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Prophylactic supplementation with selenium alters disposition of mercury in aged rats. Exp Gerontol 2021; 149:111289. [PMID: 33741456 DOI: 10.1016/j.exger.2021.111289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 02/09/2021] [Accepted: 02/19/2021] [Indexed: 11/23/2022]
Abstract
Mercury (Hg) is a prevalent environmental toxicant to which older individuals are particularly susceptible. Selenium (Se) has been used as an antidote following exposure to Hg. However, little is known about the effect of prophylactic supplementation with Se on the handling of Hg. The current study was designed to test the hypothesis that oral pre-treatment with Se alters the corporal disposition of Hg and reduces the risk of Hg-induced toxicity. Young and aged rats were gavaged for 10 days with sodium selenite or saline. On day 11, rats were injected intravenously with 0.5 μmol HgCl2·kg-1·2 mL-1 normal saline. After 24 h, rats were euthanized and organs and tissues were harvested for determination of Hg content. Accumulation of Hg in the kidney was reduced significantly by pre-treatment with Se in both young and aged rats. In the renal cortex, the magnitude of the reduction was greater in aged rats than in young rats but in the outer stripe of the outer medulla, the magnitude of the reduction was similar between groups of rats. Urinary excretion of Hg was also reduced in rats pre-treated with Se. In contrast, the hepatic and hematologic burden of Hg increased in rats pre-treated with Se. Fecal excretion of Hg was decreased significantly by pre-treatment with Se in young rats but not in aged rats. These data suggest that prophylactic supplementation with Se alters the corporal disposition of Hg in a way that may reduce Hg-induced toxicity in target organs.
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Orr SE, George HS, Barnes MC, Mathis TN, Joshee L, Barkin J, Kiefer AM, Seney CS, Bridges CC. Co-administration of Selenium with Inorganic Mercury Alters the Disposition of Mercuric Ions in Rats. Biol Trace Elem Res 2020; 195:187-195. [PMID: 31332705 DOI: 10.1007/s12011-019-01835-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/11/2019] [Indexed: 12/11/2022]
Abstract
Mercury (Hg) is a common environmental toxicant to which humans are exposed regularly through occupational and dietary means. Although selenium supplementation has been reported to prevent the toxic effects of Hg in animals, the mechanisms for this prevention are not well understood. The purpose of the current study was to determine the effects of selenium on the disposition and toxicity of Hg. Wistar rats were injected intravenously with a non-nephrotoxic dose (0.5 μmol kg-1) or a nephrotoxic dose (2.5 μmol kg-1) of HgCl2 (containing radioactive Hg) with or without co-administration of sodium selenite (Na2SeO3). Twenty-four hours after exposure, rats were euthanized, and organs were harvested. Co-administration of SeO32- with HgCl2 reduced the renal burden of Hg and the urinary excretion of Hg while increasing the amount of Hg in blood and spleen. We propose that Hg reacts with reduced selenite in the blood to form large Hg-Se complexes that are unable to be filtered at the glomerulus. Consequently, these complexes remain in the blood and are able to accumulate in blood-rich organs. These complexes, which may have fewer toxic effects than other species of Hg, may be eliminated slowly over the course of weeks to months.
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Affiliation(s)
- Sarah E Orr
- Department of Biomedical Sciences, Mercer University School of Medicine, 1501 Mercer University Dr, Macon, GA, 31207, USA
| | - Hannah S George
- Department of Biomedical Sciences, Mercer University School of Medicine, 1501 Mercer University Dr, Macon, GA, 31207, USA
| | - Mary C Barnes
- Department of Biomedical Sciences, Mercer University School of Medicine, 1501 Mercer University Dr, Macon, GA, 31207, USA
| | - Taylor N Mathis
- Department of Biomedical Sciences, Mercer University School of Medicine, 1501 Mercer University Dr, Macon, GA, 31207, USA
| | - Lucy Joshee
- Department of Biomedical Sciences, Mercer University School of Medicine, 1501 Mercer University Dr, Macon, GA, 31207, USA
| | - Jennifer Barkin
- Department of Community Medicine, Mercer University School of Medicine, Macon, GA, USA
| | - Adam M Kiefer
- Department of Chemistry, Mercer University, Macon, GA, USA
| | - Caryn S Seney
- Department of Chemistry, Mercer University, Macon, GA, USA
| | - Christy C Bridges
- Department of Biomedical Sciences, Mercer University School of Medicine, 1501 Mercer University Dr, Macon, GA, 31207, USA.
