Protective effects of antioxidative serotonin derivatives isolated from safflower against postischemic myocardial dysfunction

Acyl-Nω-methylserotonins and Branched-chain Acylserotonins in Lemon and Other Citrus Seeds—New Lipids with Antioxidant Properties and Potential Pharmacological Applications

We have found 15 previously unknown compounds in seeds of lemon and other citrus species, such as tangerine, grapefruit and pomelo. The structure of these compounds was characterized by HR–MS spectrometry, fluorescence spectroscopy and chemical synthesis. These compounds were predominantly long-chain (C20–C25), saturated acyl-Nω-methylserotonins with the main contribution of C22 and C24 homologues, usually accounting for about 40% and 30% of all acylserotonins, respectively. The other, previously undescribed, minor compounds were branched-chain acylserotonins, as well as normal-chain acylserotonins, recently found in baobab seed oil. Within the seed, acylserotonins were found nearly exclusively in the inner seed coat, where probably their biosynthesis proceeds. On the other hand, lemon seedlings contained only trace amounts of these compounds that were not found in adult leaves. The compounds identified in the present studies were shown to have antioxidant properties in vitro, using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. In the investigated reaction in hexane, Me-C22 and Me-C24-serotonins were less active than n-C22 and n-C24-serotonins and δ-tocopherol, while branched-chain acylserotonins (iso-C21 and -C25) showed higher antioxidant activity than all the normal-chain compounds. On the other hand, all these compounds showed a similar but considerably lower antioxidant activity in acetonitrile than in hexane.

Acylserotonins - a new class of plant lipids with antioxidant activity and potential pharmacological applications

During analysis of components of baobab (Adansonia digitata) seed oil, several new fluorescent compounds were detected in HPLC chromatograms that were not found previously in any seed oils investigated so far. After preparative isolation of these compounds, structural analysis by NMR spectroscopy, UHPLC-HR-MS, GC-FID and spectroscopic methods were applied and allowed identification of these substances as series of N-acylserotonins containing saturated C22 to C26 fatty acids with minor contribution of C27 to C30 homologues. The main component was N-lignocerylserotonin and the content of odd carbon-atom-number fatty acids was unusually high among the homologues. The suggested structure of the investigated compounds was additionally confirmed by their chemical synthesis. Synthetic N-acylserotonins showed pronounced inhibition of membrane lipid peroxidation of liposomes prepared from chloroplast lipids, especially when the peroxidation was initiated by a water-soluble azo-initiator, AIPH. Comparative studies of the reaction rate constants of the N-acylserotonins and tocopherols with a stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in solvents of different polarity revealed that N-acylserotonins showed similar activity to δ-tocopherol in this respect. The described compounds have been not reported before either in plants or in animals. This indicates that we have identified a new class of plant lipids with antioxidant properties that could have promising pharmacological activities.

Assessment of Metabolic Profiles in Florets of Carthamus Species Using Ultra-Performance Liquid Chromatography-Mass Spectrometry

The genus Carthamus is a diverse group of plants belonging to the family Compositae. Florets of Carthamus species exhibit various colors, including white, yellow, orange, and red, which are related to their metabolite compositions. We aimed to investigate the metabolites accumulated in florets of three wild (C. lanatus, C. palaestinus, and C. turkestanicus) and one cultivated (C. tinctorius) species of safflower at three developmental stages. Metabolites were extracted from freeze-dried florets using 70% methanol; qualification and quantification were carried out using liquid chromatography quadrupole time-of-flight mass spectrometry in positive and negative ion modes followed by extraction of the peaks. Fifty-six metabolites, including phenylpropanoids, chalcones, isoflavonoids, flavanones, flavonols, flavones, and other primary metabolites, were identified for the first time in safflower wild species. The orange florets contained high abundances of safflomin A, anhydrosafflor yellow B, and baimaside, whereas white/cream and light-yellow pigmented florets had high abundances of 1,5-dicaffeoylquinic acid, luteolin 7-O-glucuronide, and apigenin 7-O-β-D-glucuronide. The principal component analysis clearly distinguished the samples based on their pigment types, indicating that color is a dominant factor dictating the identity and amount of the metabolites. Pearson correlation data based on levels of metabolites showed that orange and yellow florets were significantly correlated to each other. White and cream pigmented species were also highly correlated. Comparison between three developmental stages of safflower wild species based on their metabolite profile showed inconsistent. The findings of this study broaden the current knowledge of safflower metabolism. The wide diversity of metabolites in safflower materials also helps in efforts to improve crop quality and agronomic traits.

The Chemistry and Health Benefits of Dietary Phenolamides

Phenolamides, also known as hydroxycinnamic acid amides or phenylamides, have been reported throughout the plant kingdom, while a few of these amine-conjugated hydroxycinnamic acids are unique in foods. The current knowledge of their specific functions in plant development and defense is readily available as is their biosynthesis; however, their functionality in humans is still largely unknown. Of the currently known phenolamides, the most common are avenanthramides, which are unique in oats and similar to the well-known drug Tranilast, which possess anti-inflammatory, antioxidant, anti-itch, and antiatherogenic activities. While recent data have brought to light more information regarding the other known phenolamides, such as hordatines, dimers of agmatine conjugated to hydroxycinnamic acid, and kukoamines, spermine-derived phenolamides, the information is still severely limited, leaving their potential health benefits to speculation. Herein, to highlight the importance of dietary phenolamides to human health, we review and summarize the four major subgroups of phenolamides, including their chemical structures, dietary sources, and reported health benefits. We believe that the studies on phenolamides are still in the infancy stage and additional health benefits of these phenolamides may yet be identified.

