Erratum: Comparative study of nanostructured carriers of calcium phosphate and magnesium phosphate loaded with SRT1720 for the protection of H2O2-induced senescent endothelium.

[This corrects the article on p. 2068 in vol. 10, PMID: 30093944.].

Effect and Mechanism of LRP6 on Cardiac Myocyte Ferroptosis in Myocardial Infarction.

BACKGROUND: This study was aimed at exploring the biological function and molecular mechanism of ferroptosis of LRP6 modulation in cardiomyocytes of myocardial infarction (MI). METHOD: We established the ferroptosis model of MI in vivo and in vitro and constructed the modulation network of circRNA-miRNA-LRP6 by bioinformatics analysis; then, we focused on exploring the regulatory relationship of LRP6 and its upstream genes circRNA1615 and miR-152-3p in the RIP experiments and the double luciferase reporter gene assay. Also, we tested the LRP6-mediated autophagy-related ferroptosis in MI. RESULTS: Ferroptosis was found in cardiomyocytes of MI, and ferroptosis inhibitor Ferrostatin-1 (Fer-1) could improve the pathological process of MI. LRP6 was involved in the process of ferroptosis in cardiomyocytes, and LRP6 deletion regulated ferroptosis in cardiomyocytes through autophagy. Screening and identification of the upstream gene circRNA1615 would target LRP6. circRNA1615 inhibited ferroptosis in cardiomyocytes, and circRNA1615 could regulate the expression of LRP6 through sponge adsorption of miR-152-3p, prevent LRP6-mediated autophagy-related ferroptosis in cardiomyocytes, and finally control the pathological process of MI. CONCLUSIONS: circRNA1615 inhibits ferroptosis via modulation of autophagy by the miRNA152-3p/LRP6 molecular axis in cardiomyocytes of myocardial infarction.

Effects of salvianolate lyophilized injection combined with Xueshuantong injection in regulation of BBB function in a co-culture model of endothelial cells and pericytes.

The combined use of two or more different drugs can better promote nerve recovery and its prognosis for treatment of stroke. The salvianolate lyophilized injection (SLI) and Xueshuantong Injection (XST) are two standardized Chinese medicine injections which have been widely used in the treatment of cerebrovascular diseases. Salvianolic acid B (Sal B) and Notoginsenoside R1 (NR1) is respectively one of the active constituents of SLI and XST, which have certain effects on stroke. In this study, we established a co-culture of endothelial cells and pericytes for oxygen-glucose deprivation/reperfusion (OGD/R) injury model to study the effects of SLI and Sal B or XST and NR1 alone, or with their combinations (1S1X) in regulation of BBB function. The results showed that compared with the OGD/R group, treatment with SLI, XST and SalB and NR1 can significantly increase the TEER, reduce the permeability of Na-Flu, enhance the expression of tight junctions (TJs) between cells, and stabilize the basement membrane (BM) composition. In addition, the combination of 1S1X is superior to the XST or SLI alone in enhancing the TJs between cells and stabilizing the BM. And the active components SalB and NR1 can play a strong role in these two aspects, even with the whole effects. Furthermore, the study showed that XST, Sal B and NR1 increases in Ang-1and Tie2, while decrease in Ang-2 and VEGF protein expressions. Overall, these findings suggest that SLI combined with XST (1X1S) has protective effects on co-culture of endothelial cells and pericytes after OGD/R. Moreover, its protective effect might be associated with increase of TJs and BMs through activation of Ang/Tie-2 system signaling pathway.

Anti-inflammatory effects of rosuvastatin treatment on coronary artery ectasia patients of different age groups.

