When we have a bad day a simple text from our loved ones can easily make our day better. Similarly, all the cells of our body receive messages from certain chemical molecules to continue their function. These Chemical messengers which act as a mailman to deliver the messages to the exact cell are known as ‘HORMONES’. Hormones are way more interesting than one could imagine. They govern all physiological activity and behaviour throughout the day non-stop. These hormones which are classified into types for better understanding evokes a feeling of Contentment, Calmness, Sadness, Happiness and much more. These hormones give us a wake-up call in the morning and make us sleep in the night. A hormonal imbalance will wreak havoc on the physiological functions of our body. One such significant hormone that is known to regulate the circadian rhythm of the sleep cycle is Melatonin, an amine hormone. Melatonin plays other important roles in the body beyond sleep and this article would give brief insights on the use of melatonin in treating few clinical conditions
WHAT IS MELATONIN?
- Melatonin is an evolutionarily highly preserved chemical molecule that serves a crucial role in clock and calendar information to all living organisms from plants to humans.
- Melatonin is naturally occurring which primarily serves as a hormone found in the brain and body.
- Melatonin is majorly secreted by the parenchymal cells of the Pineal gland and to a lesser extent by extra pineal tissues which includes the retina, lens, GI tract, blood platelets and Harderian gland.
- Diurnal changes in human and their associated behaviour are governed by the Suprachiasmatic Nucleus of the Hypothalamus which is responsible for the circadian cycle of melatonin assembly.
- When our esoteric brain detects the darkness during the evening it releases a natural surge of melatonin which serves as an indicator for our body to sleep.
- Since it is secreted both in diurnal and nocturnal animal it is known as ‘Hormone of Darkness’
HISTORY AND BIOCHEMISTRY OF MELATONIN:
- It was Arone Lerner and his colleagues who discovered melatonin on 1958
- The term Melatonin was coined based on the molecule’s potential to reverse melanocyte-stimulating hormone (causes darkening of the skin) thereby lightening the skin in frogs
- Melatonin is chemically known as N-acetyl 5 Methyltryptamine with a half-life of 30 minutes.
- Melatonin exhibits high lipid content and water solubility which facilitates the molecule to diffuse through various cellular membranes.
- It is naturally synthesized from Tryptophan, a dietary amino acid that is taken by the pineal gland from the bloodstream by active transport and aids as a substrate for melatonin synthesis.
- The liver is the site of melatonin metabolism and clears about 90% of circulating melatonin in the bloodstream by excreting it in urine
ROLE OF MELATONIN IN HUMAN:
MELATONIN AND SLEEP DEPRIVATION:
- India is the 2nd most sleep-deprived country in the world with an average of 6.55 hours of sleeping time.
- Sleep is a global orchestrated neurochemical activity – rest state and deprivation of sleep will cause an epidemic in future.
- Chronic sleep deprivation and increased rate of other sleep disorders adversely affect adults and children thereby alarmingly increasing the incident rate of many serious illnesses including immunodeficiency, cancer, coronary heart disease, diabetes, obesity and various neuro disorders including dementia.
- A night of good sleep is a certification for a healthy lifestyle with good mental and physical health.
- In the era of modern technology where usage of mobiles, laptops have become unavoidable the blue rays emitted from the screen and increased screen time deteriorates health in a long run
- Many studies have pegged the alarming increase in the percentage of insomnia and other sleep disorder in adults and children which in turn leads to behavioural impairment.
CAUSES OF SLEEP DEPRIVATION:
There are several causes for lack of sleep including,
3. Sleep Apnea
5. Substance Misuse
6. Bipolar disorder
HOW MELATONIN CAN AID IN REGULATING THE SLEEP CYCLE?
- Melatonin has a plethora of effects and the most commonly known effect is inducing sleep.
- It is involved in circadian rhythms or diurnal variations (24-hour cyclic process) of the body.
- Melatonin produced naturally by the body is known as Endogenous Melatonin.
- When such endogenous melatonin falls shorts or decreases in level it would lead to wakefulness. Exogenous melatonin is also known as Synthetic melatonin is produced in pills, Liquids and chewable forms.
- Plasma Melatonin level is not alike throughout the day but it is found to be in higher level during the night. The sleep-wake cycle is only of many circadian rhythms which can be affected by both endogenous and exogenous factors like light, medication and behaviour.