Oil and extract of safflower seed improve fructose induced metabolic syndrome through modulating the homeostasis of trace elements, TNF-α and fatty acids metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Safflower (Carthamus tinctorius) has many applications in folk medicine. Its oil is used traditionally to treat obesity and other metabolic disorders. The anti-hypercholesterolemic and antioxidant effects of this plant have been well documented, but the anti-inflammatory effects and its role on fatty acid oxidation and homeostasis of trace elements are not fully understood.

OBJECTIVE

The aim of this study was to evaluate the protective effects of different doses of oil and extract of safflower seed against fructose induced metabolic syndrome by investigating the homeostasis of trace elements, TNF-α, and fatty acids metabolism.

METHODS

Eighty adult male Sprague-Dawley rats were randomly divided into ten groups and treated daily for 16 weeks. At the end of the study, plasma levels of liver enzymes, lipid profiles, blood glucose, insulin and TNF-α were measured. The levels of antioxidant enzymes and lipid peroxidation were also measured along with the expression of CD36, fatty acyl-CoA synthetase (FAS), and Carnitine palmitoyl transferase I (CPT-1) beta genes in the liver.

RESULTS

The antioxidant enzymes activity significantly decreased and lipid peroxidation, lipid profiles, liver enzymes, and TNF-α significantly increased in fructose-induced metabolic syndrome compared to the control groups, as well as the level of some trace elements significantly changed (p < 0.05). Treatment with oil and safflower seed extract in a dose dependent manner could improve biochemical parameters in groups of metabolic syndrome treated with oil and extract compared to metabolic syndrome (p < 0.05). The results also showed that the expression of above mentioned genes significantly increased in groups of metabolic syndrome treated with oil and extract compared to control and metabolic syndrome groups (p < 0.05).

CONCLUSION

It can be concluded that safflower seed extract and its oil can improve fructose-induced metabolic syndrome through antioxidant and anti-inflammatory effects, adjustment of homeostasis of trace elements, and enhancing the beta-oxidation capacity of the liver by increasing the expression of CD36, FAS, and CPT-1beta genes.

Protective Effects of Serotonin and its Derivatives, N-Feruloylserotonin and N-(p-Coumaroyl) Serotonin, Against Cisplatin-Induced Renal Damage in Mice

This study examined whether serotonin and two of its derivatives, [Formula: see text]-feruloylserotonin and [Formula: see text]-([Formula: see text]-coumaroyl) serotonin, have a renoprotective effect in a mouse model of cisplatin-induced acute renal failure. Cisplatin (20[Formula: see text]mg/kg body weight) was administered by intraperitoneal injection to male BALB/c mice that had received oral serotonin, [Formula: see text]-feruloylserotonin or [Formula: see text]-([Formula: see text]-coumaroyl) serotonin (7.5[Formula: see text]mg/kg body weight per day) during the preceding 2 days. At 3 days after the cisplatin injection, serum and renal biochemical factors, oxidative stress, inflammation and apoptosis-related protein expression were evaluated, and histological examinations were performed. Cisplatin caused reduction in body weight and an increase in kidney weight; however, [Formula: see text]-([Formula: see text]-coumaroyl) serotonin and [Formula: see text]-feruloylserotonin attenuated these effects. Moreover, the serotonin derivatives significantly decreased serum urea nitrogen and creatinine levels. They also significantly reduced the level of reactive oxygen species and upregulated the expression of glutathione peroxidase in the kidney. Furthermore, the serotonin derivatives improved the abnormal expression of mitogen-activated protein kinases activation-dependent inflammation- and apoptosis-related protein and caused less renal damage. These results provide important evidence that [Formula: see text]-([Formula: see text]-coumaroyl) serotonin and [Formula: see text]-feruloylserotonin exert a pleiotropic effect on several parameters related to oxidative stress, inflammation and apoptosis. The derivatives also have a renoprotective effect in cisplatin-treated mice; however, this effect is higher with [Formula: see text]-([Formula: see text]-coumaroyl) serotonin.

Novel perspectives on the molecular crosstalk mechanisms of serotonin and melatonin in plants

Current review focuses on the significant role of serotonin and melatonin in various molecular crosstalk mechanisms in plants. In this context phytohormones (like auxin, gibberellins, ethylene or abscisic acid), plant growth regulators, and associated biomolecules like reactive oxygen species, nitric oxide, brassinosteroids and hydrogen sulphide have been discussed in a wider context. Long distance signaling responses of serotonin in association with auxin, jasmonic acid, salicylic acid and ABA have been critically reviewed. Auxin-serotonin crosstalk in relation to PIN protein functioning and root growth regulation appears to be a major advancement in the context of phytoserotonin signaling in plants. Auxin and serotonin share structural similarities which bring possibilities of auxin receptors being surrogated for serotonin transport in plants. The modulation of root apex architecture is highly regulative in terms of serotonin-jasmonic acid crosstalk. Reactive oxygen species (ROS) appears to be a primary mediator of serotonin mediated root growth response. Serotonin induced signaling therefore involve ROS, auxin, JA and ethylene action. Although there exists handful of critical reviews on the role of phytomelatonin in plants, recent advancements on its regulatory role in modulating plant hormones, ROS scavenging enzymes, ROS/RNS and glutathione levels need attention. Melatonin signaling associated with nitrogen metabolism and nitrosative stress are recent developments in plants. Interesting relationship between nitric oxide and melatonin has been established in relation with biotic and abiotic stress tolerance in plants. Developments in hydrogen sulphide-melatonin signaling in plants are still at its nascent stage but exhibits promising scopes for future.

