• Journal of Ginseng Research
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• v.47 no.6
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• pp.706-713
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• 2023

Background and objective: The ability to inhibit aggregation has been demonstrated with synthetically derived ginsenoside compounds G-Rp (1, 3, and 4) and ginsenosides naturally found in Panax ginseng 20(S)-Rg3, Rg6, F4, and Ro. Among these compounds, Rk3 (G-Rk3) from Panax ginseng needs to be further explored in order to reveal the mechanisms of action during inhibition. Methodology: Our study focused to investigate the action of G-Rk3 on agonist-stimulated human platelet aggregation, inhibition of platelet signaling molecules such as fibrinogen binding with integrin α_IIbβ₃ using flow cytometry, intracellular calcium mobilization, dense granule secretion, and thromboxane B₂ secretion. In addition, we checked the regulation of phosphorylation on PI3K/MAPK pathway, and thrombin-induced clot retraction was also observed in platelets rich plasma. Key Results: G-Rk3 significantly increased amounts of cyclic adenosine monophosphate (cAMP) and led to significant phosphorylation of cAMP-dependent kinase substrates vasodilator-stimulated phosphoprotein (VASP) and inositol 1,4,5-trisphosphate receptor (IP₃R). In the presence of G-Rk3, dense tubular system Ca²⁺ was inhibited, and platelet activity was lowered by inactivating the integrin αIIb/β₃ and reducing the binding of fibrinogen. Furthermore, the effect of G-Rk3 extended to the inhibition of MAPK and PI3K/Akt phosphorylation resulting in the reduced secretion of intracellular granules and reduced production of TXA₂. Lastly, G-Rk3 inhibited platelet aggregation and thrombus formation via fibrin clot. Conclusions and implications: These results suggest that when dealing with cardiovascular diseases brought upon by faulty aggregation among platelets or through the formation of a thrombus, the G-Rk3 compound can play a role as an effective prophylactic or therapeutic agent.

• Molecules and Cells
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• v.46 no.10
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• pp.579-588
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• 2023

Sarcomas are rare and heterogeneous mesenchymal neoplasms originating from the bone or soft tissues, which pose significant treatment challenges. The current standard treatment for sarcomas consists of surgical resection, often combined with chemo- and radiotherapy; however, local recurrence and metastasis remain significant concerns. Although immunotherapy has demonstrated promise in improving long-term survival rates for certain cancers, sarcomas are generally considered to be relatively less immunogenic than other tumors, presenting substantial challenges for effective immunotherapy. In this review, we examine the possible opportunities for sarcoma immunotherapy, noting cancer testis antigens expressed in sarcomas. We then cover the current status of immunotherapies in sarcomas, including progress in cancer vaccines, immune checkpoint inhibitors, and adoptive cellular therapy and their potential in combating these tumors. Furthermore, we discuss the limitations of immunotherapies in sarcomas, including a low tumor mutation burden and immunosuppressive tumor microenvironment, and explore potential strategies to tackle the immunosuppressive barriers in therapeutic interventions, shedding light on the development of effective and personalized treatments for sarcomas. Overall, this review provides a comprehensive overview of the current status and potential of immunotherapies in sarcoma treatment, highlighting the challenges and opportunities for developing effective therapies to improve the outcomes of patients with these rare malignancies.

• BMB Reports
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• v.57 no.5
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• pp.207-215
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• 2024

The gut microbiota, an intricate community of bacteria residing in the gastrointestinal system, assumes a pivotal role in various physiological processes. Beyond its function in food breakdown and nutrient absorption, gut microbiota exerts a profound influence on immune and metabolic modulation by producing diverse gut microbiota-generated metabolites (GMGMs). These small molecules hold potential to impact host health via multiple pathways, which exhibit remarkable diversity, and have gained increasing attention in recent studies. Here, we elucidate the intricate implications and significant impacts of four specific metabolites, Urolithin A (UA), equol, Trimethylamine N-oxide (TMAO), and imidazole propionate, in shaping human health. Meanwhile, we also look into the advanced research on GMGMs, which demonstrate promising curative effects and hold great potential for further clinical therapies. Notably, the emergence of positive outcomes from clinical trials involving GMGMs, typified by UA, emphasizes their promising prospects in the pursuit of improved health and longevity. Collectively, the multifaceted impacts of GMGMs present intriguing avenues for future research and therapeutic interventions.

