Browsing by Subject "OXIDATIVE STRESS"

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  • McWilliams, Thomas G.; Prescott, Alan R.; Villarejo-Zori, Beatriz; Ball, Graeme; Boya, Patricia; Ganleya, Ian G. (2019)
    Photoreception is pivotal to our experience and perception of the natural world; hence the eye is of prime importance for most vertebrate animals to sense light. Central to visual health is mitochondrial homeostasis, and the selective autophagic turnover of mitochondria (mitophagy) is predicted to play a key role here. Despite studies that link aberrant mitophagy to ocular dysfunction, little is known about the prevalence of basal mitophagy, or its relationship to general autophagy, in the visual system. In this study, we utilize the mito-QC mouse and a closely related general macroautophagy reporter model to profile basal mitophagy and macroautophagy in the adult and developing eye. We report that ocular macroautophagy is widespread, but surprisingly mitophagy does not always follow the same pattern of occurrence. We observe low levels of mitophagy in the lens and ciliary body, in stark contrast to the high levels of general MAP1LC3-dependent macroautophagy in these regions. We uncover a striking reversal of this process in the adult retina, where mitophagy accounts for a larger degree of the macroautophagy taking place, specifically in the photoreceptor neurons of the outer nuclear layer. We also show the developmental regulation of autophagy in a variety of ocular tissues. In particular, mitophagy in the adult mouse retina is reversed in localization during the latter stages of development. Our work thus defines the landscape of mitochondrial homeostasis in the mammalian eye, and in doing so highlights the selective nature of autophagy in vivo and the specificity of the reporters used.
  • Kaurilind, Eve; Xu, Enjun; Brosche, Mikael (2015)
    Background: To survive in a changing environment plants constantly monitor their surroundings. In response to several stresses and during photorespiration plants use reactive oxygen species as signaling molecules. The Arabidopsis thaliana catalase2 (cat2) mutant lacks a peroxisomal catalase and under photorespiratory conditions accumulates H2O2, which leads to activation of cell death. Methods: A cat2 double mutant collection was generated through crossing and scored for cell death in different assays. Selected double mutants were further analyzed for photosynthetic performance and H2O2 accumulation. Results: We used a targeted mutant analysis with more than 50 cat2 double mutants to investigate the role of stress hormones and other defense regulators in H2O2 -mediated cell death. Several transcription factors (AS1, MYB30, MYC2, WRKY70), cell death regulators (RCD1, DND1) and hormone regulators (AXR1, ERA1, SID2, EDS1, SGT1b) were essential for execution of cell death in cat2. Genetic loci required for cell death in cat2 was compared with regulators of cell death in spontaneous lesion mimic mutants and led to the identification of a core set of plant cell death regulators. Analysis of gene expression data from cat2 and plants undergoing cell death revealed similar gene expression profiles, further supporting the existence of a common program for regulation of plant cell death. Conclusions: Our results provide a genetic framework for further study on the role of H2O2 in regulation of cell death. The hormones salicylic acid, jasmonic acid and auxin, as well as their interaction, are crucial determinants of cell death regulation.
  • LifeLines Cohort Study; Sung, Yun Ju; Heikkinen, Sami; Koistinen, Heikki A. (2019)
    Elevated blood pressure (BP), a leading cause of global morbidity and mortality, is influenced by both genetic and lifestyle factors. Cigarette smoking is one such lifestyle factor. Across five ancestries, we performed a genome-wide gene-smoking interaction study of mean arterial pressure (MAP) and pulse pressure (PP) in 129 913 individuals in stage 1 and follow-up analysis in 480 178 additional individuals in stage 2. We report here 136 loci significantly associated with MAP and/or PP. Of these, 61 were previously published through main-effect analysis of BP traits, 37 were recently reported by us for systolic BP and/or diastolic BP through gene-smoking interaction analysis and 38 were newly identified (P <5 x 10(-8), false discovery rate <0.05). We also identified nine new signals near known loci. Of the 136 loci, 8 showed significant interaction with smoking status. They include CSMD1 previously reported for insulin resistance and BP in the spontaneously hypertensive rats. Many of the 38 new loci show biologic plausibility for a role in BP regulation. SLC26A7 encodes a chloride/bicarbonate exchanger expressed in the renal outer medullary collecting duct. AVPR1A is widely expressed, including in vascular smooth muscle cells, kidney, myocardium and brain. FHAD1 is a long non-coding RNA overexpressed in heart failure. TMEM51 was associated with contractile function in cardiomyocytes. CASP9 plays a central role in cardiomyocyte apoptosis. Identified only in African ancestry were 30 novel loci. Our findings highlight the value of multi-ancestry investigations, particularly in studies of interaction with lifestyle factors, where genomic and lifestyle differences may contribute to novel findings.
