Genome-wide identification, subcellular localization, and expression analysis of the phosphatidyl ethanolamine-binding protein family reveals the candidates involved in flowering and yield regulation of Tartary buckwheat (Fagopyrum tataricum).

Background: PEBP (phosphatidyl ethanolamine-binding protein) is widely found in eukaryotes including plants, animals and microorganisms. In plants, the PEBP family plays vital roles in regulating flowering time and morphogenesis and is highly associated to agronomic traits and yields of crops, which has been identified and characterized in many plant species but not well studied in Tartary buckwheat (Fagopyrum tataricum Gaertn.), an important coarse food grain with medicinal value. Methods: Genome-wide analysis of FtPEBP gene family members in Tartary buckwheat was performed using bioinformatic tools. Subcellular localization analysis was performed by confocal microscopy. The expression levels of these genes in leaf and inflorescence samples were analyzed using qRT-PCR. Results: Fourteen Fagopyrum tataricum PEBP (FtPEBP) genes were identified and divided into three sub-clades according to their phylogenetic relationships. Subcellular localization analysis of the FtPEBP proteins in tobacco leaves indicated that FT- and TFL-GFP fusion proteins were localized in both the nucleus and cytoplasm. Gene structure analysis showed that most FtPEBP genes contain four exons and three introns. FtPEBP genes are unevenly distributed in Tartary buckwheat chromosomes. Three tandem repeats were found among FtFT5/FtFT6, FtMFT1/FtMFT2 and FtTFL4/FtTFL5. Five orthologous gene pairs were detected between F. tataricum and F. esculentum. Seven light-responsive, nine hormone-related and four stress-responsive elements were detected in FtPEBPs promoters. We used real-time PCR to investigate the expression levels of FtPEBPs among two flowering-type cultivars at floral transition time. We found FtFT1/FtFT3 were highly expressed in leaf and young inflorescence of early-flowering type, whereas they were expressed at very low levels in late-flowering type cultivars. Thus, we deduced that FtFT1/FtFT3 may be positive regulators for flowering and yield of Tartary buckwheat. These results lay an important foundation for further studies on the functions of FtPEBP genes which may be utilized for yield improvement.

Vitamin D status and the risk of neuromyelitis optica spectrum disorders: A systematic review and meta-analysis.

BACKGROUND: Previous studies have linked vitamin D deficiency with autoimmune diseases, and recent research has found low vitamin D levels in neuromyelitis optica spectrum disorder (NMOSD) patients. We aimed to determine the variances in serum 25(OH)D levels between NMOSD patients and healthy controls. METHODS: We searched English and Chinese databases (PubMed, Embase, Cochrane Library, Web of Science, CBM, CNKI, WanFang Med, VIP) for observational studies related to serum 25(OH)D levels in NMOSD patients published up to August 24, 2023. We included studies with healthy controls and compared serum 25(OH)D levels between NMOSD patients and controls. We computed the mean difference (MD) and 95% confidence interval (CI) for continuous variables to evaluate serum 25(OH)D levels and combined odds ratios (ORs) and 95% CIs for dichotomized 25(OH)D data. RESULTS: Six papers were selected for meta-analysis, including 794 participants (347 in the NMOSD group and 447 in the healthy control group). Meta-analysis showed significantly lower serum 25(OH)D levels in the NMOSD group (MD: -7.83, 95 % CI: -10.99 to -4.68). The risk of 25(OH)D deficiency was 23.36 times higher in the NMOSD group (OR: 23.36, 95 % CI: 0.85 to 640.76, p = 0.06>0.05), with a 94 % occurrence rate. There was no significant difference in the risk of having sufficient 25(OH)D between the groups (p = 0.12>0.05). CONCLUSION: NMOSD patients have lower serum 25(OH)D levels than healthy controls. However, the current research results do not provide evidence for a causal relationship between serum 25(OH)D levels and the onset of NMOSD. Routine vitamin D supplementation may be advantageous for patients with NMOSD.

Ferroxidase-like and antibacterial activity of PtCu alloy nanoparticles.

