Hyperleptinemia in Pregnant Bats Is Characterized by Increased Placental Leptin Secretion In Vitro

Kronfeld‐Schor, Noga; Zhao, Jing; Silvia, Brian A.; Mathews, Patrick T.; Zimmerman, Stefan L.; Widmaier, Eric P.; Kunz, Thomas

doi:10.1385/endo:14:2:225

Cited by 12 publications

(19 citation statements)

References 35 publications

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“…All mammals thus far investigated, including humans, showed increased serum leptin level during mid-to late-pregnancy (Gavrilova et al 1997, Masuzaki et al 1997, Kunz et al 1999, Zhao et al 2003. Contrary to the non-pregnant mammals, elevated leptin levels of pregnancy in mammals are not usually correlated with adiposity (Kronfeld-Schor et al 2001). In baboons, bats, and humans, the placenta is a major source of circulating leptin level during pregnancy (Hoggard et al 2000, Kronfeld-Schor et al 2001.…”

Section: Role Of Leptin In Bat Ovarymentioning

confidence: 99%

“…Contrary to the non-pregnant mammals, elevated leptin levels of pregnancy in mammals are not usually correlated with adiposity (Kronfeld-Schor et al 2001). In baboons, bats, and humans, the placenta is a major source of circulating leptin level during pregnancy (Hoggard et al 2000, Kronfeld-Schor et al 2001. The conservation of hyperleptinemia during pregnancy across mammalian orders implies a fundamental role of leptin either in the maintenance of pregnancy or preparation for lactation (Kronfeld-Schor et al 2000).…”

Section: Role Of Leptin In Bat Ovarymentioning

confidence: 99%

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Adiposity associated rise in leptin impairs ovarian activity during winter dormancy in Vespertilionid bat, Scotophilus heathi

Srivastava¹,

Krishna²

2007

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The aim of the study was to evaluate the seasonal variation in serum leptin levels in a natural population of the female bat, Scotophilus heathi and their relationship to the changes in the body mass, serum insulin level, and ovarian activity. Circulating leptin level varied significantly over the season and correlated positively with the changes in body mass, and circulating insulin and androstenedione (A4) levels. Circulating leptin concentrations showed two peaks; one coincides with the maximum fat accumulation prior to winter dormancy, whereas the second shorter peak coincides with late pregnancy. The in vivo study in S. heathi showed that the increased circulating leptin level during winter dormancy coincides with the decreased expression of ovarian steroidogenic acute regulatory (StAR) protein, and low circulating estradiol (E 2 ) level. At the same time, increased circulating leptin level coincides with increased expression of ovarian insulin receptor and high circulating A4 level. The low circulating leptin level during preovulatory period coincides with the increase in StAR protein but decrease in insulin receptor protein. The in vitro study confirmed the in vivo observations of inhibitory effect of leptin on LH induced StAR expression and E 2 production, whereas the stimulatory effect of leptin (high dose) on LH induced expression of insulin receptor protein and A4 production. However, pharmacological dose of leptin produced inhibitory effect on the expression of insulin receptor protein.The results of the present study thus suggest that high circulating leptin level during winter dormancy promotes adiposity and impairs ovarian activity by suppressing StAR-mediated E 2 production as well as by enhancing insulin receptor-mediated A4 synthesis thereby contributing anovulatory condition of delayed ovulation in S. heathi.

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Section: Role Of Leptin In Bat Ovarymentioning

confidence: 99%

Section: Role Of Leptin In Bat Ovarymentioning

confidence: 99%

Adiposity associated rise in leptin impairs ovarian activity during winter dormancy in Vespertilionid bat, Scotophilus heathi

Srivastava¹,

Krishna²

2007

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“…Serum leptin concentrations increase dramatically during pregnancy in every mammalian species studied thus far [3,24,25,26,27]. This is due in part to high concentrations of estrogen, which stimulates leptin production.…”

Section: Introductionmentioning

confidence: 99%

The source of leptin, but not leptin depletion in response to food restriction, changes during early pregnancy in mice

