Increased orexin expression promotes sleep/wake disturbances in the SOD1-G93A mouse model of amyotrophic lateral sclerosis

Low toxicity contributes to Sporothrix globosa invade the skin of patients in low-epidemic areas of China

OBJECTIVE

This study aims to assess the clinical characteristics of sporotrichosis in low-endemic areas of China, including the prevalence geography, genotypic traits of patients, clinical manifestations, and strain virulence and drug sensitivities. The objective is to improve the currently used clinical management strategies for sporotrichosis.

METHODS

Retrospective data were collected from patients diagnosed with sporotrichosis through fungal culture identification. The isolates from purified cultures underwent identification using CAL (Calmodulin) gene sequencing. Virulence of each strain was assessed using a Galleria mellonella (G. mellonella) larvae infection model. In vitro susceptibility testing against commonly used clinical antifungal agents for sporotrichosis was conducted following CLSI criteria.

RESULTS

In our low-endemic region for sporotrichosis, the majority of cases (23) were observed in middle-aged and elderly women with a history of trauma, with a higher incidence during winter and spring. All clinical isolates were identified as Sporothrix globosa (S. globosa). The G. mellonella larvae infection model indicated independent and dose-dependent virulence among strains, with varying toxicity levels demonstrated by the degree of melanization of the G. mellonella. Surprisingly, lymphocutaneous types caused by S. globosa exhibited lower in vitro virulence but were more common in affected skin. In addition, all S.globosa strains displayed high resistances to fluconazole, while remaining highly susceptible to terbinafine, itraconazole and amphotericin B.

CONCLUSION

Given the predominance of elderly women engaged in agricultural labour in our region, which is a low-epidemic areas, they should be considered as crucial targets for sporotrichosis monitoring. S. globosa appears to be the sole causative agent locally. However, varying degrees of melanization in larvae were observed among these isolates, indicating a divergence in their virulence. Itraconazole, terbinafine and amphotericin B remain viable first-line antifungal options for treating S.globosa infection.

Clinical usefulness of dual orexin receptor antagonism beyond insomnia: Neurological and psychiatric comorbidities

Orexin is a neurotransmitter produced by a small group of hypothalamic neurons. Besides its well-known role in the regulation of the sleep-wake cycle, the orexin system was shown to be relevant in several physiological functions including cognition, mood and emotion modulation, and energy homeostasis. Indeed, the implication of orexin neurotransmission in neurological and psychiatric diseases has been hypothesized via a direct effect exerted by the projections of orexin neurons to several brain areas, and via an indirect effect through orexin-mediated modulation of sleep and wake. Along with the growing evidence concerning the use of dual orexin receptor antagonists (DORAs) in the treatment of insomnia, studies assessing their efficacy in insomnia comorbid with psychiatric and neurological diseases have been set in order to investigate the potential impact of DORAs on both sleep-related symptoms and disease-specific manifestations. This narrative review aimed at summarizing the current evidence on the use of DORAs in neurological and psychiatric conditions comorbid with insomnia, also discussing the possible implication of modulating the orexin system for improving the burden of symptoms and the pathological mechanisms of these disorders. Target searches were performed on PubMed/MEDLINE and Scopus databases and ongoing studies registered on Clinicaltrials.gov were reviewed. Despite some contradictory findings, preclinical studies seemingly support the possible beneficial role of orexin antagonism in the management of the most common neurological and psychiatric diseases with sleep-related comorbidities. However, clinical research is still limited and further studies are needed for corroborating these promising preliminary results.

Sleep Disturbances as a Potential Risk Factor for Deterioration of Respiratory Function in Patients with Amyotrophic Lateral Sclerosis

Objectives

Sleep disturbances are common in amyotrophic lateral sclerosis (ALS). However, previous studies have explored sleep quality at the cross-sectional level and the longitudinal variability characteristics are currently unknown. Our study aimed to longitudinally explore the effect of sleep quality on disease progression in patients with ALS.

Methods

All enrolled patients with ALS were first diagnosed and completed the 6- and 12-month follow-ups. Subjective sleep disturbance was assessed using the Pittsburgh Sleep Quality Index (PSQI). Based on the PSQI score at baseline, patients with ALS were classified as poor sleepers (PSQI >5) and good sleepers (PSQI ≤5). Disease progression was assessed using the rate of disease progression, the absolute change from baseline forced vital capacity (ΔFVC) and the percentage change from baseline FVC (ΔFVC%) over the follow-up period.

Results

Sixty-three patients were included in the study, 24 (38.1%) were poor sleepers and 39 were good sleepers. The percentage of patients with poor sleep quality was 38.1% at baseline, increasing to 60.3% and 74.6% at 6- and 12-month, respectively. Compared to good sleepers, ΔFVC and ΔFVC% values were greater in poor sleepers (P < 0.001 and P = 0.001, respectively). Poor sleep quality at diagnosis is associated with rapid deterioration of respiratory function during disease progression.

