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1.
Elife ; 122024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976495

RESUMO

Mammals have evolved sex-specific adaptations to reduce energy usage in times of food scarcity. These adaptations are well described for peripheral tissue, though much less is known about how the energy-expensive brain adapts to food restriction, and how such adaptations differ across the sexes. Here, we examined how food restriction impacts energy usage and function in the primary visual cortex (V1) of adult male and female mice. Molecular analysis and RNA sequencing in V1 revealed that in males, but not in females, food restriction significantly modulated canonical, energy-regulating pathways, including pathways associated waith AMP-activated protein kinase, peroxisome proliferator-activated receptor alpha, mammalian target of rapamycin, and oxidative phosphorylation. Moreover, we found that in contrast to males, food restriction in females did not significantly affect V1 ATP usage or visual coding precision (assessed by orientation selectivity). Decreased serum leptin is known to be necessary for triggering energy-saving changes in V1 during food restriction. Consistent with this, we found significantly decreased serum leptin in food-restricted males but no significant change in food-restricted females. Collectively, our findings demonstrate that cortical function and energy usage in female mice are more resilient to food restriction than in males. The neocortex, therefore, contributes to sex-specific, energy-saving adaptations in response to food restriction.


Assuntos
Metabolismo Energético , Neocórtex , Animais , Feminino , Masculino , Neocórtex/fisiologia , Neocórtex/metabolismo , Camundongos , Córtex Visual/fisiologia , Córtex Visual/metabolismo , Fatores Sexuais , Privação de Alimentos/fisiologia , Camundongos Endogâmicos C57BL , Caracteres Sexuais , Leptina/metabolismo , Leptina/sangue , Adaptação Fisiológica , Restrição Calórica
2.
Animal ; 18(6): 101181, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38843670

RESUMO

Spontaneous lipolysis results in the breakdown of milk fat by the lipoprotein lipase (EC: 3.1.1.34), an enzyme present in milk. Free fatty acids (FFAs) and by-products released in milk during lipolysis can alter both the organoleptic value of milk (off-flavors release) and technological properties of dairy products (decrease in creaming capabilities). Current climate change is having significant impacts on the feeding of grazing animals, with negative consequences on the availability and quality of grass. We and others have demonstrated that dietary restriction increases milk lipolysis in the cow species. However, no data about the impact of feed restriction on milk lipolysis is available in the ewe species. Thus, this paper aims to investigate the effect of feed restriction on milk characteristics with regard to lipolysis values in dairy ewes. Two groups of 24 multiparous Lacaune ewes in mid-lactation received a "non-restricted" control diet (100% of ad libitum DM intake) or a "restricted" (RESTR) diet (65% of ad libitum DM intake) according to a 2 × 2 crossover design. Milk gross composition together with lipolysis analyses were performed. Blood samples were also screened for metabolites or hormone concentrations. The RESTR treatment induced a decrease in milk production (- 21% compared with control treatment) and a modification of the metabolism of dairy ewes characterized by an increase in plasma non-esterified fatty acids (NEFAs), which represents the balance between adipose tissue mobilization and the use of NEFA by other tissues (+153%), cholesterol (+17%) and ß-hydroxybutyrate (+4 %) levels. As a result, a decrease in BW of dairy ewes was observed (-7%). Feed restriction also resulted in a decrease in milk lipolysis estimated by the milk FFA measured by the copper-soap method (-63 and -62%, respectively, for morning and evening milking) or by the reference Bureau of Dairy Industry method (-51 and -57%, respectively, for morning and evening milking). The decrease in milk spontaneous lipolysis under feed restriction was not associated with a decrease in lipoprotein lipase activity in ewes. These results will be completed with proteomic and lipidomic studies in milk samples to better understand mechanisms initiated in the ewe species specifically with regard to lipolysis in milk.


Assuntos
Ração Animal , Ácidos Graxos não Esterificados , Lactação , Lipólise , Leite , Animais , Leite/química , Leite/metabolismo , Feminino , Lactação/fisiologia , Ovinos/fisiologia , Ração Animal/análise , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Dieta/veterinária , Indústria de Laticínios , Estudos Cross-Over , Privação de Alimentos/fisiologia
3.
J Toxicol Sci ; 49(7): 321-335, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945843

RESUMO

To examine the effects of decreased food consumption on toxicological parameters in juvenile rats, rats on postnatal day 21 were fed 40%, 50% (only four weeks), and 60% less food, compared to that of controls for four or eight weeks, and clinical observations, measurement of body and organ weights, morphological differentiation analysis, clinical pathology, and macroscopic and microscopic examinations were conducted. The body weight decreased depending on the degree of food restriction (FR). Cleavage of the balano-preputial skinfold was delayed, and cell debris in the epididymal lumen was noted as a related finding after four-week FR. Vaginal opening was also delayed, and some histopathological findings, such as absence of corpus luteum in the ovary, mucinous degeneration in the vagina, and immature uterus, were noted after eight-week FR. Erythrocyte count increased after four-week FR, but slightly decreased in males only after eight-week FR, and decreased leukocyte and/or reticulocyte counts, accompanied by related histopathological findings were noted after four- and eight-week FR. In blood chemistry, the levels of total protein including globulin, glucose, triglyceride, and calcium decreased, and sodium and chloride increased after four- and eight-week FR. Increases in activities of aspartate transaminase and lactate dehydrogenase and total bilirubin levels were noted after four-week FR, which were attenuated after eight-week FR. The effects of FR seemed to be more remarkable after four weeks. In drug safety evaluation, findings caused by malnutrition should be considered in juvenile toxicity studies when decreased food consumption is observed.


