| 1. |
- Alijagic, Andi, 1992-, et al.
(författare)
-
Metabolic and phenotypic changes induced by PFAS exposure in two human hepatocyte cell models
- 2024
-
Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 190
-
Tidskriftsartikel (refereegranskat)abstract
- PFAS are ubiquitous industrial chemicals with known adverse health effects, particularly on the liver. The liver, being a vital metabolic organ, is susceptible to PFAS-induced metabolic dysregulation, leading to conditions such as hepatotoxicity and metabolic disturbances. In this study, we investigated the phenotypic and metabolic responses of PFAS exposure using two hepatocyte models, HepG2 (male cell line) and HepaRG (female cell line), aiming to define phenotypic alterations, and metabolic disturbances at the metabolite and pathway levels. The PFAS mixture composition was selected based on epidemiological data, covering a broad concentration spectrum observed in diverse human populations. Phenotypic profiling by Cell Painting assay disclosed predominant effects of PFAS exposure on mitochondrial structure and function in both cell models as well as effects on F-actin, Golgi apparatus, and plasma membrane-associated measures. We employed comprehensive metabolic characterization using liquid chromatography combined with high-resolution mass spectrometry (LC-HRMS). We observed dose-dependent changes in the metabolic profiles, particularly in lipid, steroid, amino acid and sugar and carbohydrate metabolism in both cells as well as in cell media, with HepaRG cell line showing a stronger metabolic response. In cells, most of the bile acids, acylcarnitines and free fatty acids showed downregulation, while medium-chain fatty acids and carnosine were upregulated, while the cell media showed different response especially in relation to the bile acids in HepaRG cell media. Importantly, we observed also nonmonotonic response for several phenotypic features and metabolites. On the pathway level, PFAS exposure was also associated with pathways indicating oxidative stress and inflammatory responses. Taken together, our findings on PFAS-induced phenotypic and metabolic disruptions in hepatocytes shed light on potential mechanisms contributing to the broader comprehension of PFAS-related health risks.
|
|
| 2. |
- Geng, Dawei, 1986-, et al.
(författare)
-
Effect of perfluorooctanesulfonic acid (PFOS) on the liver lipid metabolism of the developing chicken embryo
- 2019
-
Ingår i: Ecotoxicology and Environmental Safety. - : Elsevier. - 0147-6513 .- 1090-2414. ; 170, s. 691-698
-
Tidskriftsartikel (refereegranskat)abstract
- Perfluorooctanesulfonate (PFOS) is a well-known contaminant in the environment and it has shown to disrupt multiple biological pathways, particularly those related with lipid metabolism. In this study, we have studied the impact of in ovo exposure to PFOS on lipid metabolism in livers in developing chicken embryos using lipidomics for detailed characterization of the liver lipidome. We used an avian model (Gallus gallus domesticus) for in ovo treatment at two levels of PFOS. The lipid profile of the liver of the embryo was investigated by ultra-high performance liquid chromatography combined with quadrupole-time-of-flight mass spectrometry and by gas chromatography mass spectrometry. Over 170 lipids were identified, covering phospholipids, ceramides, di- and triacylglycerols, cholesterol esters and fatty acid composition of the lipids. The PFOS exposure caused dose dependent changes in the lipid levels, which included upregulation of specific phospholipids associated with the phosphatidylethanolamine N-methyltransferase (PEMT) pathway, triacylglycerols with low carbon number and double bond count as well as of lipotoxic ceramides and diacylglycerols. Our data suggest that at lower levels of exposure, mitochondrial fatty acid β-oxidation is suppressed while the peroxisomal fatty acid β -oxidation is increased. At higher doses, however, both β -oxidation pathways are upregulated.
|
|
| 3. |
- Alijagic, Andi, 1992-, et al.
(författare)
-
A Novel Nanosafety Approach Using Cell Painting, Metabolomics, and Lipidomics Captures the Cellular and Molecular Phenotypes Induced by the Unintentionally Formed Metal-Based (Nano)Particles
- 2023
-
Ingår i: Cells. - : MDPI. - 2073-4409. ; 12:2
-
Tidskriftsartikel (refereegranskat)abstract
- Additive manufacturing (AM) or industrial 3D printing uses cutting-edge technologies and materials to produce a variety of complex products. However, the effects of the unintentionally emitted AM (nano)particles (AMPs) on human cells following inhalation, require further investigations. The physicochemical characterization of the AMPs, extracted from the filter of a Laser Powder Bed Fusion (L-PBF) 3D printer of iron-based materials, disclosed their complexity, in terms of size, shape, and chemistry. Cell Painting, a high-content screening (HCS) assay, was used to detect the subtle morphological changes elicited by the AMPs at the single cell resolution. The profiling of the cell morphological phenotypes, disclosed prominent concentration-dependent effects on the cytoskeleton, mitochondria, and the membranous structures of the cell. Furthermore, lipidomics confirmed that the AMPs induced the extensive membrane remodeling in the lung epithelial and macrophage co-culture cell model. To further elucidate the biological mechanisms of action, the targeted metabolomics unveiled several inflammation-related metabolites regulating the cell response to the AMP exposure. Overall, the AMP exposure led to the internalization, oxidative stress, cytoskeleton disruption, mitochondrial activation, membrane remodeling, and metabolic reprogramming of the lung epithelial cells and macrophages. We propose the approach of integrating Cell Painting with metabolomics and lipidomics, as an advanced nanosafety methodology, increasing the ability to capture the cellular and molecular phenotypes and the relevant biological mechanisms to the (nano)particle exposure.
|
|
| 4. |
- Alijagic, Andi, 1992-, et al.
