Kisspeptin activates the hypothalamic–adenohypophyseal–gonadal axis in prepubertal ewe lambs

Redmond, Jeremy S; Macedo, Gustavo Guerino; Velez, I. C.; Caraty, Alain; Williams, Gary L.; Amstalden, M.

doi:10.1530/rep-10-0467

Cited by 73 publications

(68 citation statements)

References 59 publications

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“…In experiment 1, TCM-199B was supplemented with 0, 5, 10, 15 µg/ml of KP, to identify the best concentration to support oocyte maturation in terms of CCE and extrusion of the 1 st PB. In sheep, 8-20 µg of KP was infused to monitor FSH and LH hormones in earlier studies [20,21]. Based on the CCE and extrusion of PB, 10 µg/ml of KP supported better for IVM of sheep oocytes.…”

Section: Discussionmentioning

confidence: 99%

“…The ability of KP to induce ovulation following intravenous administration has been demonstrated in prepubertal ewe lambs [20] and anestrous ewes [21]. The presence of high concentrations of KP in the porcine follicular fluid than in serum (335 vs. 25 pg/mL) and expression of KISS1Rs in oocytes and cumulus cells during in vitro maturation (IVM) pig oocytes supported the local involvement of KP on the development of oocytes within the follicle [22].…”

Section: Introductionmentioning

confidence: 99%

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Effect of kisspeptin on in vitro maturation of sheep oocytes

Byri¹,

Gangineni²,

Reddy³

et al. 2017

Vet World

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Aim:The aim of this study was to investigate the effect of kisspeptin (KP) on in vitro maturation (IVM) of sheep oocytes aspirated from the ovaries collected from slaughterhouse.Materials and Methods:Two different experiments were conducted to investigate the effect of KP (5, 10 and 15 µg/ml) alone (experiment 1) or in combination with follicle-stimulating hormone (FSH), luteinizing hormone (LH), and Estradiol (E2) (experiment 2) on IVM of sheep oocytes. Tissue culture medium 199 supplemented with Gentamicin was used as control medium. Good quality oocytes were randomly allocated into different IVM media and cultured at 38.5°C in 5% CO2 under humidified atmosphere for 24 h. The oocytes were evaluated for their cumulus cell expansion (CCE) and extrusion of the 1st polar body (PB) at the end of maturation.Results:The proportion of oocytes showing CCE and extrusion of PB was highest when the oocytes were matured in the medium supplemented with 10 µg/ml of KP. In experiment 2, oocytes were matured in 12 different maturation media (G1-G12: G1: Control, G2: KP alone, G3: FSH, G4: FSH+KP, G5: LH, G6: LH+KP, G7: E2, G8: E2+KP, G9: FSH+LH+E2, G10: FSH+LH+E2+KP, G11: FSH+LH+E2+fetal bovine serum (FBS), G12: FSH+LH+E2+FBS+KP). The proportion of oocytes showing cumulus expansion and PB extrusion was highest (98.33±1.05 and 89.17±2.38) when they were matured in FSH+LH+E2+FBS+KP (G12) and was significantly higher than other groups. The proportion of CCE and extrusion of PB was significantly increased when KP was supplemented to FSH and E2, but no effect was observed with LH. The maturation rates were significantly increased when FSH, LH, and E2 (G9) containing media were additionally supplemented with KP (G10).Conclusion:This study demonstrated that the addition of KP (10 µg/ml) to the FSH, LH, and E2 supplemented media would enhance the sheep oocyte maturation in vitro.

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Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Effect of kisspeptin on in vitro maturation of sheep oocytes

Byri¹,

Gangineni²,

Reddy³

et al. 2017

Vet World

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“…Actions of kisspeptin on regulation of reproductive functions appear to be mainly by its direct effects on GnRH release (Caraty et al, 2007). Kisspeptin is a potent stimulator of LH secretion in mature (Caraty et al, 2007) and prepubertal females (Navarro et al, 2004; Kadokawa et al, 2008; Redmond et al, 2011a). In prepubertal rats, kisspeptin treatment induces early vaginal canalization (Navarro et al, 2004), indicating that puberty may be advanced by exogenous kisspeptin.…”

Section: Role Of Kisspeptin In Mediating Nutritional Acceleration Of mentioning

confidence: 99%

“…In prepubertal rats, kisspeptin treatment induces early vaginal canalization (Navarro et al, 2004), indicating that puberty may be advanced by exogenous kisspeptin. In ewe lambs, intermittent injections of kisspeptin increase ovarian steroidogenesis and leads to a preovulatory surge of LH that is followed by ovulation/follicle luteinization (Redmond et al, 2011a). …”

Section: Role Of Kisspeptin In Mediating Nutritional Acceleration Of mentioning

confidence: 99%

Neuroendocrine Pathways Mediating Nutritional Acceleration of Puberty: Insights from Ruminant Models

Amstalden¹,

Alves²,

Liu³

et al. 2011

Front. Endocrin.