Assuntos
Peso Corporal , Animais , Masculino , Feminino , Tamanho do Órgão , Ratos , Restrição Calórica/efeitos adversos , Fatores de Tempo , Privação de Alimentos/fisiologia , Ratos Sprague-Dawley , Ratos Wistar
4.
Trop Anim Health Prod ; 56(5): 189, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864934

RESUMO

The aim was to evaluate the quality of the sheep skin of different sex classes submitted to different levels of feed restriction. Sheep without defined racial pattern of different sex classes (15 non-castrated males, 15 castrated males and 15 females), with initial body weight of 18.1 ± 0.4 kg and mean age of 90 days were distributed in a factorial 3 × 3, with three sex classes and 3 levels of feed restriction (ad libitum intake and restricted intake at 70 and 80%), with 5 repetitions. After slaughter, the skins were collected for physical-mechanical tests. The effect of the sex classes x levels of dietary restriction interaction was observed for transverse thickness and longitudinal rupture elongation (p < 0.05). Animals fed ad libitum had greater longitudinal transverse thickness (p < 0.05). Animals fed ad libitum and 70% feed restriction showed greater transverse elongation at break (p < 0.05). As for the difference between sex classes in the transverse thickness variable for tearing strength, the interaction sex classes x levels of feed restriction for transverse thickness, longitudinal thickness, transverse tearing strength and longitudinal tearing strength occurred (p < 0.05). Feed restriction reduces the physical quality of the skin of sheep of different sex classes, and the use of castrated male sheep in positive energy balance is recommended to obtain leather with greater thickness, longitudinal rupture elongation and transverse tear strength.


Assuntos
Pele , Animais , Masculino , Feminino , Carneiro Doméstico/fisiologia , Carneiro Doméstico/crescimento & desenvolvimento , Fatores Sexuais , Privação de Alimentos/fisiologia , Ração Animal/análise , Ovinos/fisiologia , Ovinos/crescimento & desenvolvimento , Orquiectomia/veterinária
5.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38812469

RESUMO

Study objectives were to characterize the effects of citrulline (CIT) on physiological and intestinal morphology metrics during heat stress (HS) and feed restriction. Forty crossbred gilts (30 ±â€…2 kg body weight [BW]) were assigned to one of five treatments: (1) thermoneutral (TN) fed ad libitum (AL) with control (CON) supplement (TNAL; n = 8), (2) TN pair-fed (PF) with CON (PF-CON; n = 8), (3) TN PF with CIT (PF-CIT; n = 8), (4) HS AL with CON (HS-CON; n = 8), and (5) HS AL with CIT (HS-CIT; n = 8). During the period (P) 1 (7 d), pigs were in TN conditions (23.6 °C) and fed AL their respective supplemental treatments. During P2 (2.5 d), HS-CON and HS-CIT pigs were fed AL and exposed to cyclical HS (33.6 to 38.3 °C), while TNAL, PF-CON, and PF-CIT remained in TN and were fed either AL or PF to their HS counterparts. Citrulline (0.13 g/kg BW) was orally administered twice daily during P1 and P2. HS increased rectal temperature (Tr), skin temperature (Ts), and respiration rate (RR) relative to TN pigs (0.8 °C, 4.7 °C, and 47 breaths/min, respectively; P < 0.01). However, HS-CIT had decreased RR (7 breaths/min, P = 0.04) and a tendency for decreased Tr (0.1 °C, P = 0.07) relative to HS-CON pigs. During P2, HS pigs had decreased feed intake (22%; P < 0.01) and a tendency for decreased average daily gain (P = 0.08) relative to TNAL pigs, and by experimental design, PF pigs followed this same pattern. Circulating lipopolysaccharide-binding protein tended to be decreased (29%; P = 0.08) in PF relative to TNAL pigs and was increased (41%; P = 0.03) in HS compared to PF pigs. Jejunum villus height was decreased in PF relative to TNAL pigs (15%; P = 0.03); however, CIT supplementation improved this metric during feed restriction (16%; P = 0.10). Jejunum mucosal surface area decreased in PF (16%; P = 0.02) and tended to decrease in HS (11%; P = 0.10) compared to TNAL pigs. Ileum villus height and mucosal surface area decreased in HS compared to TNAL pigs (10 and 14%, respectively; P ≤ 0.04), but both parameters were rescued by CIT supplementation (P ≤ 0.08). Intestinal myeloperoxidase and goblet cell area remained similar among treatments and intestinal segments (P > 0.24). In summary, CIT supplementation slightly improved RR and Tr during HS. Feed restriction and HS differentially affected jejunum and ileum morphology and while CIT ameliorated some of these effects, the benefit appeared dependent on intestinal section and stressor type.


