Metabolic perturbations mediated by propionyl-CoA accumulation in organs of mouse model of propionic acidemia

Propionic acidemia (PA) is an autosomal recessive metabolic disorder after gene encoding propionyl-CoA carboxylase, Pcca or Pccb, is mutated. This genetic disorder could develop various complications which are ascribed to dysregulated propionyl-CoA metabolism in organs. However, the effect of attenuated PCC on propionyl-CoA metabolism in different organs remains to be fully understood. We investigated metabolic perturbations in organs of Pcca^-/-(A138T) mice (a mouse model of PA) under chow diet and acute administration of [¹³C₃]propionate to gain insight into pathological mechanisms of PA. With chow diet, the metabolic alteration is organ dependent. l-Carnitine reduction induced by propionylcarnitine accumulation only occurs in lung and liver of Pcca^-/- (A138T) mice. [¹³C₃]Propionate tracing data demonstrated that PCC activity was dramatically reduced in Pcca^-/-(A138T) brain, lung, liver, kidney, and adipose tissues, but not significantly changed in Pcca^-/-(A138T) muscles (heart and skeletal muscles) and pancreas, which was largely supported by PCCA expression data. The largest expansion of propionylcarnitine in Pcca^-/-(A138T) heart after acute administration of propionate indicated the vulnerability of heart to high circulating propionate. The overwhelming propionate in blood also stimulated ketone production from the increased fatty acid oxidation in Pcca^-/-(A138T) liver by lowering malonyl-CoA, which has been observed in cases where metabolic decompensation occurs in PA patients. This work shed light on organ-specific metabolic alternations under varying severities of PA.

SLC1A5 provides glutamine and asparagine necessary for bone development in mice

Osteoblast differentiation is sequentially characterized by high rates of proliferation followed by increased protein and matrix synthesis, processes that require substantial amino acid acquisition and production. How osteoblasts obtain or maintain intracellular amino acid production is poorly understood. Here, we identify SLC1A5 as a critical amino acid transporter during bone development. Using a genetic and metabolomic approach, we show SLC1A5 acts cell autonomously to regulate protein synthesis and osteoblast differentiation. SLC1A5 provides both glutamine and asparagine which are essential for osteoblast differentiation. Mechanistically, glutamine and to a lesser extent asparagine support amino acid biosynthesis. Thus, osteoblasts depend on Slc1a5 to provide glutamine and asparagine, which are subsequently used to produce non-essential amino acids and support osteoblast differentiation and bone development.

[Mechanism of scavenger receptor-A in high glucose-induced inflammatory injury of mesangial cells]

Objective: To investigate the effect of high glucose on scavenger receptor-A (SR-A) in human glomerular mesangial cells (HMC) and explore the mechanism of inflammatory injury mediated by SR-A in HMC cultured in high-glucose medium. Methods: According to the concentration of D-glucose in culture medium, HMC were divided into normal glucose group (5.5 mmol/L) and high glucose group (30 mmol/L), with mannitol group as hypertonic control. High glucose group was transfected with SR-A small interfering RNA (siSR-A) and the transfection control (siNC) group were set up. Western blotting technology was used to detect the levels of SR-A, NOD-like receptor family pyrin domain-containing 3 (NLRP3), interleukin-1β (IL-1β) protein. Immunofluorescent staining was applied to measure the SR-A in HMC. The mRNA of NLRP3, Caspase-1, IL-1β, FN, ColⅣ, α-SMA and GRP78 were detected by real-time quantitative PCR. The relative activity of Caspase-1 was detected by enzyme method and the concentration of IL-1β in culture medium was detected by enzyme linked immunosorbent assay. Flow cytometry was used to measure the cell cycles of HMC. One-way ANOVA and SNK-q test were used for statistical analysis. Results: The protein level of SR-A in high glucose group was higher than that in normal glucose group and mannitol group (1.23±0.21 vs. 0.68±0.10, 1.23±0.21 vs. 0.78±0.13, all P<0.05). In addition, mean fluorescence intensity of SR-A, protein levels of NLRP3 and IL-1β, mRNA of NLRP3, Caspase-1 and IL-1β, relative activity of Caspase-1 as well as the concentration of IL-1β in high glucose group were all significantly higher than those in normal glucose group and mannitol group (all P<0.05).After transfection induced silencing, SR-A protein in high glucose siNC group was higher than that in high glucose siSR-A group and normal glucose siNC group (1.23±0.10 vs. 0.20±0.01, 1.23±0.10 vs. 0.87±0.01, all P<0.01). In high glucose siNC group, the NLRP3, IL-1β proteins, the NLRP3, Caspase-1 and IL-1β mRNA, all of the mRNA levels of FN, ColⅣ, α-SMA, GRP78 and the proportion of DNA synthesis phase were all higher than those in high glucose siSR-A group and normal glucose siNC group (all P<0.05). Conclusion: High glucose can promote abnormal cell proliferation, increase mesangial matrix production and enhance oxidative stress response through upregulating SR-A expression, and ultimately aggravate cellular inflammatory damage in HMC, which may be associated with NLRP3-Caspase-1-IL-1β pathway regulated by SR-A expression.

