scholarly journals In Vitro Chemopreventive Potential of Phlorotannins-Rich Extract from Brown Algae by Inhibition of Benzo[a]pyrene-Induced P2X7 Activation and Toxic Effects

Marine Drugs ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. 34
Author(s):  
Mélody Dutot ◽  
Elodie Olivier ◽  
Sophie Fouyet ◽  
Romain Magny ◽  
Karim Hammad ◽  
...  
Keyword(s):  
Brown Algae ◽  
P2x7 Receptor ◽  
Biological Activities ◽  
Receptor Activation ◽  
Cytotoxic Effects ◽  
Human Lung Cells ◽  
Cytochrome P450 Activity ◽  
Species Production ◽  
E Cadherin

Phlorotannins are polyphenols occurring exclusively in some species of brown algae, known for numerous biological activities, e.g., antioxidant, antiproliferative, antidiabetic, and antiallergic properties. Their effects on the response of human lung cells to benzo[a]pyrene (B[a]P) has not been characterized. Our objective was to in vitro evaluate the effects of a phlorotannin-rich extract obtained from the brown algae Ascophyllum nodosum and Fucus vesiculosus on B[a]P cytotoxic effects. The A549 cell line was incubated with B[a]P for 48 and 72 h in the presence or absence of the brown algae extract. Cytochrome P450 activity, activation of P2X7 receptor, F-actin disorganization, and loss of E-cadherin expression were assessed using microplate cytometry and fluorescence microscopy. Relative to control, incubation with the brown algae extract was associated with lower B[a]P-induced CYP1 activity, lower P2X7 receptor activation, and lower reactive oxygen species production. The brown algae extract inhibited the alterations of F-actin arrangement and the downregulation of E-cadherin expression. We identified a phlorotannins-rich extract that could be deeper investigated as a cancer chemopreventive agent to block B[a]P-mediated carcinogenesis.

In vitro biological activities and in vivo hepatoprotective role of brown algae-isolated fucoidans

2021 ◽  
Author(s):  
Marwa E. Atya ◽  
Amr El-Hawiet ◽  
Mohamed A. Alyeldeen ◽  
Doaa A. Ghareeb ◽  
Mohamed M. Abdel-Daim ◽  
...  
Keyword(s):  
Brown Algae ◽  
Biological Activities

scholarly journals The Comparative Analysis of Antiviral Activity of Native and Modified Fucoidans from Brown Algae Fucus evanescens In Vitro and In Vivo

Marine Drugs ◽  
2020 ◽  
Vol 18 (4) ◽  
pp. 224 ◽  
Author(s):  
Natalya V. Krylova ◽  
Svetlana P. Ermakova ◽  
Vyacheslav F. Lavrov ◽  
Irina A. Leneva ◽  
Galina G. Kompanets ◽  
...  
Keyword(s):  
Antiviral Activity ◽  
Brown Algae ◽  
Biological Activities ◽  
Intraperitoneal Administration ◽  
In Vivo Studies ◽  
Mice Model ◽  
Dna And Rna ◽  
Antiviral Activities

The enzymatic depolymerization of fucoidans from brown algae allowed the production of their standardized derivatives with different biological activities. This work aimed to compare the antiviral activities of native (FeF) and modified with enzyme (FeHMP) fucoidans from F. evanescens. The cytotoxicity and antiviral activities of the FeF and FeHMP against herpes viruses (HSV-1, HSV-2), enterovirus (ECHO-1), and human immunodeficiency virus (HIV-1) in Vero and human MT-4 cell lines were examined by methylthiazolyltetrazolium bromide (MTT) and cytopathic effect (CPE) reduction assays, respectively. The efficacy of fucoidans in vivo was evaluated in the outbred mice model of vaginitis caused by HSV-2. We have shown that both FeF and FeHMP significantly inhibited virus-induced CPE in vitro and were more effective against HSV. FeF exhibited antiviral activity against HSV-2 with a selective index (SI) > 40, and FeHMP with SI ˃ 20, when they were added before virus infection or at the early stages of the HSV-2 lifecycle. Furthermore, in vivo studies showed that after intraperitoneal administration (10 mg/kg), both FeF and FeHMP protected mice from lethal intravaginal HSV-2 infection to approximately the same degree (44–56%). Thus, FeF and FeHMP have comparable potency against several DNA and RNA viruses, allowing us to consider the studied fucoidans as promising broad-spectrum antivirals.

