Post-traumatic stress disorder (PTSD) is a debilitating psychiatric condition that develops following exposure to a traumatic event. Individuals with this condition experience numerous physiological and behavioral alterations, including intrusive memories, avoidance of trauma-related stimuli, heightened anxiety, hypervigilance, impaired cognition, elevated resting heart rate and blood pressure, and altered neuroendocrine function, to name a few. In most patients, currently available pharmacological and psychological treatments are insufficient to alleviate the array of symptoms associated with the disorder. Thus, novel treatment options that can more effectively target the core etiology of PTSD are desperately needed. Recent work demonstrating the psychoplastogenic effects of psychedelics has reinvigorated research to examine their therapeutic potential in psychiatric conditions. Psilocybin, one psychedelic found in the Psilocybe genus of mushrooms, has exhibited promising antidepressant and anxiolytic effects in preclinical and clinical studies. The purpose of this review is to summarize the existing research that has examined the behavioral effects of psilocybin and link it to potential efficacy in treating PTSD-related symptoms. The proposed mechanisms for psilocybin's effects are then explored, as are the benefits and drawbacks for the agent's therapeutic use. Finally, the challenges faced by investigators aiming to study psilocybin as a therapeutic aid in future studies are discussed in order to shed light on this budding area of research. Significance Statement Current pharmacotherapy for PTSD is insufficient. Traditional antidepressants and anxiolytics help reduce symptom severity, but nonresponse rates often reach levels greater than 50%, emphasizing the need for more effective treatment options. The goal of this review is to summarize the existing evidence for and the potential mechanisms of the antidepressant and anxiolytic effects of psilocybin, a psychedelic compound found in the Psilocybe genus of mushrooms. We then relate the observed effects to psilocybin's potential use as a treatment for PTSD.
Inter-organ cross-talk contributes to the pathogenesis of various disorders, and drug development based on inter-organ cross-talk is attracting attention. The roles of nitric oxide (NO) derived from the NO synthases system (NOSs) in inter-organ cross-talk remain unclear. We have investigated this issue by using our mice deficient in all three NOSs (triple n/i/eNOSs-/- mice). We reported that 2/3 nephrectomized triple n/i/eNOSs-/- mice die suddenly because of early onset of myocardial infarction, suggesting the protective role of NO derived from NOSs in the cross-talk between the kidney and the heart. We studied the role of NO derived from NOSs expressed in the bone marrow in vascular lesion formation. Constrictive arterial remodeling and neointimal formation following unilateral carotid artery ligation were prominently aggravated in wild-type mice transplanted with triple n/i/eNOSs-/- bone marrow cells as compared with those with wild-type bone marrow cells, suggesting the protective role of NO derived from NOSs in the cross-talk between the bone marrow and the blood vessel. We further investigated the role of NO derived from NOSs expressed in the bone marrow in pulmonary hypertension. The extent of pulmonary hypertension after chronic hypoxic exposure was markedly exacerbated in wild-type mice underwent triple n/i/eNOSs-/- bone marrow transplantation as compared with those underwent wild-type bone marrow transplantation, suggesting the protective role of NO derived from NOSs in the cross-talk between the bone marrow and the lung. These lines of evidence demonstrate that systemic and myelocytic NOSs could be novel therapeutic targets for myocardial infarction, vascular disease, and pulmonary hypertension. Significance Statement We demonstrated in studies with triple n/i/eNOSs-/- mice that partial nephrectomy accelerates the occurrence of myocardial infarction induced by systemic NOSs deficiency, that myelocytic NOSs deficiency aggravates vascular lesion formation after unilateral carotid artery ligation, and that myelocytic NOSs deficiency exacerbates chronic hypoxia-induced pulmonary hypertension. These results suggest that NO derived from NOSs plays a protective role in cardiovascular inter-organ cross-talk, indicating that systemic and myelocytic NOSs could be important therapeutic targets for myocardial infarction, vascular disease, and pulmonary hypertension.
The Acute Respiratory Distress Syndrome (ARDS), often preceded by acute lung injury (ALI), is characterized by the accumulation of inflammatory fluid in the lung alveoli, leaky alveolar epithelium and endothelium, and overexpression of pro-inflammatory cytokines. This progression from ALI to ARDS is a major contributor to the high mortality observed in COVID-19 patients. The Spike protein of SARS-CoV-2 binds to lung ACE2 and, in addition to facilitating viral cell entry, it plays an important role in the development of ALI and ARDS, especially in the later phases of COVID-19 as well as long COVID. Protein tyrosine phosphatase (PTP) 4A3 is a key mediator of ARDS pathology. This study tested the hypothesis that targeting PTP4A3 would prevent COVID-19 associated ALI. Intratracheal administration of SARS-CoV-2 Spike protein Subunit 1 to K18-hACE2 transgenic mice expressing human ACE2 elicited pulmonary and systemic inflammation, leaky alveoli, overexpression of cytokines, structural lung injury and lung dysfunction; all these symptoms were ameliorated by the selective, allosteric inhibitor of PTP4A3, KVX-053. These findings provide the first evidence supporting a role for PTP4A3 in the development of SARS-CoV-2- mediated ALI. Significance Statement This study tested the hypothesis that targeting PTP4A3 would prevent COVID-19 associated ALI/ARDS. Intratracheal administration of SARS-CoV-2 Spike protein Subunit 1 to K18-hACE2 transgenic mice expressing human ACE2 elicited pulmonary and systemic inflammation, leaky alveoli, overexpression of cytokines and chemokines, structural lung injury and lung dysfunction; all these symptoms were ameliorated by the selective, allosteric inhibitor of PTP4A3, KVX-053. These findings suggest that this novel PTP4A3 inhibitor may be useful against COVID-19 and potentially other viral-induced ARDS.
Genetic loss-of-function mutations of Nav1.7 channel, abundantly expressed in peripheral nociceptive neurons, cause congenital insensitivity to pain (CIP) in humans, indicating that selective inhibition of the channel may lead to potential therapy of pain disorders. In this study, we investigated a novel compound, 5-chloro-N-(cyclopropylsulfonyl)-2-fluoro-4-(2-(8-(furan-2-ylmethyl)-8-azaspiro [4.5] decan-2-yl) ethoxy) benzamide (QLS-278) that inhibits Nav1.7 channel and exhibits anti-nociceptive activity. Compound QLS-278 exhibits inactivation- and concentration-dependent inhibition of macroscopic currents of Nav1.7 channels stably expressed in HEK293 cells with an IC50 of 1.2 {plus minus} 0.2 μM. QLS-278 causes a hyperpolarization shift of the channel inactivation and delays recovery from inactivation, without an obvious effect on voltage-dependent activation. In mouse DRG neurons, QLS-278 suppresses native TTX-sensitive Nav currents and also reduces neuronal firing. Moreover, QLS-278 dose-dependently relieves neuropathic pain induced by spared nerve injury and inflammatory pain induced by formalin without significant alteration of spontaneous locomotor activity in mice. Altogether, our identification of the novel compound QLS-278 may hold developmental potential for the treatment of chronic pain. Significance Statement QLS-278, a novel voltage-gated sodium Nav1.7 channel blocker, inhibits native TTX-S Na+ current and reduces action potential firings in DRG sensory neurons. QLS-278 also exhibits antinociceptive activity in mouse models of pain, thus demonstrating potential for the development of a treatment for chronic pain.