scholarly journals GABAergic input through GABAB receptors is necessary during a perinatal window to shape gene expression of factors critical to reproduction such as Kiss1

2020 ◽  
Vol 318 (6) ◽  
pp. E901-E919 ◽  
Author(s):  
Marianne Bizzozzero-Hiriart ◽  
Noelia P. Di Giorgio ◽  
Carlos Libertun ◽  
Victoria Lux-Lantos

Lack of GABAB receptors in GABAB1 knockout mice decreases neonatal ARC kisspeptin 1 ( Kiss1) expression in the arcuate nucleus of the hypothalamus (ARC) in females, which show impaired reproduction as adults. Our aim was to selectively impair GABAB signaling during a short postnatal period to evaluate its impact on the reproductive system. Neonatal male and female mice were injected with the GABAB antagonist CGP 55845 (CGP, 1 mg/kg body wt sc) or saline from postnatal day 2 ( PND2) to PND6, three times per day (8 AM, 1 PM, and 6 PM). One group was killed on PND6 for collection of blood samples (hormones by radioimmunoassay), brains for gene expression in the anteroventral periventricular nucleus-periventricular nucleus continuum (AVPV/PeN), and ARC micropunches [quantitative PCR (qPCR)] and gonads for qPCR, hormone contents, and histology. A second group of mice was injected with CGP (1 mg/kg body wt sc) or saline from PND2 to PND6, three times per day (8 AM, 1 PM, and 6 PM), and left to grow to adulthood. We measured body weight during development and parameters of sexual differentiation, puberty onset, and estrous cycles. Adult mice were killed, and trunk blood (hormones), brains for qPCR, and gonads for qPCR and hormone contents were obtained. Our most important findings on PND6 include the CGP-induced decrease in ARC Kiss1 and increase in neurokinin B ( Tac2) in both sexes; the decrease in AVPV/PeN tyrosine hydroxylase ( Th) only in females; the increase in gonad estradiol content in both sexes; and the increase in primordial follicles and decrease in primary and secondary follicles. Neonatally CGP-treated adults showed decreased ARC Kiss1 and ARC gonadotropin-releasing hormone ( Gnrh1) and increased ARC glutamic acid decarboxylase 67 ( Gad1) only in males; increased ARC GABAB receptor subunit 1 ( Gabbr1) in both sexes; and decreased AVPV/PeN Th only in females. We demonstrate that ARC Kiss1 expression is chronically downregulated in males and that the normal sex difference in AVPV/PeN Th expression is abolished. In conclusion, neonatal GABAergic input through GABAB receptors shapes gene expression of factors critical to reproduction.

2021 ◽  
Author(s):  
Marianne Bizzozzero Hiriart ◽  
Noelia P. Di Giorgio ◽  
Carlos Libertun ◽  
Victoria A.R. Lux-Lantos

Introduction: The kisspeptin gene Kiss1 is expressed in two hypothalamic areas: anteroventral periventricular nucleus/periventricular nucleus (AVPV/PeN) and arcuate nucleus (ARC), and also in gonads. Evidences suggest that gamma-amino butyric acid B receptors (GABAB) signaling can regulate Kiss1 expression. Here we inhibited GABAB signaling from PND2-PND21 and evaluated the hypothalamic-pituitary-gonadal (HPG) axis. Methods: BALB/c mice were treated on postnatal days 2-21 (PND2-PND21) with CGP55845 (GABAB antagonist), and evaluated in PND21 and adulthood: gene expression (qPCR) in hypothalamus and gonads, hormones by radioimmunoassay, gonad histochemistry (H&E), puberty onset, estrous cycles. Results: At PND21, CGP inhibited Kiss1 and Tac2 and increased Pdyn and Gabbr1 in the ARC of both sexes and decreased Th only in female AVPV/PeN. Serum follicle-stimulating hormone (FSH) and testis weight decreased in CGP-males and puberty onset was delayed. In adults, Kiss1, Tac2, Pdyn, Pgr, Cyp19a1, Gad1 were downregulated, while Gabbr1 was upregulated in the ARC of both sexes. In the AVPV/PeN, Kiss1, Th, Cyp19a1 and Pgr decreased while Gad1 increased in CGP-females, whereas Cyp19a1 increased in CGP-males. Serum FSH increased in CGP-males while prolactin increased in CGP-females. Testosterone and progesterone increased in ovaries from CGP-females, in which Kiss1, Cyp19a1 and Esr1 were downregulated while Hsd3b2 was upregulated, together with increased atretic and decreased ovulatory follicles. Testes from CGP-males showed decreased progesterone, increased Gabbr1, Kiss1, Kiss1r, Esr2 and decreased Cyp19a1 and clear signs of seminiferous tubules atrophy. Conclusion: These results demonstrate that appropriate GABAB signaling during this critical prepubertal period is necessary for the normal development of the HPG axis.


