| 1. |
- Klionsky, Daniel J., et al.
(författare)
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Guidelines for the use and interpretation of assays for monitoring autophagy
- 2012
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Ingår i: Autophagy. - : Informa UK Limited. - 1554-8635 .- 1554-8627. ; 8:4, s. 445-544
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Forskningsöversikt (refereegranskat)abstract
- In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field.
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| 2. |
- Hu, Y., et al.
(författare)
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Antagonistic Effects of a Mixture of Low-Dose Nonylphenol and Di-N-Butyl Phthalate (Monobutyl Phthalate) on the Sertoli Cells and Serum Reproductive Hormones in Prepubertal Male Rats In Vitro and In Vivo
- 2014
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Ingår i: Plos One. - : Public Library of Science (PLoS). - 1932-6203. ; 9:3
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Tidskriftsartikel (refereegranskat)abstract
- The estrogenic chemical nonylphenol (NP) and the antiandrogenic agent di-n-butyl phthalate (DBP) are regarded as widespread environmental endocrine disruptors (EDCs) which at high doses in some species of laboratory animals, such as mice and rats, have adverse effects on male reproduction and development. Given the ubiquitous coexistence of various classes of EDCs in the environment, their combined effects warrant clarification. In this study, we attempted to determine the mixture effects of NP and DBP on the testicular Sertoli cells and reproductive endocrine hormones in serum in male rats based on quantitative data analysis by a mathematical model. In the in vitro experiment, monobutyl phthalate (MBP), the active metabolite of DBP, was used instead of DBP. Sertoli cells were isolated from 9-day-old Sprague-Dawley rats followed by treatment with NP and MBP, singly or combined. Cell viability, apoptosis, necrosis, membrane integrity and inhibin-B concentration were tested. In the in vivo experiment, rats were gavaged on postnatal days 23-35 with a single or combined NP and DBP treatment. Serum reproductive hormone levels were recorded. Next, Bliss Independence model was employed to analyze the quantitative data obtained from the in vitro and in vivo investigation. Antagonism was identified as the mixture effects of NP and DBP (MBP). In this study, we demonstrate the potential of Bliss Independence model for the prediction of interactions between estrogenic and antiandrogenic agents.
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| 3. |
- Hu, Y., et al.
(författare)
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Mixture effects of nonylphenol and di-n-butyl phthalate (monobutyl phthalate) on the tight junctions between Sertoli cells in male rats in vitro and in vivo
- 2014
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Ingår i: Experimental and Toxicologic Pathology. - : Elsevier BV. - 0940-2993. ; 66:9-10, s. 445-454
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Tidskriftsartikel (refereegranskat)abstract
- The estrogenic chemical nonylphenol (NP) and the antiandrogenic agent di-n-butyl phthalate (DBP) are regarded as widespread environmental endocrine disruptors (EEDs) which at high doses in some species of laboratory animals have adverse effects on male reproduction and development. Given the ubiquitous coexistence of various classes of EEDs in the environment, their combined effects warrant investigation. In this study, we attempted to clarify the interactions of NP and DBP on tight junctions (TJs) between rat Sertoli cells. In the in vitro experiment, monobutyl phthalate (MBP), the active metabolite of DBP, was used instead of DBP. Sertoli cells were isolated from Sprague-Dawley rats, and treated with NP and MBP, singly or combined. The morphology of Sertoli cells, and structure and functionality of TJs were measured. In the in vivo experiment, rats were gavaged on postnatal day 23-35 with a single or combined NP and DBP treatment. Testicular weight and morphology of TJs were recorded. These data indicated that NP and DBP/MBP, either in single or in combination, induced the structural and function changes of Sertoli cell tight junctions, both in vivo and in vitro. The combined effect on the regulation of TJ proteins at both the protein and gene levels was correlated to the effect exerted by NP, suggesting that the structure and function of Sertoli cells were more sensitive to exposure to NP than MBP. (C) 2014 Elsevier GmbH. All rights reserved.
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| 4. |
- Wang, Cong, et al.
(författare)
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Inhibition of Wnt/beta-catenin signaling promotes epithelial differentiation of mesenchymal stem cells and repairs bleomycin-induced lung injury
- 2014
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Ingår i: American Journal of Physiology-Cell Physiology. - : American Physiological Society. - 0363-6143 .- 1522-1563. ; 307:3
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Tidskriftsartikel (refereegranskat)abstract
- Idiopathic pulmonary fibrosis is a progressive lung disorder of unknown etiology. Previous studies have shown that aberrant activation of the Wnt/beta-catenin signaling cascade occurs in lungs of patients with idiopathic pulmonary fibrosis. Given the important roles of the Wnt/beta-catenin signaling pathway in the development of pulmonary fibrosis, we targeted this pathway for the intervention of pulmonary fibrosis with XAV939, a small molecule that specifically inhibits Tankyrase 1/2, eventually leading to the degradation of beta-catenin and suppression of the Wnt/beta-catenin signaling pathway. Our results demonstrated that XAV939 significantly inhibited the activation of Wnt/beta-catenin signaling and attenuated bleomycin-induced lung fibrosis in mice, and thus improved the survival of mice with lung injury. Interestingly, previous investigations have confirmed that endogenous and exogenous mesenchymal stem cells could be recruited to the injured lung, although the exact effects of these cells are debatable. To determine the effect of Wnt/beta-catenin signaling in the epithelial differentiation of bone marrow-derived mesenchymal stem cells (BM-MSCs), we established a coculture system that contains BM-MSCs and alveolar type II epithelial cells. The in vitro experiments demonstrated that XAV939 could promote the differentiation of BM-MSCs into an epithelium-like phenotype in the coculture system. We also found that XAV939 could inhibit the proliferation and myofibroblast differentiation of NIH/3T3 fibroblasts. This work supports that inhibition of the Wnt/beta-catenin signaling pathway may be exploited for the treatment of idiopathic pulmonary fibrosis for which effective treatment strategies are still lacking.
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