Insulin reduces pyroptosis-induced inflammation by PDHA1 dephosphorylation-mediated NLRP3 activation during myocardial ischemia-reperfusion injury

BACKGROUND

Previous studies proved that pyrin domain-containing protein 3 (NLRP3)-induced pyroptosis plays an important role in Myocardial ischemia-reperfusion injury (MIRI). Insulin can inhibit the activation of NLRP3 inflammasome, although the exact mechanism remains unclear. The aim of this study was to determine whether insulin reduces NLRP3-induced pyroptosis by regulating pyruvate dehydrogenase E1alpha subunit (PDHA1) dephosphorylation during MIRI.

METHODS

Rat hearts were subject to 30 min global ischemia followed by 60 min reperfusion, with or without 0.5 IU/L insulin. Myocardial ischemia-reperfusion injury was evaluated by measuring myocardial enzymes release, Cardiac hemodynamics, pathological changes, infarct size, and apoptosis rate. Cardiac aerobic glycolysis was evaluated by measuring ATP, lactic acid content, and pyruvate dehydrogenase complex (PDHc) activity in myocardial tissue. Recombinant adenoviral vectors for PDHA1 knockdown were constructed. Pyroptosis-related proteins were measured by Western blotting analysis, immunohistochemistry staining, and ELISA assay, respectively.

RESULTS

It was found that insulin significantly reduced the area of myocardial infarction, apoptosis rate, and improved cardiac hemodynamics, pathological changes, energy metabolism. Insulin inhibits pyroptosis-induced inflammation during MIRI. Subsequently, Adeno-associated virus was used to knock down cardiac PDHA1 expression. Knockdown PDHA1 not only promoted the expression of NLRP3 but also blocked the inhibitory effect of insulin on NLRP3-mediated pyroptosis in MIRI.

CONCLUSIONS

Results suggest that insulin protects against MIRI by regulating PDHA1 dephosphorylation, its mechanism is not only to improve myocardial energy metabolism but also to reduce the NLRP3-induced pyroptosis.

PDHA1 Alleviates Myocardial Ischemia-Reperfusion Injury by Improving Myocardial Insulin Resistance During Cardiopulmonary Bypass Surgery in Rats

OBJECTIVE

Cardiopulmonary bypass (CPB) is a requisite technique for thoracotomy in advanced cardiovascular surgery. However, the consequent myocardial ischemia-reperfusion injury (MIRI) is the primary culprit behind cardiac dysfunction and fatal consequences post-operation. Prior research has posited that myocardial insulin resistance (IR) plays a vital role in exacerbating the progression of MIRI. Nonetheless, the exact mechanisms underlying this phenomenon remain obscure.

METHODS

We constructed pyruvate dehydrogenase E1 α subunit (PDHA1) interference and overexpression rats and used ascending aorta occlusion in an in vivo model of CPB-MIRI. We devised an in vivo model of CPB-MIRI by constructing rat models with both pyruvate dehydrogenase E1α subunit (PDHA1) interference and overexpression through ascending aorta occlusion. We analyzed myocardial glucose metabolism and the degree of myocardial injury using functional monitoring, biochemical assays, and histological analysis.

RESULTS

We discovered a clear downregulation of glucose transporter 4 (GLUT4) protein content expression in the CPB I/R model. In particular, cardiac-specific PDHA1 interference resulted in exacerbated cardiac dysfunction, significantly increased myocardial infarction area, more pronounced myocardial edema, and markedly increased cardiomyocyte apoptosis. Notably, the opposite effect was observed with PDHA1 overexpression, leading to a mitigated cardiac dysfunction and decreased incidence of myocardial infarction post-global ischemia. Mechanistically, PDHA1 plays a crucial role in regulating the protein content expression of GLUT4 on cardiomyocytes, thereby controlling the uptake and utilization of myocardial glucose, influencing the development of myocardial insulin resistance, and ultimately modulating MIRI.

CONCLUSION

Overall, our study sheds new light on the pivotal role of PDHA1 in glucose metabolism and the development of myocardial insulin resistance. Our findings hold promising therapeutic potential for addressing the deleterious effects of MIRI in patients.

[Predictive value of serum lactate dehydrogenase on prognosis of patients with paraquat poisoning]

Objective: To investigate the predictive value of serum lactate dehydrogenase (LDH) in the prognosis of patients with paraquat (PQ) poisoning, and to provide evidence for early prognosis assessment. Methods: In February 2022, 50 patients with PQ poisoning who completed serum LDH detection admitted to the Department of Emergency Medicine, the First Affiliated Hospital of Wenzhou Medical University from January 2012 to December 2021 were selected as the observation group, and 50 healthy physical examination personnel were randomly selected as the control group. Patients with PQ poisoning were divided into survival group and death group according to the prognosis, and the differences of blood routine routine, liver and kidney function and other indicators in the first admission between the two groups were compared. Multivariate logisitic regression model was established, ROC curve was drawn, and the influencing factors of prognosis of patients with PQ poisoning were analyzed. Results: Compared with the control group, the white blood cell count (WBC), total bilirubin (TBil), alanine aminotransferase (ALT), aspartate aminotransferase (AST), LDH, glucose (GLU) and creatinine (Cr) in observation group were significantly increased, while albumin (ALB) and total cholesterol (TC) were significantly decreased (P<0.05). Univariate analysis showed that WBC, elevated LDH (>247 U/L), TBil, ALT, AST and Cr were significantly different between PQ poisoning survival group and death group (P<0.05). Multivariate logisitic regression analysis showed that elevated serum LDH was an independent risk factor for the prognosis of PQ poisoning patients (OR=9.95, 95%CI: 1.34-73.82, P=0.025). The area under the ROC curve of LDH was 0.811 (95%CI: 0.692-0.930). When the cut-off value was 340 U/L, the sensitivity was 0.889 and the specificity was 0.719. Log-rank test showed that there was a statistically significant difference in survival rate between the normal LDH group and the elevated LDH group (P=0.001) . Conclusion: Serum LDH has a good predictive value in evaluating the prognosis of patients with PQ poisoning. Elevated LDH is a risk factor for poor prognosis of patients with PQ poisoning.

Involvement of Mitochondrial Damage and Oxidative Stress in Apoptosis Induced by Betulin Plus Arsenic Trioxide in Neuroblastoma Cells

BACKGROUND/AIM

Arsenic trioxide (As₂O₃), a potent toxin in traditional Chinese medicine, has been utilized as an anticancer agent in Chinese culture for over a millennium. Betulin, commonly extracted from the bark of birch trees, has been identified for its pharmacological properties, including antibacterial, anti-inflammatory, antitumor, and antiviral activities. The aim of this study was to determine the efficacy and underlying anticancer signaling cascade induced by As₂O₃ and betulin in neuroblastoma cells.

MATERIALS AND METHODS

SK-N-SH cells were treated with As₂O₃ with or without betulin. Cell viability and apoptotic signaling were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, measurement of mitochondrial membrane potential (MMP) loss and reactive oxygen species (ROS), and quantitative western blotting analysis. Student's t-test in addition to one- or two-way analysis of variance was used to examine significant differences between comparison groups.

RESULTS

The combined treatment of As₂O₃ plus betulin was more effective than single treatments in suppressing cell viability and induction of apoptosis, which correlated well with elevated ROS levels. The apoptotic signaling cascade of As₂O₃ plus betulin was revealed as ROS elevation and relative loss of MMP, leading to the cleavage of caspase-3 and -9. As₂O₃ plus betulin treatment also reduced the expression of BCL2 apoptosis regulator, BH3-interacting domain death agonist, and BCL2-like-1.

