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1.
J Neurosci ; 41(2): 354-365, 2021 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-33219004

RESUMEN

Drug addiction is a chronic disorder characterized by compulsive drug seeking, and involves repetitive cycles of compulsive drug use, abstinence, and relapse. In both human and animal models of addiction, chronic food restriction increases rates of relapse. Our laboratory has reported a robust increase in drug seeking following a period of withdrawal in chronically food-restricted rats compared with sated controls. Recently, we reported that activation of the paraventricular nucleus of the thalamus (PVT) abolished heroin seeking in chronically food-restricted rats. However, the precise inputs and outputs of the PVT that mediate this effect remain elusive. The goal of the current study was to determine the role of corticothalamic and thalamo-accumbens projections in the augmentation of heroin seeking induced by chronic food restriction. Male Long-Evans rats were trained to self-administer heroin for 10 d. Next, rats were removed from the self-administration chambers and were subjected to a 14 d withdrawal period while sated (unlimited access to food) or mildly food-restricted (FDR). On day 14, rats were returned to the self-administration context for a 3 h heroin-seeking test under extinction conditions during which corticothalamic and thalamo-accumbens neural activity was altered using chemogenetics. Surprisingly, chemogenetic activation or inhibition of corticothalamic projections did not alter heroin-seeking behavior. Chemogenetic activation of thalamo-accumbens shell, but not core, projectors attenuated heroin seeking in FDR rats. The results indicate an important role for the PVT to nucleus accumbens shell projections in the augmentation of heroin seeking induced by chronic food restriction.SIGNIFICANCE STATEMENT Relapse to heroin use is one of the major obstacles in the treatment of opiate addiction. Triggers for relapse are modulated by environmental challenges such as caloric restriction. Elucidating the brain mechanisms that underlie relapse is critical for evidence-based treatment development. Here we demonstrate a critical role for the input from the paraventricular thalamus (PVT), a hub for cortical, sensory, and limbic information, to the nucleus accumbens shell (an area known to be important for reward and motivation) in the augmentation of heroin seeking in food-restricted rats. Our findings highlight a previously unknown role for the PVT in heroin seeking following a period of abstinence.


Asunto(s)
Corteza Cerebral/fisiología , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Privación de Alimentos , Dependencia de Heroína/psicología , Vías Nerviosas/fisiología , Núcleo Accumbens/fisiología , Tálamo/fisiología , Animales , Conducta Adictiva/fisiopatología , Clozapina/farmacología , Heroína/farmacología , Masculino , Actividad Motora/efectos de los fármacos , Narcóticos/farmacología , Ratas , Ratas Long-Evans , Recurrencia , Autoadministración , Síndrome de Abstinencia a Sustancias/psicología
2.
Addict Biol ; 25(2): e12708, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-30623532

RESUMEN

Drug addiction is a chronic disorder that is characterized by compulsive drug seeking and involves cycling between periods of compulsive drug use, abstinence, and relapse. In both human addicts and animal models of addiction, chronic food restriction has been shown to increase rates of relapse. Previously, our laboratory has demonstrated a robust increase in drug seeking following a period of withdrawal in chronically food-restricted rats compared with sated rats. To date, the neural mechanisms that mediate the effect of chronic food restriction on drug seeking have not been elucidated. However, the paraventricular nucleus of the thalamus (PVT) appears to be a promising target to investigate. The objective of the current study was to examine the role of the PVT in the augmentation of heroin seeking induced by chronic food restriction. Male Long-Evans rats were trained to self-administer heroin for 10 days. Rats were then removed from the training chambers and experienced a 14-day withdrawal period with either unrestricted (sated) or mildly restricted (FDR) access to food. On day 14, rats underwent a 1-hour heroin-seeking test under extinction conditions, during which neural activity in the PVT was either inhibited or increased using pharmacological or chemogenetic approaches. Unexpectedly, inhibition of the PVT did not alter heroin seeking in food-restricted or sated rats, while enhancing neural activity in the PVT-attenuated heroin seeking in food-restricted rats. These results indicate that PVT activity can modulate heroin seeking induced by chronic food restriction.


Asunto(s)
Conducta Animal/efectos de los fármacos , Privación de Alimentos/fisiología , Dependencia de Heroína/fisiopatología , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Núcleo Hipotalámico Paraventricular/fisiopatología , Animales , Modelos Animales de Enfermedad , Heroína/farmacología , Dependencia de Heroína/psicología , Masculino , Ratas , Ratas Long-Evans
3.
Eur J Nutr ; 56(3): 1025-1036, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26746221

