scholarly journals Effects of Glucose and Starch on Lactate Production by Newly Isolated Streptococcus bovis S1 from Saanen Goats

2016 ◽  
Vol 82 (19) ◽  
pp. 5982-5989 ◽  
Author(s):  
Lianmin Chen ◽  
Yang Luo ◽  
Hongrong Wang ◽  
Shimin Liu ◽  
Yizhao Shen ◽  
...  
Keyword(s):  
Organic Acid ◽  
Rumen Fluid ◽  
Lactate Production ◽  
Soluble Starch ◽  
Dependent Manner ◽  
Streptococcus Bovis ◽  
Dairy Goats ◽  
Content Type ◽  
Expression Levels ◽  
Rumen Acidosis

ABSTRACTWhen ruminants are fed high-concentrate diets,Streptococcus bovisproliferates rapidly and produces lactate, potentially causing rumen acidosis. Understanding the regulatory mechanisms of the metabolism of this species might help in developing dietary strategies to alleviate rumen acidosis.S. bovisstrain S1 was newly isolated from the ruminal fluid of Saanen dairy goats and then used to examine the effects of glucose and starch on bacterial metabolism and gene regulation of the organic acid-producing pathway in cultures at a pH of 6.5. Glucose or starch was added to the culture medium at 1 g/liter, 3 g/liter (close to a normal range in the rumen fluid), or 9 g/liter (excessive level). Lactate was the dominant acid produced during the fermentation, and levels increased with the amount of glucose or starch in a dose-dependent manner (P< 0.001). The production of formate and acetate in the fermentation media fluctuated slightly with the dose but accounted for small fractions of the total acids. The activities of lactate dehydrogenase (LDH) and α-amylase (α-AMY) increased with the starch dose (P< 0.05), but the α-AMY activity did not change with the glucose dose. The relative expression levels of the genesldh,pfl(encoding pyruvate formate lyase),ccpA(encoding catabolite control protein A), and α-amywere higher at a dose of 9 g/liter than at 1 g/liter (P< 0.05). Expression levels ofpfland α-amygenes were higher at 3 g/liter than at 1 g/liter (P< 0.05). The fructose 1,6-diphosphate (FDP) concentration tended to increase with the glucose and starch concentrations. In addition, theS. bovisS1 isolate fermented glucose much faster than starch. We conclude that the quantities of glucose and soluble starch had a major effect on lactate production due to the transcriptional regulation of metabolic genes.IMPORTANCEThis work used a newly isolatedS. bovisstrain S1 from the rumen fluid of Saanen goats and examined the effects of glucose and soluble starch on organic acid patterns, enzyme activity, and expression of genes forin vitrofermentation. It was found that lactate was the dominant product fromS. bovisstrain S1, and the quantities of both glucose and starch in the medium were highly correlated with lactate production and with the corresponding changes in associated enzymes and genes. Therefore, manipulating the metabolic pathway ofS. bovisto alter the dietary level of readily fermentable sugar and carbohydrates may be a strategy to alleviate rumen acidosis.

scholarly journals Evaluation of liquid and powdered forms of polyclonal antibody preparation against Streptococcus bovis and Fusobacterium necrophorum in cattle adapted or not adapted to highly fermentable carbohydrate diets

2021 ◽  
Vol 34 (1) ◽  
pp. 74-84
Author(s):  
Eduardo Cuellar Orlandi Cassiano ◽  
Flavio Perna Junior ◽  
Tarley Araújo Barros ◽  
Carolina Tobias Marino ◽  
Rodrigo Dias Lauritano Pacheco ◽  
...  
Keyword(s):  
Polyclonal Antibody ◽  
Rumen Fluid ◽  
Nitrogen Concentration ◽  
Fusobacterium Necrophorum ◽  
Rumen Fermentation ◽  
Feed Additives ◽  
Streptococcus Bovis ◽  
Metabolic Disturbances ◽  
Antibody Preparation ◽  
Rumen Acidosis

Objective: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against <i>Streptococcus bovis</i> and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet.Methods: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly.Results: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of <i>Entodinium</i> protozoa but copy numbers of <i>Streptococcus bovis</i> and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals.Conclusion: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

scholarly journals In VitroAnalyses of the Effects of Heparin and Parabens on Candida albicans Biofilms and Planktonic Cells

