Targeting PYCR2 inhibits intraperitoneal metastatic tumors of mouse colorectal cancer in a proline-independent approach.

Whether proline deficiency is a metabolic vulnerability in colorectal tumors is unknown. The aim of this study was to investigate the effects of proline metabolism-related genes and exogenous proline on the progression of colorectal cancer (CRC). We aimed to further clarify the role of pyrroline-5-carboxylate reductase (PYCR) 2, a key enzyme of proline synthesis, in the regulation of colorectal intraperitoneal metastatic tumors. This study was carried out based on The Cancer Genome Atlas (TCGA) data, database analysis, single-cell functional analysis, tissue microarray, cell experiments, and animal models. We found that, PYCR2 mRNA and protein levels were upregulated in CRC. The mRNA level of PYCR2 was closely related to the prognosis and tumor metastasis of CRC patients. The upregulated PYCR2 expression was at least partly due to low promoter methylation levels. The nomogram constructed based on PYCR2 expression and clinical characteristics of CRC showed good accuracy in predicting lymph node metastasis. Pycr2 knockdown inhibited epithelial-mesenchymal transition (EMT) of mouse CRC cells. Proline supplementation did not rescue the inhibition of mouse CRC cell proliferation and migration by Pycr2 knockdown. Proline supplementation also did not rescue the suppression of subcutaneous tumors and intraperitoneal metastatic tumors in mice by Pycr2 knockdown. PYCR2 co-expressed genes in TCGA-CRC were enriched in epigenetic modification-related biological processes and molecular functions. Four small molecules with the lowest binding energy to the PYCR2 protein were identified. Collectively, Pycr2 knockdown inhibited mouse CRC progression in a proline-independent approach. PYCR2 may be a promising tumor metastasis predictor and therapeutic target in CRC.

Role of NLR family pyrin domain-containing 3 inflammasome in the activation of pancreatic stellate cells.

NLRP3 inflammasome activation plays an important role in the development of pancreatic fibrosis. However, it is unclear whether the activation of the NLRP3 inflammasome is directly involved in the activation of Pancreatic stellate cells (PSCs). The aim of this study was to investigate the role and mechanism of the NLRP3 inflammasome in the activation of PSCs. In vivo, a rat model of chronic pancreatitis (CP) was induced by intravenous injection of dibutyltin dichloride (DBTC). In vitro, rat primary PSCs were isolated from pancreatic tissues and incubated with the NLRP3 inflammasome activator LPS, the NLRP3 inhibitor MCC950, or NLRP3 siRNA. The results showed that the expression of NLRP3, pro-Caspase-1, Caspase-1 and IL-18 was increased in the rat model of CP and during PSCs activation. LPS increased the protein levels of NLRP3, ASC, Caspase-1, IL-1ß and IL-18 accompanied by the upregulation of α-SMA, Col I and FN expression. Moreover, MCC950 or NLPR3 siRNA decreased the expression of α-SMA, Col I, FN, TGF-ß1 and p-Smad3. Furthermore, MCC950 reversed the LPS-induced upregulation of α-SMA, FN and Col Ⅰ expression in PSCs. This study revealed that the NLRP3 inflammasome is directly involved in the activation of PSCs in vivo and in vitro. Inhibiting NLRP3 suppresses the activation of PSCs through the TGF-ß1/Smad3 pathway.

miR-3065-3p promotes stemness and metastasis by targeting CRLF1 in colorectal cancer.

