scholarly journals Potential of Prebiotic D-Tagatose for Prevention of Oral Disease

2021 ◽  
Vol 11 ◽  
Author(s):  
Shota Mayumi ◽  
Masae Kuboniwa ◽  
Akito Sakanaka ◽  
Ei Hashino ◽  
Asuka Ishikawa ◽  
...  
Keyword(s):  
Amino Acids ◽  
Bacterial Species ◽  
Viable Cell ◽  
Oral Disease ◽  
Dependent Manner ◽  
Oral Streptococci ◽  
Concentration Dependent Manner ◽  
Carbohydrate Source ◽  
Dental Biofilm

Recent studies have shown phenotypic and metabolic heterogeneity in related species including Streptococcus oralis, a typical oral commensal bacterium, Streptococcus mutans, a cariogenic bacterium, and Streptococcus gordonii, which functions as an accessory pathogen in periodontopathic biofilm. In this study, metabolites characteristically contained in the saliva of individuals with good oral hygiene were determined, after which the effects of an identified prebiotic candidate, D-tagatose, on phenotype, gene expression, and metabolic profiles of those three key bacterial species were investigated. Examinations of the saliva metabolome of 18 systemically healthy volunteers identified salivary D-tagatose as associated with lower dental biofilm abundance in the oral cavity (Spearman’s correlation coefficient; r = -0.603, p = 0.008), then the effects of D-tagatose on oral streptococci were analyzed in vitro. In chemically defined medium (CDM) containing D-tagatose as the sole carbohydrate source, S. mutans and S. gordonii each showed negligible biofilm formation, whereas significant biofilms were formed in cultures of S. oralis. Furthermore, even in the presence of glucose, S. mutans and S. gordonii showed growth suppression and decreases in the final viable cell count in a D-tagatose concentration-dependent manner. In contrast, no inhibitory effects of D-tagatose on the growth of S. oralis were observed. To investigate species-specific inhibition by D-tagatose, the metabolomic profiles of D-tagatose-treated S. mutans, S. gordonii, and S. oralis cells were examined. The intracellular amounts of pyruvate-derived amino acids in S. mutans and S. gordonii, but not in S. oralis, such as branched-chain amino acids and alanine, tended to decrease in the presence of D-tagatose. This phenomenon indicates that D-tagatose inhibits growth of those bacteria by affecting glycolysis and its downstream metabolism. In conclusion, the present study provides evidence that D-tagatose is abundant in saliva of individuals with good oral health. Additionally, experimental results demonstrated that D-tagatose selectively inhibits growth of the oral pathogens S. mutans and S. gordonii. In contrast, the oral commensal S. oralis seemed to be negligibly affected, thus highlighting the potential of administration of D-tagatose as an oral prebiotic for its ability to manipulate the metabolism of those targeted oral streptococci.

Influence of ammonia concentration on [15N]ammonia uptake andde novosynthesis of different amino acids by mixed rumen microorganisms from the sheep rumenin vitro

1999 ◽  
Vol 1999 ◽  
pp. 212-212 ◽  
Author(s):  
C. Atasoglu ◽  
C.J. Newbold ◽  
R.J. Wallace
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
De Novo ◽  
Ammonia Concentration ◽  
Dependent Manner ◽  
Microbial Protein ◽  
Concentration Dependent Manner ◽  
Rumen Microorganisms ◽  
Ammonia Uptake

Ammonia is thought to be the main source of nitrogen for protein synthesis by the rumen microorganisms, but peptides and amino acids derived from protein degradation are also incorporated into microbial protein. Recent experiments carried out by Atasogluet al.(1998) demonstrated that preformed amino acids decrease the uptake of ammonia into microbial protein and microbial amino acids in a concentration-dependent manner. However, little is known about how rumen ammonia concentrations affect ammonia uptake into microbial protein. The present study was undertaken to determine the influence of rumen ammonia concentrations on ammonia incorporation andde novosynthesis of individual amino acids by the mixed rumen microorganismsin vitro.

scholarly journals Taurolidine Acts on Bacterial Virulence Factors and Does Not Induce Resistance in Periodontitis-Associated Bacteria—An In-Vitro Study

Antibiotics ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 166
Author(s):  
Sabrina Radakovic ◽  
Nicola Andreoli ◽  
Simon Schmid ◽  
Sandor Nietzsche ◽  
Jürg Zumbrunn ◽  
...  
Keyword(s):  
Virulence Factors ◽  
Bacterial Species ◽  
Rare Event ◽  
In Vitro Study ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Minimal Inhibitory Concentrations ◽  
Development Of Resistance ◽  
Subinhibitory Concentrations

