Pathogenic Role Research Articles

Editorial: The roles of pathogens in gut-related diseases and the strategies for inhibiting their growth

Editorial: The roles of pathogens in gut-related diseases and the strategies for inhibiting their growth

Investigation of choline-binding protein of CbpD in the pathogenesis of Streptococcus suis type 2

Streptococcus suis serotype 2 (S. suis type 2, SS2) is one of the zoonotic pathogens known to induce meningitis, septicemia, and arthritis in both pigs and humans, resulting in public health concerns. CbpD, also termed CrfP, is one of the choline-binding proteins (CBPs) that was found as a murein hydrolase in SS2 and plays crucial roles in natural genetic transformation under the control of ComRS-ComX regulatory system by a previous study. Nonetheless, the possible functions of CbpD in virulence and pathogenesis in SS2 remain unclear. In this study, a cbpD gene mutant (ΔcbpD) with its complemental strain (cΔcbpD) was constructed and further used to examine the pathogenic roles of CbpD in SS2 infection. The results showed that the CbpD deficiency leads to increased bacterial chain elongation and aggregation with little impact on the growth capability of SS2. The ΔcbpD strain represented more vulnerable to a thermo, acid, or oxidative stress. Elevated adhesion to human epithelial HEp-2 cells, decreased invasion into bEND3.0 cells, and more easily phagocytosed by murine RAW264.7 macrophages of ΔcbpD were found. The virulence of cbpD mutant was attenuated in a mouse infection model. Enhanced susceptibility within mice blood and impaired ability to colonize organs with alleviated histopathological lesions were also demonstrated as compared with wild-type SS2. It is noteworthy that the discrepant expression of multiple virulence-associated factors including serine/threonine phosphorylase Stp, anti-phagocytosis factor of transglutaminase TGase and adhesin of chaperon DnaJ, were examined resulting from the deletion of cbpD. Overall, these findings provided evidence that the CbpD factor contributes to SS2 infection and is involved in bacterial adhesion, invasion, and anti-phagocytosis processes by modulating crucial virulence-associated factors expression.

Emerging concepts and treatments in autoinflammatory interferonopathies and monogenic systemic lupus erythematosus.

Over the past two decades, the number of genetically defined autoinflammatory interferonopathies has steadily increased. Aicardi-Goutières syndrome and proteasome-associated autoinflammatory syndromes (PRAAS, also known as CANDLE) are caused by genetic defects that impair homeostatic intracellular nucleic acid and protein processing respectively. Research into these genetic defects revealed intracellular sensors that activate type I interferon production. In SAVI and COPA syndrome, genetic defects that cause chronic activation of the dinucleotide sensor stimulator of interferon genes (STING) share features of lung inflammation and fibrosis; and selected mutations that amplify interferon-α/β receptor signalling cause central nervous system manifestations resembling Aicardi-Goutières syndrome. Research into the monogenic causes of childhood-onset systemic lupus erythematosus (SLE) demonstrates the pathogenic role of autoantibodies to particle-bound extracellular nucleic acids that distinguishes monogenic SLE from the autoinflammatory interferonopathies. This Review introduces a classification for autoinflammatory interferonopathies and discusses the divergent and shared pathomechanisms of interferon production and signalling in these diseases. Early success with drugs that block type I interferon signalling, new insights into the roles of cytoplasmic DNA or RNA sensors, pathways in type I interferon production and organ-specific pathology of the autoinflammatory interferonopathies and monogenic SLE, reveal novel drug targets that could personalize treatment approaches.

Inborn errors of immunity reveal the molecular requirements for the generation and maintenance of human IL-9 expressing cells.