Heat stress (HS) negatively affects animal health and production efficiency and is a significant economic burden to global animal agriculture. Although the mechanisms responsible for reduced animal productivity during HS are complex and multifaceted, increasing evidence points to decreased intestinal barrier function as an important mediator of this response. Furthermore, HS causes a voluntary reduction in feed intake, and feed restriction independently induces gastrointestinal hyperpermeability. Loss of intestinal barrier integrity facilitates bacteria translocation across the epithelium into local and systemic circulation, thus initiating an immune response. Dietary citrulline has been shown to support gut health by improving intestinal barrier integrity and modulating intestinal inflammation. Therefore, the current study investigated the effects of citrulline supplementation on physiological and intestinal morphology parameters in heat-stressed and feed-restricted growing pigs. Herein, citrulline supplementation reduced respiration rate and rectal temperature in pigs exposed to the thermal load. Heat stress and feed restriction compromised small intestinal morphology, and while supplementing citrulline improved some of these parameters, the effects depended on the intestinal region and stressor type. Additional research is needed to evaluate the potential effects of citrulline supplementation on gut health during HS or nutrient restriction.


Assuntos
Ração Animal , Citrulina , Suplementos Nutricionais , Animais , Citrulina/farmacologia , Citrulina/administração & dosagem , Suplementos Nutricionais/análise , Feminino , Ração Animal/análise , Suínos/fisiologia , Dieta/veterinária , Privação de Alimentos , Temperatura Alta , Intestinos/efeitos dos fármacos , Intestinos/anatomia & histologia , Intestinos/fisiologia , Temperatura Corporal/efeitos dos fármacos , Resposta ao Choque Térmico/efeitos dos fármacos
6.
Physiol Behav ; 282: 114582, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38750805

RESUMO

Food restriction can have profound effects on various aspects of behavior, physiology, and morphology. Such effects might be amplified in animals that are highly active, given that physical activity can represent a substantial fraction of the total daily energy budget. More specifically, some effects of food restriction could be associated with intrinsic, genetically based differences in the propensity or ability to perform physical activity. To address this possibility, we studied the effects of food restriction in four replicate lines of High Runner (HR) mice that have been selectively bred for high levels of voluntary wheel running. We hypothesized that HR mice would respond differently than mice from four non-selected Control (C) lines. Healthy adult females from generation 65 were housed individually with wheels and provided access to food and water ad libitum for experimental days 1-19 (Phase 1), which allowed mice to attain a plateau in daily running distances. Ad libitum food intake of each mouse was measured on days 20-22 (Phase 2). After this, each mouse experienced a 20 % food restriction for 7 days (days 24-30; Phase 3), and then a 40 % food restriction for 7 additional days (days 31-37; Phase 4). Mice were weighed on experimental days 1, 8, 9, 15, 20, and 23-37 and wheel-running activity was recorded continuously, in 1-minute bins, during the entire experiment. Repeated-measures ANOVA of daily wheel-running distance during Phases 2-4 indicated that HR mice always ran much more than C, with values being 3.29-fold higher during the ad libitum feeding trial, 3.58-fold higher with -20 % food, and 3.06-fold higher with -40 % food. Seven days of food restriction at -20 % did not significantly reduce wheel-running distance of either HR (-5.8 %, P = 0.0773) or C mice (-13.3 %, P = 0.2122). With 40 % restriction, HR mice showed a further decrease in daily wheel-running distance (P = 0.0797 vs. values at 20 % restriction), whereas C mice did not (P = 0.4068 vs. values at 20 % restriction) and recovered to levels similar to those on ad libitum food (P = 0.3634). For HR mice, daily running distances averaged 11.4 % lower at -40 % food versus baseline values (P = 0.0086), whereas for C mice no statistical difference existed (-4.8 %, P = 0.7004). Repeated-measures ANOVA of body mass during Phases 2-4 indicated a highly significant effect of food restriction (P = 0.0001), but no significant effect of linetype (P = 0.1764) and no interaction (P = 0.8524). Both HR and C mice had a significant reduction in body mass only when food rations were reduced by 40 % relative to ad libitum feeding, and even then the reductions averaged only -0.60 g for HR mice (-2.6 %) and -0.49 g (-2.0 %) for C mice. Overall, our results indicate a surprising insensitivity of body mass to food restriction in both high-activity (HR) and ordinary (C) mice, and also insensitivity of wheel running in the C lines of mice, thus calling for studies of compensatory mechanisms that allow this insensitivity.


