scholarly journals Dynamic polyphosphate metabolism coordinating with manganese ions defends against oxidative stress in the extreme bacterium Deinococcus radiodurans

2021 ◽  
Author(s):  
Shang Dai ◽  
Zhenming Xie ◽  
Binqiang Wang ◽  
Ning Yu ◽  
Jie Zhao ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Deinococcus Radiodurans ◽  
Expression Profiles ◽  
Resistance Mechanism ◽  
Homeostatic Regulation ◽  
Defense Strategy ◽  
Oxidative Stresses ◽  
Pi Complex ◽  
Pi Complexes ◽  
Polyphosphate Metabolism

Deinococcus radiodurans is an extreme bacterium with unparalleled resistance to oxidative stresses. Accumulation of intracellular Mn2+ complexing with small metabolites is the key contributor to the tolerance of D. radiodurans against oxidative stress. However, the intracellular reservoir of Mn ions and homeostatic regulation of the Mn-complex in D. radiodurans remain unclear. We identified an evolutionarily ancient and negatively charged phosphate polymer (polyphosphate, PolyP) in D. radiodurans. We investigated the PolyP metabolism in the response of D. radiodurans to oxidative stress. The genes dr1939, encoding polyphosphatase kinase (PPKDr), and dra0185, encoding exopolyphosphatase (PPXDr), were identified. PPXDr is a novel exopolyphosphatase with a cofactor preference to Mn2+, which enhances the dimerization and activity of PPXDr to allow the effective cleavage of PolyP-Mn. PPKDr and PPXDr exhibited different dynamic expression profiles under oxidative stress. First, the ppkDr was upregulated leading to the accumulation of PolyP, which chelated large amounts of intracellular Mn ions. Subsequently, the expression level of ppkDr decreased while the ppxDr was substantially upregulated and effectively hydrolyzed inactive PolyP-Mn to release phosphate (Pi) and Mn2+, which could form into Mn-Pi complexes to scavenge O2- and protect proteins from oxidative damage. Hence, dynamic cellular PolyP metabolites complexed with free Mn ions highlight a defense strategy of D. radiodurans in response to oxidative stress. Importance Mn-phosphate complex (Mn-Pi) plays a key role in the cellular resistance of radioresistant bacteria. The evolutionarily ancient polyphosphate polymers (PolyP) could effectively chelate Mn2+ and donate phosphates. However, the intracellular reservoir of Mn ions and homeostatic regulation of the Mn-Pi complex remain unclear. Here, we investigated the relationship of PolyP metabolites and Mn2+ homeostasis, and how they function to defend against oxidative stress in the radioresistant bacterium Deinococcus radiodurans. We found that PPXDr is a novel exopolyphosphatase with a cofactor preference for Mn2+, mediating PolyP-Mn degradation into Pi and Mn ions. The formed Mn-Pi complexes effectively protect proteins. The dynamic PolyP metabolism coordinating with Mn ions is a defense strategy of D. radiodurans in response to oxidative stress. The findings not only provide new insights into the resistance mechanism of the extreme bacterium D. radiodurans but also broaden our understanding of the functions of PolyP metabolism in organisms.

Alpha-1-Antichymotrypsin: a Common Player for Type 2 Diabetes and Alzheimer's Disease

2020 ◽  
Vol 16 ◽  
Author(s):  
Nataly Guzmán-Herrera ◽  
Viridiana C. Pérez-Nájera ◽  
Luis A. Salazar-Olivo
Keyword(s):  
Oxidative Stress ◽  
Alzheimer’S Disease ◽  
Type 2 Diabetes ◽  
Alzheimer's Disease ◽  
Regulatory Networks ◽  
Therapeutic Strategies ◽  
Oxidative Stresses ◽  
Bibliographic Search ◽  
And Oxidative Stress

