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Momina SS, Gandla K. Flavonoid-Rich Trianthema decandra Ameliorates Cognitive Dysfunction in the Hyperglycemic Rats. Biochem Genet 2024:10.1007/s10528-024-10744-2. [PMID: 38570442 DOI: 10.1007/s10528-024-10744-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Accepted: 02/14/2024] [Indexed: 04/05/2024]
Abstract
The present study was aimed at the evaluation of neuroprotective ability of methanolic extract of Trianthema decandra (METD) against hyperglycemia-related cognitive impairment in rats. The extract of T. decandra was standardized by TLC and HPTLC methods. To verify the identity and purity of isolated compounds, they were segregated and characterized using various techniques, including UV-visible spectrophotometry, FT-IR, H-NMR, and Mass spectroscopy. α-Amylase and α-glucosidase inhibition property of the extracts were assessed in-vitro. The screening of the neuroprotective effects of METD in hyperglycemic rats was done utilizing Morri's water (MWM) and elevated plus maze (EPM) model, as well as acetylcholinesterase (AChE) activity. The extracts of Trianthema decandra and its chemical constituents, namely quercetin and phytol, demonstrated a significant protective effect on enzymes like α-amylase and α-glucosidase. Methanol and hydroalcoholic extracts have shown the strongest inhibitory activity followed by chloroform extract. Quercetin and phytol were associated with the methanolic and chloroform extracts which were identified using TLC and HPTLC techniques. During the thirty days of the study, the induction of diabetes in the rats exhibited persistent hyperglycemia, hyperlipidemia, higher escape latency during training trials and reduced time spent in target quadrant in probe trial in Morris water maze test, and increased escape latency in EPM task. Regimen of METD (200 and 400 mg/kg) in the diabetic rats reduced the glucose levels in blood, lipid, and liver profile and showed positive results on Morri's water and elevated plus maze tasks. During the investigation, it was determined that Trianthema decandra extracts and the chemical constituent's quercetin and phytol in it had anti-diabetic and neuroprotective activities.
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Affiliation(s)
- Sayyada Saleha Momina
- Department of Pharmacognosy and Phytochemistry, Chaitanya (Deemed to be University), Gandipet, HimayathNagar (Vill), Hyderabad, Telangana, 500075, India
| | - Kumaraswamy Gandla
- Department of Pharmacy, Chaitanya (Deemed to be University), Gandipet, HimayathNagar (Vill), Hyderabad, Telangana, 500075, India.
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2
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Shu Y, Yang X, Wei L, Wen C, Luo H, Qin T, Ma L, Liu Y, Wang B, Liu C, Zhou C. Akebia saponin D from Dipsacus asper wall. Ex C.B. Clarke ameliorates skeletal muscle insulin resistance through activation of IGF1R/AMPK signaling pathway. JOURNAL OF ETHNOPHARMACOLOGY 2024; 318:117049. [PMID: 37591362 DOI: 10.1016/j.jep.2023.117049] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/07/2023] [Accepted: 08/14/2023] [Indexed: 08/19/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Dipsacus asper Wall. Ex C.B. Clarke (DA), a perennial herb, is one of the most commonly used herbs in Traditional Chinese Medicine for strengthening muscles and bones and regulating blood vessels. Akebia saponin D (ASD/AVI) is a triterpenoid saponin extracted from the root of DA, which has favorable pharmacological properties such as anti-osteoporosis, anti-apoptosis, liver protection and hypolipidemic. AIM OF THE STUDY To explore the underlying mechanisms and regulatory role of Akebia saponin D (ASD/AVI) on high-fat diet-induced insulin resistance in skeletal muscle. MATERIALS AND METHODS C2C12 cells were used to explore the best concentration in the skeletal muscle insulin resistance model in an in vitro experiment. The protective effect of AVI on insulin resistance and the corresponding signaling pathway were detected by glucose content measurement, quantitative PCR, and Western blot. A high-fat diet STZ-induced insulin resistance mice model was used to evaluate the protective function of AVI in vivo. After four weeks of treatment, ITT, OGTT, and treadmill tests were applied to examine insulin sensitivity and their serum and skeletal muscle tissues were collected for further analysis. RESULTS AVI effectively reduced body weight, blood glucose levels and calorie intake in insulin-resistant mice, and reduced lipid accumulation and in their muscle tissue. AVI also improved glucose uptake and insulin sensitivity in both in vivo and in vitro experiments. Following AVI administration, there was an increase in the expression of the AMPK signaling pathway. Our experiments further confirmed that AVI specifically targets the IGF1R, thereby more effectively regulating the insulin signaling pathway. CONCLUSION AVI improves type 2 diabetes-induced insulin resistance in skeletal muscle by activating the IGF1R-AMPK signaling pathway, promoting glucose uptake and energy metabolism in IR.
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Affiliation(s)
- Yue Shu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Xinru Yang
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Linlin Wei
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Cailing Wen
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Hui Luo
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Tian Qin
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Liqing Ma
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China
| | - Ying Liu
- School of Pharmacy, Guangzhou Xinhua University, Guangzhou, 510520, China; School of Pharmacy, Macau University of Science and Technology, Taipa, Macau
| | - Bin Wang
- Department of Cardiovascular Ultrasound, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, 430071, China
| | - Cuiling Liu
- Department of Pharmacy, Shenzhen Bao'an Traditional Chinese Medicine Hospital, Shenzhen, 518101, China.
| | - Chun Zhou
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of Shock and Microcirculation, Southern Medical University, Guangzhou, 510515, China.
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Tian Y, Shi D, Liao H, Lu B, Pang Z. The role of Huidouba in regulating skeletal muscle metabolic disorders in prediabetic mice through AMPK/PGC-1α/PPARα pathway. Diabetol Metab Syndr 2023; 15:145. [PMID: 37391779 DOI: 10.1186/s13098-023-01097-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 05/23/2023] [Indexed: 07/02/2023] Open
Abstract
Prediabetes is a transitional state between normal blood glucose levels and diabetes, but it is also a reversible process. At the same time, as one of the most important tissues in the human body, the metabolic disorder of skeletal muscle is closely related to prediabetes. Huidouba (HDB) is a clinically proven traditional Chinese medicine with significant effects in regulating disorders of glucose and lipid metabolism. Our study aimed to investigate the efficacy and mechanism of HDB in prediabetic model mice from the perspective of skeletal muscle. C57BL/6J mice (6 weeks old) were fed a high-fat diet (HFD) for 12 weeks to replicate the prediabetic model. Three concentrations of HDB were treated with metformin as a positive control. After administration, fasting blood glucose was measured as an indicator of glucose metabolism, as well as lipid metabolism indicators such as total triglyceride (TG), low-density lipoprotein (LDL-C), high-density lipoprotein (HDL-C), free fatty acid (FFA), and lactate dehydrogenase (LDH). Muscle fat accumulation and glycogen accumulation were observed. The protein expression levels of p-AMPK, AMPK, PGC-1α, PPAR-α, and GLUT-4 were detected. After HDB treatment, fasting blood glucose was significantly improved, and TG, LDL-C, FFA, and LDH in serum and lipid accumulation in muscle tissue were significantly reduced. In addition, HDB significantly upregulated the expression levels of p-AMPK/AMPK, PGC-1α, PPAR-α, and GLUT-4 in muscle tissue. In conclusion, HDB can alleviate the symptoms of prediabetic model mice by promoting the AMPK/PGC-1α/PPARα pathway and upregulating the expression of GLUT-4 protein.
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Affiliation(s)
- Yu Tian
- School of Pharmacy, Minzu University of China, Beijing, PR China
- Key Laboratory of Ethnomedicine, Minzu University of China), Ministry of Education, Beijing, PR China
| | - Dongxu Shi
- School of Pharmacy, Minzu University of China, Beijing, PR China
- Key Laboratory of Ethnomedicine, Minzu University of China), Ministry of Education, Beijing, PR China
| | - Haiying Liao
- School of Pharmacy, Minzu University of China, Beijing, PR China
- Key Laboratory of Ethnomedicine, Minzu University of China), Ministry of Education, Beijing, PR China
| | - Binan Lu
- School of Pharmacy, Minzu University of China, Beijing, PR China.
- Key Laboratory of Ethnomedicine, Minzu University of China), Ministry of Education, Beijing, PR China.
| | - Zongran Pang
- School of Pharmacy, Minzu University of China, Beijing, PR China.
- Key Laboratory of Ethnomedicine, Minzu University of China), Ministry of Education, Beijing, PR China.
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Tagi VM, Mainieri F, Chiarelli F. Hypertension in Patients with Insulin Resistance: Etiopathogenesis and Management in Children. Int J Mol Sci 2022; 23:ijms23105814. [PMID: 35628624 PMCID: PMC9144705 DOI: 10.3390/ijms23105814] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/19/2022] [Accepted: 05/19/2022] [Indexed: 11/16/2022] Open
Abstract
Insulin resistance (IR) is a key component in the etiopathogenesis of hypertension (HS) in patients with diabetes mellitus (DM). Several pathways have been found to be involved in this mechanism in recent literature. For the above-mentioned reasons, treatment of HS should be specifically addressed in patients affected by DM. Two relevant recently published guidelines have stressed this concept, giving specific advice in the treatment of HS in children belonging to this group: the European Society of HS guidelines for the management of high blood pressure in children and adolescents and the American Academy of Pediatrics Clinical Practice Guideline for Screening and Management of High Blood Pressure in Children and Adolescents. Our aim is to summarize the main pathophysiological mechanisms through which IR causes HS and to highlight the specific principles of treatment of HS for children with DM.
