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Prado CM, Batsis JA, Donini LM, Gonzalez MC, Siervo M. Sarcopenic obesity in older adults: a clinical overview. Nat Rev Endocrinol 2024; 20:261-277. [PMID: 38321142 DOI: 10.1038/s41574-023-00943-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/15/2023] [Indexed: 02/08/2024]
Abstract
Sarcopenic obesity is characterized by a concurrent decline in muscle mass and function, along with increased adipose tissue. Sarcopenic obesity is a growing concern in older adults owing to significant health consequences, including implications for mortality, comorbidities and risk of developing geriatric syndromes. A 2022 consensus statement established a new definition and diagnostic criteria for sarcopenic obesity. The pathophysiology of this condition involves a complex interplay between muscle, adipose tissue, hormonal changes, inflammation, oxidative stress and lifestyle factors, among others. Sarcopenic obesity is treated with a range of management approaches, such as lifestyle interventions, exercise, nutrition and medical therapies. Emerging therapies that were developed for treating other conditions may be relevant to sarcopenic obesity, including novel pharmacological agents and personalized approaches such as precision medicine. In this Review, we synthesize the current knowledge of the clinical importance of sarcopenic obesity, its assessment and diagnosis, along with current and emerging management strategies.
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Affiliation(s)
- Carla M Prado
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada.
| | - John A Batsis
- Division of Geriatric Medicine, School of Medicine, and Department of Nutrition, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lorenzo M Donini
- Department of Experimental Medicine, Sapienza University, Rome, Italy
| | - M Cristina Gonzalez
- Postgraduate Program in Nutrition and Food, Pelotas, Federal University of Pelotas, Pelotas, Rio Grande do Sul, Brazil
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Mario Siervo
- School of Population Health, Curtin University, Perth, Western Australia, Australia
- Curtin Dementia Centre of Excellence, enAble Institute, Curtin University, Perth, Western Australia, Australia
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Yalaz C, Bridges E, Alham NK, Zois CE, Chen J, Bensaad K, Miar A, Pires E, Muschel RJ, McCullagh JSO, Harris AL. Cone photoreceptor phosphodiesterase PDE6H inhibition regulates cancer cell growth and metabolism, replicating the dark retina response. Cancer Metab 2024; 12:5. [PMID: 38350962 PMCID: PMC10863171 DOI: 10.1186/s40170-023-00326-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 11/24/2023] [Indexed: 02/15/2024] Open
Abstract
BACKGROUND PDE6H encodes PDE6γ', the inhibitory subunit of the cGMP-specific phosphodiesterase 6 in cone photoreceptors. Inhibition of PDE6, which has been widely studied for its role in light transduction, increases cGMP levels. The purpose of this study is to characterise the role of PDE6H in cancer cell growth. METHODS From an siRNA screen for 487 genes involved in metabolism, PDE6H was identified as a controller of cell cycle progression in HCT116 cells. Role of PDE6H in cancer cell growth and metabolism was studied through the effects of its depletion on levels of cell cycle controllers, mTOR effectors, metabolite levels, and metabolic energy assays. Effect of PDE6H deletion on tumour growth was also studied in a xenograft model. RESULTS PDE6H knockout resulted in an increase of intracellular cGMP levels, as well as changes to the levels of nucleotides and key energy metabolism intermediates. PDE6H knockdown induced G1 cell cycle arrest and cell death and reduced mTORC1 signalling in cancer cell lines. Both knockdown and knockout of PDE6H resulted in the suppression of mitochondrial function. HCT116 xenografts revealed that PDE6H deletion, as well as treatment with the PDE5/6 inhibitor sildenafil, slowed down tumour growth and improved survival, while sildenafil treatment did not have an additive effect on slowing the growth of PDE6γ'-deficient tumours. CONCLUSIONS Our results indicate that the changes in cGMP and purine pools, as well as mitochondrial function which is observed upon PDE6γ' depletion, are independent of the PKG pathway. We show that in HCT116, PDE6H deletion replicates many effects of the dark retina response and identify PDE6H as a new target in preventing cancer cell proliferation and tumour growth.
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Affiliation(s)
- Ceren Yalaz
- Molecular Oncology Laboratories, Department of Medical Oncology, John Radcliffe Hospital, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK.
| | - Esther Bridges
- Molecular Oncology Laboratories, Department of Medical Oncology, John Radcliffe Hospital, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Nasullah K Alham
- Department of Engineering Science, Institute of Biomedical Engineering (IBME), University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Christos E Zois
- Molecular Oncology Laboratories, Department of Medical Oncology, John Radcliffe Hospital, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Jianzhou Chen
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Karim Bensaad
- Molecular Oncology Laboratories, Department of Medical Oncology, John Radcliffe Hospital, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Ana Miar
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Elisabete Pires
- Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK
| | - Ruth J Muschel
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - James S O McCullagh
- Department of Chemistry, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK
| | - Adrian L Harris
- Molecular Oncology Laboratories, Department of Medical Oncology, John Radcliffe Hospital, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
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Ouassou H, Elhouda Daoudi N, Bouknana S, Abdnim R, Bnouham M. A Review of Antidiabetic Medicinal Plants as a Novel Source of Phosphodiesterase Inhibitors: Future Perspective of New Challenges Against Diabetes Mellitus. Med Chem 2024; 20:467-486. [PMID: 38265379 DOI: 10.2174/0115734064255060231116192839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/31/2023] [Accepted: 09/25/2023] [Indexed: 01/25/2024]
Abstract
Intracellular glucose concentration plays a crucial role in initiating the molecular secretory process of pancreatic β-cells through multiple messengers and signaling pathways. Cyclic nucleotides are key physiological regulators that modulate pathway interactions in β -cells. An increase of cyclic nucleotides is controled by hydrolysed phosphodiesterases (PDEs), which degrades cyclic nucleotides into inactive metabolites. Despite the undeniable therapeutic potential of PDE inhibitors, they are associated with several side effects. The treatment strategy for diabetes based on PDE inhibitors has been proposed for a long time. Hence, the world of natural antidiabetic medicinal plants represents an ideal source of phosphodiesterase inhibitors as a new strategy for developing novel agents to treat diabetes mellitus. This review highlights medicinal plants traditionally used in the treatment of diabetes mellitus that have been proven to have inhibitory effects on PDE activity. The contents of this review were sourced from electronic databases, including Science Direct, PubMed, Springer Link, Web of Science, Scopus, Wiley Online, Scifinder and Google Scholar. These databases were consulted to collect information without any limitation date. After comprehensive literature screening, this paper identified 27 medicinal plants that have been reported to exhibit anti-phosphodiesterase activities. The selection of these plants was based on their traditional uses in the treatment of diabetes mellitus. The review emphasizes the antiphosphodiesterase properties of 31 bioactive components derived from these plant extracts. Many phenolic compounds have been identified as PDE inhibitors: Brazilin, mesozygin, artonin I, chalcomaracin, norartocarpetin, moracin L, moracin M, moracin C, curcumin, gallic acid, caffeic acid, rutin, quercitrin, quercetin, catechin, kaempferol, chlorogenic acid, and ellagic acid. Moreover, smome lignans have reported as PDE inhibitors: (+)-Medioresinol di-O-β-d-glucopyranoside, (+)- Pinoresinol di-O-β-d-glucopyranoside, (+)-Pinoresinol-4-O-β-d-glucopyranosyl (1→6)-β-dglucopyranoside, Liriodendrin, (+)-Pinoresinol 4'-O-β-d-glucopyranoside, and forsythin. This review provides a promising starting point of medicinal plants, which could be further studied for the development of natural phosphodiesterase inhibitors to treat diabetes mellitus. Therefore, it is important to consider clinical studies for the identification of new targets for the treatment of diabetes.
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Affiliation(s)
- Hayat Ouassou
- Higher Institute of Nurses Professions and Health Techniques, Oujda 60000, Morocco
- Laboratory of Bioresources, Biotechnology, Ethnopharmacology and Health, Department of Biology, Faculty of Sciences, Mohammed First University, BP. 717, Oujda 60040, Morocco
| | - Nour Elhouda Daoudi
- Laboratory of Bioresources, Biotechnology, Ethnopharmacology and Health, Department of Biology, Faculty of Sciences, Mohammed First University, BP. 717, Oujda 60040, Morocco
| | - Saliha Bouknana
- Department of Biology, Faculty of Sciences, University Mohammed First, Boulevard Mohamed VI BP 717, Oujda 60040, Morocco
| | - Rhizlan Abdnim
- Laboratory of Bioresources, Biotechnology, Ethnopharmacology and Health, Department of Biology, Faculty of Sciences, Mohammed First University, BP. 717, Oujda 60040, Morocco
| | - Mohamed Bnouham
- Laboratory of Bioresources, Biotechnology, Ethnopharmacology and Health, Department of Biology, Faculty of Sciences, Mohammed First University, BP. 717, Oujda 60040, Morocco
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Chang YC, Chan MH, Yang YF, Li CH, Hsiao M. Glucose transporter 4: Insulin response mastermind, glycolysis catalyst and treatment direction for cancer progression. Cancer Lett 2023; 563:216179. [PMID: 37061122 DOI: 10.1016/j.canlet.2023.216179] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/27/2023] [Accepted: 04/07/2023] [Indexed: 04/17/2023]
Abstract
The glucose transporter family (GLUT) consists of fourteen members. It is responsible for glucose homeostasis and glucose transport from the extracellular space to the cell cytoplasm to further cascade catalysis. GLUT proteins are encoded by the solute carrier family 2 (SLC2) genes and are members of the major facilitator superfamily of membrane transporters. Moreover, different GLUTs also have their transporter kinetics and distribution, so each GLUT member has its uniqueness and importance to play essential roles in human physiology. Evidence from many studies in the field of diabetes showed that GLUT4 travels between the plasma membrane and intracellular vesicles (GLUT4-storage vesicles, GSVs) and that the PI3K/Akt pathway regulates this activity in an insulin-dependent manner or by the AMPK pathway in response to muscle contraction. Moreover, some published results also pointed out that GLUT4 mediates insulin-dependent glucose uptake. Thus, dysfunction of GLUT4 can induce insulin resistance, metabolic reprogramming in diverse chronic diseases, inflammation, and cancer. In addition to the relationship between GLUT4 and insulin response, recent studies also referred to the potential upstream transcription factors that can bind to the promoter region of GLUT4 to regulating downstream signals. Combined all of the evidence, we conclude that GLUT4 has shown valuable unknown functions and is of clinical significance in cancers, which deserves our in-depth discussion and design compounds by structure basis to achieve therapeutic effects. Thus, we intend to write up a most updated review manuscript to include the most recent and critical research findings elucidating how and why GLUT4 plays an essential role in carcinogenesis, which may have broad interests and impacts on this field.
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Affiliation(s)
- Yu-Chan Chang
- Department of Biomedical Imaging and Radiological Science, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ming-Hsien Chan
- Department of Biomedical Imaging and Radiological Science, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-Fang Yang
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Chien-Hsiu Li
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | - Michael Hsiao
- Genomics Research Center, Academia Sinica, Taipei, Taiwan; Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Transcriptome-Wide Study Revealed That N6-Methyladenosine Participates in Regulation Meat Production in Goats. Foods 2023; 12:foods12061159. [PMID: 36981086 PMCID: PMC10048064 DOI: 10.3390/foods12061159] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 02/28/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
In mammals, skeletal muscle development is a complex biological process regulated by many factors. N6-methyladenosine (m6A) RNA modification plays an important role in many biological processes. However, the regulation of m6A on skeletal muscle growth and development in adult goats remains unclear. In this study, Duan goats (DA) and Nubia goats (NBY), both female and 12 months old, were selected as the research objects, and m6A-Seq and RNA-Seq were mainly used to detect the difference of m6A modification and gene expression during the development of the longissimus dorsi (LD) muscle in the two breeds. The results showed that compared with DA, the meat production performance of NBY was better than that of DA, and the modification level of m6A was higher than that of DA in LD. The m6A-Seq of LD indicated m6A peaks were mainly enriched in the coding sequence (CDS) and stop codon. A total of 161 differentially methylated genes (DMGs) and 1294 differentially expressed genes (DEGs) were identified in two breeds. GO and KEGG analysis showed that DMGs were closely related to cellular metabolism, and most of DMGs were enriched in pathways related to energy metabolism, muscle growth and development, mainly MAPK signaling pathway, Wnt signaling pathway and CGMP-PKG signaling pathway. The DEGs were significantly enriched in actin binding, calcium ion binding, angiogenesis, and other biological processes, and most of them were enriched in PI3K-Akt and CGMP-PKG signaling pathways. Combined analysis of m6A-Seq and RNA-Seq data revealed a negative correlation between differentially methylated m6A levels and mRNA abundance, and mRNA expression of the gene with m6A peak near 3′UTR will decrease. In addition, 11 DMGs regulating cell differentiation, muscle growth and development were identified. This study displayed the m6A profiles and distribution patterns in the goat transcriptome, determined the potential role of m6A modification in muscle growth and provided a new reference for the further study of goat skeletal muscle development.
