scholarly journals Programmed mechano-chemical coupling in reaction-diffusion active matter

2021 ◽  
Author(s):  
Anis Senoussi ◽  
Jean-Christophe Galas ◽  
André Estevez-Torres
Keyword(s):  
Enzyme Reaction ◽  
Reaction Diffusion ◽  
Reaction Networks ◽  
Active Matter ◽  
C Elegans ◽  
Polarization Mechanism ◽  
Chemical Coupling ◽  
Pattern Forming ◽  
Key Aspects

AbstractEmbryo morphogenesis involves a complex combination of pattern-forming mechanisms. However, classical in vitro patterning experiments explore only one mechanism at a time, thus missing coupling effects. Here, we conjugate two major pattern-forming mechanisms —reaction-diffusion and active matter— by integrating dissipative DNA/enzyme reaction networks within an active gel composed of cytoskeletal motors and filaments. We show that the strength of the flow generated by the active gel controls the mechano-chemical coupling between the two subsystems. We use this property to engineer the mechanical activation of chemical reaction networks both in time and space, thus mimicking key aspects of the polarization mechanism observed in C. elegans oocytes. We anticipate that reaction-diffusion active matter may be useful to investigate mechano-chemical transduction and to design new materials with life-like properties.

scholarly journals Programmed mechano-chemical coupling in reaction-diffusion active matter

2021 ◽  
Vol 7 (51) ◽  
Author(s):  
Anis Senoussi ◽  
Jean-Christophe Galas ◽  
André Estevez-Torres
Keyword(s):  
Reaction Diffusion ◽  
Active Matter ◽  
Chemical Coupling

Investigation of the effect of loratadine and calcium ions on oxidoreductase activity of catalase enzyme

2020 ◽  
Vol 16 ◽  
Author(s):  
Edhem Hasković ◽  
Safija Herenda ◽  
Zehra Halilović ◽  
Snežana Unčanin ◽  
Denis Hasković ◽  
...  
Keyword(s):  
Calcium Ions ◽  
Enzyme Reaction ◽  
Analytical Techniques ◽  
Competitive Inhibitor ◽  
Cellular Functions ◽  
Oxidoreductase Activity ◽  
H1 Antihistamines ◽  
Activity Of Enzymes ◽  
The Given

Background: The Spectrophotometric method is one of the most suitable analytical techniques for testing the activity of enzymes under the influence of various factors. Methods: The effect of H1-antihistamines of loratadine and calcium ions on enzyme catalase under in vitro conditions was investigated in this paper. Results and Discussion: It has been shown that loratadine isa partial inhibitor of catalase, but this effect is diminished in the presence of calcium ions. Calcium as well as other cations are important for many biological and cellular functions. The kidneys play a central role in the homeostasis of these ions. The activity of the catalase enzyme under the given conditions, the type of inhibition,and the kinetic parameters of the enzyme reaction were determined. Conclusion: We concluded that loratadine is a partially competitive inhibitor.

Streblus asper Lour. exerts MAPK and SKN-1 mediated anti-aging, anti-photoaging activities and imparts neuroprotection by ameliorating Aβ in Caenorhabditis elegans

2021 ◽  
pp. 1-17
Author(s):  
Mani Iyer Prasanth ◽  
James Michael Brimson ◽  
Dicson Sheeja Malar ◽  
Anchalee Prasansuklab ◽  
Tewin Tencomnao
Keyword(s):  
Oxidative Stress ◽  
Caenorhabditis Elegans ◽  
Stress Resistance ◽  
Vital Role ◽  
Transgenic Strain ◽  
Wild Type ◽  
Neuroprotective Effects ◽  
C Elegans ◽  
Streblus Asper