(författare)
-
Immunotoxic, genotoxic, and endocrine disrupting impacts of polyamide microplastic particles and chemicals
- 2024
-
Ingår i: Environment International. - : Elsevier. - 0160-4120 .- 1873-6750. ; 183
-
Tidskriftsartikel (refereegranskat)abstract
- Due to their exceptional properties and cost effectiveness, polyamides or nylons have emerged as widely used materials, revolutionizing diverse industries, including industrial 3D printing or additive manufacturing (AM). Powder-based AM technologies employ tonnes of polyamide microplastics to produce complex components every year. However, the lack of comprehensive toxicity assessment of particulate polyamides and polyamide-associated chemicals, especially in the light of the global microplastics crisis, calls for urgent action. This study investigated the physicochemical properties of polyamide-12 microplastics used in AM, and assessed a number of toxicity endpoints focusing on inflammation, immunometabolism, genotoxicity, aryl hydrocarbon receptor (AhR) activation, endocrine disruption, and cell morphology. Specifically, microplastics examination by means of field emission scanning electron microscopy revealed that work flow reuse of material created a fraction of smaller particles with an average size of 1-5 µm, a size range readily available for uptake by human cells. Moreover, chemical analysis by means of gas chromatography high-resolution mass spectrometry detected several polyamide-associated chemicals including starting material, plasticizer, thermal stabilizer/antioxidant, and migrating slip additive. Even if polyamide particles and chemicals did not induce an acute inflammatory response, repeated and prolonged exposure of human primary macrophages disclosed a steady increase in the levels of proinflammatory chemokine Interleukin-8 (IL-8/CXCL-8). Moreover, targeted metabolomics disclosed that polyamide particles modulated the kynurenine pathway and some of its key metabolites. The p53-responsive luciferase reporter gene assay showed that particles per se were able to activate p53, being indicative of a genotoxic stress. Polyamide-associated chemicals triggered moderate activation of AhR and elicited anti-androgenic activity. Finally, a high-throughput and non-targeted morphological profiling by Cell Painting assay outlined major sites of bioactivity of polyamide-associated chemicals and indicated putative mechanisms of toxicity in the cells. These findings reveal that the increasing use of polyamide microplastics may pose a potential health risk for the exposed individuals, and it merits more attention.
|
|
| 5. |
- Alijagic, Andi, 1992-, et al.
(författare)
-
Particle Safety Assessment in Additive Manufacturing : From Exposure Risks to Advanced Toxicology Testing.
- 2022
-
Ingår i: Frontiers in Toxicology. - : Frontiers Media S.A.. - 2673-3080. ; 4
-
Forskningsöversikt (refereegranskat)abstract
- Additive manufacturing (AM) or industrial three-dimensional (3D) printing drives a new spectrum of design and production possibilities; pushing the boundaries both in the application by production of sophisticated products as well as the development of next-generation materials. AM technologies apply a diversity of feedstocks, including plastic, metallic, and ceramic particle powders with distinct size, shape, and surface chemistry. In addition, powders are often reused, which may change the particles' physicochemical properties and by that alter their toxic potential. The AM production technology commonly relies on a laser or electron beam to selectively melt or sinter particle powders. Large energy input on feedstock powders generates several byproducts, including varying amounts of virgin microparticles, nanoparticles, spatter, and volatile chemicals that are emitted in the working environment; throughout the production and processing phases. The micro and nanoscale size may enable particles to interact with and to cross biological barriers, which could, in turn, give rise to unexpected adverse outcomes, including inflammation, oxidative stress, activation of signaling pathways, genotoxicity, and carcinogenicity. Another important aspect of AM-associated risks is emission/leakage of mono- and oligomers due to polymer breakdown and high temperature transformation of chemicals from polymeric particles, both during production, use, and in vivo, including in target cells. These chemicals are potential inducers of direct toxicity, genotoxicity, and endocrine disruption. Nevertheless, understanding whether AM particle powders and their byproducts may exert adverse effects in humans is largely lacking and urges comprehensive safety assessment across the entire AM lifecycle-spanning from virgin and reused to airborne particles. Therefore, this review will detail: 1) brief overview of the AM feedstock powders, impact of reuse on particle physicochemical properties, main exposure pathways and protective measures in AM industry, 2) role of particle biological identity and key toxicological endpoints in the particle safety assessment, and 3) next-generation toxicology approaches in nanosafety for safety assessment in AM. Altogether, the proposed testing approach will enable a deeper understanding of existing and emerging particle and chemical safety challenges and provide a strategy for the development of cutting-edge methodologies for hazard identification and risk assessment in the AM industry.
|
|
| 6. |
- Blanc, Mélanie, 1993-, et al.
(författare)
-
Environmental chemicals differentially affect epigenetic-related mechanisms in the zebrafish liver (ZF-L) cell line and in zebrafish embryos
- 2019
-
Ingår i: Aquatic Toxicology. - : Elsevier. - 0166-445X .- 1879-1514. ; 215
-
Tidskriftsartikel (refereegranskat)abstract
- A number of chemicals have been shown to affect epigenetic patterning and functions. Since epigenetic mechanisms regulate transcriptional networks, epigenetic changes induced by chemical exposure can represent early molecular events for long-term adverse physiological effects. Epigenetics has thus appeared as a research field of major interest within (eco)toxicological sciences. The present study aimed at measuring effects on epigenetic-related mechanisms of selected environmental chemicals (bisphenols, perfluorinated chemicals, methoxychlor, permethrin, vinclozolin and coumarin 47) in zebrafish embryos and liver cells (ZFL). Transcription of genes related to DNA methylation and histone modifications was measured and global DNA methylation was assessed in ZFL cells using the LUMA assay. The differences in results gathered from both models suggest that chemicals affect different mechanisms related to epigenetics in embryos and cells. In zebrafish embryos, exposure to bisphenol A, coumarin 47, methoxychlor and permethrin lead to significant transcriptional changes in epigenetic factors suggesting that they can impact early epigenome reprogramming related to embryonic development. In ZFL cells, significant transcriptional changes were observed upon exposure to all chemicals but coumarin 47; however, only perfluorooctane sulfonate induced significant effects on global DNA methylation. Notably, in contrast to the other tested chemicals, perfluorooctane sulfonate affected only the expression of the histone demethylase kdm5ba. In addition, kdm5ba appeared as a sensitive gene in zebrafish embryos as well. Taken together, the present results suggest a role for kdm5ba in regulating epigenetic patterns in response to chemical exposure, even though mechanisms remain unclear. To confirm these findings, further evidence is required regarding changes in site-specific histone marks and DNA methylation together with their long-term effects on physiological outcomes.
