242 Divergent Selection for Early Puberty Impacts KNDy Neuron Gene Expression in Gilts

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 127-128
Author(s):  
KaLynn Harlow ◽  
Allison Renwick ◽  
Sydney Shuping ◽  
Jeff Sommer ◽  
Mark Knauer ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Pubertal Development ◽  
Swine Production ◽  
Early Puberty ◽  
Hypothalamic Arcuate Nucleus ◽  
Puberty Onset ◽  
Selection For ◽  
Lh Secretion ◽  
Sectioned Tissue

Abstract Advancing gilt puberty onset is financially desirable for swine production. Neurons in the hypothalamic arcuate nucleus (ARC) that co-express kisspeptin, neurokinin B (NKB), and dynorphin (i.e. KNDy cells) are believed to control gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion, but their role in gilt pubertal development is unknown. We hypothesized that puberty onset in gilts would coincide with greater expression of mRNA for kisspeptin and NKB, and less expression of dynorphin. Using fluorescent in situ hybridization (RNAscope), we examined expression of kisspeptin, NKB, and dynorphin in pre- and postpubertal gilts from two genetic lines divergently selected for age at puberty. Prepubertal (n = 6/line) and postpubertal (n = 6/line) gilts were used, and postpubertal animals all received Matrix (0.22% altrenogest) orally for 14 days with tissue collection two days after the final dose. Gilts were euthanized and heads were perfused with 8 L of 4% paraformaldehyde (PFA). Hypothalamic brain tissue was removed, placed in 4% PFA for 24 hrs, and then in 20% sucrose until sectioning (50 µm). Sectioned tissue was stored in cryopreservative at -20°C until RNAscope. Data were analyzed using SAS software (Version 9.4, SAS Institute, Cary NC) with significance declared at P < 0.05. We determined mRNA expression for kisspeptin was not different between groups (P > 0.05). In addition, we found that mRNA expression for NKB was higher in prepubertal gilts compared to postpubertal gilts (P < 0.05) but was not different between lines; mRNA expression was lowest in postpubertal late puberty gilts. Furthermore, total number of dynorphin cells were higher in prepubertal gilts compared to postpubertal gilts (P < 0.05), while individual cell mRNA expression for dynorphin was greatest in postpubertal early puberty gilts (P < 0.05). Taken together, we suggest puberty onset in gilts is more dependent on NKB and dynorphin than kisspeptin.

scholarly journals Kisspeptin, Neurokinin B, and Dynorphin Expression during Pubertal Development in Female Sheep

Biology ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 988
Author(s):  
Eliana G. Aerts ◽  
KaLynn Harlow ◽  
Max J. Griesgraber ◽  
Elizabeth C. Bowdridge ◽  
Steven L. Hardy ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Pubertal Development ◽  
Pulse Frequency ◽  
Neurokinin B ◽  
Immunopositive Cell ◽  
Hypothalamic Tissue ◽  
Puberty Onset ◽  
Kndy Neurons ◽  
Lh Secretion ◽  
Female Sheep

The neural mechanisms underlying increases in gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion that drive puberty onset are unknown. Neurons coexpressing kisspeptin, neurokinin B (NKB), and dynorphin, i.e., KNDy neurons, are important as kisspeptin and NKB are stimulatory, and dynorphin inhibitory, to GnRH secretion. Given this, we hypothesized that kisspeptin and NKB expression would increase, but that dynorphin expression would decrease, with puberty. We collected blood and hypothalamic tissue from ovariectomized lambs implanted with estradiol at five, six, seven, eight (puberty), and ten months of age. Mean LH values and LH pulse frequency were the lowest at five to seven months, intermediate at eight months, and highest at ten months. Kisspeptin and NKB immunopositive cell numbers did not change with age. Numbers of cells expressing mRNA for kisspeptin, NKB, or dynorphin were similar at five, eight, and ten months of age. Age did not affect mRNA expression per cell for kisspeptin or NKB, but dynorphin mRNA expression per cell was elevated at ten months versus five months. Thus, neither KNDy protein nor mRNA expression changed in a predictable manner during pubertal development. These data raise the possibility that KNDy neurons, while critical, may await other inputs for the initiation of puberty.

