RESUMEN
Early life stress (ELS) is defined as an acute or chronic stressor that negatively impacts a child's development. ELS is associated with substance use and mental health problems. This narrative literature review focuses on sex and gender differences in the effects of ELS on 1) adolescent neuroendocrine development; 2) pubertal brain maturation; and 3) development of internalizing symptoms and subsequent substance use. We posit that ELS may generate larger hormonal dysregulation in females than males during puberty, increasing internalizing symptoms and substance use. Future research should consider sex and gender differences in neuroendocrine developmental processes when studying the link between ELS and negative health outcomes.
Asunto(s)
Sistemas Neurosecretores , Caracteres Sexuales , Estrés Psicológico , Trastornos Relacionados con Sustancias , Humanos , Trastornos Relacionados con Sustancias/fisiopatología , Adolescente , Sistemas Neurosecretores/metabolismo , Masculino , Femenino , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Experiencias Adversas de la Infancia , Desarrollo del Adolescente/fisiologíaRESUMEN
Bilateral adrenalectomy (BLA) is a treatment option for patients with Cushing's Disease (CD) if transsphenoidal pituitary surgery fails or is not a therapeutic option. For most patients, BLA eliminates endogenous glucocorticoid and mineralocorticoid production, but for a small number of patients, endogenous secretion of adrenal hormones from adrenal tissue continues or recurs, leading to signs and symptoms of hypercortisolism. If adrenal tissue is confined to the adrenal bed, it is considered adrenal remnant tissue, while if it is outside the adrenal bed, it is considered adrenal rest tissue. We retrospectively evaluated morning serum cortisol, nighttime serum cortisol, nighttime salivary cortisol, and 24-h urine free cortisol on at least three occasions in 10 patients suspected of having endogenous cortisol production. Imaging of adrenal remnant tissue was also reviewed. Ten of 51 patients who underwent BLA during this time period had adrenal remnant/rest tissue marked by detectable endogenous glucocorticoid production; 9 of the 10 patients had signs and symptoms of hypercortisolism. Localization and treatment proved difficult. We conclude that the incidence of adrenal remnant/rest tissue in those undergoing BLA following unsuccessful pituitary surgery was 12% although there may have been a selection bias affecting this prevalence. The first indication of remnant tissue occurrence is a reduction in glucocorticoid replacement with symptoms of hypercortisolism. If this occurs, endogenous cortisol production should be tested for by cortisol measurements using a highly specific cortisol assay while the patient is taking dexamethasone or no glucocorticoid replacement. Endocrinologists need to monitor the development of both adrenal remnant tissue and Nelson's syndrome following BLA.
Asunto(s)
Glándulas Suprarrenales/metabolismo , Síndrome de Cushing/cirugía , Glándulas Suprarrenales/cirugía , Adrenalectomía , Adulto , Síndrome de Cushing/sangre , Síndrome de Cushing/orina , Femenino , Humanos , Hidrocortisona/sangre , Hidrocortisona/orina , Masculino , Persona de Mediana Edad , Hipófisis/metabolismo , Hipófisis/cirugía , Estudios Retrospectivos , Adulto JovenRESUMEN
Epidemiological studies have shown an increased risk of cardiovascular diseases in children born to mothers who smoked during pregnancy. The cardiovascular risk in the offspring associated with in utero nicotine exposure is further exaggerated by maternal obesity. The consumption of electronic cigarettes (e-cigarettes) is alarmingly increasing among adolescents and young adults without the knowledge of their harmful health effects. There has also been a substantial increase in e-cigarette use by women of reproductive age. This study investigates the detrimental effects of gestational exposure of e-cigarette and a high-fat diet (HFD) on neonatal hearts. Time-mated pregnant mice were fed a HFD and exposed to saline or e-cigarette aerosol with 2.4% nicotine from embryonic day 4 (E4) to E20. We demonstrated that in utero exposure of e-cigarettes and HFD from E4 to E20 triggers cardiomyocyte (CM) apoptosis in the offspring at postnatal day1 (PND1), PND3, and PND14. Induction of CM apoptosis following gestational exposure of e-cigarettes and HFD was associated with inactivation of AMP-activated protein kinase (AMPK), increased cardiac oxidative stress coupled with perturbation of cardiac BAX/BCL-2 ratio and activation of caspase 3 at PND 14. Electron microscopy further revealed that left ventricles of pups at PND14 after e-cigarette exposure exhibited apoptotic nuclei, convoluted nuclear membranes, myofibrillar derangement, and enlarged mitochondria occasionally showing signs of crystolysis, indicative of cardiomyopathy and cardiac dysfunction. Our results show profound adverse effects of prenatal exposure of e-cigarette plus HFD in neonatal hearts that may lead to long-term adverse cardiac consequences in the adult.