  • Wang, Shuyuan; Alenius, Harri; El-Nezami, Hani; Karisola, Piia (2022)
    Titanium dioxide (TiO2) and zinc oxide (ZnO) nanoparticles (NPs) have attracted a great deal of attention due to their excellent electrical, optical, whitening, UV-adsorbing and bactericidal properties. The extensive production and utilization of these NPs increases their chances of being released into the environment and conferring unintended biological effects upon exposure. With the increasingly prevalent use of the omics technique, new data are burgeoning which provide a global view on the overall changes induced by exposures to NPs. In this review, we provide an account of the biological effects of ZnO and TiO2 NPs arising from transcriptomics in in vivo and in vitro studies. In addition to studies on humans and mice, we also describe findings on ecotoxicology-related species, such as Danio rerio (zebrafish), Caenorhabditis elegans (nematode) or Arabidopsis thaliana (thale cress). Based on evidence from transcriptomics studies, we discuss particle-induced biological effects, including cytotoxicity, developmental alterations and immune responses, that are dependent on both material-intrinsic and acquired/transformed properties. This review seeks to provide a holistic insight into the global changes induced by ZnO and TiO2 NPs pertinent to human and ecotoxicology.
  • Tuomisto, Karolina; Palmu, Joonatan; Long, Tao; Watrous, Jeramie D.; Mercader, Kysha; Lagerborg, Kim A.; Andres, Allen; Salmi, Marko; Jalkanen, Sirpa; Vasan, Ramachandran S.; Inouye, Michael; Havulinna, Aki S.; Tuomilehto, Jaakko; Jousilahti, Pekka; Niiranen, Teemu J.; Cheng, Susan; Jain, Mohit; Salomaa, Veikko (2022)
    Introduction Peptide markers of inflammation have been associated with the development of type 2 diabetes. The role of upstream, lipid-derived mediators of inflammation such as eicosanoids, remains less clear. The aim of this study was to examine whether eicosanoids are associated with incident type 2 diabetes. Research design & methods In the FINRISK (Finnish Cardiovascular Risk Study) 2002 study, a population-based sample of Finnish men and women aged 25-74 years, we used directed, non-targeted liquid chromatography-mass spectrometry to identify 545 eicosanoids and related oxylipins in the participants' plasma samples (n=8292). We used multivariable-adjusted Cox regression to examine associations between eicosanoids and incident type 2 diabetes. The significant independent findings were replicated in the Framingham Heart Study (FHS, n=2886) and Dietary, Lifestyle and Genetic determinants of Obesity and Metabolic syndrome (DILGOM) 2007 (n=3905). Together, these three cohorts had 1070 cases of incident type 2 diabetes. Results In the FINRISK 2002 cohort, 76 eicosanoids were associated individually with incident type 2 diabetes. We identified three eicosanoids independently associated with incident type 2 diabetes using stepwise Cox regression with forward selection and a Bonferroni-corrected inclusion threshold. A three-eicosanoid risk score produced an HR of 1.56 (95% CI 1.41 to 1.72) per 1 SD increment for risk of incident diabetes. The HR for comparing the top quartile with the lowest was 2.80 (95% CI 2.53 to 3.07). In the replication analyses, the three-eicosanoid risk score was significant in FHS (HR 1.24 (95% CI 1.10 to 1.39, p Conclusions Plasma eicosanoid profiles predict incident type 2 diabetes and the clearest signals replicate in three independent cohorts. Our findings give new information on the biology underlying type 2 diabetes and suggest opportunities for early identification of people at risk.