Evidence that pubertal status impacts KNDy neurons in the gilt

2021 ◽  
Author(s):  
KaLynn Harlow ◽  
Allison N Renwick ◽  
Sydney L Shuping ◽  
Jeffrey R Sommer ◽  
Clay A Lents ◽  
...  
Keyword(s):  
Fluorescent In Situ Hybridization ◽  
Pubertal Status ◽  
Early Follicular Phase ◽  
Hypothalamic Arcuate Nucleus ◽  
Hypothalamic Tissue ◽  
Timing Of Puberty ◽  
Puberty Onset ◽  
Kndy Neurons ◽  
Lh Secretion

Abstract Puberty onset is a complex physiological process which enables the capacity for reproduction through increased gonadotropin-releasing hormone (GnRH), and subsequently luteinizing hormone (LH), secretion. While cells that coexpress kisspeptin, neurokinin B (NKB), and dynorphin in the hypothalamic arcuate nucleus (ARC) are believed to govern the timing of puberty, the degree to which KNDy neurons exist and are regulated by pubertal status remains to be determined in the gilt. Hypothalamic tissue from prepubertal and postpubertal, early follicular phase gilts was used to determine the expression of kisspeptin, NKB, and dynorphin within the ARC. Fluorescent in situ hybridization revealed that the majority (> 74%) of ARC neurons that express mRNA for kisspeptin coexpressed mRNA for NKB and dynorphin. There were fewer ARC cells that expressed mRNA for dynorphin in postpubertal gilts compared to prepubertal gilts (P < 0.05), but the number of ARC cells expressing mRNA for kisspeptin or NKB was not different between groups. Within KNDy neurons, mRNA abundance for kisspeptin, NKB, and dynorphin of postpubertal gilts was the same as, less than, and greater than, respectively, prepubertal gilts. Immunostaining for kisspeptin did not differ between prepubertal and postpubertal gilts, but there were fewer NKB immunoreactive fibers in postpubertal gilts compared to prepubertal gilts (P < 0.05). Together, these data reveal novel information about KNDy neurons in gilts and supports the idea that NKB and dynorphin play a role in puberty onset in the female pig.

scholarly journals Downregulation of TTF1 in the rat hypothalamic ARC or AVPV nucleus inhibits Kiss1 and GnRH expression, leading to puberty delay

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Shaolian Zang ◽  
Xiaoqin Yin ◽  
Pin Li
Keyword(s):  
Pubertal Development ◽  
Gonad Development ◽  
Gene Promoter ◽  
Female Rats ◽  
Luciferase Reporter ◽  
Vaginal Opening ◽  
Early Puberty ◽  
Puberty Onset

Abstract Background TTF1 is a transcription factor that is expressed in the hypothalamus after birth and plays crucial roles in pubertal development. TTF1 may regulate the expression of the Kiss1 gene, which may drive puberty onset in the hypothalamic arcuate (ARC) and anterior ventral paraventricular (AVPV) nuclei. Methods A dual-luciferase reporter assay was used to detect binding between TTF1 and the Kiss1 gene promoter. To investigate the effects of TTF1, we modified TTF1 expression in cell lines and in the ARC or AVPV nucleus of 21-day-old female rats via lentivirus infection. TTF1 and other puberty onset-related genes were detected by qRT-PCR and western blot analyses. Results The in vitro data indicated that TTF1 knockdown (KD) significantly reduced Kiss1 and GnRH expression. Overexpression (OE) of TTF1 promoted Kiss1 expression. In vivo, the expression of Kiss1 and GnRH decreased significantly in the rats with hypothalamic ARC- or AVPV-specific TTF1 KD. The TTF1-KD rats showed vaginal opening delay. H&E staining revealed that the corpus luteum was obviously reduced at the early puberty and adult stages in the rats with ARC- or AVPV-specific TTF1 KD. Conclusion TTF1 bound to the promoter of the Kiss1 gene and enhanced its expression. For 21-day-old female rats, decreased TTF1 in the hypothalamic ARC or AVPV nucleus resulted in delayed vaginal opening and ovarian abnormalities. These observations suggested that TTF1 regulates puberty onset by promoting the expression of Kiss1 and plays an important role in gonad development.

