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Gaucher disease (GD) is a lysosomal storage disorder (LSD) resulting from inherited glucocerebrosidase (GBA1) deficiency. GD diagnosis relies on GBA1 activity assays, typically employing 4-methylumbelliferyl-β-D-glucopyranoside (4MU-β-Glc) as fluorogenic substrate. However, these assays suffer from background 4MU release by the non-lysosomal GBA2 and cytosolic GBA3 enzymes. Here we developed GBA1-selective fluorogenic substrates by synthesizing a series of 6-O-acyl-4MU-β-Glc substrates with diverse fatty acid tails. Because of the chemical and enzymatic instability of the ester bonds, analogs of 6-O-palmitoyl-4MU-β-Glc (3) with different chemical linkages were synthesized. 6-O-alkyl-4MU-β-Glc 9, featuring an ether linkage, emerged as the most optimal GBA1 substrate, exhibiting both a low Km and compared to substrate 3 a high Vmax. Importantly, substrate 9 is not hydrolyzed by GBA2 and GBA3 and therefore acts as a superior substrate for GD diagnosis. Plants contain glycosyl phytosterols (campesterol, β-sitosterol, and sigmasterol) that may also be acylated at C-6. LC-MS/MS analysis revealed that 6-O-acylated and regular glycosylcholesterol (HexChol) tend to be increased in spleens of patients with GD. Moreover, significant increases in 6-O-acyl-glycosyl-phytosterols were detected in GD spleens. Our findings suggest uptake of (6-O-acyl)-glycosyl-phytosterols from plant food and subsequent lysosomal processing by GBA1, and comprise the first example of accumulation of an exogenous class of glycolipids in GD. Excessive exposure of rodents to glycosylated phytosterols has been reported to induce manifestations of Parkinson’s disease (PD). Further investigation is warranted to determine whether (6-O-acyl)-glycosyl-phytosterols could contribute to the enigmatic link between inherited defects in GBA1 and the risk for PD.

ABSTRACT Parascedosporium putredinis NO1 is a plant biomass-degrading ascomycete with a propensity to target the most recalcitrant components of lignocellulose. Here we applied proteomics and activity-based protein profiling (ABPP) to investigate the ability of P. putredinis NO1 to tailor its secretome for growth on different lignocellulosic substrates. Proteomic analysis of soluble and insoluble culture fractions following the growth of P. putredinis NO1 on six lignocellulosic substrates highlights the adaptability of the response of the P. putredinis NO1 secretome to different substrates. Differences in protein abundance profiles were maintained and observed across substrates after bioinformatic filtering of the data to remove intracellular protein contamination to identify the components of the secretome more accurately. These differences across substrates extended to carbohydrate-active enzymes (CAZymes) at both class and family levels. Investigation of abundant activities in the secretomes for each substrate revealed similar variation but also a high abundance of “unknown” proteins in all conditions investigated. Fluorescence-based and chemical proteomic ABPP of secreted cellulases, xylanases, and β-glucosidases applied to secretomes from multiple growth substrates for the first time confirmed highly adaptive time- and substrate-dependent glycoside hydrolase production by this fungus. P. putredinis NO1 is a promising new candidate for the identification of enzymes suited to the degradation of recalcitrant lignocellulosic feedstocks. The investigation of proteomes from the biomass bound and culture supernatant fractions provides a more complete picture of a fungal lignocellulose-degrading response. An in-depth understanding of this varied response will enhance efforts toward the development of tailored enzyme systems for use in biorefining.IMPORTANCEThe ability of the lignocellulose-degrading fungus Parascedosporium putredinis NO1 to tailor its secreted enzymes to different sources of plant biomass was revealed here. Through a combination of proteomic, bioinformatic, and fluorescent labeling techniques, remarkable variation was demonstrated in the secreted enzyme response for this ascomycete when grown on multiple lignocellulosic substrates. The maintenance of this variation over time when exploring hydrolytic polysaccharide-active enzymes through fluorescent labeling, suggests that this variation results from an actively tailored secretome response based on substrate. Understanding the tailored secretomes of wood-degrading fungi, especially from underexplored and poorly represented families, will be important for the development of effective substrate-tailored treatments for the conversion and valorization of lignocellulose.