RESUMEN

PURPOSE: Previous studies have reported improvements in cardiovascular disease (CVD) risk factors with the consumption of raw nuts. However, around one-third of nuts consumed are roasted and salted. Thus, it is important to determine whether roasting and salting nuts affect the health benefits observed with raw nuts. This study aimed to compare the effects of consuming two different forms of hazelnuts on cardiovascular risk factors and acceptance. METHODS: Using a randomised crossover design, 72 participants were asked to consume 30 g/day of either raw or dry roasted, lightly salted hazelnuts for 28 days each. CVD risk factors were measured at the beginning and end of each treatment period. "Desire to consume" and "overall liking" for both forms of hazelnuts were assessed daily using a 150-mm visual analogue scale. RESULTS: Body composition, blood pressure, plasma total and low-density lipoprotein-cholesterol, apolipoprotein A1 and B100, glucose and α-tocopherol concentrations did not differ between forms of hazelnuts (all P ≥ 0.054). High-density lipoprotein (HDL)-cholesterol (P = 0.037) and triacylglycerol (P < 0.001) concentrations were significantly lower following the consumption of dry roasted, lightly salted hazelnuts when compared to the raw hazelnuts. Compared with baseline, consuming both forms of hazelnuts significantly improved HDL-cholesterol and apolipoprotein A1 concentrations, total-C/HDL-C ratio, and systolic blood pressure without significantly changing body composition. Acceptance ratings did not differ between forms of hazelnuts and remained high throughout the study. CONCLUSION: Dry roasting and lightly salting nuts do not appear to negate the cardioprotective effects observed with raw nut consumption, and both forms of nuts are resistant to monotony. Public health messages could be extended to include dry roasted and lightly salted nuts as part of a heart healthy diet.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Manipulación de Alimentos/métodos , Nueces , Cloruro de Sodio Dietético/administración & dosificación , Adulto , Apolipoproteína A-I/sangre , Glucemia/metabolismo , Presión Sanguínea , Composición Corporal , Índice de Masa Corporal , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Corylus , Estudios Cruzados , Dieta , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Ácidos Grasos/administración & dosificación , Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Insaturados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Factores de Riesgo , Triglicéridos/sangre , alfa-Tocoferol/sangre
4.
Eur J Nutr ; 56(3): 1255-1267, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26897125

RESUMEN

PURPOSE: Regular nut consumption reduces cardiovascular disease risk, partly from improvements to dietary quality. Examining how individuals make dietary changes when consuming nuts may reveal key behavioural eating patterns beneficial for the development of dietary interventions. We examined the effects of nuts in comparison with other energy-dense snacks on energy compensation, nutrient displacement, and food group patterns. METHODS: This was a 12-week randomised, controlled, parallel study with four arms: ~1100 kJ/day for each of hazelnuts (42 g), chocolate (50 g), potato crisps (50 g), or no added snack food. Diet records, body composition, and physical activity were measured at baseline and week 12, in 102 non-obese participants. RESULTS: Significant improvements in diet quality were observed in the hazelnut group, particularly when consumed as snacks. Intakes of monounsaturated fat (MUFA) and vitamin E were significantly higher (all P < 0.05), whereas saturated fat and carbohydrate were significantly lower (both P ≤ 0.022) in the hazelnut group compared to the other groups. Partial energy compensation did not differ significantly between groups, but nutrient displacement values for MUFA and fibre differed significantly. Within the hazelnut group, there was nearly complete displacement for fibre, partial displacement for energy, protein, total fat, MUFA, PUFA, potassium, folate, and vitamin E, and overcompensation for carbohydrate and sugar. CONCLUSIONS: Our results demonstrate that energy compensation occurs for all three intervention snacks in this non-obese population. Regular nut consumption significantly improves nutrient profiles compared to other snacks with changes occurring at the snack level.


Asunto(s)
Corylus/química , Dieta , Ingestión de Energía , Nueces/química , Bocadillos , Adolescente , Adulto , Anciano , Composición Corporal , Índice de Masa Corporal , Registros de Dieta , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Ejercicio Físico , Ácidos Grasos/administración & dosificación , Ácidos Grasos Monoinsaturados/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vitamina E/administración & dosificación , Adulto Joven
5.
Eur J Nutr ; 55(7): 2281-93, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26358166

RESUMEN

PURPOSE: Consuming 30 g of nuts/day is recommended to reduce chronic disease. However, nut consumption appears far from ideal among several populations. A potential strategy to increase consumption is to add nuts to a staple, for example, bread. Whether the health benefits and acceptability of nuts persist in this form is currently unknown. Thus, we examined the effects of consuming three nut-enriched breads on postprandial glycaemia, satiety, gastrointestinal tolerance, dietary intakes, and acceptance. METHODS: In this controlled, crossover study, 32 participants were randomly allocated to receive one of four breads for 8 days each. Three breads contained either 30 g of finely sliced hazelnuts, 30 g semi-defatted hazelnut flour, or 15 g of each (amounts per 120 g bread) and were compared with a control nut-free bread. Blood glucose response was measured over 120 min, along with ratings of gastrointestinal discomfort. Appetite ratings and diet diaries were completed during each treatment period. RESULTS: Area under the blood glucose curve was significantly lower for the nut breads compared to the control bread (all P < 0.001), with no significant differences between the nut breads (all P ≥ 0.130). There were no significant differences in satiety (all P ≥ 0.135) or gastrointestinal symptoms (all P ≥ 0.102) between the breads. Acceptance was highest for the finely sliced hazelnut bread. Furthermore, consuming hazelnut-enriched bread improved diet quality, increasing monounsaturated fat, vitamin E, and dietary fibre intakes. CONCLUSION: Bread appears to be an effective and acceptable vehicle for increasing nut consumption, resulting in improved postprandial glycaemia and diet profiles. Long-term studies are now required.