BACKGROUND: Streblus asper Lour., has been reported to have anti-aging and neuroprotective efficacies in vitro. OBJECTIVE: To analyze the anti-aging, anti-photoaging and neuroprotective efficacies of S. asper in Caenorhabditis elegans. METHODS: C. elegans (wild type and gene specific mutants) were treated with S. asper extract and analyzed for lifespan and other health benefits through physiological assays, fluorescence microscopy, qPCR and Western blot. RESULTS: The plant extract was found to increase the lifespan, reduce the accumulation of lipofuscin and modulate the expression of candidate genes. It could extend the lifespan of both daf-16 and daf-2 mutants whereas the pmk-1 mutant showed no effect. The activation of skn-1 was observed in skn-1::GFP transgenic strain and in qPCR expression. Further, the extract can extend the lifespan of UV-A exposed nematodes along with reducing ROS levels. Additionally, the extract also extends lifespan and reduces paralysis in Aβ transgenic strain, apart from reducing Aβ expression. CONCLUSIONS: S. asper was able to extend the lifespan and healthspan of C. elegans which was independent of DAF-16 pathway but dependent on SKN-1 and MAPK which could play a vital role in eliciting the anti-aging, anti-photoaging and neuroprotective effects, as the extract could impart oxidative stress resistance and neuroprotection.

scholarly journals LRIG1 is a conserved EGFR regulator involved in melanoma development, survival and treatment resistance

Oncogene ◽  
2021 ◽  
Author(s):  
Ola Billing ◽  
Ylva Holmgren ◽  
Daniel Nosek ◽  
Håkan Hedman ◽  
Oskar Hemmingsson
Keyword(s):  
Growth Factor Receptor ◽  
Braf Inhibitor ◽  
Treatment Resistance ◽  
Negative Regulator ◽  
C Elegans ◽  
Rtk Signaling ◽  
Egfr Expression ◽  
Inhibitor Resistance ◽  
Leucine Rich Repeats

AbstractLeucine-rich repeats and immunoglobulin-like domains 1 (LRIG1) is a pan-negative regulator of receptor tyrosine kinase (RTK) signaling and a tumor suppressor in several cancers, but its involvement in melanoma is largely unexplored. Here, we aim to determine the role of LRIG1 in melanoma tumorigenesis, RTK signaling, and BRAF inhibitor resistance. We find that LRIG1 is downregulated during early tumorigenesis and that LRIG1 affects activation of the epidermal growth factor receptor (EGFR) in melanoma cells. LRIG1-dependent regulation of EGFR signaling is evolutionary conserved to the roundworm C. elegans, where negative regulation of the EGFR-Ras-Raf pathway by sma-10/LRIG completely depends on presence of the receptor let-23/EGFR. In a cohort of metastatic melanoma patients, we observe an association between LRIG1 and survival in the triple wild-type subtype and in tumors with high EGFR expression. During in vitro development of BRAF inhibitor resistance, LRIG1 expression decreases; and mimics LRIG1 knockout cells for increased EGFR expression. Treating resistant cells with recombinant LRIG1 suppresses AKT activation and proliferation. Together, our results show that sma-10/LRIG is a conserved regulator of RTK signaling, add to our understanding of LRIG1 in melanoma and identifies recombinant LRIG1 as a potential therapeutic against BRAF inhibitor-resistant melanoma.

scholarly journals Nutricosmetic effects of Asparagus officinalis: a potent matrix metalloproteinase-1 inhibitor

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Suwannee Sriyab ◽  
Nachtharinee Laosirisathian ◽  
Chanun Punyoyai ◽  
Songyot Anuchapreeda ◽  
Singkome Tima ◽  
...  
Keyword(s):  
Matrix Metalloproteinase ◽  
Antioxidant Activities ◽  
Epigallocatechin Gallate ◽  
Enzyme Reaction ◽  
Asparagus Officinalis ◽  
Peripheral Blood Mononuclear ◽  
Antioxidant Power ◽  
Matrix Metalloproteinase 1 ◽  
Ferric Reducing Antioxidant Power