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The pubertal process is characterized by an activation of physiological events within the hypothalamic-adenohypophyseal–gonadal axis which culminate in reproductive competence. Excessive weight gain and adiposity during the juvenile period is associated with accelerated onset of puberty in females. The mechanisms and pathways by which excess energy balance advances puberty are unclear, but appear to involve an early escape from estradiol negative feedback and early initiation of high-frequency episodic gonadotropin-releasing hormone (GnRH) secretion. Hypothalamic neurons, particularly neuropeptide Y and proopiomelanocortin neurons are likely important components of the pathway sensing and transmitting metabolic information to the control of GnRH secretion. Kisspeptin neurons may also have a role as effector neurons integrating metabolic and gonadal steroid feedback effects on GnRH secretion at the time of puberty. Recent studies indicate that leptin-responsive neurons within the ventral premammillary nucleus play a critical role in pubertal progression and challenge the relevance of kisspeptin neurons in this process. Nevertheless, the nutritional control of puberty is likely to involve an integration of major sensor and effector pathways that interact with modulatory circuitries for a fine control of GnRH neuron function. In this review, observations made in ruminant species are emphasized for a comparative perspective.

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“…Mice and humans lacking kisspeptin or the kisspeptin receptor fail to undergo puberty and are infertile (8–10). Central or peripheral administration of kisspeptin induces gonadotropin and sex steroid release in all mammalian species investigated, including rats (11–13), mice (14, 15), monkeys (16), and sheep (17, 18). …”

mentioning

confidence: 99%

Twice-Daily Subcutaneous Injection of Kisspeptin-54 Does Not Abolish Menstrual Cyclicity in Healthy Female Volunteers

Jayasena

Comninos

Nijher

et al. 2013

The Journal of Clinical Endocrinology &Amp; Metabolism

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Background:Kisspeptin is a critical hypothalamic regulator of reproductive function. Chronic kisspeptin administration causes profound tachyphylaxis in male monkeys and in women with functional hypothalamic amenorrhea. The pharmacological effects of chronic kisspeptin exposure in healthy women with normal menstrual cycles have not been studied previously.Aim:Our aim was to determine the effects of follicular-phase kisspeptin-54 treatment on menstrual cyclicity in healthy women.Methods:We performed a prospective, single-blinded, 1-way crossover study. Healthy women received twice-daily sc injections of kisspeptin (6.4 nmol/kg) or 0.9% saline during menstrual days 7–14 (n = 5 per treatment arm). Serial assessments of basal reproductive hormones, ultrasound parameters, LH pulsatility, and acute sensitivity to GnRH and kisspeptin-54 injection were performed.Results:Menstrual cyclicity persisted in all women after follicular-phase kisspeptin-54 treatment. Chronic exposure to kisspeptin-54 did not abolish acute stimulation of LH after injection of kisspeptin-54 or GnRH. In addition, kisspeptin-54 treatment was associated with a shorter mean length of the menstrual cycle (mean length of menstrual cycle was 28.6 ± 1.4 days with saline vs 26.8 ± 3.1 days with kisspeptin, P < .01), earlier onset of highest recorded serum LH (mean menstrual day of highest LH was 15.2 ± 1.3 with saline vs 13.0 ± 1.9 with kisspeptin, P < .05), and earlier onset of the luteal phase (mean menstrual day of progesterone increase was 18.0 ± 2.1 with saline vs 15.8 ± 0.9 with kisspeptin, P < .05).Conclusion:Our data suggest that 1 week of exogenous kisspeptin-54 does not abolish menstrual cyclicity in healthy women. Further work is needed to determine whether kisspeptin could be used to treat certain anovulatory disorders.

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Kisspeptin activates the hypothalamic–adenohypophyseal–gonadal axis in prepubertal ewe lambs

Cited by 73 publications

References 59 publications

Effect of kisspeptin on in vitro maturation of sheep oocytes

Effect of kisspeptin on in vitro maturation of sheep oocytes

Neuroendocrine Pathways Mediating Nutritional Acceleration of Puberty: Insights from Ruminant Models

Twice-Daily Subcutaneous Injection of Kisspeptin-54 Does Not Abolish Menstrual Cyclicity in Healthy Female Volunteers

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