IRAK family in inflammatory autoimmune diseases

Exploring the mechanism of Cynanchum paniculatum (Bunge) Kitag's therapeutic strategy for rheumatoid arthritis: integrating network pharmacology, molecular docking and in vivo experiments

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by joint swelling, cartilage degradation, and joint deformity. The traditional Chinese herb Cynanchum paniculatum (Bunge) Kitag has been utilized in the management of RA, but the underlying mechanisms are unknown. This study utilized network pharmacology analysis to identify 26 active compounds associated with RA treatment and elucidate their interactions with 23 critical targets linked to RA. Subsequently, molecular docking studies revealed eight compounds with the capacity to bind to multiple key targets, with butyl isobutyl phthalate and geranyl acetone emerging as the most promising candidates based on their drug-likeness properties. To validate these findings, a rat model of adjuvant-induced arthritis was employed. Oral administration of geranyl acetone led to a significant reduction in paw swelling and pro-inflammatory markers, including TNF-α, IL-6, IL-1β, and MPO. Furthermore, it resulted in histological improvements in ankle tissues, all without adverse effects on weight or immune organs. Mechanistically, geranyl acetone was found to impede the progression of RA by modulating the TLR4/MyD88/NF-κB signaling pathway. In conclusion, C. paniculatum demonstrates substantial therapeutic potential for RA due to its multi-target and multi-pathway activities. Moreover, geranyl acetone, when used as a standalone agent, exhibits significant promise in alleviating RA symptoms, offering a compelling avenue for further research and potential clinical applications.

Heterobifunctional proteomimetic polymers for targeted protein degradation

The burgeoning field of targeted protein degradation (TPD) has opened new avenues for modulating the activity of previously undruggable proteins of interest. To date, TPD has been dominated by small molecules containing separate linked domains for protein engagement and recruitment of cellular degradation machinery. The process of identifying active compounds has required tedious optimization and has been successful largely against a limited set of targets with well-defined, suitable docking pockets. Here we present a polymer chemistry approach termed the HYbrid DegRAding Copolymer (HYDRAC) to overcome standing challenges associated with the development of TPD. These copolymers densely display either peptide-based or small molecule-derived degradation inducers and target-binding peptide sequences for the selective degradation of disease-associated proteins. HYDRACs are synthesized in a facile manner, are modular in design, and are highly selective. Using the intrinsically disordered transcription factor MYC as an initial proof-of-concept, difficult to drug protein target, HYDRACs containing a MYC-inhibitory peptide copolymerized with a validated degron, showed robust and selective degradation of the target protein. Treatment of tumor-bearing mice with MYC-targeted HYDRACs showed decreased cell proliferation and increased tumor apoptosis, leading to significantly suppressed tumor growth in vivo . The versatility of the platform was demonstrated by substituting the degron for recruiters of three different E3 ligases (VHL, KEAP1, and CRBN), which all maintained MYC degradation. To demonstrate generalizability, HYDRACs were further designed against a second elusive target of clinical interest, KRAS, by employing a consensus RAS binding motif. RAS-targeted HYDRACs showed degradation in two cell lines harboring separate KRAS alleles, suggesting potential pan-KRAS activity. We envision the HYDRAC platform as a generalizable approach to developing degraders of proteins of interest, greatly expanding the therapeutic armamentarium for TPD.

Trimethylamine N-oxide aggravates human aortic valve interstitial cell inflammation by regulating the macrophages polarization through a N6-methyladenosine-mediated pathway

BACKGROUND

Trimethylamine N-oxide (TMAO) is a gut microbial metabolite that promotes calcified aortic valve disease (CAVD), but the underlying mechanism remains obscure. Herein, we aim to test the hypothesis that TMAO regulated the inflammatory process in aortic valves via N6-methyladenosine (m6A) RNA methylation-mediated macrophage polarization.

METHODS

In vitro, we stimulated macrophages (Phorbol-12-Myristate-13-Acetate-induced THP-1) with TMAO and assessed the expression of methyltransferase-like 3 (Mettl3), IL-1 receptor associated kinase M (IRAK-M) and polarization markers. The interaction between YTH domain family protein 2 (YTHDF2) and IRAK-M mRNA was explored by RNA-IP and RNA decay assay. Functionally, the effects of macrophages on human aortic valve interstitial cells (AVICs) were measured via macrophage adhesion assay and co-culture system. In vivo, the influence of IRAK-M on CAVD development was verified using Irak-m-/- mice.

RESULT

Mettl3 was highly expressed while IRAK-M was decreased in human calcified aortic valves. In vitro, TMAO upregulated the expression of Mettl3, while the expression of IRAK-M, an important negative regulator of the NF-κB pathway, was remarkably decreased in macrophages. TMAO also induced classical macrophage activation (M1 polarization). Mechanistically, IRAK-M was identified as a target of Mettl3-mediated m6A modification, indicating the involvement of m6A methylation in the regulation of NF-κB activation. Moreover, RIP assay revealed the direct interaction between YTHDF2 and IRAK-M mRNA and this process was dependent on Mettl3. TMAO-treated macrophage conditioned medium induced inflammatory responses in human aortic valve interstitial cells (AVICs). In vivo experiments showed that the deletion of IRAK-M significantly accelerated the progression of aortic valve lesion in mice administrated with high-fat and choline diet (HFCD).

CONCLUSION

TMAO induces the expression of Mettl3 in macrophages. Mettl3 promotes M1 polarization of macrophages by inhibiting IRAK-M through a m6A/YTHDF2 pathway. TMAO-treated macrophages aggravate the inflammation of human AVICs.

GPx3 Promotes Functional Recovery after Spinal Cord Injury by Inhibiting Microglial Pyroptosis Through IRAK4/ROS/NLRP3 Axis

Aim: Spinal cord injury (SCI) is a catastrophic injury characterized by oxidative stress. Glutathione peroxidase 3 (GPx3) is an antioxidant enzyme that protects against immune responses in various diseases. However, the effects of GPx3 in SCI remains unclear. This study aimed to investigate the role of GPx3 in SCI and its underlying mechanisms. Results: We injected adeno-associated viruses to overexpress GPx3 in mice. Primary microglia and BV2 cells were used as in vitro models. We knocked down or overexpressed GPx3 in BV2 cells. Additionally, BV2 cells transfected with siIRAK4 were used to perform rescue experiments. A series of histological and molecular biological analyses were used to explore the role of GPx3 in SCI. Overexpression of GPx3 inhibited oxidative stress in mice, improving functional recovery after SCI. Similarly, LPS+ATP stimulation decreased GPx3 expression in microglia. Silencing of GPx3 elevated the generation of reactive oxygen species, increased the expression of IRAK4 and pro-inflammatory factors, and promoted pyroptosis in microglia. However, overexpression of GPx3 reversed these results. Moreover, silencing of IRAK4 alleviated these phenomena, which were upregulated by GPx3 deficiency. Innovation and Conclusion: Our results demonstrated that GPx3 plays a critical role in SCI by inhibiting microglial pyroptosis via the IRAK4/ROS/NLRP3 signaling pathway. Antioxid. Redox Signal. 00, 000-000.

CircCCT2/miR-146a-5p/IRAK1 axis promotes the development of head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC), a highly invasive malignancy with a poor prognosis, is one of the most common cancers globally. Circular RNAs (circRNAs) have become key regulators of human malignancies, but further studies are necessary to fully understand their functions and possible causes in HNSCC.

METHODS

CircCCT2 expression levels in HNSCC tissues and cells were measured via qPCR. CircCCT2 was characterized by Sanger sequencing, qRT-PCR, RNase R & Actinomycin D treatment, nucleoplasmic separation and FISH experiments. CCK-8 and colony formation assays were performed to determine cell proliferation, and Transwell assays were used to determine migration and invasion. A xenograft tumor model was used to study the influence of circCCT2 on HNSCC in vivo. Dual-luciferase gene reporter, RIP, western blotting, and rescue experiments, were used to explore target-binding relationships and regulatory mechanisms.

RESULTS

CircCCT2 was significantly upregulated in HNSCC tissues and cells. High circCCT2 levels were associated with advanced T stage, N stage, clinical stage and poor prognosis. Functionally, we verified that circCCT2 promotes HNSCC development in vitro and in vivo. Mechanistically, functioning as a competitive endogenous RNA (ceRNA) or miRNA sponge, circCCT2 binds directly to miR-146a-5p and increases interleukin-1 receptor-associated kinase 1 (IRAK1) levels, which enhances the malignant development of HNSCC by driving epithelial-mesenchymal transition (EMT).

CONCLUSION

CircCCT2 promotes HNSCC development through the miR-146a-5p/IRAK1 axis, revealing that circCCT2 is a potential biomarker and target for HNSCC.

