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Li W, Li H, Hu Q, Wang L, Yin Z, Hu G. IGFBP1a is a nutrient deficient response factor that can inhibit fish reproduction through the hypothalamus-pituitary-ovary axis†. Biol Reprod 2024; 110:761-771. [PMID: 38374691 DOI: 10.1093/biolre/ioae009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/27/2023] [Accepted: 01/09/2024] [Indexed: 02/21/2024] Open
Abstract
Reproduction is a high energy consuming process, so long-term malnutrition can significantly inhibit gonadal development. However, little is known about the molecular mechanism by which fasting inhibits reproduction. Our present study found that fasting could dramatically induce insulin-like growth factor binding protein 1 (IGFBP1) expression in the liver, hypothalamus, pituitary and ovaries of grass carp. In addition, IGFBP1a in the hypothalamus-pituitary-gonad axis could inhibit the development of gonads. These results indicated that fasting may participate in the regulation of fish gonadal development through the mediation of IGFBP1a. Further studies found that IGFBP1a could markedly inhibit gonadotropin-releasing hormone 3 expressions in hypothalamus cells. At the pituitary level, IGFBP1a could significantly reduce the gonadotropin hormones (LH and FSH) expression by blocking the action of pituitary insulin-like growth factor 1. Interestingly, IGFBP1a could also directly inhibit the expression of lhr, fshr, and sex steroid hormone synthase genes (cyp11a, cyp17a, and cyp19a1) in the ovary. These results indicated that IGFBP1a should be a nutrient deficient response factor that could inhibit fish reproduction through the hypothalamus-pituitary-ovary axis.
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Affiliation(s)
- Wei Li
- Hubei Hongshan Laboratory, College of Fisheries, Huazhong Agricultural University, Wuhan, China
| | - Hangyu Li
- Hubei Hongshan Laboratory, College of Fisheries, Huazhong Agricultural University, Wuhan, China
| | - Qiongyao Hu
- Hubei Hongshan Laboratory, College of Fisheries, Huazhong Agricultural University, Wuhan, China
| | - Linlin Wang
- Hubei Hongshan Laboratory, College of Fisheries, Huazhong Agricultural University, Wuhan, China
| | - Zhan Yin
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Guangfu Hu
- Hubei Hongshan Laboratory, College of Fisheries, Huazhong Agricultural University, Wuhan, China
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Kondaparthi P, Deore M, Naqvi S, Flora SJS. Dose-dependent hepatic toxicity and oxidative stress on exposure to nano and bulk selenium in mice. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:53034-53044. [PMID: 34023997 DOI: 10.1007/s11356-021-14400-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 05/10/2021] [Indexed: 06/12/2023]
Abstract
Selenium is an essential mineral naturally found in soil, water, and some of the food and is required as essential elements in human and animal body. Se supplementation is required especially for those having Se deficiency. Food supplement of selenium has several forms such as selenocysteine, selenite, selenomethionine, and selenate. Recently, Se supplement as selenium nanoparticles (SeNPs) has gained worldwide attention due to its bioactivities and properties. In the present study, we determined the potential hepatotoxicity of nano and bulk selenium using low and high doses in mice. Twenty-five Swiss albino mice (n=5) were randomly divided into 5 groups and treated orally for 28 days: Group 1: sterile saline (0.9%) as a control; Group 2: sodium selenite (1mg/kg); Group 3: sodium selenite (4mg/kg); Group 4: selenium nanoparticles (1mg/kg); and Group 5: selenium nanoparticles (4mg/kg). Administration of nano-selenium (70-90 nm) led to an increase in the activities of serum transaminases (ALT and AST), while no significant effects were noted on biochemical variables indicative of changes in heme synthesis pathway and oxidative stress like blood δ-aminolevulinic acid dehydratase (δ-ALAD), hepatic reactive oxygen species (ROS), catalase activity, superoxide dismutase (SOD), malondialdehyde assay (MDA), reduced glutathione (GSH) and oxidized glutathione (GSSG), glutathione peroxidase (GPx) compared to controls, and a high dose of sodium selenite. Our results suggest that nano-selenium at low dose (1mg/kg) exhibited antioxidant effects in the liver compared to the high dose (4mg/kg) of SeNPs and sodium selenite (1 and 4 mg/kg). The data from the present study might be useful for pharmacologists and toxicologists in providing future directions while designing selenium-based therapeutic strategies.
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Affiliation(s)
- Prashanth Kondaparthi
- Department of Pharmacology and Toxicology/Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER-R), Bijnor-Sisendi Road, P.O. Mati, Lucknow, UP, 226002, India
| | - Monika Deore
- Department of Pharmacology and Toxicology/Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER-R), Bijnor-Sisendi Road, P.O. Mati, Lucknow, UP, 226002, India
| | - Saba Naqvi
- Department of Pharmacology and Toxicology/Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER-R), Bijnor-Sisendi Road, P.O. Mati, Lucknow, UP, 226002, India
| | - Swaran Jeet Singh Flora
- Department of Pharmacology and Toxicology/Regulatory Toxicology, National Institute of Pharmaceutical Education and Research (NIPER-R), Bijnor-Sisendi Road, P.O. Mati, Lucknow, UP, 226002, India.
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Javdani M, Habibi A, Shirian S, Kojouri GA, Hosseini F. Effect of Selenium Nanoparticle Supplementation on Tissue Inflammation, Blood Cell Count, and IGF-1 Levels in Spinal Cord Injury-Induced Rats. Biol Trace Elem Res 2019; 187:202-211. [PMID: 29730750 DOI: 10.1007/s12011-018-1371-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/27/2018] [Indexed: 01/06/2023]
Abstract
Selenium is known to be a neuroprotective agent in respect to a number of neuronal diseases and pain. The aim of this study was to evaluate the neuroprotective effect of the oral administration of selenium nanoparticles in rats with spinal cord injury (SCI). Forty adult female rats were randomly assigned to two equal groups as experimental and control. Under general inhalation anesthesia, in both groups, SCI was created, at the T9-10 level of the column. On the third day after the operation, a supplement of selenium nanoparticle was administered to the experimental group at 0.2 mg/kg per day. The histology of the site of injury, IGF-1 serum concentrations, and changes in the white blood cells were examined in both groups at different pre-surgical and post-surgical times. The results of the current study showed a significant decrease in the total white blood cells, including lymphocyte, neutrophil, and monocyte in the experimental group compared to the control group. Histological evaluation showed that the inflammatory responses reduced significantly in the experimental group compared to the control group. In conclusion, we speculate that the decrease in the number of inflammatory cells after oral administration of the selenium nanoparticles is due to the neuroprotective effects of this nanoparticle.
