Melatonin is a hormone produced in the body that regulates sleep cycles. It is produced in the pineal gland and levels rise at night in response to darkness. As a supplement, melatonin is used to treat sleep disorders like jet lag or shift work disorder by helping to realign the body's circadian rhythm. It may also help with sleep quality, headaches, and depression. While generally safe at low doses, melatonin can cause side effects like drowsiness if taken too close to bedtime or in high amounts.
Melatonin is produced by the pineal gland from the essential amino acid L-tryptophan and declines significantly when a person reaches age 40. Melatonin also controls the circadian rhythm as well as deep stages of sleep. Learn more about this powerful sleep hormone and its benefits.
Melatonin is a hormone made in the body. It regulates night and day cycles or sleep-wake cycles. Melatonin in supplements is usually made in a lab.
Darkness triggers the body to make more melatonin, which signals the body to sleep. Light decreases melatonin production and signals the body to be awake. Some people who have trouble sleeping have low levels of melatonin. It's thought that adding melatonin from supplements might help them sleep.
Melatonin is produced by the pineal gland from the essential amino acid L-tryptophan and declines significantly when a person reaches age 40. Melatonin also controls the circadian rhythm as well as deep stages of sleep. Learn more about this powerful sleep hormone and its benefits.
Melatonin is a hormone made in the body. It regulates night and day cycles or sleep-wake cycles. Melatonin in supplements is usually made in a lab.
Darkness triggers the body to make more melatonin, which signals the body to sleep. Light decreases melatonin production and signals the body to be awake. Some people who have trouble sleeping have low levels of melatonin. It's thought that adding melatonin from supplements might help them sleep.
Melatonin Transcription:
Melatonin controls the circadian rhythm as well as the deep stages of sleep.
Melatonin is produced by the pineal gland and declines significantly when a person reaches age 40.
Melatonin levels peak at night and decrease throughout the day with the help of natural sunlight.
The essential amino acid (tryptophan) from which melatonin is derived helps to regulate your circadian sleep rhythm.
Melatonin is considered a super antioxidant due to its ability to cross the blood-brain barrier.
Melatonin also works with cholecystokinin in the digestive tract to decrease the likelihood and severity of many symptoms associated with gastric ulcers and colitis.
Your melatonin levels will naturally decrease with age. This is why some older people will sleep less even though they still need the same amount of sleep.
Cortisol (the stress hormone) is partially regulated by melatonin.
Culprits of Low Melatonin Levels:
Alcohol
Vitamin B12
Caffeine
NSAID anti-inflammatory medication
Beta-blocker medication
Glucocorticoid medication
Cigarettes
Antidepressants
Frequent stress
Melatonin is a natural substance that should be taken at night. It is not addictive or habit forming.
Sleep Facts:
New parents lose 400-750 hours of sleep during their newborn’s first year.
The number of car accidents decreases in Canada during daylight savings.
Constant access to the internet is one of the biggest contributors to lack of sleep.
Ducks are able to keep one half of their brain awake, while the other half is asleep, in order to survive predator attacks.
http://vitalitmed.com/hormones/melatonin/
Globally 14.2 million people - 30-69 years old die / year from the modern Lifestyle Diseases.These diseases emerged as bigger killers than infectious or hereditary ones. Orthopaedic complaints accounts for the epidemic proportions (cases of low back ache, joint disorders, degenerative diseases that we find in our clinics and also around us). Lack of proper sleep and the continuous exposure to Blue light from television, PC and laptop screens are of the sources of the worst blue lights one can be exposed to and by leaving a television set or laptop screen on during the night will suppress melatonin production significantly. Melatonin is distributed widely in nature; it acts as a photoperiod messenger molecule, transducing photoperiod changes to various cyclic function (reproduction, sleep-wake rhythms). Melatonin is very important antioxidant . Melatonin influences various cell mechanisms . We have to know how to Improve and Protect our Melatonin Production by Improving our sleep hygiene.
