Metabolic control of resistance of human epithelial cells to H2O2 and NO stresses

The carbon flux through the oxidative branch of the pentose phosphate pathway (PPP) can be viewed as an integrator of the antioxidant mechanisms via the generation of NADPH. It could therefore be used as a control point of the cellular response to an oxidative stress. Replacement of glucose by galactose sensitized the human epithelial cell line HGT-1 to H2O2 stress. Here we demonstrate that, due to the restricted galactose flux into the PPP, the H2O2 stress led to early cellular blebbing followed by cell necrosis, these changes being associated with a fall in the NADPH/NADP+ ratio and GSH depletion. H2O2 cytotoxicity was prevented by adding 2-deoxyglucose (2dGlc). This protection was associated with an increased flow of 2-deoxyglucose 6-phosphate into the oxidative branch of the PPP together with the prevention of the NADPH/NADP+ fall and the maintenance of intracellular GSH redox homoeostasis. Inhibitors of enzyme pathways connecting the PPP to GSH recycling abolished the 2dGlc protection. In carbohydrate-free culture conditions, 2dGlc dose-dependent protective effect was paralleled by a dose-dependent influx of 2dGlc into the PPP leading to the maintenance of the intracellular redox status. By contrast, in Glc-fed cells, the PPP was not a control point of the cellular resistance to H2O2 stress as they maintained a high NADPH/NADP+ ratio. Both 2dGlc and Glc inhibited, through the maintenance of GSH redox status, NO cytotoxicity on galactose-containing Dulbecco's modified Eagle's medium (Gal-DMEM)-fed cells. 2dGlc did not prevent the fall of ATP content in NO-treated Gal-DMEM-fed cells, indicating that NO cytotoxicity was essentially due to the disruption of GSH redox homoeostasis and not to the alteration of ATP production by the mitochondrial respiratory chain. The maintenance of ATP content in NO-treated glucose-fed cells was due to their ability to derive their energy from anaerobic glycolysis. In conclusion, Gal-DMEM and 2dGlc-supplemented Gal-DMEM provide a useful system to decipher and organize into a hierarchy the targets of several stresses at the level of intact barrier epithelial cells.

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Targeted Antimicrobial Photochemotherapy

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.10.2595 ◽

1998 ◽

Vol 42 (10) ◽

pp. 2595-2601 ◽

Cited By ~ 157

Author(s):

Nikolaos S. Soukos ◽

Laurie Ann Ximenez-Fyvie ◽

Michael R. Hamblin ◽

Sigmund S. Socransky ◽

Tayyaba Hasan

Keyword(s):

Epithelial Cells ◽

Mammalian Cells ◽

Negative Charge ◽

Positive Charge ◽

Average Molecular Weight ◽

Red Light ◽

Epithelial Cell Line ◽

New Approach ◽

Oral Epithelial ◽

Dose Dependent

ABSTRACT This study explores a new approach for antimicrobial therapy with light activation of targeted poly-l-lysine (pL)–chlorine6 (c e6 ) conjugates. The goal was to test the hypothesis that these conjugates between pL and c e6 would efficiently target photodestruction towards gram-positive (Actinomyces viscosus) and gram-negative (Porphyromonas gingivalis) oral species while sparing an oral epithelial cell line (HCPC-1). Conjugates of c e6 with pL (average molecular weight, 2,000) having a positive, neutral, or negative charge were prepared. Illumination with red light (λmax = 671 nm) from a diode array produced a dose-dependent loss of CFU from the bacteria, under conditions that did not affect the viability of the epithelial cells. For P. gingivalis, the cationic conjugate produced 99% killing, while the neutral conjugate killed 91% and the anionic conjugate killed 76% after 1 min of incubation and exposure to red light for 10 min. For A. viscosus, the cationic conjugate produced >99.99% killing while HCPC-1 cells remained intact. The importance of the positive charge was shown by the effectiveness of c e6 -monoethylenediamine monoamide (a monocationic derivative of c e6 ) in killing both bacteria. The clinically employed benzoporphyrin derivative under the same conditions killed epithelial cells while leaving P. gingivalis relatively unharmed. A mixture of c e6 with pL did not show phototoxicity comparable with that of the cationic conjugate. These results were explained by the selective uptake of the conjugates by bacteria (20- to 100-fold) compared to that by mammalian cells, while free c e6 showed much less selectivity for bacteria (5- to 20-fold). The data suggest that the cationic pL-c e6 conjugate may have an application for the photodynamic therapy of periodontal disease.

