Silver Nanomaterials in Contemporary Molecular Physiology Research

Silver nanoparticles have numerous potential applications in engineering, industry, biology and medicine. Because of their unique chemical properties, they have become the focus of many research teams all over the world. Silver nanoparticles may exhibit significant antimicrobial and anticancer effects, and they may be a valuable part of various bioassays and biosensors. However, the research on biological and medical uses of AgNPs is related with numerous potential problems and challenges that need to be overcome in the years ahead. Possible toxic effects of silver nanoparticles on living organisms represent a great concern, both in clinical medicine and public health. Nevertheless, in the future, it may be expected that all metallic nanomaterials, including the ones made from silver will greatly benefit almost all natural scientific fields. In this short review, we focus on the recent research on silver nanoparticles in experimental physiology, as well as other areas of fundamental and clinical medicine.

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Shape-Controlled Syntheses of Silver Nanoparticles: Role of the Seeds

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.2402 ◽

2010 ◽

Vol 654-656 ◽

pp. 2402-2405 ◽

Cited By ~ 1

Author(s):

Chu Yang Chen ◽

Xu Chuan Jiang ◽

Shi Xian Xiong ◽

Ai Bing Yu

Keyword(s):

Silver Nanoparticles ◽

Metallic Nanoparticles ◽

Chemical Properties ◽

Biochemical Sensors ◽

Oxidative Etching ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Heating Treatment ◽

Potential Applications ◽

Shape Controlled

Precious metallic nanoparticles have attracted considerable attention because of their unique properties (optical, electronic, and chemical properties) and potential applications in many areas such as optical probes, biochemical sensors, and surface enhanced Raman Spectrum. Despite many successes in synthesis of anisotropic nanoparticles (rods, plates), some limitations still exist in generating monodispersed silver nanoparticles. This study intends to elucidate the influence of crystalline seeds on the shape, size, and size distribution of nanoparticles through a seed-mediated method. The crystalline seeds can be modified by using different ways, such as heating treatment and oxidative etching. The shape and size of the generated particles will be characterized by TEM, and the particle formation and growth is tracked by UV-vis spectrometry. The findings would be useful for the shape-controlled synthesis of metal nanoparticles for desired functional properties.

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Coating-Dependent Effects of Silver Nanoparticles on Tobacco Seed Germination and Early Growth

International Journal of Molecular Sciences ◽

10.3390/ijms21103441 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3441 ◽

Cited By ~ 1

Author(s):

Renata Biba ◽

Dajana Matić ◽

Daniel Mark Lyons ◽

Petra Peharec Štefanić ◽

Petra Cvjetko ◽

...

Keyword(s):

Silver Nanoparticles ◽

Growth Parameters ◽

Antimicrobial Properties ◽

Chemical Properties ◽

Early Growth ◽

Consumer Products ◽

Negative Effects ◽

Wide Range ◽

Living Organisms ◽

The Stability

Silver nanoparticles (AgNPs) are used in a wide range of consumer products because of their excellent antimicrobial properties. AgNPs released into the environment are prone to transformations such as aggregation, oxidation, or dissolution so they are often stabilised by coatings that affect their physico-chemical properties and change their effect on living organisms. In this study we investigated the stability of polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide (CTAB) coated AgNPs in an exposure medium, as well as their effect on tobacco germination and early growth. AgNP-CTAB was found to be more stable in the solid Murashige and Skoog (MS) medium compared to AgNP-PVP. The uptake and accumulation of silver in seedlings was equally efficient after exposure to both types of AgNPs. However, AgNP-PVP induced only mild toxicity on seedlings growth, while AgNP-CTAB caused severe negative effects on all parameters, even compared to AgNO3. Moreover, CTAB coating itself exerted negative effects on growth. Cysteine addition generally alleviated AgNP-PVP-induced negative effects, while it failed to improve germination and growth parameters after exposure to AgNP-CTAB. These results suggest that the toxic effects of AgNP-PVP are mainly a consequence of release of Ag+ ions, while phytotoxicity of AgNP-CTAB can rather be ascribed to surface coating itself.

