Modification of the template capacity of liver chromatin for form-B ribonucleic acid polymerase by food intake in rats under controlled feeding schedules.
Ontology highlight
ABSTRACT:
SUBMITTER: Barbiroli B
PROVIDER: S-EPMC1165359 | biostudies-other | 1975 Mar
REPOSITORIES: biostudies-other
Similar Datasets
Project description:Assays of transcription in vitro, with Escherichia coli RNA polymerase or wheat-germ RNA polymerase II, were used to characterize chromatin templates isolated from the left Müllerian duct of the chick embryo during normal development, and during development in the presence of diethylstilboestrol. Control Müllerian-duct template capacity with E. coli RNA polymerase decreased from 6.42% on day 10 to 4.34% by day 15 of development. Similar results were found with wheat-germ RNA polymerase II. In the presence of rifampicin and heparin, the prokaryotic enzyme transcribed a number-average RNA chain of 670 nucleotide residues, at an average rate of 110 nucleotide residues/min, from Müllerian-duct chromatin of all developmental stages. From day 10 to day 15 there was a 44% decrease in the number of initiation sites for E. coli RNA polymerase on Müllerian-duct chromatin. A 47% decline was observed when these chromatins were transcribed with excess RNA polymerase II in the presence of rifamycin Af/013. Signs of increasing responsiveness to oestrogen developed between days 10 and 16. Embryos exposed to maximally responsive doses of diethylstilboestrol for 2 days showed increases in Müllerian-duct chromatin template capacity, RNA-chain initiation sites, wet weight, protein and RNA. The changes seen in the oviduct of the 1-week-old chick injected for 2 days with diethylstilboestrol were defined as 100% responses. By comparison, the Müllerian duct, after exposure to diethylstilboestrol from day 10 to day 12, from day 13 to day 15 or from day 16 to day 18, showed a 15%, 39% and 72% template response respectively, and a 42%, 56% and 85% initiation-site change respectively. A similar developmental trend was observed in all parameters. It is concluded that oestrogenic responsiveness in the developing Müllerian duct increases from day 10 to nearly maximal values by day 16 of development, and that this transition is paralleled by a progressive restriction of genomic activity.
| S-EPMC1161304 | biostudies-other
Project description:Energy-yielding beverages reportedly contribute to positive energy balance uniquely. They are highly consumed and evoke weaker satiety signaling and dietary energy compensation than solid foods of the same energy content. This study measured the contribution of learning to appetitive sensations and adjustments of energy intake for preloads varying in energy content and food form in lean and obese adults. One-hundred seven participants received four preload trials before and after a dietary intervention in this randomized cross-over trial with the stipulation that lean and obese individuals were evenly assigned to each intervention. The study entailed monitoring appetitive sensations and daily energy intake after consumption of low and high energy beverage and solid food loads on weekly visit days. Preload testing was conducted at baseline, followed by daily ingestion of one load for 14 days and then retesting responses to the four treatments. Lean individuals compensated precisely for the high energy beverage and solid loads from the onset of the study, whereas the obese did not alter eating patterns after consuming the higher energy beverage load. The learning intervention did not have an effect on the responses to the preloads, as responses in both lean and obese participants did not differ from baseline values. Responses to personality and eating behavior questionnaires revealed differences between the lean and obese groups and weakly, but significantly, predicted challenge meal and total daily energy intake. These data suggest that lean and obese individuals respond to energy in beverage form differently, and this is not altered by purposeful daily exposure to loads varying in physical form and energy content for two weeks.
| S-EPMC4184995 | biostudies-literature
Project description:In fish models, seasonal change in feeding is under the influence of water temperature. However, the effects of temperature on appetite control can vary among fish species and the mechanisms involved have not been fully characterized. Using goldfish (Carassius auratus) as a model, seasonal changes in feeding behavior and food intake were examined in cyprinid species. In our study, foraging activity and food consumption in goldfish were found to be reduced with positive correlation to the gradual drop in water temperature occurring during the transition from summer (28.4 ± 2.2°C) to winter (15.1 ± 2.6°C). In goldfish with a 4-week acclimation at 28°C, their foraging activity and food consumption were notably higher than their counterparts with similar acclimation at 15°C. When compared to the group at 28°C during summer, the attenuation in feeding responses at 15°C during the winter also occurred with parallel rises of leptin I and II mRNA levels in the liver. Meanwhile, a drop in orexin mRNA along with concurrent elevations of CCK, MCH, POMC, CART, and leptin receptor (LepR) transcript expression could be noted in brain areas involved in feeding control. In short-term study, goldfish acclimated at 28°C were exposed to 15°C for 24 h and the treatment was effective in reducing foraging activity and food intake. The opposite was true in reciprocal experiment with a rise in water temperature to 28°C for goldfish acclimated at 15°C. In parallel time-course study with lowering of water temperature from 28 to 15°C, short-term exposure (6-12 h) of goldfish to 15°C could also increase leptin I and II mRNA levels in the liver. Similar to our seasonality study, transcript level of orexin was reduced along with up-regulation of CCK, MCH, POMC, CART, and LepR gene expression in different brain areas. Our results, as a whole, suggest that temperature-driven regulation of leptin output from the liver in conjunction with parallel modulations of orexigenic/anorexigenic signals and leptin responsiveness in the brain may contribute to the seasonal changes of feeding behavior and food intake observed in goldfish.