Introduction to Physiological and pathological role of serotonin
Autocoids, Classification, synthesis ,Serotonergic receptors, Physiological actions, Pathophysiological role
Presented by
K.Firdous banu
Department of Pharmacology
Neurotransmission (Latin: transmission "passage, crossing" from transmitter "send, let through"), is the process by which signalling molecules called neurotransmitters are released by the axon terminal of a neuron and bind to and react with the receptors on the dendrites of another neuron
introduction
pituitary gland hormone
factor affecting secretion
function
regulation of secretion of prolactin
causes and symptoms of hypoprolactinaemia
causes and symptoms of hyperprolactinaemia
diagnosis
treatment
mechanism of prolactin
role of prolactin
uses
Melatonin Transcription:
Melatonin controls the circadian rhythm as well as the deep stages of sleep.
Melatonin is produced by the pineal gland and declines significantly when a person reaches age 40.
Melatonin levels peak at night and decrease throughout the day with the help of natural sunlight.
The essential amino acid (tryptophan) from which melatonin is derived helps to regulate your circadian sleep rhythm.
Melatonin is considered a super antioxidant due to its ability to cross the blood-brain barrier.
Melatonin also works with cholecystokinin in the digestive tract to decrease the likelihood and severity of many symptoms associated with gastric ulcers and colitis.
Your melatonin levels will naturally decrease with age. This is why some older people will sleep less even though they still need the same amount of sleep.
Cortisol (the stress hormone) is partially regulated by melatonin.
Culprits of Low Melatonin Levels:
Alcohol
Vitamin B12
Caffeine
NSAID anti-inflammatory medication
Beta-blocker medication
Glucocorticoid medication
Cigarettes
Antidepressants
Frequent stress
Melatonin is a natural substance that should be taken at night. It is not addictive or habit forming.
Sleep Facts:
New parents lose 400-750 hours of sleep during their newborn’s first year.
The number of car accidents decreases in Canada during daylight savings.
Constant access to the internet is one of the biggest contributors to lack of sleep.
Ducks are able to keep one half of their brain awake, while the other half is asleep, in order to survive predator attacks.
http://vitalitmed.com/hormones/melatonin/
Globally 14.2 million people - 30-69 years old die / year from the modern Lifestyle Diseases.These diseases emerged as bigger killers than infectious or hereditary ones. Orthopaedic complaints accounts for the epidemic proportions (cases of low back ache, joint disorders, degenerative diseases that we find in our clinics and also around us). Lack of proper sleep and the continuous exposure to Blue light from television, PC and laptop screens are of the sources of the worst blue lights one can be exposed to and by leaving a television set or laptop screen on during the night will suppress melatonin production significantly. Melatonin is distributed widely in nature; it acts as a photoperiod messenger molecule, transducing photoperiod changes to various cyclic function (reproduction, sleep-wake rhythms). Melatonin is very important antioxidant . Melatonin influences various cell mechanisms . We have to know how to Improve and Protect our Melatonin Production by Improving our sleep hygiene.
Introduction to Physiological and pathological role of serotonin
Autocoids, Classification, synthesis ,Serotonergic receptors, Physiological actions, Pathophysiological role
Presented by
K.Firdous banu
Department of Pharmacology
Neurotransmission (Latin: transmission "passage, crossing" from transmitter "send, let through"), is the process by which signalling molecules called neurotransmitters are released by the axon terminal of a neuron and bind to and react with the receptors on the dendrites of another neuron
introduction
pituitary gland hormone
factor affecting secretion
function
regulation of secretion of prolactin
causes and symptoms of hypoprolactinaemia
causes and symptoms of hyperprolactinaemia
diagnosis
treatment
mechanism of prolactin
role of prolactin
uses
Neurohumoral transmission in central nervous systemRishabhchalotra
Neurohumoral Transmission in Central Nervous System (Detailed study about Neurotransmitters- Histamine, Serotonin, Dopamine, GABA, Glutamate, and Glycine).
1-ENDOCRINOLOGY-Part-I.PPT PART OF THE HUMAN BODYbarilloanfhal
What Is Endocrinology?
The Basics
Endocrinology is a branch of medicine that deals with the endocrine system, which controls the hormones in your body. An endocrinologist is a physician who specializes in the field of endocrinology. Endocrinologists diagnose and treat a wide range of conditions affecting the endocrine system, including diabetes mellitus, thyroid disorders, osteoporosis, growth hormone deficiency, infertility, cholesterol problems, hypertension (high blood pressure), obesity and more.
How the Endocrine System Works
The endocrine system’s glands and organs release hormones that regulate a number of vital functions of our body. These glands include the hypothalamus, pineal body, pituitary, thyroid, parathyroids, adrenals, pancreas, testes and ovaries.