BACKGROUND: Colorectal cancer is one of the most common malignancy in the world. It has been reported that cancer stem cells (CSCs) serve as the primary drivers of tumorigenesis and tumor progression. There is an urgent need to explore novel molecules that regulate CSCs or their signatures. Increasing evidence has shown that miRNAs are involved in tumorigenesis and progression. Here, we aim to explore the regulatory effect and mechanism of miR-3065-3p on the stemness of colorectal cancer. METHODS: The expression of miR-3065-3p in colorectal cancer and the association of miR-3065-3p expression with prognosis of patients with colorectal cancer were analyzed using TCGA dataset or clinical cases. Gain or loss of function in different models, including colorectal cancer cell lines and orthotopic xenograft or liver metastatic mouse model, were used to investigate the effects of miR-3065-3p on colorectal cancer stemness and metastasis in vitro and in vivo. Cancer stemness was analyzed by detecting the ability of migration and invasion, NANOG, OCT4, and SOX2 expression, ALDH activity and sphere formation. In addition, the interaction of miR-3065-3p and cytokine receptor-like factor 1 (CRLF1) was analyzed theoretically and identified by the luciferase reporter assay. Moreover, the correlation between CRLF1 expression and miR-3065-3p was analyzed in colorectal cancer tissues. Finally, the effect of CRLF1 on the stemness and metastasis of colorectal cancer in vitro and in vivo was assessed. RESULTS: In this report, we found that miR-3065-3p was overexpressed in colorectal cancer and that its high expression was associated with poor prognosis of patients with colorectal cancer. miR-3065-3p promotes the stemness and metastasis of colorectal cancer. Furthermore, CRLF1 was the downstream target of miR-3065-3p and inhibited the stemness of colorectal cancer. In addition, CRLF1 expression was negatively correlated with miR-3065-3p in colorectal cancer tissues. And, CRLF1 mediated the effects of miR-3065-3p on promoting stemness of colorectal cancer cells. CONCLUSION: Our data suggest that miR-3065-3p promoted the stemness and metastasis of colorectal cancer by targeting CRLF1. miR-3065-3p might serve as a promising prognostic marker as well as a therapeutic target for colorectal cancer.

FTY720 induces neutrophil extracellular traps via a NADPH oxidase-independent pathway.

FTY720 is an immunosuppressive agent which has been approved to treat multiple sclerosis (MS). The main object of the present study is to investigate whether FTY720 has the potential to induce the formation of neutrophil extracellular traps (NETs) in vitro. Using Sytox Green assay and fluorescence microscopy, our results showed that FTY720 trigged the NET formation. In contrast to classic NET formation induced by Phorbol 12-myristate 13-acetate (PMA), FTY720-induced NETs were detected earlier and independent of NADPH oxidase (NOX) activity. Pharmacological inhibitor experiments indicated that autophagy was also required for the NET formation induced by FTY720. Moreover, p38 and AKT inhibitor significantly suppressed the NET formation by FTY720, whereas ERK inhibitor had no effect, suggesting that FTY720-induced NETs depended on the activation of p38 and AKT. We further found that citrullination of histone H3 and peptidylarginine deiminase 4 (PAD4) did not mediated FTY720-induced NET formation. Interestingly, necroptosis signaling activation was involved in the vital NET formation by FTY720, however, plasma membrane rupture resulting from necroptosis was not a major component of NET formation described here. Collectively, these findings indicated that FTY720 could be a potential antibacterial drug to protect host against pathogen infection.

C/EBPγ is a critical negative regulator of LPS-/IgG immune complex-induced acute lung injury through the downregulation of C/EBPß-/C/EBPδ-dependent C/EBP transcription activation.

Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome are life-threatening diseases. Despite recent advances in intensive care medicine, the mortality is still as high as 50%, which stems from our insufficient understanding of the underlying mechanisms of the diseases. The roles of C/EBPß and C/EBPδ have been extensively investigated in LPS- and IgG immune complexes-stimulated acute lung injury. However, the effect of C/EBPγ, belonging to the same family as C/EBPß and C/EBPδ, on ALI has not been elucidated. Our previous data have shown that during LPS-/IgG immune complexes-induced ALI, the DNA binding activities of C/EBPγ are obviously reduced. In the present study, we determine whether ALI induced by LPS and IgG immune complexes is affected by C/EBPγ. We find that adenovirus-mediated C/EBPγ expression in the lung tissue alleviates LPS-/IgG immune complexes-stimulated acute pulmonary damage through reducing vascular permeability changes and recruitment of neutrophils into alveolar spaces, which might be linked to a decrease in the production of pro-inflammatory mediators, such as TNF-α and IL-6. Moreover, our data obtained from macrophages in vitro are consistent with the in vivo results. In terms of mechanisms, C/EBPγ might inhibit LPS-/IgG immune complexes-mediated inflammation via alleviating C/EBPß and C/EBPδ transcription activities as reflected by luciferase assays. However, the NF-κB-dependent production of pro-inflammatory mediators is not affected by C/EBPγ. Taken together, C/EBPγ suppresses LPS- and IgG immune complexes-induced pro-inflammatory mediators' production through the downregulation of C/EBP but not NF-κB activation, leading to the subsequent attenuation of ALI. Collectively, our data provide an insight into the critical role of C/EBPγ in acute lung injury.

