Background: Glycogen synthase kinase-3 (GSK-3) is a serine/threonine protein kinase, the activity of which is inhibited by a variety of extracellular stimuli including insulin, growth factors, cell ...specification factors and cell adhesion. Consequently, inhibition of GSK-3 activity has been proposed to play a role in the regulation of numerous signalling pathways that elicit pleiotropic cellular responses. This report describes the identification and characterisation of potent and selective small molecule inhibitors of GSK-3.
Results: SB-216763 and SB-415286 are structurally distinct maleimides that inhibit GSK-3α in vitro, with
K
is of 9 nM and 31 nM respectively, in an ATP competitive manner. These compounds inhibited GSK-3β with similar potency. However, neither compound significantly inhibited any member of a panel of 24 other protein kinases. Furthermore, treatment of cells with either compound stimulated responses characteristic of extracellular stimuli that are known to inhibit GSK-3 activity. Thus, SB-216763 and SB-415286 stimulated glycogen synthesis in human liver cells and induced expression of a β-catenin-LEF/TCF regulated reporter gene in HEK293 cells. In both cases, compound treatment was demonstrated to inhibit cellular GSK-3 activity as assessed by activation of glycogen synthase, which is a direct target of this kinase.
Conclusions: SB-216763 and SB-415286 are novel, potent and selective cell permeable inhibitors of GSK-3. Therefore, these compounds represent valuable pharmacological tools with which the role of GSK-3 in cellular signalling can be further elucidated. Furthermore, development of similar compounds may be of use therapeutically in disease states associated with elevated GSK-3 activity such as non-insulin dependent diabetes mellitus and neurodegenerative disease.
Short-acting β
2
-agonist bronchodilators are the most common medications used in treating chronic obstructive pulmonary disease (COPD). Genetic variants determining bronchodilator responsiveness ...(BDR) in COPD have not been identified.
We performed a genome-wide association study (GWAS) of BDR in 5789 current or former smokers with COPD in one African American and four white populations. BDR was defined as the quantitative spirometric response to inhaled β
2
-agonists. We combined results in a meta-analysis.
In the meta-analysis, SNPs in the genes
KCNK1
(P=2.02×10
−7
) and
KCNJ2
(P=1.79×10
−7
) were the top associations with BDR. Among African Americans, SNPs in
CDH13
were significantly associated with BDR (P=5.1×10
−9
). A nominal association with
CDH13
was identified in a gene-based analysis in all subjects.
We identified suggestive association with BDR among COPD subjects for variants near two potassium channel genes (
KCNK1
and
KCNJ2
). SNPs in
CDH13
were significantly associated with BDR in African Americans.
Endogenous small RNAs (endo-siRNAs) interact with Argonaute (AGO) proteins to mediate sequence-specific regulation of diverse biological processes. Here, we combine deep-sequencing and genetic ...approaches to explore the biogenesis and function of endo-siRNAs in C. elegans. We describe conditional alleles of the Dicer-related helicase, drh-3, that abrogate both RNA interference and the biogenesis of endo-siRNAs, called 22G-RNAs. DRH-3 is a core component of RNA-dependent RNA polymerase (RdRP) complexes essential for several distinct 22G-RNA systems. We show that, in the germline, one system is dependent on worm-specific AGOs, including WAGO-1, which localizes to germline nuage structures called P granules. WAGO-1 silences certain genes, transposons, pseudogenes, and cryptic loci. Finally, we demonstrate that components of the nonsense-mediated decay pathway function in at least one WAGO-mediated surveillance pathway. These findings broaden our understanding of the biogenesis and diversity of 22G-RNAs and suggest additional regulatory functions for small RNAs.
BACKGROUND: Because chronic obstructive pulmonary disease (COPD) is a heterogeneous condition, the identification of specific clinical phenotypes is key to developing more effective therapies. To ...explore if the persistence of systemic inflammation is associated with poor clinical outcomes in COPD we assessed patients recruited to the well-characterized ECLIPSE cohort (NCT00292552). METHODS AND FINDINGS: Six inflammatory biomarkers in peripheral blood (white blood cells (WBC) count and CRP, IL-6, IL-8, fibrinogen and TNF-α levels) were quantified in 1,755 COPD patients, 297 smokers with normal spirometry and 202 non-smoker controls that were followed-up for three years. We found that, at baseline, 30% of COPD patients did not show evidence of systemic inflammation whereas 16% had persistent systemic inflammation. Even though pulmonary abnormalities were similar in these two groups, persistently inflamed patients during follow-up had significantly increased all-cause mortality (13% vs. 2%, p<0.001) and exacerbation frequency (1.5 (1.5) vs. 0.9 (1.1) per year, p<0.001) compared to non-inflamed ones. As a descriptive study our results show associations but do not prove causality. Besides this, the inflammatory response is complex and we studied only a limited panel of biomarkers, albeit they are those investigated by the majority of previous studies and are often and easily measured in clinical practice. CONCLUSIONS: Overall, these results identify a novel systemic inflammatory COPD phenotype that may be the target of specific research and treatment.