BACKGROUND: Coronary artery ectasia (CAE) is an angiographic finding of abnormal coronary dilatation. Inflammation plays a major role in all phases of atherosclerosis. We investigated the relationship between CAE and serum high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) levels to test our hypothesis that patient age is associated with the efficacy of anti-inflammatory therapy for CAE. METHODS: We conducted a prospective analysis of 217 patients with CAE treated at the Department of Cardiology, Shanghai East Hospital, Ji'an Campus and the Baoshan People's Hospital, from January 1, 2015 to July 30, 2019. Baseline data of patients, including sex; age; and history of hypertension, hyperlipidemia, and diabetes, were collected from patient medical records. Study participants were grouped by age as follows: CAE-A (n = 60, age ≤ 50 years), CAE-B (n = 83, 50 years 70). Additionally, there was a control (NC) group (n = 73) with normal coronary arteries. RESULTS: All patients received oral rosuvastatin therapy (10 mg, QN quaque nocte) when they were diagnosed with CAE and maintained good follow-up, with a loss rate of 0.0% at the end of the 6-month follow-up. The NC group received regular symptom-relieving treatments and rosuvastatin therapy. Of these four groups, the inflammatory markers, hs-CRP and IL-6, were significantly higher in patients with CAE than in the NCs (p < 0.05). Post-hoc tests showed that hs-CRP and Il-6 levels had significant differences between the CAE-A and CAE-C groups (P = 0.048, P = 0.025). Logistic regression analysis showed that hs-CRP (OR = 1.782, 95% CI: 1.124-2.014, P = 0.021) and IL-6 (OR = 1.584, 95% CI: 1.112-1.986, P = 0.030) were independent predictors of CAE. The inflammatory markers were higher in the CAE-A group than in the CAE-B group and higher in the CAE-B group than in the CAE-C group. Follow-up after 6 months of rosuvastatin therapy showed a significantly greater reduction in hs-CRP and IL-6 levels in the CAE-A group than in the CAE-B group, which again were greater in the CAE-B group than in the CAE-C group. CONCLUSIONS: Anti-inflammatory therapy using rosuvastatin was more effective in younger CAE patients, indicating the need for early statin therapy in CAE.

Xueshuantong for Injection (Lyophilized, ) Alleviates Streptozotocin-Induced Diabetic Retinopathy in Rats.

OBJECTIVE: To investigate the ameliorate effect and underlying mechanism of Xueshuantong for Injection (Lyophilized, , XST) in streptozocin (STZ)-induced diabetic retinopathy (DR) rats. METHODS: Diabetes mellitus (DM) model was induced by intraperitoneal (i.p.) injection of STZ (60 mg/kg) in Sprague-Dawley rats. Diabetic rats were randomized into 3 groups (n=10) according to a random number table, including DM, XST50 and XST100 groups. XST treatment groups were daily i.p. injected with 50 or 100 mg/kg XST for 60 days, respectively. The control and DM groups were given i.p. injection with saline. Blood glucose level and body weight were recorded every week. Histological changes in the retina tissues were observed with hematoxylin-eosin staining. Apoptosis and inflammation related factors, including cleaved caspase-3, glial fifibrillary acidic protein (GFAP), tumor necrosis factor-α (TNF-α) and intercellular cell adhesion molecule-1 (ICAM-1) were detected by Western blot or real-time polymerase chain reaction. Then, the levels of advanced glycation end product (AGE) and its receptor (RAGE) were investigated. Tight junctions proteins (Zonula occludens-1 (ZO-1), Occludin and Claudin-5) of blood-retinal barrier were detected by Western blot. The levels of retinal fifibrosis, transforming growth factor-ß1 (TGF-ß1)-Smad2/3 signaling pathway were evaluated at last. RESULTS: There was no signifificant difference in the body weight and blood glucose level between XST and DM groups (P>0.05). Compared with the DM group, XST treatment signifificantly increased the retinal thickness of rats (P<0.05 or P<0.01), and suppressed cleaved caspase-3 expression (P<0.01). XST increased the protein expressions of ZO-1, Occludin and Claudin-5 and decreased the mRNA expressions of matrix metalloproteinase 2 (MMP-2) and MMP-9 (P<0.05 or P<0.01). Moreover, XST signifificantly reduced the productions of AGE and RAGE proteins in the retina of rats (P<0.05 or P<0.01), suppressed the over-expression of TNF-α, and decreased the elevated level of ICAM-1 in retina of rats (P<0.05 or P<0.01). XST signifificantly reduced the levels of α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF), TGF-ß1 and phosphorylation of Smad2/3 protein in rats (P<0.05 or P<0.01). CONCLUSIONS: XST had protective effects on DR with possible mechanisms of inhibiting the inflammation and apoptosis, up-regulating the expression of tight junction proteins, suppressing the productions of AGE and RAGE proteins, and blocking the TGF-ß/Smad2/3 signaling pathway. XST treatment might play a role for the future therapeutic strategy against DR.