• IMMUNE NETWORK
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• v.24 no.1
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• pp.10.1-10.17
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• 2024

In this review, we will explore the intricate roles of cytokines and vascular endothelial growth factors in autoimmune diseases (ADs), with a particular focus on rheumatoid arthritis (RA) and multiple sclerosis (MS). AD is characterized by self-destructive immune responses due to auto-reactive T lymphocytes and Abs. Among various types of ADs, RA and MS possess inflammation as a central role but in different sites of the patients. Other common aspects among these two ADs are their chronicity and relapsing-remitting symptoms requiring continuous management. First factor inducing these ADs are cytokines, such as IL-6, TNF-α, and IL-17, which play significant roles in the pathogenesis by contributing to inflammation, immune cell activation, and tissue damage. Secondly, vascular endothelial growth factors, including VEGF and angiopoietins, are crucial in promoting angiogenesis and inflammation in these two ADs. Finally, placental growth factor (PlGF), an emerging factor with bi-directional roles in angiogenesis and T cell differentiation, as we introduce as an "angio-lymphokine" is another key factor in ADs. Thus, while angiogenesis recruits more inflammatory cells into the peripheral sites, cytokines secreted by effector cells play critical roles in the pathogenesis of ADs. Various therapeutic interventions targeting these soluble molecules have shown promise in managing autoimmune pathogenic conditions. However, delicate interplay between cytokines, angiogenic factors, and PlGF has more to be studied when considering their complementary role in actual pathogenic conditions. Understanding the complex interactions among these factors provides valuable insights for the development of innovative therapies for RA and MS, offering hope for improved patient outcomes.

• Molecules and Cells
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• v.47 no.1
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• pp.100005.1-100005.15
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• 2024

Amyotrophic lateral sclerosis is a devastating neurodegenerative disease with a complex genetic basis, presenting both in familial and sporadic forms. The hexanucleotide (G₄C₂) repeat expansion in the C9orf72 gene, which triggers distinct pathogenic mechanisms, has been identified as a major contributor to familial and sporadic Amyotrophic lateral sclerosis cases. Animal models have proven pivotal in understanding these mechanisms; however, discrepancies between models due to variable transgene sequence, expression levels, and toxicity profiles complicate the translation of findings. Herein, we provide a systematic comparison of 7 publicly available Drosophila transgenes modeling the G₄C₂ expansion under uniform conditions, evaluating variations in their toxicity profiles. Further, we tested 3 previously characterized disease-modifying drugs in selected lines to uncover discrepancies among the tested strains. Our study not only deepens our understanding of the C9orf72 G₄C₂ mutations but also presents a framework for comparing constructs with minute structural differences. This work may be used to inform experimental designs to better model disease mechanisms and help guide the development of targeted interventions for neurodegenerative diseases, thus bridging the gap between model-based research and therapeutic application.

• Molecules and Cells
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• v.46 no.11
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• pp.700-709
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• 2023

Mucus hyperproduction and hypersecretion are observed often in respiratory diseases. MUC8 is a glycoprotein synthesized by epithelial cells and generally expressed in the respiratory track. However, the physiological mechanism by which extracellular nucleotides induce MUC8 gene expression in human airway epithelial cells is unclear. Here, we show that UTP could induce MUC8 gene expression through P2Y2-PLCβ3-Ca²⁺ activation. Because the full-length cDNA sequence of MUC8 has not been identified, a specific siRNA-MUC8 was designed based on the partial cDNA sequence of MUC8. siRNA-MUC8 significantly increased TNF-α production and decreased IL-1Ra production, suggesting that MUC8 may downregulate UTP/P2Y2-induced airway inflammation. Interestingly, the PDZ peptide of ZO-1 protein strongly abolished UTP-induced TNF-α production and increased IL-1Ra production and MUC8 gene expression. In addition, the PDZ peptide dramatically increased the levels of UTP-induced ZO proteins and TEER (trans-epithelial electrical resistance). These results show that the anti-inflammatory mucin MUC8 may contribute to homeostasis, and the PDZ peptide can be a novel therapeutic candidate for UTP-induced airway inflammation.

• IMMUNE NETWORK
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• v.24 no.3
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• pp.21.1-21.16
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• 2024

IL-1, a pleiotropic cytokine with profound effects on various cell types, particularly immune cells, plays a pivotal role in immune responses. The proinflammatory nature of IL-1 necessitates stringent control mechanisms of IL-1-mediated signaling at multiple levels, encompassing transcriptional and translational regulation, precursor processing, as well as the involvement of a receptor accessory protein, a decoy receptor, and a receptor antagonist. In T-cell immunity, IL-1 signaling is crucial during both the priming and effector phases of immune reactions. The fine-tuning of IL-1 signaling hinges upon two distinct receptor types; the functional IL-1 receptor (IL-1R) 1 and the decoy IL-1R2, accompanied by ancillary molecules such as the IL-1R accessory protein (IL-1R3) and IL-1R antagonist. IL-1R1 signaling by IL-1β is critical for the differentiation, expansion, and survival of Th17 cells, essential for defense against extracellular bacteria or fungi, yet implicated in autoimmune disease pathogenesis. Recent investigations emphasize the physiological importance of IL-1R2 expression, particularly in its capacity to modulate IL-1-dependent responses within Tregs. The precise regulation of IL-1R signaling is indispensable for orchestrating appropriate immune responses, as unchecked IL-1 signaling has been implicated in inflammatory disorders, including Th17-mediated autoimmunity. This review provides a thorough exploration of the IL-1R signaling complex and its pivotal roles in immune regulation. Additionally, it highlights recent advancements elucidating the mechanisms governing the expression of IL-1R1 and IL-1R2, underscoring their contributions to fine-tuning IL-1 signaling. Finally, the review briefly touches upon therapeutic strategies targeting IL-1R signaling, with potential clinical applications.

