scholarly journals Carbon Sources for Yeast Growth as a Precondition of Hydrogen Peroxide Induced Hormetic Phenotype

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Ruslana Vasylkovska ◽  
Natalia Petriv ◽  
Halyna Semchyshyn
Keyword(s):  
Hydrogen Peroxide ◽  
Growth Medium ◽  
Carbon Sources ◽  
Carbon Substrate ◽  
Dependent Manner ◽  
Yeast Growth ◽  
Concentration Dependent Manner ◽  
Reproductive Ability ◽  
The Relationship ◽  
Hormetic Response

Hormesis is a phenomenon of particular interest in biology, medicine, pharmacology, and toxicology. In this study, we investigated the relationship between H2O2-induced hormetic response inS. cerevisiaeand carbon sources in yeast growth medium. In general, our data indicate that (i) hydrogen peroxide induces hormesis in a concentration-dependent manner; (ii) the effect of hydrogen peroxide on yeast reproductive ability depends on the type of carbon substrate in growth medium; and (iii) metabolic and growth rates as well as catalase activity play an important role in H2O2-induced hormetic response in yeast.

scholarly journals Involvement of Catalase in Saccharomyces Cerevisiae Hormetic Response to Hydrogen Peroxide

2015 ◽  
Vol 2 (1) ◽  
pp. 107-114 ◽  
Author(s):  
Ruslana Vasylkovska ◽  
Nadia Burdylyuk ◽  
Halyna Semchyshyn
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Hydrogen Peroxide ◽  
Stress Response ◽  
Catalase Activity ◽  
Colony Growth ◽  
Time Dependent ◽  
Dependent Manner ◽  
Induced Stress ◽  
The Relationship ◽  
Hormetic Response

In this study, we investigated the relationship between catalase activity and H2O2-induced hormetic response in budding yeast S. cerevisiae. In general, our data suggest that: (i)hydrogen peroxide induces hormesis in a concentration- and time-dependent manner; and (ii) theeffect of hydrogen peroxide on yeast colony growth positively correlates with the activity ofcatalase that suggests the enzyme involvement in overall H2O2-induced stress response andhormetic response in yeast.

Comparative Effects of Bupivacaine and Ropivacaine on Intracellular Calcium Transients and Tension in Ferret Ventricular Muscle

2004 ◽  
Vol 101 (4) ◽  
pp. 888-894 ◽  
Author(s):  
Yasushi Mio ◽  
Norio Fukuda ◽  
Yoichiro Kusakari ◽  
Yoshikiyo Amaki ◽  
Yasumasa Tanifuji ◽  
...  
Keyword(s):  
Inhibitory Effect ◽  
Bay K 8644 ◽  
Clinical Settings ◽  
Ca Channel ◽  
Dependent Manner ◽  
Inhibitory Effects ◽  
Concentration Dependent Manner ◽  
Intracellular Ca ◽  
Slope Difference ◽  
The Relationship

Background Recent evidence suggests that ropivacaine exerts markedly less cardiotoxicity compared with bupivacaine; however, the mechanisms are not fully understood at the molecular level. Methods Isolated ferret ventricular papillary muscles were microinjected with the Ca-binding photoprotein aequorin, and intracellular Ca transients and tension were simultaneously measured during twitch in the absence and presence of bupivacaine or ropivacaine. Results Bupivacaine and ropivacaine (10, 30, and 100 microm) reduced peak systolic [Ca]i and tension in a concentration-dependent manner. The effects were significantly greater for bupivacaine, particularly on tension (approximately twofold). The percentage reduction of tension was linearly correlated with that of [Ca]i for both anesthetics, with the slope of the relationship being approximately equal to 1.0 for ropivacaine and approximately equal to 1.3 for bupivacaine (slope difference, P < 0.05), suggesting that the cardiodepressant effect of ropivacaine results predominantly from inhibition of Ca transients, whereas bupivacaine suppresses Ca transients and the reaction beyond Ca transients, i.e., myofibrillar activation, as well. BAY K 8644, a Ca channel opener, abolished the inhibitory effects of ropivacaine on Ca transients and tension, whereas BAY K 8644 only partially inhibited the effects of bupivacaine, particularly the effects on tension. Conclusion The cardiodepressant effect of bupivacaine is approximately twofold greater than that of ropivacaine. Bupivacaine suppresses Ca transients more markedly than does ropivacaine and reduces myofibrillar activation, which may at least in part underlie the greater inhibitory effect of bupivacaine on cardiac contractions. These results suggest that ropivacaine has a more favorable profile as a local anesthetic in the clinical settings.

