[Buyang Huanwu Decoction promotes arteriogenesis after hindlimb ischemia in mice by activating PDGF signaling pathway].

This study aims to investigate the effect of Buyang Huanwu Decoction on blood flow recovery and arteriogenesis after hindlimb ischemia in mice via the platelet-derived growth factor(PDGF) signaling pathway. Forty C57BL/6 mice were randomized into model(clean water, 10 mL·kg~(-1)·d~(-1)), beraprost sodium(positive control, 18 µg·kg~(-1)·d~(-1)), and low-, medium-, and high-dose(10, 20, and 40 g·kg~(-1)·d~(-1), respectively) Buyang Huanwu Decoction groups(n=8). The hindlimb ischemia model was established by femoral artery ligation. The mice were administrated with corresponding agents by gavage daily for 14 days after ligation. For laser Doppler perfusion imaging, the mice were anesthetized and measured under a Periscan PSI imager. The density of capillary and arterio-le in the ischemic gastrocnemius was measured using immunofluorescence staining of the frozen tissue sections. Western blot was employed to determine the expression of PDGF subunit B(PDGFB), phosphorylated mitogen extracellular kinase(p-MEK), MEK, phosphorylated extracellular signal-regulated kinase(p-ERK), and ERK. Real-time PCR was employed to determine the mRNA level of PDGFB. The Buyang Huanwu Decoction-containing serum was used to treat the vascular smooth muscle cells(VSMCs) in hypoxia at doses of 10% and 20%. The proliferation and migration of VSMCs was assessed in vitro. The results showed that compared with the model group, beraprost sodium and Buyang Huanwu Decoction enhanced the blood flow recovery, increased the capillary and arteriole density, and up-regulated the protein levels of PDGFB, p-MEK, p-ERK, and mRNA levels of PDGFB, with the medium-dose Buyang Huanwu Decoction demonstrating the most significant effect. The 10% Buyang Huanwu Decoction-containing serum enhanced the proliferation and migration of VSMCs. Our findings demonstrate that Buyang Huanwu Decoction up-regulates PDGFB transcription and activates PDGF signaling pathway to promote arteriogenesis and blood flow recovery in ischemic gastrocnemius.

Assessing serum levels of SM22α as a new biomarker for patients with aortic aneurysm/dissection.

BACKGROUND: Aortic aneurysm/dissection (AAD) is now encountered more often because of the increasing prevalence of atherosclerosis and hypertension in the population. Despite many therapeutic improvements, in particular timely and successful surgery, in-hospital mortality rates are still higher. Timely identification of patients at high risk will help improve the overall prognosis of AAD. Since early clinical and radiological signs are nonspecific, there is an urgent need for accurate biomarkers. Smooth muscle 22α (SM22α) is a potential marker for AAD because of its abundant expression in vascular smooth muscle, which is involved in development of AAD. METHODS: We prepared three different mouse models, including abdominal aortic aneurysm, neointimal hyperplasia and atherosclerosis. SM22α levels were assessed in serum and vascular tissue of the mice. Next, the relationships between serum SM22α level and vascular lesion were studied in mice. Finally, serum from 41 patients with AAD, 107 carotid artery stenosis (CAS) patients and 40 healthy volunteers were tested for SM22α. Serum levels of SM22α were measured using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with the controls, serum SM22α levels were reduced in the models of aortic aneurysm, neointimal formation and atherosclerosis, and elevated in mice with ruptured aneurysm. Serum SM22α level was negatively correlated with apoptosis rate of vascular smooth muscle cells (VSMC), ratio of intima/ media (I/M) area and plaque size. Patients with AAD had significantly higher serum SM22α levels than patients with only CAS, or normal controls. CONCLUSION: Serum SM22α could be a potential predictive marker for AAD, and regulation of VSMC is a possible mechanism for the effects of SM22α.

circYap inhibits oral squamous cell carcinoma by arresting cell cycle.