Rare Hybrid Dimers with Anti-Acetylcholinesterase Activities from a Safflower (Carthamus tinctorius L.) Seed Oil Cake

Safflower (Carthamus tinctorius) is commercially cultivated for vegetable oil extracted from the seeds. However, during the production process of seed oil, a large amount of the oil cake is thrown away or fermented as fertilizer to improve the homing rate of pigeons. Therefore, to solve the ecological problem and develop its new function, we investigated the chemical constituents of a safflower seed oil cake, and six new hybrid dimers, (±)-carthatins A-F (1-6, respectively), with a phenylpropanoid and a feruloylserotonin fused via a dihydrofuran ring, together with four known compounds, including sinapyl alcohol (7), coniferyl alcohol (8), serotobenine (9), and feruloylserotonin (10), were isolated. The extensive nuclear magnetic resonance spectra, combined with electronic circular dichroism analysis and chiral high-performance liquid chromatography, allowed the complete structural assignments of (±)-carthatins A-F. Moreover, we evaluated their anti-acetylcholinesterase activities. Racemic carthatins A and B (1 and 2, respectively) showed anti-acetylcholinesterase effects with IC₅₀ values of 17.96 and 66.83 μM, respectively. To some extent, our findings provide a new scaffold of acetylcholinesterase inhibitors, which could be beneficial for developing therapeutic molecules for the treatment of Alzheimer's disease and supporting folk application of a safflower seed oil cake.

N-(p-coumaroyl) serotonin inhibits glioblastoma cells growth through triggering S-phase arrest and apoptosis

Glioblastoma is the most common and most malignant primary brain tumor with a median survival of 15 months. N-(p-coumaroyl) serotonin (CS) is an indole alkaloid with antioxidant, cardioprotective effects after ischemia and antitumor activity. In the present study we sought to determine whether could exert cytotoxic and cytostatic effects in glioma cells in vitro. CS was tested for toxicity in zebrafish. We investigated the effect of CS in U251MG and T98G glioblastoma cell lines. Viability and proliferation of the cells were examined with trypan blue exclusion assay and the xCELLigence system. Cell cycle, activation of caspase-8, mitochondrial membrane potential and CD24/CD44/CD56/CD15/CD71 expression were tested with flow cytometry. Treatment with CS significantly reduced cell viability in both cell lines tested. Induction of cell death and cell cycle arrest at G2/M and S-phase was confirmed with flow cytometry in both cell lines. CS produced significant higher activity of caspase-8 compared to control. After treatment with CS there was a dose-dependent increase in CD15 and CD71 expression, whereas there was no change in CD24/CD44/CD56 expression in both cell lines. The zebrafish mortality on the fifth post fertilization day was zero for even 1 mM of CS concentration. The treatment of glioblastoma cell lines with CS may represent a novel strategy for targeting glioblastoma. Further studies are obviously needed to elucidate the complete mechanism of its antitumor activity.

Mixed seeds juice with high antioxidant capacity and digestive enzyme activity and its application

To investigate the synergistic and combined effects of a seed-vegetable combination, oilseed crops (safflower seed, evening primrose seed, and sesame seed) and cereals (whole buckwheat grain) were extracted with carrot using a low-speed juice extractor. Nutrient composition showed that the mixed seeds juice provided a well-balanced diet to supplement nutrient deficiency. Four assays of antioxidant activities showed that all seed juices exhibited higher activities than carrot juice. Similarly, mixed seeds juice displayed the highest α-amylase and protease activities, implicating the formulation in the improvement of the relatively low digestibility of seed. These results indicated that juice extraction significantly (p<0.001) influenced the nutrient contents, antioxidant activities, and digestion enzyme activities of seed juice. The synergistic and combined interactions of seeds and vegetables may be beneficial in enhancing biological functions and result in a well-balanced diet.

Phytochemistry and Pharmacology of Carthamus tinctorius L

Carthamus tinctorius L. is a multifunctional cash crop. Its flowers and seeds are extensively used in traditional herbal medicine in China, Korea, Japan, and other Asian countries, for treating various ailments such as gynecological, cardiovascular, and cerebrovascular diseases as well as blood stasis and osteoporosis. More than 100 compounds have been isolated and identified from C. tinctorius. Flavonoids and alkaloids, especially the quinochalcone c-glycoside hydroxysafflor yellow A, N-(p-Coumaroyl)serotonin, and N-feruloylserotonin, are responsible for most of the pharmacological activities of C. tinctorius. In this paper, comprehensive and up-to-date information on the phytochemistry and pharmacology of C. tinctorius is presented. This information will be helpful for further explorations of the therapeutic potential of C. tinctorius and may provide future research opportunities.

Regulatory roles of serotonin and melatonin in abiotic stress tolerance in plants

Understanding the physiological and biochemical basis of abiotic stress tolerance in plants has always been one of the major aspects of research aiming to enhance plant productivity in arid and semi-arid cultivated lands all over the world. Growth of stress-tolerant transgenic crops and associated agricultural benefits through increased productivity, and related ethical issues, are also the major concerns of current research in various laboratories. Interesting data on the regulation of abiotic stress tolerance in plants by serotonin and melatonin has accumulated in the recent past. These two indoleamines possess antioxidative and growth-inducing properties, thus proving beneficial for stress acclimatization. Present review shall focus on the modes of serotonin and melatonin-induced regulation of abiotic stress tolerance in plants. Complex molecular interactions of serotonin and auxin-responsive genes have suggested their antagonistic nature. Data from genomic and metabolomic analyses of melatonin-induced abiotic stress signaling have lead to an understanding of the regulation of stress tolerance through the modulation of transcription factors, enzymes and various signaling molecules. Melatonin, nitric oxide (NO) and calmodulin interactions have provided new avenues for research on the molecular aspects of stress physiology in plants. Investigations on the characterization of receptors associated with serotonin and melatonin responses, are yet to be undertaken in plants. Patenting of biotechnological inventions pertaining to serotonin and melatonin formulations (through soil application or foliar spray) are expected to be some of the possible ways to regulate abiotic stress tolerance in plants. The present review, thus, summarizes the regulatory roles of serotonin and melatonin in modulating the signaling events accompanying abiotic stress in plants.