scholarly journals Expression of Kisspeptin, Neurokinin B, and Dynorphin During Pubertal Development in Female Sheep

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A539-A539
Author(s):  
Eliana G Aerts ◽  
KaLynn E Harlow ◽  
Max J Griesgraber ◽  
Elizabeth C Bowdridge ◽  
Steven L Hardy ◽  
...  
Keyword(s):  
Pubertal Development ◽  
Age Groups ◽  
Receptor Expression ◽  
Neuron Activity ◽  
Neurokinin B ◽  
Cell Numbers ◽  
Puberty Onset ◽  
Lh Secretion ◽  
Female Sheep ◽  
Over Time

Abstract Puberty onset depends upon an increase in pulsatile GnRH/LH secretion, which in sheep is the result of reduced sensitivity to estrogen negative feedback. Neurons within the arcuate nucleus of the hypothalamus (ARC) expressing kisspeptin, neurokinin B (NKB), and dynorphin (i.e. KNDy neurons) express estrogen receptors and are believed to play a key role in mediating the effects of estrogen on GnRH/LH secretion. Therefore, the purpose of this study was to assess changes in kisspeptin, NKB, and dynorphin within the ARC across pubertal development in female sheep. Blood samples were collected at 12-minute intervals for 4 hours and assessed for LH secretion in five age groups of ewes: 5 months (n=6), 6 months (n=6), 7 months (n=5), 8 months (n=5), and 10 months (n=6) of age. Following each bleed, ewes were sacrificed, hypothalamic tissue containing the ARC was collected, and then processed for use in dual immunofluorescence and RNAscope. Mean LH and LH pulse frequencies followed the expected patterns: concentrations and frequencies were low during the prepubertal ages (5-7 months of age), intermediate during the peripubertal age (8 months of age), and elevated in the postpubertal age group (10 months of age). Using immunofluorescence, kisspeptin and NKB immuno-positive cell numbers did not change significantly (P > 0.50) over time with cell numbers averaging 235.3±16.8 and 231.3±16.8, respectively. Colocalization of kisspeptin and NKB was greater than 90% for all age groups. Using RNAscope, the total number of cells expressing mRNA for kisspeptin and dynorphin did not change significantly (P > 0.05) over time with cell numbers averaging 46.7±12.0 and 28.3±10.0 cells/hemisection, respectively. Taken together, our data suggest that the increase in LH secretion that drives puberty onset is not limited by changes in kisspeptin, NKB, or dynorphin expression, but may instead depend on other factors such as changes in receptor expression or changes in KNDy neuron activity via a reduction in inhibitory and/or an increase in stimulatory afferent inputs.

Pubertal development and adult height in patients with congenital hypothyroidism detected by neonatal screening in southern Brazil

2020 ◽  
Vol 33 (11) ◽  
pp. 1449-1455
Author(s):  
Suzana Nesi-França ◽  
Rodrigo B. Silveira ◽  
Juliana Cristina R. Rojas Ramos ◽  
Adriane A. Cardoso-Demartini ◽  
Monica N. Lima Cat ◽  
...  
Keyword(s):  
Congenital Hypothyroidism ◽  
Neonatal Screening ◽  
Adult Height ◽  
Screening Program ◽  
Pubertal Development ◽  
Z Score ◽  
Normal Range ◽  
Adequate Treatment ◽  
Increased Risk ◽  
Puberty Onset