2021 ◽  
Vol 22 (12) ◽  
pp. 6570
Author(s):  
Yue Lv ◽  
Rui-Can Cao ◽  
Hong-Bin Liu ◽  
Xian-Wei Su ◽  
Gang Lu ◽  
...  

A better understanding of the mechanism of primordial follicle activation will help us better understand the causes of premature ovarian insufficiency (POI), and will help us identify new drugs that can be applied to the clinical treatment of infertility. In this study, single oocytes were isolated from primordial and primary follicles, and were used for gene profiling with TaqMan array cards. Bioinformatics analysis was performed on the gene expression data, and Ingenuity Pathway Analysis was used to analyze and predict drugs that affect follicle activation. An ovarian in vitro culture system was used to verify the function of the drug candidates, and we found that curcumin maintains the ovarian reserve. Long-term treatment with 100 mg/kg curcumin improved the ovarian reserve indicators of AMH, FSH, and estradiol in aging mice. Mechanistic studies show that curcumin can affect the translocation of FOXO3, thereby inhibiting the PTEN-AKT-FOXO3a pathway and protecting primordial follicles from overactivation. These results suggest that curcumin is a potential drug for the treatment of POI patients and for fertility preservation.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Matthieu Dos Santos ◽  
Stéphanie Backer ◽  
Benjamin Saintpierre ◽  
Brigitte Izac ◽  
Muriel Andrieu ◽  
...  

Abstract Skeletal muscle fibers are large syncytia but it is currently unknown whether gene expression is coordinately regulated in their numerous nuclei. Here we show by snRNA-seq and snATAC-seq that slow, fast, myotendinous and neuromuscular junction myonuclei each have different transcriptional programs, associated with distinct chromatin states and combinations of transcription factors. In adult mice, identified myofiber types predominantly express either a slow or one of the three fast isoforms of Myosin heavy chain (MYH) proteins, while a small number of hybrid fibers can express more than one MYH. By snRNA-seq and FISH, we show that the majority of myonuclei within a myofiber are synchronized, coordinately expressing only one fast Myh isoform with a preferential panel of muscle-specific genes. Importantly, this coordination of expression occurs early during post-natal development and depends on innervation. These findings highlight a previously undefined mechanism of coordination of gene expression in a syncytium.


2018 ◽  
Vol 100 (4) ◽  
pp. 869-871 ◽  
Author(s):  
Christian Lee Andersen ◽  
Mingjun Liu ◽  
Zidao Wang ◽  
Xiaoqin Ye ◽  
Shuo Xiao

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3071 ◽  
Author(s):  
Giustino Orlando ◽  
Sheila Leone ◽  
Claudio Ferrante ◽  
Annalisa Chiavaroli ◽  
Adriano Mollica ◽  
...  

Besides its role as key regulator in gonadotropin releasing hormone secretion, reproductive function, and puberty onset, kisspeptin has been proposed to act as a bridge between energy homeostasis and reproduction. In the present study, to characterize the role of hypothalamic kisspeptin as metabolic regulator, we evaluated the effects of kisspeptin-10 on neuropeptide Y (NPY) and brain-derived neurotrophic factor (BDNF) gene expression and the extracellular dopamine (DA), norepinephrine (NE), serotonin (5-hydroxytriptamine, 5-HT), dihydroxyphenylacetic acid (DOPAC), and 5-hydroxyindoleacetic acid (5-HIIA) concentrations in rat hypothalamic (Hypo-E22) cells. Our study showed that kisspeptin-10 in the concentration range 1 nM–10 μM was well tolerated by the Hypo-E22 cell line. Moreover, kisspeptin-10 (100 nM–10 μM) concentration independently increased the gene expression of NPY while BDNF was inhibited only at the concentration of 10 μM. Finally, kisspeptin-10 decreased 5-HT and DA, leaving unaffected NE levels. The inhibitory effect on DA and 5-HT is consistent with the increased peptide-induced DOPAC/DA and 5-HIIA/5-HT ratios. In conclusion, our current findings suggesting the increased NPY together with decreased BDNF and 5-HT activity following kisspeptin-10 would be consistent with a possible orexigenic effect induced by the peptide.


2005 ◽  
Vol 21 (3) ◽  
pp. 351-361 ◽  
Author(s):  
Ralph L. House ◽  
Joseph P. Cassady ◽  
Eugene J. Eisen ◽  
Thomas E. Eling ◽  
Jennifer B. Collins ◽  
...  