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Mass recovery following caloric restriction reverses lipolysis and proteolysis, but not gluconeogenesis, in insulin resistant OLETF rats. PLoS One 2021; 16:e0252360. [PMID: 34727112 PMCID: PMC8562784 DOI: 10.1371/journal.pone.0252360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 10/18/2021] [Indexed: 11/19/2022] Open
Abstract
Caloric restriction (CR) is one of the most important behavioral interventions to reduce excessive abdominal adiposity, which is a risk factor for the development of insulin resistance. Previous metabolomics studies have characterized substrate metabolism during healthy conditions; however, the effects of CR and subsequent mass recovery on shifts in substrate metabolism during insulin resistance (IR) have not been widely investigated. To assess the effects of acute CR and the subsequent mass recovery on shifts in substrate metabolism, a cohort of 15-week old Long Evans Tokushima Otsuka (LETO) and Otsuka Long Evans Tokushima Fatty (OLETF) rats were calorie restricted (CR: 50% × 10 days) with or without partial body mass recovery (PR; 73% x 7 days), along with their respective ad libitum controls. End-of-study plasma samples were analyzed for primary carbon metabolites by gas chromatography (GC) time-of-flight (TOF) mass spectrometry (MS) data acquisition. Data analysis included PCA, Pearson correlation vs previously reported variables (adipose and body masses, and insulin resistance index, IRI), and metabolomics maps (MetaMapp) generated for the most significant group comparisons. All treatments elicited a significant group differentiation in at least one principal component. CR improved TCA cycle in OLETF, and increased lipolysis and proteolysis. These changes were reversed after PR except for gluconeogenesis. Plasma lipid concentrations were inversely correlated to IRI in LETO, but not OLETF. These shifts in substrate metabolism suggest that the CR-induced decreases in adipose may not be sufficient to more permanently alter substrate metabolism to improve IR status during metabolic syndrome.
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DI Giuseppe G, Ciccarelli G, Cefalo CM, Cinti F, Moffa S, Improta F, Capece U, Pontecorvi A, Giaccari A, Mezza T. Prediabetes: how pathophysiology drives potential intervention on a subclinical disease with feared clinical consequences. Minerva Endocrinol (Torino) 2021; 46:272-292. [PMID: 34218657 DOI: 10.23736/s2724-6507.21.03405-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder whose rising incidence suggests the epidemic proportions of the disease. Impaired Fasting Glucose (IFG) and Impaired Glucose Tolerance (IGT) - alone or combined - represent two intermediate metabolic condition between Normal Glucose Tolerance (NGT) and overt T2DM. Several studies have demonstrated that insulin resistance and beta-cell impairment can be identified even in normoglycemic prediabetic individuals. Worsening of these two conditions may lead to progression of IGT and/or IFG status to overt diabetes. Starting from these assumptions, it seems logical to suppose that interventions aimed at improving metabolic conditions, even in prediabetes, could represent an effective target to halt transition from IGT/IFG to manifest T2DM. Starting from pathophysiological knowledge, in this review we evaluate two possible interventions (lifestyle modifications and pharmacological agents) eligible as prediabetes therapy since they have been demonstrated to improve insulin resistance and beta-cell impairment. Detecting high-risk people and treating them could represent an effective strategy to slow down progression to overt diabetes, normalize glucose tolerance, and even prevent micro- and macrovascular complications.
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Affiliation(s)
- Gianfranco DI Giuseppe
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Gea Ciccarelli
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Chiara M Cefalo
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Francesca Cinti
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Simona Moffa
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Flavia Improta
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Umberto Capece
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Alfredo Pontecorvi
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Andrea Giaccari
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy.,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Teresa Mezza
- Endocrinologia e Diabetologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy - .,Dipartimento di Medicina e Chirurgia Traslazionale, Università Cattolica del Sacro Cuore, Rome, Italy
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7
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Lu J, Pang L, Zhang B, Gong Z, Song C. Silencing circANKRD36 inhibits streptozotocin-induced insulin resistance and inflammation in diabetic rats by targeting miR-145 via XBP1. Inflamm Res 2021; 70:695-704. [PMID: 33978765 DOI: 10.1007/s00011-021-01467-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/19/2021] [Accepted: 04/28/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Diabetes mellitus (DM) is defined as a group of metabolic diseases characterized by hyperglycemia, which results from a deficiency in insulin secretion and/or insulin action. In diabetic patients, type 2 diabetes mellitus (T2DM) is in the majority. We explored the effects of circANKRD36 on streptozotocin (STZ)-induced insulin resistance and inflammation in diabetic rats with the aim of uncovering the underlying mechanism. METHODS STZ was used to induce the in vivo T2DM rat model. After circANKRD36 interference, blood glucose, insulin and adiponectin were respectively detected. Hematoxylin and eosin (H&E), enzyme-linked immunosorbent assay (ELISA) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL) were conducted to examine inflammation and apoptosis in T2DM rats, and western blot was used for detecting apoptosis-related proteins. The binding relationships among circANKRD36, miR-145 and XBP1 were examined by luciferase reporter assay. RESULTS Results showed that circANKRD36 was expressed at a high level in T2DM rats, while silencing circANKRD36 led to decreased blood glucose and insulin, accompanied by increased adiponectin level, and ameliorating insulin resistance. Silencing circANKRD36 alleviated the inflammation and suppressed cell apoptosis in the pancreatic tissues of T2DM rats, which was abated by miR-145 inhibitor. The binding of miR-145 to XBP1 was then confirmed. Additionally, miR-145 inhibitor increased the level of XBP1 in T2DM rats, which was decreased in the presence of circANKRD36 silencing. CONCLUSION This study is the first to prove that silencing circANKRD36 inhibits STZ-induced insulin resistance and inflammation in diabetic rats by targeting miR- 145 via XBP1. The results warrant the importance of circRNAs as drug target and thereby pave way for the development of newer therapeutic measures for T2DM.
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MESH Headings
- Animals
- Cytokines/blood
- Diabetes Mellitus, Experimental/blood
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/immunology
- Diabetes Mellitus, Experimental/pathology
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/immunology
- Diabetes Mellitus, Type 2/pathology
- Inflammation/genetics
- Insulin Resistance/genetics
- Male
- MicroRNAs
- Pancreas/metabolism
- Pancreas/pathology
- RNA, Circular
- Rats, Sprague-Dawley
- Up-Regulation
- X-Box Binding Protein 1/genetics
- X-Box Binding Protein 1/metabolism
- Rats
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Affiliation(s)
- Jinger Lu
- Department of Endocrinology, The Affiliated People's Hospital of Ningbo University, Ningbo, 315040, Zhejiang, China
| | - Linrong Pang
- Department of Chemoradiotherapy Centre, The Affiliated People's Hospital of Ningbo University, Ningbo, 315040, Zhejiang, China
| | - Bo Zhang
- Department of Infectious Disease, The Affiliated People's Hospital of Ningbo University, Ningbo, 315040, Zhejiang, China
| | - Zhigang Gong
- College of Physical Education, Jiangxi Normal University, Nanchang, 330022, Jiangxi, China
| | - Chunhui Song
- College of Life Sciences, Jiangxi Normal University, No. 99 Ziyang Avenue, Nanchang, 330022, Jiangxi, China.
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Therapeutic Manipulation of Myocardial Metabolism: JACC State-of-the-Art Review. J Am Coll Cardiol 2021; 77:2022-2039. [PMID: 33888253 DOI: 10.1016/j.jacc.2021.02.057] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 02/16/2021] [Indexed: 12/26/2022]
Abstract
The mechanisms responsible for the positive and unexpected cardiovascular effects of sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonists in patients with type 2 diabetes remain to be defined. It is likely that some of the beneficial cardiac effects of these antidiabetic drugs are mediated, in part, by altered myocardial metabolism. Common cardiometabolic disorders, including the metabolic (insulin resistance) syndrome and type 2 diabetes, are associated with altered substrate utilization and energy transduction by the myocardium, predisposing to the development of heart disease. Thus, the failing heart is characterized by a substrate shift toward glycolysis and ketone oxidation in an attempt to meet the high energetic demand of the constantly contracting heart. This review examines the metabolic pathways and clinical implications of myocardial substrate utilization in the normal heart and in cardiometabolic disorders, and discusses mechanisms by which antidiabetic drugs and metabolic interventions improve cardiac function in the failing heart.
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Mirzay Razzaz J, Moameri H, Akbarzadeh Z, Ariya M, Hosseini SA, Ghaemi A, Osati S, Ehrampoush E, Homayounfar R. Investigating the relationship between insulin resistance and adipose tissue in a randomized Tehrani population. Horm Mol Biol Clin Investig 2021; 42:235-244. [PMID: 33711221 DOI: 10.1515/hmbci-2020-0084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 02/18/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Insulin resistance is the most common metabolic change associated with obesity. The present study aimed to investigate the relationship between insulin resistance and body composition especially adipose tissue in a randomized Tehrani population. METHODS This study used data of 2,160 individuals registered in a cross-sectional study on were randomly selected from among subjects who were referred to nutrition counseling clinic in Tehran, from April 2016 to September 2017. Insulin resistance was calculated by homeostasis model assessment formula. The odds ratio (95% CI) was calculated using logistic regression models. RESULTS The mean age of the men was 39 (±10) and women were 41 (±11) (the age ranged from 20 to 50 years). The risk of increased HOMA-IR was 1.03 (95% CI: 1.01-1.04) for an increase in one percent of Body fat, and 1.03 (95% CI: 1.00-1.05) for an increase in one percent of Trunk fat. Moreover, the odds ratio of FBS for an increase in one unit of Body fat percent and Trunk fat percent increased by 1.05 (adjusted odds ratio [95% CI: 1.03, 1.06]) and 1.05 (95% CI: 1.02, 1.08). Also, the risk of increased Fasting Insulin was 1.05 (95% CI: 1.03-1.07) for an increase in one unit of Body fat percent, and 1.05 (95% CI: 1.02-1.08) for an increase in one unit of Trunk fat percent. CONCLUSIONS The findings of the present study showed that there was a significant relationship between HOMA-IR, Fasting blood sugar, Fasting Insulin, and 2 h Insulin with percent of Body fat, percent of Trunk fat.