The aims of the present study were: (a) to determine the mechanism of action of taurolidine against bacterial species associated with periodontal disease, and (b) to evaluate the potential development of resistance against taurolidine as compared with minocycline. After visualizing the mode of action of taurolidine by transmission electron micrographs, the interaction with most important virulence factors (lipopolysaccharide (LPS), Porphyromonas gingivalis gingipains, Aggregatibacter actinomycetemcomitans leukotoxin), was analyzed. Then, 14 clinical isolates from subgingival biofilm samples were transferred on agar plates containing subinhibitory concentrations of taurolidine or minocycline up to 50 passages. Before and after each 10 passages, minimal inhibitory concentrations (MICs) were determined. Increasing MICs were screened for efflux mechanism. Taurolidine inhibited in a concentration-dependent manner the activities of LPS and of the arginine-specific gingipains; however, an effect on A. actinomycetemcomitans leukotoxin was not detected. One P. gingivalis strain developed a resistance against taurolidine, which was probably linked with efflux mechanisms. An increase of MIC values of minocycline occurred in five of the 14 included strains after exposure to subinhibitory concentrations of the antibiotic. The present results indicate that: (a) taurolidine interacts with LPS and gingipains, and (b) development of resistance seems to be a rare event when using taurolidine.

scholarly journals Activity of taurolidine on species associated with periodontitis

2019 ◽  
Author(s):  
Sabrina Radakovic ◽  
Simon Schmid ◽  
Nicola Andreoli ◽  
Sandor Nietzsche ◽  
Jürg Zumbrunn ◽  
...  
Keyword(s):  
Cell Wall ◽  
Mode Of Action ◽  
Bacterial Species ◽  
Rare Event ◽  
Dependent Manner ◽  
Oral Streptococci ◽  
Concentration Dependent Manner ◽  
Development Of Resistance ◽  
Potential Development ◽  
Subinhibitory Concentrations

Abstract Background Taurolidine is thought to be an alternative antimicrobial in periodontal therapy. The purpose of this follow-up taurolidine study was to determine in more detail the mode of action of taurolidine against bacterial species being associated with periodontal disease. Further, a potential development of resistance against taurolidine in comparison with minocycline was to evaluate. Results Visualizing the mode of action of taurolidine to Porphyromonas gingivalis by scanning and transmission electron micrographs showed in part pores and release of constituents from the cell wall. The interaction of taurolidin with bacterial cell wall is also supported by the finding that taurolidine inhibited in a concentration-dependent manner the activities of LPS and of the P. gingivalis arginine-specific gingipains. However, an effect on A. actinomycetemcomitans leukotoxin was not found. When transferring 14 clinical isolates from subgingival biofilm samples (4 P. gingivalis, 2 A. actinomycetemcomitans, 2 Tannerella forsythia, 2 Fusobacterium nucleatum, 4 oral streptococci) on agar plates containing subinhibitory concentrations of taurolidine up to 50 passages, one P. gingivalis strain developed a resistance against taurolidine which was probably linked with efflux mechanisms. When antimicrobial pressure was removed, MIC reverted to baseline value. Testing development of resistance to minocycline in a similar way, an increase of MIC values occurred in five of the 14 included strains after exposure to subinhibitory concentrations of the antibiotic. Efflux might play a role in one A. actinomycetemcomitans strains, but obviously not in the other four strains. Removing antimicrobial pressure for a few passages did not revert the increased MIC values. Conclusion Taurolidine interacts with LPS and gingipains. Development of resistance seems to be a rare event when applying taurolidine. A potential development of resistance might be associated with efflux mechanisms.

scholarly journals Taurolidine acts on bacterial virulence factors and does not induce resistance in periodontitis-associated bacteria

2019 ◽  
Author(s):  
Sabrina Radakovic ◽  
Simon Schmid ◽  
Nicola Andreoli ◽  
Sandor Nietzsche ◽  
Jürg Zumbrunn ◽  
...  
Keyword(s):  
Cell Wall ◽  
Mode Of Action ◽  
Bacterial Species ◽  
Rare Event ◽  
Dependent Manner ◽  
Oral Streptococci ◽  
Concentration Dependent Manner ◽  
Development Of Resistance ◽  
Potential Development ◽  
Subinhibitory Concentrations

