mice in the treatment groups began to be administered with atorvastatin (10 or 20 mg/kg per day) when the xenograft tumors reached 1 cm in diameter. At the end of the experiment, the tumor volume and weight and the lung metastasis colonies of each mouse were measured. Western blotting was applied to detect phosphorylation of protein kinase B (PKB, Akt), extracellular signal regulated kinase (ERK), c-Jun N-terminal Kinase (JNK), and the expression of cytochrome P450 (CYP) subtype CYP2J2. Atorvastatin suppressed xenograft tumor growth and metastasis both in the low-dose and the high-dose treatment groups (P < 0.05). Atorvastatin also decreased the phosphorylated Akt (p-Akt) and p-ERK but increased p-JNK expression. However, atorvastatin did not alter the expression of CYP2J2 in tumor tissue. This suggests that atorvastatin has the efficacy of suppressing tumor growth and metastasis in vivo. These effects were not dependent on down-regulation of CYP2J2 expression.