A Mechanism Study on the Antioxidant Pathway of Keap1-Nrf2-ARE Inhibiting Ferroptosis in Dopaminergic Neurons.

BACKGROUND: The pathology of Parkinson's disease (PD) indicates that iron deposition exists in dopaminergic neurons, which may be related to the death of cellular lipid iron peroxide. The extracellular autophagy adaptor SQSTM1(p62) of dopamine (DA) neurons can activate the intracellular Keap1-Nrf2-ARE signaling pathway to inhibit ferroptosis, which has a protective effect on DA neurons. OBJECTIVE: The objective of this study was to investigate the protective mechanism of the Keap1-Nrf2-ARE antioxidant pathway against iron death in dopaminergic neurons. METHODS: The experiment was divided into a control group (Control group), 1-methyl-4-phenylpyridiniumion control group (MPP+ Control group), p62 overexpression group (MPP+OV-p62), and p62 overexpression no-load group (MPP+ OV-P62-NC). The inhibitors brusatol and ZnPP inhibited the activation of NF-E2-related factor 2(Nrf2) and Heme oxygenase-1(HO-1), respectively, and were divided into brusatol group (MPP+OV-p62+brusatol) and ZnPP group (MPP+OV-p62+ZnPP). RT-qPCR was used to detect transfection efficiency, and Cell Counting Kit-8 (CCK8) was used to detect cell activity. FerroOrange, 2,7-Dichlorodihydrofluorescein diacetate (DCFH-DA), and Liperfluo probes were used to detect intracellular iron, reactive oxygen species (ROS), and lipid peroxidation (LPO) levels. Western Blotting detected the levels of Nrf2, HO-1, Kelch-like ECH-associated protein1 (Keap1), and their downstream Glutathione peroxidase 4(GPX4) and Acyl-CoA synthetase long-chain family member 4(ACSL4). The levels of L-Glutathione (GSH) and Malondialdehyde (MDA) were detected by GSH and MDA kits, and the activation of Keap1-Nrf2-ARE pathway was verified at the cellular level to have an antioxidant protective effect on iron death in dopaminergic neurons. RESULTS: (1) The results of RT-qPCR showed that compared with the control group, the expression of the p62 gene was significantly increased in the MPP+OV-p62 groups (p = 0.039), and the p62 gene was significantly increased in the brusatol and ZnPP groups, indicating successful transfection (p =0.002; p=0.008). (2) The immunofluorescence probe flow results showed that compared to the normal control group, the contents of three kinds of probes in MPP+ model group were significantly increased (p =0.001; p <0.001; p<0.001), and the contents of three kinds of probes in MPP+OV-p62 group were decreased compared to the MPP+ model group (p =0.004). The results indicated that the levels of iron, ROS, and LPO were increased in the MPP+ group and decreased in the MPP+OV-p62 group. (3) Compared with the control group, the expressions of Nrf2, HO-1, and GPX4 in the MPP+OV-p62 group were increased (p =0.007; p =0.004; p=0.010), and the expressions of Keap1 and ACSL4 in MPP+p62 overexpression group were decreased (p =0.017; p =0.005). Compared with the MPP+ control group, Nrf2 and GPX4 were increased in the MPP+OV-p62 group, and ACSL4 was decreased in the MPP+OV-p62 group (p =0.041; p <0.001; p <0.001). The results of the GSH and MDA kit showed that compared with the normal control group, the content of GSH in the MPP+ control group was decreased (p < 0.01), and the content of MDA was increased (p < 0.01). Compared with the MPP+ model group, GSH content was increased (P = 0.003), and MDA content was decreased in the MPP+OV-p62 group (p < 0.001). Nrf2, HO-1, and GPX4 increased in the MPP+p62 overexpression group but decreased in the brusatol group and ZnPP group (p < 0.001). CONCLUSION: Based on the transfection of P62 plasmid, it was found that P62 plasmid can inhibit the lipid peroxidation of iron death in dopaminergic nerve cells by activating the Nrf2 signaling pathway, thus playing a protective role in dopaminergic nerve cells.

