Foundational Neuroscience Essay

Foundational Neuroscience Essay

Foundational Neuroscience

Explain the agonist-to-antagonist spectrum of action of psychopharmacologic agents, including how partial and inverse agonist functionality may impact the efficacy of psychopharmacologic treatments.

The agonist-to-antagonist spectrum is a crucial example of pharmacodynamics, the study of the mechanisms, and the effects of medications within the body. Foundational Neuroscience Essay The agonist spectrum constitutes full agonists, partial agonists, antagonists, and inverse agonist actions (Stahl, 2021). In pharmacology, agonists are molecules that combine with receptors on a cell to trigger a physiological reaction, also known as a biological response, while antagonists are substances that stop the action or effect of another substance. However, antagonists’ activity is determined by the presence or absence of agonists.

Psychotic drugs interact with neurotransmitters, leading to full signal transduction due to full receptor stimulation. Partial agonists have a minimal stimulation effect compared to full or natural neurotransmitters, whereas inverse agonists blocks agonists, reducing their activity below baseline in the absence of agonists. Therefore, partial agonists can help achieve a suboptimal response in the absence of natural neurotransmitters or reduce the overstimulation of receptors in the presence of excess natural neurotransmitters. On the other hand, inverse agonists play a crucial role in reducing the negative intrinsic activity of psychotic drugs by binding to receptors and stabilizing them Foundational Neuroscience Essay.

Compare and contrast the actions of g-couple proteins and ion-gated channels.

G-couple proteins and ion gated channels transmit signals in a cell. The G protein-coupled receptors activate the G protein (guanine nucleotide-binding proteins), a signal transduction protein, which helps recognize substances outside the cells and transmits signals across the cellular membrane (Stahl, 2021). Signal processing is crucial for cellular responses, including gene transcription, cellular growth, and communication. Consequently, signal transduction and response help the body adjust and adapt to environmental changes. An example is the body’s response to anxiety through increased heart rate. Conversely, ion channels regulate the flow of ions. Ion channels are pores that regulate ion flow through the impermeant cellular membrane (Stahl, 2021). As a result, the ion channels facilitate ion flow to attain equilibrium depending on membrane potential and ion concentration differences across the membrane.

Explain how the role of epigenetics may contribute to pharmacologic action.

Epigenetics is central to modern pharmacology considering its role in investigating the interaction between human genes and environmental risks. Kular (2018) define epigenetics as meiotically and mitotically heritable changes that affect gene expression without variation in the DNA sequence. In this regard, epigenetic processes are not genetic and are broadly influenced by the environment and cell division. The resultant epigenetic mechanisms are responsible for instructing cells to interpret genetic and environmental signals and respond appropriately Foundational Neuroscience Essay. The process relies on the biochemical modifications of the human genome to enhance its stability and perpetual phenotypic adjustment of daughter cells. In psychopharmacology, epigenetics and its sensitivity to environmental factors, stability, and reversibility is critical in understanding and treating mental health conditions

Explain how this information may impact the way you prescribe medications to patients.

Most psychotic drugs in clinical practice interact with neurotransmitters. Psychotic drugs interact with the G-protein-linked receptors and neurotransmitter ligands (Stahl (2021). Therefore, understanding the interactions of psychotic drugs with the molecular sites and their impact upon transmission is crucial in determining the therapeutic effects of a psychotic drug and the potential side effects. Foundational Neuroscience Essay Equally, knowledge of epigenetics is critical in understanding the epigenetic side effects of common pharmaceutical drugs (Tzika et al., 2018). Such drugs may have inhibitory effects on epigenetic changes crucial for body functions. For example, the antihypertensive hydralazine inhibits DNA methylation.

 

References

Kular, L., & Kular, S. (2018). Epigenetics applied to psychiatry: clinical opportunities and future challenges. Psychiatry and Clinical Neurosciences, 72(4), 195-211. https://doi.org/10.1111/pcn.12634

Stahl, S. M. (2021). Stahl’s essential psychopharmacology: neuroscientific basis and practical applications. Cambridge university press.

Tzika, E., Dreker, T., & Imhof, A. (2018). Epigenetics and metabolism in health and disease. Frontiers in genetics, 9, 361. https://doi.org/10.3389/fgene.2018.00361

 

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19 days ago
Foundational Neuroscience EssayNdidi-Amaka Onyema 
RE: Foundational Neuroscience – Response #2
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Hello Carline,

Further to your point about applying an understanding of the concept of G proteins, GPCRs, and ion gated channels to practice by the PMHNP, I came across this interesting article by Boczek et al. (2021). Their article looked at the role of GPCRs and calcium signaling in the treatment and management of schizophrenia. They noted that GPCRs are involved in the development and progression of schizophrenia. They also noted that they are the most common targets for antipsychotic drugs as you also noted above. For instance, the GPCRs for serotonin, dopamine, adrenaline, and glutamate are targets for antipsychotics. The study also implied that dysfunctions in the frontal and limbic systems of the brain are behind the negative and positive symptoms associated with schizophrenia. Foundational Neuroscience Essay Given that the disease is severe with an unknown etiology and also given that extensive research has been devoted to the role of neurotransmitters in this ailment (dopaminergic theory), it has been discovered that the neurotransmitters involved act through GPCRs. This concept of GPCRs and ion gating (calcium signaling) coupled with epigenetics and environmental factors has opened up a new area that will target working around the dysfunction in the neurotransmitter system in these patients to arrive at a line of medications that may effectively treat the condition. This is a new field that is evolving at the neurotransmitter and receptor level and looks like it is going to transform psychopharmacology in a big way.