This research investigates the relationship between the returns of selected Indonesian and US stock market indexes and their risks so as to guide new investors on how to choose their investments wisely. A quantitative descriptive method was used using performance data from three Indonesian and three US stock indexes over ten years to calculate an average return. The Sharpe Index was used to measure each index's risk. The results show that the average stock return for each index in the US is higher than the Indonesia indexes, while the level of risk in the US, on average, is lower. Investors are advised to invest in index categories with higher returns and low risk to increase the chance of gaining better returns while managing their risk to be as low as possible.

The human Golgi α-mannosidase, hGMII, removes two mannose residues from GlcNAc-Man5GlcNAc2 to produce GlcNAcMan3GlcNAc2, the precursor of all complex N-glycans including tumour-associated ones. The natural product GMII inhibitor, swainsonine, blocks processing of cancer-associated N-glycans, but also inhibits the four other human α-mannosidases, rendering it unsuitable for clinical use. Our previous structure-guided screening of iminosugar pyrrolidine and piperidine fragments identified two micromolar hGMII inhibitors occupying the enzyme active pockets in adjacent, partially overlapping sites. Here we demonstrate that fusing these fragments yields swainsonine-configured indolizidines featuring a C3-substituent that act as selective hGMII inhibitors. Our structure-guided GMII-selective inhibitor design complements a recent combinatorial approach that yielded similarly configured and substituted indolizidine GMII inhibitors, and holds promise for the potential future development of anti-cancer agents targeting Golgi N-glycan processing. [ABSTRACT FROM AUTHOR]

Lysosomal degradation pathways coordinate the clearance of superfluous and damaged cellular components. Compromised lysosomal degradation is a hallmark of many degenerative diseases, including lysosomal storage diseases (LSDs), which are caused by loss-of-function mutations within both alleles of a lysosomal hydrolase, leading to lysosomal substrate accumulation. Gaucher's disease, characterized by <15% of normal glucocerebrosidase function, is the most common LSD and is a prominent risk factor for developing Parkinson's disease. Here, we show that either of two structurally distinct small molecules that modulate PIKfyve activity, identified in a high-throughput cellular lipid droplet clearance screen, can improve glucocerebrosidase function in Gaucher patient-derived fibroblasts through an MiT/TFE transcription factor that promotes lysosomal gene translation. An integrated stress response (ISR) antagonist used in combination with a PIKfyve modulator further improves cellular glucocerebrosidase activity, likely because ISR signaling appears to also be slightly activated by treatment by either small molecule at the higher doses employed. This strategy of combining a PIKfyve modulator with an ISR inhibitor improves mutant lysosomal hydrolase function in cellular models of additional LSD. [ABSTRACT FROM AUTHOR]

Local knowledge about natural resources is increasingly crucial in formulating conservation strategies and activities. This study collects data regarding medicinal plant use from Sepahat and Tamiang village residents. A total of 100 participants were included in the study, consisting of 50 participants from the Sepahat and another 50 from the Tamiang. Respondents were selected using the Snowball sampling technique, which involved identifying a key individual, such as local leaders, to initiate recruitment of other respondents. The study's findings indicate that the inhabitants of Sepahat village utilize 36 plant species belonging to 24 families, while Tamiang villagers use 11 plant species belonging to eight families. In Sepahat village, the botanical components used for medication comprise 25% rhizomes, 8% bark, 22% fruit, 3% shoots, 34% leaves, and 8% stems. In contrast, Tamiang comprises 23% rhizomes, 16% bark, 15% fruit, and 46% leaves. The utilization of stems and bark has the potential to pose a threat to sustainability. Among various uses, it has been observed that approximately 33% in Sepahat and 27% in Tamiang can lead to plant mortality. Conservation initiatives have been undertaken for 71% of Sepahat and 67% of the utilized plant species in Taminag. Traditional medicines have been used for generations to treat various health conditions, such as back pain, bleeding, controlling cholesterol, coughs, dengue fever, and diabetes. While current use might not threaten the biosphere reserve, villagers must embrace sustainable harvesting techniques, including selective harvesting, replanting, and establishing community nurseries dedicated to cultivating medicinal plants [ABSTRACT FROM AUTHOR]

