Immunotoxic Effects Induced by Microcystins and Cylindrospermopsin: A Review

Cyanotoxin occurrence is gaining importance due to anthropogenic activities, climate change and eutrophication. Among them, Microcystins (MCs) and Cylindrospermopsin (CYN) are the most frequently studied due to their ubiquity and toxicity. Although MCs are primary classified as hepatotoxins and CYN as a cytotoxin, they have been shown to induce deleterious effects in a wide range of organs. However, their effects on the immune system are as yet scarcely investigated. Thus, to know the impact of cyanotoxins on the immune system, due to its importance in organisms’ homeostasis, is considered of interest. A review of the scientific literature dealing with the immunotoxicity of MCs and CYN has been performed, and both in vitro and in vivo studies have been considered. Results have confirmed the scarcity of reports on the topic, particularly for CYN. Decreased cell viability, apoptosis or altered functions of immune cells, and changed levels and mRNA expression of cytokines are among the most common effects reported. Underlying mechanisms, however, are still not yet fully elucidated. Further research is needed in order to have a full picture of cyanotoxin immunotoxicity.

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Pathophysiological Role and Therapeutic Implications of Vitamin D in Autoimmunity: Focus on Chronic Autoimmune Diseases

Nutrients ◽

10.3390/nu12030789 ◽

2020 ◽

Vol 12 (3) ◽

pp. 789 ◽

Cited By ~ 4

Author(s):

Mattia Bellan ◽

Laura Andreoli ◽

Chiara Mele ◽

Pier Paolo Sainaghi ◽

Cristina Rigamonti ◽

...

Keyword(s):

Vitamin D ◽

Immune System ◽

Autoimmune Diseases ◽

Convincing Evidence ◽

In Vivo Studies ◽

Human Immune System ◽

Therapeutic Implications ◽

Wide Range

Vitamin D is a pleiotropic secosteroid yielding multiple actions in human physiology. Besides the canonical regulatory activity on bone metabolism, several non-classical actions have been described and the ability of vitamin D to partake in the regulation of the immune system is particularly interesting, though far stronger and convincing evidence has been collected in in vitro as compared to in vivo studies. Whether vitamin D is able to regulate at physiological concentrations the human immune system remains unproven to date. Consequently, it is not established if vitamin D status is a factor involved in the pathogenesis of immune-mediated diseases and if cholecalciferol supplementation acts as an adjuvant for autoimmune diseases. The development of autoimmunity is a heterogeneous process, which may involve different organs and systems with a wide range of clinical implications. In the present paper, we reviewed the current evidences regarding vitamin D role in the pathogenesis and management of different autoimmune diseases.

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CircFAM13B promotes the proliferation of hepatocellular carcinoma by sponging miR-212, upregulating E2F5 expression and activating the P53 pathway

Cancer Cell International ◽

10.1186/s12935-021-02120-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Ying Xie ◽

Xiaofeng Hang ◽

Wensheng Xu ◽

Jing Gu ◽

Yuanjing Zhang ◽

...

Keyword(s):

Gene Expression ◽

Hepatocellular Carcinoma ◽

Gene Expression Omnibus ◽

Differentially Expressed ◽

In Vivo Studies ◽

Circular Rnas ◽

Novel Target ◽

Underlying Mechanisms

Abstract Background Most of the biological functions of circular RNAs (circRNAs) and the potential underlying mechanisms in hepatocellular carcinoma (HCC) have not yet been discovered. Methods In this study, using circRNA expression data from HCC tumor tissues and adjacent tissues from the Gene Expression Omnibus database, we identified out differentially expressed circRNAs and verified them by qRT-PCT. Functional experiments were performed to evaluate the effects of circFAM13B in HCC in vitro and in vivo. Results We found that circFAM13B was the most significantly differentially expressed circRNA in HCC tissue. Subsequently, in vitro and in vivo studies also demonstrated that circFAM13B promoted the proliferation of HCC. Further studies revealed that circFAM13B, a sponge of miR-212, is involved in the regulation of E2F5 gene expression by competitively binding to miR-212, inhibits the activation of the P53 signalling pathway, and promotes the proliferation of HCC cells. Conclusions Our findings revealed the mechanism underlying the regulatory role played by circFAM13B, miR-212 and E2F5 in HCC. This study provides a new theoretical basis and novel target for the clinical prevention and treatment of HCC.

