A comparison of shear- and compression-induced mechanotransduction in SW1353 chondrocytes

Mapping Intimacies ◽

10.1101/2021.05.25.445657 ◽

2021 ◽

Author(s):

Hope D Welhaven ◽

Carley N McCutchen ◽

Ronald K June

Keyword(s):

Mechanical Stimuli ◽

Amino Acid Production ◽

Biological Phenomenon ◽

Beta Oxidation ◽

Biochemical Responses ◽

Cartilage Homeostasis ◽

Cyclical Loading ◽

Central Energy ◽

Cartilage Breakdown

Mechanotransduction is a biological phenomenon where mechanical stimuli are converted to biochemical responses. A model system for studying mechanotransduction are the chondrocytes of articular cartilage. Breakdown of this tissue results in decreased mobility, increased pain, and reduced quality of life. Either disuse or overloading can disrupt cartilage homeostasis, but physiological cyclical loading promotes cartilage homeostasis. To model this, we exposed SW1353 cells to cyclical mechanical stimuli, shear and compression, for different durations of time (15 and 30 min). By utilizing liquid chromatography-mass spectroscopy (LC-MS), metabolomic profiles were generated detailing metabolite features and biological pathways that are altered in response to mechanical stimulation. In total, 1,457 metabolite features were detected. Statistical analyses identified several pathways of interest. Taken together, differences between experimental groups were associated with inflammatory pathways, lipid metabolism, beta-oxidation, central energy metabolism, and amino acid production. These findings expand our understanding of chondrocyte mechanotransduction under varying loading conditions and time periods.

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Oxidant and antioxidant compounds, gas exchange and growth of young Schizolobium parahyba var. amazonicum plants under high boron and calcium concentrations

Emirates Journal of Food and Agriculture ◽

10.9755/ejfa.2017.v29.i12.1571 ◽

2018 ◽

pp. 994

Author(s):

Daihany Moraes Callegari Elaine M. S. G. Lobato

Keyword(s):

Oxidative Stress ◽

Gas Exchange ◽

Antioxidant Compounds ◽

Total Glutathione ◽

Biochemical Responses ◽

Schizolobium Parahyba ◽

High Boron ◽

High Concentrations ◽

Negative Impacts

Boron (B) and Calcium (Ca) unbalance in plants during early stages can generate oxidative stress and consequently to interfere negatively on growth and quality of seedlings. This study aims to evaluate the gas exchange and measure the biochemical responses, responding how high concentrations of B and Ca can affect the growth and quality of young Schizolobium parahyba plants. The experimental design used was completely randomised with four treatments [1 - 25 µM B + 5 mM Ca (control); 2 - 25 µM B + 50 mM Ca (Ca high); 3- 250 µM B + 5 mM Ca (B high) and 4 - 250 µM B + 50 mM Ca (B and Ca high)]. Negative impacts on gas exchange, photosynthetic pigments and total glutathione were obtained, besides increases in hydrogen peroxide and electrolyte leakage were verified in plants treated with B and Ca high, indicating oxidative stress. Thus, application 250 µM B combined with 50 mM Ca promoted disorders in plant metabolism, decreasing the growth and quality of young Schizolobium parahyba plants.

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The Driving Force: Nuclear Mechanotransduction in Cellular Function, Fate, and Disease

Annual Review of Biomedical Engineering ◽

10.1146/annurev-bioeng-060418-052139 ◽

2019 ◽

Vol 21 (1) ◽

pp. 443-468 ◽

Cited By ~ 31

Author(s):

Melanie Maurer ◽

Jan Lammerding

Keyword(s):

Cell Fate ◽

Conformational Changes ◽

Current Evidence ◽

Mechanical Stimuli ◽

Cellular Behavior ◽

Biochemical Responses ◽

Technological Developments ◽

Transcriptional Changes ◽

Partial Unfolding ◽

New Treatment

Cellular behavior is continuously affected by microenvironmental forces through the process of mechanotransduction, in which mechanical stimuli are rapidly converted to biochemical responses. Mounting evidence suggests that the nucleus itself is a mechanoresponsive element, reacting to cytoskeletal forces and mediating downstream biochemical responses. The nucleus responds through a host of mechanisms, including partial unfolding, conformational changes, and phosphorylation of nuclear envelope proteins; modulation of nuclear import/export; and altered chromatin organization, resulting in transcriptional changes. It is unclear which of these events present direct mechanotransduction processes and which are downstream of other mechanotransduction pathways. We critically review and discuss the current evidence for nuclear mechanotransduction, particularly in the context of stem cell fate, a largely unexplored topic, and in disease, where an improved understanding of nuclear mechanotransduction is beginning to open new treatment avenues. Finally, we discuss innovative technological developments that will allow outstanding questions in the rapidly growing field of nuclear mechanotransduction to be answered.

