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Multiple sclerosis (MS) is a chronic and debilitating neurological disease that results in inflammatory demyelination. While endogenous remyelination helps to recover function, this restorative process tends to become less efficient over time. Currently, intense efforts aimed at the mechanisms that promote remyelination are being considered promising therapeutic approaches. The M1 muscarinic acetylcholine receptor (M1R) was previously identified as a negative regulator of oligodendrocyte differentiation and myelination. Here, we validate M1R as a target for remyelination by characterizing expression in human and rodent oligodendroglial cells (including those in human MS tissue) using a highly selective M1R probe. As a breakthrough to conventional methodology, we conjugated a fluorophore to a highly M1R selective peptide (MT7) which targets the M1R in the subnanomolar range. This allows for exceptional detection of M1R protein expression in the human CNS. More importantly, we introduce PIPE-307, a brain-penetrant, small-molecule antagonist with favorable drug-like properties that selectively targets M1R. We evaluate PIPE-307 in a series of in vitro and in vivo studies to characterize potency and selectivity for M1R over M2-5R and confirm the sufficiency of blocking this receptor to promote differentiation and remyelination. Further, PIPE-307 displays significant efficacy in the mouse experimental autoimmune encephalomyelitis model of MS as evaluated by quantifying disability, histology, electron microscopy, and visual evoked potentials. Together, these findings support targeting M1R for remyelination and support further development of PIPE-307 for clinical studies., Competing Interests: Competing interests statement:M.M.P., K.I.L., K.J.S., G.C.E., A.R.B., J.R.R., J.M.B., C.S.B., A.C.C., and D.S.L. are current employees of Contineum Therapeutics and hold financial shares of Contineum Therapeutics. Contineum Therapeutics owns patent rights to PIPE-307.

Multiple sclerosis (MS) is a chronic neurological disease characterized by inflammatory demyelination that disrupts neuronal transmission resulting in neurodegeneration progressive disability. While current treatments focus on immunosuppression to limit inflammation and further myelin loss, no approved therapies effectively promote remyelination to mitigate the progressive disability associated with chronic demyelination. Lysophosphatidic acid (LPA) is a pro-inflammatory lipid that is upregulated in MS patient plasma and cerebrospinal fluid (CSF). LPA activates the LPA1 receptor, resulting in elevated CNS cytokine and chemokine levels, infiltration of immune cells, and microglial/astrocyte activation. This results in a neuroinflammatory response leading to demyelination and suppressed remyelination. A medicinal chemistry effort identified PIPE-791, an oral, brain-penetrant, LPA1 antagonist. PIPE-791 was characterized in vitro and in vivo and was found to be a potent, selective LPA1 antagonist with slow receptor off-rate kinetics. In vitro, PIPE-791 induced OPC differentiation and promoted remyelination following a demyelinating insult. PIPE-791 further mitigated the macrophage-mediated inhibition of OPC differentiation and inhibited microglial and fibroblast activation. In vivo, the compound readily crossed the blood-brain barrier and blocked LPA1 in the CNS after oral dosing. Direct dosing of PIPE-791 in vivo increased oligodendrocyte number, and in the mouse experimental autoimmune encephalomyelitis (EAE) model of MS, we observed that PIPE-791 promoted myelination, reduced neuroinflammation, and restored visual evoked potential latencies (VEP). These findings support targeting LPA1 for remyelination and encourage development of PIPE-791 for treating MS patients with advantages not seen with current immunosuppressive disease modifying therapies., (© 2024. The Author(s).)