Overexpression of UBR5 promotes tumor growth in gallbladder cancer via PTEN/PI3K/Akt signal pathway.

As a key regulator of the ubiquitin-proteasome system, ubiquitin protein ligase E3 component N-recognin 5 (UBR5) plays an important role in various cancers. In this study, our results showed for the first time that UBR5 was overexpressed in gallbladder cancer (GBC) tumor tissues. UBR5 overexpression was significantly associated with tumor size, histological and tumor differentiation. UBR5 overexpression was also associated with poor prognosis in patients with GBC. The knockdown of UBR5 remarkably inhibited the cell proliferation and colony formation of GBC-Shandong (SD) cells in vitro and in vivo. UBR5 potentially increases the level of protein kinase B phosphorylation via the degradation of phosphatase and tensin homolog, which contributes to tumor growth in GBC. UBR5 may be an important biomarker for predicting the prognosis of patients with GBC.

Osthole inhibits pancreatic cancer progression by directly exerting negative effects on cancer cells and attenuating tumor-infiltrating M2 macrophages.

Pancreatic cancer has remained a major cause of cancer-related deaths. A hallmark of pancreatic cancer is extensive stromal reactions, resulting in a unique tumor microenvironment, especially the involvement of macrophages. These tumor-educated cells limit the efficacy of chemotherapy. Therefore, it is necessary to identify an effective treatment strategy. In this study, we aimed to explore the anti-tumor and immunomodulatory effects of osthole on pancreatic cancer. We found that osthole suppressed Panc 02 cell migration and proliferation and induced apoptosis as shown in vitro. Osthole also attenuated the development of pancreatic cancer in mice by inhibiting tumor-infiltrating M2 macrophages in our study. Additionally, osthole inhibited the polarization of primary bone marrow cells into M2 macrophages and inhibited the expression of MRC1, CCL22 and TGF-ß in the M2 polarization process in vitro. Detection of the related signaling pathways revealed that osthole exerted immunomodulatory effects on M2 macrophages by down-regulating p-STAT6 and the p-ERK1/2-C/EBP ß axis. These results indicated that osthole has effective anti-tumor and immunomodulatory effects on pancreatic cancer.

Docosahexaenoic acid induces glial cell-line derived neurotrophic factor release in C6 glioma cells: Implications of antidepressant effects for docosahexaenoic acid.

Dietary deficiency of n-3 polyunsaturated fatty acids (PUFAs) is involved in the pathophysiology and etiology of major depressive disorder. Supplementation with docosahexaenoic acid (DHA) exerts antidepressant-like effect; however, the molecular mechanism of DHA action remains unclear. Here we examined the effects of DHA on the modulation of glial cell line-derived neurotrophic factor (GDNF), which is essential for neural development, plasticity, neurogenesis, and survival. We demonstrated that DHA treatment significantly increased GDNF release in a concentration dependent manner in rat C6 glioma cells (C6 cells) and primary cultured rat astrocytes, which is also associated with increased expression of GDNF mRNA. Furthermore, the DHA-induced GDNF production was inhibited by mitogen activated protein kinase (MEK) inhibitor and protein kinase C (PKC) inhibitor, but not protein kinase A (PKA) inhibitor and p38 mitogen-activated protein kinase (MAPK) inhibitor. DHA-induced extracellular signal-regulated kinase (ERK) activation is dependent on the PKC, as demonstrated by its reversibility after pretreatment with PKC inhibitor. Moreover, fibroblast growth factor receptor (FGFR inhibitor) but not epidermal growth factor receptor (EGFR) inhibitor blocked the activation of ERK induced by DHA treatment. DHA-induced GDNF production was also blocked by FGFR inhibitor, suggesting that FGFR is also involved in ERK activation-mediated GDNF production induced by DHA. Our study demonstrates that DHA-induced release of GDNF, mediated by PKC and FGFR-dependent on ERK activation, may contribute to the antidepressant-like effect of DHA.

