Danhong Injection Up-regulates miR-125b in Endothelial Exosomes and Attenuates Apoptosis in Post-Infarction Myocardium.

OBJECTIVE: To investigate the involvement of endothelial cells (ECs)-derived exosomes in the anti-apoptotic effect of Danhong Injection (DHI) and the mechanism of DHI-induced exosomal protection against postinfarction myocardial apoptosis. METHODS: A mouse permanent myocardial infarction (MI) model was established, followed by a 14-day daily treatment with DHI, DHI plus GW4869 (an exosomal inhibitor), or saline. Phosphate-buffered saline (PBS)-induced ECs-derived exosomes were isolated, analyzed by miRNA microarray and validated by droplet digital polymerase chain reaction (ddPCR). The exosomes induced by DHI (DHI-exo), PBS (PBS-exo), or DHI+GW4869 (GW-exo) were isolated and injected into the peri-infarct zone following MI. The protective effects of DHI and DHI-exo on MI hearts were measured by echocardiography, Masson's trichrome staining, and TUNEL apoptosis assay. The Western blotting and quantitative reverse transcription PCR (qRT-PCR) were used to evaluate the expression levels of miR-125b/p53-mediated pathway components, including miR-125b, p53, Bak, Bax, and caspase-3 activities. RESULTS: DHI significantly improved cardiac function and reduced infarct size in MI mice (P<0.01), which was abolished by the GW4869 intervention. DHI promoted the exosomal secretion in ECs (P<0.01). According to the results of exosomal miRNA microarray assay, 30 differentially expressed miRNAs in the DHI-exo were identified (28 up-regulated miRNAs and 2 down-regulated miRNAs). Among them, DHI significantly elevated miR-125b level in DHI-exo and DHI-treated ECs, a recognized apoptotic inhibitor impeding p53 signaling (P<0.05). Remarkably, treatment with DHI and DHI-exo attenuated apoptosis, elevated miR-125b expression level, inhibited capsase-3 activity, and down-regulated the expression levels of proapoptotic effectors (p53, Bak, and Bax) in post-MI hearts, whereas these effects were blocked by GW4869 (P<0.05 or P<0.01). CONCLUSION: DHI and DHI-induced exosomes inhibited apoptosis, promoted the miR-125b expression level, and regulated the p53 apoptotic pathway in post-infarction myocardium.

Purple tea water extract blocks RANKL-induced osteoclastogenesis through modulation of Akt/GSK3ß and Blimp1-Irf8 pathways.

A number of studies demonstrated that some tea extracts exert inhibitory effects on osteoclastogenesis induced by receptor activator of nuclear factor κB ligand (RANKL). However, the effect of purple tea, a famous tea in China, on osteoclastogenesis remains unclear. In this study, a water-based purple tea extract (PTE) was found to suppress osteoclast formation, osteoclastic resorption pit area formation, and F-actin ring formation within RANKL-stimulated bone marrow macrophages (BMMs). Furthermore, our results demonstrated that PTE could inhibit expression of master transcription factors NFATc1 and c-Fos and their target genes DC-STAMP, Ctsk, and Atp6v0d2. Western blot analysis revealed that PTE treatment led to reduced RANKL-induced phosphorylation of Akt and GSK3ß without altering transient activation of NF-κB and MAPKs (p38, JNK, ERK1/2) signaling. In addition, the results demonstrated that PTE treatment of RANKL-stimulated BMMs could down-regulate Blimp1 expression and up-regulate Irf8 expression. In summary, these results suggest that PTE treatment of RANKL-stimulated BMMs inhibited osteoclast differentiation via modulation of Blimp1-Irf8 and Akt/GSK3ß signaling pathways. Aligning with our in vitro results, in vivo PTE administration ameliorated bone loss in LPS-treated mice. Taken together, the results presented in this work suggest that PTE treatment possesses anti-osteolytic activity.

Sec-O-Glucosylhamaudol Inhibits RANKL-Induced Osteoclastogenesis by Repressing 5-LO and AKT/GSK3ß Signaling.

