Effects of Scutellaria baicalensis Georgi on Macrophage-Hepatocyte Interaction Through Cytokines Related to Growth Control of Murine Hepatocytes

Targets and Potential Mechanism of Scutellaria baicalensis in Treatment of Primary Hepatocellular Carcinoma Based on Bioinformatics Analysis

Objective

To analyze the target and potential mechanism of Scutellaria baicalensis (SB) in the treatment of HCC based on bioinformatics, so as to provide suggestions for the diagnosis, treatment, and drug development of hepatocellular carcinoma (HCC).

Methods

The regulated gene targets of SB were screened by gene expression pattern clustering and differential analysis of gene expression data of HepG2 cells treated with SB at 0 h, 1 h, 3 h, 6 h, 12 h, and 24 h. The module genes related to HCC were identified by the weighted gene coexpression network analysis (WGCNA). KEGG and GO enrichment were used to analyze the molecular function and structure of the module, and GSEA was used to evaluate the different functional pathways between normal people and patients with HCC. Then, the module gene was used for univariate Cox proportional hazard analysis and the least absolute shrinkage and selection operator (LASSO) Cox regression analysis to build a prognostic model. The protein-protein interaction network (PPI) was used to analyze the core genes regulated by SB (CGRSB) of the module, and the survival curve revealed the CGRSB impact on patient survival. The CIBERSORT algorithm combined with correlation analysis to explore the relationship between CGRSB and immune infiltration. Finally, the single-cell sequencing technique was used to analyze the distribution of CGRSB at the cellular level.

Results

SB could regulate 903 genes, of which 234 were related to the occurrence of HCC. The prognosis model constructed by these genes has a good effect in evaluating the survival of patients. KEGG and GO enrichment analysis showed that the regulation of SB on HCC mainly focused on some cell proliferation, apoptosis, and immune-related functions. GSEA enrichment analysis showed that these functions are related to the occurrence of HCC. A total of 24 CGRSB were obtained after screening, of which 13 were significantly related to survival, and most of them were unfavorable factors for patient survival. The correlation analysis of gene expression showed that most of CGRSB was significantly correlated with T cells, macrophages, and other functions. The results of single-cell analysis showed that the distribution of CGRSB in macrophages was the most.

Conclusion

SB has high credibility in the treatment of HCC, such as CDK2, AURKB, RRM2, CENPE, ESR1, and PRIM2. These targets can be used as potential biomarkers for clinical diagnosis. The research also shows that the p53 signal pathway, MAPK signal pathway, apoptosis pathway, T cell receptor pathway, and macrophage-mediated tumor immunity play the most important role in the mechanism of SB in treating HCC.

Baicalin attenuates lipopolysaccharide-induced pro-inflammatory cytokine expression in murine macrophage cell line RAW264.7 through miR-124-STAT3 axis

Baicalin, a flavonoid isolated from Scutellaria baicalensis Georgi, has shown a wide range of anti-inflammatory, antioxidative, antiviral, and antitumor properties. However, the molecular mechanism of how baicalin exerts its effects, especially on inflammation regulation, has not been fully investigated. In this article, we report the effects of baicalin on the mouse macrophage cell line RAW264.7. Our results demonstrate that baicalin inhibits the production of inflammatory factors interleukin-6 and tumor necrosis factor-alpha upon lipopolysaccharide stimulation of macrophages. We observed that baicalin inhibits STAT3 activation through retarding its expression and phosphorylation. Interestingly, baicalin treatment promotes the elevation of miR-124 in lipopolysaccharide-treated macrophages. Overexpression of the miR-124 mimic in RAW264.7 reduced STAT3 expression and phosphorylation. Furthermore, inhibition of miR-124 attenuated the dysregulation of STAT3 and reduction of inflammatory factors upon baicalin treatment. Our results revealed the molecular mechanism that baicalin attenuates pro-inflammatory cytokine production through miR-124-STAT3 signaling pathway, suggesting that miR-124 is an important modulator in regulating anti-inflammation by baicalin in macrophages.

