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Danielli M, Perne L, Jarc Jovičić E, Petan T. Lipid droplets and polyunsaturated fatty acid trafficking: Balancing life and death. Front Cell Dev Biol 2023; 11:1104725. [PMID: 36776554 PMCID: PMC9911892 DOI: 10.3389/fcell.2023.1104725] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/17/2023] [Indexed: 01/28/2023] Open
Abstract
Lipid droplets are fat storage organelles ubiquitously distributed across the eukaryotic kingdom. They have a central role in regulating lipid metabolism and undergo a dynamic turnover of biogenesis and breakdown to meet cellular requirements for fatty acids, including polyunsaturated fatty acids. Polyunsaturated fatty acids esterified in membrane phospholipids define membrane fluidity and can be released by the activity of phospholipases A2 to act as ligands for nuclear receptors or to be metabolized into a wide spectrum of lipid signaling mediators. Polyunsaturated fatty acids in membrane phospholipids are also highly susceptible to lipid peroxidation, which if left uncontrolled leads to ferroptotic cell death. On the one hand, lipid droplets act as antioxidant organelles that control polyunsaturated fatty acid storage in triglycerides in order to reduce membrane lipid peroxidation, preserve organelle function and prevent cell death, including ferroptosis. On the other hand, lipid droplet breakdown fine-tunes the delivery of polyunsaturated fatty acids into metabolic and signaling pathways, but unrestricted lipid droplet breakdown may also lead to the release of lethal levels of polyunsaturated fatty acids. Precise regulation of lipid droplet turnover is thus essential for polyunsaturated fatty acid distribution and cellular homeostasis. In this review, we focus on emerging aspects of lipid droplet-mediated regulation of polyunsaturated fatty acid trafficking, including the management of membrane lipid peroxidation, ferroptosis and lipid mediator signaling.
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Marrone J, Danielli M, Gaspari CI, Capiglioni AM, Marinelli RA. Aquaporin gene transfer for hepatocellular cholestasis. Biochimie 2021; 188:12-15. [PMID: 33811938 DOI: 10.1016/j.biochi.2021.03.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Revised: 03/22/2021] [Accepted: 03/26/2021] [Indexed: 10/21/2022]
Abstract
Bile secretion by hepatocytes is an osmotic process. The output of bile salts and other organic anions (e.g. glutathione), through the bile salt transporter BSEP/ABCB11 and the organic anion transporter MRP2/ABCC2, respectively, are considered to be the major osmotic driving forces for water secretion into bile canaliculi mainly via aquaporin-8 (AQP8) channels. The down-regulated canalicular expression of these key solute transporters and AQP8 would be a primary event in the establishment of hepatocellular cholestasis. Recent studies in animal models of hepatocellular cholestasis show that the hepatic delivery of AdhAQP1, an adenovector encoding for the archetypical water channel human aquaporin-1 (hAQP1), improves bile secretion and restores to normal the elevated serum bile salt levels. AdhAQP1-transduced hepatocytes show that the canalicularly-expressed hAQP1 not only enhances osmotic membrane water permeability but also induces the transport activities of BSEP/ABCB11 and MRP2/ABCC2 by redistribution in canalicular cholesterol-rich microdomains likely through interactions with the cholesterol-binding protein caveolin-1. Thus, the hepatic gene transfer of hAQP1 improves the bile secretory failure in hepatocellular cholestasis by increasing both biliary output and choleretic efficiency of key osmotic solutes, such as, bile salts and glutathione. The study of hepatocyte aquaporins has provided new insights into the mechanisms of bile formation and cholestasis, and may lead to innovative treatments for cholestatic liver diseases.
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Affiliation(s)
- Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - César I Gaspari
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - Alejo M Capiglioni
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - Raúl A Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina.
