Evaluation of QSAR models for predicting mutagenicity: outcome of the Second Ames/QSAR international challenge project

Quantitative structure-activity relationship (QSAR) models are powerful in silico tools for predicting the mutagenicity of unstable compounds, impurities and metabolites that are difficult to examine using the Ames test. Ideally, Ames/QSAR models for regulatory use should demonstrate high sensitivity, low false-negative rate and wide coverage of chemical space. To promote superior model development, the Division of Genetics and Mutagenesis, National Institute of Health Sciences, Japan (DGM/NIHS), conducted the Second Ames/QSAR International Challenge Project (2020-2022) as a successor to the First Project (2014-2017), with 21 teams from 11 countries participating. The DGM/NIHS provided a curated training dataset of approximately 12,000 chemicals and a trial dataset of approximately 1,600 chemicals, and each participating team predicted the Ames mutagenicity of each trial chemical using various Ames/QSAR models. The DGM/NIHS then provided the Ames test results for trial chemicals to assist in model improvement. Although overall model performance on the Second Project was not superior to that on the First, models from the eight teams participating in both projects achieved higher sensitivity than models from teams participating in only the Second Project. Thus, these evaluations have facilitated the development of QSAR models.

Dual Modification of P3-Type Layered Cathodes to Achieve High Capacity and Long Cyclability for Sodium-Ion Batteries

Sodium-ion batteries (SIBs) have garnered extensive attentions in recent years as a low-cost alternative to lithium-ion batteries. However, achieving both high capacity and long cyclability in cathode materials remains a challenge for SIB commercialization. P3-type Na_0.67Ni_0.33Mn_0.67O₂ cathodes exhibit high capacity and prominent Na⁺ diffusion kinetics but suffer from serious capacity decay and structural deterioration due to stress accumulation and phase transformations upon cycling. In this work, a dual modification strategy with both morphology control and element doping is applied to modify the structure and optimize the properties of the P3-type Na_0.67Ni_0.33Mn_0.67O₂ cathode. The modified Na_0.67Ni_0.26Cu_0.07Mn_0.67O₂ layered cathode with hollow porous microrod structure exhibits an excellent reversible capacity of 167.5 mAh g^-1 at 150 mA g^-1 and maintains a capacity above 95 mAh g^-1 after 300 cycles at 750 mA g^-1. For one thing, the specific morphology shortens the Na⁺ diffusion pathway and releases stress during cycling, leading to excellent rate performance and high cyclability. For another, Cu doping at the Ni site reduces the Na⁺ diffusion energy barrier and mitigates unfavorable phase transitions. This work demonstrates that the electrochemical performance of P3-type cathodes can be significantly improved by applying a dual modification strategy, resulting in reduced stress accumulation and optimized Na⁺ migration behavior for high-performance SIBs.

"Metformin Impairs Intestinal Fructose Metabolism"

Objective

To investigate the effects of metformin on intestinal carbohydrate metabolism in vivo.

Method

Male mice preconditioned with a high-fat, high-sucrose diet were treated orally with metformin or a control solution for two weeks. Fructose metabolism, glucose production from fructose, and production of other fructose-derived metabolites were assessed using stably labeled fructose as a tracer.

Results

Metformin treatment decreased intestinal glucose levels and reduced incorporation of fructose-derived metabolites into glucose. This was associated with decreased intestinal fructose metabolism as indicated by decreased enterocyte F1P levels and diminished labeling of fructose-derived metabolites. Metformin also reduced fructose delivery to the liver. Proteomic analysis revealed that metformin coordinately down-regulated proteins involved carbohydrate metabolism including those involved in fructolysis and glucose production within intestinal tissue.

Conclusion

Metformin reduces intestinal fructose metabolism, and this is associated with broad-based changes in intestinal enzyme and protein levels involved in sugar metabolism indicating that metformin's effects on sugar metabolism are pleiotropic.

Robotic versus laparoscopic left colectomy with complete mesocolic excision for left-sided colon cancer: a multicentre study with propensity score matching analysis

BACKGROUND

Robotic surgery for right-sided colon and rectal cancer has rapidly increased; however, there is limited evidence in the literature of advantages of robotic left colectomy (RLC) for left-sided colon cancer. The purpose of this study was to compare the outcomes of RLC versus laparoscopic left colectomy (LLC) with complete mesocolic excision (CME) for left-sided colon cancer.

METHODS

Patients who had RLC or LLC with CME for left-sided colon cancer at 5 hospitals in China between January 2014 and April 2022 were included. A one-to-one propensity score matched analysis was performed to decrease confounding. The primary outcome was postoperative complications occurring within 30 days of surgery. Secondary outcomes were disease-free survival, overall survival and the number of harvested lymph nodes.

RESULTS

A total of 292 patients (187 males; median age 61.0 [20.0-85.0] years) were eligible for this study, and propensity score matching yielded 102 patients in each group. The clinical-pathological characteristics were well-matched between groups. The two groups did not differ in estimated blood loss, conversion to open rate, time to first flatus, reoperation rate, or postoperative length of hospital stay (p > 0.05). RLC was associated with a longer operation time (192.9 ± 53.2 vs. 168.9 ± 52.8 minutes, p=0.001). The incidence of postoperative complications did not differ between the RLC and LLC groups (18.6% vs. 17.6%, p = 0.856). The total number of lymph nodes harvested in the RLC group was higher than that in the LLC group (15.7 ± 8.3 vs. 12.1 ± 5.9, p< 0.001). There were no significant differences in 3-year and 5-year overall survival or 3-year and 5-year disease-free survival.