Asunto(s)
Apoptosis , Dieta Alta en Grasa/efectos adversos , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Miocitos Cardíacos/patología , Nicotina/toxicidad , Efectos Tardíos de la Exposición Prenatal/patología , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Animales Recién Nacidos , Femenino , Masculino , Ratones , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Nicotina/análisis , Estrés Oxidativo , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/metabolismoRESUMEN
The use of electronic nicotine delivery systems (ENDS), also known as e-cigarettes, with a variety of e-liquids/e-juices, is increasing at an alarming rate among adolescents who do not realize the potential harmful health effects. This study examines the harmful effects of ENDS on the liver. Apolipoprotein E null (ApoE-/-) mice on a western diet (WD) were exposed to saline or ENDS with 2.4% nicotine aerosol for 12 weeks using our mouse ENDS exposure model system, which delivers nicotine to mice and leads to equivalent serum cotinine levels found in human cigarette users. ApoE-/- mice on a WD exposed to ENDS exhibited a marked increase in hepatic lipid accumulation compared with ApoE-/- on a similar diet exposed to saline aerosol. The detrimental effects of ENDS on hepatic steatosis were associated with significantly greater oxidative stress, increased hepatic triglyceride levels, and increased hepatocyte apoptosis, independent of adenosine monophosphate-activated protein kinase signaling. In addition, hepatic RNA sequencing analysis revealed that 433 genes were differentially expressed in ENDS-exposed mice on WD compared with saline-exposed mice. Functional analysis indicates that genes associated with lipid metabolism, cholesterol biosynthesis, and circadian rhythm were most significantly altered in the liver in response to ENDS. Conclusion: These results demonstrate profound adverse effects of ENDS on the liver. This is important information for regulatory agencies as they regulate ENDS.
Asunto(s)
Cotinina/sangre , Dieta Occidental/efectos adversos , Sistemas Electrónicos de Liberación de Nicotina , Hígado Graso/etiología , Cirrosis Hepática/etiología , Análisis de Varianza , Animales , Biopsia con Aguja , Western Blotting , Modelos Animales de Enfermedad , Hígado Graso/patología , Humanos , Inmunohistoquímica , Cirrosis Hepática/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Estrés Oxidativo , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa/métodosRESUMEN
Electronic cigarettes (e-cigarettes), also known as electronic nicotine delivery systems, are a popular alternative to conventional nicotine cigarettes, both among smokers and those who have never smoked. In spite of the widespread use of e-cigarettes and the proposed detrimental cardiac and atherosclerotic effects of nicotine, the effects of e-cigarettes on these systems are not known. In this study, we investigated the cardiovascular and cardiac effects of e-cigarettes with and without nicotine in apolipoprotein-E knockout (ApoE-/-) mice. We developed an e-cigarette exposure model that delivers nicotine in a manner similar to that of human e-cigarettes users. Using commercially available e-cigarettes, bluCig PLUS, ApoE-/- mice were exposed to saline, e-cigarette without nicotine [e-cigarette (0%)], and e-cigarette with 2.4% nicotine [e-cigarette (2.4%)] aerosol for 12 wk. Echocardiographic data show that mice treated with e-cigarette (2.4%) had decreased left ventricular fractional shortening and ejection fraction compared with e-cigarette (0%) and saline. Ventricular transcriptomic analysis revealed changes in genes associated with metabolism, circadian rhythm, and inflammation in e-cigarette (2.4%)-treated ApoE-/- mice. Transmission electron microscopy revealed that cardiomyocytes of mice treated with e-cigarette (2.4%) exhibited ultrastructural abnormalities indicative of cardiomyopathy. Additionally, we observed increased oxidative stress and mitochondrial DNA mutations in mice treated with e-cigarette (2.4%). ApoE-/- mice on e-cigarette (2.4%) had also increased atherosclerotic lesions compared with saline aerosol-treated mice. These results demonstrate adverse effects of e-cigarettes on cardiac function in mice.NEW & NOTEWORTHY The present study is the first to show that mice exposed to nicotine electronic cigarettes (e-cigarettes) have decreased cardiac fractional shortening and ejection fraction in comparison with controls. RNA-seq analysis reveals a proinflammatory phenotype induced by e-cigarettes with nicotine. We also found increased atherosclerosis in the aortic root of mice treated with e-cigarettes with nicotine. Our results show that e-cigarettes with nicotine lead to detrimental effects on the heart that should serve as a warning to e-cigarette users and agencies that regulate them.