scholarly journals Antiglycation Activity of Iridoids and Their Food Sources

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Brett J. West ◽  
Akemi Uwaya ◽  
Fumiyuki Isami ◽  
Shixin Deng ◽  
Sanae Nakajima ◽  
...  
Keyword(s):  
Pilot Study ◽  
Food Sources ◽  
Dependent Manner ◽  
Skin Autofluorescence ◽  
Open Label ◽  
Concentration Dependent Manner ◽  
Cross Sectional ◽  
Glycation End Products ◽  
The Relationship

Iridoids are dietary phytochemicals that may have the ability to inhibit the formation of advanced glycation end products (AGEs). Three studies were conducted to investigate this anti-AGE potential. First, the inhibition of fluorescence intensity by food-derived iridoids, after 4 days of incubation with bovine serum albumin, glucose, and fructose, was used to evaluatein vitroantiglycation activity. Next, an 8-week open-label pilot study used the AGE Reader to measure changes in the skin autofluorescence of 34 overweight adults who consumed daily a beverage containing food sources of iridoids. Finally, a cross-sectional population study with 3913 people analyzed the relationship between daily iridoid intake and AGE accumulation, as measured by skin autofluorescence with the TruAge scanner. In thein vitrotest, deacetylasperulosidic acid and loganic acid both inhibited glycation in a concentration-dependent manner, with respective IC50values of 3.55 and 2.69 mM. In the pilot study, average skin autofluorescence measurements decreased by 0.12 units (P<0.05). The cross-sectional population survey revealed that, for every mg of iridoids consumed, there is a corresponding decline in AGE associated age of 0.017 years (P<0.0001). These results suggest that consumption of dietary sources of iridoids may be a useful antiaging strategy.

scholarly journals Free Radical Scavenging Capacities and Alleviating Actions of Polysaccharides Extract of Termitomyces le-testui on Methylprednisolone-Induced Immunodepression in Rats

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Foncham Evans Ngwenah ◽  
Kada Sanda Antoine ◽  
Salah Martin ◽  
Tume Christopher ◽  
Oumar Mahamat
Keyword(s):  
Hydrogen Peroxide ◽  
Free Radical ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Hot Water ◽  
Phagocytic Index ◽  
Dependent Manner ◽  
Scavenging Activity ◽  
Concentration Dependent Manner ◽  
Crude Polysaccharide

Background. Natural products have been said to show immunomodulatory and antioxidant activities. The research study was aimed to assess the immunomodulatory and free radical scavenging activities of crude polysaccharide from dry mushroom fruiting bodies of Termitomyces le-testui. Materials and Methods. Hot water extract of polysaccharide extract of T. le-testui was prepared and tested in white albino Wister rats for its immunomodulatory activities effect on methylprednisolone-immunosuppressed animals. In addition, the radical scavenging activity of the polysaccharide was evaluated using nitrite and hydrogen peroxide. Results. The result of the study showed that the polysaccharide T. le-testui increases the phagocytic index, energy metabolism of macrophages, spleen index, and nitric oxide in a concentration-dependent manner in immunosuppressed animals. Also, it was observed that the extract increased dose-dependent total oxidative stress and thymus index. Finally, the crude polysaccharide-rich extract showed nitrite and hydrogen peroxide scavenging activity in a concentration-dependent manner. Conclusion. Polysaccharide-rich extract possesses immunomodulatory and antioxidant properties.

