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Background Studies have shown that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) plays critical roles in the genesis and development of human cancers. Aim To investigate the clinical significance and role of IGF2BP1 in pancreatic cancer. Methods Expression levels of IGF2BP1 and microRNA-494 (miR-494) were mined based on Gene Expression Omnibus datasets and validated in both clinical samples and cell lines by quantitative real-time polymerase chain reaction and Western blot. The relationship between IGF2BP1 expression and clinicopathological factors of pancreatic cancer patients was analyzed. The effect and mechanism of IGF2BP1 on pancreatic cancer cell proliferation were investigated in vitro and in vivo. Analyses were performed to explore underlying mechanisms of IGF2BP1 upregulation in pancreatic cancer and assays were carried out to verify the post-transcriptional regulation of IGF2BP1 by miR-494. Results We found that IGF2BP1 was upregulated and associated with a poor prognosis in pancreatic cancer patients. We showed that downregulation of IGF2BP1 inhibited pancreatic cancer cell growth in vitro and in vivo via the AKT signaling pathway. Mechanistically, we showed that the frequent upregulation of IGF2BP1 was attributed to the downregulation of miR-494 expression in pancreatic cancer. Furthermore, we discovered that reexpression of miR-494 could partially abrogate the oncogenic role of IGF2BP1. Conclusion Our results revealed that upregulated IGF2BP1 promotes the proliferation of pancreatic cancer cells via the AKT signaling pathway and confirmed that the activation of IGF2BP1 is partly due to the silencing of miR-494.

Phthalates are commonly used in plastic products in daily life. The endocrine-disrupting effects of phthalates have been widely reported. Accumulating evidence from human cohorts and lab animals indicate exposure to phthalates might impair neurodevelopment. However, the direct causal relationship and mechanism between phthalates with neurodevelopment and neurotoxicity have not been firmly established. We found that phthalates (i.e. DBP, DINP, BBP) disrupted the expression of estrogen receptors (esr1, esr2a, esr2b), and impaired neurogenesis in the brain of zebrafish during embryonic development. Moreover, the abnormal expression of estrogen receptors, especially esr2a, was partly rescued in zebrafish which exposed to phthalates, with the estrogen receptor antagonist tamoxifen. Hence, impaired neurogenesis of zebrafish exposed to phthalates was partly reversed by tamoxifen treatment. Moreover, our results show that induced pluripotent stem cells (iPSC)-derived human neurons exposed to phthalates triggered double-strand DNA breaks in vitro. Overall, this study demonstrates that exposure to phthalates affects neurodevelopment in zebrafish embryos and induces neurotoxicity in human neurons partly through disrupting the expression of estrogen receptors.

Diabetic retinopathy (DR) is the common cause of diabetic vascular complications. The NOD-like receptor (NLR) family, pyrin domain containing 1 (NLRP1), also known as NALP1, inflammasome is the first member of the NLR family to be discovered, playing an important role in inflammatory response. However, its effect on DR development has not been reported. In the study, the wild type (WT) and NLRP1−/− mice were injected with streptozotocin (STZ) to induce DR. The results indicated that NLRP1−/− significantly increased bodyweight reduction and decreased blood glucose levels induced by STZ. WT/DR mice exhibited higher levels of NLRP1 in retinas. NLRP1−/− ameliorated retinal abnormalities in DR mice using H&E staining. In addition, attenuated avascular areas and neovascular tufts were also observed in NLRP1−/−/DR mice. The levels of pro-inflammatory cytokines in serum and retinas were highly induced in WT/DR mice, whereas being markedly reduced by NLRP1−/−. In addition, vascular endothelial growth factor (VEGF) and Iba1 expressions induced by STZ in serum or retinas were significantly down-regulated in NLRP1−/−/DR mice. Consistently, NLRP1−/− attenuated ASC and Caspase-1 expressions in retinas of DR mice. Compared to WT/DR group, NLRP1−/− markedly decreased retina p-nuclear factor-κB (NF-κB), interleukin-1β (IL-1β) and IL-18 levels. And similar results were confirmed in vitro that suppressing NLRP1/ASC inflammasome ameliorated inflammatory response in fructose-treated retinal ganglion cells. The results above indicated that the modulation of NLRP1 inflammasome might be a promising strategy for DR therapy.

Flavonoid dimer FD18 is a new class of dimeric P-gp modulator that can reverse cancer drug resistance. FD18 is a potent (EC50 = 148 nM for paclitaxel), safe (selective index = 574), and selective P-glycoprotein (P-gp) modulator. FD18 can modulate multidrug resistance toward paclitaxel, vinblastine, vincristine, doxorubicin, daunorubicin, and mitoxantrone in human breast cancer LCC6MDR in vitro. FD18 (1 μM) can revert chemosensitivity of LCC6MDR back to parental LCC6 level. FD18 was 11- to 46-fold more potent than verapamil. FD18 (1 μM) can increase accumulation of doxorubicin by 2.7-fold, daunorubicin (2.1-fold), and rhodamine 123 (5.2-fold) in LCC6MDR. FD18 inhibited P-gp-mediated doxorubicin efflux and has no effect on influx. FD18 at 1 μM did not affect the protein expression level of P-gp. Pharmacokinetics studies indicated that intraperitoneal administration of 45 mg/kg FD18 was enough to maintain a plasma level above EC50 (148 nM) for more than 600 min. Toxicity studies with FD18 (90 mg/kg, i.p. for 12 times in 22 days) with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) revealed no obvious toxicity or death in mice. In vivo efficacy studies indicated that FD18 (45 mg/kg, i.p. for 12 times in 22 days) together with paclitaxel (12 mg/kg, i.v. for 12 times in 22 days) resulted in a 46% reduction in LCC6MDR xenograft volume (n = 11; 648 ± 84 mm(3)) compared to paclitaxel control (n = 8; 1201 ± 118 mm(3)). There were no animal deaths or significant drop in body weight and vital organ wet weight. FD18 can increase paclitaxel accumulation in LCC6MDR xenograft by 1.8- to 2.2-fold. The present study suggests that FD18 represents a new class of safe and potent P-gp modulator in vivo.

Background The role of Kdr (VEGFR-2/Flk-1) in vascular formation has been well described, but the role of Flt1 (VEGFR-1) is not well studied and is generally considered as a decoy receptor for trapping VEGF. Methods The effects of VEGFR1/2 kinase inhibitor (VRI) and calycosin on Flt1 tyrosine kinase (TK) activity were evaluated by molecular docking, enzymatic inhibition assay, protein co-immunoprecipitation and siRNA gene knock-down analysis in HUVECs. Toxicities of the chemicals were examined using HUVECs viability. Their effects on angiogenesis and vessel formation were furthered studied in HUVECs in vitro and Tg ( fli-1 : EGFP ) zebrafish in vivo . The gene and protein expression of VEGF and VEGF receptors were investigated by quantitative RT-PCR and Western blot. Results VRI strongly inhibited physiological functions of both VEGF receptors and suppressed endothelial cell survival. This resulted in blood vessel loss in zebrafish embryos. Interestingly, calycosin co-treatment impeded VRI-induced blood vessel loss. Docking and kinase inhibition assay revealed that calycosin competed with VRI for the tyrosine kinase domain of Flt1 without affecting ATP binding. On the contrary, calycosin did not affect the interaction between VRI and Kdr-TK. Consistent with these results, calycosin counteracted the inhibition of Flt1-TK and PI3K phosphorylation induced by VRI in HUVECs. Further studies in vitro and in vivo showed that the minimizing effect of calycosin on VRI-mediated endothelial cytotoxicity was blocked by wortmannin (a PI3K inhibitor). The impeding effect of calycosin on VRI-induced blood vessel loss was absent in zebrafish embryos injected with Flt1 MO. Conclusions Flt1-tyrosine kinase (TK) activity contributed significantly in endothelial cells survival and vascular development during embryo angiogenesis in zebrafish by engaging PI3K/Akt pathway. General significance The roles of Flt1 activity in endothelial cell survival in physiological vascular formation may have been previously under-appreciated.