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Affiliation(s)
- Jalaledin Mirzay Razzaz
- National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hossein Moameri
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Zahra Akbarzadeh
- Department of Community Nutrition, School of Nutritional Sciences and Dietetics, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Mohammad Ariya
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran
| | - Seyed Ali Hosseini
- Students Research Committee, Fasa University of Medical Sciences, Fasa, Iran
| | - Alireza Ghaemi
- Department of Basic Sciences and Nutrition, Health Sciences Research Center, Addiction Institute, Faculty of Public Health, Mazandaran University of Medical Sciences, Sari, Iran
| | - Saeed Osati
- National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Elham Ehrampoush
- Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran.,Department of Nutrition, Fasa University of Medical Sciences, Fasa, Iran
| | - Reza Homayounfar
- National Nutrition and Food Technology Research Institute, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Noncommunicable Diseases Research Center, Fasa University of Medical Sciences, Fasa, Iran.,Department of Nutrition, Fasa University of Medical Sciences, Fasa, Iran
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Alismatis Rhizoma Triterpenes Alleviate High-Fat Diet-Induced Insulin Resistance in Skeletal Muscle of Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2021; 2021:8857687. [PMID: 33623531 PMCID: PMC7875633 DOI: 10.1155/2021/8857687] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 01/02/2021] [Accepted: 01/11/2021] [Indexed: 01/17/2023]
Abstract
Alismatis rhizoma (AR), which is the dried rhizome of Alisma orientale (Sam.) Juz. (Alismataceae), is an important component of many famous Chinese formulas for hypoglycemic. This study aimed to evaluate the insulin resistance (IR) alleviating effects of AR triterpenes (ART) and ART component compatibility (ARTC, the mixture of 16-oxo-alisol A, 16-oxo-alisol A 23-acetate, 16-oxo-alisol A 24-acetate, alisol C, alisol C 23-acetate, alisol L, alisol A, alisol A 23-acetate, alisol A 24-acetate, alisol L 23-acetate, alisol B, alisol B 23-acetate, 11-deoxy-alisol B and 11-deoxy-alisol B 23-acetate) in high-fat diet-induced IR mice and plamitate-treated IR C2C12 cells, respectively. A dose of 200 mg/kg of ART was orally administered to IR mice, and different doses (25, 50, and 100 μg/ml) of ARTC groups were treated to IR C2C12 cells. IPGTT, IPITT, body weight, Hb1AC, FFA, TNF-α, MCP-1, and IR-associated gene expression (p-AMPK, p-IRS-1, PI3K, p-AKT, p-JNK, and GLUT4) were measured in IR mice. Glucose uptake, TNF-α, MCP-1, and IR-associated gene expression were also measured in IR C2C12 cells. Results showed that ART alleviated high-fat diet-induced IR in the skeletal muscle of mice, and this finding was further validated by ARTC. This study demonstrated that ART presented a notable IR alleviating effect by regulating IR-associated gene expression, and triterpenes were the material basis for the IR alleviating activity of AR.
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11
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He Q, Bo J, Shen R, Li Y, Zhang Y, Zhang J, Yang J, Liu Y. S1P Signaling Pathways in Pathogenesis of Type 2 Diabetes. J Diabetes Res 2021; 2021:1341750. [PMID: 34751249 PMCID: PMC8571914 DOI: 10.1155/2021/1341750] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 12/24/2020] [Accepted: 01/04/2021] [Indexed: 02/06/2023] Open
Abstract
The pathogenesis of type 2 diabetes mellitus (T2DM) is very complicated. The currently well-accepted etiology is the "Ominous Octet" theory proposed by Professor Defronzo. Since presently used drugs for T2DM have limitations and harmful side effects, studies regarding alternative treatments are being conducted. Analyzing the pharmacological mechanism of biomolecules in view of pathogenesis is an effective way to assess new drugs. Sphingosine 1 phosphate (S1P), an endogenous lipid substance in the human body, has attracted increasing attention in the T2DM research field. This article reviews recent study updates of S1P, summarizing its effects on T2DM with respect to pathogenesis, promoting β cell proliferation and inhibiting apoptosis, reducing insulin resistance, protecting the liver and pancreas from lipotoxic damage, improving intestinal incretin effects, lowering basal glucagon levels, etc. With increasing research, S1P may help treat and prevent T2DM in the future.
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Affiliation(s)
- Qiong He
- Department of Endocrinology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Jiaqi Bo
- Department of Second Medical College, Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Ruihua Shen
- Department of Second Medical College, Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Yan Li
- Department of Second Medical College, Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Yi Zhang
- Department of Pharmacology, Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
- Key Laboratory of Cellular Physiology, Ministry of Education, Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Jiaxin Zhang
- Department of Endocrinology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Jing Yang
- Department of Endocrinology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Yunfeng Liu
- Department of Endocrinology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
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Sacramento JF, Martins FO, Rodrigues T, Matafome P, Ribeiro MJ, Olea E, Conde SV. A 2 Adenosine Receptors Mediate Whole-Body Insulin Sensitivity in a Prediabetes Animal Model: Primary Effects on Skeletal Muscle. Front Endocrinol (Lausanne) 2020; 11:262. [PMID: 32411098 PMCID: PMC7198774 DOI: 10.3389/fendo.2020.00262] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 04/08/2020] [Indexed: 12/20/2022] Open
Abstract
Epidemiological studies showed that chronic caffeine intake decreased the risk of type 2 diabetes. Previously, we described that chronic caffeine intake prevents and reverses insulin resistance induced by hypercaloric diets and aging, in rats. Caffeine has several cellular mechanisms of action, being the antagonism of adenosine receptors the only attained with human coffee consumption. Here, we investigated the subtypes of adenosine receptors involved on the effects of chronic caffeine intake on insulin sensitivity and the mechanisms and sex differences behind this effect. Experiments were performed in male and female Wistar rats fed either a chow or high-sucrose (HSu) diet (35% of sucrose in drinking water) during 28 days, to induce insulin resistance. In the last 15 days of diet the animals were submitted to DPCPX (A1 antagonist, 0.4 mg/kg), SCH58261 (A2A antagonist, 0.5 mg/kg), or MRS1754 (A2B antagonist, 9.5 μg/kg) administration. Insulin sensitivity, fasting glycaemia, blood pressure, catecholamines, and fat depots were assessed. Expression of A1, A2A, A2B adenosine receptors and protein involved in insulin signaling pathways were evaluated in the liver, skeletal muscle, and visceral adipose tissue. UCP1 expression was measured in adipose tissue. Paradoxically, SCH58261 and MRS1754 decreased insulin sensitivity in control animals, whereas they both improved insulin response in HSu diet animals. DPCPX did not alter significantly insulin sensitivity in control or HSu animals, but reversed the increase in total and visceral fat induced by the HSu diet. In skeletal muscle, A1, A2A, and A2B adenosine receptor expression were increased in HSu group, an effect that was restored by SCH58261 and MRS1754. In the liver, A1, A2A expression was increased in HSu group, while A2B expression was decreased, being this last effect reversed by administration of MRS1754. In adipose tissue, A1 and A2A block upregulated the expression of these receptors. A2 adenosine antagonists restored impaired insulin signaling in the skeletal muscle of HSu rats, but did not affect liver or adipose insulin signaling. Our results show that adenosine receptors exert opposite effects on insulin sensitivity, in control and insulin resistant states and strongly suggest that A2 adenosine receptors in the skeletal muscle are the majors responsible for whole-body insulin sensitivity.
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Affiliation(s)
- Joana F. Sacramento
- CEDOC, NOVA Medical School, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Fátima O. Martins
- CEDOC, NOVA Medical School, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Tiago Rodrigues
- Faculty of Medicine, Institute of Physiology and Institute of Clinical and Biomedical Investigation of Coimbra (iCBR), University of Coimbra, Coimbra, Portugal
| | - Paulo Matafome
- Faculty of Medicine, Institute of Physiology and Institute of Clinical and Biomedical Investigation of Coimbra (iCBR), University of Coimbra, Coimbra, Portugal
- Escola Superior de Tecnologia da Saúde, Departmento de Ciências Complementares, Instituto Politécnico de Coimbra, Coimbra, Portugal
| | - Maria J. Ribeiro
- CEDOC, NOVA Medical School, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisbon, Portugal
| | - Elena Olea
- Departamento de Bioquímica y Biología Molecular y Fisiología, Facultad de Medicina, CSIC, Ciber de Enfermedades Respiratorias, CIBERES, Instituto de Biología y Genética Molecular, Instituto de Salud Carlos III, Universidad de Valladolid, Valladolid, Spain
| | - Silvia V. Conde
- CEDOC, NOVA Medical School, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisbon, Portugal
- *Correspondence: Silvia V. Conde
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Di Pino A, DeFronzo RA. Insulin Resistance and Atherosclerosis: Implications for Insulin-Sensitizing Agents. Endocr Rev 2019; 40:1447-1467. [PMID: 31050706 PMCID: PMC7445419 DOI: 10.1210/er.2018-00141] [Citation(s) in RCA: 180] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/18/2018] [Indexed: 12/12/2022]
Abstract
Patients with type 2 diabetes mellitus (T2DM) are at high risk for macrovascular complications, which represent the major cause of mortality. Despite effective treatment of established cardiovascular (CV) risk factors (dyslipidemia, hypertension, procoagulant state), there remains a significant amount of unexplained CV risk. Insulin resistance is associated with a cluster of cardiometabolic risk factors known collectively as the insulin resistance (metabolic) syndrome (IRS). Considerable evidence, reviewed herein, suggests that insulin resistance and the IRS contribute to this unexplained CV risk in patients with T2DM. Accordingly, CV outcome trials with pioglitazone have demonstrated that this insulin-sensitizing thiazolidinedione reduces CV events in high-risk patients with T2DM. In this review the roles of insulin resistance and the IRS in the development of atherosclerotic CV disease and the impact of the insulin-sensitizing agents and of other antihyperglycemic medications on CV outcomes are discussed.
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Affiliation(s)
- Antonino Di Pino
- Diabetes Division, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, Texas
| | - Ralph A DeFronzo
- Diabetes Division, University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, Texas
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Brannick B, Wynn A, Dagogo-Jack S. Prediabetes as a toxic environment for the initiation of microvascular and macrovascular complications. Exp Biol Med (Maywood) 2017; 241:1323-31. [PMID: 27302176 DOI: 10.1177/1535370216654227] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Prediabetes is a state characterized by impaired fasting glucose or impaired glucose tolerance. Evidence is increasingly demonstrating that prediabetes is a toxic state, in addition to being a harbinger of future development of diabetes mellitus. This minireview discusses the pathophysiology and clinical significance of prediabetes, and approach to its management, in the context of the worldwide diabetes epidemic. The pathophysiologic defects underlying prediabetes include insulin resistance, β cell dysfunction, increased lipolysis, inflammation, suboptimal incretin effect, and possibly hepatic glucose overproduction. Recent studies have revealed that the long-term complications of diabetes may manifest in some people with prediabetes; these complications include classical microvascular and macrovascular disorders, and our discussion explores the role of glycemia in their development. Finally, landmark intervention studies in prediabetes, including lifestyle modification and pharmacologic treatment, are reviewed.