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Pappas G, Wilkinson ML, Gow AJ. Nitric oxide regulation of cellular metabolism: Adaptive tuning of cellular energy. Nitric Oxide 2023; 131:8-17. [PMID: 36470373 PMCID: PMC9839556 DOI: 10.1016/j.niox.2022.11.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 10/24/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022]
Abstract
Nitric oxide can interact with a wide range of proteins including many that are involved in metabolism. In this review we have summarized the effects of NO on glycolysis, fatty acid metabolism, the TCA cycle, and oxidative phosphorylation with reference to skeletal muscle. Low to moderate NO concentrations upregulate glucose and fatty acid oxidation, while higher NO concentrations shift cellular reliance toward a fully glycolytic phenotype. Moderate NO production directly inhibits pyruvate dehydrogenase activity, reducing glucose-derived carbon entry into the TCA cycle and subsequently increasing anaploretic reactions. NO directly inhibits aconitase activity, increasing reliance on glutamine for continued energy production. At higher or prolonged NO exposure, citrate accumulation can inhibit multiple ATP-producing pathways. Reduced TCA flux slows NADH/FADH entry into the ETC. NO can also inhibit the ETC directly, further limiting oxidative phosphorylation. Moderate NO production improves mitochondrial efficiency while improving O2 utilization increasing whole-body energy production. Long-term bioenergetic capacity may be increased because of NO-derived ROS, which participate in adaptive cellular redox signaling through AMPK, PCG1-α, HIF-1, and NF-κB. However, prolonged exposure or high concentrations of NO can result in membrane depolarization and opening of the MPT. In this way NO may serve as a biochemical rheostat matching energy supply with demand for optimal respiratory function.
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Affiliation(s)
- Gregory Pappas
- Department of Kinesiology & Applied Physiology, Rutgers the State University of New Jersey, NJ, 08854, USA.
| | - Melissa L Wilkinson
- Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers the State University of New Jersey, NJ, 08854, USA.
| | - Andrew J Gow
- Department of Kinesiology & Applied Physiology, Rutgers the State University of New Jersey, NJ, 08854, USA; Department of Pharmacology and Toxicology, Ernest Mario School of Pharmacy, Rutgers the State University of New Jersey, NJ, 08854, USA.
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Rogacka D, Rachubik P, Audzeyenka I, Szrejder M, Kulesza T, Myślińska D, Angielski S, Piwkowska A. Enhancement of cGMP-dependent pathway activity ameliorates hyperglycemia-induced decrease in SIRT1-AMPK activity in podocytes: Impact on glucose uptake and podocyte function. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119362. [PMID: 36152759 DOI: 10.1016/j.bbamcr.2022.119362] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 09/01/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
Hyperglycemia significantly decreases 3',5'-cyclic guanosine monophosphate (cGMP)-dependent pathway activity in the kidney. A well-characterized downstream signaling effector of cGMP is cGMP-dependent protein kinase G (PKG), exerting a wide range of downstream effects, including vasodilation and vascular smooth muscle cells relaxation. In podocytes that are exposed to high glucose concentrations, crosstalk between the protein deacetylase sirtuin 1 (SIRT1) and adenosine monophosphate-dependent protein kinase (AMPK) decreased, attenuating insulin responsiveness and impairing podocyte function. The present study examined the effect of enhancing cGMP-dependent pathway activity on SIRT1-AMPK crosstalk in podocytes under hyperglycemic conditions. We found that enhancing cGMP-dependent pathway activity using a cGMP analog was associated with increases in SIRT1 protein levels and activity, with a concomitant increase in the degree of AMPK phosphorylation. The beneficial effects of enhancing cGMP-dependent pathway activity on SIRT1-AMPK crosstalk also included improvements in podocyte function. Based on our findings, we postulate an important role for SIRT1-AMPK crosstalk in the regulation of albumin permeability in hyperglycemia that is strongly associated with activity of the cGMP-dependent pathway.
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Affiliation(s)
- Dorota Rogacka
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland; Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Gdansk, Poland.
| | - Patrycja Rachubik
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland
| | - Irena Audzeyenka
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland; Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Gdansk, Poland
| | - Maria Szrejder
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland
| | - Tomasz Kulesza
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland
| | - Dorota Myślińska
- Department of Animal and Human Physiology, Faculty of Biology, University of Gdansk, Gdansk, Poland
| | - Stefan Angielski
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland
| | - Agnieszka Piwkowska
- Laboratory of Molecular and Cellular Nephrology, Mossakowski Medical Research Institute, Polish Academy of Sciences, Gdansk, Poland; Department of Molecular Biotechnology, Faculty of Chemistry, University of Gdansk, Gdansk, Poland
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Skeletal Muscle CSE Deficiency Leads to Insulin Resistance in Mice. Antioxidants (Basel) 2022; 11:antiox11112216. [PMID: 36358588 PMCID: PMC9687043 DOI: 10.3390/antiox11112216] [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: 09/22/2022] [Revised: 10/28/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
Cystathionine-γ-lyase (CSE) is expressed in various tissues and generates H2S via an alternative desulfuration reaction. We sought to explore the functions of skeletal muscle CSE using skeletal muscle conditional knockout CSE (MCSEKO) mice. It was found that body weight, muscle morphology, and exercise capacity were not altered in MCSEKO mice compared with littermate wild-type mice. RNA-seq-based transcriptome analysis showed that 275 genes were differentially regulated in skeletal muscle and multiple signaling pathways including insulin signaling and mTOR, PI3K-AKT, and cGMP-PKG signaling pathways were enriched in MCSEKO mice. The intraperitoneal glucose tolerance test and insulin tolerance test showed that glucose tolerance and insulin sensitivity were reduced in MCSEKO mice. Glucose transporter 4 (GLU4) and PKG-1 expression levels and insulin receptor substrate-1(IRS1)/PI3K/Akt signaling pathway were downregulated whilst the mTOR/S6K/S6 pathway was enhanced in MCSEKO mice. These effects were reversed by the H2S supplement. Aerobic treadmill training significantly promoted glucose tolerance and insulin sensitivity and improved GLU4 and PKG-1 levels, promoted IRS1/PI3K/Akt signaling and suppressed mTOR/S6K/S6 signaling pathway in MCSEKO mice. Our data suggest that skeletal muscle CSE/H2S signaling is critical for the maintenance of insulin sensitivity, which is associated with maintaining the balance in PKG, PI3K/Akt, and mTOR/S6K/S6 signaling pathways in skeletal muscle.
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Olgar Y, Durak A, Bitirim CV, Tuncay E, Turan B. Insulin acts as an atypical KCNQ1/KCNE1-current activator and reverses long QT in insulin-resistant aged rats by accelerating the ventricular action potential repolarization through affecting the β 3 -adrenergic receptor signaling pathway. J Cell Physiol 2021; 237:1353-1371. [PMID: 34632595 DOI: 10.1002/jcp.30597] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 12/13/2022]
Abstract
Insufficient-heart function is associated with myocardial insulin resistance in the elderly, particularly associated with long-QT, in a dependency on dysfunctional KCNQ1/KCNE1-channels. So, we aimed to examine the contribution of alterations in KCNQ1/KCNE1-current (IKs ) to the aging-related remodeling of the heart as well as the role of insulin treatment on IKs in the aged rats. Prolonged late-phase action potential (AP) repolarization of ventricular cardiomyocytes from insulin-resistant 24-month-old rats was significantly reversed by in vitro treatment of insulin or PKG inhibitor (in vivo, as well) via recovery in depressed IKs . Although the protein level of either KCNQ1 or KCNE1 in cardiomyocytes was not affected with aging, PKG level was significantly increased in those cells. The inhibited IKs in β3 -ARs-stimulated cells could be reversed with a PKG inhibitor, indicating the correlation between PKG-activation and β3 -ARs activation. Furthermore, in vivo treatment of aged rats, characterized by β3 -ARs activation, with either insulin or a PKG inhibitor for 2 weeks provided significant recoveries in IKs , prolonged late phases of APs, prolonged QT-intervals, and low heart rates without no effect on insulin resistance. In vivo insulin treatment provided also significant recovery in increased PKG and decreased PIP2 level, without the insulin effect on the KCNQ1 level in β3 -ARs overexpressed cells. The inhibition of IKs in aged-rat cardiomyocytes seems to be associated with activated β3 -ARs dependent remodeling in the interaction between KCNQ1 and KCNE1. Significant recoveries in ventricular-repolarization of insulin-treated aged cardiomyocytes via recovery in IKs strongly emphasize two important issues: (1) IKs can be a novel target in aging-associated remodeling in the heart and insulin may be a cardioprotective agent in the maintenance of normal heart function during the aging process. (2) This study is one of the first to demonstrate insulin's benefits on long-QT in insulin-resistant aged rats by accelerating the ventricular AP repolarization through reversing the depressed IKs via affecting the β3 -ARs signaling pathway and particularly affecting activated PKG.
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Affiliation(s)
- Yusuf Olgar
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Aysegul Durak
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | | | - Erkan Tuncay
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey
| | - Belma Turan
- Department of Biophysics, Faculty of Medicine, Ankara University, Ankara, Turkey.,Department of Biophysics, Faculty of Medicine, Lokman Hekim University, Ankara, Turkey
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Cannarella R, Barbagallo F, Condorelli RA, Gusmano C, Crafa A, La Vignera S, Calogero AE. Erectile Dysfunction in Diabetic Patients: From Etiology to Management. DIABETOLOGY 2021; 2:157-164. [DOI: 10.3390/diabetology2030014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
Diabetes mellitus (DM) is a widespread chronic disease with a prevalence that is expected to further increase in the near future. The classical management of DM includes the normalization of the glycometabolic profile and the evaluation of cardiac and cerebral vascular health by the intervention of an array of different specialists. However, so far, sexual dysfunctions are still a neglected complication in patients with DM, although there is an elevated prevalence of this long-term complication in male and female patients. Furthermore, some of them may represent a sign of vascular alteration and/or hypogonadism and require timely management to prevent the onset of major adverse cardiac events. This narrative review briefly summarizes the current evidence on epidemiology, pathogenesis, diagnosis, and therapy of erectile dysfunction in male patients with DM to support diabetologists in clinical practice.
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11
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Kilanowska A, Ziółkowska A. Role of Phosphodiesterase in the Biology and Pathology of Diabetes. Int J Mol Sci 2020; 21:E8244. [PMID: 33153226 PMCID: PMC7662747 DOI: 10.3390/ijms21218244] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 12/12/2022] Open
Abstract
Glucose metabolism is the initiator of a large number of molecular secretory processes in β cells. Cyclic nucleotides as a second messenger are the main physiological regulators of these processes and are functionally divided into compartments in pancreatic cells. Their intracellular concentration is limited by hydrolysis led by one or more phosphodiesterase (PDE) isoenzymes. Literature data confirmed multiple expressions of PDEs subtypes, but the specific roles of each in pancreatic β-cell function, particularly in humans, are still unclear. Isoforms present in the pancreas are also found in various tissues of the body. Normoglycemia and its strict control are supported by the appropriate release of insulin from the pancreas and the action of insulin in peripheral tissues, including processes related to homeostasis, the regulation of which is based on the PDE- cyclic AMP (cAMP) signaling pathway. The challenge in developing a therapeutic solution based on GSIS (glucose-stimulated insulin secretion) enhancers targeted at PDEs is the selective inhibition of their activity only within β cells. Undeniably, PDEs inhibitors have therapeutic potential, but some of them are burdened with certain adverse effects. Therefore, the chance to use knowledge in this field for diabetes treatment has been postulated for a long time.