CONCLUSION

The novel combination of As₂O₃ plus betulin has the potential to serve as a practical anti-neuroblastoma drug.

[Improvement of China's legal system for public health emergency management from the perspective of lifecycle management]

A crucial lesson gained through the pandemic preparedness and response to COVID-19 is that all measures for epidemic control must be law-based. The legal system is related not only to public health emergency management per se but also to all aspects of the institutional supporting system throughout the lifecycle. Based on the lifecycle emergency management model, this article analyses the problems of the current legal system and the potential solutions. It is suggested that the lifecycle emergency management model shall be followed to establish a more comprehensive public health legal system and to gather the intelligence and consensus of experts with different expertise, including epidemiologists, sociologists, economists, jurist and others, which will collaboratively promote the science-based legislation in the field of epidemic preparedness and response for the establishment of a comprehensive legal system for public health emergency management and with Chinese characteristics.

Therapeutic Applications of Mesenchymal Stem Cell Loaded with Gold Nanoparticles for Regenerative Medicine

In the present study, the various concentrations of AuNP (1.25, 2.5, 5, 10 ppm) were prepared to investigate the biocompatibility, biological performances and cell uptake efficiency via Wharton's jelly mesenchymal stem cells and rat model. The pure AuNP, AuNP combined with Col (AuNP-Col) and FITC conjugated AuNP-Col (AuNP-Col-FITC) were characterized by Ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR) and Dynamic Light Scattering (DLS) assays. For in vitro examinations, we explored whether the Wharton's jelly MSCs had better viability, higher CXCR4 expression, greater migration distance and lower apoptotic-related proteins expression with AuNP 1.25 and 2.5 ppm treatments. Furthermore, we considered whether the treatments of 1.25 and 2.5 ppm AuNP could induce the CXCR4 knocked down Wharton's jelly MSCs to express CXCR4 and reduce the expression level of apoptotic proteins. We also treated the Wharton's jelly MSCs with AuNP-Col to investigate the intracellular uptake mechanisms. The evidence demonstrated the cells uptake AuNP-Col through clathrin-mediated endocytosis and the vacuolar-type H⁺-ATPase pathway with good stability inside the cells to avoid lysosomal degradation as well as better uptake efficiency. Additionally, the results from in vivo examinations elucidated the 2.5 ppm of AuNP attenuated foreign body responses and had better retention efficacy with tissue integrity in animal model. In conclusion, the evidence demonstrates that AuNP shows promise as a biosafe nanodrug delivery system for development of regenerative medicine coupled with Wharton's jelly MSCs.

Association of Matrix Metalloproteinase-2 Genotypes With Prostate Cancer Risk

BACKGROUND/AIM

Prostate cancer is one of the most commonly diagnosed malignancies among males, especially in Western populations. Matrix metalloproteinase-2 (MMP-2) plays a critical role in extracellular regulation and metastasis. However, its genotypes have seldom been examined among patients with prostate cancer (PCa). Therefore, the purpose of the study was to evaluate the association of genotypes at MMP-2 promoter -1306 (rs243865) and -735 (rs2285053) with PCa risk in a Taiwanese cohort.

MATERIALS AND METHODS

The profiles of MMP-2 rs243865 and rs2285053 genotypes were examined among 218 PCa patients and 436 healthy controls by polymerase chain reaction-restriction fragment length polymorphism methodologies.

RESULTS

The percentages of wild-type CC, and variant CT and TT genotypes on MMP-2 rs243865 were 88.5, 10.6, and 0.9% in the PCa case group and 85.6, 13.5, and 0.9% in the control group, respectively (p for trend=0.5544). The allelic frequency distribution showed that the variant T allele at MMP-2 rs24386 5 was not associated with PCa risk (p=0.3250). As for MMP-2 rs2285053, the results were also non-significant. In addition, there was no association between the genotypes of MMP-2 rs243865 or rs2285053 with age or smoking status on PCa risk.

CONCLUSION

rs11568818 and rs11568819 at MMP-2 promoter region played minor roles in determining individual PCa risk.

The Contribution of Interleukin-8 Rs4073 Genotypes to Triple Negative Breast Cancer Risk in Taiwan

BACKGROUND/AIM

Triple negative breast cancer (TNBC) is one of the most challenging breast cancer types. Interleukin-8 (IL-8) is a pro-tumorigenic cytokine, promoting tumor proliferation and migration. This study aimed to examine the contribution of IL-8 rs4073 genotypes to breast cancer risk and provide a summary of related literature.

MATERIALS AND METHODS

IL-8 genotypic profiles were determined among 1,232 breast cancer cases and 1,232 controls via polymerase chain reaction-restriction fragment length polymorphism methodology.

RESULTS

The IL-8 rs4073 AT and AA genotypes had significantly lower prevalence in the case group compared to control group. Allelic frequency analysis showed that individuals carrying the A allele have relatively decreased risk for breast cancer. The stratification analysis showed that IL-8 rs4073 genotypes were protective markers for those with younger (≤55) age.

CONCLUSION

IL-8 rs4073 A allele is a novel predictor for breast cancer, especially TNBC.

Bioinformatics prediction of potential mechanisms and biomarkers underlying dilated cardiomyopathy

BACKGROUND

Heart failure is a health burden responsible for high morbidity and mortality worldwide, and dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. DCM is a disease of the heart muscle and is characterized by enlargement and dilation of at least one ventricle alongside impaired contractility with left ventricular ejection fraction < 40%. It is also associated with abnormalities in cytoskeletal proteins, mitochondrial ATP transporter, microvasculature, and fibrosis. However, the pathogenesis and potential biomarkers of DCM remain to be investigated.

AIM

To investigate the candidate genes and pathways involved in DCM patients.

METHODS

Two expression datasets (GSE3585 and GSE5406) were downloaded from the Gene Expression Omnibus database. The differentially expressed genes (DEGs) between the DCM patients and healthy individuals were identified using the R package "linear models for microarray data." The pathways with common DEGs were analyzed via Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene set enrichment analyses. Moreover, a protein-protein interaction network (PPI) was constructed to identify the hub genes and modules. The MicroRNA Database was applied to predict the microRNAs (miRNAs) targeting the hub genes. Additionally, immune cell infiltration in DCM was analyzed using CIBERSORT.

RESULTS

In total, 97 DEGs (47 upregulated and 50 downregulated) were identified. GO analysis showed that the DEGs were mainly enriched in "response to growth factor," "extracellular matrix," and "extracellular matrix structural constituent." KEGG pathway analysis indicated that the DEGs were mainly enriched in "protein digestion and absorption" and "interleukin 17 (IL-17) signaling pathway." The PPI network suggested that collagen type III alpha 1 chain (COL3A1) and COL1A2 contribute to the pathogenesis of DCM. Additionally, visualization of the interactions between miRNAs and the hub genes revealed that hsa-miR-5682 and hsa-miR-4500 interacted with both COL3A1 and COL1A2, and thus these miRNAs might play roles in DCM. Immune cell infiltration analysis revealed that DCM patients had more infiltrated plasma cells and fewer infiltrated B memory cells, T follicular helper cells, and resting dendritic cells.

CONCLUSION

COL1A2 and COL3A1 and their targeting miRNAs, hsa-miR-5682 and hsa-miR-4500, may play critical roles in the pathogenesis of DCM, which are closely related to the IL-17 signaling pathway and acute inflammatory response. These results may provide useful clues for the diagnosis and treatment of DCM.

