scholarly journals The missing link: does tunnelling nanotube-based supercellularity provide a new understanding of chronic and lifestyle diseases?

Open Biology ◽  
2016 ◽  
Vol 6 (6) ◽  
pp. 160057 ◽  
Author(s):  
Amin Rustom
Keyword(s):  
Neurodegenerative Disorders ◽  
Viral Infections ◽  
Current Knowledge ◽  
Stem Cell Differentiation ◽  
Stress Factors ◽  
Pathological State ◽  
Animal Cells ◽  
Cellular Mechanisms ◽  
Link Type ◽  
Field Of Vision

Tunnelling nanotubes (TNTs) are increasingly recognized as central players in a multitude of cellular mechanisms and diseases. Although their existence and functions in animal organisms are still elusive, emerging evidence suggests that they are involved in developmental processes, tissue regeneration, viral infections or pathogen transfer, stem cell differentiation, immune responses as well as initiation and progression of neurodegenerative disorders and cancer (see Sisakhtnezhad & Khosravi 2015 Eur. J. Cell Biol. 94, 429–443. ( doi:10.1016/j.ejcb.2015.06.010 )). A broader field of vision, including their striking functional and structural resemblance with nanotube-mediated phenomena found throughout the phylogenetic tree, from plants down to bacteria, points to a universal, conserved and tightly regulated mechanism of cellular assemblies. Based on our initial definition of TNTs as open-ended channels mediating membrane continuity between connected cells (Rustom et al. 2004 Science 303, 1007–1010. ( doi:10.1126/science.1093133 )), it is suggested that animal tissues represent supercellular assemblies that—besides opening discrete communication pathways—balance diverse stress factors caused by pathological changes or fluctuating physiological and environmental conditions, such as oxidative stress or nutrient shortage. By combining current knowledge about nanotube formation, intercellular transfer and communication phenomena as well as associated molecular pathways, a model evolves, predicting that the linkage between reactive oxygen species, TNT-based supercellularity and the intercellular shuttling of materials will have significant impact on diverse body functions, such as cell survival, redox/metabolic homeostasis and mitochondrial heteroplasmy. It implies that TNTs are intimately linked to the physiological and pathological state of animal cells and represent a central joint element of diverse diseases, such as neurodegenerative disorders, diabetes or cancer.

scholarly journals The Innate Antiviral Response in Animals: An Evolutionary Perspective from Flagellates to Humans

Viruses ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 758 ◽  
Author(s):  
Karim Majzoub ◽  
Florian Wrensch ◽  
Thomas F. Baumert
Keyword(s):  
Viral Infections ◽  
Current Knowledge ◽  
Innate Immune ◽  
Model Organisms ◽  
Animal Cells ◽  
Molecular Systems ◽  
Host Interactions ◽  
Animal Hosts ◽  
Immune Pathways ◽  
Innate Antiviral Response

Animal cells have evolved dedicated molecular systems for sensing and delivering a coordinated response to viral threats. Our understanding of these pathways is almost entirely defined by studies in humans or model organisms like mice, fruit flies and worms. However, new genomic and functional data from organisms such as sponges, anemones and mollusks are helping redefine our understanding of these immune systems and their evolution. In this review, we will discuss our current knowledge of the innate immune pathways involved in sensing, signaling and inducing genes to counter viral infections in vertebrate animals. We will then focus on some central conserved players of this response including Toll-like receptors (TLRs), RIG-I-like receptors (RLRs) and cGAS-STING, attempting to put their evolution into perspective. To conclude, we will reflect on the arms race that exists between viruses and their animal hosts, illustrated by the dynamic evolution and diversification of innate immune pathways. These concepts are not only important to understand virus-host interactions in general but may also be relevant for the development of novel curative approaches against human disease.

scholarly journals Cellular Mechanisms of Melatonin: Insight from Neurodegenerative Diseases