Reductive TCA cycle metabolism fuels glutamine- and glucose-stimulated insulin secretion

Metabolic fuels regulate insulin secretion by generating second messengers that drive insulin granule exocytosis, but the biochemical pathways involved are incompletely understood. Here we demonstrate that stimulation of rat insulinoma cells or primary rat islets with glucose or glutamine + 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid (Gln + BCH) induces reductive, "counter-clockwise" tricarboxylic acid (TCA) cycle flux of glutamine to citrate. Molecular or pharmacologic suppression of isocitrate dehydrogenase-2 (IDH2), which catalyzes reductive carboxylation of 2-ketoglutarate to isocitrate, results in impairment of glucose- and Gln + BCH-stimulated reductive TCA cycle flux, lowering of NADPH levels, and inhibition of insulin secretion. Pharmacologic suppression of IDH2 also inhibits insulin secretion in living mice. Reductive TCA cycle flux has been proposed as a mechanism for generation of biomass in cancer cells. Here we demonstrate that reductive TCA cycle flux also produces stimulus-secretion coupling factors that regulate insulin secretion, including in non-dividing cells.

Mutant IDH and non-mutant chondrosarcomas display distinct cellular metabolomes

BACKGROUND

Majority of chondrosarcomas are associated with a number of genetic alterations, including somatic mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 genes, but the downstream effects of these mutated enzymes on cellular metabolism and tumor energetics are unknown. As IDH mutations are likely to be involved in malignant transformation of chondrosarcomas, we aimed to exploit metabolomic changes in IDH mutant and non-mutant chondrosarcomas.

METHODS

Here, we profiled over 69 metabolites in 17 patient-derived xenografts by targeted mass spectrometry to determine if metabolomic differences exist in mutant IDH1, mutant IDH2, and non-mutant chondrosarcomas. UMAP (Uniform Manifold Approximation and Projection) analysis was performed on our dataset to examine potential similarities that may exist between each chondrosarcoma based on genotype.

RESULTS

UMAP revealed that mutant IDH chondrosarcomas possess a distinct metabolic profile compared with non-mutant chondrosarcomas. More specifically, our targeted metabolomics study revealed large-scale differences in organic acid intermediates of the tricarboxylic acid (TCA) cycle, amino acids, and specific acylcarnitines in chondrosarcomas. Lactate and late TCA cycle intermediates were elevated in mutant IDH chondrosarcomas, suggestive of increased glycolytic metabolism and possible anaplerotic influx to the TCA cycle. A broad elevation of amino acids was found in mutant IDH chondrosarcomas. A few acylcarnitines of varying carbon chain lengths were also elevated in mutant IDH chondrosarcomas, but with minimal clustering in accordance with tumor genotype. Analysis of previously published gene expression profiling revealed increased expression of several metabolism genes in mutant IDH chondrosarcomas, which also correlated to patient survival.

CONCLUSIONS

Overall, our findings suggest that IDH mutations induce global metabolic changes in chondrosarcomas and shed light on deranged metabolic pathways.

Branched-chain α-ketoacids are preferentially reaminated and activate protein synthesis in the heart

Branched-chain amino acids (BCAA) and their cognate α-ketoacids (BCKA) are elevated in an array of cardiometabolic diseases. Here we demonstrate that the major metabolic fate of uniformly-¹³C-labeled α-ketoisovalerate ([U-¹³C]KIV) in the heart is reamination to valine. Activation of cardiac branched-chain α-ketoacid dehydrogenase (BCKDH) by treatment with the BCKDH kinase inhibitor, BT2, does not impede the strong flux of [U-¹³C]KIV to valine. Sequestration of BCAA and BCKA away from mitochondrial oxidation is likely due to low levels of expression of the mitochondrial BCAA transporter SLC25A44 in the heart, as its overexpression significantly lowers accumulation of [¹³C]-labeled valine from [U-¹³C]KIV. Finally, exposure of perfused hearts to levels of BCKA found in obese rats increases phosphorylation of the translational repressor 4E-BP1 as well as multiple proteins in the MEK-ERK pathway, leading to a doubling of total protein synthesis. These data suggest that elevated BCKA levels found in obesity may contribute to pathologic cardiac hypertrophy via chronic activation of protein synthesis.

Systemic modulation of branched-chain keto acid (BCKA) metabolism alters cardiac health. Here, the authors define the major fates of BCKA in the heart and demonstrate that acute exposure to BCKA levels found in obesity activates cardiac protein synthesis and markedly alters the heart phosphoproteome.