Saikosaponin a promotes neutrophil extracellular trap formation and bactericidal activity.

This study aimed to investigate the effects of SSa, one of the major triterpenoid saponins extracted from Radix bupleuri, on neutrophil extracellular trap (NET) formation and the mechanism associated with this process. Using Sytox green and immunofluorescence assays, we found SSa rapidly induced NET formation, which depended on NADPH oxidase (NOX)-independent ROS production and autophagy. Pharmacologic inhibitor studies indicated that ERK and PI3K/AKT signalling were also required for SSa-induced NET formation, whereas protein arginine deiminase 4 (PAD4) was not required. Furthermore, we found that SSa promoted neutrophil bactericidal activity mainly through NET formation. Based on flow cytometry and the Cell Counting Kit-8 (CCK-8) assays, the results demonstrated that SSa-induced NET formation occurred without neutrophil death. Taken together, these findings indicated that SSa could be a potential natural product to boost innate immune defense against pathogen attack via NET formation.

Saikosaponin d modulates the polarization of tumor-associated macrophages by deactivating the PI3K/AKT/mTOR pathway in murine models of pancreatic cancer.

The tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) poses a major obstacle to traditional and immunomodulatory cancer therapies and is closely associated with macrophage polarization. Saikosaponin d (SSd), a major active component of triterpene saponins derived from Bupleurum falcatum, has anti-inflammatory and antitumor activities. However, whether SSd can regulate immune cells during the development of the TME in PDAC remains unknown. In the present study, we aimed to analyze the role of SSd in regulating immune cells in the PDAC TME, especially the polarization of macrophages, and examine the related mechanisms. An orthotopic PDAC cancer model was used to investigate the antitumor activities and the regulation of immune cells in vivo. In vitro, bone marrow mononuclear (BM-MNC) cells and RAW 264.7 cells were used to induce the M2 macrophage phenotype and examine the effects and molecular mechanism of SSd on M2 macrophage polarization. The results revealed that SSd could directly inhibit the apoptosis and invasion of pancreatic cancer cells, modulate the immunosuppressive microenvironment and reactivate the local immune response, especially by decreasing the shift toward M2 macrophage polarization by downregulating phosphorylated STAT6 levels and the PI3K/AKT/mTOR signaling pathway. Furthermore, 740-Y-P (PI3K activator) was used to verify that SSd inhibited M2 polarization in RAW264.7 cells via the PI3K/AKT/mTOR signaling pathway. In conclusion, this study provided experimental evidence of the antitumor effect of SSd, especially in the regulation of M2 macrophage polarization, and demonstrated that SSd may be a promising therapeutic agent in PDAC.

Protective effect of liriodendrin on IgG immune complex-induced acute lung injury via inhibiting SRC/STAT3/MAPK signaling pathway: a network pharmacology research.

The primary objectives of this research were to investigate the protective effects of liriodendrin against IgG immune complex (IgG-IC)-induced acute lung injury (ALI) and to elucidate the underlying mechanisms. This study employed a mouse and cell model of IgG-IC-induced acute lung injury. Lung tissue was stained with hematoxylin-eosin to observe pathological alterations and arterial blood gas analysis was tested. Inflammatory cytokines, including interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-alpha (TNF-α), were measured using ELISA. The mRNA expression of inflammatory cytokines was assessed via RT-qPCR. Molecular docking and enrichment analysis were combined to identify the most potential signaling pathways modulated by liriodendrin, which were then verified using western blot analysis in IgG-IC-induced ALI models. We identified 253 shared targets between liriodendrin and IgG-IC-induced acute lung injury from the database. Through network pharmacology, enrichment analysis, and molecular docking, SRC was determined to be the most closely associated target of liriodendrin in IgG-IC-induced ALI. Pretreatment with liriodendrin notably reduced the increased cytokine secretion of IL-1ß, IL-6, and TNF-α. Histopathological analysis of lung tissue demonstrated a protective effect of liriodendrin on IgG-IC-induced acute lung injury in mice. Arterial blood gas analysis showed liriodendrin ameliorated acidosis and hypoxemia efficiently. Further studies revealed that liriodendrin pretreatment substantially attenuated the elevated phosphorylation levels of SRC's downstream components (JNK, P38, and STAT3), suggesting that liriodendrin may protect against IgG-IC-induced ALI via the SRC/STAT3/MAPK pathway. Our findings indicate that liriodendrin protects against IgG-IC-induced acute lung injury by inhibiting the SRC/STAT3/MAPK signaling pathway, suggesting that liriodendrin may serve as a potential treatment for acute lung injury caused by IgG-IC.