Crotamine is defensin-like cationic peptide from rattlesnake venom that possesses anticancer, antimicrobial, and antifungal properties. Despite these promising biological activities, toxicity is a major concern associated with the development of venom-derived peptides as therapeutic agents. In the present study, we used zebrafish as a system model to evaluate the toxicity of rhodamine B-conjugated (RhoB) crotamine derivative. The lethal toxic concentration of RhoB-crotamine was as low as 4 μM, which effectively kill zebrafish larvae in less than 10 min. With non-lethal concentrations (

Ethnopharmacological relevance Fritillariae Bulbus (Beimu in Chinese) is derived from the bulbus of many Fritillaria species (family Liliaceae), which has been used as an antitussive herb in traditional Chinese medicine for more than 2000 years. Due to the complexity of plant origins and significant variations in chemical profiles, the characterization of the profile of the major bioactive constituents and its association with pharmacological activity are important for the quality control of Beimu herbs from different origins. Aim of the study This study aims to investigate the distribution of major bioactive isosteroidal alkaloids in Beimu herbs of different origins and its correlation with the tracheobronchial relaxant activity. Methods Quantification of 7 main bioactive 5α-cevanine isosteroidal alkaloids, including ebeiedine, ebeiedinone, hupehenine, isoverticine, verticine, verticinone and imperialine, in 23 Fritillaria species was performed using gas chromatography. The relaxant effect of different extracts of 4 commonly used Beimu herbs, namely Zhe-Beimu (F. thunbergii Miq.), Chuan-Beimu (F. cirrhosa D. Don), Hubei-Beimu (F. hupehensis Hsiao et K. C. Hsia) and Yi-Beimu (F. pallidiflora Schrenk), was evaluated using rat isolated tracheal and bronchial preparations pre-contracted with carbachol, the well established in vitro antitussive model. Results Amongst 23 Fritillaria species detected, significant variations of the types and quantities of 7 major isosteroidal alkaloids were determined, which served as an important indicator for the classification of different Beimu herbs with distinct geographic distributions. Based on the type and quantity of these alkaloids, different origins of Beimu could be clearly clustered into several subgroups by principal component analysis. Furthermore, both crude alkaloid and water extracts of all 4 Beimu herbs showed a dose-dependent tracheobronchial relaxation with different potencies. The total content of alkaloids (weight adjusted based on the activity of individual alkaloids) in Beimu extracts significantly correlated with their tracheobronchial relaxation effects (r2 > 0.9, p Conclusions The results demonstrated that the differences in chemical profile of major bioactive isosteroidal alkaloids and pharmacological activity of Beimu could be incorporated into a simple and unified method for quality control and potential prediction of activity of Beimu herbs from different origins.

The onsets of left ventricular hypertrophy (LVH) and endothelial dysfunction (ED) in diabetics, especially in those with elevated homocysteine (Hcy), precede the development of cardiovascular (CV) events. Salvianic acid A (SAA) is a renowned Traditional Chinese Medicine (TCM) that has been applied in the treatment of cardiovascular disease for many decades. In this study, we aimed (1) to investigate the CV protective effects of SAA on ameliorating LVH and ED in db/db mice with elevated blood Hcy level and (2) to decipher whether the observed CV protective effects of SAA are associated with Hcy metabolism by modulating the methylation potential and redox status in the liver of the db/db mice with elevated blood Hcy level. Our results found that the administration of SAA could significantly slow down the build-up of left ventricular mass and ameliorate ED. Immunological assay analysis on the mouse liver tissue also indicated that SAA treatment on db/db mice with elevated Hcy was associated with reduced methylation potential but improved redox status. In conclusion, we revealed that SAA has the potential to protect against the hyperglycemia- and hyperhomocysteinemia-induced oxidative stress on diabetic mice via modulation in Hcy metabolism.

Ethnopharmacological relevance Semen Astragali Complanati (SAC), the dried ripe seed of Flatstem Milkvetch (Astragalus complanatus Bunge) (Leguminosae), is commonly used in traditional Chinese medicine (TCM) for treating muscle, liver, kidney, blood, skin and reproductive system diseases. Materials and methods Relevant information about SAC was gathered via “Google Scholar”, “ISI Web of Knowledge”, “PubMed”, “ScienceDirect”, “Medline Plus”, “ACS”, “CNKI” and “Wiley Online Library” and from books in local libraries. Results The major contents of SAC include fatty acids, amino acids, polysaccharides, flavonoids, triterpene glycosides and trace elements. Previous scientific studies have reported that SAC exhibits a number of therapeutic effects on chronic diseases such as cardiovascular diseases, diabetes mellitus and cancers. It has been found that flavonoids are the main bioactive component in SAC. However most of the previous studies have shown the effects brought by the total flavonoid fraction extracted from SAC only; further studies are warranted for the biological effects produced by individual components. There are only a few studies on the toxicity of SAC and the overall results show that its toxicity is quite low or even non-existent. Conclusions SAC is a valuable TCM herb with multiple pharmacological effects for treating some chronic diseases. More studies on SAC will help us to have a better understanding of its pharmacological mechanisms so as to provide more scientific evidence to explain its traditional uses, identify its therapeutic potential on other diseases and understand its possible harmful effects. Based on previous studies, it is easy to identify that antioxidant effect of SAC might play an important role on its pharmacological effects. Studying the effects of SAC on handling intracellular reactive oxygen species may be a potential direction to help understanding the molecular mechanisms of SAC on preventing and/or treating chronic diseases.

Ergothioneine is a thiourea derivative of histidine found in food, especially mushrooms. Experiments in cell-free systems and chemical assays identified this compound as a powerful antioxidant. Experiments were designed to test the ability of endothelial cells to take up ergothioneine and hence benefit from protection against oxidative stress. Reverse-transcription polymerase chain reaction and Western blotting demonstrated transcription and translation of an ergothioneine transporter in human brain microvascular endothelial cells (HBMECs). Uptake of [(3)H]ergothioneine occurred by the organic cation transporter novel type-1 (OCTN-1), was sodium-dependent, and was reduced when expression of OCTN-1 was silenced by small interfering RNA (siRNA). The effect of ergothioneine on the production of reactive oxygen species (ROS) in HBMECs was measured using dichlorodihydrofluorescein and lucigenin, and the effect on cell viability was studied using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. ROS production and cell death induced by pyrogallol, xanthine oxidase plus xanthine, and high glucose were suppressed by ergothioneine. The antioxidant and cytoprotective effects of ergothioneine were abolished when OCTN-1 was silenced using siRNA. The expression of NADPH oxidase 1 was decreased, and those of glutathione reductase, catalase, and superoxide dismutase enhanced by the compound. In isolated rat basilar arteries, ergothioneine attenuated the reduction in acetylcholine-induced relaxation caused by pyrogallol, xanthine oxidase plus xanthine, or incubation in high glucose. Chronic treatment with the compound improved the response to acetylcholine in arteries of rats with streptozotocin-induced diabetes. In summary, ergothioneine is taken up by endothelial cells via OCTN-1, where the compound then protects against oxidative stress, curtailing endothelial dysfunction.

Post-menopause, there is an increase in body weight, visceral adiposity, and risk of developing non-alcoholic fatty liver disease (NAFLD), which leads to various cardiovascular diseases (CVDs). Some natural products have proven useful for counteracting the detrimental effects of menopause. The rhizome of Ligusticum chuanxiong Hort. (LC) is a well-known medicinal herb widely used in Chinese communities for the treatment of CVDs. The hepatic and vascular protective effects of LC ethanolic extract under postmenopausal conditions were investigated on ovariectomized (OVX) rats supplemented with or without LC ethanolic extract (600 mg/kg body weight/day, p.o.) or 17β-estradiol (1 mg/kg body weight/day, p.o.) for 12 weeks. The current findings demonstrated that consumption of LC ethanolic extract could reduce the body weight gain, improve serum lipid profile (lowering low density lipoprotein cholesterol but raising high density lipoprotein cholesterol), combat NAFLD, and protect vascular endothelium in the OVX rats. The beneficial effects of LC may be associated with its antioxidant or vasorelaxant compounds, which enhance the levels of hepatic antioxidant enzymes and up-regulate endothelial nitric oxide synthase mRNA expression, respectively. Taken together, LC may be a promising natural supplement for postmenopausal women to prevent NAFLD and CVDs.

Cardiovascular disease (CVD) is a leading cause of morbidity and mortality in postmenopausal women. Danshen, the dried root of Salvia miltiorrhiza Bunge, has been used clinically in China to treat CVD and dyslipidemia in postmenopausal women, and its major active ingredients have been found to have an estrogenic effect. The aim of this study was to elucidate the underlying mechanism of danshen's protective effects on vascular function in an ovariectomized (OVX) hyperlipidemic rat model.Thirty-five 6-month-old female Sprague-Dawley rats were randomly divided into five groups: sham-operated rats with low-fat control diet + vehicle, sham-operated rats with high-fat diet (HFD) + vehicle, OVX rats with HFD + vehicle, OVX rats with HFD + 17β-estradiol (1 mg kg d, PO), and OVX rats with HFD + danshen aqueous extract (600 mg kg d, PO). After 12 weeks of treatment, gains in body weight and serum lipid profile levels in rats were measured and histological examination of livers was carried out. Vascular function was evaluated by measuring relaxation responses. Molecular mechanisms were also analyzed in isolated aorta.Treatment with danshen aqueous extract reduced body weight gain, improved serum lipid profiles, and prevented formation of fatty liver induced by HFD and OVX. In addition, danshen could increase endothelial-dependent vasorelaxation and displayed vasoprotection in OVX rats fed with HFD, primarily by stimulating nitric oxide (NO) production, up-regulating the mRNA expression of endothelial NO synthase, and down-regulating the mRNA expression of tumor necrosis factor α, intercellular cell adhesion molecule-1, and vascular cell adhesion molecule-1 in the isolated aortas.We conclude for the first time that danshen aqueous extract could protect OVX rats fed with HFD from endothelial dysfunction. Its effect may be related to its abilities to normalize serum lipid profiles and enhance NO availability in the vascular system. Our findings indicate that danshen aqueous extract could be a promising natural supplement for postmenopausal women for preventing CVD.

