[6]-Gingerol enhances the cisplatin sensitivity of gastric cancer cells through inhibition of proliferation and invasion via PI3K/AKT signaling pathway.

Cisplatin-based chemotherapy is a widely used chemotherapeutic regimen for gastric cancer; however, drug resistance limits its efficacy. [6]-Gingerol has been found to exhibit anticancer effects. Here, we aim to explore the potential of [6]-gingerol in combination with cisplatin as a new regimen for gastric cancer. CCK-8 assay and colony formation assay were used to determine the effect of [6]-gingerol in combination with cisplatin on cell viability of gastric cancer cells. Flow cytometry was performed to assess cell cycle distribution. Wound-healing assay and transwell invasion assay were conducted to examine the migration and invasion abilities. Cell cycle and invasion-related proteins and mRNAs, as well as PI3K/AKT signaling proteins, were assessed by western blotting and quantitative real-time polymerase chain reaction. Combination of [6]-gingerol with cisplatin inhibited cell viability and enhanced cell cycle arrest at G1 phase compared with cisplatin alone. The combination treatment inhibited cell migration and invasion ability and decreased cyclin D1, cyclin A2, matrix metalloproteinase-9, p-PI3K, AKT, and p-AKT protein expressions and increased P21 and P27 mRNA levels. Our study demonstrates that [6]-gingerol enhances the cisplatin sensitivity of gastric cancer cells and that the mechanisms involve G1 phase arrest, migration and invasion suppression via PI3K/AKT signaling pathway.

Histone Deacetylase 1 (HDAC1) Negatively Regulates Thermogenic Program in Brown Adipocytes via Coordinated Regulation of Histone H3 Lysine 27 (H3K27) Deacetylation and Methylation.

Inhibiting class I histone deacetylases (HDACs) increases energy expenditure, reduces adiposity, and improves insulin sensitivity in obese mice. However, the precise mechanism is poorly understood. Here, we demonstrate that HDAC1 is a negative regulator of the brown adipocyte thermogenic program. The Hdac1 level is lower in mouse brown fat (BAT) than white fat, is suppressed in mouse BAT during cold exposure or ß3-adrenergic stimulation, and is down-regulated during brown adipocyte differentiation. Remarkably, overexpressing Hdac1 profoundly blocks, whereas deleting Hdac1 significantly enhances, ß-adrenergic activation-induced BAT-specific gene expression in brown adipocytes. ß-Adrenergic activation in brown adipocytes results in a dissociation of HDAC1 from promoters of BAT-specific genes, including uncoupling protein 1 (Ucp1) and peroxisome proliferator-activated receptor γ co-activator 1α (Pgc1α), leading to increased acetylation of histone H3 lysine 27 (H3K27), an epigenetic mark of gene activation. This is followed by dissociation of the polycomb repressive complexes, including the H3K27 methyltransferase enhancer of zeste homologue (EZH2), suppressor of zeste 12 (SUZ12), and ring finger protein 2 (RNF2) from (and concomitant recruitment of H3K27 demethylase ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX) to) Ucp1 and Pgc1α promoters, leading to decreased H3K27 trimethylation, a histone transcriptional repression mark. Thus, HDAC1 negatively regulates the brown adipocyte thermogenic program, and inhibiting Hdac1 promotes BAT-specific gene expression through a coordinated control of increased acetylation and decreased methylation of H3K27, thereby switching the transcriptional repressive state to the active state at the promoters of Ucp1 and Pgc1α. Targeting HDAC1 may be beneficial in prevention and treatment of obesity by enhancing BAT thermogenesis.

[Analysis of parameters of serum concentration and pharmacokinetic of liposome and aqueous solution of toatal ginsenoside of ginseng stems and leaves in rats].