Asunto(s)
Aterosclerosis/etiología , Sistemas Electrónicos de Liberación de Nicotina , Nicotina/toxicidad , Agonistas Nicotínicos/toxicidad , Volumen Sistólico , Vapeo/efectos adversos , Disfunción Ventricular Izquierda/etiología , Función Ventricular Izquierda , Animales , Aterosclerosis/genética , Aterosclerosis/metabolismo , Aterosclerosis/patología , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Modelos Animales de Enfermedad , Exposición por Inhalación/efectos adversos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Mutación , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/ultraestructura , Estrés Oxidativo , Placa Aterosclerótica , Especies Reactivas de Oxígeno/metabolismo , Transcriptoma , Disfunción Ventricular Izquierda/genética , Disfunción Ventricular Izquierda/metabolismo , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
Excessive glucocorticoid (GC) production in adipose tissue promotes the development of visceral obesity and metabolic syndrome (MS). 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) is critical for controlling intracellular GC production, and this process is tightly regulated by hexose-6-phosphate dehydrogenase (H6PDH). To better understand the integrated molecular physiological effects of adipose H6PDH, we created a tissue-specific knockout of the H6PDH gene mouse model in adipocytes (adipocyte-specific conditional knockout of H6PDH (H6PDHAcKO) mice). H6PDHAcKO mice exhibited almost complete absence of H6PDH expression and decreased intra-adipose corticosterone production with a reduction in 11ß-HSD1 activity in adipose tissue. These mice also had decreased abdominal fat mass, which was paralleled by decreased adipose lipogenic acetyl-CoA carboxylase (ACC) and ATP-citrate lyase (ACL) gene expression and reduction in their transcription factor C/EBPα mRNA levels. Moreover, H6PDHAcKO mice also had reduced fasting blood glucose levels, increased glucose tolerance, and increased insulin sensitivity. In addition, plasma free fatty acid (FFA) levels were decreased with a concomitant decrease in the expression of lipase adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) in adipose tissue. These results indicate that inactivation of adipocyte H6PDH expression is sufficient to cause intra-adipose GC inactivation that leads to a favorable pattern of metabolic phenotypes. These data suggest that H6PDHAcKO mice may provide a good model for studying the potential contributions of fat-specific H6PDH inhibition to improve the metabolic phenotype in vivo. Our study suggests that suppression or inactivation of H6PDH expression in adipocytes could be an effective intervention for treating obesity and diabetes.
Asunto(s)
Tejido Adiposo/enzimología , Adiposidad , Deshidrogenasas de Carbohidratos/metabolismo , Glucocorticoides/metabolismo , Metabolismo de los Lípidos , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Animales , Glucemia , Deshidrogenasas de Carbohidratos/genética , Corticosterona/metabolismo , Ácidos Grasos no Esterificados/sangre , Resistencia a la Insulina , Ratones NoqueadosRESUMEN
BACKGROUND: Visceral fat accumulation increases the risk of developing type 2 diabetes and metabolic syndrome, and is associated with excessive glucocorticoids (GCs). Fat depot-specific GC action is tightly controlled by 11ß-hydroxysteroid dehydrogenase (11ß-HSD1) coupled with the enzyme hexose-6-phosphate dehydrogenase (H6PDH). Mice with inactivation or activation of H6PDH genes show altered adipose 11ß-HSD1 activity and lipid storage. We hypothesized that adipose tissue H6PDH activation is a leading cause for the visceral obesity and insulin resistance. Here, we explored the role and possible mechanism of enhancing adipose H6PDH in the development of visceral adiposity in vivo. METHODS: We investigated the potential contribution of adipose H6PDH activation to the accumulation of visceral fat by characterization of visceral fat obese gene expression profiles, fat distribution, adipocyte metabolic molecules, and abdominal fat-specific GC signaling mechanisms underlying the diet-induced visceral obesity and insulin resistance in H6PDH transgenic mice fed a standard of high-fat diet (HFD). RESULTS: Transgenic H6PDH mice display increased abdominal fat accumulation, which is paralleled by elevated lipid synthesis associated with induction of lipogenic transcriptor C/EBPα and PPARγ mRNA levels within adipose tissue. Transgenic H6PDH mice fed a high-fat diet (HFD) gained more abdominal visceral fat mass coupled with activation of GSK3ß and induction of XBP1/IRE1α, but reduced pThr308 Akt/PKB content and browning gene CD137 and GLUT4 mRNA levels within the visceral adipose tissue than WT controls. HFD-fed H6PDH transgenic mice also had impaired insulin sensitivity and exhibited elevated levels of intra-adipose GCs with induction of adipose 11ß-HSD1. CONCLUSION: These data provide the first in vivo mechanistic evidence for the adverse metabolic effects of adipose H6PDH activation on visceral fat distribution, fat metabolism, and adipocyte function through enhancing 11ß-HSD1-driven intra-adipose GC action.
