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Aging Jun 2024Chronic atrophic gastritis (CAG) is a chronic inflammatory disease and precancerous lesion in stomach cancer. Abnormal activation cellular ferroptosis further damages...
Chronic atrophic gastritis (CAG) is a chronic inflammatory disease and precancerous lesion in stomach cancer. Abnormal activation cellular ferroptosis further damages gastric tissue, which is susceptible to inflammation. Luteolin has powerful anti-inflammatory and regulatory potential for cellular ferroptosis. We aimed to clarify the involvement of luteolin in inflammation and ferroptosis during CAG. Luteolin targets were searched to identify intersecting genes in the chronic atrophic gastritis disease database. The AGE-RAGE pathway is a potential target of luteolin for the treatment of chronic atrophic gastritis and a binding site between luteolin and RAGE was predicted through a computer simulation of molecular docking. We established a CAG rat model using N-methyl-N-nitro-N-nitroguanidine. The therapeutic effect of luteolin on CAG was detected using western blotting, qPCR, hematoxylin and eosin staining, lipid oxidation (MDA), and Fe assays. Luteolin inhibited the AGE-RAGE signaling pathway and reduced the inflammatory response in gastric tissues. Additionally, luteolin downregulated the concentration of (MDA) and Fe, and CAG downregulated the expression levels of ACSL4 and NOX1 and upregulated the expression levels of FIH1 and GPX4 ferroptosis-related proteins, thus inhibiting the ferroptosis of gastric tissue cells, which had a therapeutic effect on CAG.
PubMed: 38917486
DOI: 10.18632/aging.205969 -
JCI Insight Jun 2024The immune benefits of vitamin D3 supplementation beyond calcium and phosphate maintenance are highly clinically debated. Kidney expression of CYP27B1 is the source of...
The immune benefits of vitamin D3 supplementation beyond calcium and phosphate maintenance are highly clinically debated. Kidney expression of CYP27B1 is the source of endocrine, circulating 1,25(OH)2D3 (active form of vitamin D) that maintains serum calcium and phosphate. 1,25(OH)2D3 may also be made by the CYP27B1 enzyme in non-renal cells, like immune cells, in a process driven by cellular availability of 25(OH)D3 and inflammation. Due to the endocrine nature of 1,25(OH)2D3 in circulation, it is difficult to discern between these two sources. We recently created a regulatory deletion model of Cyp27b1 (M1/M21-DIKO) where mice have normal inflammatory-regulated Cyp27b1 expression in non-renal tissues (unlike global Cyp27b1-KO), but no expression within kidney. Here, utilizing on-tissue chemical derivatization and Matrix Assisted Laser Desorption Ionization-Mass Spectrometry Imaging (MALDI-MSI), we investigated the distribution of 1,25(OH)2D3 and 25(OH)D3 in the kidney, liver, spleen, and thymus. MALDI-MSI demonstrated increased 1,25(OH)2D3 in non-renal tissues such as the spleen after vitamin D3 supplementation in M1/M21-DIKO mice. Additionally, from this we found increased Il4 and decreased Tnfa in the spleen after vitamin D3 supplementation. Taken together, these data demonstrate non-renal production of 1,25(OH)2D3 in vivo and provide a consequence of vitamin D3 supplementation and non-renal 1,25(OH)2D3 production in cytokine changes.
PubMed: 38916957
DOI: 10.1172/jci.insight.181763 -
BioRxiv : the Preprint Server For... Jun 2024The spleen tyrosine kinase (SYK) and high affinity immunoglobulin epsilon receptor subunit gamma (FCER1G) interaction has a major role in the normal innate and adaptive...
The spleen tyrosine kinase (SYK) and high affinity immunoglobulin epsilon receptor subunit gamma (FCER1G) interaction has a major role in the normal innate and adaptive immune responses, but dysregulation of this interaction is implicated in several human diseases, including autoimmune disorders, hematological malignancies, and Alzheimer's Disease. Development of small molecule chemical probes could aid in studying this pathway both in normal and aberrant contexts. Herein, we describe the miniaturization of a time-resolved fluorescence resonance energy transfer (TR-FRET) assay to measure the interaction between SYK and FCER1G in a 1536-well ultrahigh throughput screening (uHTS) format. The assay utilizes the His-SH2 domains of SYK, which are indirectly labeled with anti-His-terbium to serve as TR-FRET donor and a FITC-conjugated phosphorylated ITAM domain peptide of FCER1G to serve as acceptor. We have optimized the assay into 384-well HTS format and further miniaturized the assay into a 1536-well uHTS format. Robust assay performance has been achieved with a Z' factor > 0.8 and signal-to-background (S/B) ratio > 15. The utilization of this uHTS TR-FRET assay for compound screening has been validated by a pilot screening of 2,036 FDA-approved and bioactive compounds library. Several primary hits have been identified from the pilot uHTS. One compound, hematoxylin, was confirmed to disrupt the SYK/FECR1G interaction in an orthogonal protein-protein interaction assay. Thus, our optimized and miniaturized uHTS assay could be applied to future scaling up of a screening campaign to identify small molecule inhibitors targeting the SYK and FCER1G interaction.
