Multiple Direct Effects of the Dietary Protoalkaloid N-Methyltyramine in Human Adipocytes.

Dietary amines have been the subject of a novel interest in nutrition since the discovery of trace amine-associated receptors (TAARs), especially TAAR-1, which recognizes tyramine, phenethylamine, tryptamine, octopamine, N-methyltyramine (NMT), synephrine, amphetamine and related derivatives. Alongside the psychostimulant properties of TAAR-1 ligands, it is their ephedrine-like action on weight loss that drives their current consumption via dietary supplements advertised for 'fat-burning' properties. Among these trace amines, tyramine has recently been described, at high doses, to exhibit an antilipolytic action and activation of glucose transport in human adipocytes, i.e., effects that are facilitating lipid storage rather than mobilization. Because of its close structural similarity to tyramine, NMT actions on human adipocytes therefore must to be reevaluated. To this aim, we studied the lipolytic and antilipolytic properties of NMT together with its interplay with insulin stimulation of glucose transport along with amine oxidase activities in adipose cells obtained from women undergoing abdominal surgery. NMT activated 2-deoxyglucose uptake when incubated with freshly isolated adipocytes at 0.01-1 mM, reaching one-third of the maximal stimulation by insulin. However, when combined with insulin, NMT limited by half the action of the lipogenic hormone on glucose transport. The NMT-induced stimulation of hexose uptake was sensitive to inhibitors of monoamine oxidases (MAO) and of semicarbazide-sensitive amine oxidase (SSAO), as was the case for tyramine and benzylamine. All three amines inhibited isoprenaline-induced lipolysis to a greater extent than insulin, while they were poorly lipolytic on their own. All three amines-but not isoprenaline-interacted with MAO or SSAO. Due to these multiple effects on human adipocytes, NMT cannot be considered as a direct lipolytic agent, potentially able to improve lipid mobilization and fat oxidation in consumers of NMT-containing dietary supplements.

A composite device for viscosupplementation treatment resistant to degradation by reactive oxygen species and hyaluronidase.

Osteoarthritis (OA) is one of the most common musculoskeletal disorders in the world. OA is often associated with the loss of viscoelastic and tribological properties of synovial fluid (SF) due to degradation of hyaluronic acid (HA) by reactive oxygen species (ROS) and hyaluronidases. Viscosupplementation is one of the ways how to effectively restore SF functions. However, current viscosupplementation products provide only temporal therapeutic effect because of short biological half-life. In this article we describe a novel device for viscosupplementation (NV) based on the cross-linked tyramine derivative of HA, chondroitin sulfate (CS), and high molecular weight HA by online determination of viscoelastic properties loss during degradation by ROS and hyaluronidase. Rheological and tribological properties of developed viscosupplement were compared with HA solutions with different molecular weights in the range 500-2000 kDa, which are currently commonly used as medical devices for viscosupplementation treatment. Moreover, based on clinical practice and scientific literature all samples were also diluted by model OA SF in the ratio 1:1 (vol/vol) to better predict final properties after injection to the joint. The observed results confirmed that NV exhibits appropriate rheological properties (viscosity, elastic, and viscous moduli) comparable with healthy SF and maintain them during degradation for a significantly longer time than HA solutions with molecular weight in the range 500-2000 kDa and cross-linked material without CS.

Calcium peroxide aids tyramine-alginate gel to crosslink with tyrosinase for efficient cartilage repair.

