Silencing of CYP6AS160 in Solenopsis invicta Buren by RNA interference enhances worker susceptibility to fipronil.

Cytochrome P450 monooxygenases play a key role in pest resistance to insecticides by detoxification. Four new P450 genes, CYP6AS160, CYP6AS161, CYP4AB73 and CYP4G232 were identified from Solenopsis invicta. CYP6AS160 was highly expressed in the abdomen and its expression could be induced significantly with exposure to fipronil, whereas CYP4AB73 was not highly expressed in the abdomen and its expression could not be significantly induced following exposure to fipronil. Expression levels of CYP6AS160 and CYP4AB73 in workers were significantly higher than that in queens. RNA interference-mediated gene silencing by feeding on double-stranded RNA (dsRNA) found that the levels of this transcript decreased (by maximum to 64.6%) when they fed on CYP6AS160-specific dsRNA. Workers fed dsCYP6AS160 had significantly higher mortality after 24 h of exposure to fipronil compared to controls. Workers fed dsCYP6AS160 had reduced total P450 activity of microsomal preparations toward model substrates p-nitroanisole. However, the knockdown of a non-overexpressed P450 gene, CYP4AB73 did not lead to an increase of mortality or a decrease of total P450 activity. The knockdown effects of CYP6AS160 on worker susceptibility to fipronil, combined with our other findings, indicate that CYP6AS160 is responsible for detoxification of fipronil. Feeding insects dsRNA may be a general strategy to trigger RNA interference and may find applications in entomological research and in the control of insect pests in the field.

CYP4CJ6-mediated resistance to two neonicotinoid insecticides in Sitobion miscanthi (Takahashi).

The wheat aphid Sitobion miscanthi (CWA) is an important harmful pest in wheat fields. Insecticide application is the main method to effectively control wheat aphids. However, CWA has developed resistance to some insecticides due to its extensive application, and understanding resistance mechanisms is crucial for the management of CWA. In our study, a new P450 gene, CYP4CJ6, was identified from CWA and showed a positive response to imidacloprid and thiamethoxam. Transcription of CYP4CJ6 was significantly induced by both imidacloprid and thiamethoxam, and overexpression of CYP4CJ6 in the imidacloprid-resistant strain was also observed. The sensitivity of CWA to these two insecticides was increased after the knockdown of CYP4CJ6. These results indicated that CYP4CJ6 could be associated with CWA resistance to imidacloprid and thiamethoxam. Subsequently, the posttranscriptional regulatory mechanism was assessed, and miR-316 was confirmed to participate in the posttranscriptional regulation of CYP4CJ6. These results are crucial for clarifying the roles of P450 in the resistance of CWA to insecticides.

Identification of differentially expressed microRNAs under imidacloprid exposure in Sitobion miscanthi.

Imidacloprid is a neonicotinoid that targets sucking pests, such as aphids and the green leaf bug and has been widely applied in wheat fields to control wheat aphids in China. To investigate the involvement of miRNAs in imidacloprid resistance, we sequenced small RNA libraries of Sitobion miscanthi Fabricius, across two different treatments using Illumina short-read sequencing technology. As a result, 265 microRNAs (miRNAs), of which 242 were known and 23 were novel, were identified. Quantitative analysis of miRNA levels showed that 23 miRNAs were significantly up-regulated, and 54 miRNAs were significantly down-regulated in the nymphs of S. miscanthi treated with imidacloprid in comparison with those of the control. Modulation of the abundances of differentially expressed miRNAs, smi-miR-316, smi-miR-1000, and smi-miR-iab-4 by the addition of the corresponding antagomir/inhibitor to the artificial diet significantly changed the susceptibility of S. miscanthi to imidacloprid. Subsequently, the post-transcriptional regulatory mechanism was conducted, smi-miR-278 and smi-miR-316 were confirmed to be participated in the post-transcriptional regulation of nAChRα1A and CYP4CJ6, respectively. The results suggested that miRNAs differentially expressed in response to imidacloprid could play a critical regulatory role in the metabolism of S. miscanthi to imidacloprid.

