Antirheumatic drug leflunomide attenuates atherosclerosis by regulating lipid metabolism and endothelial dysfunction via DHODH/AMPK signaling pathway.

The probability of cardiovascular events has been reported lower in rheumatoid arthritis (RA) patients treated with leflunomide. However, the anti-atherosclerotic and cardiovascular protective effects and metabolism of leflunomide are not explored. In this study, we assessed the potential benefits of leflunomide on atherosclerosis and revealed the underlying mechanism. ApoE-/- mice were fed a western diet (WD) alone or supplemented with leflunomide (20 mg/kg, oral gavage, once per day) for 12 weeks. Samples of the aorta, heart, liver, serum, and macrophages were collected. We found that leflunomide significantly reduced lesion size in both en-face aortas and aortic root in WD-fed ApoE-/- mice. Leflunomide also obviously improved dyslipidemia, reduced hepatic lipid content, and improved disorders of glucose and lipid metabolism in vivo. RNA-Seq results showed that leflunomide effectively regulated the genes' expression involved in the lipid metabolism pathway. Importantly, leflunomide significantly increased the phosphorylation levels of AMPKα and acetyl-CoA carboxylase (ACC) in vivo. Furthermore, leflunomide and its active metabolite teriflunomide suppressed lipid accumulation in free fatty acid (FFA)-induced AML12 cells and improved endothelial dysfunction in palmitic acid (PA)-induced HUVECs through activating AMPK signaling and inhibiting dihydroorotate dehydrogenase (DHODH) signaling pathway. We present evidence that leflunomide and teriflunomide ameliorate atherosclerosis by regulating lipid metabolism and endothelial dysfunction. Our findings suggest a promising use of antirheumatic small-molecule drugs leflunomide and teriflunomide for the treatment of atherosclerosis and related cardiovascular diseases (CVDs).

A novel small-molecule PCSK9 inhibitor E28362 ameliorates hyperlipidemia and atherosclerosis.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 µM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fraction in both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 µM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.

The Natural Product Secoemestrin C Inhibits Colorectal Cancer Stem Cells via p38-S100A8 Feed-Forward Regulatory Loop.

Cancer stem cells (CSCs) are closely associated with tumor initiation, metastasis, chemoresistance, and recurrence, which represent some of the primary obstacles to cancer treatment. Targeting CSCs has become an important therapeutic approach to cancer care. Secoemestrin C (Sec C) is a natural compound with strong anti-tumor activity and low toxicity. Here, we report that Sec C effectively inhibited colorectal CSCs and non-CSCs concurrently, mainly by inhibiting proliferation, self-renewal, metastasis, and drug resistance. Mechanistically, RNA-seq analysis showed that the pro-inflammation pathway of the IL17 axis was enriched, and its effector S100A8 was dramatically decreased in Sec C-treated cells, whose roles in the stemness of CSCs have not been fully clarified. We found that the overexpression of S100A8 hindered the anti-CSCs effect of Sec C, and S100A8 deficiency attenuated the stemness traits of CSCs to enhance the Sec C killing activity on them. Meanwhile, the p38 signal pathway, belonging to the IL17 downstream axis, can also mediate CSCs and counter with Sec C. Notably, we found that S100A8 upregulation increased the p38 protein level, and p38, in turn, promoted S100A8 expression. This indicated that p38 may have a mutual feedback loop with S100A8. Our study discovered that Sec C was a powerful anti-colorectal CSC agent, and that the positive feedback loop of p38-S100A8 mediated Sec C activity. This showed that Sec C could act as a promising clinical candidate in colorectal cancer treatment, and S100A8 could be a prospective drug target.

Trichostatin C Synergistically Interacts with DNMT Inhibitor to Induce Antineoplastic Effect via Inhibition of Axl in Bladder and Lung Cancer Cells.