  • Pascual, Jesus; Rahikainen, Moona; Angeleri, Martina; Alegre, Sara; Gossens, Richard; Shapiguzov, Alexey; Heinonen, Arttu; Trotta, Andrea; Durian, Guido; Winter, Zsofia; Sinkkonen, Jari; Kangasjarvi, Jaakko; Whelan, James; Kangasjärvi, Saijaliisa (2021)
    Mitochondria are tightly embedded within metabolic and regulatory networks that optimize plant performance in response to environmental challenges. The best-known mitochondrial retrograde signaling pathway involves stress-induced activation of the transcription factor NAC DOMAIN CONTAINING PROTEIN 17 (ANAC017), which initiates protective responses to stress-induced mitochondrial dysfunction in Arabidopsis (Arabidopsis thaliana). Posttranslational control of the elicited responses, however, remains poorly understood. Previous studies linked protein phosphatase 2A subunit PP2A-B'gamma, a key negative regulator of stress responses, with reversible phosphorylation of ACONITASE 3 (ACO3). Here we report on ACO3 and its phosphorylation at Ser91 as key components of stress regulation that are induced by mitochondrial dysfunction. Targeted mass spectrometry-based proteomics revealed that the abundance and phosphorylation of ACO3 increased under stress, which required signaling through ANAC017. Phosphomimetic mutation at ACO3-Ser91 and accumulation of ACO3(S91D)-YFP promoted the expression of genes related to mitochondrial dysfunction. Furthermore, ACO3 contributed to plant tolerance against ultraviolet B (UV-B) or antimycin A-induced mitochondrial dysfunction. These findings demonstrate that ACO3 is both a target and mediator of mitochondrial dysfunction signaling, and critical for achieving stress tolerance in Arabidopsis leaves.
  • Eriksson, Mia D.; Eriksson, Johan G.; Kautiainen, Hannu; Salonen, Minna K.; Mikkola, Tuija M.; Kajantie, Eero; Wasenius, Niko; von Bonsdorff, Mikaela; Laine, Merja K. (2021)
    Background: Millions of people live with depression and its burden of disease. Depression has an increased comorbidity and mortality that has remained unexplained. Studies have reported connections between advanced glycation end products (AGEs) and various disease processes, including mental health. The present study evaluated associations between AGEs, depressive symptoms, and types of depressive symptoms. Methods: From the Helsinki Birth Cohort Study, 815 participants with a mean age of 76 years were recruited for this cross-sectional study. Characteristics regarding self-reported lifestyle and medical history, as well as blood tests were obtained along with responses regarding depressive symptoms according to the Beck Depression Inventory (BDI) and Mental Health Inventory-5. Each participant had their AGE level measured non-invasively with skin autofluorescence (SAF). Statistical analyses looked at relationships between types of depressive symptoms and AGE levels by sex. Results: Of women, 27% scored >= 10 on the BDI and 18% of men, respectively. Men had higher crude AGE levels (mean [standard deviation], arbitrary units) (2.49 [0.51]) compared to women (2.33 [0.46]) (p < 0.001). The highest crude AGE levels were found in those with melancholic depressive symptoms (2.61 [0.57]), followed by those with non-melancholic depressive symptoms (2.45 [0.45]) and those with no depressive symptoms (2.38 [0.49]) (p = 0.013). These findings remained significant in the fully adjusted model. Conclusions: The current study shows an association between depressive symptoms and higher AGE levels. The association is likely part of a multi-factorial effect, and hence no directionality, causality, or effect can be inferred solely based on the results of this study.
  • Noreikiene, Kristina; Kuparinen, Anna; Merilae, Juha (2017)
    Telomeres are highly conserved nucleoprotein structures which protect genome integrity. The length of telomeres is influenced by both genetic and environmental factors, but relatively little is known about how different hereditary and environmental factors interact in determining telomere length. We manipulated growth rates and timing of maturation by exposing full-sib nine-spined sticklebacks (Pungitius pungitius) to two different temperature treatments and quantified the effects of temperature treatments, sex, timing of maturation, growth rate and family (genetic influences) on telomere length. We did not find the overall effect of temperature treatment on the relative telomere length. However, we found that variation in telomere length was related to timing of maturation in a sex- and temperature-dependent manner. Telomere length was negatively related to age at maturation in elevated temperature and early maturing males and females differed in telomere length. Variation in growth rate did not explain any variation in telomere length. The broad sense heritability (h(2)) of telomere length was estimated at h(2) = 0.31 - 0.47, suggesting predominance of environmental over genetic determinants of telomere length variability. This study provides the first evidence that age at maturation together with factors associated with it are influencing telomere length in an ectotherm. Future studies are encouraged to identify the extent to which these results can be replicated in other ectotherms.