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Affiliation(s)
| | - Agnieszka Ziółkowska
- Department of Anatomy and Histology, Collegium Medicum, University of Zielona Gora, Zyty 28, 65-046 Zielona Gora, Poland;
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McNally BD, Moran A, Watt NT, Ashmore T, Whitehead A, Murfitt SA, Kearney MT, Cubbon RM, Murray AJ, Griffin JL, Roberts LD. Inorganic Nitrate Promotes Glucose Uptake and Oxidative Catabolism in White Adipose Tissue Through the XOR-Catalyzed Nitric Oxide Pathway. Diabetes 2020; 69:893-901. [PMID: 32086288 DOI: 10.2337/db19-0892] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 02/07/2020] [Indexed: 11/13/2022]
Abstract
An aging global population combined with sedentary lifestyles and unhealthy diets has contributed to an increasing incidence of obesity and type 2 diabetes. These metabolic disorders are associated with perturbations to nitric oxide (NO) signaling and impaired glucose metabolism. Dietary inorganic nitrate, found in high concentration in green leafy vegetables, can be converted to NO in vivo and demonstrates antidiabetic and antiobesity properties in rodents. Alongside tissues including skeletal muscle and liver, white adipose tissue is also an important physiological site of glucose disposal. However, the distinct molecular mechanisms governing the effect of nitrate on adipose tissue glucose metabolism and the contribution of this tissue to the glucose-tolerant phenotype remain to be determined. Using a metabolomic and stable-isotope labeling approach, combined with transcriptional analysis, we found that nitrate increases glucose uptake and oxidative catabolism in primary adipocytes and white adipose tissue of nitrate-treated rats. Mechanistically, we determined that nitrate induces these phenotypic changes in primary adipocytes through the xanthine oxidoreductase-catalyzed reduction of nitrate to NO and independently of peroxisome proliferator-activated receptor-α. The nitrate-mediated enhancement of glucose uptake and catabolism in white adipose tissue may be a key contributor to the antidiabetic effects of this anion.
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Affiliation(s)
- Ben D McNally
- Medical Research Council - Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, U.K
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, U.K
| | - Amy Moran
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, U.K
| | - Nicole T Watt
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, U.K
| | - Tom Ashmore
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, U.K
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, U.K
| | - Anna Whitehead
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, U.K
| | - Steven A Murfitt
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, U.K
| | - Mark T Kearney
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, U.K
| | - Richard M Cubbon
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, U.K
| | - Andrew J Murray
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, U.K
| | - Julian L Griffin
- Medical Research Council - Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, U.K
- Department of Biochemistry and Cambridge Systems Biology Centre, University of Cambridge, Cambridge, U.K
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, U.K
| | - Lee D Roberts
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of Medicine, University of Leeds, Leeds, U.K.
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13
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Atawia RT, Bunch KL, Toque HA, Caldwell RB, Caldwell RW. Mechanisms of obesity-induced metabolic and vascular dysfunctions. FRONT BIOSCI-LANDMRK 2019; 24:890-934. [PMID: 30844720 PMCID: PMC6689231 DOI: 10.2741/4758] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Obesity has reached epidemic proportions and its prevalence is climbing. Obesity is characterized by hypertrophied adipocytes with a dysregulated adipokine secretion profile, increased recruitment of inflammatory cells, and impaired metabolic homeostasis that eventually results in the development of systemic insulin resistance, a phenotype of type 2 diabetes. Nitric oxide synthase (NOS) is an enzyme that converts L-arginine to nitric oxide (NO), which functions to maintain vascular and adipocyte homeostasis. Arginase is a ureohydrolase enzyme that competes with NOS for L-arginine. Arginase activity/expression is upregulated in obesity, which results in diminished bioavailability of NO, impairing both adipocyte and vascular endothelial cell function. Given the emerging role of NO in the regulation of adipocyte physiology and metabolic capacity, this review explores the interplay between arginase and NO, and their effect on the development of metabolic disorders, cardiovascular diseases, and mitochondrial dysfunction in obesity. A comprehensive understanding of the mechanisms involved in the development of obesity-induced metabolic and vascular dysfunction is necessary for the identification of more effective and tailored therapeutic avenues for their prevention and treatment.
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Affiliation(s)
- Reem T Atawia
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University. Augusta, GA 30904, USA
| | - Katharine L Bunch
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University. Augusta, GA 30904, USA
| | - Haroldo A Toque
- Department of Pharmacology and Toxicology,and Vascular Biology Center, Medical College of Georgia, Augusta University. Augusta, GA 30904, USA
| | - Ruth B Caldwell
- Vascular Biology Center, Medical College of Georgia, Augusta University. Augusta, GA 30904, USA
| | - Robert W Caldwell
- Vascular Biology Center, Medical College of Georgia, Augusta University. Augusta, GA 30904,USA,
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14
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Predictive value of serum soluble corin in the risk of hyperglycemia: A population-based prospective cohort study in China. Clin Chim Acta 2018; 479:138-143. [DOI: 10.1016/j.cca.2018.01.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 12/21/2017] [Accepted: 01/18/2018] [Indexed: 02/02/2023]
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15
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The effects of two different doses of ultraviolet-A light exposure on nitric oxide metabolites and cardiorespiratory outcomes. Eur J Appl Physiol 2018. [PMID: 29516257 PMCID: PMC5959980 DOI: 10.1007/s00421-018-3835-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Purpose The present study investigated different doses of ultraviolet-A (UV-A) light on plasma nitric oxide metabolites and cardiorespiratory variables. Methods Ten healthy male participants completed three experimental conditions, 7 days apart. Participants were exposed to no light (CON); 10 J cm2 (15 min) of UV-A light (UVA10) and 20 J cm2 (30 min) of UV-A light (UVA20) in a randomized order. Plasma nitrite [NO2−] and nitrate [NO3−] concentrations, blood pressure (BP), and heart rate (HR) were recorded before, immediately after exposure and 30 min post-exposure. Whole body oxygen utilization (\documentclass[12pt]{minimal}
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\begin{document}$${{\dot{V}}}{\rm O}_{2}$$\end{document}V˙O2), resting metabolic rate (RMR) and skin temperature were recorded continuously. Results None of the measured parameters changed significantly during CON (all P > 0.05). \documentclass[12pt]{minimal}
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\begin{document}$${{\dot{V}}}{\rm O}_{2}$$\end{document}V˙O2 and RMR were significantly reduced immediately after UVA10 (P < 0.05) despite no change in plasma [NO2−] (P > 0.05). Immediately after exposure to UVA20, plasma [NO2−] was higher (P = 0.014) and \documentclass[12pt]{minimal}
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\begin{document}$${{\dot{V}}}{\rm O}_{2}$$\end{document}V˙O2 and RMR tended to be lower compared to baseline (P = 0.06). There were no differences in [NO2−] or \documentclass[12pt]{minimal}
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\begin{document}$${{\dot{V}}}{\rm O}_{2}$$\end{document}V˙O2 at the 30 min time point in any condition. UV-A exposure did not alter systolic BP, diastolic BP or MAP (all P > 0.05). UV-A light did not alter plasma [NO3−] at any time point (all P > 0.05). Conclusions This study demonstrates that a UV-A dose of 20 J cm2 is necessary to increase plasma [NO2−] although a smaller dose is capable of reducing \documentclass[12pt]{minimal}
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\begin{document}$${{\dot{V}}}{\rm O}_{2}$$\end{document}V˙O2 and RMR at rest. Exposure to UV-A did not significantly reduce BP in this cohort of healthy adults. These data suggest that exposure to sunlight has a meaningful acute impact on metabolic function.
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16
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Kopecka J, Porto S, Lusa S, Gazzano E, Salzano G, Pinzòn-Daza ML, Giordano A, Desiderio V, Ghigo D, De Rosa G, Caraglia M, Riganti C. Zoledronic acid-encapsulating self-assembling nanoparticles and doxorubicin: a combinatorial approach to overcome simultaneously chemoresistance and immunoresistance in breast tumors. Oncotarget 2018; 7:20753-72. [PMID: 26980746 PMCID: PMC4991490 DOI: 10.18632/oncotarget.8012] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 02/16/2016] [Indexed: 02/07/2023] Open
Abstract
The resistance to chemotherapy and the tumor escape from host immunosurveillance are the main causes of the failure of anthracycline-based regimens in breast cancer, where an effective chemo-immunosensitizing strategy is lacking. The clinically used aminobisphosphonate zoledronic acid (ZA) reverses chemoresistance and immunoresistance in vitro. Previously we developed a nanoparticle-based zoledronic acid-containing formulation (NZ) that allowed a higher intratumor delivery of the drug compared with free ZA in vivo. We tested its efficacy in combination with doxorubicin in breast tumors refractory to chemotherapy and immune system recognition as a new combinatorial approach to produce chemo- and immunosensitization. NZ reduced the IC50 of doxorubicin in human and murine chemoresistant breast cancer cells and restored the doxorubicin efficacy against chemo-immunoresistant tumors implanted in immunocompetent mice. By reducing the metabolic flux through the mevalonate pathway, NZ lowered the activity of Ras/ERK1/2/HIF-1α axis and the expression of P-glycoprotein, decreased the glycolysis and the mitochondrial respiratory chain, induced a cytochrome c/caspase 9/caspase 3-dependent apoptosis, thus restoring the direct cytotoxic effects of doxorubicin on tumor cell. Moreover, NZ restored the doxorubicin-induced immunogenic cell death and reversed the tumor-induced immunosuppression due to the production of kynurenine, by inhibiting the STAT3/indoleamine 2,3 dioxygenase axis. These events increased the number of dendritic cells and decreased the number of immunosuppressive T-regulatory cells infiltrating the tumors. Our work proposes the use of nanoparticle encapsulating zoledronic acid as an effective tool overcoming at the same time chemoresistance and immunoresistance in breast tumors, thanks to the effects exerted on tumor cell and tumor-infiltrating immune cells.
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Affiliation(s)
- Joanna Kopecka
- Department of Oncology, University of Turin, Turin, Italy
| | - Stefania Porto
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy
| | - Sara Lusa
- Department of Pharmacy, Federico II University of Naples, Naples, Italy
| | - Elena Gazzano
- Department of Oncology, University of Turin, Turin, Italy
| | - Giuseppina Salzano
- Center for Pharmaceutical Biotechnology and Nanomedicine, Northeastern University, Boston, MA, USA
| | - Martha Leonor Pinzòn-Daza
- Department of Oncology, University of Turin, Turin, Italy.,Universidad del Rosario, Facultad de Ciencias Naturales y Matemáticas, RG in Biochemistry and Biotechnology (BIO-BIO), Bogotá, Colombia
| | - Antonio Giordano
- Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA
| | - Vincenzo Desiderio
- Department of Experimental Medicine, Second University of Naples, Naples, Italy
| | - Dario Ghigo
- Department of Oncology, University of Turin, Turin, Italy
| | - Giuseppe De Rosa
- Department of Pharmacy, Federico II University of Naples, Naples, Italy
| | - Michele Caraglia
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy.,Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA
| | - Chiara Riganti
- Department of Oncology, University of Turin, Turin, Italy
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17
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Wasik AA, Lehtonen S. Glucose Transporters in Diabetic Kidney Disease-Friends or Foes? Front Endocrinol (Lausanne) 2018; 9:155. [PMID: 29686650 PMCID: PMC5900043 DOI: 10.3389/fendo.2018.00155] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 03/22/2018] [Indexed: 12/16/2022] Open
Abstract
Diabetic kidney disease (DKD) is a major microvascular complication of diabetes and a common cause of end-stage renal disease worldwide. DKD manifests as an increased urinary protein excretion (albuminuria). Multiple studies have shown that insulin resistance correlates with the development of albuminuria in non-diabetic and diabetic patients. There is also accumulating evidence that glomerular epithelial cells or podocytes are insulin sensitive and that insulin signaling in podocytes is essential for maintaining normal kidney function. At the cellular level, the mechanisms leading to the development of insulin resistance include mutations in the insulin receptor gene, impairments in the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway, or perturbations in the trafficking of glucose transporters (GLUTs), which mediate the uptake of glucose into cells. Podocytes express several GLUTs, including GLUT1, GLUT2, GLUT3, GLUT4, and GLUT8. Of these, the most studied ones are GLUT1 and GLUT4, both shown to be insulin responsive in podocytes. In the basal state, GLUT4 is preferentially located in perinuclear and cytosolic vesicular structures and to a lesser extent at the plasma membrane. After insulin stimulation, GLUT4 is sorted into GLUT4-containing vesicles (GCVs) that translocate to the plasma membrane. GCV trafficking consists of several steps, including approaching of the GCVs to the plasma membrane, tethering, and docking, after which the lipid bilayers of the GCVs and the plasma membrane fuse, delivering GLUT4 to the cell surface for glucose uptake into the cell. Studies have revealed novel molecular regulators of the GLUT trafficking in podocytes and unraveled unexpected roles for GLUT1 and GLUT4 in the development of DKD, summarized in this review. These findings pave the way for better understanding of the mechanistic pathways associated with the development and progression of DKD and aid in the development of new treatments for this devastating disease.