Aberrant epigenetic modifications are fundamental contributors to the pathogenesis of various cancers. Consequently, targeting these aberrations with small molecules, such as histone deacetylase (HDAC) inhibitors and DNA methyltransferase (DNMT) inhibitors, presents a viable strategy for cancer therapy. The objective of this study is to assess the anti-cancer efficacy of trichostatin C (TSC), an analogue of trichostatin A sourced from the fermentation of Streptomyces sp. CPCC 203909. Our investigations reveal that TSC demonstrates potent activity against both human lung cancer and urothelial bladder cancer cell lines, with IC50 values in the low micromolar range. Moreover, TSC induces apoptosis mediated by caspase 3/7 and arrests the cell cycle at the G2/M phase. When combined with the DNMT inhibitor decitabine, TSC exhibits a synergistic anti-cancer effect. Additionally, protein analysis elucidates a significant reduction in the expression of the tyrosine kinase receptor Axl. Notably, elevated concentrations of TSC correlate with the up-regulation of the transcription factor forkhead box class O1 (FoxO1) and increased levels of the proapoptotic proteins Bim and p21. In conclusion, our findings suggest TSC as a promising anti-cancer agent with HDAC inhibitory activity. Furthermore, our results highlight the potential utility of TSC in combination with DNMT inhibitors for cancer treatment.

Toxicity Study on Crude Alkaloid Extracts of Houttuyniae herba Based on Zebrafish and Mice.

Houttuyniae herba has a long history of medicinal and edible homology in China. It has the functions of clearing heat and detoxifying, reducing swelling and purulent discharge, diuresis, and relieving gonorrhea. It is mainly distributed in the central, southeastern, and southwestern provinces of China. Houttuyniae herba has been designated by the National Ministry of Health of China as a dual-use plant for both food and medicine. Comprising volatile oils, flavonoids, and alkaloids as its primary constituents, Houttuyniae herba harbors aristolactams, a prominent subclass of alkaloids. Notably, the structural affinity of aristolactams to aristolochic acids is discernible, the latter known for its explicit toxicological effects. Additionally, the safety study on Houttuyniae herba mainly focused on the ethanol, methanol, or aqueous extract. In this study, both zebrafish and mice were used to evaluate the acute toxicity of the total alkaloids extracts from Houttuyniae herba (HHTAE). The zebrafish experiment showed that a high concentration (0.1 mg/mL) of HHTAE had a lethal effect on zebrafish embryos. Furthermore, the mice experiment results showed that, even at a higher dose of 2000 mg/kg, HHTAE was not toxic. In conclusion, HHTAE was of low safety risk.

Rho GTPase-activating protein 1 promotes hepatocellular carcinoma progression via modulation by CircPIP5K1A/MiR-101-3p.

AIM: There has been an increased focus on regulating cell function with Rho family GTPases, including proliferation, migration/invasion, polarity, and adhesion. Due to the challenges involved in targeting Rho family GTPases directly, it may be more effective to target their regulators, such as Rho GTPase-activating protein 1 (ARHGAP1). This present research was performed to define the clinical significance of ARHGAP1 expression, as well as its regulatory mechanisms in hepatocellular carcinoma. METHODS: ARHGAP1 and miR-101-3p expression of liver cancer patients, and their relevance with clinicopathological characteristics and prognosis were analyzed by the Cancer Genome Atlas sequencing data, and verified using samples of hepatocellular carcinoma patients. The interactions between miR-101-3p and ARHGAP1 or circPIP5K1A were validated by bioinformatic analyses, as well as confirmed by quantitative reverse transcription polymerase chain reaction, western blotting, and dual-luciferase reporter analysis. Plate clonality assays, cell adhesion and migration experiments, and proliferation experiments were used for assessing the participation of the circPIP5K1A/miR-101-3p/ARHGAP1 pathway in cell proliferation and motility. RESULTS: Elevated ARHGAP1 and reduced miR-101-3p expression are related to poorer survival. MiR-101-3p targets ARHGAP1 to suppress hepatocellular carcinoma cell colony formation and invasion, whereas miR-101-3p inhibitor reverses liver cancer proliferation and metastasis suppression caused by ARHGAP1 knockdown. In addition, circPIP5K1A, which is mainly distributed in the cytosol, showed carcinogenic effects by sponging miR-101-3p, thus regulating ARHGAP1 expression. CONCLUSIONS: ARHGAP1 serves as an oncogenic gene in liver cancer, and the expression thereof is regulated by circPIP5K1A through sponging miR-101-3p.