Structural variability and differentiation of niches in the rhizosphere and endosphere bacterial microbiome of moso bamboo (Phyllostachys edulis)

The plant microbiota play a key role in plant productivity, nutrient uptake, resistance to stress and flowering. The flowering of moso bamboo has been a focus of study. The mechanism of flowering is related to nutrient uptake, temperature, hormone balance and regulation of key genes. However, the connection between microbiota of moso bamboo and its flowering is unknown. In this study, samples of rhizosphere soil, rhizomes, roots and leaves of flowering and nonflowering plants were collected, and 16S rRNA amplicon Illumina sequencing was utilized to separate the bacterial communities associated with different flowering stages of moso bamboo. We identified 5442 OTUs, and the number of rhizosphere soil OTUs was much higher than those of other samples. Principal component analysis (PCA) and hierarchical clustering (Bray Curtis dis) analysis revealed that the bacterial microorganisms related to rhizosphere soil and endophytic tissues of moso bamboo differed significantly from those in bulk soil and rhizobacterial and endosphere microbiomes. In addition, the PCA analyses of root and rhizosphere soil revealed different structures of microbial communities between bamboo that is flowering and not flowering. Through the analysis of core microorganisms, it was found that Flavobacterium, Bacillus and Stenotrophomonas played an important role in the absorption of N elements, which may affect the flowering time of moso bamboo. Our results delineate the complex host-microbe interactions of this plant. We also discuss the potential influence of bacterial microbiome in flowering, which can provide a basis for the development and utilization of moso bamboo.

Measuring acetyl-CoA and acetylated histone turnover in vivo: Effect of a high fat diet

Cellular availability of acetyl-CoA, a central intermediate of metabolism, regulates histone acetylation. The impact of a high-fat diet (HFD) on the turnover rates of acetyl-CoA and acetylated histones is unknown. We developed a method for simultaneous measurement of acetyl-CoA and acetylated histones kinetics using a single ²H₂O tracer, and used it to examine effect of HFD-induced perturbations on hepatic histone acetylation in LDLR^-/- mice, a mouse model of non-alcoholic fatty liver disease (NAFLD). Mice were given ²H₂O in the drinking water and the kinetics of hepatic acetyl-CoA, histones, and acetylated histones were quantified based on their ²H-labeling. Consumption of a high fat Western-diet (WD) for twelve weeks led to decreased acetylation of hepatic histones (p< 0.05), as compared to a control diet. These changes were associated with 1.5-3-fold increased turnover rates of histones without any change in acetyl-CoA flux. Acetylation significantly reduced the stability of histones and the turnover rates of acetylated peptides were correlated with the number of acetyl groups in neighboring lysine sites. We conclude that ²H₂O-method can be used to study metabolically controlled histone acetylation and acetylated histone turnover in vivo.

[Meta-analysis of clinical effects of microskin grafting and Meek microskin grafting in repairing extensively deep burn wounds]

Objective: To systematically evaluate the clinical effects of microskin grafting and Meek microskin grafting in repairing extensively deep burn wounds using meta-analysis. Methods: Foreign language databases including PubMed and Cochrane Library were searched with the terms of " Meek micrografting, burn" , and Chinese databases including Chinese Journal Full-Text Database, Chinese Biomedical Database, VIP database, and Wanfang Data were searched with the terms in Chinese version of ", Meek," to retrieve the publicly published randomized controlled trials on the microskin grafting and Meek microskin grafting in repairing extensively deep burn wounds from the establishment of each database to March 20, 2019. The outcome indexes included the survival rate of skin graft, primary healing rate, operation time, and surgical treatment cost after the first operation, as well as the wound healing time and length of hospital stay. RevMan 5.3 and Stata 14.0 statistical software were used to conduct a meta-analysis of eligible studies. Results: A total of 821 patients with extensively deep burns were included in 15 studies, including 410 patients in microskin group who received microskin grafting and 411 patients in Meek microskin group who received Meek microskin grafting. The bias risks of the 15 studies included were uncertain. Compared with those of microskin group, the survival rate of skin graft and primary healing rate of patients in Meek microskin group were significantly increased, with relative risks of 0.76 and 0.66 (95% confidence interval=0.66-0.88, 0.50-0.88, P<0.01), the surgical treatment cost was significantly reduced, with a standardized mean difference of 3.19 (95% confidence interval=1.36-5.01, P<0.01), and the operation time, wound healing time, and length of hospital stay were significantly shortened, with standardized mean differences of 6.05, 2.39, and 2.35 (95% confidence interval=3.66-8.44, 1.43-3.35, 2.03-2.68, P<0.01). Subgroup analysis showed that microskin grafting combined with allogenic skin graft might be a heterogeneous source of operation time. Sensitivity analysis showed that the combined effect size was stable in the operation time, surgical treatment cost, and wound healing time. There was no publication bias in the survival rate of skin graft, operation time, wound healing time, and length of hospital stay (P>0.05), while the primary healing rate and surgical treatment cost had publication bias (P<0.01). Conclusions: Compared with microskin grafting, Meek microskin grafting improves the rates of skin graft survival and primary healing, shortens operation time, wound healing time, and length of hospital stay, and reduces the treatment cost in treating extensively deep burn wounds.