OBJECTIVE: Circular RNAs (circRNAs) involve in the development and progression of tumour. The mechanism of circRNAs in oral squamous cell carcinoma (OSCC) has remained unclear. This study aimed to investigate the role of circular Yes-associated protein (circYap) in OSCC. METHODS: Quantification reverse transcription-polymerase chain reaction (qRT-PCR) was applied to measure circYap expression in patients with OSCC tissues and cells. Flow cytometry was performed to evaluate cell cycle. circYap interaction with CDK4 was detected by RNA immunoprecipitation (RIP) and RNA pull-down. The interaction of Cyclin D1 and CDK4 was determined using co-immunoprecipitation (co-IP). RESULTS: We showed that circYap expression was downregulated in OSCC tissues. Using small interfering circular (Si-circYap) and overexpression plasmid, we found that circYap overexpression inhibited proliferation and arrested cell cycle in OSCC cells, while, circYap knockdown yielded the opposite result. Cyclin D1/CDK4 complexes and nuclear translocation is essential for cell cycle progression. We found that CDK4 interacted with circYap was increased when circYap overexpression, meanwhile, Cyclin D1/CDK4 complexes and of nuclear distribution were decreased. CONCLUSIONS: Our findings suggest that circYap impedes progression of OSCC. Overexpression of circYap suppresses proliferation and cell cycle through binding to CDK4 to block formation and nuclear translocation of Cyclin D1/CDK4 complexes. Thus, circYap may serves as a valuable therapeutic target for OSCC.

Smooth muscle 22 alpha protein inhibits VSMC foam cell formation by supporting normal LXRα signaling, ameliorating atherosclerosis.

Vascular smooth muscle cells (VSMCs) are indispensable components in foam cell formation in atherosclerosis. However, the mechanism behind foam cell formation of VSMCs has not been addressed. We found a potential association between deletion of smooth muscle (SM) 22α and deregulated nuclear receptors liver X receptors (LXRs)/retinoid X receptor (RXR) signaling in mice. Here, we investigated the roles of SM22α in LXRα-modulated cholesterol homeostasis, and explore possible mechanisms underlying this process. We identified that the depletion of SM22α was a primary event driving VSMC cholesterol accumulation and the development of atherosclerosis in mice. Proteomic and lipidomic analysis validated that downregulation of SM22α was correlated with reduced expression of LXRα and ATP-binding cassette transporter (ABCA) 1 and increased cholesteryl ester in phenotypically modulated VSMCs induced by platelets-derived growth factor (PDGF)-BB. Notably, LXRα was mainly distributed in the cytoplasm rather than the nucleus in the neointimal and Sm22α-/- VSMCs. Loss of SM22α inhibited the nuclear import of LXRα and reduced ABCA1-mediated cholesterol efflux via promoting depolymerization of actin stress fibers. Affinity purification and mass spectrometry (AP-MS) analysis, co-immunoprecipitation and GST pull-down assays, confocal microscopy, and stochastic optical reconstruction microscopy (STORM) revealed that globular-actin (G-actin), monomeric actin, interacted with and retained LXRα in the cytoplasm in PDGF-BB-treated and Sm22α-/- VSMCs. This interaction blocked LXRα binding to Importin α, a karyopherin that mediates the trafficking of macromolecules across the nuclear envelope, and the resulting reduction of LXRα transcriptional activity. Increasing SM22α expression restored nuclear localization of LXRα and removed cholesterol accumulation via inducing actin polymerization, ameliorating atherosclerosis. Our findings highlight that LXRα is a mechanosensitive nuclear receptor and that the nuclear import of LXRα maintained by the SM22α-actin axis is a potential target for blockade of VSMC foam cell formation and development of anti-atherosclerosis.

SM22α Loss Contributes to Apoptosis of Vascular Smooth Muscle Cells via Macrophage-Derived circRasGEF1B.

Vascular smooth muscle cell (VSMC) apoptosis is a major defining feature of abdominal aortic aneurysm (AAA) and mainly caused by inflammatory cell infiltration. Smooth muscle (SM) 22α prevents AAA formation through suppressing NF-κB activation. However, the role of SM22α in VSMC apoptosis is controversial. Here, we identified that SM22α loss contributed to apoptosis of VSMCs via activation of macrophages. Firstly, deficiency of SM22α enhanced the interaction of VSMCs with macrophages. Macrophages were retained and activated by Sm22α -/- VSMCs via upregulating VCAM-1 expression. The ratio of apoptosis was increased by 1.62-fold in VSMCs treated with the conditional media (CM) from activated RAW264.7 cells, compared to that of the control CM (P < 0.01), and apoptosis of Sm22α -/- VSMCs was higher than that of WT VSMCs (P < 0.001). Next, circRasGEF1B from activated macrophages was delivered into VSMCs promoting ZFP36 expression via stabilization of ZFP36 mRNA. Importantly, circRasGEF1B, as a scaffold, guided ZFP36 to preferentially bind to and decay Bcl-2 mRNA in a sequence-specific manner and triggered apoptosis of VSMCs, especially in Sm22α -/- VSMCs. These findings reveal a novel mechanism by which the circRasGEF1B-ZFP36 axis mediates macrophage-induced VSMC apoptosis via decay of Bcl-2 mRNA, whereas Sm22α -/- VSMCs have a higher sensitivity to apoptosis.

