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Anbari DM, Al-Harithy RN. Ghrelin intronic lncRNAs, lnc-GHRL-3:2 and lnc-GHRL-3:3, as novel biomarkers in type 2 diabetes mellitus. Arch Physiol Biochem 2023; 129:241-245. [PMID: 32921167 DOI: 10.1080/13813455.2020.1817095] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND We aim to identify circulating lncRNAs located in the region of the ghrelin (GHRL) gene that play a role in the development of T2DM. METHODS Bioinformatic tool was used to identify candidates GHRL-lncRNAs. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to compare the expression levels of selected lncRNAs on diabetic patients and non-diabetic controls.Receiver operating characteristic (ROC) curve analysis was performed to evaluate the discriminatory power of selected GHRL-lncRNAs. RESULTS The bioinformatic analysis predicted three antisense and eight sense-intronic GHRL- lncRNAs. Two differentially expressed GHRL-lncRNAs were detected in diabetic patients. The expression levels of lnc-GHRL-3:2, lnc-GHRL-3:3, and the GHRL mRNA were significantly (p ≤ .0001) lower in the diabetic patients. ROC analysis showed that the area under the curve (AUC) value was 0.93 for lnc-GHRL-3:2 and 0.90 for lnc-GHRL-3:3. CONCLUSION lnc-GHRL-3:2 and lnc-GHRL-3:3 are novel biomarkers and might play a regulatory role in T2DM pathogenesis.
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Affiliation(s)
- Dalia M Anbari
- Department of Biochemistry, King AbdulAziz University, Jeddah, Saudi Arabia
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Thom G, McIntosh A, Messow CM, Leslie WS, Barnes AC, Brosnahan N, McCombie L, Malkova D, Al-Mrabeh A, Zhyzhneuskaya S, Welsh P, Sattar N, Taylor R, Lean MEJ. Weight loss-induced increase in fasting ghrelin concentration is a predictor of weight regain: Evidence from the Diabetes Remission Clinical Trial (DiRECT). Diabetes Obes Metab 2021; 23:711-719. [PMID: 33289256 DOI: 10.1111/dom.14274] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 11/22/2020] [Accepted: 11/26/2020] [Indexed: 01/08/2023]
Abstract
AIM To investigate whether appetite-related hormones were predictors of weight regain in the Diabetes Remission Clinical Trial (DiRECT). MATERIALS AND METHODS DiRECT is a cluster-randomized clinical trial, designed to assess the effect of weight loss on type 2 diabetes remission. For this post hoc analysis, data were available for 253 (147 interventions, 106 controls) individuals with type 2 diabetes (age 53.6 ± 7.5 years, body mass index 34.7 ± 4.4 kg/m2 , 59% men). Intervention participants received a 24-month weight management programme, and controls remained on usual diabetes care. Fasting plasma concentrations of leptin, ghrelin, glucagon-like peptide-1 and peptide YY were measured at baseline, 12 months and 24 months in all participants, and at 5 months in a subset of participants in the intervention (n = 56) and control groups (n = 22). Potential predictors were examined using multivariable linear regression models. RESULTS The intervention group lost 14.3 ± 6.0% body weight at 5 months but regained weight over time, with weight losses of 10.0 ± 7.5% at 12 months and 7.6 ± 6.3% at 24 months. Weight loss in controls was 1.1 ± 3.7% and 2.1 ± 5.0% at 12 and 24 months, respectively. Body weight increased by 2.3% (95% confidence interval [CI] 0.4, 4.1; P = 0.019) between 12 and 24 months for every 1-ng/mL increase in ghrelin between baseline and 12 months, and weight regain between 12 and 24 months was increased by 1.1% (95% CI 0.2, 2.0; P = 0.023) body weight for every 1-ng/mL increase in ghrelin at 12 months. CONCLUSION The rise in ghrelin (but not any other measured hormone) during diet-induced weight loss was a predictor of weight regain during follow-up, and concentrations remained elevated over time, suggesting a small but significant compensatory drive to regain weight. Attenuating the effects of ghrelin may improve weight-loss maintenance.