Background: Numerous studies have shown a significant association between type 2 diabetes mellitus (T2D) and Alzheimer's disease (AD), two pathologies affecting millions of people worldwide. Chronic inflammation and oxidative stress are two conditions common to these diseases also affecting the activity of the serpin alpha-1-antichymotrypsin (ACT), but a possible common role for this serpin in T2D and AD remains unclear. Objective: To explore the possible regulatory networks linking ACT to T2D and AD. Materials and Methods: A bibliographic search was carried out in PubMed, Med-line, Open-i, ScienceDirect, Scopus and SpringerLink for data indicating or suggesting association among T2D, AD, and ACT. Searched terms like “alpha-1-antichymotrypsin”, “type 2 diabetes”, “Alzheimer's disease”, “oxidative stress”, “pro-inflammatory mediators” among others were used. Moreover, common therapeutic strategies between T2D and AD as well as the use of ACT as a therapeutic target for both diseases were included. Results: ACT has been linked with development and maintenance of T2D and AD and studies suggest their participation through activation of inflammatory pathways and oxidative stress, mechanisms also associated with both diseases. Likewise, evidences indicate that diverse therapeutic approaches are common to both diseases. Conclusion: Inflammatory and oxidative stresses constitute a crossroad for T2D and AD where ACT could play an important role. In-depth research on ACT involvement in these two dysfunctions could generate new therapeutic strategies for T2D and AD.

scholarly journals Recurrent Indoor Environmental Pollution and Its Impact on Health and Oxidative Stress of the Textile Workers in Bangladesh

2020 ◽  
Vol 14 ◽  
pp. 117863022093839
Author(s):  
Tania Rahman ◽  
Ar-Rafi Md. Faisal ◽  
Tahura Khanam ◽  
Hossain Uddin Shekhar
Keyword(s):  
Oxidative Stress ◽  
Ascorbic Acid ◽  
Occupational Health ◽  
Environmental Pollution ◽  
Control Area ◽  
Textile Workers ◽  
Control Subjects ◽  
Oxidative Stresses ◽  
Healthy Control ◽  
Textile Industries

Perennial indoor environmental pollution in the textile industrial area is a potential health hazard for workers engaged in this line of work, resulting in mental aberration to severe health risks. This study was designed to investigate the indoor environmental quality of textile industries and correlate its effect on the occupational health and well-being of the textile workers by measuring plasma oxidative stress status in textile workers and healthy control subjects. Environmental samples were collected from 15 textile industries located in Dhaka division, and 30 volunteer textile workers and 30 volunteer office workers (control) aged 18 to 57 years participated in the study. The concentration of plasma ascorbic acid (P-ASC), plasma malondialdehyde (P-MDA), and plasma conjugated diene (P-CD) was measured in both groups. The noise level (78.0 ± 0.68 dB) and the formaldehyde level (141.80 ± 4.47 µg/m3) were found to be significantly higher in the indoor environmental area compared with those in the control area (70.17 ± 0.25 dB and 108.0 ± 0.76 µg/m3, respectively). Furthermore, the daily average concentration of suspended particulate matters (PMs), that is, PM2.5 (322.2 ± 13.46 µg/m3) and PM10 (411.0 ± 17.57 µg/m3), was also found to be significantly higher in the indoor environmental air compared with that in the control area (78.59 ± 1.66 and 174.0 ± 2.33 µg/m3, respectively). The levels of P-MDA (0.37 ± 0.03 nmol/L) and P-CD (14.74 ± 0.61 nmol/L) were significantly increased, whereas the level of P-ASC level (0.46 ± 0.04 mg/dL) was markedly decreased in the textile workers compared with the healthy control subjects (0.18 ± 0.01 nmol/L of P-MDA, 10.04 ± 0.44 nmol/L of P-CD, and 1.29 ± 0.06 mg/dL of P-ASC). The textile plants were found to have significantly elevated levels of indoor environmental pollutants compared with those in the control area, and the textile workers were significantly exposed to oxidative stresses compared with the control subjects. The use of noise pads and high-efficiency air filters is perhaps highly instrumental to put an end to this prevailing situation. Moreover, to overcome the oxidative stresses among workers, supplementation of antioxidant vitamins (ie, ascorbic acid and/or vitamin E) may be beneficial. In addition, to prevent serious health-related issues, proper precautions should be taken to protect the occupational health of the textile workers.