Asunto(s)
Tejido Adiposo/enzimología , Deshidrogenasas de Carbohidratos/metabolismo , Obesidad Abdominal/metabolismo , Adipocitos/metabolismo , Tejido Adiposo/citología , Tejido Adiposo/metabolismo , Animales , Deshidrogenasas de Carbohidratos/análisis , Deshidrogenasas de Carbohidratos/genética , Dieta Alta en Grasa , Masculino , Ratones , Ratones Transgénicos , Obesidad Abdominal/genética , Transcriptoma/genéticaRESUMEN
We previously reported on the lack of utility of the 1 mg overnight dexamethasone (DEX) test in mild and/or periodic Cushing's syndrome, as most patients with the condition suppressed to 1 mg DEX. It is possible that a lower dose of DEX as part of an overnight DEX test might be able to distinguish between mild and/or periodic Cushing's syndrome and those without the condition. The objective of the current study is to determine the sensitivity and specificity of a 0.25 mg overnight DEX suppression test, the standard 1 mg overnight DEX suppression test, and the two-day low-dose (Liddle test) DEX suppression test with and without correction for DEX levels in patients evaluated for mild and/or periodic Cushing's syndrome. Thirty patients determined to have Cushing's syndrome by biochemical testing and 14 patients determined not to have the condition had the 0.25 mg and standard 1 mg overnight DEX suppression test and the two-day low-dose DEX suppression tests. Our results show that morning serum cortisol and cortisol/DEX ratios following an overnight dexamethasone suppression test were similar in patients with Cushing's syndrome and those not having Cushing's syndrome. However, a morning cortisol value above 7.6 µg/dl following a dose of DEX of 0.25 mg was found in 12 patients with Cushing's syndrome and none in those not having Cushing's syndrome, suggesting that a high cortisol value after this low dose of dexamethasone can indicate that further testing for Cushing's syndrome is warranted. Our data suggest that the traditional 1 mg overnight or the 2 mg/2 day DEX suppression testing should no longer be used as a screening test in patients who could have mild and/or periodic Cushing's syndrome, while the 0.25 mg dose of DEX may pick up some patients with mild Cushing's syndrome.
Asunto(s)
Síndrome de Cushing/tratamiento farmacológico , Dexametasona/uso terapéutico , Adolescente , Adulto , Síndrome de Cushing/sangre , Dexametasona/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hidrocortisona/sangre , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Cigarette smoking is an important risk factor for diabetes, cardiovascular disease and non-alcoholic fatty liver disease. The health risk associated with smoking can be aggravated by obesity. Smoking might also trigger cardiomyocyte (CM) apoptosis. Given that CM apoptosis has been implicated as a potential mechanism in the development of cardiomyopathy and heart failure, we characterize the key signaling pathways in nicotine plus high-fat diet (HFD)-induced CM apoptosis. Adult C57BL6 male mice were fed a normal diet (ND) or HFD and received twice-daily intraperitoneal (IP) injections of nicotine (0.75 mg/kg body weight [BW]) or saline for 16 weeks. An additional group of nicotine-treated mice on HFD received twice-daily IP injections of mecamylamine (1 mg/kg BW), a non-selective nicotinic acetylcholine receptor antagonist, for 16 weeks. Nicotine when combined with HFD led to a massive increase in CM apoptosis that was fully prevented by mecamylamine treatment. Induction of CM apoptosis was associated with increased oxidative stress and activation of caspase-2-mediated intrinsic pathway signaling coupled with inactivation of AMP-activated protein kinase (AMPK). Furthermore, nicotine treatment significantly (P < 0.05) attenuated the HFD-induced decrease in fibroblast growth factor 21 (FGF21) and silent information regulator 1 (SIRT1). We conclude that nicotine, when combined with HFD, triggers CM apoptosis through the generation of oxidative stress and inactivation of AMPK together with the activation of caspase-2-mediated intrinsic apoptotic signaling independently of FGF21 and SIRT1.
Asunto(s)
Apoptosis/efectos de los fármacos , Dieta Alta en Grasa , Miocitos Cardíacos/citología , Nicotina/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Caspasas/metabolismo , Factores de Crecimiento de Fibroblastos/metabolismo , Inmunohistoquímica , Masculino , Ratones Endogámicos C57BL , Modelos Biológicos , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/ultraestructura , Estrés Oxidativo/efectos de los fármacos , Fosforilación/efectos de los fármacos , Sirtuina 1/metabolismoRESUMEN
Long-term glucocorticoid exposure increases the risk for developing type 2 diabetes. Prereceptor activation of glucocorticoid availability in target tissue by 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) coupled with hexose-6-phosphate dehydrogenase (H6PDH) is an important mediator of the metabolic syndrome. We explored whether the tissue-specific modulation of 11ß-HSD1 and H6PDH in adipose tissue mediates glucocorticoid-induced insulin resistance and lipolysis and analyzed the effects of 11ß-HSD1 inhibition on the key lipid metabolism genes and insulin-signaling cascade. We observed that corticosterone (CORT) treatment increased expression of 11ß-HSD1 and H6PDH and induced lipase HSL and ATGL with suppression of p-Thr(172) AMPK in adipose tissue of C57BL/6J mice. In contrast, CORT induced adipose insulin resistance, as reflected by a marked decrease in IR and IRS-1 gene expression with a reduction in p-Thr(308) Akt/PKB. Furthermore, 11ß-HSD1 shRNA attenuated CORT-induced 11ß-HSD1 and lipase expression and improved insulin sensitivity with a concomitant stimulation of pThr(308) Akt/PKB and p-Thr(172) AMPK within adipose tissue. Addition of CORT to 3T3-L1 adipocytes enhanced 11ß-HSD1 and H6PDH and impaired p-Thr(308) Akt/PKB, leading to lipolysis. Knockdown of 11ß-HSD1 by shRNA attenuated CORT-induced lipolysis and reversed CORT-mediated inhibition of pThr(172) AMPK, which was accompanied by a parallel improvement of insulin signaling response in these cells. These findings suggest that elevated adipose 11ß-HSD1 expression may contribute to glucocorticoid-induced insulin resistance and adipolysis.
Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Grasa Abdominal/efectos de los fármacos , Grasa Abdominal/metabolismo , Glucocorticoides/farmacología , Resistencia a la Insulina , Lipólisis , ARN Interferente Pequeño/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Adipocitos/fisiología , Animales , Corticosterona/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Resistencia a la Insulina/genética , Lipólisis/efectos de los fármacos , Lipólisis/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Interferencia de ARNRESUMEN
The prereceptor activation of glucocorticoid production in adipose tissue by NADPH-dependent 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) has emerged as a potential mechanism in the pathogenesis of visceral obesity and metabolic syndrome. Hexose-6-phosphate dehydrogenase (H6PDH) is an endoplasmic reticulum lumen-resident enzyme that generates cofactor NADPH and thus mediates 11ß-HSD1 activity. To determine the role of adipose H6PDH in the prereceptor modulation of 11ß-HSD1 and metabolic phenotypes, we generated a transgenic (Tg) mouse model overexpressing H6PDH under the control of the enhancer-promoter region of the adipocyte fatty acid-binding protein (aP2) gene (aP2/H6PDH Tg mice). Transgenic aP2/H6PDH mice exhibited relatively high expression of H6PDH and elevated corticosterone production with induction of 11ß-HSD1 activity in adipose tissue. This increase in corticosterone production in aP2-H6PDH Tg mice resulted in mild abdominal fat accumulation with induction of C/EBP mRNA expression and slight weight gain. Transgenic aP2/H6PDH mice also exhibited fasting hyperglycemia and glucose intolerance with insulin resistance. In addition, the aP2/H6PDH Tg mice have elevated circulating free fatty acid levels with a concomitant increased adipose lipolytic action associated with elevated HSL mRNA and Ser(660) HSL phosphorylation within abdominal fat. These results suggest that increased H6PDH expression specifically in adipose tissue is sufficient to cause intra-adipose glucocorticoid production and adverse metabolic phenotypes. These findings suggest that the aP2/H6PDH Tg mice may provide a favorable model for studying the potential impact of H6PDH in the pathogenesis of human metabolic syndrome.
Asunto(s)
Tejido Adiposo/metabolismo , Deshidrogenasas de Carbohidratos/metabolismo , Glucocorticoides/biosíntesis , Lipólisis/fisiología , Adiposidad , Animales , Deshidrogenasas de Carbohidratos/genética , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Resistencia a la Insulina , Hígado/metabolismo , Masculino , Ratones , Ratones TransgénicosRESUMEN
Patients with diabetes display a heightened propensity to use tobacco; however, it is unclear whether they experience enhanced rewarding effects of nicotine. Thus, this study examined the reinforcing effects of nicotine in a rodent model of diabetes involving administration of streptozotocin (STZ), a drug that is toxic to pancreatic insulin-producing cells. The first study compared STZ- and vehicle-treated rats that had 23-hour access to intravenous self-administration (IVSA) of nicotine or saline and concomitant access to food and water. In order to examine the contribution of dopamine to our behavioral effects, dopamine transporter (DAT), D1 and D2 receptor levels were compared in the nucleus accumbens (NAc) following 10 days of nicotine or saline IVSA. Dopamine levels in the NAc were also compared following nicotine administration. Lastly, nicotine metabolism and dose-dependent effects of nicotine IVSA were assessed. The results revealed that STZ-treated rats displayed enhanced nicotine intake and a robust increase in food and water intake relative to controls. Protein analysis revealed an increase in DAT and a decrease in D1 receptor levels in the NAc of STZ- versus vehicle-treated rats regardless of IVSA condition. STZ-treated rats also displayed suppressed NAc dopamine levels during baseline and in response to nicotine. STZ treatment did not alter our assessment of nicotine metabolism. Furthermore, STZ treatment increased nicotine IVSA in a dose-dependent manner. Our findings suggest that STZ-treatment increased the rewarding effects of nicotine. This suggests that strong reinforcing effects of nicotine may contribute to greater tobacco use in patients with diabetes.