Gene expression was measured during t10c12-CLA-induced body fat reduction in a polygenic obese line of mice. Adult mice ( n = 185) were allotted to a 2 × 2 factorial experiment consisting of either nonobese (ICR-control) or obese (M16-selected) mice fed a 7% fat, purified diet containing either 1% linoleic acid (LA) or 1% t10c12-CLA. Body weight (BW) by day 14 was 12% lower in CLA- compared with LA-fed mice ( P < 0.0001). By day 14, t10c12-CLA reduced weights of epididymal, mesenteric, and brown adipose tissues, as a percentage of BW, in both lines by 30, 27, and 58%, respectively, and increased liver weight/BW by 34% ( P < 0.0001). Total RNA was isolated and pooled (4 pools per tissue per day) from epididymal adipose ( days 5 and 14) of the obese mice to analyze gene expression profiles using Agilent mouse oligo microarray slides representing >20,000 genes. Numbers of genes differentially expressed by greater than or equal to twofold in epididymal adipose ( days 5 and 14) were 29 and 125, respectively. It was concluded that, in adipose tissue, CLA increased expression of uncoupling proteins (1 and 2), carnitine palmitoyltransferase system, tumor necrosis factor-α ( P < 0.05), and caspase-3 but decreased expression of peroxisome proliferator-activated receptor-γ, glucose transporter-4, perilipin, caveolin-1, adiponectin, resistin, and Bcl-2 ( P < 0.01). In conclusion, this experiment has revealed candidate genes that will be useful in elucidating mechanisms of adipose delipidation.


2003 ◽  
Vol 90 (4) ◽  
pp. 2690-2701 ◽  
Author(s):  
Kimmo Jensen ◽  
Chi-Sung Chiu ◽  
Irina Sokolova ◽  
Henry A. Lester ◽  
Istvan Mody

After its release from interneurons in the CNS, the major inhibitory neurotransmitter GABA is taken up by GABA transporters (GATs). The predominant neuronal GABA transporter GAT1 is localized in GABAergic axons and nerve terminals, where it is thought to influence GABAergic synaptic transmission, but the details of this regulation are unclear. To address this issue, we have generated a strain of GAT1-deficient mice. We observed a large increase in a tonic postsynaptic hippocampal GABAA receptor-mediated conductance. There was little or no change in the waveform or amplitude of spontaneous inhibitory postsynaptic currents (IPSCs) or miniature IPSCs. In contrast, the frequency of quantal GABA release was one-third of wild type (WT), although the densities of GABAA receptors, GABAB receptors, glutamic acid decarboxylase 65 kDa, and vesicular GAT were unaltered. The GAT1-deficient mice lacked a presynaptic GABAB receptor tone, present in WT mice, which reduces the frequency of spontaneous IPSCs. We conclude that GAT1 deficiency leads to enhanced extracellular GABA levels resulting in an overactivation of GABAA receptors responsible for a postsynaptic tonic conductance. Chronically elevated GABA levels also downregulate phasic GABA release and reduce presynaptic signaling via GABAB receptors thus causing an enhanced tonic and a diminished phasic inhibition.


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0244793
Author(s):  
Elisa S. Na ◽  
Daniel D. Lam ◽  
Eva Yokosawa ◽  
Jessica M. Adams ◽  
David P. Olson ◽  
...  

Enhancer redundancy has been postulated to provide a buffer for gene expression against genetic and environmental perturbations. While work in Drosophila has identified functionally overlapping enhancers, work in mammalian models has been limited. Recently, we have identified two partially redundant enhancers, nPE1 and nPE2, that drive proopiomelanocortin gene expression in the hypothalamus. Here we demonstrate that deletion of nPE1 produces mild obesity while knockout of nPE2 has no discernible metabolic phenotypes. Additionally, we show that acute leptin administration has significant effects on nPE1 knockout mice, with food intake and body weight change significantly impacted by peripheral leptin treatment. nPE1 knockout mice became less responsive to leptin treatment over time as percent body weight change increased over 2 week exposure to peripheral leptin. Both Pomc and Agrp mRNA were not differentially affected by chronic leptin treatment however we did see a decrease in Pomc and Agrp mRNA in both nPE1 and nPE2 knockout calorie restricted mice as compared to calorie restricted PBS-treated WT mice. Collectively, these data suggest dynamic regulation of Pomc by nPE1 such that mice with nPE1 knockout become less responsive to the anorectic effects of leptin treatment over time. Our results also support our earlier findings in which nPE2 may only be critical in adult mice that lack nPE1, indicating that these neural enhancers work synergistically to influence metabolism.


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