Conclusions

Sleep disturbances maybe a potential risk factor for deterioration of respiratory function in patients with ALS. The role of sleep disturbances in disease progression deserves attention, and early assessment and intervention may slow disease progression and improve life quality of patients with ALS.

Targeting the orexin/hypocretin system for the treatment of neuropsychiatric and neurodegenerative diseases: from animal to clinical studies

Orexins (also known as hypocretins) are neuropeptides located exclusively in hypothalamic neurons that have extensive projections throughout the central nervous system and bind two different G protein-coupled receptors (OX1R and OX2R). Since its discovery in 1998, the orexin system has gained the interest of the scientific community as a potential therapeutic target for the treatment of different pathological conditions. Considering previous basic science research, a dual orexin receptor antagonist, suvorexant, was the first orexin agent to be approved by the US Food and Drug Administration to treat insomnia. In this review, we discuss and update the main preclinical and human studies involving the orexin system with several psychiatric and neurodegenerative diseases. This system constitutes a nice example of how basic scientific research driven by curiosity can be the best route to the generation of new and powerful pharmacological treatments.

Michael acceptor molecules in natural products and their mechanism of action

Purpose: Michael receptor molecules derived from plants are biologically active due to electrophilic groups in their structure. They can target nucleophilic residues on disease-related proteins, with significant therapeutic effects and low toxicity for many diseases. They provide a good option for relevant disease treatment. The aim of this study is to summarize the existing MAMs and their applications, and lay a foundation for the application of Michael receptor molecules in life science in the future. Methods: This review summarizes the published studies on Michael receptor molecules isolated from plants in literature databases such as CNKI, Wanfang Data, PubMed, Web of Science, ScienceDirect, and Wiley. Latin names of plants were verified through https://www.iplant.cn/. All relevant compound structures were verified through PubChem and literature, and illustrated with ChemDraw 20.0. Result: A total of 50 Michael receptor molecules derived from various plants were discussed. It was found that these compounds have similar pharmacological potential, most of them play a role through the Keap1-Nrf2-ARE pathway and the NF-κB pathway, and have biological activities such as antioxidant and anti-inflammatory. They can be used to treat inflammatory diseases and tumors. Conclusion: The Michael receptor molecule has electrophilicity due to its unsaturated aldehyde ketone structure, which can combine with nucleophilic residues on the protein to form complexes and activate or inhibit the protein pathway to play a physiological role. Michael receptor molecules can regulate the Keap1-Nrf2-ARE pathway and the NF-κB pathway. Michael receptor molecules can be used to treat diseases such as inflammation, cancer, oxidative stress, etc.

SIRT1 Interacts with Prepro-Orexin in the Hypothalamus in SOD1G93A Mice

The participation of silent mating type information regulation 2 homolog 1 (SIRT1) in amyotrophic lateral sclerosis (ALS) has been reported in many studies. However, the role of the expression and function of SIRT1 in the hypothalamus in ALS remains unknown. In the current study, we performed western blot, co-immunoprecipitation and immunofluorescence analyses to determine the expression and in-depth mechanism of SIRT1 in the hypothalamus in SOD1G93A transgenic mice. We found that SIRT1 was overexpressed in the hypothalamus after motor symptom onset. In addition, SIRT1 interacted with prepro-orexin, a molecule involved in energy balance and the sleep/wake cycle, in both preclinical and clinical ALS regardless of whether SIRT1 levels were elevated. These findings indicate that SIRT1 might participate in sleep and metabolic changes in ALS, suggesting that SIRT1 is a new target for ALS treatment.

MRI Volumetric Analysis of the Thalamus and Hypothalamus in Amyotrophic Lateral Sclerosis

Background: Increasing evidence has shown that amyotrophic lateral sclerosis (ALS) can result in abnormal energy metabolism and sleep disorders, even before motor dysfunction. Although the hypothalamus and thalamus are important structures in these processes, few ALS studies have reported abnormal MRI structural findings in the hypothalamus and thalamus.

Purpose: We aimed to investigate volumetric changes in the thalamus and hypothalamus by using the automatic brain structure volumetry tool AccuBrain^®.

Methods: 3D T1-weighted magnetization-prepared gradient echo imaging (MPRAGE) scans were acquired from 16 patients with ALS with normal cognitive scores and 16 age-, sex- and education-matched healthy controls. Brain tissue and structure volumes were automatically calculated using AccuBrain^®.

