receptors – BioQuakes

Have We Discovered The Itchy Stitch?

On October 27, 2021

A Brand New Poison Ivy Vaccine is in the Works; here is What We Know So Far.

Vaccine: The word spoken and heard by most Americans at least ten times daily this past year, yet not usually preceded by “Poison Ivy.” Working at Duke University, biochemist Sven- Eric Jordt heads a team of researchers investigating pain and itch mechanisms, studying the unpleasant sensations of Toxicodendron radicans, better known as poison ivy. Jordt reveals that contact dermatitis (the red rash received from poison ivy) is usually treated by local doctors and rarely shown attention or mass funding. Author of ‘A Vaccine Against Poison Ivy Misery Is In The Works,’ Claudia Wells states, “given the toll in suffering and dollars, you would think serious attention would be paid to this worsening public health issue, you’d be wrong.” When pharmaceutical companies recognized more money was to be made on drugs for chronic skin conditions like eczema, they felt no need to research effective treatments on a temporary rash.

Having never personally contracted poison ivy, I cannot describe the exact feelings of pain or irritation, but to quote a good friend, “it would be less painful for my skin to be set on fire.” Now I must state that this friend did have an extreme reaction to poison ivy, they pitched their tent in a field of the poisonous plant, yet severe reactions are more common than most might assume. Every year 10 – 50 million Americans contract poison ivy and suffer for an average of 2-3 weeks. Research obtained in a six-year study at Duke University found that an increase of carbon dioxide, i.e., climate change, causes the poison ivy plant to produce a more potent allergenic form of Urushiol, the resin responsible for the rash. With increased concerns regarding climate change, it appears odd that Jordt is one of few who take this rash seriously.

Currently, the main treatment methods of antihistamines and cortisone cream do the rash very little justice. This is because our body’s reaction to Urushiol has no relationship to histamines, rendering antihistamines useless. In explaining this information to my dad, he agreed that all of the efforts recommended to him when he got poison ivy, a little less than two years ago, proved ineffective. To solve this, Sven Jordt and his colleagues began to analyze receptors that matched with proteins that showed inflammation from Urushiol.

In biology, receptors are proteins that receive signals by bonding with molecules known as ligands to send a specific message onward. A cell’s response depends on the types of receptors present, and each cell has its own number and type of receptor that allows them to act differently to various stimuli. Regarding poison ivy, Jordt and his team discovered that interleukin 33, an immune chemical in the body, is the main culprit behind the symptom of itchy skin. Jordt and his team of researchers are currently testing antibodies against IL-33, such as ST2, in primary sensory neurons. If ST2 could effectively block IL-33’s receptors, the necessity to scratch would virtually disappear. “This is all very new information,” Dermatologist Brain Kim, co-director of the Center for the Study of Itch & Sensory Disorders at Washington University in St. Louis, states. In the past, scientists believed that both the rash and itch from poison ivy were triggered by the immune system’s T cells. Further studies, however, have shown that the inflamed rash and itch sensation come from two different places entirely; It is believed “T cells do cause the inflamed rash of poison ivy but that these other pathways provoke the itch.” (Brian Kim)

While human research has been challenging to complete due to a lack of study funding, a compound called PDC-APB, a small synthetic molecule derived from active urushiol components, is being developed into a vaccine to prevent painful contact dermatitis.

As stated earlier, I have thankfully never had poison ivy myself, and I would like to keep it that way. As someone who goes on Sunday hikes through the woods with my family, contracting poison ivy is a constant fear of mine and leaves me wearing pants while walking in the July heat. I think a vaccine would be a fantastic option for someone who spends much of their time in places of possible poison ivy. The only question would be, is this the solution to our itchy problem?