[Roles of smooth muscle 22α in vascular homeostasis and vascular remodeling].

The research on the molecular mechanism of vascular injury has been a hot topic in recent years since the mechanism can be targeted for the treatment of vascular injury diseases. A large number of studies have found that vascular injury, repair and pathological remodeling are closely related to phenotype switching, abnormal proliferation and migration, and apoptosis of vascular smooth muscle cells (VSMCs). Smooth muscle 22α (SM22α) is a shape change and transformation sensitive F-actin-binding protein. SM22α decorates the contractile filament bundles within cultured VSMCs exhibiting differentiated phenotypes. In addition, SM22α is involved in regulation of cell signaling pathways related to vascular homeostasis and vascular remodeling. Here, we reviewed the recent research progress of SM22α in vascular homeostasis and remodeling.

circ-Sirt1 Decelerates Senescence by Inhibiting p53 Activation in Vascular Smooth Muscle Cells, Ameliorating Neointima Formation.

Vascular smooth muscle cell (VSMC) senescence is a major driver of neointimal formation. We have demonstrated that circ-Sirt1 derived from the SIRT1 gene suppressed VSMC inflammation and neointimal formation. However, the effect of circ-Sirt1 inhibiting inflammation on VSMC senescence during neointimal hyperplasia remains to be elucidated. Here, we showed that circ-Sirt1 was highly expressed in young and healthy arteries, which was decreased in aged arteries and neointima of humans and mice. Overexpression of circ-Sirt1 delayed Ang II-induced VSMC senescence in vitro and ameliorated neointimal hyperplasia in vivo. Mechanically, circ-Sirt1 inhibited p53 activity at the levels of transcription and post-translation modulation. In detail, circ-Sirt1, on the one hand, interacted with and held p53 to block its nuclear translocation, and on the other hand, promoted SIRT1-mediated p53 deacetylation and inactivation. In conclusion, our data suggest that circ-Sirt1 is a novel p53 repressor in response senescence-inducing stimuli, and targeting circ-Sirt1 may be a promising approach to ameliorating aging-related vascular disease.

Smooth muscle SIRT1 reprograms endothelial cells to suppress angiogenesis after ischemia.

Objective: Vascular smooth muscle cells (VSMCs) undergo the phenotypic changes from contractile to synthetic state during vascular remodeling after ischemia. SIRT1 protects against stress-induced vascular remodeling via maintaining VSMC differentiated phenotype. However, the effect of smooth muscle SIRT1 on the functions of endothelial cells (ECs) has not been well clarified. Here, we explored the role of smooth muscle SIRT1 in endothelial angiogenesis after ischemia and the underlying mechanisms. Methods: We performed a femoral artery ligation model using VSMC specific human SIRT1 transgenic (SIRT1-Tg) and knockout (KO) mice. Angiogenesis was assessed in in vivo by quantification of the total number of capillaries, wound healing and matrigel plug assays, and in vitro ECs by tube formation, proliferation and migration assays. The interaction of HIF1α with circRNA was examined by using RNA immunoprecipitation, RNA pull-down and in situ hybridization assays. Results: The blood flow recovery was significantly attenuated in SIRT1-Tg mice, and markedly improved in SIRT1-Tg mice treated with SIRT1 inhibitor EX527 and in SIRT1-KO mice. The density of capillaries significantly decreased in the ischemic gastrocnemius of SIRT1-Tg mice compared with SIRT1-KO and WT mice, with reduced expression of VEGFA, which resulted in decreased number of arterioles. We identified that the phenotypic switching of SIRT1-Tg VSMCs was attenuated in response to hypoxia, with high levels of contractile proteins and reduced expression of the synthetic markers and NG2, compared with SIRT1-KO and WT VSMCs. Mechanistically, SIRT1-Tg VSMCs inhibited endothelial angiogenic activity induced by hypoxia via the exosome cZFP609. The cZFP609 was delivered into ECs, and detained HIF1α in the cytoplasm via its interaction with HIF1α, thereby inhibiting VEGFA expression and endothelial angiogenic functions. Meantime, the high cZFP609 expression was observed in the plasma of the patients with atherosclerotic or diabetic lower extremity peripheral artery disease, associated with reduced ankle-brachial index. Knockdown of cZFP609 improved blood flow recovery after hindlimb ischemia in SIRT1-Tg mice. Conclusions: Our findings demonstrate that SIRT1 may impair the plasticity of VSMCs. cZFP609 mediates VSMCs to reprogram endothelial functions, and serves as a valuable indicator to assess the prognosis and clinical outcomes of ischemic diseases.

circ-Sirt1 controls NF-κB activation via sequence-specific interaction and enhancement of SIRT1 expression by binding to miR-132/212 in vascular smooth muscle cells.

