scholarly journals Circadian Gene cry Controls Glioblastoma Tumorigenesis through Modulation of myc Expression

2021 ◽  
Author(s):  
Patricia Jarabo ◽  
Carmen de Pablo ◽  
Amanda González-Blanco ◽  
Sergio Casas-Tintó
Keyword(s):  
Premature Death ◽  
Pi3k Pathway ◽  
Heterogeneous Population ◽  
Circadian Gene ◽  
Drosophila Model ◽  
Great Relevance ◽  
Aggressive Tumor ◽  
Necessary And Sufficient ◽  
Tumoral Cells ◽  
The Brain

Glioblastoma (GB) is the most frequent malignant brain tumor among adults and currently there is no effective treatment. It is a very aggressive tumor that grows fast and spreads through the brain causing the death of patients in 15 months. GB cells mutate frequently and generate a heterogeneous population of tumoral cells genetically distinct. Thus, the contribution of genes and signaling pathways relevant for GB progression is of great relevance. We use a Drosophila model of GB that reproduces the features of human GB, and describe the upregulation of the circadian gene cry in GB patients and in a Drosophila GB model. We study the contribution of cry to the expansion of GB cells, to the neurodegeneration caused by GB, and to premature death and determine that cry is required for GB progression. Moreover, we analyze the mechanisms that regulate cry expression by the PI3K pathway. Finally, we conclude that cry is necessary and sufficient to regulate myc expression in GB. These results contribute to the understanding of the signals that impulse GB malignancy and lethality and open novel opportunities for the treatment of GB patients.

scholarly journals Glioma Revisited: From Neurogenesis and Cancer Stem Cells to the Epigenetic Regulation of the Niche

2012 ◽  
Vol 2012 ◽  
pp. 1-20 ◽  
Author(s):  
Felipe de Almeida Sassi ◽  
Algemir Lunardi Brunetto ◽  
Gilberto Schwartsmann ◽  
Rafael Roesler ◽  
Ana Lucia Abujamra
Keyword(s):  
Stem Cells ◽  
Cancer Stem Cells ◽  
Cellular Proliferation ◽  
Survival Rates ◽  
Comprehensive Analysis ◽  
Heterogeneous Population ◽  
Aggressive Tumor ◽  
Epigenetic Modulation ◽  
The Brain

Gliomas are the most incident brain tumor in adults. This malignancy has very low survival rates, even when combining radio- and chemotherapy. Among the gliomas, glioblastoma multiforme (GBM) is the most common and aggressive type, and patients frequently relapse or become refractory to conventional therapies. The fact that such an aggressive tumor can arise in such a carefully orchestrated organ, where cellular proliferation is barely needed to maintain its function, is a question that has intrigued scientists until very recently, when the discovery of the existence of proliferative cells in the brain overcame such challenges. Even so, the precise origin of gliomas still remains elusive. Thanks to new advents in molecular biology, researchers have been able to depict the first steps of glioma formation and to accumulate knowledge about how neural stem cells and its progenitors become gliomas. Indeed, GBM are composed of a very heterogeneous population of cells, which exhibit a plethora of tumorigenic properties, supporting the presence of cancer stem cells (CSCs) in these tumors. This paper provides a comprehensive analysis of how gliomas initiate and progress, taking into account the role of epigenetic modulation in the crosstalk of cancer cells with their environment.

scholarly journals Temporal gliosarcoma: case report and review of literature

2015 ◽  
Vol 22 (1) ◽  
pp. 112-116
Author(s):  
Amit Agrawal ◽  
Vissa Shanthi ◽  
Baddukonda Appala Ramakrishna ◽  
Kuppili Venkata Murali Mohan
Keyword(s):  
Case Report ◽  
Median Survival ◽  
Glial Cells ◽  
Primary Tumor ◽  
Clinical Presentation ◽  
Spindle Cell ◽  
Review Of Literature ◽  
Future Studies ◽  
Aggressive Tumor ◽  
The Brain

Abstract First characterized by Stroebe, the gliosarcomas are highly malignant and rare primary tumor of the brain composed of neoplastic glial cells in association with spindle cell sarcomatous elements (biphasic tissue patterns). In spite of being recognized as two different pathologies studies have not shown any significant differences between gliosarcoma and glioblastoma with regard to age, sex, size, clinical presentation, and median survival. In summary, gliosarcoma is an aggressive tumor with a propensity to recur and re-grow with poor outcome. Future studies are needed to understand the true pathology of these biphasic tumors.

scholarly journals News about the Role of Fluid and Imaging Biomarkers in Neurodegenerative Diseases

Biomedicines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 252
Author(s):  
Jacopo Meldolesi
Keyword(s):  
Neurodegenerative Diseases ◽  
Imaging Techniques ◽  
Imaging Biomarkers ◽  
Positron Emission ◽  
Specific Proteins ◽  
Great Relevance ◽  
The Brain ◽  
Positive Point

