Contact: to feature here

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Is GLYX- 13 A Possible Antidepressant Without Side Effects?
GLYX- 13 is ketamine molecular cousin. This tetrapeptide is a NMDA receptor partial agonist. It's neuroprotective effects delay death of CA- 3, CA- 1 under hypoxia and hypoglycemia conditions.

This tetrapeptide has similar influence on human brain like ketamin. However, ketamine is used in many cases such as analgesia, anesthesia, elevated blood pressure and other indications. GLYX- 13 has antidepressant effects without side effects.

Ketamine has shown effectiveness in depression treatment in patients with bipolar disorder. Persons with major depressive disorder have shown good response when they took ketamine drug.

Limitations of major depressive disorder drugs

Ten percent of population is affected with major depression syndrome. According to World health organisation, this disorder is second syndrome that leads to disability in modern world. This fact was involved in creation of big number and several classes of antidepressant drugs. However, not everyone is responsive to these drugs. Several researches revealed that up to 40% of population is unresponsive to any kind of treatment. Moreover, selective serotonin reuptake inhibitors take weeks to be effective, thus suicide is not so rare in this period of few weeks.

Function of NMDA receptors

NMDA receptors were linked to memory and learning by scientist for thirty years ago. Soon after that, pharmaceutical companies tried to block these receptors in order to prevent stroke. However, this experiment led to an unordinary consequence- expansion of cardiovascular disease. These experiments and researches were slowed down, but ketamine, already widely used medication for anesthesia began revolution in depression treatments.

Ketamine properties and disadvantages

Ketamine presented a real revolution in depression treatment. It needs only two hours to take effect, while SSRI needs two weeks. That is significant result in depression treatment. But, not every single thing about ketamine is positive. It has vast of side effects like hallucinations, excessive sleeping disorder and substance abuse behavior.

GLYX- 13 is very different from ketamine. There is a crucial difference between these two drugs, and it is blocking of ion channel. GLYX- 13 does not block this ion channel, and this is maybe the answer why this drug has not same side effects.

Previous studies have shown that GLYX- 13 improved memory and learning in rats. Also, GLYX- 13 showed analgesic effects. These properties are not common for GLYX- 13 and ketamine, they are only properties of GLYX- 13.

Accidental development of GLYX- 13

Researchers developed GLYX- 13 accidentally. One of researchers created, monoclonal antibodies, specific molecules in order to use them in various experiments. These experiments were planned for understanding the pathways of memory and learning. Of course, some of these antibodies were created for NMDA researches. After a certain number of unsuccessful experiments, they began conversion of these antibodies to small protein molecules. One of these molecules is GLYX- 13 molecule, created of only four amino acids.

Experiments with GLYX- 13, ketamine and fluoxetine

Researches and results of researches on four compounds: GLYX- 13, inactive form of GLYX- 13, ketamine and fluoxetine (SSRI drug). Ketamine and GLYX- 13 gave rapid effects within one hour. Also, antidepressant-like effects lasted 24 hours. SSRI typical drug, fluoxetine, did not produce rapid effect on patients. It took two to four weeks for effects expression. Last one, scrambled GLYX- 13, showed no antidepressant-like results.

An increase of NMDA receptor NR2B and chemical messenger glutamate receptor called AMPA in hippocampus was presented in protein studies. Moreover, electrophysiology studies pointed that ketamine and GLYX- 13 supported long lasting transmission of signals in hippocampus. This promotion of signals is also called long term potentiation or simply- synaptic plasticity. This process is very important in memory and learning process.

There are some theories how GLYX- 13 works. One of the theories proposes theory of NR2B receptor activation by GLYX- 13. After this activation, few events like intracellular calcium influx and the expression of AMPA occur. These events are responsible for increased communication between neural cells.

Evaluation of results

Results from these researches are similar to results from phase two from a recent clinical study. This results showed that only one administration of GLYX- 13 gave significant reduction of depression in patients with major depressive disorder. This is maybe greater achievement, because these patients had failed treatment with conventional drugs.

Administration of a single dose of GLYX- 13 gave significant results in 24 hours, and they lasted nearly a week. Application of GLYX- 13 is well tolerated. One of big advances in this therapy is lack of schizophrenia- like symptoms, which may occur in treatments with conventional NMDA receptor modulating agents.

A molecule each of amino acid chemical messengers glutamate and glycine is needed for NMDA receptors to become activated. There are speculations that GLYX- 13 directly binds to the NMDA receptors glycine`s site. Other speculations say that GLYX- 13 modulates how glycine and receptor works together indirectly. By these assumptions, antidepressant effects are caused by previously mentioned activation of NMDA and AMPA receptors, involved in learning and memory. On the other hand, ketamine has different way of functioning. It only blocks NMDA receptors, but increases activation of AMPA receptors. This results could help us in understanding of major depression disorder and development of new generation of antidepressant drugs.

Future of GLYX- 13 research

Nowadays, GLYX- 13 is being tested in clinical trials phase two where scientist have plan to find out which dose of this modern antidepressant drug is needed for humans. Another questions are waiting to be answered: does GLYX- 13 have power to regulate twenty receptor subtypes and is this GLYX- 13 protein able to give positive effects in other disorders like: schizophrenia, autism and attention- deficit hyperactivity disorder? These question could be answered soon, because research started in 1983 could give important answers to scientists.
Like Post Reply
Hello-What about using conventional MNDA receptor agonists? Like Namenda? While we are waiting for GLYX-13? Waiting and suffering?

Like Post Reply
(07-04-2013, 10:43 AM)blueheelercd Wrote: Hello-What about using conventional MNDA receptor agonists? Like Namenda? While we are waiting for GLYX-13? Waiting and suffering?


Hi! Namenda is generally widely used for the treatment of Alzheimer's disease, but there is certain evidence that it can improve symptoms in patients with depressive disorders, especially in those who do not respond well to standard treatment. However, doctors seem to avoid using it because there are not yet enough studies showing its effectiveness.

Like Post Reply

Possibly Related Threads…
Last Post

Users browsing this thread:
1 Guest(s)

Is GLYX- 13 A Possible Antidepressant Without Side Effects?00