Lack of Biological Activities in the Extracellular Products of Renibacterium salmoninarum

1991 ◽  
Vol 48 (3) ◽  
pp. 421-425 ◽  
Author(s):  
I. Bandin ◽  
Y. Santos ◽  
D. W. Bruno ◽  
R. S. Raynard ◽  
A. E. Toranzo ◽  
...  

Evaluation in vivo and in vitro of the extracellular products (ECP) of a group of Renibacterium salmoninarum strains from different geographic origins revealed a low production of extracellular proteins in all strains and confirmed that most of the isolates were poor producers of proteolytic enzymes. The ECP displayed neither haemolytic activity nor capacity to alter the osmotic equilibrium of fish erythrocytes. In addition, none of the ECP samples displayed cytotoxic activities regardless of the origin of the cell line employed and did not contain substances lethal for fish, since no mortalities were recorded when doses ranging from 10 to 20 μg protein/g fish were administered. Although the present work failed to demonstrate toxicity in vivo of the ECP, it is possible that some extracellular enzymes contribute to the weakening of fish during the disease process and allow bacterial survival.

2020 ◽  
Vol 14 (4) ◽  
pp. 295-311
Author(s):  
Ada Gabriel ◽  
Mamman Mohammed ◽  
Mohammed G. Magaji ◽  
Yusuf P. Ofemile ◽  
Ameh P. Matthew ◽  
...  

Background: Snakebite envenomation is a global priority ranked top among other neglected tropical diseases. There is a folkloric claim that Uvaria chamae is beneficial for the management of snakebite and wounds in African ethnobotanical surveys. Besides, there are many registered patents asserting the health benefits of U. chamae. Objective: This study aimed to investigate U. chamae’s potentials and identify candidates for the development of tools for the treatment and management of N. nigricollis envenomation. Methods: Freshly collected U. chamae leaves were air-dried, powdered, and extracted in methanol. The median lethal dose of the extract was determined and further fractionated with n-hexane, n-butanol and ethyl acetate. Each fraction was tested for neutralizing effect against venom-induced haemolytic, fibrinolytic, hemorrhagic, and cytotoxic activities. Results: U. chamae fractions significantly (p<0.05) neutralized the haemolytic activity of N. nigricollis venom in n-butanol; 31.40%, n-hexane; 33%, aqueous residue; 39.60% and ethyl acetate; 40.70% at the concentration of 100mg/ml of each fraction against 10mg/ml of the snake venom when compared to the positive control. The fibrinolytic activity of N. nigricollis venom was significantly (p<0.05) neutralized in n-hexane at 73.88%, n-butanol; 72.22% and aqueous residue; 72.22% by the fractions of U. chamae. In addition, haemorrhagic activity of N. nigricollis venom was significantly (p<0.05) neutralized by U. chamae fractions at the concentrations of 100mg/ml, 200mg/ml and 400mg/ml except for n-butanol and aqueous residues at 400 mg/ml. Conclusion: U. chamae leaves fractions possess a high level of protection against N. nigricollis venoms-induced lethality and thus validate the pharmacological rationale for its usage in the management of N. nigricollis envenomation.


1998 ◽  
Vol 64 (11) ◽  
pp. 4269-4275 ◽  
Author(s):  
M. Carmen Balebona ◽  
Manuel J. Andreu ◽  
M. Angeles Bordas ◽  
Irene Zorrilla ◽  
Miguel A. Moriñigo ◽  
...  

ABSTRACT The in vivo and in vitro pathogenic activities of whole cells and extracellular products of Vibrio alginolyticus for cultured gilt-head sea bream were evaluated. The 50% lethal doses ranged from 5.4 × 104 to 1.0 × 106 CFU/g of body weight. The strains examined had the ability to adhere to skin, gill, and intestinal mucus of sea bream and to cultured cells of a chinook salmon embryo cell line. In addition, the in vitro ability ofV. alginolyticus to adhere to mucus and skin cells of sea bream was demonstrated by scanning electron microscopy. The biological activities of extracellular products of V. alginolyticus were hydrolytic activities; the products were able to degrade sea bream mucus. V. alginolyticus was cytotoxic for fish cell lines and lethal for sea bream. Moreover, the extracellular products could degrade sea bream tissues. However, experiments performed with the bath immersion inoculation technique demonstrated that V. alginolyticus should be considered a pathogen for sea bream only when the mucus layer is removed and the skin is damaged.