Atypical presentation of SARS-CoV-2 infection: A case report.

BACKGROUND: The first case of pneumonia subsequently attributed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurred in Wuhan, Hubei Province on December 8, 2019. The symptoms included fever, coughing, and breathing difficulties. A few patients with this infection may only have atypical symptoms, which could lead to a misdiagnosis and subsequently further facilitate the spread of the virus. CASE SUMMARY: A 74-year-old female patient complained of severe diarrhea. She did not have fever, coughing, or breathing difficulties. A physical examination revealed no obvious positive signs. The patient had been hypertensive for more than 10 years. Her blood pressure was well controlled. On January 9, 2020, the patient's son visited a colleague who was later confirmed positive for SARS-CoV-2 and his first close contact with our patient was on January 17. The patient was first diagnosed with gastrointestinal dysfunction. However, considering her indirect contact with a SARS-CoV-2-infected individual, we suggested that an atypical pneumonia virus infection should be ruled out. A computed tomography scan was performed on January 26, and showed ground-glass nodules scattered along the two lungs, suggestive of viral pneumonia. Given the clinical characteristics, epidemiological history, and examination, the patient was diagnosed with coronavirus disease-2019 (COVID-19). CONCLUSION: Our patient had atypical symptoms of COVID-19. Careful acquisition of an epidemiological history is necessary to make a correct diagnosis and strategize a treatment plan.

Atorvastatin plus therapeutic ultrasound improve postnatal neovascularization in response to hindlimb ischemia via the PI3K-Akt pathway.

Statins and therapeutic ultrasound (TUS) have been shown to ameliorate angiogenesis on ischemic hindlimb animals and promote human umbilical vein endothelial cells (HUVECs) tube formation and proliferation. Here, we evaluate the therapeutic effect of TUS in combination with atorvastatin (Ator) therapy on angiogenesis in hindlimb ischemia and HUVECs. After subjecting excision of the left femoral artery, all mice were randomly distributed to one of four groups: Control; Ator treated mice (Ator); TUS treated mice (TUS); and Ator plus TUS treated mice (Ator+TUS). At day 14 post-surgery, the Ator plus TUS treatment cohort had the greatest blood perfusion, accompanied by elevated capillary density. In vitro, Ator plus TUS augmented tube formation, migration and proliferative capacities of HUVECs. Additionally, the united administration upregulated expression of angiogenic factors phosphorylated Akt (p-Akt), phosphorylated endothelial nitric oxide synthase (p-eNOS), as well as vascular endothelial growth factor (VEGF), both in vivo and in vitro. These benefits could be blocked by either phosphoinositide 3-kinase (PI3K) or eNOS inhibitor. Our data indicated that the united administration could significantly enhance ischemia-mediated angiogenesis and exert a protective effect against ischemic/hypoxia induced damage among HUVECs through up-regulating VEGF expression and activating the PI3K-Akt-eNOS pathway.

Shuxuetong injection protects cerebral microvascular endothelial cells against oxygen-glucose deprivation reperfusion.

