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Topic Review
Reactive Oxygen Species in the Brain
Reactive oxygen and nitrogen species are crucial contributors to the age-dependent decline in all tissues. Neural tissue, one of the main oxygen consumers in the mammalian body, is especially prone to reactive species-mediated damage. Brain cells, including neurons, astrocytes, and microglia, produce reactive oxygen species (ROS) by specific enzymatic systems, including complexes of the mitochondrial respiratory chain, multienzyme flavin-containing complexes, monoamine and xanthine oxidases, microglial and endothelial NADPH oxidases and cyclooxygenases in addition to non-enzymatic and potentially uncontrolled mechanisms of ROS production, such as autooxidation of quinones or other aromatic compounds. Nitric oxide produced by nitric oxide synthases powers the conversion of ROS into reactive nitrogen species (RNS). Both ROS and RNS play important signaling roles and are also capable of modifying other molecules such as proteins, nucleic and fatty acids, lipids and carbohydrates. The antioxidant system, comprising low molecular mass antioxidants (e.g., tocopherol, ascorbic acid and glutathione) and high molecular mass antioxidants such as enzymes (e.g., catalases, peroxidases, superoxide dismutases) and others, protects cells from potential damage caused by ROS or RNS. Powering antioxidant systems by NADPH provides neural tissue with defense against ROS but may also trigger ROS production by NADPH oxidases and cyclooxygenases. In turn, mitochondria start using ketone bodies as an energy source under certain conditions. Increased steady-state levels of ROS and RNS, along with the aforementioned ROS-modified molecules, activate the organisms’ immune system including brain’s microglia.
  • 1.2K
  • 09 Nov 2021
Topic Review
Synthesis of Silver Nanostructure
Silver nanoparticles are one of the commonly used metal materials for SP because of their high sensitivity to refractive index change, convenient synthesis, and high controllable degree of shape and size. Silver nanoparticles of different sizes and shapes are used in many fields. Various synthesis methods have undergone many improvements over time and technological developments in order to provide precise control over the shape and size of the synthesized silver nanoparticles. Silver nanoparticle fabrication is usually divided into two categories: top-down and bottom-up.
  • 1.2K
  • 19 Apr 2023
Topic Review
Pulmonary Stem Cell Senescence and Differentiation Disorders
Pulmonary senescence is accelerated by unresolved DNA damage response, underpinning susceptibility to pulmonary fibrosis. Recently it was reported that the SARS-Cov-2 viral infection induces acute pulmonary epithelial senescence followed by fibrosis. Notably, the TGF-β signalling pathway mediates alveolar epithelial stem cell senescence by mechanisms involving suppression of the telomerase reverse transcriptase gene in pulmonary fibrosis. Alternatively, telomere uncapping caused by stress-induced telomeric shelterin protein TPP1 degradation mediates DNA damage response, pulmonary senescence and fibrosis. However, targeted intervention of cellular senescence disrupts pulmonary remodelling and fibrosis by clearing senescent cells using senolytics or preventing senescence using telomere dysfunction inhibitor (TELODIN). Studies indicate that the development of senescence-associated differentiation disorders is reprogrammable and reversible by inhibiting stem cell replicative senescence in pulmonary fibrosis, providing a framework for targeted intervention of the molecular mechanisms of alveolar stem cell senescence and pulmonary fibrosis.
  • 1.2K
  • 18 Mar 2022
Topic Review
Carotenoids Antioxidant and Anti-Inflammatory Effects in Mood Disorders
Depression has a multifactorial etiology comprising family history and unemployment. Antioxidant supplementation has been found to combat various stress-induced psychiatric disorders, including depression and anxiety. A growing body of evidence indicates that carotenoids have both antioxidant and anti-inflammatory. Studies also suggest that poor dietary intake, particularly low intakes of fruit and vegetables and high intakes of fast food and other convenience foods, may increase the risk of developing depression. Thus, dietary interventions have the potential to help mitigate the risk of mental health decline in both the general population and those with mood disorders. 
  • 1.2K
  • 17 Mar 2023
Topic Review
Glycosaminoglycans in Cancer Therapy
The tumor microenvironment (TME) is composed of cancerous, non-cancerous, stromal, and immune cells that are surrounded by the components of the extracellular matrix (ECM). Glycosaminoglycans (GAGs), natural biomacromolecules, essential ECM, and cell membrane components are extensively altered in cancer tissues. During disease progression, the GAG fine structure changes in a manner associated with disease evolution. Thus, changes in the GAG sulfation pattern are immediately correlated to malignant transformation. Their molecular weight, distribution, composition, and fine modifications, including sulfation, exhibit distinct alterations during cancer development. GAGs and GAG-based molecules, due to their unique properties, are suggested as promising effectors for anticancer therapy. Considering their participation in tumorigenesis, their utilization in drug development has been the focus of both industry and academic research efforts. These efforts have been developing in two main directions; (i) utilizing GAGs as targets of therapeutic strategies and (ii) employing GAGs specificity and excellent physicochemical properties for targeted delivery of cancer therapeutics.