Assuntos
Peso Corporal , Ingestão de Alimentos , Atividade Motora , Corrida , Animais , Camundongos , Feminino , Peso Corporal/fisiologia , Peso Corporal/genética , Ingestão de Alimentos/fisiologia , Ingestão de Alimentos/genética , Atividade Motora/fisiologia , Corrida/fisiologia , Privação de Alimentos/fisiologia , Seleção Artificial , Análise de Variância
7.
Endocrinology ; 165(7)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38815068

RESUMO

The growth hormone secretagogue receptor (GHSR), primarily known as the receptor for the hunger hormone ghrelin, potently controls food intake, yet the specific Ghsr-expressing cells mediating the orexigenic effects of this receptor remain incompletely characterized. Since Ghsr is expressed in gamma-aminobutyric acid (GABA)-producing neurons, we sought to investigate whether the selective expression of Ghsr in a subset of GABA neurons is sufficient to mediate GHSR's effects on feeding. First, we crossed mice that express a tamoxifen-dependent Cre recombinase in the subset of GABA neurons that express glutamic acid decarboxylase 2 (Gad2) enzyme (Gad2-CreER mice) with reporter mice, and found that ghrelin mainly targets a subset of Gad2-expressing neurons located in the hypothalamic arcuate nucleus (ARH) and that is predominantly segregated from Agouti-related protein (AgRP)-expressing neurons. Analysis of various single-cell RNA-sequencing datasets further corroborated that the primary subset of cells coexpressing Gad2 and Ghsr in the mouse brain are non-AgRP ARH neurons. Next, we crossed Gad2-CreER mice with reactivable GHSR-deficient mice to generate mice expressing Ghsr only in Gad2-expressing neurons (Gad2-GHSR mice). We found that ghrelin treatment induced the expression of the marker of transcriptional activation c-Fos in the ARH of Gad2-GHSR mice, yet failed to induce food intake. In contrast, food deprivation-induced refeeding was higher in Gad2-GHSR mice than in GHSR-deficient mice and similar to wild-type mice, suggesting that ghrelin-independent roles of GHSR in a subset of GABA neurons is sufficient for eliciting full compensatory hyperphagia in mice.


Assuntos
Núcleo Arqueado do Hipotálamo , Privação de Alimentos , Neurônios GABAérgicos , Grelina , Glutamato Descarboxilase , Hiperfagia , Receptores de Grelina , Animais , Masculino , Camundongos , Neurônios GABAérgicos/metabolismo , Receptores de Grelina/genética , Receptores de Grelina/metabolismo , Hiperfagia/metabolismo , Grelina/metabolismo , Grelina/farmacologia , Núcleo Arqueado do Hipotálamo/metabolismo , Privação de Alimentos/fisiologia , Glutamato Descarboxilase/metabolismo , Glutamato Descarboxilase/genética , Camundongos Transgênicos , Proteína Relacionada com Agouti/metabolismo , Proteína Relacionada com Agouti/genética , Camundongos Endogâmicos C57BL
8.
Physiol Behav ; 283: 114596, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38815713

RESUMO

In addition to its sweet taste, glucose has potent and rapid postoral actions (appetition) that enhance its reward value. This has been demonstrated by the experience-induced preference for glucose over initially preferred nonnutritive sweetener solutions in 24-h choice tests. However, some sweetener solutions (e.g., 0.8% sucralose) have inhibitory postoral actions that may exaggerate glucose appetition whereas others (e.g., 0.1% sucralose + 0.1% saccharin, S+S) do not. Experiment 1 revealed that food-restricted (FR) male C57BL/6J mice displayed similar rapid glucose appetition effects (stimulation of glucose licking within minutes) and conditioned flavor preferences following 1-h experience with flavored 0.8% sucralose or 0.1% S+S and 8% glucose solutions. Thus, the inhibitory effects of 0.8% sucralose observed in 24-h tests were not apparent in 1-h tests. Experiment 2 evaluated the effects of food deprivation state and sweetener concentration on glucose appetition in female mice. Unlike FR mice tested with 0.1% S+S and 8% glucose, ad libitum (AL) fed mice displayed no stimulation of 8% glucose licking in the 1-h tests. A second ad libitum group (AL) tested with 0.2% S+S and 16% glucose solutions displayed stimulation of 16% glucose licking by the third 1-h test. Both AL groups, like the FR group, developed a preference for the glucose-paired flavor over the S+S paired flavor. Thus, food restriction promotes increased glucose licking but is not required for a conditioned preference. The FR male mice (Exp. 1) and FR female mice (Exp. 2) showed similar appetition responses (licking stimulation and flavor preference) to 8% glucose.