Shuxuetong injection composed of leech (Hirudo nipponica Whitman) and earthworm (Pheretima aspergillum) has been used for the clinical treatment of acute stroke for many years in China. However, the precise neuroprotective mechanism of Shuxuetong injection remains poorly understood. Here, cerebral microvascular endothelial cells (bEnd.3) were incubated in glucose-free Dulbecco's modified Eagle's medium containing 95% N2/5% CO2 for 6 hours, followed by high-glucose medium containing 95% O2 and 5% CO2 for 18 hours to establish an oxygen-glucose deprivation/reperfusion model. This in vitro cell model was administered Shuxuetong injection at 1/32, 1/64, and 1/128 concentrations (diluted 32-, 64-, and 128-times). Cell Counting Kit-8 assay was used to evaluate cell viability. A fluorescence method was used to measure lactate dehydrogenase, and a fluorescence microplate reader used to detect intracellular reactive oxygen species. A fluorescent probe was also used to measure mitochondrial superoxide production. A cell resistance meter was used to measure transepithelial resistance and examine integrity of monolayer cells. The fluorescein isothiocyanate-dextran test was performed to examine blood-brain barrier permeability. Real-time reverse transcription polymerase chain reaction was performed to analyze mRNA expression levels of tumor necrosis factor alpha, interleukin-1ß, interleukin-6, and inducible nitric oxide synthase. Western blot assay was performed to analyze expression of caspase-3, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, occludin, vascular endothelial growth factor, cleaved caspase-3, B-cell lymphoma 2, phosphorylated extracellular signal-regulated protein kinase, extracellular signal-regulated protein kinase, nuclear factor-κB p65, I kappa B alpha, phosphorylated I kappa B alpha, I kappa B kinase, phosphorylated I kappa B kinase, claudin-5, and zonula occludens-1. Our results show that Shuxuetong injection increases bEnd.3 cell viability and B-cell lymphoma 2 expression, reduces cleaved caspase-3 expression, inhibits production of reactive oxygen species and mitochondrial superoxide, suppresses expression of tumor necrosis factor alpha, interleukin-1ß, interleukin-6, inducible nitric oxide synthase mRNA, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, markedly increases transepithelial resistance, decreases blood-brain barrier permeability, upregulates claudin-5, occludin, and zonula occludens-1 expression, reduces nuclear factor-κB p65 and vascular endothelial growth factor expression, and reduces I kappa B alpha, extracellular signal-regulated protein kinase 1/2, and I kappa B kinase phosphorylation levels. Overall, these findings suggest that Shuxuetong injection has protective effects on brain microvascular endothelial cells after oxygen-glucose deprivation/reperfusion. Moreover, its protective effect is associated with reduction of mitochondrial superoxide production, inhibition of the inflammatory response, and inhibition of vascular endothelial growth factor, extracellular signal-regulated protein kinase 1/2, and the nuclear factor-κB p65 signaling pathway.

Comparative study of nanostructured carriers of calcium phosphate and magnesium phosphate loaded with SRT1720 for the protection of H2O2-induced senescent endothelium.

Nanostructured calcium phosphate (CaP) and magnesium phosphate (MgP) are promising for the application as the nanocarriers in drug delivery. However, the difference between CaP and MgP nanocarriers in drug delivery is rarely investigated. In this work, we comparatively investigated nanostructured CaP, MgP and calcium magnesium phosphate (CMP) for the delivery of SRT1720, which is a silent information regulator (SIRT1) specific activator with pro-angiogenic and anti-aging properties in response to hydrogen peroxide (H2O2)-induced endothelial senescence. The protection of SRT1720-loaded CaP nanospheres, MgP nanosheets and CMP microspheres on the H2O2-induced senescent endothelium was examined by using human umbilical vein endothelial cells (HUVECs), demonstrating the improved cell viability, anti-aging, tube formation and migration. In addition, the SRT1720-loaded CaP nanospheres, MgP nanosheets and CMP microspheres can rescue the impaired angiogenic potential of HUVECs via activation of Akt/eNOS/VEGF pathway. The SRT1720-loaded MgP nanosheets and CMP microspheres have a similar protective effect compared with the pure SRT1720, while the SRT1720-loaded CaP nanospheres decrease the protective capability of SRT1720. These results lead us to figure out both MgP nanosheets and CMP microspheres are suitable and effective delivery for SRT1720 and this system can be further applied in vivo treatment.