A highly sensitive cell-based luciferase assay for high-throughput automated screening of SARS-CoV-2 nsp5/3CLpro inhibitors

Effective drugs against SARS-CoV-2 are urgently needed to treat severe cases of infection and for prophylactic use. The main viral protease (nsp5 or 3CLpro) represents an attractive and possibly broad-spectrum target for drug development as it is essential to the virus life cycle and highly conserved among betacoronaviruses. Sensitive and efficient high-throughput screening methods are key for drug discovery. Here we report the development of a gain-of-signal, highly sensitive cell-based luciferase assay to monitor SARS-CoV-2 nsp5 activity and show that it is suitable for high-throughput screening of compounds in a 384-well format. A benefit of miniaturisation and automation is that screening can be performed in parallel on a wild-type and a catalytically inactive nsp5, which improves the selectivity of the assay. We performed molecular docking-based screening on a set of 14,468 compounds from an in-house chemical database, selected 359 candidate nsp5 inhibitors and tested them experimentally. We identified four molecules, including the broad-spectrum antiviral merimepodib/VX-497, which show anti-nsp5 activity and inhibit SARS-CoV-2 replication in A549-ACE2 cells with IC 50 values in the 4-21 µM range. The here described assay will allow the screening of large-scale compound libraries for SARS-CoV-2 nsp5 inhibitors. Moreover, we provide evidence that this assay can be adapted to other coronaviruses and viruses which rely on a viral protease.

Double Superconducting Dome and Triple Enhancement of T_{c} in the Kagome Superconductor CsV_{3}Sb_{5} under High Pressure

CsV_{3}Sb_{5} is a newly discovered Z_{2} topological kagome metal showing the coexistence of a charge-density-wave (CDW)-like order at T^{*}=94  K and superconductivity (SC) at T_{c}=2.5  K at ambient pressure. Here, we study the interplay between CDW and SC in CsV_{3}Sb_{5} via measurements of resistivity, dc and ac magnetic susceptibility under various pressures up to 6.6 GPa. We find that the CDW transition decreases with pressure and experience a subtle modification at P_{c1}≈0.6-0.9  GPa before it vanishes completely at P_{c2}≈2  GPa. Correspondingly, T_{c}(P) displays an unusual M-shaped double dome with two maxima around P_{c1} and P_{c2}, respectively, leading to a tripled enhancement of T_{c} to about 8 K at 2 GPa. The obtained temperature-pressure phase diagram resembles those of unconventional superconductors, illustrating an intimated competition between CDW-like order and SC. The competition is found to be particularly strong for the intermediate pressure range P_{c1}≤P≤P_{c2} as evidenced by the broad superconducting transition and reduced superconducting volume fraction. The modification of CDW order around P_{c1} has been discussed based on the band structure calculations. This work not only demonstrates the potential to raise T_{c} of the V-based kagome superconductors, but also offers more insights into the rich physics related to the electron correlations in this novel family of topological kagome metals.

Contribution of Interleukin-10 Genotype to Triple Negative Breast Cancer Risk

BACKGROUND/AIM

Triple negative breast cancer (TNBC) is characterized by increased recurrence and poor survival. Mounting evidence suggests that interleukin-10 (IL-10) plays a role in carcinogenesis, however, little is known about the contribution of IL-10 to TNBC. The study evaluated the contribution of IL-10 promoter A-1082G (rs1800896), T-819C (rs3021097), A-592C (rs1800872) genotypes to the risk of TNBC.

MATERIALS AND METHODS

IL-10 genotypes were examined among 1,232 breast cancer patients and 1,232 controls and evaluated.

RESULTS

The percentages of AG and GG for IL-10 A-1082G genotypes were higher in the breast cancer patient group than in the control group. The GG genotype carriers were of higher risk for breast cancer [odds ratio (OR)=2.02, 95% confidence interval (CI)=1.28-3.21, p=0.0021]. Interestingly, G allele carriers were of higher risk of TNBC (OR=1.25, 95%CI=1.07-1.46, p=0.0050).

CONCLUSION

The G allele of IL-10 A-1082G genotype may serve as a predictor for TNBC risk. The finding should be validated in other populations.

[Analysis of integrated HCV surveillance in Shanghai, 2014-2019]

Objective: The purpose of this study is to analyze the surveillance data of the Integrated HCV surveillance in Shanghai and provide a scientific basis for HCV's elimination strategies. Methods: Descriptive statistical analysis and multivariate logistic regression analysis were performed using the multi-dimension results of the Integrated HCV surveillance in Shanghai from 2014 to 2019. Data related to reported HCV cases, HCV gene subtypes surveillance, HCV behavioral risk factors surveillance and HCV-antibody testing results of the community-based general population and high-risk/key populations. Results: The reported incidence rate of acute hepatitis C in Shanghai decreased from 2014 to 2019 (Z=-4.07, P<0.01); meanwhile, the reported incidence rate of chronic hepatitis C met an upward trend (Z=10.26,P<0.01), with an annual average, reported incidence rates of 0.18 per 100 000 and 8.60 per 100 000, respectively. Seven hundred forty-four blood samples were subtyped with 16 subtypes from 4 genotypes (GT1, GT2, GT3, and GT6). Among above, 1b (324 cases, 43.55%), 3a (121 cases, 16.26%), 3b (111 cases, 14.92%) and 6a (47 cases, 6.32%) were the principal subtypes. The composition of genotypes varied with decreased 1b and increased 3b and 6a. The major risk factors for HCV infection were blood transfusion (OR=4.18, 95%CI: 2.79-6.27), surgery (OR=1.63, 95%CI: 1.26-2.12), sharing syringe (OR=4.18, 95%CI: 2.75-6.34), pedicure (OR=2.01, 95%CI: 1.54-2.62), sharing razors (OR=4.09, 95%CI:1.24-13.51), and unsafe beauty practices (OR=3.15, 95%CI: 2.13-4.65). HCV antibody screening of 11 groups of high-risk/key populations showed that drug users had the highest HCV-antibody positive rate of 18.81% (1 008/5 358). The anti-HCV positive rate of the general population was 0.16% (7/4 268), which was significantly lower than that of high-risk/key populations from the same year, 2.50%(501/20 002) (χ²=94.04, P<0.01). Conclusions: Shanghai is a low-endemic area of HCV. Constantly carrying out integrated surveillance and analysis is of great value for early identification of HCV infected people and its risk factors, timely adjustment of prevention and control strategies, and eliminating the public health threat of HCV.

Sarcopenia as a Prognostic Factor for 90-Day and Overall Mortality in Patients Undergoing Spine Surgery for Metastatic Tumors: A Multicenter Retrospective Cohort Study

BACKGROUND

Novel methods in predicting survival in patients with spinal metastases may help guide clinical decision-making and stratify treatments regarding surgery vs palliative care.

OBJECTIVE

To evaluate whether the frailty/sarcopenia paradigm is predictive of survival and morbidity in patients undergoing surgery for spinal metastasis.

METHODS

A total of 271 patients from 4 tertiary care centers who had undergone surgery for spinal metastasis were identified. Frailty/sarcopenia was defined by psoas muscle size. Survival hazard ratios were calculated using multivariate analysis, with variables from demographic, functional, oncological, and surgical factors. Secondary outcomes included improvement of neurological function and postoperative morbidity.

RESULTS

Patients in the smallest psoas tertile had shorter overall survival compared to the middle and largest tertile. Psoas size (PS) predicted overall mortality more strongly than Tokuhashi score, Tomita score, and Karnofsky Performance Status (KPS). PS predicted 90-d mortality more strongly than Tokuhashi score, Tomita score, and KPS. Patients with a larger PS were more likely to have an improvement in deficit compared to the middle tertile. PS was not predictive of 30-d morbidity.