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The plasma membrane as a mechanochemical transducer

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2018.0221 ◽

2019 ◽

Vol 374 (1779) ◽

pp. 20180221 ◽

Cited By ~ 24

Author(s):

Anabel-Lise Le Roux ◽

Xarxa Quiroga ◽

Nikhil Walani ◽

Marino Arroyo ◽

Pere Roca-Cusachs

Keyword(s):

Plasma Membrane ◽

Cellular Response ◽

Mechanical Response ◽

Membrane Curvature ◽

Mechanical Stresses ◽

Mechanical Stimuli ◽

Biochemical Responses ◽

Interdisciplinary Approaches ◽

Mechanochemical Transduction

Cells are constantly submitted to external mechanical stresses, which they must withstand and respond to. By forming a physical boundary between cells and their environment that is also a biochemical platform, the plasma membrane (PM) is a key interface mediating both cellular response to mechanical stimuli, and subsequent biochemical responses. Here, we review the role of the PM as a mechanosensing structure. We first analyse how the PM responds to mechanical stresses, and then discuss how this mechanical response triggers downstream biochemical responses. The molecular players involved in PM mechanochemical transduction include sensors of membrane unfolding, membrane tension, membrane curvature or membrane domain rearrangement. These sensors trigger signalling cascades fundamental both in healthy scenarios and in diseases such as cancer, which cells harness to maintain integrity, keep or restore homeostasis and adapt to their external environment. This article is part of a discussion meeting issue ‘Forces in cancer: interdisciplinary approaches in tumour mechanobiology’.

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Radix Sophorae flavescentis for Chronic Hepatitis B: A Systematic Review of Randomized Trials

The American Journal of Chinese Medicine ◽

10.1142/s0192415x03001107 ◽

2003 ◽

Vol 31 (03) ◽

pp. 337-354 ◽

Cited By ~ 66

Author(s):

Jianping Liu ◽

Minghui Zhu ◽

Rui Shi ◽

Min Yang

Keyword(s):

Systematic Review ◽

Chronic Hepatitis ◽

Hepatitis B ◽

Antiviral Activity ◽

Chronic Hepatitis B ◽

Methodological Quality ◽

Randomized Trials ◽

Specific Treatment ◽

Biochemical Responses

To evaluate the effects of radix Sophorae flavescentis for chronic hepatitis B, a systematic review of randomized clinical trials was conducted. Randomized trials comparing extract of radix Sophorae flavescentis versus placebo, no intervention, non-specific treatment, other active medicines, or interferon for chronic hepatitis B were identified by electronic and manual searches. Trials of Sophorae herb plus other drugs versus other drugs alone were also included. No blinding and language limitations were applied. The methodological quality of trials was assessed by the Jadad scale plus allocation concealment. Meta-analysis was performed where data was available. Twenty-two randomized trials (n = 2409) were included. Methodological quality of the trials was generally low. The combined results showed that matrine (aqueous extract of Sophorae flavescentis) had antiviral activity, positive liver biochemical effects, and improved symptoms and signs compared with non-specific treatment and other herbal medicines. The combination of matrine and interferon-α (IFN-α), thymosin, or basic treatment showed better effects on viral and liver biochemical responses. The antiviral and biochemical responses were not significantly different between matrine and IFN-α. No serious adverse event was reported. Based on the review, Sophorae flavescentis extract (matrine) may have antiviral activity and positive effects on liver biochemistry in chronic hepatitis B. However, the evidence is not sufficient to recommend matrine for routine clinical use due to the generally low methodological quality of the studies. Further rigorous trials are needed.

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Strains in Stratified Agarose Constructs as Determined by Displacement-Encoded MRI

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80143 ◽

2012 ◽

Author(s):

Adam Griebel ◽

C. C. van Donkelaar ◽

Corey P. Neu

Keyword(s):

Tissue Engineering ◽

Cartilage Tissue Engineering ◽

Cartilage Tissue ◽

Mechanical Stimuli ◽

Healthy Cartilage ◽

Mechanical Quality ◽

Different Strains ◽

Engineered Cartilage ◽

External Stimuli

Osteoarthritis (OA) is a debilitating disease for which no satisfactory treatment exists. Tissue engineering-based strategies have shown considerable potential for repair. Agarose is frequently used as a scaffold material, as chondrocytes maintain their phenotype and cells remain responsive to mechanical stimuli. To improve the mechanical quality of tissue engineered cartilage, recent studies aimed to reproduce the depth-dependent structure of healthy cartilage. One approach to achieve this is by applying depth-dependent mechanical stimuli via cyclically sliding a glass cylinder over the cell-seeded agarose construct [1,2]. The different strains applied to the surface and the deeper regions are expected to induce stratified matrix synthesis and therefore stratified tissue stiffness. Consequently, with the same external stimuli, the internal strain distribution may alter with ongoing tissue development. Such effect is important to understand in order to optimize mechanical loading regimes for cartilage tissue engineering.