Boczek, T., Mackiewicz, J., Sobolczyk, M., Wawrzyniak, J., Lisek, M., Ferenc, B., Guo, F., & Zylinska, L. (2021). The Role of G Protein-Coupled Receptors (GPCRs) and Calcium Signaling in Schizophrenia. Focus on GPCRs Activated by Neurotransmitters and Chemokines. Cells, 10(5), 1228. https://doi.org/10.3390/cells10051228

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17 days ago
Foundational Neuroscience EssayCarline Timothee 
RE: Foundational Neuroscience – Response #2
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Hello Ndidi,

Thank you for your informative addition to my post regarding G proteins, GPCRs and ion gated channels to practice for the PMHNP. I’m glad you came across this article in the study of schizophrenia and about the control for brain cognitive functions, they are expected to open new avenues for selective drug development. The integration of neurotoxicological research into the future development of new treatments strategies for schizophrenia holds significant promise by CO G Honer Can J psychiatry 1994 Feb.

Reference
Honer WG. New perspectives on the clinical neurobiology of treatment response in schizophrenia. Can J Psychiatry. 1994 Feb;39(1):34-42. doi: 10.1177/070674379403900108. PMID: 7910778.

Discussion: Foundational Neuroscience

As a psychiatric nurse practitioner, it is essential for you to have a strong background in foundational neuroscience. In order to diagnose and treat patients, you must not only understand the pathophysiology of psychiatric disorders but also how medications for these disorders impact the central nervous system. These concepts of foundational neuroscience can be challenging to understand. Therefore, this Discussion is designed to encourage you to think through these concepts, develop a rationale for your thinking, and deepen your understanding by interacting with your colleagues Foundational Neuroscience Essay.

Foundational Neuroscience Essay

Photo Credit: Getty Images/Cultura RF

For this Discussion, review the Learning Resources and reflect on the concepts of foundational neuroscience as they might apply to your role as the psychiatric mental health nurse practitioner in prescribing medications for patients.

By Day 3 of Week 2

Post a response to each of the following:

  1. Explain the agonist-to-antagonist spectrum of action of psychopharmacologic agents, including how partial and inverse agonist functionality may impact the efficacy of psychopharmacologic treatments.
  2. Compare and contrast the actions of g couple proteins and ion gated channels.
  3. Explain how the role of epigenetics may contribute to pharmacologic action.
  4. Explain how this information may impact the way you prescribe medications to patients. Include a specific example of a situation or case with a patient in which the psychiatric mental health nurse practitioner must be aware of the medication’s action. Foundational Neuroscience Essay

Read a selection of your colleagues’ responses.

By Day 6 of Week 2

Respond to at least two of your colleagues on two different days in one of the following ways:

  • If your colleagues’ posts influenced your understanding of these concepts, be sure to share how and why. Include additional insights you gained.
  • If you think your colleagues might have misunderstood these concepts, offer your alternative perspective and be sure to provide an explanation for them. Include resources to support your perspective.

Note: For this Discussion, you are required to complete your initial post before you will be able to view and respond to your colleagues’ postings. Begin by clicking on the “Post to Discussion Question” link and then select “Create Thread” to complete your initial post. Remember, once you click on Submit, you cannot delete or edit your own posts, and you cannot post anonymously. Please check your post carefully before clicking on Submit!

Foundational Neuroscience Essay sample 2

Explain the agonist-to-antagonist spectrum of action of psychopharmacologic agents, including how partial and inverse agonist functionality may impact the efficacy of psychopharmacologic treatments.  Provide specific examples to agonists, antagonists, partial agonists, and inverse agonists that we use in Psychotherapy

The agonist-to-antagonist spectrum provides the framework for understanding the actions and effects of psychopharmacological medications. Agonists are agents with a high affinity to the target receptors, where they bind to produce a response (Stahl, 2021). Antagonists bind to the receptors to reduce the likelihood of occupancy by antagonists. An example of an agonist is Adderall which increases dopamine release. Seroquel is an antagonist that blocks dopamine receptors. Antagonists may be classified as partial or full based on the level of their efficacies (Stahl, 2021). While full antagonists generate maximal responses, partial agonists such as buprenorphine produce suboptimal responses. Inverse agonists such as Valium may reduce the efficacy of other drugs by selectively binding to unoccupied parts of the receptors (Schatzberg & Nemeroff, 2017).