Assuntos
Privação de Alimentos , Glucose , Camundongos Endogâmicos C57BL , Caracteres Sexuais , Sacarose , Edulcorantes , Animais , Masculino , Feminino , Camundongos , Glucose/farmacologia , Privação de Alimentos/fisiologia , Edulcorantes/farmacologia , Edulcorantes/administração & dosagem , Sacarose/farmacologia , Sacarose/administração & dosagem , Sacarose/análogos & derivados , Preferências Alimentares/efeitos dos fármacos , Preferências Alimentares/fisiologia , Sacarina/farmacologia , Sacarina/administração & dosagem , Relação Dose-Resposta a Droga
9.
Vet Med Sci ; 10(3): e1466, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38695249

RESUMO

BACKGROUND: In this study, we investigated the effects of swimming activity and feed restriction on digestion and antioxidant enzyme activities in juvenile rainbow trout (average body weight of 26.54 ± 0.36 g). METHODS: The stomach, liver and kidney tissues were obtained from four distinct groups: the static water group (fish were kept in static water and fed to satiation), the feeding restricted group (fish were kept in static water with a 25% feed restriction), the swimming exercised group (fish were forced to swimming at a flow rate of 1 Body Length per second (BL/s)) and the swimming exercised-feed restricted group (subjected to swimming exercise at a 1 BL/s flow rate along with a 25% feed restriction). We determined the levels of glutathione, lipid peroxidation and the activities of catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase and lactate dehydrogenase, as well as the presence of reactive oxygen species in the tissues obtained from the fish. Additionally, the activities of pepsin, protease, lipase and arginase in these tissues were measured. RESULTS: Swimming activity and feed restriction showed different effects on the enzyme activities of the fish in the experimental groups. CONCLUSION: It can be concluded that proper nutrition and exercise positively influence the antioxidant system and enzyme activities in fish, reducing the formation of free radicals. This situation is likely to contribute to the fish's development.


Assuntos
Antioxidantes , Oncorhynchus mykiss , Natação , Animais , Oncorhynchus mykiss/fisiologia , Oncorhynchus mykiss/metabolismo , Natação/fisiologia , Antioxidantes/metabolismo , Aquicultura , Condicionamento Físico Animal/fisiologia , Privação de Alimentos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Digestão/fisiologia , Ração Animal/análise , Fígado/enzimologia , Fígado/metabolismo
10.
STAR Protoc ; 5(2): 102935, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38470908

RESUMO

Food-anticipatory nose poking is a unique food-seeking behavior driven by the food-entrainable oscillator. Here, we present a protocol to record a novel food-seeking nose poking behavior in mice under temporally restricted feeding followed by food deprivation using the open-source feeding experimentation device version 3 (FED3). We describe steps for setting up the FED3 and cage, training, and habituation. We then detail procedures for setting up the schedule for time-restricted feeding and food deprivation and for generating ethograms from FED3 data. For complete details on the use and execution of this protocol, please refer to Ehichioya et al.1.


Assuntos
Ritmo Circadiano , Comportamento Alimentar , Animais , Camundongos , Comportamento Alimentar/fisiologia , Ritmo Circadiano/fisiologia , Privação de Alimentos/fisiologia , Masculino , Comportamento Animal/fisiologia
11.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473950

RESUMO

Compensatory growth (CG) is a physiological response that accelerates growth following a period of nutrient limitation, with the potential to improve growth efficiency and meat quality in cattle. However, the underlying molecular mechanisms remain poorly understood. In this study, 60 Huaxi cattle were divided into one ad libitum feeding (ALF) group and two restricted feeding groups (75% restricted, RF75; 50% restricted, RF50) undergoing a short-term restriction period followed by evaluation of CG. Detailed comparisons of growth performance during the experimental period, as well as carcass and meat quality traits, were conducted, complemented by a comprehensive transcriptome analysis of the longissimus dorsi muscle using differential expression analysis, gene set enrichment analysis (GSEA), gene set variation analysis (GSVA), and weighted correlation network analysis (WGCNA). The results showed that irrespective of the restriction degree, the restricted animals exhibited CG, achieving final body weights comparable to the ALF group. Compensating animals showed differences in meat quality traits, such as pH, cooking loss, and fat content, compared to the ALF group. Transcriptomic analysis revealed 57 genes and 31 pathways differentially regulated during CG, covering immune response, acid-lipid metabolism, and protein synthesis. Notably, complement-coagulation-fibrinolytic system synergy was identified as potentially responsible for meat quality optimization in RF75. This study provides novel and valuable genetic insights into the regulatory mechanisms of CG in beef cattle.