Geochemical behaviors of uranium and thorium during weathering and pedogenesis of carbonate rock: constraint from their speciation.

During weathering and pedogenesis of carbonate rock with poor-uranium (U) and thorium (Th), U and Th present the characteristics of strong leaching (especially U) and significant residual enrichment, the cause of which is still unclear. In this paper, a weathering profile developed by dolomite in karst area of Guizhou province in southwest China was selected, which showed zonation characteristics of bedrock (Y), powdery rock (Yf), and soil layer (T1 to T12) from the bottom to up. Through the determination of the occurrence speciation of U and Th in Y and weathering profile, combined with mineralogical, geochemical characteristics, and element mass balance calculation, the constraints of U and Th speciation on the geochemical behavior of U and Th during the weathering of carbonate rock were revealed. The results proved that U and Th in Y preferentially existed in acid insoluble phase, for example, the contents of U and Th in Y were 0.90 mg·kg-1 and 0.28 mg·kg-1, respectively, while those in acid insoluble matter were 2.34 mg·kg-1 and 2.57 mg·kg-1, respectively, but because the mass percentage of acid insoluble matter was extremely low (0.95%), the mass percentages of U and Th in the acid soluble phase in the whole rock were absolutely superior (96% of U and 86% Th). The U and Th in the acid soluble phase of Y were mainly adsorbed on the crystal surface of carbonate minerals or existed in the cement, and the U and Th in the carbonate lattice only accounted for a small proportion. From Y to Yf with the initial dissolution, U and Th released from the surface of carbonate minerals and cements were in carbonate-rich alkaline environment, and these portions of U and Th were leached out, resulting in strong loss of U and Th in the Yf (the loss rates are 83% of U and 65% of Th, respectively). From the Yf to the overlying soil layer T1, the carbonate components were completely dissolved, and the U and Th released from the carbonate lattice showed different behaviors, where U was completely leached and Th tended to stay in the weathered residue. Thus, in the soil layer T1 formed by Y or Yf , the residual U was the inheritance of the U in the acid insoluble phase of Y; For Th, it not only inherited the Th of acid insoluble phase of Y, but also superimposed the Th from carbonate lattice in Y. On the other hand, during the evolution process from Y to Yf and to soil layer T1, with the dissolution of carbonate, the acid insoluble phase also showed a significant tendency of chemical weathering. However, the U and Th in the Y acid insoluble phase were not leached with the decomposition of the acid insoluble phase but were redistributed among the residual phases. For the geochemical behaviors of U and Th in the evolution of soil profile (T1~T12), they were subjected to the occurrence speciation of U and Th in T1 and the change of U and Th occurrence speciation with the upward direction of soil profile. The U and Th released from the carrier minerals were mainly redistributed among the residual solid phases, which weakened the intensity of their further loss. This study deepens the understanding of the geochemical behavior of radionuclides in karst environment and provides reference for the treatment of radioactive pollution in karst areas.

Bioorthogonal Engineered Virus-Like Nanoparticles for Efficient Gene Therapy.

Gene therapy offers potentially transformative strategies for major human diseases. However, one of the key challenges in gene therapy is developing an effective strategy that could deliver genes into the specific tissue. Here, we report a novel virus-like nanoparticle, the bioorthgonal engineered virus-like recombinant biosome (reBiosome), for efficient gene therapies of cancer and inflammatory diseases. The mutant virus-like biosome (mBiosome) is first prepared by site-specific codon mutation for displaying 4-azido-L-phenylalanine on vesicular stomatitis virus glycoprotein of eBiosome at a rational site, and the reBiosome is then prepared by clicking weak acid-responsive hydrophilic polymer onto the mBiosome via bioorthogonal chemistry. The results show that the reBiosome exhibits reduced virus-like immunogenicity, prolonged blood circulation time and enhanced gene delivery efficiency to weakly acidic foci (like tumor and arthritic tissue). Furthermore, reBiosome demonstrates robust therapeutic efficacy in breast cancer and arthritis by delivering gene editing and silencing systems, respectively. In conclusion, this study develops a universal, safe and efficient platform for gene therapies for cancer and inflammatory diseases.