Microarray meta-analysis identifies candidate genes for human spermatogenic arrest.

Male infertility affects approximately half of couples who have difficulty becoming pregnant, and its prevalence is continuously rising. Many studies have been performed using animal testes to reveal the mechanisms of male infertility, but few studies have investigated human testes due to various limitations. The aim of this study was to investigate the gene expression profile of impaired human testes through a meta-analysis of microarray data sets, which was accomplished by using 178 human testis samples and 7 microarray data sets. Impaired testes were categorised into four pathological phenotypes or the normal phenotype based on their Johnsen score. Then, a meta-analysis was performed to screen out the differentially expressed genes (DEGs) in each phenotype. The DEGs were used in a subsequent bioinformatics analysis. Our results identified several novel hub genes and pathways and suggested that G1 mitotic cell cycle arrest was a remarkable feature in pre-meiotic arrest. Furthermore, fifteen p53-interacting proteins, such as ABL1 and HDAC2, whose roles in spermatogenesis have not been well characterised, were selected from the DEGs through a strict screening procedure.

Isolated Enhancement Effect is the Only MRI Finding for Wernicke's encephalopathy.

Wernicke's encephalopathy (WE) is an acute neuropsychiatric disorder that results from thiamine (vitamin B1) deficiency. The typical clinical manifestations, which occur as triads in 20% of patients with the disorder, are acute mental status changes, ophthalmoplegia, and ataxia. Brain magnetic resonance imaging (MRI) has important value in diagnosis as it can reveal abnormalities in the thalamus, mammillary body, third and fourth ventricles, and periaqueductal area. Here we describe a 44-year-old female patient with WE, in the context of fasting following bowel surgery. The unique neuroimaging findings were symmetrical mammillary body and dorsal midbrain abnormalities, only evident on contrast-enhanced brain MRI.

A Case of Cerebral Amyloid Angiopathy-Related Inflammation With the Rare Apolipoprotein ε2/ε2 Genotype.

Cerebral amyloid angiopathy (CAA)-related inflammation (CAA-RI) is a rare CAA variant characterized by acute or subacute encephalopathy, headache, epilepsy, or focal neurological deficits. Radiologically, CAA-RI presents with widespread white matter lesions on brain magnetic resonance imaging (MRI) in addition to the hemorrhagic imaging features of CAA. Previous studies have found that the apolipoprotein E (ApoE) ε4 allele and ε4/ε4 genotype were over-represented in CAA-RI. The role of the ApoE ε2 allele in CAA-RI, however, is largely unknown, partly due to the rarity of the ε2/ε2 genotype in the general population. The authors report the first case of CAA-RI with the rare ApoE ε2/ε2 genotype. The patient presented with mild clinical symptoms but striking neuroimaging abnormalities. The response to small-dose glucocorticoids was satisfactory. Because ApoE ε2 promotes amyloid ß accumulation and fibrinoid necrosis in the cerebral vasculature, the ε2/ε2 genotype, similar to ε4/ε4, may also be a precipitating factor for CAA-RI. To clarify the role of ApoE ε2 in CAA-RI, studies with large sample sizes investigating whether ε2 is more common in patients with CAA-RI than in those with CAA only are warranted.

Differential expression of genes in greenbug (Schizaphis graminum Rondani) treated by imidacloprid and RNA interference.

BACKGROUND: Insecticides act as toxins, inhibitors of digestion and deterrents, and affect the expression of many genes in insects. To assess key genes associated with the detoxification or regulation of imidacloprid in greenbug, Schizaphis graminum (Rondani), the transcriptome and digital gene expression (DGE) profile were analyzed using Illumina sequencing. RESULTS: In total, 48 763 494 clean reads were obtained by sequencing. Expression profile analysis showed that 2782 unigenes were differently expressed between the imidacloprid treatment and control groups. After exposure to imidacloprid, the expression levels of 1846 unigenes were upregulated and 936 were downregulated in comparison with controls. Expression patterns of the top 20 highly expressed genes show that they could be involved in the detoxification of imidacloprid. Silencing of multidrug resistance-associated gene (MRA), GATA-binding gene (GAT) and takeout-like precursor gene (TLP) resulted in increasing susceptibility to imidacloprid. CONCLUSIONS: The differentially expressed genes in S. graminum have potential regulatory or detoxification roles in response to imidacloprid. These results should be useful in understanding the molecular mechanisms of greenbug adaption to imidacloprid. © 2018 Society of Chemical Industry.

