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Chen J, Yang W, Liu H, Niu J, Liu Y, Cheng Q. Protective effect of Macleaya cordata isoquinoline alkaloids on lipopolysaccharide-induced liver injury in broilers. Anim Biosci 2024; 37:131-141. [PMID: 37946426 PMCID: PMC10766460 DOI: 10.5713/ab.23.0267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 08/29/2023] [Accepted: 09/18/2023] [Indexed: 11/12/2023] Open
Abstract
OBJECTIVE This experiment aimed to explore the protective action of dietary supplementation with isoquinoline alkaloids (IA) from Macleaya cordata on lipopolysaccharide (LPS)-induced liver injury in broilers. METHODS Total 216 healthy broilers were selected in a 21-d trial and assigned randomly to the following 3 treatments: control (CON) group, LPS group, and LPS+IA group. The CON and LPS groups were provided with a basal diet, whereas the LPS+IA group received the basal diet supplemented with 0.6 mg/kg Macleaya cordata IA. Broilers in LPS and LPS+IA groups were intraperitoneally injected with LPS (1 mg/kg body weight) at 17, 19, and 21 days of age, while those in CON group were injected with equivalent amount of saline solution. RESULTS Results showed LPS injection caused systemic and liver inflammation in broilers, inhibited immune function, and ultimately lead to liver injury. By contrast, supplementation of IA ameliorated LPS-induced adverse change in serum parameters, boosted immunity in LPS+IA group. Furthermore, IA suppressed the elevation of hepatic inflammatory cytokines and caspases levels induced by LPS, as well as the expressions of genes related to the tolllike receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factorkappa B (NF-κB) pathway. CONCLUSION Dietary inclusion of 0.6 mg/kg Macleaya cordata IA could enhance immune function of body and inhibit liver damage via inactivating TLR4/MyD88/NF-κB signaling pathway in broilers.
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Affiliation(s)
- Jiaxin Chen
- Department of Animal Science, Qingdao Agricultural University, Qingdao 266109,
China
| | - Weiren Yang
- Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai’an 271018,
China
| | - Hua Liu
- College of Animal Science and Technology, Hunan Agriculture University, Changsha 410128,
China
| | - Jiaxing Niu
- Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai’an 271018,
China
| | - Yang Liu
- Key Laboratory of Efficient Utilization of Non-grain Feed Resources (Co-construction by Ministry and Province), Ministry of Agriculture and Rural Affairs, Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Tai’an 271018,
China
| | - Qun Cheng
- Department of Animal Science, Qingdao Agricultural University, Qingdao 266109,
China
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Gomes MFP, de Moura EDOC, Cardoso NM, da Silva GA, Dos Santos ACC, de Souza FS, Estadella D, Lambertucci RH, Lago JHG, Medeiros A. Supplementation with okra combined or not with exercise training is able to protect the heart of animals with metabolic syndrome. Sci Rep 2023; 13:1468. [PMID: 36702820 PMCID: PMC9879946 DOI: 10.1038/s41598-023-28072-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 01/12/2023] [Indexed: 01/27/2023] Open
Abstract
The metabolic syndrome (MetS) is a clinical manifestation strongly associated with cardiovascular disease, the main cause of death worldwide. In view of this scenario, many therapeutic proposals have appeared in order to optimize the treatment of individuals with MetS, including the practice of exercise training (ET) and the consumption of okra (O). The aim of the present study was to evaluate the effect of O consumption and/or ET in animals with MetS. In all, 32 male Zucker rats (fa/fa) at 10 weeks old were randomly distributed into four groups of 8 animals each: MetS, MetS+O, MetS+ET and MetS+ET+O, and 8 lean Zucker rats (fa/ +) comprised the control group. Okra was administered by orogastric gavage 2x/day (morning and night, 100 mg/kg), 5 days/week, for 6 weeks. The ET was performed on a treadmill 1x/day (afternoon), 5 days/week, 60 min/day, in an intensity of 70% of maximal capacity, for the same days of O treatment. It was found that, O consumption alone was able to promote improved insulin sensitivity (MetS 93.93 ± 8.54 mg/dL vs. MetS+O 69.95 ± 18.7 mg/dL, p ≤ 0.05, d = 1.65, CI = 50.32 -89.58, triglyceride reduction (MetS 492.9 ± 97.8 mg/dL vs. MetS+O 334.9 ± 98.0 mg/dL, p ≤ 0.05, d = 1.61, CI = 193.2-398.7). In addition, it promoted a reduction in systolic blood pressure (MetS 149.0 ± 9.3 mmHg vs. MetS+O 132.0 ± 11.4 mmHg, p ≤ 0.05, d = 1.63, CI = 120-140), prevented an increase in cardiac collagen (MetS 12.60 ± 2.08% vs. MetS+O 7.52 ± 0.77%, p ≤ 0.05, d = 3.24, CI = 6.56-8.49). When associated with ET, the results were similar. Thus, we conclude that O consumption combined or not with aerobic ET can have a protective effect on the cardiac tissue of rats with MetS.