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Affiliation(s)
- Ben Brannick
- Division of Endocrinology, Diabetes and Metabolism, University of Tennessee Health Science Center, Memphis, Tennessee, TN 38163, USA
| | - Anne Wynn
- Division of Endocrinology, Diabetes and Metabolism, University of Tennessee Health Science Center, Memphis, Tennessee, TN 38163, USA
| | - Samuel Dagogo-Jack
- Division of Endocrinology, Diabetes and Metabolism, University of Tennessee Health Science Center, Memphis, Tennessee, TN 38163, USA
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Thakur S, Garg N, Zhang N, Hussey SE, Musi N, Adamo ML. IGF-1 receptor haploinsufficiency leads to age-dependent development of metabolic syndrome. Biochem Biophys Res Commun 2017; 486:937-944. [DOI: 10.1016/j.bbrc.2017.03.129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 03/23/2017] [Indexed: 01/02/2023]
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Gonzalez-Franquesa A, Patti ME. Insulin Resistance and Mitochondrial Dysfunction. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 982:465-520. [DOI: 10.1007/978-3-319-55330-6_25] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Adefegha SA, Oboh G, Adefegha OM. Ashanti pepper (Piper guineense Schumach et Thonn) attenuates carbohydrate hydrolyzing, blood pressure regulating and cholinergic enzymes in experimental type 2 diabetes rat model. J Basic Clin Physiol Pharmacol 2017; 28:19-30. [PMID: 27658140 DOI: 10.1515/jbcpp-2016-0001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 07/02/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Ashanti pepper (Piper guineense Schumach et Thonn) seed is well known in folkloric medicine in the management of type 2 diabetes (T2DM) with little or no scientific documentation for its action. This study investigated the effect of Ashanti pepper seed on some enzymes relevant to carbohydrate hydrolysis, blood regulation and the cholinergic system, as well as the blood glucose level, lipid profile, antioxidant parameters, and hepatic and renal function markers in T2DM rats. METHODS T2DM was induced by feeding rats with high-fat diet (HFD) for 14 days followed by a single intraperitoneal dose of 35 mg/kg body weight of streptozotocin (STZ). Three days after STZ induction, diabetic rats were placed on a dietary regimen containing 2%-4% Ashanti pepper. RESULTS Reduced blood glucose level with decreased α-amylase, α-glucosidase and angiotensin I converting enzyme (ACE) activities were observed in Ashanti pepper seed and acarbose-treated rat groups when compared to that of the diabetic control rat group. Furthermore, the results revealed that inclusion of 2%-4% Ashanti pepper seed in diabetic rat fed group diets may ameliorate the lipid profile, antioxidant status, and hepatic and renal function in T2DM rats as much as in the acarbose-treated groups. In addition, a chromatographic profile of the seed revealed the presence of quercitrin (116.51 mg/g), capsaicin (113.94 mg/g), dihydrocapsaicin (88.29 mg/g) and isoquercitrin (74.89 mg/g). CONCLUSIONS The results from this study clearly suggest that Ashanti pepper could serve as a promising source of phenolic compounds with great alternative therapeutic potentials in the management of T2DM.
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Gao Z, Zhang L, Xie W, Wang S, Bao X, Guo Y, Zhang H, Hu Q, Chen Y, Wang Z, Xue M, Jin G. Male Men1 heterozygous mice exhibit fasting hyperglycemia in the early stage of MEN1. J Endocrinol 2016; 230:347-55. [PMID: 27432891 DOI: 10.1530/joe-16-0090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Accepted: 07/18/2016] [Indexed: 01/29/2023]
Abstract
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited syndrome characterized by multiple tumors in the parathyroid glands, endocrine pancreas and anterior pituitary. Recent clinical studies have revealed a strong association between MEN1 syndrome and the risk of developing diabetes mellitus; however, the underlying mechanisms remain unknown. In this study, heterozygous Men1 knockout (Men1(+/-)) mice were used as MEN1 models to investigate MEN1-associated glucose metabolic phenotypes and mechanisms. Heterozygous deficiency of Men1 in 12-month-old male mice induced fasting hyperglycemia, along with increased serum insulin levels. However, male Men1(+/-) mice did not show insulin resistance, as evidenced by Akt activation in hepatic tissues and an insulin tolerance test. Increased glucose levels following pyruvate challenge and expression of key gluconeogenic genes suggested increased hepatic glucose output in the male Men1(+/-) mice. This effect could be partly due to higher basal serum glucagon levels, which resulted from pancreatic islet cell proliferation induced by heterozygous loss of Men1 Taken together, our results indicate that fasted male Men1(+/-) mice, in the early stage of development of MEN1, display glucose metabolic disorders. These disorders are caused not by direct induction of insulin resistance, but via increased glucagon secretion and the consequent stimulation of hepatic glucose production.
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Affiliation(s)
- Zhongxiuzi Gao
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Li Zhang
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Wenting Xie
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Siqi Wang
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Xiaorui Bao
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Yuli Guo
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Houjian Zhang
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Qingzhong Hu
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Yi Chen
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Zeen Wang
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Maoqiang Xue
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
| | - Guanghui Jin
- Department of Basic Medical SciencesMedical College, Xiamen University, Xiamen, China
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Sacramento J, Ribeiro M, Rodrigues T, Guarino M, Diogo L, Seiça R, Monteiro E, Matafome P, Conde S. Insulin resistance is associated with tissue-specific regulation of HIF-1α and HIF-2α during mild chronic intermittent hypoxia. Respir Physiol Neurobiol 2016; 228:30-8. [DOI: 10.1016/j.resp.2016.03.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 03/03/2016] [Accepted: 03/12/2016] [Indexed: 01/18/2023]
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20
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Fang Z, Li P, Jia W, Jiang T, Wang Z, Xiang Y. miR-696 plays a role in hepatic gluconeogenesis in ob/ob mice by targeting PGC-1α. Int J Mol Med 2016; 38:845-52. [DOI: 10.3892/ijmm.2016.2659] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 06/14/2016] [Indexed: 11/06/2022] Open
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Changes of insulin sensitivity and secretion after bariatric/metabolic surgery. Surg Obes Relat Dis 2016; 12:1199-205. [PMID: 27568471 DOI: 10.1016/j.soard.2016.05.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 05/11/2016] [Indexed: 02/06/2023]
Abstract
Type 2 diabetes (T2D) is classically characterized by failure of pancreatic β-cell function and insulin secretion to compensate for a prevailing level of insulin resistance, typically associated with visceral obesity. Although this is usually a chronic, progressive disease in which delay of end-organ complications is the primary therapeutic goal for medical and behavioral approaches, several types of bariatric surgery, especially those that include intestinal bypass components, exert powerful antidiabetes effects to yield remission of T2D in most cases. It has become increasingly clear that in addition to the known benefits of acute caloric restriction and chronic weight loss to ameliorate T2D, bariatric/metabolic operations also engage a variety of weight-independent mechanisms to improve glucose homeostasis, enhancing insulin sensitivity and secretion to varying degrees depending on the specific operation. In this paper, we review the effects of Roux-en-Y gastric bypass, biliopancreatic diversion, and vertical sleeve gastrectomy on the primary determinants of glucose homeostasis: insulin sensitivity, insulin secretion, and, to the lesser extent that it is known, insulin-independent glucose disposal. A full understanding of these effects should help optimize surgical and device-based designs to provide maximal antidiabetes impact, and it holds the promise to identify targets for possible novel diabetes pharmacotherapeutics. These insights also contribute to the conceptual rationale for use of bariatric operations as "metabolic surgery," employed primarily to treat T2D, including among patients not obese enough to qualify for surgery based on traditional criteria related to high body mass index.
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LEE WOOJUNG, YOON GOO, KIM MINCHEOL, KWON HAKCHEOL, BAE GYUUN, KIM YONGKEE, KIM SUNAM. 5,7-Dihydroxy-6-geranylflavanone improves insulin sensitivity through PPARα/γ dual activation. Int J Mol Med 2016; 37:1397-404. [DOI: 10.3892/ijmm.2016.2531] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2015] [Accepted: 03/04/2016] [Indexed: 11/06/2022] Open
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Abstract
Adenosine exerts a variety of physiological effects by binding to cell surface G-protein-coupled receptor subtypes, namely, A1, A2a, A2b, and A3. The central physiological role of adenosine is to preclude tissue injury and promote repair in response to stress. In the heart, adenosine acts as a cytoprotective modulator, linking cardiac function to metabolic demand predominantly via activation of adenosine A1 receptors (A1Rs), which leads to inhibition of adenylate cyclase activity, modulation of protein kinase C, and opening of ATP-sensitive potassium channels. Activation of myocardial adenosine A1Rs has been shown to modulate a variety of pathologies associated with ischemic cardiac injury, including arrhythmogenesis, coronary and ventricular dysfunction, apoptosis, mitochondrial dysfunction, and ventricular remodeling. Partial A1R agonists are agents that are likely to elicit favorable pharmacological responses in heart failure (HF) without giving rise to the undesirable cardiac and extra-cardiac effects observed with full A1R agonism. Preclinical data have shown that partial adenosine A1R agonists protect and improve cardiac function at doses that do not result in undesirable effects on heart rate, atrioventricular conduction, and blood pressure, suggesting that these compounds may constitute a valuable new therapy for chronic HF. Neladenoson bialanate (BAY1067197) is the first oral partial and highly selective A1R agonist that has entered clinical development for the treatment of HF. This review provides an overview of adenosine A1R-mediated signaling in the heart, summarizes the results from preclinical and clinical studies of partial A1R agonists in HF, and discusses the potential benefits of these drugs in the clinical setting.
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Park SE, Park CY, Sweeney G. Biomarkers of insulin sensitivity and insulin resistance: Past, present and future. Crit Rev Clin Lab Sci 2015; 52:180-90. [PMID: 26042993 DOI: 10.3109/10408363.2015.1023429] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Insulin resistance in insulin target tissues including liver, skeletal muscle and adipose tissue is an early step in the progression towards type 2 diabetes. Accurate diagnostic parameters reflective of insulin resistance are essential. Longstanding tests for fasting blood glucose and HbA1c are useful and although the hyperinsulinemic euglycemic clamp remains a "gold standard" for accurately determining insulin resistance, it cannot be implemented on a routine basis. The study of adipokines, and more recently myokines and hepatokines, as potential biomarkers for insulin sensitivity is now an attractive and relatively straightforward approach. This review discusses potential biomarkers including adiponectin, RBP4, chemerin, A-FABP, FGF21, fetuin-A, myostatin, IL-6, and irisin, all of which may play significant roles in determining insulin sensitivity. We also review potential future directions of new biological markers for measuring insulin resistance, including metabolomics and gut microbiome. Collectively, these approaches will provide clinicians with the tools for more accurate, and perhaps personalized, diagnosis of insulin resistance.