Many metal nanoparticles are reported to have intrinsic enzyme-like activities and offer great potential in chemical and biomedical applications. In this study, PtCu alloy nanoparticles (NPs), synthesized through hydrothermal treatment of Cu2+ and Pt2+ in an aqueous solution, were evaluated for ferroxidase-like and antibacterial activity. Electron spin resonance (ESR) spectroscopy and colorimetric methods were used to demonstrate that PtCu NPs exhibited strong ferroxidase-like activity in a weakly acidic environment and that this activity was not affected by the presence of most other ions, except silver. Based on the color reaction of salicylic acid in the presence of Fe3+, we tested the ferroxidase-like activity of PtCu NPs to specifically detect Fe2+ in a solution of an oral iron supplement and compared these results with data acquired from atomic absorption spectroscopy and the phenanthroline colorimetric method. The results showed that the newly developed PtCu NPs detection method was equivalent to or better than the other two methods used for Fe2+ detection. The antibacterial experiments showed that PtCu NPs have strong antibacterial activity against Staphylococcus aureus and Escherichia coli. Herein, we demonstrate that the peroxidase-like activity of PtCu NPs can catalyze H2O2 and generate hydroxyl radicals, which may elucidate the antibacterial activity of the PtCu NPs against S. aureus and E. coli. These results showed that PtCu NPs exhibited both ferroxidase- and peroxidase-like activity and that they may serve as convenient and efficient NPs for the detection of Fe2+ and for antibacterial applications.

Effects of noble metal nanoparticles on the hydroxyl radical scavenging ability of dietary antioxidants.

Noble metal nanoparticles (NPs) have been widely used in many consumer products. Their effects on the antioxidant activity of commercial dietary supplements have not been well evaluated. In this study, we examined the effects of gold (Au NPs), silver (Ag NPs), platinum (Pt NPs), and palladium (Pd NPs) on the hydroxyl radical (·OH) scavenging ability of three dietary supplements vitamin C (L-ascorbic acid, AA), (-)-epigallocatechin gallate (EGCG), and gallic acid (GA). By electron spin resonance (ESR) spin-trapping measurement, the results show that these noble metal NPs can inhibit the hydroxyl radical scavenging ability of these dietary supplements.

Efficacy and Safety of Danshen Compound Tablets in Preventing Thalidomide-Associated Thromboembolism in Patients with Multiple Myeloma: A Multicenter Retrospective Study.

BACKGROUND Currently available antithrombotic prophylaxis is not perfectly reliable in elderly patients. The aim of this retrospective study was to evaluate the efficacy and safety of Compound Danshen Tablet (CDT) in preventing thromboembolism in multiple myeloma (MM) patients treated with thalidomide-based regimens. MATERIAL AND METHODS MM patients treated with thalidomide-based regimens were retrospectively reviewed between January 2008 and March 2015. Patients were categorized into 3 cohorts based on thromboembolic prophylaxis used: CDT, Warfarin Tablet, and no prophylaxis. Venous thromboembolism (VTE), other adverse effects (AEs), and the changes of D-dimer and fibrinogen levels were monitored. RESULTS Seven out of 313 MM patients (2.24%) developed venous thrombosis events (VTE) in this retrospective study, all clustering in the no prophylaxis cohort. Three patients of the Warfarin cohort (3.19%) experienced hemorrhage. Neither VTE events nor serious AEs were observed in the CDT cohort. Following Compound Danshen or Warfarin treatment for 3 months, the D-dimer and fibrinogen levels (in particular the D-dimer level) (all P<0.05), were obviously decreased relative to their respective baselines and the no prophylaxis cohort. In contrast, the 2 blotting parameters were significantly increased in the no prophylaxis cohort relative to the baseline level (All P<0.05), and were even higher in the patients experiencing VTE compared to the no VTE patients (P<0.0001 and P=0.016, respectively). CONCLUSIONS Our findings indicate CDT is an effective therapy for preventing VTE in MM patients treated with thalidomide-based regimens, and is well tolerated in long-term use.

Effect of silver nanomaterials on the activity of thiol-containing antioxidants.