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Affiliation(s)
- George Thom
- Human Nutrition, School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow, UK
| | - Alasdair McIntosh
- Robertson Centre for Biostatistics, Institute of Health and Wellbeing, University of Glasgow, Glasgow, UK
| | - Claudia-Martina Messow
- Robertson Centre for Biostatistics, Institute of Health and Wellbeing, University of Glasgow, Glasgow, UK
| | - Wilma S Leslie
- Human Nutrition, School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow, UK
| | - Alison C Barnes
- Human Nutrition Research Centre, Institute of Health and Society, Newcastle University, Newcastle upon Tyne, UK
| | - Naomi Brosnahan
- Human Nutrition, School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow, UK
| | - Louise McCombie
- Human Nutrition, School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow, UK
| | - Dalia Malkova
- Human Nutrition, School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow, UK
| | - Ahmad Al-Mrabeh
- Newcastle Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Sviatlana Zhyzhneuskaya
- Newcastle Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Paul Welsh
- Institute of Cardiovascular and Medical Science, University of Glasgow, Glasgow, UK
| | - Naveed Sattar
- Institute of Cardiovascular and Medical Science, University of Glasgow, Glasgow, UK
| | - Roy Taylor
- Newcastle Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK
| | - Michael E J Lean
- Human Nutrition, School of Medicine, Dentistry and Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow Royal Infirmary, Glasgow, UK
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Wang Y, An H, Liu T, Qin C, Sesaki H, Guo S, Radovick S, Hussain M, Maheshwari A, Wondisford FE, O'Rourke B, He L. Metformin Improves Mitochondrial Respiratory Activity through Activation of AMPK. Cell Rep 2020; 29:1511-1523.e5. [PMID: 31693892 PMCID: PMC6866677 DOI: 10.1016/j.celrep.2019.09.070] [Citation(s) in RCA: 221] [Impact Index Per Article: 55.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/11/2019] [Accepted: 09/23/2019] [Indexed: 12/25/2022] Open
Abstract
Impaired mitochondrial respiratory activity contributes to the development of insulin resistance in type 2 diabetes. Metformin, a first-line antidiabetic drug, functions mainly by improving patients’ hyperglycemia and insulin resistance. However, its mechanism of action is still not well understood. We show here that pharmacological metformin concentration increases mitochondrial respiration, membrane potential, and ATP levels in hepatocytes and a clinically relevant metformin dose increases liver mitochondrial density and complex 1 activity along with improved hyperglycemia in high-fat- diet (HFD)-fed mice. Metformin, functioning through 5′ AMP-activated protein kinase (AMPK), promotes mitochondrial fission to improve mitochondrial respiration and restore the mitochondrial life cycle. Furthermore, HFD-fed-mice with liver-specific knockout of AMPKα1/2 subunits exhibit higher blood glucose levels when treated with metformin. Our results demonstrate that activation of AMPK by metformin improves mitochondrial respiration and hyperglycemia in obesity. We also found that supra-pharmacological metformin concentrations reduce adenine nucleotides, resulting in the halt of mitochondrial respiration. These findings suggest a mechanism for metformin’s anti-tumor effects. The mechanism of metformin action still remains controversial, in particular on mitochondrial activity and the involvement of AMPK. Wang et al. show that pharmacological metformin concentration or dose improves mitochondrial respiration by increasing mitochondrial fission through AMPK-Mff signaling; in contrast, supra-pharmacological metformin concentrations reduce mitochondrial respiration through decreasing adenine nucleotide levels.