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Qiao X, Li Y, Mai J, Ji X, Li Q. Effect of Dibutyltin Dilaurate on Triglyceride Metabolism through the Inhibition of the mTOR Pathway in Human HL7702 Liver Cells. Molecules 2018; 23:E1654. [PMID: 29986449 PMCID: PMC6099942 DOI: 10.3390/molecules23071654] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Revised: 06/26/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022] Open
Abstract
Dibutyltin dilaurate (DBTD) has multiple applications in daily life. However, DBTD is easily deposited in the liver and affects liver functions. This study was designed to explore the effects of DBTD on triglyceride metabolism in human normal hepatocyte HL7702 cells. Our results showed that the intracellular fat contents were dose-dependently decreased by DBTD. The expression of lipolysis genes and proteins were elevated while the lipogenesis genes and proteins were diminished by DBTD. The phosphorylation levels of ribosomal S6 kinase 1 were reduced by both rapamycin and DBTD, indicating that the mTOR pathway was suppressed possibly. The decreased sterol regulatory element-binding protein 1C (SREBP1C) transcription levels, as well as the increased peroxisome proliferator-activated receptor alpha (PPARα) transcription levels, caused by rapamycin and DBTD corresponded to the inactive mTOR pathway. In conclusion, it was possible that DBTD reduced the intracellular triglyceride through depressing the mTOR pathway and affecting its downstream transcription factors.
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Affiliation(s)
- Xiaozhi Qiao
- School of Pharmaceutical Science, Shanxi Medical University, Taiyuan 030001, China.
| | - Yunlan Li
- School of Pharmaceutical Science, Shanxi Medical University, Taiyuan 030001, China.
- Department of Traditional Chinese Medicine, Shanxi University of Traditional Chinese Medicine, Jinzhong 030619, China.
| | - Jiaqi Mai
- School of Pharmaceutical Science, Shanxi Medical University, Taiyuan 030001, China.
| | - Xiaoqing Ji
- School of Pharmaceutical Science, Shanxi Medical University, Taiyuan 030001, China.
| | - Qingshan Li
- School of Pharmaceutical Science, Shanxi Medical University, Taiyuan 030001, China.
- Department of Traditional Chinese Medicine, Shanxi University of Traditional Chinese Medicine, Jinzhong 030619, China.
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Merkord J, Görl N, Lemke M, Berg A, Weber H, Ramer R, Hennighausen G. Influence of daily oral prophylactic selenium treatment on the dibutyltin dichloride (DBTC)-induced pancreatitis in rats. EXCLI JOURNAL 2017; 16:89-100. [PMID: 28435430 PMCID: PMC5379116 DOI: 10.17179/excli2016-466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 01/02/2017] [Indexed: 12/26/2022]
Abstract
Dibutyltin dichloride (DBTC) is an organotin compound used as model for acute and chronic pancreatitis. Oxidative stress is one of the mechanisms of propagation of acinar cell injury in acute pancreatitis. Selenium is an essential cofactor in the antioxidant glutathione peroxidase pathway. Selenium levels are described to be subnormal in patients with acute and chronic pancreatitis. The aim of our studies was to determine the prophylactic effect of Na-selenite [5 mg kg-1 body weight (b.w.) per os (p.o.) 7 days] on the pathogenesis and course of DBTC- induced pancreatitis. Male inbred rats (LEW-1W Charles River) of 150 g body weight were used in this study. Experimental pancreatitis was induced by intravenous administration of 6 mg kg-1 b.w. DBTC in rats. Na-selenite was administered as daily oral dose of 5 mg kg-1 b.w. 7 days before induction of DBTC-pancreatitis. Malondialdehyde (MDA) was measured for monitoring levels of oxidative stress. Elimination of DBTC was reflected as tin concentration in bile and urine. Organ changes were indicated by serum parameters as well as histology. A prophylactic Na-selenite application significantly diminished MDA- and bilirubin concentration in serum, activities of lipase and transaminases as well as organ injuries compared to DBTC- treated rats in the absence of Na-selenite. The prophylactic oral treatment with Na-selenite in the scope of DBTC-induced pancreatitis points to a reduced oxidative stress characterized by diminished MDA serum levels and a milder course of pancreatitis suggesting prophylactic substitution with Na-selenite to probably elicit beneficial effect on the clinical outcome in patients with endoscopic retrograde cholangiopancreatography (ERCP).