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Hyperinsulinism in Infancy: From Basic Science to Clinical Disease

Physiological Reviews ◽

10.1152/physrev.00022.2003 ◽

2004 ◽

Vol 84 (1) ◽

pp. 239-275 ◽

Cited By ~ 190

Author(s):

MARK J. DUNNE ◽

KAREN E. COSGROVE ◽

RUTH M. SHEPHERD ◽

ALBERT AYNSLEY-GREEN ◽

KEITH J. LINDLEY

Keyword(s):

Ion Channel ◽

Basic Science ◽

Cell Biology ◽

Clinical Medicine ◽

Cell Metabolism ◽

Cell Types ◽

Clinical Disease ◽

Molecular Physiology ◽

Almost All ◽

The Relationship

Dunne, Mark J., Karen E. Cosgrove, Ruth M. Shepherd, Albert Aynsley-Green, and Keith J. Lindley. Hyperinsulinism in Infancy: From Basic Science to Clinical Disease. Physiol Rev 84: 239–275, 2004; 10.1152/physrev.00022.2003.—Ion channelopathies have now been described in many well-characterized cell types including neurons, myocytes, epithelial cells, and endocrine cells. However, in only a few cases has the relationship between altered ion channel function, cell biology, and clinical disease been defined. Hyperinsulinism in infancy (HI) is a rare, potentially lethal condition of the newborn and early childhood. The causes of HI are varied and numerous, but in almost all cases they share a common target protein, the ATP-sensitive K+ channel. From gene defects in ion channel subunits to defects in β-cell metabolism and anaplerosis, this review describes the relationship between pathogenesis and clinical medicine. Until recently, HI was generally considered an orphan disease, but as parallel defects in ion channels, enzymes, and metabolic pathways also give rise to diabetes and impaired insulin release, the HI paradigm has wider implications for more common disorders of the endocrine pancreas and the molecular physiology of ion transport.

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Short Review and opinion: New matter properties and applications based on Hybrids Graphene based Metamaterials

Current Graphene Science ◽

10.2174/2452273204999200528141157 ◽

2020 ◽

Vol 04 ◽

Author(s):

A. Guillermo Bracamonte

Keyword(s):

Short Review ◽

New Materials ◽

Design And Synthesis ◽

Chemical Structures ◽

Current State ◽

Potential Applications ◽

Fundamental Research ◽

Miniaturized Instrumentation ◽

And Control ◽

Conductive Properties

: Graphene as Organic material showed special attention due to their electronic and conductive properties. Moreover, its highly conjugated chemical structures and relative easy modification permitted varied design and control of targeted properties and applications. In addition, this Nanomaterial accompanied with pseudo Electromagnetic fields permitted photonics, electronics and Quantum interactions with their surrounding that generated new materials properties. In this context, this short Review, intends to discuss many of these studies related with new materials based on graphene for light and electronic interactions, conductions, and new modes of non-classical light generation. It should be highlighted that these new materials and metamaterials are currently in progress. For this reason it was showed and discussed some representative examples from Fundamental Research with Potential Applications as well as for their incorporations to real Advanced devices and miniaturized instrumentation. In this way, it was proposed this Special issue entitled “Design and synthesis of Hybrids Graphene based Metamaterials”, in order to open and share the knowledge of the Current State of the Art in this Multidisciplinary field.

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Modulation of Innate Immune Toxicity by Silver Nanoparticle Exposure and the Preventive Effects of Pterostilbene

International Journal of Molecular Sciences ◽

10.3390/ijms22052536 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2536

Author(s):

Rong-Jane Chen ◽

Chiao-Ching Huang ◽

Rosita Pranata ◽

Yu-Hsuan Lee ◽

Yu-Ying Chen ◽

...