PROTAC unleashed: Unveiling the synthetic approaches and potential therapeutic applications

Proteolysis-Targeting Chimeras (PROTACs) are a novel class of bifunctional small molecules that alter protein levels by targeted degradation. This innovative approach uses the ubiquitin-proteasome system to selectively eradicate disease-associated proteins, providing a novel therapeutic strategy for a wide spectrum of diseases. This review delineates detailed synthetic approaches involved in PROTAC building blocks, including the ligand and protein binding parts, linker attached structural components of PROTACs and the actual PROTAC molecules. Furthermore, the recent advancements in PROTAC-mediated degradation of specific oncogenic and other disease-associated proteins, such as those involved in neurodegenerative, antiviral, and autoimmune diseases, were also discussed. Additionally, we described the current landscape of PROTAC clinical trials and highlighted key studies that underscore the translational potential of this emerging therapeutic modality. These findings demonstrate the versatility of PROTACs in modulating the levels of key proteins involved in various severe diseases.

Advances in the study of exosomes in cardiovascular diseases

BACKGROUND

Cardiovascular disease (CVD) has been the leading cause of death worldwide for many years. In recent years, exosomes have gained extensive attention in the cardiovascular system due to their excellent biocompatibility. Studies have extensively researched miRNAs in exosomes and found that they play critical roles in various physiological and pathological processes in the cardiovascular system. These processes include promoting or inhibiting inflammatory responses, promoting angiogenesis, participating in cell proliferation and migration, and promoting pathological progression such as fibrosis.

AIM OF REVIEW

This systematic review examines the role of exosomes in various cardiovascular diseases such as atherosclerosis, myocardial infarction, ischemia-reperfusion injury, heart failure and cardiomyopathy. It also presents the latest treatment and prevention methods utilizing exosomes. The study aims to provide new insights and approaches for preventing and treating cardiovascular diseases by exploring the relationship between exosomes and these conditions. Furthermore, the review emphasizes the potential clinical use of exosomes as biomarkers for diagnosing cardiovascular diseases.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Exosomes are nanoscale vesicles surrounded by lipid bilayers that are secreted by most cells in the body. They are heterogeneous, varying in size and composition, with a diameter typically ranging from 40 to 160 nm. Exosomes serve as a means of information communication between cells, carrying various biologically active substances, including lipids, proteins, and small RNAs such as miRNAs and lncRNAs. As a result, they participate in both physiological and pathological processes within the body.

Pathogen-induced apoptosis in echinoderms: A review

Echinoderms possess unique biological traits that make them valuable models in immunology, regeneration, and developmental biology studies. As a class rich in active substances with significant nutritional and medicinal value, echinoderms face threats from marine pathogens, including bacteria, viruses, fungi, protozoa, and parasites, which have caused substantial economic losses in echinoderm aquaculture. Echinoderms counteract pathogen invasion through innate immunity and programmed cell death, in particular, with apoptosis being essential for eliminating infected or damaged cells and maintaining homeostasis in many echinoderm cell types. Despite the importance of this process, there is a lack of comprehensive and updated reviews on this topic. This review underscores that echinoderm apoptotic pathways exhibit a complexity comparable to that of vertebrates, featuring proteins with unique domains that may indicate the presence of novel signaling mechanisms. We synthesize current knowledge on how echinoderms utilize diverse transcriptional and post-transcriptional mechanisms to regulate apoptosis in response to pathogen infections and explore how pathogens have evolved strategies to manipulate echinoderm apoptosis, either by inhibiting it to create survival niches or by inducing excessive apoptosis to weaken the host. By elucidating the primary apoptotic pathways in echinoderms and the host-pathogen interactions that modulate these pathways, this review aims to reveal new mechanisms of apoptosis in animal immune defense and provide insights into the evolutionary arms race between hosts and pathogens.

Emerging interleukin-1 receptor-associated kinase 4 (IRAK4) inhibitors or degraders as therapeutic agents for autoimmune diseases and cancer

Interleukin-1 receptor-related kinase (IRAK4) is a widely expressed serine/threonine kinase involved in the regulation of innate immunity. IRAK4 plays a pivotal role as a key kinase within the downstream signaling pathway cascades of interleukin-1 receptors (IL-1R) and Toll-like receptors (TLRs). The signaling pathways orchestrated by IRAK4 are integral to inflammatory responses, and its overexpression is implicated in the pathogenesis of inflammatory diseases, autoimmune disorders, and cancer. Consequently, targeting IRAK4-mediated signaling pathways has emerged as a promising therapeutic strategy. Small molecule inhibitors and degraders designed to modulate IRAK4 have shown efficacy in mitigating related diseases. In this paper, we will provide a detailed description of the structure and function of IRAK4, the role of IRAK4 in related diseases, as well as the currently reported small molecule inhibitors and degraders of IRAK4. It is expected to provide new directions for enriching the clinical treatment of inflammation and related diseases.

IRAK2 overexpression restrains prostate cancer progression by regulation of TRAF6 ubiquitination

Prostate cancer is recognized as one of the most common tumors among men worldwide, yet the molecular mechanisms underlying its progression remain to be fully understood. In this study, we explored the role of interleukin-1 receptor-associated kinase 2 (IRAK2) in the progression of prostate cancer. We discovered that IRAK2 expression is downregulated in prostate cancer tissues and cells. Functional assays, including MTT, transwell assays, wound healing assays, and in vivo xenograft models, demonstrated that upregulation of IRAK2 significantly inhibited prostate cancer cell viability, migration, invasion, and tumor growth. Furthermore, we found that IRAK2 modulates the biological functions of prostate cancer by interacting with TNF receptor-associated factor 6 (TRAF6). Knockdown of TRAF6 reversed the suppressive effects of IRAK2 overexpression on prostate cancer cell progression. Additionally, IRAK2 was found to suppress the ubiquitination and degradation of TRAF6 in prostate cancer cells. IRAK2 also influenced the sensitivity of prostate cancer cells to docetaxel (DTX), and silencing IRAK2 reversed the anti-tumor effects of DTX on prostate cancer cells. Our findings suggest that IRAK2 functions as a tumor suppressor in prostate cancer and may serve as a potential therapeutic target for developing effective treatments for prostate cancer.

IRAK-M Plays A Role in the Pathology of Amyotrophic Lateral Sclerosis Through Suppressing the Activation of Microglia

Microglial activation plays a crucial role in the disease progression in amyotrophic lateral sclerosis (ALS). Interleukin receptor-associated kinases-M (IRAK-M) is an important negative regulatory factor in the Toll-like receptor 4 (TLR4) pathway during microglia activation, and its mechanism in this process is still unclear. In the present study, we aimed to investigate the dynamic changes of IRAK-M and its protective effects for motor neurons in SOD1-G93A mouse model of ALS. qPCR (Real-time Quantitative PCR Detecting System) were used to examine the mRNA levels of IRAK-M in the spinal cord in both SOD1-G93A mice and their age-matched wild type (WT) littermates at 60, 100 and 140 days of age. We established an adeno-associated virus 9 (AAV9)-based platform by which IRAK-M was targeted mostly to microglial cells to investigate whether this approach could provide a protection in the SOD1-G93A mouse. Compared with age-matched WT mice, IRAK-M mRNA level was elevated at 100 and 140 days in the anterior horn region of spinal cords in the SOD1-G93A mouse. AAV9-IRAK-M treated SOD1-G93A mice showed reduction of IL-1β mRNA levels and significant improvements in the numbers of spinal motor neurons in spinal cord. Mice also showed previously reduction of muscle atrophy. Our data revealed the dynamic changes of IRAK-M during ALS pathological progression and demonstrated that an AAV9-IRAK-M delivery was an effective and translatable therapeutic approach for ALS. These findings may help identify potential molecular targets for ALS therapy.

Diminished expression of the ubiquitin-proteasome system in early treatment-naïve patients with rheumatoid arthritis and concomitant type 2 diabetes may be linked to IL-1 pathway hyper-activity; results from PEAC cohort

OBJECTIVE

Based on the recent evidence of IL-1 inhibition in patients with rheumatoid arthritis (RA) and concomitant type 2 diabetes (T2D), we evaluated the synovial tissue expression of IL-1 related genes in relationship to the ubiquitin-proteasome system and the effects of insulin on ubiquitinated proteins in fibroblast-like synoviocytes (FLSs).

METHODS

The synovial expression of IL-1 pathway genes was compared in early (< 1 year) treatment-naïve RA patients with T2D (RA/T2D n = 16) and age- and sex-matched RA patients without T2D (n = 16), enrolled in the Pathobiology of Early Arthritis Cohort (PEAC). The synovial expression of ubiquitin in macrophages and synovial lining fibroblasts was also assessed by Immunohistochemistry/immunofluorescence and correlated with synovial pathotypes. Finally, FLSs from RA patients (n = 5) were isolated and treated with human insulin (200 and 500 nM) and ubiquitinated proteins were assessed by western blot.

