Combining thermosonication microstress and pineapple peel extract addition to achieve quality and post-acidification control in yogurt fermentation.

This work investigated the effects of the combined use of thermosonication-preconditioned lactic acid bacteria (LAB) with the addition of ultrasound-assisted pineapple peel extracts (UU group) on the post-acidification potential, physicochemical and functional qualities of yogurt products, aimed at achieving prolonged preservation and enhancing functional attributes. Accordingly, the physical-chemical features, adhesion properties, and sensory profiles, acidification kinetics, the contents of major organic acids, and antioxidant activities of the differentially processed yogurts during refrigeration were characterized. Following a 14-day chilled storage process, UU group exhibited acidity levels of 0.5-2 oT lower than the control group and a higher lactose content of 0.07 mg/ml as well as unmodified adhesion potential, indicating that the proposed combination method efficiently inhibited post-acidification and delayed lactose metabolism without leading to significant impairment of the probiotic properties. The results of physicochemical analysis showed no significant changes in viscosity, hardness, and color of yogurt. Furthermore, the total phenolic content of UU-treated samples was 98 µg/mL, 1.78 times higher than that of the control, corresponding with the significantly lower IC50 values of DPPH and ABTS radical scavenging activities of the UU group than those of the control group. Observations by fluorescence inverted microscopy demonstrated the obvious adhesion phenomenon with no significant difference found among differentially prepared yogurts. The results of targeted metabolomics indicated the proposed combination strategy significantly modified the microbial metabolism, leading to the delayed utilization of lactose and the inhibited conversion into glucose during post-fermentation, as well as the decreased lactic acid production and a notable shift towards the formation of relatively weak acids such as succinic acid and citric acid. This study confirmed the feasibility of thermosonication-preconditioned LAB inocula, in combination with the use of natural active components from fruit processing byproducts, to alleviate post-acidification in yogurt and to enhance its antioxidant activities as well as simultaneously maintaining sensory features.

Gut microbial metabolite butyrate improves anticancer therapy by regulating intracellular calcium homeostasis.

BACKGROUND AND AIMS: Gut microbiota are recognized to be important for anticancer therapy, yet the underlying mechanism is not clear. Here, through the analysis of clinical samples, we identify the mechanism by which the gut microbial metabolite butyrate inhibits HCC and then explore new strategies for HCC treatment. APPROACH AND RESULTS: In our study, we demonstrate that gut microbial metabolite butyrate improves anticancer therapy efficacy by regulating intracellular calcium homeostasis. Using liquid chromatography-mass spectrometry analysis, we found that butyrate metabolism is activated in HCC patients compared with healthy individuals. Butyrate levels are lower in the plasma of HCC patients by gas chromatography-mass spectrometry (GC-MS) analysis. Butyrate supplementation or depletion of short-chain Acyl-CoA dehydrogenase (SCAD) gene (ACADS), encoding a key enzyme for butyrate metabolism, significantly inhibits HCC proliferation and metastasis. The profiling analysis of genes upregulated by butyrate supplementation or ACADS knockdown reveals that calcium signaling pathway is activated, leading to dysregulation of intracellular calcium homeostasis and production of reactive oxygen species. Butyrate supplementation improves the therapy efficacy of a tyrosine kinase inhibitor sorafenib. On the basis of these findings, we developed butyrate and sorafenib coencapsulated mPEG-PLGA-PLL nanoparticles coated with anti-GPC3 antibody (BS@PEAL-GPC3) to prolong the retention time of drugs and enhance drug targeting, leading to high anticancer efficacy. BS@PEAL-GPC3 nanoparticles significantly reduce HCC progression. In addition, BS@PEAL-GPC3 nanoparticles display excellent HCC targeting with excellent safety. CONCLUSIONS: In conclusion, our findings provide new insight into the mechanism by which the gut microbial metabolites inhibit HCC progression, suggesting a translatable therapeutics approach to enhance the clinical targeted therapeutic efficacy.

Encapsulation of resveratrol-loaded Pickering emulsions in alginate/pectin hydrogel beads: Improved stability and modification of digestive behavior in the gastrointestinal tract.

