c-Fos

Oxytocin, a naturally occurring chemical in the brain, plays a crucial role in various cognitive functions, including memory. A recent study revealed that the activation of neurons in the supramammillary nucleus of the mouse brain enhances performance in object recognition tasks. This discovery implies that specific oxytocin neurons play a pivotal role in modulating object recognition memory in mice. Oxytocin (OXT) is a hormone that is known for its effects on psychological well-being and emotional bonding in animals. Interestingly, research has shown that this natural chemical in the brain plays a crucial role in other cognitive processes as well, including learning and memory. Now, scientists may have discovered exactly how OXT influences memory in animals by studying "OXT neurons" that contain OXT receptors and function differently based on the availability of the chemical in the brain. In a recent study published on 16 November 2023, in PLOS One, a group of researchers, headed by Professor Akiyoshi Saitoh, along with Junpei Takahashi from the Tokyo University of Science, delved into the complex neural pathways and signaling mechanisms activated by OXT. They offered unprecedented insights into its implications for learning and memory. "Previously we had suggested that oxytocin may be a new therapeutic candidate for dementia based on studies using a mouse model of Alzheimer's disease. To investigate this further, in this study, we examined the role of endogenous OXT in mouse cognitive function. This was done by using pharmacogenetic techniques to specifically activate OXT neurons in specific brain regions. The cognitive function of mice was then evaluated using the Novel Object Recognition Task (NORT)," explains Prof. Saitoh. The research emphasizes the significant role of OXT in regulating social memory, as deficiency in either OXT or its receptors has been linked to aberrant social memory in mice. This groundbreaking study, however, shifts the focus to the role of endogenous OXTergic projections in learning and memory, particularly within the supramammillary nucleus (SuM). To identify the neurons that are responsible for OXT's effect on memory, the researchers visualized slices of the mouse brain after specifically activating OXT neurons in the paraventricular hypothalamic nucleus (PVN), observing positive signals in the PVN and its projections to the SuM. Additional validation of OXTergic neuron activation was confirmed through increased c-Fos positive cells (indicating neuron activation) in the PVN after administering clozapine N-oxide (used to activate the neurons). Further, the study focused on the impact of OXTergic neuron activation on learning and memory using the Y-maze and NORT. Surprisingly, no changes were observed in short-term spatial memory in the Y-maze test. However, the activation of OXTergic neurons significantly boosted long-term object recognition memory in the NORT. Intriguingly, an increased number of c-Fos positive neurons in SuM and the dentate gyrus (a region within the brain's hippocampus) after NORT indicated the involvement of OXTergic neurons in maintaining long-term memory through these regions. Additionally, the team employed selective activation of OXTergic axons in SuM, resulting in mice spending more time exploring novel objects, suggesting a direct modulation of object recognition memory by OXTergic axons projecting from PVN to SuM. This study, for the first time, reveals the involvement of OXT in object recognition memory through the SuM. It suggests potential implications for understanding the role of physiological OXT in Alzheimer's disease and highlights the involvement of OXTergic projections in modulating recognition memory. "There is a widely acknowledged belief that dementia tends to advance more rapidly in settings where individuals experience loneliness or limited social engagement. However, the scientific underpinnings of this phenomenon have remained largely elusive. Our research seeks to elucidate the crucial role of a stimulating environment that activates oxytocin in the brain, potentially mitigating the progression of dementia," explains Prof. Saitoh. The ongoing exploration of this field is anticipated to pave the way for innovative treatments and pharmaceutical interventions aimed at halting the advancement of dementia.