PubMed: 38915662
DOI: 10.1101/2024.06.11.598473 -
BioRxiv : the Preprint Server For... Jun 2024Spleen tyrosine kinase (SYK) is a non-receptor tyrosine kinase that is activated by phosphorylation events downstream of FcR, B-cell and T-cell receptors, integrins, and...
Spleen tyrosine kinase (SYK) is a non-receptor tyrosine kinase that is activated by phosphorylation events downstream of FcR, B-cell and T-cell receptors, integrins, and C-type lectin receptors. When the tandem Src homology 2 (SH2) domains of SYK bind to phosphorylated immunoreceptor tyrosine-based activation motifs (pITAMs) contained within these immunoreceptors, or when SYK is phosphorylated in interdomain regions A and B, SYK is activated. SYK gain-of-function (GoF) variants were previously identified in six patients that had higher levels of phosphorylated SYK and phosphorylated downstream proteins JNK and ERK. Furthermore, the increased SYK activation resulted in the clinical manifestation of immune dysregulation, organ inflammation, and a predisposition for lymphoma. The knowledge that the SYK GoF variants have enhanced activity was leveraged to develop a SYK NanoBRET cellular target engagement assay in intact live cells with constructs for the SYK GoF variants. Herein, we developed a potent SYK-targeted NanoBRET tracer using a SYK donated chemical probe, MRL-SYKi, that enabled a NanoBRET cellular target engagement assay for SYK GoF variants, SYK(S550Y), SYK(S550F), and SYK(P342T). We determined that ATP-competitive SYK inhibitors bind potently to these SYK variants in intact live cells. Additionally, we demonstrated that MRL-SYKi can effectively reduce the catalytic activity of SYK variants, and the phosphorylation levels of SYK(S550Y) in an epithelial cell line (SW480) stably expressing SYK(S550Y).
PubMed: 38915605
DOI: 10.1101/2024.06.12.598544 -
NPJ Vaccines Jun 2024Gammaherpesviruses are oncogenic viruses that establish lifelong infections and are significant causes of morbidity and mortality. Vaccine strategies to limit...
Gammaherpesviruses are oncogenic viruses that establish lifelong infections and are significant causes of morbidity and mortality. Vaccine strategies to limit gammaherpesvirus infection and disease are in development, but there are no FDA-approved vaccines for Epstein-Barr or Kaposi sarcoma herpesvirus. As a new approach to gammaherpesvirus vaccination, we developed and tested a replication-deficient virus (RDV) platform, using murine gammaherpesvirus 68 (MHV68), a well-established mouse model for gammaherpesvirus pathogenesis studies and preclinical therapeutic evaluations. We employed codon-shuffling-based complementation to generate revertant-free RDV lacking expression of the essential replication and transactivator protein encoded by ORF50 to arrest viral gene expression early after de novo infection. Inoculation with RDV-50.stop exposes the host to intact virion particles and leads to limited lytic gene expression in infected cells yet does not produce additional infectious particles. Prime-boost vaccination of mice with RDV-50.stop elicited virus-specific neutralizing antibody and effector T cell responses in the lung and spleen. In contrast to vaccination with heat-inactivated WT MHV68, vaccination with RDV-50.stop resulted in a near complete abolishment of virus replication in the lung 7 days post-challenge and reduction of latency establishment in the spleen 16 days post-challenge with WT MHV68. Ifnar1 mice, which lack the type I interferon receptor, exhibit severe disease and high mortality upon infection with WT MHV68. RDV-50.stop vaccination of Ifnar1 mice prevented wasting and mortality upon challenge with WT MHV68. These results demonstrate that prime-boost vaccination with a gammaherpesvirus that is unable to undergo lytic replication offers protection against acute replication, impairs the establishment of latency, and prevents severe disease upon the WT virus challenge. Our study also reveals that the ability of a gammaherpesvirus to persist in vivo despite potent pre-existing immunity is an obstacle to obtaining sterilizing immunity.
PubMed: 38914546
DOI: 10.1038/s41541-024-00908-x -
ESMO Open Jun 2024Paclitaxel resistance limits durability of response in patients with initial clinical benefit. Overexpression of spleen tyrosine kinase (SYK) has been proposed as a...