2011 ◽  
Vol 56 (1) ◽  
pp. 148-153 ◽  
Author(s):  
Marisa H. Miceli ◽  
Stella M. Bernardo ◽  
T. S. Neil Ku ◽  
Carla Walraven ◽  
Samuel A. Lee
Keyword(s):  
Candida Albicans ◽  
Metabolic Activity ◽  
Biofilm Formation ◽  
High Dose ◽  
Dependent Manner ◽  
Planktonic Cells ◽  
Content Type ◽  
Heparin Sodium ◽  
The Individual

ABSTRACTInfections and thromboses are the most common complications associated with central venous catheters. Suggested strategies for prevention and management of these complications include the use of heparin-coated catheters, heparin locks, and antimicrobial lock therapy. However, the effects of heparin onCandida albicansbiofilms and planktonic cells have not been previously studied. Therefore, we sought to determine thein vitroeffect of a heparin sodium preparation (HP) on biofilms and planktonic cells ofC. albicans. Because HP contains two preservatives, methyl paraben (MP) and propyl paraben (PP), these compounds and heparin sodium without preservatives (Pure-H) were also tested individually. The metabolic activity of the mature biofilm after treatment was assessed using XTT [2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] reduction and microscopy. Pure-H, MP, and PP caused up to 75, 85, and 60% reductions of metabolic activity of the mature preformedC. albicansbiofilms, respectively. Maximal efficacy against the mature biofilm was observed with HP (up to 90%) compared to the individual compounds (P< 0.0001). Pure-H, MP, and PP each inhibitedC. albicansbiofilm formation up to 90%. A complete inhibition of biofilm formation was observed with HP at 5,000 U/ml and higher. When tested against planktonic cells, each compound inhibited growth in a dose-dependent manner. These data indicated that HP, MP, PP, and Pure-H havein vitroantifungal activity againstC. albicansmature biofilms, formation of biofilms, and planktonic cells. Investigation of high-dose heparin-based strategies (e.g., heparin locks) in combination with traditional antifungal agents for the treatment and/or prevention ofC. albicansbiofilms is warranted.

scholarly journals Matrix Stiffness Modulates Metabolic Interaction between Human Stromal and Breast Cancer Cells to Stimulate Epithelial Motility

Metabolites ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 432
Author(s):  
Iván Ponce ◽  
Nelson Garrido ◽  
Nicolás Tobar ◽  
Francisco Melo ◽  
Patricio C. Smith ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cancer Progression ◽  
Stromal Cells ◽  
Glucose Transporter ◽  
Lactate Production ◽  
Resonance Energy ◽  
Metabolic Reprogramming ◽  
Dependent Manner ◽  
Functional Link

Breast tumors belong to the type of desmoplastic lesion in which a stiffer tissue structure is a determinant of breast cancer progression and constitutes a risk factor for breast cancer development. It has been proposed that cancer-associated stromal cells (responsible for this fibrotic phenomenon) are able to metabolize glucose via lactate production, which supports the catabolic metabolism of cancer cells. The aim of this work was to investigate the possible functional link between these two processes. To measure the effect of matrix rigidity on metabolic determinations, we used compliant elastic polyacrylamide gels as a substrate material, to which matrix molecules were covalently linked. We evaluated metabolite transport in stromal cells using two different FRET (Fluorescence Resonance Energy Transfer) nanosensors specific for glucose and lactate. Cell migration/invasion was evaluated using Transwell devices. We show that increased stiffness stimulates lactate production and glucose uptake by mammary fibroblasts. This response was correlated with the expression of stromal glucose transporter Glut1 and monocarboxylate transporters MCT4. Moreover, mammary stromal cells cultured on stiff matrices generated soluble factors that stimulated epithelial breast migration in a stiffness-dependent manner. Using a normal breast stromal cell line, we found that a stiffer extracellular matrix favors the acquisition mechanistical properties that promote metabolic reprograming and also constitute a stimulus for epithelial motility. This new knowledge will help us to better understand the complex relationship between fibrosis, metabolic reprogramming, and cancer malignancy.

scholarly journals Echinacoside exerts anti-tumor activity via the miR-503-3p/TGF-β1/Smad aixs in liver cancer

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wen Li ◽  
Jing Zhou ◽  
Yajie Zhang ◽  
Jing Zhang ◽  
Xue Li ◽  
...  
Keyword(s):  
Liver Cancer ◽  
Cancer Cells ◽  
Hepg2 Cells ◽  
Luciferase Reporter ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Expression Levels ◽  
Liver Cancer Cells ◽  
Anti Tumor Activity ◽  
Tgf Β1

