scholarly journals Actin filaments mediated root growth inhibition by changing their distribution under UV-B and hydrogen peroxide exposure in Arabidopsis

2020 ◽  
Vol 53 (1) ◽  
Author(s):  
Meiting Du ◽  
Yanhong Wang ◽  
Huize Chen ◽  
Rong Han
Keyword(s):  
Hydrogen Peroxide ◽  
Actin Filaments ◽  
Root Elongation ◽  
Root Tip ◽  
Root Growth Inhibition ◽  
Control Group ◽  
Dependent Manner ◽  
Elongation Zone ◽  
Wide Range ◽  
Root Morphogenesis

Abstract Background UV-B signaling in plants is mediated by UVR8, which interacts with transcriptional factors to induce root morphogenesis. However, research on the downstream molecules of UVR8 signaling in roots is still scarce. As a wide range of functional cytoskeletons, how actin filaments respond to UV-B-induced root morphogenesis has not been reported. The aim of this study was to investigate the effect of actin filaments on root morphogenesis under UV-B and hydrogen peroxide exposure in Arabidopsis. Results A Lifeact-Venus fusion protein was used to stain actin filaments in Arabidopsis. The results showed that UV-B inhibited hypocotyl and root elongation and caused an increase in H2O2 content only in the root but not in the hypocotyl. Additionally, the actin filaments in hypocotyls diffused under UV-B exposure but were gathered in a bundle under the control conditions in either Lifeact-Venus or uvr8 plants. Exogenous H2O2 inhibited root elongation in a dose-dependent manner. The actin filaments changed their distribution from filamentous to punctate in the root tips and mature regions at a lower concentration of H2O2 but aggregated into thick bundles with an abnormal orientation at H2O2 concentrations up to 2 mM. In the root elongation zone, the actin filament arrangement changed from lateral to longitudinal after exposure to H2O2. Actin filaments in the root tip and elongation zone were depolymerized into puncta under UV-B exposure, which showed the same tendency as the low-concentration treatments. The actin filaments were hardly filamentous in the maturation zone. The dynamics of actin filaments in the uvr8 group under UV-B exposure were close to those of the control group. Conclusions The results indicate that UV-B inhibited Arabidopsis hypocotyl elongation by reorganizing actin filaments from bundles to a loose arrangement, which was not related to H2O2. UV-B disrupted the dynamics of actin filaments by changing the H2O2 level in Arabidopsis roots. All these results provide an experimental basis for investigating the interaction of UV-B signaling with the cytoskeleton.

scholarly journals Hyper, a Hydrogen Peroxide Sensor, Indicates the Sensitivity of the Arabidopsis Root Elongation Zone to Aluminum Treatment

Sensors ◽  
2015 ◽  
Vol 15 (1) ◽  
pp. 855-867 ◽  
Author(s):  
Alejandra Hernández-Barrera ◽  
Ana Velarde-Buendía ◽  
Isaac Zepeda ◽  
Federico Sanchez ◽  
Carmen Quinto ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Root Elongation ◽  
Elongation Zone ◽  
Arabidopsis Root ◽  
Hydrogen Peroxide Sensor

scholarly journals Effects of hydrogen peroxide on diazepam and xylazine sedation in chicks

2012 ◽  
Vol 5 (4) ◽  
pp. 179-183 ◽  
Author(s):  
Yaareb J. Mousa ◽  
Fouad K. Mohammad
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Recovery Time ◽  
Tap Water ◽  
Statistical Significance ◽  
Control Group ◽  
Dependent Manner ◽  
Water Control ◽  
Whole Brain ◽  
Total Recovery

ABSTRACT Oxidative stress may cause various neuronal dysfunctions and modulate responses to many centrally acting drugs. This study examines the effects of oxidative stress produced by hydrogen peroxide (H2O2) on sedation induced by diazepam or xylazine as assessed in 7-14 day-old chicks. Day-old chicks were provided with either plane tap water (control group) or H2O2 in tap water as 0.5% v/v drinking solution for two weeks in order to produce oxidative stress. Spectrophotometric methods were used to determine glutathione and malondialdehyde concentrations in plasma and whole brain. Drug-induced sedation in the chicks was assessed by monitoring the occurrence of signs of sedation manifested as drooping of the head, closed eyelids, reduced motility or immotility, decreased distress calls, and recumbency. The latency to onset of sedation and its duration were also recorded. H2O2 treatment for two weeks significantly decreased glutathione and increased malondialdehyde concentrations in plasma and whole brain of the chicks on days 7, 10 and 14 as compared with respective age-matched control groups. H2O2 decreased the median effective doses of diazepam and xylazine for the induction of sedation in chicks by 46% and 63%, respectively. Injection of diazepam at 2.5, 5 and 10 mg/kg, i.m. or xylazine at 2, 4 and 8 mg/kg, i.m. induced sedation in both control and H2O2-treated chicks in a dose dependent manner, manifested by the above given signs of sedation. H2O2 significantly decreased the latency to onset of sedation in chicks treated with diazepam at 5 and 10 mg/kg, increased the duration of sedation and prolonged the total recovery time in comparison with respective non-stressed control chicks. A similar trend occurred with xylazine in the H2O2-treated chicks, though the differences from control counterparts did not attain the statistical significance, except for the recovery time of the lowest dose of the drug. The data suggest that H2O2-induced oxidative stress sensitizes the chicks to the depressant action of the sedatives diazepam and xylazine. Further studies are needed to examine the potential role of oxidative stress in modulating the actions of therapeutic agents on the brain.

