Ferrostatin-1 suppresses cardiomyocyte ferroptosis after myocardial infarction by activating Nrf2 signaling.

OBJECTIVES: Ferroptosis, a new regulated cell death pathway, plays a crucial part in the development of cardiovascular disease. However, the precise underlying mechanism remains unclear. Therefore, this study aimed to elucidate this. METHODS: Herein, an erastin-induced H9C2 cell ferroptosis in vitro model and a myocardial infarction murine model, which was created by ligating the left anterior descending coronary artery, were established. Ferroptosis-related indicators, myocardial injury-related indicators, and Nrf2 signaling-related proteins expression were analyzed to explore the potential mechanism underlying cardiomyocyte ferroptosis-mediated cardiovascular disease development. RESULTS: We demonstrated that Nrf2 downregulation in myocardial tissue, accompanied by ferroptotic events and changes in xCT and GPX4 expressions, induced cardiomyocyte ferroptosis and myocardial injury after myocardial infarction. These events, including ferroptosis and changes in Nrf2, xCT, and GPX4 expressions, were improved by ferrostatin-1 in vivo and in vitro. Besides, Nrf2 deficiency or inhibition aggravated myocardial infarction-induced cardiomyocyte ferroptosis by decreasing xCT and GPX4 expressions in vivo and in vitro. Moreover, ferrostatin-1 directly targeted Nrf2, as evidenced by surface plasmon resonance analysis. CONCLUSIONS: These results indicated that myocardial infarction is accompanied by cardiomyocyte ferroptosis and that Nrf2 signaling plays a crucial part in regulating cardiomyocyte ferroptosis after myocardial infarction.

Corrigendum to "Ginsenoside Ro, an oleanolic saponin of Panax ginseng, exerts anti-inflammatory effect by direct inhibiting toll like receptor 4 signaling pathway" [J Ginseng Res 46 (2022) 156-166].

[This corrects the article DOI: 10.1016/j.jgr.2021.05.011.].

10-Gingerol, a natural AMPK agonist, suppresses neointimal hyperplasia and inhibits vascular smooth muscle cell proliferation.

Background: Abnormal proliferation of vascular smooth muscle cells (VSMCs) in the intimal region is a key event in the development of neointimal hyperplasia. 10-G, a bioactive compound found in ginger, exerted inhibitory effects on the proliferation of several cancer cells. However, the effect and mechanism of 10-G on neointimal hyperplasia are not clear. Purpose: To explore the suppressive effects of 10-G on the proliferation and migration of VSMCs, and investigate the underlying mechanisms. Methods: In vivo, a left common carotid artery ligation mouse model was used to observe the effects of neointimal formation through immunohistochemistry and hematoxylin-eosin staining. In vitro, the cell proliferation and migration of HASMCs and A7r5 cells were detected by MTS assay, EdU staining, wound healing assay, Transwell assay, and western blotting as well. Molecular docking, molecular dynamics simulations and surface plasmon resonance imaging were collectively used to evaluate the interaction of 10-G with AMP-activated protein kinase (AMPK). Compound C and si-AMPK were used to inhibit the expression of AMPK. Results: Treatment with 10-G significantly reduced neointimal hyperplasia in the left common carotid artery ligation mouse model. MST and EdU staining showed that 10-G inhibited the proliferation of VSMC cells A7r5 and HASMC. We also found that 10-G altered the expression of proliferation-related proteins, including CyclinD1, CyclinD2, CyclinD3, and CDK4. Molecular docking revealed that the binding energy between AMPK and 10-G is -7.4 kcal mol-1. Molecular simulations suggested that the binding between 10-G and AMPK is stable. Surface plasmon resonance imaging analysis also showed that 10-G has a strong binding affinity to AMPK (KD = 6.81 × 10-8 M). 10-G promoted AMPKα phosphorylation both in vivo and in vitro. Blocking AMPK by an siRNA or AMPK inhibitor pathway partly abolished the anti-proliferation effects of 10-G on VSMCs. Conclusion: These data showed that 10-G might inhibit neointimal hyperplasia and suppress VSMC proliferation by the activation of AMPK as a natural AMPK agonist.