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Affiliation(s)
- Moisés Felipe Pereira Gomes
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil.
- Center for Applied Social Sciences and Health, Universidade Católica de Santos (Unisantos), Av. Conselheiro Nébias, 300, Vila Matias, Santos, SP, 11015-002, Brazil.
| | | | - Naiara Magalhães Cardoso
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil
| | - Graziele Aparecida da Silva
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil
| | - Ana Carolina Cardoso Dos Santos
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil
| | - Fernanda Samantha de Souza
- Institute of Environmental, Chemical and Pharmaceutical Sciences, Universidade Federal de São Paulo (UNIFESP), Rua Prof. Artur Riedel, n° 275, Eldorado, Diadema, SP, 09972-270, Brazil
| | - Débora Estadella
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil
| | - Rafael Herling Lambertucci
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil
| | - João Henrique Ghilardi Lago
- Center of Natural and Human Sciences, Universidade Federal Do ABC, Av. Dos Estados, 500, Bangú, Santo André, SP, 09210-580, Brazil
| | - Alessandra Medeiros
- Department of Bioscience, Universidade Federal de São Paulo (UNIFESP), R. Silva Jardim, 136 - Vila Matias, Santos, SP, 11015-020, Brazil
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Niu J, Wang Q, Jing C, Liu Y, Liu H, Jiao N, Huang L, Jiang S, Guan Q, Li Y, Yang W. Dietary Galla Chinensis tannic acid supplementation in the diets improves growth performance, immune function and liver health status of broiler chicken. Front Vet Sci 2022; 9:1024430. [PMID: 36311675 PMCID: PMC9614106 DOI: 10.3389/fvets.2022.1024430] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Accepted: 09/26/2022] [Indexed: 11/04/2022] Open
Abstract
This experiment was conducted to investigate the effects of Galla Chinensis tannic acid (TA) on growth performance, immune function, and liver health status in broilers. A total of 288 1-day-old Arbor Acres broiler chickens were randomly divided into two groups in a 42-days study. The two groups were a basal diet (CON group) and a basal diet supplemented with 300 mg/kg Galla Chinensis tannic acid (TA group). The results showed that the TA group had significantly decreased feed-to-gain ratio (F/G) throughout the experiment (P < 0.05). The levels of total protein, albumin, low density lipoprotein, high density lipoprotein, urea, total cholesterol, and glucose in the TA group were significantly higher than in the CON group (P < 0.05). In addition, the serum immunoglobulin G, immunoglobulin M, and complements (C3, C4) levels in the TA group were significantly higher than those in the CON group (P < 0.05). Compared with the CON group, the hepatic interleukin-6, interleukin-18, NLRs family pyrin domain containing 3 (NLRP3), caspase-1, and caspase-3 in the TA group were significantly decreased (P < 0.05). Besides, TA group had significantly lower mRNA expression levels of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor-kappa B (NF-κB), and NLRP3 in liver (P < 0.05). The TA group had significantly higher the mRNA expression levels of Bcl-2 than CON group in liver (P < 0.05). Moreover, TA group tended to decrease Bax/Bcl-2 ratio in liver (P < 0.10). To sum up, dietary supplemented with microencapsulated TA from Galla Chinensis had beneficial effects on growth performance, immune function, and liver health status in broilers. The protective role of TA from Galla Chinensis in liver health of broilers might be related to the inhibition of hepatic apoptosis and pyroptosis via inactivation of TLR4/MyD88/NF-κB signaling pathway.