CD4+ T cells play essential roles in adaptive immunity. Distinct CD4+ T cell subsets - Th1, Th2, Th17, Th22, T follicular helper and regulatory T cells - have been identified and their contributions to host defence and immune regulation are increasingly well-defined. IL-9 producing Th9 cells were first described in 2008 and appear to play both protective and pathogenic roles in human immunity. However, key requirements for generating human Th9 cells remain incompletely defined. Define signalling pathways that regulate IL-9 production by human CD4+ T cells. Human naive and memory CD4+ T cells were cultured under different conditions and the molecular mechanisms regulating IL-9 induction were determined by assessing the ability of CD4+ T cells from a broad range of patients (n=92) with pathogenic variants in key immune genes (n=21) to differentiate into IL-9+ cells. We identified two culture conditions that yielded IL-9-expressing cells from naïve CD4+ T cells, and amplified IL-9 production by in vivo-generated memory CD4+ T cells: TGFβ plus IL-4 (i.e. Th9 polarising condition), and the combination of IL-21, IL-23, IL-6, IL-1β and TGFβ (i.e. Th17 polarising condition). Combining these conditions had a synergistic effect in generating IL-9+CD4+ T cells. IL-9 induction required STAT3-activating cytokines as well as intact signalling via the TCR and STAT5. Importantly, IL-9 induction was restrained by IFNγ/STAT1 and IL-10. Our findings revealed critical molecules involved in inducing/restraining IL-9 production by human CD4+ T cells, thereby identifying pathways that could be targeted to modulate IL-9 in health and disease.

Proteomic Profile Regulated by the Immunomodulatory Jusvinza Drug in Neutrophils Isolated from Rheumatoid Arthritis Patients

Jusvinza is an immunomodulatory drug composed of an altered peptide ligand (APL) designed from a novel CD4+ T cell epitope of human heat shock protein 60 (HSP60), an autoantigen involved in the pathogenesis of rheumatoid arthritis (RA). The peptide induces regulatory T cells and decreases levels of TNF-α and IL-17; pre-clinical and phase I clinical studies support its use for the treatment of RA. This peptide was repositioned for the treatment of COVID-19 patients with signs of hyperinflammation. Neutrophils play a pathogenic role in both RA and severe forms of COVID-19. To add novel evidence about the mechanism of action of Jusvinza, the proteomic profile regulated by this peptide of neutrophils isolated from four RA patients was investigated using LC-MS/MS and bioinformatics analysis. A total of 149 proteins were found to be differentially modulated in neutrophils treated with Jusvinza. The proteomic profile regulated by Jusvinza is characterized by the presence of proteins related to RNA splicing, phagocytosis, endocytosis, and immune functions. In response to Jusvinza treatment, several proteins that regulate the NF-κB signaling pathway were differentially modulated, supporting the peptide’s anti-inflammatory effect. Proteins related to metabolic pathways that supply ATP for cellular functions or lipid metabolites with immunoregulatory properties were also identified. Additionally, several structural components of neutrophil extracellular traps (NETs) were decreased in Jusvinza-treated cells, supporting its impairment of this biological process. Of note, these findings were validated by in vitro experiments which confirmed that Jusvinza decreased NET formation. Such results provide evidence of the molecular mechanism of action and support the therapeutic potentialities of Jusvinza to treat other diseases characterized by hyperinflammation besides RA and COVID-19.

STING deficiency ameliorates mouse models of lupus and atherosclerosis.