Socially Assistive Robots for People Living with Dementia in Long-Term Facilities: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND AND OBJECTIVE: The purpose of our study was to explore the immediate and long-term effects of socially assistive robots (SARs) on neuropsychiatric symptoms (NPSs), behavioral and psychological symptoms of dementia (BPSD), positive emotional experiences, and social interaction in older people living with dementia. METHODS: We set keywords and used Boolean operators to search the CINAHL, Cochrane Library, EMBASE, IEEE Digital Library, MEDLINE, PsycINFO, PubMed, Web of Science, Scopus, and Chinese Electronic Periodical Service from inception to February 2022 for randomized controlled trials. The Cochrane Collaboration bias assessment tool was used to assess article quality, and RevMan 5.4.1 software was used to conduct the meta-analysis. RESULTS: A total of 14 studies were included in the meta-analysis. SARs can help people living with dementia reduce their NPS of depression and anxiety, provide happiness from positive emotional experiences, and improve their social interaction through conversation. However, there was no significant improvement in agitation behavior, overall BPSD, or quality of life in people living with dementia. In follow-up, it was found that the effect of SRT was limited. CONCLUSION: SARs can reduce depression and increase positive emotions in people living with dementia. They may also reduce the burden on healthcare workers during the COVID-19 pandemic. This research was registered on PROSPERO CRD42020169340.

The effect of research on life satisfaction in middle-aged and older adults: physical disability and physical activity as a parallel and serial mediation analysis.

BACKGROUND AND OBJECTIVE: Maintaining the life satisfaction of frail middle-aged and older adults when they experience physical disability, lower activity status, or complex conditions that are related to each other is now an urgent issue. Therefore, the purpose of this study was to provide evidence for the impact of frailty in middle-aged and older adults on life satisfaction under the simultaneous occurrence and correlation of physical disability and physical activity status. METHODS: Data from the 2015 Taiwan Longitudinal Study in Ageing (TLSA) were analyzed by PROCESS in SPSS to explore three different mediation models (N = 4,421). The first was a parallel mediation model for exploring life satisfaction in middle-aged and older adults with frailty through physical disability or physical activity. The second was a serial mediation model for examining physical disability and physical activity in causal chains linked with a specific direction of flow and to test all combinations. The third was a moderated mediation model for testing whether the indirect effect of frailty status on life satisfaction through physical disability or physical activity was moderated by age stratification. RESULTS: Physical disability and physical activity partially mediated the relationship between frailty status and life satisfaction (IEOVERALL = -0.196, 95% CI: -0.255 to -0.139). The causal path with the highest indirect effect was found to be that between frailty and physical disability; increased frailty led to higher physical disability, which in turn affected physical activity, leading to lower life satisfaction (IE = 0.013, 95% CI: 0.008 to 0.019). The different stratifications by age significantly increased the mediating effect of physical activity (Index of Moderated Mediation = -0.107, SE = 0.052, 95% CI: -0.208 to -0.005) but did not reduce the mediating effect of physical disability. CONCLUSION: This study provides evidence that physical activity and physical disability influence the development of frailty. It also has a significant impact on the life satisfaction of middle-aged and older adults.

The Parallel Mediation Effects of Depression, Well-Being, and Social Activity on Physical Performance and Frailty in Community-Dwelling Middle-Aged and Older People.

