Cobbers on the Brain – Page 121 – Student Commentary on the Neurological Sciences

Vapor or Smoke? Pick Your Poison.

Posted on April 5, 2016 by / 0 Comment

In 1965, according to the CDC, 42% of American adults were considered regular cigarette smokers. Today, with the help of scientific publication and a large governmental push to expose the negative effects of smoking, that number is at 16%. In just over 50 years, this decline is a huge accomplishment and many lives are saved because of it. That being said, there is a current trend rising in the world of nicotine: electronic or E-cigarettes.
E-cigarettes are battery operated devices that deliver nicotine (and often flavoring) to an individual without producing tobacco smoke and instead a water vapor is released. With this method of smoking, the risk of second-hand smoke is eliminated, but there are huge concerns still about whether or not this pure nicotine can still have negative health effects for the person who ingests it.
In the brain, nicotine binds to receptors called nicotinic acetylcholine receptors or nAchRs. Multiple exposures to nicotine causes up-regulation of these receptors which increases their affinity for the drug and addiction is the result. Several studies have be done to investigate possible negative effects of this interaction between repetitive nicotine exposure and these nAChRs so explore possible neuronal damage that nicotine addicts may be experiencing.
One area of the brain affected is the ventral tegmental area (VTA) which is largely responsible for dopamine, a neurotransmitter that corresponds to pleasure and reward, release. When nAChRs are activated by nicotine, dopamine is released in the VTA and studies have found that continuous stimulation of these receptors from nicotine has the ability to desensitize this response. Clinically, this could result in a decreased ability to experience pleasure from this area of the brain.
With nicotine use, there is also the concern of cross-sensitization between it and alcohol. Like nicotine, nAChR’s are the receptors that alcohol interacts with. The concern with cross-sensitization and these drugs is that being addicted to one drug may make you more likely to be addicted to the other. Studies on this phenomenon have mixed findings, but it is confirmed that lab animals addicted to nicotine consume more alcohol when provided it compared to animals who are not addicted to the drug. Because these drugs act on the same receptors, cross-sensitization is an important aspect to consider as one studies how drug addiction works.
In conclusion, though E-cigarettes eliminate the worry of second hand smoke and the tobacco-related toxins that cigarettes have, people are still left wondering: Can the nicotine from E-cigarettes still be damaging for a person? Also, current testing of the cartridges for E-cigarettes if showing that many of them release vapors containing carcinogens and other toxins. Long story short, I believe that there are two reasons that people who are addicted to nicotine should be hesitant about E-cigarettes.

It still in unclear how long-term exposure to nicotine can damage the brain or predispose the brain to new addictions and
It is still unknown what the exact chemicals in E-cigarettes are and how those chemicals can damage the body.

The fight against cigarette smoking is a battle well fought by the government and health professionals alike, but it’s important to continue to use our expanding scientific knowledge to protect the public from new threats to our health that are being developed every day.

Health

LTP and how learning effects abuse potential

Posted on April 5, 2016 by / 0 Comment

There are numerous ways our brain “learns” and one of the main ways, and most common, is called long term potentiation (LTP).
What happens is in certain areas of the brain glutamate (the CNS’s main excitatory neurotransmitter) gets released in response to some stimulus. Glutamate binds to an AMPA receptor in the post synaptic neuron which allows sodium to flood the neuron and fire an action potential which proceeds to send the signal for the initial stimulus. This could be anything from hearing a noise or smelling a flower to thinking about an event or trying to memorize a phone number.
When the learning occurs is when that initial stimulus fires over and over again causing a lot of Glutamate to be released and lots of post synaptic binding to AMPA receptors occurs resulting in a large amount of sodium to enter the post synaptic neuron.
Within this post synaptic neuron there are also NMDA receptors. NMDA receptors are both ligand gated and voltage dependent receptors. The NMDA receptors have a magnesium ion lodged in the middle of it. When there is enough sodium in the post synaptic neuron the magnesium ion gets repelled outside of the neuron allowing calcium to enter the post synaptic neuron.
Once in the cell, calcium induces activity in enzymes in the cell. Calcium activates calmodulin which activates CAM-KII, a kinase which will phosphorylate a dendritic vesicle. This dendritic vesicle has an AMPA receptor lodged in the membrane waiting to be activated. The phosphorylation activates it and the vesicle places the AMPA receptor into the post synaptic neuron’s membrane.
Now the post synaptic neuron has more receptors making it easier for the neuron to fire. This is also known as learning.
When it comes to drugs of abuse, this pathway has a very important role. An example could be that this pathway is in the reward center of the brain. The initial stimulus could be a cigarette. This ultimately releases dopamine into the nucleus accumbens. The person really liked that feeling so they start smoking a lot more causing that over stimulation of the neuron making the post synaptic neuron “better” at firing.
Now that learning has occurred, it only takes the smell of a cigarette to trigger this action potential to get the same feeling as one cigarette took the first time. This is an example of craving.
LTP is a very important CNS pathway whether it is for memorizing a fact for an exam or causing craving troubles in an addicted person.
I think it is one of the most interesting topics because scientists have found a way to literally see dendritic growth from LTP meaning if the growth was removed, the memory would be lost. This could be incredible for future treatments for certain disorders such as PTSD.