CONCLUSIONS

Compared to laparoscopic surgery, RLC with CME for left-sided colon cancer was found to be associated with higher numbers of lymph nodes harvested and similar postoperative complications and long-term survival outcomes.

HGFAC is a ChREBP-regulated hepatokine that enhances glucose and lipid homeostasis

Carbohydrate response element-binding protein (ChREBP) is a carbohydrate-sensing transcription factor that regulates both adaptive and maladaptive genomic responses in coordination of systemic fuel homeostasis. Genetic variants in the ChREBP locus associate with diverse metabolic traits in humans, including circulating lipids. To identify novel ChREBP-regulated hepatokines that contribute to its systemic metabolic effects, we integrated ChREBP ChIP-Seq analysis in mouse liver with human genetic and genomic data for lipid traits and identified hepatocyte growth factor activator (HGFAC) as a promising ChREBP-regulated candidate in mice and humans. HGFAC is a protease that activates the pleiotropic hormone hepatocyte growth factor. We demonstrate that HGFAC-KO mice had phenotypes concordant with putative loss-of-function variants in human HGFAC. Moreover, in gain- and loss-of-function genetic mouse models, we demonstrate that HGFAC enhanced lipid and glucose homeostasis, which may be mediated in part through actions to activate hepatic PPARγ activity. Together, our studies show that ChREBP mediated an adaptive response to overnutrition via activation of HGFAC in the liver to preserve glucose and lipid homeostasis.

The intestine is a major contributor to circulating succinate in mice

The tricarboxylic acid (TCA) cycle is the epicenter of cellular aerobic metabolism. TCA cycle intermediates facilitate energy production and provide anabolic precursors, but also function as intra- and extracellular metabolic signals regulating pleiotropic biological processes. Despite the importance of circulating TCA cycle metabolites as signaling molecules, the source of circulating TCA cycle intermediates remains uncertain. We observe that in mice, the concentration of TCA cycle intermediates in the portal blood exceeds that in tail blood indicating that the gut is a major contributor to circulating TCA cycle metabolites. With a focus on succinate as a representative of a TCA cycle intermediate with signaling activities and using a combination of gut microbiota depletion mouse models and isotopomer tracing, we demonstrate that intestinal microbiota is not a major contributor to circulating succinate. Moreover, we demonstrate that endogenous succinate production is markedly higher than intestinal succinate absorption in normal physiological conditions. Altogether, these results indicate that endogenous succinate production within the intestinal tissue is a major physiological source of circulating succinate. These results provide a foundation for an investigation into the role of the intestine in regulating circulating TCA cycle metabolites and their potential signaling effects on health and disease.

Angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu2(OH)3Br

We report angular dependence of spin-flop transition in triangular lattice antiferromagnet Cu₂(OH)₃Br by angle-dependent magnetization and ESR measurements. The results show that the antiferromagnetic easy magnetization axis is the diagonal direction (θ= 45°) of theac^*plane, i.e., the orientation of Cu1 spins based on the magnetic structure (2020Phys. Rev. Lett.125037204), whereas the spin-flop axis is thebaxis. A phenomenological model is proposed to describe the angle-dependent spin-flop transitions. Based on this model, Cu1 spins are sensitive to external magnetic field, while Cu2 spins are robust against to the field, showing partial decoupling. The model is expected to be used in other uniaxial antiferromagnets with a more general easy axis and complex spin-flop transitions.

Combined transabdominal-transanal surgical approach for iatrogenic rectovaginal fistula: two case reports

Rectovaginal fistula (RVF) is a type of anastomotic leakage that may occur after low anterior resection for rectal cancer. The repair of RVF can be challenging because of the scar tissue stenosis and incomplete obstruction. Two patients presented in our department with vaginal faecal discharge almost 7 months after the radical resection of rectal cancer. On vaginal examination, titanium nails related to the rectal surgery were found in the vaginal wall. The patients were diagnosed with RVF. Considering that RVF positions in the patients were high and might adhere to the pelvic tissue, a combined transabdominal-transanal resection and vaginal repair surgery was performed. About 3 months after surgery, both patients underwent colonic closure surgery, with consequent good recovery. A combined transabdominal-transanal approach may provide distinct advantages in surgical repair of difficult cases of RVF.

A Systems Approach Dissociates Fructose-Induced Liver Triglyceride from Hypertriglyceridemia and Hyperinsulinemia in Male Mice

The metabolic syndrome (MetS), defined as the co-occurrence of disorders including obesity, dyslipidemia, insulin resistance, and hepatic steatosis, has become increasingly prevalent in the world over recent decades. Dietary and other environmental factors interacting with genetic predisposition are likely contributors to this epidemic. Among the involved dietary factors, excessive fructose consumption may be a key contributor. When fructose is consumed in large amounts, it can quickly produce many of the features of MetS both in humans and mice. The mechanisms by which fructose contributes to metabolic disease and its potential interactions with genetic factors in these processes remain uncertain. Here, we generated a small F2 genetic cohort of male mice derived from crossing fructose-sensitive and -resistant mouse strains to investigate the interrelationships between fructose-induced metabolic phenotypes and to identify hepatic transcriptional pathways that associate with these phenotypes. Our analysis indicates that the hepatic transcriptional pathways associated with fructose-induced hypertriglyceridemia and hyperinsulinemia are distinct from those that associate with fructose-mediated changes in body weight and liver triglyceride. These results suggest that multiple independent mechanisms and pathways may contribute to different aspects of fructose-induced metabolic disease.

