Project description:There is a lack of systematic investigations of large-scale transcriptome patterns associated with normal breast development. Herein, we profiled whole-transcriptome (by microarrays) of normal mammary glands in female Sprague-Dawley rats, an animal model widely used in breast cancer research, across six distinctive developmental stages – pre-pubertal, peri-pubertal, pubertal, lactation, and adult parous and age-matched nulliparous.
Project description:Pre-pubertal (21 days old) WT or ERa knockout we compared RNA from 21-day old WT and Ex3aERKO uteri that were treated with saline vehicle (V) estradiol (E2) or IGF1 for 2 hours or 24 hours
Project description:The COPENHAGEN Puberty Study is a combined cross sectional and longitudinal population based cohort study of healthy Danish children and adolescents. The clinical evaluations were performed by trained physicians and included pubertal staging of breast development according to Tanner´s classification evaluated by palpation. As a measure of pubertal onset a testicular volume of 4 ml or a breast tanner stage of B2 or more was used for boys and girls, respectively. The mean age between two examinations where this threshold was reached was used as their age of pubertal onset. Pre- and post-pubertal samples from 20 girls and 31 boys, in total 102 samples, were normalised using a Subset quantile Within-Array Normalization (SWAN) procedure and probes containing SNPs in the CpG or extension sites were removed.
Project description:Recent studies have documented the profound impact of pre-pubertal nutrition on reproductive performance in bulls. Previously, a high plane of nutrition during calfhood (2-30 wk) in beef and dairy bulls hastened puberty explained by an increase in the level of reproductive hormones (LH, testosterone and IGF-I) pre-pubertally, compared to bulls fed less than recommended amounts of energy and protein with no apparent effect on sperm function evaluated by traditional techniques. In addition, upregulated steroid biosynthesis and Sertoli cell maturation was identified in the testicular tissue of high diet bulls at 16 and 24 weeks, respectively. The objective of this study was to evaluate the post- pubertal testes for responses to high (20.0% CP, 67.9% TDN), medium (17.0% CP, 66.0% TDN) and low (12.2% CP, 62.9% TDN) diets fed from 2-30 wk of life. Based on RNA sequencing data, 497 genes were differentially expressed in high vs low diet and 2961 genes in high vs medium diet (P<0.1). According to KEGG analysis, oxidative phosphorylation and ribosome pathways were upregulated in the high diet group (vs medium and low) with majority of the upregulated genes encoding for essential subunits of complex I, III, IV and V of OXYPHOS pathway. In addition, mitochondrial translation, mitotic nuclear division and cell division were enriched in the high vs medium diet group. Supporting the above, the percentage of sperm exhibiting loss of mitochondrial function was lower in the high diet compared to the medium diet (P<0.1). Thus, enhanced early life nutrition upregulated mitochondrial function in both the testes and sperm of post-pubertal Holstein bulls.
Project description:Expression profile of colon mucosa of F344 rats treated with 5% DSS during five days vs colon mucosa of F344 rats pre-treated for 20 days with resveratrol 1mg/kg/day and during the five days of 5% DSS administration Keywords: Inflammation experiment Two conditions experiment, colon mucosa of F344 rats treated 5% DSS for 5d vs colon mucosa of F344 rats pretreated with 1mg/kg/day resv + 5% DSS for 5d. 8 Biological samples for each group
Project description:Pre-pubertal Holstein bull calves fed a higher plane of nutrition had larger testes, earlier puberty, higher serum LH, testosterone and greater sperm production potential than those fed a restricted diet. In addition, pre-pubertal calves fed a high-nutrition diet had higher IGF-I and more proliferating and differentiating Sertoli cells much earlier in life, compared to those fed normal or low-nutrition diets. The objective was to determine changes in mRNA expression of genes in the testes of bulls fed either a high or low pre-pubertal diet. Holstein bull calves maintained on either a high (20% crude protein (CP) and 71.6% Total Digestible Nutrients (TDN)) or low (12% CP and 64.4% TDN) diet from 2 wk of age, were castrated at 8, 16, 24 and 32 wk and testicular mRNA extracted and sequenced. Differential expression of genes mainly occurred at 16 and 24 wk, with minor changes detected at 32 wk. At 16 wks, functional analysis of DE mRNA with DAVID revealed the common biological processes enriched to be "cholesterol" and "fatty acid biosynthesis" with majority of the genes including HMGCR, HMGCS1, HSD17 being upregulated in high-diet bulls (P<0.05). Major pathways enriched at 16 wks were "cholesterol biosynthesis", "steroid metabolism" and "activation of gene expression by Sterol regulatory element-binding protein (SREBP)" (P<0.05). Mature Sertoli cell marker Connexin 43, was upregulated at 16 wk, whereas an immature Sertoli cell marker, AMH was downregulated at 24 wk, in the high-diet group. Network analysis using IPA, revealed an indirect interaction between insulin family receptor and most upregulated cholesterol biosynthesis genes, implying regulation of testicular function. Thus, enhanced pre-pubertal nutrition in Holstein bulls enhanced testicular cholesterol/steroid biosynthesis and Sertoli cell maturation to promote early reproductive development.
Project description:Several lines of evidence indicate one's age at exposure to radiation strongly modifies the risk of radiation-induced breast cancer. We previously reported that rat mammary carcinomas induced by pre- and post-pubertal irradiation have distinct gene expression patterns, but the changes underlying these differences have not yet been characterized. The aim of this investigation was to see if differences in CpG DNA methylation were responsible for the differences in gene expression between age at exposure groups observed in our previous study.