Systemic lupus erythematosus (SLE) is a systemic autoimmune syndrome characterized by autoreactive responses to nucleic acids, dysregulation of the type I Interferon (IFN-I) pathway, and accelerated atherosclerosis. The stimulator of interferon genes (STING), a cytosolic DNA-sensor, has pathogenic implications in various inflammatory diseases. However, its specific role in SLE pathogenesis, particularly in tissue damage, remains unclear. This study aimed to elucidate the role of STING in murine models of TLR7-driven lupus and atherosclerosis. A TLR7-driven lupus model was induced using imiquimod (IMQ) in wild type (WT) and STING knockout (Sting1-/-) mice on a B6 background. Mice were assessed for organ involvement, serum autoantibodies, and innate and adaptive immune responses. Additionally, Sting1-/- mice were backcrossed to Apolipoprotein E knockout (Apoe-/-) mice, and both Apoe-/- and Apoe-/-Sting1-/- mice were fed a high-fat chow (HFC) diet to induce atherosclerosis. Phenotypic assessments were conducted. Compared to IMQ-treated WT mice, Sting1-/- mice exhibited reduced disease severity in the lupus-like phenotype, characterized by decreased splenomegaly, lower renal immune complex deposition and renal damage, diminished expansion of myeloid cells, and reduced activation of T and B lymphocytes. IMQ-induced DNA release associated with IFN-β production and subsequent IFN-induced responses were attenuated in Sting1-/- mice. DNase I treatment mitigated IMQ-induced pro-inflammatory responses in WT mice but had no effect in Sting1-/- mice. Furthermore, STING deficiency conferred protection against vascular damage and reduced atherosclerosis burden, accompanied by decreased IFN-I production. Human monocyte-derived macrophages treated with IFN-I significantly internalized more acetylated LDL when compared to untreated cells, while an association between oxidized nucleic acids and disease activity and vascular damage was found in human SLE. These findings highlight a pathogenic role of STING and downstream IFN responses in TLR7-driven autoimmunity, vascular damage and atherosclerosis, supporting a therapeutic potential for STING inhibition in SLE treatment. Further research is warranted to elucidate the mechanisms underlying STING's involvement in these processes and to explore the feasibility of targeting STING as a therapeutic strategy in SLE and related autoimmune disorders.

Chronic Nf-κB Inhibition Prevents Experimental Aging Nephropathy.

Introduction The pathogenesis of aging nephropathy is yet to be elucidated. Intrarenal Angiotensin-II (AngII) and activation of the NF-κB and NLRP3 inflammasome pathways exert a relevant pathogenic role in the progression of chronic kidney disease (CKD). We sought to investigate whether monotherapy with Losartan and combined treatment with Losartan and the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) would attenuate experimental aging nephropathy. Materials and Methods Forty adult Male Munich-Wistar rats were distributed among four groups: 12M (n=10), untreated 12-month-old rats; 15M (n=10), untreated 15-month-old rats; 15MLos (n=8), rats receiving Losartan (50 mg/kg/d) and 15MLos+PDTC (n=8), rats receiving Losartan and PDTC (60 mg/kg/d). All treatments were given by mouth from 12 to 15 months of age. Results Group 15M exhibited slightly decreased tail-cuff pressure, and marked increase in albuminuria, sclerotic glomeruli, cortical collagen-1 deposition and infiltration by myofibroblasts, AngII-positive cells and proinflammatory M1 macrophages, whereas the amount of anti-inflammatory M2 macrophages was reduced. In addition, the renal abundance of TLR4, nuclear p65 and IL-6 was increased, indicating activation of the NF-κB pathway, without evidence of simultaneous activation of the NLRP3 cascade. Losartan treatment decreased cortical collagen-1 deposition, myofibroblasts and AngII-positive cells, and partially restored renal M2, but had no significant effect on albuminuria, glomerulosclerosis or NF-κB activation. Combined Losartan+PDTC prevented all the observed abnormalities. Discussion/conclusion Simultaneous blockade of renal AngII and inhibition of the NF-κB pathway may represent a novel alternative to limit the decline of renal function with age.