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Affiliation(s)
- Se Eun Park
- a Division of Endocrinology and Metabolism, Department of Internal Medicine , Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine , Seoul , South Korea and
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Lee W, Ham J, Kwon HC, Yoon G, Bae GU, Kim YK, Kim SN. Amorphastilbol exerts beneficial effects on glucose and lipid metabolism in mice consuming a high-fat-diet. Int J Mol Med 2015; 36:527-33. [PMID: 26035293 DOI: 10.3892/ijmm.2015.2227] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 05/21/2015] [Indexed: 11/06/2022] Open
Abstract
In the present study, the anti-diabetic effects of amorphastilbol (APH) from Amorpha fruticosa (AF) were evaluated in high-fat-diet (HFD) mice. HFD-induced blood glucose and insulin levels are significantly reduced in AF extract or APH treatment groups. HFD-induced weight gain was reduced by AF treatment, which is accompanied by reduction of fat mass and adipocyte size and number in white adipose tissues. Furthermore, total cholesterol and low-density lipoprotein-cholesterol levels are decreased in AF- or APH-treated mice. In addition, AF and APH are able to improve insulin sensitivity through inhibition of protein tyrosine phosphatase 1B, a negative regulator of the insulin-signaling pathway. Taken together, the data suggest that AF has beneficial effects on glucose and lipid metabolism and its pharmacological effects are driven, in part, by its active component, APH. Therefore, AF and APH can be used as potential therapeutic agents against type 2 diabetes and associated metabolic disorders, including obesity, by enhancing glucose and lipid metabolism.
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Affiliation(s)
- Woojung Lee
- Natural Medicine Center, KIST Gangneung Institute, Gangneung, Gangwon 210-340, Republic of Korea
| | - Jungyeob Ham
- Natural Medicine Center, KIST Gangneung Institute, Gangneung, Gangwon 210-340, Republic of Korea
| | - Hak Cheol Kwon
- Natural Medicine Center, KIST Gangneung Institute, Gangneung, Gangwon 210-340, Republic of Korea
| | - Goo Yoon
- College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Jeonnam 534-729, Republic of Korea
| | - Gyu-Un Bae
- Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women's University, Seoul 140-742, Republic of Korea
| | - Yong Kee Kim
- Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women's University, Seoul 140-742, Republic of Korea
| | - Su-Nam Kim
- Natural Medicine Center, KIST Gangneung Institute, Gangneung, Gangwon 210-340, Republic of Korea
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Coletta DK, Fernandez M, Cersosimo E, Gastaldelli A, Musi N, DeFronzo RA. The effect of muraglitazar on adiponectin signalling, mitochondrial function and fat oxidation genes in human skeletal muscle in vivo. Diabet Med 2015; 32:657-64. [PMID: 25484175 PMCID: PMC6824198 DOI: 10.1111/dme.12664] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/02/2014] [Indexed: 01/13/2023]
Abstract
AIMS The molecular mechanisms by which muraglitazar (peroxisome proliferator-activated receptor γ/α agonist) improves insulin sensitivity in Type 2 diabetes mellitus are not fully understood. We hypothesized that muraglitazar would increase expression of 5'-monophosphate-activated protein kinase and genes involved in adiponectin signalling, free fatty acid oxidation and mitochondrial function in skeletal muscle. METHODS Sixteen participants with Type 2 diabetes received muraglitazar, 5 mg/day (n = 12) or placebo (n = 4). Before and after 16 weeks, participants had vastus lateralis muscle biopsy followed by 180 min euglycaemic hyperinsulinaemic clamp. RESULTS Muraglitazar increased plasma adiponectin (9.0 ± 1.1 to 17.8 ± 1.5 μg/ml, P < 0.05), while no significant change was observed with placebo. After 16 weeks with muraglitazar, fasting plasma glucose declined by 31%, fasting plasma insulin decreased by 44%, insulin-stimulated glucose disposal increased by 81%, HbA1c decreased by 21% and plasma triglyceride decreased by 39% (all P < 0.05). Muraglitazar increased mRNA levels of 5'-monophosphate-activated protein kinase, adiponectin receptor 1, adiponectin receptor 2, peroxisome proliferator-activated receptor gamma coactivator-1 alpha and multiple genes involved in mitochondrial function and fat oxidation. In the placebo group, there were no significant changes in expression of these genes. CONCLUSIONS Muraglitazar increases plasma adiponectin, stimulates muscle 5'-monophosphate-activated protein kinase expression and increases expression of genes involved in adiponectin signalling, mitochondrial function and fat oxidation. These changes represent important cellular mechanisms by which dual peroxisome proliferator-activated receptor agonists improve skeletal muscle insulin sensitivity.
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Affiliation(s)
- D K Coletta
- Mayo Clinic in Arizona, Scottsdale; School of Life Sciences, Arizona State University, Tempe; Department of Basic Medical Sciences, University of Arizona College of Medicine - Phoenix
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Disclosing caffeine action on insulin sensitivity: effects on rat skeletal muscle. Eur J Pharm Sci 2015; 70:107-16. [PMID: 25661425 DOI: 10.1016/j.ejps.2015.01.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 01/16/2015] [Accepted: 01/26/2015] [Indexed: 01/12/2023]
Abstract
Caffeine, a non-selective adenosine antagonist, has distinct effects on insulin sensitivity when applied acutely or chronically. Herein, we investigated the involvement of adenosine receptors on insulin resistance induced by single-dose caffeine administration. Additionally, the mechanism behind adenosine receptor-mediated caffeine effects in skeletal muscle was assessed. The effect of the administration of caffeine, 8-cycle-1,3-dipropylxanthine (DPCPX, A1 antagonist), 2-(2-Furanyl)-7-(2-phenylethyl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine (SCH58261, A2A antagonist) and 8-(4-{[(4-cyanophenyl)carbamoylmethyl]-oxy}phenyl)-1,3-di(n-propyl)xanthine (MRS1754, A2B antagonist) on whole-body insulin sensitivity was tested. Skeletal muscle Glut4,5'-AMP activated protein kinase (AMPK) and adenosine receptor protein expression were also assessed. The effect of A1 and A2B adenosine agonists on skeletal muscle glucose uptake was evaluated in vitro. Sodium nitroprussiate (SNP, 10nM), a nitric oxide (NO) donor, was used to evaluate the effect of NO on insulin resistance induced by adenosine antagonists. Acute caffeine decreased insulin sensitivity in a concentration dependent manner (Emax=55.54±5.37%, IC50=11.61nM), an effect that was mediated by A1 and A2B adenosine receptors. Additionally, acute caffeine administration significantly decreased Glut4, but not AMPK expression, in skeletal muscle. We found that A1, but not A2B agonists increased glucose uptake in skeletal muscle. SNP partially reversed DPCPX and MRS1754 induced-insulin resistance. Our results suggest that insulin resistance induced by acute caffeine administration is mediated by A1 and A2B adenosine receptors. Both Glut4 and NO seem to be downstream effectors involved in insulin resistance induced by acute caffeine.
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Panag KMDS, Kaur N, Goyal G. Correlation of insulin resistance by various methods with fasting insulin in obese. Int J Appl Basic Med Res 2014; 4:S41-5. [PMID: 25298942 PMCID: PMC4181131 DOI: 10.4103/2229-516x.140733] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Accepted: 05/17/2014] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Several studies indicate that obesity is closely related to insulin resistance (IR). However, this relationship has not been adequately explored. AIMS This study aims to evaluate the prevalence of IR among obese using some indirect methods for assessment of IR. MATERIALS AND METHODS We analyzed the correlation of fasting insulin (FI) with body mass index. We examined 100 obese and overweight. Anthropometric measurements were done for all individuals. Blood lipids parameters, glucose, and insulin were assayed after a 10 h fast. The indices McAuley (McA), homeostasis model assessments (HOMA), quantitative insulin sensitivity check index (QUICKI) were used to assess IR. RESULTS In this study, the correlations of FI with McA, HOMA and QUICKI were significant (P < 0.05). FI test had significant sensitivity and specificity when compared with McA, HOMA and QUICKI indices. FI gives parallel results to the assessment of IR by other methods. Validity of FI was further analyzed by Cohen's kappa test and had a satisfactory agreement (χ =0.940). CONCLUSION Altogether, this study suggested that FI was sensitive and also specific as McA in assessment of IR in obese. Thus, FI can be used as an easy test to detect IR also in obese.
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Affiliation(s)
| | - Navneet Kaur
- Department of Biochemistry, G.G.S. Medical College, Faridkot, Punjab, India
| | - Gitanjali Goyal
- Department of Biochemistry, G.G.S. Medical College, Faridkot, Punjab, India
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Daniele G, Abdul-Ghani M, DeFronzo RA. What are the pharmacotherapy options for treating prediabetes? Expert Opin Pharmacother 2014; 15:2003-18. [PMID: 25139488 DOI: 10.1517/14656566.2014.944160] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
INTRODUCTION The incidence of type 2 diabetes mellitus (T2DM) has risen to epidemic proportions, and this is associated with enormous cost. T2DM is preceded by 'prediabetes', and the diagnosis of impaired glucose tolerance (IGT) and/or impaired fasting glucose (IFG) provides an opportunity for targeted intervention. Prediabetic subjects manifest both core defects characteristic of T2DM, that is, insulin resistance and β-cell dysfunction. Interventions which improve insulin sensitivity and/or preserve β-cell function are logical strategies to delay the conversion of IGT/IFG to T2DM or revert glucose tolerance to normal. AREAS COVERED The authors examine pharmacologic agents that have proven to decrease the conversion of IGT to T2DM and represent potential treatment options in prediabetes. EXPERT OPINION Weight loss improves whole body insulin sensitivity, preserves β-cell function and decreases progression of prediabetes to T2DM. In real life long-term weight loss is the exception and, even if successful, 40 - 50% of IGT individuals still progress to T2DM. Pharmacotherapy provides an alternative strategy to improve insulin sensitivity and preserve β-cell function. Thiazolidinediones (TZDs) are highly effective in T2DM prevention. Long-acting glucagon-like peptide-1 (GLP-1) analogs, because they augment β-cell function and promote weight loss, are effective in preventing IGT progression to T2DM. Metformin is considerably less effective than TZDs or GLP-1 analogs.