Visualization of the Ferroptosis in Atherosclerotic Plaques with Nanoprobe Engineered by Macrophage Cell Membranes.

Atherosclerosis (AS) is the root cause of cardiovascular diseases. Ferroptosis is characterized by highly iron-dependent lipid peroxidation and has been reported to play an important role in the pathogenesis of AS. Visualization of the ferroptosis process in atherosclerotic plaques is of great importance for diagnosing and treating AS. In this work, the rationally designed fluorescent probe FAS1 exhibited excellent advantages including large Stokes shift, sensitivity to environmental viscosity, good photostability, and improved water solubility. It also could co-locate with commercial lipid droplets (LDs) probes (BODIPY 493/503) well in RAW264.7 cells treated by the ferroptosis inducer. After self-assembly into nanoparticles and then encapsulation with macrophage membranes, the engineered FAS1@MM NPs could successfully target the atherosclerotic plaques in Western diet-induced apolipoprotein E knockout (ApoE-/-) mice and reveal the association of ferroptosis with AS through fluorescence imaging in vivo. This study may provide additional insights into the roles of ferroptosis in the diagnosis and treatment of AS.

Nanoparticles (NPs)-mediated Siglec15 silencing and macrophage repolarization for enhanced cancer immunotherapy.

T cell infiltration and proliferation in tumor tissues are the main factors that significantly affect the therapeutic outcomes of cancer immunotherapy. Emerging evidence has shown that interferon-gamma (IFNγ) could enhance CXCL9 secretion from macrophages to recruit T cells, but Siglec15 expressed on TAMs can attenuate T cell proliferation. Therefore, targeted regulation of macrophage function could be a promising strategy to enhance cancer immunotherapy via concurrently promoting the infiltration and proliferation of T cells in tumor tissues. We herein developed reduction-responsive nanoparticles (NPs) made with poly (disulfide amide) (PDSA) and lipid-poly (ethylene glycol) (lipid-PEG) for systemic delivery of Siglec15 siRNA (siSiglec15) and IFNγ for enhanced cancer immunotherapy. After intravenous administration, these cargo-loaded could highly accumulate in the tumor tissues and be efficiently internalized by tumor-associated macrophages (TAMs). With the highly concentrated glutathione (GSH) in the cytoplasm to destroy the nanostructure, the loaded IFNγ and siSiglec15 could be rapidly released, which could respectively repolarize macrophage phenotype to enhance CXCL9 secretion for T cell infiltration and silence Siglec15 expression to promote T cell proliferation, leading to significant inhibition of hepatocellular carcinoma (HCC) growth when combining with the immune checkpoint inhibitor. The strategy developed herein could be used as an effective tool to enhance cancer immunotherapy.

Foxp3-mediated blockage of ryanodine receptor 2 underlies contact-based suppression by regulatory T cells.

The suppression mechanism of Tregs remains an intensely investigated topic. As our focus has shifted toward a model centered on indirect inhibition of DCs, a universally applicable effector mechanism controlled by the transcription factor forkhead box P3 (Foxp3) expression has not been found. Here, we report that Foxp3 blocked the transcription of ER Ca2+-release channel ryanodine receptor 2 (RyR2). Reduced RyR2 shut down basal Ca2+ oscillation in Tregs, which reduced m-calpain activities that are needed for T cells to disengage from DCs, suggesting a persistent blockage of DC antigen presentation. RyR2 deficiency rendered the CD4+ T cell pool immune suppressive and caused it to behave in the same manner as Foxp3+ Tregs in viral infection, asthma, hypersensitivity, colitis, and tumor development. In the absence of Foxp3, Ryr2-deficient CD4+ T cells rescued the systemic autoimmunity associated with scurfy mice. Therefore, Foxp3-mediated Ca2+ signaling inhibition may be a central effector mechanism of Treg immune suppression.