Compare and contrast the actions of g couple proteins and ion gated channels.

G-couple proteins function by binding to ligands and activating the G-protein, which interacts with enzymes or ion channels in the membrane. These receptors signal cells through a series of actions (Schatzberg & Nemeroff, 2017). In contrast, ion-gated channels bind ligands and induce the opening of channels in the membrane to allow particular ions to cross. The channels are opened as a result of structural changes of proteins (Stahl, 2021).

Explain how the role of epigenetics may contribute to pharmacologic action.

Epigenetics may be useful in drugs’ pharmacological actions in multiple ways. First, epigenetics can be used to increase a drug’s response by altering the genes coding enzymes responsible for the metabolism of these drugs (Grawe, 2017). Foundational Neuroscience Essay Also, epigenetics could be used to increase receptor availability, which would enhance the drugs’ pharmacological effects (Stahl, 2021).

Explain how this information may impact the way you prescribe medications to patients. Include a specific example of a situation or case with a patient in which the psychiatric mental health nurse practitioner must be aware of the medication’s action.

The information about the medications’ actions would be important when dealing with patients with concurrent depression and bipolar disorder. Quetiapine is given for bipolar disorder because of its antagonistic action on serotonin receptors (Stahl, 2021). However, the action of quetiapine would limit the efficacy of fluoxetine, as an agonist for serotonin, for depression treatment (Grawe, 2017) Foundational Neuroscience Essay. The nurse practitioners must ensure the actions of the prescribed medication do not interact for optimal treatment outcomes.

References

Grawe, K. (2017). Neuropsychotherapy: How the neurosciences inform effective psychotherapy. Routledge.

Schatzberg, A. F., & Nemeroff, C. B. (Eds.). (2017). The American psychiatric association publishing textbook of psychopharmacology. American Psychiatric Pub.

Stahl, S. M. (2021). Stahl’s essential psychopharmacology: neuroscientific basis and practical applications. Cambridge University Press.

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19 days ago
Foundational Neuroscience EssaySteven St. Onge WALDEN INSTRUCTOR MANAGER 
RE: Week 2 initial post
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Hi Fidelia,

Great summary here.  Can you share why we would combine a partial agonist such as Buprenorphine with an antagonist such as Naloxone into a single medication such as Suboxone?  As you are probably aware, oral naloxone has nearly 0% bioavailability when given orally.  If none of the drug is absorbed, why use it in the combination?

Thanks!

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19 days ago
Foundational Neuroscience EssayFidelia Chukwuto 
RE: Week 2, instructor’s response
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Hello, Dr. St. Onge,

Partially agonists have both agonistic and antagonistic actions, which is crucial. A partial agonist will function as an antagonist in the presence of a full agonist, competing with the full agonist for the same receptor and decreasing the full agonist’s capacity to exert its maximal impact. An agonist is a compound that attaches to the receptor and generates a reaction like the chemical and receptor that been targeted. The antagonist is the antagonist’s polar opponent. It binds to receptors, preventing them from generating the desired response.

Buprenorphine is a partial opioid agonist, meaning it activates opioid receptors but not to the same extent as many other abused opioids like heroin and prescription painkillers. This means it provides enough opioid effects to relieve withdrawal and cravings without eliciting a robust and rewarding high. Therefore, Naloxone is an opioid overdose reversal medication that has been authorized by the Food and Drug Administration (FDA). It’s an opioid antagonist, which means it attaches to opioid receptors and can counteract and inhibit the effects of opioids like heroin, morphine, and oxycodone (NIDA. 2022)

Reference

NIDA. 2022, January 11. Naloxone DrugFacts. Retrieved from https://nida.nih.gov/publications/drugfacts/naloxone on 2022, March 11

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19 days ago
Foundational Neuroscience EssayAntonio Ingram 
RE: Week 2, instructor’s response
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There are three different opioid receptors they are Mu, Kappa, and delta. The receptor that is most relevant in opioid abuse is the MU receptor (Arcangelo et al., 2017). The MU receptor is where the opioids exert most of their desired effects like euphoria, analgesia, and addictive effects. Opioids can interact with receptors in different ways by an agonist, antagonist, and partial agonist(Arcangelo et al., 2017).

Agonists activate receptors in the brain. Agonists bind to the target receptors and turn them on. Full MU agonist activates mu receptors. Opioids with the greatest abuse potential are the full agonist, for example, methadone, and oxycodone (Stahl, 2013). Partial agonist possesses some properties of both antagonist and full agonist. Partial agonists bind to receptor sites and activate them but, not to the effect of a full agonist.  In partial agonist medications like buprenorphine, they don’t produce an increasing effect over a certain level.

Stahl, S. M. (2013). Stahl’s Essential Psychopharmacology: Neuroscientific Basis and Practical Applications (4 edition). Cambridge University Press.

