scholarly journals Does SARS-CoV-2 Trigger Stress-Induced Autoimmunity by Molecular Mimicry? A Hypothesis

2020 ◽  
Vol 9 (7) ◽  
pp. 2038 ◽  
Author(s):  
Francesco Cappello ◽  
Antonella Marino Gammazza ◽  
Francesco Dieli ◽  
Everly Conway de Macario ◽  
Alberto JL Macario
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Molecular Mimicry ◽  
Short Review ◽  
Working Hypothesis ◽  
In Vivo Tests ◽  
Autoimmune Phenomena ◽  
Effective Treatments

Viruses can generate molecular mimicry phenomena within their hosts. Why should severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) not be considered one of these? Information in this short review suggests that it might be so and, thus, encourages research aiming at testing this possibility. We propose, as a working hypothesis, that the virus induces antibodies and that some of them crossreact with host’s antigens, thus eliciting autoimmune phenomena with devasting consequences in various tissues and organs. If confirmed, by in vitro and in vivo tests, this could drive researchers to find effective treatments against the virus.

scholarly journals Plant-Derived Secondary Metabolites as Potential Mediators against COVID-19: A Review

2020 ◽  
pp. 1-18
Author(s):  
Lekha Nath Khanal ◽  
Yuba Raj Pokharel ◽  
Khagaraj Sharma ◽  
Surya Kanta Kalauni
Keyword(s):  
Secondary Metabolites ◽  
Severe Acute Respiratory Syndrome ◽  
Health Concern ◽  
Traditional Herbal Medicine ◽  
Research Papers ◽  
Treatment Regimes ◽  
Pubmed Database ◽  
In Vivo Tests

The current pandemic of COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has envisioned a global health concern. The scientists and physicians around the world have been racing to understand the pathophysiology and possible treatment régimes to discover an effective therapeutic resolution against the disease. Different secondary metabolites from plants exhibit substantial biological assets including antiviral activity. These compounds may be used against the infections of coronavirus. The research papers, reviews, and preprints were searched from the PubMed database using keywords like severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome (MERS), and traditional herbal medicine against COVID-19. The review focuses on those natural products which exhibited optimistic results against SARS-COV and SARS-CoV-2 in virtual as well as physical in vitro and in vivo tests. It summarizes the epidemiological characters, pathogenesis, structure, and targeting strategies of the virus. The compounds like lycorine, psoralidin, quercetin, glycyrrhizin, baicalin, caffeic acid, etc. could be the leads for the drug development against COVID-19.  

scholarly journals Effects of Bacterial CLPB Protein Fragments on Food Intake and PYY Secretion

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2223
Author(s):  
Manon Dominique ◽  
Nicolas Lucas ◽  
Romain Legrand ◽  
Illona-Marie Bouleté ◽  
Christine Bôle-Feysot ◽  
...  
Keyword(s):  
Food Intake ◽  
Peptide Yy ◽  
Molecular Mimicry ◽  
Potential Effect ◽  
In Vivo Studies ◽  
Sprague Dawley ◽  
E Coli ◽  
In Vivo Effects

CLPB (Caseinolytic peptidase B) protein is a conformational mimetic of α-MSH, an anorectic hormone. Previous in vivo studies have already shown the potential effect of CLPB protein on food intake and on the production of peptide YY (PYY) by injection of E. coli wild type (WT) or E. coli ΔClpB. However, until now, no study has shown its direct effect on food intake. Furthermore, this protein can fragment naturally. Therefore, the aim of this study was (i) to evaluate the in vitro effects of CLPB fragments on PYY production; and (ii) to test the in vivo effects of a CLPB fragment sharing molecular mimicry with α-MSH (CLPB25) compared to natural fragments of the CLPB protein (CLPB96). To do that, a primary culture of intestinal mucosal cells from male Sprague–Dawley rats was incubated with proteins extracted from E. coli WT and ΔCLPB after fragmentation with trypsin or after a heat treatment of the CLPB protein. PYY secretion was measured by ELISA. CLPB fragments were analyzed by Western Blot using anti-α-MSH antibodies. In vivo effects of the CLPB protein on food intake were evaluated by intraperitoneal injections in male C57Bl/6 and ob/ob mice using the BioDAQ® system. The natural CLPB96 fragmentation increased PYY production in vitro and significantly decreased cumulative food intake from 2 h in C57Bl/6 and ob/ob mice on the contrary to CLPB25. Therefore, the anorexigenic effect of CLPB is likely the consequence of enhanced PYY secretion.