Some of the major components of Danshen (Salvia miltiorrhiza), a widely used Chinese herbal medicine rich in phenolic acids, are thermosensitive and may degrade to other phenolic acids during extractions with heating. The chemical profiles of Danshen water-extract may vary with different heat water extraction at different temperatures, affecting the composition and bioactivity of the extracts. In this study, six water-extracts of Danshen obtained from heat reflux water extraction and microwave-assisted extraction with water (MAE-W) at different temperatures were tested for their composition and pharmacological effects. Among these extracts, the third-round MAE-W (100°C) extract had the highest phenolic acids and tanshinones contents, with the strongest antioxidant activity in 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) assay and ferric reducing/antioxidant potential (FRAP) assay. This extract also showed the strongest inhibitory effects on 2,2'-azobis-2-amidinopropane (AAPH)-induced hemolysis in human red blood cells, hydrogen peroxide-induced apoptosis in rat heart H9c2 cells and the highest relaxation effects on rat basilar artery. The antioxidant effects of Danshen water-extracts linearly correlated to their relaxation effects (r=0.895-0.977). Through multiple linear regression analysis, danshensu was found to be the most significant marker in the antioxidant and vasodilation effects of Danshen water-extract, while tanshinone IIA as the marker on hydrogen peroxide-induced apoptosis in rat heart H9c2 cells. Danshensu is, therefore, a useful marker for the quality control of Danshen water-extracts in antioxidant and vasodilation, while tanshinone IIA for anti-apoptotic potential of different extracts.

An extract of Curcuma longa was tested in hypercholesterolemic rats to investigate its potential therapeutic effect on vascular conditions. Four experimental groups were used: normal diet (ND) control group, high cholesterol diet (HCD) group, and HCD subgroups supplemented with turmeric extract at 100 or 300 mg/kg of body weight (HCD100Tur and HCD300Tur groups, respectively). Turmeric extract was fed orally to animals, and dietary treatments lasted for 28 days. Hypercholesterolemia developed in the HCD, HCD100Tur, and HCD300Tur rats. Segments of the thoracic aorta were isolated, and an organ bath experiment was used to assess the vasorelaxation capability among all rats. Rats fed only HCD showed a marked decrease in acetylcholine-induced vasorelaxation compared with ND control rats. The HCD100Tur and HCD300Tur rats showed significant improvement in vasorelaxation compared with HCD rats. When vasorelaxation was induced by high concentrations of sodium nitroprusside, no differences in vasorelaxation were observed among the four groups of rats. A mechanistic study showed that HCD100Tur and HCD300Tur rats had significantly higher levels of the antioxidant enzymes superoxide dismutase and glutathione peroxidase than HCD rats. The transcript levels of heat shock protein 70 (hsp70), bcl2, bax-α, caspase (casp3), and glyceraldehyde 3-phosphate dehydrogenase in aortic tissues indicated that hypercholesterolemia significantly increased the expression of bax-α and casp3 but down-regulated bcl2 expression compared with the control group. Turmeric increased the expression of hsp70 and bcl2 but greatly reduced casp3 expression, indicating that turmeric improves vasorelaxation of the aorta in hypercholesterolemic rats by increasing antioxidant enzyme activities and likely suppressing apoptosis.

The anticancer effects of traditional Chinese medicine (TCM) have attracted the attention of the public vis-à-vis existing cancer therapies with various side effects. Lycium barbarum fruit, commonly known as Gou Qi Zi in China, is a potential anticancer agent/adjuvant. Its major active ingredients, L. barbarum polysaccharides (LBP), scopoletin and 2-O-β-D-glucopyranosyl-L-ascorbic acid (AA-2βG), are found to have apoptotic and antiproliferative effects on cancer cell lines. Moreover, LBP also contributes to body's immunomodulatory effects and enhances effects of other cancer therapies. It is not known whether there are any undesirable effects. Further studies on its pharmacological mechanisms and toxicology could facilitate a safe usage of this TCM herb.

Ischemic heart disease is a major cause of death in the world. Common therapies, such as primary coronary angioplasty and thrombolysis, are applied to restore blood supply to the heart, limit infarct size and reduce mortality. However, the restoration of blood supply would generate reactive oxygen species in damaged sites of the myocardium, intensifying the damage to the cardiac tissues. Radix Scutellariae baicalensis (Huangqin) is a well-known herb in traditional Chinese medicine with high antioxidant power. In this study, extract of the dry root of Scutellaria baicalensis Georgi (Sb) was confirmed to have a high content of flavonoids and phenolic compounds. The cardioprotective effects of the Sb extracts (3, 30 and 300 mg/kg) were evaluated in myocardial ischemia-reperfusion injuried rats. The results showed that animals that had received five-day pretreatment of the Sb extract (30 mg/kg) had a significant reduction in myocardial infarct size and a marked increase in the activity of catalase in the liver. The Sb extract could additionally enhance acetylcholine-induced vasorelaxation. It was proposed that the Sb extract exerted its cardioprotection by stimulating the catalase activity and improving vascular elasticity.

We evaluated the vasorelaxation effects of formononetin, an isoflavone/phytoestrogen found abundantly in Astragalus mongholicus Bunge, on rat isolated aorta and the underlying mechanisms involved. Cumulative administration of formononetin, genistein, daidzein and biochanin A relaxed phenylephrine-preconstricted aorta. Formononetin and biochanin A caused a similar magnitude of relaxation whereas daidzein was least potent. Mechanical removal of endothelium, L-NAME (100 microM) and methylene blue (10 microM) suppressed formononetin-induced relaxation. Formononetin increased endothelial nitric oxide (NO) synthase (eNOS), but not inducible NO synthase, activity with an up-regulation of eNOS mRNA and p-eNOS(Ser1177) protein expression. In endothelium-denuded preparations, formononetin-induced vasorelaxation was significantly reduced by glibenclamide (3 microM) and iberiotoxin (100 nM), and a combination of glibenclamide (3 microM) plus iberiotoxin (100 nM) abolished the relaxation. In contrast, formononetin-elicited endothelium-independent relaxation was not altered by ICI 182,780 (10 microM, an estrogen receptor (ER alpha/ER beta) antagonist) or mifepristone (10 microM, a progesterone receptor antagonist). In single aortic smooth muscle cells, formononetin caused opening of iberiotoxin-sensitive Ca(2+)-activated K(+) (BK(Ca)) channels and glibenclamide-sensitive adenosine triphosphate (ATP)-dependent K(+) (K(ATP)) channels. Thus, our results suggest that formononetin caused vascular relaxation via endothelium/NO-dependent mechanism and endothelium-independent mechanism which involves the activation of BK(Ca) and K(ATP) channels.

The effects of folic acid (5.7 and 71 μg/kg, 4 weeks) consumption on the β-adrenoceptors (β-ARs)–elicited lipolysis in vitro of the abdominal adipocytes of lean/control (+ m/+ db) and obese/diabetic (+ db/+ db) mice (female) were investigated. β-AR agonists (salbutamol, a β2-AR agonist; BRL 37344 and CGP 12177, β3-AR agonists; adrenaline, a β-AR agonist)–mediated lipolysis, β2-, and β3-ARs protein expression of the adipose tissues after folic acid consumption were evaluated. Our results demonstrate that a smaller magnitude of the basal (spontaneous) and the β-AR agonists–triggered lipolysis was observed in + db/+ db mice, and folic acid supplementation (71 μg/kg) resulted in an improvement of both the baseline and the β-ARs–mediated lipolysis. In controls, a lower β2-and β3-ARs protein expression of the adipose tissues was detected in + db/+ db mice, compared to + m/+ db mice. In both strains fed with folic acid (71 μg/kg), a reduction of β2-AR protein expression was observed compared to the respective controls. In + db/+ db mice, folic acid (5.7 and 71 μg/kg) consumption caused a dose-dependent increase of β3-AR protein expression compared to controls. We demonstrate that lipolysis elicited by β-AR (β2- and β3-ARs) agonists was blunted in + db/+ db mice. Folic acid consumption has significant modulatory effects on β-ARs protein expression and lipolysis.