Assuntos
Privação de Alimentos , Perfilação da Expressão Gênica , Bovinos , Animais , Privação de Alimentos/fisiologia , Carne , Culinária , Composição Corporal/fisiologia , Músculo Esquelético/fisiologia , Transcriptoma
12.
Artigo em Inglês | MEDLINE | ID: mdl-38531153

RESUMO

Environmental stresses play critical roles in the physiology of crustaceans. Food deprivation is an important environmental factor and a regular occurrence in both natural aquatic habitats and artificial ponds. However, the underlying physiological response mechanisms to starvation-caused stress in crustaceans are yet to be established. In the present study, the hepatopancreas tissue of Macrobrachium nipponense was transcriptome analyzed and examined for starvation effects on oxidative stress, DNA damage, autophagy, and apoptosis across four fasting stages (0 (control group), 7, 14, and 21 days). These results indicated that a ROS-mediated regulatory mechanism is critical to the entire fasting process. At the initial stage of starvation (fasting 0 d ~ 7 d), ROS concentration increased gradually, activating antioxidant enzymes to protect the cellular machinery from the detrimental effects of oxidative stress triggered by starvation-induced stress. ROS content production (hydrogen peroxide and superoxide anion) then rose continuously with prolonged starvation (fasting 7 d ~ 14 d), reaching peak levels and resulting in autophagy in hepatopancreas cells. During the final stages of starvation (fasting 14 d ~ 21 d), excessive ROS induced DNA damage and cell apoptosis. Furthermore, autophagolysosomes and apoptosis body were further identified with transmission electron microscopy. These findings lay a foundation for further scrutiny of the molecular mechanisms combating starvation-generated stress in M. nipponense and provide fishermen with the theoretical guidance for adopting fasting strategies in M. nipponense aquaculture.


Assuntos
Autofagia , Hepatopâncreas , Estresse Oxidativo , Palaemonidae , Animais , Palaemonidae/fisiologia , Palaemonidae/genética , Palaemonidae/metabolismo , Hepatopâncreas/metabolismo , Dano ao DNA , Apoptose , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Inanição , Privação de Alimentos , Transcriptoma
13.
Behav Processes ; 214: 104974, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38043720

RESUMO

Three experiments were conducted to investigate Conditioned Olfactory Preferences using orthonasal inhalation, which is a less explored perceptual pathway compared to retronasal inhalation. In these experiments, odors were impregnated onto plastic disks to prevent the subjects from consuming or tasting them. The reinforcers used were a sucrose solution (Caloric groups) and a saccharin solution (Non-Caloric groups). The influence of nutritional deprivation was analyzed, with unrestricted access to food throughout the procedure in Experiment 1, food restriction during the conditioning phase in Experiment 2, and limited access to food during the test phase in Experiment 3. The results revealed conditioned preferences using both sucrose and saccharin as reinforcers. Furthermore, dietary restriction reduced the conditioned preference induced by saccharin, but not the preference induced by sucrose. These findings are discussed in light of the potential differences between orthonasal and retronasal presentation of odors during conditioning.


Assuntos
Privação de Alimentos , Sacarina , Humanos , Sacarina/farmacologia , Olfato , Odorantes , Sacarose/farmacologia
14.
Gen Comp Endocrinol ; 346: 114404, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37940008

RESUMO

Growth hormone (Gh) regulates growth in part by stimulating the liver to synthesize and release insulin-like growth factor-1 (Igf1), which then promotes somatic growth. However, for fish experiencing food limitation, elevated blood Gh can occur even with low circulating Igf1 and slow growth, suggesting that nutritional stress can alter the sensitivity of liver Igf1 synthesis pathways to Gh. Here, we examined how recent feeding experience affected Gh regulation of liver Igf1 synthesis pathways in juvenile gopher rockfish (Sebastes carnatus) to illuminate mechanisms underlying the nutritional modulation of Igf1 production. Juvenile gopher rockfish were maintained under conditions of feeding or complete food deprivation (fasting) for 14 d and then treated with recombinant sea bream (Sparus aurata) Gh or saline control. Gh upregulated hepatic igf1 mRNA levels in fed fish but not in fasted fish. The liver of fasted rockfish also showed a lower relative abundance of gene transcripts encoding teleost Gh receptors 1 (ghr1) and 2 (ghr2), as well as reduced protein levels of phosphorylated janus tyrosine kinase 2 (pJak2) and signal transducer and activator of transcription 5 (pStat5), which function to induce igf1 gene transcription following Gh binding to Gh receptors. Relative hepatic mRNA levels for suppressors of cytokine signaling (Socs) genes socs2, socs3a, and socs3b were also lower in fasted rockfish. Socs2 can suppress Gh activation of Jak2/Stat5, and fasting-related variation in socs expression may reflect modulated inhibitory control of igf1 gene transcription. Fasted rockfish also had elevated liver mRNA abundances for lipolytic hormone-sensitive lipase 1 (hsl1) and Igf binding proteins igfbp1a, -1b and -3a, reduced liver mRNAs encoding igfbp2b and an Igfbp acid labile subunit-like (igfals) gene, and higher transcript abundances for Igf1 receptors igf1ra and igf1rb in skeletal muscle. Together, these findings suggest that food deprivation impacts liver Igf1 responsiveness to Gh via multiple mechanisms that include a downregulation of hepatic Gh receptors, modulation of the intracellular Jak2/Stat5 transduction pathway, and possible shifts in Socs-inhibitory control of igf1 gene transcription, while also demonstrating that these changes occur in concert with shifts in liver Igfbp expression and muscle Gh/Igf1 signaling pathway components.