The use of nanomaterials in consumer products is rapidly expanding. In most studies, nanomaterials are examined as isolated ingredients. However, consumer products such as foods, cosmetics, and dietary supplements are complex chemical matrixes. Therefore, interactions between nanomaterials and other components of the product must be investigated to ensure the product's performance and safety. Silver nanomaterials are increasingly being used in food packaging as antimicrobial agents. Thiol-containing compounds, such as reduced glutathione (GSH), cysteine, and dihydrolipoic acid, are used as antioxidants in many consumer products. In the current study, we have investigated the interaction between silver nanomaterials and thiol-containing antioxidants. The selected Ag nanomaterials were Ag coated with citrate, Ag coated with poly(vinylpyrrolidone), and Au nanorods coated with Ag in a core/shell structure. We observed direct quenching of the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) by all three Ag nanomaterials to varying degrees. The Ag nanomaterials also reduced the quenching of DPPH by GSH to varying degrees. In addition, we determined that the mixture of GSH and Au@Ag nanorods held at 37 °C was less effective at quenching azo radical than at ambient temperature. Furthermore, we determined that Au@Ag nanorods significantly reduced the ability of GSH and cysteine to quench hydroxyl and superoxide radicals. The work presented here demonstrates the importance of examining the chemical interactions between nanomaterials used in products and physiologically important antioxidants.

Phototoxicity of kava - formation of reactive oxygen species leading to lipid peroxidation and DNA damage.

Kava is one of the most widely sold herbal dietary supplements in the United States. It has been reported that, besides exhibiting hepatotoxicity, kava also possesses photosensitivity and induces dermopathy in humans. In this study, we determined that UVA irradiation of kava in the presence of a lipid, methyl linoleate, generated lipid peroxidation which was mediated by singlet oxygen generated during photoirradiation. The six major kavalactones(yangonin, 7,8-dihydrokawa in, kawain, 7,8-dihydromethysticin, methysticin, and 5,6-dehydrokawain) were also studied in parallel; only 5,6-dehydrokawain and yangonin-induced a low level of lipid peroxidation. UVA irradiation of kava in human HaCaT skin keratinocytes induced cytotoxicity which was mediated by oxidative stress, led to DNA strand cleavage, and produced 8-hydroxy-2'-deoxyguanosine (8-OHdG) adduct. Study by the electron spin resonance (ESR) method revealed that UVA irradiation of kava produced singlet oxygen and carbon-centered radicals. The overall results suggest that kava is photocytotoxic and photogenotoxic, both mediated by free radicals generated during photoirradiation.

Dual role of selected antioxidants found in dietary supplements: crossover between anti- and pro-oxidant activities in the presence of copper.

Overproduction of reactive oxygen species (ROS) in vivo can result in damage associated with many aging-associated diseases. Defenses against ROS that have evolved include antioxidant enzymes, such as superoxide dismutases, peroxidases, and catalases, which can scavenge ROS. In addition, endogenous and dietary antioxidants play an important role in moderating damage associated with ROS. In this study, we use four common dietary antioxidants to demonstrate that, in the presence of copper (cupric sulfate and cupric gluconate) and physiologically relevant levels of hydrogen peroxide, these antioxidants can also act as pro-oxidants by producing hydroxyl radicals. Using electron spin resonance (ESR) spin trapping techniques, we demonstrate that the level of hydroxyl radical formation is a function of the pH of the medium and the relative amounts of antioxidant and copper. On the basis of the level of hydroxyl radical formation, the relative pro-oxidant potential of these antioxidants is cysteine > ascorbate > EGCG > GSH. It has been reported that copper sequestered by protein ligands, as happens in vivo, loses its redox activity (diminishing/abolishing the formation of free radicals). However, in the presence of hydrogen peroxide, cysteine and GSH efficiently react with cupric sulfate sequestered with bovine serum albumin to generate hydroxyl radicals. Overall, the results demonstrate that in the presence of copper, endogenous and dietary antioxidants can also exhibit pro-oxidative activity.

Isolation of antioxidants from Psoralea corylifolia fruits using high-speed counter-current chromatography guided by thin layer chromatography-antioxidant autographic assay.

