The pineal aging and death program: life prolongation in pre-aging pinealectomized mice.

Area of Science:

• Neuroendocrinology
• Chronobiology
• Gerontology

Background:

• The pineal complex in the brain is hypothesized to regulate life stages including growth, fertility, aging, and death.
• Transplantation studies suggest the pineal gland's role in aging, with old glands accelerating aging in young recipients.

Purpose of the Study:

• To investigate the existence of an internal biological clock within the pineal gland that actively signals aging and death.
• To determine the effect of pinealectomy (PX) at various ages on mouse lifespan and aging parameters.

Main Methods:

• Surgical pinealectomy (PX) was performed on BALB/c mice at 3, 5, 7, 9, 14, and 18 months of age.
• Lifespan was evaluated, and periodic measurements of blood, hormonal, and metabolic parameters were recorded.

Main Results:

• Pinealectomy at 3 and 5 months accelerated aging, while PX at 7 and 9 months had no significant effect.
• Remarkable life prolongation was observed in mice pinealectomized at 14 months; no effect was seen at 18 months.
• Hematological and hormonal-metabolic values corroborated the aging-promoting or -delaying effects.

Conclusions:

• The pineal complex plays a significant evolutionary-developmental role in regulating growth, fertility, and aging.
• The pineal gland appears to have a dominant role in initiating and progressing aging, acting as a death signal, though its mechanism remains unknown.
• Grafting a young pineal gland into a young mouse accelerated aging, further supporting the pineal's influence on the aging process.