CONCLUSION

In patients undergoing surgery for spine metastases, PS as a surrogate for frailty/sarcopenia predicts 90-d and overall mortality, independent of demographic, functional, oncological, and surgical characteristics. The frailty/sarcopenia paradigm is a stronger predictor of survival at these time points than other standards. PS can be used in clinical decision-making to select which patients with metastatic spine tumors are appropriate surgical candidates.

Notch-Regulated Dendritic Cells Restrain Inflammation-Associated Colorectal Carcinogenesis

Conventional dendritic cells (cDC) play a central role in T-cell antitumor responses. We studied the significance of Notch-regulated DC immune responses in a mouse model of colitis-associated colorectal cancer in which there is epithelial downregulation of Notch/Hes1 signaling. This defect phenocopies that caused by GMDS (GDP-mannose 4,6-dehydratase) mutation in human colorectal cancers. We found that, although wild-type immune cells restrained dysplasia progression and decreased the incidence of adenocarcinoma in chimeric mice, the immune system with Notch2 deleted in all blood lineages or in only DCs promoted inflammation-associated transformation. Notch2 signaling deficiency not only impaired cDC terminal differentiation, but also downregulated CCR7 expression, reduced DC migration, and suppressed antigen cross-presentation to CD8⁺ T cells. Transfer of Notch-primed DCs restrained inflammation-associated dysplasia progression. Consistent with the mouse data, we observed a correlation between infiltrating cDC1 and Notch2 signaling in human colorectal cancers and found that GMDS-mutant colorectal cancers showed decreased CCR7 expression and suppressed cDC1 signature gene expression. Suppressed cDC1 gene signature expression in human colorectal cancer was associated with a poor prognosis. In summary, our study supports an important role for Notch2 signaling in cDC1-mediated antitumor immunity and indicates that Notch2-controlled DCs restrain inflammation-associated colon cancer development in mice.

Protective effects of valproic acid on 6-hydroxydopamine-induced neuroinjury

Oxidative stress may play critically important roles in the etiology of Parkinson's disease (PD). 6-Hydroxydopamine (6-OHDA) is a physiological neurotoxin reported to induce oxidative-induced apoptosis of dopaminergic neurons in PD mice models. Valproic acid (VPA), a clinical mood stabilizer, is a HDAC inhibitor with neuroprotective capacities. In the study, we aim at examining the feasibility of VPA as a protector for dopaminergic neurons against damage from 6-OHDA, and the intracellular mechanisms. The 6-OHDA-induced neurotoxicity to the human dopaminergic cell line SH-SY5Y was applied for examining VPA protective effects. Pretreatment with VPA was able to improve cell viability and reduce 6-OHDA-induced reactive oxygen species. Furthermore, a significant suppression of apoptotic caspases including cleaved caspase-3, caspase-7, and caspase-9 was observed. The results also revealed VPA decreased the 6-OHDA-induced Bax/Bcl2 ratio, as measured at protein level. These novel findings indicate that VPA may be capable of protecting the SH-SY5Y dopaminergic neuronal cells from 6-OHDA-induced toxicity via the deceasing of apoptotic caspases (cleaved caspase-3, caspase-7, and caspase-9) and reducing of the Bax/Bcl2 ratio. Very possibly, VPA could serve as not only a mood stabilizer but also a potential antidote for PD prevention.

Development of a precision medicine pipeline to identify personalized treatments for colorectal cancer

BACKGROUND

Metastatic colorectal cancer (CRC) continues to be a major health problem, and current treatments are primarily for disease control and palliation of symptoms. In this study, we developed a precision medicine strategy to discover novel therapeutics for patients with CRC.

METHODS

Six matched low-passage cell lines and patient-derived xenografts (PDX) were established from CRC patients undergoing resection of their cancer. High-throughput drug screens using a 119 FDA-approved oncology drug library were performed on these cell lines, which were then validated in vivo in matched PDXs. RNA-Seq analysis was then performed to identify predictors of response.

RESULTS

Our study revealed marked differences in response to standard-of-care agents across patients and pinpointed druggable pathways to treat CRC. Among these pathways co-targeting of fibroblast growth factor receptor (FGFR), SRC, platelet derived growth factor receptor (PDGFR), or vascular endothelial growth factor receptor (VEGFR) signaling was found to be an effective strategy. Molecular analyses revealed potential predictors of response to these druggable pathways.

CONCLUSIONS

Our data suggests that the use of matched low-passage cell lines and PDXs is a promising strategy to identify new therapies and pathways to treat metastatic CRC.

0337 Association Between Free-living Sleep and Memory and Attention in Healthy Adolescents

Introduction

Sleep is important for people of all ages, especially children during development. However, adolescents often sleep less than the recommended eight hours per night. Clinical trials have found that even partial sleep deprivation- shorter than the recommended duration- can reduce cognitive function in adolescents. The association between objectively measured free-living sleep and cognition function in adolescents has not been studied.

Methods

Free-living sleep duration and sleep efficiency were measured over one week with wrist actigraphy in 199 healthy normal adolescents (140 girls, mean±SD, 17.7±0.3 years). The day after the sleep measurement concluded, sustained attention was assessed with a validated Posner cue-target task, and working memory was measured with an n-back task. Associations between sleep measures and response times during attention and memory tasks were explored with multiple linear regression adjusted for task accuracy.

Results

Over the entire week, participants’ average sleep duration was 6.2±0.7 h/night and average sleep efficiency was 88±4.4% and averages for sleep the night prior to the cognitive testing were similar. Response times on memory (1-back: 420.6±73.9, 2-back: 522.6±101.9, and 3-back: 551.8±137.2 msec) and attention tasks (valid cue: 309±31.2, invalid cue: 365.8±36, and no cue: 393.6±38.9 msec) were similar to previous reports and not associated with average weekly sleep measures. Sleep duration of the night before cognitive testing was negatively associated with response times for the most challenging memory task (3-back; p=0.02). However, sleep measures of the night before did not correlate with any of the attention task scores.

Conclusion

Our data suggests that performance on difficult memory tasks may be negatively impacted by shorter free-living sleep durations the night prior to testing, even in healthy adolescents who average less than the recommended amount of sleep. Future studies should explore whether recovery sleep or other improvements in sleep habit might mitigate such effects on memory.

Support

The Eimskip University of Iceland Fund, Icelandic Centre for Research, National Institute of Diabetes and Digestive and Kidney Diseases.

Criterion for optimizing high-power acousto-optically Q-switched self-Raman yellow lasers with repetition rates up to 500 kHz

The criterion for optimizing the high-power acousto-optically ${Q}$Q-switched self-Raman yellow laser is originally explored for the repetition rate within 100-500 kHz. The minimum allowed value for the gate-open time is experimentally verified to be determined by the pulse buildup time. By using the minimum allowed gate-open time, the highest conversion efficiency can be achieved to raise the output power by approximately 20% in comparison with the conventional results. At a repetition rate of 200 kHz, the maximum output power at 588 nm can be up to 8.8 W at an incident pump power of 26 W. Furthermore, a practical formula is developed to accurately calculate the threshold pump power as a function of the gate-open time for a given repetition rate.