The experiment was aimed to investigate the difference of plasma concentration and pharmacokinetic parameters between liposome and aqueous solution of toatal ginsenoside of ginseng stems and leaves in rats, such as ginsenosides Rg1, Re, Rf, Rb1, Rg2, Rc, Rb2, Rb3, Rd. After intravenous injection of liposome and aqueous solution in rats, the blood was taken from the femoral vein to detect the plasma concentration of the above 9 ginsenoside monomers in different time points by using HPLC. The concentration-time curve was obtained and 3p97 pharmacokinetic software was used to get the pharmacokinetic parameters. After the intravenous injection of ginsenosides to rats, nine ginsenosides were detected in plasma. In general, among these ginsenosides, the peak time of the aqueous solution was between 0.05 to 0.083 3 h, and the serum concentration peak of liposome usually appeared after 0.5 h. After software fitting, the aqueous solution of ginsenoside monomers Rg1, Re, Rf, Rg2, Rc, Rd, Rb3 was two-compartment model, and the liposomes were one-compartment model; aqueous solution and liposome of ginsenoside monomers Rb1 were three-compartment model; aqueous solution of ginsenoside monomers Rb2 was three-compartment model, and its liposome was one-compartment model. Area under the drug time curve (AUC) of these 9 kinds of saponin liposomes was larger than that of aqueous solution, and the retention time of the liposomes was longer than that of the aqueous solution; the removal rate was slower than that of the aqueous solution, and the half-life was longer than that of the water solution. The results from the experiment showed that by intravenous administration, the pharmacokinetic parameters of two formulations were significantly different from each other; the liposomes could not only remain the drug for a longer time in vivo, but also reduce the elimination rate and increase the treatment efficacy. As compared with the traditional dosage forms, the total ginsenoside of ginseng stems and leaves can improve the sustained release of the drug, which is of great significance for the research and development of new dosage forms of ginsenosides in the future.

The Histone Demethylase UTX Promotes Brown Adipocyte Thermogenic Program Via Coordinated Regulation of H3K27 Demethylation and Acetylation.

Brown adipocytes function to dissipate energy as heat through adaptive thermogenesis. Understanding the molecular mechanisms underlying the brown fat thermogenic program may provide insights for the development of therapeutic approaches in the treatment of obesity. Most studies investigating the mechanisms underlying brown fat development focus on genetic mechanisms; little is known about the epigenetic mechanisms in this process. We have discovered that ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX), a histone demethylase for di- or tri-methylated histone 3 lysine 27 (H3K27me2/3), plays a potential role in regulating brown adipocyte thermogenic program. We found that UTX is up-regulated during brown adipocyte differentiation and by cold exposure in both brown adipose tissue (BAT) and white adipose tissue (WAT) of mice, suggesting a potential role in thermogenesis. Inactivation of UTX down-regulates brown fat specific gene expression, while overexpression of UTX does the opposite. Notably, activation of ß adrenergic signaling recruits UTX to the UCP1 and PGC1α promoters, leading to decreased H3K27me3, a histone transcriptional repressive mark. UTX demethylates H3K27me3 and subsequently interacts with the histone acetyltransferase (HAT) protein CBP, resulting in increased H3K27 acetylation (H3K27ac), a histone transcriptional active mark. UTX positively regulate brown adipocyte thermogenic program through coordinated control of demethylating H3K27me3 and acetylating H3K27, switching the transcriptional repressive state to the transcriptional active state at the promoters of UCP1 and PGC1α. We conclude that UTX may play a potential role in regulation of brown adipocyte gene expression and may mediate ß adrenergic activation of brown fat function.

Endothelial cell-derived fibronectin extra domain A promotes colorectal cancer metastasis via inducing epithelial-mesenchymal transition.

Recent evidence has been suggesting the important roles of endothelial cells (ECs) involved in the pathogenesis of several cancers, including colorectal carcinomas (CRCs), but the underlying mechanism remains elusive. We have demonstrated previously that CRC-derived fibronectin extra domain A (EDA) promotes vasculogenesis, tumorigenesis and metastasis of CRCs. At the current study, we showed that EC-secreted EDA promotes the metastatic capacity CRC cells via inducing an epithelial-mesenchymal transition. In vitro and in vivo experiments showed that EC-secreted EDA, via the interaction with integrin α9ß1 on neighboring CRC cells, leads to the activation of focal adhesion kinase as well as Rac signalings, thus strengthens the polarity of cytoskeleton and promotes the invasion capacity of CRC cells. Furthermore, Erk signaling pathway was revealed to critically mediate the effect of EC-derived EDA on CRC cells. Our findings reveal a novel oncogenic role of ECs in promoting CRC malignancy through secreting EDA.

Structural and functional insights into yeast Tbf1 as an atypical telomeric repeat-binding factor.