  • Gospodaryov, Dmytro; Strilbytska, Olha M.; Semaniuk, Uliana; Perkhulyn, Natalia; Rovenko, Bohdana M.; Yurkevych, Ihor S.; Barata, Ana G.; Dick, Tobias P.; Lushchak, Oleh; Jacobs, Howard T. (2020)
    Mitochondrial alternative NADH dehydrogenase (aNDH) was found to extend lifespan when expressed in the fruit fly. We have found that fruit flies expressing aNDH from Ciona intestinalis (NDX) had 17-71% lifespan prolongation on media with different protein-tocarbohydrate ratios except NDX-expressing males that had 19% shorter lifespan than controls on a high protein diet. NDX-expressing flies were more resistant to organic xenobiotics, 2,4-dichlorophenoxyacetic acid and alloxan, and inorganic toxicant potassium iodate, and partially to sodium molybdate treatments. On the other hand, NDX-expressing flies were more sensitive to catechol and sodium chromate. Enzymatic analysis showed that NDX-expressing males had higher glucose 6-phosphate dehydrogenase activity, whilst both sexes showed increased glutathione S-transferase activity.
  • Keuters, Meike Hedwig; Keksa-Goldsteine, Velta; Dhungana, Hiramani; Huuskonen, Mikko T.; Pomeshchik, Yuriy; Savchenko, Ekaterina; Korhonen, Paula K.; Singh, Yajuvinder; Wojciechowski, Sara; Lehtonen, Sarka; Kanninen, Katja M.; Malm, Tarja; Sirviö, Jouni; Muona, Anu; Koistinaho, Milla; Goldsteins, Gundars; Koistinaho, Jari (2021)
    Lipid peroxidation-initiated ferroptosis is an iron-dependent mechanism of programmed cell death taking place in neurological diseases. Here we show that a condensed benzo[b]thiazine derivative small molecule with an arylthiazine backbone (ADA-409-052) inhibits tert-Butyl hydroperoxide (TBHP)-induced lipid peroxidation (LP) and protects against ferroptotic cell death triggered by glutathione (GSH) depletion or glutathione peroxidase 4 (GPx4) inhibition in neuronal cell lines. In addition, ADA-409-052 suppresses pro-inflammatory activation of BV2 microglia and protects N2a neuronal cells from cell death induced by pro-inflammatory RAW 264.7 macrophages. Moreover, ADA-409-052 efficiently reduces infarct volume, edema and expression of pro-inflammatory genes in a mouse model of thromboembolic stroke. Targeting ferroptosis may be a promising therapeutic strategy in neurological diseases involving severe neuronal death and neuroinflammation.