Short-lived proteins control gene expression in cells to carry out a number of vital tasks, from helping the brain form connections to helping the body mount an immune defense. These proteins are made in the nucleus and are quickly destroyed once they've done their job. The mechanism degrades short-lived proteins that support brain and immune functions. Short-lived proteins control gene expression in cells to carry out a number of vital tasks, from helping the brain form connections to helping the body mount an immune defense. These proteins are made in the nucleus and are quickly destroyed once they've done their job. Despite their importance, the process by which these proteins get broken down and removed from cells once they are no longer needed has eluded scientists for decades -- until now. In a cross-departmental collaboration, researchers from Harvard Medical School identified a protein called midnolin that plays a key role in degrading many short-lived nuclear proteins. The study shows that midnolin does so by directly grabbing the proteins and pulling them into the cellular waste-disposal system, called the proteasome, where they are destroyed. The findings are published Aug. 24 in Science. "These particular short-lived proteins have been known for over 40 years, but no one had established how they are actually degraded," said co-lead author Xin Gu, a research fellow in neurobiology at HMS. Because the proteins broken down by this process modulate genes with important functions related to the brain, the immune system, and development, scientists may eventually be able to target the process as a way of controlling protein levels to alter these functions and correct any dysfunction. "The mechanism we found is very simple and quite elegant," added co-lead author Christopher Nardone, a PhD candidate in genetics at HMS. "It is a basic science discovery, but there are many implications for the future." A molecular mystery It is well established that cells can break down proteins by tagging them with a small molecule called ubiquitin. The tag tells the proteasome that the proteins are no longer needed, and it destroys them. Much of the pioneering research on this process was done by the late Fred Goldberg at HMS. However, sometimes the proteasome breaks down proteins without the help of ubiquitin tags, leading researchers to suspect that there was another, ubiquitin-independent mechanism of protein degradation. "There has been sporadic evidence in the literature that somehow the proteasome can directly degrade unmarked proteins, but no one understood how that can happen," Nardone said. One group of proteins that seemed to be degraded by an alternative mechanism are stimuli-induced transcription factors: Proteins rapidly made in response to cellular stimuli that travel to the nucleus of a cell to turn on genes, after which they are rapidly destroyed. "What struck me in the beginning is that these proteins are extremely unstable and they have a very short half-life -- once they are produced, they carry out their function, and they are quickly degraded afterwards," Gu said. These transcription factors support a range of important biological processes in the body, yet even after decades of research, "the mechanism of their turnover was largely unknown," said Michael Greenberg, the Nathan Marsh Pusey Professor of Neurobiology in the Blavatnik Institute at HMS and a co-senior author on the paper with Stephen Elledge, the Gregor Mendel Professor of Genetics and of Medicine at HMS and Brigham and Women's Hospital. From a handful to hundreds To investigate this mechanism, the team began with two familiar transcription factors: Fos, studied extensively by the Greenberg lab for its role in learning and memory, and EGR1, which is involved in cell division and survival. Using sophisticated protein and genetic analyses developed in the Elledge lab, the researchers homed in on midnolin as a protein that helps break down both transcription factors. Follow-up experiments revealed that in addition to Fos and EGR1, midnolin may also be involved in breaking down hundreds of other transcription factors in the nucleus. Gu and Nardone recall being shocked and skeptical about their results. To confirm their findings, they decided they needed to figure out exactly how midnolin targets and degrades so many different proteins. "Once we identified all these proteins, there were many puzzling questions about how the midnolin mechanism actually works," Nardone said. With the aid of a machine learning tool called AlphaFold that predicts protein structures, plus results from a series of lab experiments, the team was able to flesh out the details of the mechanism. They established that midnolin has a "Catch domain" -- a region of the protein that grabs other proteins and feeds them directly into the proteasome, where they are broken down. This Catch domain is composed of two separate regions linked by amino acids (think mittens on a string) that grab a relatively unstructured region of a protein, thus allowing