Trimethylamine N-oxide promotes oxidative stress and lipid accumulation in macrophage foam cells via the Nrf2/ABCA1 pathway

Recently, trimethylamine N-oxide (TMAO) has been considered a risk factor for cardiovascular disease and has a proatherogenic effect. Many studies have found that TMAO is involved in plaque oxidative stress and lipid metabolism, but the specific mechanism is still unclear. In our study, meta-analysis and bioinformatic analysis were firstly conducted in the database, and found that the effect of high plasma TMAO levels on promoting atherosclerotic plaque may be related to the expression of key antioxidant genes nuclear factor erytheroid-derived-2-like 2 (NFE2L2/Nrf2) decreased. Next, we assessed the role of Nrf2-mediated signaling pathway in TMAO-treated foam cells. Our results showed that TMAO can inhibit the expression of Nrf2 and its downstream antioxidant response element such as heme oxygenase-1 (HO-1) and glutathione peroxidase4 (GPX4), resulting in increased production of reactive oxygen species and decreased activity of superoxide dismutase, promoting oxidative stress. And TMAO can also promote lipid accumulation in foam cells by inhibiting cholesterol efflux protein expression. In addition, upregulation of Nrf2 expression partially rescues TMAO-induced oxidative stress and reduces ATP-binding cassette A1 (ABCA1)–mediated lipid accumulation. Therefore, TMAO promotes oxidative stress and lipid accumulation in macrophage foam cells through the Nrf2/ABCA1 pathway, which may provide a potential mechanism for the proatherogenic effect of TMAO. (AU)

Trimethylamine N-oxide promotes oxidative stress and lipid accumulation in macrophage foam cells via the Nrf2/ABCA1 pathway

Recently, trimethylamine N-oxide (TMAO) has been considered a risk factor for cardiovascular disease and has a proatherogenic effect. Many studies have found that TMAO is involved in plaque oxidative stress and lipid metabolism, but the specific mechanism is still unclear. In our study, meta-analysis and bioinformatic analysis were firstly conducted in the database, and found that the effect of high plasma TMAO levels on promoting atherosclerotic plaque may be related to the expression of key antioxidant genes nuclear factor erytheroid-derived-2-like 2 (NFE2L2/Nrf2) decreased. Next, we assessed the role of Nrf2-mediated signaling pathway in TMAO-treated foam cells. Our results showed that TMAO can inhibit the expression of Nrf2 and its downstream antioxidant response element such as heme oxygenase-1 (HO-1) and glutathione peroxidase4 (GPX4), resulting in increased production of reactive oxygen species and decreased activity of superoxide dismutase, promoting oxidative stress. And TMAO can also promote lipid accumulation in foam cells by inhibiting cholesterol efflux protein expression. In addition, upregulation of Nrf2 expression partially rescues TMAO-induced oxidative stress and reduces ATP-binding cassette A1 (ABCA1)–mediated lipid accumulation. Therefore, TMAO promotes oxidative stress and lipid accumulation in macrophage foam cells through the Nrf2/ABCA1 pathway, which may provide a potential mechanism for the proatherogenic effect of TMAO. (AU)

Trimethylamine N-oxide promotes oxidative stress and lipid accumulation in macrophage foam cells via the Nrf2/ABCA1 pathway.

Recently, trimethylamine N-oxide (TMAO) has been considered a risk factor for cardiovascular disease and has a proatherogenic effect. Many studies have found that TMAO is involved in plaque oxidative stress and lipid metabolism, but the specific mechanism is still unclear. In our study, meta-analysis and bioinformatic analysis were firstly conducted in the database, and found that the effect of high plasma TMAO levels on promoting atherosclerotic plaque may be related to the expression of key antioxidant genes nuclear factor erytheroid-derived-2-like 2 (NFE2L2/Nrf2) decreased. Next, we assessed the role of Nrf2-mediated signaling pathway in TMAO-treated foam cells. Our results showed that TMAO can inhibit the expression of Nrf2 and its downstream antioxidant response element such as heme oxygenase-1 (HO-1) and glutathione peroxidase4 (GPX4), resulting in increased production of reactive oxygen species and decreased activity of superoxide dismutase, promoting oxidative stress. And TMAO can also promote lipid accumulation in foam cells by inhibiting cholesterol efflux protein expression. In addition, upregulation of Nrf2 expression partially rescues TMAO-induced oxidative stress and reduces ATP-binding cassette A1 (ABCA1)-mediated lipid accumulation. Therefore, TMAO promotes oxidative stress and lipid accumulation in macrophage foam cells through the Nrf2/ABCA1 pathway, which may provide a potential mechanism for the proatherogenic effect of TMAO.

