Mitofusin2 Decreases Intracellular Cholesterol of Oxidized LDL-Induced Foam Cells from Rat Vascular Smooth Muscle Cells

Mitofusin2 （Mfn2） plays a pivotal role in the proliferation and apoptosis of vascular smooth muscle cells （VSMCs）. The purpose of this study was to investigate the effects of Mfn2 on the traffick- ing of intracellular cholesterol in the foam ceils derived from rat VSMCs （rVSMCs） and also to investigate the effects of Mfn2 on the expression of adenosine triphosphate-binding cassette subfamily A member 1 （ABCA1）, adenosine triphosphate-binding cassette subfamily G member 1 （ABCG1） and peroxisome proliferator-activated receptor gamma （PPARy）. The rVSMCs were co-cultured with oxi- dized low density lipoprotein （LDL, 80 ~tg/mL） to produce foam cells and cholesterol accumulation in cells. Before oxidized LDL treatment, different titers （20, 40 and 60 pfu/cell） of recombinant adenovirus containing Mfn2 gene （Adv-Mfn2） were added into the culture medium for 24 h to transfect the Mfn2 gene into the rVSMCs. Then the cells were harvested for analyses. The protein expression of Mfn2 was significantly higher in Adv-Mfn2-transfected group than in untransfected group （P〈0.05）, and the ex- pression levels significantly increased when the titer of Adv-Mfn2 increased （P〈0.05）. At 24 or 48 h af- ter oxidized LDL treatment, rVSMCs became irregular and their nuclei became larger, and their plasma abounded with red lipid droplets. However, the number of red lipid droplets was significantly decreased in Adv-Mfn2-transfected group as compared with untransfected group. At 48 h after oxidized LDL treatment, the intracellular cholesterol in rVSMCs was significantly increased （P〈0.05）, but it was sig- nificantly decreased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）, and it also significantly decreased when the titer of Adv-Mfn2 increased （P〈0.05）. The mRNA and pro- tein expression levels of ABCA1 and ABCG1 were significantly increased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）. Though the mRNA and protein expression levels of PPARy was not significantly increased （P〉0.05）, the phosporylation levels of PPARy were signifi- cantly decreased in Adv-Mfn2-transfected group as compared with untransfected group （P〈0.05）. These results suggest that the transfection of Adv-Mfn2 can significantly reduce intracellular cholesterol in oxidized LDL-induced rVSMCs possibly by decreasing PPAR＇/phosporylation and then increasing pro- tein expression levels of ABCAI and ABCG1, which may be helpful to suppress the formation of foam cells.

Clinical Value of ABCB1 and PAI-1 Gene Polymorphisms in Predicting Glucocorticoid-induced Adverse Reactions in Nephrotic Syndrome Patients

Objective Glucocorticoid(GC)-induced adverse reactions(ARs)have been extensively studied due to their potential impact on patients’health.This study aimed to examine the potential correlation between two polymorphisms[adenosine triphosphate-binding cassette B1(ABCB1)C3435T and plasminogen activator inhibitor-1(PAI-1)4G/5G]and various GC-induced ARs in nephrotic syndrome(NS)patients.Methods In this study,513 NS patients who underwent GC treatment were enrolled.Then,the patients were divided into two groups based on ABCB1 C3435T and PAI-14G/5G genotyping,and intergroup comparisons of clinicopathological data and GC-induced ARs were performed.Univariate and multivariate logistic analyses were subsequently conducted to identify potential risk factors for GC-induced ARs,and a nomogram was subsequently established and validated via the area under the ROC curve(AUC),calibration curve and decision curve analysis(DCA).Results We identified ABCB1 C3435T as an independent risk factor for the development of steroid-associated avascular necrosis of the femoral head(SANFH)(OR:2.191,95%CI:1.258–3.813,P=0.006)but not as a risk factor for the occurrence of steroid diabetes mellitus(S-DM).On the other hand,PAI-14G/5G was identified as an independent risk factor for the development of both SANFH(OR:2.198,95%CI:1.267–3.812,P=0.005)and S-DM(OR:2.080,95%CI:1.166–3.711,P=0.013).Notably,no significant correlation was found between the two gene polymorphisms and other GC-induced ARs.In addition,two nomograms were established and validated to demonstrate strong calibration capability and clinical utility.Conclusion Assessing ABCB1 C3435T and PAI-14G/5G before steroid treatment in NS patients could be useful for identifying patients at a high risk of developing SANFH and S-DM.

Polymorphism analysis of the ABCA3 gene： association with neonatal respiratory distress syndrome in preterm infants

Background Previous reports indicated that mutations in the adenosine triphosphate （ATP）-binding cassette transporter A3 （ABCA3） cause fatal respiratory failure in term infants, and common ABCA3 gene polymorphisms have been characterized at the population level in Caucasians. But the role of ABCA3 in relation to respiratory distress syndrome （RDS） in newborns has not been evaluated within a Chinese population. The aim of this study was to analyze eight single-nucleotide polymorphisms （SNPs） of the ABCA3 gene, and to assess the ABCA3 gene as a candidate gene for susceptibility to RDS in newborns.Methods Eight SNPs were selected and genotyped in 203 newborns. The data analysis and statistical tests were used for allele frequencies, haplotype and Hardy-Weinberg equilibrium pairwise linkage disequilibrium measures. Results There was a haplotype association with SNP rs313909 and SNP rs170447, but no haplotype association was observed among the newborns with and without RDS （P 〉0.05）. The minor allele frequency （G） of the coding SNP （cSNP） rs323043 （P585P） was significantly increased in preterm infants with RDS.Conclusion There is an association between a synonymous cSNP rs323043 and the development of RDS.

An update on placental drug transport and its relevance to fetal drug exposure

Pregnant women are often complicated with diseases that require treatment with medication.Most drugs administered to pregnant women are off-label without the necessary dose,efficacy,and safety information.Knowledge concerning drug transfer across the placental barrier is essential for understanding fetal drug exposure and hence drug safety and efficacy to the fetus.Transporters expressed in the placenta,including adenosine triphosphate(ATP)-binding cassette efflux transporters and solute carrier uptake transporters,play important roles in determining drug transfer across the placental barrier,leading to fetal exposure to the drugs.In this review,we provide an update on placental drug transport,including in vitro cell/tissue,ex vivo human placenta perfusion,and in vivo animal studies that can be used to determine the expression and function of drug transporters in the placenta as well as placental drug transfer and fetal drug exposure.We also describe how the knowledge of placental drug transfer through passive diffusion or active transport can be combined with physiologically based pharmacokinetic modeling and simulation to predict systemic fetal drug exposure.Finally,we highlight knowledge gaps in studying placental drug transport and predicting fetal drug exposure and discuss future research directions to fill these gaps.