Background: Frailty refers to a decline in an elderly person's physical, psychological, and social functioning, making them sensitive to stressors. Because frailty is caused by a variety of factors, including certain demographic characteristics, understanding the mediating factors that affect frailty in the elderly is critical. Purpose: To provide evidence about the relationship between depression, well-being, social activity, physical performance, and frailty among older adults. Materials and Methods: The study used secondary data from Taiwan's Long-term Study of Aging (n = 7,622), excluding people with severe dementia. The chi-square test and Spearmen's coefficient correlation were used to assess the relationship between the demographic variables and frailty. Nonparametric bootstrapping analysis was used to test whether depression, well-being, and social activity are parallel mediators of the relationship between physical performance and frailty. This study was approved by Fu Jen Catholic University (FJU-IRB No. C110040). Results: The overall frailty prevalence was 13.9%. We calculated a mean score and standard deviation for each measurement in this study. The correlation found low-to-moderate positive and negative statistically significant correlations between the variables. A significant, moderately negative relationship was found between physical performance and frailty that correlated with three potential mediating factors. The path indicated that lower physical performance scores and higher depression scores are more likely to be associated with frailty. Conclusion: Older adults who are depressed are more likely to become frail. Adults who are more socially active and report greater well-being are less likely to become frail. Therefore, further research should design and test a comprehensive intervention for older adults in community settings that addresses all three factors, aimed at increasing well-being and social activity while also treating depression.

Development and Assessment of the Validity and Reliability of the Short-Form Life Satisfaction Index (LSI-SF) among the Elderly Population.

BACKGROUND: Elderly care should focus on not only prolonging life but also satisfaction with elderly life. Our study investigated the reliability and validity of the Short-Form Life Satisfaction Index (LSI-SF). METHOD: Data were drawn from the 2015 Taiwan Longitudinal Study on Aging. Internal consistency reliability was used to confirm that the items measured the targeted characteristics. Construct validity was established by confirmatory factor analysis (CFA). Criterion-related validity was examined with the WHO-5 Well-Being Index as an indicator of quality of life. Known-group validity was determined from the difference between frailty stage and quality of life. RESULTS: The high consistency reliability supported the reliability of the LSI-SF. Rigorous CFA validated the construct validity of the LSI-SF. Perfect convergent and discriminant validity supported the validity of the LSI-SF. In addition, there was a significant correlation between the LSI-SF and the WHO-5 Well-Being Index. The LSI-SF appears to be a reliable measure of quality of life in the elderly. We found that frailty status was associated with lower life satisfaction, which supported the known-group validity. Life satisfaction was highest in the non-frailty stage and lowest in the frailty stage. CONCLUSIONS: The LSI-SF appears to be a valid and reliable measure of satisfaction with elderly life.

The Dose-Response Efficacy of Physical Training on Frailty Status and Physical Performance in Community-Dwelling Elderly: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

PURPOSE: This systematic review and meta-analysis was conducted to explore the effect of physical training on frailty status and physical performance in the community dwelling elderly. METHODS: We set keywords and used the Boolean operator to search the CEPS, CINAHL, Cochrane Library, PubMed, MEDLINE, and EMBASE databases from inception to 10 August 2021. The search was limited to randomized controlled trials (RCTs) conducted within a five-year period. The Cochrane Collaboration bias assessment tool was used to assess article quality, and RevMan 5.4.1. software (Cochrane Training site based in London, UK) was used to conduct the meta-analysis. RESULTS: Physical training was found to improve frailty status, physical performance, lower limb strength and balance. The best dose-response for physical training was 60 min per time, 2-3 times per week, for 3 months. CONCLUSION: Designing an appropriate physical training program can decrease the frailty score and increase physical performance in frail elderly in the community.

1,25-(OH)2D3 participates and modulates airway remodeling by reducing MGP and TGF-ß1 expression in TNF-α-induced airway smooth muscle cells.