AbstractObjectivesAdequate treatment of congenital hypothyroidism (CH) is required for normal growth and sexual development. To evaluate pubertal development in patients with permanent CH detected by a statewide Neonatal Screening Program of Paraná and, secondly, to evaluate adult height (AH) in a subgroup of patients.MethodsClinical, laboratory, and auxological data obtained from medical records of 174 patients (123 girls).ResultsMedian chronological age (CA) at treatment initiation was 24 days, and mean initial levothyroxine dose was 11.7 ± 1.9 μg/kg/day; mean CA at puberty onset was 11.5 ± 1.3 years (boys) and 9.7 ± 1.2 years (girls); mean CA in girls who underwent menarche (n=81) was 12.1 ± 1.1 years. Thyroid-stimulating hormone (TSH) values above the normal range were observed in 36.4% of the boys and 32.7% of the girls on puberty onset, and in 44.6% around menarche. Among 15 boys and 66 girls who had reached the AH, the median height z-score value was significantly greater than the target height (TH) z-score value in boys (p=0.01) and in girls (p<0.001). Boys with normal TSH values at puberty onset had greater mean AH z-score compared with boys with TSH values above the normal range (p=0.04).ConclusionsIn this group, pubertal development in girls with CH was not different from that reported in healthy girls in the general Brazilian population. Boys with higher TSH at puberty onset may have an increased risk of not reaching their potential height compared with those with normal TSH during this period. In a subgroup who attained AH, the median AH z-score was greater than the median TH z-score.

scholarly journals Socioeconomic Status Is Related to Pubertal Development in a German Cohort

2021 ◽  
pp. 1-10
Author(s):  
Lea Oelkers ◽  
Mandy Vogel ◽  
Agnes Kalenda ◽  
Hans Christian Surup ◽  
Antje Körner ◽  
...  
Keyword(s):  
Socioeconomic Status ◽  
Weight Status ◽  
Pubertal Development ◽  
Serum Levels ◽  
Healthy Children ◽  
Anthropometric Parameters ◽  
Pubertal Onset ◽  
Child Study ◽  
Serum Lh ◽  
Puberty Onset

Introduction: Current health literature suggests that there has been a decline in the age of pubertal onset and that pubertal onset/duration of puberty may, besides weight status, be influenced by socioeconomic context. Objective: The goal of this study was to determine whether pubertal onset/duration and puberty-triggering hormones luteinizing hormone (LH) and follicle-stimulating hormone (FSH) vary according to socioeconomic status (SES). Moreover, we aimed to propose cutoff values of serum LH and FSH for predicting gonadarche in boys. Methods: 2,657 apparently healthy children and adolescents between 5.5 and 18 years from the area of Leipzig were recruited from the LIFE Child study. Age at pubertal onset/end of puberty was given in 738/573 children, respectively. Anthropometric parameters of puberty, blood measurements of LH and FSH, and questionnaires assessing SES were evaluated. Results: Lower SES was associated with earlier thelarche and longer duration of puberty in overweight/obese girls, whereas age of menarche was not affected. In boys with low SES, a trend versus earlier puberty onset can be seen. Lower SES was significantly associated with boys’ age at mutation. No significant differences in boys’ and girls’ serum levels of LH and FSH during puberty according to SES were observed. Serum LH levels of 0.56 IU/L and serum FSH levels of 1.74 IU/L showed the best prediction of gonadarche in boys. Conclusion: Puberty onset/duration and boys’ age at mutation is affected by SES. The proposed cutoff levels for serum LH and FSH could provide a serological tool to determine gonadarche in boys.