Author Correction: Combination of ERK and autophagy inhibition as a treatment approach for pancreatic cancer

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

[Clinical characteristics and influencing factors of patients with novel coronavirus pneumonia combined with liver injury in Shaanxi region]

Objective: To understand the clinical characteristics, change of liver function, influencing factors and prognosis in hospitalized patients with coronavirus disease-19 (COVID-19) combined with liver injury. Methods: The general conditions, biochemical indicators of liver, blood clotting mechanism, routine blood test, UGT1A1 * 28 gene polymorphism and other data of 40 cases with COVID-19 admitted to the isolation ward of Tangdu Hospital were retrospectively analyzed. The clinical characteristics, influencing factors and prognosis of liver injury in patients with liver injury group and those with normal liver function group were compared. The mean of two samples in univariate analysis was compared by t-test and analysis of variance. The counting data was measured by χ(2) tests. The non-normal distribution measurement data were described by the median, and the non-parametric test was used. Statistically significant influencing factors were used as the independent variables in univariate analysis. Multiple logistic regression analysis was used to analyze the main influencing factors of liver injury. Results: Of the 40 cases, 25 were male (62.5%) and 15 were female (37.5%), aged 22 to 83 (53.87 ± 15.84) years. Liver injury was occurred in 22 cases (55%) during the course of the disease. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level was initially increased (4.4 to 3.5 times of the normal value) along with decrease of albumin in the second week, and the difference was statistically significant (P < 0.001). Ten cases (43.5%) had highest abnormal total blood bilirubin (54.1 μmol/ L). There was no correlation between the increase in transaminase and the increase in total blood bilirubin (R = -0.006, P = 0.972). Three cases had prothrombin activity (PTA) of ≤50%, 10 cases had elevated FDP, and 13 cases had elevated D-dimer, all of whom were severe or critically ill. Liver function injury was more likely to occur in patients who used many types of drugs and large amounts of hormones (P = 0.002, P = 0.031), and there was no correlation with the TA6TA7 mutation in the UGT1A1 * 28 gene locus. Multiple regression analysis showed that the occurrence of liver injury was only related to critical illness. The liver function of all patients had recovered within one week after conventional liver protection treatment. Conclusion: COVID-19 combined with liver function injury may be due to the slight elevation of transaminase, mostly around the second week of the disease course. Severe patients have a higher proportion of liver injury, and critical type is an independent risk factor for liver injury.

Dietary branched-chain amino acid restriction alters fuel selection and reduces triglyceride stores in hearts of Zucker fatty rats

Elevations in circulating levels of branched-chain amino acids (BCAAs) are associated with a variety of cardiometabolic diseases and conditions. Restriction of dietary BCAAs in rodent models of obesity lowers circulating BCAA levels and improves whole-animal and skeletal-muscle insulin sensitivity and lipid homeostasis, but the impact of BCAA supply on heart metabolism has not been studied. Here, we report that feeding a BCAA-restricted chow diet to Zucker fatty rats (ZFRs) causes a shift in cardiac fuel metabolism that favors fatty acid relative to glucose catabolism. This is illustrated by an increase in labeling of acetyl-CoA from [1-¹³C]palmitate and a decrease in labeling of acetyl-CoA and malonyl-CoA from [U-¹³C]glucose, accompanied by a decrease in cardiac hexokinase II and glucose transporter 4 protein levels. Metabolomic profiling of heart tissue supports these findings by demonstrating an increase in levels of a host of fatty-acid-derived metabolites in hearts from ZFRs and Zucker lean rats (ZLRs) fed the BCAA-restricted diet. In addition, the twofold increase in cardiac triglyceride stores in ZFRs compared with ZLRs fed on chow diet is eliminated in ZFRs fed on the BCAA-restricted diet. Finally, the enzymatic activity of branched-chain ketoacid dehydrogenase (BCKDH) is not influenced by BCAA restriction, and levels of BCAA in the heart instead reflect their levels in circulation. In summary, reducing BCAA supply in obesity improves cardiac metabolic health by a mechanism independent of alterations in BCKDH activity.

[Long-term efficacy analysis of laparoscopic-assisted anorectoplasty for high and middle imperforate anus]