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18
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Tassone B, Saoncella S, Neri F, Ala U, Brusa D, Magnuson MA, Provero P, Oliviero S, Riganti C, Calautti E. Rictor/mTORC2 deficiency enhances keratinocyte stress tolerance via mitohormesis. Cell Death Differ 2017; 24:731-746. [PMID: 28211872 DOI: 10.1038/cdd.2017.8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 12/19/2016] [Accepted: 12/28/2016] [Indexed: 12/27/2022] Open
Abstract
How metabolic pathways required for epidermal tissue growth and remodeling influence the ability of keratinocytes to survive stressful conditions is still largely unknown. The mechanistic target of rapamycin complex 2 (mTORC2) regulates growth and metabolism of several tissues, but its functions in epidermal cells are poorly defined. Rictor is an adaptor protein essential for mTORC2 activity. To explore the roles of mTORC2 in the epidermis, we have conditionally deleted rictor in mice via K14-Cre-mediated homologous recombination and found that its deficiency causes moderate tissue hypoplasia, reduced keratinocyte proliferation and attenuated hyperplastic response to TPA. Noteworthy, rictor-deficient keratinocytes displayed increased lifespan, protection from senescence, and enhanced tolerance to cellular stressors such as growth factors deprivation, epirubicin and X-ray in vitro and radioresistance in vivo. Rictor-deficient keratinocytes exhibited changes in global gene expression profiles consistent with metabolic alterations and enhanced stress tolerance, a shift in cell catabolic processes from glycids and lipids to glutamine consumption and increased production of mitochondrial reactive oxygen species (ROS). Mechanistically, the resiliency of rictor-deficient epidermal cells relies on these ROS increases, indicating stress resistance via mitohormesis. Thus, our findings reveal a new link between metabolic changes and stress adaptation of keratinocytes centered on mTORC2 activity, with potential implications in skin aging and therapeutic resistance of epithelial tumors.
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Affiliation(s)
- Beatrice Tassone
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | - Stefania Saoncella
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | - Francesco Neri
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy.,Human Genetics Foundation (HuGeF), Turin, Italy
| | - Ugo Ala
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | | | - Mark A Magnuson
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Paolo Provero
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy.,Center for Translational Genomics and Bioinformatics, San Raffaele Scientific Institute, Milan, Italy
| | - Salvatore Oliviero
- Human Genetics Foundation (HuGeF), Turin, Italy.,Department of Life Sciences and System Biology, University of Turin, Turin, Italy
| | - Chiara Riganti
- Department of Oncology, University of Turin, Turin, Italy
| | - Enzo Calautti
- Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
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19
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Effect of phosphodiesterase-5 inhibitors on glycemic control in person with type 2 diabetes mellitus: A systematic review and meta-analysis. JOURNAL OF CLINICAL AND TRANSLATIONAL ENDOCRINOLOGY 2016; 6:50-55. [PMID: 29067241 PMCID: PMC5644434 DOI: 10.1016/j.jcte.2016.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 12/30/2022]
Abstract
Chronic use of phosphodiesterase-5 inhibitors (PDE-5i) has been shown to improve insulin action on muscle glucose uptake by the prolongation of nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/protein kinase (PKG) signalling. Aims As the effects of PDE-5i on glycemic control in person with type 2 diabetes mellitus (T2DM) have not been systematically explored, we conducted a meta-analysis of available randomized controlled trials (RCTs). Methods A literature search was performed through electronic databases including MEDLINE (Pubmed), The Cochrane Library, SCOPUS, Web of Science, CINAHL, www.clinicaltrials.gov and www.clinicaltrialresults.org until April 2016 without language restriction. Studies were included if they met the following criteria: (i) RCTs of the chronic use of PDE-5i compared with placebo or no active treatment in T2DM patients (ii) reporting of HbA1c or glycated haemoglobin or fasting plasma glucose (FPG). Results Four studies involving a total of 198 patients fit into the inclusion criteria. All included studies used the same PDE-5i, sildenafil. Reports of HbA1c were analysed as only one study reported FPG. PDE-5i had no beneficial effect on HbA1c with weighted mean difference (WMD) of 0.17% (95% CI, −0.64 to 0.97). Conclusion This meta-analysis suggests that large and well-controlled studies are warranted to shed light on the effect of PDE-5i on glycemic control in people with type 2 diabetes mellitus.
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20
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Sydow K, Mondon CE, Cooke JP. Insulin resistance: potential role of the endogenous nitric oxide synthase inhibitor ADMA. Vasc Med 2016. [DOI: 10.1191/1358863x05vm604oa] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The insulin resistance syndrome (IRS) is considered to be a new target of risk-reduction therapy. The IRS is a cluster of closely associated and interdependent abnormalities and clinical outcomes that occur more commonly in insulin-resistant/hyperinsulinemic individuals. This syndrome predisposes individuals to type 2 diabetes, cardiovascular diseases, essential hypertension, certain forms of cancer, polycystic ovary syndrome, nonalcoholic fatty liver disease, and sleep apnea. In patients at high risk for cardiovascular diseases, endothelial dysfunction is observed in morphologically intact vessels even before the onset of clinically manifest vascular disease. Indeed, there are several lines of evidence that indicate that endothelial function is compromised in situations where there is reduced sensitivity to endogenous insulin. It is well established that a decreased bioavailability of nitric oxide (NO) contributes to endothelial dysfunction. Furthermore, NO may modulate insulin sensitivity. Activation of NO synthase (NOS) augments blood flow to insulin-sensitive tissues (i.e. skeletal muscle, liver, adipose tissue), and its activity is impaired in insulin resistance. Inhibition of NOS reduces the microvascular delivery of nutrients and blunts insulin-stimulated glucose uptake in skeletal muscle. Furthermore, induction of hypertension by administration of the NOS inhibitor NG-monomethyl-L-arginine is also associated with insulin resistance in rats. Increased levels of asymmetric dimethylarginine (ADMA) are associated with endothelial vasodilator dysfunction and increased risk of cardiovascular diseases. An intriguing relationship exists between insulin resistance and ADMA. Plasma levels of ADMA are positively correlated with insulin resistance in nondiabetic, normotensive people. New basic research insights that provide possible mechanisms underlying the development of insulin resistance in the setting of impaired NO bioavailability will be discussed.
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Affiliation(s)
- Karsten Sydow
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA,
| | - Carl E Mondon
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - John P Cooke
- Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA
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21
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Kopecka J, Porto S, Lusa S, Gazzano E, Salzano G, Giordano A, Desiderio V, Ghigo D, Caraglia M, De Rosa G, Riganti C. Self-assembling nanoparticles encapsulating zoledronic acid revert multidrug resistance in cancer cells. Oncotarget 2016; 6:31461-78. [PMID: 26372812 PMCID: PMC4741618 DOI: 10.18632/oncotarget.5058] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 08/27/2015] [Indexed: 01/23/2023] Open
Abstract
The overexpression of ATP binding cassette (ABC) transporters makes tumor cells simultaneously resistant to several cytotoxic drugs. Impairing the energy metabolism of multidrug resistant (MDR) cells is a promising chemosensitizing strategy, but many metabolic modifiers are too toxic in vivo. We previously observed that the aminobisphosphonate zoledronic acid inhibits the activity of hypoxia inducible factor-1α (HIF-1α), a master regulator of cancer cell metabolism. Free zoledronic acid, however, reaches low intratumor concentration. We synthesized nanoparticle formulations of the aminobisphosphonate that allow a higher intratumor delivery of the drug. We investigated whether they are effective metabolic modifiers and chemosensitizing agents against human MDR cancer cells in vitro and in vivo. At not toxic dosage, nanoparticles carrying zoledronic acid chemosensitized MDR cells to a broad spectrum of cytotoxic drugs, independently of the type of ABC transporters expressed. The nanoparticles inhibited the isoprenoid synthesis and the Ras/ERK1/2-driven activation of HIF-1α, decreased the transcription and activity of glycolytic enzymes, the glucose flux through the glycolysis and tricarboxylic acid cycle, the electron flux through the mitochondrial respiratory chain, the synthesis of ATP. So doing, they lowered the ATP-dependent activity of ABC transporters, increasing the chemotherapy efficacy in vitro and in vivo. These effects were more pronounced in MDR cells than in chemosensitive ones and were due to the inhibition of farnesyl pyrophosphate synthase (FPPS), as demonstrated in FPPS-silenced tumors. Our work proposes nanoparticle formulations of zoledronic acid as the first not toxic metabolic modifiers, effective against MDR tumors.
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Affiliation(s)
- Joanna Kopecka
- Department of Oncology, University of Torino, Torino, Italy
| | - Stefania Porto
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy
| | - Sara Lusa
- Department of Pharmacy, Federico II University of Naples, Naples, Italy
| | - Elena Gazzano
- Department of Oncology, University of Torino, Torino, Italy
| | - Giuseppina Salzano
- Center for Pharmaceutical Biotechnology and Nanomedicine, Northeastern University, Boston, MA, USA
| | - Antonio Giordano
- Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA.,Department of Medicine, Surgery and Neuroscience University of Siena, Siena, Italy
| | - Vincenzo Desiderio
- Department of Experimental Medicine, Second University of Naples, Naples, Italy
| | - Dario Ghigo
- Department of Oncology, University of Torino, Torino, Italy
| | - Michele Caraglia
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Naples, Italy.,Sbarro Institute for Cancer Research and Molecular Medicine, Center for Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA
| | - Giuseppe De Rosa
- Department of Pharmacy, Federico II University of Naples, Naples, Italy
| | - Chiara Riganti
- Department of Oncology, University of Torino, Torino, Italy
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22
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Pereira TMC, Pimenta FS, Porto ML, Baldo MP, Campagnaro BP, Gava AL, Meyrelles SS, Vasquez EC. Coadjuvants in the Diabetic Complications: Nutraceuticals and Drugs with Pleiotropic Effects. Int J Mol Sci 2016; 17:ijms17081273. [PMID: 27527163 PMCID: PMC5000671 DOI: 10.3390/ijms17081273] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 07/27/2016] [Accepted: 07/29/2016] [Indexed: 12/19/2022] Open
Abstract
Because diabetes mellitus (DM) is a multifactorial metabolic disease, its prevention and treatment has been a constant challenge for basic and clinical investigators focused on translating their discoveries into clinical treatment of this complex disorder. In this review, we highlight recent experimental and clinical evidences of potential coadjuvants in the management of DM, such as polyphenols (quercetin, resveratrol and silymarin), cultured probiotic microorganisms and drugs acting through direct/indirect or pleiotropic effects on glycemic control in DM. Among several options, we highlight new promising therapeutic coadjuvants, including chemical scavengers, the probiotic kefir and the phosphodiesterase 5 inhibitors, which besides the reduction of hyperglycemia and ameliorate insulin resistance, they reduce oxidative stress and improve endothelial dysfunction in the systemic vascular circulation. In the near future, experimental studies are expected to clear the intracellular pathways involving coadjuvants. The design of clinical trials may also contribute to new strategies with coadjuvants against the harmful effects of diabetic complications.
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Affiliation(s)
- Thiago Melo Costa Pereira
- Pharmaceutical Sciences Graduate Program, Vila Velha University (UVV), Av. Comissario Jose Dantas Melo 21, Boa Vista, 29102-920 Vila Velha, Brazil.
- Federal Institute of Education, Science and Technology (IFES), 29106-010 Vila Velha, Brazil.
| | - Fabio Silva Pimenta
- Pharmaceutical Sciences Graduate Program, Vila Velha University (UVV), Av. Comissario Jose Dantas Melo 21, Boa Vista, 29102-920 Vila Velha, Brazil.
- Burn Treatment Center, Children State Hospital, 29056-030 Vitoria, Brazil.
| | - Marcella Lima Porto
- Federal Institute of Education, Science and Technology (IFES), 29106-010 Vila Velha, Brazil.
| | - Marcelo Perim Baldo
- Department of Pathophysiology, Montes Claros State University, 39401-089, Montes Claros, Brazil.
| | - Bianca Prandi Campagnaro
- Pharmaceutical Sciences Graduate Program, Vila Velha University (UVV), Av. Comissario Jose Dantas Melo 21, Boa Vista, 29102-920 Vila Velha, Brazil.
| | - Agata Lages Gava
- Laboratory of Translational Physiology, Federal University of Espirito Santo (Ufes), 29047-100 Vitoria, Brazil.
