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Cell Reports Aug 2021Enhanced appetite occurs as a means of behavioral thermoregulation at low temperature. Neural circuitry mediating this crosstalk between behavioral thermoregulation and...
Enhanced appetite occurs as a means of behavioral thermoregulation at low temperature. Neural circuitry mediating this crosstalk between behavioral thermoregulation and energy homeostasis remains to be elucidated. We find that the hypothalamic orexigenic agouti-related neuropeptide (AgRP) neurons in the arcuate nucleus (ARC) are profoundly activated by cold exposure. The calcium signals in ARC neurons display an immediate-response pattern in response to cold stimulation. Cold-responsive neurons in the medial preoptic area (mPOA) make excitatory synapses onto ARC neurons. Inhibition of either ARC neurons or ARC-projecting mPOA neurons attenuates cold-evoked feeding, while activation of the mPOA-to-ARC projection increases food intake. These findings reveal an mPOA-ARC neural pathway that modulates cold-evoked feeding behavior.
Topics: Agouti-Related Protein; Animals; Arcuate Nucleus of Hypothalamus; Cold Temperature; Feeding Behavior; Mice, Inbred C57BL; Neural Pathways; Neurons; Preoptic Area; Synapses; Mice
PubMed: 34380037
DOI: 10.1016/j.celrep.2021.109502 -
Physiology & Behavior May 2021The neural system underlying maternal caregiving has often been studied using laboratory rodents and a few other mammalian species. This research shows that the medial...
The neural system underlying maternal caregiving has often been studied using laboratory rodents and a few other mammalian species. This research shows that the medial preoptic area (mPOA) integrates sensory cues from the young that, along with hormonal and other environmental signals, control maternal acceptance of neonates. The mPOA then activates the mesolimbic system to drive maternal motivation and caregiving activities. How components of this neural system respond to maternal experience and exposure to young in non-mammals has rarely been examined. To gain more insight into this question, virgin female Japanese quail (Coturnix japonica) were induced to be maternal through four days of continuous exposure to chicks (Maternal), or were not exposed to chicks (Non-Maternal). Chicks were removed overnight from the Maternal group and half the females from each group were then exposed to chicks for 90 minutes (Exposed), or not exposed to chicks (Non-Exposed), before euthanasia. The number of Fos-immunoreactive (Fos-ir) cells was examined as a marker of neuronal activation. As expected, repeated exposure to chicks induced caregiving behavior in the Maternal females, which persisted after the overnight separation, suggesting the formation of a maternal memory. In contrast, Non-Maternal females were aggressive and rejected the chicks when exposed to them. Exposed females, whether or not they were given prior experience with chicks (i.e., regardless if they accepted or rejected chicks during the exposure before euthanasia), had more Fos-ir cells in the mPOA compared to Non-Exposed females. In the nucleus accumbens (NAC), the number of Fos-ir cells was high in all Maternal females whether or not they were Exposed to chicks again before euthanasia. In the lateral bed nucleus of the stria terminalis, a site involved in general stress responding, groups did not differ in the number of Fos-ir cells. These data indicate a conserved role for the mPOA and NAC in maternal caregiving across vertebrates, with the mPOA acutely responding to the salience rather than valence of offspring cues, and the NAC showing longer-term changes in activity after a positive maternal experience even without a recent exposure to young.
Topics: Animals; Coturnix; Female; Humans; Infant, Newborn; Maternal Behavior; Nucleus Accumbens; Preoptic Area; Proto-Oncogene Proteins c-fos
PubMed: 33582165
DOI: 10.1016/j.physbeh.2021.113357 -
Ageing Research Reviews Jan 2010Temperature is an important modulator of longevity and aging in both poikilotherms and homeotherm animals. In homeotherms, temperature homeostasis is regulated primarily... (Review)
Review
Temperature is an important modulator of longevity and aging in both poikilotherms and homeotherm animals. In homeotherms, temperature homeostasis is regulated primarily in the preoptic area (POA) of the hypothalamus. This region receives and integrates peripheral, central and environmental signals and maintains a nearly constant core body temperature (T(core)) by regulating the autonomic and hormonal control of heat production and heat dissipation. Temperature sensitive neurons found in the POA are considered key elements of the neuronal circuitry modulating these effects. Nutrient homeostasis is also a hypothalamically regulated modulator of aging as well as one of the signals that can influence T(core) in homeotherms. Investigating the mechanisms of the regulation of nutrient and temperature homeostasis in the hypothalamus is important to understanding how these two elements of energy homeostasis influence longevity and aging as well as how aging can affect hypothalamic homeostatic mechanisms.