NF-κB/ABCA1 pathway aggravates ox-LDL-induced cell pyroptosis by activation of NLRP3 inflammasomes in THP-1-derived macrophages.

OBJECTIVE: NF-κB (nuclear transcription factor-kappa B) plays a well-known function in the regulation of immune responses and inflammation, but growing evidences support a major role of it in atherosclerosis. Currently, the regulatory mechanism of NF-κB pathway involved in atherosclerosis remains unclear. METHODS: To investigate the role of ox-LDL (oxidized low-density lipoprotein) in NF-κB regulation, the protein expression of phosphorylated NF-κB, a marker of NF-κB pathway activation was measured. The pyroptosis of macrophage was evaluated by western blot and fluorescence microscope. Cholesterol efflux capacity was determined by fluorescence assay and oil red O staining. The inhibitor of activation of NF-κB signal was used to assess the effect of NF-κB signal on macrophage pyroptosis and cholesterol efflux in macrophage. Small interfering RNA of ABCA1 (cholesterol transporters ATP binding boxes A1) was used to assess the effect of ABCA1 on macrophage pyroptosis. RESULTS: In this study, we reported THP-1 derived macrophage can be stimulated to increase pyroptosis by ox-LDL in a concentration-dependent manner. Macrophage pyroptosis was correlated with enhanced activation of NF-κB signal. After using inhibitor of NF-κB phosphorylation to attenuate activation of NF-κB signal, we identified and confirmed the decrease of macrophage pyroptosis and the occurrence of ox-LDL-induced cholesterol efflux disorder. Furthermore, we found that the downregulation of ABCA1 led to increased cell inflammation death. But pyroptosis was blocked, may led to cholesterol efflux dysfunction. CONCLUSION: Taken together, the present results indicate that the mechanism of NF-κB involved in the development of atherosclerosis depends on mediating cell pyroptosis and cholesterol efflux and provide significant light on macrophage NF-κB signal in atherosclerosis.

Study on the Relationship between lncRNA Gene Polymorphism and Systemic Lupus Erythematosus.

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease that can cause damage to multiple systems of the body. A number of studies have shown that long-chain noncoding RNA (lncRNA) can participate in the occurrence and development of a variety of autoimmune diseases. This study is aimed at detecting the expression levels of 5 lncRNAs in SLE patients and healthy controls and at exploring the relationship between expression levels and clinical symptoms and laboratory indicators. Methods: The design type of this study is a case-control study. A total of 76 SLE patients and 71 healthy controls were included in the first phase of the study. Real-time fluorescence quantitative polymerase chain reaction was used to detect the expression level of 5 kinds of lncRNAs including lnc7514, lnc0640, lncagf, nc3643, and lnc5150 in PBMCs of two groups of patients; the expression of lncRNAs in the case group and the control group was analyzed. We analyzed the differences in the expression levels of lncRNAs between case and control groups, and explored the association of expression levels with clinical manifestations and laboratory characteristics. SPSS23.0 was used to analyze the expression level and gene polymorphism results; the statistical analysis test level α = 0.05. Results: The expression level of lnc0640 in PBMCs of SLE patient group was higher than that of healthy control group (Z = -3.56, P = 0.03). However, lnc5150 was lower than in healthy controls (Z = -7.16, P < 0.001). lnc3643 expression levels were lower in SLE patients of SLE patients with pleurisy was lower than that of patients without pleurisy (Z = -2.44, P = 0.02). Low lnc3643 expression levels were observed in PBMCs with SLE patients with rash symptoms (Z = -2.75, P = 0.013). SLE expressed lower lnc3643 levels in PBMCs with SLE compared with those without pleurisy (Z = -2.42, P = 0.02). The above differences were statistically significant. Association analysis of lncRNA expression levels and clinical manifestations in SLE patients found that SLE was lower than those without rash or pleurisy (both P < 0.05); association analysis of lncRNA expression level and laboratory results found a negative correlation between lnc3643, lnc7514, and SLE disease activity score (SLEDAI-2K), blood sink (ESR), and C-reactive protein (CRP) (all P < 0.05). Conclusions: lnc0640 was overexpressed in PBMCs in SLE patients compared with healthy controls. lnc3643 was negatively correlated with SLEDAI, and expression levels were associated with SLE patients with arthritis, rash, and pleuritis.