MESH1 is a cytosolic NADPH phosphatase that regulates ferroptosis

Critical to the bacterial stringent response is the rapid relocation of resources from proliferation toward stress survival through the respective accumulation and degradation of (p)ppGpp by RelA and SpoT homologues. While mammalian genomes encode MESH1, a homologue of the bacterial (p)ppGpp hydrolase SpoT, neither (p)ppGpp nor its synthetase has been identified in mammalian cells. Here, we show that human MESH1 is an efficient cytosolic NADPH phosphatase that facilitates ferroptosis. Visualization of the MESH1-NADPH crystal structure revealed a bona fide affinity for the NADPH substrate. Ferroptosis-inducing erastin or cystine deprivation elevates MESH1, whose overexpression depletes NADPH and sensitizes cells to ferroptosis, whereas MESH1 depletion promotes ferroptosis survival by sustaining the levels of NADPH and GSH and by reducing lipid peroxidation. The ferroptotic protection by MESH1 depletion is ablated by suppression of the cytosolic NAD(H) kinase, NADK, but not its mitochondrial counterpart NADK2. Collectively, these data shed light on the importance of cytosolic NADPH levels and their regulation under ferroptosis-inducing conditions in mammalian cells.

WHITE STRIPE LEAF8, encoding a deoxyribonucleoside kinase, is involved in chloroplast development in rice

WSL8 encoding a deoxyribonucleoside kinase (dNK) that catalyzes the first step in the salvage pathway of nucleotide synthesis plays an important role in early chloroplast development in rice. The chloroplast is an organelle that converts light energy into chemical energy; therefore, the normal differentiation and development of chloroplast are pivotal for plant survival. Deoxyribonucleoside kinases (dNKs) play an important role in the salvage pathway of nucleotides. However, the relationship between dNKs and chloroplast development remains elusive. Here, we identified a white stripe leaf 8 (wsl8) mutant that exhibited a white stripe leaf phenotype at seedling stage (before the four-leaf stage). The mutant showed a significantly lower chlorophyll content and defective chloroplast morphology, whereas higher reactive oxygen species than the wild type. As the leaf developed, the chlorotic mutant plants gradually turned green, accompanied by the restoration in chlorophyll accumulation and chloroplast ultrastructure. Map-based cloning revealed that WSL8 encodes a dNK on chromosome 5. Compared with the wild type, a C-to-G single base substitution occurred in the wsl8 mutant, which caused a missense mutation (Leu 349 Val) and significantly reduced dNK enzyme activity. A subcellular localization experiment showed the WSL8 protein was targeted in the chloroplast and its transcripts were expressed in various tissues, with more abundance in young leaves and nodes. Ribosome and RNA-sequencing analysis indicated that some components and genes related to ribosome biosynthesis were down-regulated in the mutant. An exogenous feeding experiment suggested that the WSL8 performed the enzymic activity of thymidine kinase, especially functioning in the salvage synthesis of thymidine monophosphate. Our results highlight that the salvage pathway mediated by the dNK is essential for early chloroplast development in rice.

Microbiota of Inflammatory Bowel Disease Models

Gut microbiome plays an important role in inflammatory bowel disease (IBD), a group of intestinal chronic inflammation conditions that affect a large population. The animal models of IBD have long been established on basis of pathological features, but their ability to recapitulate patient gut microbiota is unknown. We investigated and compared the composition and biodiversity of bacterial population in the fecal samples from rat models of the two IBD subtypes, and compared them with patient samples. Our analyses revealed that inflammation reduces overall microbiome diversity and increased variation between individuals. We identified specific microbial signatures associated with the two IBD subtypes that were consistent between the animal models and human IBD patients, suggesting that the animal models can partially recapitulate the microbiota in human diseases. Furthermore, metagenome prediction analysis suggested microbial functions that were likely altered by host-microbiota interactions in IBD models.

Single-Cell Transcriptomics Reveals Heterogeneity and Drug Response of Human Colorectal Cancer Organoids

Organoids are three-dimensional cell cultures that mimic organ functions and structures. The organoid model has been developed as a versatile in vitro platform for stem cell biology and diseases modeling. Tumor organoids are shown to share ~ 90% of genetic mutations with biopsies from same patients. However, it's not clear whether tumor organoids recapitulate the cellular heterogeneity observed in patient tumors. Here, we used single-cell RNA-Seq to investigate the transcriptomics of tumor organoids derived from human colorectal tumors, and applied machine learning methods to unbiasedly cluster subtypes in tumor organoids. Computational analysis reveals cancer heterogeneity sustained in tumor organoids, and the subtypes in organoids displayed high diversity. Furthermore, we treated the tumor organoids with a first-line cancer drug, Oxaliplatin, and investigated drug response in single-cell scale. Diversity of tumor cell populations in organoids were significantly perturbed by drug treatment. Single-cell analysis detected the depletion of chemosensitive subgroups and emergence of new drug tolerant subgroups after drug treatment. Our study suggests that the organoid model is capable of recapitulating clinical heterogeneity and its evolution in response to chemotherapy.

Effects of acarbose and siglitine on blood glucose fluctuation and islet β-cell function in patients with type 2 diabetes mellitus

The effects of acarbose and sitagliptin on blood glucose fluctuation and islet β-cell function in patients with type 2 diabetes mellitus (T2DM) were studied. One hundred and three patients with poorly controlled T2DM with insulin aspart 30 were selected and randomly divided into three groups: group A [continuous subcutaneous insulin infusion (CSII) treatment group], group B (CSII combined with acarbose treatment), group C (CSII combined with sitagliptin treatment). The treatment lasted for two weeks and the clinical indicators in the three groups were measured. The insulin dosage was adjusted according to the blood glucose statuses of the three groups of patients. In the final three days, 72 h of continuous glucose monitoring (CGM) were carried out, and the OGTT test was performed again. The results showed that the MODD (absolute means of daily difference), intra-day blood glucose fluctuation indices [(24 h MBG (mean blood glucose), LAGE (largest amplitude of glycemic excursions) and MAGE (average blood glucose fluctuation)] and postprandial blood glucose fluctuation indices [PGS (postprandial glucose spike), △t, PPGE (postprandial glucose excursion) and T (time) total] in group C and group B were significantly lower than those in group A. Compared with group B, the difference in blood glucose fluctuation indices in group C was not statistically significant (P>0.05). The HOMA-islet (homeostasis model assessment of islet) (CP-DM) index and FC-P (Fasting c-peptide) levels in group C and group B were significantly higher than those in group A (P less than 0.01). The HOMA-IR (CP) index of groups B and C was significantly lower than that of group A (P less than 0.01), and there was no statistically significant difference between groups B and C (P less than 0.05). Sitagliptin combined with intensive insulin pump therapy can reduce blood glucose fluctuation throughout the day, reduce insulin dosage, improve islet B cell function and reduce hypoglycemia better than intensive insulin pump therapy alone.

miR-34a is a microRNA safeguard for Citrobacter-induced inflammatory colon oncogenesis

Inflammation often induces regeneration to repair the tissue damage. However, chronic inflammation can transform temporary hyperplasia into a fertile ground for tumorigenesis. Here, we demonstrate that the microRNA miR-34a acts as a central safeguard to protect the inflammatory stem cell niche and reparative regeneration. Although playing little role in regular homeostasis, miR-34a deficiency leads to colon tumorigenesis after Citrobacter rodentium infection. miR-34a targets both immune and epithelial cells to restrain inflammation-induced stem cell proliferation. miR-34a targets Interleukin six receptor (IL-6R) and Interleukin 23 receptor (IL-23R) to suppress T helper 17 (Th17) cell differentiation and expansion, targets chemokine CCL22 to hinder Th17 cell recruitment to the colon epithelium, and targets an orphan receptor Interleukin 17 receptor D (IL-17RD) to inhibit IL-17-induced stem cell proliferation. Our study highlights the importance of microRNAs in protecting the stem cell niche during inflammation despite their lack of function in regular tissue homeostasis.