Topics: Animals; Body Temperature Regulation; Caloric Restriction; Female; Fever; Homeostasis; Humans; Longevity; Male; Mice; Neurons; Preoptic Area; Rats; Shivering; Skin
PubMed: 19631766
DOI: 10.1016/j.arr.2009.07.004 -
Nature Communications Nov 2022Therapeutic hypothermia at 32-34 °C during or after cerebral ischaemia is neuroprotective. However, peripheral cold sensor-triggered hypothermia is ineffective and...
Therapeutic hypothermia at 32-34 °C during or after cerebral ischaemia is neuroprotective. However, peripheral cold sensor-triggered hypothermia is ineffective and evokes vigorous counteractive shivering thermogenesis and complications that are difficult to tolerate in awake patients. Here, we show in mice that deep brain stimulation (DBS) of warm-sensitive neurones (WSNs) in the medial preoptic nucleus (MPN) produces tolerable hypothermia. In contrast to surface cooling-evoked hypothermia, DBS mice exhibit a torpor-like state without counteractive shivering. Like hypothermia evoked by chemogenetic activation of WSNs, DBS in free-moving mice elicits a rapid lowering of the core body temperature to 32-34 °C, which confers significant brain protection and motor function reservation. Mechanistically, activation of WSNs contributes to DBS-evoked hypothermia. Inhibition of WSNs prevents DBS-evoked hypothermia. Maintaining the core body temperature at normothermia during DBS abolishes DBS-mediated brain protection. Thus, the MPN is a DBS target to evoke tolerable therapeutic hypothermia for stroke treatment.
Topics: Animals; Mice; Hypothermia; Preoptic Area; Shivering; Brain; Disease Models, Animal; Ischemia
PubMed: 36371436
DOI: 10.1038/s41467-022-34735-2 -
The Journal of Physiological Sciences :... Jun 2024Hibernation and torpor are not passive responses caused by external temperature drops and fasting but are active brain functions that lower body temperature. A...
Hibernation and torpor are not passive responses caused by external temperature drops and fasting but are active brain functions that lower body temperature. A population of neurons in the preoptic area was recently identified as such active torpor-regulating neurons. We hypothesized that the other hypothermia-inducing maneuvers would also activate these neurons. To test our hypothesis, we first refined the previous observations, examined the brain regions explicitly activated during the falling phase of body temperature using c-Fos expression, and confirmed the preoptic area. Next, we observed long-lasting hypothermia by reactivating torpor-tagged Gq-expressing neurons using the activity tagging and DREADD systems. Finally, we found that about 40-60% of torpor-tagged neurons were activated by succeeding isoflurane anesthesia and by icv administration of an adenosine A1 agonist. Isoflurane-induced and central adenosine-induced hypothermia is, at least in part, an active process mediated by the torpor-regulating neurons in the preoptic area.
Topics: Animals; Preoptic Area; Isoflurane; Adenosine; Neurons; Male; Anesthetics, Inhalation; Body Temperature; Hypothermia; Torpor; Mice; Proto-Oncogene Proteins c-fos
PubMed: 38867187
DOI: 10.1186/s12576-024-00927-2 -
The Journal of Experimental Biology Sep 2020Social preferences enable animals to selectively interact with some individuals over others. One influential idea for the evolution of social preferences is that...
Social preferences enable animals to selectively interact with some individuals over others. One influential idea for the evolution of social preferences is that preferred signals evolve because they elicit greater neural responses from sensory systems. However, in juvenile plains spadefoot toad (), a species with condition-dependent mating preferences, responses of the preoptic area, but not of the auditory midbrain, mirror adult social preferences. To examine whether this separation of signal representation from signal valuation generalizes to other anurans, we compared the relative contributions of noradrenergic signalling in the preoptic area and auditory midbrain of and its close relative We manipulated body condition in juvenile toads by controlling diet and used high pressure liquid chromatography to compare call-induced levels of noradrenaline and its metabolite MHPG in the auditory midbrain and preoptic area of the two species. We found that calls from the two species induced different levels of noradrenaline and MHPG in the auditory system, with higher levels measured in both species for the more energetic call. In contrast, noradrenaline levels in the preoptic area mirrored patterns of social preferences in both and That is, noradrenaline levels were higher in response to the preferred calls within each species and were modified by diet in (with condition-dependent preferences) but not (with condition-independent preferences). Our results are consistent with a potentially important role for preoptic noradrenaline in the development of social preferences and indicate that it could be a target of selection in the evolution of condition-dependent social preferences.