RESULTS

Synovial tissues of RA/T2D patients were characterised by a consistent reduced expression of ubiquitin-proteasome genes. More specifically, ubiquitin genes (UBB, UBC, and UBA52) and genes codifying proteasome subunits (PSMA2, PSMA6, PSMA7, PSMB1, PSMB3, PSMB4, PSMB6, PSMB8, PSMB9, PSMB10, PSMC1, PSMD9, PSME1, and PSME2) were significantly lower in RA/T2D patients. On the contrary, genes regulating fibroblast functions (FGF7, FGF10, FRS2, FGFR3, and SOS1), and genes linked to IL-1 pathway hyper-activity (APP, IRAK2, and OSMR) were upregulated in RA/T2D. Immunohistochemistry showed a significant reduction of the percentage of ubiquitin-positive cells in synovial tissues of RA/T2D patients. Ubiquitin-positive cells were also increased in patients with a lympho-myeloid pathotype compared to diffuse myeloid or pauci-immune-fibroid. Finally, in vitro experiments showed a reduction of ubiquitinated proteins in RA-FLSs treated with a high concentration of insulin (500 nM).

CONCLUSIONS

A different IL-1 pathway gene expression was observed in the synovial tissues of early treatment-naïve RA/T2D patients, linked to decreased expression of the ubiquitin-proteasome system. These findings may provide a mechanistic explanation of the observed clinical benefits of IL-1 inhibition in patients with RA and concomitant T2D.

Immune Cell Molecular Pharmacodynamics of Lanreotide in Relation to Treatment Response in Patients with Gastroenteropancreatic Neuroendocrine Tumors

The CLARINET trial led to the approval of lanreotide for the treatment of patients with gastroenteropancreatic neuroendocrine tumors (NETs). It is hypothesized that lanreotide regulates proliferation, hormone synthesis, and other cellular functions via binding to somatostatin receptors (SSTR1-5) present in NETs. However, our knowledge of how lanreotide affects the immune system is limited. In vitro studies have investigated functional immune response parameters with lanreotide treatment in healthy donor T cell subsets, encompassing the breadth of SSTR expression, apoptosis induction, cytokine production, and activity of transcription factor signaling pathways. In our study, we characterized in vitro immune mechanisms in healthy donor T cells in response to lanreotide. We also studied the in vivo effects by looking at differential gene expression pre- and post-lanreotide therapy in patients with NET. Immune-focused gene and protein expression profiling was performed on peripheral blood samples from 17 NET patients and correlated with clinical response. In vivo, lanreotide therapy showed reduced effects on wnt, T cell receptor (TCR), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signaling in CD8+ T cells in responders compared to non-responders. Compared to non-responders, responders showed reduced effects on cytokine and chemokine signaling but greater effects on ubiquitination and proteasome degradation genes. Our results suggest significant lanreotide pharmacodynamic effects on immune function in vivo, which correlate with responses in NET patients. This is not evident from experimental in vitro settings.

Methylation of Interleukin-1 receptor-associated kinase-3 and the risk of multiple sclerosis relapse/activity

This study retrospectively investigated the impact of interleukin-1 receptor-associated kinase-3 (IRAK-3/IRAK-M) silencing by methylation on the likelihood of multiple sclerosis (MS) activity. This cross-sectional study included 90 patients with MS: 45 with active disease (Group 1), 45 in remission (Group 2), and 45 healthy controls. The study included quantitation of IRAK-3 methylation index (MI%), IRAK-3 mRNA, and myeloid differentiation factor88 (MyD88) and assessment of NF-κB activity. IRAK-3 MI% was significantly higher in group 1 compared to group 2, accompanied by lower IRAK-3 mRNA expression, elevated circulating MyD88, and increased NF-κB activity. IRAK-3 MI% correlated negatively with its transcript and positively with MyD88 and NF-κB activity. A logistic regression model was created to predict active demyelination. The C-index was 0.924, which indicates a very strong prediction model. Within the limitations of current work, IRAK-3 methylation level seems to be a promising candidate biomarker for identifying MS patients at risk of relapse.

Rabies Virus Regulates Inflammatory Response in BV-2 Cells through Activation of Myd88 and NF-κB Signaling Pathways via TLR7

Rabies is a fatal neurological infectious disease caused by rabies virus (RABV), which invades the central nervous system (CNS). RABV with varying virulence regulates chemokine expression, and the mechanisms of signaling pathway activation remains to be elucidated. The relationship between Toll-like receptors (TLRs) and immune response induced by RABV has not been fully clarified. Here, we investigated the role of TLR7 in the immune response induced by RABV, and one-way analysis of variance (ANOVA) was employed to evaluate the data. We found that different RABV strains (SC16, HN10, CVS-11) significantly increased CCL2, CXCL10 and IL-6 production. Blocking assays indicated that the TLR7 inhibitor reduced the expression of CCL2, CXCL10 and IL-6 (p < 0.01). The activation of the Myd88 pathway in BV-2 cells stimulated by RABV was TLR7-dependent, whereas the inhibition of Myd88 activity reduced the expression of CCL2, CXCL10 and IL-6 (p < 0.01). Meanwhile, the RABV stimulation of BV-2 cells resulted in TRL7-mediated activation of NF-κB and induced the nuclear translocation of NF-κB p65. CCL2, CXCL10 and IL-6 release was attenuated by the specific NF-κB inhibitor used (p < 0.01). The findings above demonstrate that RABV-induced expression of CCL2, CXCL10 and IL-6 involves Myd88 and NF-κB pathways via the TLR7 signal.

Inhibiting the IRAK4/NF-κB/NLRP3 signaling pathway can reduce pyroptosis in hippocampal neurons and seizure episodes in epilepsy

BACKGROUND

Interleukin-1 receptor-associated kinase 4 (IRAK4) plays an important role in immune modulation in various central nervous system disorders. However, IRAK4 has not been reported in epilepsy models in animal and clinical studies, nor has its involvement in regulating pyroptosis in epilepsy.

METHOD

First, we performed transcriptome sequencing, quantitative real-time polymerase chain reaction, and western blot analysis on the hippocampal tissues of refractory epilepsy patients to measure the mRNA and protein levels of IRAK4 and pyroptosis-related proteins. Second, we successfully established a pentylenetetrazol (PTZ)-induced seizure mouse model. We conducted behavioral tests, electroencephalography, virus injection, and molecular biology experiments to investigate the role of IRAK4 in seizure activity regulation.

RESULTS

IRAK4 is upregulated in the hippocampus of epilepsy patients and PTZ-induced seizure model mice. IRAK4 expression is observed in the hilar neurons of PTZ-induced mice. Knocking down IRAK4 in PTZ-induced mice downregulated pyroptosis-related protein expression and alleviated seizure activity. Overexpressing IRAK4 in naive mice upregulated pyroptosis-related protein expression and increased PTZ-induced abnormal neuronal discharges. IRAK4 and NF-κB were found to bind to each other in patient hippocampal tissue samples. Pyrrolidine dithiocarbamate reversed the pyroptosis-related protein expression increase caused by PTZ. PF-06650833 alleviated seizure activity and inhibited pyroptosis in PTZ-induced seizure mice.

CONCLUSION

IRAK4 plays a key role in the pathological process of epilepsy, and its potential mechanism may be related to pyroptosis mediated by the NF-κB/NLRP3 signaling pathway. PF-06650833 has potential as a therapeutic agent for alleviating epilepsy.

IRAK1 deficiency potentiates the efficacy of radiotherapy in repressing cervical cancer development

IRAK1 has been implicated in promoting development of various types of cancers and mediating radioresistance. However, its role in cervical cancer tumorigenesis and radioresistance, as well as the potential underlying mechanisms, remain poorly defined. In this study, we evaluated IRAK1 expression in radiotherapy-treated cervical cancer tissues and found that IRAK1 expression is negatively associated with the efficacy of radiotherapy. Consistently, ionizing radiation (IR)-treated HeLa and SiHa cervical cancer cells express a lower level of IRAK1 than control cells. Depletion of IRAK1 resulted in reduced activation of the NF-κB pathway, decreased cell viability, downregulated colony formation efficiency, cell cycle arrest, increased apoptosis, and impaired migration and invasion in IR-treated cervical cancer cells. Conversely, overexpressing IRAK1 mitigated the anti-cancer effects of IR in cervical cancer cells. Notably, treatment of IRAK1-overexpressing IR-treated HeLa and SiHa cells with the NF-κB pathway inhibitor pyrrolidine dithiocarbamate (PDTC) partially counteracted the effects of excessive IRAK1. Furthermore, our study demonstrated that IRAK1 deficiency enhanced the anti-proliferative role of IR treatment in a xenograft mouse model. These collective observations highlight IRAK1's role in mitigating the anti-cancer effects of radiotherapy, partly through the activation of the NF-κB pathway. SUMMARY: IRAK1 enhances cervical cancer resistance to radiotherapy, with IR treatment reducing IRAK1 expression and increasing cancer cell vulnerability and apoptosis.

