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Casado ME, Canelles S, Arilla-Ferreiro E, Frago LM, Barrios V. Changes in Lipid Metabolism Enzymes in Rat Epididymal Fat after Chronic Central Leptin Infusion Are Related to Alterations in Inflammation and Insulin Signaling. Int J Mol Sci 2023; 24:ijms24087065. [PMID: 37108229 PMCID: PMC10138313 DOI: 10.3390/ijms24087065] [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: 02/14/2023] [Revised: 04/04/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
Leptin inhibits food intake and reduces the size of body fat depots, changing adipocyte sensitivity to insulin to restrain lipid accrual. This adipokine may modulate the production of cytokines that could diminish insulin sensitivity, particularly in visceral adipose tissue. To explore this possibility, we examined the effects of chronic central administration of leptin on the expression of key markers of lipid metabolism and its possible relationship with changes in inflammatory- and insulin-signaling pathways in epididymal adipose tissue. Circulating non-esterified fatty acids and pro- and anti-inflammatory cytokines were also measured. Fifteen male rats were divided into control (C), leptin (L, icv, 12 μg/day for 14 days), and pair-fed (PF) groups. We found a decrease in the activity of glucose-6-phosphate dehydrogenase and malic enzyme in the L group, with no changes in the expression of lipogenic enzymes. A reduction in the expression of lipoprotein lipase and carnitine palmitoyl-transferase-1A, together with a decrease in the phosphorylation of insulin-signaling targets and a low-grade inflammatory pattern, were detected in the epididymal fat of L rats. In conclusion, the decrease in insulin sensitivity and increased pro-inflammatory environment could regulate lipid metabolism, reducing epididymal fat stores in response to central leptin infusion.
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Affiliation(s)
- María E Casado
- Department of Endocrinology, Instituto de Investigación La Princesa, Hospital Infantil Universitario Niño Jesús, E-28009 Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029 Madrid, Spain
| | - Sandra Canelles
- Department of Endocrinology, Instituto de Investigación La Princesa, Hospital Infantil Universitario Niño Jesús, E-28009 Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029 Madrid, Spain
| | - Eduardo Arilla-Ferreiro
- Department of Biological Systems, Faculty of Medicine, Universidad de Alcalá, E-28871 Alcala de Henares, Spain
| | - Laura M Frago
- Department of Endocrinology, Instituto de Investigación La Princesa, Hospital Infantil Universitario Niño Jesús, E-28009 Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029 Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, E-28029 Madrid, Spain
| | - Vicente Barrios
- Department of Endocrinology, Instituto de Investigación La Princesa, Hospital Infantil Universitario Niño Jesús, E-28009 Madrid, Spain
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28029 Madrid, Spain
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Barrios V, Campillo-Calatayud A, Guerra-Cantera S, Canelles S, Martín-Rivada Á, Frago LM, Chowen JA, Argente J. Opposite Effects of Chronic Central Leptin Infusion on Activation of Insulin Signaling Pathways in Adipose Tissue and Liver Are Related to Changes in the Inflammatory Environment. Biomolecules 2021; 11:1734. [PMID: 34827732 PMCID: PMC8615824 DOI: 10.3390/biom11111734] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/13/2022] Open
Abstract
Leptin modulates insulin signaling and this involves the Akt pathway, which is influenced by changes in the inflammatory environment and with leptin regulating cytokine synthesis. We evaluated the association between activation of the insulin-signaling pathway and alterations in pro- and anti-inflammatory cytokine levels in inguinal fat and liver of chronic central leptin infused (L), pair-fed (PF), and control rats. Signal transducer and activator of transcription 3 (STAT3) phosphorylation was increased in inguinal fat and reduced in liver of L rats. Phosphorylation of c-Jun N-terminal kinase (JNK) and nuclear factor kappa B (NFkB) was increased in inguinal fat of L rats, together with a pro-inflammatory cytokine profile, while in the liver activation of JNK and NFkB were reduced and an anti-inflammatory pattern was found. Phosphorylation of the insulin receptor, Akt and mechanistic target of rapamycin was decreased in inguinal fat and increased in liver of L rats. There was a direct relationship between pSTAT3 and JNK and a negative correlation of Akt with pSTAT3 and JNK in both tissues. These results indicate that the effects of chronically increased leptin on insulin-related signaling are tissue-specific and suggest that inflammation plays a relevant role in the crosstalk between leptin and insulin signaling.