BACKGROUND
Paclitaxel resistance limits durability of response in patients with initial clinical benefit. Overexpression of spleen tyrosine kinase (SYK) has been proposed as a possible resistance mechanism. This phase I trial evaluated the safety and preliminary activity of the SYK inhibitor TAK-659 combined with paclitaxel in patients with advanced taxane-refractory solid tumors.
PATIENTS AND METHODS
Patients with advanced solid tumors and prior progression on taxane-based therapy received intravenous infusion of paclitaxel on days 1, 8, and 15 plus oral TAK-659 daily in 28-day cycles. The dose-escalation phase included six cohorts treated at different dose levels; the dose-expansion phase included patients with ovarian cancer treated at the highest dose level. Toxicity was graded using the National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0. Efficacy was evaluated using Response Evaluation Criteria in Solid Tumors version 1.1.
RESULTS
Our study included 49 patients. Maximum tolerated dose was not reached, but higher rates of adverse events were observed at higher dose levels. There were no treatment-related deaths. The most common treatment-related adverse events of any grade were increased aspartate aminotransferase (n = 31; 63%), increased alanine aminotransferase (n = 26; 53%), decreased neutrophil count (n = 26; 53%), and decreased white blood cell count (n = 26; 53%). Most adverse events were either grade 1 or 2. In the 44 patients with evaluable disease, 12 (27%) had stable disease as the best overall response, including three patients with prolonged stable disease, and 4 patients (9%) achieved a partial response.
CONCLUSIONS
The combination of paclitaxel and TAK-659 showed preliminary activity possibly overcoming resistance to taxane-based therapy as well as a tolerable safety profile in patients with advanced solid tumors.
Topics: Humans; Paclitaxel; Female; Middle Aged; Aged; Neoplasms; Male; Adult; Antineoplastic Combined Chemotherapy Protocols; Drug Resistance, Neoplasm; Taxoids; Maximum Tolerated Dose; Syk Kinase
PubMed: 38914452
DOI: 10.1016/j.esmoop.2024.103486 -
Microbiology Spectrum Jun 2024an emerging fungal pathogen, predominately colonizes human skin leading to serious invasive infections in humans. Though it is assumed that skin colonization can lead...
UNLABELLED
an emerging fungal pathogen, predominately colonizes human skin leading to serious invasive infections in humans. Though it is assumed that skin colonization can lead to invasive infection, dissemination potential of from skin to internal organs is still unknown. In this study, immunocompetent and immunocompromised mouse models of intradermal skin infection were used to compare the dissemination potential of to internal organs. Our results suggest that persists in the skin tissue of both immunocompetent and immunocompromised infected mice even at 30 days post-infection. Furthermore, can readily disseminate from skin tissue to internal organs such as the spleen and kidney as early as 24 h post-infection and was detected until 30 days post-infection. Taken together, our findings for the first time indicate that murine skin intradermally infected with can readily disseminate to internal organs and cause invasive infections.
IMPORTANCE
is a multi-drug-resistant emerging fungal pathogen colonizes the human skin and causes life-threatening infections. However, whether can disseminate from the skin to internal organs is unclear. Understanding the dissemination potential of in both immunocompetent and immunocompromised hosts is necessary to monitor susceptible individuals and to develop novel approaches to prevent and treat this emerging fungal pathogen. Using mouse models of intradermal skin infection, our findings report a novel observation that mice skin intradermally infected with can readily disseminate to internal organs leading to systemic disease. These findings help explain the colonization, persistence, and dissemination potential of in immunocompetent and immunocompromised hosts and reveal that skin infection is a potential source of invasive infection.
PubMed: 38912805
DOI: 10.1128/spectrum.00127-24 -
The Indian Journal of Radiology &... Jul 2024Trauma is a significant cause of morbidity and mortality worldwide among children. Nonoperative management is the standard of care in hemodynamically stable children...
Trauma is a significant cause of morbidity and mortality worldwide among children. Nonoperative management is the standard of care in hemodynamically stable children with blunt abdominal solid organ injury. Embolization is a potential pathway, which has shown increasing evidence for benefit in adult trauma patients. However, the data in children is limited. A retrospective analysis of hospital data of all children (<18 years of age), presenting to a tertiary-care trauma center in India, with history of blunt trauma from January 2021 to June 2023, was performed. Preprocedural imaging, angiographic and embolization details, number of blood transfusions, and length of hospital stay were assessed. Two hundred and sixteen children (average age: 11.65 years) presented with a history of abdominal trauma during the study period. Eighty four children were FAST positive, out of whom, 67 patients had abdominal solid organ injury on computed tomography. Liver was the most commonly injured solid organ ( = 45), followed by the spleen and kidney. Ten children had solid abdominal organ arterial injuries for which eight children underwent embolization. The average length of hospital stay in embolization group ( = 8) was 4 days, as compared to 11 days in children undergoing operative management ( = 2). At 6 months follow-up, all children were asymptomatic. Superselective embolization is a safe and feasible procedure in appropriately selected children with abdominal injury.