Piperine attenuates hepatic ischemia/reperfusion injury via suppressing the TLR4 signaling cascade in mice

Piperine, the major active substance in black pepper, has been shown to have anti-inflammatory and antioxidant effects in several ischemic diseases. However, the role of piperine in hepatic ischemia/reperfusion injury (HIRI) and its underlying mechanisms remain unclear. In this study, the mice were administered piperine (30 mg/kg) intragastric administration before surgery. After 24 h of hepatic ischemia-reperfusion, liver histopathological evaluation, serum transaminase measurements, and TUNEL analysis were performed. The infiltration of inflammatory cells and production of inflammatory mediators in the liver tissue were determined by immunofluorescence and immunohistochemical staining. The protein levels of toll-like receptor 4 (TLR4) and related proteins such as nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukin-1 receptor-associated kinase 1 (IRAK1), p65, and p38 were detected by western blotting. The results showed that plasma aminotransferase (ALT), aspartate aminotransferase (AST), hepatocyte apoptosis, oxidative stress, and inflammatory cell infiltration significantly increased in HIRI mice. Piperine pretreatment notably repaired liver function, improved the histopathology and apoptosis of liver cells, alleviated oxidative stress injury, and reduced inflammatory cell infiltration. Further analysis showed that piperine attenuated tumor necrosis factor-a (TNF-α) and interleukin 6 (IL-6) production and reduced TLR4 activation and phosphorylation of IRAK1, p38, and NF-κB in HIRI. Piperine has a protective effect against HIRI through the TLR4/IRAK1/NF-κB signaling pathway and may be a safer option for future clinical treatment and prevention of ischemia-related diseases.

Research progress of PROTACs for neurodegenerative diseases therapy

Neurodegenerative diseases (NDD) are characterized by the gradual deterioration of neuronal function and integrity, resulting in an overall decline in brain function. The existing therapeutic options for NDD, including Alzheimer's disease, Parkinson's disease, and Huntington's disease, fall short of meeting the clinical demand. A prominent pathological hallmark observed in numerous neurodegenerative disorders is the aggregation and misfolding of proteins both within and outside neurons. These abnormal proteins play a pivotal role in the pathogenesis of neurodegenerative diseases. Targeted degradation of irregular proteins offers a promising avenue for NDD treatment. Proteolysis-targeting chimeras (PROTACs) function via the ubiquitin-proteasome system and have emerged as a novel and efficacious approach in drug discovery. PROTACs can catalytically degrade "undruggable" proteins even at exceptionally low concentrations, allowing for precise quantitative control of aberrant protein levels. In this review, we present a compilation of reported PROTAC structures and their corresponding biological activities aimed at addressing NDD. Spanning from 2016 to present, this review provides an up-to-date overview of PROTAC-based therapeutic interventions. Currently, most protein degraders intended for NDD treatment remain in the preclinical research phase. Overcoming several challenges is imperative, including enhancing oral bioavailability and permeability across the blood-brain barrier, before these compounds can progress to clinical research or eventually reach the market. However, armed with an enhanced comprehension of the underlying pathological mechanisms and the emergence of innovative scaffolds for protein degraders, along with further structural optimization, we are confident that PROTAC possesses the potential to make substantial breakthroughs in the field of neurodegenerative diseases.

Genetic variants in UNC93B1 predispose to childhood-onset systemic lupus erythematosus

Rare genetic variants in toll-like receptor 7 (TLR7) are known to cause lupus in humans and mice. UNC93B1 is a transmembrane protein that regulates TLR7 localization into endosomes. In the present study, we identify two new variants in UNC93B1 (T314A, located proximally to the TLR7 transmembrane domain, and V117L) in a cohort of east Asian patients with childhood-onset systemic lupus erythematosus. The V117L variant was associated with increased expression of type I interferons and NF-κB-dependent cytokines in patient plasma and immortalized B cells. THP-1 cells expressing the variant UNC93B1 alleles exhibited exaggerated responses to stimulation of TLR7/-8, but not TLR3 or TLR9, which could be inhibited by targeting the downstream signaling molecules, IRAK1/-4. Heterozygous mice expressing the orthologous Unc93b1V117L variant developed a spontaneous lupus-like disease that was more severe in homozygotes and again hyperresponsive to TLR7 stimulation. Together, this work formally identifies genetic variants in UNC93B1 that can predispose to childhood-onset systemic lupus erythematosus.

Recent Advances in IRAK1: Pharmacological and Therapeutic Aspects

Interleukin receptor-associated kinase (IRAK) proteins are pivotal in interleukin-1 and Toll-like receptor-mediated signaling pathways. They play essential roles in innate immunity and inflammation. This review analyzes and discusses the physiological functions of IRAK1 and its associated diseases. IRAK1 is involved in a wide range of diseases such as dry eye, which highlights its potential as a therapeutic target under various conditions. Various IRAK1 inhibitors, including Pacritinib and Rosoxacin, show therapeutic potential against malignancies and inflammatory diseases. The covalent IRAK1 inhibitor JH-X-119-01 shows promise in B-cell lymphomas, emphasizing the significance of covalent bonds in its activity. Additionally, the emergence of selective IRAK1 degraders, such as JNJ-101, provides a novel strategy by targeting the scaffolding function of IRAK1. Thus, the evolving landscape of IRAK1-targeted approaches provides promising avenues for increasingly safe and effective therapeutic interventions for various diseases.

Immunogenetics of Systemic Sclerosis

Systemic sclerosis (SSc) is a rare autoimmune connective tissue disorder characterized by massive fibrosis, vascular damage, and immune imbalance. Advances in rheumatology and immunology over the past two decades have led to a redefinition of systemic sclerosis, shifting from its initial perception as primarily a "hyperfibrotic" state towards a recognition of systemic sclerosis as an immune-mediated disease. Consequently, the search for genetic markers has transitioned from focusing on fibrotic mechanisms to exploring immune regulatory pathways. Immunogenetics, an emerging field at the intersection of immunology, molecular biology, and genetics has provided valuable insights into inherited factors that influence immunity. Data from genetic studies conducted thus far indicate that alterations in genetic messages can significantly impact disease risk and progression. While certain genetic variations may confer protective effects, others may exacerbate disease susceptibility. This paper presents a comprehensive review of the most relevant genetic changes that influence both the risk and course of systemic sclerosis. Special emphasis is placed on factors regulating the immune response, recognizing their pivotal role in the pathogenesis of the disease.

Altered X-chromosome inactivation predisposes to autoimmunity

In mammals, males and females show marked differences in immune responses. Males are globally more sensitive to infectious diseases, while females are more susceptible to systemic autoimmunity. X-chromosome inactivation (XCI), the epigenetic mechanism ensuring the silencing of one X in females, may participate in these sex biases. We perturbed the expression of the trigger of XCI, the noncoding RNA Xist, in female mice. This resulted in reactivation of genes on the inactive X, including members of the Toll-like receptor 7 (TLR7) signaling pathway, in monocyte/macrophages and dendritic and B cells. Consequently, female mice spontaneously developed inflammatory signs typical of lupus, including anti-nucleic acid autoantibodies, increased frequencies of age-associated and germinal center B cells, and expansion of monocyte/macrophages and dendritic cells. Mechanistically, TLR7 signaling is dysregulated in macrophages, leading to sustained expression of target genes upon stimulation. These findings provide a direct link between maintenance of XCI and female-biased autoimmune manifestations and highlight altered XCI as a cause of autoimmunity.

MyD88-mediated signaling is critical for the generation of seizure responses and cognitive impairment in a model of anti-N-methyl-D-aspartate receptor encephalitis

OBJECTIVE

We previously demonstrated that interleukin-1 receptor-mediated immune activation contributes to seizure severity and memory loss in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. In the present study, we assessed the role of the myeloid differentiation primary response gene 88 (MyD88), an adaptor protein in Toll-like receptor signaling, in the key phenotypic characteristics of anti-NMDAR encephalitis.

