Role of liver X receptors alpha agonist on expressions of LPS-induced inflammatory response associated factor IRAK-4 and NF-kappaB in Kupffer cells

Objective： To explore the role of activated liver X receptor α （LXRα） on the expressions of interleukin-1 receptor associated kinase-4 （IRAK-4） and NF-kappaB （NF-κB） in the inflammatory response which induced by LPS in the Kupffer cells and to investigate the possible mechanisms of LXRα negative regulation of inflammatory response. Methods： The Kupffer cells were isolated from male Kunming mice by collagen perfusion in situ. And these cells were divided into 4 groups： normal control group, LPS treatment group, LXRct agonist T0901317 treatment group, LPS and T0901317 combined treatment group. The LPS treatment group were treated with a final concentration of 1 μg/ml LPS in RPMI 1640 and cultured for 6 h, the T0901317 treatment group were treated with a final concentration of 5 μg/ml in RPMI 1640 and cultured for 24 h, and the combined treatment group received pre-culture for 24 h with a final concentration of 1μg/ml T0901317 in RPMI 1640 and then cultured for 6 h with a final concentration of 5 μg/ml LPS in RPMI 1640. All groups were cultured for 30 h. The expression of LXRα, IRAK-4 and NF-κB at mRNA and protein levels were detected by real-time PCR and Western blotting, and the TNF-α and IL-1β levels were detected by ELISA. Results： The levels of LXRα mRNA and protein were highest in T0901317 group, and lowest in LPS group （P〈0.05）. The level of IRAK4 and NF-κB mRNAs and proteins were evidently lower in the Combined-treated group than in LPS group （P〈0.05）. And the level of TNF-α and IL-1 were observed highest in LPS group （P〈0.05）, but no difference among the Control group, T0901317 group and Combined-treated group （P〉0.05）. Conclusion： These date suggest that the LXR agonists can effectively up-regulate the expressions of LXRα mRNA and protein and inhibit the inflammatory response. This may be via down-regulating the expressions of IRAK4 and NF-κB at mRNA and protein levels.

Different effects of antisense IRAK-2 oligonucleotide on IL-1 and TNF-stimulated NF-kappa B activation

Objective: To investigate the role of interleukin-1 (IL-1) receptor associated kinase-2 (IRAK-2) in IL1 and TNF-stimulated nuclear factor-kappa B (NF-kappa B ) activation. Metbods: The 293 cell was trans fectedwith antisense IRAK-2 oligonucleotide (IRAK-2 ODN) followed by stimulating the cell with IL-1 or tumor necrosis factor (TNF), and then the levels of NF-kappa B activation was analyzed by sandwich enzyme-linked immunosorbent assay (ELISA ). Result: Pre-transfecting with antisense IRAK-2 ODN could remarkably decreasethe levels of NF-kappa B activation stimulated by IL-1 in time- and concentration-dependent manner, it can not attenuate the one stimulated by TNF. Conclusion: The responses of IL-1 and TNF-stimulated NF-kappa B activation to antisense IRAK-2 oligonucleotids were different. IRAK-2 plays a key role in the IL-1 signaling events leading to NF kappa B activation.

Study on effect of imbalance of TRAF-6, IRAK-1 and NALP3 inflammatory factors in patients with gouty arthritis