Green tea polyphenol epigallocatechin-3-gallate inhibits oxidative damage and preventive effects on carbon tetrachloride-induced hepatic fibrosis.

The aim of the study was to examine the effects of epigallocatechin-3-gallate (EGCG) on hepatic fibrogenesis and on cultured hepatic stellate cells (HSCs). The rat model of carbon tetrachloride (CCl(4))-induced hepatic fibrosis was used to assess the effect of daily intraperitoneal injections of EGCG on the indexes of fibrosis. Histological and hepatic hydroxyproline examination revealed that EGCG significantly arrested progression of hepatic fibrosis. EGCG caused significant amelioration of liver injury (reduced activities of serum alanine aminotransferase and aspartate aminotransferase). The development of CCl(4)-induced hepatic fibrosis altered the redox state with a decreased hepatic glutathione and increased the formation of lipid peroxidative products, which were partially normalized by treatment with EGCG, respectively. Moreover, EGCG markedly attenuated HSC activation as well as matrix metalloproteinase (MMP)-2 activity. In cultured stellate cell, the expression of MMP-2 mRNA and protein were substantially reduced by EGCG treatment. Concanavalin A-induced activation of secreted MMP-2 was inhibited by EGCG through the influence of membrane type 1-MMP activity. These results demonstrate that administration of EGCG may be useful in the treatment and prevention of hepatic fibrosis.

Morin inhibits cell proliferation and fibronectin accumulation in rat glomerular mesangial cells cultured under high glucose condition.

Morin, is a natural bioflavonoid isolated from Chinese herbs of the Moraceae family, has been reported to possess antidiabetic activity. However, the role of morin on glomerular mesangial cells (MCs) proliferation and extracellular matrix (ECM) accumulation in diabetic condition is still unclear. Therefore, in this study, we investigated the role of morin on cell proliferation and ECM accumulation in rat glomerular MCs cultured under high glucose (HG) condition. Our results showed that morin inhibited HG-induced MC proliferation, arrested HG-induced cell-cycle progression, reversed HG-inhibited expression of p21Waf1/Cip1 and p27Kip1. It also inhibited HG-induced ECM expression, ROS generation and NOX4 expression in MCs. Furthermore, morin suppressed HG-induced phosphorylation of p38 MAPK and JNK1/2 in MCs. These data suggest that morin inhibits HG-induced MC proliferation and ECM expression through suppressing the activation of p38 MAPK and JNK signaling pathways. Thus, morin may be useful for the prevention or treatment of diabetic nephropathy.

Clopidogrel resistance response in patients with coronary artery disease and metabolic syndrome: the role of hyperglycemia and obesity.