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67 Current Status and Future Prospective of the Use of Plant Bioactive Compounds in Dairy and Beef Cattle

Journal of Animal Science ◽

10.1093/jas/skab054.222 ◽

2021 ◽

Vol 99 (Supplement_1) ◽

pp. 132-132

Author(s):

Sergio Calsamiglia ◽

Maria Rodriguez-Prado ◽

Gonzalo Fernandez-Turren ◽

Lorena Castillejos

Keyword(s):

Beef Cattle ◽

Essential Oils ◽

Average Daily Gain ◽

Rumen Fermentation ◽

Production Performance ◽

In Vivo Studies ◽

Current Status ◽

The Impact

Abstract In the last 20 years there has been extensive in vitro research on the effects of plant extracts and essential oils on rumen microbial fermentation. The main objectives have been to improve energy metabolism through a reduction in methane emissions and an increase in propionate production; and to improve protein metabolism by reducing proteolysis and deamination. While the positive results from in vitro studies has stimulated the release of commercial products based on blends of essential oils, there is limited in vivo evidence on the rumen fermentation and production performance effects. A literature search was conducted to select in vivo studies where information on rumen fermentation and animal performance was reported. For dairy cattle, we identified 37 studies of which 21 were adequate to test production performance. Ten studies reported increases and 3 decreases in milk yield. For beef cattle, we identified 20 studies with rumen fermentation profile and 22 with performance data. Average daily gain improved in 7 and decreased in 1 study. Only 1 out of 16 studies reported an improvement in feed efficiency. Data indicate that out of more than 500 products tested in vitro, only around 20 have been tested in vivo in different mixtures and doses. The use of statistical approaches will allow to describe the conditions, doses and responses in dairy and beef cattle performance. The search for postruminal effects offers another alternative use. Evidence for effects on the intestinal and systemic effects on the immune system and antioxidant status (i.e., capsicum, garlic, eugenol, cinnamaldehyde curcuma, catechins, anethol or pinene), and in the modulation of metabolic regulation (capsicum, cinnamaldehyde, curcuma or garlic) may open the opportunity for future applications. However, stability of the product in the GI tract, description of the mechanisms of action and the impact of these changes on performance needs to be further demonstrated.

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Phytochemistry and Pharmacology of the Genus Pedicularis Used in Traditional Chinese Medicine

The American Journal of Chinese Medicine ◽

10.1142/s0192415x14500670 ◽

2014 ◽

Vol 42 (05) ◽

pp. 1071-1098 ◽

Cited By ~ 13

Author(s):

Mao-Xing Li ◽

Xi-Rui He ◽

Rui Tao ◽

Xinyuan Cao

Keyword(s):

Chinese Medicine ◽

Traditional Chinese Medicine ◽

Chemical Constituents ◽

Iridoid Glycosides ◽

In Vivo Studies ◽

Chemical Components ◽

Wide Range ◽

Phenylpropanoid Glycosides

In the present review, the literature data on the chemical constituents and biological investigations of the genus Pedicularis are summarized. Some species of Pedicularis have been widely applied in traditional Chinese medicine. A wide range of chemical components including iridoid glycosides, phenylpropanoid glycosides (PhGs), lignans glycosides, flavonoids, alkaloids and other compounds have been isolated and identified from the genus Pedicularis. In vitro and in vivo studies indicated some monomer compounds and extracts from the genus Pedicularis have been found to possess antitumor, hepatoprotective, anti-oxidative, antihaemolysis, antibacterial activity, fatigue relief of skeletal muscle, nootropic effect and other activities.

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In VivoEfficacy of Anuran Trypsin Inhibitory Peptides against Staphylococcal Skin Infection and the Impact of Peptide Cyclization

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.04324-14 ◽

2015 ◽

Vol 59 (4) ◽

pp. 2113-2121 ◽

Cited By ~ 9

Author(s):

U. Malik ◽

O. N. Silva ◽

I. C. M. Fensterseifer ◽

L. Y. Chan ◽

R. J. Clark ◽

...

