👤 Masayoshi Maruyama

APOE polymorphisms are major genetic risk factors of Alzheimer's disease (AD). Compared with APOE3/E3, the APOE4/E4 genotype is associated with a > 14-fold increased risk. Therefore, we hypothesized that conversion of APOE4 to APOE3 would ameliorate AD-related pathologies. Accordingly, we generated a knock-in mouse model harboring an APOE4-FLEx (Flip-Excision) 4-to-3 construct enabling postnatal Cre-mediated APOE4-to-APOE3 switching. This construct comprised an APOE3 exon inserted in a reverse orientation downstream of the APOE4 exon, flanked by alternating loxP and mutant loxP sites, allowing Cre-mediated FLEx switching from APOE4-to-APOE3. For in vitro validation, HEK293T cells were transfected with APOE4-FLEx 4-to-3 plasmid, followed by AAV8-mediated iCre delivery. For in vivo studies, endogenous Apoe was replaced with the APOE4-FLEx 4-to-3 construct to generate APOE4-FLEx 4-to-3 knock-in mice, which were crossed with tamoxifen-inducible Rosa26-CreERT2 mice to yield Cre: APOE4-FLEx 4-to-3 double-knock-in mice. Tamoxifen was administered to induce APOE switching. Cre expression successfully induced APOE4-to-APOE3 switching in vitro. Tamoxifen administration in Cre: APOE4-FLEx 4-to-3 mice triggered APOE4-to-APOE3 switching in the liver, demonstrating the feasibility of postnatal isoform switching. However, brain APOE protein levels were below the detection limit. Investigation of the underlying cause involving transcript analysis revealed aberrant retention of intron 3 (APOE-I3). This abnormal splicing probably contributed to the decreased expression of fully spliced, translation-competent (mature) APOE mRNA, driving the subsequent protein reduction. Although APOE expression across organs in APOE4-FLEx 4-to-3 mice requires further optimization, our findings demonstrate that Cre-mediated FLEx switching can serve as a potential strategy to induce APOE genotype switching in vivo. Show less

Stroke patients are prone to reduced daytime physical activity (PA) and poor nighttime sleep quality. Sleep may influence daytime PA; however, few studies have examined this relationship using objective assessments. This study aimed to investigate the association between PA and sleep among stroke patients in a convalescent rehabilitation ward. This was a cross-sectional study of stroke patients. PA and sleep were measured using a wearable device. PA was categorized into sedentary behavior (SB), light physical activity (LPA), and moderate to vigorous physical activity (MVPA). Sleep was assessed using sleep efficiency (SE), defined as the percentage of time spent asleep while in bed. Associations between SE and each PA parameter were analyzed using correlation and multiple regression analyses. A total of 76 patients (mean age 70.0 ± 12.0 years, 41 males) were analyzed. Median SE was 85.3% (interquartile range [IQR]: 81.2-89.0). The mean duration of daytime PA was 195.2 ± 67.5 min/day for SB, 319.5 ± 46.9 min/day for LPA, and 79.8 (IQR: 50.7-103.1) min/day for MVPA. SE was significantly correlated with MVPA ( In stroke patients undergoing convalescent rehabilitation, SE was associated with SB and MVPA. These findings suggest that improving SE may reduce SB and increasing MVPA during inpatient rehabilitation. Show less

Lactacystin is an irreversible proteasome inhibitor isolated from Streptomyces lactacystinicus. Despite its importance for its biological activity, the biosynthesis of lactacystin remains unknown. In this study, we identified the lactacystin biosynthetic gene cluster by gene disruption and heterologous expression experiments. We also examined the functions of the genes encoding a PKS/NRPS hybrid protein (LctA), NRPS (LctB), ketosynthase-like cyclase (LctC), cytochrome P450 (LctD), MbtH-like protein (LctE), and formyltransferase (LctF) by in vivo and in vitro experiments. In particular, we demonstrated that LctF directly transferred the formyl group of 10-N-formyl tetrahydrofolate to CoA. The formyl group of formyl-CoA was then transferred to ACP1 by LctA_AT1 to form formyl-ACP1. This is the first example of an AT domain recognizing a formyl group. The formyl group is perhaps transferred to methylmalonate tethered on LctA_ACP2 to yield methylmalonyl-semialdehyde-ACP2. Then, it would be condensed with leucine bound to PCP in LctB by the C domain in LctA. Using a mimic compound, we confirmed that LctC catalyzed the formation of the cyclic α,α-disubstituted amino acid structure with concomitant release of the product from PCP. Thus, we figured out the overall biosynthesis of lactacystin including a novel role of a formyl group in a secondary metabolite. Show less