[Spatial-temporal distribution characteristics of hepatitis E in Shanghai, 2006-2016]

Objective: To understand the epidemiologic characteristics and spatial-temporal distribution of hepatitis E in Shanghai between 2006 and 2016. Methods: The reported incidence of hepatitis E and health facilities' information between 2006 and 2016 were collected from the China Information System for Disease Control and Prevention. The geographic information were from Shanghai Surveying and Mapping Institute. The map scale was 1∶750 000. Global and local autocorrelation, and spatial-temporal detection methods were applied to determine the spatial-temporal characteristics of hepatitis E. Software ArcGIS 10.1 was used to analyze global and local spatial auto correlation of hepatitis E spatial clusters. Software SaTScan 9.4.4 was used to conduct scan for exploring the areas of hepatitis E temporal spatial clusters. Results: A total of 6 048 cases of hepatitis E were reported in Shanghai during 2006-2016. The average incidence was 2.14/100 000. Spatial auto correlation analysis indicated that there was significant spatial positive correlations and spatial-temporal clustering of hepatitis E in Shanghai, and the "high-high cluster" was mainly located in the downtown of the city. Conclusion: Understanding the spatial-temporal clustering areas of hepatitis E cases in Shanghai from 2006 to 2016 is important to the reasonable allocation of public health resources and effective prevention and control of hepatitis E.

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.

Prometheus revisited

The liver's extraordinary ability to regenerate has been known since the myth of Prometheus, but the mechanisms involved are still being discovered. Various small animal models have been used in this quest. Two of the most popular include partial hepatectomy (PHx), in which two-thirds of the liver mass is surgically removed to evoke a massive, immediate stimulus for regeneration, and prolonged exposure to toxins that kill liver cells more gradually, provoking chronic regenerative activity. In either case, multiple types of cells must interact effectively to repopulate the organ with functional mature hepatocytes and thus assure ultimate restoration of healthy liver structure and function. This complexity has confounded efforts to distinguish specific changes that occur in cells that repopulate the hepatocyte compartment from changes in other cell populations, including subpopulations of hepatocytes or hepatocyte precursors that do not become regenerative. In the current issue of the JCI, Wang et al. used translating ribosome affinity purification followed by high-throughput RNA sequencing (TRAP-seq) to isolate mRNAs from repopulating hepatocytes in order to profile gene expression specifically in the hepatocytes that regenerate the liver following toxic injury imposed by inherent byproducts of tyrosine metabolism. This innovative methodology can potentially be used to design therapeutic strategies for liver regeneration.

[Impact on the incidence of postoperative ventricular arrhythmias after cardiac resynchronization therapy defibrillator with quadripolar lead]

Objective: To evaluate incidence of postoperative ventricular arrhythmias in patients who received cardiac resynchronization therapy defibrillator (CRT-D ) with left ventricular quadripolar lead. Methods: The patients received CRT-D who had complete follow-up data in Anhui Provincial Hospital from June 2013 to June 2016 were included and divided into quadripolar lead group and bipolar lead group according to the type of left ventricular lead. And ventricular arrhythmia (VA), implantable cardioverter-defibrillator (ICD) shocks treatment, antitachycardia pacing therapy (ATP), and other indicators of the two groups were compared. Prognosis of the two groups was assessed by re-hospitalization for heart failure and cardiac death. Results: Of the 220 patients enrolled in the study, 58 patients were in quadripolar lead group and 162 in bipolar lead group, and there were no significant differences in baseline characteristics between the two groups. The VA episode per patient was not significantly different between the two groups [(0.60±2.38) VA per person vs (0.93±2.24) VA per person, P=0.055]; the quadripolar lead group had significantly lower burden of VA compared with bipolar lead group [(0.22±0.91) per person-year vs (0.46±1.13) per person-year, P=0.044]. Compared with bipolar lead group, there were significant reduction in both the ICD shocks per patient and the burden of ICD shocks in quadripolar lead group: [(0.12±0.36) shocks per person vs (0.23±0.52) shocks per person, P=0.034] and [(0.04±0.17) per person-year vs (0.12±0.46) per person-year, P=0.029], respectively. There were no significant differences between the two groups in both the ATP per patient and the burden of ATP: [(1.07±3.77) ATP per person vs (1.26±3.01) ATP per person, P=0.073] and [(0.38±1.39) per person-year vs (0.63±1.48) per person-year, P=0.058], respectively. And there were no significant differences between the two groups for the survival (P=0.496). Conclusion: Compared with bipolar lead group, the burden of VA could be significantly reduced after CRT-D in the quadripolar lead group.

A Notch positive feedback in the intestinal stem cell niche is essential for stem cell self-renewal

The intestinal epithelium is the fastest regenerative tissue in the body, fueled by fast‐cycling stem cells. The number and identity of these dividing and migrating stem cells are maintained by a mosaic pattern at the base of the crypt. How the underlying regulatory scheme manages this dynamic stem cell niche is not entirely clear. We stimulated intestinal organoids with Notch ligands and inhibitors and discovered that intestinal stem cells employ a positive feedback mechanism via direct Notch binding to the second intron of the Notch1 gene. Inactivation of the positive feedback by CRISPR/Cas9 mutation of the binding sequence alters the mosaic stem cell niche pattern and hinders regeneration in organoids. Dynamical system analysis and agent‐based multiscale stochastic modeling suggest that the positive feedback enhances the robustness of Notch‐mediated niche patterning. This study highlights the importance of feedback mechanisms in spatiotemporal control of the stem cell niche.

Fucosylation Deficiency in Mice Leads to Colitis and Adenocarcinoma

BACKGROUND & AIMS

De novo synthesis of guanosine diphosphate (GDP)-fucose, a substrate for fucosylglycans, requires sequential reactions mediated by GDP-mannose 4,6-dehydratase (GMDS) and GDP-4-keto-6-deoxymannose 3,5-epimerase-4-reductase (FX or tissue specific transplantation antigen P35B [TSTA3]). GMDS deletions and mutations are found in 6%-13% of colorectal cancers; these mostly affect the ascending and transverse colon. We investigated whether a lack of fucosylation consequent to loss of GDP-fucose synthesis contributes to colon carcinogenesis.

METHODS

FX deficiency and GMDS deletion produce the same biochemical phenotype of GDP-fucose deficiency. We studied a mouse model of fucosylation deficiency (Fx-/- mice) and mice with the full-length Fx gene (controls). Mice were placed on standard chow or fucose-containing diet (equivalent to a control fucosylglycan phenotype). Colon tissues were collected and analyzed histologically or by enzyme-linked immunosorbent assays to measure cytokine levels; T cells also were collected and analyzed. Fecal samples were analyzed by 16s ribosomal RNA sequencing. Mucosal barrier function was measured by uptake of fluorescent dextran. We transplanted bone marrow cells from Fx-/- or control mice (Ly5.2) into irradiated 8-week-old Fx-/- or control mice (Ly5.1). We performed immunohistochemical analyses for expression of Notch and the hes family bHLH transcription factor (HES1) in colon tissues from mice and a panel of 60 human colorectal cancer specimens (27 left-sided, 33 right-sided).

RESULTS

Fx-/- mice developed colitis and serrated-like lesions. The intestinal pathology of Fx-/- mice was reversed by addition of fucose to the diet, which restored fucosylation via a salvage pathway. In the absence of fucosylation, dysplasia appeared and progressed to adenocarcinoma in up to 40% of mice, affecting mainly the right colon and cecum. Notch was not activated in Fx-/- mice fed standard chow, leading to decreased expression of its target Hes1. Fucosylation deficiency altered the composition of the fecal microbiota, reduced mucosal barrier function, and altered epithelial proliferation marked by Ki67. Fx-/- mice receiving control bone marrow cells had intestinal inflammation and dysplasia, and reduced expression of cytokines produced by cytotoxic T cells. Human sessile serrated adenomas and right-sided colorectal tumors with epigenetic loss of MutL homolog 1 (MLH1) had lost or had lower levels of HES1 than other colorectal tumor types or nontumor tissues.