Assuntos
Geômis , Hormônio do Crescimento Humano , Perciformes , Animais , Hormônio do Crescimento/metabolismo , Privação de Alimentos/fisiologia , Fator de Transcrição STAT5/metabolismo , Geômis/genética , Geômis/metabolismo , Fígado/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Hormônio do Crescimento Humano/metabolismo , Perciformes/metabolismo , Receptores da Somatotropina/genética , Receptores da Somatotropina/metabolismo , Peixes/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/genética , Músculo Esquelético/metabolismo , RNA Mensageiro/genética
15.
Washington, D.C.; OPAS; 2024.
em Português | PAHO-IRIS | ID: phr-59341

RESUMO

Os sistemas alimentares atuais falham em fornecer dietas saudáveis ​​para todas as pessoas. Ações nos sistemas de agricultura, alimentação, saúde e meio ambiente são necessárias para reduzir o custo de alimentos nutritivos e aumentar a acessibilidade de alimentos saudáveis. Se os sistemas alimentares forem transformados, eles podem se tornar uma poderosa força catalisadora para acabar com a fome, a insegurança alimentar e a desnutrição em todas as suas formas. Consequentemente, a OMS e a OPAS promovem a aplicação de um pacote de medidas relacionadas aos sistemas alimentares, que mudam as regras do jogo, se complementam e se concentram na melhoria da qualidade nutricional dos alimentos ao longo da vida. ambientes. Este briefing descreve cada uma dessas medidas e por que elas são importantes. Além disso, são apresentados estudos de caso de países e exemplos de compromissos SMART e soluções inovadoras para transformar os sistemas alimentares e fornecer dietas saudáveis ​​para todo


Assuntos
Política Nutricional , Privação de Alimentos , Dieta Saudável , Rotulagem de Alimentos
16.
Behav Brain Res ; 458: 114736, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-37923220

RESUMO

Food deprivation may cause neurological dysfunctions including memory impairment. The mollusk Aplysia is a suitable animal model to study prolonged food deprivation-induced memory deficits because it can sustain up to 14 days of food deprivation (14DFD). Sensitization of defensive withdrawal reflexes has been used to illustrate the detrimental effects of 14DFD on memory formation. Under normal feeding conditions (i.e., two days food deprivation, 2DFD), aversive stimuli lead to serotonin (5-HT) release into the hemolymph and neuropil, which mediates sensitization and its cellular correlates including increased excitability of tail sensory neurons (TSNs). Recent studies found that 14DFD prevents both short-term and long-term sensitization, as well as short-term increased excitability of TSNs induced by in vitro aversive training. This study investigated the role of 5-HT in the absence of sensitization and TSN increased excitability under 14DFD. Because 5-HT is synthesized from tryptophan obtained through diet, and its exogeneous application alone induces sensitization and increases TSN excitability, we hypothesized that 1) 5-HT level may be reduced by 14DFD and 2) 5-HT may still induce sensitization and TSN increased excitability in 14DFD animals. Results revealed that 14DFD significantly decreased hemolymph 5-HT level, which may contribute to the lack of sensitization and its cellular correlates, while ganglia 5-HT level was not changed. 5-HT exogenous application induced sensitization in 14DFD Aplysia, albeit smaller than that in 2DFD animals, suggesting that this treatment can only induce partial sensitization in food deprived animals. Under 14DFD, 5-HT increased TSN excitability indistinguishable from that observed under 2DFD. Taken together, these findings characterize 5-HT metabolic deficiency under 14DFD, which may be compensated, at least in part, by 5-HT exogenous application.


Assuntos
Aplysia , Serotonina , Animais , Serotonina/metabolismo , Aplysia/fisiologia , Privação de Alimentos , Neurônios Aferentes/fisiologia , Gânglios
17.
Nutrients ; 15(24)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38140367

RESUMO

Fasting is a nutritional practice involving complete food restriction for a varying length of time [...].


Assuntos
Disfunção Cognitiva , Jejum , Humanos , Privação de Alimentos , Disfunção Cognitiva/etiologia , Alimentos
18.
Bull Exp Biol Med ; 175(5): 608-611, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37861909

RESUMO

Trypsin is mainly regarded as a digestive enzyme, but there is evidence that activation of protease-activated receptor-2 (PAR-2) leads to behavioral changes. There are no data on trypsin activity in the serum of animals under conditions of thirst and starvation in the available literature. In our experiments, water deprivation led to a significant (p⩽0.05) increase in trypsin activity in rats, and food deprivation led to its decrease in comparison with controls (free access to water and food). After deprived rats received water and food, a decrease in trypsin activity was observed in both experimental groups. Changes in trypsin activity under conditions of water or food deprivation and after satiation were accompanied by shifts in some biochemical parameters of the bloods. Under conditions of metabolic stress (starvation and thirst), opposite changes in trypsin activity seem to indicate its participation in the mechanisms of adequate restructuring of metabolism and maintenance of vital processes in the body.