Telomeric repeat-binding factor 1 (Tbf1) has a similar architecture as the TRF family of telomeric proteins and plays important roles in both telomere homeostasis and ribosome regulation. However, the molecular basis of why Tbf1 has such different functions compared to other TRFs remains unclear. Here, we present the crystal structures of the TRF homology (TRFH) and Myb-L domains from Schizosaccharomyces pombe Tbf1 (spTbf1). TRFH-mediated homodimerization is essential for spTbf1 stability. Importantly, spTbf1TRFH lacks the conserved docking motif for interactions with telomeric proteins, explaining why spTbf1 does not participate in the assembly of the shelterin complex. Finally, structural and biochemical analyses demonstrate that TRFH and Myb-L domains as well as the loop region of spTbf1 coordinate to recognize S. pombe telomeric double-stranded DNA. Overall, our findings provide structural and functional insights into how fungi Tbf1 acts as an atypical telomeric repeat-binding factor, which helps to understand the evolution of TRFH-containing telomeric proteins.

Effect of Home Blood Pressure Telemonitoring Plus Additional Support on Blood Pressure Control: A Randomized Clinical Trial.

Objective: Current clinical evidence on the effects of home blood pressure telemonitoring (HBPT) on improving blood pressure control comes entirely from developed countries. Thus, we performed this randomized controlled trial to evaluate whether HBPT plus support (patient education and clinician remote hypertension management) improves blood pressure control more than usual care (UC) in the Chinese population. Methods: This single-center, randomized controlled study was conducted in Beijing, China. Patients aged 30-75 years were eligible for enrolment if they had blood pressure [systolic (SBP) ≥ 140 mmHg and/or diastolic (DBP) ≥ 90 mmHg; or SBP ≥ 130 mmHg and/or DBP ≥ 80 mmHg with diabetes]. We recruited 190 patients randomized to either the HBPT or the UC groups for 12 weeks. The primary endpoints were blood pressure reduction and the proportion of patients achieving the target blood pressure. Results: Totally, 172 patients completed the study, the HBPT plus support group ( n = 84), and the UC group ( n = 88). Patients in the plus support group showed a greater reduction in mean ambulatory blood pressure than those in the UC group. The plus support group had a significantly higher proportion of patients who achieved the target blood pressure and maintained a dipper blood pressure pattern at the 12th week of follow-up. Additionally, the patients in the plus support group showed lower blood pressure variability and higher drug adherence than those in the UC group. Conclusion: HBPT plus additional support results in greater blood pressure reduction, better blood pressure control, a higher proportion of dipper blood pressure patterns, lower blood pressure variability, and higher drug adherence than UC. The development of telemedicine may be the cornerstone of hypertension management in primary care.

Epigenetic Regulation of Hepatic Lipid Metabolism by DNA Methylation.

While extensive investigations have been devoted to the study of genetic pathways related to fatty liver diseases, much less is known about epigenetic mechanisms underlying these disorders. DNA methylation is an epigenetic link between environmental factors (e.g., diets) and complex diseases (e.g., non-alcoholic fatty liver disease). Here, it is aimed to study the role of DNA methylation in the regulation of hepatic lipid metabolism. A dynamic change in the DNA methylome in the liver of high-fat diet (HFD)-fed mice is discovered, including a marked increase in DNA methylation at the promoter of Beta-klotho (Klb), a co-receptor for the biological functions of fibroblast growth factor (FGF)15/19 and FGF21. DNA methyltransferases (DNMT) 1 and 3A mediate HFD-induced methylation at the Klb promoter. Notably, HFD enhances DNMT1 protein stability via a ubiquitination-mediated mechanism. Liver-specific deletion of Dnmt1 or 3a increases Klb expression and ameliorates HFD-induced hepatic steatosis. Single-nucleus RNA sequencing analysis reveals pathways involved in fatty acid oxidation in Dnmt1-deficient hepatocytes. Targeted demethylation at the Klb promoter increases Klb expression and fatty acid oxidation, resulting in decreased hepatic lipid accumulation. Up-regulation of methyltransferases by HFD may induce hypermethylation of the Klb promoter and subsequent down-regulation of Klb expression, resulting in the development of hepatic steatosis.

Vitamin D Attenuates Airway Inflammation in Asthmatic Guinea Pigs Using Mammalian Target of Rapamycin-Mediated Autophagy.