A combinative method using high-speed counter-current chromatography (HSCCC) and thin layer chromatography (TLC) as an antioxidant autographic assay was developed to separate antioxidant components from the fruits of Psoralea corylifolia. Under the guidance of TLC bioautography, eight compounds including five flavonoids and three coumarins were successfully separated from the fruits of P. corylifolia by HSCCC with an optimized two-phase solvent system, n-hexane-ethyl acetate-methanol-water (1:1.1:1.3:1, v/v/v/v). The separation produced 5.91mg psoralen, 6.26mg isopsoralen, 3.19mg psoralidin, 0.92mg corylifol A, and 2.43mg bavachinin with corresponding purities of 99.5, 99.8, 99.4, 96.4, and 99.0%, as well as three sub-fractions, in a single run from 250mg ethyl acetate fraction of P. corylifolia extract. Following an additional clean-up step by preparative TLC, 0.4mg 8-prenyldaidzein (purity 91.7%), 4.18mg neobavaisoflavone (purity 97.4%) and 4.36mg isobavachalcone (purity 96.8%) were separated from the three individual sub-fractions. The structures of the isolated compounds were identified by (1)H NMR and (13)C NMR. The results of antioxidant activity estimation by electron spin resonance (ESR) method showed that psoralidin was the most active antioxidant with an IC50 value of 44.7microM. This is the first report on simultaneous separation of eight compounds from P. corylifolia by HSCCC.

Grape seed proanthocyanidins ameliorate Doxorubicin-induced cardiotoxicity.

Doxorubicin (Dox) is one of the most widely used and successful chemotherapeutic antitumor drugs. Its clinical application is highly limited due to its cumulative dose-related cardiotoxicity. Proposed mechanisms include the generation of reactive oxygen species (ROS)-mediated oxidative stress. Therefore, reducing oxidative stress should be protective against Dox-induced cardiotoxicity. To determine whether antioxidant, grape seed proanthocyanidin extract (GSPE) attenuates Dox-induced ROS generation and protects cardiomyocytes from Dox-induced oxidant injury, cultured primary cardiomyocytes were treated with doxorubicin (Dox, 10 microM) alone or GSPE (50 microg/ml) with Dox (10 microM) for 24 hours. Dox increased intracellular ROS production as measured by 6-carboxy-2',7'-dichlorodihydrofluorescein diacetate, induced significant cell death as assessed by propidium iodide, and declined the redox ratio of reduced glutathione (GSH)/oxidized glutathione (GSSG) and disrupted mitochondrial membrane potential as determined by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethlbenzimidazole-carbocyanide iodine (JC-1). Analysis of agarose gel electrophoresis revealed Dox-induced nuclear DNA damage with the ladder like fragmentation. GSPE treatment suppressed those alterations. Electron Spin Resonance (ESR) spectroscopy data also showed that GSPE strongly scavenged hydroxyl radical, superoxide and DPPH radicals. Together, these findings indicate that GSPE in combination with Dox has protective effect against Dox-induced toxicity in cardiomyocytes, which may be in part attributed to its antioxidative activity. Importantly, flow cytometric analysis demonstrated that co-treatment of Dox and GSPE did not decrease the proliferation-inhibitory effect of Dox in MCF-7 human breast carcinoma cells. Thus, GSPE may be a promising adjuvant to prevent cardiotoxicity without interfering with antineoplastic activity during chemotherapeutic treatment with Dox.

Regulation of influenza virus-caused oxidative stress by Kegan Liyan oral prescription, as monitored by ascorbyl radical ESR signals.

