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orthosilicic acid

Christian Zerfaß, Garry W Buchko, Wendy J Shaw, Stephan Hobe, Harald Paulsen
The silica forming repeat R5 of sil1 from Cylindrotheca fusiformis was the blueprint for the design of P5 S3 , a 50-residue peptide which can be produced in large amounts by recombinant bacterial expression. It contains 5 protein kinase A target sites and is highly cationic due to 10 lysine and 10 arginine residues. In the presence of supersaturated orthosilicic acid P5 S3 enhances silica-formation whereas it retards the dissolution of amorphous silica (SiO2 ) at globally undersaturated concentrations. The secondary structure of P5 S3 during these 2 processes was studied by circular dichroism (CD) spectroscopy, complemented by nuclear magnetic resonance (NMR) spectroscopy of the peptide in the absence of silicate...
November 2017: Proteins
Masayasu Igarashi, Tomohiro Matsumoto, Fujio Yagihashi, Hiroshi Yamashita, Takashi Ohhara, Takayasu Hanashima, Akiko Nakao, Taketo Moyoshi, Kazuhiko Sato, Shigeru Shimada
Orthosilicic acid (Si(OH)4) and its small condensation compounds are among the most important silicon compounds but have never been isolated, due to their instability. These compounds would be highly useful building blocks for advanced materials if they became available at high purity. Here we show a simple procedure to selectively synthesize orthosilicic acid and its dimer, cyclic trimer and tetramer in organic solvents. Isolation of orthosilicic acid, the dimer and the cyclic tetramer as hydrogen-bonded crystals with tetrabutylammonium halides and the cyclic trimer as solvent-containing crystals is also described...
July 26, 2017: Nature Communications
Sandrine Quignard, Thibaud Coradin, Jonathan J Powell, Ravin Jugdaohsingh
There is good evidence that certain silicon-containing materials promote would healing and their common feature is the delivery of orthosilicic acid (Si(OH)4 ) either directly or following metabolism. In this respect, amorphous silica nanoparticles (NP), which dissolve in aqueous environments releasing up to 2mM orthosilicic acid, may be appropriate 'slow release' vehicles for bioactive silicon. Here we studied the impact of silica NP suspensions (primary particles∼10nm) in undersaturated conditions (below 2mM Si) with differing degrees of surface charge and dissolution rate on human dermal fibroblasts (CCD-25SK cells) viability, proliferation and migration in a cellular wound model...
July 1, 2017: Colloids and Surfaces. B, Biointerfaces
Hong-Ye Yang, Li-Na Niu, Jin-Long Sun, Xue-Qing Huang, Dan-Dan Pei, Cui Huang, Franklin R Tay
Scaffold supplements such as nanoparticles, components of the extracellular matrix, or growth factors have been incorporated in conventional scaffold materials to produce smart scaffolds for tissue engineering of damaged hard tissues. Due to increasing concerns on the clinical side effects of using large doses of recombinant bone-morphogenetic protein-2 in bone surgery, it is desirable to develop an alternative nanoscale scaffold supplement that is not only osteoinductive, but is also multifunctional in that it can perform other significant bone regenerative roles apart from stimulation of osteogenic differentiation...
2017: International Journal of Nanomedicine
Piet Geusens, Karel Pavelka, Jozef Rovensky, Johan Vanhoof, Nathalie Demeester, Mario Calomme, Dirk Vanden Berghe
BACKGROUND: The aim of this study was to assess the efficacy of choline-stabilized orthosilicic acid (ch-OSA) in patients with symptomatic knee osteoarthritis (OA). METHODS: In a multicenter, double-blind, placebo-controlled study, 211 patients with knee OA (Kellgren and Lawrence grade II or III) and moderate to moderately severe pain were randomly allocated to ch-OSA or placebo for 12 weeks. The primary outcome was the change in the WOMAC pain subscale from baseline to week 12...
January 5, 2017: BMC Musculoskeletal Disorders
Hyun-Jun Jang, Young-Kwon Seo
Our investigation focused on identifying melanogenesis effect of soluble minerals in rice bran ash extract (RBE) which include orthosilicic acid (OSA). Melanocytes were apparently normal in terms of morphology. It was, however, shown that they were stressed a little in the RBE and OSA added media in aspect of LDH activity. Melanin synthesis and intracellular tyrosinase activity were increased by treatment of RBE which is similar to that of OSA. The Western blotting results showed that TRP-1, tyrosinase, and MITF expression levels were 2-3 times higher in the OSA and RBE groups compared to the control group which promoted melanin synthesis through CREB phosphorylation...