Keyword(s):

Antimicrobial Agents ◽

Cyclic Peptide ◽

Sequence Similarity ◽

Infection Model ◽

Content Type ◽

Wide Range ◽

Inhibitory Activities ◽

The Impact

ABSTRACTStaphylococcus aureusis a virulent pathogen that is responsible for a wide range of superficial and invasive infections. Its resistance to existing antimicrobial drugs is a global problem, and the development of novel antimicrobial agents is crucial. Antimicrobial peptides from natural resources offer potential as new treatments against staphylococcal infections. In the current study, we have examined the antimicrobial properties of peptides isolated from anuran skin secretions and cyclized synthetic analogues of these peptides. The structures of the peptides were elucidated by nuclear magnetic resonance (NMR) spectroscopy, revealing high structural and sequence similarity with each other and with sunflower trypsin inhibitor 1 (SFTI-1). SFTI-1 is an ultrastable cyclic peptide isolated from sunflower seeds that has subnanomolar trypsin inhibitory activity, and this scaffold offers pharmaceutically relevant characteristics. The five anuran peptides were nonhemolytic and noncytotoxic and had trypsin inhibitory activities similar to that of SFTI-1. They demonstrated weakin vitroinhibitory activities againstS. aureus, but several had strong antibacterial activities againstS. aureusin anin vivomurine wound infection model. pYR, an immunomodulatory peptide fromRana sevosa, was the most potent, with complete bacterial clearance at 3 mg · kg−1. Cyclization of the peptides improved their stability but was associated with a concomitant decrease in antimicrobial activity. In summary, these anuran peptides are promising as novel therapeutic agents for treating infections from a clinically resistant pathogen.

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Impact of the Order of Initiation of Fluconazole and Amphotericin B in Sequential or Combination Therapy on Killing of Candida albicans In Vitro and in a Rabbit Model of Endocarditis and Pyelonephritis

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.45.2.485-494.2001 ◽

2001 ◽

Vol 45 (2) ◽

pp. 485-494 ◽

Cited By ~ 40

Author(s):

Arnold Louie ◽

Pamela Kaw ◽

Partha Banerjee ◽

Weiguo Liu ◽

George Chen ◽

...

Keyword(s):

Candida Albicans ◽

Amphotericin B ◽

Induced Resistance ◽

Rabbit Model ◽

In Vivo Studies ◽

Infection Model ◽

Simultaneous Exposure ◽

The Impact

ABSTRACT In vitro time-kill studies and a rabbit model of endocarditis and pyelonephritis were used to define the impact that the order of exposure of Candida albicans to fluconazole (FLC) and amphotericin B (AMB), as sequential and combination therapies, had on the susceptibility of C. albicans to AMB and on the outcome. The contribution of FLC-induced resistance to AMB for C. albicans also was assessed. In vitro, AMB monotherapy rapidly killed each of four C. albicans strains; FLC alone was fungistatic. Preincubation of these fungi with FLC for 18 h prior to exposure to AMB decreased their susceptibilities to AMB for 8 to >40 h. Induced resistance to AMB was transient, but the duration of resistance increased with the length of FLC preincubation. Yeast sequentially incubated with FLC followed by AMB plus FLC (FLC→AMB+FLC) showed fungistatic growth kinetics similar to that of fungi that were exposed to FLC alone. This antagonistic effect persisted for at least 24 h. Simultaneous exposure of C. albicans to AMB and FLC [AMB+FLC(simult)] demonstrated activity similar to that with AMB alone for AMB concentrations of ≥1 μg/ml; antagonism was seen using an AMB concentration of 0.5 μg/ml. The in vitro findings accurately predicted outcomes in our rabbit infection model. In vivo, AMB monotherapy and treatment with AMB for 24 h followed by AMB plus FLC (AMB→AMB+FLC) rapidly sterilized kidneys and cardiac vegetations. AMB+FLC(simult) and FLC→AMB treatments were slower in clearing fungi from infected tissues. FLC monotherapy and FLC→AMB+FLC were both fungistatic and were the least active regimens. No adverse interaction was observed between AMB and FLC for the AMB→FLC regimen. However, FLC→AMB treatment was slower than AMB alone in clearing fungi from tissues. Thus, our in vitro and in vivo studies both demonstrate that preexposure of C. albicans to FLC reduces fungal susceptibility to AMB. The length of FLC preexposure and whether AMB is subsequently used alone or in combination with FLC determine the duration of induced resistance to AMB.