Biomarkers are molecules that are variable in their origin, nature, and mechanism of action; they are of great relevance in biology and also in medicine because of their specific connection with a single or several diseases. Biomarkers are of two types, which in some cases are operative with each other. Fluid biomarkers, started around 2000, are generated in fluid from specific proteins/peptides and miRNAs accumulated within two extracellular fluids, either the central spinal fluid or blood plasma. The switch of these proteins/peptides and miRNAs, from free to segregated within extracellular vesicles, has induced certain advantages including higher levels within fluids and lower operative expenses. Imaging biomarkers, started around 2004, are identified in vivo upon their binding by radiolabeled molecules subsequently revealed in the brain by positron emission tomography and/or other imaging techniques. A positive point for the latter approach is the quantitation of results, but expenses are much higher. At present, both types of biomarker are being extensively employed to study Alzheimer’s and other neurodegenerative diseases, investigated from the presymptomatic to mature stages. In conclusion, biomarkers have revolutionized scientific and medical research and practice. Diagnosis, which is often inadequate when based on medical criteria only, has been recently improved by the multiplicity and specificity of biomarkers. Analogous results have been obtained for prognosis. In contrast, improvement of therapy has been limited or fully absent, especially for Alzheimer’s in which progress has been inadequate. An urgent need at hand is therefore the progress of a new drug trial design together with patient management in clinical practice.

Article on Tay-Sachs Disease

2021 ◽  
pp. 475-478
Author(s):  
Bhawana. B. Bhende
Keyword(s):  
Autosomal Recessive ◽  
Genetic Disorder ◽  
Single Gene ◽  
Genetic Defect ◽  
Premature Death ◽  
Nerve Cells ◽  
Tay Sachs Disease ◽  
Hexosaminidase A ◽  
Physical Abilities ◽  
The Brain

Tay–Sachs disease is a genetic disorder that results in the destruction of nerve cells in the brain and spinal cord..also known as GM2 gangliosidosis or Hexosaminidase A deficiency) is an autosomal recessive genetic disorder. In its most common variant known as infantile Tay-Sachs disease it presents with a relentless deterioration of mental and physical abilities which commences at 6 months of age and usually results in death by the age of four.It is caused by a genetic defect in a single gene with one defective copy of that gene inherited from each parent. The disease occurs when harmful quantities of gangliosides accumulate in the nerve cells of the brain, eventually leading to the premature death of those cells. There is currently no cure or treatment. Tay- Sachs disease is a rare disease. Other autosomal disorders such as cystic fibrosis and sickle cell anemia are far more common. TSD is an autosomal recessive genetic disorder, meaning that when both parents are carriers, there is a 25% risk of giving birth to an affected child.

Steps toward recovery of function after hemilabyrinthectomy in frogs

1998 ◽  
Vol 119 (1) ◽  
pp. 27-33 ◽  
Author(s):  
Norbert Dieringer ◽  
Hans Straka
Keyword(s):  
Time Course ◽  
Recovery Of Function ◽  
Behavioral Deficits ◽  
Afferent Fibers ◽  
Vestibular Nuclear Complex ◽  
The Central Nervous System ◽  
Synaptic Changes ◽  
Necessary And Sufficient ◽  
The Brain

Removal of the labyrinthine organs on one side results in a number of severe postural and dynamic reflex deficits. Over time some of these behavioral deficits normalize again. At a chronic stage the brain of frogs exhibits a number of changes in vestibular and propriospinal circuits on the operated side that were studied in vitro. The onset of changes in the vestibular nuclear complex was delayed, became evident only after head posture had recovered by more than 50%, and was independent of the presence or absence of a degeneration of vestibular nerve afferent fibers. The time course of changes measured in the isolated spinal cord paralleled the time course of normalization of head and body posture. Results obtained after selective lesions of individual labyrinthine nerve branches show that unilateral inactivation of utricular afferent inputs is a necessary and sufficient condition to provoke postural deficits and propriospinal changes similar to those after the removal of all labyrinthine organs. The presence of multiple synaptic changes at distributed anatomic sites over different periods of time suggests that different parts of the central nervous system are involved in the normalization of different manifestations of the vestibular lesion syndrome. (Otolaryngol Head Neck Surg 1998;119:27–33.)

scholarly journals CCAP regulates feeding behavior via the NPF pathway in Drosophila adults

2020 ◽  
Vol 117 (13) ◽  
pp. 7401-7408 ◽  
Author(s):  
Michael J. Williams ◽  
Mehwish Akram ◽  
Deimante Barkauskaite ◽  
Sourabh Patil ◽  
Eirini Kotsidou ◽  
...  
Keyword(s):  
Feeding Behavior ◽  
The Other ◽  
Regulatory Role ◽  
Food Cues ◽  
Proboscis Extension Reflex ◽  
Increased Sensitivity ◽  
Proboscis Extension ◽  
Necessary And Sufficient ◽  
The Brain ◽  
Starvation Conditions