Asunto(s)
Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Recompensa , Animales , Glucemia/metabolismo , Condicionamiento Operante/efectos de los fármacos , Diabetes Mellitus Experimental , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/antagonistas & inhibidores , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Relación Dosis-Respuesta a Droga , Infusiones Intravenosas , Masculino , Nicotina/farmacocinética , Agonistas Nicotínicos/farmacocinética , Núcleo Accumbens/metabolismo , Ratas Wistar , Refuerzo en Psicología , AutoadministraciónRESUMEN
Introduction: Cigarettes containing nicotine (Nic) are a risk factor for the development of cardiovascular and metabolic diseases. We reported that Nic delivered via injections or e-cigarette vapor led to hepatic steatosis in mice fed with a high-fat diet. High-fructose corn syrup (HFCS) is the main sweetener in sugar-sweetened beverages (SSBs) in the US. Increased consumption of SSBs with HFCS is associated with increased risks of non-alcoholic fatty liver disease (NAFLD). Nicotinamide riboside (NR) increases mitochondrial nicotinamide adenine dinucleotide (NAD+) and protects mice against hepatic steatosis. This study evaluated if Nic plus Coca-Cola™ (Coke) with HFCS can cause hepatic steatosis and that can be protected by NR. Methods: C57BL/6J mice received twice daily intraperitoneal (IP) injections of Nic or saline and were given Coke (HFCS), or Coke with sugar, and NR supplementation for 10 weeks. Results: Our results show that Nic+Coke caused increased caloric intake and induced hepatic steatosis, and the addition of NR prevented these changes. Western blot analysis showed lipogenesis markers were activated (increased cleavage of the sterol regulatory element-binding protein 1 [SREBP1c] and reduction of phospho-Acetyl-CoA Carboxylase [p-ACC]) in the Nic+Coke compared to the Sal+Water group. The hepatic detrimental effects of Nic+Coke were mediated by decreased NAD+ signaling, increased oxidative stress, and mitochondrial damage. NR reduced oxidative stress and prevented mitochondrial damage by restoring protein levels of Sirtuin1 (Sirt1) and peroxisome proliferator-activated receptor coactivator 1-alpha (PGC1) signaling. Conclusion: We conclude that Nic+Coke has an additive effect on producing hepatic steatosis, and NR is protective. This study suggests concern for the development of NAFLD in subjects who consume nicotine and drink SSBs with HFCS.
Asunto(s)
Ratones Endogámicos C57BL , Niacinamida , Nicotina , Compuestos de Piridinio , Animales , Compuestos de Piridinio/farmacología , Ratones , Niacinamida/análogos & derivados , Niacinamida/farmacología , Masculino , Enfermedad del Hígado Graso no Alcohólico/prevención & control , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/etiología , Hígado Graso/prevención & control , Hígado Graso/metabolismo , Hígado Graso/inducido químicamente , Jarabe de Maíz Alto en Fructosa/efectos adversos , Hígado/metabolismo , Hígado/efectos de los fármacos , Hígado/patología , Estrés Oxidativo/efectos de los fármacosRESUMEN
AIMS/HYPOTHESIS: More than 90% of Chinese familial early-onset type 2 diabetes mellitus is genetically unexplained. To investigate the molecular aetiology, we identified and characterised whether mutations in the KCNJ11 gene are responsible for these families. METHODS: KCNJ11 mutations were screened for 96 familial early-onset type 2 diabetic probands and their families. Functional significance of the identified mutations was confirmed by physiological analysis, molecular modelling and population survey. RESULTS: Three novel KCNJ11 mutations, R27H, R192H and S116F117del, were identified in three families with early-onset type 2 diabetes mellitus. Mutated KCNJ11 with R27H or R192H markedly reduced ATP sensitivity (E23K>R27H>C42R>R192H>R201H), but no ATP-sensitive potassium channel currents were detected in the loss-of-function S116F117del channel in vitro. Molecular modelling indicated that R192H had a larger effect on the channel ATP-binding pocket than R27H, which may qualitatively explain why the ATP sensitivity of the R192H mutation is seven times less than R27H. The shape of the S116F117del channel may be compressed, which may explain why the mutated channel had no currents. Discontinuation of insulin and implementation of sulfonylureas for R27H or R192H carriers and continuation/switch to insulin therapy for S116F117del carriers resulted in good glycaemic control. CONCLUSIONS/INTERPRETATION: Our results suggest that genetic diagnosis for the KCNJ11 mutations in familial early-onset type 2 diabetes mellitus may help in understanding the molecular aetiology and in providing more personalised treatment for these specific forms of diabetes in Chinese and other Asian patients.
Asunto(s)
Pueblo Asiatico/genética , Diabetes Mellitus Tipo 2/genética , Canales KATP/genética , Mutación Missense , Canales de Potasio de Rectificación Interna/genética , Adolescente , Adulto , Anciano , Sustitución de Aminoácidos , Niño , Análisis Mutacional de ADN , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/genética , Humanos , Canales KATP/sangre , Masculino , Persona de Mediana Edad , LinajeRESUMEN
Type 2 diabetes mellitus (T2DM) and depression are significant public health and socioeconomic issues. They commonly co-occur, with T2DM occurring in 11.3% of the US population, while depression has a prevalence of about 9%, with higher rates among youths. Approximately 31% of patients with T2DM suffer from depressive symptoms, with 11.4% having major depressive disorders, which is twice as high as the prevalence of depression in patients without T2DM. Additionally, over 80% of people with T2DM are overweight or obese. This review describes how T2DM and depression can enhance one another, using the same molecular pathways, by synergistically altering the brain's structure and function and reducing the reward obtained from eating. In this article, we reviewed the evidence that eating, especially high-caloric foods, stimulates the limbic system, initiating Reward Deficiency Syndrome. Analogous to other addictive behaviors, neurochemical changes in those with depression and/or T2DM are thought to cause individuals to increase their food intake to obtain the same reward leading to binge eating, weight gain and obesity. Treating the symptoms of T2DM, such as lowering HbA1c, without addressing the underlying pathways has little chance of eliminating the disease. Targeting the immune system, stress circuit, melatonin, and other alterations may be more effective.