Abstract Background Taurolidine is thought to be an alternative antimicrobial in periodontal therapy. The purpose of this follow-up taurolidine study was to determine in more detail the mode of action of taurolidine against bacterial species being associated with periodontal disease. Further, a potential development of resistance against taurolidine in comparison with minocycline was to evaluate. Results Visualizing the mode of action of taurolidine to Porphyromonas gingivalis by scanning and transmission electron micrographs showed in part pores and release of constituents from the cell wall. The interaction of taurolidin with bacterial cell wall is also supported by the finding that taurolidine inhibited in a concentration-dependent manner the activities of LPS and of the P. gingivalis arginine-specific gingipains. However, an effect on A. actinomycetemcomitans leukotoxin was not found. When transferring 14 clinical isolates from subgingival biofilm samples (4 P. gingivalis, 2 A. actinomycetemcomitans, 2 Tannerella forsythia, 2 Fusobacterium nucleatum, 4 oral streptococci) on agar plates containing subinhibitory concentrations of taurolidine up to 50 passages, one P. gingivalis strain developed a resistance against taurolidine which was probably linked with efflux mechanisms. When antimicrobial pressure was removed, MIC reverted to baseline value. Testing development of resistance to minocycline in a similar way, an increase of MIC values occurred in five of the 14 included strains after exposure to subinhibitory concentrations of the antibiotic. Efflux might play a role in one A. actinomycetemcomitans strains, but obviously not in the other four strains. Removing antimicrobial pressure for a few passages did not revert the increased MIC values. Conclusion Taurolidine interacts with LPS and gingipains. Development of resistance seems to be a rare event when applying taurolidine. A potential development of resistance might be associated with efflux mechanisms.

Chickpea (Cicer arietinum L.) Lectin Exhibit Inhibition of ACE-I, α-amylase and α-glucosidase Activity

2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  
Keyword(s):  
Biological Effects ◽  
Exchange Chromatography ◽  
Health Concern ◽  
Carbohydrate Binding ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Ic50 Values ◽  
Chickpea Lectin

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.

Improved Method for Obtaining of Arctigenin from Arctium Lappa L. and its Antiproliferative Effect on Human Hepatocarcinoma HepG2 Cells

2020 ◽  
Vol 16 (3) ◽  
pp. 358-362
Author(s):  
Renan S. Teixeira ◽  
Paulo H.D. Carvalho ◽  
Jair A.K. Aguiar ◽  
Valquíria P. Medeiros ◽  
Ademar A. Da Silva Filho ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Crude Extract ◽  
Hepg2 Cells ◽  
Liver Carcinoma ◽  
Adhesion Assay ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Arctium Lappa ◽  
Nih 3T3

Background: Arctigenin is a lignan found in Arctium lappa L. (Asteraceae) that displays anti-inflammatory activities. Previous studies showed that the crude extract of A. Lappa has antitumor activity in human liver carcinoma, lung and stomach cancer cells. The aim of this study was to obtain arctigenin from A. lappa L., as well as to evaluate its antiproliferative effects in cells of liver carcinoma (HepG2) and fibroblasts (NIH/3T3). Methods: Arctigenin was obtained from the hydrolysis of arctiin, which was isolated from the crude extract of A. lappa. The effects of arctigenin and arctiin on HepG2 cell viability and cell adhesion were analyzed by MTT method. Adhesion assay was also carried out to evaluate the antitumor activity. Results: Our results showed that the analytical process to obtain arctigenin was fast and easy. In vitro experiments showed that arctigenin (107-269 μM) decreased HepG2 cells viability and did not cause cytotoxicity on NIH/3T3 cells. Arctigenin (27-269 μM) demonstrated anti-adhesion in HepG2 cells in a concentration-dependent manner, when compared with control. Conclusion: These results suggest a promising pharmacological activity for arctigenin as an antiproliferative compound.

scholarly journals Human Neuronal Cell Lines as An In Vitro Toxicological Tool for the Evaluation of Novel Psychoactive Substances

2021 ◽  
Vol 22 (13) ◽  
pp. 6785
Author(s):  
Valeria Sogos ◽  
Paola Caria ◽  
Clara Porcedda ◽  
Rafaela Mostallino ◽  
Franca Piras ◽  
...  
Keyword(s):  
Cell Death ◽  
Neuronal Cell ◽  
In Vitro Study ◽  
Dependent Manner ◽  
Novel Psychoactive Substances ◽  
Psychoactive Substances ◽  
Concentration Dependent Manner ◽  
Mechanisms Of Toxicity ◽  
Neuronal Cell Lines

Novel psychoactive substances (NPS) are synthetic substances belonging to diverse groups, designed to mimic the effects of scheduled drugs, resulting in altered toxicity and potency. Up to now, information available on the pharmacology and toxicology of these new substances is very limited, posing a considerable challenge for prevention and treatment. The present in vitro study investigated the possible mechanisms of toxicity of two emerging NPS (i) 4′-methyl-alpha-pyrrolidinoexanophenone (3,4-MDPHP), a synthetic cathinone, and (ii) 2-chloro-4,5-methylenedioxymethamphetamine (2-Cl-4,5-MDMA), a phenethylamine. In addition, to apply our model to the class of synthetic opioids, we evaluated the toxicity of fentanyl, as a reference compound for this group of frequently abused substances. To this aim, the in vitro toxic effects of these three compounds were evaluated in dopaminergic-differentiated SH-SY5Y cells. Following 24 h of exposure, all compounds induced a loss of viability, and oxidative stress in a concentration-dependent manner. 2-Cl-4,5-MDMA activates apoptotic processes, while 3,4-MDPHP elicits cell death by necrosis. Fentanyl triggers cell death through both mechanisms. Increased expression levels of pro-apoptotic Bax and caspase 3 activity were observed following 2-Cl-4,5-MDMA and fentanyl, but not 3,4-MDPHP exposure, confirming the different modes of cell death.