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Affiliation(s)
- Vicente Barrios
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28009 Madrid, Spain
| | - Ana Campillo-Calatayud
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
| | - Santiago Guerra-Cantera
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28009 Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, E-28029 Madrid, Spain
| | - Sandra Canelles
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28009 Madrid, Spain
| | - Álvaro Martín-Rivada
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, E-28029 Madrid, Spain
| | - Laura M. Frago
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28009 Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, E-28029 Madrid, Spain
| | - Julie A. Chowen
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28009 Madrid, Spain
- IMDEA Food Institute, CEI UAM + CSIC, E-28049 Madrid, Spain
| | - Jesús Argente
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación La Princesa, E-28009 Madrid, Spain; (A.C.-C.); (S.G.-C.); (S.C.); (Á.M.-R.); (L.M.F.); (J.A.C.)
- Centro de Investigación Biomédica en Red de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, E-28009 Madrid, Spain
- Department of Pediatrics, Faculty of Medicine, Universidad Autónoma de Madrid, E-28029 Madrid, Spain
- IMDEA Food Institute, CEI UAM + CSIC, E-28049 Madrid, Spain
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Packer M. Derangements in adrenergic-adipokine signalling establish a neurohormonal basis for obesity-related heart failure with a preserved ejection fraction. Eur J Heart Fail 2018; 20:873-878. [PMID: 29493068 DOI: 10.1002/ejhf.1167] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 01/17/2018] [Accepted: 01/30/2018] [Indexed: 12/18/2022] Open
Abstract
Among patients with heart failure and a preserved ejection (HFpEF), obesity is associated with a distinct phenotype that is characterized by adiposity-driven plasma volume expansion and cardiac overfilling, which is coupled with an impairment of ventricular distensibility. These pathophysiological abnormalities may be related to the increased actions of specific adipocyte-derived signalling molecules (aldosterone, neprilysin and leptin) that work in concert with increased renal sympathetic nerve traffic and activated beta2 -adrenergic receptors to promote sodium retention, microvascular rarefaction, cardiac fibrosis and systemic inflammation. This interplay leads to striking activation of the mineralocorticoid receptor, possibly explaining why obese patients with heart failure are most likely to benefit from spironolactone and eplerenone in large-scale clinical trials. Additionally, adipocytes express and release neprilysin, which (by degrading endogenous natriuretic peptides) can further promote plasma volume expansion and cardiac fibrosis. Heightened neprilysin activity may explain the low circulating levels of natriuretic peptides in obesity, the accelerated breakdown of natriuretic peptides in HFpEF, and the cardiac decompression following neprilysin inhibition in HFpEF patients who are obese. Furthermore, as adipose tissue accumulates and becomes dysfunctional, its secretion of leptin promotes renal sodium retention, microvascular changes and fibrotic processes in the heart, and systemic inflammation; these effects may be mediated or potentiated by the activation of beta2 -adrenergic receptors. These adrenergic-adipokine interactions provide a mechanistic framework for novel therapeutic strategies to alleviate the pathophysiological abnormalities of obesity-related HFpEF. Ongoing trials are well-positioned to test this hypothesis.