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Affiliation(s)
- Giuseppe Daniele
- University of Texas Health Science Center at San Antonio, Division of Diabetes , 7703 Floyd Curve Dr, San Antonio, TX, 78229 , USA +1 210 567 6691 ; +1 210 567 6554 ;
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DeFronzo RA, Triplitt CL, Abdul-Ghani M, Cersosimo E. Novel Agents for the Treatment of Type 2 Diabetes. Diabetes Spectr 2014; 27:100-12. [PMID: 26246766 PMCID: PMC4522879 DOI: 10.2337/diaspect.27.2.100] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In Brief Impaired insulin secretion, increased hepatic glucose production, and decreased peripheral glucose utilization are the core defects responsible for the development and progression of type 2 diabetes. However, the pathophysiology of this disease also includes adipocyte insulin resistance (increased lipolysis), reduced incretin secretion/sensitivity, increased glucagon secretion, enhanced renal glucose reabsorption, and brain insulin resistance/neurotransmitter dysfunction. Although current diabetes management focuses on lowering blood glucose, the goal of therapy should be to delay disease progression and eventual treatment failure. Recent innovative treatment approaches target the multiple pathophysiological defects present in type 2 diabetes. Optimal management should include early initiation of combination therapy using multiple drugs with different mechanisms of action. This review examines novel therapeutic options that hold particular promise.
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Laura de la Garza A, Etxeberria U, Palacios-Ortega S, Haslberger AG, Aumueller E, Milagro FI, Martínez JA. Modulation of hyperglycemia and TNFα-mediated inflammation by helichrysum and grapefruit extracts in diabetic db/db mice. Food Funct 2014; 5:2120-8. [DOI: 10.1039/c4fo00154k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Type-2 diabetes is associated with a chronic low-grade systemic inflammation accompanied by an increased production of adipokines/cytokines in the obese adipose tissue, which may be overcome by flavonoid-rich extracts.
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Affiliation(s)
- Ana Laura de la Garza
- Department of Nutrition
- Food Science and Physiology
- University of Navarra
- 31008 Pamplona, Spain
| | - Usune Etxeberria
- Department of Nutrition
- Food Science and Physiology
- University of Navarra
- 31008 Pamplona, Spain
| | | | | | - Eva Aumueller
- Department of Nutritional Sciences
- University of Vienna
- Vienna, Austria
| | - Fermín I. Milagro
- Department of Nutrition
- Food Science and Physiology
- University of Navarra
- 31008 Pamplona, Spain
- Physiopathology of Obesity and Nutrition
| | - J. Alfredo Martínez
- Department of Nutrition
- Food Science and Physiology
- University of Navarra
- 31008 Pamplona, Spain
- Physiopathology of Obesity and Nutrition
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Myers SA, Nield A, Chew GS, Myers MA. The zinc transporter, Slc39a7 (Zip7) is implicated in glycaemic control in skeletal muscle cells. PLoS One 2013; 8:e79316. [PMID: 24265765 PMCID: PMC3827150 DOI: 10.1371/journal.pone.0079316] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 09/22/2013] [Indexed: 12/12/2022] Open
Abstract
Dysfunctional zinc signaling is implicated in disease processes including cardiovascular disease, Alzheimer's disease and diabetes. Of the twenty-four mammalian zinc transporters, ZIP7 has been identified as an important mediator of the ‘zinc wave’ and in cellular signaling. Utilizing siRNA targeting Zip7 mRNA we have identified that Zip7 regulates glucose metabolism in skeletal muscle cells. An siRNA targeting Zip7 mRNA down regulated Zip7 mRNA 4.6-fold (p = 0.0006) when compared to a scramble control. This was concomitant with a reduction in the expression of genes involved in glucose metabolism including Agl, Dlst, Galm, Gbe1, Idh3g, Pck2, Pgam2, Pgm2, Phkb, Pygm, Tpi1, Gusb and Glut4. Glut4 protein expression was also reduced and insulin-stimulated glycogen synthesis was decreased. This was associated with a reduction in the mRNA expression of Insr, Irs1 and Irs2, and the phosphorylation of Akt. These studies provide a novel role for Zip7 in glucose metabolism in skeletal muscle and highlight the importance of this transporter in contributing to glycaemic control in this tissue.
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Affiliation(s)
- Stephen A. Myers
- Collaborative Research Network and the School of Health Sciences, University of Ballarat, Mount Helen Campus, Victoria, Australia
- * E-mail:
| | - Alex Nield
- Collaborative Research Network and the School of Health Sciences, University of Ballarat, Mount Helen Campus, Victoria, Australia
| | - Guat-Siew Chew
- School of Health Sciences, University of Ballarat, Mount Helen Campus, Victoria, Australia
| | - Mark A. Myers
- Collaborative Research Network and the School of Health Sciences, University of Ballarat, Mount Helen Campus, Victoria, Australia
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Workeneh B, Bajaj M. The regulation of muscle protein turnover in diabetes. Int J Biochem Cell Biol 2013; 45:2239-44. [DOI: 10.1016/j.biocel.2013.06.028] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Revised: 06/28/2013] [Accepted: 06/29/2013] [Indexed: 12/25/2022]
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DeFronzo RA, Eldor R, Abdul-Ghani M. Pathophysiologic approach to therapy in patients with newly diagnosed type 2 diabetes. Diabetes Care 2013; 36 Suppl 2:S127-38. [PMID: 23882037 PMCID: PMC3920797 DOI: 10.2337/dcs13-2011] [Citation(s) in RCA: 188] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Ralph A DeFronzo
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas, USA.
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Eldor R, DeFronzo RA, Abdul-Ghani M. In vivo actions of peroxisome proliferator-activated receptors: glycemic control, insulin sensitivity, and insulin secretion. Diabetes Care 2013; 36 Suppl 2:S162-74. [PMID: 23882042 PMCID: PMC3920780 DOI: 10.2337/dcs13-2003] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Roy Eldor
- Diabetes Division, Department of Medicine, University of Texas Health Science Center, San Antonio, Texas, USA
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Defronzo RA, Mehta RJ, Schnure JJ. Pleiotropic effects of thiazolidinediones: implications for the treatment of patients with type 2 diabetes mellitus. Hosp Pract (1995) 2013; 41:132-147. [PMID: 23680744 DOI: 10.3810/hp.2013.04.1062] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Thiazolidinediones (TZDs) are insulin-sensitizing antidiabetes agents that act through the peroxisome proliferator-activated receptor-γ to cause a durable improvement in glycemic control in patients with type 2 diabetes mellitus. Although less well recognized, TZDs also exert a protective effect on β-cell function. In addition to their beneficial effects on glucose homeostasis, TZDs-especially pioglitazone-exert a number of other pleiotropic effects that make them ideal agents as monotherapy or in combination with other oral agents, glucagon-like peptide-1 analogs, or insulin. Pioglitazone improves endothelial dysfunction, reduces blood pressure, corrects diabetic dyslipidemia, and reduces circulating levels of inflammatory cytokines and prothrombotic factors. Pioglitazone also redistributes fat and toxic lipid metabolites in muscle, liver, β cells, and arteries, and deposits the fat in subcutaneous adipocytes where it cannot exert its lipotoxic effects. Consistent with these antiatherogenic effects, pioglitazone reduced major adverse cardiac event endpoints (ie, mortality, myocardial infarction, and stroke) in the Prospective Pioglitazone Clinical Trial in Macrovascular Events and in a meta-analysis of all other published pioglitazone trials. Pioglitazone also mobilizes fat out of the liver, improving liver function and histologic abnormalities in patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis. Pioglitazone also reduces proteinuria, all-cause mortality, and cardiovascular events in patients with type 2 diabetes mellitus with a reduced glomerular filtration rate. These benefits must be weighed against the side effects of the drug, including weight gain, fluid retention, atypical fractures, and, possibly, bladder cancer. When low doses of pioglitazone are used (eg, 7.5-30 mg/d) with gradual titration, and physician recognition of the potential side effects are applied, the risk-to-benefit ratio is very favorable. Despite having similar effects on glycemic control, pioglitazone and rosiglitazone appear to have different effects on cardiovascular outcomes. Rosiglitazone has been associated with an increased risk of myocardial infarction, and its use in the United States is restricted because of cardiovascular safety concerns.
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Affiliation(s)
- Ralph A Defronzo
- The University of Texas Health Science Center, San Antonio, TX 78229, USA.
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Anti-diabetic effect of amorphastilbol through PPARα/γ dual activation in db/db mice. Biochem Biophys Res Commun 2013; 432:73-9. [DOI: 10.1016/j.bbrc.2013.01.083] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 01/16/2013] [Indexed: 01/31/2023]
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Pinent M, Cedó L, Montagut G, Blay M, Ardévol A. Procyanidins improve some disrupted glucose homoeostatic situations: an analysis of doses and treatments according to different animal models. Crit Rev Food Sci Nutr 2012; 52:569-84. [PMID: 22530710 DOI: 10.1080/10408398.2010.501533] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review analyses the potential beneficial effects of procyanidins, the main class of flavonoids, in situations in which glucose homeostasis is disrupted. Because the disruption of glucose homeostasis can occur as a result of various causes, we critically review the effects of procyanidins based on the specific origin of each type of disruption. Where little or no insulin is present (Type I diabetic animals), summarized studies of procyanidin treatment suggest that procyanidins have a short-lived insulin-mimetic effect on the internal targets of the organism, an effect not reproduced in normoglycemic, normoinsulinemic healthy animals. Insulin resistance (usually linked to hyperinsulinemia) poses a very different situation. Preventive studies using fructose-fed models indicate that procyanidins may be useful in preventing the induction of damage and thus in limiting hyperglycemia. But the results of other studies using models such as high-fat diet treated rats or genetically obese animals are controversial. Although the effects on glucose parameters are hazy, it is known that procyanidins target key tissues involved in its homeostasis. Interestingly, all available data suggest that procyanidins are more effective when administered in one acute load than when mixed with food.