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Danielli M, Capiglioni AM, Marrone J, Marinelli RA. Further evidence for the involvement of mitochondrial aquaporin-8 in hepatocyte lipid synthesis. Biochimie 2021; 188:16-19. [PMID: 33493534 DOI: 10.1016/j.biochi.2021.01.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 01/15/2021] [Accepted: 01/15/2021] [Indexed: 11/17/2022]
Abstract
We recently provided evidence suggesting that mitochondrial aquaporin-8 (mtAQP8), a channel protein able to conduct H2O2, is involved in the modulation of hepatocyte cholesterogenesis. To expand that study, we cultured human hepatocyte-derived Huh-7 cells in medium with lipoprotein-deficient serum (LPDS) to induce the de novo synthesis of cholesterol and fatty acids. We found that LPDS induced mtAQP8 expression and that AQP8 gene silencing significantly down-regulated the LPDS-induced synthesis of cholesterol and fatty acids as well as the expression of the corresponding key biosynthetic enzymes, 3-hydroxy-3-methylglutaryl-CoA reductase and fatty acid synthase. Our data further support a regulatory role of mtAQP8 in hepatocyte lipid homeostasis.
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Affiliation(s)
- Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - Alejo M Capiglioni
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina
| | - Raúl A Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000, Rosario, Santa Fe, Argentina.
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Danielli M, Marrone J, Capiglioni AM, Marinelli RA. Data of H 2O 2 release from AQP8-knockdown rat hepatocyte mitochondria. Data Brief 2019; 23:103722. [PMID: 31372390 PMCID: PMC6660618 DOI: 10.1016/j.dib.2019.103722] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/23/2019] [Accepted: 01/25/2019] [Indexed: 12/20/2022] Open
Abstract
This article reports experimental data related to the research article entitled "Mitochondrial aquaporin-8 is involved in SREBP-controlled hepatocyte cholesterol biosynthesis" [Danielli et al., 2019]. We present data about hydrogen peroxide (H2O2) release from mitochondria isolated from rat hepatocytes with or without silencing of aquaporin-8 (AQP8) protein expression. The rate of mitochondrial H2O2 release (pmoles/min/mg mitochondrial protein) was found to be decreased by about 50% in AQP8-knockdown mitochondria.
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Affiliation(s)
- Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Santa Fe, Argentina
| | - Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Santa Fe, Argentina
| | - Alejo M Capiglioni
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Santa Fe, Argentina
| | - Raúl A Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Santa Fe, Argentina
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Danielli M, Marrone J, Capiglioni AM, Marinelli RA. Mitochondrial aquaporin-8 is involved in SREBP-controlled hepatocyte cholesterol biosynthesis. Free Radic Biol Med 2019; 131:370-375. [PMID: 30579780 DOI: 10.1016/j.freeradbiomed.2018.12.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 11/20/2018] [Accepted: 12/14/2018] [Indexed: 01/06/2023]
Abstract
Cholesterol, via sterol regulatory element-binding protein (SREBP) transcription factors, activates or represses genes involved in its hepatic biosynthetic pathway, and also modulates the expression of hepatocyte mitochondrial aquaporin-8 (mtAQP8), a channel that can function as peroxiporin by facilitating the transmembrane diffusion of H2O2. Here we tested the hypothesis that mtAQP8 is involved in the SREBP-mediated regulation of hepatocyte cholesterol biosynthesis. Using human hepatocyte-derived Huh-7 cells and primary rat hepatocytes, we found that mtAQP8 knockdown significantly downregulated de novo cholesterol synthesis as well as protein expressions of SREBP-2 and its target gene, a rate-limiting enzyme in cholesterol synthesis 3-Hydroxy-3-Methylglutaryl-CoA Reductase (HMGCR). In contrast, adenovirus-mediated human AQP8 mitochondrial expression significantly increased de novo cholesterol synthesis and protein expressions of SREBP-2 and HMGCR. In mtAQP8-overexpressed hepatocytes, mitochondrial H2O2 release was found to be increased; and a mitochondria-targeted antioxidant prevented the upregulation of mitochondrial H2O2 release and that of cholesterol synthesis. Our results suggest that peroxiporin mtAQP8 plays a role in the SREBP-controlled hepatocyte cholesterogenesis, a finding that might be relevant to cholesterol-related metabolic disorders.