Arcangelo, V. P., Peterson, A. M., Wilbur, V., & Reinhold, J. A. (Eds.). (2017). Pharmacotherapeutics for advanced practice: A practical approach (Fourth edition). Wolters Kluwer.

Foundational Neuroscience Essay sample 3

Explain the agonist-to-antagonist spectrum of action of psychopharmacologic agents, including how partial and inverse agonist functionality may impact the efficacy of psychopharmacologic treatments.

The agonist is the molecule that increases the action of the neurotransmitter(s) that it responds to. It copies the effect(s) of a neurotransmitter and binds and stimulates the receptor site to produce a response. On the other hand, the antagonist does the opposite of the agonist, where it opposes the outcome of the agonist by blocking the action of the neurotransmitter causing it to interfere or decrease the neurotransmitter that it corresponds to. According to (Online Nursing Classes, 2021, p. 1), “Foundational Neuroscience Essay The spectrum of agonist to antagonist consists of a full agonist, partial agonist, silent antagonist, inverse agonist, and irreversible agonist. A full agonist allows the receptor to fully open the ion channel, which allows maximum signal transduction to occur; a partial agonist partially enhances signal transduction; the silent antagonist will return the receptor to a resting state; the inverse agonists go beyond antagonism and even blocks constitutive activity; and the irreversible agonist binds and activates the receptor, but the binding is permanent, and the receptor is essentially destroyed (AegisShield, 2015)”. An example of a full agonist is morphine, which gives the receptors full capacity of the medication to go inside and use these pathways to the maximum level. A partial agonist is like the medication buprenorphine, which partially opens the channels, not to the fullest or maximum levels, just enough to create a pathway for these ions to go through. An antagonist is like naloxone which does not open any channels, however, it will block the pathways from anything going in or out of these channels. It is like giving morphine and if the patient has respiratory depression or overdoses, the naloxone can be given to block the pathways and stop it from receiving the full maximum capacity of the morphine, being an agonist.

Compare and contrast the actions of g couple proteins and ion gated channels.

G coupled proteins are also called GPCR’s meaning G protein-coupled receptors. These proteins are known for, according to(Online Nursing Classes, 2021), its high diversity in recognizing wide range of ligands, including photons, small molecules and proteins. According to (Daniel & Clark, 2017, p. 1), states that “G-protein coupled receptors (GPCRs) are ubiquitously expressed on the surface of cells and act to transduce extracellular signals and regulate physiological processes”. Meaning they transmit signals across the cell membrane with recognizable extracellular substances that are responsible for the signals of conversion inside the cell(s).

(Online Nursing Classes, 2021), explains simply that ion gated channels are also called ligands, which are pores in the cellular membrane that allows ions to pass in and out of the cell; it attaches to the g protein(s). In nerve cells they are ion transporters responsible for maintaining the pathways across the cell. Both the g coupled proteins work together with the ion gated channels which can be either hormones, neurotransmitters, or drugs to go across the gated pathways in and out of the cells. Ion gated channels attach to the g proteins and causes the cells to open up to these hormones, neurotransmitters, or drugs and helps it cycle throughout the body and triggered areas, depending on what the ligand is.

Explain how the role of epigenetics may contribute to pharmacologic action.

Epigenetics is defined as the study of how the environment and behaviour can cause transitions that impact the functions of one’s genes. In genetics, the DNA sequence can be altered, however, in epigenetics, it is where pharmacology, drug metabolism, or the environment, especially pharmacokinetics can play a huge role on these mechanisms. According to(Stefanska & MacEwan, 2015), “These epigenetic mechanisms are systems that have evolved to either switch off gene activity altogether, or fine-tune any existing genetic activation. Such systems are present in all genes and include chromatin modifications and remodeling, DNA methylation (such as CpG island methylation rates) and histone covalent modifications (e.g. acetylation, methylation), RNA interference by short interfering RNAs (siRNAs) and long non-coding RNAs (ncRNAs)”. In other words, normal phenotypic (the interaction of genes and the environment) activity of cells plays a huge role in epigenetics. It changes the phenotype but not the genotype of the DNA sequence.

Explain how this information may impact the way you prescribe medications to patients. Include a specific example of a situation or case with a patient in which the psychiatric mental health nurse practitioner must be aware of the medication’s action Foundational Neuroscience Essay.