The functions and regulatory pathways of S100A8/A9 and its receptors in cancers.

Inflammation primarily influences the initiation, progression, and deterioration of many human diseases, and immune cells are the principal forces that modulate the balance of inflammation by generating cytokines and chemokines to maintain physiological homeostasis or accelerate disease development. S100A8/A9, a heterodimer protein mainly generated by neutrophils, triggers many signal transduction pathways to mediate microtubule constitution and pathogen defense, as well as intricate procedures of cancer growth, metastasis, drug resistance, and prognosis. Its paired receptors, such as receptor for advanced glycation ends (RAGEs) and toll-like receptor 4 (TLR4), also have roles and effects within tumor cells, mainly involved with mitogen-activated protein kinases (MAPKs), NF-κB, phosphoinositide 3-kinase (PI3K)/Akt, mammalian target of rapamycin (mTOR) and protein kinase C (PKC) activation. In the clinical setting, S100A8/A9 and its receptors can be used complementarily as efficient biomarkers for cancer diagnosis and treatment. This review comprehensively summarizes the biological functions of S100A8/A9 and its various receptors in tumor cells, in order to provide new insights and strategies targeting S100A8/A9 to promote novel diagnostic and therapeutic methods in cancers.

HMGB1 released from dead tumor cells after insufficient radiofrequency ablation promotes progression of HCC residual tumor via ERK1/2 pathway.

BACKGROUND: Radiofrequency ablation (RFA) is a first-line treatment for early-stage hepatocellular carcinoma (HCC). However, the recurrence after RFA remains an urgent challenge. Current studies have shown that residual tumor after RFA is an important cause of recurrence. OBJECTIVE: We hypothesized that the products of dead tumor cells after RFA have direct effects on the development of residual tumors. Further, we investigated the underlying mechanisms. METHODS: The proliferation and invasion ability of HepG2 and Huh7 cells were assessed using CCK-8, colony formation, EdU, transwell invasion and migration assay. Immunofluorescence and western blotting were used to show HMGB1 released from dead tumor cells. The levels of MMP2, MMP9, CyclinE1 and pERK1/2 were determined using western blotting. Finally, in vivo validation was performed in BALB/c nude mice xenograft tumor models. RESULTS: The products of dead tumor cells after thermal treatment can promote the proliferation and invasion of residual HCC cells. Dead tumor cells could release high-mobility group box 1 (HMGB1) after thermal treatment. Similar to the products of dead tumor cells, the recombinant protein of HMGB1 can promote the proliferation and invasion of residual HCC cells. Moreover, HMGB1 could bind to receptor of advanced glycation end-products. Then, it activated the ERK1/2 pathway and significantly upregulated the expressions of MMP2, MMP9, and CyclinE1. CONCLUSION: Our study reveals that HMGB1 released by dead tumor cells after thermal treatment can promote the proliferation and invasion of residual HCC cells. Hence, the HMGB1/RAGE/ERK1/2 pathway is a potential target for improving the prognosis of HCC after radiofrequency ablation.

Trichostatin D as a Novel KLF2 Activator Attenuates TNFα-Induced Endothelial Inflammation.