Ginsenoside Ro, an oleanolic saponin of Panax ginseng, exerts anti-inflammatory effect by direct inhibiting toll like receptor 4 signaling pathway.

BACKGROUND: Panax ginseng Meyer (P. ginseng), a herb distributed in Korea, China and Japan, exerts benefits on diverse inflammatory conditions. However, the underlying mechanism and active ingredients remains largely unclear. Herein, we aimed to explore the active ingredients of P. ginseng against inflammation and elucidate underlying mechanisms. METHODS: Inflammation model was constructed by lipopolysaccharide (LPS) in C57BL/6 mice and RAW264.7 macrophages. Molecular docking, molecular dynamics, surface plasmon resonance imaging (SPRi) and immunofluorescence were utilized to predict active component. RESULTS: P. ginseng significantly inhibited LPS-induced lung injury and the expression of pro-inflammatory factors, including TNF-α, IL-6 and IL-1ß. Additionally, P. ginseng blocked fluorescence-labeled LPS (LPS488) binding to the membranes of RAW264.7 macrophages, the phosphorylation of nuclear factor-κB (NF-κB) and mitogen-activated protein kinases (MAPKs). Furthermore, molecular docking demonstrated that ginsenoside Ro (GRo) docked into the LPS binding site of toll like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD2) complex. Molecular dynamic simulations showed that the MD2-GRo binding conformation was stable. SPRi demonstrated an excellent interaction between TLR4/MD2 complex and GRo (KD value of 1.16 × 10-9 M). GRo significantly inhibited LPS488 binding to cell membranes. Further studies showed that GRo markedly suppressed LPS-triggered lung injury, the transcription and secretion levels of TNF-α, IL-6 and IL-1ß. Moreover, the phosphorylation of NF-κB and MAPKs as well as the p65 subunit nuclear translocation were inhibited by GRo dose-dependently. CONCLUSION: Our results suggest that GRo exerts anti-inflammation actions by direct inhibition of TLR4 signaling pathway.

Dihydrotanshinone I inhibits the growth of hepatoma cells by direct inhibition of Src.

BACKGROUND: Liver cancer is one of the leading causes of cancer-related death worldwide. Dihydrotanshinone I (DHI) was shown to inhibit the growth of several types of cancer. However, research related to hepatoma treatment using DHI is limited. PURPOSE: Here, we explored the inhibitory effect of DHI on the growth of hepatoma cells, and investigated the underlying molecular mechanisms. METHODS: The proliferation of Hep3B, SMCC-7721 and SK-Hep1 hepatoma cells was evaluated using the MTS and Edu staining assay. Hepatoma cell death was analyzed with a LIVE/DEAD Cell Imaging Kit. The relative expression and phosphorylation of proto-oncogene tyrosine-protein kinase Src (Src) and signal transducer and activator of transcription-3 (STAT3) proteins in hepatoma cells, as well as the expression of other protein components, were measured by western blotting. The structural interaction of DHI with Src proteins was evaluated by molecular docking, molecular dynamics simulation, surface plasmon resonance imaging and Src kinase inhibition assay. Src overexpression was achieved by infection with an adenovirus vector encoding human Src. Subsequently, the effects of DHI on tumor growth inhibition were further validated using mouse xenograft models of hepatoma. RESULTS: In vitro studies showed that treatment with DHI inhibited the proliferation and promoted cell death of Hep3B, SMCC-7721 and SK-Hep1 hepatoma cells. We further identified and verified Src as a direct target of DHI by using molecular stimulation, surface plasmon resonance image and Src kinase inhibition assay. Treatment with DHI reduced the in vitro phosphorylation levels of Src and STAT3, a transcription factor regulated by Src. In the xenograft mouse models, DHI dose-dependently suppressed tumor growth and Src and STAT3 phosphorylation. Moreover, Src overexpression partly abrogated the inhibitory effects of DHI on the proliferation and cell death in hepatoma cells. CONCLUSION: Our results suggest that DHI inhibits the growth of hepatoma cells by direct inhibition of Src.