scholarly journals Transcriptome Analysis of Eggplant Root in Response to Root-Knot Nematode Infection

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 470
Author(s):  
Min Zhang ◽  
Hongyuan Zhang ◽  
Jie Tan ◽  
Shuping Huang ◽  
Xia Chen ◽  
...  
Keyword(s):  
Defense Mechanisms ◽  
Expression Profiles ◽  
Resistance Mechanism ◽  
Solanum Melongena ◽  
Enrichment Analysis ◽  
Nematode Resistance ◽  
Differentially Expressed ◽  
Root Knot Nematode ◽  
Solanum Torvum ◽  
Plant Nematode

Eggplant (Solanum melongena L.), which belongs to the Solanaceae family, is an important vegetable crop. However, its production is severely threatened by root-knot nematodes (RKNs) in many countries. Solanum torvum, a wild relative of eggplant, is employed worldwide as rootstock for eggplant cultivation due to its resistance to soil-borne diseases such as RKNs. In this study, to identify the RKN defense mechanisms, the transcriptomic profiles of eggplant and Solanum torvum were compared. A total of 5360 differentially expressed genes (DEGs) were identified for the response to RKN infection. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that these DEGs are mainly involved in the processes of response to stimulus, protein phosphorylation, hormone signal transduction, and plant-pathogen interaction pathways. Many phytohormone-related genes and transcription factors (MYB, WRKY, and NAC) were differentially expressed at the four time points (ck, 7, 14, and 28 days post-infection). The abscisic acid signaling pathway might be involved in plant-nematode interactions. qRT-PCR validated the expression levels of some of the DEGs in eggplant. These findings demonstrate the nematode-induced expression profiles and provide some insights into the nematode resistance mechanism in eggplant.

scholarly journals Keap1 deletion accelerates mutant K-ras/p53-driven cholangiocarcinoma

2020 ◽  
Vol 318 (3) ◽  
pp. G419-G427 ◽  
Author(s):  
Tatsuhide Nabeshima ◽  
Shin Hamada ◽  
Keiko Taguchi ◽  
Yu Tanaka ◽  
Ryotaro Matsumoto ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cancer Progression ◽  
Stress Responses ◽  
Target Genes ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Related Factor ◽  
Loss Of Function ◽  
P53 Expression ◽  
Nrf2 Activation

The activation of the Kelch-like ECH-associated protein 1 (Keap1)-NF-E2-related factor 2 (Nrf2) pathway contributes to cancer progression in addition to oxidative stress responses. Loss-of-function Keap1 mutations were reported to activate Nrf2, leading to cancer progression. We examined the effects of Keap1 deletion in a cholangiocarcinoma mouse model using a mutant K-ras/ p53 mouse. Introduction of the Keap1 deletion into liver-specific mutant K-ras/ p53 expression resulted in the formation of invasive cholangiocarcinoma. Comprehensive analyses of the gene expression profiles identified broad upregulation of Nrf2-target genes such as Nqo1 and Gstm1 in the Keap1-deleted mutant K-ras/ p53 expressing livers, accompanied by upregulation of cholangiocyte-related genes. Among these genes, the transcriptional factor Sox9 was highly expressed in the dysplastic bile duct. The Keap-Nrf2-Sox9 axis might serve as a novel therapeutic target for cholangiocarcinoma. NEW & NOTEWORTHY The Keap1-Nrf2 system has a wide variety of effects in addition to the oxidative stress response in cancer cells. Addition of the liver-specific Keap1 deletion to mice harboring mutant K-ras and p53 accelerated cholangiocarcinoma formation, together with the hallmarks of Nrf2 activation. This process involved the expansion of Sox9-positive cells, indicating increased differentiation toward the cholangiocyte phenotype.