Hypercholesterolemia is a major risk factor for the development and progression of cardiovascular diseases including atherosclerosis. A major ac tive ingredient, scutellarin, from the plant Erigeron breviscapus was investigated for its hypocholesterolemic and atheroscleroprotective effects (30 and 100 mg/kg/day, p. o.). The serum lipid profile (total cholesterol, triglycerides, high density lipoprotein cholesterol and low density lipoprotein cholesterol) was monitored and aortic functions in Sprague-Dawley rats fed with normal diet, atherogenic diet or atherogenic diet plus oral administration of either scutellarin or simvastatin (a positive control) were tested. It was found that scutellarin markedly attenuated the increased serum total cholesterol induced by atherogenic diet. It caused a significant reduction in the atherogenic index. In addition, scutellarin administration could significantly enhance acetylcholine-induced nitrate/nitrite production, increase the gene expression of endothelial nitric oxide synthase and improve acetylcholine-induced endothelium-dependent vasorelaxation in rat isolated aortas. These data revealed that scutellarin could reduce the atherogenic properties of dietary cholesterol in rats. However, whether scutellarin's atheroscleroprotective potential targets endothelial function directly or indirectly on its antioxidative activity remains to be determined.

Nanoparticles based on amorphous poly(3-hydroxybutyrate)–poly(ethylene glycol)–poly(3-hydroxybutyrate) (PHB-PEG-PHB) are potential drug delivery vehicles, and so their cytotoxicity and hemolysis assay were investigated in vitro using two kinds of animal cells. The PHB-PEG-PHB nanoparticles showed excellent biocompatibility and had no cytotoxicity on animal cells, even when the concentrations of the PHB-PEG-PHB nanoparticle dispersions were increased to 120 μg/mL. Moreover, no hemolysis was detected with the PHB-PEG-PHB nanoparticles, suggesting that the PHB-PEG-PHB nanoparticles were obviously much hemocompatible for drug delivery applications. In the presence of intracellular enzyme esterase, the biocompatible PHB-PEG-PHB nanoparticles might be hydrolyzed, and their biodegradable behavior was monitored by the fluorescence spectrum and the pH meter. The initial biodegradation rate of the PHB-PEG-PHB nanoparticles was closely related to the enzymatic amount and the PHB block length. Compared with that obtained from the fluorescence determination, the initial biodegradation rate from pH measurement was faster. The biodegraded products mainly consisted of 3HB monomer and dimer, which were the metabolites present in the body. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 87A: 290–298, 2008

In this study, we determined the in vitro effect of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) activation on the aortic relaxation, lipolysis and insulin-induced [(3)H]-glucose uptake of the abdominal (omental) adipocytes of the non-diabetic (+db/+m) and obese/diabetic (+db/+db) mice. The expression of PPAR-gamma (mRNA and protein) in aorta and adipose tissues was evaluated and compared. Cumulative application of ciglitazone, pioglitazone and troglitazone (PPAR-gamma agonists) caused a concentration-dependent aortic relaxation (sensitive to 2-chloro-5-nitro-N-phenylbenzamide (GW9662) (1 microM, a selective PPAR-gamma antagonist) and N(omega)-nitro-l-arginine methyl ester (l-NAME) (20 microM, a nitric oxide synthase inhibitor)) with a maximum relaxation of approximately 30% (3 microM) in +db/+m mice, whereas no relaxation was observed in +db/+db mice. All PPAR-gamma agonists examined did not alter the basal lipolysis of both species, but forskolin caused a concentration-dependent lipolysis, with a greater magnitude observed in +db/+m mice. Insulin (0.1 and 1 microM) caused an enhancement of [(3)H]-glucose uptake into adipocytes with a greater magnitude in +db/+m mice. In contrast, none of the PPAR-gamma agonists tested (0.1, 1 and 10 microM) altered the basal and the insulin (0.1 microM)-induced [(3)H]-glucose uptake into adipocytes of both species. In addition, there was no difference in PPAR-gamma expression (mRNA and protein) in the aorta and adipose tissues between the species. In conclusion, our results demonstrate that PPAR-gamma is present in the abdominal (omental) adipose tissue and thoracic aorta. An acute activation of PPAR-gamma produced a small ( approximately 30%) aortic relaxation (nitric oxide/endothelium-dependent) of +db/+m mice. However, all PPAR-gamma agonists examined have no acute effect on lipolysis and the insulin-induced glucose uptake into adipocytes of both +db/+m and +db/+db mice.

In this study, we evaluated the anabolic effect and the underlying cellular mechanisms involved of vitamin K2 (10 nM) and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) (10 nM), alone and in combination, on primary osteoblasts harvested from the iliac crests of C57BL/KsJ lean (+/+) and obese/diabetic (db/db) mice. A lower alkaline phosphatase (ALP) activity plus a reduced expression of bone anabolic markers and bone formation transcription factors (osteocalcin, Runx2, Dlx5, ATF4 and OSX) were consistently detected in osteoblasts of db/db mice compared to lean mice. A significantly higher calcium deposits formation in osteoblasts was observed in lean mice when compared to db/db mice. Co-administration of vitamin K2 (10 nM) and 1,25(OH)2D3 (10 nM) caused an enhancement of calcium deposits in osteoblasts in both strains of mice. Vitamins K2 and 1,25(OH)2D3 co-administration time-dependently (7, 14 and 21 days) increased the levels of bone anabolic markers and bone formation transcription factors, with a greater magnitude of increase observed in osteoblasts of db/db mice. Combined vitamins K2 plus 1,25(OH)2D3 treatment significantly enhanced migration and the re-appearance of surface microvilli and ruffles of osteoblasts of db/db mice. Thus, our results illustrate that vitamins K2 plus D3 combination could be a novel therapeutic strategy in treating diabetes-associated osteoporosis.

Formononetin is an isoflavone that has been shown to display estrogenic properties and induce angiogenesis activities. However, the interrelationship between the estrogenic properties and angiogenesis activities of formononetin are not well defined. In the present study, docking and enzymatic assay demonstrated that formononetin displayed direct binding to the ligand-binding domain (LBD) of estrogen receptor alpha (ERα) with an agonistic property. Results from Human Umbilical Vein Endothelial Cells (HUVEC) by using real-time migration xCELLigence system, immunofluorescence and western blotting provided strong evidences of formononetin induced endothelial cell migration and dramatic actin cytoskeleton spatial modification through ERα-enhanced-ROCK-II/MMP2/9 signaling pathways. In addition, results from co-immunoprecipitation suggested formononetin induced cell migration via recruiting of ERα/ROCK-II activated complex formation. More interestingly, in zebrafish embryo we observed that formononetin significantly promoted angiogenic sproutings in the subintestinal vessels (SIVs) that could be completely abolished by ROCK inhibitor. In this study, we elucidated the underlying mechanisms that formononetin produced proangiogenesis effects through an ERα-enhanced ROCK-II signaling pathways. Results from the present study also expand our knowledge about the enigmatic underlying mechanisms of phytoestrogenic compounds in the promotion of angiogenesis in relation to ERα and ROCK interaction in endothelial cells and their relationship with actin assembly and cell migration.

Ethnopharmacological relevance The fruit of Schisandra chinensis (Turcz.) Baill, has been traditionally used in management of liver diseases and ageing associated neurodegeneration. The bioactive compound from this medicinal plant would be valuable for its potential use in prevention and treatment of Parkinson׳s disease. Aim of the study The overall objective of the present study was to understand the neuroprotective effect of schisantherin A, a dibenzocyclooctadiene lignan from the fruit of S. chinensis (Turcz.) Baill, and to elucidate its underlying mechanism of action. Material and methods This study investigated the protective effect of schisantherin A against selective dopaminergic neurotoxin 6-hydroxydopamine (6-OHDA)-induced neural damage in human neuroblastoma SH-SY5Y cells and zebrafish models. Oxidative stress and related signaling pathways underlying the neuroprotective effect were determined by multiple biochemical assays and Western blot. Results Pretreatment with schisantherin A offered neuroprotection against 6-OHDA-induced SH-SY5Y cytotoxicity. Moreover, schisantherin A could prevent 6-OHDA-stimulated dopaminergic neuron loss in zebrafish. Our mechanistic study showed that schisantherin A can regulate intracellular ROS accumulation, and inhibit NO overproduction by down-regulating the over-expression of iNOS in 6-OHDA treated SH-SY5Y cells. Schisantherin A also protects against 6-OHDA-mediated activation of MAPKs, PI3K/Akt and GSK3β. Conclusion These findings demonstrate that schisantherin A may have potential therapeutic value for neurodegenerative diseases associated with abnormal oxidative stress such as Parkinson׳s disease.