Tanshinone I Inhibits Oxidative Stress-Induced Cardiomyocyte Injury by Modulating Nrf2 Signaling.

Cardiovascular disease, a disease caused by many pathogenic factors, is one of the most common causes of death worldwide, and oxidative stress plays a major role in its pathophysiology. Tanshinone I (Tan I), a natural compound with cardiovascular protective effects, is one of the main active compounds extracted from Salvia miltiorrhiza. Here, we investigated whether Tan I could attenuate oxidative stress and oxidative stress-induced cardiomyocyte apoptosis through Nrf2/MAPK signaling in vivo and in vitro. We found that Tan I treatment protected cardiomyocytes against oxidative stress and oxidative stress-induced apoptosis, based on the detection of relevant oxidation indexes such as reactive oxygen species, superoxide dismutase, malondialdehyde, and apoptosis, including cell viability and apoptosis-related protein expression. We further examined the mechanisms underlying these effects, determining that Tan I activated nuclear factor erythroid 2 (NFE2)-related factor 2 (Nrf2) transcription into the nucleus and dose-dependently promoted the expression of Nrf2, while inhibiting MAPK signaling activation, including P38 MAPK, SAPK/JNK, and ERK1/2. Nrf2 inhibitors in H9C2 cells and Nrf2 knockout mice demonstrated aggravated oxidative stress and oxidative stress-induced cardiomyocyte injury; Tan I treatment suppressed these effects in H9C2 cells; however, its protective effect was inhibited in Nrf2 knockout mice. Additionally, the analysis of surface plasmon resonance demonstrated that Tan I could directly target Nrf2 and act as a potential Nrf2 agonist. Collectively, these data strongly indicated that Tan I might inhibit oxidative stress and oxidative stress-induced cardiomyocyte injury through modulation of Nrf2 signaling, thus supporting the potential therapeutic application of Tan I for oxidative stress-induced CVDs.

Effects and mechanism of action of Huang-Lian-Jie-Du-Tang in atopic dermatitis-like skin dysfunction in vivo and in vitro.

ETHNOPHARMACOLOGICAL RELEVANCE: Atopic dermatitis (AD), a disorder prevalent during childhood and adulthood, seriously affects the patient's quality of life. Although Huang-Lian-Jie-Du-Tang (HLJDT) has shown anti-inflammatory effects in previous studies, its effects and mechanism of action underlying AD disorder are still largely unknown. OBJECTIVE: This study explored the anti-inflammatory and immunomodulatory effects of HLJDT on the AD-like dermal disorder, induced in vitro by lipopolysaccharide (LPS)-triggered inflammation, and in vivo by 2,4-dinitrochlorobenzene (DNCB). MATERIALS AND METHODS: In vivo HLJDT effects were investigated by determining the severity of dermatitis, which consisted of observing signs of skin lesions, visually and through haematoxylin and eosin (HE) staining, in mouse ears and dorsal skin, measuring serum levels of interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-5, IL-6, interferon (IFN)-γ, the tumour necrosis factor (TNF)-α, and determining the splenic index, number of splenic CD4+/CD8+ T-lymphocytes, as well as the phosphorylation levels of mitogen-activated protein kinases (including MAPKs-p38, ERK, and JNK), IκB-α, and nuclear factor kappa B (NF-κB) (p65) within dermal lesions. Morphological changes in LPS-induced inflammation were observed under a microscope, and ELISA and qPCR assays were used to measure IL-1α, IL-1ß, IL-6, and TNF-α expression levels. The protein expression levels of P-ERK/ERK, P-p38/p38, P-JNK/JNK, P-IKß-α, and P-p65 were measured through western blotting. Additionally, p65 expression was assessed by immunofluorescence, and LPS binding to RAW264.7 cell membrane was studied with laser confocal microscopy. RESULTS: HLJDT could remarkably mitigate DNCB-induced AD-like lesion symptoms, alleviating inflammatory mediator infiltration in mouse ears and dorsal skin tissue, down-regulating serum expression levels of IL-1α, IL-1ß, IL-2, IL-4, IL-5, IL-6, IFN-γ, and TNF-α, normalising the splenic CD4+/CD8+ T-lymphocyte ratio, and inactivating MAPKs (including p38, ERK, and JNK), IκB-α, and NF-κB (p65) in dorsal skin. Furthermore, HLJDT inhibited LPS-induced differentiation of RAW264.7 cells, as evidenced by the decreased protein and mRNA expression of IL-1α, IL-1ß, IL-6, and TNF-α. Additionally, it decreased ERK, p38, JNK, IKß-α, and p65 phosphorylation levels in the MAPKs/NF-κB pathway, inhibited p65 nuclear translocation, and reduced LPS binding to the RAW264.7 cell membrane. CONCLUSIONS: HLJDT significantly improved AD-like symptoms via inhibition of the MAPKs/NF-κB pathway. Therefore, administration of HLJDT might be a potential treatment for AD in the clinical setting.