- Division of Nephrology, McMaster University, Hamilton, ON L8N 4A6, Canada.
| | - Silvana Santos Meyrelles
- Laboratory of Translational Physiology, Federal University of Espirito Santo (Ufes), 29047-100 Vitoria, Brazil.
| | - Elisardo Corral Vasquez
- Pharmaceutical Sciences Graduate Program, Vila Velha University (UVV), Av. Comissario Jose Dantas Melo 21, Boa Vista, 29102-920 Vila Velha, Brazil.
- Laboratory of Translational Physiology, Federal University of Espirito Santo (Ufes), 29047-100 Vitoria, Brazil.
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Harith HH, Di Bartolo BA, Cartland SP, Genner S, Kavurma MM. Insulin promotes vascular smooth muscle cell proliferation and apoptosis via differential regulation of tumor necrosis factor-related apoptosis-inducing ligand. J Diabetes 2016; 8:568-78. [PMID: 26333348 DOI: 10.1111/1753-0407.12339] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 08/12/2015] [Accepted: 08/29/2015] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Insulin regulates glucose homeostasis but can also promote vascular smooth muscle (VSMC) proliferation, important in atherogenesis. Recently, we showed that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) stimulates intimal thickening via accelerated growth of VSMCs. The aim of the present study was to determine whether insulin-induced effects on VSMCs occur via TRAIL. METHODS Expression of TRAIL and TRAIL receptor in response to insulin and glucose was determined by polymerase chain reaction. Transcriptional activity was assessed using wild-type and site-specific mutations of the TRAIL promoter. Chromatin immunoprecipitation studies were performed. VSMC proliferation and apoptosis was measured. RESULTS Insulin and glucose exposure to VSMC for 24 h stimulated TRAIL mRNA expression. This was also evident at the transcriptional level. Both insulin- and glucose-inducible TRAIL transcriptional activity was blocked by dominant-negative specificity protein-1 (Sp1) overexpression. There are five functional Sp1-binding elements (Sp1-1, Sp1-2, Sp-5/6 and Sp1-7) on the TRAIL promoter. Insulin required the Sp1-1 and Sp1-2 sites, but glucose needed all Sp1-binding sites to induce transcription. Furthermore, insulin (but not glucose) was able to promote VSMC proliferation over time, associated with increased decoy receptor-2 (DcR2) expression. In contrast, chronic 5-day exposure of VSMC to 1 µg/mL insulin repressed TRAIL and DcR2 expression, and reduced Sp1 enrichment on the TRAIL promoter. This was associated with increased cell death. CONCLUSIONS The findings of the present study provide a new mechanistic insight into how TRAIL is regulated by insulin. This may have significant implications at different stages of diabetes-associated cardiovascular disease. Thus, TRAIL may offer a novel therapeutic solution to combat insulin-induced vascular pathologies.
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MESH Headings
- Animals
- Apoptosis/drug effects
- Blotting, Western
- Cell Proliferation/drug effects
- Cells, Cultured
- Dose-Response Relationship, Drug
- Gene Expression Regulation/drug effects
- Glucose/pharmacology
- Humans
- Hypoglycemic Agents/pharmacology
- Insulin/pharmacology
- Mice, Knockout
- Muscle, Smooth, Vascular/cytology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Rats, Inbred WKY
- Receptors, TNF-Related Apoptosis-Inducing Ligand/genetics
- Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- TNF-Related Apoptosis-Inducing Ligand/genetics
- TNF-Related Apoptosis-Inducing Ligand/metabolism
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Affiliation(s)
- Hanis H Harith
- Centre for Vascular Research
- School of Medical Sciences UNSW, Australia
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia
| | - Belinda A Di Bartolo
- The Heart Research Institute
- The University of Sydney, Sydney, New South Wales, Australia
| | - Siân P Cartland
- The Heart Research Institute
- The University of Sydney, Sydney, New South Wales, Australia
| | | | - Mary M Kavurma
- The Heart Research Institute
- The University of Sydney, Sydney, New South Wales, Australia
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24
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Mondal D, Mathur A, Chandra PK. Tripping on TRIB3 at the junction of health, metabolic dysfunction and cancer. Biochimie 2016; 124:34-52. [DOI: 10.1016/j.biochi.2016.02.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 02/04/2016] [Indexed: 12/16/2022]
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25
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Wellhauser L, Chalmers JA, Belsham DD. Nitric Oxide Exerts Basal and Insulin-Dependent Anorexigenic Actions in POMC Hypothalamic Neurons. Mol Endocrinol 2016; 30:402-16. [PMID: 26930171 DOI: 10.1210/me.2015-1275] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The arcuate nucleus of the hypothalamus represents a key center for the control of appetite and feeding through the regulation of 2 key neuronal populations, notably agouti-related peptide/neuropeptide Y and proopimelanocortin (POMC)/cocaine- and amphetamine-regulated transcript neurons. Altered regulation of these neuronal networks, in particular the dysfunction of POMC neurons upon high-fat consumption, is a major pathogenic mechanism involved in the development of obesity and type 2 diabetes mellitus. Efforts are underway to preserve the integrity or enhance the functionality of POMC neurons in order to prevent or treat these metabolic diseases. Here, we report for the first time that the nitric oxide (NO(-)) donor, sodium nitroprusside (SNP) mediates anorexigenic actions in both hypothalamic tissue and hypothalamic-derived cell models by mediating the up-regulation of POMC levels. SNP increased POMC mRNA in a dose-dependent manner and enhanced α-melanocortin-secreting hormone production and secretion in mHypoA-POMC/GFP-2 cells. SNP also enhanced insulin-driven POMC expression likely by inhibiting the deacetylase activity of sirtuin 1. Furthermore, SNP enhanced insulin-dependent POMC expression, likely by reducing the transcriptional repression of Foxo1 on the POMC gene. Prolonged SNP exposure prevented the development of insulin resistance. Taken together, the NO(-) donor SNP enhances the anorexigenic potential of POMC neurons by promoting its transcriptional expression independent and in cooperation with insulin. Thus, increasing cellular NO(-) levels represents a hormone-independent method of promoting anorexigenic output from the existing POMC neuronal populations and may be advantageous in the fight against these prevalent disorders.
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Affiliation(s)
- Leigh Wellhauser
- Department of Physiology (L.W., J.A.C., D.D.B.), University of Toronto, Toronto, Ontario, Canada M5G 1A8; and Departments of Obstetrics, Gynaecology, and Medicine (D.D.B.), University of Toronto and Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada M5S 1A8
| | - Jennifer A Chalmers
- Department of Physiology (L.W., J.A.C., D.D.B.), University of Toronto, Toronto, Ontario, Canada M5G 1A8; and Departments of Obstetrics, Gynaecology, and Medicine (D.D.B.), University of Toronto and Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada M5S 1A8
| | - Denise D Belsham
- Department of Physiology (L.W., J.A.C., D.D.B.), University of Toronto, Toronto, Ontario, Canada M5G 1A8; and Departments of Obstetrics, Gynaecology, and Medicine (D.D.B.), University of Toronto and Division of Cellular and Molecular Biology, Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada M5S 1A8
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26
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Ramirez CE, Nian H, Yu C, Gamboa JL, Luther JM, Brown NJ, Shibao CA. Treatment with Sildenafil Improves Insulin Sensitivity in Prediabetes: A Randomized, Controlled Trial. J Clin Endocrinol Metab 2015; 100:4533-40. [PMID: 26580240 PMCID: PMC4667163 DOI: 10.1210/jc.2015-3415] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Sildenafil increases insulin sensitivity in mice. In humans, phosphodiesterase 5 inhibition improves disposition index, but the mechanism of this effect has not been elucidated and may depend on duration. In addition, increasing cyclic GMP without increasing nitric oxide could have beneficial effects on fibrinolytic balance. OBJECTIVE The objective was to test the hypothesis that chronic phosphodiesterase 5 inhibition with sildenafil improves insulin sensitivity and secretion without diminishing fibrinolytic function. DESIGN This was a randomized, double-blind, placebo-controlled study. SETTING This trial was conducted at Vanderbilt Clinical Research Center. PARTICIPANTS Participants included overweight individuals with prediabetes. INTERVENTIONS Subjects were randomized to treatment with sildenafil 25 mg three times a day or matching placebo for 3 months. Subjects underwent a hyperglycemic clamp prior to and at the end of treatment. MAIN OUTCOME MEASURES The primary outcomes of the study were insulin sensitivity and glucose-stimulated insulin secretion. RESULT Twenty-one subjects completed each treatment arm. After 3 months, the insulin sensitivity index was significantly greater in the sildenafil group compared to the placebo group by 1.84 mg/kg/min per μU/mL*100 (95% confidence interval, 0.01 to 3.67 mg/kg/min per μU/mL*100; P = .049), after adjusting for baseline insulin sensitivity index and body mass index. In contrast, there was no effect of 3-month treatment with sildenafil on acute- or late-phase glucose-stimulated insulin secretion (P > .30). Sildenafil decreased plasminogen activator inhibitor-1 (P = .01), without altering tissue-plasminogen activator. In contrast to placebo, sildenafil also decreased the urine albumin-to-creatinine ratio from 12.67 ± 14.67 to 6.84 ± 4.86 μg/mg Cr. This effect persisted 3 months after sildenafil discontinuation. CONCLUSIONS Three-month phosphodiesterase 5 inhibition enhances insulin sensitivity and improves markers of endothelial function.
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Affiliation(s)
- Claudia E Ramirez
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Hui Nian
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Chang Yu
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Jorge L Gamboa
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - James M Luther
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Nancy J Brown
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
| | - Cyndya A Shibao
- Departments of Medicine (C.E.R., J.L.G., J.M.L., N.J.B., C.A.S.) and Biostatistics (H.N., C.Y.), Vanderbilt University School of Medicine, Nashville, Tennessee 37232
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27
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Sottero B, Gargiulo S, Russo I, Barale C, Poli G, Cavalot F. Postprandial Dysmetabolism and Oxidative Stress in Type 2 Diabetes: Pathogenetic Mechanisms and Therapeutic Strategies. Med Res Rev 2015; 35:968-1031. [PMID: 25943420 DOI: 10.1002/med.21349] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Postprandial dysmetabolism in type 2 diabetes (T2D) is known to impact the progression and evolution of this complex disease process. However, the underlying pathogenetic mechanisms still require full elucidation to provide guidance for disease prevention and treatment. This review focuses on the marked redox changes and inflammatory stimuli provoked by the spike in blood glucose and lipids in T2D individuals after meals. All the causes of exacerbated postprandial oxidative stress in T2D were analyzed, also considering the consequence of enhanced inflammation on vascular damage. Based on this in-depth analysis, current strategies of prevention and pharmacologic management of T2D were critically reexamined with particular emphasis on their potential redox-related rationale.
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Affiliation(s)
- Barbara Sottero
- Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Orbassano, Turin, 10043, Italy
| | - Simona Gargiulo
- Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Orbassano, Turin, 10043, Italy
| | - Isabella Russo
- Internal Medicine and Metabolic Disease Unit, Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Orbassano, Turin, 10043, Italy
| | - Cristina Barale
- Internal Medicine and Metabolic Disease Unit, Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Orbassano, Turin, 10043, Italy
| | - Giuseppe Poli
- Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Orbassano, Turin, 10043, Italy
| | - Franco Cavalot
- Internal Medicine and Metabolic Disease Unit, Department of Clinical and Biological Sciences, University of Turin, San Luigi Gonzaga Hospital, Orbassano, Turin, 10043, Italy
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28
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Atkins KB, Seki Y, Saha J, Eichinger F, Charron MJ, Brosius FC. Maintenance of GLUT4 expression in smooth muscle prevents hypertension-induced changes in vascular reactivity. Physiol Rep 2015; 3:3/2/e12299. [PMID: 25677552 PMCID: PMC4393207 DOI: 10.14814/phy2.12299] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Previous studies have shown that expression of GLUT4 is decreased in arterial smooth muscle of hypertensive rats and mice and that total body overexpression of GLUT4 in mice prevents enhanced arterial reactivity in hypertension. To demonstrate that the effect of GLUT4 overexpression on vascular responses is dependent on vascular smooth muscle GLUT4 rather than on some systemic effect we developed and tested smooth-muscle-specific GLUT4 transgenic mice (SMG4). When made hypertensive with angiotensin II, both wild-type and SMG4 mice exhibited similarly increased systolic blood pressure. Responsiveness to phenylephrine, serotonin, and prostaglandin F2α was significantly increased in endothelium-intact aortic rings from hypertensive wild-type mice but not in aortae of SMG4 mice. Inhibition of Rho-kinase equally reduced serotonin-stimulated contractility in aortae of hypertensive wild-type and SMG4-mice. In addition, acetylcholine-stimulated relaxation was significantly decreased in aortic rings of hypertensive wild-type mice, but not in rings of SMG4 mice. Inhibition of either prostacylin receptors or cyclooxygenase-2 reduced relaxation in rings of hypertensive SMG4 mice. Inhibition of cyclooxygenase-2 had no effect on relaxation in rings of hypertensive wild-type mice. Cyclooxygenase-2 protein expression was decreased in hypertensive wild-type aortae but not in hypertensive SMG4 aortae compared to nonhypertensive controls. Our results demonstrate that smooth muscle expression of GLUT4 exerts a major effect on smooth muscle contractile responses and endothelium-dependent vasorelaxation and that normal expression of GLUT4 in vascular smooth muscle is required for appropriate smooth muscle and endothelial responses.