Bioinformatics and molecular docking reveal Cryptotanshinone as the active anti-inflammation component of Qu-Shi-Xie-Zhuo decoction by inhibiting S100A8/A9-NLRP3-IL-1β signaling

BackgroundGout is a common type of arthritis marked by monosodium urate (MSU) crystal deposition in joints, triggering an inflammatory response. Qu-Shi-Xie-Zhuo (QSXZ), a traditional Chinese medicine (TCM) formula, has been clinically used for the treatment of gouty arthritis (GA). PurposeThe study sought to examine the impact of QSXZ on GA and to delve into the pharmacological mechanisms that underlie its effects. MethodsThe chemical constituents of QSXZ were analyzed through UPLC-MS. MSU-induced acute gouty arthritis (AGA) and subcutaneous (SC) air pouch models in mice were employed to evaluate the anti-inflammatory properties of QSXZ and its primary active compound, Cryptotanshinone (CTS). To investigate the therapeutic mechanisms of QSXZ, we used MS-based network pharmacology, transcriptomic analysis, molecular docking and multiscale bioassays. ResultsTreatment of QSXZ revealed a significant reduction of inflammatory cell infiltration and the expression of pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin -1β (IL-1β). Based on UPLC/MS/MS results, 49 components were considered the active ingredients of QSXZ. Network pharmacology analysis indicated that QSXZ regulates multiple inflammation-related pathways. Subsequent transcriptomic analysis showed that QSXZ regulates gene expression of S100A8 and S100A9. Our investigation observed an increased expression of S100A8 and S100A9 in monocytes derived from gout patients. Molecular docking and molecular dynamics simulation analysis revealed the binding pattern and interaction between QSXZ active compound CTS and S100A8/A9, and subsequent surface plasmon resonance (SPR) and cell thermal shift assay (CETSA) experiments verified the direct interaction between them. To investigate the mechanisms of action, we conducted RT-PCR, Western blotting, immunohistochemistry, flow cytometry, and measured the inflammatory response. Our findings highlight the pathogenic role of S100A8/A9 mediated TLR4-NLRP3 axis in gout and review outstanding therapeutic effects of QSXZ and its primary active compound CTS on MSU-induced experimental models. ConclusionsIn summary, this study substantiates the therapeutic potential of QSXZ and its primary active compound CTS, as promising alternative treatments for GA. Our findings provide valuable insight into the critical pharmacological mechanism of QSXZ in regulating inflammation, highlighting its potential therapeutic effects in GA management.

Thelazia leesei Railliet & Henry, 1910 (Spirurida: Thelaziidae) of dromedary camel Camelus dromedarius: further morphological description, molecular characterization, and epidemiology in Iran

BackgroundIn camels, thelaziosis is mainly caused by Thelazia leesei Railliet & Henry, 1910, a little-known eyeworm species. Given the paucity of scientific data, this study aimed to provide new insights into the morphology, molecular characterization, and phylogenetic relationship of T. leesei and its occurrence in camels from Iran, where animals suffer from the high burden of eyeworms.MethodsFrom December 2020 to November 2022, slaughtered camels (n = 400) of different sex and age groups were examined in Sistan-va-Baluchestan province in Southeast Iran’s local abattoirs. Adult eyeworms were fixed and stored for morphological identification by light and scanning electron microscopy (SEM). Polymerase chain reaction (PCR) products corresponding to the partial sequences of the mitochondrial cytochrome c oxidase subunit I (cox1) of eyeworms were Sanger sequenced and analyzed phylogenetically.ResultsA total of 118 (29.5%) camels from all five counties examined were infected with eyeworms, with an abundance of 0.9 and a mean intensity of 3.2 (i.e., up to 18 worms from a single animal). The infection rate was higher in camels older than 4 years of age (P = 0.01901). Lachrymation was associated with infection in animals (P < 0.00001). The morphology of our specimens resembled that of T. leesei, with the exception of the position of the nerve ring and esophagus length. Genetic analysis showed that the cox1 partial sequences of our T. leesei specimens had genetic distances of 8.8% to 13.5% compared with other Thelazia species.ConclusionsOn the basis of the morphometrics and morphological characteristics, we identified our specimens as T. leesei. In the phylogenetic tree, T. leesei herein isolated formed a monophyletic group together with its congeners, and T. leesei formed a sister clade to T. lacrymalis. In addition, we demonstrated the epidemiology of the infestation of T. leesei in camels in the endemic areas of southeastern Iran. The data presented are crucial for better understanding the pathogenic role of T. leesei and developing effective treatment strategies. In particular, studies on the intermediate host(s) of T. leesei in these regions will support effective control strategies for this parasitosis.Graphical