The hormones in your body all have specific jobs to complete. There are up to 40 different hormones circulating in your blood at any time. Once released into the bloodstream, a hormone travels throughout the body until it reaches its specific destination(s) to perform its function. These destinations, called targets, can be located either on other endocrine glands or on other organs and tissues in the body.
When a hormone reaches its target, it tells that part of your body what work to do, when to do it and for how long. Hormones are often referred to as the “messengers” because they help different parts of the body communicate. Overall, they are involved in many different processes in the body, including:
Blood sugar control
Growth and development
Metabolism (the process of getting and maintaining energy in the body)
Regulation of heart rate and blood pressure
Sexual development and function
Reproduction
Mood
What Happens When the Endocrine System Does Not Work?
Hormonal function is a balancing act. Too much or too little of one hormone can have an impact on the release of other hormones. If this hormonal imbalance occurs, some of your body’s systems will not work properly.
These imbalances can often be corrected by the body itself. Your body has built-in mechanisms to keep track of and respond to any changes in hormone levels to bring them back to normal and restore the balance.
Sometimes, however, this system goes wrong and there can be a problem that the body can’t fix itself. In this case, a primary care physician will refer you to an endocrinologist, who is an expert in treating frequently complex (and often chronic) conditions which can involve several different systems within the body.
The Anatomy of the Endocrine System
The endocrine system is made up of a collection of glands. Each gland has a specific function in the body, and all these glands work together to regulate vital functions of our body.
Adrenal glands
Located just above the kidneys, adrenal glands are responsible for the secretion of several hormones which maintain the body’s salt and water balance that in turn regulate blood pressure, help the body cope with and respond to stress, regulate body meta
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
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1. Melatonin (5-methoxy-N- Melatonin
acetyltryptamine,) Systematic (IUPAC) name
N-[2-(5-methoxy-1H-indol-3-yl)ethyl]
is a hormone found in all living ethanamide
creatures from algae to humans, at Identifiers
levels that vary in a daily cycle. CAS number 73-31-4
ATC code N05CM17
Many biological effects of melatonin
are produced through activation of PubChem 896
melatonin receptors, while others DrugBank APRD00742
are due to its role as a pervasive and Chemical data
extremely powerful antioxidant with Formula C13H16N2O2
a particular role in the protection of Mol. mass 232.278 g/mol
nuclear and mitochondrial DNA. Pharmacokinetic data
Bioavailability 30 – 50%
Metabolism Hepatic via CYP1A2
mediated 6-
hydroxylation
Half life 35 to 50 minutes
Production Excretion Urine
In higher animals, melatonin is
produced by pinealocytes in the pineal gland (located in the brain)
and also by the retina, lens and GI tract. It is naturally
synthesized from the amino acid tryptophan (via synthesis of
serotonin) by the enzyme 5-hydroxyindole-O-methyltransferase.
Production of melatonin by the pineal gland is under the influence
of the suprachiasmatic nucleus (SCN) of the hypothalamus which
receives information from the retina about the daily pattern of
light and darkness. Both SCN rhythmicity and melatonin production
are affected by non-visual light information traveling not through
1
2. the optic nerve, but through the recently-identified hypothalamic
tract.
The light/dark information reaches the SCN via a subpopulation of
inner retinal ganglion cells, which are intrinsically-photosensitive
photoreceptor cells, distinct from those involved in the visual
system. These cells represent approximately 2% of retinal ganglion
cells in humans and express the non-visual photopigment melanopsin
(1). The sensitivity of melanopsin fits with that of a vitamin A-
based photopigment with a peak sensitivity at 484 nm (blue light)
(2). This photoperiod cue entrains the circadian rhythm, and the
resultant production of specific “dark” and “ light” induced neural
and endocrine signals regulates behavioral and physiological
circadian rhythms.
Melatonin may also be produced by a variety of peripheral cells
such as bone marrow cells (3,4), lymphocytes and epithelial cells.
Usually, the melatonin concentration in these cells is much higher
than that found in the blood but it does not seem to be regulated
by the photoperiod.
Melatonin is also synthesized by various plants, such as rice, and
ingested melatonin has been shown to be capable of reaching and
binding to melatonin binding sites in the brains of mammals.