BACKGROUND: Asthma has been proven to be a respiratory disorder that is characterized by the airway remodeling, airway inflammation and reversible airway obstruction. The 1,25-hydroxyvitamin D3 (1,25-(OH)2D3) plays critical roles in delaying remodeling. OBJECTIVES: To investigate the effects of 1,25-(OH)2D3 on the airway remodeling in tumor necrosis factor α (TNF-α)-induced airway smooth muscle cells (ASMCs). MATERIAL AND METHODS: The human ASMCs were divided into a blank control group (without treatment), a TNF-α group (treated with 10 ng/mL TNF-α) and a 1,25-(OH)2D3+TNF-α group (pre-treated with 10-7 M 1,25-(OH)2D3, then with 10 ng/mL TNF-α). The MTT assay was used to evaluate cell proliferation. Matrix Gla protein (MGP) and transforming growth factor ß1 (TGF-ß1) were examined using western blot assay. RESULTS: The TNF-α treatment significantly increased ASMCs proliferation and enhanced MGP and TGF-ß1 expression compared to a blank control group (p < 0.05). The 1,25-(OH)2D3 treatment (1,25-(OH)2D3+TNF-α group) significantly inhibited cell viability (0.83 ±0.01), compared to that in the TNF-α group (0.92 ±0.01) (p < 0.05). The 1,25-(OH)2D3 treatment significantly downregulated MGP expression (0.61 ±0.02), compared to that of the TNF-α group (1.51 ±0.35) (p < 0.05). The 1,25-(OH)2D3 treatment significantly reduced TGF-ß1 expression (0.69 ±0.17), compared to that of the TNF-α group (1.6 ±0.18) (p < 0.05). CONCLUSIONS: The 1,25-(OH)2D3 could participate and modulate airway remodeling by reducing MGP and TGF-ß1 expression in TNF-α-induced ASMCs. This study provided therapeutic insight and theoretical basis for clinical research.

Psychometric Properties of the Health Literacy Scale Used in the Taiwan Longitudinal Study on Middle-Aged and Older People.

Health literacy, an important factor in public and personal health, is regarded as the core of patient-centered care. Older people with high health literacy are more likely to maintain a healthier lifestyle, with good control and management of chronic diseases, than those lacking or with poor health literacy. Purpose: The present study investigated the validity and reliability of the Taiwan Longitudinal Study on Aging (TLSA) Health Literacy Scale. We also evaluated the health literacy of middle-aged and older Taiwanese adults, and its probable association with health outcomes and life satisfaction. Method: We analyzed the internal consistency reliability of the nine items of the 2015 TLSA Health Literacy Scale, and their relationship with the demographic variables. Brody Instrumental Activities of Daily Living (IADL) and the Life Satisfaction Index were used for criterion validity. Moreover, exploratory factor analysis was used to examine the construct validity and to test the known-group validity. Results: The TLSA health literacy scale has good internal consistency reliability. Criterion-related validity was supported by the fact that the health literacy score was significantly correlated with the IADL and Life Satisfaction Index. Factor analysis indicated a three-factor structure. Known-group validity was supported by the results, showing that middle-aged and older people with good self-reported health status had better health literacy. Conclusions: The TLSA health literacy scale is a reliable and valid instrument for measuring health literacy in middle-aged and older people.

Is high resolution a strict requirement for mass spectrometry-based cellular DNA adductomics?

Exposure to endogenous and exogenous factors can result in the formation of a wide variety of DNA adducts, and these may lead to gene mutations, thereby contributing to the development of cancer. DNA adductomics, a novel tool for exposomics, aims to detect the totality of DNA adducts. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) is the state-of-the-art method for DNA adductomic analysis, although its high cost has limited widespread use. In this study, we compared the analytical performance between HRMS and the more popular/accessible triple-quadrupole MS (QqQ-MS). We initially developed and optimized a hybrid quadrupole-linear ion trap-orbitrap MS (Q-LIT-OT-MS) method, considering the detection of both purine and pyrimidine adducts. LC-Q-LIT-OT-MS and LC-QqQ-MS methods were compared by non-targeted screening of formaldehyde-induced DNA adducts. Using the results from Q-LIT-OT-MS as the gold standard, QqQ-MS successfully detected 12 out of 18 formaldehyde-induced DNA adducts/inter-strand crosslinks (ICLs). QqQ-MS however also produced nine false-positive results owing to the inherent instrumental mass resolution limits. To discriminate the false-positive results from the accurate ones, we firstly introduced a statistical analysis, partial least squares-discriminant analysis, which efficiently excluded the false signals. Six DNA adducts/ICLs were not detected by QqQ-MS, due to insufficient sensitivity. This could be overcome by employing a selected reaction monitoring scan mode with multiple injections. Overall, this study demonstrated that high resolution may not be a strict requirement for MS-based DNA adductomics. LC-QqQ-MS with statistical analysis, could also provide a comparable performance as HRMS for pre-screening purposes.