Towards a better understanding of medicinal uses of Carthamus tinctorius L. in traditional Chinese medicine: a phytochemical and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Carthamus tinctorius L. (Compositae), a widely used traditional Chinese medicine, was known as Hong hua (Chinese: ), safflower. Safflower with a wide spectrum of pharmacological effects has been used to treat dysmenorrhea, amenorrhea, postpartum abdominal pain and mass, trauma and pain of joints, etc. The present paper reviews the advancements in investigation of botany and ethnopharmacology, phytochemistry, pharmacology and toxicology of safflower. Finally, the possible tendency and perspective for future investigation of this plant are discussed, too.

MATERIALS AND METHODS

The information on safflower was collected via piles of resources including classic books about Chinese herbal medicine, and scientific databases including Pubmed, Google Scholar, ACS, Web of science, CNKI and others.

RESULTS

Over 104 compounds from this plant have been isolated and identified, and quinochalcones and flavonoids are considered as the characteristic and active constituents of safflower. Safflower with its active compounds possesses wide-reaching biological activities, including dilating coronary artery, improving myocardial ischemia, modulating immune system, anticoagulation and antithrombosis, antioxidation, antiaging, antihypoxia, antifatigue, antiinflammation, anti-hepatic fibrosis, antitumor, analgesia, etc.

CONCLUSIONS

As an important traditional Chinese medicine, it is important to investigate the pharmacological effects and molecular mechanisms of this plant based on modern realization of diseases' pathophysiology. More bioactive components should be identified using bioactivity-guided isolation strategies, and the possible mechanism of action as well as potential synergistic or antagonistic effects of multi-component mixtures derived from safflower need to be evaluated integrating pharmacological, pharmacokinetic, bioavailability-centered and physiological approaches. Further studies on safflower can lead to the development of new drugs and therapeutics for various diseases, and how to utilize it better should be paid more attention to.

Preferential involvement of Na⁺/Ca²⁺ exchanger type-1 in the brain damage caused by transient focal cerebral ischemia in mice

The Na(+)/Ca(2+) exchanger (NCX), an ion-transporter located in the plasma membrane of neuronal cells, contributes to intracellular Ca(2+) homeostasis. Within the brain, three isoforms (NCX1, NCX2, and NCX3) are widely distributed. However, it is not clear to what extent these isoforms are involved in ischemic brain damage in mammals. We therefore used genetically altered mice and isoform-selective NCX inhibitors in a model of transient focal ischemia to investigate the role of each NCX isoform in ischemic brain damage. NCX isoform-mutant mice (NCX1(+/-), NCX2(+/-), and NCX3(+/-)) and wild-type mice were subjected to 90min of middle cerebral artery occlusion (MCAO) followed by 24h of reperfusion. One of three NCX inhibitors [SN-6, KB-R7943, or SEA0400 (3 or 10mgkg(-1), i.p.)] was administered to ddY mice at 30min before more prolonged (4-h) MCAO followed by 24h of reperfusion. After transient MCAO reperfusion, the cerebral infarcts in NCX1(+/-) mice, but not those in NCX2(+/-) or NCX3(+/-) mice, were significantly smaller than those in wild-type mice. SN-6 and SEA0400, which are more selective for the NCX1 isoform, significantly reduced the infarct volume at 10mg/kg. In contrast, KB-R7943, which is more selective for NCX3, did not. These results suggest that the NCX1 isoform may act preferentially (vs. the NCX2 and NCX3 isoforms) to exacerbate the cerebral damage caused by ischemic insult in mice, and that NCX1-selective inhibitors warrant investigation as a potential therapeutic agents for stroke.

Protective effects of cyclo(L-Leu-L-Tyr) against postischemic myocardial dysfunction in guinea-pig hearts

The protective effects of cyclic dipeptides in alcoholic beverages were investigated in the perfused guinea-pig hearts subjected to ischemia and reperfusion. Subsequently, in order to determine the importance of cyclic dipeptide structure, the effects of cyclo(L-Leu-L-Tyr) (cLY) were compared with those of the newly synthesized non-cyclic dipeptides, L-Leu-L-Tyr (LY) and L-Tyr-L-Leu (YL). After reperfusion, pressure recovery (%) in the left ventricle reached a peak of over 90% in the presence of cLY (10(-6) M and 10(-5) M) (control: 22.9%). The recovery by LY and YL was significantly lower than that by cLY, and ATP levels simultaneously monitored using (31)P-NMR were already lower during the ischemic end period than those observed with cLY treatment. In perfused mitochondrial preparations, cLY significantly inhibited mitochondrial Ca(2+) ([Ca(2+)](m)) elevation in a similar way to that of the mitochondrial permeability transition pore (MPTP) inhibitor cyclosporin A. In vitro electron paramagnetic resonance (EPR) revealed that the active oxygen radicals quenching activity of cLY was greater than those of non-cyclic dipeptides. cLY inhibited caspase-3-induced apoptosis. The cyclic dipeptide structure inhibits opening of the MPTP by preventing [Ca(2+)](m) overload-induced apoptosis related to mitochondrial active oxygen radical accumulation in ischemia-reperfusion hearts.