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Role of Hyaluronan in Human Adipogenesis: Evidence from in-Vitro and in-Vivo Studies

International Journal of Molecular Sciences ◽

10.3390/ijms20112675 ◽

2019 ◽

Vol 20 (11) ◽

pp. 2675 ◽

Cited By ~ 1

Author(s):

Nicholas Wilson ◽

Robert Steadman ◽

Ilaria Muller ◽

Mohd Draman ◽

D. Aled Rees ◽

...

Keyword(s):

Stem Cell Differentiation ◽

In Vivo Studies ◽

Peroxisome Proliferator ◽

Synthesis Inhibitor ◽

Peroxisome Proliferator Activated Receptor ◽

Inhibitory Role ◽

The Impact

Hyaluronan (HA), an extra-cellular matrix glycosaminoglycan, may play a role in mesenchymal stem cell differentiation to fat but results using murine models and cell lines are conflicting. Our previous data, illustrating decreased HA production during human adipogenesis, suggested an inhibitory role. We have investigated the role of HA in adipogenesis and fat accumulation using human primary subcutaneous preadipocyte/fibroblasts (PFs, n = 12) and subjects of varying body mass index (BMI). The impact of HA on peroxisome proliferator-activated receptor gamma (PPARγ) expression was analysed following siRNA knockdown or HA synthase (HAS)1 and HAS2 overexpression. PFs were cultured in complete or adipogenic medium (ADM) with/without 4-methylumbelliferone (4-MU = HA synthesis inhibitor). Adipogenesis was evaluated using oil red O (ORO), counting adipogenic foci, and measurement of a terminal differentiation marker. Modulating HA production by HAS2 knockdown or overexpression increased (16%, p < 0.04) or decreased (30%, p = 0.01) PPARγ transcripts respectively. The inhibition of HA by 4-MU significantly enhanced ADM-induced adipogenesis with 1.52 ± 0.18- (ORO), 4.09 ± 0.63- (foci) and 2.6 ± 0.21-(marker)-fold increases compared with the controls, also increased PPARγ protein expression (40%, (p < 0.04)). In human subjects, circulating HA correlated negatively with BMI and triglycerides (r = −0.396 (p = 0.002), r = −0.269 (p = 0.038), respectively), confirming an inhibitory role of HA in human adipogenesis. Thus, enhancing HA action may provide a therapeutic target in obesity.

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Exposure to airborne gold nanoparticles: a review of current toxicological data on the respiratory tract

Journal of Nanoparticle Research ◽

10.1007/s11051-020-04966-9 ◽

2020 ◽

Vol 22 (8) ◽

Author(s):

Barbara De Berardis ◽

Magda Marchetti ◽

Anna Risuglia ◽

Federica Ietto ◽

Carla Fanizza ◽

...

Keyword(s):

Gold Nanoparticles ◽

Human Health ◽

Large Scale ◽

Current Knowledge ◽

Engineered Nanoparticles ◽

In Vivo Studies ◽

Field Exposure ◽

The Impact

AbstractIn recent years, the introduction of innovative low-cost and large-scale processes for the synthesis of engineered nanoparticles with at least one dimension less than 100 nm has led to countless useful and extensive applications. In this context, gold nanoparticles stimulated a growing interest, due to their peculiar characteristics such as ease of synthesis, chemical stability and optical properties. This stirred the development of numerous applications especially in the biomedical field. Exposure of manufacturers and consumers to industrial products containing nanoparticles poses a potential risk to human health and the environment. Despite this, the precise mechanisms of nanomaterial toxicity have not yet been fully elucidated. It is well known that the three main routes of exposure to nanomaterials are by inhalation, ingestion and through the skin, with inhalation being the most common route of exposure to NPs in the workplace. To provide a complete picture of the impact of inhaled gold nanoparticles on human health, in this article, we review the current knowledge about the physico-chemical characteristics of this nanomaterial, in the size range of 1–100 nm, and its toxicity for pulmonary structures both in vitro and in vivo. Studies comparing the toxic effect of NPs larger than 100 nm (up to 250 nm) are also discussed.

