scholarly journals Centromere Protein B Null Mice are Mitotically and Meiotically Normal but Have Lower Body and Testis Weights

1998 ◽  
Vol 141 (2) ◽  
pp. 309-319 ◽  
Author(s):  
Damien F. Hudson ◽  
Kerry J. Fowler ◽  
Elizabeth Earle ◽  
Richard Saffery ◽  
Paul Kalitsis ◽  
...  
Keyword(s):  
Cell Cycle Progression ◽  
Mammalian Species ◽  
Experimental Studies ◽  
Conflicting Evidence ◽  
Body Weights ◽  
Reduced Rate ◽  
And Function ◽  
Centromere Assembly ◽  
Mitosis And Meiosis

CENP-B is a constitutive centromere DNA-binding protein that is conserved in a number of mammalian species and in yeast. Despite this conservation, earlier cytological and indirect experimental studies have provided conflicting evidence concerning the role of this protein in mitosis. The requirement of this protein in meiosis has also not previously been described. To resolve these uncertainties, we used targeted disruption of the Cenpb gene in mouse to study the functional significance of this protein in mitosis and meiosis. Male and female Cenpb null mice have normal body weights at birth and at weaning, but these subsequently lag behind those of the heterozygous and wild-type animals. The weight and sperm content of the testes of Cenpb null mice are also significantly decreased. Otherwise, the animals appear developmentally and reproductively normal. Cytogenetic fluorescence-activated cell sorting and histological analyses of somatic and germline tissues revealed no abnormality. These results indicate that Cenpb is not essential for mitosis or meiosis, although the observed weight reduction raises the possibility that Cenpb deficiency may subtly affect some aspects of centromere assembly and function, and result in reduced rate of cell cycle progression, efficiency of microtubule capture, and/or chromosome movement. A model for a functional redundancy of this protein is presented.

scholarly journals Extracellular Vesicles and Thrombosis: Update on the Clinical and Experimental Evidence

2021 ◽  
Vol 22 (17) ◽  
pp. 9317
Author(s):  
Konstantinos Zifkos ◽  
Christophe Dubois ◽  
Katrin Schäfer
Keyword(s):  
Experimental Evidence ◽  
Extracellular Vesicles ◽  
Thrombus Formation ◽  
Experimental Studies ◽  
Cell Types ◽  
Heterogenous Group ◽  
Clearance Mechanism ◽  
And Function ◽  
Role And Function

Extracellular vesicles (EVs) compose a heterogenous group of membrane-derived particles, including exosomes, microvesicles and apoptotic bodies, which are released into the extracellular environment in response to proinflammatory or proapoptotic stimuli. From earlier studies suggesting that EV shedding constitutes a cellular clearance mechanism, it has become evident that EV formation, secretion and uptake represent important mechanisms of intercellular communication and exchange of a wide variety of molecules, with relevance in both physiological and pathological situations. The putative role of EVs in hemostasis and thrombosis is supported by clinical and experimental studies unraveling how these cell-derived structures affect clot formation (and resolution). From those studies, it has become clear that the prothrombotic effects of EVs are not restricted to the exposure of tissue factor (TF) and phosphatidylserines (PS), but also involve multiplication of procoagulant surfaces, cross-linking of different cellular players at the site of injury and transfer of activation signals to other cell types. Here, we summarize the existing and novel clinical and experimental evidence on the role and function of EVs during arterial and venous thrombus formation and how they may be used as biomarkers as well as therapeutic vectors.

Pentose Phosphate Pathway in Disease and Therapy

2014 ◽  
Vol 995 ◽  
pp. 1-27 ◽  
Author(s):  
Mahbuba Rahman ◽  
M. Rubayet Hasan
Keyword(s):  
Metabolic Pathways ◽  
Cell Cycle Progression ◽  
Metabolic Diseases ◽  
Pentose Phosphate ◽  
Cycle Progression ◽  
Novel Drugs ◽  
Abnormal Cells ◽  
Living Organisms ◽  
And Function