scholarly journals DR1440 is a potential iron efflux protein involved in maintenance of iron homeostasis and resistance of Deinococcus radiodurans to oxidative stress

PLoS ONE ◽  
2018 ◽  
Vol 13 (8) ◽  
pp. e0202287 ◽  
Author(s):  
Shang Dai ◽  
Ye Jin ◽  
Tao Li ◽  
Yulan Weng ◽  
Xiaolin Xu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Iron Homeostasis ◽  
Deinococcus Radiodurans

scholarly journals Critical Role of Zinc as Either an Antioxidant or a Prooxidant in Cellular Systems

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Sung Ryul Lee
Keyword(s):  
Oxidative Stress ◽  
Zinc Deficiency ◽  
Metal Binding ◽  
Inflammatory Responses ◽  
Binding Capacity ◽  
Critical Role ◽  
Cellular Systems ◽  
Oxidative Stresses ◽  
Dual Action

Zinc is recognized as an essential trace metal required for human health; its deficiency is strongly associated with neuronal and immune system defects. Although zinc is a redox-inert metal, it functions as an antioxidant through the catalytic action of copper/zinc-superoxide dismutase, stabilization of membrane structure, protection of the protein sulfhydryl groups, and upregulation of the expression of metallothionein, which possesses a metal-binding capacity and also exhibits antioxidant functions. In addition, zinc suppresses anti-inflammatory responses that would otherwise augment oxidative stress. The actions of zinc are not straightforward owing to its numerous roles in biological systems. It has been shown that zinc deficiency and zinc excess cause cellular oxidative stress. To gain insights into the dual action of zinc, as either an antioxidant or a prooxidant, and the conditions under which each role is performed, the oxidative stresses that occur in zinc deficiency and zinc overload in conjunction with the intracellular regulation of free zinc are summarized. Additionally, the regulatory role of zinc in mitochondrial homeostasis and its impact on oxidative stress are briefly addressed.

Irinotecan Resistance – In Search of New Markers in CRC.

2021 ◽  
Author(s):  
Jakub Kryczka ◽  
Joanna Boncela
Keyword(s):  
Drug Resistance ◽  
Cell Lines ◽  
Expression Profiles ◽  
Resistance Mechanism ◽  
Interaction Network ◽  
In Vitro Study ◽  
Cancer Drug ◽  
New Genes

Abstract Colorectal cancer (CRC) is one of the most prominent causes of cancer death worldwide. Chemotherapeutic regimens consisting of different drugs combinations such as 5-fluorouracil, and oxaliplatin (FOLFOX) or irinotecan (FOLFIRI) have been proven successful in the treatment of CRC. However, chemotherapy often leads to the acquisition of cancer drug resistance followed by metastasis and in the aftermath therapeutic failure. The molecular mechanism responsible for drug resistance is still unclear. The systemic search for new biomarkers of this phenomenon may identify new genes and pathways. To understand the drug resistance mechanism in CRC, the in vitro study based on the molecular analysis of drug-sensitive cells lines vs drug-resistant cells lines has been used. In our study to bridge the gap between in vitro and in vivo study, we compared the expression profiles of cell lines and patient samples from the publicly available database to select the new candidate genes for irinotecan resistance. Using The Gene Expression Omnibus (GEO) database of CRC cell lines (HT29, HTC116, LoVo, and their respective irinotecan-resistant variants) and patient samples (GSE42387, GSE62080, and GSE18105) we compared the changes in the mRNA expression profile of the main genes involved in irinotecan body’s processing, such as transport out of the cells and metabolism. Furthermore, using a protein-protein interaction network of differently expressed genes between FOLFIRI resistant and sensitive CRC patients, we have selected top networking proteins (upregulated: NDUFA2, SDHD, LSM5, DCAF4, and COX10, downregulated: RBM8A, TIMP1, QKI, TGOLN2, and PTGS2). Our analysis provided several potential irinotecan resistance markers, previously not described as such.