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Affiliation(s)
- Kevin B Atkins
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Yoshinori Seki
- Department of Biochemistry, Albert Einstein College of Medicine, New York City, New York, USA
| | - Jharna Saha
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Felix Eichinger
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Maureen J Charron
- Department of Biochemistry, Albert Einstein College of Medicine, New York City, New York, USA Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, New York City, New York, USA Medicine, Albert Einstein College of Medicine, New York City, New York, USA
| | - Frank C Brosius
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA Department of Physiology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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29
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Chang CF, Diers AR, Hogg N. Cancer cell metabolism and the modulating effects of nitric oxide. Free Radic Biol Med 2015; 79:324-36. [PMID: 25464273 PMCID: PMC5275750 DOI: 10.1016/j.freeradbiomed.2014.11.012] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Revised: 10/31/2014] [Accepted: 11/08/2014] [Indexed: 12/18/2022]
Abstract
Altered metabolic phenotype has been recognized as a hallmark of tumor cells for many years, but this aspect of the cancer phenotype has come into greater focus in recent years. NOS2 (inducible nitric oxide synthase of iNOS) has been implicated as a component in many aggressive tumor phenotypes, including melanoma, glioblastoma, and breast cancer. Nitric oxide has been well established as a modulator of cellular bioenergetics pathways, in many ways similar to the alteration of cellular metabolism observed in aggressive tumors. In this review we attempt to bring these concepts together with the general hypothesis that one function of NOS2 and NO in cancer is to modulate metabolic processes to facilitate increased tumor aggression. There are many mechanisms by which NO can modulate tumor metabolism, including direct inhibition of respiration, alterations in mitochondrial mass, oxidative inhibition of bioenergetic enzymes, and the stimulation of secondary signaling pathways. Here we review metabolic alterations in the context of cancer cells and discuss the role of NO as a potential mediator of these changes.
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Affiliation(s)
- Ching-Fang Chang
- Department of Biophysics and Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Anne R Diers
- Department of Biophysics and Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | - Neil Hogg
- Department of Biophysics and Redox Biology Program, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
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30
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Lin C, Lin CN, Wang YC, Liu FY, Chien YW, Chuang YJ, Lan CY, Hsieh WP, Chen BS. Robustness analysis on interspecies interaction network for iron and glucose competition between Candida albicans and zebrafish during infection. BMC SYSTEMS BIOLOGY 2014; 8 Suppl 5:S6. [PMID: 25603810 PMCID: PMC4305985 DOI: 10.1186/1752-0509-8-s5-s6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Candida albicans has emerged as an important model organism for the study of infectious disease. Using high-throughput simultaneously quantified time-course transcriptomics, this study constructed host-pathogen interspecies interaction networks between C. albicans and zebrafish during the adhesion, invasion, and damage stages. Given that iron and glucose have been identified as crucial resources required during the infection process between C. albicans and zebrafish, we focused on the construction of the interspecies networks associated with them. Furthermore, a randomization technique was proposed to identify differentially regulated proteins that are statistically eminent for the three infection stages. The behaviors of the highly connected or differentially regulated proteins identified from the resulting networks were further investigated. "Robustness" is an important system property that measures the ability of the system tolerating the intrinsic perturbations in a dynamic network. This characteristic provides a systematic and quantitative view to elucidate the dynamics of iron and glucose competition in terms of the interspecies interaction networks. Here, we further estimated the robustness of our constructed interspecies interaction networks for the three infection stages. The constructed networks and robustness analysis provided significant insight into dynamic interactions related to iron and glucose competition during infection and enabled us to quantify the system's intrinsic perturbation tolerance ability during iron and glucose competition throughout the three infection stages. Moreover, the networks also assist in elucidating the offensive and defensive mechanisms of C. albicans and zebrafish during their competition for iron and glucose. Our proposed method can be easily extended to identify other such networks involved in the competition for essential resources during infection.
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31
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Plante E, Menaouar A, Danalache BA, Broderick TL, Jankowski M, Gutkowska J. Treatment with brain natriuretic peptide prevents the development of cardiac dysfunction in obese diabetic db/db mice. Diabetologia 2014; 57:1257-67. [PMID: 24595856 DOI: 10.1007/s00125-014-3201-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 02/03/2014] [Indexed: 12/21/2022]
Abstract
AIMS/HYPOTHESIS Obesity and diabetes increase the risk of developing cardiovascular diseases and heart failure. These metabolic disorders are generally reflected by natriuretic peptide system deficiency. Since brain natriuretic peptide (BNP) is known to influence metabolism and cardioprotection, we investigated the effect of chronic exogenous BNP treatment on adverse myocardial consequences related to obesity and diabetes. METHODS Ten-week-old C57BL/KsJ-db/db obese diabetic mice (db/db) and their lean control littermates (db/+) were treated with BNP (0.6 μg kg(-1) h(-1)) or saline for 12 weeks (n = 10/group). Serial blood and tomography analysis were performed. Cardiac function was determined by echocardiography, and biochemical and histological heart and fat analyses were also performed. RESULTS BNP treatment resulted in an average increase in plasma BNP levels of 70 pg/ml. An improvement in the metabolic profile of db/db mice was observed, including a reduction in fat content, increased insulin sensitivity, improved glucose tolerance and lower blood glucose, despite increased food intake. db/db mice receiving saline displayed both early systolic and diastolic dysfunction, whereas these functional changes were prevented by BNP treatment. The cardioprotective effects of BNP were attributed to the inhibition of cardiomyocyte apoptosis, myocardial fibrosis, cardiac hypertrophy and the AGE-receptor for AGE (RAGE) system as well as normalisation of cardiac AMP-activated protein kinase and endothelial nitric oxide synthase activities. CONCLUSIONS/INTERPRETATION Our results indicate that chronic BNP treatment at low dose improves the metabolic profile and prevents the development of myocardial dysfunction in db/db mice.
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Affiliation(s)
- Eric Plante
- Cardiovascular Biochemistry Laboratory, CRCHUM (7-134), Tour Viger, 900 St-Denis St., Montreal, Quebec, H2X 0A9, Canada
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32
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Barvitenko NN, Aslam M, Filosa J, Matteucci E, Nikinmaa M, Pantaleo A, Saldanha C, Baskurt OK. Tissue oxygen demand in regulation of the behavior of the cells in the vasculature. Microcirculation 2014; 20:484-501. [PMID: 23441854 DOI: 10.1111/micc.12052] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 02/19/2013] [Indexed: 12/20/2022]
Abstract
The control of arteriolar diameters in microvasculature has been in the focus of studies on mechanisms matching oxygen demand and supply at the tissue level. Functionally, important vascular elements include EC, VSMC, and RBC. Integration of these different cell types into functional units aimed at matching tissue oxygen supply with tissue oxygen demand is only achieved when all these cells can respond to the signals of tissue oxygen demand. Many vasoactive agents that serve as signals of tissue oxygen demand have their receptors on all these types of cells (VSMC, EC, and RBC) implying that there can be a coordinated regulation of their behavior by the tissue oxygen demand. Such functions of RBC as oxygen carrying by Hb, rheology, and release of vasoactive agents are considered. Several common extra- and intracellular signaling pathways that link tissue oxygen demand with control of VSMC contractility, EC permeability, and RBC functioning are discussed.
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Insulin stimulates glucose transport via protein kinase G type I alpha-dependent pathway in podocytes. Biochem Biophys Res Commun 2014; 446:328-34. [PMID: 24602613 DOI: 10.1016/j.bbrc.2014.02.108] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 02/24/2014] [Indexed: 01/09/2023]
Abstract
Podocyte resistance to the actions of insulin on glucose transport could contribute to the pathogenesis of diabetic podocytopathy (DP) via disturbances in cyclic-dependent protein kinase signaling. To determine whether cGMP-dependent protein kinase (PKG) is involved in the insulin regulation of glucose transport, we measured insulin-dependent glucose uptake into cultured rat podocytes under conditions of modified PKG activity using pharmacological (PKG activator or inhibitor) and biochemical (siRNA PKGIα, siRNA insulin receptor β) means. Our findings indicate the participation of PKG in insulin-stimulated transport and provide new insights into how PKG may trigger the resistance of glucose transport to insulin in DP.
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34
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Guzmán-Gutiérrez E, Arroyo P, Salsoso R, Fuenzalida B, Sáez T, Leiva A, Pardo F, Sobrevia L. Role of Insulin and Adenosine in the Human Placenta Microvascular and Macrovascular Endothelial Cell Dysfunction in Gestational Diabetes Mellitus. Microcirculation 2014; 21:26-37. [DOI: 10.1111/micc.12077] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Accepted: 07/18/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Enrique Guzmán-Gutiérrez
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Pablo Arroyo
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Rocío Salsoso
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Bárbara Fuenzalida
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
- Biomedical Department; Faculty of Health Sciences; Universidad de Antofagasta; Antofagasta Chile
| | - Tamara Sáez
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Andrea Leiva
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Fabián Pardo
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
| | - Luis Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL); Division of Obstetrics and Gynaecology; Medical Research Centre (CIM); School of Medicine; Faculty of Medicine; Pontificia Universidad Católica de Chile; Santiago Chile
- University of Queensland Centre for Clinical Research; Herston Queensland Australia
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Nicolson GL, Ash ME. Lipid Replacement Therapy: a natural medicine approach to replacing damaged lipids in cellular membranes and organelles and restoring function. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1838:1657-79. [PMID: 24269541 DOI: 10.1016/j.bbamem.2013.11.010] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2013] [Revised: 10/30/2013] [Accepted: 11/09/2013] [Indexed: 12/14/2022]
Abstract
Lipid Replacement Therapy, the use of functional oral supplements containing cell membrane phospholipids and antioxidants, has been used to replace damaged, usually oxidized, membrane glycerophospholipids that accumulate during aging and in various clinical conditions in order to restore cellular function. This approach differs from other dietary and intravenous phospholipid interventions in the composition of phospholipids and their defense against oxidation during storage, ingestion, digestion and uptake as well as the use of protective molecules that noncovalently complex with phospholipid micelles and prevent their enzymatic and bile disruption. Once the phospholipids have been taken in by transport processes, they are protected by several natural mechanisms involving lipid receptors, transport and carrier molecules and circulating cells and lipoproteins until their delivery to tissues and cells where they can again be transferred to intracellular membranes by specific and nonspecific transport systems. Once delivered to membrane sites, they naturally replace and stimulate removal of damaged membrane lipids. Various chronic clinical conditions are characterized by membrane damage, mainly oxidative but also enzymatic, resulting in loss of cellular function. This is readily apparent in mitochondrial inner membranes where oxidative damage to phospholipids like cardiolipin and other molecules results in loss of trans-membrane potential, electron transport function and generation of high-energy molecules. Recent clinical trials have shown the benefits of Lipid Replacement Therapy in restoring mitochondrial function and reducing fatigue in aged subjects and patients with a variety of clinical diagnoses that are characterized by loss of mitochondrial function and include fatigue as a major symptom. This Article is Part of a Special Issue Entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
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Affiliation(s)
- Garth L Nicolson
- Department of Molecular Pathology, The Institute for Molecular Medicine, Huntington Beach, CA 92649, USA.