• Radiation Oncology Journal
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• v.17 no.4
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• pp.307-313
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• 1999

Purpose : To investigate the Presence of adaptive response by low dose radiation in murine tumors in relation to radiation induced apoptosis as well as related mechanism. Materials and Methods : Syngeneic murine tumors, OCa-I and HCa-l, were given 0.05 Gy pretreatment followed by therapeutic dose of 25 Gy radiation. Induction of apoptosis was analyzed for each treatment group. Regulating molecules of apoptosis, p53, Bcl-2, Bax, Bcl-X, were also analyzed by Western blotting. Results : In 0.05 Gy pretreatment group of OCa-I, 25 Gy-induced apoptosis per 1000 cells was 229, which was estimated at $30\%$ lower level than the expected (p<0.05). In contrast, this reduction in radiation induced apoptosis was not seen in HCa-l. In the expression of apoptosis regulating molecules, p53 increased in both tumors in response to radiation. Bcl-2 and Bax did not show significant change in both tumors however, the expression of Bcl-2 surpassed that of Bax in 0.05 Gy pretreatment group of OCa-l. Bcl-X was not expressed in OCa-l. In HCa-l, Bcl-X showed increased expression even with 0.05 Gy. Conclusion : Adaptive response by low dose radiation Is shown in one murine tumor, OCa-l, in relation to radiation induced apoptosis. Apoptosis regulating molecules including Bcl-2/Bax and Bcl-X, appear to related. This study shows an evidence that adaptive response is present, but not a generalized phenomenon in vivo.

• Molecules and Cells
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• v.26 no.5
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• pp.468-473
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• 2008

Low-density lipoprotein (LDL) induces cell proliferation in human aortic smooth muscle cells (hAoSMCs), which may be involved in atherogenesis and intimal hyperplasia. Recent studies have demonstrated that $Cl^-$ channels are related to vessel cell proliferation induced by a variety of stimuli. In this study, we investigated a potential role of $Cl^-$ channels in the signaling pathway of LDL effects on hAoSMC proliferation with a focus on the activation of Erk1/2-PI3K/Akt and the subsequent upregulation of Egr-1. $Cl^-$ channel blockers, DIDS, but neither NPPB nor Furosemide, completely abolished the LDL-induced DNA synthesis and cell proliferation. Moreover, DIDS, but not NPPB, significantly decreased LDL-stimulated $Cl^-$ concentration, as judged by flow cytometry analysis using MQAE as a $Cl^-$-detection dye. DIDS pretreatment completely abolished the activation of Erk1/2 and PI3K/Akt in a dose-dependent manner that is the hallmark of LDL activation, as judged by Western blot and proliferation assays. Moreover, pretreatment with DIDS ($Cl^-$ channel blockers) but not LY294002 (PI3K inhibitors) completely abolished the LDL-induced upregulation of Egr-1 to the same extent as PD98059 (MEK inhibitors to inhibit Erk), as judged by Western blot and luciferase reporter assays. This is the first report, to our knowledge, that DIDS-sensitive $Cl^-$-channels play a key role in the LDL-induced cell proliferation of hAoSMCs via the activation of Erk1/2 and PI3K/Akt and the upregulation of Egr-1.

• IMMUNE NETWORK
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• v.7 no.1
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• pp.39-47
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• 2007

Background: Stromal cell-derived factor (SDF)-1 is a potent chemoattractant for activated T cells into the inflamed Rheumatoid arthritis (RA) synovium. To determine the effect of macrophage migration inhibitory factor (MIF) on the production of SDF-1 in the inflamed RA synovium. Methods: The expression of SDF-1 and MIF in RA and Osteoarthritis (OA) synovium was examined by immunohistochemical staining. The SDF-1 was quantified by RT-PCR and ELISA after RA fibroblast like synoviocyte (FLS) were treated with MIF in the presence and absence of inhibitors of intracellular signal molecules. The synovial fluid (SF) and serum levels of MIF and SDF-1 in RA, OA and healthy control were measured by ELISA. Results: Expression of SDF-1 and MIF in synovium was higher in RA patients than in OA patients. The production of SDF-1 was enhanced in RA FLS by MIF stimulation. Such effect of MIF was blocked by the inhibitors of NF-${\kappa}B$. Concentrations of SDF-1 in the serum and SF were higher in RA patients than in OA patients and healthy control. SDF-1 and MIF was overexpressed in RA FLS, and MIF could up-regulate the production of SDF-1 in RA FLS via NF-${\kappa}B$-mediated pathways. Conclusion: These results suggest that an inhibition of interaction between MIF from T cells and SDF-1 of FLS may provide a new therapeutic approach in the treatment of RA.