Combined transabdominal-transanal surgical approach for iatrogenic rectovaginal fistula: two case reports

Rectovaginal fistula (RVF) is a type of anastomotic leakage that may occur after low anterior resection for rectal cancer. The repair of RVF can be challenging because of the scar tissue stenosis and incomplete obstruction. Two patients presented in our department with vaginal faecal discharge almost 7 months after the radical resection of rectal cancer. On vaginal examination, titanium nails related to the rectal surgery were found in the vaginal wall. The patients were diagnosed with RVF. Considering that RVF positions in the patients were high and might adhere to the pelvic tissue, a combined transabdominal-transanal resection and vaginal repair surgery was performed. About 3 months after surgery, both patients underwent colonic closure surgery, with consequent good recovery. A combined transabdominal-transanal approach may provide distinct advantages in surgical repair of difficult cases of RVF.

LncRNA CASC11 promotes the development of lung cancer through targeting microRNA-302/CDK1 axis

OBJECTIVE

To elucidate whether long non-coding RNA cancer susceptibility candidate 11 (lncRNA CASC11) could participate in the development of lung cancer through targeting microRNA-302/CDK1 axis.

PATIENTS AND METHODS

Expression levels of CASC11, microRNA-302 and CDK1 in lung cancer tissues and paracancerous tissues were determined by quantitative real-time polymerase chain reaction (qRT-PCR). CASC11 expression in lung cancer cell lines was also determined. The regulatory effect of CASC11 on proliferative potential of lung cancer cells was accessed by cell counting kit-8 (CCK-8) and colony formation assay. The binding condition between microRNA-302 to CASC11 and CDK1 was evaluated by dual-luciferase reporter gene assay. CDK1 expression in lung cancer cells with CASC11 or microRNA-302 knockdown was detected by Western blot. The proliferation of lung cancer cells was determined after transfection of microRNA-302 inhibitor or co-transfection of microRNA-302 inhibitor and si-CASC11.

RESULTS

CASC11 and CDK1 were highly expressed, whereas microRNA-302 was lowly expressed in lung cancer tissues. Identically, CASC11 was highly expressed in lung cancer cell lines (A547, H157 and SPC-A-1) than controls as well. CASC11 knockdown attenuated proliferative capacity of lung cancer cells. The opposite trend was observed by microRNA-302 knockdown. Dual-luciferase reporter gene assay verified that CASC11 could bind to microRNA-302 and microRNA-302 could bind to CDK1. CDK1 expression in lung cancer cells was negatively regulated by CASC11. MicroRNA-302 knockdown reversed the inhibitory effect of CASC11 on CDK1 expression. The proliferation of lung cancer cells co-transfected with microRNA-302 inhibitor and si-CASC11 decreased compared with those transfected with microRNA-302 inhibitor.

CONCLUSIONS

High expression of CASC11 promotes the development of lung cancer through upregulating CDK1 expression by binding to microRNA-302.

Value of contrast-enhanced ultrasound in the diagnosis of breast US-BI-RADS 3 and 4 lesions with calcifications

AIM

To evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) for Breast Imaging-Reporting and Data System for Ultrasound (US-BI-RADS) 3 and 4 lesions with calcifications.

MATERIALS AND METHODS

A retrospective study of 168 breast lesions with calcifications detected on both mammography and conventional ultrasonography (US) in 152 patients were categorised as US-BI-RADS 3-4 at US between June 2009 and June 2018. CEUS scores were obtained based on a CEUS five-point scoring system. The combination of US-BI-RADS and CEUS scores created the Rerated BI-RADS (referred to as CEUS-BI-RADS). All results were compared with the histological findings. The diagnostic performances of US and CEUS-BI-RADS were compared.

RESULTS

The diagnostic sensitivity, specificity, and accuracy of US were 81.8% (95% confidence interval [CI]: 71.6%, 92%), 85% (95% CI: 78.4%, 91.5%), and 83.9% (95% CI: 78.4%, 89.5%), respectively, while those for CEUS-BI-RADS were 98.2% (95% CI: 94.7%, 100%), 90.3% (95% CI: 84.8%, 95.7%), and 92.9% (95% CI: 89%, 96.8%), respectively. The diagnostic sensitivity and accuracy values of CEUS-BI-RADS greatly improved compared with those of US (p=0.003 and p=0.004, respectively). The areas under the receiver operating characteristic (ROC) curves for US and CEUS-BI-RADS were 0.888 (95% CI: 0.840, 0.936) and 0.963 (95% CI: 0.936, 0.989), respectively. The diagnostic efficacy of CEUS-BI-RADS was significantly higher than that of US alone (p=0.004).

CONCLUSION

CEUS-BI-RADS significantly improves the diagnostic accuracy for breast US-BI-RADS 3 and 4 lesions with calcifications compared with US.