|
|
| 7. |
- Blanc, Mélanie, 1993-
(författare)
-
How can an organism´s life experience affect their descendants? Insights from epigenetic and transgenerational effects of chemical exposure in zebrafish
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Environmental pollution causes approx. 10% of human diseases, and some develop in the progeny because of parental exposure. Effects passed on to subsequent generations may be a consequence of genetic mutations, or of inherited changes in epigenetic patterns. Epigenetics is the study of mitotically or meiotically heritable changes in gene function that cannot be explained by changes in the DNA sequence. Several chemicals have been suggested to induce epigenetic dysregulation leading to multigenerational and transgenerational effects, i.e. effects that can be observed in completely unexposed generations. However, mechanisms underlying the inheritance of epigenetic changes and their implication in phenotypic adversities are complex and not well-understood. The overall aim of this thesis was to study adverse effects and underlying molecular changes in several generations of zebrafish after parental exposure to selected industrial chemicals. To this end, molecular (lipidomic, transcriptomic, epigenomic) and behavioral analyses were performed. Zebrafish is an acknowledged model for vertebrates in toxicology and biomedicine; as such, the findings can be relevant to many organisms including human. The results from this thesis showed that different types of chemicals, polychlorinated biphenyls, polybromodiphenyl ethers, and permethrin, induced transgenerational effects in concentrations relevant to environmental or human exposures. Impact on anxiety and locomotor activity of zebrafish was observed over several generations. Gene expression and epigenetic (DNA methylation) alterations were partly inherited and suggest stable alteration of specific functions such as glutamatergic/GABAergic neurotransmission and synaptic plasticity. Finally, the findings shed light on experimental limitations and research perspectives, which we expect will contribute to the design of future studies on epigenetically inherited effects of any environmental stress.
|
|
| 8. |
- Blanc, Mélanie, 1993-, et al.
(författare)
-
Mixture-specific gene expression in zebrafish (Danio rerio) embryos exposed to perfluorooctane sulfonic acid (PFOS), perfluorohexanoic acid (PFHxA) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB126)
- 2017
-
Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 590-591, s. 249-257
-
Tidskriftsartikel (refereegranskat)abstract
- Perfluorooctane sulfonic acid (PFOS) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB126) are persistent organic pollutants of high concern because of their environmental persistence, bioaccumulation and toxic properties. Besides, the amphiphilic properties of fluorinated compounds such as PFOS and perfluorohexanoic acid (PFHxA) suggest a role in increasing cell membrane permeability and solubilizing chemicals. The present study aimed at investigating whether PFOS and PFHxA are capable of modifying the activation of PCB126 toxicity-related pathways. For this purpose, zebrafish embryos were exposed in semi-static conditions to 7.5 μg/L of PCB126 alone, in the presence of 25 mg/L of PFOS, 15.7 mg/L of PFHxA or in the presence of both PFOS and PFHxA. Quantitative PCR was performed on embryos aged from 24 h post fertilization (hpf) to 96 hpf to investigate expression changes of genes involved in metabolism of xenobiotics (ahr2, cyp1a), oxidative stress (gpx1a, tp53), lipids metabolism (acaa2, osbpl1a), and epigenetic mechanisms (dnmt1, dnmt3ba). Cyp1a and ahr2 expression were significantly induced by the presence of PCB126. However, after 72 and 78 h of exposure, induction of cyp1a expression was significantly lower when embryos were co-exposed to PCB126 + PFOS + PFHxA when compared to PCB126-exposed embryos. Significant upregulation of gpx1a occurred after exposure to PCB126 + PFHxA and to PCB126 + PFOS + PFHxA at 30 and 48 hpf. Besides, embryos appeared more sensitive to PCB126 + PFOS + PFHxA at 78 hpf: acaa2 and osbpl1a were significantly downregulated; dnmt1 was significantly upregulated. While presented as environmentally safe, PFHxA demonstrated that it could affect gene expression patterns in zebrafish embryos when combined to PFOS and PCB126, suggesting that such mixture may increase PCB126 toxicity. This is of particular relevance since PFHxA is persistent and still being ejected into the environment. Moreover, it provides additional information as to the importance to integrate mixture effects of chemicals in risk assessment and biomonitoring frameworks.
|
|
| 9. |
|
|
| 10. |
- Blanc, Mélanie, 1993-, et al.
(författare)
-
Multi- and transgenerational effects following early-life exposure of zebrafish to permethrin and coumarin 47 : Impact on growth, fertility, behavior and lipid metabolism
- 2020
-
Ingår i: Ecotoxicology and Environmental Safety. - : Academic Press. - 0147-6513 .- 1090-2414. ; 205
-
Tidskriftsartikel (refereegranskat)abstract
- Transgenerational effects induced by environmental stressors are a threat to ecosystems and human health. However, there is still limited observation and understanding of the potential of chemicals to influence life outcomes over several generations. In the present study, we investigated the effects of two environmental contaminants, coumarin 47 and permethrin, on exposed zebrafish (FO) and their progeny (F1-F3). Coumarin 47 is commonly found in personal care products and dyes, whereas permethrin is used as a domestic and agricultural pyrethroid insecticide/insect repellent. Zebrafish (F0) were exposed during early development until 28 days post-fertilization and their progeny (F1-F3) were bred unexposed. On one hand, the effects induced by coumarin 47 suggest no multigenerational toxicity. On the other hand, we found that behavior of zebrafish larvae was significantly affected by exposure to permethrin in F1 to F3 generations with some differences depending on the concentration. This suggests persistent alteration of the neural or neuromuscular function. In addition, lipidomic analyses showed that permethrin treatment was partially correlated with lysophosphatidylcholine levels in zebrafish, an important lipid for neurodevelopment. Overall, these results stress out one of the most widely used pyrethroids can trigger long-term, multi- and possibly transgenerational changes in the nervous system of zebrafish. These neurobehavioral changes echo the effects observed under direct exposure to high concentrations of permethrin and therefore call for more research on mechanisms underlying effect inheritance.
|
|
| 11. |
- Blanc, Mélanie, 1993-, et al.