Krüppel-like factor 2 (KLF2) is an atherosclerotic protective transcription factor that maintains endothelial cell homeostasis through its anti-inflammatory, anti-oxidant, and antithrombotic properties. The aim of this study was to discover KLF2 activators from microbial secondary metabolites and explore their potential molecular mechanisms. By using a high-throughput screening model based on a KLF2 promoter luciferase reporter assay, column chromatography, electrospray ionization mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) spectra, trichostatin D (TSD) was isolated from the rice fermentation of Streptomyces sp. CPCC203909 and identified as a novel KLF2 activator. Real-time-quantitative polymerase chain reaction (RT-qPCR) results showed that TSD upregulated the mRNA level of KLF2 in endothelial cells. Functional assays showed that TSD attenuated monocyte adhesion to endothelial cells, decreased vascular cell adhesion protein 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1) expression, and exhibited an anti-inflammatory effect in tumor necrosis factor alpha (TNFα)-induced endothelial cells. We further demonstrated through siRNA and western blot assays that the effects of TSD on monocyte adhesion and inflammation in endothelial cells were partly dependent on upregulating KLF2 expression and then inhibiting the NOD-like receptor protein 3 (NLRP3)/Caspase-1/interleukin-1beta (IL-1ß) signaling pathway. Furthermore, histone deacetylase (HDAC) overexpression and molecular docking analysis results showed that TSD upregulated KLF2 expression by inhibiting HDAC 4, 5, and 7 activities. Taken together, TSD was isolated from the fermentation of Streptomyces sp. CPCC203909 and first reported as a potential activator of KLF2 in this study. Furthermore, TSD upregulated KLF2 expression by inhibiting HDAC 4, 5, and 7 and attenuated endothelial inflammation via regulation of the KLF2/NLRP3/Caspase-1/IL-1ß signaling pathway.

Innovative signature establishment using lymphangiogenesis-related lncRNA pairs to predict prognosis of hepatocellular carcinoma.

Aims: Hepatocellular carcinoma (HCC) remains a major tumoral burden globally, and its heterogeneity encumbers prognostic prediction. The lymphangiogenesis-related long non-coding RNAs (lrlncRNAs) reported to be implicated in immune response regulation show potential importance in predicting the prognostic and therapeutic outcome. Hence, this study aims to establish a lrlncRNA pairs-based signature not requiring specific expression levels of transcripts, which displays promising clinical practicality and satisfactory predictive capability. Main methods: Transcriptomic and clinical information of the Liver Hepatocellular Carcinoma (LIHC) project retrieved from the TCGA portal were used to find differently expressed lrlncRNA (DElrlncRNA) via analysis performed between lymphangiogenesis-related genes (lr-genes) and lncRNAs(lrlncRNA), and to ultimately construct the signature based on lrlncRNA pairs screened out via Lasso and Cox regression analyses. Akaike information criterion (AIC) values were computed to find the cut-off point optimum for high-risk and low-risk group allocation. The signature then underwent trials in terms of its predictive value for survival, clinicopathological features, immune cells infiltration in tumoral microenvironment, selected checkpoint biomarkers and chemosensitivity. Key findings: A novel lymphangiogenesis-related lncRNA pair signature was established using nine lrlncRNA pairs identified and significantly related to overall survival, clinicopathological features, immune cells infiltration and susceptibility to chemotherapy. Moreover, the signature efficacy was verified in acknowledged clinicopathological subgroups and partially validated by qRT-PCR assay in various human HCC cell lines. Significance: The novel lrlncRNA-pairs based signature was shown to effectively and independently estimate HCC prognosis and help screen patients suitable for anti-tumor immunotherapy and chemotherapy.

Licorice extract ameliorates hyperglycemia through reshaping gut microbiota structure and inhibiting TLR4/NF-κB signaling pathway in type 2 diabetic mice.

Previous studies suggested that licorice possessed hypoglycemic activity, but its anti-diabetic mechanism has not been clearly illustrated. Herein, we aimed to investigate the hypoglycemic activity and underlying hypoglycemic mechanisms of licorice extract (20, 40, and 80 mg kg-1day-1) in type 2 diabetes mice. The results showed that licorice extract could improve the levels of fasting blood glucose, insulin resistance, serum lipids, and endotoxemia-related colonic inflammation in diabetic mice in a dose-dependent manner. Western blots also suggested that a high-dose licorice extract could effectively decrease the levels of nuclear factor kappa-B (NF-κB), toll-like receptor 4 (TLR4), and tumor necrosis factor-α (TNF-α) in colon of diabetic mice. More importantly, all the doses of licorice extract reshaped the gut microbiota by decreasing the contents of Lachnospiraceae_NK4A136_group at the genus level and increasing the contents of Alloprevotella, Bacteroides, and Akkermansia, especially for the high-dose of licorice extract. These results indicated that the anti-diabetic effect of licorice extract might be attributed to the regulation of the gut microbiota and the colon TLR4/NF-κB signaling pathway in diabetic mice. Thus, licorice extract can be a promising dietary agent to improve type 2 diabetes.