Danshen (Radix Salviae miltiorrhizae) and ChuanXiong (Ligusticum wallichii) are two traditional herbal medicines commonly used in China for the treatment of cardiovascular diseases. The active components in Danshen and ChuanXiong are Danshensu (DSS, (R)-3, 4-dihydroxyphenyllactic acid) and tetramethylpyrazine (TMP), respectively. In the present study, a new compound named ADTM, which is a conjugation of DSS and TMP, was synthesized and its effect on the contractility of rat mesenteric arteries was examined. The relaxation effect of ADTM on rat mesenteric arteries was studied using myography. The effects of ADTM on Ca(2+) channels were measured by Ca(2+) imaging and patch-clamp techniques. The results showed that ADTM caused a concentration-dependent relaxation of rat mesenteric arteries. This relaxation effect was not affected by the removal of endothelium or inhibitors of nitric oxide synthase, cyclooxygenase, guanylyl cyclase and adenylyl cyclase. Potassium channel blockers including tetraethylammonium, iberiotoxin, apamin, 4-aminopyridine, BaCl2 and glibenclamide also failed to inhibit the relaxation response to ADTM. ADTM inhibited CaCl2-induced contractions and reduced the Ca(2+) influx in isolated mesenteric arterial muscle cells. Our results suggest that ADTM may be a novel relaxing agent. Its mechanism of action involves the direct blockade of voltage-gated Ca(2+) channels in vascular smooth muscle cells, resulting in a decrease in Ca(2+) influx into the cells.

The rhizome of Ligusticum chuanxiong Hort. (LC), also known as chuanxiong, is a very common herb widely used to treat cardiovascular and cerebrovascular diseases. It is also used as a major ingredient in soups for regular consumption to promote good health. To study the protective effect of LC ethanolic extract (LCEE, 600 mg per kg per day, p.o.) on the integrity of the vascular system, ovariectomized (OVX) rats were fed with a high-fat diet (HFD) plus LCEE for 12 weeks. The animal model was used to mimic the dyslipidemic condition seen in postmenopausal women. LCEE was found significantly to reduce the body weight gain, improve serum lipid profiles (by lowering total cholesterol and low density lipoprotein cholesterol but raising high density lipoprotein cholesterol) and protect vascular endothelium in the HFD-fed OVX rats. It is postulated that LCEE could exert its vascular protective effect through multiple targets by (1) improving serum lipid profiles to reduce the detrimental effects of cholesterol; (2) reducing the ROS level in the body via enhancing the hepatic anti-oxidative activity or antioxidant level to scavenge the reactive oxygen species generated in the postmenopausal hypercholesterolemic condition; (3) stimulating eNOS-derived nitric oxide production; (4) counteracting the up-regulation of inflammatory cytokine (TNF-α, VCAM-1 and ICAM-1) expressions so as to reduce endothelium damage.

Oxidative stress is considered an important factor that promotes cell death in response to a variety of pathophysiological conditions. This study investigated the antioxidant properties of allicin, the principle ingredient of garlic, on preventing oxidative stress-induced injury. The antioxidant capacities of allicin were measured by using 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H(2)O(2))-induced cell damage on H9c2 cardiomyoblasts. Allicin (0.3-10 μM) pre-incubation could concentration-dependently attenuate the intracellular reactive oxygen species (ROS) increase induced by H(2)O(2) on H9c2 cells. It could also protect H9c2 cells against H(2)O(2)-induced cell damage. However, the DPPH free radical scavenging activity of allicin was shown to be low. Therefore, it is believed that the protective effect of allicin on H9c2 cells could inhibit intracellular ROS production instead of scavenging extracellular H(2)O(2) or free radicals. For the observed protective effect on H9c2 cells, allicin might also be effective in reducing free radical-induced myocardial cell death in ischemic condition.

In ischemic disorders such as chronic wounds and myocardial ischemia, there is inadequate tissue perfusion due to vascular insufficiency. Besides, it has been observed that prolonged use of anti-angiogenic agents in cancer therapy produces cardiovascular toxicity caused by impaired vessel integrity and regeneration. In the present study, we used VEGFR tyrosine kinase inhibitor II (VRI) to chemically induce vascular insufficiency in zebrafish in vivo and human umbilical vein endothelial cells (HUVEC) in vitro to further study the mechanisms of vascular morphogenesis in these pathological conditions. We also explored the possibility of treating vascular insufficiency by enhancing vascular regeneration and repair with pharmacological intervention. We observed that pretreatment of VRI induced blood vessel loss in developing zebrafish by inhibiting angiogenesis and increasing endothelial cell apoptosis, accompanied by down-regulation of kdr, kdrl and flt-1 genes expression. The VRI-induced blood vessel loss in zebrafish could be restored by post-treatment of calycosin, a cardiovascular protective isoflavone. Similarly, VRI induced cytotoxicity and apoptosis in HUVEC which could be rescued by calycosin post-treatment. Further investigation of the underlying mechanisms showed that the PI3K/AKT/Bad cell survival pathway was a main contributor of the vascular regenerative effect of calycosin. These findings indicated that the cardiovascular toxicity in anti-angiogenic therapy was mainly caused by insufficient endothelial cell survival, suggesting its essential role in vascular integrity, repair and regeneration. In addition, we showed that VRI-induced blood vessel loss in zebrafish represented a simple and effective in vivo model for studying vascular insufficiency and evaluating cancer drug vascular toxicities.

The incidence of cardiovascular diseases (CVDs) is high in both developed and developing countries. It has a high global rate of mortality and causes heavy social burden. Drugs are available for managing or treating CVDs and its complications. Consumption of dietary supplements or functional foods for reducing the risk of CVDs has also gained wide recognition by the general public. Piceatannol, an analog and metabolite of resveratrol, is a natural stilbene commonly found in the skin of grapes and wine. Piceatannol is believed to be a potent compound with certain cardiovascular therapeutic effects, such as the prevention of hypercholesterolemia, arrhythmia, atherosclerosis, and angiogenesis. It also has vasorelaxation and antioxidant activities. A comprehensive review of piceatannol concludes that piceatannol has the potential to be developed into health products for the cardiovascular system to help modern society reduce the high CVD incidence. However, further investigations are warranted in order to increase the bioavailability and understand the biological mechanisms and safety of using piceatannol.

Apoptotic neuronal cell death plays an important role in Parkinson's disease (PD), a progressive neurodegenerative disorder. Luteolin, a flavonoid, has been shown to possess various pharmacological properties including strong antioxidant capacity.This study investigated the neuroprotective effect of luteolin against cytotoxicity induced by 6-hydroxy-dopamine (6-OHDA) (250 µM) in rat pheochromocytoma (PC12) cell line.The neuroprotective effect of luteolin against 6-OHDA-induced cytotoxicity in PC12 was evaluated by using cell viability test, nuclear staining and flow cytometry. In addition, the apoptotic role of luteolin was unveiled by monitoring mRNA expression of proapoptotic and anti-apoptotic genes.Pretreatment with luteolin (3.13, 6.25, 12.5, 25 or 50 µM) could markedly attenuate 6-OHDA-induced PC12 cell viability loss in a concentration-dependent manner. Cell morphologic analysis and nuclear staining assays showed that luteolin (3.13, 12.5 or 50 µM) protected the cells from 6-OHDA-induced damage. As shown in the flow cytometry assay, the increased apoptotic rate induced by 6-OHDA could be significantly (p0.001) suppressed by luteolin (12.5 or 50 µM) pretreatment. The protection of luteolin (50 µM) against 6-OHDA-induced cell damage was shown to be through suppressing the over-expression of Bax gene (p0.01), inhibiting the reduction of Bcl-2 gene expression (p0.05) and markedly depressing the enhanced Bax/Bcl-2 ratio. Luteolin also downregulated the gene expression level of p53.Luteolin has protective effects against 6-OHDA-induced cell apoptosis and might be a potential nutritional supplement which could be used to prevent neurodegenerative diseases such as PD.

Cardiovascular disease (CVD) is a category of chronic noncommunicable diseases causing high global mortality and has been a heavy social burden in many countries. In the search of chemicals that arise from natural food source, allicin is one such ingredient from garlic that was discovered with the potential to provide beneficial effects to the cardiovascular system. From the pharmacokinetic studies, allicin is known to be hydrophobic and can be readily absorbed through the cell membrane without inducing any damage to the phospholipid bilayer and then rapidly metabolized to exert pharmacological effects that are important to the cardiovascular system. It was found to provide cardio-protective effects by inducing vasorelaxation and alleviating various pathological conditions of CVD, including cardiac hypertrophy, angiogenesis, platelet aggregation, hyperlipidemia and hyperglycemia. Allicin was also discovered to further protect the cardiovascular system by enhancing the antioxidant status by lowering the level of reactive oxygen species and stimulating the production of glutathione. Other pharmacological benefits such as anticancer and antimicrobial activities were also discussed. It is concluded that allicin can be potentially developed into a health product for the cardiovascular system.

