BACKGROUND: C-reactive protein (CRP) is an acute inflammatory protein detected in obese patients with metabolic syndrome. Moreover, increased CRP levels have been linked with atherosclerotic disease, congestive heart failure, and ischemic heart disease, suggesting that it is not only a biomarker but also plays an active role in the pathophysiology of cardiovascular diseases. Since endothelial dysfunction plays an essential role in various cardiovascular pathologies and is characterized by increased expression of cell adhesion molecules and inflammatory markers, we aimed to detect specific markers of endothelial dysfunction, inflammation, and oxidative stress in spontaneously hypertensive rats (SHR) expressing human CRP. This model is genetically predisposed to the development of the metabolic syndrome. METHODS: Transgenic SHR male rats (SHR-CRP) and non-transgenic SHR (SHR) at the age of 8 months were used. Metabolic profile (including serum and tissue triglyceride (TAG), serum insulin concentrations, insulin-stimulated incorporation of glucose, and serum non-esterified fatty acids (NEFA) levels) was measured. In addition, human serum CRP, MCP-1 (monocyte chemoattractant protein-1), and adiponectin were evaluated by means of ELISA, histological analysis was used to study morphological changes in the aorta, and western blot analysis of aortic tissue was performed to detect expression of endothelial, inflammatory, and oxidative stress markers. RESULTS: The presence of human CRP was associated with significantly decreased insulin-stimulated glycogenesis in skeletal muscle, increased muscle and hepatic accumulation of TAG and decreased plasmatic cGMP concentrations, reduced adiponectin levels, and increased monocyte chemoattractant protein-1 (MCP-1) levels in the blood, suggesting pro-inflammatory and presence of multiple features of metabolic syndrome in SHR-CRP animals. Histological analysis of aortic sections did not reveal any visible morphological changes in animals from both SHR and SHR-CRP rats. Western blot analysis of the expression of proteins related to the proper function of endothelium demonstrated significant differences in the expression of p-eNOS/eNOS in the aorta, although endoglin (ENG) protein expression remained unaffected. In addition, the presence of human CRP in SHR in this study did not affect the expression of inflammatory markers, namely p-NFkB, P-selectin, and COX2 in the aorta. On the other hand, biomarkers related to oxidative stress, such as HO-1 and SOD3, were significantly changed, indicating the induction of oxidative stress. CONCLUSIONS: Our findings demonstrate that CRP alone cannot fully induce the expression of endothelial dysfunction biomarkers, suggesting other risk factors of cardiovascular disorders are necessary to be involved to induce endothelial dysfunction with CRP.
- MeSH
- adiponektin MeSH
- aorta MeSH
- biologické markery metabolismus MeSH
- C-reaktivní protein metabolismus MeSH
- chemokin CCL2 MeSH
- hypertenze * MeSH
- inzuliny * metabolismus MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- metabolický syndrom * diagnóza genetika MeSH
- oxidační stres MeSH
- potkani inbrední SHR MeSH
- zánět MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVE: Members of the insulin/insulin-like growth factor (IGF) superfamily are well conserved across the evolutionary tree. We recently showed that four viruses in the Iridoviridae family possess genes that encode proteins highly homologous to human insulin/IGF-1. Using chemically synthesized single-chain (sc), i.e., IGF-1-like, forms of the viral insulin/IGF-1-like peptides (VILPs), we previously showed that they can stimulate human receptors. Because these peptides possess potential cleavage sites to form double chain (dc), i.e., more insulin-like, VILPs, in this study, we have characterized dc forms of VILPs for Grouper iridovirus (GIV), Singapore grouper iridovirus (SGIV) and Lymphocystis disease virus-1 (LCDV-1) for the first time. METHODS: The dcVILPs were chemically synthesized. Using murine fibroblast cell lines overexpressing insulin receptor (IR-A or IR-B) or IGF1R, we first determined the binding affinity of dcVILPs to the receptors and characterized post-receptor signaling. Further, we used C57BL/6J mice to study the effect of dcVILPs on lowering blood glucose. We designed a 3-h dcVILP in vivo infusion experiment to determine the glucose uptake in different tissues. RESULTS: GIV and SGIV dcVILPs bind to both isoforms of human insulin receptor (IR-A and IR-B) and to the IGF1R, and for the latter, show higher affinity than human insulin. These dcVILPs stimulate IR and IGF1R phosphorylation and post-receptor signaling in vitro and in vivo. Both GIV and SGIV dcVILPs stimulate glucose uptake in mice. In vivo infusion experiments revealed that while insulin (0.015 nmol/kg/min) and GIV dcVILP (0.75 nmol/kg/min) stimulated a comparable glucose uptake in heart and skeletal muscle and brown adipose tissue, GIV dcVILP stimulated 2-fold higher glucose uptake in white adipose tissue (WAT) compared to insulin. This was associated with increased Akt phosphorylation and glucose transporter type 4 (GLUT4) gene expression compared to insulin in WAT. CONCLUSIONS: Our results show that GIV and SGIV dcVILPs are active members of the insulin superfamily with unique characteristics. Elucidating the mechanism of tissue specificity for GIV dcVILP will help us to better understand insulin action, design new analogs that specifically target the tissues and provide new insights into their potential role in disease.