In Vitro Methods as a Tool in Neurotoxicity Studies

1995 ◽  
Vol 23 (4) ◽  
pp. 491-496
Author(s):  
Hanna Tähti ◽  
Leila Vaalavirta ◽  
Tarja Toimela
Keyword(s):  
Risk Evaluation ◽  
Toxicity Testing ◽  
In Vitro Models ◽  
In Vitro Tests ◽  
Industrial Chemicals ◽  
Mercury Compounds ◽  
Toxicological Data ◽  
In Vivo Tests

— There are several hundred industrial chemicals with neurotoxic potential. The neurotoxic risks of most of these chemicals are unknown. Additional methods are needed to assess the risks more effectively and to elucidate the mechanisms of neurotoxicity more accurately than is possible with the conventional methods. This paper deals with general tasks concerning the use of in vitro models in the evaluation of neurotoxic risks. It is based on our previous studies with various in vitro models and on recent literature. The induction of glial fibrillary acidic protein in astrocyte cultures after treatment with known neurotoxicants (mercury compounds and aluminium) is discussed in more detail as an important response which can be detected in vitro. When used appropriately with in vivo tests and with previous toxicological data, in vitro neurotoxicity testing considerably improves risk assessment. The incorporation of in vitro tests into the early stages of risk evaluation can reduce the number of animals used in routine toxicity testing, by identifying chemicals with high neurotoxic potential.

scholarly journals Role of in vitro and in vivo tests of hypersensitivity in beryllium workers.

1977 ◽  
Vol 30 (1) ◽  
pp. 24-28 ◽  
Author(s):  
C D Price ◽  
W J Williams ◽  
A Pugh ◽  
D H Joynson
Keyword(s):  
In Vivo Tests

scholarly journals Essential Oils and Their Bioactive Compounds in the Control of Gastrointestinal Nematodes of Small Ruminants

2018 ◽  
Vol 46 (1) ◽  
pp. 14 ◽  
Author(s):  
Weibson Paz Pinheiro André ◽  
Wesley Lyeverton Correia Ribeiro ◽  
Lorena Mayana Beserra de Oliveira ◽  
Iara Tersia Freitas Macedo ◽  
Fernanda Cristina Macedo Rondon ◽  
...  
Keyword(s):  
Natural Products ◽  
Essential Oils ◽  
Bioactive Compounds ◽  
Small Ruminant ◽  
Anthelmintic Activity ◽  
Gastrointestinal Nematodes ◽  
In Vivo Tests ◽  
Anthelmintic Effect

Background: Gastrointestinal nematodes are one of the major health and economic problem of sheep and goats in the world. The control of these nematodes is carried out conventionally with synthetic anthelminths, which favored the selection of gastrointestinal nematode (GIN) populations multiresistant to anthelmintics. The emergence of anthelmintic resistance has stimulated the search for new alternatives to control small ruminant GIN, standing out the use of plants and their bioactives compounds, such as essential oils (EO). The objective of this review was to present the main characteristics and anthelmintic activity of EO, their isolated compounds and drug delivery systems in the control of GIN.Review: Essential oils are a complex blend of bioactive compounds with volatile, lipophilic, usually odoriferous and liquid substances. EO are composed of terpenes, terpenoids, aromatic and aliphatic constituents. EO has various pharmacological activities of interest in preventive veterinary medicine such as antibacterials, antifungals, anticoccicids, insecticides and anthelmintics. In vitro and in vivo tests are used to validate the anthelmintic activity of EO on GIN. In vitro tests are low cost screening tests that allow the evaluation of the anthelmintic activity of a large amount of bioactive compounds on eggs, first (L1) and third stage larvae (L3), and adult nematodes. The antiparasitic effect of EO is related to its main compound or to the interaction of the compounds. These bioactive compounds penetrate the cuticle of the nematodes by transcuticular diffusion, altering the mechanisms of locomotion, besides causing cuticular lesions. Following in vitro evaluation, the acute and sub-chronic toxicity test should be performed to assess the toxicity of the bioactive compounds and to define the dose to be used in in vivo tests. In vivo tests are more reliable because the anthelmintic effectiveness of bioactive compounds is evaluated after the metabolization process. The metabolization process of the bioactive compounds can generate metabolites that exhibit or not anthelmintic effectiveness. The in vivo tests assessing the anthelmintic effectiveness of bioactive compounds in sheep and goats are the fecal egg count reduction test and the controlled test.  OE promoted reduction of egg elimination in faeces which may be related to cuticular and reproductive alterations in GIN, and reduction of parasite burden in in vivo tests. Due to the promising results obtained with OE in the in vivo tests, interest has been aroused in using nanotechnology as an alternative to increase the bioavailability of OE and consequently, potentializing its anthelmintic effect, reducing the dose and  toxicity of the biocompounds. In addition to nanotechnology, the isolation and chemical modification of compounds isolated from OE have been employed to obtain new molecules with anthelmintic action and understand the mechanism of action of EO on the small ruminant GIN.Conclusion: The use of EO and their compound bioactive in the control of resistant populations of GIN is a promising alternative. The adoption of strategies in which natural products can replace synthetic anthelmintics, such as in dry periods and use synthetic anthelmintics in the rainy season when the population in refugia in the pasture is high, thus reducing the dissemination of GIN resistant populations. As perspective, the evaluation of pharmacokinetics and pharmacodynamics of these natural products should be performed so that one defines treatment protocols that optimize the anthelmintic effect.