Artstract:

Image citations:
http://thebluediamondgallery.com/l/learning.html
http://www.nature.com/articles/srep01957

Uncategorized

Cheers to Ethanol and Nicotine is the Devil: Why We Need to Take a Second Look at the Glories of Ethanol

Posted on April 5, 2016 by / 0 Comment

Everyone knows the horrors of cigarettes. We’ve all seen the commercials of the premature aging, the inevitable lung cancer, the life draining chemicals that come with cigarettes. We’ve heard the threats of chewing tobacco—seen the story of the man who lost half of his jaw to mouth cancer.

(From: http://designbump.com/anti-smoking-advertisements/)

We’re all aware and rightfully afraid of the power of addictive nicotine and the cocktails of chemicals it is mixed up with.

But what about ethanol?

We love ethanol—beer, wine, cocktails, happy hour. We can’t seem to fathom a party or holiday without it. We idolize a good time in the media by complete loss of control and the endless flow of ethanol.
However, the two drugs share commonalities we never seem to give them credit for. The brain chemistry alterations of both nicotine and ethanol are very likely the same in many ways, and addiction of both can be extremely detrimental to our health. It’s time we reexamine the ways we look at ethanol.

The Relationship

Ethanol and nicotine act on the same receptors in the brain, the neuronal nicotinic acetylcholine receptors (nAChRs).

Nicotine activates these receptors and leads to receptor desensitization—meaning the tolerance for nicotine increases with each dose. This results in more receptors present, leading to a dependence upon nicotine to continue to simulate them—this is a major proponent in nicotine’s addictive properties.
Ethanol also is linked to these receptors. It potentiates these receptors leading them to be active more often. This increased activation then leads into the cycle that is observed with nicotine addiction. Ethanol does not activate the receptors in the same manner as nicotine does, however, and this is likely a reason it is considered less addictive.
Along with this this receptor commonality, the patterns of addiction are the same and the areas of the brain the two drugs effect overlap tremendously. These brain structures include: the ventral tegmental area, the nucleus accumbens, the prefrontal cortex, the striatum, the amygdala, and the hippocampus.
All of these major brain regions are affected by both drugs and may explain the cross-sensitization observed between the two—meaning that once a person is addicted to one they are more likely to get addicted to the other.
Ethanol begins to look a lot like nicotine in the brain. Why then do we paint such a black and white picture of the two drugs?

(#artstracts)

Time for Reexamination

We can argue that anti-alcohol rhetoric is in the media, too. We have seen a dramatic increase in campaigns against drunk driving in recent decades. But, there is little knowledge or publicity about the effects of ethanol on our overall health and brain chemistry.
There are surely no shrunken, deteriorated brain posters displaying ethanol dangers next to the smoking lungs harmed by chronic cigarette usage.
Granted, the lines of alcohol addiction are blurrier, and the fact of the matter remains that alcohol is less addictive than nicotine. But this should not be our scapegoat for research into the effects of ethanol abuse.
It is notably easier to drink one beer per week than to simply smoke one cigarette. But why is that? Because these two drugs are so linked in their brain chemistry—affecting the same neuronal receptors, displaying the same development pathways of addiction, targeting the same brain structures—there is need for further research into these connections.
In the research our class conducted on this topic in the past week we learned a lot about the effects of nicotine, and learned very inconclusive results about the effects of ethanol—simply because there is significantly less research done on this drug.
It’s time we stop saying cheers, and start investigating the links. While it may be true that ethanol is less of a threat to health, it is extremely hypocritical to raise one drug up so highly above the other while scientific links continue to emerge.