| | - Michael E Ash
- Clinical Education, Newton Abbot, Devon TQ12 4SG, UK
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Law WHT, Lee LCC, Louie MW, Liu HW, Ang TWH, Lo KKW. Phosphorescent Cellular Probes and Uptake Indicators Derived from Cyclometalated Iridium(III) Bipyridine Complexes Appended with a Glucose or Galactose Entity. Inorg Chem 2013; 52:13029-41. [DOI: 10.1021/ic401714p] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Wendell Ho-Tin Law
- Institute of Molecular Functional
Materials [Areas of Excellence Scheme, University Grants Committee
(Hong Kong)] and Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P. R. China
| | - Lawrence Cho-Cheung Lee
- Institute of Molecular Functional
Materials [Areas of Excellence Scheme, University Grants Committee
(Hong Kong)] and Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P. R. China
| | - Man-Wai Louie
- Institute of Molecular Functional
Materials [Areas of Excellence Scheme, University Grants Committee
(Hong Kong)] and Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P. R. China
| | - Hua-Wei Liu
- Institute of Molecular Functional
Materials [Areas of Excellence Scheme, University Grants Committee
(Hong Kong)] and Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P. R. China
| | - Tim Wai-Hung Ang
- Institute of Molecular Functional
Materials [Areas of Excellence Scheme, University Grants Committee
(Hong Kong)] and Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P. R. China
| | - Kenneth Kam-Wing Lo
- Institute of Molecular Functional
Materials [Areas of Excellence Scheme, University Grants Committee
(Hong Kong)] and Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, P. R. China
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Velázquez E, Blázquez E, Ruiz-Albusac JM. Glucagon-like peptide-2 (GLP-2) modulates the cGMP signalling pathway by regulating the expression of the soluble guanylyl cyclase receptor subunits in cultured rat astrocytes. Mol Neurobiol 2012; 46:242-50. [PMID: 22806360 DOI: 10.1007/s12035-012-8298-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 06/26/2012] [Indexed: 01/23/2023]
Abstract
The aim of this work was to study the effect of glucagon-like peptide-2 (GLP-2) on the cyclic guanosine monophosphate (cGMP) signalling pathway and whether insulin or epidermal growth factor (EGF) might modulate the effects of GLP-2. GLP-2 produced a dose-dependent decrease in intracellular sodium nitroprusside-induced cGMP production. However, insulin induced an increase in the levels of cGMP that was dose-dependently decreased by the addition of GLP-2. By contrast, EGF induced a decrease in cGMP production, which was further reduced by the addition of GLP-2. To assess whether variations in cGMP production might be related with changes in some component of soluble guanylyl cyclase (sGC), the expression of the α1, α2, and β1 subunits were determined by Western blot analysis. At 1 h, GLP-2 produced a decrease in the expression of both α1 and β1 in the cytosolic fraction, but at 24 h only β1was reduced. As expected, insulin induced an increase in the expression of both subunits after 1 h of incubation; this was decreased by the addition of GLP-2. Likewise, incubation with EGF for 24 h produced a decrease in the expression of both subunits that was maximal when GLP-2 was added. In addition, incubation with insulin for 1 h produced an increase in the expression of the α2 subunit, which was reduced by the addition of GLP-2. These results suggest that GLP-2 inhibits cGMP production by decreasing the cellular content of at least one subunit of the heterodimeric active form of the sGC, independently of the presence of insulin or EFG. This may open new insights into the actions of this neuropeptide.
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Affiliation(s)
- Esther Velázquez
- Department of Biochemistry and Molecular Biology, Complutense University Plaza S. Ramón y Cajal s/n, 28040 Madrid, Spain
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Chao A, Zhang X, Ma D, Langlais P, Luo M, Mandarino LJ, Zingsheim M, Pham K, Dillon J, Yi Z. Site-specific phosphorylation of protein phosphatase 1 regulatory subunit 12A stimulated or suppressed by insulin. J Proteomics 2012; 75:3342-50. [PMID: 22516431 DOI: 10.1016/j.jprot.2012.03.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 03/08/2012] [Accepted: 03/26/2012] [Indexed: 10/28/2022]
Abstract
Protein phosphatase 1 (PP1) is one of the major phosphatases responsible for protein dephosphorylation in eukaryotes. So far, only few specific phosphorylation sites of PP1 regulatory subunit 12A (PPP1R12A) have been shown to regulate the PP1 activity. The effect of insulin on PPP1R12A phosphorylation is largely unknown. Utilizing a mass spectrometry based phosphorylation identification and quantification approach, we identified 21 PPP1R12A phosphorylation sites (7 novel sites, including Ser20, Thr22, Thr453, Ser478, Thr671, Ser678, and Ser680) and quantified 16 of them under basal and insulin stimulated conditions in hamster ovary cells overexpressing the insulin receptor (CHO/IR), an insulin sensitive cell model. Insulin stimulated the phosphorylation of PPP1R12A significantly at Ser477, Ser478, Ser507, Ser668, and Ser695, while simultaneously suppressing the phosphorylation of PPP1R12A at Ser509 (more than 2-fold increase or decrease compared to basal). Our data demonstrate that PPP1R12A undergoes insulin stimulated/suppressed phosphorylation, suggesting that PPP1R12A phosphorylation may play a role in insulin signal transduction. The novel PPP1R12A phosphorylation sites as well as the new insulin-responsive phosphorylation sites of PPP1R12A in CHO/IR cells provide targets for investigation of the regulation of PPP1R12A and the PPP1R12A-PP1cδ complex in insulin action and other signaling pathways in other cell models, animal models, and humans.
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Affiliation(s)
- Alex Chao
- Department of Pharmaceutical Sciences, Eugene Applebaum College of Pharmacy/Health Sciences, Wayne State University, Detroit, MI, USA
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Magnusson M, Jujic A, Hedblad B, Engström G, Persson M, Struck J, Morgenthaler NG, Nilsson P, Newton-Cheh C, Wang TJ, Melander O. Low plasma level of atrial natriuretic peptide predicts development of diabetes: the prospective Malmo Diet and Cancer study. J Clin Endocrinol Metab 2012; 97:638-45. [PMID: 22112816 PMCID: PMC3275360 DOI: 10.1210/jc.2011-2425] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT The cardiac natriuretic peptides are involved in blood pressure regulation, and large cross-sectional studies have shown lower plasma levels of N-terminal pro-natriuretic peptide levels [N-terminal atrial natriuretic peptide (N-ANP) and N-terminal brain natriuretic peptide (N-BNP)] in patients with insulin resistance, obesity, and diabetes. OBJECTIVE In this study, we prospectively tested whether plasma levels of mid-regional ANP (MR-ANP) and N-BNP predict new-onset diabetes and long-term glucose progression. DESIGN, SETTING, AND PATIENTS MR-ANP and N-BNP were measured in 1828 nondiabetic individuals of the Malmö Diet and Cancer cohort (mean age 60 yr; 61% women) who subsequently underwent a follow-up exam including an oral glucose tolerance test after a median follow-up time of 16 yr. Logistic regression was used to adjust for covariates. RESULTS During follow-up, 301 subjects developed new-onset diabetes. After full multivariate adjustment, MR-ANP was significantly inversely associated with incident diabetes (OR = 0.85; 95% CI = 0.73-0.99; P = 0.034) but not N-BNP (OR = 0.92; 95% CI = 0.80-1.06; P = 0.262). In fully adjusted linear regression models, the progression of fasting glucose during follow-up was significantly inversely related to baseline levels of MR-ANP (P = 0.004) but not N-BNP (P = 0.129). Quartile analyses revealed that the overall association was mainly accounted for by excess risk of incident diabetes in subjects belonging to the lowest quartile of MR-ANP. After full adjustment, the odds ratio for incident diabetes in the bottom compared with the top quartile of MR-ANP was 1.65 (OR = 1.08-2.51, P = 0.019) and 1.43 (OR = 1.04-1.96, P = 0.027) compared with all other subjects. CONCLUSION Low plasma levels of MR-ANP predict development of future diabetes and glucose progression over time, suggesting a causal role of ANP deficiency in diabetes development.
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Affiliation(s)
- Martin Magnusson
- Departments of Clinical Sciences, Lund University, Skåne University Hospital, Ent 35, Floor 2, SE-205 02 Malmö, Sweden.
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Roy S, Mondru AK, Dontamalla SK, Vaddepalli RP, Sannigrahi S, Veerareddy PR. Methoxy VO-salen stimulates pancreatic β cell survival by upregulation of eNOS and downregulation of apoptosis in STZ-induced diabetic rats. Biol Trace Elem Res 2011; 144:1095-111. [PMID: 21748304 DOI: 10.1007/s12011-011-9139-1] [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] [Received: 04/04/2011] [Accepted: 06/30/2011] [Indexed: 12/21/2022]
Abstract
The present study was designed to investigate the effect of MetVO-salen in ameliorating diabetes and oxidative stress in the pancreas of diabetic rats. Streptozotocin (STZ)-induced diabetic rats were treated with MetVO-salen complex intraperitonially (0.3 and 0.6 mg/kg) thrice a week and continued for 8 weeks. Total cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides in serum, and blood glucose were estimated. Furthermore, oxidative stress in rats was also investigated in terms of superoxide dismutase (SOD), catalase, lipid peroxidation, and glutathione (GSH). In addition, the anti-diabetic activity of MetVO-salen was also investigated by assessing histopathological, immunohistochemical in terms of endothelial nitric oxide synthase expression, and apoptotic events in pancreas. Treatment with MetVO-salen complex reduced the blood glucose level and significantly altered the serum biochemical parameters of diabetic rats. Treatment with above complex decreased the lipid peroxidation and the antioxidant enzymes such as SOD, CAT, and GSH to near-control levels. Histopathological, immunohistochemical, and apoptotic studies also revealed that MetVO-salen-induced amelioration of the diabetic state appears to be significant to the preservation of a functional portion of the pancreatic β cells which initially prevent STZ toxicity. This study provides new direction for the management of diabetes but needs further clinical evaluation.
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Affiliation(s)
- Souvik Roy
- Department of Pharmacology, NSHM College of Pharmaceutical Technology, 124 B.L. Saha Road, Kolkata, 700053, India.
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Armani A, Marzolla V, Rosano GMC, Fabbri A, Caprio M. Phosphodiesterase type 5 (PDE5) in the adipocyte: a novel player in fat metabolism? Trends Endocrinol Metab 2011; 22:404-11. [PMID: 21741267 DOI: 10.1016/j.tem.2011.05.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Revised: 05/18/2011] [Accepted: 05/25/2011] [Indexed: 12/19/2022]
Abstract
Phosphodiesterase type 5 (PDE5) is expressed in many tissues (e.g. heart, lung, pancreas, penis) and plays a specific role in hydrolyzing cyclic guanosine monophosphate (cGMP). In adipocytes, cGMP regulates crucial functions by activating cGMP-dependent protein kinase (PKG). Interestingly, PDE5 was recently identified in adipose tissue, although its role remains unclear. Its inhibition, however, was recently shown to affect adipose differentiation and aromatase function. This review summarizes evidence supporting a role for the PDE5-regulated cGMP/PKG system in adipose tissue and its effects on adipocyte function. A better elucidation of the role of PDE5 in the adipocyte could reveal new therapeutic strategies for fighting obesity and metabolic syndrome.