| S-EPMC6416165 | biostudies-literature
Project description:BackgroundAlthough general parenting styles and restrictive parental feeding practices have been associated with children's weight status, few studies have examined the association between feeding styles and proximal outcomes such as children's food intake, especially in multi-ethnic families with limited incomes. The purpose of this study was to evaluate the association of parental feeding styles and young children's evening food intake in a multiethnic sample of families in Head Start.MethodsParticipants were 715 Head Start children and their parents from Texas and Alabama representing three ethnic groups: African-American (43%), Hispanic (29%), and White (28%). The Caregivers Feeding Styles Questionnaire (Hughes) was used to characterize authoritative, authoritarian (referent), indulgent or uninvolved feeding styles. Food intake in several food groups was calculated from 3 days of dietary recalls for the child for evening food intakes from 3 PM until bedtime.ResultsCompared to children of authoritarian parents, intakes of fruits, juice and vegetables were lowest among children of indulgent or uninvolved parents (1.77 +/- 0.09 vs 1.45 +/- 0.09 and 1.42 +/- 0.11 cups) as were intakes of dairy foods (0.84 +/- 0.05 vs 0.67 +/- 0.05 and 0.63+0.06 cups), respectively.ConclusionFindings suggest that permissive parent feeding styles like indulgent or uninvolved relate negatively to children's intake of nutrient-rich foods fruit, 100% fruit juice, vegetables and dairy foods from 3 PM until bedtime.
| S-EPMC2739505 | biostudies-literature
Project description:Galanin is a neuropeptide widely expressed in the brain. It is implicated in energy expenditure, feeding, and the regulation of body weight. Numerous studies have revealed that galanin regulates food intake via galanin receptors, 5-HT(1A) receptor and adrenergic α-2 receptor. In this review, we summarize recent findings that reveal the essential role of galanin in increasing food intake as well as body weight and that identify the individual galanin receptor subtypes involved in the brain's modulation of food intake and energy expenditure, to provide a theoretical basis for further studies of different aspects of galanin action.
| S-EPMC5560389 | biostudies-other
Project description:BackgroundTime-restricted feeding (TRF) is a dieting strategy based on nutrients availability and diurnal rhythm, shown to improve lipid metabolism efficiency. We have demonstrated previously that retinoic acid-related (RAR) orphan receptor (ROR) γ is the primary transcription factor controlling cholesterol (CHO) biosynthesis program of animals. However, the functional role of RORγ in liver physiology of pigs in response to TRF has not been determined, largely due to the lack of functional models and molecular tools. In the present study, we established porcine liver organoids and subjected them to restricted nutrients supply for 10-h during the light portion of the day.ResultsOur results showed that TRF regimen did not alter hepatocyte physiology, including unchanged cell viability, caspase 3/7 enzyme activity and the gene signature of cell proliferation in porcine liver organoids, compared to the control group (P > 0.05). Furthermore, we found that TRF downregulated the hepatic CHO biosynthesis program at both mRNA and protein levels, along with the reduced cellular CHO content in porcine liver organoids (P < 0.05). Using unbiased bioinformatic analysis of a previous ChIP-seq data and ChIP-qPCR validation, we revealed RORγ as the predominant transcription factor that responded to TRF, amongst the 12 targeted nuclear receptors (NRs) (P < 0.05). This was likely through RORγ direct binding to the MVK gene (encoding mevalonate kinase). Finally, we showed that RORγ agonists and overexpression enhanced the enrichment of co-factor p300, histone marks H3K27ac and H3K4me1/2, as well as RNA polymerase II (Pol-II) at the locus of MVK, in TRF-porcine liver organoids, compared to TRF-vector control (P < 0.05).ConclusionsOur findings demonstrate that TRF triggers the RORγ-mediated chromatin remodeling at the locus of CHO biosynthesis genes in porcine liver organoids and further improves lipid metabolism.