(författare)
-
The insecticide permethrin induces transgenerational behavioral changes linked to transcriptomic and epigenetic alterations in zebrafish (Danio rerio)
- 2021
-
Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 779
-
Tidskriftsartikel (refereegranskat)abstract
- The pyrethroid insecticide permethrin is widely used for agricultural and domestic purposes. Previous data indicated that it acts as a developmental neurotoxicant and can induce transgenerational effects in non-target organisms. However, associated underlying mechanisms remain unclear. The aim of this study was to investigate permethrin-related transgenerational effects in the zebrafish model, and to identify possible molecular mechanisms underlying inheritance. Zebrafish (F0) were exposed to permethrin during early-life (2 h post-fertilization up to 28 days). The F1 and F2 offspring generations were obtained by pairing exposed F0 males and females, and were bred unexposed. Locomotor and anxiety behavior were investigated, together with transcriptomic and epigenomic (DNA methylation) changes in brains. Permethrin exposed F0 fish were hypoactive at adulthood, while males from the F1 and F2 generations showed a specific decrease in anxiety-like behavior. In F0, transcriptomic data showed enrichment in pathways related to glutamatergic synapse activity, which may partly underlie the behavioral effects. In F1 and F2 males, dysregulation of similar pathways was observed, including a subset of differentially methylated regions that were inherited from the F0 to the F2 generation and indicated stable dysregulation of glutamatergic signaling. Altogether, the present results provide novel evidence on the transgenerational neurotoxic effects of permethrin, as well as mechanistic insight: a transient exposure induces persistent transcriptional and DNA methylation changes that may translate into transgenerational alteration of glutamatergic signaling and, thus, into behavioral alterations.
|
|
| 12. |
|
|
| 13. |
- Chavan, Swapnil, et al.
(författare)
-
Predicting Chemical-Induced Liver Toxicity Using High-Content Imaging Phenotypes and Chemical Descriptors : A Random Forest Approach
- 2020
-
Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 33:9, s. 2261-2275
-
Tidskriftsartikel (refereegranskat)abstract
- Hepatotoxicity is a major reason for the withdrawal or discontinuation of drugs from clinical trials. Thus, better tools are needed to filter potential hepatotoxic drugs early in drug discovery. Our study demonstrates utilization of HCI phenotypes, chemical descriptors, and both combined (hybrid) descriptors to construct random forest classifiers (RFCs) for the prediction of hepatotoxicity. HCI data published by Broad Institute provided HCI phenotypes for about 30 000 samples in multiple replicates. Phenotypes belonging to 346 chemicals, which were tested in up to eight replicates, were chosen as a basis for our analysis. We then constructed individual RFC models for HCI phenotypes, chemical descriptors, and hybrid (chemical and HCI) descriptors. The model that was constructed using selective hybrid descriptors showed high predictive performance with 5-fold cross validation (CV) balanced accuracy (BA) at 0.71, whereas within the given applicability domain (AD), independent test set and external test set prediction BAs were equal to 0.61 and 0.60, respectively. The model constructed using chemical descriptors showed a similar predictive performance with a 5-fold CV BA equal to 0.66, a test set prediction BA within the AD equal to 0.56, and an external test set prediction BA within the AD equal to 0.50. In conclusion, the hybrid and chemical descriptor-based models presented here should be considered as a new tool for filtering hepatotoxic molecules during compound prioritization in drug discovery.
|
|
| 14. |
- Delbro, Dick, 1950-, et al.
(författare)
-
The extracellular matrix-degrading protein ADAMTS5 is expressed in the nuclei of urothelial cells in healthy rats
- 2018
-
Ingår i: Scandinavian Journal of Urology. - : Medical Journals Sweden AB. - 2168-1805 .- 2168-1813. ; 52:2, s. 139-142
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of this study was to investigate whether protein expression of the extracellular matrix-degrading protease ADAMTS5 can be demonstrated in the urinary bladder of healthy rats, and, if so, to determine the localization of this enzyme. Materials and methods: The experiments were conducted with eight inbred male Sprague-Dawley rats. Immunohistochemistry was used to investigate the expression of ADAMTS5 in the urinary bladder. Negative controls were established by either excluding the primary antibody or applying the antibody after it had been preabsorbed with its immunogenic peptide. Confocal microscopy was used to visualize the distribution of ADAMTS5 in the urinary bladder tissue. Results: Immunoreactivity for ADAMTS5 was demonstrated in the urothelium and in the detrusor. This expression was localized not only in the cytoplasm, but also in the nuclei. Confocal microscopy corroborated these findings. Conclusion: Expression of ADAMTS5 was demonstrated in the cytoplasm as well as in the nuclei of the urothelium and detrusor cells, suggesting that it may play a role at the transcriptional level.
|
|
| 15. |
- Jacobsen, Annette, et al.