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Affiliation(s)
- Moosa Javdani
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, P.O. 88186-34141, Shahrekord, Iran.
| | - Atefeh Habibi
- Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
| | - Sadegh Shirian
- Department of Pathobiology, Faculty of Veterinary Medicine, Shahrekord University, P.O. 88186-34141, Shahrekord, Iran
| | - Gholam Ali Kojouri
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, P.O. 88186-34141, Shahrekord, Iran
| | - Farzaneh Hosseini
- Department of Veterinary Surgery and Radiology, Faculty of Veterinary Medicine, Shahrekord University, P.O. 88186-34141, Shahrekord, Iran
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Finger JW, Hamilton MT, Glenn TC, Tuberville TD. Dietary Selenomethionine Administration in the American Alligator (Alligator mississippiensis): Hepatic and Renal Se Accumulation and Its Effects on Growth and Body Condition. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2017; 72:439-448. [PMID: 28150020 DOI: 10.1007/s00244-017-0370-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/17/2017] [Indexed: 06/06/2023]
Abstract
Selenium (Se) is an essential trace nutrient, but in excess, it can induce toxicity. Incomplete combustion of coal produces coal combustion wastes, which are enriched in Se and often disposed of in aquatic basins. While a multitude of studies have investigated Se accumulation in vertebrates, few studies have examined its effects on longer-lived top trophic carnivores, such as the American alligator (Alligator mississippiensis). In this study, alligators were fed one of three Dietary Treatments: mice injected with water (controls) or water supplemented with 1000 or 2000 ppm selenomethionine (SeMet). Dietary Treatment significantly affected Se levels in both the liver (p < 0.0001; raw mean ± SE: 1000 ppm group, 35.20 ± 6.32 ppm; 2000 ppm group, 49.97 ± 4.00 ppm) and kidney (p < 0.0001; raw mean ± SE: 1000 ppm group, 101.60 ± 8.64 ppm; 2000 ppm, 96.38 ± 5.81 ppm), which were significantly higher in alligators fed SeMet than in controls. Post-treatment head length, used to control for size variation, was negatively related to both kidney (p = 0.0142) and liver (p = 0.0010) Se concentrations. Dietary treatment with SeMet significantly reduced body condition (1000 ppm, p < 0.0029; 2000 ppm, p = 0.0075), but it significantly increased growth (1000 ppm, p < 0.0001; 2000 ppm, p = 0.0316). Body condition and growth remained unchanged in control alligators (p > 0.05). Our results demonstrate alligators are capable of accumulating high levels of Se through trophic transfer. The positive effects of accumulation on growth may demonstrate Se essentiality, whereas the negative effects on condition may demonstrate toxicity. Accumulation also was associated with mortality, further demonstrating toxicity. Future studies should further investigate the physiological effects of Se accumulation in long-lived, top-trophic carnivores.
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Affiliation(s)
- John W Finger
- Department of Environmental Health Science, University of Georgia, Athens, GA, 30602, USA.
- Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, SC, 29802, USA.
- Interdisciplinary Toxicology Program, University of Georgia, Athens, GA, 30602, USA.
- Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA.
| | - Matthew T Hamilton
- Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, SC, 29802, USA
| | - Travis C Glenn
- Department of Environmental Health Science, University of Georgia, Athens, GA, 30602, USA
- Interdisciplinary Toxicology Program, University of Georgia, Athens, GA, 30602, USA
| | - Tracey D Tuberville
- Savannah River Ecology Laboratory, University of Georgia, PO Drawer E, Aiken, SC, 29802, USA
- Interdisciplinary Toxicology Program, University of Georgia, Athens, GA, 30602, USA
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López-Paniagua M, Nieto-Miguel T, de la Mata A, Galindo S, Herreras JM, Corrales RM, Calonge M. Successful Consecutive Expansion of Limbal Explants Using a Biosafe Culture Medium under Feeder Layer-Free Conditions. Curr Eye Res 2016; 42:685-695. [PMID: 27911610 DOI: 10.1080/02713683.2016.1250278] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE Transplantation of in vitro cultured limbal epithelial stem cells (LESCs) is a treatment widely used for LESC deficiency. However, the number of limbal tissue donors is limited, and protocols for LESC cultivation often include compounds and/or feeder layers that can induce side effects and/or increase the cost of the culture procedure. We investigated the feasibility of obtaining more than one limbal primary culture (LPC) from the same biopsy using a culture medium in which several potentially harmful compounds were replaced at the same time by biosafe supplements, allowing the LESC cultivation without feeder layers. MATERIALS AND METHODS We established feeder layer-free LPCs with three culture media: (1) a modified supplemental hormonal epithelial medium, containing potential harmful components (cholera toxin, dimethylsulfoxide, and fetal bovine serum [FBS]), (2) IOBA-FBS, a medium with FBS but with no other harmful supplements, and (3) IOBA-HS, similar to IOBA-FBS but with human serum instead of FBS. Additionally, the same limbal explant was consecutively cultured with IOBA-HS producing three cultures. LPCs were characterized by real-time reverse transcription polymerase chain reaction and/or immunofluorescence. RESULTS LPCs cultured with the three media under feeder layer-free conditions showed cuboidal cells and no significant differences in the percentage of positive cells for limbal (ABCG2, p63, and K14) and corneal (K3, K12) proteins. Except for ABCG2, the relative mRNA expression of the LESC markers was significantly higher when IOBA-FBS or IOBA-HS was used. LPC1 showed characteristics similar to LPC0, while LPC2 cell morphology became elongated and the expression of some LESC markers was diminished. CONCLUSION IOBA-HS enables the culturing of up to two biosafe homologous LPCs from one limbal tissue under feeder layer-free conditions. The routine use of this culture medium could improve both the biosafety and the number of available LPCs for potential clinical transplantation, as well as decrease the expense of the culture procedure.