Asunto(s)
Pan/análisis , Manipulación de Alimentos , Nueces , Adolescente , Adulto , Anciano , Apetito , Glucemia/metabolismo , Comportamiento del Consumidor , Corylus , Estudios Cruzados , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/análisis , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/análisis , Fibras de la Dieta/administración & dosificación , Fibras de la Dieta/análisis , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/análisis , Ingestión de Energía , Ácidos Grasos/administración & dosificación , Ácidos Grasos/análisis , Ácidos Grasos Monoinsaturados/administración & dosificación , Ácidos Grasos Monoinsaturados/análisis , Ácidos Grasos Insaturados/administración & dosificación , Ácidos Grasos Insaturados/análisis , Femenino , Harina/análisis , Humanos , Masculino , Micronutrientes/administración & dosificación , Micronutrientes/análisis , Persona de Mediana Edad , Evaluación Nutricional , Periodo Posprandial , Saciedad , Gusto , Adulto Joven
6.
Eur J Nutr ; 54(3): 483-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25433502

RESUMEN

PURPOSE: Regular nut consumption is inversely associated with cardiovascular disease risk. No study has compared the effects of regular consumption of different types and forms of nuts on acceptance, which is a crucial determinant of long-term compliance to consume nuts regularly. METHODS: This study examined the effects of different types and forms of raw, unpeeled nuts on acceptance and the effects of nut consumption on blood lipids through a randomised crossover study with six dietary phases: 30 g/day of ground, sliced, or whole almonds or hazelnuts for 5 days each (n = 74). Acceptance ('desire' and 'liking') for nuts was measured daily using visual analogue scales. Blood lipids were measured at baseline and week 6. RESULTS: Acceptance was stable over all conditions, but there were differences between nut forms (ground < sliced < whole, P < 0.001 for both 'desire' and 'liking') with some nut type-nut form interactions. Compared with baseline, week 6 HDL-C was higher (0.06 mmol/L, 95% CI 0.02-0.10, P = 0.002) while LDL-C and total-C:HDL-C ratio were lower (0.15 mmol/L, 95% CI 0.06-0.25, P = 0.002 and 0.25, 95% CI 0.07-0.43, P = 0.006). CONCLUSIONS: In conclusion, acceptance was stable for all combinations but was highest for whole nuts. Six weeks of nut consumption improved blood lipids.


Asunto(s)
HDL-Colesterol/sangre , LDL-Colesterol/sangre , Dieta , Nueces , Triglicéridos/sangre , Adulto , Índice de Masa Corporal , Corylus , Estudios Cruzados , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Nutritivo , Prunus dulcis , Gusto , Resultado del Tratamiento , Adulto Joven
7.
Br J Nutr ; 112(12): 2028-40, 2014 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-25354462

RESUMEN

Regular nut consumption is associated with reduced CVD risk. Insight into nut consumption patterns provides important information to help design strategies to encourage intake. The present study aimed to describe nut consumption in terms of the percentage of consumers, mean grams eaten among the population and nut consumers, and to identify the predictors of nut consumption. Data from the 24 h dietary recalls of the 2008/09 New Zealand Adult Nutrition Survey (n 4721) were used to measure nut consumption. On the recall day, the percentages of consumers of whole nuts, nut butters and nuts from hidden sources were 6.9% (n 240), 7.2% (n 346) and 19.2% (n 732), respectively (28.9% (n 1167) combined (total)). The mean grams consumed by the population were relatively low for whole nuts (2.8 g/d), nut butters (0.9 g/d), nuts from hidden sources (1.5 g/d) and total nuts (5.2 g/d). Among consumers, the mean daily grams of whole nuts, nut butters, nuts from hidden sources and total nuts eaten were 40.3, 12.9, 7.8 and 17.9 g/d, respectively. Those aged 15-18 years had the lowest whole nut consumption, but had the highest nut butter consumption. The consumption of total nuts was positively associated with education and socio-economic status, while whole nut consumption was inversely associated with BMI. In conclusion, the low percentage of nut consumers is of concern and new strategies to increase nut consumption are required. Future public health initiatives should be mindful of these patterns and predictors. In particular, different forms of nuts may appeal to different age and socio-economic groups.