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Affiliation(s)
- Montserrat Pinent
- Departament de Bioquímica i Biotecnologia, Universitat Rovira i Virgili (URV), Tarragona, Spain
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Abstract
OBJECTIVES To assess the association between pre-diabetes and risk of stroke, and to evaluate whether this relation varies by diagnostic criteria for pre-diabetes. DESIGN Systematic review and meta-analysis of prospective studies. DATA SOURCES A search of Medline, Embase, and the Cochrane Library (1947 to 16 July 2011) was supplemented by manual searches of bibliographies of key retrieved articles and relevant reviews. SELECTION CRITERIA Prospective cohort studies that reported multivariate adjusted relative risks and corresponding 95% confidence intervals for stroke with respect to baseline pre-diabetes were included. DATA EXTRACTION Two independent reviewers extracted data on pre-diabetes status at baseline, risk estimates of stroke, study quality, and methods used to assess pre-diabetes and stroke. Relative risks were pooled using random effects models when appropriate. Associations were tested in subgroups representing different characteristics of participants and studies. Publication bias was evaluated with funnel plots. RESULTS The search yielded 15 prospective cohort studies including 760,925 participants. In 8 studies analysing pre-diabetes defined as fasting glucose 100-125 mg/dL (5.6-6.9 mmol/L), the random effects summary estimate did not show an increased risk of stroke after adjustment for established cardiovascular risk factors (1.08, 95% confidence interval 0.94 to 1.23; P = 0.26). In 5 studies analysing pre-diabetes defined as fasting glucose 110-125 mg/dL (6.1-6.9 mmol/L), the random effects summary estimate showed an increased risk of stroke after adjustment for established cardiovascular risk factors (1.21, 1.02 to 1.44; P = 0.03). In 8 studies with information about impaired glucose tolerance or combined impaired glucose tolerance and impaired fasting glucose, the random effects summary estimate showed an increased risk of stroke after adjustment for established cardiovascular risk factors (1.26, 1.10 to 1.43; P < 0.001). When studies that might have enrolled patients with undiagnosed diabetes were excluded, only impaired glucose tolerance or a combination of impaired fasting glucose and impaired glucose tolerance independently raised the future risk of stroke (1.20, 1.07 to 1.35; P = 0.002). CONCLUSION Pre-diabetes, defined as impaired glucose tolerance or a combination of impaired fasting glucose and impaired glucose tolerance, may be associated with a higher future risk of stroke, but the relative risks are modest and may reflect underlying confounding.
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Affiliation(s)
- Meng Lee
- Chang Gung University College of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
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Sgarra L, Addabbo F, Potenza MA, Montagnani M. Determinants of evolving metabolic and cardiovascular benefit/risk profiles of rosiglitazone therapy during the natural history of diabetes: molecular mechanisms in the context of integrated pathophysiology. Am J Physiol Endocrinol Metab 2012; 302:E1171-82. [PMID: 22374753 DOI: 10.1152/ajpendo.00038.2012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Rosiglitazone is a thiazolidinedione, a synthetic PPARγ receptor agonist with insulin-sensitizing properties that is used as an antidiabetic drug. In addition to improving glycemic control through actions in metabolic target tissues, rosiglitazone has numerous biological actions that impact on cardiovascular homeostasis. Some of these actions are helpful (e.g., improving endothelial function), whereas others are potentially harmful (e.g., promoting fluid retention). Since cardiovascular morbidity and mortality are major endpoints for diabetes, it is essential to understand how the natural history of diabetes alters the net benefits and risks of rosiglitazone therapy. This complex issue is an important determinant of optimal use of rosiglitazone and is critical for understanding cardiovascular safety issues. We give special attention to the effects of rosiglitazone in diabetic patients with stable coronary artery disease and the impact of rosiglitazone actions on atherosclerosis and plaque instability. This provides a rational conceptual framework for predicting evolving benefit/risk profiles that inform optimal use of rosiglitazone in the clinical setting and help explain the results of recent large clinical intervention trials where rosiglitazone had disappointing cardiovascular outcomes. Thus, in this perspective, we describe what is known about the molecular mechanisms of action of rosiglitazone on cardiovascular targets in the context of the evolving pathophysiology of diabetes over its natural history.
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Affiliation(s)
- Luca Sgarra
- Department of Biomedical Sciences and Human Oncology, Medical School, University of Bari, Bari, Italy
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Doiron B, Hu W, Norton L, DeFronzo RA. Lentivirus shRNA Grb10 targeting the pancreas induces apoptosis and improved glucose tolerance due to decreased plasma glucagon levels. Diabetologia 2012; 55:719-28. [PMID: 22222503 DOI: 10.1007/s00125-011-2414-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 11/24/2011] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS The physiological significance of growth factor receptor-bound protein-10 (GRB10) in the pancreas is unclear. We hypothesised that GRB10 is involved in pancreatic apoptosis, as GRB10 binds with a family of cell-survival-related proteins implicated in apoptosis. METHODS Lentiviral vector small hairpin RNA (shRNA) targeting Grb10 was injected in vivo via an intraductal pancreatic route to target pancreatic tissues in adult mice, which were studied 2 weeks post-injection. RESULTS Using the TUNEL assay, we demonstrated for the first time that in vivo injection of lentivirus shRNA Grb10 directly into the adult mouse pancreas induced apoptosis in both exocrine and endocrine (alpha and beta) cells. This effect was more pronounced in alpha cells. Levels of the pro-apoptotic protein BCL2-interacting mediator of cell death (BIM) in islets was higher in lentivirus shRNA Grb10 than in lentivirus shRNA scramble mice. In the apoptotic pathway, BIM initiates apoptosis signalling, leading to activation of the caspase cascade. We propose that, when complexed with GRB10, BIM is inactive. On activation by stress signalling or, in the present study, following injection of lentivirus shRNA Grb10 into pancreas, BIM becomes unbound from GRB10 and activates the caspase cascade. Indeed, caspase-3 activity in islets was higher in the experimental than in the control group. Apoptosis induced by shRNA Grb10 resulted in a 34% decrease in fasting plasma glucagon. Mice injected with shRNA Grb10 had improved glucose tolerance despite reduced insulin secretion compared with shRNA scramble control mice. CONCLUSIONS/INTERPRETATION GRB10 is critically involved in alpha cell survival and, as a result, plays an important role in regulating basal glucagon secretion and glucose tolerance in adult mice.
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Affiliation(s)
- B Doiron
- Diabetes Division, University of Texas Health Science Center at San Antonio, Mail Code 7886, 7703 Floyd Curl Drive, San Antonio, TX 78299, USA.
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NF-kB activation as a molecular basis of pathological process by metabolic syndrome. ACTA ACUST UNITED AC 2012. [DOI: 10.15407/fz58.01.093] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Alonso N, Julián MT, Puig-Domingo M, Vives-Pi M. Incretin hormones as immunomodulators of atherosclerosis. Front Endocrinol (Lausanne) 2012; 3:112. [PMID: 22973260 PMCID: PMC3435665 DOI: 10.3389/fendo.2012.00112] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 08/22/2012] [Indexed: 12/25/2022] Open
Abstract
Atherosclerosis results from endothelial cell dysfunction and inflammatory processes affecting both macro- and microvasculature which are involved in vascular diabetic complications. Glucagon-like peptide-1 (GLP-1) is an incretin hormone responsible for amplification of insulin secretion when nutrients are given orally as opposed to intravenously and it retains its insulinotropic activity in patients with type 2 diabetes mellitus (T2D). GLP-1 based therapies, such as GLP-1 receptor (GLP-1R) agonists and inhibitors of dipeptidyl peptidase-4, an enzyme that degrades endogenous GLP-1 are routinely used to treat patients with T2D. Recent experimental model studies have established that GLP-1R mRNA is widely expressed in several immune cells. Moreover, its activation contributes to the regulation of both thymocyte and peripheral T cells proliferation and is involved in the maintenance of peripheral regulatory T cells. GLP-1R is also expressed in endothelial and smooth muscle cells. The effect of incretin hormones on atherosclerogenesis have recently been studied in animal models of apolipoprotein E-deficient mice (apoE(-/-)). These studies have demonstrated that treatment with incretin hormones or related compounds suppresses the progression of atherosclerosis and macrophage infiltration in the arterial wall as well as a marked anti-oxidative and anti-inflammatory effect on endothelial cells. This effect may have a major impact on the attenuation of atherosclerosis and may help in the design of new therapies for cardiovascular disease in patients with type 2 diabetes.
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Affiliation(s)
- Nuria Alonso
- Endocrinology and Nutrition Department, Hospital Universitari Germans Trias i PujolBadalona, Spain
- *Correspondence: Nuria Alonso, Endocrinology and Nutrition Department, Hospital Universitari Germans Trias i Pujol, Carretera Canyet s/n, 08916 Badalona, Spain. e-mail:
| | - M. Teresa Julián
- Endocrinology and Nutrition Department, Hospital Universitari Germans Trias i PujolBadalona, Spain
| | - Manuel Puig-Domingo
- Endocrinology and Nutrition Department, Hospital Universitari Germans Trias i PujolBadalona, Spain
| | - Marta Vives-Pi
- Laboratory of Immunobiology for Research and Application to Diagnosis, Blood and Tissue Bank, Institute Germans Trias i PujolBadalona, Spain
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Fernandez M, Gastaldelli A, Triplitt C, Hardies J, Casolaro A, Petz R, Tantiwong P, Musi N, Cersosimo E, Ferrannini E, DeFronzo RA. Metabolic effects of muraglitazar in type 2 diabetic subjects. Diabetes Obes Metab 2011; 13:893-902. [PMID: 21615671 DOI: 10.1111/j.1463-1326.2011.01429.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To assess the effect of muraglitazar, a dual peroxisome proliferator-activated receptor (PPAR)γ-α agonist, versus placebo on metabolic parameters and body composition in subjects with type 2 diabetes mellitus (T2DM). METHODS Twenty-seven T2DM subjects received oral glucose tolerance test (OGTT), euglycaemic insulin clamp with deuterated glucose, measurement of total body fat (DEXA), quantitation of muscle/liver (MRS) and abdominal subcutaneous and visceral (MRI) fat, and then were randomized to receive, in addition to diet, muraglitazar (MURA), 5 mg/day, or placebo (PLAC) for 4 months. RESULTS HbA1c(c) decreased similarly (2.1%) during both MURA and PLAC treatments despite significant weight gain with MURA (+2.5 kg) and weight loss with PLAC (-0.7 kg). Plasma triglyceride, LDL cholesterol, free fatty acid (FFA), hsCRP levels all decreased with MURA while plasma adiponectin and HDL cholesterol increased (p < 0.05-0.001). Total body (muscle), hepatic and adipose tissue sensitivity to insulin and β cell function all improved with MURA (p < 0.05-0.01). Intramyocellular, hepatic and abdominal visceral fat content decreased, while total body and subcutaneous abdominal fat increased with MURA (p < 0.05-0.01). CONCLUSIONS Muraglitazar (i) improves glycaemic control by enhancing insulin sensitivity and β cell function in T2DM subjects, (ii) improves multiple cardiovascular risk factors, (iii) reduces muscle, visceral and hepatic fat content in T2DM subjects. Despite similar reduction in A1c with PLAC/diet, insulin sensitivity and β cell function did not improve significantly.