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Affiliation(s)
- Milton Packer
- Baylor Heart and Vascular Institute, Baylor University, Medical Center, Dallas, TX, USA
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Zhang L, Qin Y, Liang D, Li L, Liang Y, Chen L, Tong L, Zhou J, Li H, Zhang H. Association of polymorphisms in LEPR with type 2 diabetes and related metabolic traits in a Chinese population. Lipids Health Dis 2018; 17:2. [PMID: 29301582 PMCID: PMC5753482 DOI: 10.1186/s12944-017-0644-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 12/13/2017] [Indexed: 12/21/2022] Open
Abstract
Background Leptin acts as a mediator of inflammation and energy homeostasis by activating leptin receptor (LEPR). We conducted this study to explore the association of polymorphisms in LEPR with type 2 diabetes mellitus (T2DM) and its related metabolic traits. Methods We performed a case–control study to investigate the association of polymorphisms in LEPR with T2DM and related metabolic traits in a Chinese population, with a total of 922 T2DM patients and 1031 nondiabetic subjects. Polymorphisms were genotyped using MassARRAY assay. Results The G allele of rs1327118 was associated with a decreased risk of T2DM in men (P = 0.044, odds ratio = 0.707, 95% confidence interval = 0.504–0.991) and the G allele of rs3806318 was associated with increased systolic blood pressure (SBP) in men with T2DM. Besides, the women patients carrying the G allele of rs1327118 showed increased SBP and diastolic blood pressure (DBP) levels, but decreased high density lipoprotein cholesterol (HDL-C) level. Conclusion Our results suggest that rs1327118 may be associated with SBP, DBP and HDL-C levels in women with T2DM, and rs3806318 may be associated with T2DM and SBP level in men with T2DM. Further studies with larger sample size or functional experiments focused on exact mechanism are required to verify our observations.
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Affiliation(s)
- Lulu Zhang
- School of Public Health, Guangxi Medical University, Nanning, 530021, People's Republic of China.,Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Yingfen Qin
- Department of Endocrine, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Danyan Liang
- Third Affiliated Hospital of Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Li Li
- Department of Endocrine, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Yaojie Liang
- Beihai Center for Disease Prevention and Control, Beihai, 536000, People's Republic of China
| | - Lulin Chen
- School of Public Health, Guangxi Medical University, Nanning, 530021, People's Republic of China.,Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Lei Tong
- School of Public Health, Guangxi Medical University, Nanning, 530021, People's Republic of China.,Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Jia Zhou
- Department of Endocrine, First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, People's Republic of China
| | - Hong Li
- School of General Medicine, Guangxi Medical University, Nanning, 530021, People's Republic of China.
| | - Haiying Zhang
- School of Public Health, Guangxi Medical University, Nanning, 530021, People's Republic of China. .,Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases, Guangxi Medical University, Nanning, 530021, People's Republic of China. .,Guangxi key laboratory for genomic and personalized medicine, Guangxi collaborative innovation center for genomic and personalized medicine, Guangxi Medical University, Nanning, 530021, People's Republic of China.
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Pereira Braga C, Cavalcante Souza Vieira J, Lima Leite AD, Henrique Fernandes AA, Rabelo Buzalaf MA, Magalhães Padilha PD. Metalloproteomic and differential expression in plasma in a rat model of type 1 diabetes. Int J Biol Macromol 2017; 104:414-422. [DOI: 10.1016/j.ijbiomac.2017.06.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 05/01/2017] [Accepted: 06/06/2017] [Indexed: 11/28/2022]
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Paz-Filho G, Mastronardi CA, Licinio J. Leptin treatment: facts and expectations. Metabolism 2015; 64:146-56. [PMID: 25156686 DOI: 10.1016/j.metabol.2014.07.014] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/03/2014] [Accepted: 07/29/2014] [Indexed: 12/20/2022]
Abstract
Leptin has key roles in the regulation of energy balance, body weight, metabolism, and endocrine function. Leptin levels are undetectable or very low in patients with lipodystrophy, hypothalamic amenorrhea, and congenital leptin deficiency (CLD) due to mutations in the leptin gene. For these patients, leptin replacement therapy with metreleptin (a recombinant leptin analog) has improved or normalized most of their phenotypes, including normalization of endocrine axes, decrease in insulin resistance, and improvement of lipid profile and hepatic steatosis. Remarkable weight loss has been observed in patients with CLD. Due to its effects, leptin therapy has also been evaluated in conditions where leptin levels are normal or high, such as common obesity, diabetes (types 1 and 2), and Rabson-Mendenhall syndrome. A better understanding of the physiological roles of leptin may lead to the development of leptin-based therapies for other prevalent disorders such as obesity-associated nonalcoholic fatty liver disease, depression and dementia.
