Dr. Govind Yadav (M.B.B.S) Karaganda State medical university Kazakhstan

1. KARAGANDA STATE MEDICAL
UNIVERSITY
TOPIC=AGE RELATED CHANGES OF
ENDOCRINE SYSTEM
NAME =GOVIND KUMAR
SUBMITTED TO= TIMUR SIR
GROUP NO= 3002
KARAGANDA 2017

2. The aging process can alter
neuroendocrine function at multiple levels
(i.e. through its effects on biogenic
aminergic and peptidergic neurons,
anterior pituitary cells and end organs)

3. THE HYPOTHALAMIC-PITUITARY
ADRENALAXIS
1. Corticotropin-releasing hormone (CRH or
CRF)
2. Corticotropin (ACTH, adrecorticotropic
hormone) secreted by anterior pituitary
corticotropes into the circulation
3. Adrenal hormone, primarily glucocorticoids,
from the adrenal cortex.

5. During Aging
 Menopause : E2 
 Andropause : T 
 Andrenopause : DHEA 
 Somatopause : GH/IGF-1 

6. EFFECT OF AGING ON THE HPA
 ACTH and glucocorticoid secretion
 Pituitary and adrenal involvement
 Stress activation and feedback inhibition
 CRH in Alzheimer’s disease

7. This bulk of evidence indicates that of the
alterations in the HPA that develop with aging, the
one most clearly demonstrable is a diminution in
feedback inhibition of ACTH and/or CRH systems
by glucocorticoids. Thus, there appears to be a
prolonged response to HPA activation by stressful
stimuli, suggesting an imbalance in the recovery
phase of HPA-mediated homeostasis. The
significance of decrease brain CRH levels in the
pathogenesis and treatment of Alzheimer’s disease
is currently under investigation.

8. EFFECT OF AGING ON THE
GROWTH HORMONE
 Physiologic secretion
 Sites of involvement
 Feedback inhibition and peripheral effect

9. Investigation of the age-related decline in episodec
GH secretion point to several sites in the
hypothalamic-pituitary axis where there may be
disruption of regulatory mechanism. At the
extrahypothalamic level, there is evidence for
diminished catecholamine neurotransmission that
could cause decreased stimulation of GHRH or
enhanced suppression of somatostatin release. At the
hypothalamic level, a large number of studies
provides convincing evidence that somatostatin
release is increased in aged animals, and the
proportion of the more potent and longer lasting
form, somatostatin-28 increase with age.

10. It is not clear if the synthesis and/or release of
GHRH decline with age. At the pituitary level, some
studies suggest that the pituitary responsiveness to
GHRH is decreased, possible due to a loss of
functional GHRH receptors. However, this may be
due to the age-associated decline in pituitary GH
content. Evidence from developmental studies
indicates that the inhibitory influence of
somatostatin on pituitary somatotropes is facilitated
during the aging process. Finally, there is no
evidence to indicate that feedback inhibition,
plasma clearance, or the peripheral actions of GH
are significantly altered in aged animal.

11. EFFECT OF AGING ON THE HYPOTHALAMIC-
PITUITARY-TESTICULAR AXIS (HPT)
 Testicular function
 Pituitary and feedback regulation
 Hypothalamic factors :
 GnRH
 Opioids
 Prolactin

12. There is considerable evidence that normal aging is
accompained by primary testicular failure that is modest
in degree in most individuals. This age-related testicular
failure result in diminished availability of testosterone
and inhibin as well as a decrease in sperm production.
While there is a gonadotropin response to this testicular
failure, there is growing evidence for subtle defects in
hypothalamic-pituitary regulation that may contribute to
the age-related decline in testicular function. Because of
the role that the central neurotransmitter norepinephrine
and opioids play in regulation of the hypothalamic
pituitary axis, alterations in these central neurotrnsmitters
with aging may contribute to the hypothalamic-pituitary
alterations observed

13. DISORDERS OF THE
NEUROENDOCRINE SYSTEM
Disorders of the neuroendocrine system have
clinical features related to hormone excess,
hormone deficiency, or local physical effect
from endocrine tumors. Particularly in the
area of hormone deficiency states. There
may be some challenge to clinical
recognition in an elderly patients population

14. Symptoms of adrenal, testicular or pituitary
insufficiency tend to be nonspecific and
include weight loss, fatigue, loss of appetite,
muscle wasting, and impaired sexual function.
As any of these findings may be
manifestations of chronic illness in an older
person, it is understandable that an endocrine
cause for such symptoms, which would be
relatively rare, can be overlooked.