Topics: Animals; Anura; Bufonidae; Norepinephrine; Preoptic Area; Reproduction
PubMed: 32647019
DOI: 10.1242/jeb.214148 -
The Journal of Neuroscience : the... Mar 2006The median preoptic nucleus (MnPN) and the ventral lateral preoptic area (vlPOA) of the hypothalamus express sleep-related Fos immunoreactivity, and a subset of... (Comparative Study)
Comparative Study
The median preoptic nucleus (MnPN) and the ventral lateral preoptic area (vlPOA) of the hypothalamus express sleep-related Fos immunoreactivity, and a subset of Fos-immunoreactive neurons (IRNs) in these nuclei contain glutamic acid decarboxylase (GAD), a marker of GABAergic cells. We recently showed that the numbers of Fos-positive (Fos+) and Fos+ GAD-IRNs in both the MnPN and the vlPOA are positively correlated with the total amount of preceding sleep. The present study was designed to clarify whether or not activation of sleep-related neurons in the rat MnPN and vlPOA is associated with rapid eye movement (REM) sleep regulation. Expression of c-fos in MnPN and vlPOA neurons was examined under conditions of spontaneous sleep, REM sleep restriction, and REM sleep recovery after REM sleep restriction. Across all conditions, the number of Fos-IRNs was highest in REM-sleep-restricted rats displaying the highest levels of REM sleep homeostatic pressure/drive, i.e., those rats exhibiting the most frequent attempts to enter REM sleep. This finding provides the first evidence that activation of subsets of MnPN and vlPOA neurons is more strongly related to REM sleep pressure than to REM sleep amount.
Topics: Animals; Biomarkers; Electroencephalography; Genes, fos; Glutamate Decarboxylase; Homeostasis; Isoenzymes; Male; Nerve Tissue Proteins; Neurons; Preoptic Area; Proto-Oncogene Proteins c-fos; Rats; Rats, Sprague-Dawley; Sleep Deprivation; Sleep, REM; Wakefulness; gamma-Aminobutyric Acid
PubMed: 16540582
DOI: 10.1523/JNEUROSCI.4827-05.2006 -
Acta Physiologica (Oxford, England) Apr 2019To determine the role of neurons in the ventral part of the lateral preoptic area (vLPO) in CNS thermoregulation.
AIM
To determine the role of neurons in the ventral part of the lateral preoptic area (vLPO) in CNS thermoregulation.
METHODS
In vivo electrophysiological and neuropharmacological were used to evaluate the contribution of neurons in the vLPO to the regulation of brown adipose tissue (BAT) thermogenesis and muscle shivering in urethane/chloralose-anaesthetized rats.
RESULTS
Nanoinjections of NMDA targeting the medial preoptic area (MPA) and the vLPO suppressed the cold-evoked BAT sympathetic activity (SNA), reduced the BAT temperature (T ), expired CO , mean arterial pressure (MAP), and heart rate. Inhibition of vLPO neurons with muscimol or AP5/CNQX elicited increases in BAT SNA, T , tachycardia, and small elevations in MAP. The BAT thermogenesis evoked by AP5/CNQX in vLPO was inhibited by the activation of MPA neurons. The inhibition of BAT SNA by vLPO neurons does not require a GABAergic input to dorsomedial hypothalamus (DMH), but MPA provides a GABAergic input to DMH. The activation of vLPO neurons inhibits the BAT thermogenesis evoked by NMDA in the rostral raphe pallidus (rRPa), but not that after bicuculline in rRPa. The BAT thermogenesis elicited by vLPO inhibition is dependent on glutamatergic inputs to DMH and rRPa, but these excitatory inputs do not arise from MnPO neurons. The activation of neurons in the vLPO also inhibits cold- and prostaglandin-evoked muscle shivering, and vLPO inhibition is sufficient to evoke shivering.