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Affiliation(s)
- Andrea Armani
- Center for Clinical and Basic Research, Scientific Institute for Research, Hospitalization and Health Care (IRCCS) San Raffaele Pisana, Rome, Italy
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Doronzo G, Viretto M, Russo I, Mattiello L, Di Martino L, Cavalot F, Anfossi G, Trovati M. Nitric oxide activates PI3-K and MAPK signalling pathways in human and rat vascular smooth muscle cells: Influence of insulin resistance and oxidative stress. Atherosclerosis 2011; 216:44-53. [DOI: 10.1016/j.atherosclerosis.2011.01.019] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 01/11/2011] [Accepted: 01/12/2011] [Indexed: 10/18/2022]
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Fernández JM, Da Silva-Grigoletto ME, Caballero-Villarraso J, Gómez-Puerto JR, Viana-Montaner BH, Tasset-Cuevas I, Túnez-Fiñana I, Pérez-Martínez P, López-Miranda J, Pérez-Jiménez F. Pre-exercise Intake of Different Carbohydrates Modifies Ischemic Reactive Hyperemia After a Session of Anaerobic, But Not After Aerobic Exercise. J Strength Cond Res 2010; 24:1623-32. [DOI: 10.1519/jsc.0b013e3181d32ffc] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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De Boo S, Kopecka J, Brusa D, Gazzano E, Matera L, Ghigo D, Bosia A, Riganti C. iNOS activity is necessary for the cytotoxic and immunogenic effects of doxorubicin in human colon cancer cells. Mol Cancer 2009; 8:108. [PMID: 19925669 PMCID: PMC2785770 DOI: 10.1186/1476-4598-8-108] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2009] [Accepted: 11/19/2009] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Doxorubicin is one of the few chemotherapeutic drugs able to exert both cytotoxic and pro-immunogenic effects against cancer cells. Following the drug administration, the intracellular protein calreticulin is translocated with an unknown mechanism onto the plasma membrane, where it triggers the phagocytosis of tumour cells by dendritic cells. Moreover doxorubicin up-regulates the inducible nitric oxide (NO) synthase (iNOS) gene in cancer cells, leading to huge amounts of NO, which in turn acts as a mediator of the drug toxicity and as a chemosensitizer agent in colon cancer. Indeed by nitrating tyrosine on the multidrug resistance related protein 3, NO decreases the doxorubicin efflux from tumour cells and enhances the drug toxicity. It is not clear if NO, beside playing a role in chemosensitivity, may also play a role in doxorubicin pro-immunogenic effects. To clarify this issue, we compared the doxorubicin-sensitive human colon cancer HT29 cells with the drug-resistant HT29-dx cells and the HT29 cells silenced for iNOS (HT29 iNOS-). RESULTS In both HT29-dx and HT29 iNOS- cells, doxorubicin did not induce NO synthesis, had a lower intracellular accumulation and a lower toxicity. Moreover the drug failed to promote the translocation of calreticulin and the phagocytosis of HT29-dx and HT29 iNOS-cells, which resulted both chemoresistant and immunoresistant. However, if NO levels were exogenously increased by sodium nitroprusside, the chemosensitivity to doxorubicin was restored in HT29 iNOS-cells. In parallel the NO donor per se was sufficient to induce the exposure of calreticulin and to increase the phagocytosis of HT29 iNOS- cells by DCs and their functional maturation, thus mimicking the pro-immunogenic effects exerted by doxorubicin in the parental drug-sensitive HT29 cells. CONCLUSION Our data suggest that chemo- and immuno-resistance to anthracyclines are associated in colon cancer cells and rely on a common mechanism, that is the inability of doxorubicin to induce iNOS. Therefore NO donors might represent a promising strategy to restore both chemosensitivity and immunosensitivity to doxorubicin in resistant cells.
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Affiliation(s)
- Sara De Boo
- Department of Genetics, Biology and Biochemistry, University of Turin, via Santena 5/bis, 10126 Turin, Italy.
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Natriuretic peptides and cardiovascular damage in the metabolic syndrome: molecular mechanisms and clinical implications. Clin Sci (Lond) 2009; 118:231-40. [PMID: 19886866 DOI: 10.1042/cs20090204] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Natriuretic peptides are endogenous antagonists of vasoconstrictor and salt- and water-retaining systems in the body's defence against blood pressure elevation and plasma volume expansion, through direct vasodilator, diuretic and natriuretic properties. In addition, natriuretic peptides may play a role in the modulation of the molecular mechanisms involved in metabolic regulation and cardiovascular remodelling. The metabolic syndrome is characterized by visceral obesity, hyperlipidaemia, vascular inflammation and hypertension, which are linked by peripheral insulin resistance. Increased visceral adiposity may contribute to the reduction in the circulating levels of natriuretic peptides. The dysregulation of neurohormonal systems, including the renin-angiotensin and the natriuretic peptide systems, may in turn contribute to the development of insulin resistance in dysmetabolic patients. In obese subjects with the metabolic syndrome, reduced levels of natriuretic peptides may be involved in the development of hypertension, vascular inflammation and cardio vascular remodelling, and this may predispose to the development of cardiovascular disease. The present review summarizes the regulation and function of the natriuretic peptide system in obese patients with the metabolic syndrome and the involvement of altered bioactive levels of natriuretic peptides in the pathophysiology of cardiovascular disease in patients with metabolic abnormalities.
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Pilgram GSK, Potikanond S, Baines RA, Fradkin LG, Noordermeer JN. The roles of the dystrophin-associated glycoprotein complex at the synapse. Mol Neurobiol 2009; 41:1-21. [PMID: 19899002 PMCID: PMC2840664 DOI: 10.1007/s12035-009-8089-5] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Accepted: 10/15/2009] [Indexed: 12/30/2022]
Abstract
Duchenne muscular dystrophy is caused by mutations in the dystrophin gene and is characterized by progressive muscle wasting. A number of Duchenne patients also present with mental retardation. The dystrophin protein is part of the highly conserved dystrophin-associated glycoprotein complex (DGC) which accumulates at the neuromuscular junction (NMJ) and at a variety of synapses in the peripheral and central nervous systems. Many years of research into the roles of the DGC in muscle have revealed its structural function in stabilizing the sarcolemma. In addition, the DGC also acts as a scaffold for various signaling pathways. Here, we discuss recent advances in understanding DGC roles in the nervous system, gained from studies in both vertebrate and invertebrate model systems. From these studies, it has become clear that the DGC is important for the maturation of neurotransmitter receptor complexes and for the regulation of neurotransmitter release at the NMJ and central synapses. Furthermore, roles for the DGC have been established in consolidation of long-term spatial and recognition memory. The challenges ahead include the integration of the behavioral and mechanistic studies and the use of this information to identify therapeutic targets.
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Affiliation(s)
- Gonneke S K Pilgram
- Department of Molecular and Cell Biology, Leiden University Medical Center, The Netherlands
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Abstract
Insulin is a vascular hormone, able to influence vascular cell responses. In this review, we consider the insulin actions on vascular endothelium and on vascular smooth muscle cells (VSMC) both in physiological conditions and in the presence of insulin resistance. In particular, we focus the relationships between activation of insulin signalling pathways of phosphatidylinositol-3 kinase (PI3-K) and mitogen-activated protein kinase (MAPK) and the different vascular actions of insulin, with a particular attention to the insulin ability to activate the pathway nitric oxide (NO)/cyclic GMP/PKG via PI3-K, owing to the peculiar relevance of NO in vascular biology. We also discuss the insulin actions mediated by the MAPK pathway (such as endothelin-1 synthesis and secretion and VSMC proliferation and migration) and by the interactions between the two pathways, both in insulin-sensitive and in insulin-resistant states. Finally, we consider the influence of free fatty acids, cytokines and endothelin on vascular insulin resistance.
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Affiliation(s)
- Giovanni Anfossi
- Internal Medicine University Unit, San Luigi Gonzaga Faculty of Medicine and Department of Clinical and Biological Sciences, Turin University, San Luigi Gonzaga Hospital, 10043 Orbassano, Turin, Italy
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Henstridge DC, Drew BG, Formosa MF, Natoli AK, Cameron-Smith D, Duffy SJ, Kingwell BA. The effect of the nitric oxide donor sodium nitroprusside on glucose uptake in human primary skeletal muscle cells. Nitric Oxide 2009; 21:126-31. [PMID: 19567271 DOI: 10.1016/j.niox.2009.06.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Revised: 06/10/2009] [Accepted: 06/24/2009] [Indexed: 11/29/2022]
Abstract
Nitric oxide (NO) has been implicated as an important signaling molecule in the insulin-independent, contraction-mediated glucose uptake pathway and may represent a novel strategy for blood glucose control in patients with type 2 diabetes (T2DM). The current study sought to determine whether the NO donor, sodium nitroprusside (SNP) increases glucose uptake in primary human skeletal muscle cells (HSkMC) derived from both healthy individuals and patients with T2DM. Vastus lateralis muscle cell cultures were derived from seven males with T2DM (aged 54 +/-2 years, BMI 31.7 +/-1.2 kg/m(2), fasting plasma glucose 9.52+/-0.80 mmol/L) and eight healthy individuals (aged 46 +/-2 years, BMI 27.1 +/- 1.5 kg/m(2), fasting plasma glucose 4.69+/-0.12 mmol/L). Cultures were treated with both therapeutic (0.2 and 2 microM) and supratherapeutic (3, 10 and 30 mM) concentrations of SNP. An additional NO donor S-nitroso-N-acetyl-d,l-penicillamine (SNAP) was also examined at a concentration of 50 microM. Glucose uptake was significantly increased following both 30 and 60 min incubations with the supratherapeutic SNP treatments (P=0.03) but not the therapeutic SNP doses (P=0.60) or SNAP (P=0.54). There was no difference in the response between the healthy and T2DM cell lines with any treatment or dose. The current study demonstrates that glucose uptake is elevated by supratherapeutic, but not therapeutic doses of SNP in human primary skeletal muscle cells derived from both healthy volunteers and patients with T2D. These data confirm that nitric oxide donors have potential therapeutic utility to increase glucose uptake in humans, but that SNP only achieves this in supratherapeutic doses. Further study to delineate mechanisms and the therapeutic window is warranted.
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Affiliation(s)
- Darren C Henstridge
- Alfred & Baker Medical Unit, Baker IDI Heart and Diabetes Institute, Melbourne 8008, Vic., Australia
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Olivares-Reyes JA, Arellano-Plancarte A, Castillo-Hernandez JR. Angiotensin II and the development of insulin resistance: implications for diabetes. Mol Cell Endocrinol 2009; 302:128-39. [PMID: 19150387 DOI: 10.1016/j.mce.2008.12.011] [Citation(s) in RCA: 141] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2008] [Revised: 12/12/2008] [Accepted: 12/13/2008] [Indexed: 12/31/2022]
Abstract
Angiotensin II (Ang II), the major effector hormone of the renin-angiotensin system (RAS), has an important role in the regulation of vascular and renal homeostasis. Clinical and pharmacological studies have recently shown that Ang II is a critical promoter of insulin resistance and diabetes mellitus type 2. Ang II exerts its actions on insulin-sensitive tissues such as liver, muscle and adipose tissue where it has effects on the insulin receptor (IR), insulin receptor substrate (IRS) proteins and the downstream effectors PI3K, Akt and GLUT4. The molecular mechanisms involved have not been completely identified, but the role of serine/threonine phosphorylation of the IR and IRS-1 proteins in desensitization of insulin action has been well established. The purpose of this review is to highlight recent advances in the understanding of Ang II actions which lead to the development of insulin resistance and its implications for diabetes.
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Affiliation(s)
- J Alberto Olivares-Reyes
- Department of Biochemistry, Center for Research and Advanced Studies of the National Polytechnic Institute, CINVESTAV-IPN, Mexico, DF, Mexico.
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Henstridge DC, Duffy SJ, Formosa MF, Ahimastos AA, Thompson BR, Kingwell BA. Oral nitrate therapy does not affect glucose metabolism in healthy men. Clin Exp Pharmacol Physiol 2009; 36:1086-92. [PMID: 19413595 DOI: 10.1111/j.1440-1681.2009.05195.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. Previously, we demonstrated that nitric oxide (NO) may be an important mediator of peripheral glucose disposal. The aim of the present study was to determine whether acute oral nitrate therapy improves glucose metabolism in healthy individuals. 2. Healthy men (n = 10), aged between 19 and 46 years, participated in a randomized cross-over placebo-controlled study. During Visit 1, participants received a dose-graded intravenous infusion of sodium nitroprusside (SNP; titrated from a dose of 0.5 microg/kg per min to a maximum of 2 microg/kg per min and delivered at a rate of 2 mL/min over 30 min). On Visits 2, 3 and 4, participants received oral extended-release isosorbide mononitrate (120 mg), pentaerythritol tetranitrate (160 mg) and placebo in a randomized Latin square design (one treatment per visit). The main outcome measures were plasma glucose and insulin levels and glucose tolerance determined by an oral glucose tolerance test following the SNP infusion and 3 h after nitrate/placebo administration. Exhaled NO, cGMP and pulmonary blood flow were also measured for 3 h after administration of nitrate/placebo and after SNP infusion. 3. None of the nitrate interventions influenced measures of glucose metabolism. Following SNP infusion, there was no change in plasma glucose (P = 0.42) or insulin (P = 0.25) levels, and the response to a glucose load did not different from baseline (P = 0.46). Similarly, neither of the oral nitrates altered plasma glucose (P = 0.24) or insulin levels (P = 0.90) or glucose tolerance (P = 0.56) compared with placebo. 4. In conclusion, these results indicate that acute oral nitrate therapy does not influence glucose metabolism. Studies using NO donors in a chronic setting are required to clarify the role of NO in mediating peripheral glucose uptake.
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Affiliation(s)
- Darren C Henstridge
- Alfred and Baker Medical Unit, Baker IDI Heart and Diabetes Institute, Melbourne, Victoria, Australia
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