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Affiliation(s)
- Marina López-Paniagua
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
| | - Teresa Nieto-Miguel
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
| | - Ana de la Mata
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
| | - Sara Galindo
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
| | - José M Herreras
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
| | - Rosa M Corrales
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
| | - Margarita Calonge
- a IOBA (Institute of Applied Ophthalmobiology) , University of Valladolid , Valladolid , Spain.,b CIBER-BBN (Networking Research Center on Bioengineering, Biomaterials, and Nanomedicine) , Valladolid , Spain
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Thomsen KL, Grønbæk H, Glavind E, Hebbard L, Jessen N, Clouston A, George J, Vilstrup H. Experimental nonalcoholic steatohepatitis compromises ureagenesis, an essential hepatic metabolic function. Am J Physiol Gastrointest Liver Physiol 2014; 307:G295-301. [PMID: 24924745 DOI: 10.1152/ajpgi.00036.2014] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Nonalcoholic steatohepatitis (NASH) is increasing in prevalence, yet its consequences for liver function are unknown. We studied ureagenesis, an essential metabolic liver function of importance for whole body nitrogen homeostasis, in a rodent model of diet-induced NASH. Rats were fed a high-fat, high-cholesterol diet for 4 and 16 wk, resulting in early and advanced experimental NASH, respectively. We examined the urea cycle enzyme mRNAs in liver tissue, the hepatocyte urea cycle enzyme proteins, and the in vivo capacity of urea-nitrogen synthesis (CUNS). Early NASH decreased all of the urea cycle mRNAs to an average of 60% and the ornithine transcarbamylase protein to 10%, whereas the CUNS remained unchanged. Advanced NASH further decreased the carbamoyl phosphate synthetase protein to 63% and, in addition, decreased the CUNS by 20% [from 5.65 ± 0.23 to 4.58 ± 0.30 μmol × (min × 100 g)(-1); P = 0.01]. Early NASH compromised the genes and enzyme proteins involved in ureagenesis, whereas advanced NASH resulted in a functional reduction in the capacity for ureagenesis. The pattern of urea cycle perturbations suggests a prevailing mitochondrial impairment by NASH. The decrease in CUNS has consequences for the ability of the body to adjust to changes in the requirements for nitrogen homeostasis e.g., at stressful events. NASH, thus, in terms of metabolic consequences, is not an innocuous lesion, and the manifestations of the damage seem to be a continuum with increasing disease severity.
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Affiliation(s)
- Karen Louise Thomsen
- Department of Hepatology & Gastroenterology, Aarhus University Hospital, Aarhus, Denmark;
| | - Henning Grønbæk
- Department of Hepatology & Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Emilie Glavind
- Department of Hepatology & Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
| | - Lionel Hebbard
- Storr Liver Unit, Westmead Millennium Institute and Westmead Hospital, University of Sydney, Westmead, Australia
| | - Niels Jessen
- Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark; The Medical Research Laboratory, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; and
| | - Andrew Clouston
- Centre for Liver Disease Research, School of Medicine, University of Queensland, Brisbane, Australia
| | - Jacob George
- Storr Liver Unit, Westmead Millennium Institute and Westmead Hospital, University of Sydney, Westmead, Australia
| | - Hendrik Vilstrup
- Department of Hepatology & Gastroenterology, Aarhus University Hospital, Aarhus, Denmark
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Martiniaková M, Boboňová I, Omelka R, Grosskopf B, Chovancová H, Španková J, Toman R. Simultaneous subchronic exposure to selenium and diazinon as possible risk factor for osteoporosis in adult male rats. Acta Vet Scand 2013; 55:81. [PMID: 24237628 PMCID: PMC3843554 DOI: 10.1186/1751-0147-55-81] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 11/13/2013] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Osteoporosis and its main health outcome, fragility fractures, are large and escalating health problems. Skeletal damage may be the critical result of low-level prolonged exposure to several xenobiotics in the general population, but the mechanisms of their adverse effects are not clearly understood. The current study was aimed to investigate the possible ability of simultaneous subchronic peroral administration of selenium (Se) and diazinon (DZN) to induce changes in bone of adult male rats.In our study, twenty 1-month-old male Wistar rats were randomly divided into two experimental groups. In the first group, young males were exposed to 5 mg Na2SeO3/L and 40 mg of DZN/L in drinking water, for 90 days. Ten 1-month-old males without Se and DZN intoxication served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy. RESULTS The body weight, femoral length and cortical bone thickness were significantly decreased in rats simultaneously exposed to Se and DZN (P < 0.05). These rats also displayed different microstructure in the middle part of the compact bone where vascular canals expanded into central area of substantia compacta. The canals occurred only near endosteal surfaces in rats from the control group. Additionally, a smaller number of primary and secondary osteons, as well as a few resorption lacunae were observed near endosteal surfaces in rats simultaneously administered to Se and DZN. The resorption lacunae as typical structures of bone resorption manifestation are connected with an early stage of osteoporosis. Histomorphometric analysis revealed that area, perimeter, maximum and minimum diameters of primary osteons' vascular canals were significantly increased (P < 0.05) in the Se-DZN-exposed rats. On the other hand, all measured variables of Haversian canals and secondary osteons were considerable reduced (P < 0.05) in these rats. CONCLUSIONS Simultaneous subchronic peroral exposure to Se and DZN induces changes in macroscopic and microscopic structures of the femurs in adult male rats, and also it can be considered as possible risk factor for osteoporosis. The current study contributes to the knowledge on damaging impact of several xenobiotics on the bone.
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López-Paniagua M, Nieto-Miguel T, de la Mata A, Galindo S, Herreras JM, Corrales RM, Calonge M. Consecutive Expansion of Limbal Epithelial Stem Cells from a Single Limbal Biopsy. Curr Eye Res 2013; 38:537-49. [DOI: 10.3109/02713683.2013.767350] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Martiniaková M, Boboňová I, Omelka R, Grosskopf B, Stawarz R, Toman R. Structural changes in femoral bone tissue of rats after subchronic peroral exposure to selenium. Acta Vet Scand 2013; 55:8. [PMID: 23369508 PMCID: PMC3598879 DOI: 10.1186/1751-0147-55-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 01/29/2013] [Indexed: 11/19/2022] Open
Abstract
Background The role of selenium (Se) on bone microarchitecture is still poorly understood. The present study aims to investigate the macroscopic and microscopic structures of femoral bone tissue in adult male rats after subchronic peroral administration of Se. Methods Twenty one-month-old male Wistar rats were randomly divided into two experimental groups. In the first group (Se group) young males were exposed to 5 mg Na2SeO3/L in drinking water, for 90 days. Ten one-month-old males without Se administration served as a control group. At the end of the experiment, macroscopic and microscopic structures of the femurs were analysed using analytical scales, sliding instrument, and polarized light microscopy. Results The body weight, femoral length and cortical bone thickness were significantly decreased in Se group rats. These rats also displayed different microstructure in the middle part of the femur, both in medial and lateral views, where vascular canals expanded into the central area of the bone while, in control rats, these canals occurred only near the endosteal surfaces. Additionally, a smaller number of primary and secondary osteons was identified in Se group rats. Histomorphometric analyses revealed significant increases for area, perimeter, maximum and minimum diameters of primary osteons’ vascular canals but significant reductions for all measured variables of Haversian canals and secondary osteons. Conclusions Se negatively affected the macroscopic and microscopic structures of femoral bone tissue in adult male rats. The results contribute to the knowledge on damaging impact of Se on bone.