  • Blein, Sophie; Bardel, Claire; Danjean, Vincent; McGuffog, Lesley; Healey, Sue; Barrowdale, Daniel; Lee, Andrew; Dennis, Joe; Kuchenbaecker, Karoline B.; Soucy, Penny; Terry, Mary Beth; Chung, Wendy K.; Goldgar, David E.; Buys, Saundra S.; Janavicius, Ramunas; Tihomirova, Laima; Tung, Nadine; Dorfling, Cecilia M.; van Rensburg, Elizabeth J.; Neuhausen, Susan L.; Ding, Yuan Chun; Gerdes, Anne-Marie; Ejlertsen, Bent; Nielsen, Finn C.; Hansen, Thomas V. O.; Osorio, Ana; Benitez, Javier; Andres Conejero, Raquel; Segota, Ena; Weitzel, Jeffrey N.; Thelander, Margo; Peterlongo, Paolo; Radice, Paolo; Pensotti, Valeria; Dolcetti, Riccardo; Bonanni, Bernardo; Peissel, Bernard; Zaffaroni, Daniela; Scuvera, Giulietta; Manoukian, Siranoush; Varesco, Liliana; Capone, Gabriele L.; Papi, Laura; Ottini, Laura; Yannoukakos, Drakoulis; Konstantopoulou, Irene; Garber, Judy; Hamann, Ute; Donaldson, Alan; Brady, Angela; Brewer, Carole; Foo, Claire; Evans, D. Gareth; Frost, Debra; Eccles, Diana; Douglas, Fiona; Cook, Jackie; Adlard, Julian; Barwell, Julian; Walker, Lisa; Izatt, Louise; Side, Lucy E.; Kennedy, M. John; Tischkowitz, Marc; Rogers, Mark T.; Porteous, Mary E.; Morrison, Patrick J.; Platte, Radka; Eeles, Ros; Davidson, Rosemarie; Hodgson, Shirley; Cole, Trevor; Godwin, Andrew K.; Isaacs, Claudine; Claes, Kathleen; De Leeneer, Kim; Meindl, Alfons; Gehrig, Andrea; Wappenschmidt, Barbara; Sutter, Christian; Engel, Christoph; Niederacher, Dieter; Steinemann, Doris; Plendl, Hansjoerg; Kast, Karin; Rhiem, Kerstin; Ditsch, Nina; Arnold, Norbert; Varon-Mateeva, Raymonda; Schmutzler, Rita K.; Preisler-Adams, Sabine; Markov, Nadja Bogdanova; Wang-Gohrke, Shan; de Pauw, Antoine; Lefol, Cedrick; Lasset, Christine; Leroux, Dominique; Rouleau, Etienne; Damiola, Francesca; Dreyfus, Helene; Barjhoux, Laure; Golmard, Lisa; Uhrhammer, Nancy; Bonadona, Valerie; Sornin, Valerie; Bignon, Yves-Jean; Carter, Jonathan; Van Le, Linda; Piedmonte, Marion; DiSilvestro, Paul A.; de la Hoya, Miguel; Caldes, Trinidad; Nevanlinna, Heli; Aittomaki, Kristiina; Jager, Agnes; van den Ouweland, Ans M. W.; Kets, Carolien M.; Aalfs, Cora M.; van Leeuwen, Flora E.; Hogervorst, Frans B. L.; Meijers-Heijboer, Hanne E. J.; Oosterwijk, Jan C.; van Roozendaal, Kees E. P.; Rookus, Matti A.; Devilee, Peter; van der Luijt, Rob B.; Olah, Edith; Diez, Orland; Teule, Alex; Lazaro, Conxi; Blanco, Ignacio; Del Valle, Jesus; Jakubowska, Anna; Sukiennicki, Grzegorz; Gronwald, Jacek; Lubinski, Jan; Durda, Katarzyna; Jaworska-Bieniek, Katarzyna; Agnarsson, Bjarni A.; Maugard, Christine; Amadori, Alberto; Montagna, Marco; Teixeira, Manuel R.; Spurdle, Amanda B.; Foulkes, William; Olswold, Curtis; Lindor, Noralane M.; Pankratz, Vernon S.; Szabo, Csilla I.; Lincoln, Anne; Jacobs, Lauren; Corines, Marina; Robson, Mark; Vijai, Joseph; Berger, Andreas; Fink-Retter, Anneliese; Singer, Christian F.; Rappaport, Christine; Kaulich, Daphne Geschwantler; Pfeiler, Georg; Tea, Muy-Kheng; Greene, Mark H.; Mai, Phuong L.; Rennert, Gad; Imyanitov, Evgeny N.; Mulligan, Anna Marie; Glendon, Gord; Andrulis, Irene L.; Tchatchou, Sandrine; Toland, Amanda Ewart; Pedersen, Inge Sokilde; Thomassen, Mads; Kruse, Torben A.; Jensen, Uffe Birk; Caligo, Maria A.; Friedman, Eitan; Zidan, Jamal; Laitman, Yael; Lindblom, Annika; Melin, Beatrice; Arver, Brita; Loman, Niklas; Rosenquist, Richard; Olopade, Olufunmilayo I.; Nussbaum, Robert L.; Ramus, Susan J.; Nathanson, Katherine L.; Domchek, Susan M.; Rebbeck, Timothy R.; Arun, Banu K.; Mitchell, Gillian; Karlan, Beth Y.; Lester, Jenny; Orsulic, Sandra; Stoppa-Lyonnet, Dominique; Thomas, Gilles; Simard, Jacques; Couch, Fergus J.; Offit, Kenneth; Easton, Douglas F.; Chenevix-Trench, Georgia; Antoniou, Antonis C.; Mazoyer, Sylvie; Phelan, Catherine M.; Sinilnikova, Olga M.; Cox, David G.; Breast Canc Family Registry; EMBRACE; GEMO Study Collaborators; HEBON (2015)