S1P/S1PR2 promote pancreatic stellate cell activation and pancreatic fibrosis in chronic pancreatitis by regulating autophagy and the NLRP3 inflammasome.

Sphingosine-1-phosphate (S1P) is a bioactive lipid molecule that governs various functions by embedding its receptor, S1PR, in different cells. Chronic pancreatitis (CP) is characterized by pancreatic fibrosis via activation of pancreatic stellate cells (PSCs). However, the effect of S1P on CP and PSC activation is still unknown. Here, we conducted a series of experiments to explore the effect of S1P on a CP rat model and primary cultured PSCs. In vivo, CP was induced by intravenous injection of dibutyltin dichloride. S1P was administered at a dosage of 200 µg/kg body weight per day by intraperitoneal injection. After 4 weeks, serum, plasma and pancreas samples were collected for molecular analysis and histological detection. In vitro, PSCs were isolated and cultured for treatment with different doses of S1P. 3MA and MCC950 were used to determine the effect of S1P on PSC activation by regulating autophagy and the NLRP3 inflammasome. JTE013 and Si-S1PR2 were applied to verify that the functions of S1P were realized by combining with S1PR2. Cells were collected for RT‒PCR, western blotting and immunofluorescence. The results showed that S1P was increased in the plasma and pancreatic tissue of CP rats. When S1P was administered to CP rats, the function and histomorphology of the pancreas were severely impaired. In addition, S1P promoted PSC activation, heightened autophagy and enhanced the NLRP3 inflammasome in vivo and in vitro. Moreover, S1PR2 mediated the effect of S1P on PSC activation by regulating autophagy and the NLRP3 inflammasome sequentially. In conclusion, S1P binding to S1PR2 promoted PSC activation and pancreatic fibrosis in CP by regulating autophagy and the NLRP3 inflammasome. These findings provide a theoretical basis for targeting S1P/S1PR2 to treat pancreatic fibrosis and further suggest that considering the role of autophagy and the NLRP3 inflammasome may help with the treatment pancreatic fibrosis.

[Effect of Liangxue Huoxue decoction on intestinal flora and NLRP3/caspase-1/GSDMD signaling pathway in mice model of sepsis-induced acute kidney injury].

