Project description:During the immediate postnatal period, the liver, with its role in energy metabolism and macromolecule synthesis, plays a central role in the perinatal transition. Using RNA microarrays and several complementary computational analyses, we characterized changes in hepatic gene expression in the rat across a developmental period starting with the late gestation fetus (embryonic day 21), and including 30 min postnatal (PN), 4 hr PN, 12 hr PN, 1 day PN and 1 week after birth. Following subtle changes in gene expression at the earliest postnatal time point, there were marked changes that occurred between 4 hr and 12 hr after birth. These reflected changes in multiple metabolic pathways, with expression of enzymes involved in glycolysis and cholesterol synthesis showing the greatest change. Over 50% of nuclear-encoded mitochondrial genes changed in the first 7 days of postnatal life, with 25% changing within the first 24 hr. We also observed changes coinciding with a transient period of synchronous hepatocyte proliferation that we had observed previously, which occurs during the first postnatal week. Analysis for upstream regulators of gene expression indicated multiple initiating factors, including cell stress, hormones and cytokines. Also implicated were multiple canonical transcription factor networks. We conclude that changes in gene expression during the early phases of the perinatal transition involve a complex, choreographed network of signaling pathways that respond to a variety of environmental stimuli. This transcriptomic response during the immediate postnatal period reflects a complex metabolic adaptive response that incorporates a panoply of signaling pathways and transcriptional regulators.
Project description:Aside from the perinatal complications associated with low birth weight, individuals born with intra-uterine growth restriction suffer from chronic diseases late in life that ultimately lead to a shortened lifespan. These late life metabolic sequelae of low birth weight include obesity and metabolic syndrome, diabetes mellitus, cardiovascular disease, hypertension, stroke, dyslipidemia, and non-alcoholic fatty liver disease/steatohepatitis. Animal models employing perinatal calorie restriction recapitulate the observations made in humans. Interestingly, if continued calorie restriction is employed post-natally the late life sequelae of intra-uterine growth restriction are ameliorated. These observations linking both fetal and early post natal growth to later health is now termed the developmental origins of health and disease. To further our understanding of the mechanism of how early growth affects late life health we have employed Affymetrix microarray-based expression profiling to characterize hepatic gene expression in a rat model of maternal semi-nutrient restriction. In these experiments we have limited maternal calorie intake to 50% of normal so as to create 3 groups of animals: Control (Con) male offspring born to mothers who were fed normally throughout gestation and lactation; intra-uterine calorie restricted male offspring (IUCR) born to mothers who had 50% restriction of calories from e11 to e21; and combined intra-uterine and post-natal calorie restriction (IPCR) male offspring who were born to mothers who received calorie restriction during both fetal growth (e11 to e21) and post-natally (p1-p21). Livers were collected at p21(day 21 of life) for Con and IPCR groups (IUCR withheld owing to ‘catch up” growth), and at p450 (day 450 of life) for Con, IUCR, and IPCR. The profiling data reveals clear alteration of circadian cycling at P21, and subtle changes for circadian gene expression at p450. In addition, a clear transcriptional response is found during active calorie restriction at p21 but an absence of a transcriptional response late in life at p450. Transcritional studies have been performed using Affymetrix Rat Gene 1.0 arrays for the following treatment groups, with each group run in triplicate (each replicate from separate littermates): Day 21 Control, Day 21 IPCR, Day 450 Con, Day 450 IUCR, Day 450 IPCR
Project description:During the immediate postnatal (PN) period, the liver, with its role in energy metabolism and macromolecule synthesis, plays a central role in the perinatal transition. Using RNA microarrays and several complementary computational analyses, we characterized changes in hepatic gene expression in the rat across a developmental period starting with the late gestation fetus (embryonic day 21), and including 30 min PN, 4 h PN, 12 h PN, 1 day PN, and 1 week after birth. Following subtle changes in gene expression at the earliest PN time point, there were marked changes that occurred between 4 and 12 h after birth. These reflected changes in multiple metabolic pathways, with expression of enzymes involved in glycolysis and cholesterol synthesis showing the greatest change. Over 50% of nuclear-encoded mitochondrial genes changed in the first 7 days of PN life, with 25% changing within the first 24 h. We also observed changes coinciding with a transient period of synchronous hepatocyte proliferation that we had observed previously, which occurs during the first PN week. Analysis for upstream regulators of gene expression indicated multiple initiating factors, including cell stress, hormones, and cytokines. Also implicated were multiple canonical transcription factor networks. We conclude that changes in gene expression during the early phases of the perinatal transition involve a complex, choreographed network of signaling pathways that respond to a variety of environmental stimuli. This transcriptomic response during the immediate PN period reflects a complex metabolic adaptive response that incorporates a panoply of signaling pathways and transcriptional regulators.
