Limits...
Unpredictable chronic stress-induced reproductive suppression associated with the decrease of kisspeptin immunoreactivity in male mice.

Hirano T, Kobayashi Y, Omotehara T, Tatsumi A, Hashimoto R, Umemura Y, Nagahara D, Mantani Y, Yokoyama T, Kitagawa H, Hoshi N - J. Vet. Med. Sci. (2014)

Bottom Line: Although the ARC was not morphologically altered in either the stressed or non-stressed group, granular kisspeptin immunoreactivities decreased slightly in the stress group.The decreases in kisspeptin in the stress group might be due to other hypothalamic peptides, such as corticotropin-releasing hormone and leptin, whose receptors are known to coexpress in the ARC.In addition, environmental stress directly and indirectly affects testicular function through stress hormones and gonadotropins.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.

ABSTRACT
Environmental stress affects various parts of mammals typically through the circulation of stress hormones. It has been identified as one of the possible reasons for male reproductive difficulties, but the complex mechanisms responsible for stress-induced reproductive suppression are poorly understood. Here, we examined the relationship between chronic environmental stress and hypothalamic kisspeptin, a recently discovered upstream regulator of the reproductive endocrine feedback system. We studied male mice under an unpredictable chronic stress procedure to replicate the situation of animals under chronic stress. Histological and immunohistochemical analyses were performed focusing on kisspeptin neurons in the arcuate hypothalamic nucleus (ARC) and DNA fragmented cells in seminiferous tubules. Although the ARC was not morphologically altered in either the stressed or non-stressed group, granular kisspeptin immunoreactivities decreased slightly in the stress group. In the testes of the stress group, several signs of testicular degeneration were observed, including increased numbers of ssDNA-positive cells per seminiferous tubule, thinning, vacuoled seminiferous epithelia and multinucleated giant cells. The decreases in kisspeptin in the stress group might be due to other hypothalamic peptides, such as corticotropin-releasing hormone and leptin, whose receptors are known to coexpress in the ARC. In addition, environmental stress directly and indirectly affects testicular function through stress hormones and gonadotropins. In summary, our findings enhance the understanding of stress-induced reproductive suppression possibly mediated by kisspeptin in the ARC.

Show MeSH

Related in: MedlinePlus

Effect of unpredictable chronic stress on absolute weights of brain and testes at 4weeks. (A) The average testis weight of the stress group was significantly lower thanthat of the control group. (B) There was no significant difference between brainweights of both groups. Values are presented as the mean ± SD (n=6 mice each).**P<0.01.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4197145&req=5

fig_002: Effect of unpredictable chronic stress on absolute weights of brain and testes at 4weeks. (A) The average testis weight of the stress group was significantly lower thanthat of the control group. (B) There was no significant difference between brainweights of both groups. Values are presented as the mean ± SD (n=6 mice each).**P<0.01.

Mentions: Unpredictable chronic stress suppressed the body weight gain of the mice. All micegained weight gradually throughout the 4 weeks experimental period, but there weresignificant differences between the body weights of the control and stress groups at 3weeks and 4 weeks. Values are presented as the mean ± SD (n=6 mice each).*P<0.05; **P<0.01.


Unpredictable chronic stress-induced reproductive suppression associated with the decrease of kisspeptin immunoreactivity in male mice.

Hirano T, Kobayashi Y, Omotehara T, Tatsumi A, Hashimoto R, Umemura Y, Nagahara D, Mantani Y, Yokoyama T, Kitagawa H, Hoshi N - J. Vet. Med. Sci. (2014)

Effect of unpredictable chronic stress on absolute weights of brain and testes at 4weeks. (A) The average testis weight of the stress group was significantly lower thanthat of the control group. (B) There was no significant difference between brainweights of both groups. Values are presented as the mean ± SD (n=6 mice each).**P<0.01.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4197145&req=5

fig_002: Effect of unpredictable chronic stress on absolute weights of brain and testes at 4weeks. (A) The average testis weight of the stress group was significantly lower thanthat of the control group. (B) There was no significant difference between brainweights of both groups. Values are presented as the mean ± SD (n=6 mice each).**P<0.01.
Mentions: Unpredictable chronic stress suppressed the body weight gain of the mice. All micegained weight gradually throughout the 4 weeks experimental period, but there weresignificant differences between the body weights of the control and stress groups at 3weeks and 4 weeks. Values are presented as the mean ± SD (n=6 mice each).*P<0.05; **P<0.01.

Bottom Line: Although the ARC was not morphologically altered in either the stressed or non-stressed group, granular kisspeptin immunoreactivities decreased slightly in the stress group.The decreases in kisspeptin in the stress group might be due to other hypothalamic peptides, such as corticotropin-releasing hormone and leptin, whose receptors are known to coexpress in the ARC.In addition, environmental stress directly and indirectly affects testicular function through stress hormones and gonadotropins.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Molecular Morphology, Department of Animal Science, Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.

ABSTRACT
Environmental stress affects various parts of mammals typically through the circulation of stress hormones. It has been identified as one of the possible reasons for male reproductive difficulties, but the complex mechanisms responsible for stress-induced reproductive suppression are poorly understood. Here, we examined the relationship between chronic environmental stress and hypothalamic kisspeptin, a recently discovered upstream regulator of the reproductive endocrine feedback system. We studied male mice under an unpredictable chronic stress procedure to replicate the situation of animals under chronic stress. Histological and immunohistochemical analyses were performed focusing on kisspeptin neurons in the arcuate hypothalamic nucleus (ARC) and DNA fragmented cells in seminiferous tubules. Although the ARC was not morphologically altered in either the stressed or non-stressed group, granular kisspeptin immunoreactivities decreased slightly in the stress group. In the testes of the stress group, several signs of testicular degeneration were observed, including increased numbers of ssDNA-positive cells per seminiferous tubule, thinning, vacuoled seminiferous epithelia and multinucleated giant cells. The decreases in kisspeptin in the stress group might be due to other hypothalamic peptides, such as corticotropin-releasing hormone and leptin, whose receptors are known to coexpress in the ARC. In addition, environmental stress directly and indirectly affects testicular function through stress hormones and gonadotropins. In summary, our findings enhance the understanding of stress-induced reproductive suppression possibly mediated by kisspeptin in the ARC.

Show MeSH
Related in: MedlinePlus