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Neurons undergo pathogenic metabolic reprograming in models of familial ALS

10.1101/2021.08.20.457111 ◽

2021 ◽

Author(s):

Sean-Patrick Riechers ◽

Jelena Mojsilovic-Petrovic ◽

Mehraveh Garjani ◽

Valentina Medvedeva ◽

Casey Dalton ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Redox Status ◽

Pentose Phosphate ◽

Glycolytic Flux ◽

Loss Of Function ◽

Atp Production ◽

Familial Als ◽

Normal Cellular Function ◽

Production Demand ◽

Lateral Sclerosis

SummaryNormal cellular function requires a rate of ATP production sufficient to meet demand. In most neurodegenerative diseases (including Amyotrophic Lateral Sclerosis, ALS), mitochondrial dysfunction is postulated raising the possibility of impaired ATP production and a need for compensatory maneuvers to sustain the ATP production/demand balance. We find in our rodent models of familial ALS (fALS), impairment in neuronal glycolytic flux with maintained or enhanced activity of the citric acid cycle. This rewiring of metabolism is associated with normal ATP levels and redox status, supporting the notion that mitochondrial function is not compromised in neurons expressing fALS genes. Genetic loss-of-function manipulation of individual steps in the glycolysis and the pentose phosphate pathway blunt the negative phenotypes seen in various fALS models. We propose that neurons adjust fuel utilization in the setting of neurodegenerative disease-associated mitochondrial dysfunction in a baleful manner and targeting this process can be healthful.

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Antioxidant Supplementation and Adaptive Response to Training: A Systematic Review

Current Pharmaceutical Design ◽

10.2174/1381612825666190701164923 ◽

2019 ◽

Vol 25 (16) ◽

pp. 1889-1912 ◽

Cited By ~ 8

Author(s):

Rosario Pastor ◽

Josep A. Tur

Keyword(s):

Antioxidant Enzymes ◽

Cellular Response ◽

Recovery Period ◽

Chronic Administration ◽

Antioxidant Response ◽

Redox Status ◽

Exercise Session ◽

Acute Administration ◽

Antioxidant Supplementation ◽

Antioxidant Supplements

Background: Antioxidant supplementation has become a common practice among athletes to theoretically achieve a reduction in oxidative stress, promote recovery and improve performance. Objective: To assess the effect of antioxidant supplements on exercise. Methods: A systematic literature search was performed up to January 2019 in MEDLINE via EBSCO and Pubmed, and in Web of Sciences based on the following terms: “antioxidants” [Major] AND “exercise” AND “adaptation”; “antioxidant supplement” AND “(exercise or physical activity)” AND “(adaptation or adjustment)” [MesH]. Thirty-six articles were finally included. Results: Exhaustive exercise induces an antioxidant response in neutrophils through an increase in antioxidant enzymes, and antioxidant low-level supplementation does not block this adaptive cellular response. Supplementation with antioxidants appears to decrease oxidative damage blocking cell-signaling pathways associated with muscle hypertrophy. However, upregulation of endogenous antioxidant enzymes after resistance training is blocked by exogenous antioxidant supplementation. Supplementation with antioxidants does not affect the performance improvement induced by resistance exercise. The effects of antioxidant supplementation on physical performance and redox status may vary depending on baseline levels. Conclusion: The antioxidant response to exercise has two components: At the time of stress and adaptation through genetic modulation processes in front of persistent pro-oxidant situation. Acute administration of antioxidants immediately before or during an exercise session can have beneficial effects, such as a delay in the onset of fatigue and a reduction in the recovery period. Chronic administration of antioxidant supplements may impair exercise adaptations, and is only beneficial in subjects with low basal levels of antioxidants.