Objective:To explore the effect of imbalance of tumor necrosis factor receptor related factor-6(TRAF-6),interleukin 1 receptor associated kinase-1(IRAK-1)and neutrophil alkaline phosphatase-3(NALP3)in patients with gouty arthritis.Methods:The retrospective experiment was conducted on 105 patients with gouty arthritis admitted to our hospital(47 patients with acute onset and 58 patients with remission,namely group A and group B);meanwhile,another 61 healthy volunteers were selected for control,namely group C.The enrolling of the three groups was dated from May 2017 to May 2018,and TRAF-6,IRAK-1 and NALP3 of all subjects were tested through real-time fluorescence quantification(RT-PCR),and the correlation between the three inflammatory factors and gouty arthritis was compared.Results:1)Through treatment,ESR,BUA and total addiment in group A and B were higher than those in group C,among which the three indicators in group A were higher than those in group B(P<0.05),while CRP was lower than that of group C,and the two indicators in group A were lower than those in group B(P<0.05).2)There was no significant difference in the relative expression of TRAF-6 mRNA between group A and group B before treatment(P>0.05),significantly lower than group C(P<0.05);the above indicators of group A and group B were improved to some extent after treatment,but group A was still lower than group B(P<0.05),and the degree of improvement of group A was also lower than that of group C(P<0.05),while the degree of improvement of group B was not significantly different from that of group C(P>0.05).3)The relative expression level of IRAK-1mRNA in group A and group B before treatment showed no significant difference(P>0.05),but was also lower than that in group C(P<0.05).The relative expression level of IRAK-1mRNA in group A and group B increased to some extent after treatment,with group A significantly lower than group C(P<0.05),and group B showed no significant difference compared with group C(P>0.05).4)The relative expression level of NALP-3 mRNA in group A and group B showed no significant difference(P>0.05)before treatment,significantly higher than that in group C(P<0.05);the relative expression of NALP-3 mRNA in group A was not significantly decreased(P>0.05)after treatment,while that in group B was significantly decreased after treatment(P<0.05),indicating significant different compared with group A and group C.5)There was no correlation between)TRAF-6,ESR,CRP and total addiment(P>0.05);IRAK-1 was negatively correlated with CRP,BUA and total addiment(P<0.05);NALP-3 was negatively correlated with ESR and CRP(P<0.05).Conclusion:TRAF-6,IRAK-1 and NALP-3 are all under abnormal expression in the developing of new gouty arthritis,acting as important participants in promoting the occurrence,development and outcome of illness states,so the intervening measures should be taken.

Protective Effect of Diallyl Trisulfide on Liver in Rats with Sepsis and the Mechanism

The protective effects of diallyl trisulfide on liver were examined in rats with sepsis. Sepsis was reproduced in rats by cecum ligation and puncture (CLP). Fifty-six male Wistar rats were randomly divided into sham-operated group (group S, n=8), sepsis model group (group C, n=24), diallyl trisulfide (DATS)-treated group (group D, n=24). Animals in groups C and D were further divided into three subgroups according to different observation time points, with 8 rats in each sub-group.Rats in group D and C were intravenously injected with normal saline or DATS respectively at a dose of 20 mg/kg after the establishment of sepsis model. Eight rats in groups C and D were sacrificed at 3, 6 and 24 h post-CLP and their livers were harvested for detection of interleukin (IL)-1 receptor associated kinase-4 (IRAK-4), nuclear factor-κB (NF-κB), c-fos, c-jun, malondialdehydethhe (MDA) and superoxide dismutase (SOD), tumor necrosis factor alpha (TNF-α) and for pathological examination. The results showed that the levels of serum IRAK-4, NF-κB and TNF-α in hepatic tissues were higher in group C than group S (control group) (P<0.05). After DATS treatment, the levels of IRAK-4 and NF-κB in the hepatic tissues and serum TNF-α in group D were lower than those in group C (P<0.05). The levels of c-fos and c-jun and MDA in the hepatic tissues were higher in group C than in group S (P<0.05). After DATS treatment, the levels of c-fos and c-jun and MDA in the hepatic tissues were significantly lower in group D than in group C (P<0.05). When compared with group S group, concentration of SOD in the hepatic tissues in group C was significantly lower (P<0.05). After DATS treatment, the concentration of SOD in the hepatic tissues was higher in group D than in group C (P<0.05). These findings suggested that treatment with DATS could ameliorate sepsis-induced liver injury in rats. The protective effect might be related to its ability to inhibit the signal pathway of IRAK-4 and NF-κB, thereby decreasing the production of oxygen free radicals and down-regulating the expression of c-fos and c-jun.