- MeSH
- bílá tuková tkáň metabolismus MeSH
- buněčné linie MeSH
- CD antigeny MeSH
- fosforylace MeSH
- glukosa metabolismus MeSH
- hnědá tuková tkáň metabolismus MeSH
- insulinu podobný růstový faktor I metabolismus MeSH
- inzulin genetika metabolismus MeSH
- inzuliny metabolismus MeSH
- Iridovirus genetika MeSH
- iridoviry genetika MeSH
- lidé MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- receptor IGF typ 1 genetika metabolismus MeSH
- receptor inzulinu metabolismus MeSH
- signální transdukce MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Klíčová slova
- semaglutid,
- MeSH
- diabetes mellitus * farmakoterapie MeSH
- glukagonu podobné peptidy aplikace a dávkování terapeutické užití MeSH
- glukagonu podobný peptid 1 terapeutické užití MeSH
- hypoglykemie komplikace MeSH
- hypoglykemika terapeutické užití MeSH
- inzuliny farmakokinetika metabolismus terapeutické užití MeSH
- kardiovaskulární nemoci prevence a kontrola MeSH
- klinické zkoušky jako téma MeSH
- kongresy jako téma MeSH
- krevní glukóza analýza účinky léků MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- novinové články MeSH
Numerous epidemiological and experimental studies have demonstrated that patients who suffer from metabolic disorders, such as type 2 diabetes mellitus (T2DM) or obesity, have higher risks of cognitive dysfunction and of Alzheimer's disease (AD). Impaired insulin signaling in the brain could contribute to the formation of neurofibrillary tangles, which contain an abnormally hyperphosphorylated tau protein. This study aimed to determine whether potential tau hyperphosphorylation could be detected in an obesity-induced pre-diabetes state and whether anorexigenic agents could affect this state. We demonstrated that 6-month-old mice with monosodium glutamate (MSG) obesity, which represent a model of obesity-induced pre-diabetes, had increased tau phosphorylation at Ser396 and Thr231 in the hippocampus compared with the controls, as determined by western blots. Two weeks of subcutaneous treatment with a lipidized analog of prolactin-releasing peptide (palm-PrRP31) or with the T2DM drug liraglutide, which both had a central anorexigenic effect, resulted in increased phosphorylation of the insulin cascade kinases PDK1 (Ser241), Akt (Thr308), and GSK-3β (Ser9). Furthermore, these drugs attenuated phosphorylation at Ser396, Thr231, and Thr212 of tau and of the primary tau kinases in the hippocampi of 6-month-old MSG-obese mice. We identified tau hyperphosphorylation in the obesity-induced pre-diabetes state in MSG-obese mice and demonstrated the beneficial effects of palm-PrRP31 and liraglutide, both of known central anorexigenic effects, on hippocampal insulin signaling and on tau phosphorylation.