Schlitt

Schulz

2011

Endocrine

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Maternal food restriction during pregnancy results in adverse consequences for offspring, including obesity and cardiovascular disease. Early pregnancy is a critical period for this programming effect. Leptin is a regulator of energy homeostasis that also affects placental and fetal development. As food restriction results in decreased serum leptin levels, at least in non-pregnant animals, leptin depletion may be one mechanism by which food restriction affects development. The goal of this study was to test whether moderate food restriction affects serum leptin concentrations during the first half of pregnancy. We found that restriction to 50% of ad libitum consumption levels resulted in a significant decrease in serum leptin concentrations in both pregnant and non-pregnant female mice. There was no significant difference in serum leptin concentrations between non-pregnant females and at pregnancy day 11.5 when fed ad libitum. However, there was a difference in the source of leptin during pregnancy, with greater production in visceral fat in pregnant mice, and greater production in subcutaneous fat in non-pregnant mice. Leptin concentrations were dependent on time of day and time of sampling relative to feeding, particularly in restricted mice. There was a significant difference in serum leptin concentrations between fed and restricted mice when they were fed and sampled in afternoon, but not when they were fed and sampled in morning. We conclude that food restriction results in a significant decrease in leptin concentration during the first half of pregnancy in mice, but that detection of this relationship is subject to experimental design considerations.

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“…It was found that peripheral signals of the energetic state, with leptin concentration as the main indicator, provide the brain with information that translates to neuropeptide expression levels that, in turn, control the response to the energetic state (even though there are many examples of disassociation between plasma leptin concentrations and body mass, body fat, and energetic state, e.g., Refs. [33][34][35]. One of the major sites of leptin activity in the brain is the arcuate nucleus of the hypothalamus, where orexigenic neuropeptides such as neuropeptide Y (NPY) and agouti-related protein (AgRP), and the anorexigenic proopiomelanocortin (POMC) and cocaine and amphetaminerelated transcript (CART) expression levels change in response to information from the periphery [reviewed by Schwartz et al (52)].…”

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confidence: 99%

Effect of food availability and leptin on the physiology and hypothalamic gene expression of the golden spiny mouse: a desert rodent that does not hoard food

Gutman

Hacmon-Keren²,

Choshniak³

et al. 2008

American Journal of Physiology-Regulatory, Integrative and Comp

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Food availability and quality in desert habitats are spatially and temporally unpredictable, and animals face periods of food shortage. The golden spiny mouse (Acomys russatus) is an omnivorous desert rodent that does not hoard food, requiring it to withstand such periods by physiological means alone. In response to food restriction, plasma leptin concentrations, core body temperature, and energy expenditure of the spiny mouse decrease significantly after 24 h, and most spiny mice are able to maintain their body mass to approximately 85% of ad libitum for a prolonged period of time. Both 1-day food deprivation and long-term food restriction had a significant effect on body mass and plasma leptin concentrations, which decreased significantly with a high correlation, as well as on the orexigenic agouti-related protein, which increased significantly as a result of the 24-h food deprivation; and on neuropeptide Y (NPY), in which the increase was more pronounced under long-term food restriction. Food restriction and food deprivation had no effect, however, on the anorexigenic pro-opiomelanocortin and cocaine and amphetamine-related transcript. Leptin administration to food-restricted spiny mice did not affect food intake or the rate of decrease in body mass, indicating that it cannot overcome the drive to eat when food is scarce. However, it did result in a significant decrease in NPY levels, and the spiny mice spent less time at low body temperatures compared with PBS-treated golden spiny mice. These results show that in food-restricted golden spiny mice, leptin affects thermogenesis, but not food consumption, and suggest that the thermoregulatory effects of leptin are mediated by NPY.

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Hyperleptinemia in Pregnant Bats Is Characterized by Increased Placental Leptin Secretion In Vitro

Cited by 12 publications

References 35 publications

Adiposity associated rise in leptin impairs ovarian activity during winter dormancy in Vespertilionid bat, Scotophilus heathi

Adiposity associated rise in leptin impairs ovarian activity during winter dormancy in Vespertilionid bat, Scotophilus heathi

The source of leptin, but not leptin depletion in response to food restriction, changes during early pregnancy in mice

Effect of food availability and leptin on the physiology and hypothalamic gene expression of the golden spiny mouse: a desert rodent that does not hoard food

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