The purpose of this experiment is to find out the function of Vitamin D (VD) in airway inflammation in asthmatic guinea pigs by regulating mammalian target of rapamycin (mTOR)-mediated autophagy. A total of 40 male guinea pigs were randomly assigned into the Con group, the ovalbumin (OVA)-sensitized group, the VD group, the VD + dimethyl sulfoxide group, and the VD + rapamycin (mTOR inhibitor) group. Then, serum from all groups was harvested for the measurement of immunoglobulin E (IgE), interleukin (IL)-4, and IL-5 levels. Next, bronchoalveolar lavage fluid was collected for cell counting. Moreover, lung tissues were extracted to assess levels of p-mTOR and autophagy factors (LC3B, Beclin1, Atg5, and P62). Compared with the Con group, the OVA group showed elevated levels of IgE, IL-4, and IL-5, increased contents of eosinophils, neutrophil, and lymphocytes, and declined monocytes. And the VD group improved inflammatory reactions in the guinea pigs. Besides, the OVA group showed lower levels of p-mTOR and P62 and higher autophagy levels than the Con group, while the VD group had opposite results. Rapamycin annulled the suppressive role of VD to airway inflammation in asthmatic guinea pigs. VD might inhibit OVA-induced airway inflammation by inducing mTOR activation and downregulating autophagy in asthmatic guinea pigs.

Fully integrated wearable humidity sensor for respiration monitoring.

Respiration monitoring is a promising alternative to medical diagnosis of several diseases. However, current techniques of respiration monitoring often require expensive and cumbersome devices which greatly limit their medical applications. Here, we present a fully integrated wearable device consisting of a flexible LCP-copper interdigital electrode, a sensing layer and a wireless electrochemical analysis system. The developed humidity sensor exhibits a high sensitivity, a good repeatability and a rapid response/recover time. The long-term stability is over 30 days at different relative humidity. By integrating the flexible humidity sensor with miniaturized electrochemical analysis system (0.8 cm × 1.8 cm), response current concerning respiration can be wirelessly transmitted to App-assisted smartphone in real time. Furthermore, the fabricated humidity sensor can realize skin moisture monitoring in a touch-less way. The large-scale production of miniaturized flexible sensor (4 mm × 6 mm) has significantly contributed to commercial deployment.

Vitamin D has an effect on airway inflammation and Th17/Treg balance in asthmatic mice.

Asthma is regarded as a chronic inflammation of the airway. Research has highlighted the significance of Vitamin D in asthma. This study explored the mechanism of vitamin D on asthma. The asthma mouse model was established by ovalbumin (OVA) sensitization and treated with vitamin D (50 or 100 ng/ml). The morphological changes of the airway were observed by HE staining. The serum IgE contents and MDA, ROS, and SOD expressions in the bronchoalveolar lavage fluid (BALF) were detected by ELISA. The Th17 and Treg cells were detected using flow cytometry. The RORγt and Foxp 3 expressions were detected by Reverse transcription quantitative polymerase chain reaction (RT-qPCR). IL-17, IL-10, and TGF-ß1 expressions were detected using ELISA. The NF-κB pathway was blocked using the NF-κB pathway inhibitor, Andrographolide sulfonate. The NF-κB pathway-related indexes were detected by western blotting. After blockade of the NF-κB pathway, the IL-17, IL-10, and TGF-G1 expressions were detected. OVA-sensitized asthma induced airway remodeling and elevated IgE content in mice, which was downregulated after vitamin D treatment. MDA and ROS were upregulated and SOD was downregulated in asthmatic mice, while vitamin D inverted the changes. Th17/Treg ratio was imbalanced, RORγt and IL-17 were upregulated, and Foxp 3, IL-10, and TGF-ß1 were downregulated after OVA sensitization, while vitamin D treatment inverted these changes and inhibited the NF-κB-p65 phosphorylation level. After blockade of the NF-κB pathway, IL-17 was downregulated and IL-10 and TGF-ß1 were upregulated. In conclusion, vitamin D rectified the Th17/Treg balance and alleviated airway inflammation by inhibiting the NF-κB pathway in asthmatic mice.

The histone methyltransferase Suv39h regulates 3T3-L1 adipogenesis.