scholarly journals Lignans and Gut Microbiota: An Interplay Revealing Potential Health Implications

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5709
Author(s):  
Alice Senizza ◽  
Gabriele Rocchetti ◽  
Juana I. Mosele ◽  
Vania Patrone ◽  
Maria Luisa Callegari ◽  
...  
Keyword(s):  
Gut Microbiota ◽  
Biological Activities ◽  
Receptor Activation ◽  
Bacterial Metabolism ◽  
Plant Polyphenols ◽  
Potential Health ◽  
Plant Foods ◽  
Apoptotic Effects ◽  
Entire Gastrointestinal Tract

Plant polyphenols are a broad group of bioactive compounds characterized by different chemical and structural properties, low bioavailability, and several in vitro biological activities. Among these compounds, lignans (a non-flavonoid polyphenolic class found in plant foods for human nutrition) have been recently studied as potential modulators of the gut–brain axis. In particular, gut bacterial metabolism is able to convert dietary lignans into therapeutically relevant polyphenols (i.e., enterolignans), such as enterolactone and enterodiol. Enterolignans are characterized by various biologic activities, including tissue-specific estrogen receptor activation, together with anti-inflammatory and apoptotic effects. However, variation in enterolignans production by the gut microbiota is strictly related to both bioaccessibility and bioavailability of lignans through the entire gastrointestinal tract. Therefore, in this review, we summarized the most important dietary source of lignans, exploring the interesting interplay between gut metabolites, gut microbiota, and the so-called gut–brain axis.

scholarly journals Toxicological Evaluation of Piceatannol, Pterostilbene, and ε-Viniferin for Their Potential Use in the Food Industry: A Review

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 592
Author(s):  
Concepción Medrano-Padial ◽  
Ana Isabel Prieto ◽  
María Puerto ◽  
Silvia Pichardo
Keyword(s):  
Food Industry ◽  
Biological Activities ◽  
In Vitro Tests ◽  
Toxicological Evaluation ◽  
Cytotoxic Effects ◽  
Cancerous Cell ◽  
Toxicological Studies ◽  
Genotoxicity Testing

The application of stilbenes in the food industry is being considered because of their biological activities. Piceatannol, pterostilbene and ε-viniferin have awakened the industry’s interest. However, before they can be commercialized, we must first guarantee their safety for consumers. The present work reviews the toxicological studies performed with these stilbenes. A wide variety of studies has demonstrated their cytotoxic effects in both cancer and non-cancerous cell lines. In contrast, although DNA damage was detected by some authors, in vitro genotoxic studies on the effects of piceatannol, pterostilbene, and ε-viniferin remain scarce. None of the three reviewed substances have been evaluated using the in vitro tests required by the European Food Safety Authority (EFSA) as the first step in genotoxicity testing. We did not find any study on the toxic effects of these stilbenes in vivo. Thus, more studies are needed to confirm their safe use before they can be authorized as additive in the food industry.

scholarly journals Bisphenol A, Bisphenol F, and Bisphenol S: The Bad and the Ugly. Where Is the Good?

Life ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 314
Author(s):  
Sophie Fouyet ◽  
Elodie Olivier ◽  
Pascale Leproux ◽  
Mélody Dutot ◽  
Patrice Rat
Keyword(s):  
Bisphenol A ◽  
P2x7 Receptor ◽  
Chromatin Condensation ◽  
Receptor Activation ◽  
Bisphenol S ◽  
Safe Alternative ◽  
Bisphenol F ◽  
Placental Cells ◽  
Human Placental Cells

Background: Bisphenol A (BPA), a reprotoxic and endocrine-disrupting chemical, has been substituted by alternative bisphenols such as bisphenol F (BPF) and bisphenol S (BPS) in the plastic industry. Despite their detection in placenta and amniotic fluids, the effects of bisphenols on human placental cells have not been characterized. Our objective was to explore in vitro and to compare the toxicity of BPA to its substitutes BPF and BPS to highlight their potential risks for placenta and then pregnancy. Methods: Human placenta cells (JEG-Tox cells) were incubated with BPA, BPF, and BPS for 72 h. Cell viability, cell death, and degenerative P2X7 receptor and caspases activation, and chromatin condensation were assessed using microplate cytometry and fluorescence microscopy. Results: Incubation with BPA, BPF, or BPS was associated with P2X7 receptor activation and chromatin condensation. BPA and BPF induced more caspase-1, caspase-9, and caspase-3 activation than BPS. Only BPF enhanced caspase-8 activity. Conclusions: BPA, BPF, and BPS are all toxic to human placental cells, with the P2X7 receptor being a common key element. BPA substitution by BPF and BPS does not appear to be a safe alternative for human health, particularly for pregnant women and their fetuses.