Hypercholesterolemia is a major risk factor for the development of cardiovascular disease and nonalcoholic fatty liver disease. Natural compounds have been proved to be useful in lowering serum cholesterol to slow down the progression of cardiovascular disease and nonalcoholic fatty liver disease. In the present study, the hypocholesterolemic and hepatoprotective effects of the dietary consumption of chlorogenic acid were investigated by monitoring plasma lipid profile (total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein) in Sprague-Dawley rats fed with a normal diet, a high-cholesterol diet or a high-cholesterol diet supplemented with chlorogenic acid (1 or 10 mg/kg/day p.o.) for 28 days. Chlorogenic acid markedly altered the increased plasma total cholesterol and low-density lipoprotein but decreased high-density lipoprotein induced by a hypercholesterolemic diet with a dose-dependent improvement on both atherogenic index and cardiac risk factor. Lipid depositions in liver were attenuated significantly in hypercholesterolemic animals supplemented with chlorogenic acid. It is postulated that hypocholesterolemic effect is the primary beneficial effect given by chlorogenic acid, which leads to other secondary beneficial effects such as atheroscleroprotective, cardioprotective and hepatoprotective functions. The hypocholesterolemic functions of chlorogenic acid are probably due to the increase in fatty acids unitization in liver via the up-regulation of peroxisome proliferation-activated receptor α mRNA.

Although zebrafish has become a popular animal model for drug discovery and screening, drug metabolism in zebrafish remains largely unknown. In this study, we probed the metabolic capability of zebrafish larvae with calycosin, one of the major isoflavone constituents of Radix Astragali that was previously demonstrated to be angiogenic in the zebrafish model. The metabolism of calycosin and accumulation of its metabolites in zebrafish larvae were determined using an LC-MS/MS method. Calycosin showed a slow but steady decrease from the culture medium as well as a steady accumulation in zebrafish larvae. Calycosin underwent major conjugation and minor oxidation in zebrafish larvae. A total of ten calycosin metabolites formed from glucuronidation, glucosylation, sulfation, oxidation or a combination of two of these metabolisms were identified, most of which were reported for the first time. Most metabolites increased steadily in the larvae over 24-h experimental period. The dominant phase II conjugation of calycosin in zebrafish larvae matched well with existing knowledge of isoflavone metabolism in mammalians. The findings shed a light in certain degree of similarity of phase II drug metabolism between zebrafish larvae and mammals and warrant further investigation on feasibility of adopting the zebrafish larvae as a whole-organism model for examining drug metabolism.

Astragaloside IV (AS-IV) is a natural product isolated from the Chinese medical herb, Radix Astragali, which has been reported to be a potential candidate for treating diseases associated with abnormal angiogenesis; however, the effect of AS-IV on angiogenesis and its underlying mechanisms are yet to be fully elucidated. In the present study, we investigated the angiogenic effect of AS-IV in vitro using human umbilical vein endothelial cells (HUVECs), and in vivo using zebrafish. AS-IV was found to stimulate the proliferation and migration of HUVECs in an XTT assay and a wound healing migration assay, respectively. Moreover, AS-IV stimulated the invasive ability of HUVECs and significantly increased the mean tube length of HUVECs in Matrigel. AS-IV induced an angiogenic response in HUVECs and enhanced mRNA expression of vascular endothelial growth factor (VEGF) and a VEGF receptor known as kinase‑domain region/fetal liver kinase-1/VEGF receptor 2 (KDR/Flk-1/VEGFR2), as well as activation of Akt as demonstrated by quantitative real-time PCR and Western blot analysis, respectively. The AS-IV-induced proliferation of HUVECs was capable of being suppressed by a KDR inhibitor (SU5416) and an Akt inhibitor (SH-6). AS-IV also rescued blood vessel loss in Tg (fli-1:EGFP) zebrafish. Altogether, our results suggest that AS-IV exerts potential pro-angiogenic effects in vitro and in vivo, and that its pro-angiogenic activity probably involves both VEGF- and Akt-dependent signaling pathways.

Grifola frondosa (Polyporaceae), maitake, is a widely consumed edible mushroom in some Asian countries. The fruit bodies and mycelia of maitake have shown different bioactive compounds with anticancer and other therapeutic properties.This study evaluated three chemically modified maitake polysaccharide-peptides' (MPSP) adjuvant effect (in vivo) and anticancer activity (in vitro growth inhibitory effect) compared with crude MPSP from G. frondosa.We investigated the possibility of enhancing the adjuvant effect and anticancer effect of crude MPSP by using simple chemical modification methods to convert crude MPSP to phosphorylated, acetylated or esterified MPSPs. The adjuvant effect and growth inhibitory effect were evaluated by C6 cell inoculated rat model with cyclophosphamide (CPA) treatment and in vitro cell viability assay, respectively.All four tested MPSPs showed significant adjuvant effect to CPA treatment on rats inoculated with C6 cancer cells. In addition, an obvious growth inhibitory effect was observed in C6 cancer cells but not in normal brain cells treated with various forms of MPSPs. Only phosphorylation could significantly (p 0.05) improve the adjuvant effect (in vivo) and growth inhibitory effect. A same rank order (phosphorylated MPSPesterified MPSP ≥ acetylated MPSP ≥ crude MPSP) of efficacy was observed in both the in vivo and in vitro assays.This study showed chemical phosphorylation could markedly enhance both adjuvant effects and growth inhibitory effects. This study demonstrated the feasibility of enhancing the efficacy of MPSP by using a simple chemical modification method, and this provides a foundation for future study in this area.

UNLABELLED The extract of Curcuma longa, better known as turmeric, was orally administered to experimental rats that were fed a high-cholesterol diet to investigate whether it could regulate plasma lipids and cholesterol levels and possibly improve hepatic conditions. With turmeric supplements, rats showed a significant decrease in total plasma cholesterol and low-density lipoprotein cholesterol but an increase in high-density lipoprotein cholesterol when compared with rats that were fed a high-cholesterol diet alone. Fatty liver developed in hypercholesterolemic rats with the high-cholesterol diet treatment, and this condition was markedly improved when rats were provided with turmeric supplements at 100 mg/kg or 300 mg/kg of body mass. The turmeric treatment resulted in a significant decrease in the total amount of hepatic lipid. Histological staining of liver tissues with Sudan III and hematoxylin showed that rats fed with a high-cholesterol diet alone had more and larger granular fat bodies than rats having turmeric extract supplementation in their high-cholesterol diet. Reverse-transcription polymerase chain reaction was used to assess the expression levels of enzymes involved in fat metabolism and cellular homeostasis in experimental rat livers. The results showed that rats fed a high-cholesterol diet supplemented with turmeric extract had a significant increase in the expression of cholesterol 7 α-hydroxylase, hemeoxygenase 1, and low-density lipoprotein receptors but a significant decrease in 3-hydroxy-3-methyl-glutaryl-CoA reductase level when compared with rats fed a normal or high-cholesterol diet, showing that turmeric prevents hypercholesterolemia and the formation of fatty liver by the modulation of expressions of enzymes that are important to cholesterol metabolism. PRACTICAL APPLICATION Turmeric may be considered a functional food for regulating plasma cholesterol levels and preventing the development of fatty liver in people who frequently consume a high-cholesterol diet.

To investigate the involvement of Cl⁻ channels in endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation in rat mesenteric arteries.Cl⁻ channel and K(ir) channel activities were studied using whole-cell patch clamping in rat mesenteric arterial smooth muscle cells. Isometric tension of arterial rings was measured in organ chambers.The volume-activated Cl⁻ current in rat mesenteric arterial smooth muscle cells was abolished by Cl⁻ channel blockers NPPB or DIDS. The EDHF-mediated vasorelaxation was potentiated by NPPB and DIDS. The EDHF response was diminished by a combination of apamin and charybdotoxin, which agreed with the hypothesis that EDHF response involves the release of K(+) via the Ca²(+)-activated K(+) channels in endothelial cells. The elevation of K(+) concentration in bathing solution from 1.2 mmol/L to 11.2 mmol/L induced an arterial relaxation, which was abolished by the combination of BaCl₂ and ouabain. It is consistent to the hypothesis that K(+) activates K(+)/Na(+)-ATPase and inward rectifier K(+) (K(ir)) channels, leading to the hyperpolarization and relaxation of vascular smooth muscle. The K(+)-induced relaxation was augmented by NPPB, DIDS, or withdrawal of Cl⁻ from the bathing solution, which could be reversed by BaCl₂, but not ouabain. The potentiating effect of Cl⁻ channel blockers on K(+)-induced relaxation was probably due to the interaction between Cl⁻ channels and K(ir) channels. Moreover, the K(+)-induced relaxation was potentiated when the arteries were incubated in hyperosmotic solution, which is known to inhibit volume-activated Cl⁻ channels.The inhibition of Cl⁻ channels, particularly the volume-activated Cl⁻ channels, may potentiate the EDHF-induced vasorelaxation through the K(ir) channels.

