Article

Intermittent Fasting Dietary Restriction Regimen Negatively Influences Reproduction in Young Rats: A Study of Hypothalamo-Hypophysial-Gonadal Axis

Department of Biotechnology, Guru Nanak Dev University, Amritsar, Punjab, India.
PLoS ONE (Impact Factor: 3.53). 01/2013; 8(1):e52416. DOI: 10.1371/journal.pone.0052416
Source: PubMed

ABSTRACT Nutritional infertility is very common in societies where women fail to eat enough to match their energy expenditure and such females often present as clinical cases of anorexia nervosa. The cellular and molecular mechanisms that link energy balance and central regulation of reproduction are still not well understood. Peripheral hormones such as estradiol, testosterone and leptin, as well as neuropeptides like kisspeptin and neuropeptides Y (NPY) play a potential role in regulation of reproduction and energy balance with their primary target converging on the hypothalamic median eminence-arcuate region. The present study was aimed to explore the effects of negative energy state resulting from intermittent fasting dietary restriction (IF-DR) regimen on complete hypothalamo-hypophysial-gonadal axis in Wistar strain young female and male rats. Significant changes in body weight, blood glucose, estrous cyclicity and serum estradiol, testosterone and LH level indicated the negative role of IF-DR regimen on reproduction in these young animals. Further, it was elucidated whether serum level of metabolic hormone, leptin plays a mechanistic role in suppressing hypothalamo-hypophysial-gonadal (HPG) axis via energy regulators, kisspeptin and NPY in rats on IF-DR regimen. We also studied the effect of IF-DR regimen on structural remodeling of GnRH axon terminals in median eminence region of hypothalamus along with the glial cell marker, GFAP and neuronal plasticity marker, PSA-NCAM using immunostaining, Western blotting and RT-PCR. Together these data suggest that IF-DR regimen negatively influences reproduction in young animals due to its adverse effects on complete hypothalamus-hypophysial-gonadal axis and may explain underlying mechanism(s) to understand the clinical basis of nutritional infertility.

0 Followers
 · 
127 Views
  • Source
    • "Specifically, CR increased the density of NPY-ir material across the rostrocaudal extent of the ARC in vehicle-injected mice, and in all but the most rostral ARC level in LPS-injected mice. This is consistent with previous studies reporting CR-induced enhancement of ARC levels of NPY mRNA expression (Brady et al., 1990; McShane et al., 1999; Shimokawa et al., 2003; Johnstone et al., 2005), NPY protein (Lewis et al., 1993), and NPY-immunolabeling (Abizaid et al., 1997; Kurose et al., 2005; Kumar and Kaur, 2013). Similarly, our laboratory previously found that hypothalamic NPY Fig. 4. Calorie restriction reduced the total area of Iba1-positive microglial cells in the arcuate hypothalamic nucleus (ARC). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Calorie restriction (CR) increases longevity and elicits many health promoting benefits including delaying immunosenescence and reducing the incidence of age-related diseases. Although the mechanisms underlying the health-enhancing effects of CR are not known, a likely contributing factor is alterations in immune system functioning. CR suppresses lipopolysaccharide (LPS)-induced release of pro-inflammatory cytokines, blocks LPS-induced fever, and shifts hypothalamic signaling pathways to an anti-inflammatory bias. Furthermore, we have recently shown that CR attenuates LPS-stimulated microglial activation in the hypothalamic arcuate nucleus (ARC), a brain region containing neurons that synthesize neuropeptide Y (NPY), an orexigenic neuropeptide that is upregulated by a CR diet and has anti-inflammatory properties. To determine if increased NPY expression in the ARC following CR was associated with changes in microglial activation, a set of brain sections from mice that were exposed to 50% CR or ad libitum feeding for 28days before being injected with LPS were immunostained for NPY. The density of NPY-immunolabeling was assessed across the rostrocaudal extent of the ARC and hypothalamic paraventricular nucleus (PVN). An adjacent set of sections were immunostained for ionized calcium-binding adapter molecule-1 (Iba1) and immunostained microglia in the ARC were digitally reconstructed to investigate the effects of CR on microglial morphology. We demonstrated that exposure to CR increased NPY expression in the ARC, but not the PVN. Digital reconstruction of microglia revealed that LPS increased Iba1 intensity in ad libitum fed mice but had no effect on Iba1 intensity in CR mice. CR also decreased the size of ARC microglial cells following LPS. Correlational analyses revealed strong associations between NPY and body temperature, and body temperature and microglia area. Together these results suggest that CR-induced changes in NPY are not directly involved in the suppression of LPS-induced microglial activation, however, NPY may indirectly affect microglial morphology through changes in body temperature. Copyright © 2014. Published by Elsevier Ltd.
    Neuroscience 11/2014; 285. DOI:10.1016/j.neuroscience.2014.11.014 · 3.33 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hypothalamic-pituitary-adrenal axis impairment in anorexia nervosa is marked by hypercortisolemia, and psychiatric disorders occur in the majority of patients with Cushing's syndrome. Here we report a patient diagnosed with anorexia nervosa who also developed Cushing's syndrome. A 26-year-old female had been treated for anorexia nervosa since she was 17 years old, and also developed depression and paranoid schizophrenia. She was admitted to the Department of Endocrinology, Metabolism, and Internal Medicine with a preliminary diagnosis of Cushing's syndrome. Computed tomography revealed a 27 mm left adrenal tumor, and she underwent laparoscopic adrenalectomy. She was admitted to hospital 6 months after this procedure, at which time she did not report any eating or mood disorder. This is a rare case report of a patient with anorexia nervosa in whom Cushing's syndrome was subsequently diagnosed. Diagnostic difficulties were caused by the signs and symptoms presenting in the course of both disorders, ie, hypercortisolemia, osteoporosis, secondary amenorrhea, striae, hypokalemia, muscle weakness, and depression.
    Neuropsychiatric Disease and Treatment 03/2013; 9:431-5. DOI:10.2147/NDT.S40398 · 2.15 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The placenta produces a number of signaling molecules including metabolic and reproductive hormones as well as several inflammatory mediators. Among them, Interleukin-6 (IL-6), a well-known immune and metabolic regulator, acts peripherally modulating metabolic function and centrally increasing energy expenditure and reducing body fat. IL-6 interacts with key hypothalamic neuropeptidergic systems controlling energy homeostasis such as those producing the orexigenic/anabolic: neuropeptide Y (NPY) and agouti-related peptide (AgRP) and anorectic/catabolic neuropeptides: proopiomelanocortin (POMC) and cocaine and amphetamine regulated transcript (CART). Human and rat placenta have been identified as source of these neuropeptides, but their expression and regulation in murine placental tissues remain unknown. Therefore, placental mRNA levels of IL-6, NPY, AgRP, POMC, and CART at different pregnancy stages (gestational days 13, 15, and 18) were analyzed by real time PCR, as were the effect of IL-6 deficiency (IL-6 knockout mice) on their placental expression. Our results showed that placenta-derived neuropeptides were regulated by gestational age and IL-6 throughout the second half of mouse pregnancy. These data suggest that IL-6 may participate in the fine tune control of energy balance during pregnancy by extending its action as a metabolic signal to the main organ at the fetomaternal interface: the placenta.
    International Journal of Endocrinology 03/2014; 2014:537603. DOI:10.1155/2014/537603 · 1.52 Impact Factor
Show more

Preview (2 Sources)

Download
4 Downloads
Available from