Asunto(s)
Dieta , Conducta Alimentaria , Nueces , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Escolaridad , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda , Clase Social , Adulto Joven
8.
J Nutr ; 143(8): 1254-62, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23761651

RESUMEN

Regular nut consumption may improve markers of inflammation and endothelial dysfunction. The quantity of nuts required to achieve these health benefits without compromising body weight and acceptance is unknown. This study compared the effects of incorporating hazelnuts at 2 different doses with a diet without nuts on inflammatory markers, cell adhesion molecules, and body composition in 107 overweight and obese individuals. This was a randomized, controlled, parallel 12-wk intervention including 3 treatment arms: no nuts (control group), 30 g/d of hazelnuts, or 60 g/d of hazelnuts. Blood pressure, body composition, plasma high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6), intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), lipid, and apolipoprotein (apo) profiles were assessed at baseline and at 6 and 12 wk. "Desire" and "liking" for nuts were assessed during the intervention. Results showed no significant differences in follow-up clinical outcomes between groups after adjusting for baseline values, age, sex, and BMI (all P ≥ 0.10), except for a tendency toward improvement in VCAM-1 concentration in the 60-g/d nut group (P = 0.07). Hazelnut consumption significantly improved diet quality in a dose-response manner. Desire and liking for nuts remained stable in the 30-g/d group, whereas these ratings decreased significantly over time in the 60-g/d group (both P < 0.001). In conclusion, 12 wk of hazelnut consumption appears to have minimal effect on inflammatory markers and cell adhesion molecules in this group of healthy, normocholesterolemic overweight and obese individuals. Nut consumption improves diet quality without adversely affecting body composition. Consuming 30 g/d of nuts regularly is achievable, whereas 60 g/d appears to compromise desire and liking.


Asunto(s)
Biomarcadores/sangre , Composición Corporal , Dieta , Nueces , Obesidad/sangre , Sobrepeso/sangre , Adolescente , Adulto , Apolipoproteínas/sangre , Presión Sanguínea , Índice de Masa Corporal , Peso Corporal , Proteína C-Reactiva/análisis , Corylus , Femenino , Estudios de Seguimiento , Humanos , Inflamación/sangre , Inflamación/dietoterapia , Molécula 1 de Adhesión Intercelular/sangre , Interleucina-6/sangre , Lípidos/sangre , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Obesidad/dietoterapia , Sobrepeso/dietoterapia , Molécula 1 de Adhesión Celular Vascular/sangre , Adulto Joven
9.
medRxiv ; 2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36778355

RESUMEN

Background: In this review, we provide an updated assessment of available evidence on the pharmacokinetics (PK) of cannabidiol (CBD) and explore the impact of different factors on PK outcomes. Materials and Methods: This systematic review and meta-regression analysis was pre-registered (PROSPERO: CRD42021269857). We systematically searched Medline, Embase, PsychInfo, and Web of Science Core Collection up to November 19, 2022. Trials of CBD in healthy adults were included if they reported at least one of the PK parameters of interest, including Tmax, Cmax, AUC0-t, AUC0-inf, and T 1/2 , in serum or plasma. Studies of patient populations or CBD co-administration with other medications were excluded. The National Heart, Lung, and Blood Institute's Quality Assessment Tool for Before-After Studies with no Control Group was used. Random-effects multivariable meta-regression analysis was conducted. Results: A total of 112 trial arms from 39 studies were included; 26 trial arms had a "Good" quality, 70 "Fair," and 16 "Poor." Eight arms used inhalation CBD, 29 oromucosal, 73 oral, and 2 intravenous. CBD formulations could be categorized to nanotech (n=14), oil-based (n=21), alcohol-based (n=10), water-based (n=12), Sativex (n=17), and Epidiolex (n=22). For single-dose studies, CBD doses ranged between 2-100mg in inhalation, 5-50mg in oromucosal, and 0.42-6000mg in oral administration. Sixty-six trial arms had only male participants or a higher number of males than females. The duration of the PK session was between 4h-164h. A higher CBD dose was associated with higher Cmax, AUC0-t, and AUC0-inf. Compared to oral administration, oromucosal administration was associated with lower Cmax, AUC0-t, and AUC0-inf. Fed status was associated with higher Cmax and AUC0-t when compared to the fasting status. A higher ratio of female participants was associated with lower Tmax in oral administration and higher Cmax. Conclusion: As expected, CBD dose, route of administration, and diet were major determinants of CBD pharmacokinetics with oral routes providing higher bioavailability and nanotechnology formulations a faster onset. Though CBD appeared to have a faster onset and longer duration in females, more studies are required to delineate the role of biological sex. Factors that influence CBD PK have implications for medication development and appropriate dosing in clinical practice.