The intake of macronutrients is crucial for the fitness of any animal and is mainly regulated by peripheral signals to the brain. How the brain receives and translates these peripheral signals or how these interactions lead to changes in feeding behavior is not well-understood. We discovered that 2 crustacean cardioactive peptide (CCAP)-expressing neurons in Drosophila adults regulate feeding behavior and metabolism. Notably, loss of CCAP, or knocking down the CCAP receptor (CCAP-R) in 2 dorsal median neurons, inhibits the release of neuropeptide F (NPF), which regulates feeding behavior. Furthermore, under starvation conditions, flies normally have an increased sensitivity to sugar; however, loss of CCAP, or CCAP-R in 2 dorsal median NPF neurons, inhibited sugar sensitivity in satiated and starved flies. Separate from its regulation of NPF signaling, the CCAP peptide also regulates triglyceride levels. Additionally, genetic and optogenetic studies demonstrate that CCAP signaling is necessary and sufficient to stimulate a reflexive feeding behavior, the proboscis extension reflex (PER), elicited when external food cues are interpreted as palatable. Dopaminergic signaling was also sufficient to induce a PER. On the other hand, although necessary, NPF neurons were not able to induce a PER. These data illustrate that the CCAP peptide is a central regulator of feeding behavior and metabolism in adult flies, and that NPF neurons have an important regulatory role within this system.

scholarly journals Neurodegenerative disorders and sterile inflammation: lessons from a Drosophila model

2019 ◽  
Vol 166 (3) ◽  
pp. 213-221 ◽  
Author(s):  
Firzan Nainu ◽  
Emil Salim ◽  
Rangga Meidianto Asri ◽  
Aki Hori ◽  
Takayuki Kuraishi
Keyword(s):  
Neurodegenerative Diseases ◽  
Inflammatory Responses ◽  
Biological Significance ◽  
Sterile Inflammation ◽  
Medical Interventions ◽  
Drosophila Model ◽  
Progressive Neurodegeneration ◽  
Molecular Patterns ◽  
The Brain ◽  
Lateral Sclerosis

Abstract Central nervous system (CNS)-related disorders, including neurodegenerative diseases, are common but difficult to treat. As effective medical interventions are limited, those diseases will likely continue adversely affecting people’s health. There is evidence that the hyperactivation of innate immunity is a hallmark of most neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis and polyglutamine diseases. In mammalian and fly CNS, the presence of noninfectious ligands, including danger-associated molecular patterns, is recognized by (micro)glial cells, inducing the expression of proinflammatory cytokines. Such inflammation may contribute to the onset and progression of neurodegenerative states. Studies using fruit flies have shed light on the types of signals, receptors and cells responsible for inducing the inflammation that leads to neurodegeneration. Researchers are using fly models to assess the mechanisms of sterile inflammation in the brain and its link to progressive neurodegeneration. Given the similarity of its physiological system and biochemical function to those of mammals, especially in activating and regulating innate immune signalling, Drosophila can be a versatile model system for studying the mechanisms and biological significance of sterile inflammatory responses in the pathogenesis of neurodegenerative diseases. Such knowledge would greatly facilitate the quest for a novel effective treatment for neurodegenerative diseases.

scholarly journals X. A comparative study of the endocranial cast of Sinanthropus

1934 ◽  
Vol 223 (494-508) ◽  
pp. 469-487 ◽  
Keyword(s):  
Royal Society ◽  
Preliminary Report ◽  
Premature Death ◽  
Modern Human ◽  
Aboriginal Australians ◽  
Medical College ◽  
Human Brains ◽  
The Brain ◽  
Human Family ◽  
Human Fossils