Project description:Aside from the perinatal complications associated with low birth weight, individuals born with intra-uterine growth restriction suffer from chronic diseases late in life that ultimately lead to a shortened lifespan. These late life metabolic sequelae of low birth weight include obesity and metabolic syndrome, diabetes mellitus, cardiovascular disease, hypertension, stroke, dyslipidemia, and non-alcoholic fatty liver disease/steatohepatitis. Animal models employing perinatal calorie restriction recapitulate the observations made in humans. Interestingly, if continued calorie restriction is employed post-natally the late life sequelae of intra-uterine growth restriction are ameliorated. These observations linking both fetal and early post natal growth to later health is now termed the developmental origins of health and disease. To further our understanding of the mechanism of how early growth affects late life health we have employed Affymetrix microarray-based expression profiling to characterize hepatic gene expression in a rat model of maternal semi-nutrient restriction. In these experiments we have limited maternal calorie intake to 50% of normal so as to create 3 groups of animals: Control (Con) male offspring born to mothers who were fed normally throughout gestation and lactation; intra-uterine calorie restricted male offspring (IUCR) born to mothers who had 50% restriction of calories from e11 to e21; and combined intra-uterine and post-natal calorie restriction (IPCR) male offspring who were born to mothers who received calorie restriction during both fetal growth (e11 to e21) and post-natally (p1-p21). Livers were collected at p21(day 21 of life) for Con and IPCR groups (IUCR withheld owing to ‘catch up” growth), and at p450 (day 450 of life) for Con, IUCR, and IPCR. The profiling data reveals clear alteration of circadian cycling at P21, and subtle changes for circadian gene expression at p450. In addition, a clear transcriptional response is found during active calorie restriction at p21 but an absence of a transcriptional response late in life at p450.
Project description:The present study aimed at investigating the hepatic metabolic alterations in transition cows by using integrative proteomics method.
Project description:In order to understand the transcriptional regulatory program of cardiomyocytes perinatal transition, we mapped chromatin accessibility, transcription-centered long-range chromatin interactions as well as gene expression in cardiomyocyte undergoing perinatal transition.
Project description:Gene expression was determined in primary rat hepatic stellate cells during the in vitro activation process in freshly isolated (4h), quiescent (1d), early activated (3d) and fully activated (7d) hepatic stellate cells. The cells were isolated from the liver using density centrifugation and cultured on plastic in DMEM containing serum for the indicated time. RNA was isolated using the Qiagen Rneasy Mini Kit. The Affymetrix Gene Chip Rat Gene 2.0 ST was used for gene expression analysis performed by the genomic core facility of the EMBL (Heidelberg, Germany). All experiments were performed three times with independent animals.
Project description:The period of development from the last two weeks of gestation through the first two weeks of life spans a period of great functional and metabolic challenge to the fetal and neonatal lamb heart. Important changes in gene expression occur to meet these challenges. On this study, septa from sheep hearts at 130 days gestation (n=6), term (n=8, gestational lenght is around 145 days) and 14-days-old lambs (n=8) were used to model the changes in gene expression patterns during the perinatal period using Agilent 15k ovine microarrays. Weighted gene co-expression network analysis (WGCNA) determined five major patterns of co-expressed and functionally related genes during this critical period of cardiac transition. Septum samples from the heart were collected from non-treated fetuses at 130 days of gestational age (GA130d, n=6) and term (n=8); and from naturally born 14-days-old lambs (Lamb, n=8). None of the ewes suffered gestational diseases or showed signs of impending labor.
Project description:To investigate the expression of pancreatic miRNAs during the period of perinatal beta-cell expansion and maturation in rats, RNA was extracted from whole pancreas at embryonic day 20 (E20), on the day of birth (P0) and two days after birth (P2) and hybridized to miRCURY LNA microRNA Arrays ver.8.1 (Exiqon). Labeling swaps were performed for technical duplicates of each sample. A common reference pool was generated by combining the three biologically different RNA pools from all three time points. All samples were analysed against this common reference.