Sec-O-glucosylhamaudol (SOG), an active flavonoid compound derived from the root of Saposhnikovia divaricata (Turcz. ex Ledeb.) Schischk., exhibits analgesic, anti-inflammatory, and high 5-lipoxygenase (5-LO) inhibitory effects. However, its effect on osteoclastogenesis was unclear. We demonstrated that SOG markedly attenuated RANKL-induced osteoclast formation, F-actin ring formation, and mineral resorption by reducing the induction of key transcription factors NFATc1, c-Fos, and their target genes such as TRAP, CTSK, and DC-STAMP during osteoclastogenesis. Western blotting showed that SOG significantly inhibited the phosphorylation of AKT and GSK3ß at the middle-late stage of osteoclastogenesis without altering calcineurin catalytic subunit protein phosphatase-2ß-Aα expression. Moreover, GSK3ß inhibitor SB415286 partially reversed SOG-induced inhibition of osteoclastogenesis, suggesting that SOG inhibits RANKL-induced osteoclastogenesis by activating GSK3ß, at least in part. 5-LO gene silencing by small interfering RNA in mouse bone marrow macrophages markedly reduced RANKL-induced osteoclastogenesis by inhibiting NFATc1. However, it did not affect the phosphorylation of AKT or GSK3ß, indicating that SOG exerts its inhibitory effects on osteoclastogenesis by suppressing both the independent 5-LO pathway and AKT-mediated GSK3ß inactivation. In support of this, SOG significantly improved bone destruction in a lipopolysaccharide-induced mouse model of bone loss. Taken together, these results suggest a potential therapeutic effect for SOG on osteoclast-related bone lysis disease.

Danhong injection enhances angiogenesis after myocardial infarction by activating MiR-126/ERK/VEGF pathway.

BACKGROUND/AIM: Danhong injection (DHI) is a Chinese drug used for relieving cardiovascular diseases. This study aimed to identify the effect and mechanism of action of DHI on post-infarct angiogenesis, especially the epigenetic regulation of angiogenesis. METHODS: A myocardial infarction (MI) mouse model was induced by ligating the left anterior descending coronary artery. A 4-week daily treatment with or without DHI via intraperitoneal injection was started immediately following MI. The changes in cardiac function, pathology, and angiogenesis following MI were measured by echocardiography and immunostaining. Matrigel tube formation and scratch wound assays were used to evaluate the effect of DHI on the proliferation and migration of hypoxic human umbilical vein endothelial cells (HUVECs). The expression of miR-126, Spred-1, and angiogenesis-related mRNAs was measured by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of related proteins and the phosphorylated levels of extracellular signal-regulated kinase (ERK) and protein kinase B were detected by Western blot analysis. The loss-of-function study was performed using antagomir-126. RESULTS: The DHI-treated mice had significantly reduced infarct area, improved ejection fraction, and increased capillary density 4 weeks after MI. Also, DHI promoted the proliferation and migration of hypoxic HUVECs. The qRT-PCR and Western blot analysis revealed that DHI intervention upregulated miR-126, suppressed Spred-1 expression, and activated the ERK pathway, but not the Akt pathway. The loss-of-function study showed the blockade of the pro-angiogenic effect of DHI by antagomir-126 involving the ERK/vascular endothelial growth factor (VEGF) pathway. CONCLUSION: DHI enhanced post-infarct angiogenesis after MI by activating the miR-126/ERK/VEGF pathway.

[Effects of some active ingredients of Chinese drugs for activating blood circulation and detoxicating on blood lipids and atherosclerotic plaque inflammatory reaction in ApoE-gene knockout mice].

OBJECTIVE: To observe the effects of active ingredients from Chinese drugs for activating blood circulation and detoxicating, including notoginseng saponins (drug 1), Coptis chinensis (drug 2), giant knotweed rhizome (drug 3) and rhubarb (drug 4), on blood lipids and inflammatory reaction of aortic atherosclerotic plaques in ApoE knockout mice. METHODS: ApoE knockout mice were fed with high-fat diet for 26 weeks, then they were randomized into 6 groups, the untreated model group and the test groups treated with various test drugs respectively. After ending the 13 weeks of treatment, all the mice were sacrificed with their blood lipids detected, and their heart and aorta were taken out to make slices with paraffin embedding. Four sections from aortic root of each mouse were chosen to measure and calculate the percentage of lipid core (LC) in the total area of plaque (TP) and the lipid/collagen ratio (L/C) in the plaque by HE and Movat staining respectively, and the mean value of the four sections was taken for analysis. The expressions of granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor-alpha (TNF-alpha) in mice's aorta root were determined by immunohistochemical staining as well. RESULTS: After being treated for 13 weeks, either the percentage of LC in TP and the L/C ratio was significantly lower in all the test drug treated groups than those in the model group, respectively (P < 0.01), especially prominent in the group treated with drug 3. Although lowering of the two indexes presented in all the 3 groups treated by drug 1, 2 and 3, significant difference still presented between drug 3 treated group vs drug 1 and 2 treated group (P < 0.05). As for the expressions of GM-CSF and TNF-alpha, in comparing with the untreated model group, significant decreasing of the TNF-alpha showed only in the drug 4 treated group, while that of GM-CSF could be found in all the test drug treated groups (P < 0.05). CONCLUSION: All the 4 drugs tested in the recommended dosage can stabilize the vulnerable plaques in ApoE knockout mice by improving the constitution of plaque, among them, drug 3 and 4, the drugs possess both the actions of activating blood circulation and detoxicating, show more significant effect, and their mechanisms may be related to their actions in regulating lipid metabolism and inhibiting inflammatory reaction.