It is said that epigenetic alterations are fundamental in both disease and normal state of a patient. According to (YouTube.com [Pharmacogenomics: Genes and Medicine], 2020), it depends on how a person metabolizes a medication and how it affects them. There are many types of metabolisms for all humankind: poor, intermediate, rapid (normal), or ultrarapid. An example would be the medication codeine and breastfeeding women. If a normal person takes tylenol #3 (which has codeine in it), they are able to receive the ultimate response, which is to alleviate pain. However, if we put a breastfeeding mother into the picture, although it alleviates their pain, the codeine which will turn into morphine in the blood, will depend on what type of metabolism this mother has. If they have poor metabolism, the baby will not or will barely have morphine in their system. But, if the mother is ultrarapid, the baby will have increase levels of morphine in their blood and system, causing the baby to have slow respirations and may cause them death in the end. Therefore, as a prescriber of medications, all nurse practitioners should have to learn the concepts and the knowledge of specific medications, its adverse effects, its side effects, how its effects on the geriatric, pregnant women, breast-feeding women, and so forth. There are many mechanisms of these drugs that will cause overdose or fatal effects, so, as prescribers one day, we all should learn the best we know how and prescribe with caution.

References

Daniel, J., & Clark, R. (2017). G-protein coupled receptors targeted by analgesic venom peptides. Toxins, 9(11), 372. https://doi.org/10.3390/toxins9110372

Molecular Devices. (2021, January 25). Gpcrs (g protein-coupled receptors). Retrieved March 6, 2022, from https://www.moleculardevices.com/applications/g-protein-coupled-receptors#gref

Online Nursing Classes. (2021, June 11). The agonist-to-antagonist spectrum of action of psychopharmacologic agents – online nursing classes. https://onlinenursingclasses.org/the-agonist-to-antagonist-spectrum-of-action-of-psychopharmacologic-agents/#:~:text=Antagonists%20are%20known%20as%20the%20mediators%20of%20therapeutic,agonist%2C%20silent%20antagonist%2C%20inverse%20agonist%2C%20and%20irreversible%20agonist.

Stefanska, B., & MacEwan, D. J. (2015). Epigenetics and pharmacology. British Journal of Pharmacology, 172(11), 2701–2704. https://doi.org/10.1111/bph.13136

YouTube.com. (2020, April 10). Pharmacogenomics: Genes and Medicine [Video]. YouTube. https://www.youtube.com/watch?v=RXmrUhSSSlo

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19 days ago
Foundational Neuroscience EssaySteven St. Onge WALDEN INSTRUCTOR MANAGER
RE: Week 2-Discussion
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Hi Kristine,

Great summary here.  Can you share why we would combine a partial agonist such as Buprenorphine with an antagonist such as Naloxone into a single medication such as Suboxone?  As you are probably aware, oral naloxone has nearly 0% bioavailability when given orally.  If none of the drug is absorbed, why use it in the combination?

Thanks!

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17 days ago
Foundational Neuroscience EssayKristine Umiten 
RE: Week 2-Discussion
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​

Hello Professor Onge,

Thank you for your comments and questions. To answer your questions on the discussion, a combination of buprenorphine/naloxone is mainly used with patients in a withdrawal situation. They may have symptoms of seizures or sweats, etcetera, to help ease the process of withdrawals from using prescription drugs or recreational drugs. If you stop using these drugs cold turkey, especially if the patient has been taking these drugs for years, the effects of the body may be detrimental to the patient’s health. So if you introduce a small amount of the buprenorphine with the naloxone, it helps facilitate these symptoms. It is like titrating certain drugs like prednisone, the same concept. According to (Antoine et al., 2020, p. 1), “a buprenorphine/naloxone induction protocol that was outlined in an early publication has now become a fairly routine process whereby individuals receive a 4 mg sublingual (SL) dose of buprenorphine/naloxone once they demonstrate mild opioid withdrawal, are monitored for precipitated withdrawal, and receive a second 4 mg SL dose approximately 3 hours later”.

The best way to treat drug overdose is stated in (Razaghizad et al., 2021), there is “evidence suggesting that OEND (Overdose education and naloxone distribution) programs produce long-term knowledge improvements, improve participants’ attitudes toward naloxone, provide sufficient training for participants to manage overdoses safely and effectively, and effectively reduce opioid-related mortality”. Naloxone is used for drug adverse effects such as respiratory depression causing slow respirations leading to death. Naloxone is the drug antidote for overdose in opioids and/or recreational drugs. With this, naloxone will chemically help block the receptors in the cells to not attach, therefore, the drugs used (that causes withdrawals) cannot go inside the cells and be absorbed by the body. Foundational Neuroscience Essay.

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References

Antoine, D., Huhn, A. S., Strain, E. C., Turner, G., Jardot, J., Hammond, A. S., & Dunn, K. E. (2020). Method for successfully inducting individuals who use illicit fentanyl onto buprenorphine/naloxone. The American Journal on Addictions, 30(1), 83–87. https://doi.org/10.1111/ajad.13069

Razaghizad, A., Windle, S. B., Filion, K. B., Gore,G., Kudrina, I., Paraskevopoulos, E., Kimmelman, J., Martel, M. O., & Eisenberg, M. J. (2021). The effect of overdose education and naloxone distribution: An umbrella review of systematic reviews. American Journal of Public Health, 111(8), e1–e12. https://doi.org/10.2105/ajph.2021.306306