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Cinnamon Oil Inhibits Penicillium expansum Growth by Disturbing the Carbohydrate Metabolic Process

Journal of Fungi ◽

10.3390/jof7020123 ◽

2021 ◽

Vol 7 (2) ◽

pp. 123

Author(s):

Tongfei Lai ◽

Yangying Sun ◽

Yaoyao Liu ◽

Ran Li ◽

Yuanzhi Chen ◽

...

Keyword(s):

Pentose Phosphate ◽

Metabolic Process ◽

Penicillium Expansum ◽

Economic Losses ◽

Pome Fruit ◽

Cinnamon Oil ◽

Atp Production ◽

Protein Levels ◽

Regulatory Enzymes ◽

Expression Of Genes

Penicillium expansum is a major postharvest pathogen that mainly threatens the global pome fruit industry and causes great economic losses annually. In the present study, the antifungal effects and potential mechanism of cinnamon oil against P. expansum were investigated. Results indicated that 0.25 mg L−1 cinnamon oil could efficiently inhibit the spore germination, conidial production, mycelial accumulation, and expansion of P. expansum. In addition, it could effectively control blue mold rots induced by P. expansum in apples. Cinnamon oil could also reduce the expression of genes involved in patulin biosynthesis. Through a proteomic quantitative analysis, a total of 146 differentially expressed proteins (DEPs) involved in the carbohydrate metabolic process, most of which were down-regulated, were noticed for their large number and functional significance. Meanwhile, the expressions of 14 candidate genes corresponding to DEPs and the activities of six key regulatory enzymes (involving in cellulose hydrolyzation, Krebs circle, glycolysis, and pentose phosphate pathway) showed a similar trend in protein levels. In addition, extracellular carbohydrate consumption, intracellular carbohydrate accumulation, and ATP production of P. expansum under cinnamon oil stress were significantly decreased. Basing on the correlated and mutually authenticated results, we speculated that disturbing the fungal carbohydrate metabolic process would be partly responsible for the inhibitory effects of cinnamon oil on P. expansum growth. The findings would provide new insights into the antimicrobial mode of cinnamon oil.

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Three-dimensional Growth of Renal Epithelial Cells in Vitro: A Tool in Toxicity Testing

Alternatives to Laboratory Animals ◽

10.1177/026119299302100212 ◽

1993 ◽

Vol 21 (2) ◽

pp. 191-195 ◽

Cited By ~ 1

Author(s):

Knut-Jan Andersen ◽

Erik Ilsø Christensen ◽

Hogne Vik

Keyword(s):

Epithelial Cells ◽

Three Dimensional ◽

Toxicity Testing ◽

Renal Tissue ◽

Epithelial Cell Line ◽

Multicellular Spheroids ◽

Renal Epithelial Cell ◽

Renal Epithelial Cells

The tissue culture of multicellular spheroids from the renal epithelial cell line LLC-PK1 (proximal tubule) is described. This represents a biological system of intermediate complexity between renal tissue in vivo and simple monolayer cultures. The multicellular structures, which show many similarities to kidney tubules in vivo, including a vectorial water transport, should prove useful for studying the potential nephrotoxicity of drugs and chemicals in vitro. In addition, the propagation of renal epithelial cells as multicellular spheroids in serum-free culture may provide information on the release of specific biological parameters, which may be suppressed or masked in serum-supplemented media.

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Stimulation of both human bronchial epithelium and neutrophils is needed for maximal interactive adhesion

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1996.270.1.l80 ◽

1996 ◽

Vol 270 (1) ◽

pp. L80-L87 ◽

Cited By ~ 5

Author(s):

P. G. Bloemen ◽

M. C. Van den Tweel ◽

P. A. Henricks ◽

F. Engels ◽

M. J. Van de Velde ◽

...