Results: There were no significant differences in bilateral thalamic (F = 1.31, p = 0.287) or hypothalamic volumes (F = 1.65, p = 0.213) between the ALS and control groups by multivariate analysis of covariance (MANCOVA). Left and right hypothalamic volumes were correlated with whole-brain volume in patients with ALS (t = 3.19, p = 0.036; t = 3.03, p = 0.044), while the correlation between age and bilateral thalamic volumes tended to be significant after Bonferroni correction (t = 2.76, p = 0.068; t = 2.83, p = 0.06). In the control group, left and right thalamic volumes were correlated with whole-brain volume (t = 4.26, p = 0.004; t = 4.52, p = 0.004).

Conclusion: Thalamic and hypothalamic volumes did not show differences between patients with normal frontotemporal function ALS and healthy controls, but further studies are still needed.

Daytime sleepiness might increase the risk of ALS: a 2-sample Mendelian randomization study

BACKGROUND

Observational studies have indicated that there is a high prevalence of habitual sleep disturbances in amyotrophic lateral sclerosis (ALS). However, the actual relationship between these symptoms and ALS remains unclear.

METHODS

We used 2-sample Mendelian randomization to determine whether the sleep disturbances associated with ALS are also related to the risk of ALS. The summary statistics we used were from recent, large genome-wide association studies on daytime sleepiness and other night sleep traits (n = 85,670-452,071) and ALS (n = 20,806 cases, n = 59,804 controls). The inverse variance-weighted (IVW) method was used as the main method for assessing causality.

RESULTS

Daytime sleepiness might increase the risk of ALS (IVW odds ratio = 2.45, 95% confidence interval: 1.15-5.21; P = 0.020). ALS was not associated with sleep efficiency, number of sleep episodes or sleep duration.

CONCLUSIONS

Our results provide novel evidence that daytime sleepiness increases the risk of ALS and points out the importance of daytime sleepiness that often goes unnoticed in ALS.

Three Pillars of Automated Home-Cage Phenotyping of Mice: Novel Findings, Refinement, and Reproducibility Based on Literature and Experience

Animal models of neurodegenerative and neuropsychiatric disorders require extensive behavioral phenotyping. Currently, this presents several caveats and the most important are: (i) rodents are nocturnal animals, but mostly tested during the light period; (ii) the conventional behavioral experiments take into consideration only a snapshot of a rich behavioral repertoire; and (iii) environmental factors, as well as experimenter influence, are often underestimated. Consequently, serious concerns have been expressed regarding the reproducibility of research findings on the one hand, and appropriate welfare of the animals (based on the principle of 3Rs-reduce, refine and replace) on the other hand. To address these problems and improve behavioral phenotyping in general, several solutions have been proposed and developed. Undisturbed, 24/7 home-cage monitoring (HCM) is gaining increased attention and popularity as demonstrating the potential to substitute or complement the conventional phenotyping methods by providing valuable data for identifying the behavioral patterns that may have been missed otherwise. In this review, we will briefly describe the different technologies used for HCM systems. Thereafter, based on our experience, we will focus on two systems, IntelliCage (NewBehavior AG and TSE-systems) and Digital Ventilated Cage (DVC®, Tecniplast)-how they have been developed and applied during recent years. Additionally, we will touch upon the importance of the environmental/experimenter artifacts and propose alternative suggestions for performing phenotyping experiments based on the published evidence. We will discuss how the integration of telemetry systems for deriving certain physiological parameters can help to complement the description of the animal model to offer better translation to human studies. Ultimately, we will discuss how such HCM data can be statistically interpreted and analyzed.

Study on sleep-wake disorders in patients with genetic and non-genetic amyotrophic lateral sclerosis

OBJECTIVE

To study the frequency and clinical features of sleep disturbances in amyotrophic lateral sclerosis (ALS) patients and compare sleep disorders between ALS with and without mutations.

METHODS

In this case-control study, 204 ALS patients and 206 controls were included. We evaluated sleep quality using Pittsburgh Sleep Quality Index (PSQI). Excessive daytime sleepiness (EDS) was diagnosed according to Epworth Sleepiness Scale (ESS). Other characteristics, including rapid eye movement sleep behaviour disorder, restless legs syndrome (RLS), cognitive and psychological impairments, were also evaluated. All ALS patients underwent whole exome sequencing analysis to screen for ALS mutations and were divided into genetic ALS and non-genetic ALS subgroups based on the genetic testing results.

RESULTS

A total of 114 men and 90 women ALS patients, with a mean onset age of 53.5±9.9 years, were included in this study. There were 21 mutations detected, contributing to 46.6% of familial amyotrophic lateral sclerosis (FALS) and 7.4% of sporadic amyotrophic lateral sclerosis (SALS). The PQSI and ESS scores were higher in ALS patients than in controls (PSQI 6.0 (3.0,10.0) vs 3.5 (2.0,5.0) (p<0.01); ESS 6.0 (3.0,10.0) vs 4.0 (3.0,8.0) (p<0.01), respectively). RLS was more frequent in ALS patients than in controls (p<0.01). Genetic ALS patients were more likely to show EDS than non-genetic ALS patients (adjusted OR 5.2, p<0.01). Genetic ALS scored lower on Revised ALS Functional Rating Scale, and higher on PSQI and ESS than non-genetic ALS (p<0.01).