scholarly journals Effect of Sulforaphane and 5-Aza-2’-Deoxycytidine on Melanoma Cell Growth

Medicines ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 71 ◽  
Author(s):  
Tung-chin Chiang ◽  
Brian Koss ◽  
L. Joseph Su ◽  
Charity L. Washam ◽  
Stephanie D. Byrum ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Growth ◽  
Gene Transcription ◽  
Melanoma Cell ◽  
Dna Methyltransferase ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Epigenetic Modifications ◽  
Driving Mechanism ◽  
Epigenetic Drug

Background: UV exposure-induced oxidative stress is implicated as a driving mechanism for melanoma. Increased oxidative stress results in DNA damage and epigenetic dysregulation. Accordingly, we explored whether a low dose of the antioxidant sulforaphane (SFN) in combination with the epigenetic drug 5-aza-2’-deoxycytidine (DAC) could slow melanoma cell growth. SFN is a natural bioactivated product of the cruciferous family, while DAC is a DNA methyltransferase inhibitor. Methods: Melanoma cell growth characteristics, gene transcription profiles, and histone epigenetic modifications were measured after single and combination treatments with SFN and DAC. Results: We detected melanoma cell growth inhibition and specific changes in gene expression profiles upon combinational treatments with SFN and DAC, while no significant alterations in histone epigenetic modifications were observed. Dysregulated gene transcription of a key immunoregulator cytokine—C-C motif ligand 5 (CCL-5)—was validated. Conclusions: These results indicate a potential combinatorial effect of a dietary antioxidant and an FDA-approved epigenetic drug in controlling melanoma cell growth.

scholarly journals Perfluorooctanesulfonic Acid and Perfluorohexanesulfonic Acid Alter the Blood Lipidome and the Hepatic Proteome in a Murine Model of Diet-Induced Obesity

2020 ◽  
Vol 178 (2) ◽  
pp. 311-324
Author(s):  
Marisa Pfohl ◽  
Lishann Ingram ◽  
Emily Marques ◽  
Adam Auclair ◽  
Benjamin Barlock ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lipid Metabolism ◽  
Expression Profiles ◽  
Environmental Toxicants ◽  
High Fat ◽  
High Carbohydrate ◽  
Lipid Species ◽  
Perfluorooctanesulfonic Acid ◽  
The Impact ◽  
And Oxidative Stress

Abstract Perfluoroalkyl substances (PFAS) represent a family of environmental toxicants that have infiltrated the living world. This study explores diet-PFAS interactions and the impact of perfluorooctanesulfonic acid (PFOS) and perfluorohexanesulfonic (PFHxS) on the hepatic proteome and blood lipidomic profiles. Male C57BL/6J mice were fed with either a low-fat diet (10.5% kcal from fat) or a high fat (58% kcal from fat) high carbohydrate (42 g/l) diet with or without PFOS or PFHxS in feed (0.0003% wt/wt) for 29 weeks. Lipidomic, proteomic, and gene expression profiles were determined to explore lipid outcomes and hepatic mechanistic pathways. With administration of a high-fat high-carbohydrate diet, PFOS and PFHxS increased hepatic expression of targets involved in lipid metabolism and oxidative stress. In the blood, PFOS and PFHxS altered serum phosphatidylcholines, phosphatidylethanolamines, plasmogens, sphingomyelins, and triglycerides. Furthermore, oxidized lipid species were enriched in the blood lipidome of PFOS and PFHxS treated mice. These data support the hypothesis that PFOS and PFHxS increase the risk of metabolic and inflammatory disease induced by diet, possibly by inducing dysregulated lipid metabolism and oxidative stress.

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