Potent α-glucosidase inhibitors from safflower (Carthamus tinctorius L.) seed

As part of the search for naturally derived α-glucosidase inhibitors, the chemical components isolated from safflower seed (Carthamus tinctorius L.) were evaluated. The compounds active as α-glucosidase inhibitors were serotonin derivatives (e.g. N-p-coumaroyl serotonin (1) and N-feruloyl serotonin (2)). These compounds showed a potent inhibitory activity, the 50% inhibitory concentration (IC(50) ) values were calculated as 47.2 µm (1) and 99.8 µm (2) while that of the reference drugs acarbose and 1-deoxynojirimycin were evaluated as 907.5 µm and 278.0 µm, respectively. Regarding the structure of the serotonin derivative, the existence of the hydroxyl group at 5-position in the serotonin moiety and the linkage of cinnamic acid and serotonin are essential for α-glucosidase inhibitory activities. These results are helpful for the proper use of safflower seed as traditional medicine for the treatment of diabetes, moreover, it could serve to develop medicinal preparations as supplements and functional foods for diabetes. In particular, the serotonin compounds could be used as a lead compound for a new potential α-glucosidase inhibitor derived from the plant.

Phytoserotonin: a review

Serotonin (5-hydroxytryptamine; SER) is one of the well-studied indoleamine neurotransmitter in vertebrates. Recently SER has also been reported in wide range of plant species. The precise function of SER at the physiological level, particularly growth regulation, flowering, xylem sap exudation, ion permeability and plant morphogenesis in plant system has not been clear. Though SER is found in different parts of plant species including leaves, stems, roots, fruits and seeds, the quantity of SER within plant tissues varies widely. SER has been recently shown as a plant hormone in view of its auxin-like activity. This brief review provide an overview of SER biosynthesis, localization, its role in plant morphogenesis and possible physiological functions in plants. This would certainly help to elucidate further the multiple roles of SER in plant morphogenesis. In the future it may form the basis for studies on involvement of SER in cellular signaling mechanisms in plants. Apart from these gaps in understanding the role of SER in ontogeny of plant physiology and ecological, adaptations have been emphasized. Thus, overall perspectives in this area of research and its possible implications have been presented.

Carthamus tinctorius Enhances the Antitumor Activity of Dendritic Cell Vaccines via Polarization toward Th1 Cytokines and Increase of Cytotoxic T Lymphocytes

Carthamus tinctorius (CT), also named safflower, is a traditional Chinese medicine widely used to improve blood circulation. CT also has been studied for its antitumor activity in certain cancers. To investigate the effects of CT on the dendritic cell (DC)-based vaccine in cancer treatment, cytokine secretion of mouse splenic T lymphocytes and the maturation of DCs in response to CT were analyzed. To assess the antitumor activity of CT extract on mouse CD117⁺ (c-kit)-derived DCs pulsed with JC mammal tumor antigens, the JC tumor was challenged by the CT-treated DC vaccine in vivo. CT stimulated IFN-γ and IL-10 secretion of splenic T lymphocytes and enhanced the maturation of DCs by enhancing immunological molecule expression. When DC vaccine was pulsed with tumor antigens along with CT extract, the levels of TNF-α and IL-1β were dramatically increased with a dose-dependent response and more immunologic and co-stimulatory molecules were expressed on the DC surface. In addition, CT-treated tumor lysate-pulsed DC vaccine reduced the tumor weight in tumor-bearing mice by 15.3% more than tumor lysate-pulsed DC vaccine without CT treatment. CT polarized cytokine secretion toward the Th1 pathway and also increased the population of cytotoxic T lymphocytes ex vivo. In conclusion, CT activates DCs might promote the recognition of antigens and facilitate antigen presentation to Th1 immune responses.

Effects of Flos carthami on CYP2D6 and on the Pharmacokinetics of Metoprolol in Rats

Flos carthami is a traditional Chinese herbal medicine. Clinically, the Flos carthami Injection has been used concomitantly with other Western drugs and may be used concomitantly with β-blockers, such as metoprolol, to treat cerebrovascular and coronary heart diseases, in China. Metoprolol is a CYP2D6 substrate and is predominantly metabolized by this isozyme. However, we do not know whether there is an effect of Flos carthami on CYP2D6 and the consequences of such an effect. Concern is raised regarding the possible herb-drug interaction. In this report, the effects of Flos carthami on the activity of CYP2D6 in vivo and in vitro and on the pharmacokinetics of metoprolol, in rats, are investigated. To assess the inhibitory potency of Flos carthami, the concentration associated with 50% inhibition (IC₅₀) of dextromethorphan metabolism was determined based on the concentration-inhibition curves. The inhibitory effect of Flos carthami on CYP2D6 was also compared with cimetidine in vitro. Flos carthami could significantly inhibit CYP2D6 in rats both in vitro and in vivo (P < .05) and could slow down the metabolic rate of metoprolol as suggested by prolonged t_1/2 (67.45%), by increased C_max (74.51%) and AUC_0−∞ (76.89%). These results suggest that CYP2D6 is a risk factor when Flos carthami is administered concomitantly with metoprolol or other CYP2D6 substrates.