To study the oxidative stress level of the influenza virus A FM1 subset-infected mouse in intranasal inhalation as a model, we employ an ascorbyl radical's ESR (electron spin resonance) spectrum as an oxidative stress biomarker. These infected mice were pretreated with Ribavirin, ascorbic acid, superoxide dismutase (SOD) or Kegan Liyan oral prescription (KGLY, proprietary Chinese medicine for influenza and common cold) in the stomach tube for 3 days, and then followed by the virus-infecting for 4 days. On the 4th day, samples were collected. It is recognized the strength of ascorbyl radical's ESR signal (A(-.)) (a(H4 = 0.177) Gauss, g = 2.00517) denotes oxidative stress level in vivo and in vitro. The magnitude of ESR spectrum (28.65 +/- 10.71 AU) in mice infected with influenza virus was significantly higher than those of healthy control mice (19.10 +/- 3.61 AU). Serum A(-.) in mice treated with Ribavirin, ascorbic acid, SOD and KGLY declined to 19.70 +/- 6.05, 18.50 +/- 2.93 and 16.25 +/- 3.59, 18.40 +/- 2.14 AU respectively. It is close to A(-.) signal height in healthy controls via down-regulation of the influenza virus-caused oxidative stress level getting decline in the lung index of pneumonia as compare to those of untreated healthy and the influenza virus infected mice pneumonia. It is well known that SOD can prevent the influenza virus pneumonia enhancing mouse survival rate; Ribavirin can treat viral diseases. Data from this study suggested that KGLY may indirectly relieve influenza virus-infected pneumonia via down- regulation of virus caused oxidative stress coupled with a redox reaction cascade as ribavirin, ascorbic acid and SOD.

Effects of wheat antioxidants on oxygen diffusion-concentration products in liposomes and mRNA levels of HMG-CoA reductase and cholesterol 7alpha-hydroxylase in primary rat hepatocytes.

Three wheat antioxidant fractions were investigated for their potential effects on oxygen diffusion-concentration products in liposomes prepared with egg yolk phosphatidycholine (yolk PC) and rat liver PC (liver PC), using the electron spin resonance (ESR) oximetry method with 2,2'-azobis(2-aminopropane) dihydrochloride (AAPH) and 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN) as radical generators. Both water-soluble wheat antioxidant (WWA) and the second lipophilic antioxidant (LWA2) fractions were able to inhibit oxygen diffusion-concentration product induced by either AAPH or AMVN. The first lipophilic wheat antioxidant (LWA1) fraction only showed antioxidant activity in yolk PC liposomes with AAPH as the radical initiator but had pro-oxidant activity under other testing conditions. Both liposome composition and radical initiator altered the antioxidative properties of WWA, LWA1, and LWA2. WWA also showed the strongest DPPH(*) scavenging capacity on a per grain weight basis. HPLC analysis showed that WWA had a much higher level of total phenolic acids, which may partially explain their antioxidant properties. In addition, wheat antioxidants significantly down-regulated the mRNA of HMG-CoA reductase, the key enzyme for cholesterol biosynthesis, and up-regulated the mRNA of cholesterol 7alpha-hydroxylase (CYP7A1), the key enzyme for cholesterol metabolism, in primary rat hepatocytes. These data indicated the potential of wheat antioxidants in reducing the risk of atherosclerosis through multimechanisms.

Effects of metal ions, catechins, and their interactions on prostate cancer.

Prostate cancer is threatening human health heavily, for its causes are related to diet, genetic factors, and lifestyle. Metal ions, which are necessary to our health, are important factors inducing many diseases including prostate cancer in the condition of absence or excess. Epidemiological and laboratory studies provide convincing evidence that green tea prevents and cures prostate cancer. Practically, interactions of catechins, which are the main bioactive components in green tea or GTP, with metal ions have a new aspect to investigate their mechanism in preventing and curing prostate cancer. In the present paper, we summarize some research about the effects of catechins with metal ions related to prostate cancer and their interactions on prostate cancer.

Role of Zn2+ in epigallocatechin gallate affecting the growth of PC-3 cells.

Green tea has chemo-preventive effects to human carcinoma including prostate cancer. Epigallocatechin gallate (EGCG) is the major active component in green tea. Zn(2+) is indispensable to our health, and plays an important role in the normal function and pathology of the prostate gland, and might be a good marker for diagnosing prostate cancer. Effects of Zn(2+), EGCG and their interactions on the growth of androgen-insensitive prostate cancer cell (PC-3) were investigated in the present paper. The results show that Zn(2+) and EGCG inhibited the growth of PC-3 cells in a time- and dose-dependent manner, but effects of interactions of EGCG with Zn(2+) were extremely dependent on their concentrations and added orders. Inhibitory effects of Zn(2+) were significantly decreased in the presence of EGCG on PC-3 cell growth. Therefore, we hypothesize that complexation of EGCG with Zn(2+) might be responsible for the observed decrease of the bioactivities of Zn(2+) against PC-3 cells.