The innate cartilage extracellular matrix is avascular and plays a vital role in innate chondrocytes. Recapping the crucial components of the extracellular matrix in engineered organs via polymeric gels and bioinspired approaches is promising for improving the regenerative aptitude of encapsulated cartilage/chondrocytes. Conventional gel formation techniques for polymeric materials rely on employing oxidative crosslinking, which is constrained in this avascular environment. Further, poor mechanical properties limit the practical applications of polymeric gels and reduce their therapeutic efficacy. Herein, the purpose of this study was to develop a bioadhesive gel possessing dual crosslinking for engineering cartilage. Tyramine (TYR) was first chemically conjugated to the alginate (ALG) backbone to form an ALG-TYR precursor, followed by the addition of calcium peroxide (CaO2); calcium ions of CaO2 physically crosslink with ALG, and oxygen atoms of CaO2 chemically crosslink TYR with tyrosinase, thus enabling dual/enhanced crosslinking and possessing injectability. The ALG-TYR/tyrosinase/CaO2 gel system was chemically, mechanically, cellularly, and microscopically characterized. The gel system developed herein was biocompatible and showed augmented mechanical strength. The results showed, for the first time, that CaO2 supplementation preserved cell viability and enhanced the crosslinking ability, bioadhesion, mechanical strength, chondrogenesis, and stability for cartilage regeneration.

Quantification of hordenine in a complex plant matrix by direct analysis in real time-high-resolution mass spectrometry: Application to the "plant of concern" Sceletium tortuosum.

Recently, there has been an increase in the recreational abuse of several psychoactive plants, resulting in the United Nations Office on Drugs and Crime creating a list of "plants of concern." One such material is Sceletium tortuosum and products derived from it. Regulation of these materials is challenging because of their innocuous appearance, the cumbersome sample preparation steps required to render the material into a form amenable to analysis by conventional techniques, the requirement for nuanced sample analysis protocols, and lengthy analysis times. It is demonstrated here that direct analysis in real time-high-resolution mass spectrometry (DART-HRMS) can be used to not only identify S. tortuosum material based on the detection of characteristic biomarkers including hordenine and several mesembrine alkaloids, but also quantify the amount of hordenine present. Using hordenine-d6 as an internal standard, a protocol, validated according to US Food and Drug Administration (FDA) Guidelines for the Development and Validation of Bioanalytical Methods, was devised for the quantification of the psychoactive component hordenine. The method was then applied to the quantification of hordenine in six commercially available products derived from the foliage and stems of S. tortuosum. By this method, the lower limit of quantification (LLOQ) was found to be 1 µg/ml. Observed hordenine concentrations ranged from 0.02738 to 1.071 mg of hordenine per gram of plant material. The developed technique provides an effective and quick means for the detection and quantification of hordenine in S. tortuosum, which can be extended to analysis of other hordenine-containing products.

Interfacially Super-Assembled Tyramine-Modified Mesoporous Silica-Alumina Oxide Heterochannels for Label-Free Tyrosinase Detection.

Tyrosinase (TYR) is a multifunctional copper-containing enzyme that plays a critical role in the biosynthetic pathway of melanin. Thus, the detection of TYR activity possesses vast importance from clinical diagnosis to the food industry. However, most TYR detection methods are expensive, complicated, and time-consuming. Herein, a functional nanofluidic heterochannel composed of an ultrathin tyramine-modified mesoporous silica layer (Tyr-MS) and alumina oxide (AAO) arrays is constructed by an interfacial super-assembly method. The heterochannel with plenty of enzyme catalytic sites for TYR provides the response of the ion current signal against TYR concentrations. Introducing enzymatic reaction paves the way for the heterochannel to achieve label-free, selective, specific detection of TYR. Notably, a highly sensitive detection of TYR with a limit of 2 U mL-1 was obtained by optimizing the modified conditions. Detailed investigations and theoretical calculations further reveal the mechanism for the detection performance. This work provides a simple, low-cost, quick response, and label-free platform based on functional nanofluidic devices for enzyme-sensing technologies.

Total barley maiya alkaloids inhibit prolactin secretion by acting on dopamine D2 receptor and protein kinase A targets.