Objective: To explore the long-term efficacy of laparoscopic-assisted anorectoplasty and conventional anorectoplasty in the treatment of children with high and middle anal atresia. Methods: A retrospective cohort study was used. Inclusion criteria: (1) children with high and middle anal atresia; (2) complicated with rectourethral or rectovesical fistula; (3) complete follow-up data. Exclusion criteria: (1) complicated with 21-trisomy; (2) cerebral palsy and other mentaldisabilities; (3) Currarino syndrome; (4) FG syndrome. Clinical data of 88 patients with middle and high anal atresia, who complicated with rectourethral fistula or rectovesical fistula, and underwent anoplasty at Department of Pediatric Surgery, the First Affiliated Hospital of Zhengzhou University from January 2009 to June 2014 were enrolled in the study and analyzed. There were 24 cases with middle atresia and 64 cases with high atresia. All the cases were divided into 2 groups based on the operative method: laparoscopic group (laparoscopic-assisted anorectoplasty, 49 cases), pena group (posterior sagittal anorectoplasty, 39 cases). The demographic features of two groups were comparable. There were no statistically significant differences in gender, age, body mass, classification of anomaly types and sacral ratio (all P>0.05). Student t test and Chi square tests were used to compare the surgical conditions (operative time, postoperative hospital stay and complications), anal function (Kelly score), constipation (Krickenbeck constipation score) and anorectal pressure. Results: Children of both groups all completed operation ssuccessfully. There were no statistically significant differences between laparoscopic group and pena group in the operative time [(120±31) minutes vs. (112±23) minutes, t=1.343, P=0.091] and postoperative hospital stay [(7.1±2.3) days vs. (10.7±3.3) days, t=6.021, P=1.000]. Complications were more common in the pena group [16.3% (8/49) vs. 35.9% (14/39), χ(2)=4.436, P=0.035]. The main complications in laparoscopic group were anal prolapse (8.2%, 4/49) and anal stenosis (6.2%, 3/49), while in pena group were anal stenosis (12.8%, 5/39) and perioperative perianal skin erosion (10.3%, 4/39). As for the anal function, the degree of feces, defecation control and sphincter contractility, the single scoring differences of Kelly scoring system were not statistically significant between the two groups, but the proportion of good function in the laparoscopic group was higher than that in the pena group [67.3% (8/49) vs. 38.5% (15/39), χ(2)=7.308, P=0.007]. Constipation occurred in 6 (12.2%) patients in the laparoscopic group, of whom 5 were improved by diet regulation and 1 required laxatives, while 9 (23.1%) patients developed constipation in the pena group, of whom 4 were improved by diet regulation and 5 required long-term laxatives. The difference of constipation ratio was not statistically significant (χ(2)=1.802, P=0.180). There were no cases of Krickenbeck constipation grade 3. Compared to the pena group, the laparoscopic group had higher anal resting pressure [(33.35±9.69) mmHg vs. (27.68±10.74) mmHg, t=2.599, P=0.011], higher dilating pressure [(9.00±5.61) mmHg vs.(6.51±3.24) mmHg, t=2.462, P=0.016], higher maximal squeeze pressure [(65.80±17.23) mmHg vs. (56.74±18.93) mmHg, t=2.389, P=0.019] and longer maximal contraction time [(21.16±5.02) seconds vs. (18.44±7.24) seconds, t=2.079, P=0.041]. The rectal resting pressure [(5.36±3.00) mmHg vs. (4.61±3.93) mmHg, t=1.015, P=0.312] was not statistically significantly different. Conclusions: Compared with posterior sagittal anorectoplasty, laparoscopic-assisted anorectoplasty in the treatment of high and middle anal atresia has better long-term efficacy with less perioperative complications.

[Quantitative study on the development of fetal ventricles and cisterna magna in second and third trimesters with MRI]

Objective: To analyze the changes of growth and development of normal fetal ventricles and cisterna magna with gestational age(GA) and the correlation with fetal gender in the second and third trimester,and establish the MR prenatal diagnosis reference standards. Methods: A total of 633 fetuses (mean GA (27.0±4.1) weeks (18.9-40.6 weeks))without central nervous system abnormalities were retrospectively collected from the Obstetrics and Gynecology Hospital of Fudan University from June 2012 to August 2017. The lateral ventricle trigonometric width (LVTW), third ventricle width (TVW), fourth ventricle width (FVW), anterior-posterior diameter of the fourth ventricle(APDFV), cavum septum pellucidum width (CSPW) and cisterna magna width (CMW) were obtained in the standard measure planes on MR image.The correlation between the biometrics and GA and the correlation between the biometrics and fetal gender were analyzed respectively, and the normal reference values of the biometrics were calculated. Spearman correlation analysis, Pearson correlation analysis,linear regression analysis, independent samples t-test and paired samples t-test were used for statistic analysis. Results: (1)Fetal LLVTW,RLVTW,TVW,CSPW and CMW in second and third trimesters were correlated with GA at medium and low levels(the correlation coefficient r were 0.311, 0.277, 0.207, 0.226, 0.295, respectively, all P<0.01). FVW and APDFV were statistically correlated with GA, and the linear regression equations were as follows: y=0.022×GA-0.043 (adjusted R(2)=0.642); y=0.018×GA-0.159 (adjusted R(2)=0.690). (2)Fetal LLVTW,RLVTW,FVW,APDFV and CSPW were not correlated with fetal gender in second and third trimesters(r=-0.078,-0.057,-0.087,-0.004 and 0.024, P=0.124,0.258,0.085,0.931 and 0.618, all P>0.05). TVW and CMW were statistically correlated with fetal gender(r=-0.310, -0.180, P=0.000, 0.006, all P<0.05). (3) The mean values of LLVTW and RLVTW were (0.71±0.13) cm and (0.68±0.13) cm, respectively, and significant difference was found between them(t=3.180, P=0.002). The mean value of CSPW was (0.59±0.15) cm. And the mean values of male and female fetuses for TVW and CMW were (0.17±0.05) cm, (0.16±0.06) cm and (0.68±0.15) cm, (0.58±0.15) cm, respectively. The corresponding prenatal MRI diagnostic criteria were as follows: LLVTW 1.1 cm, RLVTW 1.0 cm, CSPW 1.0 cm, TVW 0.3 cm, CMW (male 1.1 cm, female 1.0 cm). Conclusions: The normal fetal ventricles and cisterna magna are increased with the GA in the second and third trimesters. TVW and CMW are related to fetal gender. The establishment of normal reference values of fetal ventricles and cisterna magna based on GA and fetal gender are conducive to enhance the accuracy of MRI prenatal diagnosis.