- Since the hormone plays a significant role in sleep regulation during lack of sleep or jetlag when the melatonin level falls short one is prescribed melatonin supplements to suffice our body’s need. Insomnia a common psychiatric illness is due to decreased secretion of melatonin. Exogenous melatonin application in the treatment of depressive disorders has shown positive outcomes.
- Yoga and meditation have shown to induce melatonin secretion.
FOODS THAT CAN HELP IN SLEEP DEPRIVATION:
Various factors like controlled screen time, ambient environment to sleep, proper diet, decreased caffeine intake play an important role in rectifying the sleep cycle. Few natural sources of melatonin are as follows:
Herbal melatonin supplements are proved to induce sleep which includes
• Chamomile Tea
• Valerian root
• Lavender Tea
• Lemon balm
MELATONIN AND PANCREATITIS:
- Inflammation of the pancreas with associated injury to the exocrine parenchyma is known as Pancreatitis.
- The clinical manifestations range in severity from mild to severe.
- The pancreas is an organ which is located in the abdomen serving a crucial role in converting food into fuel for the cellular function
- The pancreas has two prime functions
- The exocrine function aids in digestion by employing several digestive enzymes.
- The endocrine function regulates blood glucose.
- Acute pancreatitis is a reversible pancreatic injury that is analogous to inflammation.
- When the cause of the disease is removing or treated, the gland can return to normal.
- Chronic pancreatitis is defined as inflammation of the pancreas with irreversible destruction of exocrine parenchyma, fibrosis, and, in the late stages, the destruction of endocrine parenchyma.
- Pancreatitis can cause serious conditions like kidney failure, diabetes, pancreatic cancer and malnutrition.
CAUSES OF PANCREATITIS:
- Abdominal surgery
- Cystic fibrosis
- Injury to the abdomen
- Pancreatic cancer
HOW MELATONIN CAN AID IN PANCREATIC PROTECTION
Several studies have pegged the kinship between severity of pancreatitis and melatonin blood level thereby proposing the possible role of melatonin as natural protection against the prognosis of the disease and in assessing the disease. Melatonin holds a crucial role as an immune response modulator and protects against tissue injury and oxidative damage by acting as direct scavengers of radial oxygen (ROS)and nitrogen species (RNS). They are reported to reduce morphological signs of inflammation, such as oedema, leukocyte infiltration and the vacuolization of the acinar cells by acting both directly and indirectly as antioxidant resulting in the reduction of lipid peroxidation in the pancreatic tissue. Increased nucleic acid content and DNA synthesis rate are induced by melatonin to rejuvenate the regeneration of tissue in acute pancreatitis. These studies provided an interlink between melatonin and its precursor L-Tryptophan which induces anti-inflammatory activity on conversion to melatonin.
MELATONIN AND PAROTID INFLAMMATION:
- Parotid glands are the largest of all salivary glands, located at the side of the face below and in front of the ear.
- Saliva holds significant importance in the digestion of food and also kills bacteria thereby protecting the oral cavity from infection.
- The parotid gland contributes about 25% of total saliva. Secretions from these glands are unloaded into the oral cavity by the Stensen duct
- the inflammation of one or both parotid glands are known as Parotitis. Viral parotitis is most common than bacterial parotitis. Staphylococcus aureus has been the most common pathogen interrelated with bacterial parotitis,
- the most common infection of parotid glands is Mumps which results in the puffiness of the cheeks due to the swelling of the gland and it infected by a paramyxovirus. The second most common parotitis in children is Juvenile Recurrent Parotitis (JRP)
- While acute parotitis occurs frequently in neonates, elderly people and postoperative patients, Chronic parotitis affect female often.
- Perinatally infected HIV children suffer from Chronic bilateral parotid enlargement
HOW MELATONIN IS INVOLVED WITH PAROTID INFLAMMATION:
Melatonin is known for its potential in managing various inflammatory diseases. They exert anti-inflammatory activity by regulating pro and anti-inflammatory cytokines which combat inflammation. Melatonin is also reported to limit the production of excessive mediators of the inflammatory process. Melatonin protects the oral cavity and gastrointestinal tract from several diseases by its characteristic anti-oxidant and anti-inflammatory property and exhibits paracrine effect on neighbour cells. They are also used as oral sedative, Hypnotic anxiolytic and acts as mediators in bone formation and resorption. Many pieces of evidence suggest that when salivary melatonin level is correlated with periodontal diseases thereby proving the role of melatonin in combating bacterial infections in salivary glands.
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