Erratum: Comparative study of nanostructured carriers of calcium phosphate and magnesium phosphate loaded with SRT1720 for the protection of H2O2-induced senescent endothelium.

[This corrects the article on p. 2068 in vol. 10, PMID: 30093944.].

Curcumin induces G2/M cell cycle arrest and apoptosis of head and neck squamous cell carcinoma in vitro and in vivo through ATM/Chk2/p53-dependent pathway.

Studies have demonstrated that curcumin (CUR) exerts its tumor suppressor function in a variety of human cancers including head and neck squamous cell carcinoma (HNSCC). However, the exact underlying molecular mechanisms remain obscure. Here, we aim to test whether CUR affects ATM/Chk2/p53 signaling pathway, leading to the induction of cell cycle arrest, inhibition of angiogenesis of HNSCC in vitro and in vivo. To this end, we conducted multiple methods such as MTT assay, Invasion assay, Flow cytometry, Western blotting, RT-PCR, and transfection to explore the functions and molecular insights of CUR in HNSCC. We observed that CUR significantly induced apoptosis and cell cycle arrest, inhibited angiogenesis in HNSCC. Mechanistically, we demonstrated that CUR markedly up-regulated ATM expression and subsequently down-regulated HIF-1α expression. Blockage of ATM production totally reversed CUR induced cell cycle arrest as well as anti-angiogenesis in HNSCC. Moreover, our results demonstrated that CUR exerts its antitumor activity through targeting ATM/Chk2/p53 signal pathway. In addition, the results of xenograft experiments in mice were highly consistent with in vitro studies. Collectively, our findings suggest that targeting ATM/Chk2/p53 signal pathway by CUR could be a promising therapeutic approach for HNSCC prevention and therapy.

Therapeutic ultrasound protects HUVECs from ischemia/hypoxia-induced apoptosis via the PI3K-Akt pathway.

Background: Previous studies have demonstrated that therapeutic ultrasound (TUS) ameliorates angiogenesis on ischemic hind limb animals and also promotes human umbilical vein endothelial cells (HUVECs) tube formation. Apoptosis plays a key role in post-ischemic angiogenesis pathogenesis. However, the mechanisms underlying the anti-apoptotic effects of TUS are not clear. Therefore we put forward the hypothesis that TUS might promote angiogenesis during ischemia/hypoxia (I/H) by decreasing apoptosis. Methods: We investigated the cytoprotective role of TUS and the underlying mechanisms in I/H-induced HUVEC apoptosis. HUVECs were treated under hypoxic serum-starved conditions for 36 h and then treated with or without TUS (9 minutes, 1 MHz, 0.3 W/cm2). The cell viability was examined by the CCK-8 assay, apoptosis cell rate was determined by TUNEL staining and flow cytometry assay. In addition, the mitochondrial-dependent apoptosis pathway was evaluated by the protein activity of Bax, Bcl-2 and Caspase-3. Results: 1) apoptosis could be induced by I/H in HUVECs. 2) TUS attenuates HUVECs cell apoptosis induced by I/H. 3) TUS inhibits the protein expression of apoptosis modulators and effectors that regulate the mitochondrial pathway of apoptosis in HUVECs. 4) TUS increases the phosphorylation of Akt, which demonstrates the activation of the phosphoinositide 3-kinase (PI3K)- serine/threonine kinase (Akt) signal pathway. Conclusions: The present study indicates that exposure to TUS exerts a protective effect against I/H-induced apoptosis among HUVECs and that this process is mediated through the mitochondrial-dependent intrinsic apoptotic pathway. We also confirm that the PI3K-Akt signal cascade may be taken part in the TUS effects on apoptosis.

Inhibitory effects of Dioscin on atherosclerosis and foam cell formation in hyperlipidemia rats.