Keyword(s):

Epithelial Cells ◽

Cultured Cells ◽

Bronchial Epithelium ◽

Bronchial Epithelial Cells ◽

Intercellular Adhesion Molecule ◽

Tnf Alpha ◽

Epithelial Cell Line ◽

Ifn Gamma ◽

Bronchial Epithelial ◽

Stimulation Of

It has become clear that the bronchial epithelium is not just a passive barrier but plays an active role in inflammation. It can produce several inflammatory mediators and does express cell adhesion molecules of which intercellular adhesion molecule (ICAM)-1 can be upregulated by cytokines like interferon (IFN)-gamma. In the present study, we analyzed in detail the interaction of neutrophils with human bronchial epithelial cells, both primary cultured cells and the bronchial epithelial cell line BEAS-2B. Confluent monolayers of epithelial cells were incubated with freshly isolated 51Cr-labeled neutrophils for 30 min at 37 degrees C; then the nonadherent cells were removed by washing gently. Stimulation of the epithelial cells with IFN-gamma or the combination of IFN-gamma and tumor necrosis factor-alpha (TNF-alpha) (which doubles the ICAM-1 expression) increased neutrophil adhesion. Activation of the neutrophils themselves with N-formylmethionyl-leucyl-phenylalanine (fMLP), platelet-activating factor, or TNF-alpha also caused a profound enhancement of the adhesion. A significant additional increase was found when the epithelial cells had been exposed to IFN-gamma and the neutrophils were stimulated with fMLP simultaneously. This effect was even more pronounced with epithelium preincubated with IFN-gamma and TNF-alpha. With the use of monoclonal antibodies against CD18 and ICAM-1, it was demonstrated that the increased adhesion was mainly mediated by the ICAM-1/beta 2-integrin interaction. This study highlights that both the activation state of the bronchial epithelial cells and the activation state of the neutrophils are critical for their interactive adhesion.

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The Role of the Pathogen Dose and PI3Kγ in Immunometabolic Reprogramming of Microglia for Innate Immune Memory

International Journal of Molecular Sciences ◽

10.3390/ijms22052578 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2578

Author(s):

Trim Lajqi ◽

Christian Marx ◽

Hannes Hudalla ◽

Fabienne Haas ◽

Silke Große ◽

...

Keyword(s):

Oxygen Consumption ◽

Immune Tolerance ◽

Immune Cells ◽

Low Dose ◽

Innate Immune ◽

Immune Memory ◽

Innate Immune Cells ◽

Atp Production ◽

Dose Dependent

Microglia, the innate immune cells of the CNS, exhibit long-term response changes indicative of innate immune memory (IIM). Our previous studies revealed IIM patterns of microglia with opposing immune phenotypes: trained immunity after a low dose and immune tolerance after a high dose challenge with pathogen-associated molecular patterns (PAMP). Compelling evidence shows that innate immune cells adopt features of IIM via immunometabolic control. However, immunometabolic reprogramming involved in the regulation of IIM in microglia has not been fully addressed. Here, we evaluated the impact of dose-dependent microglial priming with ultra-low (ULP, 1 fg/mL) and high (HP, 100 ng/mL) lipopolysaccharide (LPS) doses on immunometabolic rewiring. Furthermore, we addressed the role of PI3Kγ on immunometabolic control using naïve primary microglia derived from newborn wild-type mice, PI3Kγ-deficient mice and mice carrying a targeted mutation causing loss of lipid kinase activity. We found that ULP-induced IIM triggered an enhancement of oxygen consumption and ATP production. In contrast, HP was followed by suppressed oxygen consumption and glycolytic activity indicative of immune tolerance. PI3Kγ inhibited glycolysis due to modulation of cAMP-dependent pathways. However, no impact of specific PI3Kγ signaling on immunometabolic rewiring due to dose-dependent LPS priming was detected. In conclusion, immunometabolic reprogramming of microglia is involved in IIM in a dose-dependent manner via the glycolytic pathway, oxygen consumption and ATP production: ULP (ultra-low-dose priming) increases it, while HP reduces it.