2016: Evidence-based Complementary and Alternative Medicine: ECAM
Anna Pielesz, Dorota Biniaś, Ewa Sarna, Rafał Bobiński, Marek Kawecki, Justyna Glik, Agnieszka Klama-Baryła, Diana Kitala, Wojciech Łabuś, Jadwiga Paluch, Małgorzata Kraut
Being a complex traumatic event, burn injury also affects other organ systems apart from the skin. Wounds undergo various pathological changes which are accompanied by alterations in the molecular environment. Information about molecules may be obtained with the use of Raman spectroscopy and Fourier-transform infrared spectroscopy, and when combined, both methods are a powerful tool for providing material characterization. Alterations in the molecular environment may lead to identifying objective markers of acute wound healing...
February 15, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Thérèse Sergent, Karine Croizet, Yves-Jacques Schneider
SCOPE: Silicon (Si) is one of the most abundant trace elements in the body. Although pharmacokinetics data described its absorption from the diet and its body excretion, the mechanisms involved in the uptake and transport of Si across the gut wall have not been established. METHODS AND RESULTS: Caco-2 cells were used as a well-accepted in vitro model of the human intestinal epithelium to investigate the transport, across the intestinal barrier in both the absorption and excretion directions, of Si supplied as orthosilicic acid stabilized by vanillin complex (OSA-VC)...
February 2017: Molecular Nutrition & Food Research
Gabriel A Carpentier, Alexandre P Garneau, Andrée-Anne Marcoux, Micheline Noël, Rachelle Frenette-Cotton, Paul Isenring
We recently demonstrated that the aquaglyceroporins (AQGPs) could act as potent transporters for orthosilicic acid (H4SiO4). Although interesting, this finding raised the question of whether water and H4SiO4, the transportable form of Si, permeate AQGPs by interacting with the same region of the pore, especially in view of the difference in molecular radius between the two substrates. Here, our goal was to identify residues that endow the AQGPs with the ability to facilitate Si diffusion by examining the transport characteristics of mutants in which residues were interchanged between a water-permeable but Si-impermeable channel (aquaporin 1 [AQP1]) and a Si-permeable but water-impermeable channel (AQP10)...
September 2016: Journal of General Physiology
Lidiane Advincula de Araújo, Flavia Addor, Patrícia Maria Berardo Gonçalves Maia Campos
Silicon is the second most abundant element on Earth, and the third most abundant trace element in human body. It is present in water, plant and animal sources. On the skin, it is suggested that silicon is important for optimal collagen synthesis and activation of hydroxylating enzymes, improving skin strength and elasticity. Regarding hair benefits, it was suggested that a higher silicon content in the hair results in a lower rate of hair loss and increased brightness. For these beneficial effects, there is growing interest in scientific studies evaluating the efficacy and safety of using dietary supplements containing silicon...
May 2016: Anais Brasileiros de Dermatologia
Xianfeng Zhou, Fouad M Moussa, Steven Mankoci, Putu Ustriyana, Nianli Zhang, Samir Abdelmagid, Jim Molenda, William L Murphy, Fayez F Safadi, Nita Sahai
UNLABELLED: Accumulating evidence over the last 40years suggests that silicate from dietary as well as silicate-containing biomaterials is beneficial to bone formation. However, the exact biological role(s) of silicate on bone cells are still unclear and controversial. Here, we report that orthosilicic acid (Si(OH)4) stimulated human mesenchymal stem cells (hMSCs) osteoblastic differentiation in vitro. To elucidate the possible molecular mechanisms, differential microRNA microarray analysis was used to show that Si(OH)4 significantly up-regulated microRNA-146a (miR-146a) expression during hMSC osteogenic differentiation...
July 15, 2016: Acta Biomaterialia
Meng Dong, Guangjun Jiao, Haichun Liu, Wenliang Wu, Shangzhi Li, Qingshi Wang, Daxia Xu, Xiaofeng Li, Huan Liu, Yunzhen Chen
Silicon is essential for bone formation. A low-silicon diet leads to bone defects, and numerous animal models have demonstrated that silicon supplementation increases bone mineral density (BMD) and reduces bone fragility. However, the exact mechanism of this action has not been characterized. In this study, we aimed to determine the role of biological silicon in the induction of osteoblast differentiation and the possible underlying mechanism. We examined whether orthosilicic acid promotes collagen type 1 (COL-1) and osteocalcin synthesis through the bone morphogenetic protein-2 (BMP-2)/Smad1/5/runt-related transcription factor 2 (RUNX2) signaling pathway by investigating its effect in vitro at several concentrations on COL-1 and osteocalcin synthesis in human osteosarcoma cell lines (MG-63 and U2-OS)...
October 2016: Biological Trace Element Research
Tomasz Kleiber, Mario Calomme, Klaudia Borowiak
The aim of experiments was to assess the efficiency of choline-stabilized orthosilicic acid (ch-OSA; complex of orthosilicic acid with choline and a bioavailable source of silicon) application under increasing manganese (Mn) stress on the micronutritional composition and yielding of tomato (Solanum lycopersicum L. cvs. 'Alboney F1' and 'Emotion F1'). Plants were grown in rockwool with the application of a nutrient solution varied the Mn concentrations (in mg dm(-3)): 9.6 and 19.2 which cause strong oxidative stress of plants comparing with optimal concentration of that microelement in nutrient solution...
