Project description:Addictive drugs including opioids activate signal transduction pathways that regulate gene expression in the brain. However, changes in CNS gene expression following morphine exposure are poorly understood. We studied the effect of short- and long-term morphine treatment on gene expression in the hypothalamus and pituitary using genome-wide DNA microarray and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analyses. In the hypothalamus, we found that short-term morphine administration up-regulated (at least 2-fold) 39 genes and down-regulated six genes. Long-term morphine administration up-regulated 35 genes and down-regulated 51 hypothalamic genes. In the pituitary, we found that short-term morphine administration up-regulated (at least 2-fold) 110 genes and down-regulated 29 genes. Long-term morphine administration up-regulated 85 genes and down-regulated 37 pituitary genes. Strikingly, microarray analysis uncovered several genes involved in food intake (neuropeptide Y, agouti-related protein, and cocaine and amphetamine-regulated transcript) whose expression was strongly altered by morphine exposure in either the hypothalamus or pituitary. Subsequent RT-PCR analysis confirmed similar gene regulation of noteworthy genes in these regions. Finally, we found functional correlation between morphine-induced alterations in food intake and regulations of genes involved in this process. Changes in genes related to food intake may uncover new pathways related to some of the physiological effects of opioids. Keywords: Comparative treatment versus placebo 8 samples analyzed: 4 from hypothalamus (2 biological replicates and 2 dye swaps) and 4 from pituitary (2 biological replicates and 2 dye swaps) 8 samples analyzed: 4 from hypothalamus short term treatment (2 biological replicates and 2 dye swaps) and 4 hypothalamus long term treatment (2 biological replicates and 2 dye swaps)
Project description:Addictive drugs including opioids activate signal transduction pathways that regulate gene expression in the brain. However, changes in CNS gene expression following morphine exposure are poorly understood. We studied the effect of short- and long-term morphine treatment on gene expression in the hypothalamus and pituitary using genome-wide DNA microarray and real-time reverse transcriptase polymerase chain reaction (RT-PCR) analyses. In the hypothalamus, we found that short-term morphine administration up-regulated (at least 2-fold) 39 genes and down-regulated six genes. Long-term morphine administration up-regulated 35 genes and down-regulated 51 hypothalamic genes. In the pituitary, we found that short-term morphine administration up-regulated (at least 2-fold) 110 genes and down-regulated 29 genes. Long-term morphine administration up-regulated 85 genes and down-regulated 37 pituitary genes. Strikingly, microarray analysis uncovered several genes involved in food intake (neuropeptide Y, agouti-related protein, and cocaine and amphetamine-regulated transcript) whose expression was strongly altered by morphine exposure in either the hypothalamus or pituitary. Subsequent RT-PCR analysis confirmed similar gene regulation of noteworthy genes in these regions. Finally, we found functional correlation between morphine-induced alterations in food intake and regulations of genes involved in this process. Changes in genes related to food intake may uncover new pathways related to some of the physiological effects of opioids. Keywords: Comparative treatment versus placebo
Project description:We compared the gene expression of ventral part of telenchephalon, hypothalamus and pituitary using RNA-seq between the two comparison groups, medaka kept under short day and long day.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:Opioid analgesics are frequently prescribed in the United States and worldwide. However, serious side effects such as addiction, immunosuppression and gastrointestinal symptoms limit long term use. In the current study using a chronic morphine-murine model a longitudinal approach was undertaken to investigate the role of morphine modulation of gut microbiome as a mechanism contributing to the negative consequences associated with opioids use. The results revealed a significant shift in the gut microbiome and metabolome within 24 hours following morphine treatment when compared to placebo. Morphine induced gut microbial dysbiosis exhibited distinct characteristic signatures profiles including significant increase in communities associated with pathogenic function, decrease in communities associated with stress tolerance. Collectively, these results reveal opioids-induced distinct alteration of gut microbiome, may contribute to opioids-induced pathogenesis. Therapeutics directed at these targets may prolong the efficacy long term opioid use with fewer side effects.