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Affiliation(s)
- Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Alejo M Capiglioni
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Raúl A Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina.
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Marrone J, Danielli M, Gaspari CI, Marinelli RA. Adenovirus-mediated human aquaporin-1 expression in hepatocytes improves lipopolysaccharide-induced cholestasis. IUBMB Life 2017; 69:978-984. [DOI: 10.1002/iub.1689] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/01/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario; Santa Fe Argentina
| | - Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario; Santa Fe Argentina
| | - César I. Gaspari
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario; Santa Fe Argentina
| | - Raúl A. Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario; Santa Fe Argentina
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Danielli M, Capiglioni AM, Marrone J, Calamita G, Marinelli RA. Cholesterol can modulate mitochondrial aquaporin-8 expression in human hepatic cells. IUBMB Life 2017; 69:341-346. [DOI: 10.1002/iub.1615] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 02/15/2017] [Indexed: 12/21/2022]
Affiliation(s)
- Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Rosario Argentina
| | - Alejo M. Capiglioni
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Rosario Argentina
| | - Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Rosario Argentina
| | - Giuseppe Calamita
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica; Università degli Studi di Bari “Aldo Moro,”; Bari Italy
| | - Raúl A. Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas; Universidad Nacional de Rosario; Rosario Argentina
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Marrone J, Soria LR, Danielli M, Lehmann GL, Larocca MC, Marinelli RA. Hepatic gene transfer of human aquaporin-1 improves bile salt secretory failure in rats with estrogen-induced cholestasis. Hepatology 2016; 64:535-48. [PMID: 26999313 DOI: 10.1002/hep.28564] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 02/24/2016] [Accepted: 03/10/2016] [Indexed: 12/15/2022]
Abstract
UNLABELLED The adenoviral gene transfer of human aquaporin-1 (hAQP1) water channels to the liver of 17α-ethinylestradiol-induced cholestatic rats improves bile flow, in part by enhancing canalicular hAQP1-mediated osmotic water secretion. To gain insight into the mechanisms of 17α-ethinylestradiol cholestasis improvement, we studied the biliary output of bile salts (BS) and the functional expression of the canalicular BS export pump (BSEP; ABCB11). Adenovector encoding hAQP1 (AdhAQP1) or control vector was administered by retrograde intrabiliary infusion. AdhAQP1-transduced cholestatic rats increased the biliary output of major endogenous BS (50%-80%, P < 0.05) as well as that of taurocholate administered in choleretic or trace radiolabel amounts (around 60%, P < 0.05). Moreover, liver transduction with AdhAQP1 normalized serum BS levels, otherwise markedly elevated in cholestatic animals. AdhAQP1 treatment was unable to improve BSEP protein expression in cholestasis; however, its transport activity, assessed by adenosine triphosphate-dependent taurocholate transport in canalicular membrane vesicles, was induced by 90% (P < 0.05). AdhAQP1 administration in noncholestatic rats induced no significant changes in either biliary BS output or BSEP activity. Canalicular BSEP, mostly present in raft (high cholesterol) microdomains in control rats, was largely found in nonraft (low cholesterol) microdomains in cholestasis. Considering that BSEP activity directly depends on canalicular membrane cholesterol content, decreased BSEP presence in rafts may contribute to BSEP activity decline in 17α-ethinylestradiol cholestasis. In AdhAQP1-transduced cholestatic rats, BSEP showed a canalicular microdomain distribution similar to that of control rats, which provides an explanation for the improved BSEP activity. CONCLUSION Hepatocyte canalicular expression of hAQP1 through adenoviral gene transfer promotes biliary BS output by modulating BSEP activity in estrogen-induced cholestasis, a novel finding that might help us to better understand and treat cholestatic disorders. (Hepatology 2016;64:535-548).