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Affiliation(s)
- Yu Wang
- Division of Neonatology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Hongying An
- Division of Metabolism, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Ting Liu
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Caolitao Qin
- Division of Metabolism, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Hiromi Sesaki
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Shaodong Guo
- Department of Nutrition and Food Science, Texas A&M University, TX 77843, USA
| | - Sally Radovick
- Departments of Pediatrics and Medicine, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
| | - Mehboob Hussain
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Akhil Maheshwari
- Division of Neonatology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Fredric E Wondisford
- Departments of Pediatrics and Medicine, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ 08901, USA
| | - Brian O'Rourke
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Ling He
- Division of Neonatology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; Division of Metabolism, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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Ghadge AA, Khaire AA. Leptin as a predictive marker for metabolic syndrome. Cytokine 2019; 121:154735. [DOI: 10.1016/j.cyto.2019.154735] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 03/16/2019] [Accepted: 05/24/2019] [Indexed: 02/07/2023]
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Rouquet T, Clément P, Gaigé S, Tardivel C, Roux J, Dallaporta M, Bariohay B, Troadec JD, Lebrun B. Acute oral metformin enhances satiation and activates brainstem nesfatinergic neurons. Obesity (Silver Spring) 2014; 22:2552-62. [PMID: 25236366 DOI: 10.1002/oby.20902] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Accepted: 08/18/2014] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The study was designed to determine metformin effects on meal pattern, gastric emptying, energy expenditure, and to identify metformin-sensitive neurons and their phenotype. METHODS This study was performed on C57BL/6J and obese/diabetic (db/db) mice. Metformin (300 mg/kg) was administered by oral gavage. Food intake, meal pattern, oxygen consumption (VO2 ), and carbon dioxide production (VCO2 ) were obtained using an Oxylet Physiocage System. Gastric emptying assay and real-time RT-PCR from dorsal vagal complex extracts were also performed. C-Fos expression was used as a marker of neuronal activation. Phenotypic characterization of activated neurons was performed using either proopiomelanocortin (POMC)-Tau-Topaz GFP transgenic mice or NUCB2/nesfatin-1 and tyrosine hydroxylase (TH) labeling. RESULTS Acute per os metformin treatment slowed down gastric emptying, reduced meal size, but not meal number in a leptin-independent manner, and transiently decreased energy expenditure in a leptin-dependent manner. Metformin specifically activated central circuitry within the brainstem, independently of vagal afferents. Finally, while POMC neurons seemed sparsely activated, we report that a high proportion of the c-Fos positive cells were nesfatinergic neurons, some of which coexpressing TH. CONCLUSIONS Altogether, these results show that metformin modifies satiation by activating brainstem circuitry and suggest that NUCB2/nesfatin-1 could be involved in this metformin effect.
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Affiliation(s)
- Thaïs Rouquet
- EA 4674, Laboratoire de Physiologie et Physiopathologie du Système Nerveux Somato-Moteur et Neurovégétatif, FST St Jérôme, Aix-Marseille Université, Marseille, France; Biomeostasis CRO, FST St Jérôme, Marseille, France
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Gandini S, Puntoni M, Heckman-Stoddard BM, Dunn BK, Ford L, DeCensi A, Szabo E. Metformin and cancer risk and mortality: a systematic review and meta-analysis taking into account biases and confounders. Breast Cancer Res Treat 2014; 148:81-90. [PMID: 25253174 PMCID: PMC4196136 DOI: 10.1007/s10549-014-3141-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 09/17/2014] [Indexed: 12/16/2022]
Abstract
Treatment of diabetics with metformin is associated with decreased breast cancer risk in observational studies, but it remains unclear if this drug has clinical antineoplastic activity. In a recent presurgical trial, we found a heterogeneous effect of metformin on breast cancer proliferation (ki-67) depending upon insulin resistance (HOMA index). Here, we determined the associations of additional serum biomarkers of insulin resistance, tumor subtype, and drug concentration with ki-67 response to metformin. Two-hundred non-diabetic women were randomly allocated to metformin (850 mg/bid) or placebo for 4 weeks prior to breast cancer surgery. The ki-67 response to metformin was assessed comparing data obtained from baseline biopsy (ki-67 and tumor subtype) and serum markers (HOMA index, C-peptide, IGF-I, IGFBP-1, IGFBP-3, free IGF-I, hs-CRP, adiponectin) with the same measurements at definitive surgery. For patients with a blood sample taken within 24 h from last drug intake, metformin level was measured. Compared with placebo, metformin significantly decreased ki-67 in women with HOMA > 2.8, those in the lowest IGFBP-1 quintile, those in the highest IGFBP-3 quartile, those with low free IGF-I, those in the top hs-CRP tertile, and those with HER2-positive tumors. In women with HOMA index > 2.8, drug levels were positively correlated with the ki-67 decrease, whereas no trend was noted in women with HOMA < 2.8 (p-interaction = 0.07). At conventional antidiabetic doses, the effect of metformin on tumor ki-67 of non-diabetic breast cancer patients varies with host and tumor characteristics. These findings are relevant to design breast cancer prevention and treatment trials with metformin.