Effect of autophagy on ferroptosis in foam cells via Nrf2.

The progression of atherosclerotic plaque is accelerated by death of foam cells during the development of the plaque. There are several forms of foam cell death, such as autophagy and ferroptosis forms of cell death together are commonly predominant. Therefore, it is particularly important to study the crosstalk between various forms of cell death in atheroscler and ferroptosis. Although there is a dominant form of cell death that plays a role in the disease, motic plaques. Nuclear factor NF-E2-related factor (Nrf2) has been considered as a major regulator of antioxidant in previous studies, but recent studies have revealed that insufficient cellular autophagy can turn off Nrf2-mediated antioxidant defense while initiating Nrf2-manipulated iron deposition and lipid peroxidation, leading to the development of iron ferroptosis. The present experiment aimed to explain the regulatory mechanism between autophagy and ferroptosis through Nrf2. In this experiment, differentiated human THP-1 macrophages were used, which were treated with ox-LDL into foam cells with the addition of the autophagy inhibitor chloroquine (CQ), the inhibitor of Nrf2 (ML385), the promoter of Nrf2 (t-BHQ), and the inhibitor of ferroptosis (Liproxstatin-1), and the expression levels of autophagy-related proteins p62 and LC3, as well as Nrf2 and ferroptosis-related proteins xCT and GPX4 by WB, foam cell survival by CCK8, and intracellular reactive oxygen levels by Flow cytometry analysis and fluorescence microscopy. The effect of autophagy through Nrf2 on ferroptosis in foam cells was determined. The results revealed that insufficient autophagy in CQ-induced foam cells could lead to foam cell death in atherosclerotic plaques, and the cause of cell death was that insufficient autophagy in foam cells turned off the positive effect of Nfr2 antioxidant, initiated the negative effect of Nrf2 to promote intracellular reactive oxygen species production, and this negative effect promoted ferroptosis in foam cells.

Linc8986 and linc0597 in plasma are novel biomarkers for systemic lupus erythematosus.

Despite increasing evidence that large intergenic non-coding RNAs (lincRNAs) are widely involved in human disease, the role of lincRNAs in the development of systemic lupus erythematosus (SLE) has remained largely elusive. The purpose of the present study was to investigate the expression of three lincRNAs (linc0597, linc8986 and linc7190) in the plasma of patients with SLE and their potential use as biomarkers for the diagnosis and treatment of SLE. Plasma samples were obtained from 54 patients with SLE, 24 patients with rheumatoid arthritis (RA), 24 patients with Sjogren's syndrome (SS) and 22 healthy controls. LincRNA expression levels were measured by reverse transcription-quantitative PCR. Compared with those in the healthy controls, the plasma levels of linc0597 and linc8986 were significantly increased in the patients with SLE (P<0.001), while the difference in the level of linc7190 was not significant (P=0.052). In addition, there was no significant difference in the levels of linc0597 and linc8986 among patients with RA, patients with SS and the healthy controls (P>0.05). Compared with patients with SLE without lupus nephritis (LN), the levels of linc0597 were significantly higher in patients with LN (P=0.044). For linc7190 and linc8986, there was no significant difference between patients with and without LN (P>0.05). Furthermore, complement component 3 (C3) levels were used to evaluate whether the expression of linc8986 and linc0597 is related to the activity of SLE. The results indicated that the levels of linc8986 and linc0597 were negatively correlated with the level of C3 (P<0.001 and P=0.004, respectively). Further analysis suggested that linc0597 and linc8986 were able to specifically identify patients with SLE and that a combination of linc0597 and linc8986 may improve the diagnostic accuracy. Therefore, the plasma levels of linc0597 and linc8986 may be suitable biomarkers for diagnosing SLE.