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Affiliation(s)
- M Fernandez
- University of Texas Health Science Center and Texas Diabetes Institute, San Antonio, TX 78229-3900, USA
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DeFronzo RA, Abdul-Ghani M. Assessment and treatment of cardiovascular risk in prediabetes: impaired glucose tolerance and impaired fasting glucose. Am J Cardiol 2011; 108:3B-24B. [PMID: 21802577 DOI: 10.1016/j.amjcard.2011.03.013] [Citation(s) in RCA: 224] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Individuals with impaired glucose tolerance (IGT) and/or impaired fasting glucose (IFG) are at high risk, not only to develop diabetes mellitus, but also to experience an adverse cardiovascular (CV) event (myocardial infarction, stroke, CV death) later in life. The underlying pathophysiologic disturbances (insulin resistance and impaired β-cell function) responsible for the development of type 2 diabetes are maximally/near maximally expressed in subjects with IGT/IFG. These individuals with so-called prediabetes manifest all of the same CV risk factors (dysglycemia, dyslipidemia, hypertension, obesity, physical inactivity, insulin resistance, procoagulant state, endothelial dysfunction, inflammation) that place patients with type 2 diabetes at high risk for macrovascular complications. The treatment of these CV risk factors should follow the same guidelines established for patients with type 2 diabetes, and should be aggressively followed to reduce future CV events.
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Affiliation(s)
- Ralph A DeFronzo
- Diabetes Division, University of Texas Health Science Center, San Antonio, Texas 78229, USA.
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Yeste D, Carrascosa A. [Obesity-related metabolic disorders in childhood and adolescence]. An Pediatr (Barc) 2011; 75:135.e1-9. [PMID: 21571600 DOI: 10.1016/j.anpedi.2011.03.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2011] [Revised: 03/22/2011] [Accepted: 03/30/2011] [Indexed: 11/29/2022] Open
Abstract
Obesity is the most frequent nutritional disorder in childhood and adolescence. The rise in its prevalence and severity has underlined the numerous and significant obesity-related metabolic disorders. Altered glucose metabolism, manifested as impaired glucose tolerance, appears early in severely obese children and adolescents. Obese young people with glucose intolerance are characterized by marked peripheral insulin resistance and relative beta-cell failure. Lipid deposition in muscle and the visceral compartment, and not only obesity per se, is related to increased peripheral insulin resistance, the triggering factor of the metabolic syndrome. Other elements of the metabolic syndrome, such as dyslipidaemia, and hypertension, are already present in obese youngsters and worsen with the degree of obesity. The long-term impact of obesity-related insulin resistance on cardiovascular morbidity in these patients is expected to emerge as these youngsters become young adults.
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Affiliation(s)
- D Yeste
- Servicio de Pediatría, Unidades de Endocrinología y Obesidad Pediátrica, Hospital Universitario Vall d' Hebron, Barcelona, Universidad Autónoma de Barcelona, España.
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Zhang X, Wang Z, Huang Y, Wang J. Effects of chronic administration of alogliptin on the development of diabetes and β-cell function in high fat diet/streptozotocin diabetic mice. Diabetes Obes Metab 2011; 13:337-47. [PMID: 21205126 DOI: 10.1111/j.1463-1326.2010.01354.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
AIM Alogliptin is a potent and highly selective dipeptidyl peptidase-4 (DPP-4) inhibitor. The aim of this study was to determine its effects on glucose control and pancreas islet function and to identify the underlying molecular mechanisms after chronic administration, in a non-genetic mouse model of type 2 diabetes. METHODS Alogliptin (5, 15 and 45 mg/kg) was orally administered to high fat diet/streptozotocin (HFD/STZ) diabetic mice daily for 10 weeks. Postprandial and 6-h fasting blood glucose levels, blood A1C level, oral glucose tolerance and pancreas insulin content were measured during or after the treatment period. Alogliptin plasma concentration was determined by an LC/MS/MS method. Islet morphology and architectural changes were evaluated with immunohistochemical analysis. Islet endocrine secretion ability was assessed by measuring insulin release from isolated islets which were challenged with 16 mM glucose and 30 mM potassium chloride, respectively. Gene expression profiles of the pancreas were analysed using the mouse diabetes RT(2) Profiler PCR array which contains 84 genes related to the onset, development and progression of diabetes. RESULTS Alogliptin showed dose-dependent reduction of postprandial and fasting blood glucose levels and blood A1C levels. Glucose clearance ability and pancreas insulin content were both increased. Alogliptin significantly restored the β-cell mass and islet morphology, thus preserving islet function of insulin secretion. Expression of 10 genes including Ins1 was significantly changed in the pancreas of diabetic mice. Chronic alogliptin treatment completely or partially reversed the abnormalities in gene expression. CONCLUSIONS Chronic treatment of alogliptin improved glucose control and facilitated restoration of islet architecture and function in HFD/STZ diabetic mice. The gene expression profiles suggest that the underlying molecular mechanisms of β-cell protection by alogliptin may involve alleviating endoplasmic reticulum burden and mitochondria oxidative stress, increasing β-cell differentiation and proliferation, enhancing islet architecture remodelling and preserving islet function.
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Affiliation(s)
- X Zhang
- Department of Pharmaceutical Sciences, College of Pharmacy, Western University of Health Sciences, 309 E. Second Street, Pomona, CA 91766, USA
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DeFronzo RA. Insulin resistance, lipotoxicity, type 2 diabetes and atherosclerosis: the missing links. The Claude Bernard Lecture 2009. Diabetologia 2010; 53:1270-87. [PMID: 20361178 PMCID: PMC2877338 DOI: 10.1007/s00125-010-1684-1] [Citation(s) in RCA: 563] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 12/22/2009] [Indexed: 12/15/2022]
Abstract
Insulin resistance is a hallmark of type 2 diabetes mellitus and is associated with a metabolic and cardiovascular cluster of disorders (dyslipidaemia, hypertension, obesity [especially visceral], glucose intolerance, endothelial dysfunction), each of which is an independent risk factor for cardiovascular disease (CVD). Multiple prospective studies have documented an association between insulin resistance and accelerated CVD in patients with type 2 diabetes, as well as in non-diabetic individuals. The molecular causes of insulin resistance, i.e. impaired insulin signalling through the phosphoinositol-3 kinase pathway with intact signalling through the mitogen-activated protein kinase pathway, are responsible for the impairment in insulin-stimulated glucose metabolism and contribute to the accelerated rate of CVD in type 2 diabetes patients. The current epidemic of diabetes is being driven by the obesity epidemic, which represents a state of tissue fat overload. Accumulation of toxic lipid metabolites (fatty acyl CoA, diacylglycerol, ceramide) in muscle, liver, adipocytes, beta cells and arterial tissues contributes to insulin resistance, beta cell dysfunction and accelerated atherosclerosis, respectively, in type 2 diabetes. Treatment with thiazolidinediones mobilises fat out of tissues, leading to enhanced insulin sensitivity, improved beta cell function and decreased atherogenesis. Insulin resistance and lipotoxicity represent the missing links (beyond the classical cardiovascular risk factors) that help explain the accelerated rate of CVD in type 2 diabetic patients.
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Affiliation(s)
- R A DeFronzo
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive-MSC 7886, San Antonio, TX, 78229, USA.
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Nelson RA, Bremer AA. Insulin resistance and metabolic syndrome in the pediatric population. Metab Syndr Relat Disord 2010; 8:1-14. [PMID: 19943799 DOI: 10.1089/met.2009.0068] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The metabolic syndrome is a constellation of specific anthropometric, physiological, and biochemical abnormalities predisposing affected individuals to the development of diabetes and cardiovascular disease. The syndrome is well described in the adult literature. However, its description in the pediatric literature is more limited. Due in large part to the normal physiological changes that occur in children and adolescents with respect to growth and puberty, investigators have also struggled to establish a standard definition of the syndrome in the pediatric age group, hindering coordinated research efforts. However, whatever definition of the syndrome is used, the prevalence of the metabolic syndrome in the pediatric age group has increased worldwide. Insulin resistance is the principal metabolic abnormality that is common to the development of the metabolic syndrome in both children and adults. This review summarizes current research regarding the pathophysiology of insulin resistance and how this may contribute to specific abnormalities seen in children and adolescents with the metabolic syndrome. Specifically, insulin resistance in pediatric patients is correlated with cardiovascular risk factors such as elevated blood pressure, dyslipidemia, and type 2 diabetes mellitus, all of which are significant risk factors for adult disease. In addition, current treatment and prevention strategies, including lifestyle modifications, pharmacologic agents, and certain surgical therapies, are highlighted. The need for collaborative changes at the family, school, city, state, and national levels to address the growing prevalence of the metabolic syndrome in the pediatric age group is also reviewed.
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Affiliation(s)
- Rachel A Nelson
- Department of Pediatrics, University of California Davis Medical Center, Sacramento, California 95817-2208, USA
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Pathogenesis of insulin resistance in skeletal muscle. J Biomed Biotechnol 2010; 2010:476279. [PMID: 20445742 PMCID: PMC2860140 DOI: 10.1155/2010/476279] [Citation(s) in RCA: 377] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2009] [Accepted: 01/20/2010] [Indexed: 12/16/2022] Open
Abstract
Insulin resistance in skeletal muscle is manifested by decreased insulin-stimulated glucose uptake and results from impaired insulin signaling and multiple post-receptor intracellular defects including impaired glucose transport, glucose phosphorylation, and reduced glucose oxidation and glycogen synthesis. Insulin resistance is a core defect in type 2 diabetes, it is also associated with obesity and the metabolic syndrome. Dysregulation of fatty acid metabolism plays a pivotal role in the pathogenesis of insulin resistance in skeletal muscle. Recent studies have reported a mitochondrial defect in oxidative phosphorylation in skeletal muscle in variety of insulin resistant states. In this review, we summarize the cellular and molecular defects that contribute to the development of insulin resistance in skeletal muscle.
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