Hormones and Neurotransmitters: The Differences and Curious Similarities

Alpana and Murari Chaudhuri wrote . . . . . . . . .

Overview

Neurotransmitters and hormones are two different types of chemicals that carry signals from one part of the body to another. Both chemicals play an important part in the body’s physiology. They control a variety of physical and psychological functions, including our mood, our eating patterns, our ability to learn, and our sleep cycles.

The Differences

Hormones and neurotransmitters are different chemical messengers, the former produced by the endocrine glands and the latter by the nervous system.

Hormones are usually secreted from the endocrine system and released into the bloodstream, but they act on distant target cells. Some hormones, like melatonin and cortisol, are actually produced in the brain, released in the blood, and affect other parts of the body.

On the other hand, neurotransmitters are released from the presynaptic nerve terminal in the brain. They move across the synaptic cleft, a small space between two adjacent neurons, and move to the next neuron (known as a postsynaptic neuron). There they bind to specific receptors, causing changes in the electrical properties of target cells, which can cause various postsynaptic effects. Neurotransmitters work locally and their actions are very fast.

Both hormones and neurotransmitters influence our thoughts and motivations, as well as our ability to learn and concentrate. However, neurotransmitters’ actions are short-lived while hormones act for longer periods of time. Furthermore, neurotransmitters can affect both voluntary actions (eating, bathing, walking) and involuntary actions (breathing, blinking). Hormones in the endocrine system always work involuntarily.

Curious Similarities

Research in the last couple of years has demonstrated that some hormones, work like neurotransmitters independently of their classical hormone actions. The most well-studied hormones are progesterone and estrogen, which are known as steroid hormones.

Steroid hormones are typically synthesized in the endocrine gland and bind to a receptor that then binds to a specific DNA sequence, affecting gene transcription. This process is a lengthy one, which means that steroid hormones work for a prolonged period of time.

However, Progesterone and estrogen are also synthesized in the neuronal circuit, specifically in the presynaptic terminal. They then bind to the membrane and intracellular receptors followed by neurotransmitter-like action, which is very fast and short-lived. These neurotransmitters-like steroids have multiple receptors. The steroid-receptor specific functions are not yet clearly understood.

Some well-studied neuroreceptors, like dopamine and serotonin are known to possess hormonal functions. Dopamine is a neurohormone released from the hypothalamus; its main function is to block the release of prolactin, another hormone, from the pituitary gland. As a neurotransmitter released from the central nervous system, it also has many functions including roles in cognition and motor activity.

Adrenaline and noradrenaline are two molecules that differ by one carbon atom. Adrenaline, which is produced by the adrenal gland, acts as a hormone. On the other hand, noradrenaline acts as a neurotransmitter in the central nervous system.

This is just a piece of a growing body of research suggesting that many hormones work as neurotransmitters and vice-versa. The next area of research here is to determine the receptor-specificity of these molecules to understand how their function may change depending on the receptor and mode of binding.

Source: The Biochemists

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Serotonin

Annamarya Scaccia wrote . . . . . . . . .

Serotonin is a monoamine neurotransmitter, a chemical nerve cells produce. It sends signals between your nerve cells. Serotonin is found mostly in the digestive system, although it’s also in blood platelets and throughout the central nervous system.

Serotonin is made from the essential amino acid tryptophan. This amino acid must enter your body through your diet and is commonly found in foods such as nuts, cheese, and red meat. Tryptophan deficiency can lead to lower serotonin levels. This can result in mood disorders, such as anxiety or depression.

What does serotonin do?

Serotonin impacts every part of your body, from your emotions to your motor skills. Serotonin is considered a natural mood stabilizer. It’s the chemical that helps with sleeping, eating, and digesting. Serotonin also helps:

  • reduce depression
  • regulate anxiety
  • heal wounds
  • Simulate nausea
  • maintain bone health

Here’s how serotonin acts in various functions across your body:

Bowel movements: Serotonin is found primarily in the body’s stomach and intestines. It helps control your bowel movements and function.

Mood: Serotonin in the brain is thought to regulate anxiety, happiness, and mood. Low levels of the chemical have been associated with depression, and increased serotonin levels brought on by medication are thought to decrease arousal.

Nausea: Serotonin is part of the reason why you become nauseated. Production of serotonin rises to push out noxious or upsetting food more quickly in diarrhea. The chemical also increases in the blood, which stimulates the part of the brain that controls nausea.

Sleep: This chemical is responsible for stimulating the parts of the brain that control sleep and waking. Whether you sleep or wake depends on what area is stimulated and which serotonin receptor is used.

Blood clotting: Blood platelets release serotonin to help heal wounds. The serotonin causes tiny arteries to narrow, helping form blood clots.

Bone health: Serotonin plays a role in bone health. Significantly high levels of serotonin in the bones can lead to osteoporosis, which makes the bones weaker.

Sexual function: Low levels of serotonin are associated with increased libido, while increased serotonin levels are associated with reduced libido.