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Affiliation(s)
- Sara Gandini
- Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy
| | - Matteo Puntoni
- Clinical Trials Office, Office of the Scientific Director, E.O. Ospedali Galliera, Genoa, Italy
| | - Brandy M Heckman-Stoddard
- Breast and Gynecologic Cancer Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland
| | - Barbara K Dunn
- Chemopreventive Agent Development Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland
| | - Leslie Ford
- Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland
| | - Andrea DeCensi
- Division of Medical Oncology, E.O. Ospedali Galliera, Genoa, Italy
| | - Eva Szabo
- Lung and Upper Aerodigestive Cancer Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland.
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Gruzdeva O, Uchasova E, Belik E, Dyleva Y, Shurygina E, Barbarash O. Lipid, adipokine and ghrelin levels in myocardial infarction patients with insulin resistance. BMC Cardiovasc Disord 2014; 14:7. [PMID: 24433403 PMCID: PMC3898041 DOI: 10.1186/1471-2261-14-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 01/13/2014] [Indexed: 01/07/2023] Open
Abstract
Background Insulin resistance (IR) is a risk factor for ischaemic heart disease and myocardial infarction (MI). IR often manifests in MI and is regarded as an independent predictor of in-hospital mortality, which can provide early risk stratification for recurrent acute coronary events. Methods The study enrolled 200 patients (130 males and 70 females aged 61.4 ± 1.12 years) diagnosed with ST elevation MI. At days 1 and 12 from the MI onset, IR levels and lipid profiles, as well as serum glucose, insulin, adipokine and ghrelin levels, were measured. Results Free fatty acid (FFA) levels had the most pronounced changes: IR patients had a 9-fold increase in FFA levels at day 1, and patients without IR had a 6-fold increase. Leptin levels at days 1 and 12, in IR patients were, on average, 1.5- and 2-fold higher compared to the controls and patients with no IR (р < 0.05). Leptin levels in IR patients were increased throughout the entire hospital stay. Resistin levels in IR patients were, on average, 1.4-fold higher throughout the entire hospital stay, while in non-IR patients, resistin levels were similar to the controls. Adiponectin levels in IR patients were decreased compared to the controls, while in patients with IR, they were similar to the controls. Both IR and non-IR MI patients had 3-fold and 3.7-fold lower ghrelin levels at day 1, respectively, compared to the controls. The correlation analysis showed a negative correlation between ghrelin and FFA (r = −0.48 р = 0.007), ghrelin and leptin (r = −0.4 р = 0.003), ghrelin and insulin (r = −0.54 р = 0.002), and ghrelin and glucose (r = −0.31 р = 0.002) in MI patients. Conclusion Dyslipidaemia, along with insulinaemia and glycaemia, is one of the most significant IR risk factors in the acute and early recovery phases of MI. Dyslipidaemia is characterised by a high FFA level; an imbalance of leptin, resistin, and adiponectin; and a deficiency of ghrelin in the acute and early recovery periods of MI. FFA and ghrelin can be used as promising molecular markers to stratify the risk of recurrent acute coronary events and diabetes mellitus in MI patients.
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Affiliation(s)
| | - Evgenya Uchasova
- Research Institute for Complex Issues of Cardiovascular Diseases under the Siberian Branch of the Russian Academy of Medical Sciences, Kemerovo, Russia.
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Goebel-Stengel M, Hofmann T, Elbelt U, Teuffel P, Ahnis A, Kobelt P, Lambrecht NWG, Klapp BF, Stengel A. The ghrelin activating enzyme ghrelin-O-acyltransferase (GOAT) is present in human plasma and expressed dependent on body mass index. Peptides 2013; 43:13-9. [PMID: 23454172 DOI: 10.1016/j.peptides.2013.02.011] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 02/13/2013] [Accepted: 02/18/2013] [Indexed: 01/16/2023]
Abstract
Ghrelin is the only known peripherally produced and centrally acting peptide hormone stimulating food intake. The acylation of ghrelin is essential for binding to its receptor. Recently, the ghrelin activating enzyme ghrelin-O-acyltransferase (GOAT) was identified in mice, rats and humans. In addition to gastric mucosal expression, GOAT was also detected in the circulation of rodents and its expression was dependent on metabolic status. We investigated whether GOAT is also present in human plasma and whether expression levels are affected under different conditions of body weight. Normal weight, anorexic and obese subjects with body mass index (BMI) 30-40, 40-50 and >50 were recruited (n=9/group). In overnight fasted subjects GOAT protein expression was assessed by Western blot and ghrelin measured by ELISA. GOAT protein was detectable in human plasma. Anorexic patients showed reduced GOAT protein levels (-42%, p<0.01) whereas obese patients with BMI>50 had increased concentrations (+34%) compared to normal weight controls. Ghrelin levels were higher in anorexic patients compared to all other groups (+62-78%, p<0.001). Plasma GOAT protein expression showed a positive correlation with BMI (r=0.71, p<0.001) and a negative correlation with ghrelin (r=-0.60, p<0.001). Summarized, GOAT is also present in human plasma and GOAT protein levels depend on the metabolic environment with decreased levels in anorexic and increased levels in morbidly obese patients. These data may indicate that GOAT counteracts the adaptive changes of ghrelin observed under these conditions and ultimately contributes to the development or maintenance of anorexia and obesity as it is the only enzyme acylating ghrelin.