CONCLUSION
The vLPO contains neurons that are required for the warm ambient-evoked inhibition of muscle shivering and of BAT thermogenesis, mediated through a direct or indirect GABAergic input to rRPa from vLPO.
Topics: Adipose Tissue, Brown; Animals; Dinoprostone; Male; N-Methylaspartate; Nucleus Raphe Pallidus; Preoptic Area; Rats, Sprague-Dawley; Receptors, GABA; Receptors, Glutamate; Shivering
PubMed: 30365209
DOI: 10.1111/apha.13213 -
Brain Research May 2019Normal glucose homeostasis depends on the capacity of pancreatic β-cells to adjust insulin secretion in response to a change of tissue insulin sensitivity. In cold...
Normal glucose homeostasis depends on the capacity of pancreatic β-cells to adjust insulin secretion in response to a change of tissue insulin sensitivity. In cold environments, for example, the dramatic increase of insulin sensitivity required to ensure a sufficient supply of glucose to thermogenic tissues is offset by a proportionate reduction of insulin secretion, such that overall glucose tolerance is preserved. That these cold-induced changes of insulin secretion and insulin sensitivity are dependent on sympathetic nervous system (SNS) outflow suggests a key role for thermoregulatory neurons in the hypothalamic preoptic area (POA) in this metabolic response. As these POA neurons are themselves sensitive to changes in local hypothalamic temperature, we hypothesized that direct cooling of the POA would elicit the same glucoregulatory responses that we observed during cold exposure. To test this hypothesis, we used a thermode to cool the POA area, and found that as predicted, short-term (8-h) intense POA cooling reduced glucose-stimulated insulin secretion (GSIS), yet glucose tolerance remained unchanged due to an increase of insulin sensitivity. Longer-term (24-h), more moderate POA cooling, however, failed to inhibit GSIS and improved glucose tolerance, an effect associated with hyperthermia and activation of the hypothalamic-pituitary-adrenal axis, indicative of a stress response. Taken together, these findings suggest that POA cooling is sufficient to recapitulate key glucoregulatory responses to cold exposure.
Topics: Animals; Blood Glucose; Body Temperature Regulation; Glucose; Homeostasis; Insulin; Insulin Resistance; Male; Neurons; Preoptic Area; Rats, Wistar
PubMed: 30610874
DOI: 10.1016/j.brainres.2019.01.002 -
Neurochemical Research Oct 2019The behavior of female rats changes profoundly as they become mothers. The brain region that plays a central role in this regulation is the preoptic area, and lesions in...
The behavior of female rats changes profoundly as they become mothers. The brain region that plays a central role in this regulation is the preoptic area, and lesions in this area eliminates maternal behaviors in rodents. The molecular background of the behavioral changes has not been established yet; therefore, in the present study, we applied proteomics to compare protein level changes associated with maternal care in the rat preoptic area. Using 2-dimensional fluorescence gel electrophoresis followed by identification of altered spots with mass spectrometry, 12 proteins were found to be significantly increased, and 6 proteins showed a significantly reduced level in mothers. These results show some similarities with a previous proteomics study of the maternal medial prefrontal cortex and genomics approaches applied to the preoptic area. Gene ontological analysis suggested that most altered proteins are involved in glucose metabolism and neuroplasticity. These proteins may support the maintenance of increased neuronal activity in the preoptic area, and morphological changes in preoptic neuronal circuits are known to take place in mothers. An increase in the level of alpha-crystallin B chain (Cryab) was confirmed by Western blotting. This small heat shock protein may also contribute to maintaining the increased activity of preoptic neurons by stabilizing protein structures. Common regulator and target analysis of the altered proteins suggested a role of prolactin in the molecular changes in the preoptic area. These results first identified the protein level changes in the maternal preoptic area. The altered proteins contribute to the maintenance of maternal behaviors and may also be relevant to postpartum depression, which can occur as a molecular level maladaptation to motherhood.
Topics: Animals; Behavior, Animal; Electrophoresis, Gel, Two-Dimensional; Female; Maternal Behavior; Neurons; Prefrontal Cortex; Preoptic Area; Proteomics; Rats
PubMed: 30847857
DOI: 10.1007/s11064-019-02755-y