Keyword(s):

Silver Nanoparticles ◽

Good Alternative ◽

Innate Immune ◽

Toxic Effects ◽

Transgenic Zebrafish ◽

Zebrafish Model ◽

Cytokines And Chemokines ◽

Living Organisms ◽

And Function ◽

Immune Toxicity

Silver nanoparticles pose a potential risk to ecosystems and living organisms due to their widespread use in various fields and subsequent gradual release into the environment. Only a few studies have investigated the effects of silver nanoparticles (AgNPs) toxicity on immunological functions. Furthermore, these toxic effects have not been fully explored. Recent studies have indicated that zebrafish are considered a good alternative model for testing toxicity and for evaluating immunological toxicity. Therefore, the purpose of this study was to investigate the toxicity effects of AgNPs on innate immunity using a zebrafish model and to investigate whether the natural compound pterostilbene (PTE) could provide protection against AgNPs-induced immunotoxicity. Wild type and neutrophil- and macrophage-transgenic zebrafish lines were used in the experiments. The results indicated that the exposure to AgNPs induced toxic effects including death, malformation and the innate immune toxicity of zebrafish. In addition, AgNPs affect the number and function of neutrophils and macrophages. The expression of immune-related cytokines and chemokines was also affected. Notably, the addition of PTE could activate immune cells and promote their accumulation in injured areas in zebrafish, thereby reducing the damage caused by AgNPs. In conclusion, AgNPs may induce innate immune toxicity and PTE could ameliorate this toxicity.

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Silver Nanoparticles Stabilized with Phosphorus-Containing Heterocyclic Surfactants: Synthesis, Physico-Chemical Properties, and Biological Activity Determination

Nanomaterials ◽

10.3390/nano11081883 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1883

Author(s):

Martin Pisárčik ◽

Miloš Lukáč ◽

Josef Jampílek ◽

František Bilka ◽

Andrea Bilková ◽

...

Keyword(s):

Silver Nanoparticles ◽

Biological Activity ◽

Zeta Potential ◽

Chain Length ◽

Alkyl Chain ◽

Chemical Properties ◽

Alkyl Chain Length ◽

Microbial Pathogens ◽

Physico Chemical ◽

Phosphorus Containing

Phosphorus-containing heterocyclic cationic surfactants alkyldimethylphenylphospholium bromides with the alkyl chain length 14 to 18 carbon atoms were used for the stabilization of silver nanodispersions. Zeta potential of silver nanodispersions ranges from +35 to +70 mV, which indicates the formation of stable silver nanoparticles (AgNPs). Long-chain heptadecyl and octadecyl homologs of the surfactants series provided the most intensive stabilizing effect to AgNPs, resulting in high positive zeta potential values and smaller diameter of AgNPs in the range 50–60 nm. A comparison with non-heterocyclic alkyltrimethylphosphonium surfactants of the same alkyl chain length showed better stability and more positive zeta potential values for silver nanodispersions stabilized with heterocyclic phospholium surfactants. Investigations of biological activity of phospholium-capped AgNPs are represented by the studies of antimicrobial activity and cytotoxicity. While cytotoxicity results revealed an increased level of HepG2 cell growth inhibition as compared with the cytotoxicity level of silver-free surfactant solutions, no enhanced antimicrobial action of phospholium-capped AgNPs against microbial pathogens was observed. The comparison of cytotoxicity of AgNPs stabilized with various non-heterocyclic ammonium and phosphonium surfactants shows that AgNPs capped with heterocyclic alkyldimethylphenylphospholium and non-heterocyclic triphenyl-substituted phosphonium surfactants have the highest cytotoxicity among silver nanodispersions stabilized by the series of ammonium and phosphonium surfactants.

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Metal Binding Proteins

Encyclopedia ◽

10.3390/encyclopedia1010024 ◽

2021 ◽

Vol 1 (1) ◽

pp. 261-292

Author(s):

Eugene A. Permyakov

Keyword(s):

Metal Ions ◽

Metal Binding ◽

Transition Metal Ions ◽

Short Review ◽

Sodium Potassium ◽

Physical Chemical ◽

Physiological Properties ◽

Cell Processes ◽

Living Organisms ◽

Potassium Magnesium

Metal ions play several major roles in proteins: structural, regulatory, and enzymatic. The binding of some metal ions increase stability of proteins or protein domains. Some metal ions can regulate various cell processes being first, second, or third messengers. Some metal ions, especially transition metal ions, take part in catalysis in many enzymes. From ten to twelve metals are vitally important for activity of living organisms: sodium, potassium, magnesium, calcium, manganese, iron, cobalt, zinc, nickel, vanadium, molybdenum, and tungsten. This short review is devoted to structural, physical, chemical, and physiological properties of proteins, which specifically bind these metal cations.

