Targeting the Complement-Sphingolipid System in COVID-19 and Gaucher Diseases: Evidence for a New Treatment Strategy

Inflammation in Fabry disease: stages, molecular pathways, and therapeutic implications

Fabry disease, a multisystem X-linked disorder caused by mutations in the alpha-galactosidase gene. This leads to the accumulation of globotriaosylceramide (Gb3) and globotriaosylsphingosine (Lyso-Gb3), culminating in various clinical signs and symptoms that significantly impact quality of life. Although treatments such as enzyme replacement, oral chaperone, and emerging therapies like gene therapy exist; delayed diagnosis often curtails their effectiveness. Our review highlights the importance of delineating the stages of inflammation in Fabry disease to enhance the timing and efficacy of diagnosis and interventions, particularly before the progression to fibrosis, where treatment options are less effective. Inflammation is emerging as an important aspect of the pathogenesis of Fabry disease. This is thought to be predominantly mediated by the innate immune response, with growing evidence pointing towards the potential involvement of adaptive immune mechanisms that remain poorly understood. Highlighted by the fact that Fabry disease shares immune profiles with systemic autoinflammatory diseases, blurring the distinctions between these disorders and highlighting the need for a nuanced understanding of immune dynamics. This insight is crucial for developing targeted therapies and improving the administration of current treatments like enzyme replacement. Moreover, our review discusses the complex interplay between these inflammatory processes and current treatments, such as the challenges posed by anti-drug antibodies. These antibodies can attenuate the effectiveness of therapies, necessitating more refined approaches to mitigate their impact. By advancing our understanding of the molecular changes, inflammatory mediators and causative factors that drive inflammation in Fabry disease, we aim to clarify their role in the disease's progression. This improved understanding will help us see how these processes fit into the current landscape of Fabry disease. Additionally, it will guide the development of more effective diagnostic and therapeutic approaches, ultimately improving patient care.

Cerebrospinal fluid metabolomic and proteomic characterization of neurologic post-acute sequelae of SARS-CoV-2 infection

The mechanism by which SARS-CoV-2 causes neurological post-acute sequelae of SARS-CoV-2 (neuro-PASC) remains unclear. Herein, we conducted proteomic and metabolomic analyses of cerebrospinal fluid (CSF) samples from 21 neuro-PASC patients, 45 healthy volunteers, and 26 inflammatory neurological diseases patients. Our data showed 69 differentially expressed metabolites and six differentially expressed proteins between neuro-PASC patients and healthy individuals. Elevated sphinganine and ST1A1, sphingolipid metabolism disorder, and attenuated inflammatory responses may contribute to the occurrence of neuro-PASC, whereas decreased levels of 7,8-dihydropterin and activation of steroid hormone biosynthesis may play a role in the repair process. Additionally, a biomarker cohort consisting of sphinganine, 7,8-dihydroneopterin, and ST1A1 was preliminarily demonstrated to have high value in diagnosing neuro-PASC. In summary, our study represents the first attempt to integrate the diagnostic benefits of CSF with the methodological advantages of multi-omics, thereby offering valuable insights into the pathogenesis of neuro-PASC and facilitating the work of neuroscientists in disclosing different neurological dimensions associated with COVID-19.

The metaproteome of the gut microbiota in pediatric patients affected by COVID-19

Introduction

The gut microbiota (GM) play a significant role in the infectivity and severity of COVID-19 infection. However, the available literature primarily focuses on adult patients and it is known that the microbiota undergoes changes throughout the lifespan, with significant alterations occurring during infancy and subsequently stabilizing during adulthood. Moreover, children have exhibited milder symptoms of COVID-19 disease, which has been associated with the abundance of certain protective bacteria. Here, we examine the metaproteome of pediatric patients to uncover the biological mechanisms that underlie this protective effect of the GM.

Methods

We performed nanoliquid chromatography coupled with tandem mass spectrometry on a high resolution analytical platform, resulting in label free quantification of bacterial protein groups (PGs), along with functional annotations via COG and KEGG databases by MetaLab-MAG. Additionally, taxonomic assignment was possible through the use of the lowest common ancestor algorithm provided by Unipept software.

Results

A COVID-19 GM functional dissimilarity respect to healthy subjects was identified by univariate analysis. The alteration in COVID-19 GM function is primarily based on bacterial pathways that predominantly involve metabolic processes, such as those related to tryptophan, butanoate, fatty acid, and bile acid biosynthesis, as well as antibiotic resistance and virulence.

Discussion

These findings highlight the mechanisms by which the pediatric GM could contribute to protection against the more severe manifestations of the disease in children. Uncovering these mechanisms can, therefore, have important implications in the discovery of novel adjuvant therapies for severe COVID-19.

COVID-19 and neurological disorders: what might connect Parkinson's disease to SARS-CoV-2 infection