Glutamine Metabolism Regulates Proliferation and Lineage Allocation in Skeletal Stem Cells

Skeletal stem cells (SSCs) are postulated to provide a continuous supply of osteoblasts throughout life. However, under certain conditions, the SSC population can become incorrectly specified or is not maintained, resulting in reduced osteoblast formation, decreased bone mass, and in severe cases, osteoporosis. Glutamine metabolism has emerged as a critical regulator of many cellular processes in diverse pathologies. The enzyme glutaminase (GLS) deaminates glutamine to form glutamate-the rate-limiting first step in glutamine metabolism. Using genetic and metabolic approaches, we demonstrate GLS and glutamine metabolism are required in SSCs to regulate osteoblast and adipocyte specification and bone formation. Mechanistically, transaminase-dependent α-ketoglutarate production is critical for the proliferation, specification, and differentiation of SSCs. Collectively, these data suggest stimulating GLS activity may provide a therapeutic approach to expand SSCs in aged individuals and enhance osteoblast differentiation and activity to increase bone mass.

Combination of ERK and autophagy inhibition as a treatment approach for pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is characterized by KRAS- and autophagy-dependent tumorigenic growth, but the role of KRAS in supporting autophagy has not been established. We show that, to our surprise, suppression of KRAS increased autophagic flux, as did pharmacological inhibition of its effector ERK MAPK. Furthermore, we demonstrate that either KRAS suppression or ERK inhibition decreased both glycolytic and mitochondrial functions. We speculated that ERK inhibition might thus enhance PDAC dependence on autophagy, in part by impairing other KRAS- or ERK-driven metabolic processes. Accordingly, we found that the autophagy inhibitor chloroquine and genetic or pharmacologic inhibition of specific autophagy regulators synergistically enhanced the ability of ERK inhibitors to mediate antitumor activity in KRAS-driven PDAC. We conclude that combinations of pharmacologic inhibitors that concurrently block both ERK MAPK and autophagic processes that are upregulated in response to ERK inhibition may be effective treatments for PDAC.

[Expression of type 1 and type 2 cytokines from serum of coal miners and the evaluation in surveillance of coal workers' pneumoconiosis at earlier stage]

Objectives: To explore the expression regulation of type 1 and type 2 (Th1 and Th2) cytokines from serum of coal miners and the evaluation in surveillance of coal workers' pneumoconiosis, 630 coal miners were studied. Methods: A total of 90 male patients diagnosed as coal workers' pneumoconiosis (CWP) in a institute for occupational health and 19 male workers newly diagnosed as CWP patients was chosen as CWP group with simple random sampling method from a coal mine group from January 2013 to December in 2015. 180 male coal miners with abnormal but not diagnosed as CWP were selected as CWP suspected group with simple random sampling methods, meanwhile 180 male coal miners with normal chest X-ray photograph was as dust-exposed group by 1∶1 matched as age. And 161 healthy males accepted pre-employed examination were selected as control group, CWP suspected group, dust-exposed group and control group called as non-CWP group. According to screening test and diagnosis test, the basic information and occupational history of all subjects were collected, and cytokines including IL-1β, IL-8, IFN-γ, IL-6 and IL-10 of serum were detected. Receiver operator characteristic (ROC) curve was used to determine the optimal cutoff value of each cytokine. Area under curve (AUC), the validity and reliability were calculated and judged. Results: The average age of control group, dust-exposed group, CWP suspected group and CWP group were (27.4±5.0) , (43.4±10.7) , (48.2±6.2) , (64.7±7.0) years old, respectively. The median level of IL-1β, IL-8, IFN-γ and IL-6 in cases group (1 638.30, 2 099.49, 815.18,140.32 pg/ml) were higher than that of non-cases group (1 445.57, 1 402.26, 736.38, 95.73 pg/ml) (P<0.05) . The level of IL-8 (1 503.99 pg/ml) in CWP suspected group was higher than that of control group (1 295.67 pg/ml) and dust-exposed group (1 376.94 pg/ml) , but the level of IL-10 (654.08 pg/ml) was lower than that of control group (596.64 pg/ml) . The ratio of IFN-γ/IL-6 ranged from 5 to 8, and the ratio in CWP group (5.87) was lower than that of non-CWP group (7.61) . The IL-6 and IL-8 among the subjects of dust-exposed group in terms of the age distribution of among had reached statistical significance. According to ROC, the cutoff value of IL-1β, IL-6, IL-8, IL-10 and INF-γ reached 1 582.65, 116.53, 1 791.54, 581.08 and 792.69 pg/ml, respectively. The AUC was 0.668, 0.895, 0.859, 0.716 and 0.637, respectively. It was found that IL-6 and IL-8 could be used as biomarkers in detecting CWP, the sensitivity and specificity was 82.6% and 84.6%, 78.0% and 84.8%, respectively; Youden's index was 0.674 and 0.628 and the consistency rate was 84.3% and 83.7%, while Kappa value was 0.55 and 0.52. Conclusion: There was Type 1 and type 2 cytokine dysregulation in CWP patients. IL-6 and IL-8 can be used as effective biomarkers to forecast lung injury before X-ray changes.