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Affiliation(s)
- Jiaxing Niu
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Qinjin Wang
- Shandong Wonong Agro-tech Group Co., Ltd., Weifang, China
| | - Changwei Jing
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Yang Liu
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Hua Liu
- College of Animal Science and Technology, Hunan Agriculture University, Changsha, China
| | - Ning Jiao
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Libo Huang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Shuzhen Jiang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Qinglin Guan
- Shandong Landoff Biotechnology Co., Ltd., Taian, China
| | - Yang Li
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China,*Correspondence: Yang Li
| | - Weiren Yang
- Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, Department of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China,Weiren Yang
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Gilbert KM, Reisfeld B, Zurlinden TJ, Kreps MN, Erickson SW, Blossom SJ. Modeling toxicodynamic effects of trichloroethylene on liver in mouse model of autoimmune hepatitis. Toxicol Appl Pharmacol 2014; 279:284-293. [PMID: 25026505 PMCID: PMC4171219 DOI: 10.1016/j.taap.2014.07.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 06/27/2014] [Accepted: 07/06/2014] [Indexed: 01/01/2023]
Abstract
Chronic exposure to industrial solvent and water pollutant trichloroethylene (TCE) in female MRL+/+mice generates disease similar to human autoimmune hepatitis. The current study was initiated to investigate why TCE-induced autoimmunity targeted the liver. Compared to other tissues the liver has an unusually robust capacity for repair and regeneration. This investigation examined both time-dependent and dose-dependent effects of TCE on hepatoprotective and pro-inflammatory events in liver and macrophages from female MRL+/+mice. After a 12-week exposure to TCE in drinking water a dose-dependent decrease in macrophage production of IL-6 at both the transcriptional and protein level was observed. A longitudinal study similarly showed that TCE inhibited macrophage IL-6 production. In terms of the liver, TCE had little effect on expression of pro-inflammatory genes (Tnfa, Saa2 or Cscl1) until the end of the 40-week exposure. Instead, TCE suppressed hepatic expression of genes involved in IL-6 signaling (Il6r, gp130, and Egr1). Linear regression analysis confirmed liver histopathology in the TCE-treated mice correlated with decreased expression of Il6r. A toxicodynamic model was developed to estimate the effects of TCE on IL-6 signaling and liver pathology under different levels of exposure and rates of repair. This study underlined the importance of longitudinal studies in mechanistic evaluations of immuntoxicants. It showed that later-occurring liver pathology caused by TCE was associated with early suppression of hepatoprotection rather than an increase in conventional pro-inflammatory events. This information was used to create a novel toxicodynamic model of IL-6-mediated TCE-induced liver inflammation.
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Affiliation(s)
- Kathleen M Gilbert
- University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR 72202, USA.
| | | | | | - Meagan N Kreps
- University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR 72202, USA.
| | - Stephen W Erickson
- University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR 72202, USA.
| | - Sarah J Blossom
- University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, AR 72202, USA.
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Othman MS, Aref AM, Mohamed AA, Ibrahim WA. Serum Levels of Interleukin-6 and Interleukin-10 as Biomarkers for Hepatocellular Carcinoma in Egyptian Patients. ISRN HEPATOLOGY 2013; 2013:412317. [PMID: 27335826 PMCID: PMC4890868 DOI: 10.1155/2013/412317] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 08/12/2013] [Indexed: 02/07/2023]
Abstract
Interleukin-10 (IL-10) and interleukin-6 (IL-6) have been reported to be related to hepatocellular carcinoma (HCC) prognosis. This study aimed to investigate the clinical usefulness of serum levels of IL-6 and IL-10 as biomarkers for HCC among high-risk patients. Materials and Methods. 80 individuals were enrolled in this study; they were categorized into 4 groups: group 1 healthy individuals (NC) (n = 20), group 2 chronic hepatitis C virus (HCV) patients (n = 20), group 3 cirrhotic patients (LC) (n = 20), and HCC group (n = 20). Using ELISA technique serum levels of IL-6, IL-10, and alpha fetoprotein (AFP) were evaluated in all groups. Results. The mean serum levels of IL-6 were significantly higher in HCC than in LC, HCV, and NC groups (13.99 ± 1.80, 7.49 ± 0.43, 5.78 ± 0.74, and 2.57 ± 0.31), respectively (P < 0.05); also the serum levels of IL-10 were significantly higher in HCC compared with LC, HCV, and NC groups (13.69 ± 1.89, 7.37 ± 0.53, 5.18 ± 0.6, and 3.31 ± 0.42) (P < 0.05). We also found that the tumor size is correlated strongly with IL-6 and IL-10 levels (r = 0.925, P < 0.001; r = 0.821, P < 0.001), respectively. Conclusion. The combination of those markers may help to identify a group of HCC patients with low AFP.