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Trastorno Depresivo Mayor , Diabetes Mellitus Tipo 2 , Melatonina , Adolescente , Humanos , Retroalimentación , Depresión , Obesidad/complicaciones , Sistema InmunológicoRESUMEN
Aim: Non-alcoholic fatty liver disease (NAFLD) exhibits a racial disparity. We examined the prevalence and the association between race, gender, and NAFLD among prediabetes and diabetes populations among adults in the United States. Methods: We analyzed data for 3,190 individuals ≥18 years old from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. NAFLD was diagnosed by FibroScan® using controlled attenuation parameter (CAP) values: S0 (none) < 238, S1 (mild) = 238-259, S2 (moderate) = 260-290, S3 (severe) > 290. Data were analyzed using Chi-square test and multinomial logistic regression, adjusting for confounding variables and considering the design and sample weights. Results: Of the 3,190 subjects, the prevalence of NAFLD was 82.6%, 56.4%, and 30.5% (p < 0.0001) among diabetes, prediabetes and normoglycemia populations respectively. Mexican American males with prediabetes or diabetes had the highest prevalence of severe NAFLD relative to other racial/ethnic groups (p < 0.05). In the adjusted model, among the total, prediabetes, and diabetes populations, a one unit increase in HbA1c was associated with higher odds of severe NAFLD [adjusted odds ratio (AOR) = 1.8, 95% confidence level (CI) = 1.4-2.3, p < 0.0001; AOR = 2.2, 95% CI = 1.1-4.4, p = 0.033; and AOR = 1.5, 95% CI = 1.1-1.9, p = 0.003 respectively]. Conclusion: We found that prediabetes and diabetes populations had a high prevalence and higher odds of NAFLD relative to the normoglycemic population and HbA1c is an independent predictor of NAFLD severity in prediabetes and diabetes populations. Healthcare providers should screen prediabetes and diabetes populations for early detection of NAFLD and initiate treatments including lifestyle modification to prevent the progression to non-alcoholic steatohepatitis or liver cancer.
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CARF (CDKN2AIP) regulates cellular fate in response to various stresses. However, its role in metabolic stress is unknown. We found that fatty livers from mice exhibit low CARF expression. Similarly, overloaded palmitate inhibited CARF expression in HepG2 cells, suggesting that excess fat-induced stress downregulates hepatic CARF. In agreement with this, silencing and overexpressing CARF resulted in higher and lower fat accumulation in HepG2 cells, respectively. Furthermore, CARF overexpression lowered the ectopic palmitate accumulation in HepG2 cells. We were interested in understanding the role of hepatic CARF and underlying mechanisms in the development of NAFLD. Mechanistically, transcriptome analysis revealed that endoplasmic reticulum (ER) stress and oxidative stress pathway genes significantly altered in the absence of CARF. IRE1α, GRP78, and CHOP, markers of ER stress, were increased, and the treatment with TUDCA, an ER stress inhibitor, attenuated fat accumulation in CARF-deficient cells. Moreover, silencing CARF caused a reduction of GPX3 and TRXND3, leading to oxidative stress and apoptotic cell death. Intriguingly, CARF overexpression in HFD-fed mice significantly decreased hepatic steatosis. Furthermore, overexpression of CARF ameliorated the aberrant ER function and oxidative stress caused by fat accumulation. Our results further demonstrated that overexpression of CARF alleviates HFD-induced insulin resistance assessed with ITT and GTT assay. Altogether, we conclude that excess fat-induced reduction of CARF dysregulates ER functions and lipid metabolism leading to hepatic steatosis.
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Proteínas Reguladoras de la Apoptosis , Endorribonucleasas , Enfermedad del Hígado Graso no Alcohólico , Proteínas de Unión al ARN , Animales , Ratones , Ácidos Grasos/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Palmitatos , Proteínas Serina-Treonina Quinasas , Humanos , Células Hep G2 , Proteínas Reguladoras de la Apoptosis/genética , Proteínas de Unión al ARN/genéticaRESUMEN
OBJECTIVES: Although public efforts to reduce tobacco use have been successful, millions of US adults currently smoke tobacco. Reducing the public health burden of tobacco use disorder (TUD) and eliminating disparities experienced by underresourced communities requires increased accessibility to services. The goal of this study was to assess whether prescriptions for evidence-based medications for tobacco treatment showed steeper growth rates among community health clinics providing specialty TUD services as compared with treatment as usual. METHODS: Clinic-wide data on prescriptions for smoking cessation pharmacotherapy at 18 primary care or mental health community clinics operated by Los Angeles County were retrieved for 4 years of an ongoing implementation trial. Specialty services included behavioral counseling and medications for tobacco treatment. Descriptive statistics characterized prescriptions rates across clinics and time. Analyses compared the slopes of the changes between intervention groups across time for primary care and mental health sites. RESULTS: Within primary care clinics, the most commonly prescribed smoking cessation medications were nicotine patches, nicotine gum, and varenicline. Throughout the trial, all clinics displayed increased rates of prescribing smoking cessation medications. Analytic results supported overall steeper increases in prescription rates for these medications among clinics randomized to specialty services versus treatment as usual within primary care ( P = 0.020) and mental health sites ( P = 0.004). CONCLUSIONS: This work provides support for the effectiveness of community-based implementation interventions that promote prescribing smoking cessation medications with the potential to reduce health disparities among communities at greater risk for TUD and its consequences.