Association between urinary heavy metal/trace element concentrations and kidney function: a prospective study

Abstract Background Chronic kidney disease (CKD) is an important public health problem. Although cross-sectional studies have identified many heavy metals/trace elements associated with reduced kidney function, prospective studies are needed to determine the pathogenic role of these elements in the development and progression of CKD. Methods To explore the association between baseline urinary heavy metal/trace element concentrations and long-term impaired kidney function (IKF)/CKD, as well as the incidence of rapid decline in kidney function in a population-based exploratory prospective study, we mean age 51.9 years at baseline) whose urinary trace elements concentrations have been determined by inductively coupled plasma mass spectrometry (ICP-MS). IKF was defined by a reduced estimated glomerular filtration rate (eGFR) between 60-90 mL/min/1.73 m2, and CKD was defined as an eGFR&amp;lt;60 mL/min/1.73 m2. Rapid eGFR decline was defined as a decrease≥3 mL/min/1.73 m2 /year. Results Over a mean follow-up of 12.5 years, 123 participants (2.6%) experienced rapid decline in kidney function, and 1455 (31.7%) developed IKF or CKD. After adjusting for covariates including baseline eGFR, we found that urinary vanadium (HR=1.07, 1.03-1.12), cobalt (HR=1.69, 1.21-2.37), nickel (HR=1.19, 1.08-1.3), copper (HR=1.03, 1.01-1.06), selenium (HR=1.33, 1.02-1.73), molybdenum (HR=1.48, 1.2-1.82) and iodine (HR=1.1, 1.02-1.2) were associated with an increased risk of new incident IKF or CKD cases during the follow-up. Also, urinary copper (OR=1.12, 1.04-1.21), silver (OR=1.83, 1-3.35), molybdenum (OR=1.02, 1.01-1.04) and cadmium (OR=1.05, 1.01-1.09) were associated with an increased risk of rapid eGFR decline. Conclusion In the general population, several urinary heavy metals/trace elements are associated with a rapid decline in kidney function or new cases of IKF/CKD.

In silicon desinging of RANKL-targeting vaccine for protection of osteoporosis based on the epitope of Denosumab

BackgroundLife quality of osteoporosis patients is affected significantly due to the severely complications of fracture and pain. RANKL, indicated as the key mediator of osteoporosis, plays a pathogenic role of osteoclasts induction. To target this program, two medications, bisphosphonate and Denosumab, were developed and achieved remarkable advantages in clinics. Unfortunately, fracture-related side-effects always emerge unavoidably, after either long-term administration of bisphosphonates or Denosumab withdrawing. To address these challenges, vaccine-based approach has been adopted to achieve sustainable protection through induction and maintenance of effective antibodies in mild level over decades. MethodsA Denosumab binding peptide was firstly identified as the basic component of vaccine. This peptide was then fused with diphtheria toxin T domain, a widely used adjuvant protein. Its capabilities to penetrate the autologous tolerance and induce the immune responses was then demonstrated with in-silicon evaluation. Finally, the efficacy of the DR3 vaccine was assessed through immunization on the human RANKL transgenic mice model of osteoporosis. ResultsThe DTT-RANKL(220–245)3 vaccine, termed as DR3, were predicted as highly antigenic and non-allergenicity. This molecule was comprised of 46.5 % of helix, 8.5 % strand and 45.1 % coil, the optimized Z-value of the tertiary structure was 6.39, and the favored area in the Ramachandran plot was 96.1 % after refinement. Molecular docking showed a tight binding of DR3 vaccine to TLR2 (−9.2 kcal/mol) and TLR4 (−9.5 kcal/mol). In addition, the immune stimulation indicated robust responses post administration of DR3 vaccine, including high level production of of antibodies and cytokines, activated T and B lymphocytes, and the long-last immune memory. In agree with the simulation, vaccinated mice generated high titers anti-hRANKL antibodies and elevated levels of IL-4 and IL-10 at 7th week post immunization. ConclusionDR3 vaccine was aroused to benefit the prevention and treatment of osteoporosis, and other bone-resorptive diseases potentially.