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Affiliation(s)
- Miriam Goebel-Stengel
- Department of Internal Medicine, Institute of Neurogastroenterology and Motility, Martin-Luther Hospital, Academic Teaching Institution of Charité-Universitätsmedizin Berlin, Berlin, Germany
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Schmid PM, Resch M, Schach C, Birner C, Riegger GA, Luchner A, Endemann DH. Antidiabetic treatment restores adiponectin serum levels and APPL1 expression, but does not improve adiponectin-induced vasodilation and endothelial dysfunction in Zucker diabetic fatty rats. Cardiovasc Diabetol 2013; 12:46. [PMID: 23497197 PMCID: PMC3606629 DOI: 10.1186/1475-2840-12-46] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 03/12/2013] [Indexed: 01/21/2023] Open
Abstract
Background Adiponectin is able to induce NO-dependent vasodilation in Zucker lean (ZL) rats, but this effect is clearly alleviated in their diabetic littermates, the Zucker diabetic fatty (ZDF) rats. ZDF rats also exhibit hypoadiponectinemia and a suppressed expression of APPL1, an adaptor protein of the adiponectin receptors, in mesenteric resistance arteries. Whether an antidiabetic treatment can restore the vasodilatory effect of adiponectin and improve endothelial function in diabetes mellitus type 2 is not known. Methods During our animal experiment from week 11 to 22 in each case seven ZDF rats received an antidiabetic treatment with either insulin (ZDF+I) or metformin (ZDF+M). Six normoglycemic ZL and six untreated ZDF rats served as controls. Blood glucose was measured at least weekly and serum adiponectin levels were quantified via ELISA in week 11 and 22. The direct vasodilatory response of their isolated mesenteric resistance arteries to adiponectin as well as the endothelium-dependent and -independent function was evaluated in a small vessel myograph. Additionally, the expression of different components of the adiponectin signaling pathway in the resistance arteries was quantified by real-time RT-PCR. Results In ZDF rats a sufficient blood glucose control could only be reached by treatment with insulin, but both treatments restored the serum levels of adiponectin and the expression of APPL1 in small resistance arteries. Nevertheless, both therapies were not able to improve the vasodilatory response to adiponectin as well as endothelial function in ZDF rats. Concurrently, a downregulation of the adiponectin receptors 1 and 2 as well as endothelial NO-synthase expression was detected in insulin-treated ZDF rats. Metformin-treated ZDF rats showed a reduced expression of adiponectin receptor 2. Conclusions An antidiabetic treatment with either insulin or metformin in ZDF rats inhibits the development of hypoadiponectinemia and downregulation of APPL1 in mesenteric resistance arteries, but is not able to improve adiponectin induced vasodilation and endothelial dysfunction. This is possibly due to alterations in the expression of adiponectin receptors and eNOS.
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Affiliation(s)
- Peter M Schmid
- Klinik und Poliklinik für Innere Medizin 2, Franz-Josef-Strauss Allee 11, University of Regensburg, Regensburg, 93042, Germany.