10.
Artículo en Inglés | MEDLINE | ID: mdl-37643301

RESUMEN

Background: In this review, we provide an updated assessment of available evidence on the pharmacokinetics (PK) of CBD and explore the impact of different factors on PK outcomes. Materials and Methods: This systematic review and meta-regression analysis was preregistered (PROSPERO: CRD42021269857). We systematically searched Medline, Embase, PsycInfo, and Web of Science Core Collection up to November 19, 2022. Trials of CBD in healthy adults were included if they reported at least one of the PK parameters of interest, including Tmax, Cmax, AUC0-t, AUC0-inf, and T1/2, in serum or plasma. Studies of patient populations or CBD co-administration with other medications were excluded. The National Heart, Lung, and Blood Institute's Quality Assessment Tool for Before-After Studies with no Control Group was used. Random-effects multivariable meta-regression analysis was conducted. Results: A total of 112 trial arms from 39 studies were included; 26 trial arms had a "Good" quality, 70 "Fair," and 16 "Poor." Eight arms used inhalation CBD, 29 oromucosal, 73 oral, and 2 intravenous. CBD formulations could be categorized to nanotech (n=14), oil-based (n=21), alcohol-based (n=10), water-based (n=12), Sativex (n=17), and Epidiolex® (n=22). For single-dose studies, CBD doses ranged between 2 and 100 mg in inhalation, 5-50 mg in oromucosal, and 0.42-6000 mg in oral administration. Sixty-six trial arms had only male participants or a higher number of male than female participants. The duration of the PK session was between 4 and 164 h. A higher CBD dose was associated with higher Cmax, AUC0-t, and AUC0-inf. Compared with oral administration, oromucosal administration was associated with lower Cmax, AUC0-t, and AUC0-inf. Fed status was associated with higher Cmax and AUC0-t when compared with the fasting status. A higher ratio of female participants was associated with lower Tmax in oral administration and higher Cmax. Conclusion: As expected, CBD dose, route of administration, and diet were major determinants of CBD PK with oral routes providing higher bioavailability and nanotechnology formulations a faster onset. Although CBD appeared to have a faster onset and longer duration in women, more studies are required to delineate the role of biological sex. Factors that influence CBD PK have implications for medication development and appropriate dosing in clinical practice.

11.
Psychopharmacology (Berl) ; 237(3): 787-800, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31811350

RESUMEN

RATIONAL: Caloric restriction increases the risk of relapse in abstinent drug users. Hormones involved in the regulation of energy balance and food intake, such as leptin and ghrelin, are implicated in drug-related behaviors. OBJECTIVES: We investigated the role of leptin and ghrelin in the augmentation of heroin seeking induced by chronic food restriction. METHODS: Rats self-administered heroin (0.1 mg/kg/infusion) for 10 days followed by 14 days of drug withdrawal. During withdrawal, rats were food restricted to 90% of their original body weight or were given free access to food. In experiment 1, we measured the plasma concentrations of leptin and ghrelin following heroin self-administration and withdrawal. In experiment 2, leptin was administered centrally (2.0 or 4.0 µg; i.c.v.) prior to a heroin-seeking test under extinction conditions. High density of both leptin and ghrelin receptors was previously identified in the ventral tegmental area (VTA), suggesting a direct effect on reward and motivation. Hence, we administered leptin (experiment 3; 0.125 or 0.250 µg/side), or ghrelin receptor antagonist JMV 2959 (experiment 4; 2.0 or 10.0 µg/side) directly into the VTA prior to the heroin-seeking test. RESULTS: Chronic food restriction significantly decreased plasma levels of leptin and elevated plasma levels of ghrelin. Central administration of leptin had no statistically significant effect on heroin seeking. Intra-VTA administration of either leptin or JMV 2959 dose-dependently and selectively decreased heroin seeking in the food-restricted rats. CONCLUSIONS: Leptin and ghrelin transmission in the VTA can modulate the augmentation of heroin seeking induced by chronic food restriction.


Asunto(s)
Comportamiento de Búsqueda de Drogas/fisiología , Privación de Alimentos/fisiología , Ghrelina/sangre , Dependencia de Heroína/sangre , Heroína/administración & dosificación , Leptina/sangre , Animales , Condicionamiento Operante/efectos de los fármacos , Condicionamiento Operante/fisiología , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Dependencia de Heroína/psicología , Masculino , Motivación/efectos de los fármacos , Motivación/fisiología , Ratas , Ratas Long-Evans , Autoadministración , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/metabolismo
12.
Food Chem ; 319: 126529, 2020 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-32199146

RESUMEN

Claims in the lay literature suggest soaking nuts enhances mineral bioavailability. Research on legumes and grains indicate soaking reduces phytate levels, however, there is no evidence to support or refute these claims for nuts. We assessed the effects of different soaking regimes on phytate and mineral concentrations of whole and chopped almonds, hazelnuts, peanuts, and walnuts. The treatments were: 1. Raw; 2. soaked for 12 h in salt solution; 3. soaked for 4 h in salt solution; 4. soaked for 12 h in water. Phytate concentrations were analysed using high-performance liquid chromatography (HPLC) and minerals by inductively coupled plasma mass spectrometry (ICP-MS). Differences in phytate concentrations between treated and untreated nuts were small, ranging from -12% to +10%. Overall, soaking resulted in lower mineral concentrations, especially for chopped nuts, and did not improve phytate:mineral molar ratios. This research does not support claims that 'activating' nuts results in greater nutrient bioavailability.