Abstract Background Echinacoside (ECH) is the main active ingredient of Cistanches Herba, which is known to have therapeutic effects on metastatic tumors. However, the effects of ECH on liver cancer are still unclear. This study was to investigate the effects of ECH on the aggression of liver cancer cells. Methods Two types of liver cancer cells Huh7 and HepG2 were treated with different doses of ECH at different times and gradients. MTT and colony formation assays were used to determine the effects of ECH on the viability of Huh7 and HepG2 cells. Transwell assays and flow cytometry assays were used to detect the effects of ECH treatment on the invasion, migration, apoptosis and cell cycle of Huh7 and HepG2 cells. Western blot analysis was used to detect the effects of ECH on the expression levels of TGF-β1, smad3, smad7, apoptosis-related proteins (Caspase-3, Caspase-8), and Cyto C in liver cancer cells. The relationship between miR-503-3p and TGF-β1 was detected using bioinformatics analysis and Luciferase reporter assay. Results The results showed that ECH inhibited the proliferation, invasion and migration of Huh7 and HepG2 cells in a dose- and time-dependent manner. Moreover, we found that ECH caused Huh7 and HepG2 cell apoptosis by blocking cells in S phase. Furthermore, the expression of miR-503-3p was found to be reduced in liver tumor tissues, but ECH treatment increased the expression of miR-503-3p in Huh7 and HepG2 cells. In addition, we found that TGF-β1 was identified as a potential target of miR-503-3p. ECH promoted the activation of the TGF-β1/Smad signaling pathway and increased the expression levels of Bax/Bcl-2. Moreover, ECH could trigger the release of mitochondrial Cyto C, and cause the reaction Caspases grade. Conclusions This study demonstrates that ECH exerts anti-tumor activity via the miR-503-3p/TGF-β1/Smad aixs in liver cancer, and provides a safe and effective anti-tumor agent for liver cancer.

scholarly journals Investigation of Antifungal Mechanisms of Thymol in the Human Fungal Pathogen, Cryptococcus neoformans

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3476
Author(s):  
Kwang-Woo Jung ◽  
Moon-Soo Chung ◽  
Hyoung-Woo Bai ◽  
Byung Yeoup Chung ◽  
Sungbeom Lee
Keyword(s):  
Cryptococcus Neoformans ◽  
Fungal Pathogens ◽  
Reverse Genetics ◽  
Mapk Pathway ◽  
Global Climate ◽  
Mitogen Activated Protein Kinase ◽  
Ergosterol Biosynthesis ◽  
Thymus Vulgaris ◽  
Dependent Manner ◽  
Expression Levels

Due to lifespan extension and changes in global climate, the increase in mycoses caused by primary and opportunistic fungal pathogens is now a global concern. Despite increasing attention, limited options are available for the treatment of systematic and invasive mycoses, owing to the evolutionary similarity between humans and fungi. Although plants produce a diversity of chemicals to protect themselves from pathogens, the molecular targets and modes of action of these plant-derived chemicals have not been well characterized. Using a reverse genetics approach, the present study revealed that thymol, a monoterpene alcohol from Thymus vulgaris L., (Lamiaceae), exhibits antifungal activity against Cryptococcus neoformans by regulating multiple signaling pathways including calcineurin, unfolded protein response, and HOG (high-osmolarity glycerol) MAPK (mitogen-activated protein kinase) pathways. Thymol treatment reduced the intracellular concentration of Ca2+ by controlling the expression levels of calcium transporter genes in a calcineurin-dependent manner. We demonstrated that thymol decreased N-glycosylation by regulating the expression levels of genes involved in glycan-mediated post-translational modifications. Furthermore, thymol treatment reduced endogenous ergosterol content by decreasing the expression of ergosterol biosynthesis genes in a HOG MAPK pathway-dependent manner. Collectively, this study sheds light on the antifungal mechanisms of thymol against C. neoformans.

scholarly journals Wnt5A modulates integrin expression in a receptor-dependent manner in ovarian cancer cells

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vajihe Azimian-Zavareh ◽  
Zeinab Dehghani-Ghobadi ◽  
Marzieh Ebrahimi ◽  
Kian Mirzazadeh ◽  
Irina Nazarenko ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cell Proliferation ◽  
Cell Attachment ◽  
Ovarian Cancer Cells ◽  
Integrin Expression ◽  
Dependent Manner ◽  
Cancer Cell Proliferation ◽  
Expression Levels ◽  
Multicellular Aggregates ◽  
Focal Adhesion Kinase Activity