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Affiliation(s)
- Gilberto Paz-Filho
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia.
| | - Claudio A Mastronardi
- The John Curtin School of Medical Research, The Australian National University, Canberra, Australia.
| | - Julio Licinio
- South Australian Health and Medical Research Institute and Flinders University, Adelaide, Australia.
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Polyzos SA, Mantzoros CS. Leptin in health and disease: facts and expectations at its twentieth anniversary. Metabolism 2015; 64:5-12. [PMID: 25467841 DOI: 10.1016/j.metabol.2014.10.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 10/20/2014] [Accepted: 10/20/2014] [Indexed: 02/07/2023]
Affiliation(s)
- Stergios A Polyzos
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Christos S Mantzoros
- Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA; Boston VA Healthcare system and Division of Endocrinology, Diabetes and Metabolism, Department of Internal Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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Tomas Ž, Petranović MZ, Škarić-Jurić T, Barešić A, Salihović MP, Narančić NS. Novel locus for fibrinogen in 3' region of LEPR gene in island population of Vis (Croatia). J Hum Genet 2014; 59:623-9. [PMID: 25296580 DOI: 10.1038/jhg.2014.82] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 08/18/2014] [Accepted: 09/02/2014] [Indexed: 11/09/2022]
Abstract
Leptin, a possible mediator between energy homeostasis, inflammation and cardiovascular disease (CVD), acts via leptin receptors. We investigated association of single-nucleotide polymorphisms (SNPs) and haplotypes of the leptin receptor gene (LEPR) with several CVD risk factors: body mass index, waist circumference (WC), serum lipids, fibrinogen and C-reactive protein levels. Thirty-one SNPs in and near LEPR gene were analyzed in 986 inhabitants of the island of Vis, Croatia and 29 SNPs in the inland sample (N=499). We assessed linkage disequilibrium (LD), SNP and haplotype associations with the selected phenotypes. rs4291477 significantly associated with fibrinogen (P=0.003) and rs7539471 marginally significantly with high-density lipoprotein (P=0.004), but only in the Vis sample, while rs10493384 marginally significantly associated with triglyceride levels (P=0.006) in the inland sample. SNPs were grouped into eight LD blocks in Vis and in seven blocks in the inland population. Haplotype A-C-A-A-G-A in block 5 in Vis (rs1782754, rs1171269, rs1022981, rs6673324, rs3790426, rs10493380) and haplotype A-A-A-A in block 4 in the inland data (rs1782754, rs1022981, rs6673324, rs1137100) were nominally associated with WC, P=7.085 × 10(-22) (adjusted P=0.0979) and P=5.496 × 10(-144) (adjusted P=0.1062), respectively.
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Affiliation(s)
- Željka Tomas
- Institute for Anthropological Research, Gajeva 32, Zagreb, Croatia
| | | | | | - Ana Barešić
- Institute for Anthropological Research, Gajeva 32, Zagreb, Croatia
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Hulsmans M, Geeraert B, Arnould T, Tsatsanis C, Holvoet P. PPAR agonist-induced reduction of Mcp1 in atherosclerotic plaques of obese, insulin-resistant mice depends on adiponectin-induced Irak3 expression. PLoS One 2013; 8:e62253. [PMID: 23620818 PMCID: PMC3631170 DOI: 10.1371/journal.pone.0062253] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 03/19/2013] [Indexed: 11/18/2022] Open
Abstract
Synthetic peroxisome proliferator-activated receptor (PPAR) agonists are used to treat dyslipidemia and insulin resistance. In this study, we examined molecular mechanisms that explain differential effects of a PPARα agonist (fenofibrate) and a PPARγ agonist (rosiglitazone) on macrophages during obesity-induced atherogenesis. Twelve-week-old mice with combined leptin and LDL-receptor deficiency (DKO) were treated with fenofibrate, rosiglitazone or placebo for 12 weeks. Only rosiglitazone improved adipocyte function, restored insulin sensitivity, and inhibited atherosclerosis by decreasing lipid-loaded macrophages. In addition, it increased interleukin-1 receptor-associated kinase-3 (Irak3) and decreased monocyte chemoattractant protein-1 (Mcp1) expressions, indicative of a switch from M1 to M2 macrophages. The differences between fenofibrate and rosiglitazone were independent of Pparγ expression. In bone marrow-derived macrophages (BMDM), we identified the rosiglitazone-associated increase in adiponectin as cause of the increase in Irak3. Interestingly, the deletion of Irak3 in BMDM (IRAK3−/− BMDM) resulted in activation of the canonical NFκB signaling pathway and increased Mcp1 protein secretion. Rosiglitazone could not decrease the elevated Mcp1 secretion in IRAK3−/− BMDM directly and fenofibrate even increased the secretion, possibly due to increased mitochondrial reactive oxygen species production. Furthermore, aortic extracts of high-fat insulin-resistant LDL-receptor deficient mice, with lower adiponectin and Irak3 and higher Mcp1, showed accelerated atherosclerosis. In aggregate, our results emphasize an interaction between PPAR agonist-mediated increase in adiponectin and macrophage-associated Irak3 in the protection against atherosclerosis by PPAR agonists.