Asunto(s)
Arachis/química , Nueces/química , Rosanae/química , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Nutrientes/química , Valor Nutritivo , Ácido Fítico/química
13.
CMAJ ; 180(10): E39-46, 2009 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-19433812

RESUMEN

BACKGROUND: Weight regain often occurs after weight loss in overweight individuals. We aimed to compare the effectiveness of 2 support programs and 2 diets of different macronutrient compositions intended to facilitate long-term weight maintenance. METHODS: Using a 2 x 2 factorial design, we randomly assigned 200 women who had lost 5% or more of their initial body weight to an intensive support program (implemented by nutrition and activity specialists) or to an inexpensive nurse-led program (involving "weigh-ins" and encouragement) that included advice about high-carbohydrate diets or relatively high-monounsaturated-fat diets. RESULTS: In total, 174 (87%) participants were followed-up for 2 years. The average weight loss (about 2 kg) did not differ between those in the support programs (0.1 kg, 95% confidence interval [CI] -1.8 to 1.9, p = 0.95) or diets (0.7 kg, 95% CI -1.1 to 2.4, p = 0.46). Total and low-density lipoprotein (LDL) cholesterol levels were significantly higher among those on the high-monounsaturated-fat diet (total cholesterol: 0.17 mmol/L, 95% CI 0.01 to 0.33; p = 0.040; LDL cholesterol: 0.16 mmol/L, 95% CI 0.01 to 0.31; p = 0.039) than among those on the high-carbohydrate diet. Those on the high-monounsaturated-fat diet also had significantly higher intakes of total fat (5% total energy, 95% CI 3% to 6%, p < 0.001) and saturated fat (2% total energy, 95% CI 1% to 2%, p < 0.001). All of the other clinical and laboratory measures were similar among those in the support programs and diets. INTERPRETATION: A relatively inexpensive program involving nurse support is as effective as a more resource-intensive program for weight maintenance over a 2-year period. Diets of different macronutrient composition produced comparable beneficial effects in terms of weight loss maintenance.


Asunto(s)
Consejo Dirigido , Ejercicio Físico , Sobrepeso/dietoterapia , Sobrepeso/prevención & control , Adulto , Anciano , Índice de Masa Corporal , Carbohidratos de la Dieta , Grasas Insaturadas en la Dieta , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Educación del Paciente como Asunto , Resultado del Tratamiento , Aumento de Peso
14.
Am J Clin Nutr ; 87(2): 379-84, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18258628

RESUMEN

BACKGROUND: Brazil nuts provide a rich natural source of selenium, yet no studies have investigated the bioavailability of selenium in humans. OBJECTIVE: We investigated the efficacy of Brazil nuts in increasing selenium status in comparison with selenomethionine. DESIGN: A randomized controlled trial was conducted with 59 New Zealand adults. Participants consumed 2 Brazil nuts thought to provide approximately 100 mug Se, 100 mug Se as selenomethionine, or placebo daily for 12 wk. Actual intake from nuts averaged 53 mug Se/d (possible range: 20-84 mug Se). Plasma selenium and plasma and whole blood glutathione peroxidase (GPx) activities were measured at baseline and at 2, 4, 8, and 12 wk, and effects of treatments were compared. RESULTS: Plasma selenium increased by 64.2%, 61.0%, and 7.6%; plasma GPx by 8.3%, 3.4%, and -1.2%; and whole blood GPx by 13.2%, 5.3%, and 1.9% in the Brazil nut, selenomethionine, and placebo groups, respectively. Change over time at 12 wk in plasma selenium (P < 0.0001 for both groups) and plasma GPx activity in the Brazil nut (P < 0.001) and selenomethionine (P = 0.014) groups differed significantly from the placebo group but not from each other. The change in whole blood GPx activity was greater in the Brazil nut group than in the placebo (P = 0.002) and selenomethionine (P = 0.032) groups. CONCLUSION: Consumption of 2 Brazil nuts daily is as effective for increasing selenium status and enhancing GPx activity as 100 mug Se as selenomethionine. Inclusion of this high-selenium food in the diet could avoid the need for fortification or supplements to improve the selenium status of New Zealanders.


Asunto(s)
Bertholletia , Conducta Alimentaria , Glutatión Peroxidasa/sangre , Selenio/sangre , Selenometionina/administración & dosificación , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda , Factores de Tiempo
15.
World J Gastroenterol ; 23(25): 4632-4643, 2017 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-28740352

RESUMEN

AIM: To investigate the long-term effect of dietary education on a low fermentable oligosaccharide, disaccharide and polyol (FODMAP) diet on irritable bowel syndrome (IBS) symptoms and quality of life (QoL). METHODS: Participants with IBS (Rome III) were randomized to two groups. Group I commenced a low FODMAP diet at baseline. At three months, group II, so far a comparator group, crossed over to a low FODMAP diet while group I started re-challenging foods. All patients completed the IBS SSS (IBS symptom severity scoring system, 0-500 points increasing with severity), IBS QoL questionnaire (0-100 increasing with QoL), a FODMAP specific food frequency questionnaire and provided a stool sample at baseline, three and six months for microbiome analysis. RESULTS: Fifty participants were enrolled into group I (n = 23) or group II (n = 27). Participants in both groups were similar in baseline values but with more men in group I. There was a significantly lower IBS SSS (275.6 ± 63.6 to 128.8 ± 82.5 vs 246.8 ± 71.1 to 203.6 ± 70.1) (P < 0.0002) and increased QoL (68.5 ± 18.0 to 83 ± 13.4 vs 72.9 ± 12.8 to 73.3 ± 14.4) (P < 0.0001) in group I vs group II at 3 mo. The reduced IBS SSS was sustained at 6 mo in group I (160 ± 102) and replicated in group II (124 ± 76). Fiber intake decreased on the low FODMAP diet (33 ± 17 g/d to 21 ± 8 g/d) (P < 0.01) and after re-introducing FODMAP containing foods increased again to 27 ± 9 g/d. There was no change seen in the intestinal microbiome when participants adopted a low FODMAP diet. CONCLUSION: This study demonstrated that a reduction in FODMAPs improves symptoms in IBS and this improvement can be maintained while reintroducing FODMAPs.