Project description:Sex differences in liver gene expression are dictated by sex-differences in circulating growth hormone (GH) profiles. Presently, the pituitary hormone dependence of mouse liver gene expression was investigated on a global scale to discover sex-specific early GH response genes that might contribute to sex-specific regulation of downstream GH targets and to ascertain whether intrinsic sex-differences characterize hepatic responses to plasma GH stimulation. RNA expression analysis using 41,000-feature microarrays revealed two distinct classes of sex-specific mouse liver genes: genes subject to positive regulation (class-I) and genes subject to negative regulation by pituitary hormones (class-II). Genes activated or repressed in hypophysectomized (Hypox) mouse liver within 30-90min of GH pulse treatment at a physiological dose were identified as direct targets of GH action (early response genes). Intrinsic sex-differences in the GH responsiveness of a subset of these early response genes were observed. Notably, 45 male-specific genes, including five encoding transcriptional regulators that may mediate downstream sex-specific transcriptional responses, were rapidly induced by GH (within 30min) in Hypox male but not Hypox female mouse liver. The early GH response genes were enriched in 29 male-specific targets of the transcription factor Mef2, whose activation in hepatic stellate cells is associated with liver fibrosis leading to hepatocellular carcinoma, a male-predominant disease. Thus, the rapid activation by GH pulses of certain sex-specific genes is modulated by intrinsic sex-specific factors, which may be associated with prior hormone exposure (epigenetic mechanisms) or genetic factors that are pituitary-independent, and could contribute to sex-differences in predisposition to liver cancer or other hepatic pathophysiologies.
Project description:The crucial role of nutrition for cerebral health and the impact of dietary habits on brain structure and function have been long far recognized. To date a major health concern is associated with the increased consumption of fructose as added sugar in many types of drinks and processed foods, especially among young people. High-fructose intake has been pointed out as the possible culprit for the raised incidence of chronic diseases, such as obesity, cardiovascular disease, nonalcoholic fatty liver disease, and type 2 diabete. Further, it has been reported that high-fructose intake is associated with the over-activation of its cerebral metabolism, which was proposed to negatively impact on whole brain physiology and cognitive function. Notably, we previously reported that short-term fructose-rich diet induces mitochondrial dysfunction, oxidative stress, and neuroinflammation in hippocampus of young rats, as well as the imbalance of redox homeostasis, autophagic mechanisms and representation of synaptic markers in frontal cortex of both adult and young rats. Animal studies have also revealed the damaging effect of high-fructose diets on hippocampal functions during periods of neurocognitive development, such as childhood and adolescence. Hypothalamus plays a crucial role in maintaining whole body homeostasis. Long-term fructose overfeeding was reported to alter hypothalamic-pituitary-adrenal axis, leading to elevations in glucocorticoids in peri-adolescent rats [22]. Further, fructose overconsumption was associated with impairment of hypothalamic insulin signalling, oxidative stress and inflammation , and it was proposed that fructose-driven perturbations of hypothalamic function may compromise the potential for satiety, thereby increasing the prospect of developing obesity. Data currently available on hypothalamic dysfunctions related to a high-fructose diet essentially refer to the effects of long-term sugar feeding, while information on corresponding alterations associated with a short-term dietary treatment, particularly in the critical period of adolescence, is still lacking. Due to complexity and multiplicity of hypothalamic functions, there is also the need for a holistic characterization aimed at unveiling the general picture of hypothalamic dysfunctions associated with a high-fructose diet. To fill this gap, we investigated adolescent rats fed a fructose-rich or control diet, for 3 weeks. To verify whether the fructose-driven changes are rescued after the switch to a control diet, half of the rats from both animal groups were then fed a control diet for additional 3 weeks until young adulthood phase. Quantitative proteomics on hypothalamic extracts of all animal groups was used to identify molecular alterations triggered by fructose-rich diet and to obtain insights into the relationship between sugar feeding and possible dysfunctions of hypothalamus.
Project description:To examine the seasonal adaptaion, we compared the gene expression of brains (ventral part of telenchephalon, hypothalamus and pituitary) between SD (short-day conditions: 10 h light/14 h dark and 26 °C) and LD (long-day conditions: 14 h light/10 h dark and 26 °C) conditions in Medaka fish (Oryzias latipes).
Project description:Translational research is commonly performed in the C57B6/J mouse strain, chosen for its genetic homogeneity and phenotypic uniformity. Here, we evaluate the suitability of the white-footed deer mouse (Peromyscus leucopus) as a model organism for aging research, offering a comparative analysis against C57B6/J and diversity outbred (DO) Mus musculus strains. Our study includes comparisons of body composition, skeletal muscle function, and cardiovascular parameters, shedding light on potential applications and limitations of P. leucopus in aging studies. Notably, P. leucopus exhibits distinct body composition characteristics, emphasizing reduced muscle force exertion and a unique metabolism, particularly in fat mass. Cardiovascular assessments showed changes in arterial stiffness, challenging conventional assumptions and highlighting the need for a nuanced interpretation of aging-related phenotypes. Our study also highlights inherent challenges associated with maintaining and phenotyping P. leucopus cohorts. Behavioral considerations, including anxiety-induced responses during handling and phenotyping assessment, pose obstacles in acquiring meaningful data. Moreover, the unique anatomy of P. leucopus necessitates careful adaptation of protocols designed for Mus musculus. While showcasing potential benefits, further extensive analyses across broader age ranges and larger cohorts are necessary to establish the reliability of P. leucopus as a robust and translatable model for aging studies.