The sulfolipid sulfoquinovosyl diacylglycerol (SQDG), produced by plants, algae, and cyanobacteria, constitutes a major sulfur reserve in the biosphere. Microbial breakdown of SQDG is critical for the biological utilization of its sulfur. This commences through release of the parent sugar, sulfoquinovose (SQ), catalyzed by sulfoquinovosidases (SQases). These vanguard enzymes are encoded in gene clusters that code for diverse SQ catabolic pathways. To identify, visualize and isolate glycoside hydrolase CAZY‐family 31 (GH31) SQases in complex biological environments, we introduce SQ cyclophellitol‐aziridine activity‐based probes (ABPs). These ABPs label the active site nucleophile of this enzyme family, consistent with specific recognition of the SQ cyclophellitol‐aziridine in the active site, as evidenced in the 3D structure of Bacillus megaterium SQase. A fluorescent Cy5‐probe enables visualization of SQases in crude cell lysates from bacteria harbouring different SQ breakdown pathways, whilst a biotin‐probe enables SQase capture and identification by proteomics. The Cy5‐probe facilitates monitoring of active SQase levels during different stages of bacterial growth which show great contrast to more traditional mRNA analysis obtained by RT‐qPCR. Given the importance of SQases in global sulfur cycling and in human microbiota, these SQase ABPs provide a new tool with which to study SQase occurrence, activity and stability. [ABSTRACT FROM AUTHOR]

Glycoside hydrolases (glycosidases) take part in myriad biological processes and are important therapeutic targets. Competitive and mechanism‐based inhibitors are useful tools to dissect their biological role and comprise a good starting point for drug discovery. The natural product, cyclophellitol, a mechanism‐based, covalent and irreversible retaining β‐glucosidase inhibitor has inspired the design of diverse α‐ and β‐glycosidase inhibitor and activity‐based probe scaffolds. Here, we sought to deepen our understanding of the structural and functional requirements of cyclophellitol‐type compounds for effective human α‐glucosidase inhibition. We synthesized a comprehensive set of α‐configured 1,2‐ and 1,5a‐cyclophellitol analogues bearing a variety of electrophilic traps. The inhibitory potency of these compounds was assessed towards both lysosomal and ER retaining α‐glucosidases. These studies revealed the 1,5a‐cyclophellitols to be the most potent retaining α‐glucosidase inhibitors, with the nature of the electrophile determining inhibitory mode of action (covalent or non‐covalent). DFT calculations support the ability of the 1,5a‐cyclophellitols, but not the 1,2‐congeners, to adopt conformations that mimic either the Michaelis complex or transition state of α‐glucosidases. [ABSTRACT FROM AUTHOR]

The transfer of an adenosine diphosphate (ADP) ribose moiety to a nucleophilic side chain by consumption of nicotinamide adenine dinucleotide is referred to as ADP‐ribosylation, which allows for the spatiotemporal regulation of vital processes such as apoptosis and DNA repair. Recent mass‐spectrometry based analyses of the "ADP‐ribosylome" have identified histidine as ADP‐ribose acceptor site. In order to study this modification, a fully synthetic strategy towards α‐configured N(τ)‐ and N(π)‐ADP‐ribosylated histidine‐containing peptides has been developed. Ribofuranosylated histidine building blocks were obtained via Mukaiyama‐type glycosylation and the building blocks were integrated into an ADP‐ribosylome derived peptide sequence using fluorenylmethyloxycarbonyl (Fmoc)‐based solid‐phase peptide synthesis. On‐resin installation of the ADP moiety was achieved using phosphoramidite chemistry, and global deprotection provided the desired ADP‐ribosylated oligopeptides. The stability under various chemical conditions and resistance against (ADP‐ribosyl) hydrolase‐mediated degradation has been investigated to reveal that the constructs are stable under various chemical conditions and non‐degradable by any of the known ADP‐ribosylhydrolases. [ABSTRACT FROM AUTHOR]