Characterization and synthesis of indole-3-acetic acid in plant growth promoting Enterobacter sp.

Indole-3-acetic acid (IAA) plays an important role in the growth and development of plants. In this study, a series of predominant strains were isolated and identified as Enterobacter sp. with remarkable IAA-producing capabilities. The IAA-producing strains are mainly tryptophan-dependent and have significantly high yields of IAA (3477 µg mL-1 and 3378 µg mL-1). The ipdC gene encoding indole-3-pyruvate decarboxylase was identified by genomic analysis and RT-qPCR analysis, indicating the involvement of the indole-3-pyruvic acid (IPyA) pathway of IAA biosynthesis. The IPyA pathway was also confirmed by the intermediate assay. The IAA product of microbial metabolites was isolated, purified and characterized. These microbes exhibiting IAA production significantly promoted the growth of maize, increasing root length, plant height, fresh weight and dry weight. Thus, Enterobacter sp. with high IAA production has great prospects in agricultural and industrial applications.

A Study of Physical Activity, Frailty, and Health-Related Quality of Life Among Community-Dwelling Older Adults in Taiwan.

BACKGROUND: Health-related quality of life (HRQoL) in community-dwelling older adults increases as physical activity improves, and age-related frailty has a negative effect on HRQoL. Research on these associations is lacking. PURPOSE: The aims of this study were to (a) analyze the effect of demographic characteristics on HRQoL, (b) explore the correlation between physical activity and HRQoL, (c) analyze the effect of frailty on HRQoL, and (d) investigate the potential predictors of HRQoL in community-dwelling older adults. METHODS: In this cross-sectional study, a convenience sample of 150 older adults was recruited from community care sites in Shilin and Beitou Districts in Taipei City, Taiwan. Data were collected at baseline using a demographic characteristics datasheet, the Center for Epidemiologic Studies Depression Scale, the Physical Activity Scale for the Elderly, and the 12-Item Short Form Health Survey. The Senior Fitness Test and hand-grip strength test were also performed. Student t test, chi-square test, analysis of variance, Pearson correlation coefficient, and hierarchical regression were applied to analyze the statistical results using IBM SPSS Statistics Version 22.0. RESULTS: Being of older age, experiencing a higher number of falls, having more chronic diseases, and having a higher body mass index were identified as factors that significantly affect HRQoL. Moreover, HRQoL was found to be significantly affected by the performance of physical activity or status of frailty. Furthermore, the prefrail period was shown to be an important predictor of HRQoL after adjusting for demographic variables, history of chronic illness, history of falls, and physical activity. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: In this study, HRQoL was found to be significantly affected by upper limb dysfunction and the prefrail period. Community health promotion activities should focus greater attention on the physical functioning of older adults. Furthermore, providing information on age-related frailty and promoting active participation in community activities may increase the attention given by community-dwelling older adults to physical fitness and quality of life.

MAPbI3 Incorporated with Carboxyl Group Chelated Titania for Planar Perovskite Solar Cells in Low-Temperature Process.

Low-temperature, solution-processed, highly efficient hybrid organic/inorganic perovskite planar heterojunction solar cells were fabricated by incorporating reactive crystalline titania (h-TAc) into MAPbI3 layers. The h-TAc was prepared by the sol-gel reaction at low temperature followed by solvothermal treatment. The photoelectrical properties of the solar cells with h-TAc were analyzed. The incorporation with 0.85-wt% h-TAc showed the highest power conversion efficiency (PCE, 15.9%), increasing 69% compared to the pristine cell. The enhancement arose from large-grained microstructures, leading to a low rate of charge recombination. The carboxyl groups chelated on the surface of h-TAc revealed a strong attraction to lead ions, which are significantly helpful to MAPbI3 crystal growth.