November 2015: Plant Physiology and Biochemistry: PPB
Aline Marcowycz, Béatrice Housez, Corinne Maudet, Murielle Cazaubiel, Guiseppe Rinaldi, Karine Croizet
SCOPE: Silicon (Si) is an abundant element on earth. It is found naturally in water in the form of orthosilicic acid (OSA), however this form is not stable under certain conditions such as in highly concentrated and non-neutral pH solutions, which lead to its polymerization and reduced bioavailability. This study aimed to assess the bioavailability of Si from OSA stabilized by vanillin (OSA-VC). METHODS AND RESULTS: This was a single-center, double-blind, cross-over randomized controlled trial...
August 2015: Molecular Nutrition & Food Research
Adriaan Smis, Francisco Javier Ancin Murguzur, Eric Struyf, Eeva M Soininen, Juan G Herranz Jusdado, Patrick Meire, Kari Anne Bråthen
Silicon (Si) is one of the most common elements in the earth bedrock, and its continental cycle is strongly biologically controlled. Yet, research on the biogeochemical cycle of Si in ecosystems is hampered by the time and cost associated with the currently used chemical analysis methods. Here, we assessed the suitability of Near Infrared Reflectance Spectroscopy (NIRS) for measuring Si content in plant tissues. NIR spectra depend on the characteristics of the present bonds between H and N, C and O, which can be calibrated against concentrations of various compounds...
2014: Frontiers in Plant Science
Dirk A Vanden Berghe
: This article is in response to Jugdaohsingh et al.: The silicon supplement 'Monomethylsilanetriol' is safe and increases the body pool of silicon in healthy Pre-menopausal women. Nutrition & Metabolism 2013 10:37: The response from the authors is published as Jugdaohsingh et al.: Response to Prof D. Vanden Berghe letter: 'There are not enough data to conclude that Monomethylsilanetriol is safe'. Nutrition & Metabolism 2013 10:65: http://www.nutritionandmetabolism...
2013: Nutrition & Metabolism
Keith R Martin
Silicon is the second most abundant element in nature behind oxygen. As a metalloid, silicon has been used in many industrial applications including use as an additive in the food and beverage industry. As a result, humans come into contact with silicon through both environmental exposures but also as a dietary component. Moreover, many forms of silicon, that is, Si bound to oxygen, are water-soluble, absorbable, and potentially bioavailable to humans presumably with biological activity. However, the specific biochemical or physiological functions of silicon, if any, are largely unknown although generally thought to exist...
2013: Metal Ions in Life Sciences
Supannee Pruksa, Atitaya Siripinyanond, Jonathan J Powell, Ravin Jugdaohsingh
BACKGROUND: Accumulating evidence suggests a role for silicon in optimal connective tissue health. Further proof of its importance/essentiality may be provided by studies involving imposed depletion followed by 29Si challenge to estimate metabolic balance. Prior to conducting these expensive studies, we first established the variance of estimating normal Si excretion versus intake using a single oral dose of typical dietary Si, orthosilicic acid. METHODS: Healthy volunteers were recruited from Loei Rajabhat University, separated into two matched groups (three males and three females/group) and maintained on a standardized diet for the three study days...
January 9, 2014: Nutrition & Metabolism
Rita Mukhopadhyay, Hiranmoy Bhattacharjee, Barry P Rosen
BACKGROUND: Aquaporins (AQPs), members of a superfamily of transmembrane channel proteins, are ubiquitous in all domains of life. They fall into a number of branches that can be functionally categorized into two major sub-groups: i) orthodox aquaporins, which are water-specific channels, and ii) aquaglyceroporins, which allow the transport of water, non-polar solutes, such as urea or glycerol, the reactive oxygen species hydrogen peroxide, and gases such as ammonia, carbon dioxide and nitric oxide and, as described in this review, metalloids...
May 2014: Biochimica et Biophysica Acta
Vera Grotheer, Maria Goergens, Paul C Fuchs, Sebastian Dunda, Norbert Pallua, Joachim Windolf, Christoph V Suschek
In the present work, we have examined the impact of an inorganic orthosilicic acid-releasing spun fiber fleece (SIFIB) on wound closure in a porcine wound model in vivo as well as on wound healing-relevant parameters in vitro. In vivo SIFIB was completely bio-degradable and had no negative effects on wound closure or the wound healing process. In the in vitro experiments, SIFIB had no negative effects on proliferation of human skin fibroblast (FB) and endothelial cell (EC) cultures but strongly retarded the growth of the human monocyte cell line THP-1, and effectively inhibited human skin keratinocyte (KC) proliferation, which based on significantly enhanced KC differentiation...
October 2013: Biomaterials
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