Tanshinone I inhibits vascular smooth muscle cell proliferation by targeting insulin-like growth factor-1 receptor/phosphatidylinositol-3-kinase signaling pathway.

Vascular smooth muscle cell (VSMC) proliferation plays a critical role in arterial remodeling during various vascular diseases including atherosclerosis and hypertension. Tanshinone I, a major component of Salvia miltiorrhiza, exerts protective effects against cardiovascular diseases. In this study, we investigated the effects of tanshinone I on VSMC proliferation, as well as the underlying mechanisms. We found that this compound inhibited the proliferation of VSMCs in a dose-dependent manner, based on 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) and 5-ethynyl-2'-deoxyuridine (EdU) assays. Western blotting demonstrated that tanshinone I inhibited the expression of proliferation-related proteins, including cyclin-dependent kinase 4 (CDK4), cyclin D3, and cyclin D1, in a dose-dependent manner. Molecular docking showed that this compound docked to the inhibitor-binding site of the insulin-like growth factor 1 (IGF-1) receptor (IGF-1R), and the binding energy between tanshinone I and IGF-1R was -9.021 kcal/mol. Molecular dynamic simulations showed that the IGF-1R-tanshinone I binding was stable. We also found that tanshinone I dose-dependently inhibited IGF-1R activation and its downstream molecules, insulin receptor substrate (IRS)-1, phosphatidylinositol-3-Kinase (PI3K), Akt, glycogen synthase kinase-3 beta (GSK3ß), mammalian target of rapamycin (mTOR), 70S6K, and ribosomal protein S6 (RPS6). Notably, activation of IGF-1R by recombinant IGF-1 rescued the activity of IGF-1R and its downstream molecules, and the proliferation of tanshinone I-treated VSMC. In addition, blocking PI3K signaling with LY294002 showed the important role of this pathway in tanshinone I-mediated suppression of VSMC proliferation. Collectively, these data demonstrated that tanshinone I might inhibit VSMC proliferation by inhibiting IGF-1R/PI3K signaling.