A 64-year-old man was diagnosed with diffuse large B-cell lymphoma (DLBCL). He achieved complete remission after R-CHOP therapy, but experienced relapse as lymphoplasmacytic lymphoma (LPL) 4 years after initial treatment. He was retreated with R-bendamustine therapy, resulting in a second remission. However, he once again experienced relapse as DLBCL 2 years later. Although lymph node lesions disappeared after salvage chemotherapy, facial and hypoglossal nerve paresis due to tumor infiltration appeared. His symptoms were attributed to cranial nerve invasion of transformed LPL, and treatment with tirabrutinib was started. Neurological symptoms markedly improved and high-dose chemotherapy followed by autologous stem cell transplantation was performed, resulting in long-term remission. Mutational analyses suggested that a B cell clone with MYD88 mutation caused the entire course of the disease, and our experience with this case indicates that Bruton's tyrosine kinase (BTK) inhibitor therapy might be effective for such cases. Show less

Resveratrol is a natural phytoalexin that has anti-inflammatory properties, reverses doxorubicin resistance, and inhibits epithelial-mesenchymal transition (EMT) in many types of cancer cells. Fusobacterium nucleatum is reportedly enriched in oral squamous cell carcinoma (OSCC) tissues compared to adjacent normal tissues, sparking interest in the relationship between F. nucleatum and OSCC. Recently, F. nucleatum was shown to be associated with EMT in OSCC. In the present study, we aimed to investigate the effects of the natural plant compound resveratrol on F. nucleatum-induced EMT in OSCC. F. nucleatum was co-cultured with OSCC cells, with a multiplicity of infection (MOI) of 300:1. Resveratrol was used at a concentration of 10 μM. Cell Counting Kit-8 and wound healing assays were performed to examine the viability and migratory ability of OSCC cells. Subsequently, real-time RT-PCR was performed to investigate the gene expression of EMT-related markers. Western blotting and immunofluorescence analyses were used to further analyze the expression of the epithelial marker E-cadherin and the EMT transcription factor SNAI1. Co-cultivation with F. nucleatum did not significantly enhance cell viability. The co-cultured cells displayed similarities to the positive control of EMT, exhibiting enhanced migration and expression changes in EMT-related markers. SNAI1 was significantly upregulated, whereas E-cadherin, was significantly downregulated. Notably, resveratrol inhibited F. nucleatum-induced cell migration, decreasing the expression of SNAI1. Resveratrol inhibited F. nucleatum-induced EMT by downregulating SNAI1, which may provide a target for OSCC treatment. Show less

Renal interstitial fibrosis (RIF) is a common pathological manifestation of chronic kidney diseases. Epithelial-mesenchymal transition (EMT) of tubular epithelial cells is considered a major cause of RIF. Although long non-coding RNAs (lncRNAs) are reportedly involved in various pathophysiological processes, the roles and underlying molecular mechanisms of lncRNAs in the progression of RIF are poorly understood. In this study, we investigated the function of lncRNAs in RIF. Microarray assays showed that expression of the lncRNA lnc-CHAF1B-3 (also called claudin 14 antisense RNA 1) was significantly upregulated in human renal proximal tubular cells by both transforming growth factor-β1 (TGF-β1) and hypoxic stimulation, accompanied with increased expression of EMT-related genes. Knockdown of lnc-CHAF1B-3 significantly suppressed TGF-β1-induced upregulated expression of collagen type I alpha 1, cadherin-2, plasminogen activator inhibitor-1, snail family transcriptional repressor I (SNAI1) and SNAI2. Quantitative reverse transcriptase PCR analyses of paraffin-embedded kidney biopsy samples from IgA nephropathy patients revealed lnc-CHAF1B-3 expression was correlated positively with urinary protein levels and correlated negatively with estimated glomerular filtration rate. Show less

Angiopoietin-like proteins (ANGPTLs) 3, 4, and 8 reportedly contribute to progression of metabolic disease, a risk factor for cardiovascular disease (CVD). The purpose of this study was to investigate whether circulating ANGPTL levels are associated with CVD risk after adjustment for potential confounding factors. We conducted a single center, cross-sectional study of 988 Japanese subjects undergoing routine health checks. Serum ANGPTL3, 4, and 8 levels were measured using an enzyme-linked immunosorbent assay. Using multiple regression analysis we evaluated potential association of circulating ANGPTL3, 4, and 8 levels with general medical status including age, sex, smoking, drinking, obesity, hypertension, impaired glycometabolism, dyslipidemia, hyperuricemia, hepatic impairment, chronic kidney disease, anemia, cardiac abnormality, and inflammation. Circulating ANGPTL3 levels were relatively high in health-related categories of hepatic impairment and inflammation. Circulating ANGPTL4 levels were also significantly high in impaired glycometabolism or hepatic impairment but decreased in inflammation. Finally, increased ANGPTL8 levels were observed in obesity, impaired glycometabolism and dyslipidemia. Particularly, increased levels of circulating ANGPTL8 were positively correlated with circulating triglycerides and LDL-cholesterol levels and inversely correlated with circulating HDL-cholesterol levels. Circulating ANGPTL3, 4, and 8 levels reflect some risk factors for CVD development. Show less