(författare)
-
Reference gene selection for qPCR Is dependent on cell type rather than treatment in colonic and vaginal human epithelial cell lines
- 2014
-
Ingår i: PLOS ONE. - San Fransisco, USA : Punlic Library of Science. - 1932-6203. ; 9:12, s. e115592-
-
Tidskriftsartikel (refereegranskat)abstract
- The ability of commensal bacteria to influence gene expression in host cells under the influence of pathogenic bacteria has previously been demonstrated, however the extent of this interaction is important for understanding how bacteria can be used as probiotics. Real-time quantitative polymerase chain reaction is the most sensitive tool for evaluating relative changes to gene expression levels. However as a result of its sensitivity an appropriate method of normalisation should be used to account for any variation incurred in preparatory experimental procedures. These variations may result from differences in the amount of starting material, quality of extracted RNA, or in the efficiency of the reverse transcriptase or polymerase enzymes. Selection of an endogenous control gene is the preferred method of normalisation, and ideally a proper validation of the gene's appropriateness for the study in question should be performed. In this study we used quantitative polymerase chain reaction data and applied four different algorithms (geNorm, BestKeeper, NormFinder, and comparative ΔCq) to evaluate eleven different genes as to their suitability as endogenous controls for use in studies involving colonic (HT-29) and vaginal (VK2/E6E7) human mucosal epithelial cells treated with probiotic and pathogenic bacteria. We found phosphoglycerate kinase 1 to be most appropriate for HT-29 cells, and ribosomal protein large P0 to be the best choice for VK2/E6E7 cells. We also showed that use of less stable reference genes can lead to less accurate quantification of expression levels of gene of interest (GOI) and also can result in decreased statistical significance for GOI expression levels when compared to control. Additionally, we found the cell type being analysed had greater influence on reference gene selection than the treatment performed. This study provides recommendations for stable endogenous control genes for use in further studies involving colonic and vaginal cell lines after bacterial challenge.
|
|
| 16. |
- Jacobsen, Annette V., et al.
(författare)
-
Effects of perfluorooctane sulfonate on genes controlling hepatic fatty acid metabolism in livers of chicken embryos
- 2018
-
Ingår i: Environmental Science and Pollution Research. - : Springer Berlin/Heidelberg. - 0944-1344 .- 1614-7499. ; 25:23, s. 23074-23081
-
Tidskriftsartikel (refereegranskat)abstract
- Per- and polyfluoroalkyl substances (PFAS) are synthetic surfactants with a wide variety of applications; however, due to their stability, they are particularly resistant to degradation and, as such, are classed as persistent organic pollutants. Perfluorooctane sulfonate (PFOS) is one such PFAS that is still detectable in a range of different environmental settings, despite its use now being regulated in numerous countries. Elevated levels of PFOS have been detected in various avian species, and the impact of this on avian health is of interest when determining acceptable levels of PFOS in the environment. Due to its similarities to naturally occurring fatty acids, PFOS has potential to disrupt a range of biological pathways, particularly those associated with lipid metabolism, and this has been shown in various species. In this study, we have investigated how in ovo exposure to environmentally relevant levels of PFOS affects expression of genes involved in lipid metabolism of developing chicken embryos. We have found a broad suppression of transcription of genes involved in fatty acid oxidation and PPAR-mediated transcription with more significant effects apparent at lower doses of PFOS. These results highlight the need for more research investigating the biological impacts of low levels of PFAS to properly inform environmental policy governing their regulation.
|
|
| 17. |
- Karlsson, Mattias, 1981-, et al.
(författare)
-
Substances released from probiotic Lactobacillus rhamnosus GR-1 potentiate NF-κB activity in Escherichia coli-stimulated urinary bladder cells
- 2012
-
Ingår i: FEMS Immunology and Medical Microbiology. - Hoboken, USA : Wiley-Blackwell. - 0928-8244 .- 1574-695X. ; 66:2, s. 147-156
-
Tidskriftsartikel (refereegranskat)abstract
- Lactobacillus rhamnosus GR-1 is a probiotic bacterium used to maintain urogenital health. The putative mechanism for its probiotic effect is by modulating the host immunity. Urinary tract infections (UTI) are often caused by uropathogenic Escherichia coli that frequently evade or suppress immune responses in the bladder and can target pathways, including nuclear factor-kappaB (NF-κB). We evaluated the role of L. rhamnosus GR-1 on NF-κB activation in E. coli-stimulated bladder cells. Viable L. rhamnosus GR-1 was found to potentiate NF-κB activity in E. coli-stimulated T24 bladder cells, whereas heat-killed lactobacilli demonstrated a marginal increase in NF-κB activity. Surface components released by trypsin- or LiCl treatment, or the resultant heat-killed shaved lactobacilli, had no effect on NF-κB activity. Isolation of released products from L. rhamnosus GR-1 demonstrated that the induction of NF-κB activity was owing to released product(s) with a relatively large native size. Several putative immunomodulatory proteins were identified, namely GroEL, elongation factor Tu and NLP/P60. GroEL and elongation factor Tu have previously been shown to elicit immune responses from human cells. Isolating and using immune-augmenting substances produced by lactobacilli is a novel strategy for the prevention or treatment of UTI caused by immune-evading E. coli.
|
|
| 18. |
|
|
| 19. |
- Khalaf, Hazem, 1981-, et al.
(författare)
-
Antibacterial effects of Lactobacillus and bacteriocin PLNC8 αβ on the periodontal pathogen Porphyromonas gingivalis
- 2016
-
Ingår i: BMC Microbiology. - London, United Kingdom : BioMed Central (BMC). - 1471-2180. ; 16:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The complications in healthcare systems associated with antibiotic-resistant microorganisms have resulted in an intense search for new effective antimicrobials. Attractive substances from which novel antibiotics may be developed are the bacteriocins. These naturally occurring peptides are generally considered to be safe and efficient at eliminating pathogenic bacteria. Among specific keystone pathogens in periodontitis, Porphyromonas gingivalis is considered to be the most important pathogen in the development and progression of chronic inflammatory disease. The aim of the present study was to investigate the antimicrobial effects of different Lactobacillus species and the two-peptide bacteriocin PLNC8 αβ on P. gingivalis.Results: Growth inhibition of P. gingivalis was obtained by viable Lactobacillus and culture media from L. plantarum NC8 and 44048, but not L. brevis 30670. The two-peptide bacteriocin from L. plantarum NC8 (PLNC8 αβ) was found to be efficient against P. gingivalis through binding followed by permeabilization of the membranes, using Surface plasmon resonance analysis and DNA staining with Sytox Green. Liposomal systems were acquired to verify membrane permeabilization by PLNC8 αβ. The antimicrobial activity of PLNC8 αβ was found to be rapid (1 min) and visualized by TEM to cause cellular distortion through detachment of the outer membrane and bacterial lysis.Conclusion: Soluble or immobilized PLNC8 αβ bacteriocins may be used to prevent P. gingivalis colonization and subsequent pathogenicity, and thus supplement the host immune system against invading pathogens associated with periodontitis.
|
|
| 20. |
- Krivospitskaya, Olesya, 1983-, et al.