Propionate-induced changes in cardiac metabolism, notably CoA trapping, are not altered by l-carnitine

High concentrations of propionate and its metabolites are found in several diseases that are often associated with the development of cardiac dysfunction, such as obesity, diabetes, propionic acidemia, and methylmalonic acidemia. In the present work, we employed a stable isotope-based metabolic flux approach to understand propionate-mediated perturbation of cardiac energy metabolism. Propionate led to accumulation of propionyl-CoA (increased by ~101-fold) and methylmalonyl-CoA (increased by 36-fold). This accumulation caused significant mitochondrial CoA trapping and inhibited fatty acid oxidation. The reduced energy contribution from fatty acid oxidation was associated with increased glucose oxidation. The enhanced anaplerosis of propionate and CoA trapping altered the pool sizes of tricarboxylic acid cycle (TCA) metabolites. In addition to being an anaplerotic substrate, the accumulation of proprionate-derived malate increased the recycling of malate to pyruvate and acetyl-CoA, which can enter the TCA for energy production. Supplementation of 3 mM l-carnitine did not relieve CoA trapping and did not reverse the propionate-mediated fuel switch. This is due to new findings that the heart appears to lack the specific enzyme catalyzing the conversion of short-chain (C₃ and C₄) dicarboxylyl-CoAs to dicarboxylylcarnitines. The discovery of this work warrants further investigation on the relevance of dicarboxylylcarnitines, especially C₃ and C₄ dicarboxylylcarnitines, in cardiac conditions such as heart failure.

Quantifying ceramide kinetics in vivo using stable isotope tracers and LC-MS/MS

Numerous studies have implicated dyslipidemia as a key factor in mediating insulin resistance. Ceramides have received special attention since their levels are inversely associated with normal insulin signaling and positively associated with factors that are involved in cardiometabolic disease. Despite the growing literature surrounding ceramide biology, there are limited data regarding the activity of ceramide synthesis and turnover in vivo. Herein, we demonstrate the ability to measure ceramide kinetics by coupling the administration of [²H]water with LC-MS/MS analyses. As a "proof-of-concept" we determined the effect of a diet-induced alteration on ceramide flux; studies also examined the effect of myriocin (a known inhibitor of serine palmitoyltransferase, the first step in sphingosine biosynthesis). Our data suggest that one can estimate ceramide synthesis and draw conclusions regarding the source of fatty acids; we discuss caveats in regards to method development in this area.

[Application of chest CT scan in gestational trophoblastic neoplasia with lung metastasis]

Objective: To explore the role of CT scan for the diagnosis of lung metastasis in stage Ⅲ gestational trophoblastic neoplasia (GTN) . Methods: To figure out the role of CT scan for lung metastasis in GTN initial diagnosis, treatment and follow-up, 93 GTN patients with lung metastasis from January, 2015 to December, 2016 were retrospectively analyzed in Obstetrics and Gynecology Hospital of Fudan University. Results: (1) Among 93 GTN patients with lung metastasis, 70 patients with the International Federation of Gynecology and Obstetrics (FIGO) score ≤6 were defined as low risk GTN and 23 patients score score ≥7 were defined as high risk GTN. Forty nine patients had negative chest X-ray findings and 39 cases with pulmonary lesions were identified both by chest X-ray compared to CT scan. Five cases were excluded due to no consensus could make for the results of chest X-ray. The true positive rate of chest X-ray for lung metastasis were 41% (29/70) in low risk GTN and 43% (10/23) in high risk GTN patients without statistical difference (χ(2)=0.090, P=0.925) . For those patients with positive chest CT scan and negative chest X-ray finding, pulmonary lesions in 32 (65%, 32/49) cases were blocked by heart, chest wall or diaphragm in chest X-ray. Seventeen (35%,17/49) patients with lung lesions less than 5 mm had negative chest X-ray results due to the lower sensitivity compared to CT scan. (2) In 88 patients with stage Ⅲ, 78 patients had successful initial treatment, but 4 of them were recurrence in twelve months follow-up. Ten patients were chemotherapy resistance for the initial treatment. The initial chemotherapy remission rate in low risk GTN patients was higher than that in high risk ones (χ(2)=4.911, P=0.027) . In 49 cases with negative chest X-ray, there was no correlation with the rate of remission,chemotherapy resistance and recurrence in stage Ⅲ patients (P>0.05) . (3) For those patients who had poorly response to initial chemotherapy, the diameters of lesions in lung were unchanged or increased during the treatment, form (5.1±4.1) mm to (7.4±2.8) mm. The pulmonary lesions were continuously shrunk from (7.8±5.3) mm to (4.7±4.4) mm for those patients with complete and partial remission including the recurrent GTN patients (Z=-2.713, P=0.007) . Conclusions: Patients with GTN in stage Ⅲ have down staging if only use chest X-ray for imaging at the initial diagnosis. Chest CT scan is recommended for primary imaging evaluation of FIGO staging in qualified medical organization. For those patients with persistent abnormal serum hCG level and negative chest X-ray, chest CT scan is strongly recommended to identify the persist or resistant lung lesions and follow up.