Effects of safflower seed extract on arterial stiffness

Safflower seed extract (SSE) contains characteristic polyphenols and serotonin derivatives (N-( p-coumaroyl) serotonin and N-feruloylserotonin), which are reported to inhibit oxidation of low-density lipoprotein (LDL), formation of atherosclerotic plaques, and improve arterial stiffness as assessed by pulse wave analysis in animal models. The effects of long-term supplementation with SSE on arterial stiffness in human subjects were evaluated. This doubleblind, placebo-controlled study was conducted in 77 males (35–65 years) and 15 postmenopausal females (55–65 years) with high-normal blood pressure or mild hypertension who were not undergoing treatment. Subjects received SSE (70 mg/day as serotonin derivatives) or placebo for 12 weeks, and pulse wave measurements, ie, second derivative of photoplethysmogram (SDPTG), augmentation index, and brachial-ankle pulse wave velocity (baPWV) were conducted at baseline, and at weeks 4, 8, and 12. Vascular age estimated by SDPTG aging index improved in the SSE-supplemented group when compared with the placebo group at four (P = 0.0368) and 12 weeks (P = 0.0927). The trend of augmentation index reduction (P = 0.072 versus baseline) was observed in the SSE-supplemented group, but reduction of baPWV by SSE supplementation was not observed. The SSE-supplemented group also showed a trend towards a lower malondialdehyde-modified-LDL autoantibody titer at 12 weeks from baseline. These results suggest long-term ingestion of SSE in humans could help to improve arterial stiffness.

Retrospect and prospect of active principles from Chinese herbs in the treatment of dementia

With an ageing population, dementia has become one of the world's primary health challenges. However, existing remedies offer limited benefits with certain side effects, which has prompted researchers to seek complementary and alternative therapies. China has long been known for abundant usage of various herbs. Some of these herbal decoctions are effective in stimulating blood circulation, supplementing vital energy and resisting aging, the lack of which are believed to underlie dementia. These herbs are regarded as new and promising sources of potential anti-dementia drugs. With the rapid evolution of life science and technology, numerous active components have been identified that are highly potent and multi-targeted with low toxicity, and therefore meet the requirements for dementia therapy. This review updates the research progress of Chinese herbs in the treatment of dementia, focusing on their effective principles.

Safflower extracts functionally regulate monoamine transporters

Safflower (HH), the dry flower of Carthamus tinctorius L., has long been used to empirically treat neuropsychological disorders such as stroke and major depression in traditional Chinese medicine, and recently been proven effective for regulating levels of dopamine and serotonin in new-born rat brain. The present study assessed whether HH would be bioactive for functionally regulating monoamine transporters using in vitro drug-screening cell lines. Our current results showed that all solvent-extracted HH fractions, in different degrees, markedly increased both dopamine uptake by Chinese hamster ovary (CHO) cells stably expressing dopamine transporter (DAT) and norepinephrine uptake by CHO cells expressing norepinephrine transporter (NET), and also showed that chloroform (HC), ethyl acetate (HE), and n-butyl alcohol extract strikingly depressed serotonin uptake by CHO cells expressing serotonin transporter (SERT); wherein, the potencies of ethanol extract, HC, HE, and aqueous extract to up-regulate dopamine/norepinephrine uptake and potency of HE to inhibit serotonin uptake were relatively stronger. Further investigation revealed that the enhancement of dopamine/norepinephrine uptake by HC and HE was dependent of DAT/NET activity, and the HE-induced inhibition of serotonin uptake was typical of competition. Thus, HH extracts are novel monoamine transporter modulators functioning as DAT/NET activators and/or SERT inhibitors, and would likely improve neuropsychological disorders through regulating monoamine-transporter activity.

Effects of safflower seed extract supplementation on oxidation and cardiovascular risk markers in healthy human volunteers

We previously demonstrated that safflower seed extract (SSE) and its major antioxidant constituents, serotonin hydroxycinnamic acid amides, suppressed LDL oxidation in vitro, decreased plasma autoantibody titres to oxidized LDL and attenuated atherosclerotic lesion formation in apoE-deficient mice. In this report, we examined whether SSE, rich in serotonin derivatives, could affect markers of oxidative stress, inflammation and aortic stiffness in healthy human subjects. Twenty Japanese male volunteers were studied at baseline, after 2.1 g SSE supplementation daily (providing 290 mg serotonin derivatives/d) for 4 weeks, and after a 4-week washout period. Significant reductions in circulating oxidized LDL, autoantibody titres to malondialdehyde-modified LDL, the soluble form of vascular cell adhesion molecule-1 (sVCAM-1), and urinary 8-isoprostane were observed after a 4-week intervention. Although there were no statistically significant differences in blood pressure or brachial-ankle pulse wave velocity (baPWV), an index of arterial stiffness, baPWV was lower than baseline in eleven of twenty subjects and was accompanied by a reduction in blood pressure. Statistically significant negative correlations were observed between the extent of initial cardiovascular risk markers (autoantibody titres, 8-isoprostane, sVCAM-1 and baPWV) and the effect of intervention. This suggested that individuals with elevated oxidative stress, inflammation, and/or arterial stiffness may receive more benefit from SSE supplementation.