  • 1.2K
  • 24 Mar 2021
Topic Review
Heme-Copper Oxidases with Nitrite and Nitric Oxide
Nitrite and nitric oxide (NO), two active and critical nitrogen oxides linking nitrate to dinitrogen gas in the broad nitrogen biogeochemical cycle, are capable of interacting with redox-sensitive proteins. The interactions of both with heme-copper oxidases (HCOs) serve as the foundation not only for the enzymatic interconversion of nitrogen oxides but also for the inhibitory activity.
  • 1.2K
  • 26 Jan 2022
Topic Review
Cholinesterase Modeling and Simulation
The cholinesterase enzyme family has but two members: acetylcholinesterase (AChE) and butyrylcholinesterase (BChE).  Computational efforts to better understand these enzymes, with a focus on their structural and catalytic properties and dynamics, includes docking and other Monte Carlo based calculations, as well as dynamic simulations of varying rigor and resource-demand including molecular dynamics, Langevin dynamics, quantum mechanical/molecular mechanics, and related algorithms. 
  • 1.2K
  • 21 Apr 2021
Topic Review
Selenium and Ageing
Selenium (Se) is an essential dietary trace element that plays an important role in the prevention of inflammation, cardiovascular diseases, infections, and cancer. Selenoproteins contain selenocysteine in the active center and include, i.a., the enzymes thioredoxin reductases (TXNRD1–3), glutathione peroxidases (GPX1–4 and GPX6) and methionine sulfoxide reductase, involved in immune functions, metabolic homeostasis, and antioxidant defense. Ageing is an inevitable process, which, i.a., involves an imbalance between antioxidative defense and reactive oxygen species (ROS), changes in protein and mitochondrial renewal, telomere attrition, cellular senescence, epigenetic alterations, and stem cell exhaustion. These conditions are associated with mild to moderate inflammation, which always accompanies the process of ageing and age-related diseases. In older individuals, Se, by being a component in protective enzymes, operates by decreasing ROS-mediated inflammation, removing misfolded proteins, decreasing DNA damage, and promoting telomere length. Se-dependent GPX1–4 and TXNRD1–3 directly suppress oxidative stress. Selenoprotein H in the cell nucleus protects DNA, and selenoproteins residing in the endoplasmic reticulum (ER) assist in the removal of misfolded proteins and protection against ER stress.
  • 1.2K
  • 11 Nov 2021
Topic Review
Cannabis and Cannabinoids for Treatment of Cancer
Cancer is a disease which affects approximately 40% of people in their lifetime. Chemotherapy, the primary choice for treatment of cancer, is often ineffective or/and presents itself with many debilitating side effects, including loss of appetite, nausea, insomnia, and anxiety. Components of cannabis extracts, including cannabinoids and terpenes, may present an alternative for controlling side effects and may be used for tumor shrinkage together with chemodrugs. Cannabinoids act on so called endocannabinoid system (ECS) that operates in human body to maintain homeostasis. ECS promotes healthy development of tissues and regulates many processes in our organism and when disbalanced may lead to disease, including cancer. 
  • 1.2K
  • 25 Oct 2022
Topic Review
Extracellular Vesicles Based Drug Delivery
Extracellular vesicles (EVs) play major roles in intracellular communication and participate in several biological functions in both normal and pathological conditions. Surface modification of EVs via various ligands, such as proteins, peptides, or aptamers, offers great potential as a means to achieve targeted delivery of therapeutic cargo, i.e., in drug delivery systems (DDS). This study summarizes recent studies pertaining to the development of EV-based DDS and its advantages compared to conventional nano drug delivery systems (NDDS). 
  • 1.2K
  • 30 Mar 2021
Topic Review
Radiolabeled Gold Nanoseeds and Glioblastoma Multiforme
Glioblastoma multiforme (GBM), classified as a grade IV brain tumor, represents the most frequent brain tumor, accounting for approximately 12–15% of all intracranial neoplasms. Current therapeutic strategies for GBM rely on open surgery, chemotherapy and radiotherapy. Despite some progress in the past 30 years, the overall survival of patients with glioblastoma remains extremely poor. The average lifespan is approximately 15 months after diagnosis, with most patients experiencing tumor relapse and outgrowth within 7–10 months of initial radiation therapy.
  • 1.2K
  • 14 Jan 2022
Topic Review
Curved Lipid Membranes
Eukaryotic cells contain membranes with various curvatures, from the near-plane plasma membrane to the highly curved membranes of organelles, vesicles, and membrane protrusions. These curvatures are generated and sustained by curvature-inducing proteins, peptides, and lipids, and describing these mechanisms is an important scientific challenge. In addition to that, some molecules can sense membrane curvature and thereby be trafficked to specific locations. 
  • 1.2K
  • 08 Aug 2022
Topic Review
Mechanisms of Neutrophil Activation
Neutrophil extracellular traps (NETs) are major contributors to inflammation and autoimmunity, playing a key role in the development of thrombotic disorders. NETs, composed of DNA, histones, and numerous other proteins serve as scaffolds for thrombus formation and promote platelet activation, coagulation, and endothelial dysfunction.