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17 days ago
Foundational Neuroscience EssayNICHOLE HOLLAND 
RE: Week 2-Discussion
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Hello Kristine,

I think you did a great job on your post this week. Your summary of epigenetics and how they contribute to pharmacologic action. According to Ganesan,

Arimondo, Rots, Jeronimo & Berdasco (2019) epigenetics is an important part of an organism’s development and its response to environmental cues.  The validation of epigenetic biomarkers will help with diagnosis and predicting drug response.  There are various challenges and opportunities for the use of

epigenetic drugs in clinical use, including target selection and clinical considerations and chemistry-associated concerns. The progress in epigenetic drug

discovery and the growing interests of epigenetic mutations in diseases and biomarkers will help improve treatment of patients with mood disorders

Ganesan, Arimondo, Rots, Jeronimo & Berdasco, 2019)

An article by Lockwood and Youssef (2017) discussed epigenetic changes associated with the use of mood stabilizers or antipsychotic medications.

Their findings suggest that many bipolar medications are linked to epigenetic changes.  They also believe that the stages of bipolar disorder could

possibly be identified in patients, allowing for more specialized treatment, to improve patient care. Lockwood and Youssef (2017) suggest it may be

easier to implement patient centered approaches to pharmacotherapy by combining the knowledge of epigenetic effects of bipolar illness with epigenetic

effects of mood stabilizers and antipsychotics (Lockwood & Youssef, 2017). Foundational Neuroscience Essay

References

Ganesan, A., Arimondo, P. B., Rots, M. G., Jeronimo, C., & Berdasco, M. (2019). The timeline of epigenetic drug discovery: From reality to

dreams. Clinical Epigenetics, 11, 1-17. doi:http://dx.doi.org/10.1186/s13148-019-0776-0

Lockwood LE, Youssef NA. Systematic Review of Epigenetic Effects of Pharmacological Agents for Bipolar Disorders. Brain Sci. 2017 Nov

18;7(11):154. doi: 10.3390/brainsci7110154. PMID: 29156546; PMCID: PMC5704161.

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17 days ago
Foundational Neuroscience EssayKristine Umiten 
RE: Week 2-Discussion
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​

Hello Nicole,

Thank you for your comments on my discussion paper this week. Bipolar disorder is definitely a mental illness that needs further studies. However, the mechanisms for treatments are similar. It was said in (Peedicayil, 2014), that “most work on epigenetic therapy is focussed on the design and development of drugs targeting DNA methylation and drugs inhibiting the enzyme histone deacetylase”. In bipolar disorder antipsychotic medications are given to control the mania.

(Scaini et al., 2020, p. 2) states that there are no alterations in the DNA-sequence of the patient just the functions of the brain. How epigenetics works is by gene-by-environment interactions and modulate gene expression. In other words, it doesn’t change the genes of the patient, it can still be brought down from family members through generations to come. In bipolar disorders, anti-psychotics medications are used to help imbalances of the brain’s neurotransmitters and help balance out symptoms that the patient is encountering.

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References

Peedicayil, J. (2014). Epigenetics and the war on mental illness. Molecular Psychiatry, 19(9), 960–960. https://doi.org/10.1038/mp.2014.16

Scaini, G., Valvassori, S. S., Diaz, A. P., Lima, C. N., Benevenuto, D., Fries, G. R., & Quevedo, J. (2020). Neurobiology of bipolar disorders: A review of genetic components, signaling pathways, biochemical changes, and neuroimaging findings. Brazilian Journal of Psychiatry, 42(5), 536–551. https://doi.org/10.1590/1516-4446-2019-0732 Foundational Neuroscience Essay

INITIAL POST – FOUNDATIONAL NEUROSCIENCE
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Foundational Neuroscience Essay sample 4

Agonist-to-Antagonist spectrum of action of psychopharmacologic agents

 The purpose of using a psychopharmacologic agent is to achieve an agonist, antagonist, or partial agonist effect Foundational Neuroscience Essay.  An agonist is an agent that binds to a receptor and activates the receptor. This activation enables the drug or agent to effect a conformational change in the receptor to achieve a desired effect on the system. An antagonist, on the other hand, when bound to the receptor prevents its activation.  The agonist-antagonist spectrum of action is well illustrated by the quantitative literature review on smoking cessation by Rollema & Hurst (2018). In this review, the authors demonstrated that the activation of some agonist receptors achieved the same effect as inhaling nicotine. The report also demonstrated that the antagonistic effect of another agent was also effectively used, during a smoking cessation relapse, to, competitively, block nicotine receptors. This explains the use of the dual agonist-antagonist action of Chantix (Varenicline) for smoking cessation.

