Ageing pineal gland

Haidar, C. Gupta, D. (1990). Sex- and age-dependent nature of the cytoplasmic 5 alpha-dihydrotestosterone (DHT) binding site/receptor in bovine pineal gland. J. Pineal Res. 8, 289-95. 

Melatonin (lV-acetyl-5-methoxytryptamine) is a neuro-hormone secreted by the pineal gland from the amino acid precursor [,-tryptophan. Its endogenous secretion is photosensitive and has a circadian rhythm—plasma melatonin concentrations are highest at night in both diurnal and nocturnal animals, and fall with age (1). The nocturnal melatonin peak coincides with a drop in body temperature and increased sleepiness in healthy humans. Oral melatonin has a short half-life (30-50 minutes) and extensive first-pass metabolism. Its clearance is reduced in severe liver disease (2). 

The natural production of melatonin by the pineal gland peaks at the age of only four or five years of age. Since a decrease in its production occurs during sexual maturation, researchers warn that taking it during adolescence may have a detrimental effect on puberty. 

Melatonin is not an herb but rather is a naturally occurring hormone produced in the pineal gland from tryptophan. It is also commercially synthesized. Endogenously, melatonin is released during sleep periods, and levels are low during the day. " As a supplement, melatonin has been most studied as a preventative/treatment for jet lag and as a sedative-hypnotic. For jet lag, patients are advised to take 5 mg daily at bedtime beginning three days prior to travel and continuing for three days after travel is complete. " Levels of melatonin decrease with age, so it has been studied in elderly patients with sleep... 

Various other concretionary or nodular bodies occur in various tissues and organs of humans. Dahllite seems to be the principal mineral involved in calcification products occurring in the spleen, prostate gleind, appendix, testes, the walls of the bronchi and in the lungs — the last in connection with histoplasmosis. However, chronic renal failure produces calcified visceral tissues which are either whitlockite or its immediate precursor (LeGeros et al., 1973). The sand of the pineal gland is dahllite, but may be normal rather than pathologic it seems to increase in quantity with age, and its function is unknown. 

Pierpaoli W. Neuroimmunomodulation of aging. A program in the pineal gland. Ann NY Acad Sci 1998 840 491-497. 

Melatonin is a hormone secreted mainly by the pineal gland. It is synthesized from tryptophan, and its characteristic circadian rhythm is ruled by light. Touitou et al.86 have reviewed the relationship of melatonin and aging. Since the circulating levels of melatonin decrease with aging, questions arise regarding its origin and/or the consequences of this condition, which may be related to the availability of tryptophan. 

The pineal glands of rats 12-28 months old exhibited regressive changes of different intensity with age (Boya and Calvo 1984). In type I pinealocytes there was a marked increase in dense bodies as well as the occasional appearance of wide cell profiles full of vesicles. Type II pinealocytes showed nuclear infoldings and cytoplasmic deposits of lipofuscin. 

Human pineal glands of adult or older age sometimes have iron-rich interlobular pigmented cells. 

Light microscopy of the thyroid gland of pineal-grafted and control ageing mice showed a very remarkable maintenance of a youthful thyroid morphology, as compared to control (Pierpaoli and Regelson 1994). 

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