Uncategorized

Why Nicotine is so Hard to Quit

Posted on April 5, 2016 by / 0 Comment

The amount of people smoking cigarettes in the United States has been on the decline since it was first recorded in 1965, and is continuing to decline. This is largely because of the vast amount of research that has been put into showing how many negative health effects that smoking has on a person, as well as being an expensive and addictive habit. You may be looking for information on how to rid either yourself or someone you know from cigarettes, which “harms nearly every organ in the body” and is responsible for almost one in five deaths in the United States, usually because of premature deaths related to smoking-related diseases.
Many people start out at a young age and later on seek to quit for various reasons, but that can be very difficult because of the neuroplastic changes that occur because of long term nicotine consumption, a chemical in cigarettes and other tobacco products, which acts on receptors found in the brain. In fact, one neuronal receptor, the nicotinic acetylcholine receptor (nAChR), is named for its activation by nicotine. nAChR is found extensively throughout the brain on neuronal cells and plays a significant role in brain plasticity.

Nicotinic acetylcholine receptor. Acetylcholine (found in the brain naturally) and nicotine (found in tobacco) both bind to this receptor and activate it. — Nicotinic acetylcholine receptor (nAChR). Acetylcholine (found in the brain naturally) and nicotine (found in tobacco) both bind to this receptor and activate it, strengthening the future activity of the neuron that is activated.

Brain plasticity means that the brain can physically change it’s patterns of neuronal connections in response to various types of inputs it receives, such as learning, the environmental stress, or drugs. The brain regulates which neurons connect and how strongly they interact, leading to behavioral changes in a person.
This is where nicotine plays its role as an addictive substance, because when the nAChR is activated by nicotine, it initiates “long term potentiation,” the strengthening of neuronal connections in response to stimulus. Addictive learning is involved with the act of smoking cigarettes because nicotine directly activates the neurons involved with performing this behavior, and the reward system is activated. The neurons that are activated while a person smokes a cigarette are strengthening their output because of the effects of nicotine. This is why certain emotions, locations and smells (like smoke) can trigger a person’s desire to smoke. Even the hand motions of smoking and holding a cigarette will activate the neurons that have been over-strengthened and create a reward response in the brain.

prp — *The reward pathway is activated by nicotine and causes addiction with enough smoking. Dopamine is released in the nucleus accumbens.*

Looking at the trial of quitting this habit from a neurological perspective reveals why quitting is so hard. A person who has smoked cigarettes for a large portion of their life has rewired their brain so that they need cigarettes in order to feel good, because that is a major part of their reward system (dopamine release in the nucleus accumbens). The brain seeks activation of the reward system and creates negative emotions to get the addict to perform the action and resolve its stress. Luckily, there are treatment options like medicine, nicotine replacement, and therapy to make it easier. Talk to your doctor for options that can assist you in your journey towards recovery.

Uncategorized

Behind Schizophrenia: Research and Understanding

Posted on March 23, 2016 by / 0 Comment

This past week, the Concordia Neurochemistry Class talked about the neurology behind Schizophrenia, which is a long-term, developmental mental disorder that involves a dissociation between thought, emotion, and behavior.
This dissociation leads to symptoms such as hallucinations, delusions, withdrawal from reality, and a sense of mental fragmentation.

Similar to Autism, the diagnosis of Schizophrenia lies on a spectrum. Some people are able to function well in society while having this disorder, and some are unable to. Those who are very low functioning often live in group homes or hospitals.
One of the topics we talked about during the Friday discussion was the treatment of Schizophrenia, and where we think the research should focus on. Being such a “reactive” instead of “proactive” mental-health system, a lot of the research and funding is going towards treating those who are currently diagnosed.
Some people agreed with that. It is—for obvious reasons—essential to help those who are already trapped by such an inhibiting disorder. It is important to make sure that they are receiving adequate care and have access to current antipsychotic medication.