Background: Angiogenesis plays an important role in a wide range of physiological processes, and many diseases are associated with the dysregulation of angiogenesis. Radix Astragali is a Chinese medicinal herb commonly used for treating cardiovascular disorders and has been shown to possess angiogenic effect in previous studies but its active constituent and underlying mechanism remain unclear. The present study investigates the angiogenic effects of calycosin, a major isoflavonoid isolated from Radix Astragali, in vitro and in vivo.Methodology: Tg(fli1:EGFP) and Tg(fli1:nEGFP) transgenic zebrafish embryos were treated with different concentrations of calycosin (10, 30, 100 μM) from 72 hpf to 96 hpf prior morphological observation and angiogenesis phenotypes assessment. Zebrafish embryos were exposed to calycosin (10, 100 μM) from 72 hpf to 78 hpf before gene-expression analysis. The effects of VEGFR tyrosine kinase inhibitor on calycosin-induced angiogenesis were studied using 72 hpf Tg(fli1:EGFP) and Tg(fli1:nEGFP) zebrafish embryos. The pro-angiogenic effects of calycosin were compared with raloxifene and tamoxifen in 72 hpf Tg(fli1:EGFP) zebrafish embryos. The binding affinities of calycosin to estrogen receptors (ERs) were evaluated by cell-free and cell-based estrogen receptor binding assays. Human umbilical vein endothelial cell cultures (HUVEC) were pretreated with different concentrations of calycosin (3, 10, 30, 100 mM) for 48 h then tested for cell viability and tube formation. The role of MAPK signaling in calycosin-induced angiogenesis was evaluated using western blotting. Conclusion: Calycosin was shown to induce angiogenesis in human umbilical vein endothelial cell cultures (HUVEC) in vitro and zebrafish embryos in vivo via the up-regulation of vascular endothelial growth factor (VEGF), VEGFR1 and VEGFR2 mRNA expression. It was demonstrated that calycosin acted similar to other selective estrogen receptor modulators (SERMs), such as raloxifene and tamoxifen, by displaying selective potency and affinity to estrogen receptors ERa and ERb. Our results further indicated that calycosin promotes angiogenesis via activation of MAPK with the involvement of ERK1/2 and ER. Together, this study revealed, for the first time, that calycosin acts as a selective estrogen receptor modulator (SERM) to promote angiogenesis, at least in part through VEGF-VEGFR2 and MAPK signaling pathways. © 2010 Tang et al., published_or_final_version

Epoxyeicosatrienoic acids (EETs) induce vasorelaxation, probably through G protein-coupled receptors. The identity of these receptors is unclear, but it has been reported that EETs may bind to peroxisome proliferator activated receptors (PPARs) and E-prostanoid (EP) receptors. Therefore, we studied whether PPARs or EP receptors were involved in 14,15-EET-induced vasorelaxation. Isometric tensions of rat mesenteric arteries were measured. The vasorelaxant effect of 14,15-EET was inhibited by NF449 (G(s)-protein inhibitor), Rp-cAMP (cAMP antagonist) and KT5720 (PKA inhibitor), suggesting that the effect of 14,15-EET was mediated through G(s) protein-coupled receptors which were linked to the cAMP/PKA-dependent pathway. Pretreatments with MK886 (PPAR(alpha) antagonist) and GW9662 (PPAR(gamma) antagonist) did not influence 14,15-EET-induced vasorelaxation. The vasorelaxant effect of 14,15-EET was inhibited by AH6809 (EP(2) receptor antagonist), whereas SC19220 (EP(1) receptor antagonist), L798106 (EP(3) receptor antagonist) and GW627368X (EP(4) receptor antagonist) had no effect. The effect of 14,15-EET and the mechanism involved was mimicked by prostaglandin E(2) (an EP(2) receptor agonist). The 14,15-EET-induced relaxation was slightly potentiated in the presence of indomethacin (cyclooxygenase inhibitor which block PGE(2) synthesis). Binding study showed that the amount of 14,15-EET bound to the cell membrane of rat mesenteric arterial smooth muscle cells was much higher than that bound to the nuclear membrane. The binding of 14,15-EET to the cell membrane was attenuated by AH6809 and siRNA against EP(2) receptors. In conclusion, our study has demonstrated that 14,15-EET exerts relaxant effects on rat mesenteric arteries, at least partly via the stimulation of EP(2) receptors. This subsequently leads to activation of cAMP/PKA-dependent pathway in vascular smooth muscle cells.

To determine the expression of glial fibrillary acidic protein(GFAP) and vascular endothelial growth factor(VEGF) in the hippocampus of rats with Alzheimer's disease(AD), and to determine the effect of butylphthalide on them and its significance.Sixty male adult rats were randomly divided into a model group, a Butylphthalide group, and a control group. AD models were established by injecting beta-amyloid protein 1-42 into the hippocampus of rats. Sixty days later,the rats were sacrificed and both sides of the hippocampus were sectioned for immunohistochemistry.Positive cells of GFAP in the hippocampus of the model group increased and the expression of VEGF decreased statistically, compared with the control group(P0.01). The positive cells of GFAP in the hippocampus of the butylphthalide group decreased and the expression of VEGF increased significantly, compared with the model group(P0.05).Butylphthalide may protect the neuron-vascular unit of the hippocampus of Alzheimer model rats by inhibiting the expression of GFAP and increasing the expression of VEGF.

Angiogenesis plays an important role in the development of neoplastic diseases such as cancer. Resveratrol and its derivatives exert antiangiogenic effects, but the mechanisms of their actions remain unclear. The aim of this study was to evaluate the antiangiogenic activity of resveratrol and its derivative trans-3,5,4'-trimethoxystilbene in vitro using human umbilical vein endothelial cells (HUVECs) and in vivo using transgenic zebrafish, and to clarify their mechanisms of action in zebrafish by gene expression analysis of the vascular endothelial growth factor (VEGF) receptor (VEGFR2/KDR) and cell-cycle analysis. trans-3,5,4'-Trimethoxystilbene showed significantly more potent antiangiogenic activity than that of resveratrol in both assays. In zebrafish, trans-3,5,4'-trimethoxystilbene caused intersegmental vessel regression and downregulated VEGFR2 mRNA expression. Trans-3,5,4'-trimethoxystilbene also induced G2/M cell-cycle arrest, most specifically in endothelial cells of zebrafish embryos. We propose that the antiangiogenic and vascular-targeting activities of trans-3,5,4'-trimethoxystilbene result from the downregulation of VEGFR2 expression and cell-cycle arrest at G2/M phase.

To determine the effect of butylphthalide on the expressions of p38 mitogen-activated protein kinase and extra-cellular signal regulated kinases (ERKs) in the brain tissue of rats with Alzheimer's disease (AD).Sixty male adult rats were randomly divided to AD model group, butylphthalide group, and control group (n=20). AD models were established by injecting beta-amyloid protein 1-42 into the hippocampus of rats. Sixty days later, the learning and memory abilities of the rats were evaluated using Y-maze test, and the expressions of p38 and ERKs in the brain tissue of the rats were measured by immunohistochemistry. RESULTS Compared with the control group, the rats in AD model group exhibited significantly reduced learning and memory abilities, increased expressions of P38 in the hippocampus and lowered expression of ERK in the cortex (P0.01). In comparison with the model group, the rats in the butylphthalide group showed significantly decreased P38-positive cells in the hippocampus and increased expression of ERK in the cortex (P0.01).Butylphthalide improves the learning and memory abilities of rats with experimental AD, the mechanism of which may involve inhibition of P38 expression and enhancement of ERK expression in the brain tissues.