ETHNOPHARMACOLOGICAL RELEVANCE: Barley maiya from gramineous plants (Hordeum vulgare L.) is obtained from ripe fruits through germination and drying. It is often used to treat diseases associated with high prolactin levels. OBJECTIVE: To investigate the anti-hyperprolactinemia (anti-HPRL) mechanisms of total barley maiya alkaloids (TBMA) and hordenine. METHODS: This experiment included 9 groups: Normal group, TBMA group, hordenine group, TBMA + haloperidol group, TBMA + forskolin group, TBMA + 8-bromo-cAMP group, hordenine + haloperidol group, hordenine + forskolin group, and hordenine + 8-bromo-cAMP group. The prolactin (PRL) concentration in the supernatant and the total cAMP concentration in the cells were detected by ELISA. The expression levels of PRL, dopamine D2 receptor (DRD2) and cAMP/PKA/CREB protein were measured by Western Blot. RESULTS: In the TBMA group and the hordenine group, the PRL level in MMQ cells was significantly decreased, but in GH3 cells there was no change. DRD2 expression level was markedly increased, cAMP concentration was decreased, and the activity of PKA and CREB declined in MMQ cells. Compared with the TBMA group, there was a significant decrease of DRD2 expression level, a remarkable increase of PRL secretion and an increase of cAMP/PKA/CREB expression in MMQ cells within the TBMA + haloperidol group. Compared with the forskolin group, there was no significant change in PRL secretion and cAMP/PKA/CREB expression level in MMQ cells within the TBMA + forskolin group. There was a decrease in PRL secretion and cAMP/PKA/CREB expression level in MMQ cells within the TBMA + 8-bromo-cAMP group compared with the 8-bromo-cAMP group. Compared with the hordenine group, DRD2 expression level was significantly decreased, PRL secretion was markedly increased, and cAMP/PKA/CREB expression level was increased in MMQ cells within the hordenine + haloperidol group. There was no significant change in PRL secretion and cAMP/PKA/CREB expression level in MMQ cells within the hordenine + forskolin group compared with the forskolin group and within the hordenine + 8-bromo-cAMP group compared with the 8-bromo-cAMP group. CONCLUSION: TBMA and hordenine can both play an anti-HPRL role via DRD2, and TBMA can also act on PKA targets to exert its anti-HPRL effect. TBMA and hordenine may be potential treatment strategies for HPRL.

Lyciyunin, a new dimer of feruloyltyramine and five bioactive tyramines from the root of Lycium yunnanense Kuang.

Lyciyunin, a new dimer of feruloyltyramine (1), together with five known tyramines (2-6), was isolated from the water-soluble fraction of an EtOH extract of the root of L. yunnanense. Based on HR-TOF-MS, NMR spectral data and quantum chemistry ECD calculations, the structure of this new compound was determined, including its absolute configuration. Compounds (1-6) were tested for their antioxidant activity using in vitro DPPH radical scavenging assay, and 1-6 showed the moderate antioxidant activities with IC50 values of 12.44 ± 0.39, 21.29 ± 0.75, 24.44 ± 1.63, 21.15 ± 0.66, 21.15 ± 0.66 and 45.15 ± 0.56 µM, respectively. Compounds (5-6) showed anti-inflammatory activity in LPS-induced RAW 264.7 macrophages with the IC50 values of 43.95 ± 6.11 and 33.50 ± 2.04 µM, respectively.

UHPLC-DPPH method reveals antioxidant tyramine and octopamine derivatives in Celtis occidentalis.