NF-κB-mediated inflammatory phenotypic switching of vascular smooth muscle cells (VSMCs) plays a central role in atherosclerosis and neointimal formation. However, little is known about the roles of circRNAs in the regulation of NF-κB signaling. Here, we identify the involvement of circ-Sirt1 that was one of transcripts of SIRT1 host gene in VSMC inflammatory response and neointimal hyperplasia. First, in the cytoplasm, circ-Sirt1 directly interacts with and sequesters NF-κB p65 from nuclear translocation induced by TNF-α in a sequence-dependent manner. The inhibitory complex of circ-Sirt1-NF-κB p65 is not dependent on IκBα. Second, circ-Sirt1 binds to miR-132/212 that interferes with SIRT1 mRNA, and facilitates the expression of host gene SIRT1. Increased SIRT1 results in deacetylation and inactivation of the nuclear NF-κB p65. These findings illustrate that circ-Sirt1 is a novel non-coding RNA regulator of VSMC phenotype.

Insulin-independent GLUT4 translocation in proliferative vascular smooth muscle cells involves SM22α.

The insulin-sensitive glucose transporter 4 (GLUT4) is a predominant facilitative glucose transporter in vascular smooth muscle cells (VSMCs) and is significantly upregulated in rabbit neointima. This study investigated the role of GLUT4 in VSMC proliferation, the cellular mechanism underlying PDGF-BB-stimulated GLUT4 translocation, and effects of SM22α, an actin-binding protein, on this process. Chronic treatment of VSMCs with PDGF-BB significantly elevated GLUT4 expression and glucose uptake. PDGF-BB-induced VSMC proliferation was dependent on GLUT4-mediated glucose uptake. Meanwhile, the response of GLUT4 to insulin decreased in PDGF-BB-stimulated VSMCs. PDGF-BB-induced GLUT4 translocation partially rescued glucose utilization in insulin-resistant cells. Immunofluorescence and western blot analysis revealed that PDGF-BB induced GLUT4 translocation in an actin dynamics-dependent manner. SM22α disruption facilitated GLUT4 translocation and glucose uptake by promoting actin dynamics and cortical actin polymerization. Similar results were observed in VSMCs of SM22α -/- mice. The in vivo experiments showed that the glucose level in the neointima induced by ligation was significantly increased in SM22α -/- mice, accompanied by increased neointimal thickness, compared with those in wild-type mice. These findings suggest that GLUT4-mediated glucose uptake is involved in VSMC proliferation, and provide a novel link between SM22α and glucose utilization in PDGF-BB-triggered proliferation. KEY MESSAGES: • GLUT4-mediated glucose uptake is required for the VSMC proliferation. • PDGF-BB-induced GLUT4 translocation partially rescues glucose uptake in insulin resistance. • SM22α disruption enhances PDGF-BB-induced GLUT4 translocation. • Glucose level in injured vascular tissue is positively correlated with neointimal hyperplasia.

[FAK-related non-kinase plasmid transfection inhibited hepatic stellate cells proliferation].

AIM: To observe the effect of FAK-related non-Kinase (FRNK) plasmid on hepatic stellate cell (HSC) proliferation stimulated by fibronectin (FN). METHODS: FRNK plasmid was transfected into HSC with transient liposomal transfection. The proteins of FRNK, FAK and p-FAK(Tyr397) were assayed by Western blotting analysis. The proliferation of HSC was evaluated by improved MTT assay, and cell cycle pattern was determined by flow cytometry (FCM). RESULTS: (1) The expression of FRNK protein increased after FRNK transfected HSC, and it was at 48 h that the expression of FRNK protein was the highest (P < 0.01). The protein level of FAK was no significant difference between before FRNK plasmid transfection and after transfection (P > 0.05). The expression of p-FAK(Tyr397) protein was down-regulated after FRNK had been transfected in HSC, (P < 0.01). (2) The HSC proliferation inhibition rates at 12 h, 24 h and 48 h after FRNK transfection were 20.07%, 26.16%, 29.77%, respectively (P < 0.01). (3) Compared with the non-FRNK plasmid group, the FRNK-transfected HSCs almost arrested in G0/G1 phase (71.4 +/- 2.81 vs 48.9 +/- 1.66, P < 0.01). CONCLUSION: After FRNK were transfected successfully in HSCs using lipofectamine, the phosphorylation of FAK was inhibited. The HSC proliferation was restrained in a time-dependent manner and the HSC was arrested in G0/G1 phase.

