Thermoregulatory disorder

Physiology

• Thermoregulation is a vital function of autonomic nervous system in response to cold and heat stress.
• Thermoregulatory physiology sustains health by keeping body core temperature within a degree or two of 37°C, which enables normal cellular function.
• Heat production and dissipation are dependent on a coordinated set of autonomic responses.
• Thermoregulatory pathways include autonomic neuropathies and ganglionopathies.

Thermostat

• Hypothalamus is body thermostat, which contains temperature sensors. These cells are connected to nerve cells called thermoreceptors.
• There are two types of thermoreceptors, colds and warms
• Thermoreceptors are scattered throughout the body in order to provide useful information to the hypothalamus

Related diseases

• Menopausal hot flashes. thought to be a disorder of thermoregulation initiated centrally within the medial preoptic area of the hypothalamus. The central thermoregulatory mechanism underlying hot flashes may affect hypnogenic pathways inducing sleep and heat loss in the absence of a thermal load.

• Hyperthermia occurs when the body’s heat-regulating mechanisms fail, and the body temperature becomes too high.

• Hypothermia occurs when the body loses heat faster than it can produce it. Prolonged exposure to cold temperatures can cause hypothermia.
• Infections: Pathogens can thrive at typical body temperatures, but an increased temperature makes it more difficult for some of them to survive.
• Endocrine disorders: The endocrine system comprises glands and organs that produce hormones, such as the pancreas, thyroid, pituitary gland, and adrenal glands. If something interferes with hormone production, it can affect body temperature.
• Hypothyroidism, can lead to a lower body temperature, while an overactive thyroid, called hyperthyroidism, can cause a higher body temperature.

CNS disorders

• Brain injuries / tumors
• Spinal cord injuries
• Parkinson disease
• MS

Sleep and Thermoregulation

• Sleep and body temperature are tightly interconnected in mammals
• Warming up our body helps to fall asleep and the body temperature in turn drops while falling asleep.
• Preoptic area of the hypothalamus (POA) serves as an essential brain region to coordinate sleep and body temperature
• In the 1920s, lesions in the POA were found to be associated with insomnia in human patients affected by encephalitis lethargica

• Studies suggest a critical role of the POA in integrating temperature information and triggering behavioral and autonomic responses through their central and peripheral downstream targets to adjust the body temperature
• Different types of sleep disorders, especially those associated with aging, may be influenced by altered body temperature rhythms or dysregulation of vasodilation resulting in an impairment to prepare the body for sleep
• Dysfunctions in sensing and transferring temperature information to the neurons controlling sleep within the POA may contribute to attenuate the sleep onset in the elderly. Elucidating how POA neurons receiving peripheral temperature signals interact with the sleep-promoting neurons and integrate circadian rhythms, and how these circuits become dysfunctional with aging will greatly improve our current therapeutics for sleep disorders.