15. The diagnostic challenge is further
compounded by age-related changes in
neuroendocrine function, as detailed
previously, since decreased growth hormone
and testosterone production occur with age
in the absence of neuroendocrine disease.

16.  Hypothalamic-Pituitary Disorders
a. Hypopituitarism
b. Acromegali
c. Gynecomastia
 Testicular disorders
 Disorder of the adrenal gland
a. Glucocorticoid excess
b. Mineralocorticoid excess
c. Adrenal insufficiency

17. GENERALAGE-RELATED
CHANGE
Structure Gland
Affected
Change
Most Gland
Target tissues of most
gland
Hypothalamus, pituitary
Some degree of glandular atrophy and fibrosis
Decreased rate of secretion
Decreased rate metabolic destruction of
hormone produced. Circulating hormone
levels remain fairly constant because of this
decrease, or decreased excretion through
the kidneys
Change in sensitivity
Progressive loss of sensitivity to feedback
control

18. Growth Hormone
 Decline about 50% of level early adulthood by
age 65
 Replacement – favorablr effects : increased
body mass, skin thickness, bone density
 GH decline could be a significant feature in
aging process.
 Consider as therapy : cancer, pancreas problem.

19. Thyroid
 Infiltration of lymphocytes and decrease in glandular cells.
 Associated in part with autoimmune destruction of the
gland
 Antithyroglobin antibodies
 Nodularity thyroid (postmortem : 27%)
 Hypothyroidism accurs in 3% to 4% elderly
 Hyperthyroidism 1%
 More common in woman
 Difficult to diagnosis (symptoms cause of other factors
 Iodine uptake little change
 Drug interaction  distort thyroid function tests

20. Adrenal Cortex
 Cortisol decline by 25% in elderly
 Plasma cortisol level are unchanged
 Renal clearance of cortisol are diminished
 Responsiveness to ACTH does not decline
 Pituitary to cortisol feedback : not does
 Progesterone – aldosterone : decrease with age
 Affect attitudes, behavior are related physical
factors
 Renin-aldosterone mechanism also decline with
age

21. Adrenal Medulla
The adrenal medulla may increase its
catecholamine and norepinephrine
production in elderly subjects, but the
cardiovascular response to norepinephrine
may decline. Nerve ending production of
norepinephrine may decline in some
patients, producing a delayed blood
pressure response to moving to an upright
posture (orthostatic hypotension).

22. Pancreas
 The islets Langerhans show little age-related
change
 Substantial decline in glucose tolerance
 Caused by decreased islets response to high blood
glucose
 In adequate insulin production
 Decreased cell membrane responsiveness to
insulin
 Increased insulin level in response to oral glucose
(in some affected elderly)

23. Change of Gastrin and Secretion
Diabetes mellitus and thyroid dysfunction are two
most important general categories of
endocrine/metabolic disorders in the elderly. They
are followed by the consequences of menopause in
women, hypocalcemia and hypercalcemia (either
dietary-absorptive or parathyroid in origin),
electrolyte problems related to adrenal or renal
changes, maglinancy-generated imbalances, and
drug-related endocrine problems. One reseacher has
observed that there is likely to be, on average, at
least one endocrine related problem in each new
elderly patient.

24. ANDROPAUSE :
 The aging of reproductive system
 Sexual activity among elderly people
 Disease and condition associated with advancing age :
 Impotence
 Gynecomastia
 Adenocarcinoma
 Hypertrophy prostate
 Testicular cancer