SIRT1-autophagy axis inhibits excess iron-induced ferroptosis of foam cells and subsequently increases IL-1Β and IL-18.

OBJECTIVE: Ferroptosis is a new form of programmed cell death characterized by an iron-dependent increase in lipid ROS. It has recently been reported that elevated iron levels in macrophages in plaques are associated with atherosclerosis(AS). However, it is not clear whether iron induces ferroptosis and the mechanism of ferroptosis induced by iron in macrophages in plaque. METHODS: THP-1 macrophages were treated with ox-LDL and ferric ammonium citrate(FAC). Activate SIRT1 using SRT1720. Use of RAPA and CQ to promote and suppress autophagy. The expression of SIRT1, GPX4 was detected by Western Blot, and the cell activity and lipid ROS level were also performed. IL-1ß and IL-18 levels were measured using qRT-PCR and ELISA. RESULTS: In this study, we determined that FAC can induce a decrease in foam cell activity rather than macrophage activity, increase lipid ROS levels, decrease GPX4 expression and inhibit SIRT1 expression, and increase IL-1ß and IL-18 levels. SRT1720 activated SIRT1 and reversed the above changes induced by FAC. CQ partially prevents the above changes caused by activating SIRT1. CONCLUSION: Activation of SIRT1 can inhibit the ferroptosis and IL-1ß and IL-18 levels of foam cells in excess iron by autophagy, providing a novel therapeutic target for AS.

A feedback loop: Interactions between Inflammatory Signals and Clonal Hematopoiesis in Cardiovascular Disease.

Age and inflammation are powerful drivers of cardiovascular disease. With the growing recognition that traditional cardiovascular risk factors are not fully accurate predictors of cardiovascular disease, recent studies have revealed the prevalence of positive selection of somatic cell mutations in hematopoietic stem cells in the elderly population, which can cause clonal hematopoiesis. Interestingly, clonal hematopoiesis is not only associated with cancer and death, but also closely related to the risk of increased cardiovascular disease due to mutations in TET2, DNMT3A, ASXL1, and JAK2. However, the mechanism of the interaction of clonal hematopoiesis and cardiovascular disease is only partially understood. In mice, somatic mutations have led to significantly increased expression of inflammatory genes in innate immune cells, which may explain the relationship between mutations and cardiovascular disease. Here, we further discuss the association between inflammatory signaling, clonal hematopoiesis, and cardiovascular disease,and using two hypotheses to propose a feedback loop between inflammatory signaling and clonal hematopoiesis for getting insight into the pathogenesis of cardiovascular diseases in depth. Therapies targeting mutant clones or increased inflammatory mediators may be useful for ameliorating the risk of cardiovascular disease.

Autophagy blockage promotes the pyroptosis of ox-LDL-treated macrophages by modulating the p62/Nrf2/ARE axis.

Atherosclerosis, a chronic comprehensive cardiovascular disease, is characterized by the lipid infiltration, formation of foam cells derived from macrophages and inflammation in the vessel wall. Substantial evidence confirms that the activity of autophagic bodies plays a pivot role in regulating cell deaths, but the mechanisms of autophagy to regulate the pyroptosis of macrophages in atherosclerosis remain unclear. In our study, we explored that ox-LDL decreased the cell viability and destroyed the integrity of cell membrane, resulting in the pyroptosis of THP-1 derived macrophages in a dose-dependent manner. Western blotting, qRT-PCR and ELISA also showed that chloroquine (CQ) could up-regulate the expression of p62 through impairing autophagy and induce the pyroptosis of macrophages treated by ox-LDL, as evidenced by the decrease of cell viability and membrane integrity, and the increase of pro-caspase-1, GSDMD, and proinflammatory factors IL-1ß and IL-18. Further researches demonstrated that Nrf2, a nuclear factor activated by p62, was linked to macrophage pyroptosis. Overactivating or suppressing Nrf2/ARE signaling would correspondingly aggravate or alleviate pyroptosis, in which the level of p62 was regulated by Nrf2 feedback. Then, bioinformatic analysis verified that there was a close interaction between p62, Nrf2/ARE signaling proteins and pyroptosis-related proteins. Taken together, our results show that blocking autophagy promotes the pyroptosis of ox-LDL-treated macrophages via the p62/Nrf2/ARE axis, providing a novel therapeutic target for atherosclerosis.