KDM8/JMJD5 as a dual coactivator of AR and PKM2 integrates AR/EZH2 network and tumor metabolism in CRPC.

During the evolution into castration or therapy resistance, prostate cancer cells reprogram the androgen responses to cope with the diminishing level of androgens, and undergo metabolic adaption to the nutritionally deprived and hypoxia conditions. AR (androgen receptor) and PKM2 (pyruvate kinase M2) have key roles in these processes. We report in this study, KDM8/JMJD5, a histone lysine demethylase/dioxygnase, exhibits a novel property as a dual coactivator of AR and PKM2 and as such, it is a potent inducer of castration and therapy resistance. Previously, we showed that KDM8 is involved in the regulation of cell cycle and tumor metabolism in breast cancer cells. Its role in prostate cancer has not been explored. Here, we show that KDM8's oncogenic properties in prostate cancer come from its direct interaction (1) with AR to affect androgen response and (2) with PKM2 to regulate tumor metabolism. The interaction with AR leads to the elevated expression of androgen response genes in androgen-deprived conditions. They include ANCCA/ATAD2 and EZH2, which are directly targeted by KDM8 and involved in sustaining the survival of the cells under hormone-deprived conditions. Notably, in enzalutamide-resistant cells, the expressions of both KDM8 and EZH2 are further elevated, so are neuroendocrine markers. Consequently, EZH2 inhibitors or KDM8 knockdown both resensitize the cells toward enzalutamide. In the cytosol, KDM8 associates with PKM2, the gatekeeper of pyruvate flux and translocates PKM2 into the nucleus, where the KDM8/PKM2 complex serves as a coactivator of HIF-1α to upregulate glycolytic genes. Using shRNA knockdown, we validate KDM8's functions as a regulator for both androgen-responsive and metabolic genes. KDM8 thus presents itself as an ideal therapeutic target for metabolic adaptation and castration-resistance of prostate cancer cells.

A cullin 4B-RING E3 ligase complex fine-tunes pancreatic δ cell paracrine interactions.

Somatostatin secreted by pancreatic δ cells mediates important paracrine interactions in Langerhans islets, including maintenance of glucose metabolism through the control of reciprocal insulin and glucagon secretion. Disruption of this circuit contributes to the development of diabetes. However, the precise mechanisms that control somatostatin secretion from islets remain elusive. Here, we found that a super-complex comprising the cullin 4B-RING E3 ligase (CRL4B) and polycomb repressive complex 2 (PRC2) epigenetically regulates somatostatin secretion in islets. Constitutive ablation of CUL4B, the core component of the CRL4B-PRC2 complex, in δ cells impaired glucose tolerance and decreased insulin secretion through enhanced somatostatin release. Moreover, mechanistic studies showed that the CRL4B-PRC2 complex, under the control of the δ cell-specific transcription factor hematopoietically expressed homeobox (HHEX), determines the levels of intracellular calcium and cAMP through histone posttranslational modifications, thereby altering expression of the Cav1.2 calcium channel and adenylyl cyclase 6 (AC6) and modulating somatostatin secretion. In response to high glucose levels or urocortin 3 (UCN3) stimulation, increased expression of cullin 4B (CUL4B) and the PRC2 subunit histone-lysine N-methyltransferase EZH2 and reciprocal decreases in Cav1.2 and AC6 expression were found to regulate somatostatin secretion. Our results reveal an epigenetic regulatory mechanism of δ cell paracrine interactions in which CRL4B-PRC2 complexes, Cav1.2, and AC6 expression fine-tune somatostatin secretion and facilitate glucose homeostasis in pancreatic islets.

Identification and characterization of NPC1L1 variants in Uygur and Kazakh with extreme low-density lipoprotein cholesterol.