(författare)
-
A CYP26B1 polymorphism enhances retinoic acid catabolism and may aggravate atherosclerosis
- 2012
-
Ingår i: Molecular Medicine. - New York, USA : The Feinstein Institute for Medical Research. - 1076-1551 .- 1528-3658. ; 18:1, s. 712-718
-
Tidskriftsartikel (refereegranskat)abstract
- All-trans retinoic acid, controlled by CYP26 enzymes, potentially has beneficial effects in atherosclerosis treatment. This study investigates CYP26B1 in atherosclerosis and effects of a genetic polymorphism in CYP26B1 on retinoid catabolism. We found that CYP26B1 mRNA was induced by retinoic acid in human atherosclerotic arteries and CYP26B1 and the macrophage marker CD68 co-localized in human atherosclerotic lesions. In mice, Cyp26B1 mRNA was higher in atherosclerotic than normal arteries. Databases were queried for non-synonymous CYP26B1 SNPs and rs2241057 selected for further studies. Constructs of the CYP26B1 variants were created and used for production of purified proteins and transfection of macrophage-like cells. The minor variant catabolized retinoic acid with significantly higher efficiency, indicating that rs2241057 is functional and suggesting reduced retinoid availability in tissues with the minor variant. rs2241057 was investigated in a Stockholm Coronary Atherosclerosis Risk Factor (SCARF) subgroup. The minor allele was associated with slightly larger lesions as determined by angiography. In summary, this study identifies the first CYP26B1 polymorphism that alters CYP26B1 capacity to metabolize retinoic acid. CYP26B1 was expressed in macrophage-rich areas of human atherosclerotic lesions, induced by retinoic acid and increased in murine atherosclerosis. Taken together, the results indicate that CYP26B1 capacity is genetically regulated and suggest that local CYP26B1 activity may influence atherosclerosis.
|
|
| 21. |
- Nilén, Greta, 1989-, et al.
(författare)
-
A binary, ternary, and quaternary mixture of PFOS, B[a]P, PCB126, and Arsenic alters behavior, gene expression, and lipid content in zebrafish larvae (Danio rerio)
-
Annan publikation (övrigt vetenskapligt/konstnärligt)
|
|
| 22. |
|
|
| 23. |
- Nilén, Greta, 1989-
(författare)
-
Molecular and phenotypical toxicological effects of environmental pollutants and their mixtures : A mechanistic approach
- 2023
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Current environmental risk assessment of polluted sites primarily relies on single compound evaluation. However, in the environment, organisms are often exposed to complex mixtures of pollutants. To further develop risk assessment of polluted sites and evaluate the risks that mixtures pose to humans and wildlife, a mechanistic understanding of mixture toxicity is needed.The overall aim of this thesis was to increase our knowledge of the toxic effects caused by chemical mixtures and to develop new approaches to investigate the molecular mechanisms underlying such effects. To reach this aim, a comprehensive set of methods was applied, considering molecular and phenotypical alterations as well as chemical analyses.The investigations revealed that the acute toxicity caused by mixtures of the pollutants B[a]P, PFOS, PCB126, and Arsenate is mainly predictable by concentration addition. The results also showed some specific sublethal effects of the various mixtures that were not observed for the single components. In addition, each mixture caused very specific patterns of behavioral alterations, gene expression changes, altered lipid content, and altered organ growth. A complex environmental mixture from soil contaminated with PACs caused for instance behavioral alterations in zebrafish, in addition to dysfunction of genes that are critical for eye development.In summary, this thesis contributes to an increased understanding of the mechanistic pathways underlying the mixture toxicity of selected pollutants and environmental samples. In addition, it provides insights for the development of new approaches that may be included in risk assessment, such as image analysis and effect-directed analysis.
|
|
| 24. |
- Ninyio, Nathaniel, 1985-, et al.
(författare)
-
Development and analysis of prospective anti-HIV probiotic vaccines
- 2022
-
Ingår i: 19th Smögen Summer Symposium on Virology. - : Virus- och Pandemifonden – Swedish Society for Virology. ; , s. 40-40
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Major improvements have been made in the treatment and prevention of HIV/AIDS. However, a prophylactic vaccine is still unavailable, and several vaccine-candidate trials yielded less than favourable results. Given that the HIV pandemic has not slowed down significantly, there is an urgent need for the development of an effective vaccine. The HIV-1 Gag protein, a key player in HIV particle assembly, is a suitable antigen for use in HIV vaccine development since antibodies targeting HIV-1 Gag will interfere with the replication of the virus. In our vaccine development strategy, it was important for us to develop a candidate for mucosal administration. This is because the mucosal route is the major site for HIV transmission and early viral replication, which is associated with extensive and rapid depletion of CD4+ T-cells in the Gut-Associated Lymphoid Tissue (GALT). Here, we transformed probiotic strains of Lactobacillus plantarum and Lactobacillus fermentum with the recombinant plasmid vectors pSIP409 and pSIP411 harbouring the HIV-1 GagM gene. Following electroporation, HIV-1 GagM expression was induced in the probiotics using peptide pheromone. Via PCR and sequencing, the presence of GagM was confirmed in the L. plantarum+ pSIP409-GagM and L. fermentum+ pSIP411-GagM clones. Protein expression was induced with peptide pheromone. Then, protein expression was confirmed by western blotting with goat anti-HIV p24 primary antibody and anti-goat secondary antibody. ELISA was also performed to confirm the antigenicity of the HIV-1 Gag antigen and to also quantify the antigen in the two Lactobacilli clones. Our results show that 1.5×109 CFU of L. plantarum+ pSIP409-GagM expressed 125μg of HIV-1 Gag and 1.9×109 CFU of L. fermentum+ pSIP411-GagM clones expressed 125μg of HIV-1 Gag respectively. In vitro digestion with pepsin, pancreatin and bile salts suggested that partial digestion of the probiotic vaccine candidates may occur when administered orally. Taken together, our probiotic HIV-1 vaccine candidates showed good prospects for further immunological analysis via animal trial.
|
|
| 25. |
- Ninyio, Nathaniel, 1985-, et al.