Role, molecular mechanism and the potential target of breast cancer stem cells in breast cancer development.

Breast cancer (BC) is one of the most common malignant tumors in women globally, and its occurrence has surpassed lung cancer and become the biggest threat for women. At present, breast cancer treatment includes surgical resection or postoperative chemotherapy and radiotherapy. However, tumor relapse and metastasis usually lead to current therapy failure thanks to breast cancer stem cells (BCSCs)-mediated tumorigenicity and drug resistance. Drug resistance is mainly due to the long-term quiescent G0 phase, strong DNA repairability, and high expression of ABC transporter, and the tumorigenicity is reflected in the activation of various proliferation pathways related to BCSCs. Therefore, understanding the characteristics of BCSCs and their intracellular and extracellular molecular mechanisms is crucial for the development of targeted drugs for BCSCs. To this end, we discussed the latest developments in BCSCs research, focusing on the analysis of specific markers, critical signaling pathways that maintain the stemness of BCSCs，such as NOTCH, Wnt/ß-catenin, STAT3, Hedgehog, and Hippo-YAP signaling, immunomicroenviroment and summarizes targeting therapy strategies for stemness maintenance and differentiation, which provides a theoretical basis for further exploration of treating breast cancer and preventing relapse derived from BCSCs.

Targeting PI3Kγ/AKT Pathway Remodels LC3-Associated Phagocytosis Induced Immunosuppression After Radiofrequency Ablation.

Residual tumors after insufficient radiofrequency ablation (IRFA) shows accelerated progression and anti-PD-1 resistance. It is also reported that macrophages infiltrating into residual tumors leads to anti-PD-1 resistance. Elements of autophagy have been detected to conjugate LC3 to be increasingly expressed in residual tumors. The underlying mechanisms between LC3 and macrophages are aimed to be investigated, and explore further ways to enhance immunotherapy in treating residual tumors. In mice models and patients, macrophages demonstrate increased infiltration into residual tumors, especially surrounding the ablated zone. Single-cell transcriptome demonstrates enhancement of immunosuppression function in macrophages after IRFA. It is shown that macrophages engulf heat-treated cells through LC3-associated phagocytosis (LAP), enhance IL-4 mediated macrophage programming through the PI3Kγ/AKT pathway, and suppress T cell proliferation. Blockade of the PI3Kγ/AKT pathway enhances the antitumor activity of PD-1 blockades, inhibits malignant growth, and enhances survival in post-IRFA models. In conclusion, in mice models and patients, macrophages demonstrate increased infiltration around ablated zones in residual tumors. Blockade of the PI3Kγ/AKT pathway suppresses the growth of residual tumors in subcutaneous and orthotopic models. The results illustrate the translational potential of PI3Kγ inhibitors to enhance anti-PD-1 therapy for the treatment of residual tumors after IRFA.

Synthesis of N-methylpyridine-chlorofuranformamide analogs as novel OPG up-regulators and inhibitors of RANKL-induced osteoclastogenesis.