Natural serotonin boosters

The following factors can boost serotonin levels, according to a paper published in the Journal of Psychiatry and NeuroscienceTrusted Source:

  • Exposure to bright light: Sunshine or light therapy are commonly recommended remedies for treating seasonal depression. Find a great selection of light therapy products here.
  • Exercise: Regular exercise can have mood-boosting effects.
  • A healthy diet: Foods that can increase serotonin levels include eggs, cheese, turkey, nuts, salmon, tofu, and pineapple.
  • Meditation: Meditating can help relieve stress and promote a positive outlook on life, which can greatly boost serotonin levels.

Source: Healthline

Want to Prevent Dementia? Follow these WHO New Guidelines

If you want to save your brain, focus on keeping the rest of your body well with exercise and healthy habits rather than popping vitamin pills, new guidelines for preventing dementia advise. About 50 million people currently have dementia, and Alzheimer’s disease is the most common type.

Each year brings 10 million new cases, says the report released Tuesday by the World Health Organization. Although age is the top risk factor, “dementia is not a natural or inevitable consequence of aging,” it says.

Many health conditions and behaviors affect the odds of developing it, and research suggests that a third of cases are preventable, said Maria Carrillo, chief science officer of the Alzheimer’s Association, which has published similar advice.

Since dementia is currently incurable and so many experimental therapies have failed, focusing on prevention may “give us more benefit in the shorter term,” Carrillo said.

Much of the WHO’s advice is common sense, and echoes what the U.S. National Institute on Aging says.

That includes getting enough exercise; treating other health conditions such as diabetes, high blood pressure and high cholesterol; having an active social life, and avoiding or curbing harmful habits such as smoking, overeating and drinking too much alcohol. Evidence is weak that some of these help preserve thinking skills, but they’re known to aid general health, the WHO says.

Eating well, and possibly following a Mediterranean-style diet, may help prevent dementia, the guidelines say. But they take a firm stance against vitamin B or E pills, fish oil or multi-complex supplements that are promoted for brain health because there’s strong research showing they don’t work.

“There is currently no evidence to show that taking these supplements actually reduces the risk of cognitive decline and dementia, and in fact, we know that in high doses these can be harmful,” said the WHO’s Dr. Neerja Chowdhary.

“People should be looking for these nutrients through food … not through supplements,” Carrillo agreed.

The WHO also did not endorse games and other activities aimed at boosting thinking skills. These can be considered for people with normal capacities or mild impairment, but there’s low to very low evidence of benefit.

There’s not enough evidence to recommend antidepressants to reduce dementia risk although they may be used to treat depression, the report says. Hearing aids also may not reduce dementia risk, but older people should be screened for hearing loss and treated accordingly.
Source: CBS


Read the WHO Guidelines Publication:

RISK REDUCTION OF COGNITIVE DECLINE AND DEMENTIA . . . . .


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Why You Should Eat Beans For Dessert

Kat Thompson wrote . . . . . . . . .

Here are all the places you might expect to find beans: on a Mexican plate lunch, covered in cheese and adjacent to enchiladas and rice; swimming in a pool of chili; or sweet-and-salty and piled on toast the way Brits and Aussies prefer in the AM. But beans, more often than not, are overlooked for a meal they absolutely shine in: dessert.

Growing up, I spent the majority of my weekends at the local Thai temple, where it was routine for me to buy a bowl of sticky mung bean pudding glazed with salted coconut milk to cap off my Thai lessons. The dessert, called tau suan in Thai, is also served in Singapore and China, where it is occasionally used as a dip for Chinese crullers or speckled with crunchy water chestnuts.

Mung beans are versatile, and present in a number of other Thai desserts. There’s luk chup, a mung bean confection shaped to look like traditional Thai fruits and vegetables and sealed in a shiny gelatin glaze. There’s also khanom mo kaeng tua, a baked mung bean custard comparable to flan that is topped with savory fried shallots. The yellow beans also find themselves in Vietnamese che bau mau, a parfait-like dessert layered with ice, coconut milk, pandan jelly, and another superstar in the world of dessert beans: red beans.

Red beans, which are sometimes referred to as adzuki beans, are prominent in both Japanese and Chinese desserts. It can be made into a paste, called anko in Japanese, which is then stuffed in mochi and moon cakes or slathered between honeyed pancakes in a dessert called dorayaki. In the Philippines, it’s included in shaved ice sundaes — alongside flan, scoops of ube and coconut ice cream, and jellies — known as halo-halo.

The flavor of red beans is earthy but naturally sweet and the texture, when blended, is smooth — almost like a sweet potato or yam that has been condensed into a tiny bean form. Red bean has also been used in ice cream, popsicles, and as a topping on fluffy domes of shaved ice. In fact, the flavor is so popular throughout Asia that McDonald’s has even plugged the paste within its famous, flaky pie crust in Hong Kong, Singapore, and Japan.

Sweets containing beans are not just a phenomenon that exist within Asia. Red beans make their way into habichuela con dulce, a creamy blend of beans, sweet potatoes, coconut milk, and evaporated milk from the Dominican Republic that is topped with cookies, raisins, and cinnamon and commonly eaten during Easter.