Background
Low back pain (LBP) is the number one cause of disability worldwide; however, it is not clear how social determinants of health (SDOH) impact care management and outcomes related to ...physical therapy (PT) services for patients with LBP.
Objective
The purposes of this scoping review are to examine and assimilate the literature on how SDOH and PT care relate to non‐specific LBP outcomes and identify gaps in the literature to target for future research.
Methods
Data were extracted from eight electronic databases from January 2011 to February 2022. Reviewers independently screened all studies using the PRISMA extension for scoping review guidelines. Data related to study design, type of PT, type of non‐specific LBP, patient demographics, PT intervention, SDOH, and PT outcomes were extracted from the articles.
Results
A total of 30,523 studies were screened, with 1961 articles undergoing full text review. Ultimately, 76 articles were identified for inclusion. Sex and age were the most frequent SDOH examined (88% and 78% respectively) followed by education level (18%). Approximately half of the studies that examined age, sex, and education level identified no effect on outcomes. The number of studies examining other factors was small and the types of outcomes evaluated were variable, which limited the ability to pool results.
Conclusions
Sex and age were the most frequent SDOH examined followed by education level. Other factors were evaluated less frequently, making it difficult to draw conclusions. Study design and heterogeneity of determinants and outcomes were barriers to examining the potential impact on patients with LBP.
Polarity coordinates cell movement, differentiation, proliferation and apoptosis to build and maintain complex epithelial tissues such as the mammary gland. Loss of polarity and the deregulation of ...these processes are critical events in malignant progression but precisely how and at which stage polarity loss impacts on mammary development and tumourigenesis is unclear. Scrib is a core polarity regulator and tumour suppressor gene however to date our understanding of Scrib function in the mammary gland has been limited to cell culture and transplantation studies of cell lines. Utilizing a conditional mouse model of Scrib loss we report for the first time that Scrib is essential for mammary duct morphogenesis, mammary progenitor cell fate and maintenance, and we demonstrate a critical and specific role for Scribble in the control of the early steps of breast cancer progression. In particular, Scrib-deficiency significantly induced Fra1 expression and basal progenitor clonogenicity, which resulted in fully penetrant ductal hyperplasia characterized by high cell turnover, MAPK hyperactivity, frank polarity loss with mixing of apical and basolateral membrane constituents and expansion of atypical luminal cells. We also show for the first time a role for Scribble in mammalian spindle orientation with the onset of mammary hyperplasia being associated with aberrant luminal cell spindle orientation and a failure to apoptose during the final stage of duct tubulogenesis. Restoring MAPK/Fra1 to baseline levels prevented Scrib-hyperplasia, whereas persistent Scrib deficiency induced alveolar hyperplasia and increased the incidence, onset and grade of mammary tumours. These findings, based on a definitive genetic mouse model provide fundamental insights into mammary duct maturation and homeostasis and reveal that Scrib loss activates a MAPK/Fra1 pathway that alters mammary progenitor activity to drive premalignancy and accelerate tumour progression.
T cell exhaustion is an induced state of dysfunction that arises in response to chronic infection and cancer. Exhausted CD8
T cells acquire a distinct epigenetic state, but it is not known whether ...that chromatin landscape is fixed or plastic following the resolution of a chronic infection. Here we show that the epigenetic state of exhaustion is largely irreversible, even after curative therapy. Analysis of chromatin accessibility in HCV- and HIV-specific responses identifies a core epigenetic program of exhaustion in CD8
T cells, which undergoes only limited remodeling before and after resolution of infection. Moreover, canonical features of exhaustion, including super-enhancers near the genes TOX and HIF1A, remain 'epigenetically scarred.' T cell exhaustion is therefore a conserved epigenetic state that becomes fixed and persists independent of chronic antigen stimulation and inflammation. Therapeutic efforts to reverse T cell exhaustion may require new approaches that increase the epigenetic plasticity of exhausted T cells.
Emerin and lamin B receptor (LBR) are abundant transmembrane proteins of the nuclear envelope that are concentrated at the inner nuclear membrane (INM). Although both proteins interact with chromatin ...and nuclear lamins, they have distinctive biochemical and functional properties. Here, we have deployed proximity labeling using the engineered biotin ligase TurboID (TbID) and quantitative proteomics to compare the neighborhoods of emerin and LBR in cultured mouse embryonic fibroblasts. Our analysis revealed 232 high confidence proximity partners that interact selectively with emerin and/or LBR, 49 of which are shared by both. These included previously characterized NE-concentrated proteins, as well as a host of additional proteins not previously linked to emerin or LBR functions. Many of these are TM proteins of the ER, including two E3 ubiquitin ligases. Supporting these results, we found that 11/12 representative proximity relationships identified by TbID also were detected at the NE with the proximity ligation assay. Overall, this work presents methodology that may be used for large-scale mapping of the landscape of the INM and reveals a group of new proteins with potential functional connections to emerin and LBR.
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