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Affiliation(s)
- Julieta Marrone
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Leandro R Soria
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Guillermo L Lehmann
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Maria Cecilia Larocca
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Raúl A Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
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Danielli M, Marinelli RA. Lipid-based transfection reagents can interfere with cholesterol biosynthesis. Anal Biochem 2015; 495:1-2. [PMID: 26656923 DOI: 10.1016/j.ab.2015.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 11/06/2015] [Accepted: 11/09/2015] [Indexed: 10/22/2022]
Abstract
Lipid-based transfection reagents are widely used for delivery of small interfering RNA into cells. We examined whether the commonly used commercial transfection reagents DharmaFECT-4 and Lipofectamine 2000 can interfere with lipid metabolism by studying cholesterogenesis. Cholesterol de novo synthesis from [(14)C]acetate was assessed in human hepatocyte-derived Huh-7 cells. The results revealed that DharmaFECT, but not Lipofectamine, markedly inhibited cholesterol biosynthesis by approximately 70%. Cell viability was not significantly altered. These findings suggest that caution is required in the choice of certain lipid-based transfection reagents for gene silencing experiments, particularly when assessing cholesterol metabolism.
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Affiliation(s)
- Mauro Danielli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000 Rosario, Argentina.
| | - Raúl A Marinelli
- Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, 2000 Rosario, Argentina.
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Molinas SM, Soria LR, Marrone J, Danielli M, Trumper L, Marinelli RA. Acidosis-induced downregulation of hepatocyte mitochondrial aquaporin-8 and ureagenesis from ammonia. Biochem Cell Biol 2015; 93:417-20. [PMID: 26194146 DOI: 10.1139/bcb-2014-0168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It has been proposed that, during metabolic acidosis, the liver downregulates mitochondrial ammonia detoxification via ureagenesis, a bicarbonate-consuming process. Since we previously demonstrated that hepatocyte mitochondrial aquaporin-8 channels (mtAQP8) facilitate the uptake of ammonia and its metabolism into urea, we studied whether mtAQP8 is involved in the liver adaptive response to acidosis. Primary cultured rat hepatocytes were adapted to acidosis by exposing them to culture medium at pH 7.0 for 40 h. Control cells were exposed to pH 7.4. Hepatocytes exposed to acid medium showed a decrease in mtAQP8 protein expression (-30%, p < 0.05). Ureagenesis from ammonia was assessed by incubating the cells with (15)N-labeled ammonia and measuring (15)N-labeled urea synthesis by nuclear magnetic resonance. Reduced ureagenesis was found in acidified hepatocytes (-31%, p < 0.05). In vivo studies in rats subjected to 7 days acidosis also showed decreased protein expression of hepatic mtAQP8 (-50%, p < 0.05) and reduced liver urea content (-35%; p < 0.05). In conclusion, our in vitro and in vivo data suggest that hepatic mtAQP8 expression is downregulated in acidosis, a mechanism that may contribute to decreased ureagenesis from ammonia in response to acidosis.
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Affiliation(s)
- Sara M Molinas
- a Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, (2000) Rosario, Argentina.,b Farmacología. Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, (2000) Rosario, Argentina
| | - Leandro R Soria
- a Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, (2000) Rosario, Argentina
| | - Julieta Marrone
- a Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, (2000) Rosario, Argentina
| | - Mauro Danielli
- a Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, (2000) Rosario, Argentina
| | - Laura Trumper
- b Farmacología. Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, (2000) Rosario, Argentina.,c Consejo de Investigaciones de la Universidad Nacional de Rosario (CIUNR)
| | - Raúl A Marinelli
- a Instituto de Fisiología Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, (2000) Rosario, Argentina
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Danielli JF, Danielli M, Fraser JB, Mitchell PD, Owen LN, Shaw G. BAL-INTRAV: a new non-toxic thiol for intravenous injection in arsenical poisoning: 1. Biological observations. 2. Chemical observations. Biochem J 1947; 41:325-33. [PMID: 16748167 PMCID: PMC1258485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Affiliation(s)
- J F Danielli
- The Biochemical Laboratory, Cambridge, and the Department of Organic Chemistry, Imperial College of Science and Technology, London, S.W. 7
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