scholarly journals Physiological Dose of EGCG Attenuates the Health Defects of High Dose by Regulating MEMO-1 in Caenorhabditis elegans

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Yan Lu ◽  
Yi Wang ◽  
Li-gui Xiong ◽  
Jian-an Huang ◽  
Zhong-hua Liu ◽  
...  
Keyword(s):  
Nadph Oxidase ◽  
Body Movement ◽  
Feedback Signal ◽  
Protective Mechanism ◽  
High Dose ◽  
Pumping Rate ◽  
Dietary Polyphenols ◽  
Reduced Body ◽  
Physiological Dose

EGCG, as a dietary-derived antioxidant, has been extensively studied for its beneficial health effects. Nevertheless, it induces the transient increase in ROS and leads to the hormetic extension of lifespan. How exactly biology-benefiting effects with the minimum severe adverse are realized remains unclear. Here, we showed that physiological dose of EGCG could help moderate remission in health side effects exposed to high doses, including shortened lifespan, reduced body size, decreased pharyngeal pumping rate, and dysfunctional body movement in C. elegans. Furthermore, we found this result was caused by the physiological dose of EGCG to block the continued ROS accumulation and triggered acclimation responses after stressor removal. Also, in this process, we observed that EGCG downregulated the key redox protein MEMO-1 to activate the feedback loop of NADPH oxidase-mediated redox signaling. Our data indicates that the feedback signal induced by NADPH oxidase may contribute to the health-protective mechanism of dietary polyphenols in vivo.

scholarly journals Erythropoietin regulates POMC expression via STAT3 and potentiates leptin response

2015 ◽  
Vol 56 (2) ◽  
pp. 55-67 ◽  
Author(s):  
Soumyadeep Dey ◽  
Xiaoxia Li ◽  
Ruifeng Teng ◽  
Mawadda Alnaeeli ◽  
ZhiYong Chen ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
Culture System ◽  
Arcuate Nucleus ◽  
Ex Vivo ◽  
High Dose ◽  
Reduced Body ◽  
Stat3 Signaling ◽  
Stat3 Phosphorylation ◽  
Neural Cultures

The arcuate nucleus of the hypothalamus is essential for metabolic homeostasis and responds to leptin by producing several neuropeptides including proopiomelanocortin (POMC). We previously reported that high-dose erythropoietin (Epo) treatment in mice while increasing hematocrit reduced body weight, fat mass, and food intake and increased energy expenditure. Moreover, we showed that mice with Epo receptor (EpoR) restricted to erythroid cells (ΔEpoRE) became obese and exhibited decreased energy expenditure. Epo/EpoR signaling was found to promote hypothalamus POMC expression independently from leptin. Herein we used WT and ΔEpoREmice and hypothalamus-derived neural culture system to study the signaling pathways activated by Epo in POMC neurons. We show that Epo stimulation activated STAT3 signaling and upregulated POMC expression in WT neural cultures. ΔEpoREmice hypothalamus showed reduced POMC levels and lower STAT3 phosphorylation, with and without leptin treatment, compared toin vivoandex vivoWT controls. Collectively, these data show that Epo regulates hypothalamus POMC expression via STAT3 activation, and provide a previously unrecognized link between Epo and leptin response.

scholarly journals Determination of lumefantrine as an effective drug against Toxoplasma gondii infection – in vitro and in vivo study

Parasitology ◽  
2020 ◽  
pp. 1-7
Author(s):  
Dawei Wang ◽  
Mengen Xing ◽  
Saeed El-Ashram ◽  
Yingying Ding ◽  
Xiao Zhang ◽  
...  
Keyword(s):  
Side Effects ◽  
Toxoplasma Gondii ◽  
Parasite Burden ◽  
Vero Cells ◽  
Negative Control ◽  
Protective Mechanism ◽  
High Dose ◽  
Mouse Tissues