Cyclophellitol is a potent and selective mechanism‐based retaining β‐glucosidase inhibitor that has served as a versatile starting point for the development of activity‐based glycosidase probes (ABPs). We developed routes of synthesis of eight mono‐ and dideoxycyclophellitols and cyclophellitol aziridines, the latter as ABPs carrying either a biotin or fluorophore linked to the aziridine nitrogen. We reveal the potency of these 24 compounds as inhibitors of the three human retaining β‐glucosidases, GBA1, GBA2 and GBA3. We show that 3,6‐dideoxy‐β‐galacto‐cyclophellitol aziridine selectively captures GBA3 over GBA1 and GBA2 in extracts of cells overexpressing both GBA2 and GBA3. We also identify a probe that selectively labels GBA1 and GBA2 over GBA3 at lower concentrations. In sum, the here‐presented studies reveal new chemistries to prepare chiral, substituted cyclitol epoxides and aziridines, add to the growing suite of cyclophellitols varying in configuration and substitution pattern, and yielded a reagent that may find use to investigate the physiological role and therapeutic relevance of the most elusive of the three retaining β‐glucosidases: GBA3. [ABSTRACT FROM AUTHOR]

CD74 is a cell-surface receptor for the cytokine macrophage migration inhibitory factor (MIF). MIF binding to CD74 induces a signaling cascade resulting in the release of its cytosolic intracellular domain (CD74-ICD), which regulates transcription in naïve B and chronic lymphocytic leukemia (CLL) cells. In the current study, we investigated the role of CD74 in the regulation of the immunosuppressive tumor microenvironment (TME) in triple-negative breast cancer (TNBC). TNBC is the most aggressive breast cancer subtype and is characterized by massive infiltration of immune cells to the tumor microenvironment, making this tumor a good candidate for immunotherapy. The tumor and immune cells in TNBC express high levels of CD74; however, the function of this receptor in the tumor environment has not been extensively characterized. Regulatory B cells (Bregs) and tolerogenic dendritic cells) tol-DCs (were previously shown to attenuate the antitumor immune response in TNBC. Here, we demonstrate that CD74 enhances tumor growth by inducing the expansion of tumor-infiltrating tol-DCs and Bregs. Utilizing CD74-KO mice, Cre-flox mice lacking CD74 in CD23+ mature B cells, mice lacking CD74 in the CD11c+ population, and a CD74 inhibitor (DRQ), we elucidate the mechanism by which CD74 inhibits antitumor immunity. MIF secreted from the tumor cells activates CD74 expressed on DCs. This activation induces the binding of CD74-ICD to the SP1 promotor, resulting in the up-regulation of SP1 expression. SP1 binds the IL-1β promotor, leading to the down-regulation of its transcription. The reduced levels of IL-1β lead to decreased antitumor activity by allowing expansion of the tol-DC, which induces the expansion of the Breg population, supporting the cross-talk between these 2 populations. Taken together, these results suggest that CD74+ CD11c+ DCs are the dominant cell type involved in the regulation of TNBC progression. These findings indicate that CD74 might serve as a novel therapeutic target in TNBC., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: AAV, RM-R and OHSU have a significant financial interest in Artielle ImmunoTherapeutics, Inc., a company that may have a commercial interest in the results of this research and technology. This potential conflict of interest has been reviewed and managed by the OHSU and VA Portland Health Care System Conflict of Interest in Research Committees., (Copyright: © 2024 Pellegrino et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype. The tumor microenvironment (TME) plays a major regulatory role in TNBC progression and is highly infiltrated by suppressive immune cells that reduce anti-tumor immune activity. Although regulatory B cells (Bregs) are a key TME component, knowledge of their function in TNBC is limited. CD84 is a homophilic adhesion molecule that promotes the survival of blood tumors. In the current study, we followed the role of CD84 in the regulation of the TME in TNBC. We demonstrate that CD84 induces a cascade in Bregs that involves the β-catenin and Tcf4 pathway, which induces the transcription of interleukin-10 by binding to its promoter and the promoter of its regulator, AhR. This leads to the expansion of Bregs, which in turn control the activity of other immune cells and immune suppression. Accordingly, we suggest CD84 as a therapeutic target for breaking immune tolerance in TNBC., Competing Interests: Declaration of interests S.T.R. and I.S. have stock options as founders in SLAMBio. This potential conflict of interest has been reviewed and managed by the Weizmann and COH Conflict of Interest in Research Committees., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Neonatal iron deficiency anemia is prevalent among domestic pigs but does not occur in the offspring of wild boar. The main causes of this disorder in piglets of modern pig breeds are paucity of hepatic iron stores, high birth weight, and rapid growth. Replenishment of fetal iron stores is a direct result of iron transfer efficiency across the placenta. In this study, we attempted to investigate the molecular potential of iron transfer across the placenta as a possible cause of differences between wild boar and Polish Large White (PLW) offspring. Furthermore, by analyzing placentas from PLW gilts that had litters of different sizes, we aimed to elucidate the impact of the number of fetuses on placental ability to transport iron. Using RNA sequencing, we examined the expression of iron-related genes in the placentas from wild boar and PLW gilts. We did not reveal significant differences in the expression of major iron transporters among all analyzed placentas. However, in wild boar placentas, we found higher expression of copper-dependent ferroxidases such as ceruloplasmin, zyklopen, and hephaestin, which facilitate iron export to the fetal circulation. We also determined a close co-localization of ceruloplasmin and zyklopen with ferroportin, the only iron exporter.