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Comparative effects of metformin and pioglitazone on omentin and leptin concentrations in patients with newly diagnosed diabetes: a randomized clinical trial. ACTA ACUST UNITED AC 2013; 182:1-6. [PMID: 23328000 DOI: 10.1016/j.regpep.2012.12.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 11/04/2012] [Accepted: 12/17/2012] [Indexed: 12/17/2022]
Abstract
AIMS To assess the effects of two commonly used oral hypoglycemic medications metformin and pioglitazone on serum concentrations of omentin and leptin in patients with newly diagnosed type 2 diabetes. METHODS In a clinical trial setting (NCT01593371), patients were randomly allocated to either metformin 1000mg daily (n=41), or pioglitazone 30mg daily (n=50). Serum concentrations of omentin and leptin were measured at baseline and after 12weeks. Patients' weight, waist circumference, blood pressure, fasting plasma glucose, fasting insulin, HbA1c, highly sensitive C-reactive protein, and serum lipids were also measured at the two visits. RESULTS Baseline concentrations of omentin and leptin were not different between the two arms of the trial. After three months, metformin decreased both omentin and leptin concentrations in women, and leptin concentrations only in men. On the other hand, pioglitazone reduced both adipokines only in women, but not men. Univariate and multivariate ANCOVA models revealed that both interventions are equally effective in reducing omentin concentration (p=0.497 for women and 0.344 for men in multivariate models controlling for the effects of confounding variables). Similarly, neither medication was more effective in reducing leptin concentrations after three months (p=0.822 for women and 0.441 for men in multivariate models). CONCLUSIONS Metformin and pioglitazone at pharmacologic doses are equally effective in alteration of serum omentin and leptin concentrations in patients with diabetes, albeit sex differences in response to medications exist. Implication of these findings on long term management and complication prevention of diabetes needs to be elucidated.
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Thondam SK, Cross A, Cuthbertson DJ, Wilding JP, Daousi C. Effects of chronic treatment with metformin on dipeptidyl peptidase-4 activity, glucagon-like peptide 1 and ghrelin in obese patients with Type 2 diabetes mellitus. Diabet Med 2012; 29:e205-10. [PMID: 22486277 DOI: 10.1111/j.1464-5491.2012.03675.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
AIMS Studies investigating the acute effects of metformin have demonstrated actions on the incretin system and appetite regulatory hormones. There are limited data to support that these effects are sustained in the long term. We therefore studied the effects of chronic treatment with metformin on endogenous glucagon-like peptide 1, dipeptidyl peptidase-4 activity and active ghrelin (an orexigenic hormone) in obese patients with Type 2 diabetes mellitus. METHODS Eight subjects [six male, age 58.7 ± 2.6 years, BMI 41.1 ± 2.9 kg/m(2) , HbA(1c) 69 ± 6 mmol/mol (8.5 ± 0.5%), mean ± sem] with drug-naïve Type 2 diabetes were studied for 6 h following a standard mixed meal, before and after at least 3 months of metformin monotherapy (mean dose 1.75 g daily). RESULTS The area under the curve (AUC(0-6 h) ) for active glucagon-like peptide 1 was significantly higher on metformin (pre-metformin 1750.8 ± 640 pmol l(-1) min(-1) vs. post-metformin 2718.8 ± 1182.3 pmol l(-1) min(-1) ; P=0.01). The areas under the curves for dipeptidyl peptidase-4 activity and ghrelin were not significantly different pre- and post-treatment with metformin. CONCLUSION Three months or more of metformin monotherapy in obese patients with Type 2 diabetes was associated with increased postprandial active glucagon-like peptide 1 levels. The effects of metformin on the enteroinsular axis may represent yet another important mechanism underlying its glucose-lowering effects.
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Affiliation(s)
- S K Thondam
- Diabetes and Endocrinology Clinical Research Group, University Hospital Aintree, Clinical Sciences Centre, Liverpool, UK.