Abstract Toxoplasma gondii is an obligate intracellular protozoan parasite, which can infect almost all warm-blooded animals, including humans, leading to toxoplasmosis. Currently, the effective treatment for human toxoplasmosis is the combination of sulphadiazine and pyrimethamine. However, both drugs have serious side-effects and toxicity in the host. Therefore, there is an urgent need for the discovery of new anti-T. gondii drugs with high potency and less or no side-effects. Our findings suggest that lumefantrine exerts activity against T. gondii by inhibiting its proliferation in Vero cells in vitro without being toxic to Vero cells (P ≤ 0.01). Lumefantrine prolonged mice infected with T. gondii from death for 3 days at the concentration of 50 μg L−1 than negative control (phosphate-buffered saline treated only), and reduced the parasite burden in mouse tissues in vivo (P ≤ 0.01; P ≤ 0.05). In addition, a significant increase in interferon gamma (IFN-γ) production was observed in high-dose lumefantrine-treated mice (P ≤ 0.01), whereas interleukin 10 (IL-10) and IL-4 levels increased in low-dose lumefantrine-treated mice (P ≤ 0.01). The results demonstrated that lumefantrine may be a promising agent to treat toxoplasmosis, and more experiments on the protective mechanism of lumefantrine should be undertaken in further studies.

scholarly journals Curcumin a Multifaceted Compound with Hormetic Behaviour that Mediates an Intricate Crosstalk between Mitochondrial Biogenesis, Mitophagy, Mitophagic Death and Apoptosis

2017 ◽  
Author(s):  
Nathan Earl Rainey ◽  
Aoula Moustapha ◽  
Raphaelle Parker ◽  
Patrice Xavier Petit
Keyword(s):  
Cell Death ◽  
Mitochondrial Biogenesis ◽  
Calcium Release ◽  
Mitochondrial Outer Membrane ◽  
Protective Mechanism ◽  
High Dose ◽  
M Cell ◽  
Mitochondrial Outer Membrane Permeabilization

Curcumin, found in the rhizome of turmeric, has extensive therapeutic promises via its antioxidant, anti-inflammatory, and antiproliferative properties. Preclinical in vitro and in vivo data have shown curcumin to be an effective treatment for multiple cancers. These effects are drived by curcumin's ability to induce G2/M cell cycle arrest, induction of autophagy, activation of apoptotic pathways, disruption of molecular signaling, inhibition of invasion and metastasis, and by increasing the efficacy of existing chemotherapeutics. Here we focused on the hormetic behaviour of curcumin. Frequently, low doses of toxins and other stressors not only are harmless but also activate an adaptive stress whereas high dose activates acute responses like autophagy and cell death. This phenomenon is referred to as hormesis. Many molecules that cause cell death elicite an initial autophagic step that is a cytoprotective mechanism relying on elimination of dysfunctional structures intracellular, notably by mitophagy. This phenomenon is considered as a primarily protective mechanism against stressors. At higher doses, cells undergo mitochondrial outer membrane permeabilization due to calcium release from the endoplasmic reticulum and die. Herein, we address the complex crosstalk between the induced mitochondrial biogenesis, mitochondrial destabilization accompanied by mitophagy and cell death that can also be at play.

scholarly journals Fasudil Attenuates Adriamycin-Induced Cardiac Damage by Modifying Oxidative Stress and Apoptosis Mediated Cellular Signaling

2021 ◽  
Author(s):  
Yi Yan ◽  
Chengyu Xiang ◽  
Dingguo Zhang
Keyword(s):  
Mouse Model ◽  
Kinase Inhibitor ◽  
Rho Kinase ◽  
Control Group ◽  
H9c2 Cell ◽  
Protective Mechanism ◽  
High Dose ◽  
Cardiac Damage

Abstract PURPOSETo explore the protective mechanism of fasudil,a Rho kinase inhibitor, on acute cardiac injury induced by adriamycin(ADR).METHODSIn vitro investigations on H9C2 cell line, as well as an in vivo study in a mouse model of ADR-induced acute cardiomyopathy, were performed. In vitro, H9C2 cells were treated with fasudil for 30mins then incubated with ADR for 24 hours. Cells were collected for immunohistochemistry and western blot study, respectively. In vivo, C57BL6 mice were randomly divided into the following four groups: ①ADR group;②low-dose fasudil ( ADR+L);③high-dose fasudil ( ADR+H); and ④control group(CON). Animals were injected i.p 20 mg/kg ADR once in group①~③. And animals were injected i.p fasudil (2 or 10 mg/kg/day ) daily once for six times in group ②and ③,respectively. Blood samples and heart tissues were collected for assays.RESULTSIn vitro, fasudil treatment ameliorated ADR-induced immunofluorescence reaction of 8-OHdG, decreased the expression of TUNEL cells and protein of Bax、Caspase-3 and p53,and increased the expression of protein of Bcl-2 and SIRT 1. In the mouse model, administration of fasudil significantly ameliorated ADR-induced cardiac damage, suppressed cell apoptosis and senescence, ameliorated redox imbalance and DNA damage.CONCLUSIONFasudil has the protective effect on adriamycin induced acute cardiotoxicity, which partially attributed to its antioxidant, anti-senescence, and anti-apoptotic effects of inhibiting the RhoA/Rho kinase signaling pathway.

