Nejvíce citovaný článek - PubMed ID 30810318
Metabolomic Study of Obesity and Its Treatment with Palmitoylated Prolactin-Releasing Peptide Analog in Spontaneously Hypertensive and Normotensive Rats
Since 1975, the incidence of obesity has increased to epidemic proportions, and the number of patients with obesity has quadrupled. Obesity is a major risk factor for developing other serious diseases, such as type 2 diabetes mellitus, hypertension, and cardiovascular diseases. Recent epidemiologic studies have defined obesity as a risk factor for the development of neurodegenerative diseases, such as Alzheimer's disease (AD) and other types of dementia. Despite all these serious comorbidities associated with obesity, there is still a lack of effective antiobesity treatment. Promising candidates for the treatment of obesity are anorexigenic neuropeptides, which are peptides produced by neurons in brain areas implicated in food intake regulation, such as the hypothalamus or the brainstem. These peptides efficiently reduce food intake and body weight. Moreover, because of the proven interconnection between obesity and the risk of developing AD, the potential neuroprotective effects of these two agents in animal models of neurodegeneration have been examined. The objective of this review was to explore anorexigenic neuropeptides produced and acting within the brain, emphasizing their potential not only for the treatment of obesity but also for the treatment of neurodegenerative disorders.
- Klíčová slova
- Alzheimer´s-like pathology, anorexigenic neuropeptides, antiobesity treatment, neuroprotection,
- MeSH
- Alzheimerova nemoc farmakoterapie metabolismus patologie prevence a kontrola MeSH
- hypothalamus účinky léků metabolismus patologie MeSH
- látky proti obezitě * farmakologie terapeutické užití MeSH
- lidé MeSH
- mozek účinky léků metabolismus patologie MeSH
- neurodegenerativní nemoci farmakoterapie metabolismus prevence a kontrola MeSH
- neuropeptidy * metabolismus farmakologie terapeutické užití MeSH
- neuroprotektivní látky * farmakologie terapeutické užití MeSH
- obezita * farmakoterapie metabolismus MeSH
- přijímání potravy účinky léků MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- látky proti obezitě * MeSH
- neuropeptidy * MeSH
- neuroprotektivní látky * MeSH
Alzheimer's disease (AD) is a progressive brain disorder characterized by extracellular amyloid-β (Aβ) plaques, intracellular neurofibrillary tangles formed by hyperphosphorylated Tau protein and neuroinflammation. Previous research has shown that obesity and type 2 diabetes mellitus, underlined by insulin resistance (IR), are risk factors for neurodegenerative disorders. In this study, obesity-induced peripheral and central IR and inflammation were studied in relation to AD-like pathology in the brains and periphery of APP/PS1 mice, a model of Aβ pathology, fed a high-fat diet (HFD). APP/PS1 mice and their wild-type controls fed either a standard diet or HFD were characterized at the ages of 3, 6 and 10 months by metabolic parameters related to obesity via mass spectroscopy, nuclear magnetic resonance, immunoblotting and immunohistochemistry to quantify how obesity affected AD pathology. The HFD induced substantial peripheral IR leading to central IR. APP/PS1-fed HFD mice had more pronounced IR, glucose intolerance and liver steatosis than their WT controls. The HFD worsened Aβ pathology in the hippocampi of APP/PS1 mice and significantly supported both peripheral and central inflammation. This study reveals a deleterious effect of obesity-related mild peripheral inflammation and prediabetes on the development of Aβ and Tau pathology and neuroinflammation in APP/PS1 mice.
- Klíčová slova
- APP/PS1, Alzheimer’s disease, amyloid-β, glucose intolerance, inflammation, insulin resistance, neuroinflammation, obesity, tau protein,
- MeSH
- Alzheimerova nemoc * etiologie MeSH
- amyloidní beta-protein MeSH
- diabetes mellitus 2. typu * MeSH
- dieta s vysokým obsahem tuků škodlivé účinky MeSH
- inzulinová rezistence * MeSH
- myši MeSH
- neurozánětlivé nemoci MeSH
- zánět MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- amyloidní beta-protein MeSH
Zucker fatty (fa/fa) rats represent a well-established and widely used model of genetic obesity. Because previous metabolomic studies have only been published for young fa/fa rats up to 20 weeks of age, which can be considered early maturity in male fa/fa rats, the aim of our work was to extend the metabolomic characterization to significantly older animals. Therefore, the urinary profiles of obese fa/fa rats and their lean controls were monitored using untargeted NMR metabolomics between 12 and 40 weeks of age. At the end of the experiment, the rats were also characterized by NMR and LC-MS serum analysis, which was supplemented by a targeted LC-MS analysis of serum bile acids and neurotransmitters. The urine analysis showed that most of the characteristic differences detected in young obese fa/fa rats persisted throughout the experiment, primarily through a decrease in microbial co-metabolite levels, the upregulation of the citrate cycle, and changes in nicotinamide metabolism compared with the age-related controls. The serum of 40-week-old obese rats showed a reduction in several bile acid conjugates and an increase in serotonin. Our study demonstrated that the fa/fa model of genetic obesity is stable up to 40 weeks of age and is therefore suitable for long-term experiments.