CONCLUSIONS

In the current study, ALS patients with mutations were more likely to have sleep-wake disturbances than were those without mutations. The former group may benefit more from sleep management.

A Non-invasive Digital Biomarker for the Detection of Rest Disturbances in the SOD1G93A Mouse Model of ALS

Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disease that affects both central and peripheral nervous system, leading to the degeneration of motor neurons, which eventually results in muscle atrophy, paralysis, and death. Sleep disturbances are common in patients with ALS, leading to even further deteriorated quality of life. Investigating methods to potentially assess sleep and rest disturbances in animal models of ALS is thus of crucial interest. We used an automated home cage monitoring system (DVC®) to capture irregular activity patterns that can potentially be associated with sleep and rest disturbances and thus to the progression of ALS in the SOD1G93A mouse model. DVC® enables non-intrusive 24/7 long term animal activity monitoring, which we assessed together with body weight decline and neuromuscular function deterioration measured by grid hanging and grip strength tests in male and female mice from 7 until 24 weeks of age. We show that as the ALS progresses over time in SOD1G93A mice, activity patterns start becoming irregular, especially during day time, with frequent activity bouts that are neither observed in control mice nor in SOD1G93A at a younger age. The increasing irregularities of activity pattern are quantitatively captured by designing a novel digital biomarker, referred to as Regularity Disruption Index (RDI). We show that RDI is a robust measure capable of detecting home cage activity patterns that could be related to rest/sleep-related disturbances during the disease progression. Moreover, the RDI rise during the early symptomatic stage parallels grid hanging and body weight decline. The non-intrusive long-term continuous monitoring of animal activity enabled by DVC® has been instrumental in discovering novel activity patterns potentially correlated, once validated, with sleep and rest disturbances in the SOD1G93A mouse model of the ALS disease.

Orexins role in neurodegenerative diseases: From pathogenesis to treatment

Orexin is a neurotransmitter that mainly regulates sleep/wake cycle. In addition to its sleep cycle regulatory role, it is involved in regulation of attention, energy homeostasis, neurogenesis and cognition. Several evidences has shown the involvement of orexin in narcolepsy, but there are also growing evidences that shows the disturbance in orexin system in neurodegenerative diseases including Alzheimer's, Parkinson's, Epilepsy, Huntington's diseases and Amyotrophic lateral sclerosis. Pathogenesis and clinical symptoms of these disorders can be partly attributed from orexin system imbalance. However, there are controversial reports on the exact relationship between orexin and these neurodegenerative diseases. Therefore, the aim of this review is to summarize the current evidences regarding the role of orexin in these neurodegenerative diseases.

Physiological changes in neurodegeneration - mechanistic insights and clinical utility

The effects of neurodegenerative syndromes extend beyond cognitive function to involve key physiological processes, including eating and metabolism, autonomic nervous system function, sleep, and motor function. Changes in these physiological processes are present in several conditions, including frontotemporal dementia, amyotrophic lateral sclerosis, Alzheimer disease and the parkinsonian plus conditions. Key neural structures that mediate physiological changes across these conditions include neuroendocrine and hypothalamic pathways, reward pathways, motor systems and the autonomic nervous system. In this Review, we highlight the key changes in physiological processing in neurodegenerative syndromes and the similarities in these changes between different progressive neurodegenerative brain conditions. The changes and similarities between disorders might provide novel insights into the human neural correlates of physiological functioning. Given the evidence that physiological changes can arise early in the neurodegenerative process, these changes could provide biomarkers to aid in the early diagnosis of neurodegenerative diseases and in treatment trials.

Extra-motor abnormalities in amyotrophic lateral sclerosis: another layer of heterogeneity

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease defined by the presence of muscle weakness. The motor features of disease are heterogeneous in site of onset and progression. There are also extra-motor features in some patients. The genetic basis for extra-motor features is uncertain. The heterogeneity of ALS is an issue for clinical trials. Areas covered: This paper reviews the range and prevalence of extra-motor features associated with ALS, and highlights the current information about genetic associations with extra-motor features. Expert commentary: There are extra-motor features of ALS, but these are not found in all patients. The most common is cognitive abnormality. More data is required to ascertain whether extra-motor features arise with progression of disease. Extra-motor features are reported in patients with a range of causative genetic mutations, but are not found in all patients with these mutations. Further studies are required of the heterogeneity of ALS, and genotype/phenotype correlations are required, taking note of extra-motor features.