  • 1.2K
  • 03 Nov 2023
Topic Review
Thrombospondin-1 CD47 Signalling
Recent advances provide evidence that the cellular signalling pathway comprising the ligand-receptor duo of thrombospondin-1 (TSP1) and CD47 is involved in mediating a range of diseases affecting renal, vascular, and metabolic function, as well as cancer. In several instances, research has barely progressed past pre-clinical animal models of disease and early phase 1 clinical trials, while for cancers, anti-CD47 therapy has emerged from phase 2 clinical trials in humans as a crucial adjuvant therapeutic agent. This has important implications for interventions that seek to capitalize on targeting this pathway in diseases where TSP1 and/or CD47 play a role. Despite substantial progress made in our understanding of this pathway in malignant and cardiovascular disease, knowledge and translational gaps remain regarding the role of this pathway in kidney and metabolic diseases, limiting identification of putative drug targets and development of effective treatments. This review considers recent advances reported in the field of TSP1-CD47 signalling, focusing on several aspects including enzymatic production, receptor function, interacting partners, localization of signalling, matrix-cellular and cell-to-cell cross talk. The potential impact that these newly described mechanisms have on health, with a particular focus on renal and metabolic disease, is also discussed.
  • 1.2K
  • 02 Jul 2021
Topic Review
Plant Kunitz Inhibitors and Their Interaction with Proteases
Plant Kunitz inhibitors generally exhibit highly conserved primary structures. These inhibitors usually have a reactive site located in the region that binds to the enzyme, and the formation of the enzyme–inhibitor complex occurs in 1:1 stoichiometry. Their reactive sites are frequently composed of Arg and Lys; they may occasionally contain Glu, Ala, or Val.
  • 1.2K
  • 13 May 2022
Topic Review
Diagnosis of Hepatocellular Carcinoma
There are several risk factors of HCC such as viral hepatitis (B, C), cirrhosis, tobacco and alcohol use, aflatoxin-contaminated food, pesticides, diabetes, obesity, nonalcoholic fatty liver disease (NAFLD), and metabolic and genetic diseases. Diagnosis of HCC is based on different methods such as imaging ultrasonography (US), multiphasic enhanced computed tomography (CT), magnetic resonance imaging (MRI), and several diagnostic biomarkers.
  • 1.2K
  • 17 Jul 2023
Topic Review
Tumour Immune Microenvironment
Targeting altered tumour metabolism is an emerging therapeutic strategy for cancer treatment. The metabolic reprogramming that accompanies the development of malignancy creates targetable differences between cancer cells and normal cells, which may be exploited for therapy. In this entry, we focus on the metabolic dysregulation exerted by tumour cells on the immune microenvironment, leading to tumour immunosuppression. This metabolic rewiring and crosstalk with the tumour microenvironment also play a key role in cell proliferation, metastasis, and the development of treatment resistance. Nonetheless, greater understanding of the metabolic crosstalk presents strategies that aid in the precision targeting of altered tumour metabolism, including therapeutic strategies combining metabolic inhibition with immunotherapy.
  • 1.2K
  • 09 Dec 2020
Topic Review
PVT1: novel colorectal cancer biomarker
Colorectal cancer is a very deadly disease with a current lack of a reliable biomarker for early detection, non-invasive diagnosis, treatment, prognostication, and monitoring of treatment. This entry provides information that indicates that PVT1 is a novel biomarker in colorectal cancer. Further research is required to establish how this knowledge can be used for clinical applications.
  • 1.2K
  • 04 Aug 2020
Topic Review
Electrospinning Proteins for Wound Healing
In recent years, there has been a growing interest for electrospun polymeric wound dressings with fiber diameters in the nano- and micrometer range. Such wound dressings display a number of properties, which support and accelerate wound healing. For instance, they provide physical and mechanical protection, exhibit a high surface area, allow gas exchange, are cytocompatible and biodegradable, resemble the structure of the native extracellular matrix, and deliver antibacterial agents locally into the wound.
  • 1.2K
  • 22 Feb 2021
Topic Review
Mitochondrial Aging and Natural Products with Protective Potential
It was found that mitochondrial activity decreases with aging and that degeneration is linked to the reductions in mitochondria, mRNA transcripts, protein expression, and mtDNA and increased oxidative stress. In particular, reduced protein synthesis hinders protein turnover. The inability to replace damaged proteins may explain why aging is related to reduced mitochondrial function. Mitochondria, the cellular organelles that produce most of the ATP, become dysfunctional during aging. This condition is coupled with inflammation, oxidative stress, and reduced cellular functionalities in every organ. Numerous genes have been linked to aging, with some favoring it (gerontogenes) and others blocking it (genes of longevity pathways). The desire for eternal youth is a constant in the history of humanity. The increased life expectancy in industrialized countries has unfortunately also led to a significant increase in the incidence of age-related diseases (ARDs) such as neurodegenerative diseases, diabetes, cardiovascular diseases, and cancers.
  • 1.1K
  • 27 Dec 2022
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