Structure-activity relationship studies led to the discovery of PIPE-3297, a fully efficacious and selective kappa opioid receptor (KOR) agonist. PIPE-3297, a potent activator of G-protein signaling (GTPγS EC 50 = 1.1 nM, 91% E max ), did not elicit a β-arrestin-2 recruitment functional response ( E max < 10%). Receptor occupancy experiments performed with the novel KOR radiotracer [ 3 H]-PIPE-3113 revealed that subcutaneous (s.c.) administration of PIPE-3297 at 30 mg/kg in mice achieved 90% occupancy of the KOR in the CNS 1 h post dose. A single subcutaneous dose of PIPE-3297 in healthy mice produced a statistically significant increase of mature oligodendrocytes ( P < 0.0001) in the KOR-enriched striatum, an effect that was not observed in animals predosed with the selective KOR antagonist norbinaltorphimine. An equivalent dose given to mice in an open-field activity-monitoring system revealed a small KOR-independent decrease in total locomotor activity versus vehicle measured between 60 and 75 min post dose. Daily doses of PIPE-3297 at both 3 and 30 mg/kg s.c. reduced the disease score in the mouse experimental autoimmune encephalomyelitis (EAE) model. Visually evoked potential (VEP) N1 latencies were also significantly improved versus vehicle in both dose groups, and latencies matched those of untreated animals. Taken together, these findings highlight the potential therapeutic value of functionally selective G-protein KOR agonists in demyelinating disease, which may avoid the sedating side effects typically associated with classical nonbiased KOR agonists.

Respiratory failure in COVID-19 is characterized by widespread disruption of the lung's alveolar gas exchange interface. To elucidate determinants of alveolar lung damage, we performed epithelial and immune cell profiling in lungs from 24 COVID-19 autopsies and 43 uninfected organ donors ages 18-92 years. We found marked loss of type 2 alveolar epithelial (T2AE) cells and increased perialveolar lymphocyte cytotoxicity in all fatal COVID-19 cases, even at early stages before typical patterns of acute lung injury are histologically apparent. In lungs from uninfected organ donors, there was also progressive loss of T2AE cells with increasing age, which may increase susceptibility to COVID-19-mediated lung damage in older individuals. In the fatal COVID-19 cases, macrophage infiltration differed according to the histopathological pattern of lung injury. In cases with acute lung injury, we found accumulation of CD4+ macrophages that expressed distinctly high levels of T cell activation and costimulation genes and strongly correlated with increased extent of alveolar epithelial cell depletion and CD8+ T cell cytotoxicity. Together, our results show that T2AE cell deficiency may underlie age-related COVID-19 risk and initiate alveolar dysfunction shortly after infection, and we define immune cell mediators that may contribute to alveolar injury in distinct pathological stages of fatal COVID-19.

Purees are often recommended for older adults in residential aged care facilities (RACFs) to target swallowing difficulties and nutrition. However, they lack appeal and may have negative impacts on nutritional intake. This study investigated the subjective experiences and objective swallowing function and safety of older adults in response to a modified puree. Twenty-eight residents from three RACFs whose regular diets consisted of purees were recruited. Purees were modified to improve visual appeal by adding a commercial enzyme gellant. Each participant was observed during three puree and three modified puree meals, and completed a brief questionnaire after each meal. A videofluoroscopic swallowing study (VFSS) was performed with 16 of the participants. Compared to purees, modified purees were observed to be easier for oral processing and intake amount was higher, but participants required assistance more often and mealtimes were longer. Participants did not show preference for either type of puree. VFSS showed similar swallowing responses between the two puree types; however, a distinction was observed for modified pureed meat compared to other ingredients. Modifying puree meals in RACFs is a feasible approach to improve nutritional intake while maintaining swallowing safety, but their appeal to consumers is not definitive.

The discovery of PIPE-359, a brain-penetrant and selective antagonist of the muscarinic acetylcholine receptor subtype 1 is described. Starting from a literature-reported M 1 antagonist, linker replacement and structure-activity relationship investigations of the eastern 1-(pyridinyl)piperazine led to the identification of a novel, potent, and selective antagonist with good MDCKII-MDR1 permeability. Continued semi-iterative positional scanning facilitated improvements in the metabolic and hERG profiles, which ultimately delivered PIPE-359. This advanced drug candidate exhibited robust efficacy in mouse myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalitis (EAE), a preclinical model for multiple sclerosis., Competing Interests: The authors declare no competing financial interest., (© 2020 American Chemical Society.)