In this study, alginate/pectin hydrogel beads were prepared with different mixing ratios (9:1, 8:2, 7:3, 6:4, and 5:5) to encapsulate resveratrol-loaded Pickering emulsions using Ca2+ crosslinking. The system with a suitable ratio of pectin and alginate can enhance the encapsulation efficiency and loading capacity. Scanning electron microscopy (SEM) study confirmed that the hydrogel beads were spherical, in which Pickering emulsion was distributed evenly within the polymer network. Fourier Transform Infrared Spectroscopy (FTIR) study indicated that the hydrogel beads were formed by physical cross-linking. X-ray diffraction (XRD) study demonstrated that resveratrol existed in hydrogel beads with an amorphous or dissolved form. Besides, the stability and antioxidant capacity suggested that hydrogel beads could offer protection to resveratrol by preventing degradation through environmental stresses, while maintaining its antioxidant capacity. Importantly, hydrogels significantly reduced the release of free fatty acids and resveratrol during in vitro digestion compared to emulsions, especially with the appropriate ratio of sodium alginate and pectin. Overall, Pickering emulsions-loaded alginate/pectin hydrogel beads could offer a novel option for the preparation of low-calorie foods and a potential substitute model for controlling the release of free fatty acids contributing to the transportation of resveratrol.

The Influence of Comminuting Methods on the Structure, Morphology, and Calcium Release of Chicken Bones.

This work aimed at assessing the influence of comminuting methods, including colloid mill, planetary ball mill and dynamic high-pressure microfluidization on the chemical composition, particle properties, morphology and calcium release of chicken bone. The results showed that planetary ball mill and dynamic high-pressure microfluidization could reduce the particle size of bone powder, and the particle size of sample treated by dynamic high-pressure microfluidization reached 446 nm. Chicken bone particles were negatively charged, and the absolute value of zeta potential was significantly reduced after milling treatments. Furthermore, X-ray diffraction and Fourier-transform infrared spectroscopy (FTIR) analysis indicated that the planetary ball mill and dynamic high-pressure microfluidization processes presented no significant effect on the internal chemical structure of bone particles. Compared with the other groups, samples treated by dynamic high-pressure microfluidization released more calcium ions, which was related to the significant effects on surface calcium composition and reducing particle size. Therefore, dynamic high-pressure microfluidization has a great potential in the processing of bone-derived products, particularly for the design and development of bone-derived product with high calcium bioaccessibility.

Antimicrobial, antioxidant and physical properties of chitosan film containing Akebia trifoliata (Thunb.) Koidz. peel extract/montmorillonite and its application.

A novel active packaging film was prepared in this study that incorporated Akebia trifoliata (Thunb.) Koidz. peel extracts (APE) and montmorillonite (MMT) into chitosan (CH) films. Compared with the pure CH film, the CH/APE film showed significantly higher tensile strength, elongation at break, UV light resistance, and antibacterial activity; the CH/MMT film displayed significant increases in contact angle, antioxidant activity, oxygen permeability, and thermal stability. SEM and AFM analyses showed that the additions were well-distributed into the CH matrix, but MMT induced a more compact and rougher structure. The CH-based film formula was optimized using the single-factor test and Box-Behnken design and was 0.15% MMT, 0.15% APE, and 1.50% CH. Besides, the optimized coating was applied in the postharvest preservation of A. trifoliata fruits, which yielded a significant effect on the delaying crack and mature of the fruits during 35 days of storage at 5 °C.

Ultrasound as a Promising Tool for the Green Extraction of Specialized Metabolites from Some Culinary Spices.