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Affiliation(s)
- Maarten Hulsmans
- Atherosclerosis and Metabolism Unit, Department of Cardiovascular Sciences, KU Leuven, Leuven, Belgium
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Muneyuki T, Nakajima K, Aoki A, Yoshida M, Fuchigami H, Munakata H, Ishikawa SE, Sugawara H, Kawakami M, Momomura SI, Kakei M. Latent associations of low serum amylase with decreased plasma insulin levels and insulin resistance in asymptomatic middle-aged adults. Cardiovasc Diabetol 2012; 11:80. [PMID: 22748134 PMCID: PMC3439247 DOI: 10.1186/1475-2840-11-80] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 06/15/2012] [Indexed: 12/16/2022] Open
Abstract
Background Low serum amylase is likely to be associated with obesity and metabolic abnormalities, which are often accompanied by impaired insulin action. However, it is unclear whether low serum amylase is associated with impaired insulin action in clinical settings. Therefore, we investigated the associations of low serum amylase with plasma insulin levels, and obesity-related parameters, including leptin. Research design and methods We measured serum amylase, plasma insulin, obesity-related parameters such as leptin, cardiometabolic risk factors, and anthropometric parameters in a cross-sectional study of 54 asymptomatic subjects (mean age 48.6 ± 7.6 years) who were not being treated for diabetes. Results Body mass index (BMI) and plasma glucose at 120 min after a 75-g oral glucose tolerance test (OGTT) were significantly higher in subjects with low serum amylase (< 60 IU/l, n = 21) than in those with normal-to-high serum amylase (n = 33) (P = 0.04 and P = 0.004, respectively). In univariate correlation analysis, serum amylase was significantly correlated with BMI alone (r = –0.39, P = 0.004). By contrast, multivariate logistic analysis showed that each 1-SD increase in quantitative insulin sensitivity check index, and each 1-SD decrease in plasma insulin OGTT at 0 and 60 min, homeostasis model assessment of insulin resistance (HOMA)-R, and HOMA-β were significantly associated with low serum amylase, particularly after adjusting for BMI. When subjects were divided into three groups according to HOMA-R, serum amylase levels were significantly lower in subjects with HOMA-R > 2.5 (n = 23) compared with subjects with HOMA-R 1.6–2.5 (n = 10) (61.1 ± 13.6 U/ml versus 76.9 ± 20.5 U/ml, Bonferroni test, P = 0.02), but not compared with subjects with HOMA-R<1.6 (n = 21; 62.7 ± 17.6 U/ml). Similar trends were observed when subjects were divided according to plasma leptin and fasting plasma insulin levels. Conclusions These results suggest that after adjusting for BMI, low serum amylase is associated with decreased basal insulin levels and insulin secretion, as well as high insulin resistance. The nature of these associations remains to be elucidated in further studies.
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Affiliation(s)
- Toshitaka Muneyuki
- First Department of Comprehensive Medicine, Saitama Medical Center, Jichi Medical University School of Medicine, 1-847 Amanuma, Omiya, Saitama 330-8503, Japan
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