D-dimer daily continuous tendency predicts the short-term prognosis for COVID-19 independently: A retrospective study from Northeast China.

BACKGROUND AND OBJECTIVE: To study whether D-dimer daily continuous tendency could predict the short-term prognosis of COVID-19. PATIENTS AND METHODES: According to the short-term prognosis, 81 COVID-19 patients were divided into two groups, one of worse prognosis (Group W) and the other of better prognosis (Group B). The slope of D-dimer linear regression during hospitalization (SLOPE) was calculated as an indicator of D-dimer daily continuous tendency. The SLOPE difference between Group W and Group B was compared. The difference between the discharge results and the 3-month follow-up results was also compared. COX regression analysis was used to analyze the relationship between SLOPE and short-term prognosis of COVID-19. RESULTS: There were 16 patients in Group W and 65 patients in Group B. Group W had more critical proportion (p < 0.0001), indicating that the symptoms of its patients were more severe during hospitalization. ARDS, the most visible cause of worse prognosis, accounted for up to 68.75%, and many symptoms merged and resulted in worse prognosis. The D-dimer levels of Group W not only were significantly higher (p < 0.0001), but also showed an increasing trend. In addition, the D-dimer levels at discharge were significantly higher than those at follow-up (p = 0.0261), and the mean difference was as high as 0.7474. SLOPE significantly correlated with the short-term prognosis of COVID-19 independently (RR: 1.687, 95% CI: 1.345-2.116, P < 0.0001). The worst prognosis occurred most likely during the first month after COVID-19 diagnosis. CONCLUSION: Our study found that D-dimer daily continuous tendency independently correlates with worse prognosis and can be used as an independent predictor of the short-term prognosis for COVID-19.

MicroRNA-761 modulates foam cell formation and inflammation through autophagy in the progression of atherosclerosis.

Macrophage-derived foam cells formation is the initial stage of atherosclerosis, and lipid-laden macrophage accumulation is also considered as the symbol of unstable plaque. Autophagy is a subcellular process responsible for the degradation of damaged organelles and aggregated proteins in cells (Grootaert in Oxid Med Cell Longev: 7687083, 2018). Macrophage autophagy plays an important role in atherosclerosis under various stress conditions, and microRNAs are involved in this complicated process. The present study was programmed to explore the effects of microRNA-761 on macrophage-derived foam cell formation, focusing on the role of autophagy in this pathological process. The differentiated human THP-1 macrophages were used in the study. THP-1-derived macrophages were treated with miR-761 mimics or inhibitors and cultured with oxidized low-density lipoprotein to mimic the lipid-rich environment in blood vessel. The expression of miR-761 and mRNA levels of IL-1ß and IL-18 were analyzed by quantitative real-time PCR. The effect of miR-761 on autophagy was evaluated by the protein levels of Beclin1, p62/SQSTM1, microtubule-associated protein light chain 3, mammalian target of rapamycin (mTOR), and unc-51-like autophagy activating kinase 1 (ULK1), determined by immunoblot and autophagic flux detected by fluorescent staining. The secretion of IL-1ß and IL-18 was tested by enzyme-linked immunosorbent reaction kit. Lipid accumulation in foam cells was detected by oil red "O" staining. We demonstrated that miR-761 was able to repress foam cell formation and reduce the production of atherogenic inflammatory cytokines IL-1ß and IL-18 in an autophagy-dependent manner in atherosclerosis, possibly via mTOR-ULK1 signaling pathway. In summary, we described an athero-protective function of miR-761 in macrophages incubated with excess ox-LDL and identified an important novel modulator of mTOR signaling and autophagy in macrophage-derived foam cells. This finding may provide a potential target for the prevention and early treatment in high-risk group of atherosclerosis.

Establishment of Reference Intervals for Blood Cell Analysis of Adult Tibetan Farmers and Herdsmen Over 4100 Meters Above Sea Level in Tibet Based on a Health Survey.