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Affiliation(s)
- Mohamed S. Othman
- Biochemistry Department, Faculty of Pharmacy, October University for Modern Sciences and Arts (MSA), Giza 11787, Egypt
| | - Ahmed M. Aref
- Biology Department, Faculty of Dentistry, October University for Modern Sciences and Arts (MSA), Giza 11787, Egypt
| | - Amal A. Mohamed
- Biochemsitry Department, National Hepatology and Tropical Medicine Research Institute, Fom El-Khalig, Cairo 11796, Egypt
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Ohlsson C, Mohan S, Sjögren K, Tivesten A, Isgaard J, Isaksson O, Jansson JO, Svensson J. The role of liver-derived insulin-like growth factor-I. Endocr Rev 2009; 30:494-535. [PMID: 19589948 PMCID: PMC2759708 DOI: 10.1210/er.2009-0010] [Citation(s) in RCA: 291] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
IGF-I is expressed in virtually every tissue of the body, but with much higher expression in the liver than in any other tissue. Studies using mice with liver-specific IGF-I knockout have demonstrated that liver-derived IGF-I, constituting a major part of circulating IGF-I, is an important endocrine factor involved in a variety of physiological and pathological processes. Detailed studies comparing the impact of liver-derived IGF-I and local bone-derived IGF-I demonstrate that both sources of IGF-I can stimulate longitudinal bone growth. We propose here that liver-derived circulating IGF-I and local bone-derived IGF-I to some extent have overlapping growth-promoting effects and might have the capacity to replace each other (= redundancy) in the maintenance of normal longitudinal bone growth. Importantly, and in contrast to the regulation of longitudinal bone growth, locally derived IGF-I cannot replace (= lack of redundancy) liver-derived IGF-I for the regulation of a large number of other parameters including GH secretion, cortical bone mass, kidney size, prostate size, peripheral vascular resistance, spatial memory, sodium retention, insulin sensitivity, liver size, sexually dimorphic liver functions, and progression of some tumors. It is clear that a major role of liver-derived IGF-I is to regulate GH secretion and that some, but not all, of the phenotypes in the liver-specific IGF-I knockout mice are indirect, mediated via the elevated GH levels. All of the described multiple endocrine effects of liver-derived IGF-I should be considered in the development of possible novel treatment strategies aimed at increasing or reducing endocrine IGF-I activity.
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Affiliation(s)
- Claes Ohlsson
- Division of Endocrinology, Institute of Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
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Abstract
Derangements in whole body glucose and lipid metabolism, accompanied by insulin resistance, are key features of obesity and the metabolic syndrome. A role for inflammation as a causative factor is an emerging concept in the field of metabolic disease. Research has centred on identifying important inflammatory markers, and tumour necrosis factor-alpha has been highlighted as a key mediator of insulin resistance, as well as interleukin-6 (IL-6). A parallel ongoing endeavour is the unravelling of molecular mechanisms underlying the beneficial effects of physical exercise on whole body glucose and lipid metabolism. Release of IL-6 from the contracting skeletal muscle has been proposed to be one of the molecular signals promoting the beneficial exercise-induced effects. These two opposing views of IL-6 underscore that the role of IL-6 in whole body physiology is incompletely resolved. This review aims at summarizing the current data on mechanisms by which IL-6 may impact on glucose and lipid metabolism.