METHODS

Monoclonal anti-NMDAR antibodies or control antibodies were infused into the lateral ventricle of MyD88 knockout mice (MyD88-/-) and control C56BL/6J mice (wild type [WT]) via osmotic minipumps for 2 weeks. Seizure responses were measured by electroencephalography. Upon completion of the infusion, the motor, anxiety, and memory functions of the mice were assessed. Astrocytic (glial fibrillary acidic protein [GFAP]) and microglial (ionized calcium-binding adaptor molecule 1 [Iba-1]) activation and transcriptional activation for the principal inflammatory mediators involved in seizures were determined using immunohistochemistry and quantitative real-time polymerase chain reaction, respectively.

RESULTS

As shown before, 80% of WT mice infused with anti-NMDAR antibodies (n = 10) developed seizures (median = 11, interquartile range [IQR] = 3-25 in 2 weeks). In contrast, only three of 14 MyD88-/- mice (21.4%) had seizures (0, IQR = 0-.25, p = .01). The WT mice treated with antibodies also developed memory loss in the novel object recognition test, whereas such memory deficits were not apparent in MyD88-/- mice treated with anti-NMDAR antibodies (p = .03) or control antibodies (p = .04). Furthermore, in contrast to the WT mice exposed to anti-NMDAR antibodies, the MyD88-/- mice had a significantly lower induction of chemokine (C-C motif) ligand 2 (CCL2) in the hippocampus (p = .0001, Sidak tests). There were no significant changes in the expression of GFAP and Iba-1 in the MyD88-/- mice treated with anti-NMDAR or control antibodies.

SIGNIFICANCE

These findings suggest that MyD88-mediated signaling contributes to the seizure and memory phenotype in anti-NMDAR encephalitis and that CCL2 activation may participate in the expression of these features. The removal of MyD88 inflammation may be protective and therapeutically relevant.

IL-33 Induces Cellular and Exosomal miR-146a Expression as a Feedback Inhibitor of Mast Cell Function

IL-33 is an inflammatory cytokine that promotes allergic disease by activating group 2 innate lymphoid cells, Th2 cells, and mast cells. IL-33 is increased in asthmatics, and its blockade suppresses asthma-like inflammation in mouse models. Homeostatic control of IL-33 signaling is poorly understood. Because the IL-33 receptor, ST2, acts via cascades used by the TLR family, similar feedback mechanisms may exist. MicroRNA (miR)-146a is induced by LPS-mediated TLR4 signaling and serves as a feedback inhibitor. Therefore, we explored whether miR-146a has a role in IL-33 signaling. IL-33 induced cellular and exosomal miR-146a expression in mouse bone marrow-derived mast cells (BMMCs). BMMCs transfected with a miR-146a antagonist or derived from miR-146a knockout mice showed enhanced cytokine expression in response to IL-33, suggesting that miR-146a is a negative regulator of IL-33-ST2 signaling. In vivo, miR-146a expression in plasma exosomes was elevated after i.p. injection of IL-33 in wild-type but not mast cell-deficient KitW-sh/W-sh mice. Finally, KitW-sh/W-sh mice acutely reconstituted with miR-146a knockout BMMCs prior to IL-33 challenge had elevated plasma IL-6 levels compared with littermates receiving wild-type BMMCs. These results support the hypothesis that miR-146a is a feedback regulator of IL-33-mediated mast cell functions associated with allergic disease.

Role of microRNA-146a in cancer development by regulating apoptosis

Despite great advances in diagnostic and treatment options for cancer, like chemotherapy surgery, and radiation therapy it continues to remain a major global health concern. Further research is necessary to find new biomarkers and possible treatment methods for cancer. MicroRNAs (miRNAs), tiny non-coding RNAs found naturally in the body, can influence the activity of several target genes. These genes are often disturbed in diseases like cancer, which perturbs functions like differentiation, cell division, cell cycle, apoptosis and proliferation. MiR-146a is a commonly and widely used miRNA that is often overexpressed in malignant tumors. The expression of miR-146a has been correlated with many pathological and physiological changes in cancer cells, such as the regulation of various cell death paths. It's been established that the control of cell death pathways has a huge influence on cancer progression. To improve our understanding of the interrelationship between miRNAs and cancer cell apoptosis, it's necessary to explore the impact of miRNAs through the alteration in their expression levels. Research has demonstrated that the appearance and spread of cancer can be mitigated by moderating the expression of certain miRNA - a commencement of treatment that presents a hopeful approach in managing cancer. Consequently, it is essential to explore the implications of miR-146a with respect to inducing different forms of tumor cell death, and evaluate its potential to serve as a target for improved chemotherapy outcomes. Through this review, we provide an outline of miR-146a's biogenesis and function, as well as its significant involvement in apoptosis. As well, we investigate the effects of exosomal miR-146a on the promotion of apoptosis in cancer cells and look into how it could possibly help combat chemotherapeutic resistance.

Immunological characterization of stroke-heart syndrome and identification of inflammatory therapeutic targets

Acute cardiac dysfunction caused by stroke-heart syndrome (SHS) is the second leading cause of stroke-related death. The inflammatory response plays a significant role in the pathophysiological process of cardiac damage. However, the mechanisms underlying the brain-heart interaction are poorly understood. Therefore, we aimed to analysis the immunological characterization and identify inflammation therapeutic targets of SHS. We analyzed gene expression data of heart tissue 24 hours after induction of ischemia stoke by MCAO or sham surgery in a publicly available dataset (GSE102558) from Gene Expression Omnibus (GEO). Bioinformatics analysis revealed 138 differentially expressed genes (DEGs) in myocardium of MCAO-treated compared with sham-treated mice, among which, immune and inflammatory pathways were enriched. Analysis of the immune cells infiltration showed that the natural killer cell populations were significantly different between the two groups. We identified five DIREGs, Aplnr, Ccrl2, Cdkn1a, Irak2, and Serpine1 and found that their expression correlated with specific populations of infiltrating immune cells in the cardiac tissue. RT-qPCR and Western blot methods confirmed significant changes in the expression levels of Aplnr, Cdkn1a, Irak2, and Serpine1 after MCAO, which may serve as therapeutic targets to prevent cardiovascular complications after stroke.

Treg cells-derived exosomes promote blood-spinal cord barrier repair and motor function recovery after spinal cord injury by delivering miR-2861

The blood-spinal cord barrier (BSCB) is a physical barrier between the blood and the spinal cord parenchyma. Current evidence suggests that the disruption of BSCB integrity after spinal cord injury can lead to secondary injuries such as spinal cord edema and excessive inflammatory response. Regulatory T (Treg) cells are effective anti-inflammatory cells that can inhibit neuroinflammation after spinal cord injury, and their infiltration after spinal cord injury exhibits the same temporal and spatial characteristics as the automatic repair of BSCB. However, few studies have assessed the relationship between Treg cells and spinal cord injury, emphasizing BSCB integrity. This study explored whether Treg affects the recovery of BSCB after SCI and the underlying mechanism. We confirmed that spinal cord angiogenesis and Treg cell infiltration occurred simultaneously after SCI. Furthermore, we observed significant effects on BSCB repair and motor function in mice by Treg cell knockout and overexpression. Subsequently, we demonstrated the presence and function of exosomes in vitro. In addition, we found that Treg cell-derived exosomes encapsulated miR-2861, and miR-2861 regulated the expression of vascular tight junction (TJs) proteins. The luciferase reporter assay confirmed the negative regulation of IRAK1 by miR-2861, and a series of rescue experiments validated the biological function of IRAKI in regulating BSCB. In summary, we demonstrated that Treg cell-derived exosomes could package and deliver miR-2861 and regulate the expression of IRAK1 to affect BSCB integrity and motor function after SCI in mice, which provides novel insights for functional repair and limiting inflammation after SCI.

Unlocking the potential of PROTACs: A comprehensive review of protein degradation strategies in disease therapy

The technology known asPROTACs (PROteolysisTArgeting Chimeras) is a method of protein degradation. Utilising bifunctional small molecules, the ubiquitin-proteosome system (UPS) is used to induce the ubiquitination and degradation of target proteins. In addition to being novel chemical knockdown agents for biological studies that are catalytic, reversible, and rapid, PROTACs used in the treatment for disorders like cancer, immunological disorders, viral diseases, and neurological disorders. The protein degradation field has advanced quickly over the last two years, with a significant rise in research articles on the subject as well as a quick rise in smallmolecule degraders that are currently in or will soon enter the clinical stage. Other new degrading technologies, in addition to PROTAC and molecular glue technology, are also emerging rapidly. In this review article, we mainly focuses on various PROTAC molecules designed with special emphasis on targeted cellular pathways for different diseases i.e., cancer, Viral diseases Immune disorders, Neurodegenerative diseases, etc. We discussed about new technologies based on PROTACs such as Antibody PROTAC, Aptamers, Dual target, Folate caged, TF PROTAC, etc. Also, we listed out the PROTACs which are in clinical trials.