Pentose phosphate (PP) pathway, which is ubiquitously present in all living organisms, is one of the major metabolic pathways associated with glucose metabolism. The most important functions of this pathway includes the generation of reducing equivalents in the form of NADPH for reductive biosynthesis, and production of ribose sugars for the biosynthesis of nucleotides, amino acids, and other macromolecules required by all living cells. Under normal conditions of growth, PP pathway is important for cell cycle progression, myelin formation, and the maintenance of the structure and function of brain, liver, cortex and other organs. Under diseased conditions, such as in cases of many metabolic, neurological or malignant diseases, pathological mechanisms augment due to defects in the PP pathway genes. Adoption of alternative metabolic pathways by cells that are metabolically abnormal, or malignant cells that are resistant to chemotherapeutic drugs often plays important roles in disease progression and severity. Accordingly, the PP pathway has been suggested to play critical roles in protecting cancer or abnormal cells by providing reduced environment, to protect cells from oxidative damage and generating structural components for nucleic acids biosynthesis. Novel drugs that targets one or more components of the PP pathway could potentially serve to overcome challenges associated with currently available therapeutic options for many metabolic and non-metabolic diseases. However, careful designing of drugs is critical that takes into the accounts of cell’s broader genomic, proteomic and metabolic contexts under consideration, in order to avoid undesirable side-effects. In this review, we discuss the role of PP pathway under normal and abnormal physiological conditions and the potential of the PP pathway as a target for new drug development to treat metabolic and non-metabolic diseases.

New Insights about Regulatory T Cells Distribution and Function with Exercise: The Role of Immunometabolism

2020 ◽  
Vol 26 (9) ◽  
pp. 979-990 ◽  
Author(s):  
Gilson P. Dorneles ◽  
Aline A.Z. dos Passos ◽  
Pedro R.T. Romão ◽  
Alessandra Peres
Keyword(s):  
T Cells ◽  
Chronic Diseases ◽  
Experimental Studies ◽  
Treg Cells ◽  
Metabolic Phenotype ◽  
Acid Oxidation ◽  
Low Grade ◽  
And Function ◽  
Low Grade Inflammation

A lack of physical activity is linked to the development of many chronic diseases through a chronic low-grade inflammation state. It is now well accepted that the immune system plays a central role in the development of several chronic diseases, including insulin resistance, type 2 diabetes, atherosclerosis, heart failure and certain types of cancer. Exercise elicits a strong anti-inflammatory response independently of weight loss and can be a useful non-pharmacologic strategy to counteract the low-grade inflammation. The CD4+CD25+CD127- FoxP3+ Regulatory T (Treg) cells are a unique subset of helper T-cells, which regulate immune response and establish self-tolerance through the secretion of immunoregulatory cytokines, such as IL-10 and TGF-β, and the suppression of the function and activity of many immune effector cells (including monocytes/macrophages, dendritic cells, CD4+ and CD8+ T cells, and Natural Killers). The metabolic phenotype of Tregs are regulated by the transcription factor Foxp3, providing flexibility in fuel choice, but a preference for higher fatty acid oxidation. In this review, we focus on the mechanisms by which exercise - both acute and chronic - exerts its antiinflammatory effects through Treg cells mobilization. Furthermore, we discuss the implications of immunometabolic changes during exercise for the modulation of Treg phenotype and its immunosuppressive function. This narrative review focuses on the current knowledge regarding the role of Treg cells in the context of acute and chronic exercise using data from observational and experimental studies. Emerging evidence suggests that the immunomodulatory effects of exercise are mediated by the ability of exercise to adjust and improve Tregs number and function.

scholarly journals Perceived Threat of COVID-19 Influences Product Preferences: The Moderating Role of Consumers’ Mindset

2021 ◽  
Vol 29 (1) ◽  
pp. 78-86
Author(s):  
Felix Septianto ◽  
Tung Moi Chiew
Keyword(s):  
Affect Regulation ◽  
Experimental Studies ◽  
Perceived Threat ◽  
Conflicting Evidence ◽  
Regulation Strategies ◽  
Product Preferences ◽  
Self Protection ◽  
Moderating Role ◽  
Practical Implications

Recent research has suggested conflicting evidence on how consumers respond to threat (from diseases) concerning their product preferences. Specifically, consumers might exhibit higher versus lower preferences for typical (vs. atypical) products. Drawing upon the literature on consumption-based affect regulation and consumers’ mindset, this research seeks to reconcile these seemingly conflicting findings by establishing the moderating role of consumers’ mindset. In three experimental studies, we show that among consumers with a fixed (vs. growth) mindset, perceived threat of COVID-19 would lead to higher (vs. lower) preferences for typical products. Furthermore, these divergent effects are explained by two distinct affect regulation strategies. The effect of threat among consumers with a growth (vs. fixed) mindset will be mediated by regaining a sense of control (vs. self-protection). These findings contribute the literature on disease cues, affect regulation, and consumers’ mindset, and offer practical implications for marketers during COVID-19 pandemic.