2010 ◽  
Vol 63 (5) ◽  
pp. 771 ◽  
Author(s):  
Norelle L. Daly ◽  
Bin Chen ◽  
Philip Nguyencong ◽  
David J. Craik

Cyclotides are plant-derived macrocyclic peptides with potential applications in the pharmaceutical and agricultural industries. In addition to their presumed natural function as host-defence peptides arising from their insecticidal activity, their other biological activities include antimicrobial, haemolytic, and cytotoxic activities, but at present, only limited information is available on the structural and chemical features that are important for these various activities. In the current study, we determined the three-dimensional structure of vhl-2, a leaf-specific cyclotide. Although the characteristic cyclic cystine knot fold of other cyclotides is maintained in vhl-2, it has more potent haemolytic activity than well-characterized cyclotides such as kalata B1 and kalata B8. Analysis of surface hydrophobicity and haemolytic activity for a range of cyclotides indicates a correlation between them, with increasing hydrophobicity resulting in increased haemolytic activity. This correlation is consistent with membrane binding being a vital step in mediating the various cytotoxic activities of cyclotides. The gene sequence for vhl-2 was determined and indicates that vhl-2 is processed from a multidomain precursor protein that also encodes the cyclotide cycloviolacin H3.


Molecules ◽  
2019 ◽  
Vol 24 (9) ◽  
pp. 1842 ◽  
Author(s):  
Yue-Xian Jin ◽  
Lei-Ling Shi ◽  
Da-Peng Zhang ◽  
Hong-Yan Wei ◽  
Yuan Si ◽  
...  

Natural daphnane diterpenoids, mainly distributed in plants of the Thymelaeaceae and Euphorbiaceae families, usually include a 5/7/6-tricyclic ring system with poly-hydroxyl groups located at C-3, C-4, C-5, C-9, C-13, C-14, or C-20, while some special types have a characteristic orthoester motif triaxially connectedat C-9, C-13, and C-14. The daphnane-type diterpenoids can be classified into five types: 6-epoxy daphnane diterpenoids, resiniferonoids, genkwanines, 1-alkyldaphnanes and rediocides, based on the oxygen-containing functions at rings B and C, as well as the substitution pattern of ring A. Up to now, nearly 200 daphnane-type diterpenoids have been isolated and elucidated from the Thymelaeaceae and Euphorbiaceae families. In-vitro and in-vivo experiments of these compounds have shown that they possess a wide range of biological activities, including anti-HIV, anti-cancer, anti-leukemic, neurotrophic, pesticidal and cytotoxic effects. A comprehensive account of the structural diversity is given in this review, along with the cytotoxic activities of daphnane-type diterpenoids, up to April 2019.


2020 ◽  
Vol 2020 ◽  
pp. 1-20 ◽  
Author(s):  
Mehdi Taib ◽  
Yassine Rezzak ◽  
Lahboub Bouyazza ◽  
Badiaa Lyoussi

Quercus species, also known as oak, represent an important genus of the Fagaceae family. It is widely distributed in temperate forests of the northern hemisphere and tropical climatic areas. Many of its members have been used in traditional medicine to treat and prevent various human disorders such as asthma, hemorrhoid, diarrhea, gastric ulcers, and wound healing. The multiple biological activities including anti-inflammatory, antibacterial, hepatoprotective, antidiabetic, anticancer, gastroprotective, antioxidant, and cytotoxic activities have been ascribed to the presence of bioactive compounds such as triterpenoids, phenolic acids, and flavonoids. This paper aimed to provide available information on the medicinal uses, phytochemicals, and pharmacology of species from Quercus. However, further investigation is needed to fully clarify the mode of action of its bioactive compounds and to evaluate in vivo chronic toxicity, before exploring their potential use as a supplement in functional foods and natural pharmaceutics.