IRAK-M deficiency exacerbates dopaminergic neuronal damage in a mouse model of sub-acute Parkinson's disease

Emerging evidence has proved that inflammatory responses aggravate the pathological progression of Parkinson's disease. This study aimed to identify the role of Interleukin-1 receptor-associated kinase-M (IRAK-M) as an important negative regulator of innate immunity, in the pathological progression of Parkinson's disease. In the present study, a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) injection was administered to prepare the acute and sub-acute Parkinson's disease mouse models. Western blot analysis was utilized to examine the protein expressions of tyrosine hydroxylase and IRAK-M. The mRNA expression levels of IRAK-M, interleukin (IL)-6, IL-β, and cyclooxygenase-2 were evaluated via using reverse transcription quantitative PCR (RT-qPCR). The expression of tyrosine hydroxylase-positive neurons in corpus striatum and substantia nigra pars compacta (SNc) tissues was detected using immunohistochemistry. The results showed that the protein and mRNA levels of IRAK-M were considerably upregulated in corpus striatum and SNc tissues in the sub-acute Parkinson's disease model. Furthermore, IRAK-M knockout significantly enhanced the MPTP-induced loss of tyrosine hydroxylase-positive fibers in corpus striatum and tyrosine hydroxylase-positive neurons in SNc, and intensified the effect of MPTP on the activation of microglial cells and the expression of inflammatory cytokines. In addition, sub-acute Parkinson's disease mice with IRAK-M deletion exhibited worse motor abilities than those of wild-type littermates. Overall, the present study suggested that IRAK-M reduces dopaminergic neuron damage in sub-acute Parkinson's disease by suppressing inflammation, which may provide a new therapeutic target for Parkinson's disease treatment.

PROTAC Targeted Degradation of IRAK-4 as Potential Treatment in Cancer

Toll-like receptors and interleukin-1 receptor directly interact with intracellular interleukin receptor associated kinase (IRAK) family members to initiate innate immune and inflammatory responses following activation by pathogens. The IRAK family members are involved in linking the innate immune response to the pathogenesis of various diseases, including cancers, non-infectious immune disorders, and metabolic disorders. The Patent Highlight showcases exemplary PROTAC compounds that exhibit a broad range of pharmacological activities associated with degradation of protein targets for the treatment of cancer.

Non-coding RNAs targeting NF-κB pathways in aquatic animals: A review

Nuclear factor-kappa B (NF-κB) pathways have a close relationship with many diseases, especially in terms of the regulation of inflammation and the immune response. Non-coding RNAs (ncRNAs) are a heterogeneous subset of endogenous RNAs that directly affect cellular function in the absence of proteins or peptide products; these include microRNAs (miRNAs), long noncoding RNAs (lncRNAs), circular RNAs (circRNAs), etc. Studies on the roles of ncRNAs in targeting the NF-κB pathways in aquatic animals are scarce. A few research studies have confirmed detailed regulatory mechanisms among ncRNAs and the NF-κB pathways in aquatic animals. This comprehensive review is presented concerning ncRNAs targeting the NF-κB pathway in aquatic animals and provides new insights into NF-κB pathways regulatory mechanisms of aquatic animals. The review discusses new possibilities for developing non-coding-RNA-based antiviral applications in fisheries.

New Insights into the Crosstalk among the Interferon and Inflammatory Signaling Pathways in Response to Viral Infections: Defense or Homeostasis

Innate immunity plays critical roles in eliminating viral infections, healing an injury, and restoring tissue homeostasis. The signaling pathways of innate immunity, including interferons (IFNs), nuclear factor kappa B (NF-κB), and inflammasome responses, are activated upon viral infections. Crosstalk and interplay among signaling pathways are involved in the complex regulation of antiviral activity and homeostasis. To date, accumulating evidence has demonstrated that NF-κB or inflammasome signaling exhibits regulatory effects on IFN signaling. In addition, several adaptors participate in the crosstalk between IFNs and the inflammatory response. Furthermore, the key adaptors in innate immune signaling pathways or the downstream cytokines can modulate the activation of other signaling pathways, leading to excessive inflammatory responses or insufficient antiviral effects, which further results in tissue injury. This review focuses on the crosstalk between IFN and inflammatory signaling to regulate defense and homeostasis. A deeper understanding of the functional aspects of the crosstalk of innate immunity facilitates the development of targeted treatments for imbalanced homeostasis.

Role of protein phosphorylation in cell signaling, disease, and the intervention therapy

Protein phosphorylation is an important post-transcriptional modification involving an extremely wide range of intracellular signaling transduction pathways, making it an important therapeutic target for disease intervention. At present, numerous drugs targeting protein phosphorylation have been developed for the treatment of various diseases including malignant tumors, neurological diseases, infectious diseases, and immune diseases. In this review article, we analyzed 303 small-molecule protein phosphorylation kinase inhibitors (PKIs) registered and participated in clinical research obtained in a database named Protein Kinase Inhibitor Database (PKIDB), including 68 drugs approved by the Food and Drug Administration of the United States. Based on previous classifications of kinases, we divided these human protein phosphorylation kinases into eight groups and nearly 50 families, and delineated their main regulatory pathways, upstream and downstream targets. These groups include: protein kinase A, G, and C (AGC) and receptor guanylate cyclase (RGC) group, calmodulin-dependent protein kinase (CaMK) group, CMGC [Cyclin-dependent kinases (CDKs), Mitogen-activated protein kinases (MAPKs), Glycogen synthase kinases (GSKs), and Cdc2-like kinases (CLKs)] group, sterile (STE)-MAPKs group, tyrosine kinases (TK) group, tyrosine kinase-like (TKL) group, atypical group, and other groups. Different groups and families of inhibitors stimulate or inhibit others, forming an intricate molecular signaling regulatory network. This review takes newly developed new PKIs as breakthrough point, aiming to clarify the regulatory network and relationship of each pathway, as well as their roles in disease intervention, and provide a direction for future drug development.

MiR-146b-5p regulates IL-23 receptor complex expression in chronic lymphocytic leukemia cells

Chronic lymphocytic leukemia (CLL) cells express the interleukin-23 receptor (IL-23R) chain, but the expression of the complementary IL-12Rβ1 chain requires cell stimulation via surface CD40 molecules (and not via the B-cell receptor [BCR]). This stimulation induces the expression of a heterodimeric functional IL-23R complex and the secretion of IL-23, initiating an autocrine loop that drives leukemic cell expansion. Based on the observation in 224 untreated Binet stage A patients that the cases with the lowest miR-146b-5p concentrations had the shortest time to first treatment (TTFT), we hypothesized that miR-146b-5p could negatively regulate IL-12Rβ1 side chain expression and clonal expansion. Indeed, miR-146b-5p significantly bound to the 3'-UTR region of the IL-12Rβ1 mRNA in an in vitro luciferase assay. Downregulation of miR-146b-5p with specific miRNA inhibitors in vitro led to the upregulation of the IL-12Rβ1 side chain and expression of a functional IL-23R complex similar to that observed after stimulation of the CLL cell through the surface CD40 molecules. Expression of miR-146b-5p with miRNA mimics in vitro inhibited the expression of the IL-23R complex after stimulation with CD40L. Administration of a miR-146b-5p mimic to NSG mice, successfully engrafted with CLL cells, caused tumor shrinkage, with a reduction of leukemic nodules and of IL-12Rβ1-positive CLL cells in the spleen. Our findings indicate that IL-12Rβ1 expression, a crucial checkpoint for the functioning of the IL-23 and IL-23R complex loop, is under the control of miR-146b-5p, which may represent a potential target for therapy since it contributes to the CLL pathogenesis. This trial is registered at www.clinicaltrials.gov as NCT00917540.

Recent Advances in PROTACs for Drug Targeted Protein Research

Proteolysis-targeting chimera (PROTAC) is a heterobifunctional molecule. Typically, PROTAC consists of two terminals which are the ligand of the protein of interest (POI) and the specific ligand of E3 ubiquitin ligase, respectively, via a suitable linker. PROTAC degradation of the target protein is performed through the ubiquitin–proteasome system (UPS). The general process is that PROTAC binds to the target protein and E3 ligase to form a ternary complex and label the target protein with ubiquitination. The ubiquitinated protein is recognized and degraded by the proteasome in the cell. At present, PROTAC, as a new type of drug, has been developed to degrade a variety of cancer target proteins and other disease target proteins, and has shown good curative effects on a variety of diseases. For example, PROTACs targeting AR, BR, BTK, Tau, IRAK4, and other proteins have shown unprecedented clinical efficacy in cancers, neurodegenerative diseases, inflammations, and other fields. Recently, PROTAC has entered a phase of rapid development, opening a new field for biomedical research and development. This paper reviews the various fields of targeted protein degradation by PROTAC in recent years and summarizes and prospects the hot targets and indications of PROTAC.