Distribution
2
3. Melatonin produced in the pineal gland acts as an endocrine
hormone since it is released into the blood. By contrast, melatonin
produced by the retina and the gastrointestinal (GI) tract acts as
a paracrine hormone.
Roles in the animal kingdom
Many animals use the variation in duration and quantity of
melatonin production in each day as a seasonal clock In seasonal
breeders which do not have long gestation periods, and which mate
during longer daylight hours, the melatonin signal controls the
seasonal variation in their sexual physiology, and similar
physiological effects can be induced by exogenous melatonin in
animals including mynah birds and hamsters Melatonin can suppress
libido by inhibiting secretion of luteinizing hormone (LH) and
follicle stimulating hormone (FSH) from the anterior pituitary
gland, especially in mammals that have a breeding season when
daylight hours are long. The reproduction of long-day breeders is
repressed by melatonin and the reproduction of short-day
breeders is stimulated by melatonin.
During the night, melatonin regulates leptin, lowering the levels;
.
Melatonin is also related to the mechanism by which some
amphibians and reptiles change the color of their skin.
3
4. Roles in humans
Biological clock
In humans, melatonin is produced by the pineal gland, a gland about
the size of a pea, located in the center of the brain on the dorsal
surface of diencephalon. The melatonin signal forms part of the
system that regulates the circadian cycle by chemically causing
drowsiness, but it is the central nervous system that controls the
daily cycle in most components of the paracrine and endocrine
systems rather than the melatonin signal (as was once postulated).
Light dependence
Production of melatonin by the pineal gland is inhibited by light and
permitted by darkness. For this reason melatonin has been called
"the hormone of darkness" and its onset each evening is called the
Dim-Light Melatonin Onset (DLMO). Secretion of melatonin, and its
level in the blood, peaks in the middle of the night, and gradually
falls during the second half of the night, with normal variations in
timing according to an individual's chronotype.
Until recent history, humans in temperate climates were exposed
to up to 18 hours of darkness in the winter. In the modern world,
artificial lighting reduces this to typically eight hours or less per
day all year round. Even low light levels inhibit melatonin production
to some extent, but over-illumination can create significant
reduction in melatonin production. Since it is principally blue light
that suppresses melatonin wearing glasses that block blue light in
the hours before bedtime may avoid melatonin loss. Use of blue-
4
5. blocking goggles the last hours before bedtime has also been
advised for people who need to adjust to an earlier bedtime, as
melatonin promotes sleepiness.
Reduced melatonin production has been proposed as a likely factor
in the significantly higher cancer rates in night workers, and the
effect of modern lighting practice on endogenous melatonin has
been proposed as a contributory factor to the larger overall
incidence of some cancers in the developed world. As inadequate as
blood concentrations may be in brightly lit environments, some
scientists now believe that a person's overnight output of
melatonin can be further jeopardized each time he or she
interrupts his or her sleep and turns on a bright light (suggesting
that using a less-bright nightlight would be safer). Others suggest
that such short exposures do no harm.
Antioxidant
Besides its primary function as synchronizer of the biological
clock, melatonin may exert a powerful anti-oxidant activity. In
many lower life forms, it serves only this purpose
Melatonin is a powerful antioxidant that can easily cross cell
membranes and the blood-brain barrier. Unlike other antioxidants,
melatonin does not undergo redox cycling, the ability of a molecule
to undergo reduction and oxidation repeatedly. Redox cycling may
allow other antioxidants (such as vitamin C) to regain their
antioxidant properties. Melatonin, on the other hand, once
oxidized, cannot be reduced to its former state because it forms
several stable end-products upon reacting with free radicals.
5
6. Therefore, it has been referred to as a terminal (or suicidal)
antioxidant.
Recent research indicates that the first metabolite of melatonin in
the melatonin antioxidant pathway may be N(1)-acetyl-N(2)-
formyl-5-methoxykynuramine or AFMK rather than the common,
excreted 6-hydroxymelatonin sulfate. AFMK alone is detectable in
unicellular organisms and metazoans. A single AFMK molecule can
neutralize up to 10 ROS/RNS since many of the products of the
reaction/derivatives (including melatonin) are themselves
antioxidants, and so on. This capacity to absorb free radicals
extends at least to the quaternary metabolites of melatonin, a
process referred to as "the free radical scavenging cascade". This
is not true of other, conventional antioxidants. In animal models,
melatonin has been demonstrated to prevent the damage to DNA
by some carcinogens, stopping the mechanism by which they cause
cancer.