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Affiliation(s)
- S Glund
- Section of Integrative Physiology, Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
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Porta C, De Amici M, Quaglini S, Paglino C, Tagliani F, Boncimino A, Moratti R, Corazza GR. Circulating interleukin-6 as a tumor marker for hepatocellular carcinoma. Ann Oncol 2007; 19:353-8. [PMID: 17962206 DOI: 10.1093/annonc/mdm448] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND A large amount of evidence suggests a possible role of interleukin-6 (IL-6) in the pathogenesis of hepatocellular carcinoma (HCC). PATIENTS AND METHODS We studied both IL-6 and A(1)FP in patients with HCC, non-neoplastic liver disease or in healthy controls. RESULTS IL-6 titers were four-fold higher in cancer than in cirrhotic patients and 25-fold higher than in healthy controls. As for alpha1-fetoprotein (A(1)FP) titers, the highest levels were observed in cancer patients. Receiver operating characteristic (ROC) curves analysis demonstrated that IL-6 is significantly more discriminant than A(1)FP, with 'optimal' cut-off values of 7.9 pg/ml (sensitivity = 0.83, specificity = 0.83, efficiency = 0.83). The ROC curves used to distinguish HCC from cirrhotic patients only, showed higher discriminant power of IL-6 versus A(1)FP titers, with a new cut-off value of 12 pg/ml (sensitivity = 0.73, specificity = 0.87, efficiency = 0.8). Discriminant analysis on HCC and non-HCC subjects yielded sensitivity, specificity and efficiency rates of 77%, 93% and 88%, respectively. The overall efficiency of the two tests combined was 82%. CONCLUSIONS IL-6 could be considered a promising tumor marker for HCC. In particular, the diagnostic value of the test is significantly increased when combined with A(1)FP.
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Affiliation(s)
- C Porta
- Internal Medicine and Medical Oncology, Istituto di Ricovero e Cura a Carattere Scientifico San Matteo University Hospital Foundation, Pavia, Italy.
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Abstract
During liver regeneration after partial hepatectomy, normally quiescent hepatocytes undergo one or two rounds of replication to restore the liver mass by a process of compensatory hyperplasia. A large number of genes are involved in liver regeneration, but the essential circuitry required for the process may be categorized into three networks: cytokine, growth factor and metabolic. There is much redundancy within each network, and intricate interactions exist between them. Thus, loss of function from a single gene rarely leads to complete blockage of liver regeneration. The innate immune system plays an important role in the initiation of liver regeneration after partial hepatectomy, and new cytokines and receptors that participate in initiation mechanisms have been identified. Hepatocytes primed by these agents readily respond to growth factors and enter the cell cycle. Presumably, the increased metabolic demands placed on hepatocytes of the regenerating liver are linked to the machinery needed for hepatocyte replication, and may function as a sensor that calibrates the regenerative response according to body demands. In contrast to the regenerative process after partial hepatectomy, which is driven by the replication of existing hepatocytes, liver repopulation after acute liver failure depends on the differentiation of progenitor cells. Such cells are also present in chronic liver diseases, but their contribution to the production of hepatocytes in those conditions is unknown. Most of the new knowledge about the molecular and cellular mechanisms of liver regeneration is both conceptually important and directly relevant to clinical problems.
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Affiliation(s)
- Nelson Fausto
- Department of Pathology, University of Washington School of Medicine, Seattle, WA 98195-7470, USA.
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Wallenius K, Jansson JO, Wallenius V. The therapeutic potential of interleukin-6 in treating obesity. Expert Opin Biol Ther 2005; 3:1061-70. [PMID: 14519071 DOI: 10.1517/14712598.3.7.1061] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Interleukin (IL)-6 is a multifunctional immune-modulating cytokine that has been suggested to have important functions in glucose and lipid metabolism. It is secreted from adipose tissue during resting conditions and from muscle during strenuous exercise. Recently, the authors reported that mice deficient of IL-6 develop mature-onset obesity, which was reversed by IL-6 replacement. The IL-6-deficient mice had increased glucose levels and decreased glucose tolerance, and blood lipids were increased in females. Furthermore, it was found that intracerebroventricular (ICV) IL-6 treatment acutely increased energy expenditure in rats and led to loss of fat mass following prolonged treatment, without causing symptoms of sickness behaviour or increased levels of acute-phase reactants. Thus, these data indicate a role for IL-6 in the regulation of energy homeostasis in rodents. In humans, several single nucleotide polymorphisms in the IL-6 gene promoter are known, one of which (174 C) is associated with reduced IL-6 transcription as well as decreased basal metabolic rate and insulin sensitivity in healthy male subjects. Furthermore, it was found that IL-6 levels in cerebrospinal fluid in obese humans were inversely correlated with more severe obesity, suggesting that severe obesity is coupled to a relative central IL-6 deficiency. Taken together, these data suggest that endogenous IL-6 has antiobesity effects and, therefore, it is possible that low endogenous IL-6 production contributes to obesity in humans.