scholarly journals Rosmarinic Acid Alleviates the Endothelial Dysfunction Induced by Hydrogen Peroxide in Rat Aortic Rings via Activation of AMPK

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Hui Zhou ◽  
Baocai Fu ◽  
Bo Xu ◽  
Xiangquan Mi ◽  
Gang Li ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Endothelial Dysfunction ◽  
Rosmarinic Acid ◽  
Dependent Manner ◽  
Vascular Events ◽  
Concentration Dependent Manner ◽  
Obvious Effect ◽  
Beneficial Effects ◽  
Compound C

Endothelial dysfunction is the key player in the development and progression of vascular events. Oxidative stress is involved in endothelial injury. Rosmarinic acid (RA) is a natural polyphenol with antioxidative, antiapoptotic, and anti-inflammatory properties. The present study investigates the protective effect of RA on endothelial dysfunction induced by hydrogen peroxide (H2O2). Compared with endothelium-denuded aortic rings, the endothelium significantly alleviated the decrease of vasoconstrictive reactivity to PE and KCl induced by H2O2. H2O2 pretreatment significantly injured the vasodilative reactivity to ACh in endothelium-intact aortic rings in a concentration-dependent manner. RA individual pretreatment had no obvious effect on the vasoconstrictive reaction to PE and KCl, while its cotreatment obviously mitigated the endothelium-dependent relaxation impairments and the oxidative stress induced by H2O2. The RA cotreatment reversed the downregulation of AMPK and eNOS phosphorylation induced by H2O2 in HAEC cells. The pretreatment with the inhibitors of AMPK (compound C) and eNOS (L-NAME) wiped off RA’s beneficial effects. All these results demonstrated that RA attenuated the endothelial dysfunction induced by oxidative stress by activating the AMPK/eNOS pathway.

A study of the in vitro clinical interaction between lidocaine and premedications using rat liver microsomes

2002 ◽  
Vol 21 (8) ◽  
pp. 453-456 ◽  
Author(s):  
A Nagashima ◽  
E Tanaka ◽  
S Inomata ◽  
S Misawa
Keyword(s):  
Liver Microsomes ◽  
Competitive Inhibitor ◽  
Rat Liver Microsomes ◽  
Dependent Manner ◽  
Potential Importance ◽  
Concentration Dependent Manner ◽  
Hepatic Microsomes ◽  
The Relationship ◽  
Substrate Concentrations

In this study, we have investigated the relationship between lidocaine metabolism and premedication, i.e., psychotropic and anti-anxiety agents (diazepam, midazolam), hypnotics (pentobarbital, thiamylal), depolarizing muscular relaxants (vecuronium, pancuronium and suxamethonium), an active anti-hypertensive (clonidine) and an H2 receptor antagonist (cimetidine) using rat hepatic microsomes in vitro. Lidocaine metabolism was noncompetitively inhibited by midazolam (Ki=29.0 mM). Thilamylal was a moderate competitive inhibitor of lidocaine metabolism (Ki=77.8 mM). Pentobarbital, diazepam and cimetidine weakly inhibited lidocaine metabolism formation in a concentration-dependent manner at high substrate concentrations. On the other hand, vecuronium, pancuronium, suxamethonium and clonidine did not inhibit lidocaine metabolism over the therapeutic range. These results show that the interaction between lidocaine and midazolam and thiamylal, catalyzed by a similar cytochrome P450, is of potential importance in toxicological and clinical studies.

scholarly journals Diversity in Antistaphylococcal Mechanisms among Membrane-Targeting Antimicrobial Peptides