AbstractWnt5A signals through various receptors that confer versatile biological functions. Here, we used Wnt5A overexpressing human ovarian SKOV-3 and OVCAR-3 stable clones for assessing integrin expression, cell proliferation, migration, invasion, and the ability of multicellular aggregates (MCAs) formation. We found here, that Wnt5A regulates differently the expression of its receptors in the stable Wnt5A overexpressing clones. The expression levels of Frizzled (FZD)-2 and -5, were increased in different clones. However ROR-1, -2 expression levels were differently regulated in clones. Wnt5A overexpressing clones showed increased cell proliferation, migration, and clonogenicity. Moreover, Wnt5A overexpressing SKOV-3 clone showed increased MCAs formation ability. Cell invasion had been increased in OVCAR-3-derived clones, while this was decreased in SKOV-3-derived clone. Importantly, αv integrin expression levels were increased in all assessed clones, accompanied by increased cell attachment to fibronectin and focal adhesion kinase activity. Moreover, the treatment of clones with Box5 as a Wnt5A/FZD5 antagonist abrogates ITGAV increase, cell proliferation, migration, and their attachment to fibronectin. Accordingly, we observed significantly higher expression levels of ITGAV and ITGB3 in human high-grade serous ovarian cancer specimens and ITGAV correlated positively with Wnt5A in metastatic serous type ovarian cancer. In summary, we hypothesize here, that Wnt5A/FZD-5 signaling modulate αv integrin expression levels that could be associated with ovarian cancer cell proliferation, migration, and fibronectin attachment.

scholarly journals Resistance and Heteroresistance to Colistin in Pseudomonas aeruginosa Isolates from Wenzhou, China

2019 ◽  
Vol 63 (10) ◽  
Author(s):  
Jie Lin ◽  
Chunquan Xu ◽  
Renchi Fang ◽  
Jianming Cao ◽  
Xiucai Zhang ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Lipid A ◽  
Population Analysis ◽  
Colistin Resistance ◽  
Content Type ◽  
Maldi Tof Ms ◽  
Expression Levels ◽  
Maldi Tof ◽  
Broth Microdilution Method ◽  
Tof Ms

ABSTRACT The goal was to investigate the mechanisms of colistin resistance and heteroresistance in Pseudomonas aeruginosa clinical isolates. Colistin resistance was determined by the broth microdilution method. Colistin heteroresistance was evaluated by population analysis profiling. Time-kill assays were also conducted. PCR sequencing was performed to detect the resistance genes among (hetero)resistant isolates, and quantitative real-time PCR assays were performed to determine their expression levels. Pulsed-field gel electrophoresis and multilocus sequence typing were performed. Lipid A characteristics were determined via matrix-assisted laser desorption–ionization time of flight mass spectrometry (MALDI-TOF MS). Two resistant isolates and 9 heteroresistant isolates were selected in this study. Substitutions in PmrB were detected in 2 resistant isolates. Among heteroresistant isolates, 8 of 9 heteroresistant isolates had nonsynonymous PmrB substitutions, and 2 isolates, including 1 with a PmrB substitution, had PhoQ alterations. Correspondingly, the expression levels of pmrA or phoP were upregulated in PmrB- or PhoQ-substituted isolates. One isolate also found alterations in ParRS and CprRS. The transcript levels of the pmrH gene were observed to increase across all investigated isolates. MALDI-TOF MS showed additional 4-amino-4-deoxy-l-arabinose (l-Ara4N) moieties in lipid A profiles in (hetero)resistant isolates. In conclusion, both colistin resistance and heteroresistance in P. aeruginosa in this study mainly involved alterations of the PmrAB regulatory system. There were strong associations between mutations in specific genetic loci for lipid A synthesis and regulation of modifications to lipid A. The transition of colistin heteroresistance to resistance should be addressed in future clinical surveillance.

scholarly journals Neutrophil Extracellular Traps Exhibit Antibacterial Activity against Burkholderia pseudomallei and Are Influenced by Bacterial and Host Factors