scholarly journals Shedding Lights on Crude Venom from Solitary Foraging Predatory Ant Ectatomma opaciventre: Initial Toxinological Investigation

Toxins ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 37
Author(s):  
Lucas Ian Veloso Correia ◽  
Fernanda Van Petten de Vasconcelos Azevedo ◽  
Fernanda Gobbi Amorim ◽  
Sarah Natalie Cirilo Gimenes ◽  
Lorena Polloni ◽  
...  
Keyword(s):  
Biological Activities ◽  
Biological Effects ◽  
Acid Oxidase ◽  
Crude Venom ◽  
Amino Acid Oxidase ◽  
Cytotoxic Effects ◽  
Primary Hemostasis ◽  
High Enzymatic Activity ◽  
Predatory Ants

Some species of primitive predatory ants, despite living in a colony, exercise their hunting collection strategy individually; their venom is painful, paralyzing, digestive, and lethal for their prey, yet the toxins responsible for these effects are poorly known. Ectatomma opaciventre is a previously unrecorded solitary hunting ant from the Brazilian Cerrado. To overcome this hindrance, the present study performed the in vitro enzymatic, biochemical, and biological activities of E. opaciventre to better understand the properties of this venom. Its venom showed several proteins with masses ranging from 1–116 kDa, highlighting the complexity of this venom. Compounds with high enzymatic activity were described, elucidating different enzyme classes present in the venom, with the presence of the first L-amino acid oxidase in Hymenoptera venoms being reported. Its crude venom contributes to a state of blood incoagulability, acting on primary hemostasis, inhibiting collagen-induced platelet aggregation, and operating on the fibrinolysis of loose red clots. Furthermore, the E. opaciventre venom preferentially induced cytotoxic effects on lung cancer cell lines and three different species of Leishmania. These data shed a comprehensive portrait of enzymatic components, biochemical and biological effects in vitro, opening perspectives for bio-pharmacological application of E. opaciventre venom molecules.

scholarly journals ANTITUMOR SULFATED POLYSACCHARIDES FROM BROWN ALGAE Dictyota caribaea

2020 ◽  
Author(s):  
Alexia Nathália Brígido Assef ◽  
Bianca Barros da Costa ◽  
Thamyris Almeida Moreira ◽  
Luana David do Carmo ◽  
Tamiris de Fátima Goebel de Souza ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Brown Algae ◽  
Antitumor Effect ◽  
Biological Activities ◽  
Bioactive Molecules ◽  
Sulfated Polysaccharides ◽  
Spleen Weight ◽  
Tumor Growth Inhibition ◽  
White Pulp

AbstractSulfated polysaccharides (SP) are a complex group of bioactive molecules able to inhibit tumor growth. SP increase the effectiveness of chemotherapy and reduce some side effects. Brown algae produce SP with several biological activities including antitumor. This work aimed to investigate the antitumor effect of SP from the brown algae Dictyota caribaea (Dc-SP). Dc-SP were extracted with proteolytic enzyme and supernatant was precipitated with increasing concentrations of ethanol. Antiproliferative activity of Dc-SP was tested by the MTT assay against colon cancer (HCT 116) and metastatic melanoma (B16-F10) cell lines. The antitumor effect was evaluated on Swiss mice transplanted with sarcoma 180 tumor and treated i.p. during 7 days with saline or Dc-SP (25 and 50 mg/kg/animal). Dc-SP did not exhibit cytotoxicity in vitro, however the Dc-SP-treated mice depicted up to 50% tumor growth inhibition. Dc-SP treatment induced spleen weight increasing along with intense white pulp disorganization. Furthermore Dc-SP did not depict hepatic toxicity, nephrotoxicity nor leukopenia and did induce increase of platelets count. Altogether, these results represent a promising antitumor host dependent effect induced by Dc-SP.

scholarly journals Induction of Persistent Colitis by a Human Commensal, Enterotoxigenic Bacteroides fragilis, in Wild-Type C57BL/6 Mice