SARS-CoV-2 infection leading to Coronavirus disease 19 (COVID-19) rapidly became a worldwide health emergency due to its elevated infecting capacity, morbidity, and mortality. Parkinson’s disease (PD) is the second most common neurodegenerative disorder and, nowadays the relationship between SARS-CoV-2 outbreak and PD reached a great interest. Apparently independent one from the other, both diseases share some pathogenetic and clinical features. The relationship between SARS-CoV-2 infection and PD is complex and it depends on the direction of the association that is which of the two diseases comes first. Some evidence suggests that SARS-CoV-2 infection might be a possible risk factor for PD wherein the exposure to SARS-CoV-2 increase the risk for PD. This perspective comes out from the increasing cases of parkinsonism following COVID-19 and also from the anatomical structures affected in both COVID-19 and early PD such as olfactory bulb and gastrointestinal tract resulting in the same symptoms such as hyposmia and constipation. Furthermore, there are many reported cases of patients who developed hypokinetic extrapyramidal syndrome following SARS-CoV-2 infection although these would resemble a post-encephalitic conditions and there are to date relevant data to support the hypothesis that SARS-CoV-2 infection is a risk factor for the development of PD. Future large, longitudinal and population-based studies are needed to better assess whether the risk of developing PD after COVID-19 exists given the short time span from the starting of pandemic. Indeed, this brief time-window does not allow the precise estimation of the incidence and prevalence of PD after pandemic when compared with pre-pandemic era. If the association between SARS-CoV-2 infection and PD pathogenesis is actually putative, on the other hand, vulnerable PD patients may have a greater risk to develop COVID-19 being also more prone to develop a more aggressive disease course. Furthermore, PD patients with PD showed a worsening of motor and non-motor symptoms during COVID-19 outbreak due to both infection and social restriction. As well, the worries related to the risk of being infected should not be neglected. Here we summarize the current knowledge emerging about the epidemiological, pathogenetic and clinical relationship between SARS-CoV-2 infection and PD.

The anaphylatoxin C5a: Structure, function, signaling, physiology, disease, and therapeutics

The complement system is one of the oldest known tightly regulated host defense systems evolved for efficiently functioning cell-based immune systems and antibodies. Essentially, the complement system acts as a pivot between the innate and adaptive arms of the immune system. The complement system collectively represents a cocktail of ∼50 cell-bound/soluble glycoproteins directly involved in controlling infection and inflammation. Activation of the complement cascade generates complement fragments like C3a, C4a, and C5a as anaphylatoxins. C5a is the most potent proinflammatory anaphylatoxin, which is involved in inflammatory signaling in a myriad of tissues. This review provides a comprehensive overview of human C5a in the context of its structure and signaling under several pathophysiological conditions, including the current and future therapeutic applications targeting C5a.

Exploring Pro-Inflammatory Immunological Mediators: Unraveling the Mechanisms of Neuroinflammation in Lysosomal Storage Diseases

Lysosomal storage diseases are a group of rare and ultra-rare genetic disorders caused by defects in specific genes that result in the accumulation of toxic substances in the lysosome. This excess accumulation of such cellular materials stimulates the activation of immune and neurological cells, leading to neuroinflammation and neurodegeneration in the central and peripheral nervous systems. Examples of lysosomal storage diseases include Gaucher, Fabry, Tay–Sachs, Sandhoff, and Wolman diseases. These diseases are characterized by the accumulation of various substrates, such as glucosylceramide, globotriaosylceramide, ganglioside GM2, sphingomyelin, ceramide, and triglycerides, in the affected cells. The resulting pro-inflammatory environment leads to the generation of pro-inflammatory cytokines, chemokines, growth factors, and several components of complement cascades, which contribute to the progressive neurodegeneration seen in these diseases. In this study, we provide an overview of the genetic defects associated with lysosomal storage diseases and their impact on the induction of neuro-immune inflammation. By understanding the underlying mechanisms behind these diseases, we aim to provide new insights into potential biomarkers and therapeutic targets for monitoring and managing the severity of these diseases. In conclusion, lysosomal storage diseases present a complex challenge for patients and clinicians, but this study offers a comprehensive overview of the impact of these diseases on the central and peripheral nervous systems and provides a foundation for further research into potential treatments.

Immunity of turbot Induced by inactivated vaccine of Aeromonas salmonicida from the perspective of DNA methylation

Introduction

DNA methylation was one of the most important modification in epigenetics and played an important role in immune response. Since the introduction of Scophthalmus maximus, the scale of breeding has continued to expand, during which diseases caused by various bacteria, viruses and parasites have become increasingly serious. Therefore, the inactivated vaccines have been widely researched and used in the field of aquatic products with its unique advantages. However, the immune mechanism that occurred in turbot after immunization with inactivated vaccine of Aeromonas salmonicida was not clear.

Methods

In this study, differentially methylated regions (DMRs) were screened by Whole Genome Bisulfite Sequencing (WGBS) and significantly differentially expressed genes (DEGs) were screened by Transcriptome sequencing. Double luciferase report assay and DNA pull-down assay were further verified the DNA methylation state of the gene promoter region affected genes transcriptional activity after immunization with inactivated vaccine of Aeromonas salmonicida.

Results

A total of 8149 differentially methylated regions (DMRs) were screened, in which there were many immune-related genes with altered DNA methylation status. Meanwhile, 386 significantly differentially expressed genes (DEGs) were identified, many of which were significantly enriched in Toll-like receptor signaling pathway, NOD-like receptor signaling pathway and C-type lectin receptor signaling pathway. Combined analysis of WGBS results and RNA-seq results, a total of 9 DMRs of negatively regulated genes are located in the promoter region, including 2 hypermethylated genes with lower expression and 7 hypomethylated genes with higher expression. Then, two immune-related genes C5a anaphylatoxin chemotactic receptor 1-like (C5ar1-Like) and Eosinophil peroxidase-like (EPX-Like), were screened to explore the regulation mechanism of DNA methylation modification on their expression level. Moreover, the DNA methylation state of the gene promoter region affected genes transcriptional activity by inhibiting the binding of transcription factors, which lead to changes in the expression level of the gene.

Discussion

We jointly analyzed WGBS and RNA-seq results and revealed the immune mechanism that occurred in turbot after immunized with inactivated vaccine of A. salmonicida from the perspective of DNA methylation.