Assuntos
Privação de Alimentos , Água , Ratos , Animais , Tripsina/metabolismo , Peptídeo Hidrolases , Sede
19.
Zoolog Sci ; 40(5): 382-389, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37818887

RESUMO

In the pond snail Lymnaea stagnalis, serotonin (5-HT) plays an important role in feeding behavior and its associated learning (e.g., conditioned taste aversion: CTA). The 5-HT content in the central nervous system (CNS) fluctuates with changes in the nutritional status, but it is also expected to be influenced by changes in the serotonin transporter (SERT) expression level. In the present study, we identified SERT in Lymnaea and observed its localization in 5-HTergic neurons, including the cerebral giant cells (CGCs) in the cerebral ganglia and the pedal A cluster neurons and right and left pedal dorsal 1 neurons in the pedal ganglia by in situ hybridization. Real-time PCR revealed that the SERT mRNA expression level was lower under severe food deprivation than under mild food deprivation in the whole CNS as well as in a single CGC. These results inversely correlated with previous data that the 5-HT content in the CNS was higher in the severely food-deprived state than in the mildly food-deprived state. Furthermore, in single CGCs, we observed that the 5-HT level was significantly increased in the severely food-deprived state compared with the mildly food-deprived state. Our present findings suggest that changes in the SERT expression level associated with food deprivation may affect 5-HT signaling, probably contributing to learning and memory mechanisms in Lymnaea.


Assuntos
Privação de Alimentos , Lymnaea , Animais , Privação de Alimentos/fisiologia , Lymnaea/fisiologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Paladar , Serotonina , Aprendizagem da Esquiva/fisiologia
20.
J Dairy Sci ; 106(12): 9733-9744, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37641280

RESUMO

Choline requirements for dairy cattle are unknown. However, enhanced postruminal supply of choline may increase flux through the methionine cycle to spare Met for other functions such as protein synthesis and phosphatidylcholine (PC) synthesis during periods of negative nutrient balance (NNB). The objective was to investigate the effects of postruminal choline supply during a feed restriction-induced NNB on hepatic abundance and phosphorylation of mTOR (mechanistic target of rapamycin)-related signaling proteins, hepatic lipidome and plasma AA. Ten primiparous rumen-cannulated Holstein cows (158 ± 24 DIM) were used in a replicated 5 × 5 Latin square design with 4 d of treatment and 10 d of recovery (14 d/period). Treatments were unrestricted intake with abomasal infusion of water, restricted intake (R; 60% of net energy for lactation requirements to induce NNB) with abomasal infusion of water (R0) or restriction plus abomasal infusion of 6.25, 12.5, or 25 g/d choline ion. Liver tissue was collected via biopsy on d 5 after infusions ended and used for Western blot analysis to measure proteins involved in mTOR signaling and untargeted lipidomics. Blood was collected on d 1 to 5 for plasma AA analysis. Statistical contrasts for protein and AA data were A0 versus R0 (CONT1), R0 versus the average of choline dose (CONT2) and tests of linear and quadratic effects of choline dose. Analysis of lipidomic data were performed with the web-based metabolomic processing tool MetaboAnalyst 5.0. Ratios of p-RPS6KB1:tRPS6KB1, p-EEF2:tEEF2, and p-EIF2:tEIF2 were greater with R (CONT1). Among those, supply of choline led to decreases in p-EEF2:tEEF2 (CONT2), p-EIF2:tEIF2 and tended to decrease p-EIF4BP1:tEIF4BP1. However, the effect was quadratic only for p-EEF2:tEEF2 and p-EIF2A:tEIF2A, reaching a nadir at 6.25 to 12.5 g/d choline ion. The ratio of p-RPS6KB1:tRPS6KB1 was not affected by supply of choline and was close to 2-fold greater at 25 g/d choline versus A0. Plasma Met concentration decreased with R (CONT1), but increased linearly with choline. Restriction also increased plasma 3-methyl-histidine (CONT1). The partial least squares discriminant analysis model of liver lipids distinguished treatments, with 13.4% of lipids being modified by treatment. One-way ANOVA identified 109 lipids with a false discovery rate ≤0.05. The largest group identified was PC species; all 35 detected decreased with R versus A0, but there were few differences among choline treatments. Overall, data suggested that dephosphorylation of EEF2 and EIF2A due to enhanced choline supply potentially helped maintain or increase protein synthesis during NNB. While activation of mTOR was not altered by choline, this idea of increased protein synthesis is partly supported by the increased circulating Met. However, enhanced postruminal choline had limited effects on the species of lipid produced during a period of NNB.


Assuntos
Aminoácidos , Colina , Fígado , Colina/sangue , Colina/metabolismo , Fígado/metabolismo , Feminino , Animais , Bovinos , Transdução de Sinais , Aminoácidos/sangue , Aminoácidos/metabolismo , Lactação , Período Periparto/sangue , Período Periparto/metabolismo , Privação de Alimentos , Biópsia/veterinária , Lipídeos/sangue , Proteínas , Rúmen/metabolismo
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