The serine palmitoyltransferase core subunit StLcb2 regulates sphingolipid metabolism and promotes Setosphaeria turcica pathogenicity by modulating appressorium development

The fungal pathogen Setosphaeria turcica (S. turcica) causes northern corn leaf blight (NCLB), resulting in significant yield and economic losses in maize. To elucidate the metabolic pathways essential for its pathogenicity, we investigated the metabolome of S. turcica during appressorium development, a critical stage for host infection. Our analysis indicated a substantial enrichment of sphingosine and related compounds during this phase. The application of chemical inhibitors to disrupt sphingolipid metabolism confirmed their pivotal role in appressorium formation and pathogenicity. Additionally, silencing of the serine palmitoyl transferase (Spt) core subunit gene StLCB2 led to significant alterations in fungal morphology and growth, accompanied by changes in cell membrane integrity, surface hydrophobicity, melanin, and sphingosine synthesis. These findings underscore the importance of sphingolipids in the pathogenicity of S. turcica and suggest that targeting specific components of the sphingolipid pathway could aid in developing novel fungicides or genetically engineered maize varieties with increased resistance to NCLB.

Pathogenic role of acyl coenzyme A binding protein (ACBP) in Cushing's syndrome.

Cushing's syndrome is caused by an elevation of endogenous or pharmacologically administered glucocorticoids. Acyl coenzyme A binding protein (ACBP, encoded by the gene diazepam binding inhibitor, Dbi) stimulates food intake and lipo-anabolic reactions. Here we found that plasma ACBP/DBI concentrations were elevated in patients and mice with Cushing's syndrome. We used several methods for ACBP/DBI inhibition in mice, namely, (1) induction of ACBP/DBI autoantibodies, (2) injection of a neutralizing monoclonal antibody, (3) body-wide or hepatocyte-specific knockout of the Dbi gene, (4) mutation of the ACBP/DBI receptor Gabrg2 and (5) injections of triiodothyronine or (6) the thyroid hormone receptor-β agonist resmetirom to block Dbi transcription. These six approaches abolished manifestations of Cushing's syndrome such as increased food intake, weight gain, excessive adiposity, liver damage, hypertriglyceridaemia and type 2 diabetes. In conclusion, it appears that ACBP/DBI constitutes an actionable target that is causally involved in the development of Cushing's syndrome.

Report of a novel missense TDP1 variant in a Pakistani family affected with an extremely rare disorder congenital spinocerebellar ataxia with axonal neuropathy type 1 (SCAN1)

BackgroundSpinocerebellar ataxia with axonal neuropathy type 1 (OMIM: 607250) is an extremely rare autosomal recessive disorder caused by a mutation in the tyrosyl-DNA phosphodiesterase 1 (TDP1) gene. Only a single missense variant (p.His493Arg) in this gene has been reported. This variant was found in three Arab families with a possible common founder effect.Methods and ResultsWe report a female patient born to a consanguineous Pakistani family segregating autosomal recessive spinocerebellar ataxia with axonal neuropathy type 1. The patient presents additional clinical features distinct from previously reported Arab families including congenital onset of the disease. We performed whole exome sequencing with the patient’s DNA and identified a novel missense variant (NC_000014.9:g.89991982C > T; p.His478Tyr) in exon 13 of the TDP1 gene. Sanger sequencing was performed to verify the autosomal recessive segregation of the p.His478Tyr variant in the family.ConclusionThe current study expands both the clinical and mutation spectrum of the TDP1 associated spinocerebellar ataxia with axonal neuropathy type 1 and increases the body of evidence that supports the pathogenic role of TDP1 in cerebellar ataxias with peripheral neuropathy.