Spices are a popular food of plant origin, rich in various phytochemicals and recognized for their numerous properties. The aim of the study was to evaluate the antioxidant and antimicrobial activity, as well as the content of specialized metabolites, of aqueous extracts of three spice species--garlic (Allium sativum L.), ginger (Zingiber officinalle L.) and turmeric (Curcuma longa L.)--prepared by green extraction methods. Ultrasound treatment increased the chromaticity parameter b value of turmeric and ginger extracts, thus indicating a higher yellow color predominantly due to curcuminoids characteristic of these species. Ultrasound-assisted extraction significantly increased the content of total soluble solids, phenolic compounds, total carotenoids and vitamin C. The temperature of the system was also an important factor, with the highest (70 °C) conditions in ultrasound-assisted extraction having a positive effect on thermolabile compounds (vitamin C, phenolics, total carotenoids). For example, turmeric extract treated with ultrasound at 70 °C had up to a 67% higher vitamin C content and a 69.4% higher total carotenoid content compared to samples treated conventionally at the same temperature, while ginger extracts had up to 40% higher total phenols. All different concentrations of spice extracts were not sufficient for complete inhibition of pathogenic bacterial strains of Salmonella, L. monocytogenes and S. aureus; however, only garlic extracts had an effect on slowing down the growth and number of L. monocytogenes colonies. Spice extracts obtained by ultrasonic treatment contained a significantly higher level of bioactive compounds and antioxidant capacity, suggesting that the extracts obtained have significant nutritional potential and thus a significant possibility for phytotherapeutic uses.

Targeted sequencing reveals the mutational landscape responsible for sorafenib therapy in advanced hepatocellular carcinoma.

Rationale: The existence of primary and acquired drug resistance is the main obstacle for the effect of multi-kinase inhibitor sorafenib and regorafenib in advanced hepatocellular carcinoma (HCC). However, plenty of patients did not significantly benefit from sorafenib treatment and little is known about the mechanism of drug resistance. Methods: Laser capture microdissection was used to acquire matched normal liver and tumor tissues on formalin-fixed paraffin-embedded specimens collected before sorafenib therapy from the first surgery of 119 HCC patients. Ultra-deep sequencing (~1000×) targeting whole exons of 440 genes in microdissected specimens and siRNA screen in 7 cell lines were performed to find mutations associated with differential responses to sorafenib. Patient-derived xenograft models were employed to determine the role of TP53 in response to sorafenib. Lentiviruses harboring wild-type and c.G52C-mutant OCT4 were applied to explore the function of OCT4 in resistance to sorafenib. ChIP-PCR assay for analysis of OCT4 transcriptional activity was performed to explore the affinity with the KITLG promoter. Statistical analyses were used to associate levels of p53 and OCT4 with tumor features and patient outcomes. Results: Total 1,050 somatic mutations and 26 significant driver genes were identified. SiRNA screening in 7 HCC cell lines was further performed to identify mutations associated with differential responses to sorafenib. A recurrent nonsynonymous mutation c.G52C in OCT4 (OCT4mut) was strongly associated with good response to sorafenib, whereas the stop-gain mutation in TP53 showed the opposite outcome both in vitro and in vivo. OCT4wt-induced stem cell factor (encoded by KITLG gene, SCF) expression and cross-activation of c-KIT/FLT3-BRAF signals were identified indispensably for sorafenib resistance, which could be reversed by the combination of c-KIT tyrosine kinase inhibitors or neutralizing antibody against SCF. Mechanistically, an OCT4 binding site in upstream of KITLG promoter was identified with a higher affinity to wildtype of OCT4 rather than G52C-mutant form, which is indispensable for OCT4-induced expression of KITLG and sorafenib resistance. Conclusion: Our study reported a novel somatic mutation in OCT4 (c.G52C) responsible for the sorafenib effect, and also shed new light on the treatment of HCC through the combination of specific tyrosine kinase inhibitors according to individual genetic patterns.

Comparative anti-arthritic investigation of iridoid glycosides and crocetin derivatives from Gardenia jasminoides Ellis in Freund's complete adjuvant-induced arthritis in rats.