Herb-induced autoimmune-like hepatitis in C57BL/6J mice

BACKGROUND & AIMS

Animal model suitable for studying herb-induced experimental autoimmune hepatitis (AIH) remains a challenging problem. A medicinal herb containing Scutellaria baicalensis Georgi (Sb) and Bupleurum chinense DC (Bc) has been sporadically reported to be related to liver fibrosis. The aim of this study was to investigate the effects of Sb and Bc on experimental AIH in mice.

METHODS

C57BL/6J mice received intraperitoneal injection of Sb and/or Bc herbal extracts (1 mg/kg) for 4 or 8 weeks. Serum samples were collected to analyse serum transferase (AST, ALT), creatinine, markers for AIH and hepatic cytokine levels such as IFN-γ, IL10 and TGF-β1. Peripheral mononuclear cell (PBMC) gene expression profiles were analysed to show their effects on immune system.

RESULTS

Our results showed that Sb or Bc treatment increased serum AST, ALT, IgG and ANA levels. Prominent necroinflammatory changes were demonstrated in the livers of Sb- or Bc-treated mice while the decrease in IFN-γ and elevation of IL10 and TGF-β1 levels in liver tissues. Furthermore, the PMBC gene expression profile suggested that Sb or Bc treatment could modulate immune responses.

CONCLUSION

We conclude that the presence of AIH in Sb- or Bc-treated mice and C57BL/6J strain mice is a reliable animal model for studying herb-induced AIH-like hepatitis.

Effects of S/B remedy containing Scutellaria baicalensis and Bupleurum scorzonerifolfium on hepatic interleukin-6 related signal transducer and activator of transcription 3 activation in mice through cell-cell interaction

Signal transducer and activator of transcription 3 (STAT3) plays an important role in regulating interleukin 6 (IL-6) related growth control of the liver. Our previous study demonstrated that a mixture containing Scutellaria baicalensis and Bupleurum scorzonerifolfium (S/B remedy) modulated the growth of hepatocytes during liver regeneration after 2/3 partial hepatectomy. The aim of this study was to investigate whether S/B remedy induced mouse hepatic STAT3 activation directly in hepatocytes or indirectly via non-parenchymal cell-hepatocyte interaction. Direct S/B remedy effects were studied using primarily isolated hepatocytes; while C57BL/6J mice were used to study indirect effects of S/B remedy using gadolinium chloride to deplete Kupffer cells' function. The results showed that S/B remedy and its active constituents did not directly activate growth-related signaling in primarily isolated hepatocytes. However, S/B remedy induced STAT3 and subsequently suppressor of cytokine signaling (SOCS3) activation in mouse liver and increased serum IL-6 level in a dose-dependent manner, which could be partially blocked by pretreatment with gadolinium chloride. Oligonucloetide microarray analysis from S/B remedy-treated peripheral blood leukocytes demonstrated an up-regulation of IL-6 gene expression. We conclude that S/B remedy did not directly induce STAT3 activation in vitro, but induced hepatic IL-6 related STAT3 activation through non-parenchymal cell-hepatocyte interaction in vivo. The results provide important information on the molecular mechanisms of S/B remedy for treatment of human liver diseases.

Baicalin inhibits PDGF-BB-stimulated vascular smooth muscle cell proliferation through suppressing PDGFRβ-ERK signaling and increase in p27 accumulation and prevents injury-induced neointimal hyperplasia