scholarly journals Platelets as Modulators of Liver Diseases

2017 ◽  
Vol 44 (02) ◽  
pp. 114-125 ◽  
Author(s):  
James Luyendyk ◽  
Ton Lisman
Keyword(s):  
Liver Diseases ◽  
Clinical Evidence ◽  
Experimental Studies ◽  
Experimental Animal Models ◽  
Clinical Observations ◽  
Key Players ◽  
Thrombotic Complications ◽  
Injury And Repair ◽  
And Function

AbstractPlatelets are key players in thrombosis and hemostasis. Alterations in platelet count and function are common in liver disease, and may contribute to bleeding or thrombotic complications in liver diseases and during liver surgery. In addition to their hemostatic function, platelets may modulate liver diseases by mechanisms that are incompletely understood. Here, we present clinical evidence for a role of platelets in the progression of chronic and acute liver diseases, including cirrhosis, acute liver failure, and hepatocellular carcinoma. We also present clinical evidence that platelets promote liver regeneration following partial liver resection. Subsequently, we summarize studies in experimental animal models that support these clinical observations, and also highlight studies that are in contrast with clinical observations. The combined results of clinical and experimental studies suggest that platelets may be a therapeutic target in the treatment of liver injury and repair, but the gaps in our understanding of mechanisms involved in platelet-mediated modulation of liver diseases call for caution in clinical application of these findings.

scholarly journals Spinal cord microglia in health and disease

Acta Naturae ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 4-17
Author(s):  
Elena Kolos ◽  
Dmitry Korzhevsky
Keyword(s):  
Spinal Cord ◽  
Experimental Studies ◽  
Experimental Models ◽  
Specific Marker ◽  
Marker Proteins ◽  
Health And Disease ◽  
And Function ◽  
Lateral Sclerosis

The review summarizes data of recent experimental studies on spinal microglia, the least explored cells of the spinal cord. It focuses on the origin and function of microglia in mammalian spinal cord embryogenesis. The main approaches to the classification of microgliocytes based on their structure, function, and immunophenotypic characteristics are analyzed. We discuss the results of studies conducted on experimental models of spinal cord diseases such as multiple sclerosis, amyotrophic lateral sclerosis, systemic inflammation, and some others, with special emphasis on the key role of microglia in the pathogenesis of these diseases. The review highlights the need to detect the new microglia-specific marker proteins expressed at all stages of ontogeny. New sensitive and selective microglial markers are necessary in order to improve identification of spinal cord microgliocytes in normal and pathological conditions. Possible morphometric methods to assess the functional activity of microglial cells are presented.

scholarly journals Evaluating the Role of Wnt Signal Transduction in Promoting the Development of the Heart

2007 ◽  
Vol 7 ◽  
pp. 161-176 ◽  
Author(s):  
Leonard M. Eisenberg ◽  
Carol A. Eisenberg
Keyword(s):  
Signal Transduction ◽  
Planar Cell Polarity ◽  
Cardiac Development ◽  
Experimental Studies ◽  
Stem Cell Differentiation ◽  
Wnt Proteins ◽  
And Function ◽  
Canonical Wnt ◽  
Wnt Signal

Wnts are a family of secreted signaling proteins that are encoded by 19 distinct genes in the vertebrate genome. These molecules initiate several signal transduction pathways: the canonical Wnt, Wnt/Ca2+, and Wnt/planar cell polarity pathways. Wnt proteins have major impact on embryonic development, tumor progression, and stem cell differentiation. Wnt signal transduction also influences the formation of the heart, yet many issues concerning the involvement of Wnt regulation in initiating cardiac development remain unresolved. In this review, we will examine the published record to discern (a) what has been shown by experimental studies on the participation of Wnt signaling in cardiogenesis, and (b) what are the important questions that need to be addressed to understand the importance and function of Wnt signal transduction in facilitating the development of the heart.

scholarly journals The Changing Face of HDL and the Best Way to Measure It

2017 ◽  
Vol 63 (1) ◽  
pp. 196-210 ◽  
Author(s):  
Sotirios K Karathanasis ◽  
Lita A Freeman ◽  
Scott M Gordon ◽  
Alan T Remaley
Keyword(s):  
Cardiovascular Health ◽  
Experimental Studies ◽  
Hdl Cholesterol ◽  
Cholesterol Content ◽  
Epidemiologic Studies ◽  
Direct Role ◽  
Hdl Function ◽  
Lipid Biomarker ◽  
And Function