Macrophage-derived foam cells are well known for their key role in development of atherosclerosis (AS). The present study aimed to examine whether dioscin exerts anti-atherosclerotic activity and inhibits foam cell formation. A high-fat induced AS model and ox-LDL treated macrophages were established and received treatment of dioscin. Anti-atherosclerotic activity in vivo was assessed by atherosclerotic lesions size and aortic lipid contents. Macrophage formed foam cells were positively identified by oil red o staining. Moreover, the expression of LOX-1 and NF-κB in aorta tissue and macrophages was examined by western blotting assay. Our results showed that dioscin not only reduced the levels of plasma lipid, TNF-a, IL-1ß and IL-6, but also inhibited atherosclerotic development in AS rats, as evidenced by decreased atherosclerotic lesions size and aortic lipid level. In vitro study revealed dioscin directly reduced foam cell formation, decreased intracellular cholesterol accumulation and lowered TNF-a, IL-1ß and IL-6 secretion in ox-LDL treated macrophages. Interestingly, further work found dioscin significantly reduced expression of LOX-1 and NF-κB in the aortic tissue and ox-LDL treated macrophages. In summary, our study was the first to confirm anti-atherosclerotic activity of dioscin in vivo and vitro. Moreover, the other important finding is dioscin mediated ox-LDL/LOX-1/NF-κB regulated contributions to the attenuate macrophage ox-LDL uptake and AS.

Therapeutic ultrasound reverses peripheral ischemia in type 2 diabetic mice through PI3K-Akt-eNOS pathway.

Therapeutic ultrasound (TUS) has been demonstrated to improve endothelial nitric oxide synthase (eNOS) activity, which played a crucial role in the regulation of angiogenesis. Diabetes Mellitus (DM) impairs eNOS activity. We tested the hypothesis that DM may retard unilateral hindlimb ischemia-induced angiogenesis by inhibiting eNOS in high-fat diet (HFD)/streptozocin (STZ) induced diabetic mice, and that TUS may reverse DM-related impairment of angiogenesis. C57BL/6 mice were allocated to four groups: (A) mice were fed standard diet (control); (B) mice were fed standard diet and treated with TUS (control+TUS); (C) type-2 DM mice were induced by HFD/STZ (diabetic); and (D) type-2 DM mice and treated with TUS (dabetic+TUS). All mice were surgically induced unilateral limb ischemia. The ischemic skeletal muscles in groups B and D were irradiated with extracorporeal TUS for 9 minutes/day (frequency of 1 MHz, intensity of 0.3 W/cm2) for 14 consecutive days. The result showed that TUS augmented the blood perfusion, increased capillary density accompanied by an upregulation of angiogenic factors and a downregulation of apoptotic proteins in group D relative to group C. In vitro, TUS inhibited the apoptosis, promoted tubule formation, proliferation and migration capacities, increased angiogenic factors expression and reduced apoptotic protein levels in human umbilical vein endothelial cells (HUVECs). Furthermore, TUS can robust reverse the inhibiting effect induced by high glucose (HG) on HUVECs, and these benefits could be blocked by phosphoinositide 3-kinase (PI3K) inhibitor (LY294002) or eNOS inhibitor (L-NAME). Together, TUS restored type-2 DM-mediated inhibition of ischemia-induced angiogenesis, partially via PI3K-Akt-eNOS signal pathway.

SRT1720, a SIRT1 specific activator, protected H2O2-induced senescent endothelium.

Silent information regulator 1 (SIRT1) plays a critical role in maintaining vascular homeostasis via modulating senescent-related signal pathway, however, the molecular mechanism remains modest clarified. The purpose of this study was to examine whether SIRT1 specific activator SRT1720 would exhibit pro-angiogenic and anti-aging properties in response to hydrogen peroxide (H2O2)-induced endothelial senescence, and determine the underlying mechanisms. We pre-treated senescent human umbilical vein endothelial cells (HUVECs) with SRT1720, senescence-associated beta-galactosidase activity, apoptosis, migration, tube formation, proliferation and angiogenic factors were quantitatively examined. The results revealed that pharmacologic activation of SIRT1 by SRT1720 rescued apoptotic HUVECs and upregulated angiogenic response through reinforcing the protein expressions of angiogenic and survival factors in vitro. Furthermore, we confirmed that the expressions of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and phosphoryl-Akt were augmented in SRT1720-treated senescent HUVECs. In conclusion, our data indicated that SRT1720 could protect against endothelial senescence and maintain cell function via Akt/eNOS/VEGF axis.