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Stevanovic D, Janjetovic K, Misirkic M, Vucicevic L, Sumarac-Dumanovic M, Micic D, Starcevic V, Trajkovic V. Intracerebroventricular administration of metformin inhibits ghrelin-induced Hypothalamic AMP-kinase signalling and food intake. Neuroendocrinology 2012; 96:24-31. [PMID: 22343549 DOI: 10.1159/000333963] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 09/26/2011] [Indexed: 01/20/2023]
Abstract
BACKGROUND/AIMS The antihyperglycaemic drug metformin reduces food consumption through mechanisms that are not fully elucidated. The present study investigated the effects of intracerebroventricular administration of metformin on food intake and hypothalamic appetite-regulating signalling pathways induced by the orexigenic peptide ghrelin. METHODS Rats were injected intracerebroventricularly with ghrelin (5 µg), metformin (50, 100 or 200 µg), 5-amino-imidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR, 25 µg) and L-leucine (1 µg) in different combinations. Food intake was monitored during the next 4 h. Hypothalamic activation of AMP-activated protein kinase (AMPK), acetyl-CoA carboxylase (ACC), regulatory-associated protein of mTOR (Raptor), mammalian target of rapamycin (mTOR) and p70 S6 kinase 1 (S6K) after 1 h of treatment was analysed by immunoblotting. RESULTS Metformin suppressed the increase in food consumption induced by intracerebroventricular ghrelin in a dose-dependent manner. Ghrelin increased phosphorylation of hypothalamic AMPK and its targets ACC and Raptor, which was associated with the reduced phosphorylation of mTOR. The mTOR substrate, S6K, was activated by intracerebroventricular ghrelin despite the inhibition of mTOR. Metformin treatment blocked ghrelin-induced activation of hypothalamic AMPK/ACC/Raptor and restored mTOR activity without affecting S6K phosphorylation. Metformin also reduced food consumption induced by the AMPK activator AICAR while the ghrelin-triggered food intake was inhibited by the mTOR activator L-leucine. CONCLUSION Metformin could reduce food intake by preventing ghrelin-induced AMPK signalling and mTOR inhibition in the hypotalamus.
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Affiliation(s)
- Darko Stevanovic
- Institute of Medical Physiology, University of Belgrade, Belgrade, Serbia
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Katsiki N, Mikhailidis DP, Gotzamani-Psarrakou A, Didangelos TP, Yovos JG, Karamitsos DT. Effects of improving glycemic control with insulin on leptin, adiponectin, ghrelin and neuropeptidey levels in patients with type 2 diabetes mellitus: a pilot study. Open Cardiovasc Med J 2011; 5:136-47. [PMID: 21760856 PMCID: PMC3134985 DOI: 10.2174/1874192401105010136] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 05/30/2011] [Accepted: 05/31/2011] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVE Insulin therapy is associated with weight gain in patients with type 2 diabetes mellitus (T2DM). Several peptides are implicated in appetite control. We evaluated the effects of insulin-induced improved glycaemic control on leptin, adiponectin, ghrelin, neuropeptide Y (NPY) levels and patient characteristics. METHOD Consecutive T2DM patients (n = 90) were divided into 2 groups: Group A: 45 insulin-naïve uncontrolled (glycosylated haemoglobin A(1c); HbA(1c )>7%) patients on oral hypoglycaemic agents (OHAs) who converted to insulin monotherapy. Group B: 45 well-controlled (HbA(1c )<7%) patients on OHAs. Both groups were monitored at baseline, 3 and 6 months. Males and females were analyzed separately because some hormone levels differ between genders. RESULTS In both genders, insulin therapy (Group A) was associated with significant (p = 0.003 to <0.001) increases in weight, body mass index and leptin levels and significant decreases in glucose, HbA(1c) and NPY levels. In male insulin-treated patients a significant increase in adiponectin levels (p = 0.008) was observed. There were significant correlations (p = 0.016 to <0.001) between leptin levels, waist circumference and body fat in all patient groups, except group B males. CONCLUSION Changes in leptin, adiponectin and NPY levels may occur after insulin-induced improved glycaemic control. These changes may be influenced by gender, weight, body fat and HbA(1c).
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Affiliation(s)
- Niki Katsiki
- First Propedeutic Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Bouchoucha M, Uzzan B, Cohen R. Metformin and digestive disorders. DIABETES & METABOLISM 2011; 37:90-6. [DOI: 10.1016/j.diabet.2010.11.002] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2010] [Revised: 10/22/2010] [Accepted: 11/03/2010] [Indexed: 12/22/2022]
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Current world literature. Curr Opin Endocrinol Diabetes Obes 2011; 18:83-98. [PMID: 21178692 DOI: 10.1097/med.0b013e3283432fa7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Katsiki N, Mikhailidis DP, Gotzamani-Psarrakou A, Yovos JG, Karamitsos D. Effect of various treatments on leptin, adiponectin, ghrelin and neuropeptide Y in patients with type 2 diabetes mellitus. Expert Opin Ther Targets 2011; 15:401-20. [DOI: 10.1517/14728222.2011.553609] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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