Bicarbonate transport along the loop of Henle effects of adrenal steroids

1995 ◽  
Vol 268 (2) ◽  
pp. F234-F239 ◽  
Author(s):  
R. Unwin ◽  
G. Capasso ◽  
G. Giebisch
Keyword(s):  
Low Dose ◽  
Bicarbonate Transport ◽  
High Dose ◽  
Loop Of Henle ◽  
Adrenal Steroids ◽  
Fluid Reabsorption ◽  
Physiological Dose

The role of adrenal steroids in the regulation of bicarbonate absorption in the loop of Henle was studied by in vivo microperfusion. Bicarbonate transport (JHCO3) was measured by microcalorimetry and fluid reabsorption by [14C]inulin, 7-10 days after surgery, in 1) sham-operated control rats, 2) adrenalectomized (Adx) rats, 3) Adx rats receiving dexamethasone (1.2 micrograms.100 g body wt-1.24 h-1) and a low dose of aldosterone (0.5 micrograms.100 g body wt-1.24 h-1), 4) Adx rats receiving dexamethasone, 5) Adx rats receiving a low dose of aldosterone, and 6) Adx rats receiving a high dose of aldosterone (1.0 micrograms.100 g body wt-1.24 h-1). JHCO3 along the loop of Henle was decreased by 40% in Adx rats. JHCO3 was increased by dexamethasone alone and by dexamethasone plus a low dose of aldosterone to rates observed in fully supplemented Adx rats. Aldosterone given alone at a low physiological dose had no effect, but, when administered at a high dose, returned JHCO3 to normal.

scholarly journals Anti- Toxoplasma gondii effect of Lumefantrine in vitro and in vivo

2020 ◽  
Author(s):  
Dawei Wang ◽  
Mengen Xing ◽  
Saeed El-Ashram ◽  
Yingying Ding ◽  
Xiaoyu Sang ◽  
...  
Keyword(s):  
Side Effects ◽  
Toxoplasma Gondii ◽  
Mtt Assay ◽  
Vero Cells ◽  
Protective Mechanism ◽  
High Dose ◽  
Mouse Tissues ◽  
Ifn Γ

Abstract Background: Toxoplasma gondii is an obligate intracellular protozoan parasite, which can infect almost all warm-blooded animals, including humans, leading to toxoplasmosis. Currently, the effective treatment for human toxoplasmosis is the combination of sulfadiazine and pyrimethamine. However, both drugs have serious side effects and toxicity in the host. Therefore, there is an urgent need for the discovery of new anti-Toxoplasma drugs with high potency and less or no side-effects. Methods: The cytotoxicity of sulfadiazine and lumefantrine to Vero cells was evaluated by the methyl thiazolyl tetrazolium (MTT) assay. And MTT assay was also used to detect the inhibitory effects of lumefantrine on parasites invasion and proliferation. Flow cytometry was conducted to further verify parasites proliferation. qPCR was performed to evaluate the parasite load in the mice after lumefantrine treatment. In order to determine whether lumefantrine treatment enhances Th1 or Th2 cytokine response, IFN-γ, IL-4, and IL-10 levels in the serum of mice were determined. Results: Our findings suggest that lumefantrine exerts activity against T. gondii by inhibiting its replication and invasion of Vero cells in vitro without being toxic to the cells. Furthermore, lumefantrine protected mice with acute toxoplasmosis from death to a certain extent and reduced the parasite burden in mouse tissues in vivo. In addition, a significant increase in IFN-γ production was observed in high dose lumefantrine-treated mice while IL-10 and IL-4 levels increased in low dose lumefantrine-treated mice. Conclusions: The results of this study demonstrated that lumefantrine may be a promising agent to treat toxoplamosis, and more experiments on the protective mechanism of lumefantrine should be undertaken in further studies.Key words: Toxoplasma gondii, Lumefantrine, anti-Toxoplasma gondii, Invasion, Proliferation

The Role of Polyphenols in the Modulation of Plasma Non-Enzymatic Antioxidant Capacity (NEAC)

2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito
Keyword(s):  
Antioxidant Capacity ◽  
Dietary Intervention ◽  
Ex Vivo ◽  
The Body ◽  
Dietary Polyphenols ◽  
Enzymatic Antioxidant ◽  
Endogenous Antioxidant

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.