BACKGROUND: Discovering novel compounds with higher activities is a key aim of natural products research. Gardenia jasminoides Ellis is a herb with anti-inflammatory properties. Iridoid glycosides (mainly geniposide) and crocetin derivatives (crocins) are the two major active constituents in this herb and are considered its active ingredients. However, which components are responsible for the anti-inflammatory properties of gardenia have remained to be investigated. PURPOSE: Here, we prepared total iridoid glycocides (TIG) and total crocins (TC) from G. jasminoides Ellis, determined their main chemical constituents, and performed animal studies to evaluate their anti-adjuvant arthritis activities, thus, proposing a reasonable mechenism to explain the anti-inflammatory activities of the active components in this herbal remedy. STUDY DESIGN: TIG and TC were prepared by using HPD-100 macroporous resin, and characterized by UHPLC-DAD-MS and UV-Vis spectrophotometer. Then, freund's complete adjuvant-injected rats underwent drug treatments with TIG (160 mg/kg) and TC (160 mg/kg) for 14 days, and their ankle diameters were measured. Moreover, X-ray radiographs of the adjuvant injected hind paws were evaluated. Finally, histopathological examinations of the ankle joints, spleens and thymus were carried out to evaluate inflammatory reactions, and immunohistochemical measurements were conducted to evaluate TNF-α and TGF-ß1 expression in the ankle joint of the rats. RESULTS: The chemical composition determination of the current study showed that TIG was mainly composed of geniposide and TC was a fraction predominantly with crocin-1, crocin-2 and crocin-3. Calculation of results showed that TIG and TC contained 58.2% total iridoid glycosides and 54.7% total crocins, respectively. Our study suggested TIG and TC treatments markedly decreased paw swelling and ankle diameters of AA rats (both p < 0.05). The radiological analysis showed that administration of TIG and TC ameliorated bone destruction, and reduced the radiological bone destruction scores (TIG p < 0.05, TC p>0.05). Moreover, data from histological assessment demonstrated considerable mitigation of inflammation in the joints (both p < 0.01), spleen and thymus of AA rats treated with TIG and TC. TNF-α and TGF-ß1 protein expression according to immunohistochemistry staining also supported the anti-arthritis activities of TIG and TC (TNF-α: TIG p < 0.01 and TC p < 0.05, TGF-ß1: TIG p < 0.01 and TC p>0.05). CONCLUSION: In the current study, fractionation of gardenia prior to further in vivo investigation has for the first time provided reasonable explanation for the anti-inflammatory activity of this herbal remedy. Our study showed that both TIG and TC from gardenia have anti-inflammatory properties. Overall, these experimental findings suggest that gardenia could be regarded as a potential therapeutic target for arthritis. However, as geniposide has a higher content than crocins in this herbal drug, TIG (mainly geniposide) seems to be primarily responsible for the anti-inflammatory properties of gardenia. Taken together, this maiden attempt demonstrated that TIG (mainly geniposide) is more important in evaluating the anti-inflammatory activity of G. jasminoides Ellis.

Safety assessment of sorafenib in Chinese patients with unresectable hepatocellular carcinoma: subgroup analysis of the GIDEON study.

BACKGROUND: This study aimed to investigate the safety of sorafenib for the treatment of unresectable hepatocellular carcinoma in Chinese patients. METHODS: A subgroup of 345 Chinese patients from the international database of the Global Investigation of therapeutic DEcisions in hepatocellular carcinoma and Of its treatment with sorafeNib (GIDEON) study was included in this analysis. Safety assessment measures were adverse events (AEs) and serious adverse events (SAEs) graded using the National Cancer Institute Common Terminology Criteria version 3.0. RESULTS: Of 331 evaluable patients, 98% started sorafenib at 800 mg/day. The median treatment duration was 22 weeks (range, 0.1-116 weeks), and median overall survival (OS) was 322 days (10.7 months). Approximately 50% of patients had at least one adverse event, and 6% had grade 3-4 adverse events. Drug-related adverse events were experienced by 29% of patients, and 3.6% had grade 3-4 drug-related adverse events. Overall, 23% of patients (n = 77) experienced serious adverse events, among which only 1 event was drug-related (0.3%). No differences in overall adverse events, serious adverse events, and deaths were observed between Child-Pugh A and Child-Pugh B patients. The most frequent drug-related adverse events were dermatological/skin (24%), hand-foot skin reaction (20%), gastrointestinal (11%), and diarrhea (11%). The majority of adverse events occurred within 30 days of beginning sorafenib. CONCLUSION: Sorafenib has satisfactory efficacy and safety in Chinese Child-Pugh A and B patients with unresectable HCC using the recommended dosage of 800 mg/day, and the safety of sorafenib is not affected by liver function. Prophylaxis for gastrointestinal adverse events may help to decrease dose interruptions or discontinuation. TRIAL REGISTRATION: ClinicalTrials.gov ; Identifier: NCT00812175. Date of registration: December 19, 2008.