scholarly journals The Modulation of PCSK9 and LDLR by Supercritical CO2 Extracts of Mentha longifolia and Isolated Piperitone Oxide, an In Vitro Study

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3886
Author(s):  
Stefania Sut ◽  
Irene Ferrarese ◽  
Maria Giovanna Lupo ◽  
Nicola De Zordi ◽  
Elisa Tripicchio ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Cell Lines ◽  
Hepatoma Cell ◽  
Density Lipoprotein ◽  
In Vitro Study ◽  
Volatile Constituent ◽  
Dependent Manner ◽  
Human Hepatoma Cell ◽  
Concentration Dependent Manner

In the present study the ability of supercritical carbon dioxide (SCO2) extracts of M. longifolia L. leaves to modulate low-density lipoprotein receptor (LDLR) and proprotein convertase subtilisin/kexin type 9 (PCSK9) expression was evaluated in cultured human hepatoma cell lines Huh7 and HepG2. Two SCO2 extracts, one oil (ML-SCO2) and a semisolid (MW-SCO2), were subjected to detailed chemical characterization by mono- and bidimensional nuclear magnetic resonance (1D, 2D-NMR), gas chromatography coupled with mass spectrometry (GC-MS) and liquid chromatography coupled with mass spectrometry (LC-MS). Chemical analysis revealed significant amounts of fatty acids, phytosterols and terpenoids. ML-SCO2 was able to induce LDLR expression at a dose of 60 µg/mL in HuH7 and HepG2 cell lines. Furthermore, ML-SCO2 reduced PCSK9 secretion in a concentration-dependent manner in both cell lines. Piperitone oxide, the most abundant compound of the volatile constituent of ML-SCO2 (27% w/w), was isolated and tested for the same targets, showing a very effective reduction of PCSK9 expression. The overall results revealed the opportunity to obtain a new nutraceutical ingredient with a high amount of phytosterols and terpenoids using the SCO2 extraction of M. longifolia L., a very well-known botanical species used as food. Furthermore, for the first time we report the high activity of piperitone oxide in the reduction of PCSK9 expression.

scholarly journals Cannabidiol (CBD) Alters the Functionality of Neutrophils (PMN). Implications in the Refractory Epilepsy Treatment

2021 ◽  
Vol 14 (3) ◽  
pp. 220
Author(s):  
Claudia Taborda Gómez ◽  
Fabiana Lairion ◽  
Marisa Repetto ◽  
Miren Ettcheto ◽  
Amalia Merelli ◽  
...  
Keyword(s):  
Refractory Epilepsy ◽  
Polymorphonuclear Neutrophils ◽  
Dependent Manner ◽  
Nuclear Condensation ◽  
Concentration Dependent Manner ◽  
Superoxide Anion Production ◽  
Excretory Function ◽  
Psychoactive Effects ◽  
Stress Damage

Cannabidiol (CBD), a lipophilic cannabinoid compound without psychoactive effects, has emerged as adjuvant of anti-epileptic drugs (AEDs) in the treatment of refractory epilepsy (RE), decreasing the severity and/or frequency of seizures. CBD is considered a multitarget drug that could act throughout the canonical endocannabinoid receptors (CB1-CB2) or multiple non-canonical pathways. Despite the fact that the CBD mechanism in RE is still unknown, experiments carried out in our laboratory showed that CBD has an inhibitory role on P-glycoprotein excretory function, highly related to RE. Since CB2 is expressed mainly in the immune cells, we hypothesized that CBD treatment could alter the activity of polymorphonuclear neutrophils (PMNs) in a similar way that it does with microglia/macrophages and others circulating leukocytes. In vitro, CBD induced PMN cytoplasmatic vacuolization and proapoptotic nuclear condensation, associated with a significantly decreased viability in a concentration-dependent manner, while low CBD concentration decreased PMN viability in a time-dependent manner. At a functional level, CBD reduced the chemotaxis and oxygen consumption of PMNs related with superoxide anion production, while the singlet oxygen level was increased suggesting oxidative stress damage. These results are in line with the well-known CBD anti-inflammatory effect and support a potential immunosuppressor role on PMNs that could promote an eventual defenseless state during chronic treatment with CBD in RE.

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