Asunto(s)
Dieta Baja en Carbohidratos/métodos , Disacáridos/efectos adversos , Microbioma Gastrointestinal , Síndrome del Colon Irritable/dietoterapia , Calidad de Vida , Alcoholes del Azúcar/efectos adversos , Adulto , Colon/metabolismo , Colon/microbiología , Disacáridos/metabolismo , Femenino , Fermentación , Humanos , Síndrome del Colon Irritable/microbiología , Masculino , Persona de Mediana Edad , Educación del Paciente como Asunto , Índice de Severidad de la Enfermedad , Alcoholes del Azúcar/metabolismo , Encuestas y Cuestionarios
16.
Nutrients ; 9(11)2017 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-29113145

RESUMEN

Regular nut consumption is associated with reduced risk factors for chronic disease; however, most population-based studies lack consideration of effect modification by dietary pattern. The UK Women's Cohort Study (UKWCS) provides an ideal opportunity to examine relationships between nut consumption and chronic disease risk factors in a large sample with diverse dietary patterns. Nut and nutrient intake from 34,831 women was estimated using a food frequency questionnaire among self-identified omnivores, vegetarians and vegans. In this cross-sectional analysis, higher nut consumption was associated with lower body weight (difference between highest and lowest consumption categories from adjusted model: 6.1 kg; 95% CI: 4.7, 7.6) body mass index (BMI, 2.4 units difference; 95% CI: 1.9, 2.9), and waist circumference (2.6 cm difference; 95% CI: 1.4, 3.8) (all p for linear trend < 0.001). Higher nut consumption was also associated with reduced prevalence of high cholesterol and high blood pressure; having a history of heart attack, diabetes and gallstones; and markers of diet quality (all adjusted p for linear trend ≤ 0.011). Higher nut consumption appeared overall to be associated with greater benefits amongst omnivores compared to vegetarians and vegans. Findings support existing literature around beneficial effects of nut consumption and suggest that benefits may be larger among omnivores. Nut promotion strategies may have the highest population impact by specifically targeting this group.


Asunto(s)
Dieta Vegana , Dieta Vegetariana , Nueces , Veganos , Vegetarianos , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad
17.
Nutrients ; 9(3)2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28257045

RESUMEN

Despite their nutritional value, population-level nut consumption remains low. Studies suggest that individuals would eat more nuts on their doctor's advice, making health professionals potentially important for promoting nut consumption. This cross-sectional study aimed to examine the perceptions and knowledge of nuts and the predictors of nut promotion among health professionals in New Zealand. Dietitians, general practitioners (GPs), and practice nurses were identified from the Electoral Roll and invited to complete a questionnaire (n = 318, 292, and 149 respondents respectively). Over one-fifth of GPs and practice nurses believed that eating nuts could increase blood cholesterol concentrations and cause weight gain. The most common perceptions overall were that nuts are healthy; high in protein, fat, and calories; and are satiating. Nut consumption was recommended for reasons relating to these perceptions and because of nuts' selenium content. Conversely, reasons for suggesting the consumption of fewer nuts included that they were high in calories and fat, would cause weight gain, and concerns regarding allergies and cost. All groups of health professionals were more likely to promote nut consumption if they perceived nuts to reduce the risk of diabetes (all p ≤ 0.034). Education could improve health professionals' knowledge regarding the effects of nut consumption on blood cholesterol and body weight, alongside other health benefits, which should improve the advice given to patients and may thereby increase nut consumption.


Asunto(s)
Dieta Saludable , Medicina Basada en la Evidencia , Alimentos Funcionales/análisis , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud/educación , Promoción de la Salud , Nueces/química , Adulto , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etnología , Enfermedades Cardiovasculares/prevención & control , Estudios Transversales , Dieta Saludable/etnología , Femenino , Alimentos Funcionales/efectos adversos , Conocimientos, Actitudes y Práctica en Salud/etnología , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Valor Nutritivo , Nueces/efectos adversos , Educación del Paciente como Asunto , Riesgo , Respuesta de Saciedad , Autoinforme , Recursos Humanos
18.
Nutr Rev ; 74(4): 267-80, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26946252