- Klíčová slova
- LC-MS, NMR, fa/fa rats, genetic obesity, metabolomics,
- Publikační typ
- časopisecké články MeSH
Prolactin-releasing peptide (PrRP) is an anorexigenic neuropeptide that has potential for the treatment of obesity and its complications. Recently, we designed a palmitoylated PrRP31 analog (palm11-PrRP31) that is more stable than the natural peptide and able to act centrally after peripheral administration. This analog acted as an anti-obesity and glucose-lowering agent, attenuating lipogenesis in rats and mice with high-fat (HF) diet-induced obesity. In Wistar Kyoto (WKY) rats fed a HF diet for 52 weeks, we explored glucose intolerance, but also prediabetes, liver steatosis and insulin resistance-related changes, as well as neuroinflammation in the brain. A potential beneficial effect of 6 weeks of treatment with palm11-PrRP31 and liraglutide as comparator was investigated. Liver lipid profiles, as well as urinary and plasma metabolomic profiles, were measured by lipidomics and metabolomics, respectively. Old obese WKY rats showed robust glucose intolerance that was attenuated by palm11-PrRP31, but not by liraglutide treatment. On the contrary, liraglutide had a beneficial effect on insulin resistance parameters. Despite obesity and prediabetes, WKY rats did not develop steatosis owing to HF diet feeding, even though liver lipogenesis was enhanced. Plasma triglycerides and cholesterol were not increased by HFD feeding, which points to unincreased lipid transport from the liver. The liver lipid profile was significantly altered by a HF diet that remained unaffected by palm11-PrRP31 or liraglutide treatment. The HF-diet-fed WKY rats revealed astrogliosis in the brain cortex and hippocampus, which was attenuated by treatment. In conclusion, this study suggested multiple beneficial anti-obesity-related effects of palm11-PrRP31 and liraglutide in both the periphery and brain.
- Klíčová slova
- Wistar Kyoto rats, astrocytosis, diet-induced obesity, glucose intolerance, lipid metabolism, lipidomics, liraglutide, metabolomics, prolactin-releasing peptide,
- MeSH
- dieta s vysokým obsahem tuků škodlivé účinky MeSH
- hormon uvolňující prolaktin farmakologie MeSH
- hypoglykemika farmakologie terapeutické užití MeSH
- inzulinová rezistence * MeSH
- krysa rodu Rattus MeSH
- lipidy MeSH
- liraglutid farmakologie terapeutické užití MeSH
- myši MeSH
- obezita farmakoterapie MeSH
- porucha glukózové tolerance * farmakoterapie MeSH
- potkani inbrední WKY MeSH
- prediabetes * farmakoterapie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- hormon uvolňující prolaktin MeSH
- hypoglykemika MeSH
- lipidy MeSH
- liraglutid MeSH
BACKGROUND/OBJECTIVE: Anorexigenic palmitoylated prolactin-releasing peptide (palm11-PrRP) is able to act centrally after peripheral administration in rat and mouse models of obesity, type 2 diabetes mellitus and/or neurodegeneration. Functional leptin and intact leptin signaling pathways are necessary for the body weight reducing and glucose tolerance improving effect of palm11-PrRP. We have previously shown that palm11-PrRP31 had glucose-lowering properties but not anti-obesity effect in Koletsky rats with leptin signaling disturbances, so improvements in glucose metabolism appear to be completely independent of leptin signaling. The purpose of this study was to describe relationship between metabolic and neurodegenerative pathologies and explore if palm11-PrRP31 could ameliorate them in obese fa/fa rat model with leptin signaling disruption. SUBJECT/METHODS: The fa/fa rats and their age-matched lean controls at the age 32 weeks were used for this study. The rats were infused for 2 months with saline or palm11-PrRP31 (n = 7-8 per group) at a dose of 5 mg/kg per day using Alzet osmotic pumps. During the dosing period food intake and body weight were monitored. At the end of experiment the oral glucose tolerance test was performed; plasma and tissue samples were collected and arterial blood pressure was measured. Then, markers of leptin and insulin signaling, Tau phosphorylation, neuroinflammation, and synaptogenesis were measured by western blotting and immunohistochemistry. RESULTS: Fa/fa rats developed obesity, mild glucose intolerance, and peripheral insulin resistance but not hypertension while palm11-PrRP31 treatment neither lowered body weight nor attenuated glucose tolerance but ameliorated leptin and insulin signaling and synaptogenesis in hippocampus. CONCLUSION: We demonstrated that palm11-PrRP31 had neuroprotective features without anti-obesity and glucose lowering effects in fa/fa rats. This data suggest that this analog has the potential to exert neuroprotective effect despite of leptin signaling disturbances in this rat model.