Biomolecules ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1158 ◽  
Author(s):  
Dongmei Chen ◽  
Tao Zhang ◽  
Tae Ho Lee
Keyword(s):  
Neurodegenerative Diseases ◽  
Neurodegenerative Disorders ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Cellular Mechanisms ◽  
Wide Range ◽  
Public Health Challenge ◽  
Cumulative Evidence ◽  
The Brain ◽  
Lateral Sclerosis

Neurodegenerative diseases are the second most common cause of death and characterized by progressive impairments in movement or mental functioning in the central or peripheral nervous system. The prevention of neurodegenerative disorders has become an emerging public health challenge for our society. Melatonin, a pineal hormone, has various physiological functions in the brain, including regulating circadian rhythms, clearing free radicals, inhibiting biomolecular oxidation, and suppressing neuroinflammation. Cumulative evidence indicates that melatonin has a wide range of neuroprotective roles by regulating pathophysiological mechanisms and signaling pathways. Moreover, melatonin levels are decreased in patients with neurodegenerative diseases. In this review, we summarize current knowledge on the regulation, molecular mechanisms and biological functions of melatonin in neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, vascular dementia and multiple sclerosis. We also discuss the clinical application of melatonin in neurodegenerative disorders. This information will lead to a better understanding of the regulation of melatonin in the brain and provide therapeutic options for the treatment of various neurodegenerative diseases.

scholarly journals The L1-dependant and Pol III transcribed Alu retrotransposon, from its discovery to innate immunity

2021 ◽  
Vol 48 (3) ◽  
pp. 2775-2789
Author(s):  
Ludwig Stenz
Keyword(s):  
Human Genome ◽  
Viral Infections ◽  
De Novo ◽  
Current Knowledge ◽  
Innate Immune ◽  
De Novo Mutation ◽  
Neuronal Diversity ◽  
Alu Sequences ◽  
Pol Iii ◽  
The Brain

AbstractThe 300 bp dimeric repeats digestible by AluI were discovered in 1979. Since then, Alu were involved in the most fundamental epigenetic mechanisms, namely reprogramming, pluripotency, imprinting and mosaicism. These Alu encode a family of retrotransposons transcribed by the RNA Pol III machinery, notably when the cytosines that constitute their sequences are de-methylated. Then, Alu hijack the functions of ORF2 encoded by another transposons named L1 during reverse transcription and integration into new sites. That mechanism functions as a complex genetic parasite able to copy-paste Alu sequences. Doing that, Alu have modified even the size of the human genome, as well as of other primate genomes, during 65 million years of co-evolution. Actually, one germline retro-transposition still occurs each 20 births. Thus, Alu continue to modify our human genome nowadays and were implicated in de novo mutation causing diseases including deletions, duplications and rearrangements. Most recently, retrotransposons were found to trigger neuronal diversity by inducing mosaicism in the brain. Finally, boosted during viral infections, Alu clearly interact with the innate immune system. The purpose of that review is to give a condensed overview of all these major findings that concern the fascinating physiology of Alu from their discovery up to the current knowledge.

scholarly journals Human Monocytes Plasticity in Neurodegeneration

Biomedicines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 717
Author(s):  
Ilenia Savinetti ◽  
Angela Papagna ◽  
Maria Foti
Keyword(s):  
Neurodegenerative Disorders ◽  
Current Knowledge ◽  
Neurological Diseases ◽  
Surface Marker ◽  
First Line ◽  
Surface Marker Expression ◽  
Physiological Properties ◽  
Attractive Therapeutic Target ◽  
The Brain ◽  
Lateral Sclerosis

Monocytes play a crucial role in immunity and tissue homeostasis. They constitute the first line of defense during the inflammatory process, playing a role in the pathogenesis and progression of diseases, making them an attractive therapeutic target. They are heterogeneous in morphology and surface marker expression, which suggest different molecular and physiological properties. Recent evidences have demonstrated their ability to enter the brain, and, as a consequence, their hypothetical role in different neurodegenerative diseases. In this review, we will discuss the current knowledge about the correlation between monocyte dysregulation in the brain and/or in the periphery and neurological diseases in humans. Here we will focus on the most common neurodegenerative disorders, such as Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis and multiple sclerosis.