However, we also talked about the importance of nipping it in the bud by focusing research on neurodevelopment and understanding how the brain develops and, therefore, what causes the malfunction in neural communication that leads to disorders such as Schizophrenia.
Right now, there is research on certain hypothesis and theories regarding Schizophrenia that may explain the cause of the symptoms of the disorder.
The oldest and most established is the Dopamine Hypothesis.

Dopamine is a neurotransmitter that is a precursor for adrenaline, and is part of the reward pathway in the brain. That means that it is the neurotransmitter that is released when something “feels good.”
The Dopamine (DA) Hypothesis started off as stating simply that there is an increased amount of Dopamine in the brain of someone with Schizophrenia. Now, thanks to Neuroimaging techniques and advanced research, the DA Hypothesis has even more support.

Studies since the ‘90s have been focused on pinpointing the exact impact that Dopamine has on Schizophrenia. Some had found that the most prominent Dopamine receptor is D1, and Dopamine is unable to properly bind to those receptors, causing an influx in DA in areas of the brain such as the prefrontal cortex, which would explain some of the cognitive symptoms of Schizophrenia such as inhibited working memory and attention deficits.
This influx of Dopamine then causes a misfiring in a signaling cascade, which leads to a lack of Dopamine in the mesolimbic system. This is correlated with the negative symptoms of Schizophrenia, which include social withdrawal, lack of emotion, and inability to experience pleasure.
Our increasing knowledge about Dopamine and Schizophrenia means that we have a potential explanation for Schizophrenia symptomology, but what’s next?

By encouraging research on development and the direct etiology of neurodevelopmental disorders such as Schizophrenia, we will be able to identify what causes the abnormal Dopamine amounts in the brain, and how we can better treat, prevent, and even cure this disorder.

Disease

Wnt signaling pathway in schizophrenia

Posted on March 23, 2016 by / 0 Comment

Schizophrenia is a fairly common psychiatric disorder. It is currently top ten disabling conditions worldwide for young adults. It is known for causing positive symptoms including hallucinations, delusions, and racing thoughts. However, it also has negative symptoms attributed such as cognitive disfunction.
Effective therapeutics for schizophrenia is difficult to come by mainly because of a lack of understanding of the disease. The most popular hypothesis is that schizophrenia is a developmental brain disorder causing a disfunction in neural connections. The exact area of the brain this is happening is a bit of a gray area, but from the symptoms it is thought to occur mainly in the pre-frontal cortex and the basal ganglia (the main dopamine output center in the brain).
Recent research has found Wnt signaling in the brain may have a significant role in schizophrenia etiology. Wnt signaling starts out by Wnt protein binding to a frizzled receptor (FZ) which causes an activation of the Disheveled (Dvl). This molecule breaks up the destruction complex which would have inhibited β-catanin, an important molecule in gene transcription. Another part of the puzzle is dopamine signaling. Schizophrenia patients have an increase in dopamine signaling which results in the inhibition of AKT enzyme which would have inhibited the destruction complex. Schizophrenics were also found to have a smaller number of AKT proteins which again, leads to an activation of the destruction complex and ultimately, a decrease in β-catanin activity resulting in a loss of gene transcription.
There are a few treatments that target certain areas of this signaling process, but many have proven ineffective such as Lithium. Lithium directly inhibits GSK3β, a key player in the destruction complex. However, for whatever reason it has shown ineffective for a majority of schizophrenic patients.
Anti-psychotics target the dopamine signaling in this process and has proven effective, however new treatments are needed for not all antipsychotics were effective in treating schizophrenia.
This research has opened a new door for schizophrenia treatments. With the discovery of the Wnt pathway’s role in schizophrenia, new drugs can be synthesized and possibly more effective treatments can be discovered.
Artstract:

Image citation:
https://www.emaze.com/@ALFWTCCI/Schizophrenia

Disease/Health

Understanding Schizophrenia

Posted on March 22, 2016 by / 0 Comment

When people think of brain disorders, they’ll think of the more common diseases but not schizophrenia. Parkinson’s Disease has Michael J. Fox and Muhammad Ali to help raise awareness of the disease. Alzheimer’s has been more commonly observed in older patients and funding for it has been steady. Schizophrenia, on the other hand, has been quiet with its effects.
Schizophrenia affects about one percent of the population, so 1 out of 100 people have the illness. There are three categories symptoms can be placed in. Positive, which contains the symptoms most would associate schizophrenia with, hallucinations, delusions and thought disorders. Negative, associated with behavior and emotions, reduced feelings of pleasure in life and having difficulty beginning and finishing activities. Cognitive, changes in memory and thinking, having troubles focusing and problems with their working memory.
Currently, there are only effective treatments for schizophrenia, such as anti-psychotics or psycho-social therapies. These treatments only help reduce the symptoms of the positive nature, and not the other two categories. The exact schizophrenia is still unknown, but by continuing research of the illness will be beneficial in finding a cure.
New research has shown the Wnt pathway can be useful in finding a cure for schizophrenia. The Wnt pathway is essential for neural development and circuit functioning. Anti-psychotics inhibit dopamine receptor. These types of drugs are the norm for treating schizophrenia, but by looking into another pathway associated with schizophrenia a cure can be found.

Glycogen synthase kinase (GSK3β), which regulates β-catenin. β-catenin is necessary for gene transcription, when phosphorylated causes proteasome, instead of gene transcription and reduces its amount in the cell. The disrupted signaling may play a critical role in schizophrenia.
Wnt is a signaling pathway that interacts with GSK3β, as well as dopamine too. By looking into the different signaling pathways to GSK3β, a cause for schizophrenia may be found. This will lead to a cure to be found for a disease with harsh effects on the human.

Disease

Schizophrenia: A New Possible Target for Drug Development

Posted on March 22, 2016 by / 0 Comment

Mental illness can be quite a burden for anyone affected by one of its many forms. Come mental health diseases such as schizophrenia, bipolar disorder, and depression devastate lives for new people every day. Among them, schizophrenia is one of the most severe and tends co-occur with depression. It is so devastating because its sufferers lose touch with reality and are likely to attempt suicide. Symptoms of schizophrenia include abnormal thinking, loss of contact with reality, hallucinations, delusions, inability to focus, and more.
Without any way to cure this disease, there are large costs for the person with schizophrenia, their family and society. The person affected loses their ability to enjoy life and to even function, while the family has to sit by and watch them suffer without having any way to help. When someone is disconnected from reality and truly believe that the people on T.V. are plotting to kill them, the only thing one can do it seek out the help of doctors and the most prescribed medications for schizophrenia: antipsychotics.
Antipsychotics are a class of drugs used primarily for treating schizophrenia, and are relatively successfully at eliminating the positive symptoms such as hallucinations and delusions, but they do not help with the negative symptoms: Flat affect, reduced speaking, reduced pleasure and focus. These medications do not cure schizophrenia, they only make life more manageable. They are very helpful, but research is still heavily involved in finding the underlying cause of schizophrenia to possibly prevent it from happening in the first place.
Even thought schizophrenia is typically diagnosed in a person’s early 20s (when they first start having the obvious symptoms: delusions and hallucinations), many researchers believe that schizophrenia is a developmental disorder in which neurons do not correctly associate with each other through their connections of axons and dendrites.

A neuron and its connection to another neuron with the synaptic terminals. Neurotransmitters are released from the synaptic terminals and they act as a signal for the next neuron.

Through much more data and analysis of how antipsychotics work for schizophrenia, a new and exciting mechanism is being explored for the treatment of schizophrenia. Antipsychotics work by blocking the over-activation of dopamine receptor D2. The “Wnt pathway” of neurons is involved in signaling within the cells of people and facilitates normal brain development for people. For people with schizophrenia, it is now thought that this pathway is not activated enough for normal development. Wnt works normally, but its effect on another protein important in neuronal development – GSK3-beta – is reduced because of too much dopamine signaling.

A homemade picture of a cell (the larger circle) and how the Wnt pathway and the D2 dopamine receptor affect development in the brain.

By targeting this pathway, the development of new drugs that treat all the symptoms of schizophrenia could be just around the corner.

Disease/Health

Filling in the Blanks of Schizophrenia

Posted on March 22, 2016 by / 0 Comment

Schizophrenia is a disease of many known and many unknown variables. For researchers, the general public, people living with the disease, and their loved ones, these knowns and unknowns can be very frustrating. Everyday, people question how schizophrenia develops, what is happening in the brain, how to treat it, and how much it impacts daily life.