We discovered a unique expression pattern of two histone methyltransferases Suv39h1 and Suv39h2 during 3T3-L1 adipogenesis, both of which preferentially catalyse the formation of H3K9 dimethylation (H3K9me2) and further H3K9 trimethylation (H3K9me3), a transcriptional repressive mark. The expression of Suv39h1 and Suv39h2 displayed a sharp increase at the early stage of 3T3-L1 differentiation, which peaked after differentiation induction, and then declined towards later stage of differentiation, suggesting a key role for these two histone methyltransferases in adipogenesis. Indeed, inactivating Suv39h1 or Suv39h2 via lentiviral shRNA knockdown inhibited adipogenesis, while overexpressing Suv39h1 promoted adipogenesis. Notably, overexpressing or knocking down Suv39h1 in 3T3-L1 cells was associated with reciprocal changes in the expression of Wnt10a, an anti-adipogenic regulator. Further, Wnt10a knockdown largely prevented the inhibitory effect of Suv39h1 on adipogenesis, indicating Wnt10a as a downstream target mediating Suv39h1's action in adipogenesis. Mechanistically, our comprehensive approaches involving ChIP, co-immunoprecipitation and pyrosequencing analysis demonstrated that Suv39h1 may regulate Wnt10a expression via H3K9 methylation and interaction with DNA methyltransferase 1 (DNMT1) at the Wnt10a promoter, resulting in altered DNA methylation at the promoter. We conclude that Suv39h promotes adipogenesis by epigenetically down-regulating Wnt10a expression via H3K9me3 and DNA methylation at the Wnt10a promoter.Abbreviated title: Suv39h and 3T3-L1 Adipogenesis.

ABHD5 blunts the sensitivity of colorectal cancer to fluorouracil via promoting autophagic uracil yield.

The efficacy of Fluorouracil (FU) in the treatment of colorectal cancer (CRC) is greatly limited by drug resistance. Autophagy has been implicated in chemoresistance, but the role of selective autophagic degradation in regulating chemoresistance remains unknown. In this study, we revealed a critical role of ABHD5 in charging CRC sensitivity to FU via regulating autophagic uracil yield. We demonstrated that ABHD5 localizes to lysosome and interacts with PDIA5 to prevent PDIA5 from interacting with RNASET2 and inactivating RNASET2. ABHD5 deficiency releases PDIA5 to directly interact with RNASET2 and leave RNASET2 in an inactivate state, which impairs RNASET2-mediated autophagic uracil yield and promotes CRC cells to uptake FU as an exogenous uracil, thus increasing their sensitivity to FU. Our findings for the first time reveal a novel role of ABHD5 in regulating lysosome function, highlighting the significance of ABHD5 as a compelling biomarker predicting the sensitivity of CRCs to FU-based chemotherapy.

Prognostic significance of NF-κB expression in non-small cell lung cancer: A meta-analysis.

Nuclear factor kappa B (NF-κB), a key nuclear transcription factor, is associated with prognosis in a variety of human cancers. However, the clinical value of NF-κB in non-small cell lung cancer (NSCLC) is still controversial. Therefore, the aim of this meta-analysis was to obtain an accurate evaluation of the relationship between NF-κB expression and survival prognosis of NSCLC patients based on published articles. PubMed, EMBASE and Web of Science databases were systematically searched for potential articles. A total of 1159 patients from 7 eligible studies comparing prognostic significance of NF-κB expression levels in NSCLC were included in our meta-analysis. I2 statistic and P value were performed to evaluate heterogeneity. The results of analysis were presented as hazard ratio (HR) or odds ratios (OR) with 95% confidence interval (95% CI). Subgroup analysis based on ethnicity of NSCLC patients and NF-kB cellular localization within cancer cells were conducted to illustrate the potential discrepancy. Significant heterogeneity was considered at I2>50% and P<0.05, and random-effects model was used. The combined results indicated that higher NF-κB expression was associated with shorter overall survival (OS) of NSCLC patients (HR = 2.78, 95% CI = 1.51-5.12, P = 0.001). Moreover, NF-κB expression was closely associated with tumor stage (HR = 0.32, 95% CI = 0.18-0.57, P<0.0001), lymph node metastasis (HR = 0.56, 95% CI = 0.38-0.83, P = 0.004) and 5-year OS for NSCLC patients (OR = 1.83, 95% CI = 1.02-3.31, P = 0.04). We conclude that NF-κB expression may be a potential unfavorable prognostic marker for NSCLC patients.