2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Edina H. Avdović ◽  
Isidora P. Petrović ◽  
Milena J. Stevanović ◽  
Luciano Saso ◽  
Jasmina M. Dimitrić Marković ◽  
...  

Two newly synthesized 4-hydroxycoumarin bidentate ligands (L1 and L2) and their palladium(II) complexes (C1 and C2) were screened for their biological activities, in vitro and in vivo. Structures of new compounds were established based on elemental analysis, 1H NMR, 13C NMR, and IR spectroscopic techniques. The obtained compounds were tested for their antioxidative and cytotoxic activities and results pointed to selective antiradical activity of palladium(II) complexes towards •OH and -•OOH radicals and anti-ABTS (2,2 ′ -Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical) activity comparable to that of ascorbate. Results indicated the effect of C1 and C2 on the enzymatic activity of the antioxidative defense system. In vitro cytotoxicity assay performed on different carcinoma cell lines (HCT166, A375, and MIA PaCa-2), and one healthy fibroblast cell line (MRC-5) showed a cytotoxic effect of both C1 and C2, expressed as a decrease in carcinoma cells’ viability, mostly by induction of apoptosis. In vivo toxicity tests performed on zebrafish embryos indicated different effects of C1 and C2, ranging from adverse developmental effect to no toxicity, depending on tested concentration. According to docking studies, both complexes (C1 and C2) showed better inhibitory activity in comparison to other palladium(II) complexes.


2020 ◽  
Vol 27 ◽  
Author(s):  
Leydianne Leite de Siqueira Patriota ◽  
Dayane Kelly Dias do Nascimento Santos ◽  
Bárbara Rafaela da Silva Barros ◽  
Lethícia Maria de Souza Aguiar ◽  
Yasmym Araújo Silva ◽  
...  

Background: Protease inhibitors have been isolated from plants and present several biological activities, including immunomod-ulatory action. Objective: This work aimed to evaluate a Moringa oleifera flower trypsin inhibitor (MoFTI) for acute toxicity in mice, hemolytic activity on mice erythrocytes and immunomodulatory effects on mice splenocytes. Methods: The acute toxicity was evaluated using Swiss female mice that received a single dose of the vehicle control or MoFTI (300 mg/kg, i.p.). Behavioral alterations were observed 15–240 min after administration, and survival, weight gain, and water and food consumption were analyzed daily. Organ weights and hematological parameters were analyzed after 14 days. Hemolytic activity of MoFTI was tested using Swiss female mice erythrocytes. Splenocytes obtained from BALB/c mice were cultured in the absence or presence of MoFTI for the evaluation of cell viability and proliferation. Mitochondrial membrane potential (ΔΨm) and reactive oxygen species (ROS) levels were also determined. Furthermore, the culture supernatants were analyzed for the presence of cytokines and nitric oxide (NO). Results: MoFTI did not cause death or any adverse effects on the mice except for abdominal contortions at 15–30 min after administration. MoFTI did not exhibit a significant hemolytic effect. In addition, MoFTI did not induce apoptosis or necrosis in splenocytes and had no effect on cell proliferation. Increases in cytosolic and mitochondrial ROS release, as well as ΔΨm reduction, were observed in MoFTI-treated cells. MoFTI was observed to induce TNF-α, IFN-γ, IL-6, IL-10, and NO release. Conclusion: These results contribute to the ongoing evaluation of the antitumor potential of MoFTI and its effects on other immunological targets.