Celtis occidentalis L. (common Hackberry, Cannabaceae) has been applied in the traditional medicine for a long time as a remedy for sore throat, aid during menstruation and for treating jaundice. Nevertheless, the phytochemical exploration of the plant is still incomplete, literature data is limited to flavonoid derivatives isolated from the leaves. The present study reports screening approaches for bioactive compounds in C. occidentalis by fast and simple UHPLC-coupled assays. The UHPLC-DPPH method revealed six constituents in the methanolic extract of the twigs that had not been reported in C. occidentalis before. The antioxidant compounds were isolated by the means of flash chromatography and semi-preparative HPLC and identified by Orbitrap® MS and NMR spectroscopy as N-trans-p-coumaroyloctopamine (1), N-trans-feruloyloctopamine (2), N-trans-caffeoyltyramine (3), 2-trans-3-(4-hydroxyphenyl)-N-[2-(4-hydroxyphenyl)-2-oxoethyl] prop-2-enamide (4), N-trans-p-coumaroyltryramine (5) and N-trans-feruloyltyramine (6). Despite the high antioxidant activity measured in the present study and literature data suggesting potential positive effects of the compounds in the central nervous system, the PAMPA-BBB assay performed with the Celtis extract revealed that none of the aforementioned compounds are able to penetrate across the blood-brain barrier via transcellular passive diffusion.

Ameliorative effect of phosphodiesterase 4 and 5 inhibitors in deoxycorticosterone acetate-salt hypertensive uni-nephrectomized KKAy mice.

Diabetic nephropathy (DN) is a leading cause of end-stage renal disease (ESRD). Hypertension increases kidney stress, which deteriorates function, and leads to peripheral renal vascular resistance. Long-term hypoperfusion promotes interstitial fibrosis and glomerular sclerosis, resulting in nephrosclerosis. Although hypertension and DN are frequent ESRD complications, relevant animal models remain unavailable. We generated a deoxycorticosterone acetate (DOCA)-salt hypertensive uni-nephrectomized (UNx) KKAy mouse model demonstrating hypertension, hyperglycemia, cardiac hypertrophy, kidney failure, increased urinary albumin creatinine ratio (UACR), and increased renal PDE4D and cardiac PDE5A mRNA levels. We hypothesized that the novel PDE4 selective inhibitor, compound A, and PDE5 inhibitor, sildenafil, exhibit nephroprotective, and cardioprotective effects in this new model. Compound A, sildenafil, and the angiotensin II receptor blocker, irbesartan, significantly reduced ventricular hypertrophy and pleural effusion volume. Meanwhile, compound A and sildenafil significantly suppressed the UACR, urinary kidney injury molecule-1, and monocyte chemoattractant protein-1 levels, as well as that of renal pro-fibrotic marker mRNAs, including collagen 1A1, fibronectin, and transforming growth factor-beta (TGF-ß). Moreover, compound A significantly suppressed TGF-ß-induced pro-fibrotic mRNA expression in vitro in all major kidney lesions, including within the glomerular mesangial region, podocytes, and epithelial region. Hence, PDE4 and PDE5 inhibitors may be promising treatments, in combination with irbesartan, for DN with hypertension as they demonstrate complementary mechanisms.

In Search of a Phosphorus Dendrimer-Based Carrier of Rose Bengal: Tyramine Linker Limits Fluorescent and Phototoxic Properties of a Photosensitizer.

Photodynamic therapy (PDT) is a skin cancer treatment alternative to chemotherapy and radiotherapy. This method exploits three elements: a phototoxic compound (photosensitizer), light source and oxygen. Upon irradiation by light of a specific wavelength, the photosensitizer generates reactive oxygen species triggering the cascade of reactions leading to cell death. The positive therapeutic effect of PDT may be limited due to low solubility, low tumor specificity and inefficient cellular uptake of photosensitizers. A promising approach to overcome these obstacles involves the use of nanocarrier systems. The aim of this initial study was to determine the potential of the application of phosphorus dendrimers as carriers of a photosensitizer-rose bengal (RB). The primary goal involved the synthesis and in vitro studies of covalent drug-dendrimer conjugates. Our approach allowed us to obtain RB-dendrimer conjugates with the use of tyramine as an aromatic linker between the carrier and the drug. The compounds were characterized by FT-IR, 1H NMR, 13C NMR, 31P NMR, size and zeta potential measurements and spectrofluorimetric analysis. The dialysis to check the drug release from the conjugate, flow cytometry to specify intracellular uptake, and singlet oxygen generation assay were also applied. Finally, we used MTT assay to determine the biological activity of the tested compounds. The results of our experiments indicate that the conjugation of RB to phosphorus dendrimers via the tyramine linker decreases photodynamic activity of RB.

