If you are old enough, you may recall that the pineal gland received a great deal of quite unscientific attention from the early life extension community, decades ago, overlapping to some degree with its association in lineages of mystical thinking with the third eye. We live in a strange world populated by strange people. Scientifically, the pineal gland is a fairly important part of the endocrine system, and like all organs in the body, its normal function becomes disrupted by age. This has consequences, not all of which are fully mapped or understood. Are those consequences plausibly large enough for greater attention to be given to mechanisms of pineal gland aging specifically? The authors of today's open access paper would argue that this is the case.
This highlights one of the challenges inherent in engaging with aging as a phenomenon. The body is complex, and contains many different complex systems, organs, and tissue types. If the approach taken to aging is to run down the list of body parts one by one, then making meaningful progress in the matter of treating aging as a medical condition is going to take a long time. The alternative of focusing on underlying pathological mechanisms rather than tissues has a similar issue. Even today there are many portions of the body for which little has been said in the context of slowing aging or producing rejuvenation. If one looks at the major avenues of development for rejuvenation therapies, such as senolytics and partial reprogramming, one finds that most of the development end of the field is focused on just a few age-related conditions and a few organs.
That said, at this still relatively early stage in the development of the longevity industry it is unclear as to whether anyone should be concerned about the above points, versus maintaining a laser focus on forging ahead as fast as possible to the first rejuvenation therapies. But it is something to think about.
Pineal gland senescence: an emerging ageing-related pathology?
The pineal gland is a photo-neuroendocrine gland located in the midline of the brain outside the blood-brain barrier. It is part of the epithalamus, is attached to the third ventricle by a short stalk, and can weigh up to 180 grams. Its primary role is to receive information about the light-dark cycle from the environment, which it responds to through the production and secretion of melatonin. When it is light, the suprachiasmatic nucleus (SCN) secretes gamma-amino butyric acid (GABA), which in turn inhibits neurons in the paraventricular nucleus (PVN) of the hypothalamus. In darkness, the SCN secretes glutamate, which activates pathways from parvocellular pre-autonomic neurons of the PVN via the superior cervical ganglion to stimulate melatonin production by the pineal gland in response to noradrenaline.
The pineal gland may undergo ageing-related structural and morphological changes, including calcification, gliosis, cyst formation, and reduced density of β-adrenergic receptors, which are hypothesised to reduce melatonin secretion.
We hypothesise that pineal gland senescence may represent an ageing-related pathology as it describes a decline in function. This causes a reduction in the secretion of melatonin that may contribute to ageing-related sleep disorders as well as other physiological, cognitive, and psychiatric dysfunctions related to disturbances in circadian rhythm and melatonin concentrations. The current paper will describe the pathophysiology of the pineal gland and will discuss whether pineal gland senescence should be considered as a diagnostic entity.
View the full article at FightAging