(författare)
-
Stable expression of HIV-1 MPER extended epitope on the surface of the recombinant probiotic bacteria Escherichia Coli Nissle 1917 using CRISPR/Cas9
- 2024
-
Ingår i: Microbial Cell Factories. - : BioMed Central (BMC). - 1475-2859. ; 23:1
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Mucosal vaccines have the potential to induce protective immune responses at the sites of infection. Applying CRISPR/Cas9 editing, we aimed to develop a probiotic-based vaccine candidate expressing the HIV-1 envelope membrane-proximal external region (MPER) on the surface of E. coli Nissle 1917.RESULTS: The HIV-1 MPER epitope was successfully introduced in the porin OmpF of the E. coli Nissle 1917 (EcN-MPER) and the modification was stable over 30 passages of the recombinant bacteria on the DNA and protein level. Furthermore, the introduced epitope was recognized by a human anti-HIV-1 gp41 (2F5) antibody using both live and heat-killed EcN-MPER, and this antigenicity was also retained over 30 passages. Whole-cell dot blot suggested a stronger binding of anti-HIV-1 gp41 (2F5) to heat-killed EcN-MPER than their live counterpart. An outer membrane vesicle (OMV) - rich extract from EcN-MPER culture supernatant was equally antigenic to anti-HIV-1 gp41 antibody which suggests that the MPER antigen could be harboured in EcN-MPER OMVs. Using quantitative ELISA, we determined the amount of MPER produced by the modified EcN to be 14.3 µg/108 cfu.CONCLUSIONS: The CRISPR/Cas9 technology was an effective method for establishment of recombinant EcN-MPER bacteria that was stable over many passages. The developed EcN-MPER clone was devoid of extraneous plasmids and antibiotic resistance genes which eliminates the risk of plasmid transfer to animal hosts, should this clone be used as a vaccine. Also, the EcN-MPER clone was recognised by anti-HIV-1 gp41 (2F5) both as live and heat-killed bacteria making it suitable for pre-clinical evaluation. Expression of OmpF on bacterial surfaces and released OMVs identifies it as a compelling candidate for recombinant epitope modification, enabling surface epitope presentation on both bacteria and OMVs. By applying the methods described in this study, we present a potential platform for cost-effective and rational vaccine antigen expression and administration, offering promising prospects for further research in the field of vaccine development.
|
|
| 26. |
- Romanenko, PA, et al.
(författare)
-
Morphological and Molecular Characterization of the Representative of Brasilonema (Scytonemataceae, Cyanoprokaryota) from the Tropical Greenhouse in Kiev (Ukraine)
- 2020
-
Ingår i: International Journal of Algae. - : Begell House. - 1521-9429 .- 1940-4328. ; 22:2, s. 103-122
-
Tidskriftsartikel (refereegranskat)abstract
- This paper presents morphological and molecular characterizations of the representative of the pantropic genus Brasilonema Fiore et al. first discovered in a European greenhouse. The genus described in 2007, using an integrated approach, is morphologically close to Scytonema Agardh; differing in the filaments forming ascending bundles, rarely occurring false branching, and the color of cells. To date, 12 species of Brasilonema have been described; all of them occur subaerophytically in humid tropical and subtropical regions. For several years in the greenhouse of the N.N. Grishko National Botanical Garden of the NAS of Ukraine, we observed abundant blackish mats with a fleecy surface, formed by falsely branching filaments of heterocytous cyanobacteria lilac, pale purple or gray in color. Cyanobacteria densely covered the vegetative organs of various tropical epiphytic plants from the Orchidaceae and Bromeliaceae families; sometimes inhabiting concrete and wooden substrates in the greenhouse. The morphological features of this newly discovered cyanobacteria were studied both in natural material greenhouse samples and culture. For cultivation, liquid and agarized N-free BG11 medium was used. The specimens from the mats and the cultures had some differences in thalli habitus, coloration and arrangement of filaments, frequency of false branching, trichome appearance, dimensional limits, etc. A comparative analysis of the original data with descriptions of the known Brasilonema species showed that the Kiev population coincides morphologically and ecologically with several species, of which it's closest relative is B. octagenarum Aguiar et al. Phylogenetic analysis of the nucleotide sequence of the gene encoding 16S rRNA confirmed affiliation of the original strains to Brasilonema. Analysis of the nucleotide sequence of the 16S-23S ITS region, as well as the secondary structure of its most informative helices, showed the closest proximity of the Kiev material to B. octagenarum, which in turn is probably a complex of species whose taxonomic separation is possible in the future. Presumably, cyanobacteria have entered into the Kiev greenhouse with tropical plants, brought by Ukrainian botanists from an expedition to Brazil in 1986.