Immune responses in diverse tissue sites are critical for protective immunity and homeostasis. Here, we investigate how tissue localization regulates the development and function of human natural killer (NK) cells, innate lymphocytes important for anti-viral and tumor immunity. Integrating high-dimensional analysis of NK cells from blood, lymphoid organs, and mucosal tissue sites from 60 individuals, we identify tissue-specific patterns of NK cell subset distribution, maturation, and function maintained across age and between individuals. Mature and terminally differentiated NK cells with enhanced effector function predominate in blood, bone marrow, spleen, and lungs and exhibit shared transcriptional programs across sites. By contrast, precursor and immature NK cells with reduced effector capacity populate lymph nodes and intestines and exhibit tissue-resident signatures and site-specific adaptations. Together, our results reveal anatomic control of NK cell development and maintenance as tissue-resident populations, whereas mature, terminally differentiated subsets mediate immunosurveillance through diverse peripheral sites. VIDEO ABSTRACT., Competing Interests: Declaration of Interests The authors declare no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Due to the lack of validated assessment tools for motives of non-suicidal self-injury behaviors in the Chinese contexts, this study aims to evaluate the psychometric properties of the Chinese version of the Functional Assessment of Self-Mutilation (C-FASM). A total of 345 secondary school students (mean age = 11.41 years), who reported non-suicidal self-injury in the past year, voluntarily participated in the questionnaire survey. Confirmatory factor analysis results supported a second-order model of 4 motivational factors. The overall scale scores had significant correlations with depression, anxiety, impulsiveness, self-esteem, social support, and suicidal ideation. The internal consistency of the scale was also satisfactory. The C-FASM is a valid and reliable instrument for assessing non-suicidal self-injury among nonclinical Chinese adolescents.

Chinese herbal medicine (CHM), either in single herb or in herbal formula, has been used to treat insomnia for more than 2000 years. A systematic review including Chinese and English literature of randomized controlled trials was conducted to examine the efficacy, safety, and composition of CHM for insomnia. Among the 217 studies we have reviewed, only eight had a Jadad score ≥3, and seven out of these eight studies had at least one domain with high risks of bias. Meta-analyses of the studies with Jadad score ≥3 found that CHM was similar to Western medication (three studies) and placebo (three studies) in treating insomnia. Due to the poor methodological quality of the studies and the small number of trials included in meta-analyses, the current evidence is insufficient to support the efficacy of CHM for insomnia. The frequency of adverse events associated with CHM was similar to that of placebo, but lower than with Western medication. Gui Pi Tang was the most commonly used standardized formula, while Suan Zao Ren (Ziziphus jujuba) was the most frequently used single herb. Further studies with a double-blind placebo-controlled design are needed to accurately determine the benefits and risks of CHM for insomnia., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Previous randomized controlled trials (RCTs) have shown that acupuncture may be efficacious for insomnia. Instead of needling, acupressure, reflexology, and auricular acupressure are procedures involving physical pressure on acupoints or reflex areas. These variants of acupuncture are gaining popularity, perhaps due to their non-invasive nature. A systematic review has therefore been conducted to examine their efficacy and safety for insomnia. Two independent researchers searched five English and 10 Chinese databases from inception to May 2010. Forty RCTs were identified for analysis. Only 10 studies used sham controls, four used double-blind design, nine studies scored three or more by the Jadad scale, and all had at least one domain with high risk of bias. Meta-analyses of the moderate-quality RCTs found that acupressure as monotherapy fared marginally better than sham control. Studies that compared auricular acupressure and sham control showed equivocal results. It was also found that acupressure, reflexology, or auricular acupressure as monotherapy or combined with routine care was significantly more efficacious than routine care or no treatment. Owing to the methodological limitations of the studies and equivocal results, the current evidence does not allow a clear conclusion on the benefits of acupressure, reflexology, and auricular acupressure for insomnia., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A systematic review was conducted to examine traditional Chinese medicine (TCM) patterns commonly diagnosed in subjects with insomnia and clinical features associated with the TCM patterns, and an insomnia symptom checklist for TCM diagnostic purpose was developed based on the review. Two independent researchers searched the China Academic Journals Full-Text Database and 10 English databases. A total of 103 studies and 9499 subjects were analyzed. There was a wide variation in terminology relating to symptomatology and TCM pattern. We identified 69 patterns, with the top 3 patterns (i.e., deficiency of both the heart and spleen, hyperactivity of fire due to yin deficiency, and liver-qi stagnation transforming into fire) and the top 10 patterns covering 51.8% and 77.4% of the 9499 subjects, respectively. There were 19 sleep-related, 92 non-sleep-related, 14 tongue, and 7 pulse features included as diagnostic criteria of the top 10 TCM patterns for insomnia. Excessive dreaming, dizziness, red tongue, and fine pulse were the most common sleep-related, non-sleep-related, tongue, and pulse features. Overlapping symptomatology between the TCM patterns was present. A standardized symptom checklist consisted of 92 items, including 13 sleep-related, 61 non-sleep-related, 11 tongue, and 7 pulse items, holds promise as a diagnostic tool and merits further validation.