2001 ◽  
Vol 69 (8) ◽  
pp. 4916-4922 ◽  
Author(s):  
Su-Pin Koo ◽  
Arnold S. Bayer ◽  
Michael R. Yeaman
Keyword(s):  
Antimicrobial Peptides ◽  
Cytoplasmic Membrane ◽  
Membrane Permeabilization ◽  
Dependent Manner ◽  
Quantitative Culture ◽  
Cell Permeabilization ◽  
Concentration Dependent Manner ◽  
Gramicidin D ◽  
Platelet Microbicidal Protein ◽  
The Relationship

ABSTRACT Many antimicrobial peptides permeabilize the bacterial cytoplasmic membrane. However, it is unclear how membrane permeabilization and antimicrobial activity are related for distinct peptides. This study investigated the relationship between Staphylococcus aureusmembrane permeabilization and cell death due to the following antistaphylococcal peptides: thrombin-induced platelet microbicidal protein 1 (tPMP-1), gramicidin D, and protamine. Isogenic S. aureus strains ISP479C and ISP479R (tPMP-1 susceptible and resistant, respectively), were loaded with the fluorochrome calcein and exposed to a range of concentrations of each peptide. Flow cytometry was then used to monitor membrane permeabilization by quantifying the release of preloaded calcein. Killing was determined by quantitative culture at time points simultaneous to measurement of membrane permeabilization. Membrane permeabilization and killing caused by tPMP-1 occurred in a time- and concentration-dependent manner, reflecting the intrinsic tPMP-1 susceptibilities of ISP479C and ISP479R. In comparison, gramicidin D killed both S. aureusstrains to equivalent extents in a concentration-dependent manner between 0.5 to 50 μg/ml, but cell permeabilization only occurred at the higher peptide concentrations (25 and 50 μg/ml). Protamine permeabilized, but did not kill, either strain at concentrations up to 10 mg/ml. Regression analyses revealed different relationships between membrane permeabilization and staphylocidal activity for the distinct antimicrobial peptides. Taken together, these findings demonstrate that permeabilization, per se, does not invariably result in staphylococcal death due to distinct antimicrobial peptides. Thus, although each of these peptides interacts with the S. aureus cytoplasmic membrane, diversity exists in their mechanisms of action with respect to the relationship between membrane permeabilization and staphylocidal activity.

scholarly journals In vitro antidiabetic, anti-inflammatory and antioxidant potential of the ethanol extract of Uromastyx hardwickii skin

2021 ◽  
Vol 18 (10) ◽  
pp. 2109-2115
Author(s):  
Waqas Ahmad Shams ◽  
Gauhar Rehman ◽  
Samuel Okwudili Onoja ◽  
Abid Ali ◽  
Khurshaid Khan ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Glucose Uptake ◽  
Ethanol Extract ◽  
Antioxidant Potential ◽  
Yeast Cells ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Anti Inflammatory

Purpose: To evaluate the in vitro antidiabetic, anti-inflammatory and antioxidant potential of the ethanol extract of Uromastyx hardwickii Skin (UHSEE). Methods: The in vitro effects of UHSEE at various concentrations (10 - 250 µg/mL) on the activities of ߙ-amylase, ߙ-glucosidase and glucose uptake by yeast cells were used to evaluate its antidiabetic potential. Nitric oxide (NO), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide inhibitory assay were employed to determine its antioxidant effects, while the anti-inflammatory effects were evaluated using human red blood cell (HRBC) membrane stabilization assay. Results: UHSEE inhibited ߙ-amylase and ߙ-glucosidase enzymes but increased glucose uptake by yeast cells in a concentration-dependent manner (p < 0.05). It also inhibited NO, DPPH, hydrogen peroxide and HRBC hemolysis in a concentration-dependent manner (p < 0.05). Conclusion: Uromastyx hardwickii skin exhibits promising good antidiabetic, antioxidant and antiinflammatory properties in vitro. However, its true potentials in this regard needs to be evaluted in vivo.

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