scholarly journals Haemostatic Effects of Ethanolic Extracts of Amaranthus hybridus on Wistar Rats

2020 ◽  
pp. 14-21
Author(s):  
B. C. Chinko ◽  
F. S. Amah-Tariah
Keyword(s):  
Platelet Count ◽  
Prothrombin Time ◽  
Partial Thromboplastin Time ◽  
Wistar Rats ◽  
Activated Partial Thromboplastin Time ◽  
Control Group ◽  
Dependent Manner ◽  
Amaranthus Hybridus ◽  
Wide Range ◽  
Ethanolic Extracts

Introduction: Haemostasis refers to the arrest of bleeding due to vascular damage and involves the intrinsic and extrinsic coagulation pathways which converge at the point of fibrin activation to stop or minimize blood loss. Amaranthus hybridus contains a while range of nutritional, chemical and phytochemical constituents which gives it wide range of applications in folk medicine. Aim: To evaluate the effects of ethanolic extracts of Amaranthus hybridus on blood platelet count, prothrombin time (PT) and activated partial thromboplastin time (APTT) using Wistar rat models. Methodology: Twenty Four (24) adult male Wistar rats were used for the study. The animals were randomly divided into three (3) groups of eight (8) animals each. Oral administration of distilled water for the control group and ethanolic extracts of Amaranthus hybridus at 30 and 60 mg/kg lasted for twenty eight (28) days. Platelet count, prothrombin time (PT) and activated partial thromboplastin time (APTT) were determined using standard laboratory methods. Results: Ethanolic extracts of Amaranthus hybridus significantly increased platelet count at 30 mg and 60 mg/kg compared to the control animals (p<0.05). Also, it significantly reduced prothrombin time and activated partial thromboplastin time at 30 and 60 mg/kg in a dose dependent manner compared to control animals (P<0.05).   Conclusion: The study shows that ethanolic extract of Amaranthus hybridus may have enhanced haemostasis as demonstrated by increased platelet count and reduced prothrombin (PT) and activated partial thromboplastin time (APTT) time.

Effect of Turmeric and Ginger on Lipid Profile in Male Rats Exposed to Oxidative Stress

2019 ◽  
Vol 10 (01) ◽  
Author(s):  
Eman A. Al-Rekabi ◽  
Dheyaa K. Alomer ◽  
Rana Talib Al-Muswie ◽  
Khalid G. Al-Fartosi
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Drinking Water ◽  
Lipid Profile ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Male Rats ◽  
Control Group ◽  
Very Low Density Lipoprotein ◽  
Low Density

The present study aimed to investigate the effect of turmeric and ginger on lipid profile of male rats exposed to oxidative stress induced by hydrogen peroxide H2O2 at a concentration of 1% given with consumed drinking water to male rats. Methods: 200 mg/kg from turmeric and ginger were used, and the animals were treatment for 30 days. Results: the results showed a significant increase in cholesterol, triglycerides, low density lipoprotein (LDL), very low density lipoprotein (VLDL), whereas it explained a significant decrease in high density lipoprotein (HDL) of male rats exposed to oxidative stress when compared with control group. the results showed a significant decrease in cholesterol, triglycerides, (LDL), (VLDL), whereas it explained a significant increase in (HDL) of rats treated with turmeric and ginger at dose 200 mg/kg when compared with male rats exposed to oxidative stress.