CONCLUSIONS

In mice, fucosylation deficiency leads to colitis and adenocarcinoma, loss of Notch activation, and down-regulation of Hes1. HES1 loss correlates with the development of human right-sided colorectal tumors with epigenetic loss of MLH1. These findings indicate that carcinogenesis in a subset of colon cancer is consequent to a molecular mechanism driven by fucosylation deficiency and/or HES1-loss.

A miR-34a-Numb Feedforward Loop Triggered by Inflammation Regulates Asymmetric Stem Cell Division in Intestine and Colon Cancer

Emerging evidence suggests that microRNAs can initiate asymmetric division, but whether microRNA and protein cell fate determinants coordinate with each other remains unclear. Here, we show that miR-34a directly suppresses Numb in early-stage colon cancer stem cells (CCSCs), forming an incoherent feedforward loop (IFFL) targeting Notch to separate stem and non-stem cell fates robustly. Perturbation of the IFFL leads to a new intermediate cell population with plastic and ambiguous identity. Lgr5+ mouse intestinal/colon stem cells (ISCs) predominantly undergo symmetric division but turn on asymmetric division to curb the number of ISCs when proinflammatory response causes excessive proliferation. Deletion of miR-34a inhibits asymmetric division and exacerbates Lgr5+ ISC proliferation under such stress. Collectively, our data indicate that microRNA and protein cell fate determinants coordinate to enhance robustness of cell fate decision, and they provide a safeguard mechanism against stem cell proliferation induced by inflammation or oncogenic mutation.

Daily physical activity patterns from hip- and wrist-worn accelerometers

Accelerometer wear location may influence physical activity estimates. This study investigates this relationship through the examination of activity patterns throughout the day. Participants from the aging research evaluating accelerometry (AREA) study (n men  =  37, n women  =  47, mean age (SD)  =  78.9 (5.5) years) were asked to wear accelerometers in a free-living environment for 7 d at three different wear locations; one on each wrist and one on the right hip. During waking hours, wrist-worn accelerometers consistently produced higher median activity counts, about 5  ×  higher, as well as wider variability compared to hip-worn monitors. However, the shape of the accrual pattern curve over the course of the day for the hip and wrist are similar; there is a spike in activity in the morning, with a prolonged tapering of activity level as the day progresses. The similar patterns of hip and wrist activity accrual provide support that each location is capable of estimating total physical activity volume. The examination of activity patterns over time may provide a more detailed way to examine differences in wear location and different subpopulations.

Notch signalling regulates asymmetric division and inter-conversion between lgr5 and bmi1 expressing intestinal stem cells

Rapidly cycling LGR5+ intestinal stem cells (ISCs) located at the base of crypts are the primary driver of regeneration. Additionally, BMI1 expression is correlated with a slow cycling pool of ISCs located at +4 position. While previous reports have shown interconversion between these two populations following tissue injury, we provide evidence that NOTCH signaling regulates the balance between these two populations and promotes asymmetric division as a mechanism for interconversion in the mouse intestine. In both in vitro and in vivo models, NOTCH suppression reduces the ratio of BMI1+/LGR5+ ISCs while NOTCH stimulation increases this ratio. Furthermore, NOTCH signaling can activate asymmetric division after intestinal inflammation. Overall, these data provide insights into ISC plasticity, demonstrating a direct interconversion mechanism between slow- and fast-cycling ISCs.

NOTCH Signaling Regulates Asymmetric Cell Fate of Fast- and Slow-Cycling Colon Cancer-Initiating Cells

Colorectal cancer cells with stem-like properties, referred to as colon cancer-initiating cells (CCIC), have high tumorigenic potential. While CCIC can differentiate to promote cellular heterogeneity, it remains unclear whether CCIC within a tumor contain distinct subpopulations. Here, we describe the co-existence of fast- and slow-cycling CCIC, which can undergo asymmetric division to generate each other, highlighting CCIC plasticity and interconvertibility. Fast-cycling CCIC express markers, such as LGR5 and CD133, rely on MYC for their proliferation, whereas slow-cycling CCIC express markers, such as BMI1 and hTERT, are independent of MYC. NOTCH signaling promotes asymmetric cell fate, regulating the balance between these two populations. Overall, our results illuminate the basis for CCIC heterogeneity and plasticity by defining a direct interconversion mechanism between slow- and fast-cycling CCIC. Cancer Res; 76(11); 3411-21. ©2016 AACR.

Protective effect of penehyclidine hydrochloride on lipopolysaccharide-induced acute kidney injury in rat

We aimed to observe the effect of penehyclidine hydrochloride (PHC) on lipopolysaccharide (LPS)-induced acute kidney injury in rats and expression of tight junction proteins ZO-1 and occludin. Adult male Sprague-Dawley (SD) rats were divided randomly (N = 10) into control group (C), LPS group (LPS), low-dose PHC group (L-PHC), and high-dose PHC group (H-PHC). All rats, except C group, received a vena caudalis injection of 5.0 mg/kg LPS; after 30 min, rats in L-PHC and H-PHC groups received a vena caudalis injection of 0.3 and 0.9 mg/kg PHC. After 24 h, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, serum creatinine (Scr), and blood urea nitrogen (BUN) were detected. Histopathological changes and expression of ZO-1 and occludin were observed in renal tissues. Versus levels of TNF-α (38.5 ± 9.0), IL-1β (46.3 ± 12.7), Scr (37.2 ± 9.3), and BUN (6.5 ± 1.1) in control group, those in LPS group, TNF-α (159.0 ± 21.3), IL-1β (130.8 ± 18.7), Scr (98.5 ± 18.2), and BUN (12.8 ± 1.8), increased obviously (P < 0.05), with significantly structural changes and decreases of ZO-1 and occludin. However, TNF-α (111.3 ± 11.6), IL-1β (78.4 ± 14.3), Scr (51.3 ± 12.5), BUN (8.1 ± 1.2) in H-PHC group, and TNF-α (120.8 ± 14.3), IL-1β (92.5 ± 19.0), Scr (56.7 ± 14.7), BUN (9.7 ± 1.6) in L-PHC group were obviously decreased (P < 0.05). PHC has protective effects on acute kidney injury in sepsis, including abatement of renal tissue inflammation and functional improvement, potentially by upregulating ZO-1 and occludin.

miR-1269 promotes metastasis and forms a positive feedback loop with TGF-β

As patient survival drops precipitously from early-stage cancers to late-stage and metastatic cancers, microRNAs that promote relapse and metastasis can serve as prognostic and predictive markers as well as therapeutic targets for chemoprevention. Here we show that miR-1269a promotes colorectal cancer (CRC) metastasis and forms a positive feedback loop with TGF-β signalling. miR-1269a is upregulated in late-stage CRCs, and long-term monitoring of 100 stage II CRC patients revealed that miR-1269a expression in their surgically removed primary tumours is strongly associated with risk of CRC relapse and metastasis. Consistent with clinical observations, miR-1269a significantly increases the ability of CRC cells to invade and metastasize in vivo. TGF-β activates miR-1269 via Sox4, while miR-1269a enhances TGF-β signalling by targeting Smad7 and HOXD10, hence forming a positive feedback loop. Our findings suggest that miR-1269a is a potential marker to inform adjuvant chemotherapy decisions for CRC patients and a potential therapeutic target to deter metastasis.