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Local Shear Deformation in Whole Cartilage Explants Determined by Texture Correlation

ASME 2011 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2011-53496 ◽

2011 ◽

Author(s):

Jonathan T. Henderson ◽

Garrett Shannon ◽

Kai Yuen ◽

Corey P. Neu

Keyword(s):

The United States ◽

Cartilage Explants ◽

Mechanical Stimuli ◽

Cartilage Homeostasis ◽

Cellular Mechanotransduction ◽

Wear And Tear ◽

Prevalent Disease ◽

Local Shear ◽

Mechanical Factors ◽

Shear Strains

Osteoarthritis (OA) is a prevalent disease, afflicting 27 million people in the United States alone [1]. OA is commonly thought of as “wear and tear” of the joints caused by repeated compression and shear strains. The mechanical contribution to the onset and progression of OA is unknown; however, it is likely a result of an imbalance of cartilage homeostasis, represented by a shift in biochemical and mechanical factors that typically maintain healthy joints [2]. Cartilage homeostasis results in part from cellular mechanotransduction events, i.e. the conversion of mechanical stimuli into a biochemical response.

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Direct measurement of TRPV4 and PIEZO1 activity reveals multiple mechanotransduction pathways in chondrocytes

eLife ◽

10.7554/elife.21074 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 67

Author(s):

M Rocio Servin-Vences ◽

Mirko Moroni ◽

Gary R Lewin ◽

Kate Poole

Keyword(s):

High Speed ◽

Direct Evidence ◽

Mechanical Stimuli ◽

Functional Importance ◽

Mechanical Loads ◽

Mechanoelectrical Transduction ◽

Cartilage Homeostasis ◽

Cell Substrate ◽

Pillar Arrays ◽

Current Activation

The joints of mammals are lined with cartilage, comprised of individual chondrocytes embedded in a specialized extracellular matrix. Chondrocytes experience a complex mechanical environment and respond to changing mechanical loads in order to maintain cartilage homeostasis. It has been proposed that mechanically gated ion channels are of functional importance in chondrocyte mechanotransduction; however, direct evidence of mechanical current activation in these cells has been lacking. We have used high-speed pressure clamp and elastomeric pillar arrays to apply distinct mechanical stimuli to primary murine chondrocytes, stretch of the membrane and deflection of cell-substrate contacts points, respectively. Both TRPV4 and PIEZO1 channels contribute to currents activated by stimuli applied at cell-substrate contacts but only PIEZO1 mediates stretch-activated currents. These data demonstrate that there are separate, but overlapping, mechanoelectrical transduction pathways in chondrocytes.

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Image Enhancement by Frequency Analysis

MATEC Web of Conferences ◽

10.1051/matecconf/201822802008 ◽

2018 ◽

Vol 228 ◽

pp. 02008

Author(s):

Chen Yao ◽

Yan Xia ◽

Jiamin Zhu

Keyword(s):

Image Enhancement ◽

Frequency Analysis ◽

Linear Mapping ◽

Experimental Results ◽

Image Mapping ◽

Enhancement Factors ◽

Central Energy ◽

Enhancement Algorithm

Because of lighting or the quality of CMOS/CCD, poor images are often gained, which greatly affect subjective observation. Image enhancement can improve the contrast of poor image. In our paper, we propose a new image enhancement algorithm based on frequency analysis. A central energy of FFT is utilized for computation of image enhancement factors. A linear mapping is used for image mapping. Finally, some experimental results are shown for illustration of our algorithm advantage.

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Using Human Computation to Assist Biologically Inspired Design: Evaluating a Game-With-a-Purpose

Volume 7: 2nd Biennial International Conference on Dynamics for Design; 26th International Conference on Design Theory and Methodology ◽

10.1115/detc2014-34796 ◽

2014 ◽

Author(s):

Ryan Arlitt ◽

Friederich Berthelsdorf ◽

Sebastian Immel ◽

Robert Stone

Keyword(s):

Game Design ◽

Human Computation ◽

Human Reasoning ◽

Online Game ◽

Biological Phenomenon ◽

Biologically Inspired ◽

Biological Phenomena ◽

Promising Solution ◽

Biologically Inspired Design

Locating relevant biological analogies is a challenge that lies at the heart of practicing biologically inspired design. One promising solution involves computationally providing relevant inspiration to the designer. This paper presents a novel human computation game for collecting computable descriptions of biological strategies, an assessment of the quality of these descriptions gathered from experimental data, and an evaluation of the game’s user experience. This human computation approach to collecting and organizing biological phenomena improves upon the breadth of curated database approaches without sacrificing the accuracy afforded by human reasoning skills. The Biology Phenomenon Categorizer (BioP-C); a cooperative, asymmetric, online game; was deployed in a small engineering graduate class in order to collect assertions about the biological phenomenon of cell division. Through the course of playing, the students formed assertions describing key concepts in the passage. These assertions are assessed for their factual correctness, and these correctness ratings are used to identify directly measurable indicators of assertion truth. Areas for improved game design are also identified.

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