Leucine-nicotinic acid synergy stimulates AMPK/Sirt1 signaling and regulates lipid metabolism and lifespan in Caenorhabditis elegans, and hyperlipidemia and atherosclerosis in mice.

BACKGROUND/AIMS: Nicotinic acid (NA), a lipid-lowering drug, serves as a source of NAD+, the cofactor for Sirt1. Leucine (Leu) stimulates the AMPK/Sirt1 axis and amplifies the effects of other AMPK/Sirt1 activating compounds. Therefore, we tested the interactive effects of leucine and low dose NA on AMPK/Sirt1 signaling and downstream effects of lipid metabolism in cell culture, C. elegans and mice. METHODS: LDL-receptor knockout mice were fed an atherogenic Western diet supplemented with leucine (24 g/kg diet) and sub-therapeutic NA combinations (50 mg/kg diet and 250 mg/kg diet) or low therapeutic NA (1000 mg/kg diet) for 8 weeks to evaluate markers of hyperlipidemia and atherosclerosis. RESULTS: NA-Leu increased P-AMPK and Sirt1 in adipocytes and myotubes. In C. elegans, NA-Leu increased P-AMPK and DAF-16 (FOXO), reduced lipid accumulation and increased median survival under mild oxidative stress conditions. In the mice, NA-Leu reduced total cholesterol, cholesterol esters, plasma triglycerides, atherosclerotic lesion size, lipid area, and aortic macrophage infiltration, similar to the therapeutic NA dose. CONCLUSION: Leu amplifies the effects of NA on lipid metabolism, hyperlipidemia and atherosclerosis in mice, at least in part by activation of the AMPK/Sirt1 axis. This combination may be a potential therapeutic alternative for hyperlipidemia and atherosclerosis.

Erratum: Leucine-nicotinic acid synergy stimulates AMPK/Sirt1 signaling and regulates lipid metabolism and lifespan in Caenorhabditis elegans, and hyperlipidemia and atherosclerosis in mice.

[This corrects the article on p. 33 in vol. 7, PMID: 28533928.].

Epigenetic regulation of E-cadherin expression by the histone demethylase UTX in colon cancer cells.

Decreased epithelial cadherin (E-cadherin) gene expression, a hallmark of epithelial-mesenchymal transition (EMT), is essential for triggering metastatic advantage of the colon cancer. Genetic mechanisms underlying the regulation of E-cadherin expression in EMT have been extensively investigated; however, much is unknown about the epigenetic mechanism underlying this process. Here, we identified ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX), a histone demethylase involved in demethylating di- or tri-methylated histone 3 lysine 27 (H3K27me2/3), as a positive regulator for the expression of E-cadherin in the colon cancer cell line HCT-116. We showed that inactivation of UTX down-regulated E-cadherin gene expression, while overexpression of UTX did the opposite. Notably, overexpression of UTX inhibited migration and invasion of HCT-116 cells. Moreover, UTX demethylated H3K27me3, a histone transcriptional repressive mark, leading to decreased H3K27me3 at the E-cadherin promoter. Further, UTX interacted with the histone acetyltransferase (HAT) protein CBP and recruited it to the E-cadherin promoter, resulting in increased H3K27 acetylation (H3K27ac), a histone transcriptional active mark. UTX positively regulates E-cadherin expression through coordinated regulation of H3K27 demethylation and acetylation, switching the transcriptional repressive state to the transcriptional active state at the E-cadherin promoter. We conclude that UTX may play a role in regulation of E-cadherin gene expression in HCT-116 cells and that UTX may serve as a therapeutic target against the metastasis in the treatment of colon cancer.

Myeloid Deletion of α1AMPK Exacerbates Atherosclerosis in LDL Receptor Knockout (LDLRKO) Mice.