Bioactivities of 7'­ethoxy­trans­feruloyltyramine from Portulaca oleracea L. and its metabolism in rats using ultra­high­performance liquid chromatography electrospray coupled with quadrupole time­of­flight mass spectrometry.

This research aims to study the antioxidation and anticholinesterase activities of 7'-ethoxy-trans-feruloyltyramine (ETFT), which was an alkaloid isolated from Portulaca oleracea for the first time. Furthermore, its main metabolites and metabolic pathways in rats were also explored. The antioxidation and anticholinesterase effects of ETFT were, respectively, examined using 1,1-diphenyl-2-picrylhydrazyl assay and modified Ellman's method. The results showed that ETFT exhibited both the good antioxidant and anticholinesterase effects. Its main metabolites in rats were implemented, and nine metabolites were finally found in the rat's plasma and urine, including the oxidation, reduction, hydrolysis, glucuronidation, sulfation, and glutathionylation process.

Cerebral MAO Activity Is Not Altered by a Novel Herbal Antidepressant Treatment.

Inhibition of monoamine oxidase (MAO)-A/B can ameliorate depressive- and anxiety-related symptoms via increase of monoamine extracellular levels. However, such inhibition can also instigate hypertensive response following exposure to dietary tyramine (i.e., "the cheese effect"). Novel herbal treatment (NHT) is an herbal formula that has been demonstrated to reduce depressive- and anxiety-like symptoms in pre-clinical studies. The aim of the current study was to examine whether the therapeutic potential of NHT is underlain by inhibition of MAO-A/B and whether NHT poses a risk for tyramine hyper-potentiation. Unpredictable chronic mild stress (UCMS)-exposed mice and naïve mice were treated for 3 weeks with NHT (30 mg/kg; i.p.), the selective serotonin reuptake inhibitor (SSRI) escitalopram (15 mg/kg; i.p.), or saline. Subsequently, MAO-A/B activities in the hypothalamus, striatum, and prefrontal cortex (PFC) were assessed. Exposure to UCMS led to significant increases in both MAO-A and MAO-B activities in the hypothalamus (p < 0.001) and in the PFC (p < 0.01 for MAO-A; p < 0.001 for MAO-B). Neither NHT nor escitalopram had any notable effects. Treatment with NHT was supported as safe in terms of risk for inducing a hypertensive response. The antidepressant- and anxiolytic-like effects of NHT are mediated via pathways other than MAO-A/B inhibition.

Differential mechanisms of action of the trace amines octopamine, synephrine and tyramine on the porcine coronary and mesenteric artery.

Trace amines such as p-tyramine, p-octopamine and p-synephrine are found in low concentrations in animals and plants. Consumption of pre-workout supplements containing these plant-derived amines has been associated with cardiovascular side effects. The aim of this study was to determine the mechanisms of action of these trace amines on porcine isolated coronary and mesenteric arteries. Noradrenaline caused contraction of mesenteric arteries and relaxation of coronary arteries. In both tissues, all three trace amines induced contractions with similar potencies and responses were unaffected by the ß-adrenoceptor antagonist propranolol (1 µM), the nitric oxide synthase inhibitor L-NNA (100 µM), or the TAAR-1 antagonist, EPPTB (100 nM). However, the contractile responses of mesenteric arteries, but not coronary arteries, were significantly reduced by depletion of endogenous noradrenaline. Mesenteric responses to all three amines were abolished in the presence of prazosin (1 µM) whereas residual contractile responses remained in the coronary artery which were inhibited by a high concentration (100 µM) of EPPTB. The results suggest complex responses of the coronary artery to the trace amines, with activity at α1-adrenoceptors and potentially TAARs other than TAAR-1. In contrast the actions of the amines on the mesenteric artery appeared to involve indirect sympathomimetic actions and direct actions on α1-adrenoceptors.