A partial agonist, as the name suggests, partially activates a receptor. An inverse agonist, on the other hand, reverses the action of the ligand (agonist). Foundational Neuroscience Essay In this latter case, the receptor is already intrinsically activated, and the agency of an inverse agonist is used to stop the process. An example is seen in the intrinsic activity of the benzodiazepine receptor which keeps the system calm. An agonist will increase the level of sedation while an inverse agonist will stop the intrinsic activity of the receptor (Nutt et al., 2017).  An example of partial agonist action in psychopharmacology is seen in the use of Buprenorphine (Naloxone) in opioid addiction treatment (Withey et al., 2019). Naloxone has an attenuated action profile compared to the full agonist action of opioids and provides some of the “benefits” of opioids over a longer period, thus reducing dependence on opioids.

G Couple Proteins and Ion-Gated Channels

G couple proteins are transmembrane proteins composed of seven segments with seven receptors for binding with GTP or GPD, guanine nucleotides, or proteins. When a pharmaceutical agent binds on a receptor and effects an intracellular change, they may need another agent to convey their actions to the target cells. The g protein is one such agent. In other words, it relays the message received by the receptor and transports it down to enable the cascade of enzymatic actions resulting in the directed cellular conformations to bring about a desired cellular response.

Ion gated channels are transmembrane-bound receptors that are activated by the binding of a ligand or a chemical messenger, say a drug. They typically abound on excitable cells like neurons. The ion gated channels open when a ligand binds allosterically to the specific receptor(s) allowing ions like potassium, sodium, calcium, and chloride to enter cells. Foundational Neuroscience Essay The movement of ions across the cell membranes creates the action potential. Weir (2020) notes that the actions of these channels can be modulated by medications like anxiolytics.

It is important to note that the g protein is a receptor (Weir, 2020) that binds intracellularly to the membrane receptor to effect changes within the cell while the ion gated channel is activated extracellularly (usually) to allow the cross-flow of ions in and out of the cell.

Epigenetics and Pharmacology

 The impact of the environment on how the genetic makeup is expressed is described as epigenetics. This can occur through histone modification or DNA methylation. With histone modification, genes (proteins) are not fully expressed while DNA methylation occurs when an additional methyl group is attached to a section of the DNA. Both processes can result in pathological mutations. Understanding the role of epigenetics means an appreciation of inherent risk factors which should guide diagnosis and care protocols for our patients. Studies have shown that the use of Metformin in diabetes decreases DNA methylation which if allowed to continue unchecked increases the risk of hyperglycemia and obesity in type 2 diabetics (García-Calzón et al., 2017). The recent pharmacological review by Kringel et al. Foundational Neuroscience Essay (2021) is even more promising as it underscores the efficacy of marrying epigenetics onto pharmacology to modulate the processes of histone modulation and DNA methylation. This, according to the report, has influenced the development of drugs based on the epigenetics of patients. Interestingly, the study also noted that some drugs that were non-epigenetic were later found to have some positive implications for epigenetics. Examples included Valproate, Escitalopram, and Fluoxetine widely used for the treatment of bipolar disorder and major depression amongst others.

Impact on Practice

An understanding of the mechanism of the action of medications is important to enhance practice and protect the patient. Knowing what medication potentiates or attenuates a certain action or activity will help a practitioner to correlate symptoms to pharmaceuticals. Foundational Neuroscience Essay For the PMHNP, this is particularly important. Of recent, there has been much discourse on why Lithium is not being used widely for the treatment of Bipolar Disorder when evidence shows that it reduces suicidal ideation and suicides in this population (Fountoulakis et al., 2022). It takes an understanding of the mechanism of action and understanding what receptors are involved (excited or inhibited) and what ion gates are involved – all requiring close management of the dosage and serum drug levels in the blood. Foundational Neuroscience Essay

References

Fountoulakis, K. N., Tohen, M., & Zarate, C. A. (2022). Lithium treatment of Bipolar disorder in adults: A systematic review of randomized trials and meta-analyses. European Neuropsychopharmacology: The Journal of the European College of Neuropsychopharmacology, 54, 100–115. https://doi.org/10.1016/j.euroneuro.2021.10.003

‌ García-Calzón, S., Perfilyev, A., Männistö, V., de Mello, V. D., Nilsson, E., Pihlajamäki, J., & Ling, C. (2017). Diabetes medication associates with DNA methylation of metformin transporter genes in the human liver. Clinical Epigenetics, 9(1). https://doi.org/10.1186/s13148-017-0400-0

Kringel, D., Malkusch, S., & Lötsch, J. (2021). Drugs and Epigenetic Molecular Functions. A Pharmacological Data Scientometric Analysis. International Journal of Molecular Sciences, 22(14), 7250 Foundational Neuroscience Essay. https://doi.org/10.3390/ijms22147250

‌Nutt, D., Stahl, S., Blier, P., Drago, F., Zohar, J., & Wilson, S. (2017). Inverse agonists – What do they mean for psychiatry? European Neuropsychopharmacology, 27(1), 87–90. https://doi.org/10.1016/j.euroneuro.2016.11.013