Traditional Chinese medicine (TCM) treatments are often prescribed based on individuals' pattern diagnoses. A systematic review of Chinese and English literatures on TCM pattern differentiation, treatment principle, and pattern-based treatment for insomnia has therefore been conducted. A total of 227 studies, 17916 subjects, and 87 TCM patterns were analyzed. There was a limited consistency in pattern-based TCM treatment of insomnia across practitioners. Except for Gui Pi Tang, An Shen Ding Zhi Wan, and Wen Dan Tang which were used more commonly for deficiency of both the heart and spleen, internal disturbance of phlegm-heat, and qi deficiency of the heart and gallbladder, respectively, the selection of herbal formula for other patterns and pattern-based prescription of individual herbs and acupoints were not consistent. Suanzaoren (Semen Z. spinosae), Fuling (Poria), Yejiaoteng (Caulis P. multiflori), Gancao (Radix Glycyrrhizae), Baishao (Radix P. alba), Shenmen (HT7), Yintang (EX-HN3), Sanyinjiao (SP6), Baihui (GV20), Anmian (EX-HN22), and Sishencong (EX-HN1) were commonly used, but nonspecifically for many patterns. Treatment principles underlying herb and acupoint selection were seldom reported. Although many studies were reviewed, the study quality and diagnostic process were inadequate. More high quality studies are needed to examine the additional benefits of pattern differentiation and pattern-based TCM treatment.

Local translation of dendritic mRNAs plays an important role in neuronal development and synaptic plasticity. Although several hundred putative dendritic transcripts have been identified in the hippocampus, relatively few have been verified by in situ hybridization and thus remain uncharacterized. One such transcript encodes the protein neuronatin. Neuronatin has been shown to regulate calcium levels in non-neuronal cells such as pancreatic or embryonic stem cells, but its function in mature neurons remains unclear. Here we report that neuronatin is translated in hippocampal dendrites in response to blockade of action potentials and NMDA-receptor dependent synaptic transmission by TTX and APV. Our study also reveals that neuronatin can adjust dendritic calcium levels by regulating intracellular calcium storage. We propose that neuronatin may impact synaptic plasticity by modulating dendritic calcium levels during homeostatic plasticity, thereby potentially regulating neuronal excitability, receptor trafficking, and calcium dependent signaling.

Retinoic acid (RA) plays important roles in development by modulating gene transcription through nuclear receptor activation. Increasing evidence supports a role for RA and RA receptors (RARs) in synaptic plasticity in the brain. We have recently reported that RA mediates a type of homeostatic synaptic plasticity through activation of dendritic protein synthesis, a process that requires dendritically localized RARalpha and is independent of transcriptional regulation. The molecular basis of this translational regulation by RA/RARalpha signaling, however, is unknown. Here we show that RARalpha is actively exported from the nucleus. Cytoplasmic RARalpha acts as an RNA-binding protein that associates with a subset of mRNAs, including dendritically localized glutamate receptor 1 (GluR1) mRNA. This binding is mediated by the RARalpha carboxyl terminal F-domain and specific sequence motifs in the 5'UTR of the GluR1 mRNA. Moreover, RARalpha association with the GluR1 mRNA directly underlies the translational control of GluR1 by RA: RARalpha represses GluR1 translation, while RA binding to RARalpha reduces its association with the GluR1 mRNA and relieves translational repression. Taken together, our results demonstrate a ligand-gated translational regulation mechanism mediated by a non-genomic function of RA/RARalpha signaling.