Obesity Related to the Brain

By brookioles

On November 28, 2016

In Student Post

Lauri Nummenmaa has done research the connects obesity to the brain. This research shows that people struggling with obesity have a lower amount of μ-opioid receptors available for binding in the brain. (To learn more about μ-opioid receptors click here.) Due to evolution, our brains are still “wired” to search for food and nutrients. Since eating gives off a sensation in the brain, related to the opioid receptors, people with fewer receptors that are able to bind will therefore eat more to make up for the loss in sensation. This reaction is the same as a reaction to an addiction would be, causing more neurotransmitters to be secreted. The next step that scientists are taking is to discover whether being obese causes a lack in opioid receptors, or if a lack in opioid receptors, caused by another source, is what causes obesity. One test that scientists did was testing μ-opioid receptors in people that had bariatric surgery. Bariatric surgery causes more receptors to work again, shown by the fact that scientists could not distinguish between the μ-opioid receptors or healthy people and the μ-opioid receptors of people who had the surgery.

Some body fat, however, is helpful to the brain. This article describes that “fat tissue in the bodies of mice releases an extracellular form of nicotinamide phosphoribosyltransferase (eNAMPT), an enzyme that travels to the hypothalamus, and gives animals energy during fasting.” (To learn more about eNAMPT click here.)

This photo shows how a neurotransmitter is sent from neuron to neuron generally.

(Link to Photo Page and Link to Licensing Page)

Oh the Irony: Spice Receptors Responsible for Cold Sensations

By nicheloss

On November 17, 2014

In Student Post

For some people, experiencing cold temperatures translates to an extreme and painful sensation, rather than just “feeling chilly”. This type of pain can even occur at milder temperatures of 68°F and below. When studying the body’s mechanism responsible for connecting cold and pain, researchers at Lund University in Sweden recently discovered that the receptor involved here is the same receptor which reacts to substances in garlic and mustard.

There has been lots of research regarding the connections between pain and irritant substances in mustard, garlic and chili. When consumed in mass amounts, these spices can cause burning sensations, rashes, swelling, and when exposed to the eyes, crying. The substances in the spices affect nerves involved in the pain system and are activated by inflammation. In the case of the garlic and mustard receptor, the Lund research team noted the way powerful substances in the garlic and mustard irritated the nerve cells 10 years ago. These receptors are found throughout the body, in places such as the skin, bladder and gut. TRPA1 is the ion channel, associated with sensory processes, activated by garlic extracts and mustard oil. with Now, the scientists have extended their research to prove that this garlic and mustard receptor also responds to cold.

By extracting the human receptor protein and inserting into an artificial cell membrane, the Lund scientists were able to see its reactions to cold. The scientists executed their experiment hoping get a better understanding of the body’s temperature senses and help for cold allodynia sufferers. People with chronic pain or diseases often experience problems affecting the nervous system. For instance, cancer patients undergoing chemotherapy treatments can experience the side-effect of becoming over-sensitized to cold. The pain experienced by patients and the reaction for the garlic and mustard receptor both begin at relatively mild temperatures.

Drug companies are attempting to address this issue by developing drugs which will block the receptors, hopefully reducing the inflammation side effects and general pain. The Lund team believes this application will also relieve the pain caused by cold. The garlic and mustard receptor reacts to chemical substances acting as airway irritants. To address this issue, a new plausible solution of a drug which helps those affected by perfume, smoke and other irritants is believed to also help people suffering from over-sensitizing cold in their airways.

The connection of the garlic and mustard receptor to cold helps us further understand the precision and specificity of the our body’s abilities in temperature sensing. Substances in spices (notoriously hot and well, spicy) can react in ways to bring about extreme pain from over-sensitivity to cold. It’s wild that the body’s sensory neurons can share receptors and cause similar reactions to very different triggers (spice substances and the cold). It’s pretty amazing that medication is being developed to block the receptors for both substances, lessening the pain and inflammation for these seemingly polar issues. It turns out that science, involved in even the tiniest receptor, really does connect everything.

Sources:

http://www.sciencedaily.com/releases/2014/11/141113085154.htm

http://www.ncbi.nlm.nih.gov/books/NBK5237/

http://www.achenet.org/resources/allodynia_when_touch_hurts_but_shouldnt/

Photograph :

Images by John ‘K’

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: receptors

Have We Discovered The Itchy Stitch?

A Brand New Poison Ivy Vaccine is in the Works; here is What We Know So Far.

Obesity Related to the Brain

Oh the Irony: Spice Receptors Responsible for Cold Sensations

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