scholarly journals Antimalarial drugs—are they beneficial in rheumatic and viral diseases?—considerations in COVID-19 pandemic

2021 ◽  
Author(s):  
Bogna Grygiel-Górniak
Keyword(s):  
Connective Tissue ◽  
Viral Infections ◽  
Current Knowledge ◽  
Inflammatory Diseases ◽  
Antiviral Drugs ◽  
In Vivo Studies ◽  
Viral Diseases ◽  
Cardiac Complications

AbstractThe majority of the medical fraternity is continuously involved in finding new therapeutic schemes, including antimalarial medications (AMDs), which can be useful in combating the 2019-nCoV: coronavirus disease (COVID-19). For many decades, AMDs have been widely used in the treatment of malaria and various other anti-inflammatory diseases, particularly to treat autoimmune disorders of the connective tissue. The review comprises in vitro and in vivo studies, original studies, clinical trials, and consensus reports for the analysis, which were available in medical databases (e.g., PubMed). This manuscript summarizes the current knowledge about chloroquine (CQ)/hydroxychloroquine (HCQ) and shows the difference between their use, activity, recommendation, doses, and adverse effects on two groups of patients: those with rheumatic and viral diseases (including COVID-19). In the case of connective tissue disorders, AMDs are prescribed for a prolonged duration in small doses, and their effect is observed after few weeks, whereas in the case of viral infections, they are prescribed in larger doses for a short duration to achieve a quick saturation effect. In rheumatic diseases, AMDs are well tolerated, and their side effects are rare. However, in some viral diseases, the effect of AMDs is questionable or not so noticeable as suggested during the initial prognosis. They are mainly used as an additive therapy to antiviral drugs, but recent studies have shown that AMDs can diminish the efficacy of some antiviral drugs and may cause respiratory, kidney, liver, and cardiac complications.

scholarly journals Antioxidant and Signaling Role of Plastid-Derived Isoprenoid Quinones and Chromanols

2021 ◽  
Vol 22 (6) ◽  
pp. 2950
Author(s):  
Beatrycze Nowicka ◽  
Agnieszka Trela-Makowej ◽  
Dariusz Latowski ◽  
Kazimierz Strzalka ◽  
Renata Szymańska
Keyword(s):  
Current Knowledge ◽  
Stress Factors ◽  
Oxygenic Photosynthesis ◽  
Ros Generation ◽  
Main Site ◽  
Storage Lipids ◽  
Abiotic Stress Factors ◽  
Cell Components ◽  
And Function

Plant prenyllipids, especially isoprenoid chromanols and quinols, are very efficient low-molecular-weight lipophilic antioxidants, protecting membranes and storage lipids from reactive oxygen species (ROS). ROS are byproducts of aerobic metabolism that can damage cell components, they are also known to play a role in signaling. Plants are particularly prone to oxidative damage because oxygenic photosynthesis results in O2 formation in their green tissues. In addition, the photosynthetic electron transfer chain is an important source of ROS. Therefore, chloroplasts are the main site of ROS generation in plant cells during the light reactions of photosynthesis, and plastidic antioxidants are crucial to prevent oxidative stress, which occurs when plants are exposed to various types of stress factors, both biotic and abiotic. The increase in antioxidant content during stress acclimation is a common phenomenon. In the present review, we describe the mechanisms of ROS (singlet oxygen, superoxide, hydrogen peroxide and hydroxyl radical) production in chloroplasts in general and during exposure to abiotic stress factors, such as high light, low temperature, drought and salinity. We highlight the dual role of their presence: negative (i.e., lipid peroxidation, pigment and protein oxidation) and positive (i.e., contribution in redox-based physiological processes). Then we provide a summary of current knowledge concerning plastidic prenyllipid antioxidants belonging to isoprenoid chromanols and quinols, as well as their structure, occurrence, biosynthesis and function both in ROS detoxification and signaling.