Effects of onion or caraway on the formation of biogenic amines during sauerkraut fermentation and refrigerated storage.

The effects of onion or caraway on changes in the content of biogenic amines were examined in sauerkraut during a fermentation process at 18 °C or 31 °C for 14 days and subsequent storage at 4 °C for 12 weeks. The amines were analysed by high-performance liquid chromatography with pre-column benzoylation. Total biogenic-amine concentration at the end of the fermentation was lower at 31 °C than at 18 °C. However, at this lower temperature, the presence of caraway or onion more significantly (than at 31 °C) reduced the total biogenic-amine content as compared to the control sample without an additive. After 12 weeks of refrigerated storage, concentrations of phenethylamine, tryptamine, and tyramine in the sauerkraut fermented with caraway (and concentrations of putrescine and tryptamine in the sauerkraut fermented with onion) at 31 °C increased as compared to the samples on the last day of fermentation, but did not pose a risk for consumer health.

Effects of N-trans-feruloyltyramine isolated from laba garlic on antioxidant, cytotoxic activities and H2O2-induced oxidative damage in HepG2 and L02 cells.

Laba garlic is a kind of processed garlic products, it is the traditional Chinese food with a long history. In this study, the antitumor, antioxidant and cytotoxic properties of the blue pigment (BP) from Laba garlic were investigated. N-trans-feruloyltyramine (FLA) was isolated and identified from BP. The protective effects of FLA against H2O2-induced oxidative damages in L02 cells were also assessed. The apoptotic effects of FLA were detected by using flow cytometry analysis. Results showed that the tumor growth was significantly suppressed by BP (P<0.05). BP and FLA exhibited remarkable antioxidant activities. L02 cells pretreatment with FLA could significantly fight against the oxidative damage induced by H2O2, inhibit the morphological changes of mitochondria and maintain the integrity of mitochondria. FLA showed proliferation inhibition on HepG2 cells with IC50 value of 194 ±â€¯0.894 µM. After treatment of FLA (320 µM), the results of MTT assay on HepG2 and L02 cells indicated that FLA had selective cytotoxic effects. It suggested a new way of prevention and treatment of tumors and FLA might be a promising candidate in cancer therapy and functional foods.

Effects of the amino acid derivatives, ß-hydroxy-ß-methylbutyrate, taurine, and N-methyltyramine, on triacylglycerol breakdown in fat cells.

Various amino acid (AA) metabolites are used as supplements to facilitate metabolic control and enhance responsiveness of insulin-sensitive tissues. ß-hydroxy-ß-methylbutyrate (HMB) is a leucine metabolite proposed to prevent muscle wasting and to mitigate insulin resistance. Taurine, commonly added to energizing drinks, is a metabolite of methionine and cysteine present in bile juice, and proposed to be involved in lipid digestion and to be pro-lipolytic in adipocytes. N-methyltyramine (NMT) is a phenylalanine metabolite found in orange juices at 0.1-3 ppm while its effects on lipid mobilization remain controversial. Here, the putative lipolytic effects of these AA metabolites were studied and it was tested whether they could enhance insulin antilipolytic response in adipocytes. Release of glycerol and non-esterified fatty acids (NEFAs) was measured after a 2-h incubation of adipocytes obtained from control and diet-induced obese mice or from obese patients. In mouse, none of the tested AA derivatives was lipolytic from 1 µM to 1 mM. These compounds did not improve insulin antilipolytic effect or isoprenaline lipolytic action, except for 1 mM NMT that impaired triacylglycerol breakdown in obese mice. In human adipocytes, HMB and taurine were not lipolytic, while NMT weakly activated glycerol and NEFA release at 1 mM. However, 100 µM NMT impaired isoprenaline-stimulated lipolysis in a manner that was hardly added to insulin antilipolytic effect. Since none of these AA derivatives acutely helped or replaced insulin antilipolytic effect in adipocytes, the present in vitro observations do not support their proposed insulin-sensitizing properties. Moreover, NMT, HMB, and taurine were not notably lipolytic.