2012 ◽  
Vol 80 (11) ◽  
pp. 3921-3929 ◽  
Author(s):  
Donporn Riyapa ◽  
Surachat Buddhisa ◽  
Sunee Korbsrisate ◽  
Jon Cuccui ◽  
Brendan W. Wren ◽  
...  
Keyword(s):  
Burkholderia Pseudomallei ◽  
Capsular Polysaccharide ◽  
Neutrophil Extracellular Traps ◽  
Polymorphonuclear Neutrophils ◽  
Dependent Manner ◽  
Predisposing Factor ◽  
Bacterial Killing ◽  
Content Type ◽  
Extracellular Traps ◽  
Type Iii Protein Secretion

ABSTRACTBurkholderia pseudomalleiis the causative pathogen of melioidosis, of which a major predisposing factor is diabetes mellitus. Polymorphonuclear neutrophils (PMNs) kill microbes extracellularly by the release of neutrophil extracellular traps (NETs). PMNs play a key role in the control of melioidosis, but the involvement of NETs in killing ofB. pseudomalleiremains obscure. Here, we showed that bactericidal NETs were released from human PMNs in response toB. pseudomalleiin a dose- and time-dependent manner.B. pseudomallei-induced NET formation required NADPH oxidase activation but not phosphatidylinositol-3 kinase, mitogen-activated protein kinases, or Src family kinase signaling pathways.B. pseudomalleimutants defective in the virulence-associated Bsa type III protein secretion system (T3SS) or capsular polysaccharide I (CPS-I) induced elevated levels of NETs. NET induction by such mutants was associated with increased bacterial killing, phagocytosis, and oxidative burst by PMNs. Taken together the data imply that T3SS and the capsule may play a role in evading the induction of NETs. Importantly, PMNs from diabetic subjects released NETs at a lower level than PMNs from healthy subjects. Modulation of NET formation may therefore be associated with the pathogenesis and control of melioidosis.

scholarly journals Potentiating Effect of Mandelate and Lactate on Chemically Induced Germination in Members of Bacillus cereus Sensu Lato

2017 ◽  
Vol 83 (24) ◽  
Author(s):  
Alistair H. Bishop
Keyword(s):  
Bacillus Cereus ◽  
Large Scale ◽  
Germination Rate ◽  
Dependent Manner ◽  
Clostridium Sporogenes ◽  
Specific Chemical ◽  
Content Type ◽  
Ph Range ◽  
Significant Discovery ◽  
The Impact

ABSTRACT Endospores of the genus Bacillus can be triggered to germinate by a limited number of chemicals. Mandelate had powerful additive effects on the levels and rates of germination produced in non-heat-shocked spores of Bacillus anthracis strain Sterne, Bacillus cereus, and Bacillus thuringiensis when combined with l-alanine and inosine. Mandelate had no germinant effect on its own but was active with these germinants in a dose-dependent manner at concentrations higher than 0.5 mM. The maximum rate and extent of germination were produced in B. anthracis by 100 mM l-alanine with 10 mM inosine; this was equaled by just 25% of these germinants when supplemented with 10 mM mandelate. Half the maximal germination rate was produced by 40% of the optimum germinant concentrations or 15% of them when supplemented with 0.8 mM mandelate. Germination rates in B. thuringiensis were highest around neutrality, but the potentiating effect of mandelate was maintained over a wider pH range than was germination with l-alanine and inosine alone. For all species, lactate also promoted germination in the presence of l-alanine and inosine; this was further increased by mandelate. Ammonium ions also enhanced l-alanine- and inosine-induced germination but only when mandelate was present. In spite of the structural similarities, mandelate did not compete with phenylalanine as a germinant. Mandelate appeared to bind to spores while enhancing germination. There was no effect when mandelate was used in conjunction with nonnutrient germinants. No effect was produced with spores of Bacillus subtilis, Clostridium sporogenes, or C. difficile. IMPORTANCE The number of chemicals that can induce germination in the species related to Bacillus cereus has been defined for many years, and they conform to specific chemical types. Although not a germinant itself, mandelate has a structure that is different from these germination-active compounds, and its addition to this list represents a significant discovery in the fundamental biology of spore germination. This novel activity may also have important applied relevance given the impact of spores of B. cereus in foodborne disease and B. anthracis as a threat agent. The destruction of spores of B. anthracis, for example, particularly over large outdoor areas, poses significant scientific and logistical problems. The addition of mandelate and lactate to the established mixtures of l-alanine and inosine would decrease the amount of the established germinants required and increase the speed and level of germination achieved. The large-scale application of “germinate to decontaminate” strategy may thus become more practicable.

Sign in / Sign up

Export Citation Format

Share Document