scholarly journals Curcuma Longa, the “Golden Spice” to Counteract Neuroinflammaging and Cognitive Decline—What Have We Learned and What Needs to Be Done

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1519
Author(s):  
Alessandra Berry ◽  
Barbara Collacchi ◽  
Roberta Masella ◽  
Rosaria Varì ◽  
Francesca Cirulli
Keyword(s):  
Molecular Structure ◽  
Cognitive Decline ◽  
Neurodegenerative Disorders ◽  
Natural Compound ◽  
Water Solubility ◽  
Current Knowledge ◽  
Curcuma Longa ◽  
Biomedical Literature ◽  
Global Increase ◽  
New Strategies

Due to the global increase in lifespan, the proportion of people showing cognitive impairment is expected to grow exponentially. As target-specific drugs capable of tackling dementia are lagging behind, the focus of preclinical and clinical research has recently shifted towards natural products. Curcumin, one of the best investigated botanical constituents in the biomedical literature, has been receiving increased interest due to its unique molecular structure, which targets inflammatory and antioxidant pathways. These pathways have been shown to be critical for neurodegenerative disorders such as Alzheimer’s disease and more in general for cognitive decline. Despite the substantial preclinical literature on the potential biomedical effects of curcumin, its relatively low bioavailability, poor water solubility and rapid metabolism/excretion have hampered clinical trials, resulting in mixed and inconclusive findings. In this review, we highlight current knowledge on the potential effects of this natural compound on cognition. Furthermore, we focus on new strategies to overcome current limitations in its use and improve its efficacy, with attention also on gender-driven differences.

scholarly journals Dual-Specificity, Tyrosine Phosphorylation-Regulated Kinases (DYRKs) and cdc2-Like Kinases (CLKs) in Human Disease, an Overview

2021 ◽  
Vol 22 (11) ◽  
pp. 6047
Author(s):  
Mattias F. Lindberg ◽  
Laurent Meijer
Keyword(s):  
Tyrosine Phosphorylation ◽  
Human Disease ◽  
Intracellular Signaling ◽  
Neuronal Development ◽  
Viral Infections ◽  
Current Knowledge ◽  
Lymphoblastic Leukemia ◽  
Cell Cycle Control ◽  
Megakaryoblastic Leukemia ◽  
Dual Specificity

Dual-specificity tyrosine phosphorylation-regulated kinases (DYRK1A, 1B, 2-4) and cdc2-like kinases (CLK1-4) belong to the CMGC group of serine/threonine kinases. These protein kinases are involved in multiple cellular functions, including intracellular signaling, mRNA splicing, chromatin transcription, DNA damage repair, cell survival, cell cycle control, differentiation, homocysteine/methionine/folate regulation, body temperature regulation, endocytosis, neuronal development, synaptic plasticity, etc. Abnormal expression and/or activity of some of these kinases, DYRK1A in particular, is seen in many human nervous system diseases, such as cognitive deficits associated with Down syndrome, Alzheimer’s disease and related diseases, tauopathies, dementia, Pick’s disease, Parkinson’s disease and other neurodegenerative diseases, Phelan-McDermid syndrome, autism, and CDKL5 deficiency disorder. DYRKs and CLKs are also involved in diabetes, abnormal folate/methionine metabolism, osteoarthritis, several solid cancers (glioblastoma, breast, and pancreatic cancers) and leukemias (acute lymphoblastic leukemia, acute megakaryoblastic leukemia), viral infections (influenza, HIV-1, HCMV, HCV, CMV, HPV), as well as infections caused by unicellular parasites (Leishmania, Trypanosoma, Plasmodium). This variety of pathological implications calls for (1) a better understanding of the regulations and substrates of DYRKs and CLKs and (2) the development of potent and selective inhibitors of these kinases and their evaluation as therapeutic drugs. This article briefly reviews the current knowledge about DYRK/CLK kinases and their implications in human disease.