- MeSH
- diabetes mellitus 2. typu * farmakoterapie MeSH
- glukosa MeSH
- hormon uvolňující prolaktin farmakologie terapeutické užití MeSH
- inzulin terapeutické užití MeSH
- krysa rodu Rattus MeSH
- leptin * MeSH
- myši MeSH
- obezita metabolismus MeSH
- tělesná hmotnost MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- glukosa MeSH
- hormon uvolňující prolaktin MeSH
- inzulin MeSH
- leptin * MeSH
Obesity and type 2 diabetes mellitus (T2DM) are preconditions for the development of metabolic syndrome, which is reaching pandemic levels worldwide, but there are still only a few anti-obesity drugs available. One of the promising tools for the treatment of obesity and related metabolic complications is anorexigenic peptides, such as prolactin-releasing peptide (PrRP). PrRP is a centrally acting neuropeptide involved in food intake and body weight (BW) regulation. In its natural form, it has limitations for peripheral administration; thus, we designed analogs of PrRP lipidized at the N-terminal region that showed high binding affinities, increased stability and central anorexigenic effects after peripheral administration. In this review, we summarize the preclinical results of our chronic studies on the pharmacological role of the two most potent palmitoylated PrRP31 analogs in various mouse and rat models of obesity, glucose intolerance, and insulin resistance. We used mice and rats with diet-induced obesity fed a high-fat diet, which is considered to simulate the most common form of human obesity, or rodent models with leptin deficiency or disrupted leptin signaling in which long-term food intake regulation by leptin is distorted. The rodent models described in this review are models of metabolic syndrome with different severities, such as obesity or morbid obesity, prediabetes or diabetes and hypertension. We found that the effects of palmitoylated PrRP31 on food intake and BW but not on glucose intolerance require intact leptin signaling. Thus, palmitoylated PrRP31 analogs have potential as therapeutics for obesity and related metabolic complications.
- Klíčová slova
- leptin resistance, obesity, prolactin-releasing peptide, rodent models, type 2 diabetes,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Prolactin-releasing peptide (PrRP) belongs to the large RF-amide neuropeptide family with a conserved Arg-Phe-amide motif at the C-terminus. PrRP plays a main role in the regulation of food intake and energy expenditure. This review focuses not only on the physiological functions of PrRP, but also on its pharmacological properties and the actions of its G-protein coupled receptor, GPR10. Special attention is paid to structure-activity relationship studies on PrRP and its analogs as well as to their effect on different physiological functions, mainly their anorexigenic and neuroprotective features and the regulation of the cardiovascular system, pain, and stress. Additionally, the therapeutic potential of this peptide and its analogs is explored.
- Klíčová slova
- GPR10, RF-amide peptides, energy expenditure, food intake regulation, neuroprotection, prolactin-releasing peptide, signaling,
- MeSH
- energetický metabolismus účinky léků MeSH
- hormon uvolňující prolaktin chemie metabolismus farmakologie MeSH
- lidé MeSH
- neurodegenerativní nemoci farmakoterapie patologie MeSH
- neuroprotektivní látky chemie farmakologie terapeutické užití MeSH
- přijímání potravy účinky léků MeSH
- receptory spřažené s G-proteiny chemie genetika metabolismus MeSH
- signální transdukce účinky léků MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- hormon uvolňující prolaktin MeSH
- neuroprotektivní látky MeSH
- PRLHR protein, human MeSH Prohlížeč
- receptory spřažené s G-proteiny MeSH