    Introduction: Individuals carrying pathogenic mutations in the BRCA1 and BRCA2 genes have a high lifetime risk of breast cancer. BRCA1 and BRCA2 are involved in DNA double-strand break repair, DNA alterations that can be caused by exposure to reactive oxygen species, a main source of which are mitochondria. Mitochondrial genome variations affect electron transport chain efficiency and reactive oxygen species production. Individuals with different mitochondrial haplogroups differ in their metabolism and sensitivity to oxidative stress. Variability in mitochondrial genetic background can alter reactive oxygen species production, leading to cancer risk. In the present study, we tested the hypothesis that mitochondrial haplogroups modify breast cancer risk in BRCA1/2 mutation carriers. Methods: We genotyped 22,214 (11,421 affected, 10,793 unaffected) mutation carriers belonging to the Consortium of Investigators of Modifiers of BRCA1/2 for 129 mitochondrial polymorphisms using the iCOGS array. Haplogroup inference and association detection were performed using a phylogenetic approach. ALTree was applied to explore the reference mitochondrial evolutionary tree and detect subclades enriched in affected or unaffected individuals. Results: We discovered that subclade T1a1 was depleted in affected BRCA2 mutation carriers compared with the rest of clade T (hazard ratio (HR) = 0.55; 95% confidence interval (CI), 0.34 to 0.88; P = 0.01). Compared with the most frequent haplogroup in the general population (that is, H and T clades), the T1a1 haplogroup has a HR of 0.62 (95% CI, 0.40 to 0.95; P = 0.03). We also identified three potential susceptibility loci, including G13708A/rs28359178, which has demonstrated an inverse association with familial breast cancer risk. Conclusions: This study illustrates how original approaches such as the phylogeny-based method we used can empower classical molecular epidemiological studies aimed at identifying association or risk modification effects.
  • Ousaaid, Driss; Ghouizi, Asmae El; Laaroussi, Hassan; Bakour, Meryem; Mechchate, Hamza; Es-safi, Imane; Kamaly, Omkulthom Al; Saleh, Asmaa; Conte, Raffaele; Lyoussi, Badiaa; El Arabi, Ilham (2022)
    This study aims to examine the ability of apple vinegar on phenylhydrazine (PHZ)-induced hemolytic anemia in Wistar rats. In vitro, phenolic and flavonoid content and antioxidant activity were determined. In vivo, phenylhydrazine (10 mg/kg) was injected intravenously into rats for 4 days and then treated with apple vinegar daily by gavage (1 mL/kg) for five weeks. high level of polyphenols and flavonoids (90 +/- 1.66 mg GAE/100 mL and 7.29 +/- 0.23 mg QE/100 mL, respectively) were found in the apple vinegar which gives it a good ability to scavenge free radicals (TAC = 4.22 +/- 0.18 mg AAE/100 mL and DPPH, IC50 = 0.49 +/- 0.004 mu L/ml). The phytochemical composition of apple vinegar revealed the presence of numerous bioactive compounds including arbutin, apigenin, sinapic, ferulic and trans-ferulic acids. The major antioxidant components in apple vinegar were ferulic and trans-ferulic acids (40% and 43%, respectively). PHZ treatment induced changes in platelets, blood cell count, mean corpuscular volume, hemoglobin concentration and mean capsulated hemoglobin. However, the co-administration of apple vinegar revealed its capacity to ameliorate the changes induced by phenylhydrazine. Therefore, apple vinegar use could have a positive impact on the prevention of hemolytic anemia induced by phenylhydrazine due to the antioxidant properties of its major components.