A bio-inspired spatial patterning circuit

Lateral Inhibition (LI) is a widely conserved patterning mechanism in biological systems across species. Distinct from better-known Turing patterns, LI depend on cell-cell contact rather than diffusion. We built an in silico genetic circuit model to analyze the dynamic properties of LI. The model revealed that LI amplifies differences between neighboring cells to push them into opposite states, hence forming stable 2-D patterns. Inspired by this insight, we designed and implemented an electronic circuit that recapitulates LI patterning dynamics. This biomimetic system serve as a physical model to elucidate the design principle of generating robust patterning through spatial feedback, regardless of the underlying devices being biological or electrical.

Coexistence of neurofibroma and meningioma at exactly the same level of the cervical spine

We report a case of the coexistence of different spinal tumors at the same level of the cervical spine, without neurofibromatosis (NF), which was successfully treated with surgery. A 72-year-old female presented with right upper-limb clumsiness and weakness. Magnetic resonance imaging revealed an intradural, extramedullary tumor mass at the right C3-4 level with extradural extension into the intervertebral foramen. The extradural tumor was removed, and the pathology showed neurofibroma. After incision of the dura, the intradural tumor was removed, and was identified as meningioma in the pathological report. The patient did not meet the criteria of NF. Coexistence of neurofibroma and meningioma at exactly the same level of the spine without NF is extremely rare. Exploration of the intradural space may be necessary after resection of an extradural tumor if the surgical finding does not correlate well with the preoperative images.

A metabolic signature of colon cancer initiating cells

Colon cancer initiating cells (CCICs) are more tumorigenic and metastatic than the majority of colorectal cancer (CRC) cells. CCICs have also been associated with stem cell-like properties. However, there is a lack of system-level understanding of what mechanisms distinguish CCICs from common CRC cells. We compared the transcriptomes of CD133+ CCICs and CD133- CRC cells from multiple sources, which identified a distinct metabolic signature for CD133(high) CCICs. High-resolution unbiased metabolomics was then performed to validate this CCIC metabolic signature. Specifically, levels of enzymes and metabolites involved in glycolysis, the citric acid (TCA) cycle, and cysteine and methionine metabolism are altered in CCICs. Analyses of the alterations further suggest an epigenetic link. This metabolic signature provides mechanistic insights into CCIC phenotypes and may serve as potential biomarkers and therapeutic targets for future CRC treatment.

Randomized trial of nutrition education added to internet-based information and exercise at the work place for weight loss in a racially diverse population of overweight women

OBJECTIVE

Obesity in the United States is highly prevalent, approaching 60% for black women. We investigated whether nutrition education sessions at the work place added to internet-based wellness information and exercise resources would facilitate weight and fat mass loss in a racially diverse population of overweight female employees.

METHODS

A total of 199 (average body mass index 33.9±6.3 kg m(-2)) nondiabetic women (57% black) at our institution were randomized to a 6-month program of either internet-based wellness information (WI) combined with dietitian-led nutrition education group sessions (GS) weekly for 3 months and then monthly with shift in emphasis to weight loss maintenance (n=99) or to WI alone (n=100). All were given access to exercise rooms convenient to their work site. Fat mass was measured by dual-energy X-ray absorptiometry.

RESULTS

WI+GS subjects lost more weight than WI subjects at 3 months (-2.2±2.8 vs -1.0±3.0 kg, P>0.001). Weight (-2.7±3.9 vs -2.0±3.9 kg) and fat mass (-2.2±3.1 vs -1.7±3.7 kg) loss at 6 months was significant for WI+GS and WI groups (both P<0.001), but without significant difference between groups (both P>0.10); 27% of the WI+GS group achieved 5% loss of initial weight as did 18% of the WI group (P=0.180). Blacks and whites similarly completed the study (67 vs 74%, P=0.303), lost weight (-1.8±3.4 vs -3.3±5.2 kg, P=0.255) and fat mass (-1.6±2.7 vs -2.5±4.3 kg, P=0.532), and achieved 5% loss of initial weight (21 vs 32%, P=0.189), irrespective of group assignment.

CONCLUSION

Overweight women provided with internet-based wellness information and exercise resources at the work site lost weight and fat mass, with similar achievement by black and white women. Additional weight loss benefit of nutrition education sessions, apparent at 3 months, was lost by 6 months and may require special emphasis on subjects who fail to achieve weight loss goals to show continued value.

Fibroblast growth factor 21 (FGF21) and bone: is there a relationship in humans?

In animals, high fibroblast growth factor 21 (FGF21) states improve insulin resistance but induce bone loss. Whether FGF21 relates to bone mineral density (BMD) is unknown in humans. Contrary to prediction from animal findings, we found higher FGF21 levels associating with greater BMD in women, independent of age and body composition.

INTRODUCTION

Recent laboratory studies suggest that FGF21 is involved in reciprocal regulation of bone and energy homeostasis. Systemic administration of FGF21 protects animals from obesity and diabetes but causes severe bone loss, smothering the enthusiasm over FGF21 as a potential antiobesity therapeutic. To date, there is no information on whether FGF21 relates to BMD in humans. We thus studied the relationship between plasma FGF21 levels and BMD in healthy adults.

METHODS

Fasting plasma FGF21 levels were measured by enzyme-linked immunosorbent assay and body composition by dual-energy X-ray absorptiometry.

RESULTS

Among 40 healthy volunteers (age 32 ± 10 year, 16 women), men had significantly higher lean body mass (p < 0.01) and total BMD (p < 0.05), and lower percent body fat than women (p < 0.01). Median plasma FGF21 levels were not different between the sexes. While there was no association between FGF21 concentrations and body composition in men, FGF21 levels correlated positively with fat mass (p < 0.01) in women. In men, no significant correlation between FGF21 with BMD was observed. However, in women, FGF21 correlated positively with total BMD (R (2) = 0.69, p = 0.003) and spine BMD (R (2) = 0.76, p = 0.001); the correlation remained significant after adjusting for age, ethnicity, and body composition.

CONCLUSIONS

This study reveals for the first time a strong positive association between plasma FGF21 levels and BMD in healthy women, suggesting the association between bone loss and high FGF21 states in animals may not be directly translated to humans in physiologic states. We hypothesize that FGF21 may increase bone mass particularly in women through paracrine mechanisms in the bone-adipose interface.

Post-translational regulation enables robust p53 regulation

Background

The tumor suppressor protein p53 plays important roles in DNA damage repair, cell cycle arrest and apoptosis. Due to its critical functions, the level of p53 is tightly regulated by a negative feedback mechanism to increase its tolerance towards fluctuations and disturbances. Interestingly, the p53 level is controlled by post-translational regulation rather than transcriptional regulation in this feedback mechanism.

Results

We analyzed the dynamics of this feedback to understand whether post-translational regulation provides any advantages over transcriptional regulation in regard to disturbance rejection. When a disturbance happens, even though negative feedback reduces the steady-state error, it can cause a system to become less stable and transiently overshoots, which may erroneously trigger downstream reactions. Therefore, the system needs to balance the trade-off between steady-state and transient errors. Feedback control and adaptive estimation theories revealed that post-translational regulation achieves a better trade-off than transcriptional regulation, contributing to a more steady level of p53 under the influence of noise and disturbances. Furthermore, post-translational regulation enables cells to respond more promptly to stress conditions with consistent amplitude. However, for better disturbance rejection, the p53- Mdm2 negative feedback has to pay a price of higher stochastic noise.

Conclusions

Our analyses suggest that the p53-Mdm2 feedback favors regulatory mechanisms that provide the optimal trade-offs for dynamic control.