AbstractThis study aimed to investigate the nutricosmetic effect of Asparagus officinalis extracts. The tip and spear of A. officinalis were successively extracted with 95% ethanol. The rutin, phenolic, and flavonoid contents of A. officinalis extracts were investigated. The antioxidant activities were determined by 2,2-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) and a ferric reducing antioxidant power assay. Matrix metalloproteinase-1 (MMP-1), elastase, and hyaluronidase inhibition were determined by in vitro enzyme reaction assay. The cytotoxicity was analyzed on peripheral blood mononuclear cellss. Findings revealed that drying temperature and drying duration had significant effects on the chemical composition and biological activity of A. officinalis extract. A. officinalis tips dried at 50 °C for 24 h contained the (significantly) highest flavonoid and rutin content. The most potent extract was from A. officinalis spears since it possessed the (significantly) highest MMP-1, elastase, and hyaluronidase inhibition rates of 83.4 ± 1.5%, 70.4 ± 4.1%, and 75.2 ± 1.0%, respectively. Interestingly, at the same concentration, the A. officinalis spear extract was more potent in MMP-1 inhibition than oleanolic acid and epigallocatechin gallate, the well-known natural MMP-1 inhibitors. The results show that A. officinalis extract is an attractive source of natural anti-skin-wrinkle ingredients.

scholarly journals The double-stranded DNA-binding proteins TEBP-1 and TEBP-2 form a telomeric complex with POT-1

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Sabrina Dietz ◽  
Miguel Vasconcelos Almeida ◽  
Emily Nischwitz ◽  
Jan Schreier ◽  
Nikenza Viceconte ◽  
...  
Keyword(s):  
Quantitative Proteomics ◽  
Wild Type ◽  
C Elegans ◽  
Double Stranded Dna ◽  
Telomere Sequence ◽  
Proteomics Approach ◽  
Telomeric Protein ◽  
Regulate Telomere Length

AbstractTelomeres are bound by dedicated proteins, which protect them from DNA damage and regulate telomere length homeostasis. In the nematode Caenorhabditis elegans, a comprehensive understanding of the proteins interacting with the telomere sequence is lacking. Here, we harnessed a quantitative proteomics approach to identify TEBP-1 and TEBP-2, two paralogs expressed in the germline and embryogenesis that associate to telomeres in vitro and in vivo. tebp-1 and tebp-2 mutants display strikingly distinct phenotypes: tebp-1 mutants have longer telomeres than wild-type animals, while tebp-2 mutants display shorter telomeres and a Mortal Germline. Notably, tebp-1;tebp-2 double mutant animals have synthetic sterility, with germlines showing signs of severe mitotic and meiotic arrest. Furthermore, we show that POT-1 forms a telomeric complex with TEBP-1 and TEBP-2, which bridges TEBP-1/-2 with POT-2/MRT-1. These results provide insights into the composition and organization of a telomeric protein complex in C. elegans.

scholarly journals In Vitro and In Silico Characterization of an Antimalarial Compound with Antitumor Activity Targeting Human DNA Topoisomerase IB

2021 ◽  
Vol 22 (14) ◽  
pp. 7455
Author(s):  
Bini Chhetri Soren ◽  
Jagadish Babu Dasari ◽  
Alessio Ottaviani ◽  
Beatrice Messina ◽  
Giada Andreotti ◽  
...  
Keyword(s):  
Enzyme Reaction ◽  
Dna Topoisomerase ◽  
Human Dna ◽  
Topoisomerase Ib ◽  
Topological State ◽  
Cleavage Step ◽  
Dynamics Simulations ◽  
In Silico Characterization ◽  
Dna Complex