We have made this attempt to describe and interpret the endocranial cast of Sinanthropus in deference to the wishes of Professor Davidson Black.* When he submitted to the Royal Society his preliminary report (Black, 1933, a ), he explained to us that he did not regard it as a disadvantage that his paper was incomplete, because it opened the way for those who had opportunities for comparing the cast with those of other human fossils and actual brains of primitive men and apes, to undertake the necessary work of comparison and interpretation, and we willingly undertake this duty. Each of us has independently studied the actual fossil skull in the Union Medical College at Peiping and examined the beautiful cast made by Professor Davidson Black from the actual fossils, and we should like to express our gratitude to him for these opportunities and many other kindnesses which he showed us. In studying the endocranial cast obtained from the Piltdown skull one of us (G.E.S.), years ago, was impressed by the extraordinary resemblance presented by the form of the brain in this extinct member of the human family to that of the primitive brain of a modern human being, a Sudanese negress (Elliot Smith, 1927, figs. 40 and 41). The other (J.L.S.) was impressed by the remarkable likeness to the endocranial cast of Sinanthropus of the brain of the Bushwoman, described in 1865 by Professor John Marshall. The recognition of these facts adds particular importance to the consideration that both the authors of this communication have served an apprenticeship to the task by examining large series of primitive brains, aboriginal Australians (J.L.S.) and Sudanese negroes (G.E.S.), and have devoted some attention to the comparison of the brains of the anthropoid apes and primitive men. In attempting to interpret the significance of the endocranial cast of Sinanthropus special attention must obviously be paid to comparison with the casts of Pithecanthropus and Eoanthropus . The comparison with the brains of the larger apes is also important, throwing light as it does upon the characters one ought to expect to find in extremely primitive human brains. In attempting to convey some real conception of the nature of the form of the brain we have resorted to the use of series of contours, figs. 10-14, so that the reader at a glance can obtain a graphic expression of the distinctive peculiarities of form. * The misfortune of his premature death deprives us of the pleasure of presenting this memoir to him.

scholarly journals Cocaine effects on mouse incentive-learning and human addiction are linked to α2 subunit-containing GABAA receptors

2010 ◽  
Vol 107 (5) ◽  
pp. 2289-2294 ◽  
Author(s):  
Claire I. Dixon ◽  
Hannah V. Morris ◽  
Gerome Breen ◽  
Sylvane Desrivieres ◽  
Sarah Jugurnauth ◽  
...  
Keyword(s):  
Behavioral Sensitization ◽  
Binding Pocket ◽  
Receptor Subtype ◽  
Medium Spiny Neurons ◽  
Gabaergic Neurotransmission ◽  
Spiny Neurons ◽  
Benzodiazepine Binding ◽  
Necessary And Sufficient ◽  
The Brain

Because GABAA receptors containing α2 subunits are highly represented in areas of the brain, such as nucleus accumbens (NAcc), frontal cortex, and amygdala, regions intimately involved in signaling motivation and reward, we hypothesized that manipulations of this receptor subtype would influence processing of rewards. Voltage-clamp recordings from NAcc medium spiny neurons of mice with α2 gene deletion showed reduced synaptic GABAA receptor-mediated responses. Behaviorally, the deletion abolished cocaine’s ability to potentiate behaviors conditioned to rewards (conditioned reinforcement), and to support behavioral sensitization. In mice with a point mutation in the benzodiazepine binding pocket of α2-GABAA receptors (α2H101R), GABAergic neurotransmission in medium spiny neurons was identical to that of WT (i.e., the mutation was silent), but importantly, receptor function was now facilitated by the atypical benzodiazepine Ro 15-4513 (ethyl 8-amido-5,6-dihydro-5-methyl-6-oxo-4H-imidazo [1,5-a] [1,4] benzodiazepine-3-carboxylate). In α2H101R, but not WT mice, Ro 15-4513 administered directly into the NAcc-stimulated locomotor activity, and when given systemically and repeatedly, induced behavioral sensitization. These data indicate that activation of α2−GABAA receptors (most likely in NAcc) is both necessary and sufficient for behavioral sensitization. Consistent with a role of these receptors in addiction, we found specific markers and haplotypes of the GABRA2 gene to be associated with human cocaine addiction.

scholarly journals IDENTIFICATION OF BRAIN SITES CONTROLLING FEMALE RECEPTIVITY IN MOSAICS OF DROSOPHILA MELANOGASTER

Genetics ◽  
1983 ◽  
Vol 103 (2) ◽  
pp. 179-195
Author(s):  
Laurie Tompkins ◽  
Jeffrey C Hall
Keyword(s):  
Drosophila Melanogaster ◽  
Minimum Amount ◽  
Male Courtship ◽  
Experimental Conditions ◽  
Female Receptivity ◽  
Female Genotype ◽  
Courtship Behaviors ◽  
Necessary And Sufficient ◽  
The Brain ◽  
Male Genotype

ABSTRACT We have identified cells in the brain of Drosophila melanogaster that are required to be of female genotype for receptivity to copulation with males. To do this, we determined experimental conditions in which female flies virtually always copulate, then measured the minimum amount of male courtship that is required to stimulate females to indicate their receptivity to copulation. We then observed gynandromorphs with female genitalia to determine whether the sex mosaics elicited at least the minimum amount of courtship and, if so, whether they copulated. By analyzing these gynandromorphs, in which the genotype of external and internal tissues could be ascertained, we were able to identify a group of cells in the dorsal anterior brain that, when bilaterally female, is necessary and sufficient for receptivity to copulation. This group of cells is anatomically distinct from those that are required to be of male genotype for the performance of courtship behaviors.

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