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Development of an LDL Receptor-Targeted Peptide Susceptible to Facilitate the Brain Access of Diagnostic or Therapeutic Agents

Biology ◽

10.3390/biology9070161 ◽

2020 ◽

Vol 9 (7) ◽

pp. 161

Author(s):

Séverine André ◽

Lionel Larbanoix ◽

Sébastien Verteneuil ◽

Dimitri Stanicki ◽

Denis Nonclercq ◽

...

Keyword(s):

Ldl Receptor ◽

Density Lipoprotein ◽

Therapeutic Agents ◽

In Vivo Studies ◽

Phage Display Technology ◽

Brain Penetration ◽

Wide Range ◽

The Brain

Blood-brain barrier (BBB) crossing and brain penetration are really challenging for the delivery of therapeutic agents and imaging probes. The development of new crossing strategies is needed, and a wide range of approaches (invasive or not) have been proposed so far. The receptor-mediated transcytosis is an attractive mechanism, allowing the non-invasive penetration of the BBB. Among available targets, the low-density lipoprotein (LDL) receptor (LDLR) shows favorable characteristics mainly because of the lysosome-bypassed pathway of LDL delivery to the brain, allowing an intact discharge of the carried ligand to the brain targets. The phage display technology was employed to identify a dodecapeptide targeted to the extracellular domain of LDLR (ED-LDLR). This peptide was able to bind the ED-LDLR in the presence of natural ligands and dissociated at acidic pH and in the absence of calcium, in a similar manner as the LDL. In vitro, our peptide was endocytosed by endothelial cells through the caveolae-dependent pathway, proper to the LDLR route in BBB, suggesting the prevention of its lysosomal degradation. The in vivo studies performed by magnetic resonance imaging and fluorescent lifetime imaging suggested the brain penetration of this ED-LDLR-targeted peptide.

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Impact of Mucin on Drug Diffusion: Development of a Straightforward In Vitro Method for the Determination of Drug Diffusivity in the Presence of Mucin

Pharmaceutics ◽

10.3390/pharmaceutics12020168 ◽

2020 ◽

Vol 12 (2) ◽

pp. 168 ◽

Cited By ~ 1

Author(s):

Margherita Falavigna ◽

Paul Stein ◽

Gøril Flaten ◽

Massimiliano di Cagno

Keyword(s):

Drug Interaction ◽

Drug Absorption ◽

Cost Effective ◽

Physicochemical Characteristics ◽

In Vivo Studies ◽

Phospholipid Vesicle ◽

Mucus Layer ◽

The Impact

Mucosal drug delivery accounts for various administration routes (i.e., oral, vaginal, ocular, pulmonary, etc.) and offers a vast surface for the permeation of drugs. However, the mucus layer which shields and lubricates all mucosal tissues can compromise drugs from reaching the epithelial site, thus affecting their absorption and therapeutic effect. Therefore, the effect of the mucus layer on drug absorption has to be evaluated early in the drug-development phase, prior to in vivo studies. For this reason, we developed a simple, cost-effective and reproducible method employing UV-visible localized spectroscopy for the assessment of the interaction between mucin and drugs with different physicochemical characteristics. The mucin–drug interaction was investigated by measuring the drug relative diffusivity (Drel) in the presence of mucin, and the method was validated by fitting experimental and mathematical data. In vitro permeability studies were also performed using the mucus-covered artificial permeation barrier (mucus–PVPA, Phospholipid Vesicle-based Permeation Assay) for comparison. The obtained results showed that the diffusion of drugs was hampered by the presence of mucin, especially at higher concentrations. This novel method proved to be suitable for the investigation on the extent of mucin–drug interaction and can be successfully used to assess the impact that the mucus layer has on drug absorption.

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