Multilayer emulsions as a strategy for linseed oil and α-lipoic acid micro-encapsulation: study on preparation and in vitro characterization.

BACKGROUND: Linseed oil and α-lipoic acid are bioactive ingredients, which play an important role in human nutrition and health. However, their application in functional foods is limited because of their instabilities and poor solubilities in hydrophilic matrices. Multilayer emulsions are particularly useful to protect encapsulated bioactive ingredients. The aim of this study was to fabricate multilayer emulsions by a high-pressure homogenization method to encapsulate linseed oil and α-lipoic acid simultaneously. Tween 20 and lecithin were used as surfactants to stabilize the oil droplets of primary emulsions. Multilayer emulsions were produced by using an electrostatic layer-by-layer deposition process of lecithin-chitosan membranes. RESULTS: Thermal treatment exhibited that chitosan encapsulation could improve the thermal stability of primary emulsions. During in vitro digestion, it was found that chitosan encapsulation had little effect on the lipolysis of linseed oil and bioaccessibility of α-lipoic acid. The oxidation stability of linseed oil in multilayer emulsions was improved effectively by chitosan encapsulation and α-lipoic acid. Chitosan encapsulation could inhibit the degradation of α-lipoic acid. A physical stability study indicated that multilayer emulsions had good centrifugal, dilution and storage stabilities. CONCLUSION: Multilayer emulsion is an effective delivery system to incorporate linseed oil and α-lipoic acid into functional foods and beverages. © 2018 Society of Chemical Industry.

Safety and efficacy of sorafenib therapy in patients with hepatocellular carcinoma: final outcome from the Chinese patient subset of the GIDEON study.

We report data from the final analysis of the Chinese subset of the GIDEON (the Global Investigation of therapeutic DEcisions in hepatocellular carcinoma and Of its treatment with sorafeNib) study, which evaluated the safety and efficacy of sorafenib in Child-Pugh A, B and C patients with unresectable hepatocellular carcinoma (uHCC) in real-life clinical practice. Patient demographics, disease characteristics and treatment history were recorded at enrollment; dose, adverse events (AEs) and efficacy were recorded at follow-up. Of the 338 evaluable patients, 98.5% started on 800 mg/day sorafenib, regardless of their Child-Pugh status. The median treatment duration (21.1 vs. 18.8 weeks) and median overall survival (322 vs 240 days) were longer in patients with Child-Pugh A compared with the Child-Pugh B, progression-free survival were 183 vs. 208 days, respectively). AEs (all grades) were comparable in the Child-Pugh B vs A group (56.3% vs. 50.4%, respectively), moreover, the Child-Pugh B group also had comparable rates of drug-related AEs (35.4% vs. 27.2%, respectively) and serious AEs (25.0% vs. 23.0%, respectively) compared with the Child-Pugh A group. The overall dosing strategy was consistent in Chinese patients across Child-Pugh subgroups. Tolerability and safety data suggest that Child-Pugh B patients might be safely treated with sorafenib. The findings from our study showed that safety profile of sorafenib in terms of rate and type of AEs is similar to the global international GIDEON study as well as other pivotal studies.

Endothelium-dependent and -independent vasorelaxant actions and mechanisms induced by total flavonoids of Elsholtzia splendens in rat aortas.

Elsholtzia splendens (ES) is, rich in flavonoids, used to repair copper contaminated soil in China, which has been reported to benefit cardiovascular systems as folk medicine. However, few direct evidences have been found to clarify the vasorelaxation effect of total flavonoids of ES (TFES). The vasoactive effect of TFES and its underlying mechanisms in rat thoracic aortas were investigated using the organ bath system. TFES (5-200mg/L) caused a concentration-dependent vasorelaxation in endothelium-intact rings, which was not abolished but significantly reduced by the removal of endothelium. The nitric oxide synthase (NOS) inhibitor N(ω)-nitro-l-arginine methyl ester (100µM) and the guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,2-α]quinoxalin-1-one (30µM) significantly blocked the endothelium-dependent vasorelaxation of TFES. Meanwhile, NOS activity in endothelium-intact aortas was concentration-dependently elevated by TFES. However, indomethacin (10µM) did not affect TFES-induced vasorelaxation. Endothelium-independent vasorelaxation of TFES was significantly attenuated by KATP channel blocker glibenclamide. The accumulative Ca(2+)-induced contraction in endothelium-denuded aortic rings primed with KCl or phenylephrine was markedly weakened by TFES. These results revealed that the NOS/NO/cGMP pathway is likely involved in the endothelium-dependent vasorelaxation induced by TFES, while activating KATP channel, inhibiting intracellular Ca(2+) release, blocking Ca(2+) channels and decreasing Ca(2+) influx into vascular smooth muscle cells might contribute to the endothelium-independent vasorelaxation conferred by TFES.