[Clinical features and prognosis of decompensated hepatitis C virus related cirrhosis].

OBJECTIVE: To study the clinical features and prognosis of hepatitis C virus (HCV)-related cirrhosis after the first occurrence of complications. METHODS: The clinical data of 89 decompensated HCV-related cirrhosis patients were analyzed. Univariate and multivariate analyses of the factors influencing the clinical decompensation were conducted. RESULTS: Ascites was the most frequent first decompensation (44.9%), followed by upper gastrointestinal bleeding (23.6%), and self-originated peritonitis (20.2%), and hepatic encephalopathy (11.2%). During the follow-up of 62 months (60-66 months) ascites was the most frequent first decompensation (47. 2%), followed by self-originated peritonitis (18.0%), upper gastrointestinal bleeding (15.7%), and hepatic encephalopathy (7.9%). The 5-year survival rates after of the patients with hepatic encephalopathy, ascites, upper gastrointestinal bleeding and self-originated peritonitis as the first decompensated complications were 64.5%, 85.0%, 75.0%, and 83.3% respectively. Multivariate regression analysis showed that esophageal and gastro varices and bilirubin were independently correlated with survival. CONCLUSION: Hepatitis C is a slowly progressing disease. Decompensation occurring in hepatitis C is significantly correlated with survival.

[Clinical characteristics of patients with hemorrhagic fever with renal syndrome].

OBJECTIVE: Patients with typical clinical manifestations of Hemorrhagic fever with renal syndrome (HFRS) are becoming fewer. We conducted analysis on clinical features of HFRS in order to reduce the mistakes in diagnosis. METHODS: 64 patients were diagnosed as HFRS during May, 2000 to June, 2006 in our hospital. All the patients' serological tests (HFRS-NP-specific IgM, IgG antibody) by ELISA method were positive. We collected their clinical manifestations and test results. SPSS 12.0 was used in our statistical analysis. RESULTS: Among the 64 patients, 71.6% of all the cases occurred from Feb. to June. Most of patients were admitted to the hospital with untypical manifestation. Only 30.6% patients appeared headache, lumbago, and pain of orbital cavity. 32.8% patients had obviously signs of injection and hemorrhage. However, there were 90.6% patients with headache and 84.4% patients with nausea or vomit. Hypotensive or oliguric phases were absent in 56.3% patients. There were only 31.3% patients with all five stages. Thrombocytopenia (79.7%) and heavy proteinuria (71.9%) were common. But 54.7% of patients shown normal or even decreased white blood cell count. Only 2/3 of patients had elevated serum creatinine (Cr). Liver involved was common showing as elevated aminotransferase. ALT level was not always parallel to Cr level. There was an opposite trend between them. CONCLUSION: We must recognized the untypical manifestations of HFRS. Further study focus on pathogenesis was useful for diagnosis and therapy.

[Study on anti-endotoxin of baicalin].

OBJECTIVE: To study the anti-endotoxin of different concentration baicalin. METHODS: 6.250 microg/mL, 3.125 microLg/mL, 1.562 microg/mL and 0.781 microg/mL baicalin solutions were mixed with I EU/mL endotoxin, respectively. The mixtures were put into water of (37+/-1) degrees C for 15 min, 30 min and 60 min. The degrading effects were determined by using limulus amebocyte lysate test (LAL test). RESULTS: 1) The degrading effect of 6.250 microg/mL, 3.125 microg/mL and 1.562 microg/mL baicalin solution on I EU/mL endotoxin was degraded completely in 15 min, 30 min and 60 min, respectively. 2)The degrading effect of 3.125 microg/mL, 1.562 microg/mL and 0.781 microg/mL baicalin solution on 1 EU/mL endotoxin after these mixtures had been incubated for 15 min. Endotoxin values were (0.155 5 +/- 0.002 8) EU/mL, (0.212 1+/-0.004 9) EU/mL, (0.355 9+/-0.013 9) EU/mL, respectively. These differences among them were statistically significant (P<0.01). 3) The degrading effect of 1.562 microg/mL and 0.781 microg/mL baicalin solution on 1 EU/mL endotoxin after these mixtures had been incubated for 30 min. Endotoxin values were (0.1640+/-0.0025) EU/mL and (0.2094+/-0.004 4) EU/mL, respectively. These differences between them were statistically significant (P<0.01). CONCLUSION: The action of anti-endotoxin of baicalin is dose-dependent and time-dependent. The results show that baicalin has the stronger anti-endotoxin effect.