| S-EPMC7604961 | biostudies-literature
Project description:Reward-based eating drive is associated with individual consumption, but there has been a paucity of research on the relationships between parental reward-based eating, child feeding behaviors, and child food consumption. Child feeding behaviors likely to be associated with parental reward-based eating drive include the provision of ultra-processed foods, as they are designed to be hyperpalatable and are associated with disordered food intake. The present study uses a virtual reality (VR) buffet restaurant environment to examine parents' food choice behaviors for their children and a food frequency assessment to measure the children's reported consumption over the course of a week. Results found that parental reward-based eating drive significantly predicted ultra-processed calories chosen by parents for their children in the VR Buffet, as well as the amount of ultra-processed food children ate according to the food frequency assessment. Both of these effects were significantly mediated by the healthfulness of the home food environment. This study is among the first to demonstrate associations between parental reward-based eating drive and child-focused food behavior and to elucidate a mediating effect of the home food environment on such relationships. These findings may be useful for the development of family-based interventions to improve child feeding and ultimately child health.
| S-EPMC8529800 | biostudies-literature
Project description:The increasing prevalence of obesity and eating disorders makes identifying neural substrates controlling eating and regulating body weight a priority. Recent studies have highlighted the role of the lateral septum (LS) in eating control mechanisms. The current study explored the roles of gamma-aminobutyric acid (GABA) receptors within the LS in the control of food intake. Experiments with a rat model (n ≥ 11/group) showed that LS microinjection of the GABAA receptor agonist, muscimol, and the GABAB receptor agonist, baclofen hydrochloride (baclofen), elicited intense, dose-dependent feeding. In contrast, LS pretreatment with the GABAA receptor antagonist, picrotoxin, markedly reduced the muscimol-elicited feeding, and pretreatment injections with the GABAB receptor antagonist, 2-hydroxysaclofen (2-OH saclofen), reduced the baclofen evoked response. Next, we showed that picrotoxin injection at the beginning of the dark phase of the light-dark cycle-when rats show a burst of spontaneous eating-reduced naturally occurring feeding, whereas 2-OH saclofen was ineffective. These results indicate that the activation of LS GABAA and GABAB receptors strongly stimulates feeding and suggests potential roles in feeding control neurocircuitry. In particular, our evidence indicates that endogenous LS GABA and GABAA receptors may be involved in mediating naturally occurring nocturnal feeding.
| S-EPMC9312437 | biostudies-literature
Project description:Deviations in execution from the prescribed drug intake schedules (timing non adherence) are frequent and may pose a substantial risk for therapeutic failure. Simple methods to monitor timing adherence with multiple drugs are missing. A new technology, i.e., the polymedication electronic monitoring system (POEMS) attached to a multidrug punch card, was used in a clinical trial on outpatients with prescribed medicines for vascular risk reduction. The complete delineation of timing adherence allows for the calculation of objective adherence parameters and the linking of exposure with drug-drug interactions. A sub-analysis was performed on 68 patients, who were prescribed lipid lowering therapy. A smaller intake time variability of the lipid lowering drug was significantly associated with better levels of LDL-cholesterol, independently of the time of day. This finding may challenge current general recommendations for the timing of lipid lowering drugs' intake and substantiate that inter-individual differences in timing adherence may contribute to response variability. Thus, objective parameters based on multidrug adherence monitoring should be considered as independent variables in personalized medicine. In clinical practice, personalized intake recommendations according to patients' pattern of timing adherence may help to optimize the effectiveness of lipid lowering agents.
| S-EPMC4251372 | biostudies-literature
Project description:Growth hormone stimulates the synthesis of RNA in hypophysectomized rat liver. The question whether the hormonal stimulation of RNA synthesis is due to the activation of repressed cistrons or to other factors was studied. Nuclear RNA from the livers of adult female hypophysectomized and growth-hormone-treated rats was examined for molecular homology by hybridization techniques: no new species of RNA were detected after hormone treatment. The template activity of the chromatin for RNA synthesis is also not increased by the action of growth hormone. Short- and long-pulse-labelling experiments demonstrate that the hormonal stimulation of RNA synthesis is most marked in experiments where the period of incorporation of radioactive precursors is limited to 1-2hr. It is concluded that the hormone influences essentially the rate of RNA synthesis in these tissues.
| S-EPMC1187364 | biostudies-other