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Affiliation(s)
- Kristina Wallenius
- Research Center for Endocrinology and Metabolism (RCEM), Endocrine Division, Sahlgrenska University Hospital, Gröna Stråket 8, SE-413 45 Gothenburg, Sweden.
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11
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Argast GM, Campbell JS, Brooling JT, Fausto N. Epidermal growth factor receptor transactivation mediates tumor necrosis factor-induced hepatocyte replication. J Biol Chem 2004; 279:34530-6. [PMID: 15199050 DOI: 10.1074/jbc.m405703200] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Tumor necrosis factor (TNF) has multiple biological effects such as participating in inflammation, apoptosis, and cell proliferation, but the mechanisms of its effects on epithelial cell proliferation have not been examined in detail. At the early stages of liver regeneration, TNF functions as a priming agent for hepatocyte replication and increases the sensitivity of hepatocytes to growth factors such as transforming growth factor alpha (TGFalpha); however, the mechanisms by which TNF interacts with growth factors and enhances hepatocyte replication are not known. Using the AML-12 hepatocyte cell line, we show that TNF stimulates proliferation of these cells through transactivation of the epidermal growth factor receptor (EGFR). The transactivation mechanism involves the release of TGFalpha into the medium through activation of the metalloproteinase TNFalpha-converting enzyme (also known as ADAM 17). Binding of the ligand to EGFR initiates a mitogenic cascade through extracellular signal-regulated kinases 1 and 2 and the partial involvement of protein kinase B. TNF-induced release of TGFalpha and activation of EGFR signaling were inhibited by TNFalpha protease inhibitor-1, an agent that interferes with TNFalpha-converting enzyme activity. We suggest that TNF-induced transactivation of EGFR may provide an early signal for the entry of hepatocytes into the cell cycle and may integrate proliferative and survival pathways at the start of liver regeneration.
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Affiliation(s)
- Gretchen M Argast
- Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309, USA
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12
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Torbenson M, Yang SQ, Liu HZ, Huang J, Gage W, Diehl AM. STAT-3 overexpression and p21 up-regulation accompany impaired regeneration of fatty livers. THE AMERICAN JOURNAL OF PATHOLOGY 2002; 161:155-61. [PMID: 12107100 PMCID: PMC1850692 DOI: 10.1016/s0002-9440(10)64167-3] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fatty liver is an important cause of morbidity in humans and is linked to impaired liver regeneration after liver injury, but the mechanisms for impaired liver regeneration remain unknown. In the normal liver, the interleukin (IL)-6/STAT-3 pathway is thought to play a central role in regeneration because this pathway is disrupted in IL-6-deficient mice that exhibit impaired liver regeneration after 70% partial hepatectomy (PH). To determine whether inhibition of STAT-3 is involved in fatty liver-related mitoinhibition, regenerative induction of STAT-3 was compared in normal mice and leptin-deficient ob/ob mice that have fatty livers and markedly impaired liver regeneration after PH. In both groups, two waves of STAT-3 activation were observed, the first in endothelia and the second in hepatocytes. Before PH, a significantly higher percentage of ob/ob endothelial and hepatocyte nuclei expressed phosphorylated (activated) STAT-3. After PH, phospho-STAT-3 accumulated in liver nuclei of lean mice and this response was markedly exaggerated in ob/ob mice. Moreover, a striking inverse correlation was noted between hepatocyte nuclear accumulation of phospho-STAT-3 and DNA synthesis (as assessed by bromodeoxyuridine labeling), as well as cyclin D1 mRNA induction and protein expression. In contrast, STAT-3 activation was positively correlated with p21 protein expression in both groups of mice. Because these results link exaggerated STAT-3 activation with impaired hepatocyte proliferation, STAT-3 inhibition cannot be a growth-arrest mechanism in ob/ob fatty livers. Rather, hyperinduction of this factor may promote mitoinhibition by up-regulating mechanisms that impede cell cycle progression.
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Affiliation(s)
- Michael Torbenson
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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