Plasma exosomal IRAK1 can be a potential biomarker for predicting the treatment response to renin-angiotensin system inhibitors in patients with IgA nephropathy

Background

Renin-angiotensin system inhibitors (RASi) are the first choice and basic therapy for the treatment of IgA nephropathy (IgAN) with proteinuria. However, approximately 40% of patients have no response to RASi treatment. The aim of this study was to screen potential biomarkers for predicting the treatment response of RASi in patients with IgAN.

Methods

We included IgAN patients who were treatment-naive. They received supportive treatment, including a maximum tolerant dose of RASi for 3 months. According to the degree of decrease in proteinuria after 3 months of follow-up, these patients were divided into a sensitive group and a resistant group. The plasma of the two groups of patients was collected, and the exosomes were extracted for high-throughput sequencing. The screening of hub genes was performed using a weighted gene co-expression network (WGCNA) and filtering differentially expressed genes (DEGs). We randomly selected 20 patients in the sensitive group and 20 patients in the resistant group for hub gene validation by real-time quantitative polymerase chain reaction (qRT−PCR). A receiver operating characteristic (ROC) curve was used to evaluate hub genes that predicted the efficacy of the RASi response among the 40 validation patients.

Results

After screening 370 IgAN patients according to the inclusion and exclusion criteria and the RASi treatment response evaluation, there were 38 patients in the sensitive group and 32 patients in the resistant group. IRAK1, ABCD1 and PLXNB3 were identified as hub genes by analyzing the high-throughput sequencing of the plasma exosomes of the two groups through WGCNA and DEGs screening. The sequencing data were consistent with the validation data showing that these three hub genes were upregulated in the resistant group compared with the sensitive group. The ROC curve indicated that IRAK1 was a good biomarker to predict the therapeutic response of RASi in patients with IgAN.

Conclusions

Plasma exosomal IRAK1 can be a potential biomarker for predicting the treatment response of RASi in patients with IgAN.

Changes in plasma IRAK-M in patients with prediabetes and its relationship with related metabolic indexes: a cross-sectional study

OBJECTIVE

To investigate whether IL-1R-associated kinase (IRAK)-M is associated with prediabetes and type 2 diabetes (T2D).

METHODS

In this cross-sectional study, enrolled subjects were assigned to different groups according to their fasting plasma glucose (FPG) values. IRAK-M and metabolic parameters, including fasting insulin (FINS), glycosylated hemoglobin (HbA1c), homeostasis model assessment of insulin resistance (HOMA-IR) and beta-cell function (HOMA-β), and thioredoxin-interacting protein (TXNIP), were evaluated. The area under the receiver operating characteristic curve of IRAK-M and TXNIP for prediabetes and T2D was determined.

RESULTS

IRAK-M decreased significantly with increasing FPG levels. IRAK-M was negatively correlated with TXNIP, FPG, FINS, HbA1c, and HOMA-IR and positively correlated with HOMA-β. The diagnostic cutoff value of IRAK-M was 3.76 ng/mL for prediabetes and 3.45 ng/mL for T2D. After stratifying by IRAK-M (<3.76 and ≥3.76 ng/mL), patients with a higher TXNIP level showed a greater risk of prediabetes or T2D in the subgroup with low IRAK-M (<3.76 ng/mL).

CONCLUSIONS

IRAK-M is independently and positively associated with prediabetes and T2D, while TXNIP is independently and negatively associated with prediabetes and T2D. IRAK-M and TXNIP serve as diagnostic factors for prediabetes.

Nonhematopoietic IRAK1 drives arthritis via neutrophil chemoattractants

IL-1 receptor-activated kinase 1 (IRAK1) is involved in signal transduction downstream of many TLRs and the IL-1R. Its potential as a drug target for chronic inflammatory diseases is underappreciated. To study its functional role in joint inflammation, we generated a mouse model expressing a functionally inactive IRAK1 (IRAK1 kinase deficient, IRAK1KD), which also displayed reduced IRAK1 protein expression and cell type–specific deficiencies of TLR signaling. The serum transfer model of arthritis revealed a potentially novel role of IRAK1 for disease development and neutrophil chemoattraction exclusively via its activity in nonhematopoietic cells. Consistently, IRAK1KD synovial fibroblasts showed reduced secretion of neutrophil chemoattractant chemokines following stimulation with IL-1β or human synovial fluids from patients with rheumatoid arthritis (RA) and gout. Together with patients with RA showing prominent IRAK1 expression in fibroblasts of the synovial lining, these data suggest that targeting IRAK1 may be therapeutically beneficial. As pharmacological inhibition of IRAK1 kinase activity had only mild effects on synovial fibroblasts from mice and patients with RA, targeted degradation of IRAK1 may be the preferred pharmacologic modality. Collectively, these data position IRAK1 as a central regulator of the IL-1β–dependent local inflammatory milieu of the joints and a potential therapeutic target for inflammatory arthritis.

Tongxinluo-pretreated mesenchymal stem cells facilitate cardiac repair via exosomal transfer of miR-146a-5p targeting IRAK1/NF-κB p65 pathway

Background

Bone marrow cells (BMCs), especially mesenchymal stem cells (MSCs), have shown attractive application prospects in acute myocardial infarction (AMI). However, the weak efficacy becomes their main limitation in clinical translation. Based on the anti-inflammation and anti-apoptosis effects of a Chinese medicine-Tongxinluo (TXL), we aimed to explore the effects of TXL-pretreated MSCs (MSCs^TXL) in enhancing cardiac repair and further investigated the underlying mechanism.

Methods

MSCs^TXL or MSCs and the derived exosomes (MSCs^TXL-exo or MSCs-exo) were collected and injected into the infarct zone of rat hearts. In vivo, the anti-apoptotic and anti-inflammation effects, and cardiac functional and histological recovery were evaluated. In vitro, the apoptosis was evaluated by western blotting and flow cytometry. miRNA sequencing was utilized to identify the significant differentially expressed miRNAs between MSCs^TXL-exo and MSCs-exo, and the miRNA mimics and inhibitors were applied to explore the specific mechanism.

Results

Compared to MSCs, MSCs^TXL enhanced cardiac repair with reduced cardiomyocytes apoptosis and inflammation at the early stage of AMI and significantly improved left ventricular ejection fraction (LVEF) with reduced infarct size in an exosome-dependent way. Similarly, MSCs^TXL-exo exerted superior therapeutic effects in anti-apoptosis and anti-inflammation, as well as improving LVEF and reducing infarct size compared to MSCs-exo. Further exosomal miRNA analysis demonstrated that miR-146a-5p was the candidate effector of the superior effects of MSCs^TXL-exo. Besides, miR-146a-5p targeted and decreased IRAK1, which inhibited the nuclear translocation of NF-κB p65 thus protecting H9C2 cells from hypoxia injury.

Conclusions

This study suggested that MSCs^TXL markedly facilitated cardiac repair via a new mechanism of the exosomal transfer of miR-146a-5p targeting IRAK1/NF-κB p65 pathway, which has great potential for clinical translation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02969-y.

Allicin attenuated hepatic ischemia/reperfusion injury in mice by regulating PPARγ-IRAK-M-TLR4 signal pathway

Background: Hepatic ischemia/reperfusion (I/R) injury to the liver is a significant cause of morbidity and mortality following liver surgery, trauma, and hemorrhagic shock. It was reported that allicin, a type of garlic compound, had a protective effect against other hepatic diseases. Allicin's ability to protect against liver injury caused by ischemic reperfusion remains unknown. As a result, we conducted this study to determine allicin's effects and mechanism of action in hepatic I/R injury. Method: The liver I/R injury model was established by clamping the blood supply to the left and middle liver lobes. Three days prior to the hepatic I/R injury, different concentrations of allicin were gavaged. Then, hepatic function, histological changes, apoptosis markers, oxidative stress, and inflammatory cytokines were measured, and the molecular mechanisms were evaluated using western blot. Another separation experiment used IRAK-M knockout mice and peroxisome proliferator-activated receptor-gamma (PPARγ) inhibitor to deduce the molecular mechanisms. Results: Pretreatment with allicin prior to hepatic I/R injury reduced liver damage by inhibiting aminotransferase activity and alleviating liver injury. It significantly decreased cell apoptosis, interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) production, and hepatic oxidative stress. Furthermore, this study demonstrated that GW9662 (inhibitor of PPARγ) abrogated allicin's positive effect by inhibiting PPARγ expression while suppressing IRAK-M expression. Thus, the depletion of IRAK-M cannot influence the expression of PPARγ. The down-regulation of PPARγ-IRAK-M disabled the protection of allicin in I/R injury. Conclusion: Allicin protects against hepatic I/R injury via dose-dependent regulation of the PPARγ-IRAK-M-TLR4 signaling pathway, and it may be a potential drug in future clinical treatment.