Abstract BACKGROUND HDL cholesterol (HDL-C) is a commonly used lipid biomarker for assessing cardiovascular health. While a central focus has been placed on the role of HDL in the reverse cholesterol transport (RCT) process, our appreciation for the other cardioprotective properties of HDL continues to expand with further investigation into the structure and function of HDL and its specific subfractions. The development of novel assays is empowering the research community to assess different aspects of HDL function, which at some point may evolve into new diagnostic tests. CONTENT This review discusses our current understanding of the formation and maturation of HDL particles via RCT, as well as the newly recognized roles of HDL outside RCT. The antioxidative, antiinflammatory, antiapoptotic, antithrombotic, antiinfective, and vasoprotective effects of HDL are all discussed, as are the related methodologies for assessing these different aspects of HDL function. We elaborate on the importance of protein and lipid composition of HDL in health and disease and highlight potential new diagnostic assays based on these parameters. SUMMARY Although multiple epidemiologic studies have confirmed that HDL-C is a strong negative risk marker for cardiovascular disease, several clinical and experimental studies have yielded inconsistent results on the direct role of HDL-C as an antiatherogenic factor. As of yet, our increased understanding of HDL biology has not been translated into successful new therapies, but will undoubtedly depend on the development of alternative ways for measuring HDL besides its cholesterol content.

scholarly journals Gcn5p Plays an Important Role in Centromere Kinetochore Function in Budding Yeast

2007 ◽  
Vol 28 (3) ◽  
pp. 988-996 ◽  
Author(s):  
Stefano Vernarecci ◽  
Prisca Ornaghi ◽  
AnaCristina Bâgu ◽  
Enrico Cundari ◽  
Paola Ballario ◽  
...  
Keyword(s):  
Cell Cycle Progression ◽  
Critical Role ◽  
Chromosome Loss ◽  
Cycle Progression ◽  
Kinetochore Assembly ◽  
Spindle Elongation ◽  
And Function ◽  
Insight Into ◽  
Kinetochore Function

ABSTRACT We report that the histone acetyltransferase Gcn5p is involved in cell cycle progression, whereas its absence induces several mitotic defects, including inefficient nuclear division, chromosome loss, delayed G2 progression, and spindle elongation. The fidelity of chromosome segregation is finely regulated by the close interplay between the centromere and the kinetochore, a protein complex hierarchically assembled in the centromeric DNA region, while disruption of GCN5 in mutants of inner components results in sick phenotype. These synthetic interactions involving the ADA complex lay the genetic basis for the critical role of Gcn5p in kinetochore assembly and function. We found that Gcn5p is, in fact, physically linked to the centromere, where it affects the structure of the variant centromeric nucleosome. Our findings offer a key insight into a Gcn5p-dependent epigenetic regulation at centromere/kinetochore in mitosis.

scholarly journals A methylation-phosphorylation switch determines Plk1 kinase activity and function in DNA damage repair

2019 ◽  
Vol 5 (3) ◽  
pp. eaau7566 ◽  
Author(s):  
Weizhe Li ◽  
Hong-Yan Wang ◽  
Xiaolu Zhao ◽  
Hongguo Duan ◽  
Binghua Cheng ◽  
...  
Keyword(s):  
Dna Damage ◽  
Cell Cycle Progression ◽  
Kinase Activity ◽  
Critical Role ◽  
Dna Damage Repair ◽  
Cycle Progression ◽  
Sister Chromatids ◽  
Damage Repair ◽  
And Function

Polo-like kinase 1 (Plk1) is a crucial regulator of cell cycle progression; but the mechanism of regulation of Plk1 activity is not well understood. We present evidence that Plk1 activity is controlled by a balanced methylation and phosphorylation switch. The methyltransferase G9a monomethylates Plk1 at Lys209, which antagonizes phosphorylation of T210 to inhibit Plk1 activity. We found that the methyl-deficient Plk1 mutant K209A affects DNA replication, whereas the methyl-mimetic Plk1 mutant K209M prolongs metaphase-to-anaphase duration through the inability of sister chromatids separation. We detected accumulation of Plk1 K209me1 when cells were challenged with DNA damage stresses. Ablation of K209me1 delays the timely removal of RPA2 and RAD51 from DNA damage sites, indicating the critical role of K209me1 in guiding the machinery of DNA damage repair. Thus, our study highlights the importance of a methylation-phosphorylation switch of Plk1 in determining its kinase activity and functioning in DNA damage repair.

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