- MeSH
- analýza rozptylu MeSH
- časové faktory MeSH
- chuťové esence toxicita MeSH
- fosforylace účinky léků MeSH
- glukagonu podobný peptid 1 genetika farmakologie MeSH
- glukózový toleranční test MeSH
- glutamát sodný toxicita MeSH
- hipokampus účinky léků metabolismus MeSH
- hormon uvolňující prolaktin účinky léků farmakologie MeSH
- inzuliny metabolismus MeSH
- lipopeptidy metabolismus terapeutické užití MeSH
- modely nemocí na zvířatech MeSH
- myši MeSH
- obezita * chemicky indukované farmakoterapie patologie MeSH
- proteiny tau metabolismus MeSH
- receptory spřažené s G-proteiny metabolismus MeSH
- signální transdukce účinky léků MeSH
- tělesná hmotnost účinky léků MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- MeSH
- diabetes mellitus * dějiny farmakoterapie MeSH
- glukagonu podobný peptid 1 * účinky léků MeSH
- inzulin farmakologie metabolismus terapeutické užití MeSH
- inzuliny * dějiny farmakologie metabolismus terapeutické užití MeSH
- kombinovaná terapie metody MeSH
- kongresy jako téma MeSH
- lidé MeSH
- receptory glukagonu * agonisté MeSH
- Check Tag
- lidé MeSH
- MeSH
- adherence k farmakoterapii MeSH
- diabetes mellitus 2. typu * farmakoterapie MeSH
- glukagonu podobný peptid 1 * analogy a deriváty terapeutické užití MeSH
- hmotnostní úbytek účinky léků MeSH
- individualizovaná medicína MeSH
- inzuliny metabolismus terapeutické užití MeSH
- kombinovaná farmakoterapie metody MeSH
- krevní glukóza metabolismus účinky léků MeSH
- lidé MeSH
- postprandiální období účinky léků MeSH
- receptory glukagonu agonisté účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- kongresy MeSH
- novinové články MeSH
- MeSH
- diabetes mellitus 2. typu * farmakoterapie MeSH
- distribuce tělesného tuku škodlivé účinky MeSH
- inzuliny farmakologie metabolismus škodlivé účinky terapeutické užití MeSH
- lidé MeSH
- makrofágy sekrece účinky léků MeSH
- poměr pasu a boků škodlivé účinky MeSH
- tuková tkáň cytologie účinky léků MeSH
- zánět imunologie MeSH
- Check Tag
- lidé MeSH
Premixované inzuliny jsou přípravky obsahující krátkodobě a dlouhodobě účinný inzulin v definovaném poměru. Jsou určeny zejména pro terapii pacientů s diabetem 2. typu. Charakteristická farmakodynamika nabízí dobré ovlivnění zejména postprandiální glykemie. Premixovaná analoga vykazují ve srovnání s humánními premixovanými inzuliny větší potenciál snížení postprandiální glykemie a nižší riziko hypoglykemie. K dispozici je výběr přípravků s 25 %, 30 % a 50 % krátkodobě účinné složky, což umožňuje individuální nastavení terapie. Po selhání terapie kombinací perorálních antidiabetik jsou premixované inzuliny jedním z možných inzulinových režimů volby.
Premixed insulins are preparations containing the short- and long-acting insulin in a defined ratio. They are designed primarily for the treatment of patients with type 2 diabetes. Their distinctive pharmacodynamics represent an advantage, especially for the control of postprandial glycaemia. Compared to human insulin, premixed analogues have greater potential to reduce postprandial glycaemia and lower the risk of hypogiycaemia. There is a variety of preparations containing 25%, 30% and 50% of short-acting ingredients, which allows the individual setting of therapy. After failure of combination therapy with oral hypoglycaemic agents, premixed insulins represent one of the possible regimens of choice.
- MeSH
- diabetes mellitus 1. typu * diagnóza farmakoterapie patofyziologie MeSH
- diabetes mellitus 2. typu * diagnóza farmakoterapie patofyziologie MeSH
- dlouhodobě působící inzulin farmakologie terapeutické užití MeSH
- hypoglykemika terapeutické užití MeSH
- inzulin krev sekrece MeSH
- inzuliny * farmakologie metabolismus terapeutické užití MeSH
- kombinovaná farmakoterapie metody MeSH
- komplikace diabetu epidemiologie MeSH
- krátkodobě působící inzuliny farmakologie terapeutické užití MeSH
- krevní glukóza analýza metabolismus účinky léků MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
- MeSH
- diabetes mellitus 2. typu * farmakoterapie MeSH
- glykovaný hemoglobin normy účinky léků MeSH
- inzuliny aplikace a dávkování metabolismus škodlivé účinky MeSH
- komplikace diabetu epidemiologie prevence a kontrola MeSH
- krevní glukóza analýza účinky léků MeSH
- lidé MeSH
- selfmonitoring glykemie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH