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1.
Cell ; 181(6): 1246-1262.e22, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-32442405

RESUMEN

There is considerable inter-individual variability in susceptibility to weight gain despite an equally obesogenic environment in large parts of the world. Whereas many studies have focused on identifying the genetic susceptibility to obesity, we performed a GWAS on metabolically healthy thin individuals (lowest 6th percentile of the population-wide BMI spectrum) in a uniquely phenotyped Estonian cohort. We discovered anaplastic lymphoma kinase (ALK) as a candidate thinness gene. In Drosophila, RNAi mediated knockdown of Alk led to decreased triglyceride levels. In mice, genetic deletion of Alk resulted in thin animals with marked resistance to diet- and leptin-mutation-induced obesity. Mechanistically, we found that ALK expression in hypothalamic neurons controls energy expenditure via sympathetic control of adipose tissue lipolysis. Our genetic and mechanistic experiments identify ALK as a thinness gene, which is involved in the resistance to weight gain.


Asunto(s)
Quinasa de Linfoma Anaplásico/genética , Delgadez/genética , Tejido Adiposo/metabolismo , Adulto , Animales , Línea Celular , Estudios de Cohortes , Drosophila/genética , Estonia , Femenino , Humanos , Leptina/genética , Lipólisis/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/genética , Interferencia de ARN/fisiología , Adulto Joven
2.
Cell ; 159(6): 1404-16, 2014 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25480301

RESUMEN

Obesity is associated with increased blood pressure (BP), which in turn increases the risk of cardiovascular diseases. We found that the increase in leptin levels seen in diet-induced obesity (DIO) drives an increase in BP in rodents, an effect that was not seen in animals deficient in leptin or leptin receptors (LepR). Furthermore, humans with loss-of-function mutations in leptin and the LepR have low BP despite severe obesity. Leptin's effects on BP are mediated by neuronal circuits in the dorsomedial hypothalamus (DMH), as blocking leptin with a specific antibody, antagonist, or inhibition of the activity of LepR-expressing neurons in the DMH caused a rapid reduction of BP in DIO mice, independent of changes in weight. Re-expression of LepRs in the DMH of DIO LepR-deficient mice caused an increase in BP. These studies demonstrate that leptin couples changes in weight to changes in BP in mammalian species.


Asunto(s)
Hipertensión/metabolismo , Leptina/metabolismo , Obesidad/metabolismo , Animales , Leptina/genética , Ratones Endogámicos C57BL , Mutación , Neuronas/metabolismo , Obesidad/patología , Receptores de Leptina/genética , Receptores de Leptina/metabolismo , Transducción de Señal
3.
Proc Natl Acad Sci U S A ; 121(1): e2310685120, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38147550

RESUMEN

Leptin protein was thought to be unique to leptin receptor (LepR), but the phenotypes of mice with mutation in LepR [db/db (diabetes)] and leptin [ob/ob (obese)] are not identical, and the cause remains unclear. Here, we show that db/db, but not ob/ob, mice had defect in tenotomy-induced heterotopic ossification (HO), implicating alternative ligand(s) for LepR might be involved. Ligand screening revealed that ANGPTL4 (angiopoietin-like protein 4), a stress and fasting-induced factor, was elicited from brown adipose tissue after tenotomy, bound to LepR on PRRX1+ mesenchymal cells at the HO site, thus promotes chondrogenesis and HO development. Disruption of LepR in PRRX1+ cells, or lineage ablation of LepR+ cells, or deletion of ANGPTL4 impeded chondrogenesis and HO in mice. Together, these findings identify ANGPTL4 as a ligand for LepR to regulate the formation of acquired HO.


Asunto(s)
Leptina , Osificación Heterotópica , Animales , Ratones , Leptina/genética , Ligandos , Ratones Endogámicos C57BL , Osteogénesis , Receptores de Leptina/genética , Receptores de Leptina/metabolismo
4.
N Engl J Med ; 388(24): 2253-2261, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37314706

RESUMEN

Hormone absence or inactivity is common in congenital disease, but hormone antagonism remains controversial. Here, we characterize two novel homozygous leptin variants that yielded antagonistic proteins in two unrelated children with intense hyperphagia, severe obesity, and high circulating levels of leptin. Both variants bind to the leptin receptor but trigger marginal, if any, signaling. In the presence of nonvariant leptin, the variants act as competitive antagonists. Thus, treatment with recombinant leptin was initiated at high doses, which were gradually lowered. Both patients eventually attained near-normal weight. Antidrug antibodies developed in the patients, although they had no apparent effect on efficacy. No severe adverse events were observed. (Funded by the German Research Foundation and others.).


Asunto(s)
Leptina , Obesidad Mórbida , Niño , Humanos , Anticuerpos , Homocigoto , Leptina/genética , Obesidad Mórbida/genética , Transducción de Señal
5.
Proc Natl Acad Sci U S A ; 120(22): e2300155120, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37216518

RESUMEN

Obesity has been recognized as one of the most significant risk factors for the deterioration and mortality associated with COVID-19, but the significance of obesity itself differs among ethnicity. Multifactored analysis of our single institute-based retrospective cohort revealed that high visceral adipose tissue (VAT) burden, but not other obesity-associated markers, was related to accelerated inflammatory responses and the mortality of Japanese COVID-19 patients. To elucidate the mechanisms how VAT-dominant obesity induces severe inflammation after severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, we infected two different strains of obese mice, C57BL/6JHamSlc-ob/ob (ob/ob), C57BLKS/J-db/db (db/db), genetically impaired in the leptin ligand and receptor, respectively, and control C57BL/6 mice with mouse-adapted SARS-CoV-2. Here, we revealed that VAT-dominant ob/ob mice were extremely more vulnerable to SARS-CoV-2 due to excessive inflammatory responses when compared to SAT-dominant db/db mice. In fact, SARS-CoV-2 genome and proteins were more abundant in the lungs of ob/ob mice, engulfed in macrophages, resulting in increased cytokine production including interleukin (IL)-6. Both an anti-IL-6 receptor antibody treatment and the prevention of obesity by leptin replenishment improved the survival of SARS-CoV-2-infected ob/ob mice by reducing the viral protein burden and excessive immune responses. Our results have proposed unique insights and clues on how obesity increases the risk of cytokine storm and death in patients with COVID-19. Moreover, earlier administration of antiinflammatory therapeutics including anti-IL-6R antibody to VAT-dominant patients might improve clinical outcome and stratification of the treatment for COVID-19, at least in Japanese patients.


Asunto(s)
COVID-19 , Malus , Ratones , Animales , Leptina/genética , Citocinas , COVID-19/complicaciones , Estudios Retrospectivos , SARS-CoV-2 , Ratones Endogámicos C57BL , Obesidad/complicaciones , Obesidad/genética , Interleucina-6 , Ratones Obesos
6.
J Biol Chem ; 300(8): 107562, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39002670

RESUMEN

The hormone leptin, primarily secreted by adipocytes, plays a crucial role in regulating whole-body energy homeostasis. Homozygous loss-of-function mutations in the leptin gene (LEP) cause hyperphagia and severe obesity, primarily through alterations in leptin's affinity for its receptor or changes in serum leptin concentrations. Although serum concentrations are influenced by various factors (e.g., gene expression, protein synthesis, stability in the serum), proper delivery of leptin from its site of synthesis in the endoplasmic reticulum via the secretory pathway to the extracellular serum is a critical step. However, the regulatory mechanisms and specific machinery involved in this trafficking route, particularly in the context of human LEP mutations, remain largely unexplored. We have employed the Retention Using Selective Hooks system to elucidate the secretory pathway of leptin. We have refined this system into a medium-throughput assay for examining the pathophysiology of a range of obesity-associated LEP variants. Our results reveal that leptin follows the default secretory pathway, with no additional regulatory steps identified prior to secretion. Through screening of leptin variants, we identified three mutations that lead to proteasomal degradation of leptin and one variant that significantly decreased leptin secretion, likely through aberrant disulfide bond formation. These observations have identified novel pathogenic effects of leptin variants, which can be informative for therapeutics and diagnostics. Finally, our novel quantitative screening platform can be adapted for other secreted proteins.


Asunto(s)
Leptina , Humanos , Leptina/metabolismo , Leptina/genética , Obesidad/metabolismo , Obesidad/genética , Vías Secretoras , Células HEK293 , Receptores de Leptina/metabolismo , Receptores de Leptina/genética , Mutación , Complejo de la Endopetidasa Proteasomal/metabolismo , Complejo de la Endopetidasa Proteasomal/genética
7.
Hum Mol Genet ; 32(13): 2241-2250, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37027192

RESUMEN

OBJECTIVE: In Friedreich's ataxia (FRDA), the most affected tissues are not accessible to sampling and available transcriptomic findings originate from blood-derived cells and animal models. Herein, we aimed at dissecting for the first time the pathophysiology of FRDA by means of RNA-sequencing in an affected tissue sampled in vivo. METHODS: Skeletal muscle biopsies were collected from seven FRDA patients before and after treatment with recombinant human Erythropoietin (rhuEPO) within a clinical trial. Total RNA extraction, 3'-mRNA library preparation and sequencing were performed according to standard procedures. We tested for differential gene expression with DESeq2 and performed gene set enrichment analysis with respect to control subjects. RESULTS: FRDA transcriptomes showed 1873 genes differentially expressed from controls. Two main signatures emerged: (1) a global downregulation of the mitochondrial transcriptome as well as of ribosome/translational machinery and (2) an upregulation of genes related to transcription and chromatin regulation, especially of repressor terms. Downregulation of the mitochondrial transcriptome was more profound than previously shown in other cellular systems. Furthermore, we observed in FRDA patients a marked upregulation of leptin, the master regulator of energy homeostasis. RhuEPO treatment further enhanced leptin expression. INTERPRETATION: Our findings reflect a double hit in the pathophysiology of FRDA: a transcriptional/translational issue and a profound mitochondrial failure downstream. Leptin upregulation in the skeletal muscle in FRDA may represent a compensatory mechanism of mitochondrial dysfunction, which is amenable to pharmacological boosting. Skeletal muscle transcriptomics is a valuable biomarker to monitor therapeutic interventions in FRDA.


Asunto(s)
Eritropoyetina , Ataxia de Friedreich , Animales , Humanos , Transcriptoma/genética , Leptina/genética , Ataxia de Friedreich/patología , Eritropoyetina/genética , ARN , Músculo Esquelético/metabolismo , Proteínas de Unión a Hierro/genética , Proteínas de Unión a Hierro/metabolismo
8.
Hum Genomics ; 18(1): 56, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38831447

RESUMEN

BACKGROUND: Several lines of evidence suggest that leukocyte telomere length (LTL) can affect the development of prostate cancer (PC). METHODS: Here, we employed single nucleoside polymorphisms (SNPs) as instrumental variables (IVs) for LTL (n = 472,174) and conducted Mendelian randomization analysis to estimate their causal impact on PCs (79,148 patients/61,106 controls and 6311 patients/88,902 controls). RESULTS: Every 1-s.d extension of LTL increased the risk of PCs by 34%. Additionally, the analysis of candidate mediators between LTL and PCs via two-step Mendelian randomization revealed that among the 23 candidates, Alzheimer's disease, liver iron content, sex hormone binding global levels, naive CD4-CD8-T cell% T cell, and circulating leptin levels played substantial mediating roles. There is no robust evidence to support the reverse causal relationship between LTL and the selected mediators of PCs. Adjusting for the former four mediators, rather than adjusting for circulating leptin levels, decreased the impact of LTL on PCs. CONCLUSION: This study provides potential intervention measures for preventing LTL-induced PCs.


Asunto(s)
Leucocitos , Análisis de la Aleatorización Mendeliana , Polimorfismo de Nucleótido Simple , Neoplasias de la Próstata , Telómero , Población Blanca , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Leucocitos/metabolismo , Polimorfismo de Nucleótido Simple/genética , Población Blanca/genética , Telómero/genética , Homeostasis del Telómero/genética , Leptina/genética , Leptina/sangre , Predisposición Genética a la Enfermedad , Anciano , Persona de Mediana Edad
9.
FASEB J ; 38(14): e23836, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39044640

RESUMEN

Leptin can indirectly regulate fatty-acid metabolism and synthesis in muscle in vivo and directly in incubated muscle ex vivo. In addition, non-synonymous mutations in the bovine leptin gene (LEP) are associated with carcass intramuscular fat (IMF) content. However, the effects of LEP on lipid synthesis of adipocytes have not been clearly studied at the cellular level. Therefore, this study focused on bovine primary intramuscular preadipocytes to investigate the effects of LEP on the proliferation and differentiation of intramuscular preadipocytes, as well as its regulatory mechanism in lipid synthesis. The results showed that both the LEP and leptin receptor gene (LEPR) were highly expressed in IMF tissues, and their mRNA expression levels were positively correlated at different developmental stages of intramuscular preadipocytes. The overexpression of LEP inhibited the proliferation and differentiation of intramuscular preadipocytes, while interference with LEP had the opposite effect. Additionally, LEP significantly promoted the phosphorylation level of AMPKα by promoting the protein expression of CAMKK2. Meanwhile, rescue experiments showed that the increasing effect of AMPK inhibitors on the number of intramuscular preadipocytes was significantly weakened by the overexpression of LEP. Furthermore, the overexpression of LEP could weaken the promoting effect of AMPK inhibitor on triglyceride content and droplet accumulation, and prevent the upregulation of adipogenic protein expression (SREBF1, FABP4, FASN, and ACCα) caused by AMPK inhibitor. Taken together, LEP acted on the AMPK signaling pathway by regulating the protein expression of CAMKK2, thereby downregulating the expression of proliferation-related and adipogenic-related genes and proteins, ultimately reducing intramuscular adipogenesis.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Adipocitos , Adipogénesis , Leptina , Transducción de Señal , Animales , Adipogénesis/fisiología , Bovinos , Adipocitos/metabolismo , Adipocitos/citología , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Leptina/metabolismo , Leptina/genética , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Receptores de Leptina/metabolismo , Receptores de Leptina/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/citología
10.
Cell ; 143(1): 9-12, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20887884

RESUMEN

This year, the Albert Lasker Basic Medical Research Award will be shared by Douglas Coleman and Jeffrey Friedman for their discovery of leptin, a hormone that regulates appetite and body weight. By uncovering a critical physiologic system, their discovery markedly accelerated our capacity to apply molecular and genetic techniques to understand obesity.


Asunto(s)
Distinciones y Premios , Leptina/genética , Leptina/metabolismo , Fisiología/historia , Apetito , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Obesidad/fisiopatología , Estados Unidos
11.
Biochem J ; 481(5): 345-362, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38314646

RESUMEN

Adipogenesis, defined as the development of mature adipocytes from stem cell precursors, is vital for the expansion, turnover and health of adipose tissue. Loss of adipogenic potential in adipose stem cells, or impairment of adipogenesis is now recognised as an underlying cause of adipose tissue dysfunction and is associated with metabolic disease. In this study, we sought to determine the role of AMP-activated protein kinase (AMPK), an evolutionarily conserved master regulator of energy homeostasis, in adipogenesis. Primary murine adipose-derived stem cells were treated with a small molecule AMPK activator (BI-9774) during key phases of adipogenesis, to determine the effect of AMPK activation on adipocyte commitment, maturation and function. To determine the contribution of the repression of lipogenesis by AMPK in these processes, we compared the effect of pharmacological inhibition of acetyl-CoA carboxylase (ACC). We show that AMPK activation inhibits adipogenesis in a time- and concentration-dependent manner. Transient AMPK activation during adipogenic commitment leads to a significant, ACC-independent, repression of adipogenic transcription factor expression. Furthermore, we identify a striking, previously unexplored inhibition of leptin gene expression in response to both short-term and chronic AMPK activation irrespective of adipogenesis. These findings reveal that in addition to its effect on adipogenesis, AMPK activation switches off leptin gene expression in primary mouse adipocytes independently of adipogenesis. Our results identify leptin expression as a novel target of AMPK through mechanisms yet to be identified.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Adipogénesis , Animales , Ratones , Células 3T3-L1 , Adipocitos/metabolismo , Adipogénesis/genética , Tejido Adiposo/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Leptina/genética , Leptina/farmacología , Leptina/metabolismo
12.
Proc Natl Acad Sci U S A ; 119(10): e2200083119, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35238641

RESUMEN

SignificanceWhile increasing evidence associates the disruption of circadian rhythms with pathologic conditions, including obesity, type 2 diabetes, and nonalcoholic fatty liver diseases (NAFLD), the involved mechanisms are still poorly described. Here, we show that, in both humans and mice, the pathogenesis of NAFLD is associated with the disruption of the circadian clock combined with perturbations of the growth hormone and sex hormone pathways. However, while this condition protects mice from the development of fibrosis and insulin resistance, it correlates with increased fibrosis in humans. This suggests that the perturbation of the circadian clock and its associated disruption of the growth hormone and sex hormone pathways are critical for the pathogenesis of metabolic and liver diseases.


Asunto(s)
Factores de Transcripción ARNTL/fisiología , Relojes Circadianos , Resistencia a la Insulina , Enfermedad del Hígado Graso no Alcohólico/etiología , Factores de Transcripción ARNTL/genética , Animales , Dieta Alta en Grasa , Eliminación de Gen , Regulación de la Expresión Génica , Humanos , Leptina/genética , Metabolismo de los Lípidos/genética , Masculino , Ratones , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/genética , Obesidad/genética
13.
J Biol Chem ; 299(6): 104784, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37146972

RESUMEN

High dietary fat intake is associated with metabolic dysregulation, but little is known regarding the effects of a high fat diet (HFD) on photoreceptor cell functioning. We explored the intersection of an HFD and the visual cycle adducts that form in photoreceptor cells by nonenzymatic reactions. In black C57BL/6J mice and albino C57BL/6Jc2j mice raised on an HFD until age 3, 6, or 12 months, chromatographically quantified bisretinoids were increased relative to mice on a standard diet. In vivo measurement of fundus autofluorescence, the source of which is bisretinoid, also revealed a significant increase in the HFD mice. Additionally, mice provided with a diet high in fat presented with elevated retinol-binding protein 4, the protein responsible for transporting retinol in plasma. Vitamin A was elevated in plasma although not in ocular tissue. Bisretinoids form in photoreceptor cell outer segments by random reactions of retinaldehyde with phosphatidylethanolamine. We found that the latter phospholipid was significantly increased in mice fed an HFD versus mice on a control diet. In leptin-deficient ob/ob mice, a genetic model of obesity, plasma levels of retinol-binding protein 4 were higher but bisretinoids in retina were not elevated. Photoreceptor cell viability measured as outer nuclear layer thickness was reduced in the ob/ob mice relative to WT. The accelerated formation of bisretinoid we observed in diet-induced obese mice is related to the high fat intake and to increased delivery of vitamin A to the visual cycle.


Asunto(s)
Dieta Alta en Grasa , Células Fotorreceptoras , Retinoides , Animales , Ratones , Dieta Alta en Grasa/efectos adversos , Leptina/genética , Leptina/metabolismo , Ratones Endogámicos C57BL , Ratones Obesos , Obesidad/metabolismo , Proteínas de Unión al Retinol/metabolismo , Vitamina A/metabolismo , Células Fotorreceptoras/citología , Células Fotorreceptoras/fisiología , Supervivencia Celular , Retinoides/metabolismo
14.
BMC Cancer ; 24(1): 937, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090596

RESUMEN

INTRODUCTION: Neuropeptide Y is a neurotransmitter in the nervous system and belongs to the orexigenic system that increases appetite. Its excessive secretion leads to obesity. Leptin is a pro-inflammatory adipokine (produced in adipose tissue) induced in obesity and may mediate increased antitumor immunity in obesity (including the promotion of M1 macrophages). Leptin and neuropeptide Y gene polymorphisms, causing increased leptin levels and the occurrence of obesity, and lipid profile disorders, may increase the effectiveness of immunotherapy. MATERIALS AND METHODS: In 121 patients with advanced NSCLC without mutations in the EGFR gene and rearrangements of the ALK and ROS1 genes, undergoing immunotherapy (1st and 2nd line of treatment) or chemoimmunotherapy (1st line of treatment), we assessed BMI, lipid profile, PD-L1 expression on cancer cells using the immunohistochemical method (clone SP263 antibody), leptin concentration in blood serum by ELISA, polymorphisms in the promoter region of the genes for leptin (LEP) and neuropeptide Y (NPY) by real-time PCR. RESULTS: Leptin concentration was significantly higher in obese patients than in patients with normal or low weight (p = 0.00003) and in patients with disease stabilization compared to patients with progression observed during immunotherapy (p = 0.012). Disease control occurred significantly more often in patients with the GA or AA genotype than patients with the GG genotype in the rs779039 polymorphism of the LEP gene. The median PFS in the entire study group was five months (95% CI: 3-5.5), and the median OS was 12 months (95% CI: 8-16). Median PFS was highest in patients with TPS ≥ 50% (6.5 months) and in obese patients (6.6 months). Obese patients also had a slightly longer median OS compared to other patients (23.8 vs. 13 months). The multivariate Cox logistic regression test showed that the only factor reducing the risk of progression was TPS ≥ 50% (HR = 0.6068, 95% CI: 0.4001-0.9204, p = 0, 0187), and the only factor reducing the risk of death was high leptin concentration (HR = 0.6743, 95% CI: 0.4243-1.0715, p = 0.0953). CONCLUSION: Assessment of nutritional status, serum leptin concentration and polymorphisms in the LEP gene may be of additional importance in predicting the effectiveness of immunotherapy and chemoimmunotherapy in patients with advanced NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Inmunoterapia , Leptina , Neoplasias Pulmonares , Neuropéptido Y , Estado Nutricional , Humanos , Leptina/genética , Leptina/sangre , Neuropéptido Y/genética , Masculino , Femenino , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/terapia , Persona de Mediana Edad , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Inmunoterapia/métodos , Anciano , Obesidad/genética , Adulto , Lípidos/sangre , Polimorfismo Genético , Antígeno B7-H1/genética , Resultado del Tratamiento , Anciano de 80 o más Años
15.
Diabetes Obes Metab ; 26 Suppl 2: 46-63, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38504134

RESUMEN

Over the past few decades, there has been a global surge in the prevalence of obesity, rendering it a globally recognized epidemic. Contrary to simply being a medical condition, obesity is an intricate disease with a multifactorial aetiology. Understanding the precise cause of obesity remains a challenge; nevertheless, there seems to be a complex interplay among biological, psychosocial and behavioural factors. Studies on the genetic factors of obesity have revealed several pathways in the brain that play a crucial role in food intake regulation. The best characterized pathway, thus far, is the leptin-melanocortin pathway, from which disruptions are responsible for the majority of monogenic obesity disorders. The effectiveness of conservative lifestyle interventions in addressing monogenic obesity has been limited. Therefore, it is crucial to complement the management strategy with pharmacological and surgical options. Emphasis has been placed on developing drugs aimed at replacing the absent signals, with the goal of restoring the pathway. In both monogenic and polygenic forms of obesity, outcomes differ across various interventions, likely due to the multifaceted nature of the disease. This underscores the need to explore alternative therapeutic strategies that can mitigate this heterogeneity. Precision medicine can be regarded as a powerful tool that can address this concern, as it values the understanding of the underlying abnormality triggering the disease and provides a tailored treatment accordingly. This would assist in optimizing outcomes of the current therapeutic approaches and even aid in the development of novel treatments capable of more effectively managing the global obesity epidemic.


Asunto(s)
Manejo de la Obesidad , Humanos , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/metabolismo , Medicina de Precisión , Obesidad/epidemiología , Obesidad/genética , Obesidad/terapia , Leptina/genética , Leptina/metabolismo , Melanocortinas/uso terapéutico , Melanocortinas/genética
16.
Br J Nutr ; 131(5): 737-748, 2024 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-37855224

RESUMEN

The aim of the present study was to investigate the relationship between leptin and adiponectin gene polymorphisms, circulating levels of leptin and adiponectin, adiposity and clinical markers in patients with myelodysplastic syndrome (MDS). This cross-sectional study was conducted with 102 adults and elderly MDS patients and 102 age- and sex-matched controls. Clinical characteristics, co-morbidities, anthropometric data, laboratory evaluation and genetic analysis (polymorphisms -2548G > A/rs7799039 of the LEP gene and +276G > T/rs1501299 of the ADIPOQ gene) were investigated. Serum leptin was higher and adiponectin lower in MDS when compared with controls. There was a significant positive correlation between serum leptin levels and BMI (r = 0·264, P = 0·025), waist circumference (r = 0·235, P = 0·047), body fat percentage (BF %) (r = 0·373, P = 0·001) and the fat mass index (FMI) (r = 0·371, P < 0·001). A lower mean adiponectin was found among patients with high BF %, higher visceral adiposity index and metabolic syndrome. A significant association was found between the AA genotype (mutant) of the LEP polymorphism rs7799039 and male sex and blast excess (≥ 5 %). In addition, a significant association was observed between the TT genotype (mutant) of the ADIPOQ rs1501299 polymorphism and Fe overload. These results demonstrate the importance of a comprehensive and systematic evaluation in patients with MDS in order to identify and control negative factors not related to the disease at an early stage.


Asunto(s)
Leptina , Síndromes Mielodisplásicos , Adulto , Anciano , Humanos , Masculino , Adipoquinas , Adiponectina/genética , Adiposidad/genética , Estudios Transversales , Leptina/genética , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/complicaciones , Obesidad/complicaciones , Polimorfismo de Nucleótido Simple
17.
Mol Biol Rep ; 51(1): 995, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39298063

RESUMEN

BACKGROUND: Cancer-associated fibroblasts, as a major component of the tumor microenvironment, have been shown to exhibit protumorigenic effects in pancreatic ductal adenocarcinoma. Moreover, cancer-associated fibroblasts-derived exosomes have been reported to promote tumor development, but exact mechanisms have not been elucidated. The purpose of this study was to investigate the processes by which exosomes generated from cancer-associated fibroblasts promote tumor growth. METHODS: twenty-one patients with pancreatic ductal adenocarcinoma who evaluated preoperatively as potentially surgically resectable without distant metastasis and pathologically examined postoperatively as pancreatic ductal cell carcinoma were included. We determined the expression of Leptin as well as downstream proteins at the clinical and cellular levels. Cancer-associated fibroblast-derived exosomes were characterised by nanoparticle transmission electron microscopy and tracking analysis. To ascertain the mechanism mediating the action of exosomal Leptin in pancreatic ductal adenocarcinoma, we performed CCK-8 assay, colony formation assays, transwell and wound healing assays in PSN1 cells to evaluate cell proliferation, migration and invasion. Western blotting was used to detect the level of Leptin, ABL2 and exosome markers. qRT-PCR was employed to evaluate miR-224-3p. Cancer-associated fibroblasts markers and exosome uptake were verified by immunofluorescence. RESULTS: Western blotting assays show that Leptin is present inside tissues and cancer-associated fibroblasts in pancreatic ductal adenocarcinoma. Cancer-associated fibroblasts stimulated PSN1 cells growth, migration and invasion in vitro by secreting the exosomal Leptin. Exosomal Leptin could regulate miR-224-3p, which targets negative regulation of ABL2. Inhibiting Leptin significantly limited PSN1 cells growth, migration and invasion. In vitro analyses revealed that miR-224-3p mimics mitigate the inhibitory effect of cancer-associated fibroblasts knockdown of Leptin on PSN1 cells development, but overexpression of ABL2 partly abolished the tumor-promoting phenotype of miR-224-3p mimics. CONCLUSION: Our results revealed that cancer-associated fibroblasts mediate pancreatic ductal adenocarcinoma development by regulating the miR-224-3p/ABL2 molecular axis through the secretion of the exosomal Leptin.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma Ductal Pancreático , Movimiento Celular , Proliferación Celular , Exosomas , Regulación Neoplásica de la Expresión Génica , Leptina , MicroARNs , Neoplasias Pancreáticas , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Exosomas/metabolismo , Exosomas/genética , Leptina/metabolismo , Leptina/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Fibroblastos Asociados al Cáncer/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Masculino , Femenino , Persona de Mediana Edad , Línea Celular Tumoral , Proliferación Celular/genética , Movimiento Celular/genética , Anciano , Microambiente Tumoral/genética
18.
Nutr Metab Cardiovasc Dis ; 34(2): 360-368, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37949710

RESUMEN

BACKGROUND AND AIMS: Observational studies have suggested a relationship between leptin and risk of stroke. However, evidence for the association remains inconsistent, and whether the association reflects a causal relationship remains to be established. To clarify this relationship, we adopted a two-sample Mendelian randomization (MR) analysis to investigate whether leptin plays a causal role in the risk of stroke and its subtypes. METHODS AND RESULTS: Five independent single-nucleotide polymorphisms (SNPs) associated with the leptin level from genome-wide association studies (GWASs) of European individuals were selected. We performed an MR analysis using the inverse-variance-weighted (IVW) as primary method to examine the causal effects of leptin on ischemic stroke (IS). Moreover, MR-Egger intercept and Cochran's Q statistic were also performed to detect the pleiotropy or heterogeneity of our MR results. Genetically predicted circulating leptin level was not associated with ischemic stroke [odds ratio (OR): 1.48, 95% confidence interval (CI): 0.78-2.8, P = 0.22], large artery stroke (OR: 1.44, 95% CI: 0.39-5.25, P = 0.57), cardioembolic stroke (OR:1.33, 95% CI: 0.55-3.22, P = 0.52), and small vessel stroke (OR: 1.48, 95% CI: 0.39-5.63, P = 0.56) using the IVW method. Likewise, there is no convincing evidence for the associations between leptin levels and cardiovascular diseases (CVD) risk factors. CONCLUSIONS: This study did not provide evidence that leptin levels are associated with increased risk of stroke and its subtypes.


Asunto(s)
Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Estudio de Asociación del Genoma Completo , Leptina/genética , Análisis de la Aleatorización Mendeliana , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/genética
19.
Endocr Regul ; 58(1): 153-157, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-39121476

RESUMEN

Objective. Genetic factors substantially contribute to the development and duration of arterial hypertension. The study of the A1166C polymorphism of the angiotensin II type 1 receptor gene (AGTR1) in arterial hypertension is an auspicious area for assessing the relationship between heredity, hypertension development, and adipokines, but it still remains debatable. The purpose of the current study was to investigate serum adipokines levels depending on the AGTR1 A1166C polymorphism. Methods. A total of 86 patients with arterial hypertension were examined, who underwent the evaluation of the allelic A1166C polymorphism of AGTR1 by polymerase chain reaction with electrophoretic detection and determination of serum adipokines levels using enzyme-linked immunosorbent assay. Results. In the group of patients with arterial hypertension, a significant increase in serum adipokines (resistin, adiponectin, and leptin) levels was found against the background of a decrease in the antianorexic hormone ghrelin with a predominance of CC genotype carriers compared with AA genotype carriers of the AGTR1. A statistically significant decrease in ghrelin and an increase in serum adipokines (resistin, adiponectin, and leptin) in CC genotype carriers compared with AA genotype carriers of the AGTR1 were found suggesting that CC genotype carriers may be predictors of the development of arterial hypertension in our patients. Conclusions. Statistically significant decrease in ghrelin and increase in serum adipokines (resistin, adiponectin, and leptin) were found in CC genotype carriers compared with AA genotype carriers of the AGTR1, which suggests that carriers of the CC genotype are predictors of the arterial hypertension development in our patients.


Asunto(s)
Adipoquinas , Hipertensión , Receptor de Angiotensina Tipo 1 , Humanos , Receptor de Angiotensina Tipo 1/genética , Femenino , Masculino , Hipertensión/genética , Hipertensión/sangre , Persona de Mediana Edad , Adipoquinas/sangre , Adipoquinas/genética , Adulto , Leptina/sangre , Leptina/genética , Polimorfismo de Nucleótido Simple , Adiponectina/sangre , Adiponectina/genética , Anciano , Ghrelina/genética , Ghrelina/sangre , Genotipo , Predisposición Genética a la Enfermedad , Resistina/genética , Resistina/sangre
20.
Lipids Health Dis ; 23(1): 103, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615017

RESUMEN

BACKGROUND: Previous studies have demonstrated the relationship between adipocyte factors, insulin resistance, and other indicators with telomere length. However, these studies did not consider the influence of changes in different indicators on telomere length over time. Therefore, the aim of this study is to elucidate the impact of changes in adipocyte factors, HOMA-IR, and other indicators on the dynamic variation of telomere length. METHODS: The data were from a cohort study conducted in Ningxia, China. A total of 1624 subjects were analyzed. Adipokines and relative leukocyte telomere length (RLTL) were measured, and changes in Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Homeostatic Model Assessment for ß-Cell Function (HOMA-ß), and Quantitative Insulin Sensitivity Check Index (QUICKI) were calculated. Generalized linear models evaluated associations between changes in adipokines and RLTL changes. Furthermore, univariate analyses examined the effects of changes in adipokines and insulin resistance indicators on ΔRLTL. RESULTS: The research findings indicate that females generally have shorter telomeres compared to males. In comparison to the low-level group of Δleptin (LEP), the high-level group of ΔLEP shows a negative correlation with ΔRLTL (B=-1.32, 95% CI (-2.38, -0.27)). Even after multivariable adjustments, this relationship persists (B=-1.31, 95% CI (-2.24, -0.23)). Further analysis reveals that after adjusting for ΔHOMA-IR, ΔHOMA-ß, and ΔQUICKI, the high-level group of ΔLEP still exhibits a significant negative correlation with ΔRLTL (B=-1.37, 95% CI (-2.43, -0.31)). However, the interaction effects between ΔHOMA-IR, ΔHOMA-ß, ΔQUICKI, and ΔLEP do not affect ΔRLTL. CONCLUSIONS: Elevated levels of leptin were significantly correlated with shortened telomere length. This suggests that increased leptin levels may impact overall individual health by affecting telomere length, underscoring the importance of measures to reduce leptin levels to mitigate the onset and progression of related diseases.


Asunto(s)
Resistencia a la Insulina , Leptina , Femenino , Masculino , Humanos , Leptina/genética , Estudios de Cohortes , Resistencia a la Insulina/genética , Población Rural , Acortamiento del Telómero , Telómero/genética , Adipoquinas , China , Leucocitos
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