Macrophage inflammation marks all stages of atherogenesis, and AMPK is a regulator of macrophage inflammation. We therefore generated myeloid α1AMPK knockout (MAKO) mice on the LDL receptor knockout (LDLRKO) background to investigate whether myeloid deletion of α1AMPK exacerbates atherosclerosis. When fed an atherogenic diet, MAKO/LDLRKO mice displayed exacerbated atherosclerosis compared with LDLRKO mice. To determine the underlying pathophysiological pathways, we characterized macrophage inflammation/chemotaxis and lipid/cholesterol metabolism in MAKO/LDLRKO mice. Myeloid deletion of α1AMPK increased macrophage inflammatory gene expression and enhanced macrophage migration and adhesion to endothelial cells. Remarkably, MAKO/LDLRKO mice also displayed higher composition of circulating chemotaxically active Ly-6C(high) monocytes, enhanced atherosclerotic plaque chemokine expression, and monocyte recruitment into plaques, leading to increased atherosclerotic plaque macrophage content and inflammation. MAKO/LDLRKO mice also exhibited higher plasma LDL and VLDL cholesterol content, increased circulating apolipoprotein B (apoB) levels, and higher liver apoB expression. We conclude that macrophage α1AMPK deficiency promotes atherogenesis in LDLRKO mice and is associated with enhanced macrophage inflammation and hypercholesterolemia and that macrophage α1AMPK may serve as a therapeutic target for prevention and treatment of atherosclerosis.

Thermoneutrality decreases thermogenic program and promotes adiposity in high-fat diet-fed mice.

Brown/beige adipocytes are therapeutic targets to combat obesity due to their abilities to dissipate energy through adaptive thermogenesis. Most studies investigating induction of brown/beige adipocytes were conducted in cold condition (e.g., 4°C); much is unknown about how the thermogenic program of brown/beige adipocytes is regulated in thermoneutral condition (e.g., 30°C), which is within the thermal comfort zone of human dwellings in daily life. Therefore, this study aims to characterize the thermogenic program of brown/beige adipocytes in mice housed under ambient (22°C) versus thermoneutral condition (30°C). Male mice raised at 22°C or 30°C were fed either chow diet or high-fat (HF) diet for 20 weeks. Despite less food intake, chow-fed mice housed at 30°C remained the same body weight compared to mice at 22°C. However, these thermoneutrally housed mice displayed a decrease in the expression of thermogenic program in both brown and white fat depots with larger adipocytes. When pair-fed with chow diet, thermoneutrally housed mice showed an increase in body weight. Moreover, thermoneutrality increased body weight of mice fed with HF diet. This was associated with decreased expression of the thermogenic program in both brown and white fat depots of the thermoneutrally housed mice. The downregulation of the thermogenic program might have resulted from decreased sympathetic drive in the thermoneutrally housed mice evident by decreased expression of tyrosine hydroxylase expression and norepinephrine turnover in both brown and white fat depots. Our data demonstrate that thermoneutrality may negatively regulate the thermogenic program and sympathetic drive, leading to increased adiposity in mice.

EZH2 promotes colorectal cancer stem-like cell expansion by activating p21cip1-Wnt/ß-catenin signaling.

Because colorectal cancer (CRC) stem-like cells (CCS-like cells) contribute to poor patient prognosis, these cells are a potential target for CRC therapy. However, the mechanism underlying the maintenance of CCS-like cell properties remains unclear. Here, we found that patients with advanced stage CRC expressed high levels of polycomb group protein enhancer of zeste homologue 2 (EZH2). High expression of EZH2 in tumor tissues correlated with poor patient prognosis. Conversely, silencing EZH2 reduced CRC cell proliferation. Surprisingly, EZH2 was more highly expressed in the CCS-like cell subpopulation than in the non-CCS-like cell subpopulation. EZH2 knockdown significantly reduced the CD133+/CD44+ subpopulation, suppressed mammosphere formation, and decreased the expression of self-renewal-related genes and strongly impaired tumor-initiating capacity in a re-implantation mouse model. Gene expression data from 433 human CRC specimens from TCGA database and in vitro results revealed that EZH2 helped maintain CCS-like cell properties by activating the Wnt/ß-catenin pathway. We further revealed that p21cip1-mediated arrest of the cell cycle at G1/S phase is required for EZH2 activation of the Wnt/ß-catenin pathway. Moreover, the specific EZH2 inhibitor EPZ-6438, a clinical trial drug, prevented CRC progression. Collectively, these findings revealed EZH2 maintaining CCS-like cell characteristics by arresting the cell cycle at the G1/S phase. These results indicate a new approach to CRC therapy.