[Effects of FRNK on activation and migration of hepatic stellate cells]

Objective: To investigate the effect of focal adhesion kinase related non kinase (FRNK) on the activation and migration of hepatic stellate cells (HSCs). Methods: Human liver tissue was divided into healthy control group and fibrosis group from March 2019 to September 2019 in Affiliated Hospital of Guizhou Medical University. C57BL/6 mice were divided into wild type (WT) and FRNK gene knockout type (FRNK^-/-) groups. The liver fibrosis model was established with carbon tetrachloride (CCl₄). After that, FRNK gene overexpression (Ad-FRNK) was constructed with adenovirus vector. HE and Masson staining were used to evaluate the pathological changes and fiber deposition of liver tissue. Western blot was used to detect the expression of PY397-FAK and α-SMA protein. Mouse primary HSCs were extracted, and the effect of FRNK on HSCs migration was detected by wound healing, activation of Rac and Rho was detected by Western blot. Results: The expression of PY397-FAK protein in human liver tissue with hepatic fibrosis was significantly higher than that in healthy control group (0.88±0.09 vs. 0.73±0.09). FRNK was significantly lower than that in control group(0.68±0.09 vs. 0.79±0.11). After animal model was set up, the degree of liver fibrosis in FRNK^-/-mice (153±13)% was more serious than that in WT (100%) group. The expression of PY397-FAK and α-SMA protein was significantly elevated (2.50±0.23 vs. 0.75±0.09, 1.46±0.20 vs. 0.92±0.10). After FRNK gene was re-expressed (100%), the degree of liver fibrosis was mainly reversed [(74±6)%], and the expression of PY397-FAK and α-SMA was accordingly decreased(0.68±0.11 vs. 1.12±0.19,0.68±0.10 vs. 0.85±0.06). In vitro, FRNK inhibited the migration of HSCs [WT∶FRNK^-/-∶Ad-FRNK,(339±49)%∶(580±53)%∶(259±33)%] and the activation of Rac and Rho proteins (Rac: 0.54±0.07 vs. 0.91±0.10 vs. 0.77±0.12,Rho:0.45±0.05 vs. 0.64±0.06 vs. 0.53±0.07), all P<0.01. Conclusions: FRNK can inhibit the activation and migration of HSCs which contributed to liver fibrosis. The potential mechanism is related to down regulation of PY397-FAK and inhibition of Rac and Rho activation.

Cellular mechanism of Tβ4 intervention in liver fibrosis by regulating NF-κB signaling pathway

OBJECTIVE

To investigate the inhibitory effect of thymosin-β4 (Tβ4) on the activation of the human hepatic stellate cell line (HSC-LX2) induced by interleukin (IL)-1β.

MATERIALS AND METHODS

There were 5 groups in this study, i.e., blank control group, negative control group (SI-NC, empty plasmid), model group (20 ng/ml of IL-1β), siRNA-Tβ4 knockdown group (IL-1β and si-Tβ4) and Tβ4 treatment group (IL-1β and 1000 ng/ml of Tβ4). Cell proliferation rate was measured using the Cell Counting Kit-8 (CCK-8) method. The cell cycle change and percentage of apoptotic cells were determined by Propidium Iodide (PI) DNA staining and Annexin V-fluorescein isothiocyanate (FITC) double staining. Cellular nucleic acid levels of p-IKB and nuclear factor-kappa B (NF-κB)/p65 proteins were measured by fluorescent quantitative Real Time-Polymerase Chain Reaction (RT-PCR). Double immunofluorescence staining and Western blot were used to detect nuclear translocation of NF-κB and p65 and levels of cytoplasmic p-IKB protein and nuclear p65 protein.

RESULTS

Due to the G0/G1 phase arrest, the number of cells in the Tβ4 treatment group increased, compared with the model group and the siRNA-Tβ4 knockdown group (p<0.01). In the same between-group comparison, apoptotic rate in the Tβ4 treatment group increased significantly (p<0.05). The cellular nucleic acid levels of p-IKB and NF-κB/p65 were markedly higher in the model group and the siRNA-Tβ4 knockdown group than in the blank control group (p<0.01). The cellular nucleic acid levels of p-IKB and NF-κB/p65 were remarkably lower in the Tβ4 treatment group than in the siRNA-Tβ4 knockdown group (p<0.01). The expression levels of NF-κB/p65 and NF-κB/p50 were significantly lower in the Tβ4 treatment group. The expression levels of cytoplasmic p-IKB and nuclear NF-κB/p65 were lower in the Tβ4 treatment group than in the model group (p<0.01).

CONCLUSIONS

Tβ4 significantly inhibited IL-1β-induced HSC-LX2 cell proliferation. The mechanism may involve decreased activation of the NF-κB pathway, decreased expression of p-IKB and nuclear translocation of p65. Therefore, Tβ4 had the effect of reversing liver fibrosis.

Clinical significance of anti‐glomerular basement membrane antibodies in a cohort of Chinese patients with lupus nephritis

OBJECTIVES

To evaluate the clinical and laboratory features of patients with lupus nephritis (LN) in the presence and absence of anti-glomerular basement membrane antibodies (anti-GBM) and to establish whether the characteristics of the disease correlate with anti-GBM.

METHODS

We performed a retrospective study of 157 hospitalised patients with systemic lupus erythematosus (SLE), 91 of whom had LN. The test for anti-GBM used an enzyme-linked immunosorbent assay (ELISA). Clinical and laboratory data were collected and assessed in LN patients with and without anti-GBM.

RESULTS

Anti-GBM was detected in 14 (8.9%) of 157 patients with SLE. All of the 14 patients developed LN; of these, 10 reached the criteria for crescentic glomerulonephritis (CGN) and five were diagnosed as Goodpasture's disease. Serum anti-GBM levels were correlated with the presence of both anti-double-stranded DNA antibodies (anti-dsDNA) and anti-nucleosome antibodies (anti-NuA). Significant differences in extrarenal clinical manifestations were found between anti-GBM-positive and -negative LN patients, with regard to pleuritis, pulmonary haemorrhage, sinusitis, and anaemia in particular.

CONCLUSIONS

LN with anti-GBM is not rare in Chinese patients. Anti-GBM, together with the additional nephritogenic potential of anti-dsDNA and anti-NuA, may play an essential role in the pathogenesis of the anti-GBM disease in LN. Therefore, in addition to routine anti-GBM assay, anti-dsDNA and anti-NuA measurements should be performed early to ensure a prompt diagnosis and immediate treatment in patients with anti-GBM-mediated disease.