PROTACs: great opportunities for academia and industry (an update from 2020 to 2021)

PROteolysis TArgeting Chimeras (PROTACs) technology is a new protein-degradation strategy that has emerged in recent years. It uses bifunctional small molecules to induce the ubiquitination and degradation of target proteins through the ubiquitin-proteasome system. PROTACs can not only be used as potential clinical treatments for diseases such as cancer, immune disorders, viral infections, and neurodegenerative diseases, but also provide unique chemical knockdown tools for biological research in a catalytic, reversible, and rapid manner. In 2019, our group published a review article "PROTACs: great opportunities for academia and industry" in the journal, summarizing the representative compounds of PROTACs reported before the end of 2019. In the past 2 years, the entire field of protein degradation has experienced rapid development, including not only a large increase in the number of research papers on protein-degradation technology but also a rapid increase in the number of small-molecule degraders that have entered the clinical and will enter the clinical stage. In addition to PROTAC and molecular glue technology, other new degradation technologies are also developing rapidly. In this article, we mainly summarize and review the representative PROTACs of related targets published in 2020-2021 to present to researchers the exciting developments in the field of protein degradation. The problems that need to be solved in this field will also be briefly introduced.

A Pan-Cancer Analysis of IRAK1 Expression and Their Association With Immunotherapy Response

IRAK1 is an active kinase which plays a critical role in IL-1/TLR signaling pathway involved in inflammation and innate immune response. Recently, increasing evidence supports a potential role of IRAK1 in cancer progression. However, no immunological pan-cancer analysis of IRAK1 is available. We aimed to explore the prognostic value and the immunological functions of IRAK1. A series of datasets including The Cancer Genome Atlas, GEPIA2, cBioPortal, HPA, TIMER2.0 were performed to explore the oncogenic and immunological roles of IRAK1, including the relationship between IRAK1 and prognosis, genetic mutation, GO and KEGG enrichment pathway analysis, immune state of different tumors, The results showed that IRAK1 levels were upregulated in more than 20 types of cancers compared to the normal tissues. IRAK1 expression was associated with poorer prognosis in different cancer types. For the most frequent DNA alteration of IRAK1 is amplification. And the result of the enrichment analysis suggested that IRAK1 related to immune checkpoint pathway in cancer. IRAK1 inhibitor pacritinib inhibit proliferation and upregulate PD-L1 expression in different cancer cell lines. Moreover, the patients who receiving anti-PD-L1 therapy with low IRAK1 expression had a better prognosis, and the objective response rate to anti-PD-L1 therapy was higher in the low IRAK1 group than in the high IRAK1 group in IMvigor210 cohort. Our study reveals that IRAK1 can function as a prognostic marker in various malignant tumors. And pacritinib upregulated PD-L1 expression in several cancer cell lines, which indicating that IRAK1 can be used as a reliable marker to predict the efficacy of immunotherapy.

Albiflorin Alleviates Ox-LDL-Induced Human Umbilical Vein Endothelial Cell Injury through IRAK1/TAK1 Pathway

Introduction

Atherosclerosis (AS) is a chronic inflammatory disease characterized by lipid metabolism disorder and vascular endothelial damage. Albiflorin (AF) has been certified to be effective in the therapy of certain inflammatory diseases, while the therapeutic effect and mechanism of AF on AS have not been fully elucidated. Material and Methods. Model cells for AS were created by inducing oxidized low-density lipoprotein (Ox-LDL) in human umbilical vein endothelial cells (HUVECs). After processing with AF and interleukin-1 receptor-associated kinase 1- (IRAK1-) overexpressed plasmid, cell viability was assessed by CCK-8; cholesterol efflux was tested using liquid scintillation counter; IL-6 and TNF-α levels were determined with ELISA kits; ROS and apoptosis were confirmed using Flow cytometry. Besides, IRAK1-TAK1 pathway and apoptosis- and mitochondrial fusion-related proteins were monitored with western blotting analysis.

Results

Our results verified that AF could not only dramatically accelerate viability and cholesterol efflux but also attenuate inflammation, ROS production, and apoptosis in Ox-LDL-induced HUVECs. Meanwhile, AF could prominently prevent the activation of IRAK1-TAK1 pathway, downregulate apoptosis-related proteins, and upregulate mitochondrial fusion-related proteins in Ox-LDL-induced HUVECs. Moreover, we testified that IRAK1 overexpression memorably could reverse suppression of AF on inflammation, apoptosis, and IRAK1-TAK1 pathway and enhancement of AF on viability, cholesterol efflux, and mitochondrial fusion in Ox-LDL-induced HUVECs.

Conclusions

By blocking the IRAK1/TAK1 pathway, AF can significantly slow the course of AS, suggesting that it could be a viable therapeutic option for AS.

Qishen Granule (QSG) Inhibits Monocytes Released From the Spleen and Protect Myocardial Function via the TLR4-MyD88-NF-κB p65 Pathway in Heart Failure Mice

Preliminary clinical and basic researches have proved that Qishen granule (QSG) is an effective prescription for treating heart failure (HF) in China, with a characteristic of regulating the ratio of M1/M2 macrophage in the myocardium. However, the regulative mechanism of monocytes targeting the cardio-splenic axis has not been fully elucidated. This study aimed to investigate the effects and mechanism of QSG inhibiting the release of splenic monocytes and the recruitment of myocardial tissue both in vivo and in vitro. Experiments in mice with acute myocardial infarction (AMI)-induced HF demonstrated that QSG could exert anti-inflammatory effects by inhibiting splenic monocytes release and phenotypic changes. Moreover, in vitro experiments indicated QSG could inhibit LPS-stimulated macrophage-conditioned medium (CM)-induced H9C2 cardiomyocyte injury by upregulating the key proteins in TLR4-MyD88-NF-κB p65 pathway. In addition, knockdown or overexpression of TLR4 in H9C2 cells further confirmed that QSG could attenuate inflammatory injury in cardiomyocytes via the TLR4-MyD88-NF-κB p65 pathway. Overall, these data suggested that QSG could improve cardiac function and reduce the inflammatory response in AMI-induced HF by inhibiting splenic monocytes release, and protecting myocardial function via the TLR4-MyD88-NF-κB pathway in heart failure mice.

IRAK4 exacerbates traumatic brain injury via activation of TAK1 signaling pathway

Although multiple signaling pathways contributing to the pathophysiological process have been investigated, treatments for traumatic brain injury (TBI) against present targets have not acquired significant clinical progress. Interleukin-1 receptor-associated kinase 4 (IRAK4) is an important factor involved in regulating immunity and inflammation. However, the role of IRAK4 in TBI still remains largely unknown. Therefore, using a controlled cortical impact model (CCI), we investigated the function and molecular mechanism of IRAK4 in the context of TBI. IRAK4 was found to be activated in a time-dependent manner after TBI and mainly expressed in neurons. Inhibition of IRAK4 by siRNAs could significantly alleviates neuroinflammation, neuron apoptosis, brain edema, brain-blood barrier (BBB) dysfunction and improves neurological deficit in the context of CCI. Mechanistically, IRAK4 exacerbates CCI via activation of TAK1 signaling pathway. Interestingly, PF-0665083, an IRAK4 inhibitor, inhibits phosphorylation of IRAK4 and attenuates CCI-induced secondary injury. It could be conclude that IRAK4 plays a critical role in TBI-induced secondary injury and the underlining mechanism may be related to activation of TAK1 signaling pathway. PF-0665083 may serve as a potential treatment strategy to relieve TBI.

Targeting the Non-Catalytic Functions: a New Paradigm for Kinase Drug Discovery?

Protein kinases have been highly fruitful targets for cancer drug discovery in the past two decades, while most of these drugs bind to the "adenosine triphosphate (ATP)-site" and inhibit kinase catalytic activity. Recently, accumulated evidence suggests that kinases possess functions beyond catalysis through their scaffolds, and the scaffolding functions could play critical roles in multiple cellular signaling and cell fate controls. Small molecules modulating the noncatalytic functions of kinases are rarely reported but emerge as new promising therapeutic strategies for various diseases. Herein, we summarize the characterized noncatalytic functions of kinases, and highlight the recent progress on developing small-molecule modulators of the noncatalytic functions of kinases. Mechanisms and characteristics of different kinds of modulators are also discussed. It is also speculated that targeting the noncatalytic functions would represent a new direction for kinase-based drug discovery.