The Known

Affecting about 2.6 million adults in the United States, schizophrenia is a mental disorder that presents in a person’s late teens to early 20s. With schizophrenia, there are often positive, negative, and cognitive symptoms. Positive symptoms often respond well to anti-psychotic medication and include hallucinations, delusions, and disordered thoughts and speech. Negative symptoms are more difficult to treat and include lack of emotion, decreased motivation, inability to experience pleasure and other similar mood changes. Cognitive deficits from schizophrenia are considered to be the core of the disease and are associated with troubles with memory, information processing, and decision making skills.
Learning about and witnessing this crippling disorder make the scientific and general communities interested in how to prevent and/or cure schizophrenia. It is known that dopamine, an excitatory neurotransmitter, levels are high in people with schizophrenia and dopamine excess is the target of many anti-psychotics which helps with the positive symptoms explained above. One major problem with the treatment for schizophrenia is that it is very difficult to treat the negative and cognitive symptoms The slowed advancements in this field are the result of the lack of understanding exactly how this disease impacts the brain. With the inability to fully understand the disease comes the inability to treat or prevent it.
Science has discovered many possible causes for the development of schizophrenia including genetic predisposition, infection during fetal development, and many other developmental abnormalities, but the cause is likely a combination of a person’s biological makeup and various events that happen during their development.

The Unknown

In the brains of people living with schizophrenia, there is a pathway called the WnT and GSK3 signalling pathway that researchers have found to have a major role in this disease.This pathway may offer explanation or treatment for more symptoms associated with the disease. WnT signalling is important in neurons because the activation of WnT receptors prevents the destruction of transcription factors that are necessary for proper cell development and function. When this pathway is disrupted, as it seems to be in schizophrenia, gene transcription in cells is inhibited. This means that this disrupted signalling pathway is a key factor in the development of symptoms.
This pathway is a possible explanation for the symptoms of schizophrenia beyond the hallucinations, delusions, and other positive symptoms. Researchers are trying to develop drug treatments that could minimize the damaging effects that this pathway has on neurons. Though drugs targeting the WnT pathway are still in their earlier stages, the idea of their success is promising. Treatment for the entire spectrum of schizophrenia symptoms could mean a much better quality of life for people living with the disease and those around them as well. Further understanding of this pathway also could help pinpoint the causes of schizophrenia and aid to eventually lower the number of people affected by this debilitating disorder.
Once again, I’m amazed and the idea that researchers are coming closer to understanding this seemingly impossible disease makes me love science even more.

Community/Disease/Health/Uncategorized

Let's Talk About Schizophrenia

Posted on March 22, 2016 by / 0 Comment

The Treatment Advocacy Center states that 1.1% of the world population is affected by schizophrenia and it is estimated that 40% of people with schizophrenia go untreated. Some symptoms of schizophrenia include delusions and hallucinations, changes in emotions movements and behavior, alterations of senses, an altered sense of self and the inability to sort and interpret what is going on.

There are numerous changes in the brain with schizophrenia, but not one specific condition that can be measured for diagnosis. The disease must be diagnosed by a measure of its symptoms. There are high functioning patients with schizophrenia who are able to carry on a mostly normal life while others must be hospitalized.

Schizophrenia is a brain development disorder, so it is difficult to prevent because we don’t see the effects until it has already progressed. There are studies that show that infections during pregnancy may disrupt fetal brain development which increases the risk of schizophrenia.

In the article we talked about this week found the main problem with schizophrenia is not enough Wnt signaling and overactive dopamine in the brain. The combination of these two cause increased phosphorylation of β-catenin. When β-catenin is phosphorylated it has no positive effects on the brain.

Wnt proteins are produced by wnt genes in the body and are used all over the body, many of the proteins are organ or tissue specific. Evidence of increased dopamine production as well as increased ability for dopamine to interact with its receptor have been a part of discovering dopamine’s role in schizophrenia.

β-cateinin is used across the body for cell-cell adhesion and gene expression. In schizophrenia there is not enough β-catenin, but many cancers are associated with the over expression of β-catenin.

The best thing we can do to help with the research in Schizophrenia is become informed. The more we talk about it, the more aware we will be about the symptoms, prevention, and treatments.