Expression of transforming growth factor alpha during development

1988 ◽  
Vol 66 (8) ◽  
pp. 1113-1121 ◽  
Author(s):  
V. K. M. Han ◽  
A. J. D'Ercole ◽  
D. C. Lee
Keyword(s):  
In Situ Hybridization ◽  
Growth Factor ◽  
Mrna Expression ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Alpha ◽  
Egf Receptors ◽  
Hybridization Histochemistry ◽  
In Situ Hybridization Histochemistry ◽  
Factor Alpha

Transforming growth factors (TGFs) are polypeptides that are produced by transformed and tumour cells, and that can confer phenotypic properties associated with transformation on normal cells in culture. One of these growth-regulating molecules, transforming growth factor alpha (TGF-α), is a 50 amino acid polypeptide that is related to epidermal growth factor (EGF) and binds to the EGF receptor. Previous studies have shown that TGF-α is expressed during rodent embryogenesis between 7 and 14 days gestation. To investigate the cellular sites of TGF-α mRNA expression during development, we have performed Northern analyses and in situ hybridization histochemistry on the conceptus and maternal tissues at various gestational ages. Contrary to previous reports, both Northern analyses and in situ hybridization histochemistry indicate that TGF-α mRNA is predominantly expressed in the maternal decidua and not in the embryo. Decidual expression is induced following implantation, peaks at day 8, and declines through day 15 when the decidua is being resorbed. In situ hybridization revealed that expression of TGF-α mRNA is highest in the region of decidua adjacent to the embryo and is low or nondetectable in the uterus, placenta, and embryo. In addition, we could not detect TGF-α mRNA expression in other maternal tissues, indicating that the induction of TGF-α transcripts in the decidua is tissue specific, and not a pleiotropic response to changes in hormonal milieu that occur during pregnancy. The developmentally regulated expression of TGF-α mRNA in the decidua, together with the presence of EGF receptors in this tissue, suggests that this peptide may stimulate mitosis and angiogenesis locally by an autocrine mechanism. Because EGF receptors are also present in the embryo and placenta, TGF-α may act on these tissues by a paracrine or endocrine mechanism.

Estrogen-related receptor γ2 controls NaCl uptake to maintain ionic homeostasis

2021 ◽  
Author(s):  
Shang-Wu Shih ◽  
Jia-Jiun Yan ◽  
Yi-Hsing Wang ◽  
Yi-Ling Tsou ◽  
Ling Chiu ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Body Fluid ◽  
Whole Body ◽  
Ionic Homeostasis ◽  
Ion Regulation ◽  
Expression Levels ◽  
Morpholino Knockdown ◽  
Oryzias Melastigma ◽  
Euryhaline Teleost

Estrogen-related receptors (ERRs) are known to function in mammalian kidney as key regulators of ion transport-related genes; however, a comprehensive understanding of the physiological functions of ERRs in vertebrate body fluid ionic homeostasis is still elusive. Here, we used medaka (Oryzias melastigma), a euryhaline teleost, to investigate how ERRs are involved in ion regulation. After transferring medaka from hypertonic seawater to hypotonic freshwater (FW), the mRNA expression levels of errγ2 were highly upregulated, suggesting that ERRγ2 may play a crucial role in ion uptake. In situ hybridization and immunofluorescence staining showed that errγ2 was specifically expressed in ionocytes, the cells responsible for Na+/Cl- transport. In normal FW, ERRγ2 morpholino knockdown caused reductions in the mRNA expression of Na+/Cl- cotransporter (NCC), the number of NCC ionocytes, Na+/Cl- influxes of ionocytes, and whole-body Na+/Cl- contents. In FW with low Na+ and low Cl-, the expression levels of mRNA for Na+/H+ exchanger 3 (NHE3) and NCC were both decreased in ERRγ2 morphants. Treating embryos with DY131, an agonist of ERRγ, increased the whole-body Na+/Cl- contents and ncc mRNA expression in ERRγ2 morphants. As such, medaka ERRγ2 may control Na+/Cl- uptake by regulating ncc and/or nhe3 mRNA expression and ionocyte number, and these regulatory actions may be subtly adjusted depending on internal and external ion concentrations. These findings not only provide new insights into the underpinning mechanism of actions of ERRs, but also enhance our understanding of their roles in body fluid ionic homeostasis for adaptation to changing environments during vertebrate evolution.

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