Yang, Wei, Song Zhao, Dan Liu, Guangming Su, Dongwei Zhang, Gui La, Yu Deng, Pian Ni, and Xiuru Guan. Establishment of reference intervals for blood cell analysis of adult Tibetan farmers and herdsmen over 4100 meters above sea level in Tibet based on a health survey. High Alt Med Biol. 21:223-231, 2020. Background: High altitude has substantial influence on reference intervals (RIs) for blood cell analysis. However, the currently used RIs for blood cell analysis in China have not been investigated in people from high-altitude areas, which may potentially cause confusion regarding disease diagnosis and treatment of Tibetan farmers and herdsmen from high-altitude areas. Therefore, it is necessary to establish blood cell analysis RIs that are suitable for people in high-altitude areas. Methods: In total, 1145 healthy Tibetan farmers and herdsmen were recruited who have lived at an altitude from 4100 to 5280 m in Kangma, Tibet, for a long time. The C28-A3 guideline from the Clinical and Laboratory Standards Institute was used to establish the RIs for hemoglobin (HGB) concentrations and red blood cell (RBC), white blood cell (WBC), and platelet (PLT) counts from the blood results of Tibetan participants. Results: There were significant gender differences in blood cell RIs for Tibetan farmers and herdsmen who lived above 4100 m above sea level in Kangma, Tibet. Compared with currently used RIs in China, RIs for HGB concentrations and RBCs in Kangma were significantly higher, whereas WBCs were similar and PLT count was lower. Conclusions: The currently used RIs in China may not be applicable to adult Tibetan farmers and herdsmen above 4100 m in Tibet. The newly obtained RIs can supplement the currently used RIs.

Evaluation of a micro/nanofluidic chip platform for diagnosis of central nervous system infections: a multi-center prospective study.

Central nervous system infection (CNSI) is a significant type of infection that plagues the fields of neurology and neurosurgical science. Prompt and accurate diagnosis of CNSI is a major challenge in clinical and laboratory assessments; however, developing new methods may help improve diagnostic protocols. This study evaluated the second-generation micro/nanofluidic chip platform (MNCP-II), which overcomes the difficulties of diagnosing bacterial and fungal infections in the CNS. The MNCP-II is simple to operate, and can identify 44 genus or species targets and 35 genetic resistance determinants in 50 minutes. To evaluate the diagnostic accuracy of the second-generation micro/nanofluidic chip platform for CNSI in a multicenter study. The limit of detection (LOD) using the second-generation micro/nanofluidic chip platform was first determined using six different microbial standards. A total of 180 bacterium/fungi-containing cerebrospinal fluid (CSF) cultures and 26 CSF samples collected from CNSI patients with negative microbial cultures were evaluated using the MNCP-II platform for the identification of microorganism and determinants of genetic resistance. The results were compared to those obtained with conventional identification and antimicrobial susceptibility testing methods. The LOD of the various microbes tested with the MNCP-II was found to be in the range of 250-500 copies of DNA. For the 180 CSF microbe-positive cultures, the concordance rate between the platform and the conventional identification method was 90.00%; eight species attained 100% consistency. In the detection of 9 kinds of antibiotic resistance genes, including carbapenemases, ESBLs, aminoglycoside, vancomycin-related genes, and mecA, concordance rates with the conventional antimicrobial susceptibility testing methods exceeded 80.00%. For carbapenemases and ESBLs-related genes, both the sensitivity and positive predictive values of the platform tests were high (>90.0%) and could fully meet the requirements of clinical diagnosis. MNCP-II is a very effective molecular detection platform that can assist in the diagnosis of CNSI and can significantly improve diagnostic efficiency.

p62/mTOR/LXRα pathway inhibits cholesterol efflux mediated by ABCA1 and ABCG1 during autophagy blockage.