PubMed: 38912245
DOI: 10.1055/s-0043-1778057 -
Frontiers in Cellular and Infection... 2024is an intracellular parasite of importance to human and veterinary health. The structure and diversity of the genotype population of varies considerably with respect...
INTRODUCTION
is an intracellular parasite of importance to human and veterinary health. The structure and diversity of the genotype population of varies considerably with respect to geography, but three lineages, type I, II and III, are distributed globally. Lineage III genotypes are the least well characterized in terms of biology, host immunity and virulence. Once a host is infected with , innate immune mechanisms are engaged to reduce the parasite burden in tissues and create a pro-inflammatory environment in which the T1 response develops to ensure survival. This study investigated the early cellular immune response of Swiss-Webster mice post intraperitoneal infection with 10 tachyzoites of four distinct non-clonal genotypes of lineage III and a local isolate of ToxoDB#1. The virulence phenotype, cumulative mortality (CM) and allele profiles of ROP5, ROP16, ROP18 and GRA15 were published previously.
METHODS
Parasite dissemination in different tissues was analyzed by real-time PCR and relative expression levels of IFNγ, IL12-p40, IL-10 and TBX21 in the cervical lymph nodes (CLN), brain and spleen were calculated using the ΔΔCt method. Stage conversion was determined by detection of the BAG1 transcript in the brain.
RESULTS
Tissue dissemination depends on the virulence phenotype but not CM, while the TBX21 and cytokine levels and kinetics correlate better with CM than virulence phenotype. The earliest detection of BAG1 was seven days post infection. Only infection with the genotype of high CM (69.4%) was associated with high T-bet levels in the CLN 24 h and high systemic IFNγ expression which was sustained over the first week, while infection with genotypes of lower CM (38.8%, 10.7% and 6.8%) is characterized by down-regulation and/or low systemic levels of IFNγ. The response intensity, as assessed by cytokine levels, to the genotype of high CM wanes over time, while it increases gradually to genotypes of lower CM.
DISCUSSION
The results point to the conclusion that the immune response is not correlated with the virulence phenotype and/or allele profile, but an early onset, intense pro-inflammatory response is characteristic of genotypes with high CM. Additionally, high IFNγ level in the brain may hamper stage conversion.
Topics: Toxoplasma; Animals; Mice; Virulence; Genotype; Cytokines; Toxoplasmosis, Animal; Phenotype; Female; Spleen; Brain; Protozoan Proteins; Disease Models, Animal; Lymph Nodes; Interferon-gamma; T-Box Domain Proteins; Immunity, Cellular
PubMed: 38912206
DOI: 10.3389/fcimb.2024.1414067 -
Biomedical Reports Aug 2024During a routine ultrasound examination of the abdomen, a 60-year-old male patient was diagnosed with mass in the tail of the pancreas. However, computed tomography (CT)...
During a routine ultrasound examination of the abdomen, a 60-year-old male patient was diagnosed with mass in the tail of the pancreas. However, computed tomography (CT) suggested that the lesion was an intrapancreatic accessory spleen (IPAS). IPAS is a congenital anomaly, which usually does not present with symptoms. IPAS occurs during embryologic splenic development when a portion of the splenic tissue fails to fuse with the main body of the spleen. IPAS does not require treatment, except when it is combined with idiopathic thrombocytopenic purpura. In the present case, the diagnosis of IPAS was confirmed using magnetic resonance imaging (MRI). On CT and MRI, the IPAS had a density and intensity comparable with that of the spleen in all plain and contrast-enhanced phases. Due to comorbidities, the patient refused further evaluation or surgery. The lesion was periodically monitored using CT every 1-2 years. Since the tumour was stable during the 7-year follow-up, it was concluded that it was an IPAS. In patients that cannot undergo surgery, a characteristic location (near the spleen) and imaging features (such as a 'zebra-patterned' enhancement in the arterial phase on CT and high signal intensity on diffusion-weighted imaging sequences on MRI, which is comparative to that of the normal spleen) may allow for a diagnose of IPAS with a high level of certainty. Being aware of this condition could aid a correct diagnosis of IPAS and prevent unnecessary surgery.
PubMed: 38912170
DOI: 10.3892/br.2024.1801