OBJECTIVE: To investigate the effect of Liangxue Huoxue decoction on intestinal flora, intestinal barrier and NOD-like receptor protein 3 (NLRP3)/caspase-1/gasdermin D (GSDMD) pyroptosis signaling pathway in mice model of sepsis-induced acute kidney injury (AKI). METHODS: The model of AKI was established by cecal ligation and perforation (CLP). Thirty male C57BL/6 mice were randomly divided into sham operation group (Sham group), sepsis group (CLP group) and sepsis+Liangxue Huoxue decoction (CLP+LXHX group), with 10 mice in each group. Mice in Sham group only underwent laparotomy. Two hours before model establishment, mice in CLP+LXHX group were treated with Liangxue Huoxue decoction (6 g/kg) by gavage; mice in Sham group and CLP group were given equal volume of normal saline by gavages. After 24 hours of modeling, all mice were sacrificed under anesthesia, and the colon and kidney tissues and fresh feces in the colon were taken. The pathological changes of kidney and colon were observed by hematoxylin-eosin (HE) staining under light microscope. Real-time polymerase chain reaction (RT-PCR) was used to detect inflammatory factors (interleukins, IL-1ß and IL-18) in renal tissue. The expressions of NLRP3, caspase-1 and GSDMD were detected by Western blotting. The changes of intestinal flora in mice were detected by 16S rDNA high-throughput sequencing. RESULTS: Compared with the Sham group, the inflammatory cell infiltration of the kidney tissue was increased and the kidney became vacuolated in CLP group, the mRNA expressions of IL-1ß, IL-18, and the protein expressions of NLRP3, caspase-1 and GSDMD were significantly increased in CLP group, the species richness of intestinal microflora decreased significantly, the relative abundance of Enterococcus and Escherichia-Shigella increased significantly, and the relative abundance of Ileibacterium, Alloprevotella, Lachnospiraceae, Klebsiella and Parasutterella increased significantly in CLP group. Compared with CLP group, Liangxue Huoxue decoction can significantly reduce the pathological changes of kidney and colon tissue, reduce the pathological score (1.75±0.43 vs. 3.50±0.50 for kidney tissue, 1.25±0.43 vs. 4.50±0.50 for colon tissue, both P < 0.05), improve the composition of intestinal flora, reduce the relative abundance of Enterococcus and Escherichia-Shigella, and significantly increase the relative abundance of Lactobacillus and Akkermansia. In addition, Liangxue Huoxue decoction can significantly reduce mRNA expressions of IL-1ß and IL-18 in kidney tissue [IL-1ß mRNA (2-ΔΔCt): 1.59±0.05 vs. 4.61±0.88, IL-18 mRNA (2-ΔΔCt): 1.69±0.17 vs. 2.86±0.63, both P < 0.05] and the protein expressions of NLRP3, caspase-1 and GSDMD (NLRP3/GAPDH: 0.71±0.04 vs. 0.89±0.01, caspase-1/GAPDH: 1.04±0.04 vs. 1.48±0.04, GSDMD/GAPDH: 0.90±0.01 vs. 1.41±0.02, all P < 0.05). CONCLUSIONS: Liangxue Huoxue decoction has obvious protective effect on AKI induced by sepsis. It can improve intestinal barrier by regulating intestinal flora, thereby inhibiting the activation of NLRP3/caspase-1/GSDMD signaling pathway in kidney tissue and reducing the expression of proptosis-related inflammatory factors.

Verbenalin alleviates acute lung injury induced by sepsis and IgG immune complex through GPR18 receptor.

Acute lung injury is significantly associated with the aberrant activation and pyroptosis of alveolar macrophages. Targeting the GPR18 receptor presents a potential therapeutic approach to mitigate inflammation. Verbenalin, a prominent component of Verbena in Xuanfeibaidu (XFBD) granules, is recommended for treating COVID-19. In this study, we demonstrate the therapeutic effect of verbenalin on lung injury through direct binding to the GPR18 receptor. Verbenalin inhibits the activation of inflammatory signaling pathways induced by lipopolysaccharide (LPS) and IgG immune complex (IgG IC) via GPR18 receptor activation. The structural basis for verbenalin's effect on GPR18 activation is elucidated through molecular docking and molecular dynamics simulations. Furthermore, we establish that IgG IC induces macrophage pyroptosis by upregulating the expression of GSDME and GSDMD through CEBP-δ activation, while verbenalin inhibits this process. Additionally, we provide the first evidence that IgG IC promotes the formation of neutrophil extracellular traps (NETs), and verbenalin suppresses NETs formation. Collectively, our findings indicate that verbenalin functions as a "phytoresolvin" to promote inflammation regression and suggests that targeting the C/EBP-δ/GSDMD/GSDME axis to inhibit macrophage pyroptosis may represent a novel strategy for treating acute lung injury and sepsis.

Antitumor effect of tubeimoside-I on murine colorectal cancers through PKM2-dependent pyroptosis and immunomodulation.

Induction of cancer cell death is an established treatment strategy, but chemotherapy drug-mediated apoptosis can be evaded by many tumors. Pyroptosis is a type of inflammatory programmed cell death (PCD) that is important for organism immunity. Tubeimoside-I (TBMS1) is a plant-derived component that exhibits antitumor activity. However, it is unclear how TBMS1 induces pyroptosis to inhibit colorectal cancer (CRC). In this study, we demonstrated that TBMS1 is able to induce pyroptosis in murine CRC cells and releases pro-inflammatory cytokines. Mechanistically, we found that TBMS1 inhibits CRC cell proliferation and migration and induces pyroptosis by activating caspase-3 and cleaving gasdermin E (GSDME) through the inhibition of PKM2. In the animal experiments, TBMS1 attenuated the weight of solid tumors, increased the proportion of CD8+ cytotoxic T cells, and reduced the content of M2-type macrophages in the spleen of tumor-bearing mice. Furthermore, TBMS1 inhibited M2-type polarization by blocking STAT6 pathway activation in RAW 264.7 cells. To sum up, our findings suggest that TBMS1 triggers pyroptosis in CRC by acting on the PKM2/caspase-3/GSDME signaling pathway. Additionally, it modulates the antitumor immune response in CRC murine models. This study provides a promising basis for the potential use of TBMS1 in treating CRC.