Protective effects of Nicotiflorin on reducing memory dysfunction, energy metabolism failure and oxidative stress in multi-infarct dementia model rats

The present study aimed to determine whether Nicotiflorin, a natural flavonoid extracted from coronal of Carthamus tinctorius, has a protective effect on cerebral multi-infarct dementia in rats. The multi-infarct dementia model rats were prepared by injecting man-made micro-thrombi into the right hemisphere. The administration groups were treated once daily with 30, 60 and 120 mg/kg Nicotiflorin (i.g.) from 5 days before ischemia operation to 3 days after the operation for biochemical examination, 10 days for Morris water maze study and morphological observations and 20 days for eight-arm radial maze task. 2,3,5-triphenyltetrazolium chloride (TTC) staining showed that infarct volume of each Nicotiflorin administration group was much smaller than that of vehicle-treated multi-infarct dementia group, and hematoxylin and eosin (HE) staining showed that histopathological abnormalities of each Nicotiflorin group were also much lighter than that of vehicle-treated multi-infarct dementia group. Each Nicotiflorin group showed much better spatial memory performance in Morris water maze tests and eight-arm radial maze task compared with the vehicle-treated multi-infarct dementia group, significantly attenuated the elevation of lactic acid and malondialdehyde (MDA) contents and the decrease in lactate dehydrogenase (LDH), Na(+)K(+)ATPase, Ca(2+)Mg(2+)ATPase and superoxide dismutase (SOD) activity in the brain tissue which was composed of striatum, cortex and hippocampus of the ischemia hemisphere at day 3 after ischemia operation. These results suggest that Nicotiflorin has protective effects on reducing memory dysfunction, energy metabolism failure and oxidative stress in multi-infarct dementia model rats.

Protective effects of EGCg or GCg, a green tea catechin epimer, against postischemic myocardial dysfunction in guinea-pig hearts

The protective effects of (-)-epigallocatechin-3-gallate (EGCg) or the C-2 epimer, (-)-gallocatechin-3-gallate (GCg), afforded by their antioxidative activity among green tea catechins were investigated in perfused guinea-pig Langendorff hearts subjected to ischemia and reperfusion. The recovery (%) of the left ventricular developed pressure from ischemia by reperfusion was 34.4% in the control, while in the presence of EGCg (3x10(-5) M) or GCg (3x10(-6) M, a more diluted concentration than that of EGCg), it led to a maximal increase of 78.4% or 76.2%, consistent with a significant preservative effect on the tissue level of ATP at the end of ischemia or reperfusion. In the perfused preparation of mitochondria, EGCg (10(-5) M) inhibited mitochondrial Ca(2+) elevation by changes in the Ca(2+) content or the acidification of perfusate, similarly to findings with cyclosporin A, a well known inhibitor of the mitochondrial permeability transition pore. By in vitro electron paramagnetic resonance (EPR), EGCg or GCg was found to directly quench the activity of active oxygen radicals, with the strongest activity in tea catechins. EGCg or GCg decreased the caspase-3 activity induced apoptosis. Therefore, it is concluded that the beneficial effects of EGCg or GCg play an important role in ischemia-reperfusion hearts in close relation with nitric oxide (NO), active oxygen radicals and biological redox systems in mitochondria.

Positive inotropic effect of purified green tea catechin derivative in guinea pig hearts: the measurements of cellular Ca2+ and nitric oxide release

Each individual and pure catechin isolated from green tea was investigated as to its myocardial or blood pressure effects. The nitric oxide (NO) electrode and fluorometry were used to monitor changes in the NO and Ca(2+) contents of the heart, together with simultaneous recordings of the left ventricular developed pressure. The low dose of (-)-epigallocatechin-3-gallate (EGCg: 10(-6), 10(-5 )M) increased the left ventricular developed pressure with elevation of the transient fura-2 Ca(2+) signal (T(Ca)), but the high dose of EGCg (10(-4 )M) produced a maximum left ventricular developed pressure with decreases in the basal level of T(Ca) in a manner similar to the administration of the Ca-sensitizer pimobendan. However, the level of the transient NO signal (T(NO)) increased dose-dependently without any increases in the width of T(NO). In the isolated right atria, the contractile force of (-)-gallocatechin-3-gallate (GCg) at 10(-8)-10(-4 )M produced the highest pD(2) value, 6.7, in catechins (EGCg: 5.2, pimobendan: 5.1), but did not affect the heart rate. GCg, an artifact due to the epimerization of EGCg during the heating procedure, showed the most prolonged hypotensive effect in rabbits among the catechins. Each catechin (GCg or EGCg), like the NO donor, may have a therapeutic use as an NO-mediated vasorelaxant and may have an additional protective action in myocardial ischemia-reperfusion induced injury.

Serotonin derivatives, major safflower (Carthamus tinctorius L.) seed antioxidants, inhibit low-density lipoprotein (LDL) oxidation and atherosclerosis in apolipoprotein E-deficient mice

The effects of defatted safflower seed extract and its phenolic constituents, serotonin derivatives, on atherosclerosis were studied. Ethanol-ethyl acetate extract of safflower seeds (SSE) inhibited low-density lipoprotein (LDL) oxidation induced in vitro by an azo-containing free-radical initiator V70 or copper ions. Two serotonin derivatives [N-(p-coumaroyl)serotonin, CS; N-feruloylserotonin, FS] and their glucosides were identified as the major phenolic constituents of the extract. The study with chemically synthesized materials revealed that a majority of the antioxidative activity of SSE was attributable to the aglycones of these two serotonin derivatives. Orally administered CS and FS suppressed CuSO(4)-induced plasma oxidation ex vivo. Long-term (15 week) dietary supplementation of SSE (1.0 wt %/wt) and synthetic serotonin derivatives (0.2-0.4%) significantly reduced the atherosclerotic lesion area in the aortic sinus of apolipoprotein E-deficient mice (29.2-79.7% reduction). The plasma level of both lipid peroxides and anti-oxidized LDL autoantibody titers decreased concomitantly with the reduction of lesion formation. Serotonin derivatives were detected as both intact and conjugated metabolites in the plasma of C57BL/6J mice fed on 1.0% SSE diet. These findings demonstrate that serotonin derivatives of SSE are absorbed into circulation and attenuate atherosclerotic lesion development possibly because of the inhibition of oxidized LDL formation through their strong antioxidative activity.