The BCKDH Kinase and Phosphatase Integrate BCAA and Lipid Metabolism via Regulation of ATP-Citrate Lyase

Branched-chain amino acids (BCAA) are strongly associated with dysregulated glucose and lipid metabolism, but the underlying mechanisms are poorly understood. We report that inhibition of the kinase (BDK) or overexpression of the phosphatase (PPM1K) that regulates branched-chain ketoacid dehydrogenase (BCKDH), the committed step of BCAA catabolism, lowers circulating BCAA, reduces hepatic steatosis, and improves glucose tolerance in the absence of weight loss in Zucker fatty rats. Phosphoproteomics analysis identified ATP-citrate lyase (ACL) as an alternate substrate of BDK and PPM1K. Hepatic overexpression of BDK increased ACL phosphorylation and activated de novo lipogenesis. BDK and PPM1K transcript levels were increased and repressed, respectively, in response to fructose feeding or expression of the ChREBP-β transcription factor. These studies identify BDK and PPM1K as a ChREBP-regulated node that integrates BCAA and lipid metabolism. Moreover, manipulation of the BDK:PPM1K ratio relieves key metabolic disease phenotypes in a genetic model of severe obesity.

Aldolase B-Mediated Fructose Metabolism Drives Metabolic Reprogramming of Colon Cancer Liver Metastasis

Cancer metastasis accounts for the majority of cancer-related deaths and remains a clinical challenge. Metastatic cancer cells generally resemble cells of the primary cancer, but they may be influenced by the milieu of the organs they colonize. Here, we show that colorectal cancer cells undergo metabolic reprogramming after they metastasize and colonize the liver, a key metabolic organ. In particular, via GATA6, metastatic cells in the liver upregulate the enzyme aldolase B (ALDOB), which enhances fructose metabolism and provides fuel for major pathways of central carbon metabolism during tumor cell proliferation. Targeting ALDOB or reducing dietary fructose significantly reduces liver metastatic growth but has little effect on the primary tumor. Our findings suggest that metastatic cells can take advantage of reprogrammed metabolism in their new microenvironment, especially in a metabolically active organ such as the liver. Manipulation of involved pathways may affect the course of metastatic growth.

Cardiovascular Metabolomics

Disturbances in cardiac metabolism underlie most cardiovascular diseases. Metabolomics, one of the newer omics technologies, has emerged as a powerful tool for defining changes in both global and cardiac-specific metabolism that occur across a spectrum of cardiovascular disease states. Findings from metabolomics studies have contributed to better understanding of the metabolic changes that occur in heart failure and ischemic heart disease and have identified new cardiovascular disease biomarkers. As technologies advance, the metabolomics field continues to evolve rapidly. In this review, we will discuss the current state of metabolomics technologies, including consideration of various metabolomics platforms and elements of study design; the emerging utility of stable isotopes for metabolic flux studies; and the use of metabolomics to better understand specific cardiovascular diseases, with an emphasis on recent advances in the field.

The growth-promoting effects of endophytic bacteria on Phyllostachys edulis

The research results of the growth-promoting effects of endophytic bacteria on Phyllostachys edulis indicated that the growth-promoting endophytic bacteria could improve photosynthesis in P. edulis leaves. The photosynthetic rate, transpiration rate, and the stomatal conductance in P. edulis treated with endophytic bacteria were all higher than in the control group. Endophytic bacteria could also increase the chlorophyll content and the protective enzyme activities in P. edulis, improving their reactions to the adverse environmental conditions. Through injection treatments with growth-promoting endophytic bacteria, the catalase, superoxide dismutase (SOD), peroxidase activity, soluble protein content, and soluble sugar content in P. edulis were all higher than in the control group, except for the malondialdehyde content, which was lower than in the control group.

Inter-relations between 3-hydroxypropionate and propionate metabolism in rat liver: relevance to disorders of propionyl-CoA metabolism

Propionate, 3-hydroxypropionate (3HP), methylcitrate, related compounds, and ammonium accumulate in body fluids of patients with disorders of propionyl-CoA metabolism, such as propionic acidemia. Although liver transplantation alleviates hyperammonemia, high concentrations of propionate, 3HP, and methylcitrate persist in body fluids. We hypothesized that conserved metabolic perturbations occurring in transplanted patients result from the simultaneous presence of propionate and 3HP in body fluids. We investigated the inter-relations of propionate and 3HP metabolism in perfused livers from normal rats using metabolomic and stable isotopic technologies. In the presence of propionate, 3HP, or both, we observed the following metabolic perturbations. First, the citric acid cycle (CAC) is overloaded but does not provide sufficient reducing equivalents to the respiratory chain to maintain the homeostasis of adenine nucleotides. Second, there is major CoA trapping in the propionyl-CoA pathway and a tripling of liver total CoA within 1 h. Third, liver proteolysis is stimulated. Fourth, propionate inhibits the conversion of 3HP to acetyl-CoA and its oxidation in the CAC. Fifth, some propionate and some 3HP are converted to nephrotoxic maleate by different processes. Our data have implications for the clinical management of propionic acidemia. They also emphasize the perturbations of the liver intermediary metabolism induced by supraphysiological, i.e., millimolar, concentrations of labeled propionate used to trace the intermediary metabolism, in particular, inhibition of CAC flux and major decreases in the [ATP]/[ADP] and [ATP]/[AMP] ratios.