Syringaresinol alleviates IgG immune complex induced acute lung injury via activating PPARγ and suppressing pyroptosis.

Acute lung injury (ALI) is a life-threatening condition characterized by severe lung inflammation and tissue damage. In this study, we investigate the potential therapeutic efficacy of (+)-Syringaresinol (SYG), a natural compound known for its antioxidant and anti-inflammatory properties, in alleviating ALI induced by IgG immune complexes (IgG-IC). Using MH-S cells as a model, we explore SYG's ability to target peroxisome proliferator-activated receptor gamma (PPARγ) and its anti-inflammatory properties. Our comprehensive investigation aims to elucidate the specific molecular mechanisms underlying SYG's effects against pyroptosis, as revealed through transcriptomic analysis. Validation in C57BL/6 mice provides in vivo support. Our findings indicate that SYG effectively mitigates IgG-IC-induced lung damage, as evidenced by a significant reduction in lung inflammation and tissue injury. SYG treatment notably decreases pro-inflammatory cytokine levels (TNF-α, IL-6, IL-1ß) in both lung tissue and cells. Molecular docking analysis reveals SYG's robust binding to PPARγ, leading to the inhibition of IgG-IC-induced inflammatory signaling pathways. Additionally, transcriptomic analysis unveils SYG's potential in suppressing macrophage pyroptosis, potentially through the downregulation of key inflammatory mediators (NLRP3, GSDMD, Caspase-1). In summary, our study presents compelling evidence supporting SYG as an effective therapeutic agent for ALI. SYG's activation of PPARγ contributes to the suppression of NF-κB and C/EBPs expression, thereby mitigating inflammation. Moreover, SYG demonstrates the ability to inhibit macrophage pyroptosis by targeting the NLRP3/GSDMD/caspase-1 axis.

Dioscin modulates macrophages polarization and MDSCs differentiation to inhibit tumorigenesis of colitis-associated colorectal cancer.

It has been reported that colitis is one of risk factors in colorectal cancer (CRC). Intervention of intestinal inflammation and in the early stage of tumorigenesis is of great significance to control the incidence and mortality of CRC. In recent years, natural active products of traditional Chinese medicine have been confirmed that they had made great progress in disease prevention. Here, we showed that Dioscin, a natural active product of Dioscorea nipponica Makino, inhibited initiation and tumorigenesis of AOM/DSS-induced colitis-associated colon cancer (CAC), including alleviating colonic inflammation, improving intestinal barrier function and decreasing tumor burden. In addition, we also explored the immunoregulatory effect of Dioscin on mice. The results showed that Dioscin modulated M1/M2 macrophages phenotype in spleen and decreased monocytic myeloid-derived suppressor cells (M-MDSCs) population in blood and spleen of mice. The in vitro assay demonstrated that Dioscin promoted M1 as well as inhibited M2 macrophages phenotype in LPS- or IL-4-induced bone marrow-derived macrophages (BMDMs) model. Based on the plasticity of MDSCs and its ability to differentiate into M1/M2 macrophages, we here found that Dioscin increased M1- and decreased M2-like phenotype during the process of MDSCs differentiation in vitro, suggesting Dioscin promoted MDSCs differentiate into M1 as well as inhibited its differentiation into M2 macrophages. Taken together, our study indicated that Dioscin had the inhibitory effect on the initial of tumorigenesis at early stage of CAC via the ant-inflammatory effect, which provided a natural active candidate for effective prevention of CAC.

Xuanfei Baidu Decoction suppresses complement overactivation and ameliorates IgG immune complex-induced acute lung injury by inhibiting JAK2/STAT3/SOCS3 and NF-κB signaling pathway.