BACKGROUND: Despite the proven benefits of clopidogrel combined aspirin therapy for coronary artery disease (CAD), CAD patients with metabolic syndrome (MS) still tend to have coronary thrombotic events. We aimed to investigate the influence of metabolic risk factors on the efficacy of clopidogrel treatment in patients with CAD undergoing percutaneous coronary intervention (PCI). METHODS: Cohorts of 168 MS and 168 non-MS subjects with CAD identified by coronary angiography (CAG) were enrolled in our study. MS was defined by modified Adult Treatment Panel III criteria. All subjects had taken 100 mg aspirin and 75 mg clopidogrel daily for more than 1 month, and administered loading doses of 600 mg clopidogrel and 300 mg aspirin before PCI. Blood samples were taken 24 h after the loading doses of clopidogrel and aspirin. Platelet aggregation was measured using light transmittance aggregometry (LTA) and thrombelastography (TEG). Clopidogrel resistance was defined as more than 50% adenosine diphosphate (ADP) induced platelet aggregation as measured by TEG. RESULTS: Platelet aggregation inhibition rate by ADP was significantly lower in patients with MS as measured both by TEG (55% ± 31% vs. 68% ± 32%; P < 0.001) and LTA (29% ± 23% vs. 42% ± 29%; P < 0.001). In the multivariate analysis, elderly [OR (95% CI): 1.483 (1.047-6.248); P = 0.002], obesity [OR (95% CI): 3.608 (1.241-10.488); P = 0.018], high fasting plasma glucose level [OR (95% CI): 2.717 (1.176-6.277); P = 0.019] and hyperuricemia [OR (95% CI): 2.583 (1.095-6.094); P = 0.030] were all statistically risk factors for clopidogrel resistance. CAD patients with diabetes and obesity were more likely to have clopidogrel resistance than the CAD patients without diabetes and obesity [75% (61/81) vs. 43% (67/156); P < 0.001]. CONCLUSIONS: CAD patients with MS appeared to have poorer antiplatelet response to clopidogrel compared to those without MS. Obesity, diabetes and hyperuricemia were all significantly associated with clopidogrel resistance.

MicroRNA-9 reduces cell invasion and E-cadherin secretion in SK-Hep-1 cell.

MicroRNAs (miRNAs) are an abundant class of short noncoding RNAs that can posttranscriptionally regulate gene expression in animals. They are also involved in cancer initiation and progression, and their expression profiles serve as phenotypic signatures of different cancers. The roles played by microRNAs specifically in "micromanagement of metastasis" has been addressed only recently. The molecular mechanisms of hepatocellular carcinoma (HCC) metastasis are still poorly understood. Recent evidence implies genetic determinants of cancer metastasis. Because gene expression signature significantly differs between primary metastasis-free HCC and primary HCC with intrahepatic metastases, miRNA expression in those primary HCC may change correspondingly. The 28 up-regulated miRNAs, part of the reported miRNA profiles of HCC, were compared in primary HCC with or without metastases. Only eight miRNAs were found to be significantly up-regulated in primary HCC with metastases while miR-9 had the highest hold change. miR-9 was highly expressed in SK-Hep-1 cell when compared with other hepatoma cell lines and downregulation of miR-9 reduced SK-Hep-1 cell invasion. E-cadherin, a tumor invasion suppressor in HCC, was found to be a putative gene target of miR-9. E-cadherin was up-regulated by miR-9 inhibitor. The findings suggest miR-9 could be involved in HCC metastasis.

Green tea polyphenol epigallocatechin-3-gallate suppresses rat hepatic stellate cell invasion by inhibition of MMP-2 expression and its activation.

AIM: Epigallocatechin-3-gallate (EGCG) is the major component of green tea polyphenols, whose wide range of biological properties includes anti-fibrogenic activity. Matrix metalloproteinases (MMP) that participate in extracellular matrix degradation are involved in the development of hepatic fibrosis. The present study investigates whether EGCG inhibits activation of the major gelatinase matrix metalloproteinase-2 (MMP-2) in rat hepatic stellate cells (HSC). METHODS: The expression of MMP-2, tissue inhibitors of metalloproteinases-2 (TIMP-2), and membrane-type 1-MMP (MT1-MMP) was assessed by RT-PCR and Western blot analyses. MMP-2 activity was evaluated by zymography and MT1-MMP activity was assessed by an enzymatic assay. HSC migration was measured by a wound healing assay and cell invasion was performed using Transwell cell culture chambers. RESULTS: The expression of MMP-2 mRNA and protein in HSC was substantially reduced by EGCG treatment. EGCG treatment also reduced concanavalin A (ConA)-induced activation of secreted MMP-2 and reduced MT1-MMP activity in a dose-dependent manner. In addition, EGCG inhibited either HSC migration or invasion. CONCLUSION: The abilities of EGCG to suppress MMP-2 activation and HSC invasiveness suggest that EGCG may be useful in the treatment and prevention of hepatic fibrosis.