Fatty acids in tea shoots (Camellia sinensis (L.) O. Kuntze) and their effects on the growth of retinal RF/6A endothelial cell lines.

Chemo-protective effects of tea on ocular diseases were recorded in Chinese pharmacopoeia about 2000 years ago by eating tea. In the present study, contents of fatty acids (FAs) in tea shoots were determined by capillary GC; and the growth of RF/6A cells was also investigated by exposure to various representative FAs existing in tea shoots with pathologically relevant concentrations (40-500 microM) by ameliorated MTT assay and flow cytometry. Electron spin resonance (ESR) was used to measure oxygen consumption and investigate the free radical scavenging ability of linoleic acid (LA). Results showed that the most abundant long chain FAs were palmitic, linoleic, and alpha-linolenic acid in tea shoots; some RF/6A cells became suspended in culture medium treated by a high dose of both saturated and unsaturated FAs, but no apoptosis was observed. Moreover, it seemed that those FAs with different structure had various effects on the cell proliferation at their relatively low concentrations, LA expressed antioxidant activity in this study, which might be an important mechanism on the protection of eyes.

Effects of interactions of EGCG and Cd(2+) on the growth of PC-3 cells and their mechanisms.

The preventive and therapeutic effects of a major component of catechins of green tea, epigallocatechin-3-gallate (EGCG), on prostate cancer have been demonstrated in many studies. It is well known that metal ions are necessary for human health, but an imbalance in metal ions metabolism can lead to many diseases including prostate cancer. Understanding the interactions of EGCG with metal ions might elucidate its mechanism in preventing and curing prostate cancer. The present study focused on the effects of Cd(2+) and EGCG on the growth of androgen-insensitive prostate cancer cell PC-3 investigated by MTT assay, the effects of EGCG and Cd(2+) on absorption of Cd(2+) and Zn(2+) by PC-3 cells were detected by atomic absorption spectroscopy (AAS), and the interactions of EGCG with Cd(2+) were determined by distribution coefficient and UV-Vis spectroscopy detection. The results showed that Cd(2+) suppressed viability of PC-3 cells in concentration- and time-dependent manner, and EGCG enhanced the effect of Cd(2+) on PC-3 cells. EGCG was shown to decrease the absorption Cd(2+) and increase the absorption of Zn(2+) by PC-3 cells, while the effects of Cd(2+) on the absorption of Cd(2+) and Zn(2+) were opposite to that of EGCG. In the presence of both EGCG and Cd(2+), absorption of Cd(2+) and Zn(2+) by PC-3 cells was dependent on concentrations of EGCG, Cd(2+) and its order of addition. Results from the distribution coefficient determination and UV-Vis spectroscopy analysis indicated that Cd(2+) might affect conformation of EGCG, while no complex of EGCG with Cd(2+) was observed in the system.

American ginseng berry extract and ginsenoside Re attenuate cisplatin-induced kaolin intake in rats.

PURPOSE: Cisplatin, a chemotherapeutic agent, causes significant nausea and vomiting. It is postulated that cisplatin-induced oxidant stress may be responsible for these symptoms. We tested whether pretreatment with American ginseng berry extract (AGBE), an herb with potent antioxidant capacity, and one of its active antioxidant constituents, ginsenoside Re, could counter cisplatin-induced emesis using a rat pica model. METHODS: In rats, exposure to emetic stimuli such as cisplatin causes significant kaolin intake, a phenomenon called pica. We therefore measured cisplatin-induced kaolin intake as an indicator of the emetic response. Rats were pretreated with vehicle, AGBE (dose range 50-150 mg/kg, IP) or ginsenoside Re (2 and 5 mg/kg, IP). Rats were treated with cisplatin (3 mg/kg, IP) 30 min later. Kaolin intake, food intake, and body weight were measured every 24 h for 120 h. Additionally, the free radical scavenging activity of AGBE was measured in vitro using ESR spectroscopy. RESULTS: A significant dose-response relationship was observed between increasing doses of pretreatment with AGBE and reduction in cisplatin-induced pica. Kaolin intake was maximally attenuated by AGBE at a dose of 100 mg/kg. Food intake also improved significantly at this dose (P<0.05). Pretreatment with ginsenoside Re (5 mg/kg) also decreased kaolin intake (P<0.05). In vitro studies demonstrated a concentration-response relationship between AGBE and its ability to scavenge superoxide and hydroxyl radicals. CONCLUSION: Pretreatment with AGBE and its major constituent, Re, attenuated cisplatin-induced pica, and demonstrated potential for the treatment of chemotherapy-induced nausea and vomiting. Significant recovery of food intake further strengthens the conclusion that AGBE may exert an antinausea/antiemetic effect.