The OPG/RANKL/RANK pathway is a promising target for the design of therapeutic agents used in the treatment of osteoporosis. E09241 with an N-methylpyridine-chlorofuranformamide structural skeleton was previously identified to decrease bone loss and thus protect against osteoporosis in ovariectomized rats through increasing osteoprotegerin (OPG) expression. In this study, 36 derivatives of E09241 (3a) were prepared. The synthesis, up-regulation of OPG activities, SAR (structure-activity relationship), and cytotoxicity of these compounds are presented. Compounds with good up-regulating OPG activities could inhibit RANKL (the receptor activator of nuclear factor-kappa B ligand)-induced osteoclastogenesis in RAW264.7 cells. Particularly, compounds 3c and 3i1 significantly reduced NFATc1 and MMP-9 protein expression through inhibition of the NF-κB and MAPK pathways in RANKL induced RAW264.7 cells. In addition, compounds 3c and 3v significantly promoted osteoblast differentiation in MC3T3-E1 cells in osteogenic medium, and compounds 3c, 3v, and 3i1 obviously increased OPG protein expression and secretion in MC3T3-E1 cells. Furthermore, the pharmacokinetic profiles, acute toxicity, and hERG K+ channel effects of compounds 3a, 3c, 3e, 3v, and 3i1 were investigated. Taken together, these results indicate that N-methylpyridine-chlorofuranformamide analog 3i1 could serve as a promising lead for the development of new agents for treating osteoporosis.

Ultrasound Molecular Imaging as a Potential Non-invasive Diagnosis to Detect the Margin of Hepatocarcinoma via CSF-1R Targeting.

Though radiofrequency ablation (RFA) is considered to be an effective treatment for hepatocellular carcinoma (HCC), but more than 30% of patients may suffer insufficient RFA (IRFA), which can promote more aggressive of the residual tumor. One possible method to counter this is to accurately identify the margin of the HCC. Colony-stimulating factor 1 receptor (CSF-1R) has been found to be restrictively expressed by tumor associated macrophages (TAMs) and monocytes which more prefer to locate at the boundary of HCC. Using biotinylation method, we developed a CSF-1R-conjugated nanobubble CSF-1R (NBCSF-1R) using a thin-film hydration method for margin detection of HCC. CSF-1R expression was higher in macrophages than in HCC cell lines. Furthermore, immunofluorescence showed that CSF-1R were largely located in the margin of xenograft tumor and IFRA models. In vitro, NBCSF-1R was stable and provided a clear ultrasound image even after being stored for 6 months. In co-culture, NBCSF-1R adhered to macrophages significantly better than HCC cells (p = 0.05). In in vivo contrast-enhanced ultrasound imaging, the washout half-time of the NBCSF-1R was significantly greater than that of NBCTRL and Sonovue® (p = 0.05). The signal intensity of the tumor periphery was higher than the tumor center or non-tumor region after NBCSF-1R injection. Taken together, NBCSF-1R may potentially be used as a non-invasive diagnostic modality in the margin detection of HCC, thereby improving the efficiency of RFA. This platform may also serve as a complement method to detect residual HCC after RFA; and may also be used for targeted delivery of therapeutic drugs or genes.

Rutaecarpine derivative R3 attenuates atherosclerosis via inhibiting NLRP3 inflammasome-related inflammation and modulating cholesterol transport.

Atherosclerosis is a chronic disease characterized by lipid deposition and inflammatory response. NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome-facilitated inflammatory responses are crucial in the pathogenesis of atherosclerosis, and thus new therapeutic approaches are emerging that target NLRP3 and inflammation. Here, we explored the anti-atherosclerotic effect and mechanisms of a new rutaecarpine derivative, 5-deoxy-rutaecarpine (R3) in vitro and in vivo. R3 treatment attenuated atherosclerosis development and increased plaque stability in Apoe-/- mice fed a high-fat diet, and decreased levels of inflammatory mediators, such as interleukin-1ß, in the serum of Apoe-/- mice and in oxidized low-density lipoprotein (ox-LDL)-stimulated murine macrophages. R3 treatment inhibited NLRP3 inflammasome activation in the livers of Apoe-/- mice and ox-LDL-stimulated murine macrophages by inhibiting NF-κB and MAPK pathways. Additionally, R3 significantly decreased total cholesterol in the serum and livers of Apoe-/- mice and promoted cholesterol efflux in murine macrophages through upregulating protein expression of ATP-binding cassette subfamily A member 1 and scavenger receptor class B type I/human CD36 and lysosomal integral membrane protein-II analogous-1. Our results demonstrated that R3 prevented atherosclerotic progression via attenuating NLRP3 inflammasome-related inflammation and modulating cholesterol transport.