Induction of highly functional hepatocytes from human umbilical cord mesenchymal stem cells by HNF4α transduction.

AIM: To investigate the differentiation potential of human umbilical mesenchymal stem cells (HuMSCs) and the key factors that facilitate hepatic differentiation. METHODS: HuMSCs were induced to become hepatocyte-like cells according to a previously published protocol. The differentiation status of the hepatocyte-like cells was examined by observing the morphological changes under an inverted microscope and by immunofluorescence analysis. Hepatocyte nuclear factor 4 alpha (HNF4α) overexpression was achieved by plasmid transfection of the hepatocyte-like cells. The expression of proteins and genes of interest was then examined by Western blotting and reverse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. RESULTS: Our results demonstrated that HuMSCs can easily be induced into hepatocyte-like cells using a published differentiation protocol. The overexpression of HNF4α in the induced HuMSCs significantly enhanced the expression levels of hepatic-specific proteins and genes. HNF4α overexpression may be associated with liver-enriched transcription factor networks and the Wnt/ß-Catenin pathway. CONCLUSION: The overexpression of HNF4α improves the hepatic differentiation of HuMSCs and is a simple way to improve cellular sources for clinical applications.

Improvement of the oral bioavailability of coenzyme Q10 with lecithin nanocapsules.

Coenzyme Q10-loaded lecithin nanocapsules (CoQ10-LNCs), composed of a CoQ10/lecithin/ GTCC/glycerol aqueous solution, were prepared by high-pressure homogenization. The zeta potential of the CoQ10-LNCs above -60 mV was determined on a Malvern Zetasize 2000 (Malvern Instruments, UK). The spherical shape of the CoQ10-LNCs was observed by using freeze-fracture transmission electron microscopy (FF-TEM), and the particle size was found to be below 100 nm. The supercooled state of the CoQ10-LNCs was observed by differential scanning calorimetry (DSC). In an oral bioavailability study, the CoQ10 plasma level after administering CoQ10-LNCs was higher than that after administering a CoQ10 tablet over 24 hours, and the relative bioavailability of CoQ10 was improved to 176.6% in mice. Based on the above results, the LNC delivery system might be a potential vehicle for improving the oral bioavailability of CoQ10.

Total flavonoids of Flos Chrysanthemi protect arterial endothelial cells against oxidative stress.

ETHNOPHARMACOLOGICAL RELEVANCE: Total flavonoids of Flos Chrysanthemi (TFFC) are known to modulate vascular functions, but their effect on endothelial cells injured by oxidative stress is unknown. Our objective was to investigate the vasoprotective effect and mechanism of action of TFFC on rat mesenteric artery exposed to superoxide anions produced by pyrogallol. MATERIALS AND METHODS: The vasoprotective effect and mechanism of action of TFFC on primary cultured rat mesenteric arterial endothelial cells and small mesenteric arteries was investigated using small-vessel myography, fluorescent Ca(2+) measurement, fluorescent membrane potential measurement and oxidative fluorescent studies. RESULTS: Experiments using small-vessel myography of third-order rat mesenteric arterial rings showed that pretreatment with pyrogallol (10-1000µM), an auto-oxidizing source of superoxide anions, dose-dependently decreased ACh-induced endothelium-dependent relaxation. TFFC (2.5-320mg/L) evoked a concentration-dependent dilation (pD(2): 29.6±0.276mg/L), which was weakened by ChTX plus apamin. TFFC markedly attenuated the inhibition of vasorelaxation induced by pyrogallol (E(max) elevated from 50.4±7.36% to 86.2±3.61%, and pD(2) increased from 6.74±0.06 to 7.28±0.12). Furthermore, in primary cultured endothelial cells, fluorescent Ca(2+) measurement, fluorescent membrane potential measurement and oxidative fluorescent studies demonstrated that ACh-induced endothelial Ca(2+) influx and hyperpolarization were significantly weakened by the increased basal superoxide level induced by pyrogallol. When the endothelial cells were concurrently exposed to TFFC, the impairment effect of oxidative stress on ACh-induced Ca(2+) influx, hyperpolarization and vasorelaxation were attenuated due to its superoxide-lowering activity. CONCLUSION: This study shows that oxidative stress has a pronounced deleterious effect on EDHF-mediated vasorelaxation to ACh in rat mesenteric artery. TFFC has vasodilating effect and protects EDHF-mediated vasodilator reactivity from oxidative stress. Thus, our experiments suggest that TFFC is potentially useful for the development of therapeutic treatments for cardiovascular diseases associated with oxidative stress.