Oral administration of Crataegus flavonoids protects against ischemia/reperfusion brain damage in gerbils.

Stroke is the third leading cause of death as dementia is a main symptom of Alzheimer's disease. One of the important mechanisms in the pathogeny of stroke is free radical production during the reperfusion period, therefore the effects of a type of natural antioxidant, i.e. Crataegus flavonoids (CF), on brain ischemic insults were investigated in Mongolian gerbil stroke model. Results showed that pretreatment of the animals with CF decreased reactive oxygen species (ROS) production, thiobarbituric acid reactive substances content, and nitrite/nitrate concentration in brain homogenate, increased the brain homogenate-associated antioxidant level in a dose-dependent manner. CF pretreatment increased the amount of biologically available NO by scavenging of superoxide anion produced during reperfusion. At same time, in the process of ischemia/reperfusion brain damage, the content of nitrite/nitrate (the end product of NO) increased, and of NO detected by ESR decreased. Oral pretreatment with CF decreased the nitrite/nitrate content in the brain homogenate and increased the biologically available NO concentration in a dose-dependent manner. The increasing effect of antioxidant on NO might be due to its scavenging effect on superoxide anion, which could react with NO into peroxynitrite. iNOS was implied in delayed neuron death after brain ischemic damage and it was found that pretreatment with CF could decrease the protein level of tumor necrosis factor (TNF)-alpha and nuclear factor-kappa B (NF-kappaB), and increase the mRNA level of NOS estimated by western blotting and RT-PCR. More neurons survived and fewer cells suffered apoptosis in the hippocampal CA1 region of CF treated animal brain. These results suggest that oral administration of this antioxidant increases the antioxidant level in the brain and protects the brain against delayed cell death caused by ischemia/reperfusion injury.

Synergistic effect of Scutellaria baicalensis and grape seed proanthocyanidins on scavenging reactive oxygen species in vitro.

Scutellaria baicalensis (SbE) is a commonly used Chinese herb medicine and grape seed proanthocyanidins is a popular herbal supplement in the United States. Both herbs have been shown to possess potent antioxidant effects. Using an in vitro model to produce the reactive oxygen species (ROS) generation (H2O2/FeSO4 for hydroxyl radicals, xanthine/xanthine oxidase for suproxide), we observed that Scutellaria baicalensis and grape seed proanthocyanidins acted synergistically to scavenge ROS. Our data suggest that a combination of these two herbs can potentially enhance their antioxidant efficacy, allowing lower dosages of each drug to be used. This has the advantage of avoiding possible side effects that may arise when higher doses of a single herb are used in an attempt to achieve a maximum degree of antioxidant activity.

Effects of antioxidant herbs on chemotherapy-induced nausea and vomiting in a rat-pica model.

Nausea and vomiting are significant adverse effects of chemotherapeutic agents like cisplatin, and cause significant patient morbidity. Cisplatin treatment results in oxidant gut injury, which is postulated to be the primary cause of nausea and vomiting. We evaluated the effects of two antioxidant herbs, Scutellaria baicalensis and American ginseng berry, on cisplatin-induced nausea and vomiting using a rat model. Rats react to emetic or nausea-producing stimuli, such as cisplatin, with altered feeding habits, manifested by increased kaolin consumption (pica). We measured pica in rats to quantify cisplatin-induced nausea. We observed that pretreatment of rats with S. baicalensis or ginseng berry extracts resulted in a significant reduction in cisplatin-induced pica. The in vitro free radical scavenging ability of the herbal extract observed in the study, further confirmed the antioxidant action of the herb. We conclude that herbal antioxidants may have a role in attenuating cisplatin-induced nausea and vomiting.