Rheum palmatum extract exerts anti-hepatocellular carcinoma effects by inhibiting signal transducer and activator of transcription 3 signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Hepatocellular carcinoma (HCC) is among the most common malignancies. Signal transducer and activator of transcription 3 (STAT3), with abnormal expression and constitutive activation, has been reported to promote proliferation, metastasis, survival and angiogenesis of HCC cells. Rheum palmatum (RP), a traditional Chinese medicinal herb, exhibited tumor-suppressing effects in multiple human cancers, but its potential functions in HCC remain unexplored. AIM OF THE STUDY: This study aimed to examine the involvement of STAT3 signaling in the anti-HCC effects of RP extract. MATERIALS AND METHODS: SMMC-7721 and HepG2 HCC cell lines were treated with RP extract for 24 h, and then viability, migration, and invasion of HCC cells and angiogenesis of human umbilical vein endothelial cells (HUVECs) were analyzed using MTS, wound-healing, Transwell invasion and tube formation assays, respectively. Western blotting and immunohistochemistry (IHC) were used to examine the activation of key molecules in STAT3 signaling, including STAT3, JAK2, and Src. Additionally, we explored the in vivo antitumor effects of RP extract in a xenograft tumor nude mouse model of HCC. RESULTS: The result showed that RP extract reduced viability, migration, and invasion of SMMC-7721 and HepG2 cells and angiogenesis of HUVECs. It suppressed the phosphorylation of STAT3 and its upstream kinases including JAK2 and Src. In addition, RP extract treatment downregulated STAT3 target genes, including survivin, Bcl-xL, Mcl-1, Bcl-2, MMP-2, MMP-9, Cyclin D1, CDK4, c-Myc, and VEGF-C. Furthermore, RP extract suppressed the xenograft tumor growth and activation of STAT3 in xenograft tumor mice. CONCLUSION: Collectively, the results showed that RP extract prevented HCC progression by inhibiting STAT3, and might be useful for the treatment of HCC.

Change of intestinal flora and its relationship with IL-23/IL-17 axis in pa-tients with ulcerative colitis / 中国病理生理杂志

AIM:To investigate the change of intestinal flora distribution and its relationship with interleukin -23(IL-23)/IL-17 axis in ulcerative colitis(UC)patients.METHODS:The fresh fecal samples from 20 patients with ac-tive UC and 20 healthy controls were collected.The distribution of the flora was analyzed by direct smear and traditional bacterial culture.The changes of bacteria were detected by real-time PCR.The hemoglobin,albumin,erythrocyte sedimen-tation,and C-reactive protein levels were tested routinely.Both normal and damaged mucosal tissues of UC patients were examined and obtained by colonoscopy,and further assessed by Mayo scoring,Baron grading and HE staining.The expres-sion of IL-17 and IL-23 was observed by immunohistochemistry and Western blot.RESULTS:(1)The degree of flora im-balance in active UC patients was higher than that in the healthy controls(P<0.05).(2)The results of aerobic culture showed that the number of Escherichia coli in the UC patients was significantly lower than that in the normal controls(P<0.01),while Enterococcus was increased obviously(P<0.01).The results of anaerobic culture revealed that the numbers of Bacteroidetes,Bifidobacterium bifidum and Lactobacilli in the UC patients were significantly decreased(P<0.01).(3) Quantitative analysis of target bacteria showed that the relative quantification of Escherichia coli,Bacteroidetes,Bifidobacte-rium bifidum and Lactobacilli in the UC patients was significantly lower than that in the normal subjects,and the number of Enterococcus was significantly increased(P<0.01).(4)Compared with control group,no significant change of hemoglo-bin in the UC patients was ovserved,albumin was significantly decreased(P<0.05), but erythrocyte sedimentation and C-reactive protein levels were elevated obviously(P<0.01).(5)The Mayo score, Baron grade, and histopathological score were all increased(P<0.01).(6)High IL-17 and IL-23 expression levels were detected in the UC patients(P<0.01).(7)Correlation analysis showed that the average absorbance values of IL -17 and IL-23 expression were positively correlated with Baron grade(r=0.717,P=0.02;r=0.849,P=0.016)and pathological score(r=0.660, P=0.03;r=0.675,P=0.032).Meanwhile, the average absorbance value of IL-23 expression was negatively correlated with the number of Escherichia coli(r =-0.699, P =0.025), and positively correlated with Enterococcus(r =0.872, P =0.010).Furthermore,the average absorbance value of IL-17 expression was positively correlated with Enterococcus(r=0.764,P=0.046),and both of them were not correlated with other bacteria.CONCLUSION: Obvious flora imbalance exists in active UC patients,changed intestinal microflora is closely related with the degree of inflammation.IL-23/IL-17 axis,as a key factor in the development of UC,may be related to the changes of intestinal microflora.The interaction be-tween intestinal microflora and IL-23/IL-17 axis plays an important role in the pathogenesis of UC.