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Cese del Hábito de Fumar , Tabaquismo , Adulto , Humanos , Salud Pública , Nicotina , Uso de TabacoRESUMEN
Electronic cigarettes (e-cigarettes) are a prevalent alternative to conventional nicotine cigarettes among smokers and people who have never smoked. Increased concentrations of serum free fatty acids (FFAs) are crucial in generating lipotoxicity. We studied the effects of acipimox, an antilipolytic drug, on e-cigarette-induced cardiac dysfunction. C57BL/6J wild-type mice on high fat diet were treated with saline, e-cigarette with 2.4% nicotine [e-cigarette (2.4%)], and e-cigarette (2.4%) plus acipimox for 12 weeks. Fractional shortening and ejection fraction were diminished in mice exposed to e-cigarettes (2.4%) compared with saline and acipimox-treated mice. Mice exposed to e-cigarette (2.4%) had increased circulating levels of inflammatory cytokines and FFAs, which were diminished by acipimox. Gene Set Enrichment Analysis revealed that e-cigarette (2.4%)-treated mice had gene expression changes in the G2/M DNA damage checkpoint pathway that was normalized by acipimox. Accordingly, we showed that acipimox suppressed the nuclear localization of phospho-p53 induced by e-cigarette (2.4%). Additionally, e-cigarette (2.4%) increased the apurinic/apyrimidinic sites, a marker of oxidative DNA damage which was normalized by acipimox. Mice exposed to e-cigarette (2.4%) had increased cardiac Heme oxygenase 1 protein levels and 4-hydroxynonenal (4-HNE). These markers of oxidative stress were decreased by acipimox. Therefore, inhibiting lipolysis with acipimox normalizes the physiological changes induced by e-cigarettes and the associated increase in inflammatory cytokines, oxidative stress, and DNA damage.
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Sistemas Electrónicos de Liberación de Nicotina , Humanos , Ratones , Animales , Nicotina , Lipólisis , Ratones Endogámicos C57BL , Fenotipo , CitocinasRESUMEN
Corticosterone-releasing hormone (CRH) and arginine vasopressin (AVP) are crucial components of the hypothalamic-pituitary-adrenal axis that stimulates the release of adrenocorticotropic hormone from the pituitary and mediate the stress response. CRH binds to two subtypes of CRH receptors (CRH-R1 and CRH-R2) that are present in both central and peripheral tissues. We used the CRH-R1-specific antagonist, antalarmin (ANT), the CRH-R1 and CRH-R2 peptide antagonist, astressin (AST), and the CRH-R2-specific peptide antagonist, astressin2b (AST2b), to determine which CRH receptor is involved in the nicotine-stimulated secretion of corticosterone. Male C57BL/6 mice were administered ANT (20 mg/kg, i.p.), AST (0.3 mg/kg, i.p.), AST2b (0.3 mg/kg, i.p.) or vehicle prior to administration of nicotine (1.0 mg/kg, s.c.), CRH (10 µg/kg, s.c.), AVP (10 µg/kg, s.c.) or saline (s.c.), killed 15 min later and trunk blood collected and assayed for corticosterone plasma levels. We found that CRH enhanced corticosterone release, and this response was blocked by both AST and ANT. Nicotine also increased corticosterone secretion, but this effect persisted in the presence of either CRH antagonist. Furthermore, AST but not ANT or AST2b decreased corticosterone levels associated with stress of handling and injection. We also assessed the role of AVP V(1b) -specific receptor antagonist, SSR149415 alone and in combination with AST and AST2b. Although the AVP antagonist did not alter basal or nicotine-stimulated corticosterone secretion, it attenuated the AVP-induced stimulation of corticosterone and its combination with AST but not AST2b completely abolished nicotine-mediated stimulation of corticosterone secretion. Our results demonstrate that the nicotine-induced stimulation of the hypothalamic-pituitary-adrenal axis is mediated by both the CRH-R and the AVP V(1b) receptor and when the CRH receptor is blocked, nicotine may utilize the AVP V(1b) receptor to mediate secretion of corticosterone. These results argue in favor of the development of specific antagonists that block both AVP and CRH receptors to decrease the pleasurable component of nicotine, which may be mediated by corticosterone.