OBJECTIVE: Atherosclerosis is a disease characterized by abnormal lipid metabolism, and the formation of foam cells is considered an early event of atherosclerosis. Intracellular cholesterol efflux mediated by ABCA1 and ABCG1 helps to reduce lipid accumulation in foam cells. Related studies have shown that autophagy and mTOR are involved in cholesterol efflux, but the role of p62, an autophagy substrate protein, has not been evaluated. METHODS: THP-1 derived macrophages were incubated with ox-LDL to establish a foam cell model and treated with different autophagy inducers. The effects of p62 on cholesterol efflux were investigated using overexpression vectors, gene silencing and western blotting. RESULTS: This study showed a blockage of autophagy and decreased expression of ABCA1 and ABCG1 under the stress of excess ox-LDL in a concentration-dependent manner in THP-1 cells. Furthermore, the activation of autophagy led to increased expression of ABCA1 and ABCG1, as well as their upstream transcription factor LXRα, thereby promoting cholesterol efflux from foam cells. We also demonstrated that accumulated p62 played an important role during autophagy blockage, which was achieved by activating mTOR and then inhibited the expression of LXRα and its downstream target proteins ABCA1 and ABCG1. CONCLUSION: In conclusion, our experiments demonstrated that a p62/mTOR/LXRα signaling pathway was involved in cholesterol efflux mediated by ABCA1 and ABCG1 when autophagy blockage occurred. Our study offers a rationale for the development of autophagy and p62 as a new target for the treatment of atherosclerosis.

High false positive rate of white blood cells in urine samples of pregnant women may be caused by epithelial cells being misclassified by the sysmex UF-1000i urine flow cytometer.

BACKGROUND: The UF-1000i has been widely used in screening urinary sediments. However, the interference factor of the UF-1000i in the screening urinary sediments of pregnant women has not been reported. The aim of the study was to demonstrate that epithelial cells (ECs) cause a high false positive rate of white blood cells (WBCs) by the UF-1000i in pregnant women. METHODS: Urine samples were collected from 207 pregnant women. All samples were measured by the UF-1000i and a microscopic method. RESULTS: The areas under the curve (AUC) for WBC and EC counts were 0.837 (95% CI, 0.773-0.901) and 0.844 (95% CI, 0.785-0.903), respectively. The positive rates of the WBC and EC were 73.43% and 37.20%, respectively, by the UF-1000i, and they were 19.32% and 72.95% by the microscopic method. The positive predictive value, negative predictive value, false positive rates, and false negative rates by the UF-1000i were for WBC 25.66%, 98.18%, 74.34%, and 1.82%, respectively, and for EC they were 96.1%, 40.77%, 3.9%, and 59.23%, respectively. The coefficient of correlation R value was 0.503 (P < 0.01) between WBC by UF-1000i and EC by the microscopic method in WBC false positive samples. CONCLUSIONS: EC could be an interference factor for the UF-1000i in screening urinary WBC of pregnant women, and the high false positive rate for WBC may be caused by ECs being misclassified as WBCs by the UF-1000i. © 2018 The Authors. Cytometry Part B: Clinical Cytometry published by Wiley Periodicals, Inc. on behalf of International Clinical Cytometry Society.

Oxidized low-density lipoprotein-induced p62/SQSTM1 accumulation in THP-1-derived macrophages promotes IL-18 secretion and cell death.

Macrophage autophagy has a protective role in the development of atherosclerosis; however, it turns dysfunctional in advanced lesions with an increase in p62/sequestosome-1 protein. Little is known about the role and significance of p62 accumulation in atherosclerosis. The present study investigated the association between p62 expression and the process of foam cell formation. Foam cell models were established through incubation of THP-1-derived macrophages with oxidized low-density lipoprotein, and the process of foam cell formation was detected by Oil red O staining. Furthermore, the dynamic change of p62 expression was detected by western blotting and quantitative polymerase chain reaction. Additionally, using gene silencing techniques, the roles of p62 in foam cells were investigated with ELISA, MTT and flow cytometry. The results indicated that besides serving as a marker of autophagy deficiency, the p62 protein could also mediate inflammation and cytotoxicity in advanced foam cells. Additionally, the implication of p62 in autophagy inhibition and foam cell formation makes it a key atherogenic factor under autophagy-deficient conditions.

Alterations of the Gut Microbiome in Hypertension.