Interdisciplinary Emergency Department/hospital-based teams represent a promising care model to improve identification of and intervention for elder mistreatment. Two institutions, Weill Cornell Medicine/NewYork-Presbyterian Hospital and the University of Colorado Anschutz Medical Campus have launched such programs and are exploring multiple strategies for effective dissemination. These strategies include: (1) program evaluation research, (2) framing as a new model of geriatric care, (3) understanding the existing incentives of health systems, EDs, and hospitals to align with them, (4) connecting to ongoing ED/hospital initiatives, (5) identifying and collaborating with communities with strong elder mistreatment response that want to integrate the ED/hospital, (6) developing and making easily accessible high-quality, comprehensive protocols and training materials, (7) offering technical assistance and support, (8) communications outreach to raise awareness, and (9) using an existing framework to inform implementation in new hospitals and health systems.

The emergency department and hospital provide a unique and important opportunity to identify elder mistreatment and offer intervention. To help manage these complex cases, multi-disciplinary response teams have been launched. In developing these teams, it quickly became clear that social workers play a critical role in responding to elder mistreatment. Their unique skillset allows them to establish close connections with community resources, collaborate with various hospital stakeholders, support patients/families/caregivers through challenging situations, navigate the legal and protective systems, and balance patient safety and quality of life in disposition decision-making. The role of the social worker on these multi-faceted teams includes conducting a comprehensive biopsychosocial assessment, helping to develop a safe discharge plan, and making appropriate referrals, among other responsibilities. Any institution considering developing a multi-disciplinary program should recognize the critical importance of social work.