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Shakibaie M, Shahverdi AR, Faramarzi MA, Hassanzadeh GR, Rahimi HR, Sabzevari O. Acute and subacute toxicity of novel biogenic selenium nanoparticles in mice. PHARMACEUTICAL BIOLOGY 2013; 51:58-63. [PMID: 23035822 DOI: 10.3109/13880209.2012.710241] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
CONTEXT In the present investigation, acute and subacute toxicity of the biogenic Se nanoparticles (Se NPs) has been reported. OBJECTIVE To characterize the Se NPs produced by a bacterium species and to evaluate their toxicity and impact on clinical chemistry and hematological parameters of NMRI mice. MATERIALS AND METHODS The Se NPs were prepared by Bacillus sp. MSh-1 in a culture medium containing SeO(2) (1.26 mM) and their physiochemical properties investigated using TEM, XRD and FT-IR. The LD(50) of Se NPs and SeO(2) were determined and the subacute toxicity evaluated by orally administration of 0, 2.5, 5, 10 and 20 mg kg(-1) of Se NPs to male mice for 14 consecutive days. Parameters of blood cells, AST, ALT, ALP, creatinine, BUN, cholesterol, bilirubin, triglyceride and CPK were experimentally measured. RESULTS The XRD and TEM analyses showed that the spherical NPs were amorphous, in the size range of 80-220 nm. The toxicological evaluation showed that the LD(50) values of SeO(2) and Se NPs were 7.3 and 198.1 mg kg(-1), respectively. No biochemical changes were observed from the administration of 2.5, 5 and 10 mg kg(-1) of Se NPs, but a dose of 20 mg kg(-1) was accompanied with signs of toxicity including lower body weight and changes in clinical chemistry and hematological parameters. CONCLUSION The biogenic Se NPs were less toxic than synthetic Se NPs and much less (26-fold) toxic than the SeO(2), which demonstrates the important role of Bacillus sp. MSh-1 in conversion of a highly toxic Se compound to the less toxic Se NPs.
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Affiliation(s)
- Mojtaba Shakibaie
- Pharmaceutics Research Center, Kerman University of Medical Sciences, Kerman, Iran
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Thomsen KL, Aagaard NK, Nielsen SS, Grønbaek H, Jessen N, Frystyk J, Vilstrup H. Unchanged capacity of urea synthesis during acute phase response in rats. Eur J Clin Invest 2011; 41:16-22. [PMID: 20731702 DOI: 10.1111/j.1365-2362.2010.02369.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND The acute phase response presents a catabolic event related to increased waste of amino-N via hepatic urea synthesis despite an increased need for amino-N incorporation into acute phase proteins. In our previous studies, tumour necrosis factor-α (TNF-α) acutely up-regulated the in vivo capacity of urea-nitrogen synthesis (CUNS) in rats before the hepatic acute phase response was established. To extend these observations, this study aimed to clarify the regulation of N elimination via urea during the later stages of the acute phase response. METHODS Twenty-four hours after i.v. injection of 25 μg kg(-1) TNF-α or placebo, we determined the in vivo CUNS, hepatocyte urea cycle enzyme protein levels and mRNA levels of the urea cycle enzyme genes in pair-fed rats. In addition, serum acute phase proteins and their liver mRNA levels were measured. RESULTS After TNF-α, CUNS and hepatocyte urea cycle enzyme protein expressions were unchanged while urea cycle enzyme mRNA levels decreased. Liver mRNA levels of α2MG, haptoglobin and α1AGP rose and their serum levels increased equally. CONCLUSION Despite a fully established 24-h acute phase response, there was no change in the in vivo capacity for disposal of amino-N by urea synthesis or in the urea cycle enzyme proteins, although the expression of the urea cycle enzyme genes was decreased. Thus, in vivo urea synthesis was not orchestrated together with acute phase protein synthesis so as to limit N waste despite genetic regulation to this effect. This may contribute towards catabolism of inflammation.
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Affiliation(s)
- Karen L Thomsen
- Department of Medicine V (Hepatology and Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark.
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Thomsen KL, Aagaard NK, Grønbæk H, Holst JJ, Jessen N, Frystyk J, Vilstrup H. IL-6 has no acute effect on the regulation of urea synthesis in vivo in rats. Scand J Clin Lab Invest 2010; 71:150-6. [PMID: 21190512 DOI: 10.3109/00365513.2010.547213] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Clinical or experimentally induced, active inflammation up-regulates the in vivo capacity of urea synthesis (CUNS), which promotes nitrogen removal from the body and metabolic catabolism. We have shown that tumor necrosis factor α (TNF-α) up-regulates CUNS and increases interleukin 6 expression (IL-6) within hours of administration. The described effect of TNF-α on nitrogen homeostasis may, therefore, depend on IL-6. METHODS Three hours after the i.v. injection of 125 μg.kg⁻¹ of IL-6 or placebo, we evaluated the CUNS, hepatocyte urea cycle enzyme protein levels and the mRNA levels of the urea cycle enzyme genes in rats. The prevailing rat serum acute phase proteins and their liver mRNA levels were also measured. RESULTS IL-6 did not change CUNS or hepatocyte urea cycle enzyme protein levels, whereas urea cycle enzyme mRNA levels, except for ornithine transcarbamylase (OTC), decreased by approximately 20%. The liver mRNA levels of α2MG, haptoglobin and α1AGP all increased by 1.5- to 2-fold (p < 0.001). In serum, only the α2MG concentration slightly increased (p < 0.001), whereas the levels of the other circulating acute phase proteins remained unchanged. CONCLUSION IL-6 is not the mediator of the in vivo CUNS up-regulation observed 3 h after TNF-α administration, but it may be involved in the down-regulation of urea cycle genes. IL-6 may also mediate TNF-α effects on acute phase protein gene expression. Thus, IL-6 did not contribute to the in vivo hepatic component of inflammation-associated catabolism.
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Affiliation(s)
- Karen L Thomsen
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark.