‌Rollema, H., & Hurst, R. S. (2018). The contribution of agonist and antagonist activities of α4β2* nAChR ligands to smoking cessation efficacy: a quantitative analysis of literature data. Psychopharmacology, 235(9), 2479–2505. https://doi.org/10.1007/s00213-018-4921-9

Weir, C. J. (2020). Ion channels, receptors, agonists and antagonists. Anaesthesia & Intensive Care Medicine, 21(1), 62–68. https://doi.org/10.1016/j.mpaic.2019.10.022

Withey, S. L., Spealman, R. D., Bergman, J., & Paronis, C. A. (2019). Behavioral Effects of Opioid Full and Partial Agonists During Chronic Buprenorphine Treatment. The Journal of Pharmacology and Experimental Therapeutics, 371(2), 544–554. https://doi.org/10.1124/jpet.119.259010

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20 days ago
Foundational Neuroscience EssayLindsay Allen 
RE: INITIAL POST – FOUNDATIONAL NEUROSCIENCE
COLLAPSE

Ndidi-Amaka,

I thoroughly enjoyed your research and explanation of applicable examples. Your information on buprenorphine increased my interest, as this is a medication, I have administered to patients frequently in my nursing career. Buprenorphine is a high affinity, partial agonist that acts on the mu opioid receptor, as you stated in your original post (Coe et al., 2019) Foundational Neuroscience Essay. Buprenorphine subdues opioid withdrawal and cravings, decreases illegitimate opioid abuse, and prohibits the exogenous effects of opioids on the respiratory system, specifically, respiratory depression (Coe et al., 2019). Buprenorphine was approved for use in the United States in 2002 by the Food and Drug Administration for opioid use disorder (Coe et al., 2019). Buprenorphine is also being investigated for use in depression treatment because it also acts on the kappa opioid receptors that are involved in the stress response (Coe et al., 2019).

It is highly important to incorporate the use of epigenetics when prescribing and treating patients. The environment and individual lifestyle factors of individuals should be treated as such, as no medication produces the same effect in all patients (Miller, 2021). It is known that epigenetic modifications do not alter the DNA sequence but modify the accessibility of the DNA and the chromatin structure, which in turn lead to differences in gene expression. Smoking, pollution, alcohol, obesity, sedentary lifestyle, poor diet, and stress can all influence these modifications (Miller, 2021) Foundational Neuroscience Essay.

References

Coe, M.A., Lofwall, M.R., & Walsh, S.L. (2019). Buprenorphine pharmacology review: Update on transmucosal and long-acting formulations. Journal of Addiction Medicine, 13(2), 93-103. doi: 10.1097/ADM.0000000000000457

Miller, J.J. (2021) Epigenetics collide with pharmacogenomics. PsychiatricTimes, 38(10). Retrieved from https://www.psychiatrictimes.com/view/epigenetics-collide-pharmacogenomics Foundational Neuroscience Essay

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19 days ago
Foundational Neuroscience EssayNdidi-Amaka Onyema 
RE: INITIAL POST – FOUNDATIONAL NEUROSCIENCE
COLLAPSE

Thanks for the additional insight. It now makes sense why patients still “crave”for these partial agonists.

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19 days ago
Foundational Neuroscience EssayMyrtle Johnson 
Peer Response 1
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Ndidi-Amaka Onyema,

“Lithium treatment remains the “gold standard” of treatment for preventing recurrences in bipolar disorder, both types I (with mania and major depression) and II (with depression and hypomania)” (Tondo et al., 2019). According to Rybakowski (2019), lithium has multiple assets other than antimanic prophylactic effects, it also has antidepressant action, suicide prevention, pro-cognitive and anti-dementia effects. PMHNP must know that routine blood tests must be performed to prevent toxicity. They also must know the adverse reactions when taken with other medications such as NSAIDs, ace inhibitors, and diuretics since they can cause an increased serum level of lithium. Foundational Neuroscience Essay “Abnormally high blood levels of lithium (above 1.5 mEq/L) can increase risk of intoxication, signs of which are severe tremor, confusion, vomiting, abdominal pain, diarrhea, abnormally increased reflexes, speech difficulties, abnormal heart rhythm, hypotension, and convulsions” (Tondo et al., 2019) Foundational Neuroscience Essay.

References

Rybakowski, J. K. (2019). Guides for users and prescribers of Lithium. International Journal of Bipolar Disorders, 7(1). https://doi.org/10.1186/s40345-019-0166-8

Tondo, L., Alda, M., Bauer, M., Bergink, V., Grof, P., Hajek, T., Lewitka, U., Licht, R. W., Manchia, M., Müller-Oerlinghausen, B., Nielsen, R. E., Selo, M., Simhandl, C., & Baldessarini, R. J. (2019). Clinical use of lithium salts: Guide for users and Prescribers. International Journal of Bipolar Disorders, 7(1). https://doi.org/10.1186/s40345-019-0151-2 Foundational Neuroscience Essay