Betulinic acid ameliorates endothelium-dependent relaxation in L-NAME-induced hypertensive rats by reducing oxidative stress.

Zizyphi Spinosi semen (ZSS) is one of the most widely used traditional Chinese herbs with protective effects on the cardiovascular system. It is not clear whether betulinic acid (BA), the key active constituent of ZSS, has beneficial cardiovascular effects on N(ω)-nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertensive rats. The objective of this study was to investigate the effect of BA on endothelium-dependent vasorelaxation in isolated aortic rings from L-NAME-induced hypertensive rats and its underlying mechanisms. Male Sprague-Dawley rats were injected with L-NAME (15 mg/kg/d, i.p.) for 4 weeks to induce hypertension. After treatment with L-NAME for 2 weeks, rats with mean blood pressure >120 mm Hg measured by tail-cuff method were considered hypertensive and then injected with BA (0.8, 4, 20 mg/kg/d, i.p.) for the last 2 weeks. The effect of BA on the tension of rat thoracic aortic rings was measured in an organ bath system. The levels of nitric oxide (NO), reactive oxygen species (ROS), and the activity of superoxide dismutase (SOD) and nitric oxide synthase (NOS) in aortas were assayed. We found that BA (0.1-100 µM) evoked a concentration-dependent vasorelaxation in endothelium-intact normal rat aortic rings, which was significantly attenuated by pretreatment with L-NAME (100 µM) or methylene blue (MB, 10 µM), but not by indomethacin (10 µM). Pretreatment with EC(50) (1.67 µM) concentration of BA enhanced the acetylcholine (ACh)-induced vasorelaxation, which was also markedly reversed by both L-NAME and MB. The blood pressure in hypertensive rats increased to 135.22±5.38 mm Hg (P<0.01 vs. control group), which was markedly attenuated by high dose of BA. The ACh-induced vasorelaxation in hypertensive rat aortic rings was impaired, which was markedly improved by chronic treatment with BA (20 mg/kg/d) for 2 weeks. The increase of ROS level and the decrease of NO level, SOD and eNOS activities in hypertensive rat aortas were all markedly inhibited by BA. These results indicate that BA decreased blood pressure and improved ACh-induced endothelium-dependent vasorelaxation in L-NAME-induced hypertension rats, which may be mediated by reducing oxidative stress and retaining the bioavailability of NO in the cardiovascular system.

[Luteolin reduces cardiac dysfunctions in streptozotocin-induced diabetic rats].