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Thomsen KL, Nielsen SS, Aagaard NK, Sandahl TD, Grønbæk H, Frystyk J, Flyvbjerg A, Vilstrup H. Tumor necrosis factor-α acutely up-regulates urea synthesis in vivo in rats – a hepatic component of inflammatory catabolism? Scandinavian Journal of Clinical and Laboratory Investigation 2010; 70:151-7. [DOI: 10.3109/00365511003599537] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Karen L. Thomsen
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark
| | - Susanne S. Nielsen
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark
| | - Niels K. Aagaard
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark
| | - Thomas D. Sandahl
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark
| | - Henning Grønbæk
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark
| | - Jan Frystyk
- The Medical Research Laboratories, Clinical Institute, Aarhus University Hospital, Aarhus C, Denmark
| | - Allan Flyvbjerg
- The Medical Research Laboratories, Clinical Institute, Aarhus University Hospital, Aarhus C, Denmark
| | - Hendrik Vilstrup
- Department of Medicine V (Hepatology & Gastroenterology), Aarhus University Hospital, Aarhus C, Denmark
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Tuji FM, Pontual MLDA, Barros SP, Almeida SMD, Bóscolo FN. Ultrastructural assessment of the radioprotective effects of sodium selenite on parotid glands in rats. J Oral Sci 2010; 52:369-75. [DOI: 10.2334/josnusd.52.369] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Pontual MLDA, Tuji FM, Barros SP, Bóscolo FN, Novaes PD, de Almeida SM. Ultrastructural evaluation of the radioprotective effect of sodium selenite on submandibular glands in rats. J Appl Oral Sci 2009; 15:162-8. [PMID: 19089124 PMCID: PMC4327461 DOI: 10.1590/s1678-77572007000300003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2005] [Accepted: 03/22/2007] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to evaluate the radioprotector effect of sodium selenite on the ultrastructure of submandibular glands in rats. Fifty-seven male albino Wistar rats were randomized to 4 groups: control, irradiated, sodium selenite and irradiated/sodium selenite. The animals in the sodium selenite and irradiated/sodium selenite groups received intraperitoneal injections of sodium selenite (0.5 mg/kg body weight) 24 h before irradiation. The animals belonging to the irradiated and irradiated/sodium selenite groups were submitted to 15 Gy of gamma radiation in the head and neck region. The submandibular glands were removed at 4, 8, 12, 24, 48 and 72 h after irradiation. The ionizing radiation induced damage to the secretory cells, especially the serous cells, right from the first period. Vacuolization, lysis of cytoplasmic inclusions and nuclear alterations occurred. The sodium selenite group also presented cellular alterations in the study periods, but with less damage compared to that caused by radiation. There was greater similarity between the irradiated/sodium selenite group and the control group than with the other groups treated in all study periods. Despite the alterations observed in the sodium selenite group, sodium selenite presented a radioprotective action on the secretory cells of submandibular glands.
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Affiliation(s)
- Maria Luiza dos Anjos Pontual
- Department of Clinic and Social Dentistry, School of Dentistry, Federal University of Paraíba, João Pessoa, PB, Brazil.
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Karl JP, Alemany JA, Koenig C, Kraemer WJ, Frystyk J, Flyvbjerg A, Young AJ, Nindl BC. Diet, body composition, and physical fitness influences on IGF-I bioactivity in women. Growth Horm IGF Res 2009; 19:491-496. [PMID: 19467892 DOI: 10.1016/j.ghir.2009.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Revised: 04/16/2009] [Accepted: 04/22/2009] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Insulin-like growth factor I (IGF-I) is a metabolic-regulatory hormone that mediates a variety of physiologic functions. Body composition, fitness status and intake of certain micro- and macronutrients are associated with circulating concentrations of immunoreactive IGF-I. The influence of these factors on IGF-I bioactivity; however, is undetermined. We assessed the relationships between IGF-I bioactivity and lifestyle factors purportedly associated with IGF-I immunoreactivity. DESIGN In a cross sectional study, fasted blood samples were obtained from 44 lightly active, college-age (20+/-2 yrs) women. IGF-I bioactivity was estimated by an assay which determines the ability of serum IGFs to phosphorylate IGF-I receptors in cultured cells; free and total IGF-I were measured by immunoassay. Estradiol and progesterone were measured by immunoassay. Body mass index was calculated from measured height and weight, bone mineral density and body fat percentage measured by dual energy X-ray absorptiometry, and peak oxygen consumption (VO(2peak)) determined during a graded treadmill protocol. A food frequency questionnaire measured habitual and a 5-day food record assessed short-term micro- and macronutrient intakes. Associations between bioactive, free and total IGF-I with body composition, sex hormones, VO(2peak), and dietary intake were assessed using univariate and multiple linear regression analyses. RESULTS Associations between bioactive IGF-I with age (r=-0.36, P<0.05), body fat percentage (r=-0.32, P<0.05), estradiol (r=0.31, P<0.05) and progesterone (r=0.33, P<0.05) concentrations, habitual alcohol (r=-0.38, P<0.05) and selenium intakes (r=0.41, P<0.01), free IGF-I with age (r=-0.34, P<0.05), estradiol (r=0.48, P<0.01) and progesterone (r=0.52, P<0.001) concentrations, habitual alcohol (r=-0.33, P<0.05) and isoflavone intakes (r=0.30, P<0.05) and total IGF-I with age (r=-0.27, P<0.05) and habitual alcohol intake (r=-0.33, P<0.05) were observed. Habitual alcohol intake was a negative predictor of bioactive, free and total IGF-I in multivariate models. CONCLUSION Of the lifestyle factors measured, the most robust relationship observed was a negative association between habitual alcohol intake and all measures of IGF-I. This finding suggests that alcohol intake may blunt the physiologic actions of the IGF-I axis.