Significance of Platelet β-Adrenoceptors for Platelet Responses In Vivo and In Vitro

1992 ◽  
Vol 68 (06) ◽  
pp. 687-693 ◽  
Author(s):  
P T Larsson ◽  
N H Wallén ◽  
A Martinsson ◽  
N Egberg ◽  
P Hjemdahl
Keyword(s):  
Ex Vivo ◽  
High Dose ◽  
Platelet Aggregability ◽  
Adrenoceptor Agonist ◽  
Dose Infusion ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Factor Antigen

SummaryThe significance of platelet β-adrenoceptors for platelet responses to adrenergic stimuli in vivo and in vitro was studied in healthy volunteers. Low dose infusion of the β-adrenoceptor agonist isoprenaline decreased platelet aggregability in vivo as measured by ex vivo filtragometry. Infusion of adrenaline, a mixed α- and β-adrenoceptor agonist, increased platelet aggregability in vivo markedly, as measured by ex vivo filtragometry and plasma β-thromboglobulin levels. Adrenaline levels were 3–4 nM in venous plasma during infusion. Both adrenaline and high dose isoprenaline elevated plasma von Willebrand factor antigen levels β-Blockade by propranolol did not alter our measures of platelet aggregability at rest or during adrenaline infusions, but inhibited adrenaline-induced increases in vWf:ag. In a model using filtragometry to assess platelet aggregability in whole blood in vitro, propranolol enhanced the proaggregatory actions of 5 nM, but not of 10 nM adrenaline. The present data suggest that β-adrenoceptor stimulation can inhibit platelet function in vivo but that effects of adrenaline at high physiological concentrations are dominated by an α-adrenoceptor mediated proaggregatory action.

FEMALE ENDOCRINE CONTROL MECHANISMS DURING THE NEONATAL PERIOD

1972 ◽  
Vol 70 (2) ◽  
pp. 396-408 ◽  
Author(s):  
K.-D. Schulz ◽  
H. Haarmann ◽  
A. Harland
Keyword(s):  
Protein Synthesis ◽  
Reproductive System ◽  
Rna Synthesis ◽  
Neonatal Period ◽  
High Dose ◽  
Female Reproductive System ◽  
Endocrine Control ◽  
Hypothalamic Region ◽  
Rna And Protein Synthesis ◽  
Physiological Dose

ABSTRACT The present investigation deals with the oestrogen-sensitivity of the female reproductive system during the neonatal period. Newborn female guinea pigs were used as test animals. At different times after a single subcutaneous injection of a physiological dose of 0.1 μg or an unphysiologically high dose of 10 μg 17β-oestradiol/100 g body weight, the RNA- and protein-synthesis was examined in the hypothalamic region, pituitary, cerebral cortex, liver, adrenal gland, ovary and uterus. With a physiological dose an increase in organ weight, protein content, RNA-and protein-synthesis was found only in the uterus. These alterations turned out to be dose-dependent. In addition to the findings in the uterus an inhibition of the aminoacid incorporation rate occurred in the liver following the injection of the high oestradiol dose. As early as 1 hour after the administration of 0.1 μg 17β-oestradiol an almost 100% increase in uterine protein synthesis was detectable. This result demonstrates a high oestrogen-sensitivity of this organ during the neonatal period. All the other organs of the female reproductive system such as the hypothalamus, pituitary and ovary did not show any oestrogen response. Therefore the functional immaturity of the uterus during post partem life is not the result of a deficient hormone sensitivity but is correlated with the absence of a sufficient hormonal stimulus at this time. The investigation on the effects of actinomycin resulted in different reactions in the uterus and liver. In contrast to the liver a paradoxical actinomycin effect was found in the uterus after treatment with actinomycin alone. This effect is characterized by a small inhibition of RNA-synthesis and a 50% increase in protein synthesis. The treatment of the newborn test animals with actinomycin and 17β-oestradiol together abolished the oestrogen-induced stimulation of the uterine RNA-and protein-synthesis. Consequently, the effect of oestrogens during the neonatal period is also connected with the formation of new proteins via an increased DNA-directed RNA-synthesis.

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