[Genetic susceptibility in children with incomplete Kawasaki disease].

OBJECTIVE: To study the frequency distribution of single nucleotide polymorphisms (SNPs) in two genes associated with incomplete Kawasaki disease (KD) (rs1569723 in CD40 gene and rs2736340 in BLK gene), and to investigate its association with the genetic susceptibility and clinical phenotypes of incomplete KD. METHODS: A total of 184 children with incomplete KD and 203 normal children were recruited to carry out a case-control study. The genotypes of SNPs in CD40 gene and BLK gene were determined using polymerase chain reaction-restriction fragment length polymorphism. The frequency distribution of genotypes was compared between the KD and control groups. The association between gene polymorphisms and clinical features of incomplete KD was analyzed. RESULTS: There were no significant differences in genotype (AA, AC, CC) and allele frequencies in CD40 SNP rs1569723 between the KD and control groups. There were significant differences in the frequency distribution of three genotypes (TT, CT, CC) in BLK SNP rs2736340 between the KD and control groups (P=0.031), and the KD group had a significantly higher frequency of T allele than the control group (P=0.007). There were significant differences in the incidence of conjunctival hyperaemia among the patients with different genotypes (rs1569723 in CD40 gene) (P=0.036). The SNP rs2736340 in BLK gene was associated with the extremity changes in KD patients (P=0.017). CONCLUSIONS: The SNP rs2736340 in BLK gene is associated with the susceptibility to incomplete KD, and the SNP rs1569723 in CD40 gene and SNP rs2736340 in BLK gene are associated with some of clinical phenotypes of incomplete KD.

Daidzein suppresses pro-inflammatory chemokine Cxcl2 transcription in TNF-α-stimulated murine lung epithelial cells via depressing PARP-1 activity.

AIM: Daidzein (4',7-dihydroxyisoflavone) is an isoflavone exiting in many herbs that has shown anti-inflammation activity. The aim of this study was to investigate the mechanism underlying its anti-inflammatory action in murine lung epithelial cells. METHODS: C57BL/6 mice were intranasally exposed to TNF-α to induce lung inflammation. The mice were injected with daidzein (400 mg/kg, ip) before TNF-α challenge, and sacrificed 12 h after TNF-α challenge, and lung tissues were collected for analyisis. In in vitro studies, murine MLE-12 epithelial cells were treated with TNF-α (20 ng/mL). The expression of pro-inflammatory chemokine Cxcl2 mRNA and NF-κB transcriptional activity were examined using real-time PCR and a dual reporter assay. Protein poly-adenosine diphosphate-ribosylation (PARylation) was detecyed using Western blotting and immunoprecipitation assays. RESULTS: Pretreatment of the mice with daidzein markedly attenuated TNF-α-induced lung inflammation, and inhibited Cxcl2 expression in lung tissues. Furthermore, daidzein (10 µmol/L) prevented TNF-α-induced increases in Cxcl2 expression and activity and NF-κB transcriptional activity, and markedly inhibited TNF-α-induced protein PARylation in MLE-12 cells in vitro. In MLE-12 cells co-transfected with the PARP-1 expression plasmid and NF-κB-luc (or Cxcl2-luc) reporter plasmid, TNF-α markedly increased NF-κB (or Cxcl2) activation, which were significantly attenuated in the presence of daidzein (or the protein PARylation inhibitor PJ 34). PARP-1 activity assay showed that daidzein (10 µmol/L) reduced the activity of PARP-1 by ∼75%. CONCLUSION: The anti-inflammatory action of daidzein in murine lung epithelial cells seems to be mediated via a direct interaction with PARP-1, which inhibits RelA/p65 protein PARylation required for the transcriptional modulation of pro-inflammatory chemokines such as Cxcl2.

Fluoride-induced oxidative stress of osteoblasts and protective effects of baicalein against fluoride toxicity.

The key role of osteoblasts in skeletal fluorosis makes the exploration of the possible mechanisms of the fluoride-induced oxidative stress of osteoblasts of great importance. In this article, the in vitro effects of fluoride on the oxidative stress of osteoblasts are presented. To study the inhibitory effect of baicalein on the oxidative stress of osteoblasts, the antioxidant activity of baicalein was evaluated for osteoblasts exposed to fluoride. Calvarial osteoblasts were prepared and respectively treated with alpha-MEM (5% calf serum) containing 0.5, 1.0, 2.0, 4.0, 8.0, 12.0, and 20.0 mg/L fluoride for 48 h. Baicalein (10 micromol/L) was added to the cells for the same period of time as that of the fluoride treatment. Low concentrations of fluoride (0.5-2 mg F-/L) stimulated the mitochondrial activity of osteoblasts and produced significant reaction to the oxidative stress, whereas high concentrations of fluoride (>or=12 mg F-/L) inhibited cell proliferation and the activity of antioxidant enzymes. This suggests that the oxidative stress induced by low concentrations of fluoride might mediate or participate in the process of fluoride inducing the proliferation of osteoblasts. The viability of osteoblasts in the high concentrations of fluoride with the addition of 10 mumol/L baicalein (>or=12 mg/L) was higher than those of the same level of fluoride- treated groups without the addition of baicalein. The protective role of baicalein is obvious as an inhibitor of lipid peroxidation against the damage induced by the high concentration of fluoride.

Effect of sodium fluoride on the expression of bcl-2 family and osteopontin in rat renal tubular cells.

Our earlier studies showed that the apoptosis of renal tubules can be induced by sodium fluoride (NaF). The present study was designed to estimated the effects of B-cell lymphoma/leukemia 2 (Bcl-2), Bcl-2-associated protein X (Bax), and osteopontin (OPN) on the apoptosis of renal tubular cells induced by NaF at different levels. The technique of reverse transcription-polymerase chain reaction and densitometer scanning volume density were used to evaluate the changes of Bcl-2, Bax, and OPN mRNA in tubular cells treated with different doses of NaF (0, 1, 5, 7.5, 12.5 mgF-/L) for 48 h. Compared to control, the level of Bax mRNA significantly increased at cells of the 7.5- and 12.5-mg F-/L groups and the expression of Bcl-2 mRNA obviously decreased at cells of the 5- and 7.5-mg F-/L groups. The NaF also enhanced the expression of OPN mRNA in a dose-dependent manner, but the strongest expression of OPN mRNA was observed at cells of the 7.5-mg F-/L group. The results suggested that NaF induces the apoptosis in renal tubules via activation of the Bax expression and Bcl-2 suppression; OPN probably acts as protective role against apoptosis in fluoride-treated renal cells.