scholarly journals The Antiviral Properties of Cyclosporine. Focus on Coronavirus, Hepatitis C Virus, Influenza Virus, and Human Immunodeficiency Virus Infections

Biology ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 192 ◽  
Author(s):  
Paulina Glowacka ◽  
Lidia Rudnicka ◽  
Olga Warszawik-Hendzel ◽  
Mariusz Sikora ◽  
Mohamad Goldust ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Influenza Virus ◽  
Hepatitis C ◽  
Beneficial Effect ◽  
Bacterial Infections ◽  
Viral Infections ◽  
Skin Diseases ◽  
Current Knowledge ◽  
Immunosuppressive Treatment ◽  
Immunodeficiency Virus

This review updates current knowledge regarding the risk of viral infections, including COVID-19, in patients treated with cyclosporine. We also shortly refer to bacterial infections and parasitic infestations in patients treated with cyclosporin. Cyclosporine is an immunosuppressive drug, which is widely used in medicine, including in the treatment of autoimmune skin diseases in dermatology, rheumatology, ophthalmology and nephrology, and in organ transplantation. A usual concern associated with immunosuppressive treatment is the potential risk of infections. Interestingly, several data indicate a relatively low risk of infections, especially viral infections, in patients receiving cyclosporine. It was shown that cyclosporine exerts an inhibitory effect on the replication of some viruses, or may have a potentially beneficial effect on the disease course in infections. These include hepatitis C, influenza virus, rotavirus, human immunodeficiency virus and coronavirus infections. Available data indicate that cyclosporine may have a beneficial effect on COVID-19, which is caused by the coronavirus SARS-COV2.

Postischemic Revascularization: From Cellular and Molecular Mechanisms to Clinical Applications

2013 ◽  
Vol 93 (4) ◽  
pp. 1743-1802 ◽  
Author(s):  
Jean-Sébastien Silvestre ◽  
David M. Smadja ◽  
Bernard I. Lévy
Keyword(s):  
Progenitor Cells ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Therapeutic Option ◽  
Vascular Wall ◽  
Arterial Disease ◽  
Cellular Mechanisms ◽  
Collateral Growth ◽  
Vessel Growth ◽  
Ischemic Diseases

After the onset of ischemia, cardiac or skeletal muscle undergoes a continuum of molecular, cellular, and extracellular responses that determine the function and the remodeling of the ischemic tissue. Hypoxia-related pathways, immunoinflammatory balance, circulating or local vascular progenitor cells, as well as changes in hemodynamical forces within vascular wall trigger all the processes regulating vascular homeostasis, including vasculogenesis, angiogenesis, arteriogenesis, and collateral growth, which act in concert to establish a functional vascular network in ischemic zones. In patients with ischemic diseases, most of the cellular (mainly those involving bone marrow-derived cells and local stem/progenitor cells) and molecular mechanisms involved in the activation of vessel growth and vascular remodeling are markedly impaired by the deleterious microenvironment characterized by fibrosis, inflammation, hypoperfusion, and inhibition of endogenous angiogenic and regenerative programs. Furthermore, cardiovascular risk factors, including diabetes, hypercholesterolemia, hypertension, diabetes, and aging, constitute a deleterious macroenvironment that participates to the abrogation of postischemic revascularization and tissue regeneration observed in these patient populations. Thus stimulation of vessel growth and/or remodeling has emerged as a new therapeutic option in patients with ischemic diseases. Many strategies of therapeutic revascularization, based on the administration of growth factors or stem/progenitor cells from diverse sources, have been proposed and are currently tested in patients with peripheral arterial disease or cardiac diseases. This review provides an overview from our current knowledge regarding molecular and cellular mechanisms involved in postischemic revascularization, as well as advances in the clinical application of such strategies of therapeutic revascularization.

Sign in / Sign up

Export Citation Format

Share Document