Parascedosporium putredinis NO1 is a plant biomass-degrading ascomycete with a propensity to target the most recalcitrant components of lignocellulose. Here we applied proteomics and activity-based protein profiling (ABPP) to investigate the ability of P. putredinis NO1 to tailor its secretome for growth on different lignocellulosic substrates. Proteomic analysis of soluble and insoluble culture fractions following the growth of P. putredinis NO1 on six lignocellulosic substrates highlights the adaptability of the response of the P. putredinis NO1 secretome to different substrates. Differences in protein abundance profiles were maintained and observed across substrates after bioinformatic filtering of the data to remove intracellular protein contamination to identify the components of the secretome more accurately. These differences across substrates extended to carbohydrate-active enzymes (CAZymes) at both class and family levels. Investigation of abundant activities in the secretomes for each substrate revealed similar variation but also a high abundance of "unknown" proteins in all conditions investigated. Fluorescence-based and chemical proteomic ABPP of secreted cellulases, xylanases, and β-glucosidases applied to secretomes from multiple growth substrates for the first time confirmed highly adaptive time- and substrate-dependent glycoside hydrolase production by this fungus. P. putredinis NO1 is a promising new candidate for the identification of enzymes suited to the degradation of recalcitrant lignocellulosic feedstocks. The investigation of proteomes from the biomass bound and culture supernatant fractions provides a more complete picture of a fungal lignocellulose-degrading response. An in-depth understanding of this varied response will enhance efforts toward the development of tailored enzyme systems for use in biorefining.IMPORTANCEThe ability of the lignocellulose-degrading fungus Parascedosporium putredinis NO1 to tailor its secreted enzymes to different sources of plant biomass was revealed here. Through a combination of proteomic, bioinformatic, and fluorescent labeling techniques, remarkable variation was demonstrated in the secreted enzyme response for this ascomycete when grown on multiple lignocellulosic substrates. The maintenance of this variation over time when exploring hydrolytic polysaccharide-active enzymes through fluorescent labeling, suggests that this variation results from an actively tailored secretome response based on substrate. Understanding the tailored secretomes of wood-degrading fungi, especially from underexplored and poorly represented families, will be important for the development of effective substrate-tailored treatments for the conversion and valorization of lignocellulose., Competing Interests: The authors declare no conflict of interest.

Purpose: Communication failure is one of the most significant causes of medical errors. Providing care to patients with seizures at comprehensive epilepsy centers requires uninterrupted coverage and a multidisciplinary approach. However, handoff practices in these settings have not been comprehensively assessed, and recommendations for their standardization are currently lacking. The aim of this observational study was to define the scope of existing practices for patient handoffs across epilepsy centers in the United States and provide relevant recommendations., Methods: A 79-question survey was developed to establish the patterns of transition of care for patients undergoing continuous EEG recording, including the periodicity of handoffs and specifics of the relevant workflow. With permission from the National Association of Epilepsy Centers (NAEC), the survey was distributed to the medical directors of all Level 3 and 4 NAEC-accredited epilepsy centers in the United States., Results: The responses were obtained from 70 institutions yielding a survey response rate of 26%. Of these, more than 77% had established weekly handoff processes for both the epilepsy monitoring unit and continuous EEG (cEEG) monitoring services. However, only 53% and 43% of centers had procedures for daily service transfers for the patients admitted to the epilepsy monitoring unit or the patients undergoing cEEG, respectively. The patterns of handoffs were complex and utilized group handoffs in < 50% of institutions. In most centers (>70%), patient data transmitted through handoffs included history, clinical information, and EEG findings. However, templates were not applied to standardize this information. All participants agreed or strongly agreed that a culture of patient safety was maintained in their place of practice; however, 12% of participants felt that insufficient time was allowed to discuss these patients or carry out the handoffs without interruptions., Conclusions: Existing handoff practices are not uniform or fully established across epilepsy centers in the United States. This study recommends that guidelines for formal handoff procedures be developed and introduced as a quality metric for all NAEC-accredited epilepsy centers., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2024 by the American Clinical Neurophysiology Society.)