Normal brain function requires that the overall synaptic activity in neural circuits be kept constant. Long-term alterations of neural activity lead to homeostatic regulation of synaptic strength by a process known as synaptic scaling. The molecular mechanisms underlying synaptic scaling are largely unknown. Here, we report that all-trans retinoic acid (RA), a well-known developmental morphogen, unexpectedly mediates synaptic scaling in response to activity blockade. We show that activity blockade increases RA synthesis in neurons and that acute RA treatment enhances synaptic transmission. The RA-induced increase in synaptic strength is occluded by activity blockade-induced synaptic scaling. Suppression of RA synthesis prevents synaptic scaling. This form of RA signaling operates via a translation-dependent but transcription-independent mechanism, causes an upregulation of postsynaptic glutamate receptor levels, and requires RARalpha receptors. Together, our data suggest that RA functions in homeostatic plasticity as a signaling molecule that increases synaptic strength by a protein synthesis-dependent mechanism.

Homeostatic plasticity is thought to play an important role in maintaining the stability of neuronal circuits. During one form of homeostatic plasticity, referred to as synaptic scaling, activity blockade leads to a compensatory increase in synaptic transmission by stimulating in dendrites the local translation and synaptic insertion of the AMPA receptor subunit GluR1. We have previously shown that all-trans retinoic acid (RA) mediates activity blockade-induced synaptic scaling by activating dendritic GluR1 synthesis and that this process requires RARalpha, a member of the nuclear RA receptor family. This result raised the question of where RARalpha is localized in dendrites and whether its localization is regulated by RA and/or activity blockade. Here, we show that activity blockade or RA treatment in neurons enhances the concentration of RARalpha in the dendritic RNA granules and activates local GluR1 synthesis in these RNA granules. Importantly, the same RNA granules that contain RARalpha also exhibit an accumulation of GluR1 protein but with a much slower time course than that of RARalpha, suggesting that the former regulates the latter. Taken together, our results provide a direct link between dendritically localized RARalpha and local GluR1 synthesis in RNA granules during RA-mediated synaptic signaling in homeostatic synaptic plasticity.

The regulated translation of localized mRNAs in neurons provides a mechanism for spatially restricting gene expression in a synapse-specific manner. To identify the population of mRNAs present in distal neuronal processes of rodent hippocampal neurons, we grew neurons on polycarbonate filters etched with 3 microm pores. Although the neuronal cell bodies remained on the top surface of the filters, dendrites, axons, and glial processes penetrated through the pores to grow along the bottom surface of the membrane where they could be mechanically separated from cell bodies. Quantitative PCR and immunochemical analyses of the process preparation revealed that it was remarkably free of somatic contamination. Microarray analysis of RNA isolated from the processes identified over 100 potentially localized mRNAs. In situ hybridization studies of 19 of these transcripts confirmed that all 19 were present in dendrites, validating the utility of this approach for identifying dendritically localized transcripts. Many of the identified mRNAs encoded components of the translational machinery and several were associated with the RNA-binding protein Staufen. These findings indicate that there is a rich repertoire of mRNAs whose translation can be locally regulated and support the emerging idea that local protein synthesis serves to boost the translational capacity of synapses.

By means of a sensitive competition assay, serum, urine, and CSF from patients with Huntington's disease (HD) and controls were tested for the presence of molecules capable of displacing radioactive kainic acid (KA) from rat brain receptors. No difference was found between HD and control samples. It is unlikely that systemic production of an endogenous toxin structurally related to KA occurs in HD.