Obesity, a risk factor for all-cause and cardiovascular mortality, is a major health concerns among middle-aged men. The aim of this study was to investigate a possible association of dietary habits and obesity related single nucleotide polymorphisms (SNPs) with obesity and metabolic abnormalities. We conducted a retrospective cohort study using annual health examination data of 5112 male workers, obtained between 2007 and 2011. Average dietary energy was estimated using electronically collected meal purchase data from cafeteria. We examined 8 SNPs related to obesity: GHRL rs696217, PPARG rs1175544, ADIPOQ rs2241766, ADIPOQ rs1501299, PPARD rs2016520, APOA5 rs662799, BRAP rs3782886, and ITGB2 rs235326. We also examined whether SNPs that were shown to associate with obesity affect other metabolic abnormalities such as blood pressure (BP), glucose, and lipid profile. Average dietary energy significantly associated with increased abdominal circumference (AC) and body mass index (BMI). The odds ratios (ORs) of overweight and obesity also increased. The major allele of rs696217 significantly increased BMI and an increased OR with obesity, while the minor allele of rs3782886 was associated with significantly decreased AC and the decreased ORs with overweight and obesity. The minor allele of rs3782886 was also associated with significantly decreased systolic BP (SBP), triglyceride (TG), high-density lipoprotein (HDL), and fasting blood sugar (FBS), while rs696217 was not associated with other metabolic abnormalities. Average dietary energy in lunch, rs3782886, and rs696217 were associated with obesity, and rs3782886 was associated with other metabolic abnormalities. Show less

Several single nucleotide polymorphisms (SNPs) have been implicated in the predisposition to chronic kidney disease (CKD). Atherosclerotic disease is deeply involved in the incidence of CKD; however, whether SNPs related to arteriosclerosis are involved in CKD remains unclear. This study aimed to identify SNPs associated with CKD and to examine whether risk allele accumulation is associated with CKD. We conducted a cross-sectional study using data of 4814 male workers to examine the association between estimated glomerular filtration rate (eGFR) and 59 candidate polymorphisms (17 CKD, 42 atherosclerotic diseases). We defined the genetic risk score (GRS) as the total number of risk alleles that showed a significant association in this analysis and examined the relationship with CKD (eGFR < 60 ml/min/1.73m2). Multivariate logistic regression, discrimination by area under the receiver operating characteristic curve, integrated discrimination improvement (IDI), and category-free net reclassification improvement (cNRI) were evaluated. In total, 432 participants were categorized as having CKD. We found eight candidate SNPs with P value < 0.05 (CX3CR1 rs3732379, SHROOM3 rs17319721, MTP rs1800591, PIP5K1B rs4744712, APOA5 rs662799, BRAP rs3782886, SPATA5L1 rs2467853, and MCP1 rs1024611) in the multivariate linear regression adjusted for age, body mass index, systolic blood pressure, and fasting blood glucose. Among these eight SNPs, BRAP rs3782886 and SPATA5L1 rs2467853 were significantly associated with eGFR (false discovery rate < 0.05). GRS was significantly associated with CKD (odds ratio, 1.17; 95% confidence interval, 1.09-1.26). C-statisics improved from 0.775 to 0.780 but showed no statistical significance. However, adding GRS significantly improved IDI and cNRI (0.0057, P = 0.0028, and 0.212, P < 0.001, respectively). After adjustment for clinical factors, kidney function was associated with BRAP rs3782886 and SPATA5L1 rs2467853 and the GRS for CKD that we developed was associated CKD. Show less