BACKGROUND: Plasma levels of low-density lipoprotein cholesterol (LDL-C) are a major risk factor for cardiovascular disease and are influenced by both heredity and dietary habits. The Niemann-Pick C1 like 1 (NPC1L1) protein mediates efficient dietary cholesterol absorption and contributes to variations in human LDL-C levels. METHODS: In the present study, using high throughput sequencing we identified three non-synonymous (NS) variations and 64 synonymous variations in the NPC1L1 gene from subsets of Chinese Han, Uygur and Kazakh populations with high or low LDL-C. Subsequently, three NS variations encoding R174H, V177I and V1284L substitutions were observed only in Uygur and Kazakh individuals with limited maximal plasma LDL-C levels. RESULTS: In further experiments, we investigated cholesterol-regulated recycling and glycosylation and stability of these NS NPC1L1 variants. However, no significant differences between WT and variant NPC1L1 proteins were observed using in vivo assays in mouse livers with adenovirus-mediated expression, demonstrating that none of the three NPC1L1 NS variants caused decreased uptake of biliary cholesterol. CONCLUSIONS: Simultaneously, these data indicate that R174H, V177I and V1284L NPC1L1 variations in high or low LDL-C individuals may not directly influence cholesterol absorption by NPC1L1.

Numb directs the subcellular localization of EAAT3 through binding the YxNxxF motif.

Excitatory amino acid transporter type 3 (EAAT3, also known as SLC1A1) is a high-affinity, Na(+)-dependent glutamate carrier that localizes primarily within the cell and at the apical plasma membrane. Although previous studies have reported proteins and sequence regions involved in EAAT3 trafficking, the detailed molecular mechanism by which EAAT3 is distributed to the correct location still remains elusive. Here, we identify that the YVNGGF sequence in the C-terminus of EAAT3 is responsible for its intracellular localization and apical sorting in rat hepatoma cells CRL1601 and Madin-Darby canine kidney (MDCK) cells, respectively. We further demonstrate that Numb, a clathrin adaptor protein, directly binds the YVNGGF motif and regulates the localization of EAAT3. Mutation of Y503, N505 and F508 within the YVNGGF motif to alanine residues or silencing Numb by use of small interfering RNA (siRNA) results in the aberrant localization of EAAT3. Moreover, both Numb and the YVNGGF motif mediate EAAT3 endocytosis in CRL1601 cells. In summary, our study suggests that Numb is a pivotal adaptor protein that mediates the subcellular localization of EAAT3 through binding the YxNxxF (where x stands for any amino acid) motif.

Prognostic Significance of CDCP1 Expression in Colorectal Cancer and Effect of Its Inhibition on Invasion and Migration.

BACKGROUND: To assess the correlations and functions of complement C1r/C1s, Uegf, Bmp1 domain-containing protein-1 (CDCP1) in identifying colorectal cancer (CRC) patients who are at high risk for metastasis. METHODS: Tumor specimens from 101 patients were analyzed by real-time polymerase chain reaction to detect CDCP1 expression. CDCP1 expression plasmids and shRNA were used to knock down CDCP1 expression in this study to investigate migratory and invasive abilities by Boyden chambers. The mRNA expression profiles in shCDCP1 transfectants were compared to those in control cells by conducting microarray analysis. Its downstream effectors were also invested in this study. RESULTS: CRC patients with a high CDCP1 expression had a statistically significant lower overall survival and disease-free survival compared to those exhibiting low CDCP1 expression. In vitro, knock-down CDCP1 expression significantly decreased migratory and invasive abilities in HCT116. Aberrant expression of CDCP1 increased cancer cell migration and invasion. By using integrated genomics, we identified ROCK1 (rho-associated, coiled-coil-containing protein kinase 1 pseudogene 1) as a downstream effector in CDCP1-mediated migration and as an invasion mediator. Clinically, ROCK1 and CDCP1 mRNA expression exhibited a strong positive correlation in CRC patient samples. CONCLUSIONS: Our results implicated CDCP1 as a key regulator of CRC migration and invasion, and suggest that it is a useful prognostic factor for patients with CRC. Improved identification of a high-risk subset of early metastatic patients may guide indications of individualized treatment in clinical practice.