scholarly journals Murine monoclonal antibodies against RBD of SARS-CoV-2 neutralize authentic wild type SARS-CoV-2 as well as B.1.1.7 and B.1.351 viruses and protect in vivo in a mouse model in a neutralization dependent manner

2021 ◽  
Author(s):  
Fatima Amanat ◽  
Shirin Strohmeier ◽  
Wen-Hsin Lee ◽  
Sandhya Bangaru ◽  
Andrew B Ward ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Severe Acute Respiratory Syndrome ◽  
Mouse Model ◽  
Neutralizing Antibodies ◽  
Dependent Manner ◽  
Receptor Binding Domain ◽  
Wild Type ◽  
Murine Monoclonal Antibodies

After first emerging in December 2019 in China, severe acute respiratory syndrome 2 (SARS-CoV-2) has since caused a pandemic leading to millions of infections and deaths worldwide. Vaccines have been developed and authorized but supply of these vaccines is currently limited. With new variants of the virus now emerging and spreading globally, it is essential to develop therapeutics that are broadly protective and bind conserved epitopes in the receptor binding domain (RBD) or the whole spike of SARS-CoV-2. In this study, we have generated mouse monoclonal antibodies (mAbs) against different epitopes on the RBD and assessed binding and neutralization against authentic SARS-CoV-2. We have demonstrated that antibodies with neutralizing activity, but not non-neutralizing antibodies, lower viral titers in the lungs when administered in a prophylactic setting in vivo in a mouse challenge model. In addition, most of the mAbs cross-neutralize the B.1.351 as well as the B.1.1.7 variants in vitro.

scholarly journals Effects of Curcumin on Vessel Formation Insight into the Pro- and Antiangiogenesis of Curcumin

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Ting-ye Wang ◽  
Jia-xu Chen
Keyword(s):  
Curcuma Longa ◽  
Scientific Evidence ◽  
Short Review ◽  
Dual Effect ◽  
Scientific Databases ◽  
Wide Range ◽  
Available Information ◽  
Insight Into

Curcumin is a compound extracted from the Curcuma longa L, which possesses a wide range of pharmacological effects. However, few studies have collected scientific evidence on its dual effect on angiogenesis. The present review gathered the fragmented information available in the literature to discuss the dual effect and possible mechanisms of curcumin on angiogenesis. Available information concerning the effect of curcumin on angiogenesis is compiled from scientific databases, including PubMed and Web of Science using the key term (curcumin and angiogenesis). The results were reviewed to identify relevant articles. Related literature demonstrated that curcumin has antiangiogenesis effect via regulating multiple factors, including proangiogenesis factor VEGF, MMPs, and FGF, both in vivo and in vitro, and could promote angiogenesis under certain circumstances via these factors. This paper provided a short review on bidirectional action of curcumin, which should be useful for further study and application of this compound that require further studies.

Sign in / Sign up

Export Citation Format

Share Document