RESUMEN

Coconut oil is being heavily promoted as a healthy oil, with benefits that include support of heart health. To assess the merits of this claim, the literature on the effect of coconut consumption on cardiovascular risk factors and outcomes in humans was reviewed. Twenty-one research papers were identified for inclusion in the review: 8 clinical trials and 13 observational studies. The majority examined the effect of coconut oil or coconut products on serum lipid profiles. Coconut oil generally raised total and low-density lipoprotein cholesterol to a greater extent than cis unsaturated plant oils, but to a lesser extent than butter. The effect of coconut consumption on the ratio of total cholesterol to high-density lipoprotein cholesterol was often not examined. Observational evidence suggests that consumption of coconut flesh or squeezed coconut in the context of traditional dietary patterns does not lead to adverse cardiovascular outcomes. However, due to large differences in dietary and lifestyle patterns, these findings cannot be applied to a typical Western diet. Overall, the weight of the evidence from intervention studies to date suggests that replacing coconut oil with cis unsaturated fats would alter blood lipid profiles in a manner consistent with a reduction in risk factors for cardiovascular disease.


Asunto(s)
Enfermedades Cardiovasculares/sangre , Colesterol/sangre , Cocos/química , Grasas de la Dieta/farmacología , Aceites de Plantas/farmacología , Enfermedades Cardiovasculares/etiología , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Aceite de Coco , Dieta , Grasas de la Dieta/efectos adversos , Humanos , Aceites de Plantas/efectos adversos
19.
Nutrients ; 7(9): 7523-42, 2015 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-26371037

RESUMEN

Nut consumption has been associated with improvements in risk factors for chronic disease in populations within North America, Europe and Iran. This relationship has not been investigated in New Zealand (NZ). The associations between nut consumption and cardiometabolic risk factors among New Zealanders were examined. Data from the 24-h diet recalls of 4721 participants from the NZ Adult Nutrition Survey 2008/2009 (2008/2009 NZANS) were used to determine whole and total nut intake. Anthropometric data and blood pressure were collected, as well as blood samples analysed for total cholesterol (total-C) and HDL cholesterol (HDL-C), glycated haemoglobin (HbA1c), C-reactive protein (CRP) and folate. Participants were classified according to their five-year cardiovascular disease (CVD) risk. Both whole and total nut consumers had significantly lower weight, body mass index (BMI), waist circumference and central adiposity than non-nut consumers (all p ≤ 0.044). Whole blood, serum and red blood cell folate concentrations were significantly higher among whole nut consumers compared to non-whole nut consumers (all p ≤ 0.014), with only serum folate higher in total nut consumers compared to non-total nut consumers (p = 0.023). There were no significant differences for blood pressure, total-C, HDL-C and HbA1c; however, significant negative associations between total nut consumption and CVD risk category (p < 0.001) and CRP (p = 0.045) were apparent. Nut consumption was associated with more favourable body composition and a number of risk factors, which could collectively reduce chronic disease.


Asunto(s)
Enfermedades Cardiovasculares/prevención & control , Dieta , Conducta Alimentaria , Nueces , Adolescente , Adulto , Anciano , Composición Corporal , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/fisiopatología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Encuestas Nutricionales , Factores Protectores , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios , Factores de Tiempo , Adulto Joven
20.
Am J Clin Nutr ; 76(4): 758-65, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12324288

RESUMEN

BACKGROUND: The association between vascular disease and elevated plasma total homocysteine (tHcy) concentrations is caused, in part, by inadequate intakes of dietary folate. Increasing folate intake either through supplements or foods naturally rich in folates has been shown to decrease tHcy concentrations. OBJECTIVE: The aim of this study was to determine whether a similar reduction in tHcy was possible in free-living persons receiving dietary counseling. DESIGN: The study included a 4-wk placebo-controlled dietary intervention trial in which participants consumed either unfortified breakfast cereal (control group) or an extra 350 micro g folate derived from food/d (dietary group). Serum folate and tHcy concentrations in both groups were measured before and after the intervention period, and the concentrations in the dietary group were also measured 17 wk after the intervention period. RESULTS: During the 4-wk intervention, mean dietary folate intake in the dietary group increased from 263 (95% CI: 225, 307) to 618 micro g/d (535, 714), resulting in a mean increase in serum folate of 37% (15%, 63%) and a decrease in tHcy from 12.0 (10.9, 13.3) to 11.3 micro mol/L (10.2, 12.5). A further decrease in tHcy occurred in the dietary group during follow-up, with a final tHcy concentration of 9.7 micro mol/L (8.8, 10.8). CONCLUSIONS: Increasing natural folate intake improved folate status and decreased tHcy concentrations to an extent that may significantly reduce the risk of vascular disease. Dietary modification may have advantages over folic acid fortification because the altered food-consumption patterns lead to increased intakes of several vitamins and minerals and decreased intakes of saturated fatty acids.


Asunto(s)
Consejo , Dieta , Ácido Fólico/administración & dosificación , Ácido Fólico/sangre , Homocisteína/sangre , Anciano , Grano Comestible , Ingestión de Energía , Femenino , Frutas , Humanos , Masculino , Persona de Mediana Edad , Nueva Zelanda , Nueces , Placebos , Semillas , Verduras
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