Rescue of hypertension-related impairment of angiogenesis by therapeutic ultrasound.

We examined the hypothesis that therapeutic ultrasound (TUS) treatment would rescue the hypertension-related inhibition of ischemia-induced angiogenesis. TUS protects against endothelial dysfunction, but it is little known that the effect of TUS treatment on angiogenesis inhibited by hypertension. 20-week-old male spontaneously hypertensive rats (SHRs) and Wistar-Kyoto rats (WKYs) were randomly allocated to 4 groups: SHR; TUS treated SHR (SHR-TUS); WKY and TUS treated WKY (WKY-TUS). After undergoing excision of the left femoral artery, the ischemic skeletal muscles were treated with extracorporeal TUS for 9 minutes of daily exposure (frequency of 1 MHz, intensity of 0.3 W/cm(2)) for 14 consecutive days. We found that TUS normalized the blood perfusion in SHR-TUS accompanied by elevated capillary density. Similar results were found in the protein expression of angiogenic factors. TUS treatment also enhanced peripheral capillary density in WKY rats and restored the capillary rarefaction in hypertension by elevating the protein levels of endothelial nitric oxide synthase (eNOS), hypoxic inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and phosphorylated Akt (p-Akt) in vivo. Our data demonstrated that TUS treatment ameliorated hypertension-related inhibition of ischemia-induced angiogenesis, at least in part, via an NO-dependent manner.

Angiogenesis effect of therapeutic ultrasound on HUVECs through activation of the PI3K-Akt-eNOS signal pathway.

Therapeutic angiogenic effects of low-intensity ultrasound have been reported in endothelial cells and animal models of hind limb ischemia. It has been shown that the proliferation, migration, and tube formation of endothelial cells play critical roles in angiogenesis. The purpose of this study was to determine the underlying mechanism of low-intensity continuous therapeutic ultrasound on angiogenesis in endothelial cells. In the present study, human umbilical vein endothelial cells (HUVECs) were simulated of low-intensity therapeutic ultrasound (TUS, 1 MHz, 0.3 W/cm(2), 9 minute per day) for 3 days, and we observed migration, tube formation, and expression of endothelial nitric oxide synthase (eNOS) and serine/threonine kinase (Akt) in HUVECs. Specific inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) were added to the culture medium and TUS-induced changes in the pathways that mediate angiogenesis were investigated. After exposure to TUS, HUVECs tube formation and migration were significantly promoted, which was blocked by the eNOS inhibitor Immunofluorescence assay and Western blotting analysis demonstrated that eNOS expression in the HUVECs was significantly increased after TUS exhibition. Proteins of phosphorylated eNOS and Akt were both up-regulated after TUS stimulation. However, the specific inhibitor of PI3K not only significantly decreased the expression of p-Akt, but also down-regulated the p-eNOS. This suggested that the PI3K/Akt signal pathway might participate in modulating the activity of eNOS. In short, TUS therapy promotes angiogenesis through activation of the PI3K-Akt-eNOS signal cascade in HUVECs.

Curcumin as therapeutics for the treatment of head and neck squamous cell carcinoma by activating SIRT1.