  • Korhonen, Eveliina; Hytti, Maria; Piippo, Niina; Kaarniranta, Kai; Kauppinen, Anu (2021)
    Age-related macular degeneration (AMD) is a severe retinal eye disease where dysfunctional mitochondria and damaged mitochondrial DNA in retinal pigment epithelium (RPE) have been demonstrated to underlie the pathogenesis of this devastating disease. In the present study, we aimed to examine whether damaged mitochondria induce inflammasome activation in human RPE cells. Therefore, ARPE-19 cells were primed with IL-1 alpha and exposed to the mitochondrial electron transport chain complex III inhibitor, antimycin A. We found that antimycin A-induced mitochondrial dysfunction caused caspase-1-dependent inflammasome activation and subsequent production of mature IL-1 beta and IL-18 in human RPE cells. AIM2 and NLRP3 appeared to be the responsible inflammasome receptors upon antimycin A-induced mitochondrial damage. We aimed at verifying our findings using hESC-RPE cells but antimycin A was absorbed by melanin. Therefore, results were repeated on D407 RPE cell cultures. Antimycin A-induced mitochondrial and NADPH oxidase-dependent ROS production occurred upstream of inflammasome activation, whereas K+ efflux was not required for inflammasome activation in antimycin A-treated human RPE cells. Collectively, our data emphasize that dysfunctional mitochondria regulate the assembly of inflammasome multiprotein complexes in the human RPE cells. The present study associates AIM2 with the pathogenesis of AMD.
  • Taavitsainen, Eveliina; Kortesoja, Maarit; Bruun, Tanja; Johansson, Niklas G; Hanski, Leena (2020)
    Antibiotic-tolerant persister bacteria involve frequent treatment failures, relapsing infections and the need for extended antibiotic treatment. The virulence of an intracellular human pathogen C. pneumoniae is tightly linked to its propensity for persistence and means for its chemosensitization are urgently needed. In the current work, persistence of C. pneumoniae clinical isolate CV6 was studied in THP-1 macrophages using quantitative PCR and quantitative culture. A dibenzocyclooctadiene lignan schisandrin reverted C. pneumoniae persistence and promoted productive infection. The concomitant administration of schisandrin and azithromycin resulted in significantly improved bacterial eradication compared to sole azithromycin treatment. In addition, the closely related lignan schisandrin C was superior to azithromycin in eradicating the C. pneumoniae infection from the macrophages. The observed chemosensitization of C. pneumoniae was associated with the suppression of cellular glutathione pools by the lignans, implying to a previously unknown aspect of chlamydia-host interactions. These data indicate that schisandrin lignans induce a phenotypic switch in C. pneumoniae, promoting the productive and antibiotic-susceptible phenotype instead of persistence. By this means, these medicinal plant -derived compounds show potential as adjuvant therapies for intracellular bacteria resuscitation.
  • Ahola, Aila J.; Saraheimo, Markku; Freese, Riitta; Forsblom, Carol; Mäkimattila, Sari; Groop, Per-Henrik; FinnDiane Study Grp (2017)
    Aims: Inflammation plays an important role in the pathogenesis of cardiovascular diseases. Diet, as a modifiable risk factor, may in turn impact systemic inflammation. We therefore assessed whether adherence to the dietary recommendations is associated with high-sensitivity C-reactive protein (hs-CRP) concentrations in type 1 diabetes. Methods: Cross-sectional data from 677 FinnDiane study participants (48% men, mean +/- standard deviation age 46 +/- 13 years) were included. Dietary intake was assessed with a self-administered questionnaire. A diet score, with higher values denoting better adherence to the recommendations, was calculated. Serum hs-CRP concentration was measured, and individuals with hs-CRP <1.0 mg/l, and hs-CRP > 3.0 but <10.0 mg/l were compared. Results: Men and women with high hs-CRP had higher BMI, waist circumference, and triglyceride concentration, but lower HDL-cholesterol concentration. Adjusted for BMI, mean diet score was higher in the low hs-CRP group, both in men (10.8 +/- 3.6 vs. 9.9 +/- 3.8, p = 0.023) and women (12.7 +/- 3.4 vs. 11.6 +/- 3.5, p = 0.021). After further adjustments with potential confounding factors, the difference remained significant only in men. Conclusions: A diet that more closely adheres to the dietary recommendations is associated with lower hs-CRP in men. A prudent diet may help reduce systemic inflammation in type 1 diabetes. (C) 2017 Elsevier B.V. All rights reserved.