OBJECTIVE: To investigate the effects of luteolin (Chinese Traditional Medicine) on cardiac functions and mitochondrial oxidative stress in streptozotocin (STZ)-induced diabetic rats. METHODS: Male SD rats were randomly divided into a normal control group, a luteolin control group, a diabetic group, and diabetic groups orally administered with a low dose (10 mg/(kg x d)) or a high dose of luteolin (100 mg/ (kg x d)) for eight weeks. The body weight, blood glucose, cardiac functions, left ventricular weight, myocardial collagen and reactive oxygen species (ROS) levels were assayed. The cardiac mitochondrial ROS level, superoxide dismutase (SOD) activity and the mitochondrial swelling were measured. RESULTS: Treatment with luteolin had no effect on the blood glucose but reduced the losing of body weight in diabetic rats. High dose of luteolin markedly reduced the ratio of ventricular weight and body weight, increased the left ventricular develop pressure, and decreased the left ventricular end diastolic pressure in diabetic rats. The myocardial levels of ROS and collagen, the cardiac mitochondrial ROS level, and the mitochondrial swelling in diabetic rats were all markedly reduced by high dose of luteolin. Furthermore, high dose of luteolin significantly increased the mitochondrial SOD activity in diabetic rat hearts. CONCLUSION: Treatment with luteolin for 8 weeks markedly improves the cardiac function, which may be related to reducing mitochondrial oxidative stress and mitochondrial swelling in diabetic rats.

[Auricularia auricular polysaccharide protects myocardium against ischemia/reperfusion injury].

OBJECTIVE: To determine whether auricularia auricular polysaccharide (AAP) protects heart against ischemia/reperfusion (1/ R) injury and its underlying mechanisms. METHODS: Male Sprague-Dawley rats, pretreated with AAP (50, 100, 200 mg/(kg x d), gastric perfusion) for 4 weeks, were used for Langendorff isolated heart perfusion. The hearts were subjected to global ischemia for 30 min followed by 120 min of reperfusion and the left ventricular hemodynamic parameters were measured. Formazan, a product of 2, 3, 5-triphenyl-tetrazolium chloride (TTC), which is proportional to myocardial viability, was measured at 490 nm, and the level of lactate dehydrogenase (LDH) in the coronary effluent was measured to evaluate the cardiac injury. The cardiac malondialdehyde (MDA), a product of lipid peroxidation, and superoxide dismutase (SOD) activity were determined after myocardial I/R. RESULTS: The pretreatment with AAP at 50, 100, 200/(kg d) for 4 weeks before I/R increased myocardial formazan content, reduced LDH release, improved the recovery of the left ventficular developed pressure, maximal rise rate of left ventricular pressure, and rate pressure product (left ventricular developed pressure multiplied by heart rate) attenuated the decrease of coronary flow during reperfusion. The cardiac protective effect of high dose AAP was more potent than that of compound radix salviae miltiorrhizae (CRSM, 4 ml/(kg x d), gastric perfusion for 4 weeks). Pretreatment with AAP (100 mg/(kg x d)) markedly inhibited the increase of MDA level and the decrease of SOD activity induced by I/R in myocardium. CONCLUSION: The findings indicate that in the isolated rat heart, AAP protects myocardium against ischemia/reperfusion injury via enhancing the activity of SOD and reducing lipid peroxidation in heart.

[Ginkgo biloba extract protects brain from ischemia/reperfusion injuries].

Ginkgo biloba extract (GBE) is one of the hot spots of drugs extracted from plants recently; it protects brain from ischemia/reperfusion injuries. The mechanism of protective effects includes antioxidation, free radicals clearance, inhibiting the release of excitatory amino acid, anti-inflammation, inhibiting neural apoptosis and other biological effects.

Antioxidant action of a Chrysanthemum morifolium extract protects rat brain against ischemia and reperfusion injury.

The present study evaluated the potential neuroprotective effect and underlying mechanism of the total flavones extracted from Chrysanthemum morifolium (TFCM) against ischemia/reperfusion (I/R) injury. An animal model of cerebral ischemia was established by occluding the right middle cerebral artery for 90 minutes followed by reperfusion for 22 hours. The neurobehavioral scores, infarct area, and hemispheric edema were evaluated. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and reactive oxygen species (ROS) level in brain were also measured. The results showed that pretreatment with TFCM significantly decreased the neurological deficit scores, percentage of infarction, and brain edema and attenuated the decrease in SOD activity, the elevation of MDA content, and the generation of ROS. In isolated brain mitochondria, Ca(2+)-induced swelling was attenuated by pretreatment with TFCM, and this effect was antagonized by atractyloside. These results showed that pretreatment with TFCM provides significant protection against cerebral I/R injury in rats by, at least in part, its antioxidant action and consequent inhibition of mitochondrial swelling.