Background: In Australia the incidence of HIV has declined steadily, yet sustained reduction of HIV transmission in this setting requires improved public health responses. As enhanced public health responses and prioritisation of resources may be guided by molecular epidemiological data, here we aimed to assess the applicability of these approaches in Victoria, Australia., Methods: A comprehensive collection of HIV-1 pol sequences from individuals diagnosed with HIV in Victoria, Australia, between January 1st 2000 and December 31st 2020 were deidentified and used as the basis of our assessment. These sequences were subtyped and surveillance drug resistance mutations (SDRMs) identified, before definition of transmission groups was performed using HIV-TRACE (0.4.4). Phylodynamic methods were applied using BEAST (2.6.6), assessing effective reproductive numbers for large groups, and additional demographic data were integrated to provide a high resolution view of HIV transmission in Victoria on a decadal time scale., Findings: Based on standard settings for HIV-TRACE, 70% (2438/3507) of analysed HIV-1 pol sequences were readily assigned to a transmission group. Individuals in transmission groups were more commonly males (aOR 1.50), those born in Australia (aOR 2.13), those with probable place of acquisition as Victoria (aOR 6.73), and/or those reporting injectable drug use (aOR 2.13). SDRMs were identified in 375 patients (10.7%), with sustained transmission of these limited to a subset of smaller groups. Informative patterns of epidemic growth, stabilisation, and decline were observed; many transmission groups showed effective reproductive numbers ( R e ) values reaching greater than 4.0, representing considerable epidemic growth, while others maintained low R e values., Interpretation: This study provides a high resolution view of HIV transmission in Victoria, Australia, and highlights the potential of molecular epidemiology to guide and enhance public health responses in this setting. This informs ongoing discussions with community groups on the acceptability and place of molecular epidemiological approaches in Australia., Funding: National Health and Medical Research Council, Australian Research Council., Competing Interests: Professor Sharon Lewin has received consulting fees from Abivax, Geovax, ViiV, Tetralogic, Vaxxinity, and Esfam, as well as honoraria from Gilead and Merck Sharpe & Dohme (Merck). The Victorian Department of Health co-funded this research and were involved project conception and data acquisition, although was not involved in the analysis or interpretation of results for this work. The authors declare no other conflicts., (© 2024 The Author(s).)

Glycoside hydrolases (glycosidases) take part in myriad biological processes and are important therapeutic targets. Competitive and mechanism-based inhibitors are useful tools to dissect their biological role and comprise a good starting point for drug discovery. The natural product, cyclophellitol, a mechanism-based, covalent and irreversible retaining β-glucosidase inhibitor has inspired the design of diverse α- and β-glycosidase inhibitor and activity-based probe scaffolds. Here, we sought to deepen our understanding of the structural and functional requirements of cyclophellitol-type compounds for effective human α-glucosidase inhibition. We synthesized a comprehensive set of α-configured 1,2- and 1,5a-cyclophellitol analogues bearing a variety of electrophilic traps. The inhibitory potency of these compounds was assessed towards both lysosomal and ER retaining α-glucosidases. These studies revealed the 1,5a-cyclophellitols to be the most potent retaining α-glucosidase inhibitors, with the nature of the electrophile determining inhibitory mode of action (covalent or non-covalent). DFT calculations support the ability of the 1,5a-cyclophellitols, but not the 1,2-congeners, to adopt conformations that mimic either the Michaelis complex or transition state of α-glucosidases., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Structural maintenance of chromosomes flexible hinge domain-containing 1 (SMCHD1) is a noncanonical SMC protein and an epigenetic regulator. Mutations in SMCHD1 cause facioscapulohumeral muscular dystrophy (FSHD), by overexpressing DUX4 in muscle cells. Here, we demonstrate that SMCHD1 is a key regulator of alternative splicing in various cell types. We show how SMCHD1 loss causes splicing alterations of DNMT3B, which can lead to hypomethylation and DUX4 overexpression. Analyzing RNA sequencing data from muscle biopsies of patients with FSHD and Smchd1 knocked out cells, we found mis-splicing of hundreds of genes upon SMCHD1 loss. We conducted a high-throughput screen of splicing factors, revealing the involvement of the splicing factor RBM5 in the mis-splicing of DNMT3B. Subsequent RNA immunoprecipitation experiments confirmed that SMCHD1 is required for RBM5 recruitment. Last, we show that mis-splicing of DNMT3B leads to hypomethylation of the D4Z4 region and to DUX4 overexpression. These results suggest that DNMT3B mis-splicing due to SMCHD1 loss plays a major role in FSHD pathogenesis.