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Protective effects of astaxanthin on lipopolysaccharide-induced inflammation in bovine endometrial epithelial cells†

Biology of Reproduction ◽

10.1093/biolre/ioz187 ◽

2019 ◽

Vol 102 (2) ◽

pp. 339-347 ◽

Cited By ~ 4

Author(s):

Fa-Chun Wan ◽

Chen Zhang ◽

Qing Jin ◽

Chen Wei ◽

Hong-Bo Zhao ◽

...

Keyword(s):

Growth Factor ◽

Epithelial Cells ◽

B Cell Lymphoma ◽

Resistant Bacteria ◽

Epithelial Cell Line ◽

Protective Effects ◽

Necrosis Factor Alpha ◽

Antibiotic Resistant ◽

Injury Treatment ◽

Endometrial Epithelial Cells

Abstract Astaxanthin (AST), a natural antioxidant carotenoid, has been shown to exert anti-inflammatory effects. However, to our knowledge, no study has specifically addressed the potential protective effects of AST against bovine endometritis. The purpose of this study was to examine whether treatment with AST could protect endometrial epithelial cells against lipopolysaccharide (LPS)-induced inflammatory injury. Treatment of bovine endometrial (BEND) epithelial cell line with AST reduced LPS-induced production of interleukin-6 and tumor necrosis factor-alpha, increased the cellular activity of superoxide dismutase and catalase, decreased the proportion of apoptotic cells, and promoted the production of insulin-like growth factor and epithelial growth factor. The effects of AST were mediated through the downregulation of B-cell lymphoma 2 (Bcl-2) associated X, apoptosis regulator (Bax), and cleaved caspase-3 and through the upregulation of Bcl-2. Moreover, AST significantly increased the expression of the tight junction proteins (TJP) claudin, cadherin-1, and TJP1, which play an essential role in the maintenance of host endometrial defense barrier against pathogen infection. Collectively, these results demonstrated that treatment with AST protected against oxidative stress, prevented cell apoptosis, promoted BEND cells viability, and increased the production of growth factors, in addition to activating the endometrial defense barrier. Therefore, AST is a promising therapeutic agent for the prevention and treatment of endometritis. This finding is of utmost importance in the present times when the excessive use of antibiotics has resulted in the development of antibiotic-resistant bacteria.

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The Role of Herbal Bioactive Components in Mitochondria Function and Cancer Therapy

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2019/3868354 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Fangfang Tao ◽

Yanrong Zhang ◽

Zhiqian Zhang

Keyword(s):

Cancer Therapy ◽

Cancer Cell ◽

Apoptotic Cell ◽

Redox Status ◽

Cancer Therapies ◽

Bioactive Components ◽

Atp Production

Mitochondria are highly dynamic double-membrane organelles which play a well-recognized role in ATP production, calcium homeostasis, oxidation-reduction (redox) status, apoptotic cell death, and inflammation. Dysfunction of mitochondria has long been observed in a number of human diseases, including cancer. Targeting mitochondria metabolism in tumors as a cancer therapeutic strategy has attracted much attention for researchers in recent years due to the essential role of mitochondria in cancer cell growth, apoptosis, and progression. On the other hand, a series of studies have indicated that traditional medicinal herbs, including traditional Chinese medicines (TCM), exert their potential anticancer effects as an effective adjunct treatment for alleviating the systemic side effects of conventional cancer therapies, for reducing the risk of recurrence and cancer mortality and for improving the quality of patients’ life. An amazing feature of these structurally diverse bioactive components is that majority of them target mitochondria to provoke cancer cell-specific death program. The aim of this review is to summarize the in vitro and in vivo studies about the role of these herbs, especially their bioactive compounds in the modulation of the disturbed mitochondrial function for cancer therapy.

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