Long noncoding RNA CRNDE promotes proliferation, migration and invasion in prostate cancer through miR-101/Rap1A

Prostate cancer (Pca) is the second frequent malignancy in men. Long noncoding RNAs (lncRNAs) have been reported to play essential roles in the progression of cancers, including Pca. LncRNA colorectal neoplasia differentially expressed (CRNDE) has been found to affect tumorigenesis in many cancers. However, the exact role and mechanism of CRNDE in Pca remain poorly understood. 64 Pca patients were recruited in this study. PC3 and 22RV1 cells were used in vitro experiments. The expressions of CRNDE, microRNA-101 (miR-101), and Ras-related protein 1A (Rap1A) were detected in vivo and in vitro by quantitative real-time polymerase chain reaction and western blot, respectively. Cell proliferation, apoptosis, migration, and invasion were investigated through cell counting kit-8, flow cytometry, and Transwell assays, respectively. The interaction between miR-101 and CRNDE or Rap1A was explored by bioinformatics analysis and luciferase reporter assay. High expression of CRNDE was shown in Pca tissues and cells and predicted poor outcomes of patients. Overexpression of CRNDE promoted cell proliferation, migration, and invasion but decreased apoptosis in Pca cells, while its knockdown showed an opposite effect. CRNDE was a decoy of miR-101 and its effect on Pca progression was reversed by miR-101. Rap1A was identified as a target of miR-101 and it attenuated the effect of miR-101 on Pca development. Moreover, the Rap1A protein level was positively regulated by CRNDE, which was weakened by miR-101. CRNDE contributed to cell proliferation, migration, and invasion by regulating the miR-101/Rap1A axis in Pca, providing a novel strategy for Pca treatment.

Possible magnetic correlation above the ferromagnetic phase transition temperature in Cr2Ge2Te6

Cr₂Ge₂Te₆ has recently emerged as a new two-dimensional ferromagnetic semiconductor (2DFMS) that is promising for spintronic applications. The origin of the ferromagnetism is a debatable point. In this study, ac/dc susceptibility and electronic spin resonance (ESR) measurements are performed to explore the origin of the ferromagnetism in Cr₂Ge₂Te₆. Through the ac susceptibility scaling, the critical temperature T_C = 62.84 K and δ = 5.24 from the critical isotherm, γ + β = 1.78 from the temperature dependence of the crossover line and γ = 1.43 from the temperature dependence of the susceptibility along the same line. Unlike Cr₂Si₂Te₆ whose magnetism can be well described by the 2D-Ising model, Cr₂Ge₂Te₆ cannot be simply described by a single theory model. Meanwhile, the origin of the abnormal critical behavior has been explored and it may be related to the presence of the possible magnetic correlation around the high temperature T* ∼ 160 K, which is confirmed by different probing measurements. The magnetic correlation at high temperature accompanied by the strong magnetic-crystalline anisotropy at low temperature plays an important role in the origin of the abnormal ferromagnetism in Cr₂Ge₂Te₆. Our results may supply a typical reference to investigate the abnormal ferromagnetism of 2DFMSs.

Review article: therapeutic bile acids and the risks for hepatotoxicity

BACKGROUND

Bile acids play important roles in cholesterol metabolism and signal through farnesoid X receptor and G protein-coupled receptors. Given their importance in liver biology, bile acid therapy enables therapeutic applications beyond the treatment of cholestatic liver disease. However, predicting hepatotoxicity of bile acids in humans is obscured due to inconsistent extrapolations of animal data to humans.

AIM

To review the evidence that could explain discordant bile acids hepatotoxicity observed in humans and animals.

METHOD

Literature search was conducted in PubMed using keywords "bile acid," "transporter," "hepatotoxicity," "clinical study," "animal study," "species difference," "mechanism," "genetic disorder." Relevant articles were selected for review.

RESULTS

Clinically significant hepatotoxicity was reported in response to certain bile acids, namely chenodeoxycholic acid, which was given a boxed warning for potential hepatotoxicity. The chemical structure, specifically the number and orientation of hydroxyl groups, significantly affects their hydrophobicity, an important factor in bile acid toxicity. Experimental studies show that hydrophobic bile acids can lead to liver injury through various mechanisms, such as death receptor signalling, mitochondrial dysfunction and inflammation. Although animal studies play a central role in investigating bile acid safety, there are considerable differences in bile acid composition, metabolism and hepatobiliary disposition across species. This does not allow appropriate safety inference, especially for predicting hepatotoxicity in humans. Exploring evidences stemming from inborn errors, genetic models of disease and toxicology studies further improves an understanding of bile acid hepatotoxicity.

CONCLUSION

Species differences should be considered in the development of bile acid related therapeutics. Although the mechanism of bile acid hepatotoxicity is still not fully understood, continued mechanistic studies will deepen our understanding.

Author Correction: Metabolic Biomarkers for Prognostic Prediction of Pre-diabetes: results from a longitudinal cohort study

A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.

Antioxidant MMCC ameliorates catch-up growth related metabolic dysfunction

Postnatal catch-up growth may be related to reduce mitochondrial content and oxidation capacity in skeletal muscle. The aim of this study is to explore the effect and mechanism of antioxidant MitoQuinone mesylate beta cyclodextrin complex (MMCC) ameliorates catch-up growth related metabolic disorders. Catch-up growth mice were created by restricting maternal food intake during the last week of gestation and providing high fat diet after weaning. Low birthweight mice and normal birthweight controls were randomly subjected to normal fat diet, high fat diet and high fat diet with MMCC drinking from the 4th week. MMCC treatment for 21 weeks slowed down the catch up growth and ameliorated catch-up growth related obesity, glucose intolerance and insulin resistance. MMCC administration significantly inhibited the peroxidation of the membrane lipid and up-regulated the antioxidant enzymes Catalase and MnSOD. In addition, MMCC treatment effectively enhanced mitochondrial functions in skeletal muscle through the up-regulation of the ATP generation, and the promotion of mitochondrial replication and remodeling. To conclude, this study demonstrates that antioxidant MMCC effectively ameliorates catch-up growth related metabolic dysfunctions by increasing mitochondrial functions in skeletal muscle.