BACKGROUND: The significant clinical efficacy of Xuanfei Baidu Decoction (XFBD) is proven in the treatment of patients with coronavirus disease 2019 (COVID-19) in China. However, the mechanisms of XFBD against acute lung injury (ALI) are still poorly understood. METHODS: In vivo, the mouse model of ALI was induced by IgG immune complexes (IgG-IC), and then XFBD (4g/kg, 8g/kg) were administered by gavage respectively. 24 h after inducing ALI, the lungs were collected for histological and molecular analysis. In vitro, alveolar macrophages inflammation models induced by IgG-IC were performed and treated with different dosage of XFBD-containing serum to investigate the protective role and molecular mechanisms of XFBD. RESULTS: The results revealed that XFBD mitigated lung injury and significantly downregulated the production of pro-inflammatory mediators in lung tissues and macrophages upon IgG-IC stimulation. Notably, XFBD attenuated C3a and C5a generation, inhibited the expression of C3aR and C5aR and suppressed the activation of JAK2/STAT3/SOCS3 and NF-κB signaling pathway in lung tissues and macrophages induced by IgG-IC. Moreover, in vitro experiments, we verified that Colivelin TFA (CAF, STAT3 activator) and C5a treatment markedly elevated the IgG-IC-triggered inflammatory responses in macrophages and XFBD weakened the effects of CAF or C5a. CONCLUSION: XFBD suppressed complement overactivation and ameliorated IgG immune complex-induced acute lung injury by inhibiting JAK2/STAT3/SOCS3 and NF-κB signaling pathway. These data contribute to understanding the mechanisms of XFBD in COVID-19 treatment.

Dihydroartemisinin inhibits the growth of pancreatic cells by inducing ferroptosis and activating antitumor immunity.

Dihydroartemisinin (DHA) exhibits a direct antitumor effect in various tumor models. However, the mechanism of DHA inducing ferroptosis and activating antitumor immunity remains obscure. Therefore, our study was dedicated to investigate the effect of DHA on ferroptosis and tumor microenvironment and elucidate the underlying molecular mechanism. PDAC orthotopic tumor model was used to investigate tumor proliferation and the population of immune cell in vivo, including M2-type macrophages (M2), myeloid-derived suppressor cells (MDSCs), CD4+T cells, CD8+T cells, NK cells and NKT cells. Levels of GPX4, SLC7A11, P53 and ALOX12 were determined by Real-time PCR and Western blot. CCK8 assay was performed to detect cell viability, and the ferroptosis was distinguished by flow cytometry. Our results showed that DHA inhibited pancreatic cancer cell proliferation. In addition, DHA induced cell ferroptosis by up-regulating the expression of P53 and ALOX12, which was blocked by baicalein (a selective ALOX12 inhibitor). However, DHA also up-regulated the expression of GPX4 and SLC7A11. On the other hand, DHA significantly decreased the suppressive expansion of M2 and MDSCs. Moreover, DHA increased the immune cell population of CD8+T cells, NK cells and NKT cells in the tumor tissues of the tumor-bearing mice. Whereas, the DHA treatment did not affect the frequencies of M2, MDSCs, CD4+T, CD8+T, NK and NKT cells in the spleen. Our research provided experimental evidences on the activity and mechanism of ferroptosis induced by DHA and revealed that DHA regulated tumor local immunosuppressive microenvironment.

Imaging mass cytometry: High-dimensional and single-cell perspectives on the microenvironment of solid tumours.

Imaging mass cytometry (IMC) is a new technology integrating mass spectrometry, high-resolution laser ablation and immunohistochemistry/cytochemistry. A unique high-dimensional perspective comprehensively and accurately depicts the complex interaction of phenotype, signalling pathway and tumour microenvironment and is widely used in solid tumours. However, the application scenarios of IMC in basic medicine and clinical research in solid tumours lack systematic introduction and classification. This paper reviews the application of IMC in depicting the panorama of the tumour microenvironment, revealing tumour spatial heterogeneity, clarifying tumour pharmacological mechanisms, assisting in new drug development, and dynamically evaluating the efficacy of immunotherapy in solid tumours.