Disruptions in spatiotemporal gene expression can result in atypical brain function. Specifically, autism spectrum disorder (ASD) is characterized by abnormalities in pre-mRNA splicing. Abnormal splicing patterns have been identified in the brains of individuals with ASD, and mutations in splicing factors have been found to contribute to neurodevelopmental delays associated with ASD. Here we review studies that shed light on the importance of splicing observed in ASD and that explored the intricate relationship between splicing factors and ASD, revealing how disruptions in pre-mRNA splicing may underlie ASD pathogenesis. We provide an overview of the research regarding all splicing factors associated with ASD and place a special emphasis on five specific splicing factors-HNRNPH2, NOVA2, WBP4, SRRM2, and RBFOX1-known to impact the splicing of ASD-related genes. In the discussion of the molecular mechanisms influenced by these splicing factors, we lay the groundwork for a deeper understanding of ASD's complex etiology. Finally, we discuss the potential benefit of unraveling the connection between splicing and ASD for the development of more precise diagnostic tools and targeted therapeutic interventions. This article is categorized under: RNA in Disease and Development > RNA in Disease RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution RNA Evolution and Genomics > Computational Analyses of RNA RNA-Based Catalysis > RNA Catalysis in Splicing and Translation., (© 2024 The Authors. WIREs RNA published by Wiley Periodicals LLC.)

Competing Interests: The authors have no funding or conflicts of interest to disclose.

Objective: Patients with functional neurological disorder involving the motor system (eg, functional weakness, functional gait) may acutely present to the hospital for new-onset symptoms. For some, symptoms may remain severe enough at the time of hospital discharge to qualify for an inpatient rehabilitation facility stay., Design: Data were extracted via retrospective chart review on functional neurological disorder patients ( N = 22) admitted to an inpatient rehabilitation facility between September 2019 and May 2022. Demographic and clinical data, including admission and discharge physical and occupational therapy measurements on the Inpatient Rehabilitation Facility Patient Assessment Instrument, were recorded and analyzed., Results: Symptom duration was less than 1 wk for nearly two thirds of the cohort. After an approximately 2-wk length of stay, patients showed statistically significant changes in admission to discharge measures of self-care, transfers, ambulation, and balance. More than 95% of patients were able to be discharged home. The presence or absence of comorbid depression, anxiety, or posttraumatic stress disorder did not impact outcomes., Conclusions: For a subset of patients with persistent motor symptoms after an acute hospital admission for a new diagnosis of functional neurological disorder, a relatively short inpatient rehabilitation facility stay was associated with significant clinical gains., Competing Interests: Financial disclosure statements have been obtained, and no conflicts of interest have been reported by the authors or by any individuals in control of the content of this article., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Lead (Pb) has become a major environmental contaminant. There are several ways in which lead can enter the human body and cause toxic effects on human health. This review focuses on the impact of lead toxicity at prenatal and early life stages and its effect on neurodevelopment. Lead exposure to the developing foetus targets foetal neural stem cells. Hence, it has detrimental effects on developing neural and glial cells, adversely influencing cognition and behaviour. Lead has a profound influence on the movement of calcium ions (Ca 2+ ), which can be attributed to most of the mechanisms by which lead affects neurodevelopment. There is no known safe threshold of lead exposure for children. Lead can affect foetal neurodevelopment leading to various neurological disorders, and neurotoxic effects on behavioural and cognitive outcomes. In this review, we discuss prenatal and early-life lead exposure, its mechanism, and consequences for neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease in later stages of life. This review further highlights the importance of lead exposure during pregnancy and lactation periods as well as early development of the child in understanding the extent of lead-induced neurological damage to the foetus/children and the associated future risks., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.