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Affiliation(s)
- J Philip Karl
- US Army Research Institute of Environmental Medicine, 42 Kansas St., Natick, MA 01760, USA
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17
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Xu R. Effect of whey protein on the proliferation and differentiation of osteoblasts. J Dairy Sci 2009; 92:3014-8. [DOI: 10.3168/jds.2008-1702] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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18
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L-selenomethionine as a source of selenium added for nutritional purposes to food supplements. EFSA J 2009. [DOI: 10.2903/j.efsa.2009.1082] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Pappas A, Zoidis E, Surai P, Zervas G. Selenoproteins and maternal nutrition. Comp Biochem Physiol B Biochem Mol Biol 2008; 151:361-72. [DOI: 10.1016/j.cbpb.2008.08.009] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 08/13/2008] [Accepted: 08/20/2008] [Indexed: 11/24/2022]
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20
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Ward MA, Neville TL, Reed JJ, Taylor JB, Hallford DM, Soto-Navarro SA, Vonnahme KA, Redmer DA, Reynolds LP, Caton JS. Effects of selenium supply and dietary restriction on maternal and fetal metabolic hormones in pregnant ewe lambs1. J Anim Sci 2008; 86:1254-62. [DOI: 10.2527/jas.2007-0509] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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21
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Juniper DT, Phipps RH, Givens DI, Jones AK, Green C, Bertin G. Tolerance of ruminant animals to high dose in-feed administration of a selenium-enriched yeast1. J Anim Sci 2008; 86:197-204. [PMID: 17878272 DOI: 10.2527/jas.2006-773] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The objective of the study was to determine if there were adverse effects on animal health and performance when a range of ruminant animal species were fed at least 10 times the maximum permitted European Union (EU) Se dietary inclusion rate (0.568 mg of Se/kg of DM) in the form of Se-enriched yeast (SY) derived from a specific strain of Saccharomyces cerevisiae, CNCM I-3060. In a series of studies, dairy cows, beef cattle, calves, and lambs were offered a control diet that contained no Se supplement or a treatment diet that contained the same basal feed ingredients plus a SY supplement that increased total dietary Se from 0.15 to 6.25, 0.20 to 6.74, 0.15 to 5.86, and 0.14 to 6.63 mg of Se/kg of DM, respectively. The inclusion of the SY supplement increased (P < 0.001) whole-blood Se concentrations, reaching maximum mean values of 716, 1,505, 1,377, and 724 ng of Se/mL for dairy cattle, beef cattle, calves, and lambs, respectively. Seleno-methionine accounted for 10% of total whole-blood Se in control animals, whereas the proportion in SY animals ranged between 40 and 75%. Glutathione peroxidase (EC 1.11.1.9) activity was greater (P < 0.05) in SY animals compared with controls. A range of other biochemical and hematological parameters were assessed, but few differences of biological significance were established between treatment groups. There were no differences between treatment groups within each species with regard to animal physical performance or overall animal health. It was concluded that there were no adverse effects on animal health, performance, and voluntary feed intake with the administration of at least 10 times the EU maximum, or approximately 20 times the US Food and Drug Administration permitted concentration of dietary Se in the form of SY derived from a specific strain of Saccharomyces cerevisiae CNCM I-3060.
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Affiliation(s)
- D T Juniper
- Animal Science Research Group, School of Agriculture, Policy and Development University of Reading, Earley Gate, Reading RG6 6AR, UK.
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Wang H, Zhang J, Yu H. Elemental selenium at nano size possesses lower toxicity without compromising the fundamental effect on selenoenzymes: comparison with selenomethionine in mice. Free Radic Biol Med 2007; 42:1524-33. [PMID: 17448899 DOI: 10.1016/j.freeradbiomed.2007.02.013] [Citation(s) in RCA: 415] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2006] [Revised: 02/05/2007] [Accepted: 02/10/2007] [Indexed: 11/22/2022]
Abstract
Glutathione peroxidase and thioredoxin reductase are major selenoenzymes through which selenium exerts powerful antioxidant effects. Selenium also elicits pro-oxidant effects at toxic levels. The antioxidant and pro-oxidant effects, or bioavailability and toxicity, of selenium depend on its chemical form. Selenomethionine is considered to be the most appropriate supplemental form due to its excellent bioavailability and lower toxicity compared to various selenium compounds. The present studies reveal that, compared with selenomethionine, elemental selenium at nano size (Nano-Se) possesses equal efficacy in increasing the activities of glutathione peroxidase and thioredoxin reductase but has much lower toxicity as indicated by median lethal dose, acute liver injury, and short-term toxicity. Our results suggest that Nano-Se can serve as an antioxidant with reduced risk of selenium toxicity.
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Affiliation(s)
- Huali Wang
- University of Science and Technology of China, Hefei 230052, People's Republic of China
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Abstract
Recent identification of new selenocysteine-containing proteins has revealed relationships between the two trace elements selenium (Se) and iodine and the hormone network. Several selenoproteins participate in the protection of thyrocytes from damage by H(2)O(2) produced for thyroid hormone biosynthesis. Iodothyronine deiodinases are selenoproteins contributing to systemic or local thyroid hormone homeostasis. The Se content in endocrine tissues (thyroid, adrenals, pituitary, testes, ovary) is higher than in many other organs. Nutritional Se depletion results in retention, whereas Se repletion is followed by a rapid accumulation of Se in endocrine tissues, reproductive organs, and the brain. Selenoproteins such as thioredoxin reductases constitute the link between the Se metabolism and the regulation of transcription by redox sensitive ligand-modulated nuclear hormone receptors. Hormones and growth factors regulate the expression of selenoproteins and, conversely, Se supply modulates hormone actions. Selenoproteins are involved in bone metabolism as well as functions of the endocrine pancreas and adrenal glands. Furthermore, spermatogenesis depends on adequate Se supply, whereas Se excess may impair ovarian function. Comparative analysis of the genomes of several life forms reveals that higher mammals contain a limited number of identical genes encoding newly detected selenocysteine-containing proteins.
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Affiliation(s)
- J Köhrle
- Institut für Experimentelle Endokrinologie, Charité, Humboldt Universität zu Berlin, Schumannstrasse 20/21, D-10098 Berlin, Germany.
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Zhang J, Wang H, Yan X, Zhang L. Comparison of short-term toxicity between Nano-Se and selenite in mice. Life Sci 2005; 76:1099-109. [PMID: 15620574 DOI: 10.1016/j.lfs.2004.08.015] [Citation(s) in RCA: 191] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2004] [Accepted: 08/10/2004] [Indexed: 10/26/2022]
Abstract
We previously reported that, as compared with selenite, nano red elemental selenium (Nano-Se) had lower acute toxicity in mice and similar bioavailability in terms of up-regulating seleno-enzymes. The short-term toxicity of both selenite and Nano-Se in mice was further compared in this study. At an oral dose of 6 mg/kg bw per day administered for consecutive 12 days, selenite and Nano-Se completely and partially suppressed mice growth respectively. Abnormal liver function was more pronounced with selenite treatment than Nano-Se as indicated by the increase of both alanine aminotransferase and aspartate aminotransferase in serum. Selenite inhibited liver catalase and superoxide dismutase activities, whereas, Nano-Se did not affect these two antioxidant enzymes. Selenite increased the malondialdehyde content of liver, but Nano-Se decreased it. Both Se forms had similar effects on depletion of reduced glutathione and up-regulated glutathione peroxidase. Nano-Se was more potent than selenite in the induction of glutathione S-transferase. At oral doses of 2 or 4 mg/kg bw per day for consecutive 15 days, selenite was more active than Nano-Se in supressing growth, deleting reduced glutathione, and inhibiting superoxide dismutase activities. Taken together, these results indicate that over a short-term, a high-dose of selenite caused more pronounced oxidative stress, greater liver injury, and prominent retardation of growth as compared to Nano-Se.
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Affiliation(s)
- Jinsong Zhang
- University of Science and Technology of China, Hefei, 230052 P.R. China.