Cardioprotective effects of Ilex paraguariensis extract: evidence for a nitric oxide-dependent mechanism

AIM

To examine the effects of an Ilex paraguariensis (Ip) extract on postischemic alterations derived from 20 min of global ischemia and 30 min of reperfusion.

METHODS

Isolated rat hearts were treated 10 min before ischemia and the first 10 min of reperfusion with Ip 30 microg/ml. In other hearts, chelerythrine (1 microM), a protein kinase C blocker, or l(G)-nitro l-arginine methyl ester (l-NAME), a nitric oxide synthase inhibitor, were administered prior to Ip infusion. Left ventricular developed pressure (LVDP), +dP/dt(max), -dP/dt(max), and left ventricular end diastolic pressure (LVEDP) were used to assess myocardial function. Thiobarbituric acid reactive substances (TBARS) were measured.

RESULTS

Ip treatment produced an improvement of postichemic recovery (LVDP=96+/-8%; +dP/dt(max)=95+/-10%; -dP/dt(max)=90+/-12% vs. 57+/-6%, 53+/-6% and 57+/-8%, respectively, in untreated hearts) and an attenuation of the increase of LVEDP and TBARS content. Chelerythrine did not modify and l-NAME abolished the protection induced by Ip.

CONCLUSIONS

These data are the first demonstration that Ip extract attenuates the myocardial dysfunction provoked by ischemia and reperfusion and that this cardioprotection involves a diminution of oxidative damage through a nitric oxide-dependent mechanism.

Protective effects of sarpogrelate, a 5-HT2A antagonist, against postischemic myocardial dysfunction in guinea-pig hearts

The protective effects of sarpogrelate (SG), a 5-HT2A antagonist, were investigated in perfused guinea-pig Langendorff hearts subjected to ischemia and reperfusion. Changes in cellular levels of high phosphorous energy, NO and Ca2+ in the heart together with simultaneous recordings of left ventricular developed pressure (LVDP) were monitored using an nitric oxide (NO) electrode, fluorometry and 31P-NMR. The recovery of LVDP from ischemia by reperfusion was 30.1% in the control, while the treatment with SG (5 x 10(-7) M) in pre- and post-ischemia hearts produced a gradual increase to 73.1 and 53.6%, respectively. At the final stage of ischemia, the intracellular concentration of Ca2+ ([Ca2+]i) and release of NO increased with no twitching and remained at a high steady level. The addition of SG increased the transient NO signal (TNO) level at the end of ischemia compared with the control, but [Ca2+]i during ischemia decreased. Meanwhile, mitochondrial Ca2+ uptake on acidification or Ca2+ content changes of the perfusate was suppressed by pre-treatment with SG or the KATP channel opener diazoxide, but not the KATP channel blocker 5-HD. The myocardial NO elevated with 5-HT in normal Langendorff hearts was suppressed by the treatment with SG. Therefore, the existence of the 5HT2A receptor in a Langendorff heart was anticipated. By in vitro EPR, SG was found to directly quench the hydroxy radical. Thus, these findings suggested that the 5-HT2A receptor induced in ischemia-reperfusion plays an important role in the mitochondrial KATP channel of hearts in close relation with NO and active oxygen radicals.

Production of coumaroylserotonin and feruloylserotonin in transgenic rice expressing pepper hydroxycinnamoyl-coenzyme A:serotonin N-(hydroxycinnamoyl)transferase

Transgenic rice (Oryza sativa) plants were engineered to express a N-(hydroxycinnamoyl)transferase from pepper (Capsicum annuum), which has been shown to have hydroxycinnamoyl-CoA:tyramine N-(hydroxycinnamoyl)transferase activity, a key enzyme in the synthesis of hydroxycinnamic acid amides, under the control of constitutive maize (Zea mays) ubiquitin promoter. The transgenic rice plants require foliar application of amines to support synthesis of hydroxycinnamic acid amides, suggestive of limiting amine substrates in rice shoots. In addition, when T2 homozygous transgenic rice plants were grown in the presence of amines or phenolic acids, two novel compounds were exclusively identified in the leaves of the transgenic plants. These compounds eluted earlier than p-coumaroyltyramine and feruloyltyramine during HPLC chromatography and were identified as p-coumaroylserotonin and feruloylserotonin by liquid chromatography/mass spectrometry and other methods. To test whether the unpredicted production of serotonin derivatives is associated with the pepper N-(hydroxycinnamoyl)transferase, the substrate specificity of the pepper enzyme was analyzed again. Purified recombinant pepper N-(hydroxycinnamoyl)transferase exhibited a serotonin N-hydroxycinnamoyltransferase (SHT) activity, synthesized p-coumaroylserotonin and feruloylserotonin in vitro, and demonstrated a low K(m) for serotonin. SHT activity was inhibited by 10 to 50 mm tyramine. In addition, SHT activity was predominantly found in the root tissues of wild-type rice in parallel with the synthesis of serotonin derivatives, suggesting that serotonin derivatives are synthesized in the root of rice. This is the first report of SHT activity and the first demonstration, to our knowledge, that serotonin derivatives can be overproduced in vivo in transgenic rice plants that express serotonin N-(hydroxycinnamoyl)transferase.