|
|
| 27. |
- Scherbak, Nikolai, 1967-
(författare)
-
Characterization of stress-inducible short-chain dehydrogenases/reductases (SDR) in plants : study of a novel small protein family from Pisum sativum (pea)
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In pea (Pisum sativum), the short-chain alcohol dehydrogenase-like protein (SAD) gene family consists of at least three members (SAD-A, -B, and -C). The SAD genes are transiently expressed in plants after short exposures to ultraviolet-B radiation, which in turn leads to formation of SAD protein in leaf and stem tissue upon prolonged irradiation. SAD gene expression is also seen as a result of wounding stress.The recombinant SAD-C protein (which was the most highly over-expressed isoform in Escherichia coli of the isoforms) was shown to be a tetramer that probably consists of a dimer of dimers and which possesses quinone-reducing capability. The enzyme shows approximately the same NADH- and NADPH-dependent activity with 2,5- and 2,6-dimethylbenzoquinone and menadione as substrates.Western blotting and immunohistochemistry (IHC) shows that the SAD protein is present to a smaller or larger extent in all the different pea tissues examined. Environmental stress such as UV-B radiation clearly increases the content of SAD in leaf and stem tissue but not in roots. This indicates that increased expression of the SAD genes, as a result of UV-B exposure, is limited to the exposed tissue. This is substantiated by the heterologous GUS expression from the pea SAD-C promoter in Arabidopsis during wounding. Only the wound site and the vicinal tissue show transcription from this promoter. In non-stressed tissue (as well as in UV-B-stressed leaves and stem), SAD predominantly occurred in epidermal or sub-epidermal cells as judged by IHC. The protoderm of the pea seed cotyledonary axis contains the most heavily stained cells. This indicates a possible role for the SAD protein in development as well as in protection against environmental stress. Also, discrete staining was obtained in particular cell types of the ovary.To be able to understand the biochemical and physiological role of the SAD enzyme, an in silico modeling study of the SAD protein structure was performed. The simulations of our SAD protein, as well as of related proteins with known crystal structure (3alfa,20beta-hydroxysteroid dehydrogenase and secoisolariciresinol dehydrogenase), allowed us to obtain an energy-minimized structure for the monomeric SAD as well as important data on the cofactor interaction in the active site.Crystallization of recombinant SAD-C has been performed. The needle-like crystals, which diffract to 3.5Å, contain probably eight monomers in the asymmetric unit, presumably containing a pair of tetramers.SAD enhances the reduction rates of quinones with NADH. However, NADH can also accomplish reduction of certain quinones non-enzymatically. Both theoretical calculations and experimental techniques were used to elucidate the structural and electronic pre-requisites for this non-enzymatic quinone reduction.
|
|
| 28. |
|
|
| 29. |
- Scherbak, Nikolai N., 1967-, et al.
(författare)
-
Glimepiride Compared to Liraglutide Increases Plasma Levels of miR-206, miR-182-5p, and miR-766-3p in Type 2 Diabetes Mellitus : A Randomized Controlled Trial
- 2023
-
Ingår i: Diabetes & metabolism journal. - : Korean Diabetes Association. - 2233-6079 .- 2233-6087. ; 47:5, s. 668-681
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Diabetes is a chronic disease with several long-term complications. Several glucose-lowering drugs are used to treat type 2 diabetes mellitus (T2DM), e.g., glimepiride and liraglutide, in which both having different modes of action. Circulating microRNAs (miRNAs) are suggested as potential biomarkers that are associated with the disease development and the effects of the treatment. In the current study we evaluated the effect of glimepiride, liraglutide on the expression of the circulating miRNAs.METHODS: The present study is a post hoc trial from a previously randomized control trial comparing liraglutide versus glimepiride both in combination with metformin in subjects with T2DM, and subclinical heart failure. miRNAs were determined in the subjects' serum samples with next generation sequencing. Expression patterns of the circulating miRNAs were analyzed using bioinformatic univariate and multivariate analyses (clinical trial registration: NCT01425580).RESULTS: Univariate analyses show that treatment with glimepiride altered expression of three miRNAs in patient serum, miR-206, miR-182-5p, and miR-766-3p. Both miR-182-5p and miR-766-3p were also picked up among the top contributing miRNAs with penalized regularised logistic regressions (Lasso). The highest-ranked miRNAs with respect to Lasso coefficients were miR-3960, miR-31-5p, miR-3613-3p, and miR-378a-3p. Liraglutide treatment did not significantly influence levels of circulating miRNAs.CONCLUSION: Present study indicates that glucose-lowering drugs differently affect the expression of circulating miRNAs in serum in individuals with T2DM. More studies are required to investigate possible mechanisms by which glimepiride is affecting the expression of circulating miRNAs.
|
|
| 30. |
- Scherbak, Nikolai, 1967-, et al.
(författare)
-
Production of anti-viral vaccines using probiotic bacteria
- 2022
-
Ingår i: 19th Smögen Symposium on Virology: Abstracts. - : Virus- och Pandemifonden – Swedish Society for Virology. ; , s. 16-16
-
Konferensbidrag (refereegranskat)abstract
- The mucosal surfaces throughout the body are constantly exposed to microorganisms. The mucosal surfaces accommodate a large part of the body’s immune system. For effective vaccination, it is believed that direct immunization on mucosal surfaces will be more effective than the more conventional systemic immunization. Certain probiotic bacteria provide significant adjuvant effects that may be utilized for the desired immune response. Virus-like particles (VLPs) are complexes of viral proteins that without being infectious are efficient in mimicking the natural viral structures. While presenting the patterns of viral antigens, the VLPs have been shown to efficiently interact with dendritic cells and be effective in triggering the B and T-cell immunity. HIV-1 Gag is one of the most highly conserved structural antigens and contains several immunodominant T- and B-cell epitopes. Mosaic Gag protein matches 74% of 9-amino-acid potential epitopes in global Gag sequences thus maximizing the coverage of potential T-cell epitopes for a viral population.The current study aimed to develop probiotic strains of Lactobacillus plantarum NC8 and E. coli Nissle 1917 that produced recombinant mosaic HIV-1 Gag protein as VLPs.For the transient expression of the mosaic HIV-1 Gag protein (GagM), the gene-carrying expression vectors were transformed into the L. plantarum and in probiotic E.coli Nissle 1917. Protein expression of the GagM was shown to lead to the formation of the VLPs of the recombinant HIV-1 Gag proteins. This was confirmed through immunoblotting and transmission electron microscopy (TEM).Our study shows that probiotic lactobacteria can be developed to express HIV-1 Gag VLPs, which may be used for VLP production and potentially for vaccine delivery. Further evaluation of the concept is merited.
|
|