2009 ◽  
Vol 77 (4) ◽  
pp. 1708-1718 ◽  
Author(s):  
Ki-Jong Rhee ◽  
Shaoguang Wu ◽  
XinQun Wu ◽  
David L. Huso ◽  
Baktiar Karim ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Bacteroides Fragilis ◽  
Receptor Activation ◽  
Intestinal Epithelial ◽  
Wild Type ◽  
Bowel Diseases ◽  
Specific Pathogen ◽  
E Cadherin

ABSTRACT Enterotoxigenic Bacteroides fragilis (ETBF) causes diarrhea and is implicated in inflammatory bowel diseases and colorectal cancer. The only known ETBF virulence factor is the Bacteroides fragilis toxin (BFT), which induces E-cadherin cleavage, interleukin-8 secretion, and epithelial cell proliferation. A murine model for ETBF has not been characterized. Specific pathogen-free (SPF) C57BL/6J or germfree 129S6/SvEv mice were orally inoculated with wild-type ETBF (WT-ETBF) strains, a nontoxigenic WT strain of B. fragilis (WT-NTBF), WT-NTBF overexpressing bft (rETBF), or WT-NTBF overexpressing a biologically inactive mutated bft (rNTBF). In SPF and germfree mice, ETBF caused colitis but was lethal only in germfree mice. Colonic histopathology demonstrated mucosal thickening with inflammatory cell infiltration, crypt abscesses, and epithelial cell exfoliation, erosion, and ulceration. SPF mice colonized with rETBF mimicked WT-ETBF, whereas rNTBF caused no histopathology. Intestinal epithelial E-cadherin was rapidly cleaved in vivo in WT-ETBF-colonized mice and in vitro in intestinal tissues cultured with purified BFT. ETBF mice colonized for 16 months exhibited persistent colitis. BFT did not directly induce lymphocyte proliferation, dendritic cell stimulation, or Toll-like receptor activation. In conclusion, WT-ETBF induced acute then persistent colitis in SPF mice and rapidly lethal colitis in WT germfree mice. Our data support the hypothesis that chronic colonization with the human commensal ETBF can induce persistent, subclinical colitis in humans.

Multispecific antibodies targeting CD38 show potent tumor-specific cytotoxicity.

2018 ◽  
Vol 36 (5_suppl) ◽  
pp. 57-57 ◽  
Author(s):  
Shelley Force Aldred ◽  
Andrew Boudreau ◽  
Ben Buelow ◽  
Starlynn Clarke ◽  
Kevin Dang ◽  
...  
Keyword(s):  
Biological Activities ◽  
Building Blocks ◽  
In Vitro Models ◽  
Cytotoxic Effects ◽  
Antibody Therapeutics ◽  
T Cell Lymphomas ◽  
Single Antigen ◽  
Specific Cytotoxicity ◽  
Low Levels

57 Background: Multivalent antibodies targeting either CD38 alone or CD38 in conjunction with PD-L1 may yield therapeutics with superior biological activities and provide benefit for treating malignancies expressing low levels of CD38 (MCL, NHL, T cell lymphomas and Daratumumab refractory MM). Multivalent, multispecific antibodies kill CD38low cells through a variety of mechanisms including stronger and more specific engagement of CD38. Potent and directed immune checkpoint inhibition is realized by adding an anti-PD-L1 binding domain. Teneobio’s discovery platform utilizes VH domains (UniDabs) of fully human heavy chain antibodies (UniAbs) to develop bi-, tri-, and tetravalent antibodies. Methods: Individual UniDabs targeting CD38 and PDL1 were identified using our unique sequence-based discovery platform and high-throughput lead evaluation pipeline (TeneoSeek). This robust screening workflow enables evaluation of a large diversity of natural fully human antibodies, targeting multiple epitopes on a single antigen and uncovering important sequence activity relationships. UniDabs from transgenic rats are ideal building blocks for the generation of potent and highly manufacturable multivalent antibody therapeutics. Results: We have identified UniDabs that efficiently block PD-1/PD-L1 interaction as well as additional UniDabs that bind to five different functional epitopes on human CD38. Using different combinations and arrangements of UniDabs, a variety of multivalent antibodies were constructed and evaluated in in vitro models. Specific combinations of UniDabs show more potent cytotoxic effects than Daratumumab for multiple mechanisms including CDC and direct apoptosis. Conclusions: Data from a range of assay types show that multivalent UniAbs targeting CD38 can be engineered to display superior tumor cell cytotoxicity through multiple mechanisms of action.

Sign in / Sign up

Export Citation Format

Share Document