Although many single nucleotide polymorphisms (SNPs) have been identified to be associated with metabolic syndrome (MetS), there was only a slight improvement in the ability to predict future MetS by the simply addition of SNPs to clinical risk markers. To improve the ability to predict future MetS, combinational effects, such as SNP-SNP interaction, SNP-environment interaction, and SNP-clinical parameter (SNP × CP) interaction should be also considered. We performed a case-control study to explore novel SNP × CP interactions as risk markers for MetS based on health check-up data of Japanese male employees. We selected 99 SNPs that were previously reported to be associated with MetS and components of MetS; subsequently, we genotyped these SNPs from 360 cases and 1983 control subjects. First, we performed logistic regression analyses to assess the association of each SNP with MetS. Of these SNPs, five SNPs were significantly associated with MetS (P < 0.05): LRP2 rs2544390, rs1800592 between UCP1 and TBC1D9, APOA5 rs662799, VWF rs7965413, and rs1411766 between MYO16 and IRS2. Furthermore, we performed multiple logistic regression analyses, including an SNP term, a CP term, and an SNP × CP interaction term for each CP and SNP that was significantly associated with MetS. We identified a novel SNP × CP interaction between rs7965413 and platelet count that was significantly associated with MetS [SNP term: odds ratio (OR) = 0.78, P = 0.004; SNP × CP interaction term: OR = 1.33, P = 0.001]. This association of the SNP × CP interaction with MetS remained nominally significant in multiple logistic regression analysis after adjustment for either the number of MetS components or MetS components excluding obesity. Our results reveal new insight into platelet count as a risk marker for MetS. Show less

The ATP-binding cassette transporter A1 (ABCA1) is a membrane transporter that directly contributes to high-density lipoprotein (HDL) biogenesis by regulating the cellular efflux of cholesterol. Since ABCA1 plays a pivotal role in cholesterol homeostasis and HDL metabolism, identification of a novel substance that is capable of increasing its expression would be beneficial for the prevention and therapy of atherosclerosis. In the present study, we studied the effects of ethanolic extracts of Brazilian red propolis (EERP) on ABCA1 expression and cholesterol efflux in THP-1 macrophages. EERP enhanced PPARγ and liver X receptor (LXR) transcriptional activity at 5-15μg/ml, which was associated with upregulation of PPARγ and LXRα expression. It was also found that EERP increase the activity of the ABCA1 promoter, which is positively regulated by LXR. Consistent with these findings, treatment with EERP increased both mRNA and protein expression of ABCA1. Finally, EERP upregulated ApoA-I-mediated cholesterol efflux. Our results showed that EERP promote ApoA-I-mediated cholesterol efflux from macrophages by increasing ABCA1 expression via induction of PPARγ/LXR. Show less

To identify genes with pluripotent state-specific expression in embryonic stem (ES) cells, we compared gene expression profiles between undifferentiated and differentiated mouse ES cells using DNA microarrays. Among the numerous genes identified, we focused on dual specificity phosphatase 6 (DUSP6), which had previously been shown to be expressed in undifferentiated human ES cells. We have identified and characterized a regulatory enhancer that we have termed PEDRE that controls pluripotent state-specific expression of DUSP6. This 82-base pair enhancer overlaps with, but is distinct from, a recently identified regulatory element that is regulated by the FGF-ERK pathway. The sequence of PEDRE is 100% identical between mouse and human DUSP6, suggesting that the molecular basis of DUSP6 gene expression in undifferentiated state of ES cells is highly conserved during evolution. Show less

Activation of the Wnt signaling pathway is frequently observed in hepatocellular carcinoma (HCC), though mutation of three of its components, CTNNB1, AXIN1, and AXIN2, is observed substantially less often. We examined the relationship between Wnt signaling and epigenetic alteration of secreted frizzled-related protein (SFRP) genes in HCC. We frequently detected the active form of beta-catenin and accumulation of nuclear beta-catenin in liver cancer cell lines. We detected methylation of SFRP family genes in liver cancer cell lines (SFRP1, 9/12, 75%; SFRP2, 7/12, 58%; SFRP4, 3/12, 25%; SFRP5, 7/12, 58%) and primary HCCs (SFRP1, 9/19, 47%; SFRP2, 12/19, 63%; SFRP5, 8/19, 42%), though methylation of SFRP4 was not found in primary HCCs. SFRP methylation also was detected in hepatitis B or C virus-associated chronic hepatitis (SFRP1, 6/37, 16%; SFRP2, 14/37, 38%; SFRP5, 5/37, 14%) and liver cirrhosis (SFRP1, 10/28, 36%; SFRP2, 9/28, 32%; SFRP5, 3/28, 11%), suggesting that methylation of these genes is an early event in liver carcinogenesis. Ectopic expression of SFRPs downregulated T-cell factor/lymphocyte enhancer factor (TCF/LEF) transcriptional activity in liver cancer cells, while overexpression of a beta-catenin mutant and depletion of SFRP1 using siRNA synergistically upregulated TCF/LEF transcriptional activity. Our results confirm the frequent methylation and silencing of Wnt antagonist genes in HCC, and suggest that their loss of function contributes to activation of Wnt signaling during hepatocarcinogenesis. Show less