ICT role in 21st century education and it's challenges.
Melatonin presented by noor zahra
1.
2. Contents
Introduction
Properties of Melatonin
Melatonin Structure
Synthesis of Melatonin
How does it release
Metabolism of Melatonin
Physiological Role of Melatonin
Therapeutic Use
Cause of low Melatonin level
Adverse Effects
Demand for Melatonin in developed countries
3. Introduction
Melatonin is a Hormone.
Arone Lerner in 1958 discovered this hormone
Chemically it is known as N-acetyl-5-methoxytryptamine.
It is a known as “Hormone of darkness”
4. Properties of Melatonin
This hormone is naturally produced by the pineal gland.
It’s a serotonin derived hormone
It modulates sleep patterns.It’s synthesis & secretion is
directly controlled by light.
The secretion decrease with light and increase in the dark.
Except Penial gland it also produced in GIT, Bone
Marrow, Leucocyte etc.
6. Synthesis of Melatonin
It is naturally synthesized from the amino acid tryptophan.Melatonin produced in the
pineal gland acts as an endocrine hormone since it is released into the blood.
OH
N
H
CH3
N-acetylserotonin
H
N
O
HIOMT
Melatonin
H
N
CH3O
N
H
CH3
O
7. How does Melatonin release
Light Pupil Rod
Cone
Photosensitive
Cell
Circadian
Clock
Sleep/Wake
cycle
IPRGc
9. Secretion
Melatonin secretion starts at 3-4 months of age.
Peak levels at 1-3 years of age.
Slightly lower levels through early adulthood.
Peak levels for 70 year old is ¼ of young adult.
Metabolism
Liver is the 1st site for metabolism & clears >90% of circulation
melatonin.
Melatonin is 1st hydroxylated then excreted in urine as sulphate &
glucuronide conjugates.
About 1 % of melatonin remains unchanged in urine.
10. Melatonin's functions as an antioxidant include:
a) Direct free radical scavenger.
b) Stimulation of antioxidative enzymes.Increasing the efficiency of
mitochondrial oxidative phosphorylation and reducing electron leakage
and Increase the efficiency of other antioxidants.
2:Menstral Benefits
a) When estradiol is administered to postmenopausal women, their
melatonin levels increase.This occurs naturally throughout a woman’s
life before she reaches menopause, having a positive effect on women’s
menstrual cycles.
Physiological role of melatonin
1:Melatonin as Antioxidant
11. 2:Melatonin in Immune System
Immunological effect is thought to result from melatonin acting on
high affinity receptors (MT1 and MT2).
Melatonin may enhance cytokine production.
Melatonin might be useful fighting infectious disease including viral,
such as HIV and bacterial infections , and cancer.
Endogenous melatonin in human lymphocytes has been related to
interleukin-2 (IL-2) production.
12. 3:Melatonin in Cancer
Melatonin has also been thought to fight against cancer
(especially prostate, breast and colon cancers).
Melatonin is inhibitory action of tumor growth.
The apparent melatonin induced suppression of prolactin ,
when prolactin is a hormone that can promote mammary
cancer .
Several studies reported that , during the initial state of tumor
development , melatonin is increased an early stage of cancer
with malignant cells that do not growth.
13. How does Melatonin work in Cancer:
Apoptosis is the primary mechanism by which melatonin converts
tumor cell to healthy cell.
High level of Melatonin suppress P53(tumor promoting gene), COX-2,
P300, NF-kB signaling, and inhibit the uptake of Linoleic Acid(LA).
LA is responsible for fatty acid growth and tumor cell proliferation.
It shows anti-estrogenic action by interfering at different level with the
estrogen signaling pathways.
And behaves as selective estrogen enzyme modulator. Thus it reduce
breast cancer.
14. 4:Melatonin works in Sleep and digestive tract
Melatonin is “opening gate of sleep”
SCN is the site of internal biological clock.
Elevated melatonin level occur at night & it’s a coincident with
sleep and Increase in vivid dreaming or frequency of dreams.
Extremely high doses of melatonin (50 mg) increased REM
sleep time .Many drugs such as “Cannabis”and
“Cocaine”increase the melatonin synthesis.
Melatonin works with cholecystokinin in the digestive tract to
decrease the likelihood and severity of many symptoms
associated with gastric ulcers and colitis.
15. Other Functions:
Exogenous melatonin decreases leptin production.
Reported that melatonin intake reduced BP during sleep, without
effect of the heart rate.
One of the claimed action of melatonin that anti aging effect.
Melatonin controls the circadian rhythm as well as deep stages of
sleep.
It increasing secretion of GnRH and sex hormones.
Inhibits growth and development of sex organs beforepuberty.
Many biological effects of melatonin are produced through activation of
melatonin receptors.
16. Therapeutic uses:
Melatonin is used in the treatment of
Cancer
Immune disorders
Cardiovascular diseases
Depression
Seasonal effective sleep disorders
Sexual disfunction
Fertility
Headache
Used as dietary supplement
Used to Prevent ischemic damage
18. Adverse Effects:
Some unwanted effects in some people especially at high doses(3mg/day
or more).
Nausea
Vivid dreams or nightmares
Reduced blood flow
Hypothermia
Hormone fluctuations
Drowsiness , Dizziness
Confusion
Hallucinations
Fatigue
Menstrual irregularities
19. Demand of Melatonin in developed countries
Serum melatonin level have been shown to increase after taking
fluvoxamine.It is interacts with nifedipine increasing the blood
pressure and heart rate.
Global melatonin supplements market to grow at a compound annual
growth rate (CAGR) of over 12% from 2017 to 2021, according to their
latest report.
The demand for melatonin supplements is more in developed countries
such as the Pakistan United States, Canada, the United Kingdom, and
Germany. This is due to increased awareness about melatonin supplements
and the growing prevalence of circadian rhythm disorders in these
countries.