midnolin to capture many different types of proteins. Of note are proteins like Fos that are responsible for turning on genes that prompt neurons in the brain to wire and rewire themselves in response to stimuli. Other proteins like IRF4 activate genes that support the immune system by ensuring that cells can make functional B and T cells. "The most exciting aspect of this study is that we now understand a new general, ubiquitination-independent mechanism that degrades proteins," Elledge said. Tantalizing translational potential In the short term, the researchers want to delve deeper into the mechanism they discovered. They are planning structural studies to better understand the fine-scale details of how midnolin captures and degrades proteins. They are also making mice that lack midnolin to understand the protein's role in different cells and stages of development. The scientists say their finding has tantalizing translational potential. It may offer a pathway that researchers can harness to control levels of transcription factors, thus modulating gene expression, and in turn, associated processes in the body. "Protein degradation is a critical process and its deregulation underlies many disorders and diseases," including certain neurological and psychiatric conditions, as well as some cancers, Greenberg said. For example, when cells have too much or too little of transcription factors such as Fos, problems with learning and memory may arise. In multiple myeloma, cancer cells become addicted to the immune protein IRF4, so its presence can fuel the disease. The researchers are especially interested in identifying diseases that may be good candidates for the development of therapies that work through the midnolin-proteasome pathway. "One of the areas we are actively exploring is how to tune the specificity of the mechanism so it can specifically degrade proteins of interest," Gu said. Funding was provided by a National Mah Jongg League Fellowship from the Damon Runyon Cancer Research Foundation, a National Science Foundation Graduate Research Fellowship, and the National Institutes of Health (T32 HG002295; R01 NS115965; AG11085). Elledge is a founder of TScan Therapeutics, Maze Therapeutics, ImmuneID, and Mirimus, serves on the scientific advisory boards of Homology Medicines, ImmuneID, Maze Therapeutics, X-Chem, and TScan Therapeutics, and is an advisor for MPM Capital.

PharmaTher’s 5th FDA orphan drug designation for KETARX™ (ketamine) Phase 2 clinical study results to support proposed Phase 3 development of KETARX™ (ketamine) to treat Rett Syndrome for FDA approval via the 505(b)(2) regulatory pathway TORONTO, Feb. 02, 2023 (GLOBE NEWSWIRE) -- PharmaTher Holdings Ltd. (the “Company” or “PharmaTher”) (OTCQB: PHRRF) (CSE: PHRM), a leader in specialty ketamine pharmaceuticals, today announced that the U.S. Food and Drug Administration (“FDA”) has granted orphan drug designation to KETARX™ (racemic ketamine) for the treatment of Rett Syndrome, a rare genetic neurological disorder. Ketamine has been subject to a Phase 2 clinical trial (NCT03633058) for Rett syndrome. Unpublished results from this study will be evaluated to support a potential Phase 3 clinical study and obtain FDA agreement on a regulatory plan for approval via the 505(b)(2) regulatory pathway. PharmaTher currently holds five orphan drug designations granted by the FDA for KETARX™ (racemic ketamine), which include: Treatment of Rett Syndrome; Prevention of Ischemia-reperfusion injury from organ transplantation; Treatment of Status Epilepticus; Treatment of Amyotrophic Lateral Sclerosis; and Treatment of Complex Regional Pain Syndrome. “We are committed to unlocking the potential of KETARX™ for rare disorders, and the addition of the Rett syndrome program to our four FDA-approved orphan drug designations strengthens our position in leading the advancement of ketamine for unmet medical needs in mental health, neurological and pain disorders,” said Fabio Chianelli, CEO of PharmaTher. About Rett syndrome Currently, there is no known cure or FDA-approved drugs for treating Rett syndrome. According to the Rett Syndrome Foundation, Rett syndrome is a rare genetic neurological disorder that occurs almost exclusively in girls. It leads to severe impairments in their ability to speak, walk, eat, and even breathe easily. Prominent features of Rett syndrome include near constant repetitive hand movements and loss of purposeful hand use. Rett syndrome is usually recognized in children between 6 to 18 months. Rett syndrome is caused by mutations on the X chromosome on a gene called MECP2. Rett syndrome occurs worldwide in 1 of every 10,000 female births, and is much rarer in boys. Ketamine’s Potential In Rett syndrome Ketamine has the potential to treat Rett syndrome, which has been independently validated in two different laboratories in two different strains of Mecp2 mice and has completed a Phase 2 clinical trial with Rett syndrome, with results not published. The therapeutic potential of ketamine for treating Rett syndrome was