In southern states across the US, navy bean pie, an alternative to sweet potato pie, is quite popular. Associated with the Muslim African American community, the pie features a custard bean filling flavored with cinnamon and nutmeg. “One theory behind the bean pie’s potent symbolism is that it not only uses Muhammad’s beloved navy beans but is also believed to use them as a replacement for sweet potatoes, one of the most prominent symbols of traditional black cooking and a direct relic of the so-called ‘slave diet,’” wrote Rossi Anastopoulo for TASTE. “In some ways, swapping sweet potatoes for navy beans in a pie was akin to replacing one’s slave name with an X, as Muslim American historian Zaheer Ali has proposed.”

Beyond red beans, mung beans, and navy beans, black beans also make an appearance in a number of sweets. There’s black bean pudding soup with sago in a coconut milk broth (a Hong Kong classic), sticky rice studded with black beans and wrapped in banana leaves, as well as a black bean and rice pudding topped with coconut milk.

The reason that beans are so commonly found in desserts throughout the world have a lot to do with access to ingredients; every culture, no matter what corner of the Earth they’re from, has recipes that include beans in them. “Beans contain multitudes: They’re sturdy, reliable, versatile, an affordable vegetarian protein source,” notes The Cut. Why not add sugar to those beans and make a treat out of them?

It’s also not surprising that beans are highlighted in sweets from Asia, where the majority of people shy away from rich butter, milk, and dairy-based desserts. According to the U.S. National Library of Medicine, roughly 65% of adults struggle to digest lactose after infancy. That number is even higher for those of East Asian descent, where more than 90% of adults are affected. A simple solution for preventing a stomach ache from ice cream or creme brulee is to avoid those types of desserts entirely; bean-based desserts laced with coconut milk are not only lactose-free, but tend to be vegan, too.

If you’ve never before considered beans to be a remarkable ingredient for dessert, reconsider: it’s bean proven to make an excellent addition to any sweet treat.

Source: Thrillist

Sugary Drinks and Fruit Juice May Increase Risk of Early Death

Steven Reinberg wrote . . . . . . . . .

Most folks know that sugary drinks aren’t healthy, but a new study finds fruit juices are not much better.

In fact, consuming them regularly may help shorten your life, researchers say.

“Older adults who drink more sugary beverages, which include fruit juice as well as sodas and other sugar-sweetened beverages, may be at risk of dying earlier,” said study author Jean Welsh. She is an associate professor at Emory University School of Medicine in Atlanta.

“Efforts to decrease consumption of sodas and other sugar-sweetened beverages should also include fruit juices, and these efforts need to include adults as well as children,” Welsh said.

For the study, Welsh and her colleagues collected data on 13,440 men and women, average age 64, who were part of a large stroke study from 2003 to 2007. Among these participants, 71% were obese or overweight.

The participants were asked how many sugar-sweetened drinks they consumed. Over an average of six years, 1,168 of the participants died.

The researchers found that those who drank the most sugar-sweetened beverages — including 100% fruit juice — had higher odds of dying during the study, compared with those who drank the least of these.

Moreover, each additional 12-ounce drink increased the risk even more.

The report was published online in JAMA Network Open.

In the United States, about half of the population consumes at least one sugar-sweetened drink per day, said Marta Guasch-Ferre, a research scientist in the department of nutrition at Harvard T.H. Chan School of Public Health, in Boston.

“Most people are aware that sodas and other sugar-sweetened beverages — including soft drinks, fruit punch and energy drinks — are associated with weight gain and adverse health effects. But fruit juices are still widely perceived by many as a healthier option,” Guasch-Ferre said.

Evidence has shown that sugar-sweetened drinks are tied to an increased risk for diabetes, heart disease and obesity, she added. The evidence is less clear for fruit juice.

Whole juice contains some nutrients, and that may be beneficial for health, but they also contain relatively high amounts of sugar from natural sources, Guasch-Ferre explained.

Although fruit juices have been associated with an increased risk of diabetes and heart disease, whole fruits have not, she said.

Current recommendations suggest drinking no more than 4 to 6 ounces of juice per day, Guasch-Ferre said.

“Although fruit juices are not as harmful as sugar-sweetened beverages, consumption should be moderated in both children and adults, especially for individuals who attempt to control their body weight,” said Guasch-Ferre, who co-authored an accompanying journal editorial.

Fruit-based smoothies are commonly seen as healthier options. However, their ingredients can vary substantially and there is limited research on their health effects, she said. In addition, smoothies are usually very high in calories and so aren’t recommended as daily beverages. Vegetable juice is a lower-calorie alternative to fruit juice, but may contain a lot of salt.

“The current evidence suggests that water should be the preferred beverage, and the intake of other beverages such as tea or coffee, without sugar and creamers, should be chosen in place of sugar-sweetened drinks,” Guasch-Ferre advised.

Source: HealthDay


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