Metabolic Biomarkers for Prognostic Prediction of Pre-diabetes: results from a longitudinal cohort study

To investigate the metabolic biomarkers of predicting the transition from pre-diabetes (pre-DM) to normal glucose regulation (NGR) and diabetes (DM) in a longitudinal cohort study. 108 participants with pre-DM were followed up for ten years and divided into 3 groups according to different glycemic outcomes. 20 participants progressed to DM, 20 regressed to NGR, and 68 remained at pre-DM. Alterations in plasma metabolites in these groups were evaluated by untargeted ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). Twenty three metabolites related to glycerophospholipid metabolism, oxidation and antioxidation were associated with the process from pre-DM to NGR, while twenty two metabolites related to amino acid metabolism, glycerophospholipid metabolism and mitochondrial β-oxidation played important roles in the progression to DM. Results from stepwise logistic regression analysis showed that five biomarkers (20-Hydroxy-leukotriene E4, Lysopc(20:4), 5-methoxytryptamine, Endomorphin-1, Lysopc(20:3)) were good prediction for the restoration to NGR, and five biomarkers (Iso-valeraldehyde, linoleic acid, Lysopc(18:1), 2-Pyrroloylglycine, Dityrosine) for the development of DM. The findings suggest that the combination of these potential metabolites may be used for the prognosis of pre-DM. Targeting the pathways that involved in these prognostic biomarkers would be beneficial for the regression to NGR and the early prevention of DM among pre-DM.

Deletion of Macrophage Mineralocorticoid Receptor Protects Hepatic Steatosis and Insulin Resistance Through ERα/HGF/Met Pathway

Although the importance of macrophages in nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM) has been recognized, how macrophages affect hepatocytes remains elusive. Mineralocorticoid receptor (MR) has been implicated to play important roles in NAFLD and T2DM. However, cellular and molecular mechanisms are largely unknown. We report that myeloid MR knockout (MRKO) improves glucose intolerance, insulin resistance, and hepatic steatosis in obese mice. Estrogen signaling is sufficient and necessary for such improvements. Hepatic gene and protein expression suggests that MRKO reduces hepatic lipogenesis and lipid storage. In the presence of estrogen, MRKO in macrophages decreases lipid accumulation and increases insulin sensitivity of hepatocytes through hepatocyte growth factor (HGF)/Met signaling. MR directly regulates estrogen receptor 1 (Esr1 [encoding ERα]) in macrophages. Knockdown of hepatic Met eliminates the beneficial effects of MRKO in female obese mice. These findings identify a novel MR/ERα/HGF/Met pathway that conveys metabolic signaling from macrophages to hepatocytes in hepatic steatosis and insulin resistance and provide potential new therapeutic strategies for NAFLD and T2DM.

Downregulation of PCK2 remodels tricarboxylic acid cycle in tumor-repopulating cells of melanoma

For cancer cells to proliferate, a balance must be built between biomass-forming, glucose-metabolized intermediates and ATP production. How intrinsic glucose carbon flow regulates this balance remains unclear. Here we show that mitochondrial phosphoenolpyruvate carboxykinase (PCK2), the hub molecule linking tricarboxylic acid (TCA) cycle, glycolysis and gluconeogenesis by conversion of mitochondrial oxaloacetate (OAA) to phosphoenolpyruvate, regulates glucose carbon flow direction in stem-like cells that repopulate tumors (tumor-repopulating cells (TRCs)). PCK2 downregulation accelerated biosynthesis and transportation of citrate from mitochondria to the cytosol, leading to cytosolic glucose carbon flow via OAA-malate-pyruvate and acetyl-CoA-fatty acid pathways in TRCs. On the other hand, downregulating PCK2 hindered fumarate carbon flows in TCA cycle, leading to attenuated oxidative phosphorylation. In pathological terms, PCK2 overexpression slowed TRC growth in vitro and impeded tumorigenesis in vivo. Overall, our work unveiled unexpected glucose carbon flows of TRCs in melanoma that have implications for targeting metabolic aspects of melanoma.

Liraglutide ameliorates non-alcoholic fatty liver disease by enhancing mitochondrial architecture and promoting autophagy through the SIRT1/SIRT3-FOXO3a pathway

AIM

Overwhelming oxidative stress is implicated as crucial in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Liraglutide, a well-established antidiabetes drug, was recently reported to ameliorate NAFLD with an elusive mechanism. We used a mouse model to examine whether liraglutide could ameliorate NAFLD and explored the possible mechanisms.

METHODS

Twenty C57BL/6J mice were randomly treated with a normal-fat diet or high-fat diet for 16 weeks, then further distributed into four groups and subjected to s.c. injection of liraglutide or saline for 4 weeks. The growth/metabolism, oxidative stress, mitochondrial architecture and autophagy were assessed prospectively at the 20th week.