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Composite Poly(vinyl alcohol)-Based Nanofibers Embedding Differently-Shaped Gold Nanoparticles: Preparation and Characterization

Polymers ◽

10.3390/polym13101604 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1604

Author(s):

Andrea Dodero ◽

Maila Castellano ◽

Paola Lova ◽

Massimo Ottonelli ◽

Elisabetta Brunengo ◽

...

Keyword(s):

Vinyl Alcohol ◽

Ad Hoc ◽

Chemical Reduction ◽

Chemical Properties ◽

Single Step ◽

Gold Nanostructures ◽

Poly Vinyl Alcohol ◽

Spherical Nanoparticles ◽

Potential Applications ◽

New Perspective

Poly(vinyl alcohol) nanofibrous mats containing ad hoc synthesized gold nanostructures were prepared via a single-step electrospinning procedure and investigated as a novel composite platform with several potential applications. Specifically, the effect of differently shaped and sized gold nanostructures on the resulting mat physical-chemical properties was investigated. In detail, nearly spherical nanoparticles and nanorods were first synthesized through a chemical reduction of gold precursors in water by using (hexadecyl)trimethylammonium bromide as the stabilizing agent. These nanostructures were then dispersed in poly(vinyl alcohol) aqueous solutions to prepare nanofibrous mats, which were then stabilized via a humble thermal treatment able to enhance their thermal stability and water resistance. Remarkably, the nanostructure type was proven to influence the mesh morphology, with the small spherical nanoparticles and the large nanorods leading to thinner well defined or bigger defect-rich nanofibers, respectively. Finally, the good mechanical properties shown by the prepared composite mats suggest their ease of handleability thereby opening new perspective applications.

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The Diverse Calpain Family in Trypanosomatidae: Functional Proteins Devoid of Proteolytic Activity?

Cells ◽

10.3390/cells10020299 ◽

2021 ◽

Vol 10 (2) ◽

pp. 299

Author(s):

Vítor Ennes-Vidal ◽

Marta Helena Branquinha ◽

André Luis Souza dos Santos ◽

Claudia Masini d’Avila-Levy

Keyword(s):

Proteolytic Activity ◽

Current Knowledge ◽

Current Therapy ◽

Calcium Dependent ◽

Administration Routes ◽

Life Threatening ◽

Living Organisms ◽

Almost All ◽

Open Question ◽

Calpain Inhibitors

Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?

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A Review on Coordination Properties of Al(III) and Fe(III) toward Natural Antioxidant Molecules: Experimental and Theoretical Insights

Molecules ◽

10.3390/molecules26092603 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2603

Author(s):

Luana Malacaria ◽

Giuseppina Anna Corrente ◽

Amerigo Beneduci ◽

Emilia Furia ◽

Tiziana Marino ◽

...

Keyword(s):

Chemical Properties ◽

Natural Antioxidants ◽

Point Of View ◽

Water Soluble ◽

Natural Antioxidant ◽

Theoretical Point ◽

Structure And Properties ◽

Coordination Properties ◽

Soluble Molecule ◽

Living Organisms

This review focuses on the ability of some natural antioxidant molecules (i.e., hydroxycinnamic acids, coumarin-3-carboxylic acid, quercetin, luteolin and curcumin) to form Al(III)- and Fe(III)-complexes with the aim of evaluating the coordination properties from a combined experimental and theoretical point of view. Despite the contributions of previous studies on the chemical properties and biological activity of these metal complexes involving such natural antioxidants, further detailed relationships between the structure and properties are still required. In this context, the investigation on the coordination properties of Al(III) and Fe(III) toward these natural antioxidant molecules might deserve high interest to design water soluble molecule-based metal carriers that can improve the metal’s intake and/or its removal in living organisms.

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