Human DNA topoisomerase IB controls the topological state of supercoiled DNA through a complex catalytic cycle that consists of cleavage and religation reactions, allowing the progression of fundamental DNA metabolism. The catalytic steps of human DNA topoisomerase IB were analyzed in the presence of a drug, obtained by the open-access drug bank Medicines for Malaria Venture. The experiments indicate that the compound strongly and irreversibly inhibits the cleavage step of the enzyme reaction and reduces the cell viability of three different cancer cell lines. Molecular docking and molecular dynamics simulations suggest that the drug binds to the human DNA topoisomerase IB-DNA complex sitting inside the catalytic site of the enzyme, providing a molecular explanation for the cleavage-inhibition effect. For all these reasons, the aforementioned drug could be a possible lead compound for the development of an efficient anti-tumor molecule targeting human DNA topoisomerase IB.

scholarly journals Caenorhabditis elegans as an in vivo Model to Assess Amphetamine Tolerance

2021 ◽  
pp. 1-9
Author(s):  
Dayana Torres Valladares ◽  
Sirisha Kudumala ◽  
Murad Hossain ◽  
Lucia Carvelli
Keyword(s):  
Caenorhabditis Elegans ◽  
Molecular Mechanisms ◽  
Drugs Of Abuse ◽  
Genetic Model ◽  
In Vivo Model ◽  
C Elegans ◽  
Hyperactivity Disorder ◽  
In Vitro Data

Amphetamine is a potent psychostimulant also used to treat attention deficit/hyperactivity disorder and narcolepsy. In vivo and in vitro data have demonstrated that amphetamine increases the amount of extra synaptic dopamine by both inhibiting reuptake and promoting efflux of dopamine through the dopamine transporter. Previous studies have shown that chronic use of amphetamine causes tolerance to the drug. Thus, since the molecular mechanisms underlying tolerance to amphetamine are still unknown, an animal model to identify the neurochemical mechanisms associated with drug tolerance is greatly needed. Here we took advantage of a unique behavior caused by amphetamine in <i>Caenorhabditis elegans</i> to investigate whether this simple, but powerful, genetic model develops tolerance following repeated exposure to amphetamine. We found that at least 3 treatments with 0.5 mM amphetamine were necessary to see a reduction in the amphetamine-induced behavior and, thus, to promote tolerance. Moreover, we found that, after intervals of 60/90 minutes between treatments, animals were more likely to exhibit tolerance than animals that underwent 10-minute intervals between treatments. Taken together, our results show that <i>C. elegans</i> is a suitable system to study tolerance to drugs of abuse such as amphetamines.

scholarly journals Experimental Models for Studying HPV-Positive and HPV-Negative Penile Cancer: New Tools for An Old Disease

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 460
Author(s):  
Beatriz Medeiros-Fonseca ◽  
Antonio Cubilla ◽  
Haissa Brito ◽  
Tânia Martins ◽  
Rui Medeiros ◽  
...  
Keyword(s):  
Mouse Models ◽  
Cell Lines ◽  
Penile Cancer ◽  
Hpv Infection ◽  
Experimental Models ◽  
In Vivo Models ◽  
Recent Developments ◽  
Key Aspects

Penile cancer is an uncommon malignancy that occurs most frequently in developing countries. Two pathways for penile carcinogenesis are currently recognized: one driven by human papillomavirus (HPV) infection and another HPV-independent route, associated with chronic inflammation. Progress on the clinical management of this disease has been slow, partly due to the lack of preclinical models for translational research. However, exciting recent developments are changing this landscape, with new in vitro and in vivo models becoming available. These include mouse models for HPV+ and HPV− penile cancer and multiple cell lines representing HPV− lesions. The present review addresses these new advances, summarizing available models, comparing their characteristics and potential uses and discussing areas that require further improvement. Recent breakthroughs achieved using these models are also discussed, particularly those developments pertaining to HPV-driven cancer. Two key aspects that still require improvement are the establishment of cell lines that can represent HPV+ penile carcinomas and the development of mouse models to study metastatic disease. Overall, the growing array of in vitro and in vivo models for penile cancer provides new and useful tools for researchers in the field and is expected to accelerate pre-clinical research on this disease.

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