The Role of Viral Pathogens in Horse Respiratory Diseases: A Cytological and Molecular Approach Using Next-Generation Sequencing

The Role of Viral Pathogens in Horse Respiratory Diseases: A Cytological and Molecular Approach Using Next-Generation Sequencing

The PLSDB 2025 update: enhanced annotations and improved functionality for comprehensive plasmid research.

Plasmids are extrachromosomal DNA molecules in bacteria and archaea, playing critical roles in horizontal gene transfer, antibiotic resistance, and pathogenicity. Since its first release in 2018, our database on plasmids, PLSDB, has significantly grown and enhanced its content and scope. From 34513 records contained in the 2021 version, PLSDB now hosts 72360 entries. Designed to provide life scientists with convenient access to extensive plasmid data and to support computer scientists by offering curated datasets for artificial intelligence (AI) development, this latest update brings more comprehensive and accurate information for plasmid research, with interactive visualization options. We enriched PLSDB by refining the identification and classification of plasmid host ecosystems and host diseases. Additionally, we incorporated annotations for new functional structures, including protein-coding genes and biosynthetic gene clusters. Further, we enhanced existing annotations, such as antimicrobial resistance genes and mobility typing. To accommodate these improvements and to host the increase plasmid sets, the webserver architecture and underlying data structures of PLSDB have been re-reconstructed, resulting in decreased response times and enhanced visualization of features while ensuring that users have access to a more efficient and user-friendly interface. The latest release of PLSDB is freely accessible at https://www.ccb.uni-saarland.de/plsdb2025.

Identification of biallelic intronic EPM2A mutations in a Lafora disease kindred.

Lafora disease (LD) is a severe autosomal recessive disease, which usually presents as seizure and myoclonus, followed by behavioral changes, dysarthria, intellectual decline, and finally progressed to dementia and a vegetative state. The main cause of LD is the loss-of-function mutations in EPM2A and NHLRC1 that encode laforin and malin, respectively. Targeted genetic testing is the gold standard to confirm the diagnosis of LD. To describe the pathogenic role of biallelic EPM2A intronic mutations carried by patients in a family diagnosed as LD. Here, we present clinical findings in a patient presenting with epileptic seizures and Lafora bodies in muscle biopsy. Long-read DNA and RNA sequencing were performed to identify the causative mutation. Western blot and qPCR confirmed the pathogenic role of biallelic EPM2A intronic mutations. Genetic testing identified two intronic mutations in EPM2A which caused aberrant mRNA splicing. c.301+1 G > A in EPM2A caused aberrant splicing at donor site and resulted in intron retention in transcript NM_005670.4, while c.476+14860 C > A caused aberrant splicing in transcript NM_001368129.2 and NM_001368132.1. Our findings expand the spectrum of variants in LD disease, additionally providing evidence linking non-coding regulatory regions mutations to LD disease.

Recurrent BMP4 variants in exon 4 cause non-HFE-associated hemochromatosis via the BMP/SMAD signaling pathway