Antimicrobial Effect of 940 nm Diode Laser based on Photolysis of Hydrogen Peroxide in the Treatment of Periodontal Disease

2018 ◽  
Vol 69 (8) ◽  
pp. 2081-2088 ◽  
Author(s):  
Alin Alexandru Odor ◽  
Edwin Sever Bechir ◽  
Deborah Violant ◽  
Victoria Badea
Keyword(s):  
Hydrogen Peroxide ◽  
Laser Therapy ◽  
Diode Laser ◽  
Antimicrobial Effect ◽  
The Other ◽  
Control Group ◽  
Group 4 ◽  
Periodontal Bacteria ◽  
Severe Periodontitis ◽  
Before And After

Moderate and severe periodontitis represents a challenge in the non-surgical periodontal therapy. Due to the lack of evidence regarding the antimicrobial effectiveness of 940 nm diode laser in periodontal treatment, this study aimed to evaluate the antimicrobial effect of hydrogen peroxide (H2O2) photolysis performed with 940 nm diode laser in the treatment of moderate and severe periodontitis. Twenty-five patients with 100 teeth were selected for this pilot study. The test teeth were randomly assigned to one of the four treatment groups: Group 1: scaling and root planning (SRP) (control group); and the following experimental groups: Group 2: H2O2; Group 3: 940 nm diode laser therapy; Group 4: 940 nm diode laser therapy and H2O2. Clinical examinations, like probing depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) were performed before and after the treatment. The microbiological evaluation, effectuated before and after the treatment, included nine periodontal bacteria species and investigated by means of real-time PCR assay. The clinical and bacterial differences in the tested groups, was assessed between control group and the other three experimental groups, as well as between the experimental groups. The total bacteria load was reduced for all four studied groups. Group 4 (diode laser + H2O2) showed significant bacterial reduction of the major periodontal bacteria like Pg., Tf., Td., Pi., Pm., Fn (p[0.001) than the other 3 groups (p]0.001). Also the periodontal clinical parameters, like PD, CAL and BOP showed a significant reduction after the photolysis of H2O2 with the 940 nm diode laser (p[0.001). Differences between tested groups showed a significant beneficial results in regard to Group 4.It is suggested that the photoactivation of H2O2 with the 940 nm diode laser can be used successfully in adjunctive to the non-surgical periodontal treatment as a bactericidal tool.

The Toxicity Effect of Echium Amoenum on the Liver and Kidney of Mice.

2020 ◽  
Vol 17 ◽  
Author(s):  
Mozhgan Ghorbani ◽  
Atefeh Araghi ◽  
Nabi Shariatifar ◽  
Seyed Hooman Mirbaha ◽  
Behrokh Marzban Abbasabadi ◽  
...  
Keyword(s):  
Pyrrolizidine Alkaloids ◽  
Biochemical Analysis ◽  
Liver Enzymes ◽  
Copper Ion ◽  
Control Group ◽  
Dependent Manner ◽  
Toxicity Effect ◽  
Significant Difference ◽  
Liver And Kidney ◽  
Echium Amoenum

Aims: The aim of this study was to investigate the toxic effect of Echium amoenum plants on the liver and kidney of animal model. Background: Echium amoenum is one of the medicinal plants containing pyrrolizidine alkaloids with several properties which has widely consumed among different communities. Objective: The toxic effects of Echium amoenum on the liver and kidney were investigated in this study. Methods: Sixty mice were kept for 28 days under the appropriate laboratory conditions. Echium amoenum extract (25, 12.5, 50 mg / kg, ip.) was administered for 28 days. At the end of experiment, blood samples were drawn and liver and kidneys were removed for evaluating hepatotoxicity and nephrotoxicity of extract. Additionally, experiments were conducted to assay the enzymatic and oxidative activities. Results: There was no significant difference in the levels of copper ion in the liver and kidneys among all groups. There was a significant difference in the levels of lipid peroxidation in the liver of treated groups versus control group. The significant difference was not observed in the levels of glutathione of the liver of all groups. However, the levels of glutathione of the kidney significantly decreased in the treated groups versus control group. There was no significant difference in the liver enzymes including ALP, SGOT, and SGPT between all groups. This indicates that damage increase with enhancing the time and concentrations of extract. Biochemical analysis showed the creatinine and urea levels did not change in the treated groups versus control group. Conclusion: According to the present findings, it is suggested that Echium amoenum causes hepatotoxicity and nephrotoxicity effects in dose and time dependent manner.