RESULTS

High-fat diet inducement resulted in severe NAFLD while liraglutide treatment significantly reversed the trend, marked by reduced bodyweight, improved glucose tolerance and liver triglyceride composition. Reduced hepatic malondialdehyde level, increased mRNA and protein levels of CATALASE and MNSOD indicated liraglutide affected both the oxidative and antioxidative process to ameliorate oxidative stress. After liraglutide administration, the upregulated mRNA and protein levels of mitochondrial fission and fusion-related DRP1, OPA1 and respiratory chain-related COMPLEX1, UCP2 demonstrated the enhancement of mitochondrial architecture which may attenuate the generation of reactive oxygen species (ROS), while the diminished mRNA and protein level of P62 and increased levels of Beclin1 and LC3II/I ratio indicated the promoting autophagy, which probably contribute to the ROS elimination. Further, restored protein levels of Sirtuin1/Sirtuin3 and the downstream p-FOXO3a reveal the probable pathways of liraglutide acting on autophagy.

CONCLUSION

Liraglutide diminishes oxidative stress by enhancing mitochondrial architecture and promoting autophagy through the SIRT1/SIRT3-FOXO3a-LC3 pathway to ameliorate diet-induced NAFLD.

Endurance exercise ameliorates low birthweight developed catch-up growth related metabolic dysfunctions in a mouse model

Low birthweight is known to predict high risk of metabolic diseases in adulthood, while regular endurance exercises are believed sufficient to improve metabolic dysfunction. In this study, we established a mouse model to determine whether long-term exercise training could ameliorate catch-up growth, and we explored the possible underlying mechanisms. By restricting maternal food intake during the last week of gestation, we successfully produced low birthweight pups. Further, normal birthweight mice and low birthweight mice were randomly distributed into one of three groups receiving either a normal fat diet, high fat diet, or high fat diet with exercise training. The growth/metabolism, mitochondrial content and functions were assessed at 6 months of age. Through group comparisons and correlation analyses, the 4th week was demonstrated to be the period of crucial growth and chosen to be the precise point of intervention, as the growth rate at this point is significantly correlated with body weight, intraperitoneal glucose tolerance test (IPGTT), Lee's index and fat mass in adulthood. In addition, regular endurance exercises when started from 4 weeks remarkably ameliorated low birthweight outcomes and induced catch-up growth and glucose intolerance in the 25th week. Furthermore, real-time PCR and western blot results indicated that the effect of long-term exercise on mitochondrial functions alleviated catch-up related metabolic dysfunction. To conclude, long-term exercise training from the 4th week is sufficient to ameliorate catch-up growth and related metabolic disturbances in adulthood by promoting mitochondrial functions in skeletal muscle.

Gender-related affecting factors of prediabetes on its 10-year outcome

OBJECTIVE

To investigate the gender-related affecting factors of prediabetes on its 10-year outcome, in a longitudinal study.

METHODS AND RESULTS

This longitudinal population-based study was performed in the Ping Liang community, Yangpu district, Shanghai, between November 2002 and October 2014. There were 334 participants with prediabetes enrolled in the final analysis. While a certain proportion of the prediabetic population progress to diabetes, the majority remain at the same level or even revert to normal glucose regulation. No gender difference was observed in the change of glucose regulation. However, results from an adjusted logistic regression analysis in males showed that physical activity was significantly associated with both elevated odds of reverting to normal glucose regulation (active vs inactive, OR 3.00, 95% CI 1.09 to 8.30) and developing diabetes (OR 0.34, 95% CI 0.13 to 0.92). Age, baseline 2 h glucose, triglycerides and smoking status were also risk factors significantly associated with diabetes development; while for females, waist circumference played a key role in the outcome. Every unit elevation of waist circumference was associated with lower odds of reverting to normal glucose regulation (OR, 0.94; 95% CI 0.89 to 0.98) and higher odds of progressing to diabetes (OR, 1.05; 95% CI 1.01 to 1.10). Baseline hypertension and family history of diabetes carried higher risk for developing diabetes as well.

CONCLUSIONS

Physical activity in males and waist circumference in females are important factors predicting both progression to diabetes and regression to normal glucose regulation, indicating that more exercise for males and lower waist circumference for females are beneficial for prediabetes to achieve reversion.

Expression and therapeutic targeting of dopamine receptor-1 (D1R) in breast cancer

Patients with advanced breast cancer often fail to respond to treatment, creating a need to develop novel biomarkers and effective therapeutics. Dopamine (DA) is a catecholamine that binds to five G protein-coupled receptors. We discovered expression of DA type-1 receptors (D1Rs) in breast cancer, thereby identifying these receptors as novel therapeutic targets in this disease. Strong to moderate immunoreactive D1R expression was found in 30% of 751 primary breast carcinomas, and was associated with larger tumors, higher tumor grades, node metastasis and shorter patient survival. DA and D1R agonists, signaling through the cGMP/protein kinase G (PKG) pathway, suppressed cell viability, inhibited invasion and induced apoptosis in multiple breast cancer cell lines. Fenoldopam, a peripheral D1R agonist that does not penetrate the brain, dramatically suppressed tumor growth in two mouse models with D1R-expressing xenografts by increasing both necrosis and apoptosis. D1R-expressing primary tumors and metastases in mice were detected by fluorescence imaging. In conclusion, D1R overexpression is associated with advanced breast cancer and poor prognosis. Activation of the D1R/cGMP/PKG pathway induces apoptosis in vitro and causes tumor shrinkage in vivo. Fenoldopam, which is FDA (Food and Drug Administration) approved to treat renal hypertension, could be repurposed as a novel therapeutic agent for patients with D1R-expressing tumors.