BackgroundHereditary hemochromatosis (HH) is an iron overload disorder and can be caused by variants in non-HFE genes in Chinese patients. However, there is still a considerable proportion of patients suffering from unexplained iron overload. In our previous study, we had identified the p.R269Q variant in exon 4 of the Bone morphogenetic protein 4 (BMP4) gene in Chinese patients with unexplained primary iron overload by Whole Exome sequencing, and then the BMP4 p.H251Y variant was identified by Sanger sequencing in a Chinese patient with secondary iron overload. Our study aimed to explore the pathogenicity and underlying mechanism of BMP4 p.H251Y and BMP4 p.R269Q variants in patients with iron overload.MethodsSanger sequencing was conducted to identify the novel variants in the BMP4 gene of patients with unexplained iron overload. MRI and liver biopsy were used to display iron overload in the liver of the patient harboring the BMP4 p.H251Y variant. The BMP4 and hepcidin levels in BMP4 knockdown and BMP4 variant cells were examined by enzyme-linked immunosorbent assay. The effects of BMP4 p.H251Y and BMP4 p.R269Q variants on the hepcidin-regulation pathway were studied.ResultsOne of 54 HH patients (1.85%) harbored the BMP4 p.R269Q variant. One of 148 patients (0.68%) with secondary hemochromatosis harbored the BMP4 p.H251Y variant, and these two variants were not found in 100 Chinese general population. For the patient harboring the BMP4 p.H251Y variant, abdominal MRI and Perl's staining of liver tissue displayed iron overload in the liver. Cells transfected with the BMP4 p.H251Y and p.R269Q variants showed down-regulation of hepcidin level and BMP/SMAD pathway compared with cells transfected with the wild-type BMP4 vector.ConclusionThe BMP4 p.H251Y and p.R269Q variants can downregulate hepcidin levels by inhibiting the BMP/SMAD axis, suggesting they may play pathogenic roles in iron overload.

Transcriptomic analysis reveals pathogenicity mechanisms of Phytophthora capsici in black pepper.

The devastating disease "quick wilt" or "foot rot" is caused by the oomycete Phytophthora capsici Leonian and is affecting the economically significant spice crop black pepper (Piper nigrum L.). The details on the mechanism of interaction of P. capsici with its host black pepper remain poorly understood, hindering efforts to enhance disease resistance. To address this knowledge gap, we conducted an RNA-seq analysis to investigate the gene expression profile of P. capsici infecting black pepper. Comparative transcriptome analysis between axenic culture, and early and late infection stages of P. capsici revealed a substantial number of differentially expressed genes. Our findings demonstrate the induction of metabolic pathways, signaling cascades, and crucial pathogenicity-related processes during infection of black pepper by P. capsici. Specifically, we observed orchestrated expression of cell wall-degrading enzymes, effectors, and, detoxifying transporters at different infection time points, implicating their roles in pathogenicity. The expression patterns of key pathogenicity-associated genes, including effectors, were validated using reverse transcription quantitative real-time PCR. The effectiveness of agroinfiltration-mediated transient expression in black pepper for functional studies of effectors is also demonstrated in this study. Overall, this study establishes a strong foundation for further studies elucidating the pathogenic mechanisms employed by P. capsici infecting black pepper and for developing effective disease management strategies. Future investigations building upon these findings are essential for advancing our understanding of this pathosystem and for implementing targeted approaches to mitigate black pepper foot rot.

Cholesterol crystals in the pathogenesis of atherosclerosis.

The presence of cholesterol crystals (CCs) in tissues was first described more than 100 years ago. CCs have a pathogenic role in various cardiovascular diseases, including myocardial infarction, aortic aneurysm and, most prominently, atherosclerosis. Although the underlying mechanisms and signalling pathways involved in CC formation are incompletely understood, numerous studies have highlighted the existence of CCs at various stages of atheroma progression. In this Review, we summarize the mechanisms underlying CC formation and the role of CCs in cardiovascular disease. In particular, we explore the established links between lipid metabolism across various cell types and the formation of CCs, with a focus on CC occurrence in the vasculature. We also discuss CC-induced inflammation as one of the pathogenic features of CCs in the atheroma. Finally, we summarize the therapeutic strategies aimed at reducing CC-mediated atherosclerotic burden, including approaches to inhibit CC formation in the vasculature or to mitigate the inflammatory response triggered by CCs. Addressing CC formation might emerge as a crucial component in our broader efforts to combat cardiovascular disease.