2019 ◽  
Vol 25 (37) ◽  
pp. 4888-4902 ◽  
Author(s):  
Gilda D'Urso ◽  
Sonia Piacente ◽  
Cosimo Pizza ◽  
Paola Montoro

The consumption of berry-type fruits has become very popular in recent years because of their positive effects on human health. Berries are in fact widely known for their health-promoting benefits, including prevention of chronic disease, cardiovascular disease and cancer. Berries are a rich source of bioactive metabolites, such as vitamins, minerals, and phenolic compounds, mainly anthocyanins. Numerous in vitro and in vivo studies recognized the health effects of berries and their function as bioactive modulators of various cell functions associated with oxidative stress. Plants have one of the largest metabolome databases, with over 1200 papers on plant metabolomics published only in the last decade. Mass spectrometry (MS) and NMR (Nuclear Magnetic Resonance) are the most important analytical technologies on which the emerging ''omics'' approaches are based. They may provide detection and quantization of thousands of biologically active metabolites from a tissue, working in a ''global'' or ''targeted'' manner, down to ultra-trace levels. In the present review, we highlighted the use of MS and NMR-based strategies and Multivariate Data Analysis for the valorization of berries known for their biological activities, important as food and often used in the preparation of nutraceutical formulations.


2020 ◽  
Vol 27 (12) ◽  
pp. 1955-1996 ◽  
Author(s):  
Antonio Speciale ◽  
Antonella Saija ◽  
Romina Bashllari ◽  
Maria Sofia Molonia ◽  
Claudia Muscarà ◽  
...  

: Chronic Noncommunicable Diseases (NCDs), mostly represented by cardiovascular diseases, diabetes, chronic pulmonary diseases, cancers, and several chronic pathologies, are one of the main causes of morbidity and mortality, and are mainly related to the occurrence of metabolic risk factors. Anthocyanins (ACNs) possess a wide spectrum of biological activities, such as anti-inflammatory, antioxidant, cardioprotective and chemopreventive properties, which are able to promote human health. Although ACNs present an apparent low bioavailability, their metabolites may play an important role in the in vivo protective effects observed. : This article directly addresses the scientific evidences supporting that ACNs could be useful to protect human population against several NCDs not only acting as antioxidant but through their capability to modulate cell redox-dependent signaling. In particular, ACNs interact with the NF-κB and AP-1 signal transduction pathways, which respond to oxidative signals and mediate a proinflammatory effect, and the Nrf2/ARE pathway and its regulated cytoprotective proteins (GST, NQO, HO-1, etc.), involved in both cellular antioxidant defenses and elimination/inactivation of toxic compounds, so countering the alterations caused by conditions of chemical/oxidative stress. In addition, supposed crosstalks could contribute to explain the protective effects of ACNs in different pathological conditions characterized by an altered balance among these pathways. Thus, this review underlines the importance of specific nutritional molecules for human health and focuses on the molecular targets and the underlying mechanisms of ACNs against various diseases.


2019 ◽  
Vol 20 (4) ◽  
pp. 285-292 ◽  
Author(s):  
Abdullah M. Alnuqaydan ◽  
Bilal Rah

Background:Tamarix Articulata (T. articulata), commonly known as Tamarisk or Athal in Arabic region, belongs to the Tamaricaece species. It is an important halophytic medicinal plant and a good source of polyphenolic phytochemical(s). In traditional medicines, T. articulata extract is commonly used, either singly or in combination with other plant extracts against different ailments since ancient times.Methods:Electronic database survey via Pubmed, Google Scholar, Researchgate, Scopus and Science Direct were used to review the scientific inputs until October 2018, by searching appropriate keywords. Literature related to pharmacological activities of T. articulata, Tamarix species, phytochemical analysis of T. articulata, biological activities of T. articulata extracts. All of these terms were used to search the scientific literature associated with T. articulata; the dosage of extract, route of administration, extract type, and in-vitro and in-vivo model.Results:Numerous reports revealed that T. articulata contains a wide spectrum of phytochemical(s), which enables it to have a wide window of biological properties. Owing to the presence of high content of phytochemical compounds like polyphenolics and flavonoids, T. articulata is a potential source of antioxidant, anti-inflammatory and antiproliferative properties. In view of these pharmacological properties, T. articulata could be a potential drug candidate to treat various clinical conditions including cancer in the near future.Conclusion:In this review, the spectrum of phytochemical(s) has been summarized for their pharmacological properties and the mechanisms of action, and the possible potential therapeutic applications of this plant against various diseases discussed.


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