Preparation of vesicular stomatitis virus pseudotype with Chikungunya virus envelope protein

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that causes Chikungunya fever (CHIKF) in millions of people mainly in developing countries. CHIKF is characterized by high fever, fatigue, headache, nausea, vomiting, rash, myalgia and severe arthralgia. To date, there is no specific treatment and no licensed vaccine against CHIKV infection. In this study, we developed a safe, efficient and easy neutralization assay of CHIKV based on vesicular stomatitis virus (VSV) pseudotype with CHIKV envelope protein and the green fluorescent protein (GFP) or luciferase as reporter gene, which could be used under a reduced safety level. The VSV pseudotype can be applied to the epidemic survey by measuring the expression of GFP or luciferase activity in infected cells. This system can also be used to study the mechanisms of virus entry.

Effects of prediabetes mellitus alone or plus hypertension on subsequent occurrence of cardiovascular disease and diabetes mellitus: longitudinal study

Whether prediabetes mellitus alone or combined with other disorders means a higher risk for cardiovascular disease (CVD) is still controversial. This study aimed to investigate the association between prediabetes mellitus and CVD and diabetes mellitus and to explore whether prediabetes mellitus alone or combined with other syndromes, such as hypertension, could promote CVD risks significantly. This longitudinal population-based study of 1609 residents from Shanghai in Southern China was conducted between 2002 and 2014. Participants with a history of CVD at baseline were excluded from analysis. Multivariate log-binomial regression models were used to adjust possible coexisting factors. Incidence of CVD during follow-up was 10.1%. After adjusting for age, sex, and other factors, the association between prediabetes mellitus and CVD was not observed. When hypertension was incorporated in stratifying factors, adjusted CVD risk was elevated significantly (odds ratio, 2.41; 95% confidence interval, 1.25-4.64) in prediabetes mellitus and hypertension combined group, and coexistence of diabetes mellitus and hypertension made CVD risk highly significantly increased, reaching 3.43-fold higher than the reference group. Blood glucose level within prediabetic range is significantly associated with elevated risks for diabetes mellitus after multivariable adjustment, but only when it is concurrent with other disorders, such as hypertension, it will significantly increase CVD risk.

Quality control metrics improve repeatability and reproducibility of single-nucleotide variants derived from whole-genome sequencing

Although many quality control (QC) methods have been developed to improve the quality of single-nucleotide variants (SNVs) in SNV-calling, QC methods for use subsequent to single-nucleotide polymorphism-calling have not been reported. We developed five QC metrics to improve the quality of SNVs using the whole-genome-sequencing data of a monozygotic twin pair from the Korean Personal Genome Project. The QC metrics improved both repeatability between the monozygotic twin pair and reproducibility between SNV-calling pipelines. We demonstrated the QC metrics improve reproducibility of SNVs derived from not only whole-genome-sequencing data but also whole-exome-sequencing data. The QC metrics are calculated based on the reference genome used in the alignment without accessing the raw and intermediate data or knowing the SNV-calling details. Therefore, the QC metrics can be easily adopted in downstream association analysis.

Cost implications of the use of basal insulin glargine in people with early dysglycemia: the ORIGIN trial

AIMS

The cost implications of the Outcome Reduction with an Initial Glargine Intervention (ORIGIN) trial were evaluated using a prespecified analysis plan.

METHODS

Purchasing power parity-adjusted country-specific costs were applied to consumed healthcare resources by participants from each country. Subgroup analyses were conducted on subgroups based on baseline metabolic status and diabetes duration.

RESULTS

The total undiscounted cost per participant in the insulin glargine arm was $13,491 ($13,080 to $14,254) versus $11,189 ($10,568 to $12,147) for standard care, an increase of $2303 ($1370 to $3235; p < 0.0001); the discounted increase was $2099 ($1276 to $2923; P < 0.0001). The greater number of mainly generic oral anti-diabetic agents in the standard group partially offset the higher cost of basal insulin glargine. As the trial progressed and the standard group required more anti-diabetic medications, the annual cost difference decreased, reaching $68 (-$160 to $295) in the last year. The subgroup whose baseline diabetes duration was ≥ 6 years achieved cost-savings during the trial.

CONCLUSIONS

From a global perspective basal insulin glargine use in ORIGIN incurred greater costs than standard care using older generic drugs. Nevertheless, the cost difference fell with time such that the intervention was cost-neutral by the last year.

DNA methylation of membrane-bound tyrosine phosphatase genes in acute lymphoblastic leukaemia

Aberrant DNA promoter methylation with associated gene silencing is a common epigenetic abnormality in acute lymphoblastic leukaemia (ALL) and is associated with poor survival. We have identified a family of transmembrane tyrosine phosphatase proteins as targets of hypermethylation in ALL and high-grade B cell lymphoma and demonstrated that this abnormal methylation correlates with transcript expression. PTPRG was methylated in 63% of ALL samples, PTPRK in 47%, PTPRM in 64% and PTPRO in 54% of cases, with most ALL samples containing methylation at multiple phosphatase loci. PTPRK promoter methylation was associated with a decreased overall survival in the cohort. Restoration of PTPRK transcript levels in leukaemia cells, where phosphatase transcript was silenced, reduced cell proliferation, inhibited colony formation and increased sensitivity to cytotoxic chemotherapy. These biological changes were associated with a reduction in levels of phosphorylated Erk1/2, Akt, STAT3 and STAT5 suggesting functional phosphatase activity after transcript re-expression. Methylation of the phosphatase promoters was reversible with decitabine and a histone deacetylase inhibitor, suggesting that PTPRK-mediated cell signalling pathways may be targeted with epigenetic therapies in lymphoid malignancy.