first demonstrated by Dr. David M. Katz, Professor Emeritus, Department of Neurosciences, School of Medicine at CWRU, and colleagues, who found that treatment of heterozygous female Mecp2 mutant mice with a subanesthetic dose of ketamine (8 mg/kg) acutely reversed abnormalities in Fos expression and sensorimotor function [1]. Chronic administration of ketamine was also found to improve symptoms and extend lifespan in null male Mecp2 mutants [2]. The ability of low-dose ketamine to improve function across a broad range of symptoms may be related to its ability to increase cortical network activity, possibly by selective inhibition of GABAergic interneurons [3], as well as to decrease synaptic excitability in brainstem networks important for respiratory and autonomic control [4]. Thus, ketamine may be ideally suited to redress the imbalance between cortical and brainstem activity that characterizes the MeCP2-deficient brain. Moreover, in addition to its acute effects on circuit function, work in other disease models has shown that ketamine also rapidly stimulates dendritic growth, BDNF levels, and expression of key synaptic proteins [5, 6], at least in part through activation of mTOR signalling, which is deficient in Mecp2 mutants [7]. These findings suggest that, in addition to acute rescue of neurological function, ketamine also has the potential to promote synaptic repair in Rett syndrome by enhancing structural and functional connectivity, as previously shown in animal models of depression and stress [8]. The Orphan Drug Act grants special status to a drug or biological product to treat a rare disease or condition upon request of a sponsor. This status is referred to as orphan designation (or sometimes “orphan status”). The FDA grants orphan status to products that treat rare diseases, providing incentives to sponsors developing drugs or biologics. The FDA defines rare diseases as those affecting fewer than 200,000 people in the United States at any given time. Orphan drug designation would qualify ketamine for certain benefits and incentives, including seven years of marketing exclusivity if regulatory approval is ultimately received for the designated indication, potential tax credits for certain clinical drug testing costs, eligibility for orphan drug grants, and the waiver of the FDA New Drug Application filing fee of approximately $2.4 million. The Company previously announced that it has entered into an evaluation and exclusive option agreement (the “Agreement”) with Case Western Reserve University in the development and commercialization of the intellectual property of ketamine in the treatment of Rett Syndrome. About PharmaTher Holdings Ltd. PharmaTher Holdings Ltd. (OTCQB: PHRRF) (CSE: PHRM) is a specialty pharmaceutical company focused on developing and commercializing KETARX™ (racemic ketamine) for mental health, neurological and pain disorders. Learn more at PharmaTher.com. Contact: Fabio Chianelli Chief Executive Officer PharmaTher Holdings Ltd. Tel: 1-888-846-3171 Email: info@pharmather.com Website: Neither the Canadian Securities Exchange nor its Regulation Services Provider have reviewed or accept responsibility for the adequacy or accuracy of this release. Cautionary Statement This press release contains 'forward-looking information' within the meaning of applicable Canadian securities legislation. These statements relate to future events or future performance. The use of any of the words "could", "intend", "expect", "believe", "will", "projected", "estimated", "potential", "aim", “may” and similar expressions and statements relating to matters that are not historical facts are intended to identify forward-looking information and are based on PharmaTher Holdings Ltd. (the "Company") current belief or assumptions as to the outcome and timing of such future events. Forward-looking information is based on reasonable assumptions that have been made by the Company at the date of the information and is subject to known and unknown risks, uncertainties, and other factors that may cause actual results or events to differ materially from those anticipated in the forward-looking information. Given these risks, uncertainties and assumptions, you should not unduly rely on these forward-looking statements. The forward-looking information contained in this press release is made as of the date hereof, and Company is not obligated to update or revise any forward-looking information, whether as a result of new information, future events or otherwise, except as required by applicable securities laws. The foregoing statements expressly qualify any forward-looking information contained herein. Factors that could cause actual results to differ materially from those anticipated in these forward-looking statements are described under the caption "Risk Factors" in Company's management's discussion and analysis for the three and six months ended November 30, 2022 ("MD&A"), dated January 23, 2023, which is available on the Company's pro . 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