Folic acid supplementation provides beneficial effects on endothelial functions in patients with hyperhomocysteinemia. However, its effects on vascular functions under diabetic conditions are largely unknown. Therefore, the effect(s) of folic acid (5.7 and 71 microg/kg/day for 4 weeks) on aortic relaxation was investigated using obese/diabetic (+db/+db) mice and lean littermate (+db/+m) mice. Acetylcholine-induced relaxation in +db/+db mice was less than that observed in +db/+m mice. The reduced relaxation in +db/+db mice was restored by consumption of 71 microg/kg folic acid. Acetylcholine-induced relaxation (with and without folic acid treatment) was sensitive to N(G)-nitro-L-arginine methyl ester, 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one, geldanamycin and triciribine. In addition, acetylcholine-induced relaxation was attenuated by resistin. The plasma level of resistin in +db/+db mice was sevenfold higher than that measured in +db/+m mice, and the elevated plasma level of resistin in +db/+db mice was reduced by 25% after treatment with 71 microg/kg folic acid. Folic acid slightly increased the ratio of reduced glutathione to oxidized glutathione in +db/+db mice. Moreover, folic acid caused a reduction in PTEN (phosphatase and tensin homolog deleted on chromosome 10) expression, an increase in the phosphorylation of endothelial nitric oxide synthase (eNOS(Ser1177)) and Akt(Ser473), and an enhanced interaction of heat shock protein 90 (HSP90) with eNOS in both strains, with greater magnitude observed in +db/+db mice. In conclusion, folic acid consumption improved blunted acetylcholine-induced relaxation in +db/+db mice. The mechanism may be, at least partly, attributed to enhancement of PI3K/HSP90/eNOS/Akt cascade, reduction in plasma resistin level, down-regulation of PTEN and slight modification of oxidative state.

Puerarin, a major isoflavonoid compound from the Chinese herb, Ge-gen (Pueraria lobata), has effective treatment on myocardial and cerebral ischemia, glaucoma and sudden deafness in clinical setting in China. Our present work showed that puerarin (50, 150, 450 microM) concentration-dependently inhibited phenylephrine or KCl-induced contraction only in endothelium-intact rat aortic rings. In Ca(2+)-free solution, the antivasoconstriction of puerarin on phenylephrine was totally deprived. N (G)-nitro-L-arginine methyl ester, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, indomethacin and the three K(+) channel blockers, glibenclamide, tetraethylammonium and Ba(2+) displayed significant inhibitory effects on the antivasoconstriction of puerarin. 8-bromo-cGMP significantly strengthened the action of puerarin. Puerarin (10-160 microM) concentration-dependently induced the NO production in the rat aortic cells. These findings suggested that the antivasoconstriction elicited by puerarin is endothelium-dependent. NO/NO-cGMP pathway, PGI(2) and the opening of K(+) channels sensitive to glibenclamide, tetraethylammonium, and Ba(2+), which might be triggered by the extracellular Ca(2+) influx in the endothelium, appear to contribute to the antivasoconstriction of puerarin.

Background The use of abacavir has been linked with increased cardiovascular risk in patients with human immunodeficiency virus infection; however, the mechanism involved remains unclear. We hypothesize that abacavir may impair endothelial function. In addition, based on the structural similarity between abacavir and adenosine, we propose that abacavir may affect vascular contractility through endogenous adenosine release or adenosine receptors in blood vessels. Methods The relaxation effect of abacavir on rat basilar arteries was studied using the myograph technique. Cyclic GMP and AMP levels were measured by immunoassay. The effects of abacavir on nucleoside transporters were studied using radiolabeled nucleoside uptake experiments. Ecto-5′ nucleotidase activity was determined by measuring the generation of inorganic phosphate using adenosine monophosphate as the substrate. Results Abacavir induced the relaxation of rat basilar arteries in a concentration-dependent manner. This relaxation was abolished when endothelium was removed. In addition, the relaxation was diminished by the nitric oxide synthase inhibitor, L-NAME, the guanylyl cyclase inhibitor, ODQ, and the protein kinase G inhibitor, KT5820. Abacavir also increased the cGMP level in rat basilar arteries. Abacavir-induced relaxation was also abolished by adenosine A2 receptor blockers. However, abacavir had no effect on ecto-5’ nucleotidase and nucleoside transporters. Short-term and long-term treatment of abacavir did not affect acetylcholine-induced relaxation in rat basilar arteries. Conclusion Abacavir induces acute endothelium-dependent relaxation of rat basilar arteries, probably through the activation of adenosine A2 receptors in endothelial cells, which subsequently leads to the release of nitric oxide, resulting in activation of the cyclic guanosine monophosphate/protein kinase G-dependent pathway in vascular smooth muscle cells. It is speculated that abacavir-induced cardiovascular risk may not be related to endothelial dysfunction as abacavir does not impair relaxation of blood vessels. The most likely explanation of increased cardiovascular risk may be increased platelet aggregation as suggested by other studies.

The cough and emetic reflexes involve a synchronized firing of motor neurones involved in respiratory control. Tachykinin NK1 receptor antagonists and 5-HT1A receptor agonists are examples of centrally acting drugs that reduce cough and emesis. In the present studies, therefore, we examined the possibility that other classes of drugs known to reducing cough have anti-emetic properties to prevent emesis induced by diverse challenges. We examined the potential of codeine (1-10 mg/kg), baclofen (1-10 mg/kg), scopolamine (0.3-10 mg/kg), diphenhydramine (1-10 mg/kg), imperialine (1-30 mg/kg) and verticine (0.3-3 mg/kg) to inhibit emesis induced by nicotine (5 mg/kg, s.c.), copper sulphate (120 mg/kg, intragastric), and provocative motion (4 cm horizontal displacement, delivered at 1 Hz) in Suncus murinus (house musk shrew). Only codeine had broad inhibitory properties (P0.05) to antagonize emesis induced by all challenges with ID50 values ranging from 1.2 to 2.3 mg/kg. Baclofen antagonized emesis induced by nicotine (maximum reduction was 44.9%, P0.05) and motion (maximum reduction was 97.3%, P0.01), but potentiated copper sulphate-induced emesis (maximum potentiation was 73.0%, P0.05). Scopolamine antagonized copper sulphate-induced emesis (maximum reduction was 61.2%, P0.05) and imperialine antagonized nicotine-induced emesis (maximum reduction was 30.2%, P0.01), but verticine potentiated motion-induced emesis (maximum potentiation was 60.0%, P0.05). Diphenhydramine did not significantly reduce emesis induced by any of the challenges (P0.05). In conclusion, codeine has broad inhibitory anti-emetic actions but a known ability to reduce coughing does not necessarily predict broad inhibitory anti-emetic properties.

Functional foods have become an increasingly popular alternative to prevent diseases and maintain body health status. Gui-ling-gao (GLG, also known as turtle jelly) is a well-known traditional functional food popular in Southern China and Hong Kong. This study aimed to investigate the antioxidative and anti-apoptotic effects of GLG, a traditional Chinese functional food, on preventing oxidative stress-induced injury in H9c2 cardiomyocytes. In this study, the antioxidative capacities of GLG were measured by using both a cell-free assay [2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl assay] and biological methods [2,2'-azobis(2-amidinopropane)-induced haemolysis assay and H(2)O(2)-induced cell damage on H9c2 cardiomyocytes]. Additionally, the total phenolic content was measured using the Folin-Ciocalteu method. Furthermore, the anti-apoptotic effect of GLG was evaluated by nuclear staining and a DNA fragmentation assay. GLG was found to have good antioxidant activities and high total phenolic content. In H(2)O(2)-induced cell damage on H9c2 cells, GLG was demonstrated to ameliorate the apoptotic effects, such as nuclear condensations, increased intracellular caspase-3 activity and inter-nucleosomal DNA cleavage, induced by H(2)O(2). The present study demonstrated for the first time that GLG possesses anti-apoptotic potential in vitro and this effect may be mediated, in part, by its antioxidative function. Additionally, the antioxidative capacities of GLG were proved both chemically and biologically. This study provides scientific evidence to prove the anecdotal health-beneficial claim that the consumption of GLG could help the body to handle endogenous toxicants such as free radicals.

Angiogenesis plays an important role in a wide range of physiological processes and many diseases are associated with the dysregulation of angiogenesis. The commonly used Chinese herbal medicine Radix Astragali (known as Huang qi in Chinese) is a potential candidate for treating this type of disease. Calycosin, a major isoflavonoid in Radix Astragali, was identified in our earlier study and shown to induce angiogenesis in human umbilical vein endothelial cells (HUVEC) in vitro and in zebrafish embryos in vivo. Using zebrafish as a testing model, we investigated the angiogenic effect of calycosin on the subintestinal vessels (SIVs) in zebrafish embryos. Our findings using transcriptional profiling by deep sequencing, and confirmed by quantitative real-time PCR (qPCR), demonstrate that calycosin modulated vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF) and ErbB signaling pathways. The inhibitory effects of calycosin-induced phenotypic responses by several pathway-specific inhibitors (VRI, SU5402, MEK1/2 Inhibitor, Wortmannin and LY294002) further identified the potential involvement of VEGF(R) and FGF(R) signaling pathways in the angiogenic activities of calycosin. We present a comprehensive framework of study using fluorescence microscopy, transcriptomics and qPCR to demonstrate the proangiogenic effects of calycosin in vivo. The data have elucidated the connection between morphological observations and genomic evidence, indicating the potential roles of several key signaling pathways in angiogenesis.