SIRT1 is one of seven mammalian homologs of Sir2 that catalyzes NAD(+)-dependent protein deacetylation. The aim of the present study is to explore the effect of SIRT1 small molecule activator on the anticancer activity and the underlying mechanism. We examined the anticancer activity of a novel oral agent, curcumin, which is the principal active ingredient of the traditional Chinese herb Curcuma Longa. Treatment of FaDu and Cal27 cells with curcumin inhibited growth and induced apoptosis. Mechanistic studies showed that anticancer activity of curcumin is associated with decrease in migration of HNSCC and associated angiogenesis through activating of intrinsic apoptotic pathway (caspase-9) and extrinsic apoptotic pathway (caspase-8). Our data demonstrating that anticancer activity of curcumin is linked to the activation of the ATM/CHK2 pathway and the inhibition of nuclear factor-κB. Finally, increasing SIRT1 through small molecule activator curcumin has shown beneficial effects in xenograft mouse model, indicating that SIRT1 may represent an attractive therapeutic target. Our studies provide the preclinical rationale for novel therapeutics targeting SIRT1 in HNSCC.

MiR-21/miR-375 ratio is an independent prognostic factor in patients with laryngeal squamous cell carcinoma.

We sought to identify microRNAs that exhibit altered expression in laryngeal squamous cell carcinoma (SCC) and to determine whether microRNA expression is predictive of disease. This study was divided into three steps: (1) The expression of six miRNAs, such as up-regulated miR-223, miR-142-3p, miR-21, miR-16, miR-23a and down-regulated miR-375, was evaluated using total RNA isolated from freshly-frozen primary tumors and non-cancerous laryngeal squamous epithelial tissues and analyzed using quantitative real-time polymerase chain reaction (qRT-PCR). (2) We also investigated the mRNA expression levels of processing elements (RNASEN, DGCR8, and DICER1) that participate in miRNA-biogenesis pathway. (3) We analyzed the relationships between the expression levels of these miRNAs and the clinicopathologic parameters of laryngeal SCC patients. In this study, we found that: (1) A marked difference in the microRNA expression pattern was observed between tumors and non-cancerous tissue. With regard to miRNA-processing elements, the expression level of RNASEN was higher in laryngeal SCC than in normal epithelium (P<0.01). (2) The miR-21/miR-375 expression ratio was highly sensitive and specific for disease prediction. Kaplan-Meier analysis revealed a significant association between high expression of miR-21/miR-375 in cancerous tissue and a worse prognosis (p=0.032). (3) Furthermore, the expression ratio of miR-21/mir-375 in patients with stage (III-IV) tumors was significantly higher than that in those with stage (I-II) tumors (p=0.006). These data suggest that the pattern of microRNA expression in primary laryngeal SCC tissues is exhibiting strong predictive potential.

Pulsed electromagnetic field improves postnatal neovascularization in response to hindlimb ischemia.

Pulsed electromagnetic fields (PEMF) have been shown to promote proliferation and regeneration in the damaged tissue. Here, we examined whether PEMF therapy improved postnatal neovascularization using murine model of hindlimb ischemia, and the underlying cellular/molecular mechanisms were further investigated. Hindlimb ischemia was induced by unilateral femoral artery resection using 6-8 week-old male C57BL6 mice. Then, mice were exposed to extracorporeal PEMF therapy (4 cycles, 8min/cycle, 30 ± 3 Hz, 5 mT) every day until day 14. Our data demonstrated that PEMF therapy significantly accelerated wound healing, decreased prevalence of gangrene and increased postnatal neovascularization. Moreover, the levels of vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS) and Akt phosphorylation in ischemic muscles were markedly enhanced following PEMF therapy. In vitro, PEMF inhibited the process of hypoxia-induced apoptosis and augmented tube formation, migration and proliferative capacities of human umbilical vein endothelial cells (HUVECs). Additionally, PEMF exposure increased VEGF secretion, as well as the eNOS and Akt phosphorylation, and these benefits could be blocked by either phosphoinositide 3-kinase (PI3K) or eNOS inhibitor. In conclusion, our data indicated that PEMF therapy enhanced ischemia-mediated angiogenesis, through up-regulating VEGF expression and activating the PI3K-Akt-eNOS pathway. Therefore, PEMF should be a valuable treatment for the patients with critical limb ischemia.