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Viidik A, Skalicky M. Voluntary exercise and mild food restriction effectively retard the collagen biomarker of aging. Aging Clin Exp Res 2003; 15:475-81. [PMID: 14959950 DOI: 10.1007/bf03327370] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND AIMS Obesity and lack of physical exercise characterize increasing numbers of people in Western societies, resulting in increasing morbidity and mortality. Regular physical exercise, on the other hand, has been shown to be beneficial. Beneficial effects have also been shown in laboratory rodent studies--lifelong physical exercise increases the mean life span but not the maximum life span, while food restriction increases both life spans. We studied male Sprague-Dawley rats in order to further analyze these beneficial effects. METHODS We compared voluntary running in wheels (RW) with food restriction to pair weight with RW (PW), and mild forced running in treadmill (TM)--all animals housed individually. Control groups were sedentary ad libitum-fed animals housed individually (S1) and four to a cage (S4). The collagen biomarker of aging was calculated as a composite parameter from thermal stability data for 5 (baseline), 15, 19 and 23 months of age. RESULTS In RW and PW, the increase in the composite parameter was retarded to the same extent. The retardation in TM was less efficient. S4 had the highest value for the composite parameter, together with the highest body weight and fat content. In groupwise comparisons, the composite parameter tended to predict survival in the groups up to the age of 23 months. CONCLUSIONS Voluntary running in wheels is more beneficial than mild-forced exercise on the treadmill. The composite parameter is a useful indicator of different interventions on aging rats.
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Affiliation(s)
- Andrus Viidik
- Institute of Anatomy, University of Aarhus, Aarhus, Denmark.
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Skalicky M, Viidik A. Comparison between continuous and intermittent physical exercise on aging rats: changes in patterns of spontaneous activity and connective tissue stability. AGING (MILAN, ITALY) 1999; 11:227-34. [PMID: 10605611 DOI: 10.1007/bf03339663] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Life-long physical exercise increases the mean but not maximum life span of laboratory rodents. It further improves the performance in an open field setting, which suggests a delay of sensorimotor disturbances, and retards the aging increase of thermal stability of collagen. The purpose of the present study was to examine whether the amount or continuity of training is more important. We trained male Sprague-Dawley rats for 12 months from the age of 12 months in a treadmill: 1) continuously for 3 km/week (total distance covered: 144 km); 2) intermittently for 3 km/week for 8-week periods with 8-week resting periods in between (72 km), and 3) intermittently for 6 km/week for 8-week periods with 8-week resting periods in between (144 km). All training regimens prevented the increase in body weight seen in sedentary animals, although the intermittent training programs caused fluctuations with the training and resting periods. With respect to spontaneous movements in an open field setting, continuous training was most effective in counteracting age-related changes. Continuous training was also most effective for delaying age-related increase in thermal stability of collagen. We conclude that the continuity of training is more important than the amount and intensity of training.
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Affiliation(s)
- M Skalicky
- Institute of Physiology, University of Veterinary Medicine, Vienna, Austria
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Frystyk J, Grønbaek H, Skjaerbaek C, Flyvbjerg A, Orskov H, Baxter RC. Developmental changes in serum levels of free and total insulin-like growth factor I (IGF-I), IGF-binding protein-1 and -3, and the acid-labile subunit in rats. Endocrinology 1998; 139:4286-92. [PMID: 9751511 DOI: 10.1210/endo.139.10.6273] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have recently described a competitive binding assay for rat insulin-like growth factor-binding protein-3 (IGFBP-3) based on the ability of IGFBP-3 to form a ternary complex with the acid-labile subunit (ALS) in the presence of IGF-I. Using this assay we studied groups of male (n = 6) and female rats (n = 6) at 20, 30, 40, 50, 60, 80, and 130 days of age. Nonfasting serum levels of IGFBP-3 were compared with those of total (extractable) IGF-I (tIGF-I) and ALS as well as IGFBP-3 determined by ligand blotting. Additionally, we studied the relationship between ultrafiltered free IGF-I (fIGF-I) and immunoassayable IGFBP-1. IGFBP-3 was dependent on age only (P < 0.0001), but tended to be higher in males than in females (P = 0.06); between 20-130 days levels increased from 6.5 +/- 1.7 to 73.6 +/- 7.2 nmol/liter in males and from 5.4 +/- 1.6 to 51.3 +/- 8.0 nmol/liter in females. IGFBP-3 correlated positively with tIGF-I (r = 0.90; P < 0.0001), ALS (r = 0.92; P < 0.0001), and IGFBP-3, as determined by ligand blotting (r = 0.88; P < 0.0001). The molar ratio of IGFBP-3 to tIGF-I increased from 0.23 +/- 0.04 to 0.76 +/- 0.04 (P < 0.0001) without any sex dependence. An age- and sex-dependent decrease in IGFBP-1 was observed (P < 0.0001), from 10.9 +/- 2.5 to 1.2 +/- 0.2 nmol/liter in females and from 8.9 +/- 0.7 to 0.2 +/- 0.04 nmol/liter in males. Free IGF-I (fIGF-I) increased with age (from 0.7 +/- 0.2 to 7.1 +/- 0.5 nmol/liter; P < 0.0001), and levels were inversely correlated with IGFBP-1 (r = -0.80; P < 0.0001). In young rats, IGFBP-1 circulated in a 10-fold molar excess over the level of fIGF-I, whereas in older rats, fIGF-I exceeded IGFBP-1 by an average of 9-fold in females and by up to almost 60-fold in males. We conclude that in rats 1) IGFBP-3 and fIGF-I are strongly age dependent; 2) IGFBP-3 correlates positively with ALS and tIGF-I; and 3) fIGF-I and IGFBP-1 are inversely correlated. This is in accordance with clinical findings. However, in humans the adult level of fIGF-I rarely exceeds 0.3 nmol/liter, and IGFBP-1 usually circulates in excess of fIGF-I. Thus, our results also imply species differences in the IGF systems of humans and rats.
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Affiliation(s)
- J Frystyk
- Institute of Experimental Clinical Research, Medical Research Laboratories, Aarhus University Hospital, Denmark.