The antioxidant activity of melatonin may reduce damage caused
by some types of Parkinson's disease, may play a role in preventing
cardiac arrhythmia and may increase longevity; it has been shown
to increase the average life span of mice by 20% in some studies.
Immune system
While it is clear that melatonin interacts with the immune system,
the details of those interactions are unclear. There have been few
trials designed to judge the effectiveness of melatonin in disease
treatment. Most existing data are based on small, incomplete,
clinical trials. Any positive immunological effect is thought to
result from melatonin acting on high affinity receptors (MT1 and
6
7. MT2) expressed in immunocompetent cells. In preclinical studies,
melatonin may enhance cytokine production. and by doing this
counteract acquired immunodeficiences. Some studies also suggest
that melatonin might be useful fighting infectious disease including
viral and bacterial infections. Endogenous melatonin in human
lymphocytes has been related to interleukin-2 (IL-2) production
and to the expression of IL-2 receptor This suggests that
melatonin is involved in the clonal expansion of antigen-stimulated
human T lymphocytes. When taken in conjunction with calcium, it is
an immunostimulator and is used as an adjuvant in some clinical
protocols conversely, the increased immune system activity may
aggravate autoimmune disorders. In rheumatoid arthritis patients,
melatonin production has been found increased when compared to
age-matched healthy controls.
Dreaming
Many supplemental melatonin users have reported an increase in
the vividness or frequency of dreams. Extremely high doses of
melatonin (50mg) dramatically increased REM sleep time and dream
activity in both narcoleptics and those without narcolepsy
Many psychoactive drugs, such as LSD and cocaine, increase
melatonin synthesis It has been suggested that nonpolar (lipid-
soluble) indolic hallucinogenic drugs emulate melatonin activity in
the awakened state and that both act on the same areas of the
brain.
It has been suggested that psychotropic drugs be readmitted in
the field of scientific inquiry and therapy. If so, melatonin may be
prioritized for research in this reemerging field of psychiatry.
7
8. Use as medicinal supplement
Exogenous melatonin, usually taken orally, is, together with light
therapy, the standard treatment for delayed sleep phase
syndrome. It appears to have some use against other circadian
rhythm sleep disorders, such as jet lag. It has been studied for
the treatment of cancer, immune disorders, cardiovascular
diseases, depression, seasonal affective disorder (SAD), and
sexual dysfunction. A study by Alfred J. Lewy and other
researchers at Oregon Health & Science University found that it
may ameliorate SAD and circadian misalignment, but as of 2006 it
is known to affect the timing of endogenous melatonin production
during long-term melatonin treatment in rats, raising the risk that
it can exacerbate both clinical depression and SAD. Basic research
indicates that melatonin may play a significant role in modulating
the effects of drugs of abuse such as cocaine.
Proposed medical indications
Treatment of circadian rhythm disorders
Exogenous melatonin, usually taken orally in the afternoon or
evening, is, together with light therapy upon awakening, the
standard treatment for delayed sleep phase syndrome and non-24-
hour sleep-wake syndrome. See Phase response curve, PRC. It
appears to have some use against other circadian rhythm sleep
disorders, such as jet lag and the problems of people who work
rotating or night shifts.
8
9. Preventing ischemic damage
Melatonin has been shown to reduce tissue damage in rats due to
ischemia in both the brain and the heart; however, this has not
been tested in humans.
Sleep aid
Melatonin may be used as an adjunct to sleep in children, for
certain diagnostic tests.
Learning, memory and Alzheimer's
Melatonin receptors appear to be important in mechanisms of
learning and memory in mice, and melatonin can alter
electrophysiological processes associated with memory, such as
long-term potentiation (LTP). Melatonin has been shown to prevent
the hyperphosphorylation of the tau protein in rats.
Hyperphosphorylation of tau protein can result in the formation of
neurofibrillary tangles, a pathological feature seen in Alzheimer's
disease. Thus, melatonin may be effective for treating Alzheimer's
Disease. These same neurofibrillary tangles can be found in the
hypothalamus in patients with Alzheimer's, adversely affecting
their bodies' production of melatonin. Those Alzheimer's patients
with this specific affliction often show heightened afternoon
agitation, called sundowning, which has been shown in many studies
to be effectively treated with melatonin supplements in the
evening.