  • Seppala, Ilkka; Kleber, Marcus E.; Bevan, Steve; Lyytikainen, Leo-Pekka; Oksala, Niku; Hernesniemi, Jussi A.; Makela, Kari-Matti; Rothwell, Peter M.; Sudlow, Cathie; Dichgans, Martin; Mononen, Nina; Vlachopoulou, Efthymia; Sinisalo, Juha; Delgado, Graciela E.; Laaksonen, Reijo; Koskinen, Tuomas; Scharnagl, Hubert; Kahonen, Mika; Markus, Hugh S.; Maez, Winfried; Lehtimaki, Terho (2016)
    Asymmetric and symmetric dimethylarginines (ADMA and SDMA) impair nitric oxide bioavailability and have been implicated in the pathogenesis of atrial fibrillation (AF). Alanine-glyoxylate aminotransferase 2 (AGXT2) is the only enzyme capable of metabolizing both of the dimethylarginines. We hypothesized that two functional AGXT2 missense variants (rs37369, V140I; rs16899974, V498L) are associated with AF and its cardioembolic complications. Association analyses were conducted using 1,834 individulas with AF and 7,159 unaffected individuals from two coronary angiography cohorts and a cohort comprising patients undergoing clinical exercise testing. In coronary angiography patients without structural heart disease, the minor A allele of rs16899974 was associated with any AF (OR = 2.07, 95% CI 1.59-2.68), and with paroxysmal AF (OR = 1.98, 95% CI 1.44-2.74) and chronic AF (OR = 2.03, 95% CI 1.35-3.06) separately. We could not replicate the association with AF in the other two cohorts. However, the A allele of rs16899974 was nominally associated with ischemic stroke risk in the meta-analysis of WTCCC2 ischemic stroke cohorts (3,548 cases, 5,972 controls) and with earlier onset of first-ever ischemic stroke (360 cases) in the cohort of clinical exercise test patients. In conclusion, AGXT2 variations may be involved in the pathogenesis of AF and its age-related thromboembolic complications.
  • Fenstad, Anette A.; Bustnes, Jan O.; Lierhagen, Syverin; Gabrielsen, Kristin M.; Öst, Markus; Jaatinen, Kim; Hanssen, Sveinn A.; Moe, Borge; Jenssen, Bjorn M.; Krokje, Ase (2017)
    We report blood and feather concentrations of elements in the Baltic Sea and Arctic population of common eiders (Somateria mollissima). The endangered Baltic Sea population of eiders was demonstrably affected by element pollution in the 1990s. While blood concentrations of Hg were higher in Baltic breeding eiders, blood Se, As and Cd concentrations were higher in Arctic eiders. Blood concentrations of Pb, Cr, Zn and Cu did not differ between the two populations. While blood Pb concentrations had declined in Baltic eiders since the 1990s, Hg concentrations had not declined, and were above concentrations associated with adverse oxidative effects in other bird species. Inconsistent with blood concentrations, feather concentrations suggested that Pb, Zn, and Cd exposure was higher in Baltic eiders, and that Hg exposure was higher in Arctic eiders. Our study thus emphasizes the need for comprehensive evaluation of toxic element status, covering the annual cycle of a species. (C) 2016 Elsevier Ltd. All rights reserved.
  • Hogfors, Hedvig; Motwani, Nisha H.; Hajdu, Susanna; El-Shehawy, Rehab; Holmborn, Towe; Vehmaa, Anu; Engström-Öst, Jonna; Brutemark, Andreas; Gorokhova, Elena (2014)
  • ARIA Grp; Bousquet, Jean; Anto, Josep M.; Czarlewski, Wienczyslawa; Haahtela, Tari; Zuberbier, Torsten; Erhola, Marina (2021)
    Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.