Exploring the FDA adverse event reporting system to generate hypotheses for monitoring of disease characteristics

The US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) is a database for postmarketing drug safety monitoring and influences changes in FDA safety guidance documents such as drug labels. The number of cases in the FAERS has rapidly increased with the improvement of submission methods and data standards and thus has become an important resource for regulatory science. Although the FAERS has been predominantly used for safety signal detection, this study explored its utility for disease characteristics.

European guidelines for quality assurance in colorectal cancer screening and diagnosis: overview and introduction to the full supplement publication

Population-based screening for early detection and treatment of colorectal cancer (CRC) and precursor lesions, using evidence-based methods, can be effective in populations with a significant burden of the disease provided the services are of high quality. Multidisciplinary, evidence-based guidelines for quality assurance in CRC screening and diagnosis have been developed by experts in a project co-financed by the European Union. The 450-page guidelines were published in book format by the European Commission in 2010.  They include 10 chapters and over 250 recommendations, individually graded according to the strength of the recommendation and the supporting evidence. Adoption of the recommendations can improve and maintain the quality and effectiveness of an entire screening process, including identification and invitation of the target population, diagnosis and management of the disease and appropriate surveillance in people with detected lesions. To make the principles, recommendations and standards in the guidelines known to a wider professional and scientific community and to facilitate their use in the scientific literature, the original content is presented in journal format in an open-access Supplement of Endoscopy. The editors have prepared the present overview to inform readers of the comprehensive scope and content of the guidelines.

Bending sensor based on intermodal interference properties of two-dimensional waveguide array fiber

We propose a highly sensitive bending sensor based on the intermodal interference properties of a strongly coupled two-dimentional waveguide array fiber (WAF). The interference resonance peaks formed by the SMF-WAF-SMF Mach-Zehnder interferometer are intrinsically the result of interference between the LP(01)-like supermode and other higher order supermodes, displaying supernormal sensitivity to bending in a wide curvature range. The bending sensitivity of the intermodal MZI is a quadratic function of curvature, and the resonance wavelength shift is up to 100 nm within a curvature range 0-10 m(-1). The fabrication reveals briefness, and temperature response shows little impact on the bend sensing precision. The high bending sensitivity and wide sensing range can make this device a candidate for bending discrimination and measurement in widespread areas.

Associations between metabolic syndrome and its components and alcohol drinking

AIMS

The relationship between alcohol drinking and metabolic syndrome (MetS) and its components are not fully confirmed, we examined relationship between alcohol drinking and MetS and its components.

METHODS

2,538 Mongolian people aged 20 or more were included in this study. The data for demographic characteristics, lifestyle factors, family history of hypertension, blood pressure (BP) measurements and physical examination were obtained, and fasting plasma glucose (FPG) and lipids examined for all participants. Associations between MetS and its components and alcohol drinking were analyzed with Logistic regression.

RESULTS

The risks of MetS associated with alcohol drinking and various drinking volume were not significant after adjustment for other variables. Alcohol drinking was significantly and positively associated with high BP and high TG, the multivariate adjusted OR (95% CI) of high BP and high TG for drinking were 1.399(1.109, 1.764) and 2.464(1.866, 3.252), respectively, compared with no drinking. However, drinking was inversely associated with low HDL-C, the multivariate adjusted OR (95% CI) of low HDL-C was 0.597(0.479, 0.745) for alcohol drinking compared with no drinking.

CONCLUSIONS

Alcohol drinking was significantly and positively associated with high BP and high TG, while alcohol drinking inversely associated with low HDL-C.

Value of CYP3A5 genotyping on determining initial dosages of tacrolimus for Chinese renal transplant recipients

Optimal blood levels of tacrolimus in transplant recipients are critically important to preserve the allograft. Suboptimal doses of the immunosuppressant can result in allograft toxicity or rejection. In the present study, we determined CYP3A5 genotypes of patients and analyzed their medical documents in 2 successive periods. In the first period, a fixed initial dosage of 0.1 mg/kg was prescribed daily for 28 patients regardless of their CYP3A5 genotype. In the second period, CYP3A5 genotyping was performed with polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. The frequency distribution of CYP3A5 genotypes was 47.4% (38/78) for *1/*3, 2.6% (2/78) for *1/*1, and 50% (39/78) for *3/*3. The patients with *1/*3 had shown significantly lower tacrolimus blood levels than those with the *3/*3 when the initial dose of 0.10 mg/kg was given for 2 weeks postoperatively. In the second period, initial dosages were selected according to individuals' CYP3A5 genotypes, 0.08 mg/kg/d for recipients with CYP3A5 *3/*3 and 0.15 mg/kg/d for recipients with *1/*3. Adjustment of the initial dosage of tacrolimus was documented to improve the proportion of patients achieving target drug blood levels in the early postoperative stage: from 46.7% to 81.8% of the *1/*3 group and from 46.2% to 73.1% of the *3/*3 group on the third day. In conclusion, CYP3A5 polymorphism plays an important role in influencing tacrolimus blood levels. Initial tacrolimus dosage selection based on CYP3A5 genotyping can improve drug blood levels in the early stage following renal transplantation.