9
10. ADHD
ADHD is most commonly treated with methylphenidate which may
cause insomnia in approximately 94% of its users.[citation needed]
Research shows that after melatonin is administered to the
patients, the time needed to fall asleep is significantly reduced.
Before the melatonin was administered, the time needed to fall
asleep ranged from 15 minutes to 240 minutes. After the melatonin
was administered, the time needed to fall asleep ranged from 15
minutes to 64 minutes. Furthermore, the effects of the melatonin
after three months showed no change from its effects after one
week of use.
Fertility
Recent research has concluded that melatonin supplementation in
perimenopausal women produces a highly significant improvement in
thyroid function and gonadotropin levels, as well as restoring
fertility and menstruation and preventing the depression
associated with the menopause.
However, at the same time, some resources warn women trying to
conceive not to take a melatonin supplement.
Headaches
Several clinical studies indicate that supplementation with
melatonin is an effective preventative treatment for migraines and
cluster headaches.
10
11. Depression
Melatonin has been shown to be effective in treating one form of
depression, seasonal affective disorder.
Other
Some studies have shown that melatonin has potential for use in
the treatment of various forms of cancer, HIV, and other viral
diseases; however, further testing is necessary to confirm this.
Histologically speaking, it is also believed that melatonin has some
effects for sexual growth in higher organisms.
Use as a dietary supplement
The primary motivation for the use of melatonin as a supplement is
as a natural aid to better sleep, with other incidental benefits to
health and well-being due to its role as an antioxidant and its
stimulation of the immune system and several components of the
endocrine system.
Studies from Massachusetts Institute of Technology say that
melatonin pills sold as supplements contain three to ten times the
amount needed to produce the desirable physiologic nocturnal
blood melatonin level for enhancement of nighttime rest. Dosages
are designed to raise melatonin levels for several hours to enhance
quality of sleep, but some studies suggest that smaller doses are
just as effective at improving sleep quality. High dose melatonin
can even be counterproductive: Lewy & al provide support to the
"idea that too much melatonin may spill over onto the wrong zone
of the melatonin phase-response curve." In their study, 0.5 mg of
11
12. melatonin was effective while 20 mg wasn't. Melatonin
supplementation for sleep problems is available without
prescription in most cases in the United States and Canada, while
it is available only by prescription or not at all in some other
countries. Melatonin supplements are available as oral supplements
and transdermal melatonin or "melatonin sleep patch".
Melatonin is involved in the regulation of body weight, and may be
helpful in treating obesity (especially when combined with calcium).
Safety of supplementation
Melatonin derived from animal sources may be contaminated with
viral material, so synthetic melatonin is generally used to avoid this
risk. Melatonin is practically nontoxic and exhibits almost no short-
term side effects. No studies have as yet been conducted to
determine whether there are any long-term side effects. There
are, however, case reports about patients who have taken the
supplement for years.
Ingesting melatonin supplements may cause some unwanted side
effects, especially at high doses (~more than 3 mg/day): hormone
fluctuations, irritability, reduced blood flow, and increased sleep
disturbances, including vivid nightmares.
Melatonin taken in combination with monoamine oxidase inhibitors
(MAOIs) can lead to overdose because MAOIs inhibit the
breakdown of melatonin by the body.
12
13. Exogenous melatonin normally does not affect the endogenous
melatonin profile, merely advancing the phase of endogenous
melatonin production in time if taken at an appropriate time of day.
In individuals with auto-immune disorders, there is concern that
melatonin supplementation may exacerbate symptoms due to
stimulation of the immune system.
Melatonin causes somnolence, and therefore caution should be
shown when driving, operating machinery, etc. When taken several
hours before bedtime in accordance with the Phase Response
Curve for melatonin in humans, the dosage should be so tiny as to
not cause tiredness/sleepiness.
Individuals who experience orthostatic intolerance, a
cardiovascular condition that results in reduced blood pressure and
blood flow to the brain when a person stands, may experience a
worsening of symptoms when taking melatonin supplements, a study
at Penn State College of Medicine's Milton S. Hershey Medical
Center suggests. Melatonin can exacerbate the symptoms by
reducing nerve activity in those who experience the condition, the
study found.
13
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