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Affiliation(s)
- J Merkord
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, Rostock
| | - N Görl
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, Rostock
| | - M Lemke
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, Rostock
| | - A Berg
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, Rostock
| | - H Weber
- Institute of Clinical Chemistry and Pathobiochemistry, Rostock University Medical Center, Rostock
| | - R Ramer
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, Rostock
| | - G Hennighausen
- Institute of Pharmacology and Toxicology, Rostock University Medical Center, Rostock
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Yang L, Shen J, He S, Hu G, Shen J, Wang F, Xu L, Dai W, Xiong J, Ni J, Guo C, Wan R, Wang X. L-cysteine administration attenuates pancreatic fibrosis induced by TNBS in rats by inhibiting the activation of pancreatic stellate cell. PLoS One 2012; 7:e31807. [PMID: 22359633 PMCID: PMC3281011 DOI: 10.1371/journal.pone.0031807] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 01/16/2012] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND AIMS Recent studies have shown that activated pancreatic stellate cells (PSCs) play a major role in pancreatic fibrogenesis. We aimed to study the effect of L-cysteine administration on fibrosis in chronic pancreatitis (CP) induced by trinitrobenzene sulfonic acid (TNBS) in rats and on the function of cultured PSCs. METHODS CP was induced by TNBS infusion into rat pancreatic ducts. L-cysteine was administrated for the duration of the experiment. Histological analysis and the contents of hydroxyproline were used to evaluate pancreatic damage and fibrosis. Immunohistochemical analysis of α-SMA in the pancreas was performed to detect the activation of PSCs in vivo. The collagen deposition related proteins and cytokines were determined by western blot analysis. DNA synthesis of cultured PSCs was evaluated by BrdU incorporation. We also evaluated the effect of L-cysteine on the cell cycle and cell activation by flow cytometry and immunocytochemistry. The expression of PDGFRβ, TGFβRII, collagen 1α1 and α-SMA of PSCs treated with different concentrations of L-cysteine was determined by western blot. Parameters of oxidant stress were evaluated in vitro and in vivo. Nrf2, NQO1, HO-1, IL-1β expression were evaluated in pancreas tissues by qRT-PCR. RESULTS The inhibition of pancreatic fibrosis by L-cysteine was confirmed by histological observation and hydroxyproline assay. α-SMA, TIMP1, IL-1β and TGF-β1 production decreased compared with the untreated group along with an increase in MMP2 production. L-cysteine suppressed the proliferation and extracellular matrix production of PSCs through down-regulating of PDGFRβ and TGFβRII. Concentrations of MDA+4-HNE were decreased by L-cysteine administration along with an increase in GSH levels both in tissues and cells. In addition, L-cysteine increased the mRNA expression of Nrf2, NQO1 and HO-1 and reduced the expression of IL-1β in L-cysteine treated group when compared with control group. CONCLUSION L-cysteine treatment attenuated pancreatic fibrosis in chronic pancreatitis in rats.
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Affiliation(s)
- LiJuan Yang
- Department of Gastroenterology, The First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - JiaQing Shen
- Department of Gastroenterology, The First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - ShanShan He
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - GuoYong Hu
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - Jie Shen
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - Feng Wang
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - Ling Xu
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - WeiQi Dai
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - Jie Xiong
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - JianBo Ni
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - ChuanYong Guo
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - Rong Wan
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
| | - XingPeng Wang
- Department of Gastroenterology, The First People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
- Department of Gastroenterology, The Tenth People's Hospital of Shanghai, Tongji University, Shanghai, People's Republic of China
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Comparison of antioxidative and antifibrotic effects of α-tocopherol with those of tocotrienol-rich fraction in a rat model of chronic pancreatitis. Pancreas 2011; 40:1091-6. [PMID: 21926544 DOI: 10.1097/mpa.0b013e31821b59c6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES The α-tocopherol and tocotrienol-rich fraction (TRF) are considered effective antioxidants. This study aimed to compare the antioxidative and antifibrotic effects of α-tocopherol and TFR in dibutylin dichloride (DBTC)-induced chronic pancreatitis (CP) rats. METHODS Oral administration of α-tocopherol and TFR (both 800 mg/kg per day) started the next day after DBTC (8 mg/kg) infusion into the tail vein for 4 weeks. Histological examination, Sirius red staining, and measurement of the contents of hydroxyproline and malondialdehyde of the pancreas were performed to evaluate pancreatic damage and fibrosis. Immunohistochemical analysis of α-smooth muscle actin and real-time reverse transcription polymerase chain reaction for transforming growth factor-β1 (TGF-β1) and collagen-α1(I) were performed to evaluate the activation of pancreatic stellate cells and the mRNA levels of fibrosis-related genes, respectively. RESULTS Both α-tocopherol and TRF reduced oxidative stress, ameliorated inflammation and fibrosis, and down-regulated the mRNA expression of TGF-β1 and collagen-α1(I) in DBTC-induced CP. The TRF was superior to α-tocopherol in alleviating inflammation and fibrosis and down-regulating TGF-β1 mRNA expression. CONCLUSIONS Oral administration of α-tocopherol and TRF improves pancreatic inflammation and fibrosis in DBTC-induced CP rats, with TRF being more effective than α-tocopherol. Therefore, TRF may be a novel option for alleviating inflammation and, particularly, the fibrotic process in CP.
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Abstract
Reactive oxygen and reactive nitrogen species (ROS/RNS) have been implicated in the pathogenesis of acute and chronic pancreatitis. Clinical and basic science studies have indicated that ROS/RNS formation processes are intimately linked to the development of the inflammatory disorders. The detrimental effects of highly reactive ROS/RNS are mediated by their direct actions on biomolecules (lipids, proteins, and nucleic acids) and activation of proinflammatory signal cascades, which subsequently lead to activation of immune responses. The present article summarizes the possible sources of ROS/RNS formation and the detailed signaling cascades implicated in the pathogenesis of pancreatic inflammation, as observed in acute and chronic pancreatitis. A therapeutic ROS/RNS-scavenging strategy has been advocated for decades; however, clinical studies examining such approaches have been inconsistent in their results. Emerging evidence indicates that pancreatitis-inducing ROS/RNS generation may be attenuated by targeting ROS/RNS-generating enzymes and upstream mediators.
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Affiliation(s)
- Po Sing Leung
- Department of Physiology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
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