The increased proliferation and migration of vascular smooth muscle cells (VSMCs) are key events in the development of atherosclerotic lesions. Baicalin, an herb-derived flavonoid compound, has been previously shown to induce apoptosis and growth inhibition in cancer cells through multiple pathways. However, the potential role of baicalin in regulation of VSMC proliferation and prevention of cardiovascular diseases remains unexplored. In this study, we show that pretreatment with baicalin has a dose-dependent inhibitory effect on PDGF-BB-stimulated VSMC proliferation, accompanied with the reduction of proliferating cell nuclear antigen (PCNA) expression. We also show that baicalin-induced growth inhibition is associated with a decrease in cyclin E-CDK2 activation and increase in p27 level in PDGF-stimulated VSMCs, which appears to be at least partly mediated by blockade of PDGF receptor β (PDGFRβ)-extracellular signal-regulated kinase 1/2 (ERK1/2) signaling. In addition, baicalin was also found to inhibit adhesion molecule expression and cell migration induced by PDGF-BB in VSMCs. Furthermore, using an animal carotid arterial balloon-injury model, we found that baicalin significantly inhibited neointimal hyperplasia. Taken together, our results reveal a novel function of baicalin in inducing growth arrest of PDGF-stimulated VSMCs and suppressing neointimal hyperplasia after balloon injury, and suggest that the underlying mechanism involves the inhibition of cyclin E-CDK2 activation and the increase in p27 accumulation via blockade of the PDGFRβ-ERK1/2 signaling cascade.

Neferine, a bisbenzylisoquinline alkaloid attenuates bleomycin-induced pulmonary fibrosis

In this study, we evaluated the potential anti-fibrotic property of neferine, a bisbenzylisoquinline alkaloid extracted from the seed embryo of Nelumbo mucifera Gaertn. Intratracheal bleomycin administration resulted in pulmonary fibrosis 14 and 21 days posttreatment, as evidenced by increased hydroxyproline content in bleomycin group (255.77+/-97.17 microg/lung and 269.74+/-40.92 microg/lung) compared to sham group (170.78+/-76.46 microg/lung and 191.24+/-60.45 microg/lung), and the hydroxyproline was significantly suppressed (193.07+/-39.55 microg/lung and 201.08+/-71.74 microg/lung) by neferine administration (20mg/kg, b.i.d). The attenuated-fibrosis condition was also validated by histological observations. Biochemical measurements revealed that bleomycin caused a significant decrease in lung superoxidae dismutase (SOD) activity, which was accompanied with a significant increase in malondialdehyde (MDA) levels and myeloperoxidase (MPO) activity on the 7th and 14th days. However, neferine reversed the decrease in SOD activity as well as the increase in MDA and MPO activity. Enzyme-linked immunosorbent assay and radio-immunity assay showed that treatment with neferine alleviated bleomycin-induced increase of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-6 and endothelin-1 in plasma or in tissue. Additionally, neferine blocked bleomycin-induced increases of NF-kappaB in nuclear extracts and TGF-beta(1) in total protein extracts of murine RAW264.7 macrophages. In summary, neferine attenuates bleomycin-induced pulmonary fibrosis in vitro and in vivo. The beneficial effect of neferine might be associated with its activities of anti-inflammation, antioxidation, cytokine and NF-kappaB inhibition.

Inhibitory effect of D1-like and D3 dopamine receptors on norepinephrine-induced proliferation in vascular smooth muscle cells

The sympathetic nervous system plays an important role in the regulation of blood pressure. There is increasing evidence for positive and negative interactions between dopamine and adrenergic receptors; the activation of the alpha-adrenergic receptor induces vasoconstriction, whereas the activation of dopamine receptor induces vasorelaxation. We hypothesize that the D1-like receptor and/or D3 receptor also inhibit alpha1-adrenergic receptor-mediated proliferation in vascular smooth muscle cells (VSMCs). In this study, VSMC proliferation was determined by measuring [3H]thymidine incorporation, cell number, and uptake of 3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide (MTT). Norepinephrine increased VSMC number and MTT uptake, as well as [3H]thymidine incorporation via the alpha1-adrenergic receptor in aortic VSMCs from Sprague-Dawley rats. The proliferative effects of norepinephrine were attenuated by the activation of D1-like receptors or D3 receptors, although a D1-like receptor agonist, fenoldopam, and a D3 receptor agonist, PD-128907, by themselves, at low concentrations, had no effect on VSMC proliferation. Simultaneous stimulation of both D1-like and D3 receptors had an additive inhibitory effect. The inhibitory effect of D3 receptor was via protein kinase A, whereas the D1-like receptor effect was via protein kinase C-zeta. The interaction between alpha1-adrenergic and dopamine receptors, especially D1-like and D3 receptors in VSMCs, could be involved in the pathogenesis of hypertension.