Introduction: Human gut microbiota is believed to be directly or indirectly involved in cardiovascular diseases and hypertension. However, the identification and functional status of the hypertension-related gut microbe(s) have not yet been surveyed in a comprehensive manner. Methods: Here we characterized the gut microbiome in hypertension status by comparing fecal samples of 60 patients with primary hypertension and 60 gender-, age-, and body weight-matched healthy controls based on whole-metagenome shotgun sequencing. Results: Hypertension implicated a remarkable gut dysbiosis with significant reduction in within-sample diversity and shift in microbial composition. Metagenome-wide association study (MGWAS) revealed 53,953 microbial genes that differ in distribution between the patients and healthy controls (false discovery rate, 0.05) and can be grouped into 68 clusters representing bacterial species. Opportunistic pathogenic taxa, such as, Klebsiella spp., Streptococcus spp., and Parabacteroides merdae were frequently distributed in hypertensive gut microbiome, whereas the short-chain fatty acid producer, such as, Roseburia spp. and Faecalibacterium prausnitzii, were higher in controls. The number of hypertension-associated species also showed stronger correlation to the severity of disease. Functionally, the hypertensive gut microbiome exhibited higher membrane transport, lipopolysaccharide biosynthesis and steroid degradation, while in controls the metabolism of amino acid, cofactors and vitamins was found to be higher. We further provided the microbial markers for disease discrimination and achieved an area under the receiver operator characteristic curve (AUC) of 0.78, demonstrating the potential of gut microbiota in prediction of hypertension. Conclusion: These findings represent specific alterations in microbial diversity, genes, species and functions of the hypertensive gut microbiome. Further studies on the causality relationship between hypertension and gut microbiota will offer new prospects for treating and preventing the hypertension and its associated diseases.

The roles of p62/SQSTM1 on regulation of matrix metalloproteinase-9 gene expression in response to oxLDL in atherosclerosis.

OBJECTIVE: Matrix metalloproteinase-9 (MMP-9) plays an important role in the remodeling of the extracellular matrix in atherosclerosis plaques. Autophagy protects macrophages against the processes of vascular disease. Our research explores how autophagy plays roles in macrophages to secret MMP-9. METHODS AND RESULTS: In response to increased doses of oxLDL or CQ we monitored the autophagic flux. Our results revealed that oxLDL was dynamically associated with autophagy and 100 µg/ml oxLDL blocked autophagic flux in THP-1 cells. Moreover p62/SQSTM1 knocking down and CQ respectively inhibited and increased MMP-9 transcriptional expression. These effects were mediated by inhibition of NF-κB. CONCLUSION: Abundant oxLDL blocked autophagic flux resulting in the aggregation of p62/SQSTM1. Then p62/SQSTM1 was involved in gene expression of MMP-9 via NF-κB-dependent signaling, and thus featuring novel plaque vulnerability properties of the atherosclerotic plaque. Understanding the mechanism that selectively modulates p62/SQSTM1 will provide a novel strategy for anti-atherogenesis.

Trends in HIV infection in the First Affiliated Hospital of Harbin, China.

BACKGROUND: Major hospitals in most Chinese cities have the capability to perform HIV testing. However, it is not a routine test for all patients and, as a result, many patients are not aware of their HIV status. To understand the rate of HIV infection and the factors associated with infection, we tested serum to determine HIV status and analyzed factors associated with HIV infection. METHODS: We collected blood samples from 348,151 patients who visited the First Affiliated Hospital of Harbin Medical University from 1 January 2007 to 31 December 2012. Serum was screened with an ELISA. If the test was positive, we conducted two additional ELISAs: a repeat with the initial kit and one with another kit. If there was a positive result with either of these two ELISA kits, western blotting was performed at Harbin Centers for Disease Control and Prevention. RESULTS: The HIV positivity rate of inpatients significantly increased during the course of this study. HIV infection in patients appeared to differ by sex, age, occupation, marital status, educational level, and route of infection. HIV was more prevalent in men than in women. More than 80% of HIV-positive patients had not received higher (>12 years) education. From 2007 to 2012, HIV-positive patients were mainly infected through sexual transmission. For sexually acquired infections, the rate of HIV infections through homosexual contact has increased rapidly in recent years, and ranged from 36.4% to 65.1%. CONCLUSIONS: The number of patients diagnosed as HIV positive has increased in recent years. Offering routine HIV testing in hospitals is feasible and can increase linkage to HIV care and treatment for many individuals.