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Grønbaek H, Skjaerbaek C, Orskov H, Flyvbjerg A. Effect of immunosuppression on kidney and serum insulin-like growth factor-I (IGF-I), IGF binding proteins, and renal growth following unilateral nephrectomy in rats. Metabolism 1998; 47:817-23. [PMID: 9667228 DOI: 10.1016/s0026-0495(98)90119-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A rat model was used to study the role of renal insulin-like growth factor-I (IGF-I) and circulating IGF-I and IGF binding proteins (IGFBPs) in early posttransplantation renal hypertrophy and overall body growth during high-dose immunosuppression. Seven days of prednisolone and cyclosporin A (CsA) immunosuppression was administered to rats following unilateral nephrectomy compared with sham-operated controls. Immunosuppression of nephrectomized and control rats was followed by a reduction in body weight (BW) compared with placebo treatment. In addition, immunosuppression inhibited kidney IGF-I accumulation and compensatory renal growth in uninephrectomized rats, but caused no change in kidney weight or IGF-I levels in control rats. Immunosuppression induced a sustained significant increase in circulating IGFBP-3 and 30-kd IGFBPs in uninephrectomized and controls rats, whereas serum IGF-I levels were unchanged. In a supplementary study separating the effects of the two immunosuppressants, the kidney IGF-I changes and renal growth were primarily affected by CsA, while the changes in IGFBPs appeared to be caused by prednisolone treatment. In conclusion, immunosuppression with prednisolone and CsA was followed by less kidney IGF-I accumulation and compensatory renal growth compared with placebo treatment. In addition, a sustained increase in circulating levels of IGFBP-3 and 30-kd IGFBPs was observed, which may be involved in the growth impairment observed following immunosuppressive treatment.
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Affiliation(s)
- H Grønbaek
- Institute of Experimental Clinical Research, Aarhus University Hospital, Denmark
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Ortoft G, Grønbaek H, Oxlund H. Growth hormone administration can improve growth in glucocorticoid-injected rats without affecting the lymphocytopenic effect of the glucocorticoid. Growth Horm IGF Res 1998; 8:251-64. [PMID: 10984314 DOI: 10.1016/s1096-6374(98)80118-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Long-term glucocorticoid therapy as it is found in children with kidney transplants results in retarded longitudinal growth. The aim of the present study was to evaluate if growth hormone could improve longitudinal growth in glucocorticoid-injected experimental animals without affecting the immuno-suppressive effect of the glucocorticoid. 117 female Wistar rats were injected from the ages of 2-5 months with either saline, growth hormone (5 mg/kg/day), or glucocorticoid (methylprednisolone 1,3,6 or 9 mg/kg/day), alone or in combination with growth hormone (5 mg/kg/day). Body weight, nose-tail length and length of the lower extremity were measured continuously during the study. After death, femoral and tibial lengths, growth at the proximal, epiphyseal growth plate, muscle mass and immunological parameters were examined. Glucocorticoid administration dose-dependently decreased weight gain and growth (nose-tail length, growth of the lower extremity), lengths of femur and tibia, growth at the proximal, epiphyseal growth plate and muscle mass. Glucocorticoid administration decreased spleen and thymus weight as well as the white blood cell count (WBC count), mainly due to a decrease in lymphocyte number. For all glucocorticoid doses examined, growth hormone increased weight gain and growth (nose-tail length, growth of the lower extremity), lengths of femur and tibia, and muscle mass. The effects of growth hormone were, however, dose-dependently decreased by glucocorticoid administration. Growth hormone injection alone increased the WBC count due to an increase in the number of lymphocytes and monocytes. When the two hormones were administered concomitantly, growth hormone did not, however, reverse the lymphocytopenic effect induced by glucocorticoid administration. In conclusion, growth hormone can increase longitudinal growth and increase muscle mass in glucocorticoid-injected rats, if a glucocorticoid preparation of a short half-life is used. Growth hormone does not reverse the lymphocytopenic effect of glucocorticoid injections.
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Affiliation(s)
- G Ortoft
- Department of Connective Tissue Biology, Institute of Anatomy, University of Aarhus, Denmark.
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Grønbaek H, Volmers P, Bjørn SF, Osterby R, Orskov H, Flyvbjerg A. Effect of GH/IGF-I deficiency on long-term renal changes and urinary albumin excretion in diabetic dwarf rats. THE AMERICAN JOURNAL OF PHYSIOLOGY 1997; 272:E918-24. [PMID: 9176194 DOI: 10.1152/ajpendo.1997.272.5.e918] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Growth hormone (GH) and insulin-like growth factor I (IGF-I) may play a role in early diabetic renal and glomerular growth and in the later development of experimental diabetic kidney disease. Rats from a genetic GH/IGF-I-deficient dwarf rat strain were made streptozotocin diabetic and were compared with nondiabetic dwarf rats. GH/IGF-I-intact rats with and without diabetes served as controls. After 6 mo of diabetes, kidney weight and total glomerular volume increased significantly in GH/IGF-I-intact diabetic rats compared with the nondiabetic GH/IGF-I-intact rats (P < 0.05), whereas the diabetic dwarf rats had insignificant changes compared with dwarf control rats. By the end of the study, urinary albumin excretion (UAE) increased from similar base levels of approximately 15-20 micrograms/24 h to 473 +/- 52 (SE) micrograms/24 h in GH/IGF-I-intact diabetic rats compared with 151 +/- 32 micrograms/24 h in diabetic dwarf rats (P < 0.01). In conclusion, isolated GH/IGF-I deficiency reduces the degree of renal and glomerular hypertrophy and the increase in UAE after 6 mo of experimental diabetes in GH/IGF-I-deficient rats.
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Affiliation(s)
- H Grønbaek
- Electron Microscopical Diabetes Research Laboratory, University Institute of Pathology, Aarhus Kommunehospital, Denmark
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Grønboek H, Nielsen B, Flyvbjerg A, Orskov H. Effect of graded renal ablation on kidney and serum insulin-like growth factor-I (IGF-I) and IGF binding proteins in rats: relation to compensatory renal growth. Metabolism 1997; 46:29-35. [PMID: 9005965 DOI: 10.1016/s0026-0495(97)90163-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Kidney insulin-like growth factor-I (IGF-I) increases transiently following unilateral nephrectomy, thus preceding the compensatory renal growth. The aim of the present study was to investigate the effect of different degrees (1/7 to 2/3) of renal ablation on kidney and serum IGF-I and IGF binding proteins (IGFBPs) during a 7-day study period. All nephrectomized rats exhibited an increase in the weight of the remaining renal tissue. Kidney IGF-I measured in kidney pieces close to and away from the resected area increased transiently and more significantly away from the resected area, with significant correlation to the amount of tissue resected (day 1, r = .73, P < .0001; day 2, r = .49, P < .05; and day 7, r = .48, P < .05). No changes in kidney IGFBPs or serum IGF-I were observed. Serum IGFBP-4 correlated to the degree of renal resection, as did changes in serum urea and creatinine. In conclusion, significant correlations were observed between local changes in kidney IGF-I and serum IGFBP-4 levels and the degree of renal ablation, suggesting a role for IGF-I as a renotropic factor and, further, that IGFBP-4 is removed to a major extent through the kidney.
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Affiliation(s)
- H Grønboek
- Institute of Experimental Clinical Research, Aarhus University Hospital, Denmark
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