Ethanol Extract of Achillea fragrantissima Enhances Angiogenesis through Stimulation of VEGF Production

2020 ◽  
Vol 21 ◽  
Author(s):  
Hana M. Hammad ◽  
Amer Imraish ◽  
Maysa Al-Hussaini ◽  
Malek Zihlif ◽  
Amani A. Harb ◽  
...  
Keyword(s):  
Wound Healing ◽  
Rural Communities ◽  
Ex Vivo ◽  
Ethanol Extract ◽  
Aortic Ring ◽  
Treated Group ◽  
Control Group ◽  
Dependent Manner ◽  
Achillea Fragrantissima

Objective: Achillea fragrantissima L. (Asteraceae) is a traditionally used medicinal herb in the rural communities of Jordan. Methods: The present study evaluated the efficacy of the ethanol extract of this species on angiogenesis in both, ex vivo using rat aortic ring assay and in vivo using rat excision wound model. Results: In concentrations of 50 and 100 µg/ml, the ethanol extract showed angiogenic stimulatory effect and significantly increased length of capillary protrusions around aorta rings of about 60% in comparison to those of untreated aorta rings. In MCF-7 cells, the ethanol extract of A. fragrantissima stimulates the production of VEGF in a dose-dependent manner. 1% and 5% of ethanol extract of A. fragrantissima containing vaseline based ointment was applied on rat excision wounds for six days and was found to be effective in wound healing and maturation of the scar. Both preparations resulted in better wound healing when compared to the untreated control group and vaseline-treated group. This effect was comparable to that induced by MEBO, the positive control. Conclusion: The results indicate that A. fragrantissima has a pro-angiogenic effect, which may act through the VEGF signaling pathway.

Histochemical Examination of Invertase Activities in the Growing Tip of the Plant Root

2017 ◽  
Vol 10 (1) ◽  
pp. 35-45
Author(s):  
N.F. Lunkova ◽  
N.A. Burmistrova ◽  
M.S. Krasavina
Keyword(s):  
Plant Root ◽  
Invertase Activity ◽  
Root Tip ◽  
Elongation Zone ◽  
Root Tips ◽  
Phloem Unloading ◽  
Meristem Cell ◽  
Transition To Elongation ◽  
Different Tissues

Background:A growing part of the root is one of the most active sinks for sucrose coming from source leaves through the phloem. In the root, sucrose is unloaded from conducting bundles and is distributed among the surrounding cells. To be involved in the metabolism, sucrose should disintegrate into hexoses by means of degrading enzymes.Aims:The aim of this research was to explore the possibility of the involvement of one such enzymes, invertase, in phloem unloading as well as distribution of its activity in the functionally different tissues of the plant root tips.Method:To estimate the enzyme activities in root tissues, we applied two techniques: the histochemical method using nitro blue tetrazolium. The localization of phloem unloading was studied with carboxyfluorescein, a fluorescent marker for symplastic transport.Results:Invertase activity was not detected in the apical part of the meristem. It appeared only between the basal part of this zone and the beginning of the elongation zone. There is the root phloem unloading in that area. Invertase activity increased with increasing the distance from the root tip and reached the highest values in the region of cell transition to elongation and in the elongation zone. The activities of the enzyme varied in different tissues of the same zone and sometimes in the neighboring cells of the same tissue. Biochemical determination of invertase activity was made in the maize root segments coincident to the zones of meristem, cell elongation and differentiation. The results of both methods of determination of invertase activity were in agreement.Conclusion:It was concluded that phloem unloading correlated with invertase activity, possibly because of the activation of invertase by unloaded sucrose. Invertase is one of the factors involved in the processes preparing the cells for their transition to elongation because the concentration of osmotically active hexoses increases after cleavage of sucrose, that stimulates water entry into the cells, which is necessary for elongation growth.

scholarly journals A Bacterial Tower of Babel: Quorum-Sensing Signaling Diversity and Its Evolution

2020 ◽  
Vol 74 (1) ◽  
pp. 587-606 ◽  
Author(s):  
Nitzan Aframian ◽  
Avigdor Eldar
Keyword(s):  
Quorum Sensing ◽  
Social Interactions ◽  
Signal Molecules ◽  
Allelic Polymorphism ◽  
Dependent Manner ◽  
Tower Of Babel ◽  
Cognate Receptor ◽  
Wide Range ◽  
Family Code ◽  
Bacterial Groups

Quorum sensing is a process in which bacteria secrete and sense a diffusible molecule, thereby enabling bacterial groups to coordinate their behavior in a density-dependent manner. Quorum sensing has evolved multiple times independently, utilizing different molecular pathways and signaling molecules. A common theme among many quorum-sensing families is their wide range of signaling diversity—different variants within a family code for different signal molecules with a cognate receptor specific to each variant. This pattern of vast allelic polymorphism raises several questions—How do different signaling variants interact with one another? How is this diversity maintained? And how did it come to exist in the first place? Here we argue that social interactions between signaling variants can explain the emergence and persistence of signaling diversity throughout evolution. Finally, we extend the discussion to include cases where multiple diverse systems work in concert in a single bacterium.

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