Effect of N-methyltyramine on the regulation of adrenergic receptors via enzymatic epinephrine synthesis for the treatment of gastrointestinal disorders.

BACKGROUND: Citri Reticulatae Pericarpium (CRP), Aurantii Fructus Immaturus (AFI) and Aurantii Fructus (AF) are all important Citrus species used in traditional Chinese medicines (TCMs) for the treatment of gastrointestinal disorders. Although they have been used since ancient times and are still in use today, the mechanistic basis for their regulation of adrenergic receptors (ARs) is still not clear. PURPOSE: In this study, we aimed to determine the active components and mechanisms of action of CRP, AFI and AF in treating gastrointestinal disorders related to ARs. METHODS: First, the phenethylamine alkaloid components of CRP, AFI and AF were identified and compared across 30 samples of three Citrus species by UPLC-Q/TOF-MS in combination with content difference analysis. Second, the effect of the main active alkaloid component on AR-based gastrointestinal disorders was investigated by an in vivo small intestinal propulsive test and an in vitro relaxing small intestinal smooth muscle activity test. The mechanism of AR regulation of the active alkaloid was further studied by evaluating its effect on relaxing small intestinal smooth muscle in the presence of an inhibitor. Lastly, the enzymes, which played an important role in epinephrine synthesis and AR regulation, were detected by immunohistochemistry. RESULTS: Three phenethylamine AR regulators (N-methyltyramine, synephrine and hordenine) in CRP, AFI and AF were characterized. It was found that N-methyltyramine could relax mouse small intestinal smooth muscle and inhibit small intestinal propulsion. The effect of N-methyltyramine on relaxing small intestinal smooth muscle could be inhibited by a-methyl-l-tyrosine. The enzymes related epinephrine synthesis and AR function were found in the mouse small intestine. The biotransformation process that converts N-methyltyramine to epinephrine was determined. CONCLUSION: The treatment of gastrointestinal disorders of CRP, AFI and AF is associated with their alkaloid component N-methyltyramine via the regulation of ARs, and the mechanism is considered to be the biotransformation of N-methyltyramine to epinephrine by serial synthase, which takes place at the nerves cells in small intestine.

Effect of Aurea Helianthus stem extract on anti-melanogenesis.

Aurea Helianthus (AH), also known as wild confederate rose or golden sunflower, is a curative herb. It has been used as a medicinal material in China due to its anti-inflammatory, immune regulatory, and anti-oxidant activities. However, its melanogenic effect on skin has not been sufficiently investigated. In this study, we tested whether AH has melanogenic inhibitory activities for the development of effective skin whitening agent. The extract showed inhibition of melanin synthesis and reduced the oxidation of 3, 4-dihydroxyphenilalanine (DOPA) to o-dopaquinone. Additionally, AH downregulated the levels of microphthalmia-associated transcription factor (MITF), tyrosinase and tyrosinase related proteins (TRPs), suggesting that AH has inhibitory effects on melanogenesis. Analysis of the components of AH showed that it contained paprazine and trans-N-feruloyltyramine (FA). We confirmed that the effect of AH resulted from paprazine and FA. Therefore, AH might have potential as an effective candidate for skin whitening.

Anticomplement compounds from Polygonum chinense.

Five new compounds including two phenyldilactones (1, 2), two coumarins (3, 4) and a dimer of N-E-feruloyl tyramine (5) together with twenty-three known compounds (6-28) were isolated from a medicinal plant Polygonum chinense. The structures of the new compounds were established by detailed spectral analysis. The absolute configurations of 1 and 5 were elucidated by Mosher's method, Mo2(OAc)4-induced electronic circular dichroism (ECD) data, and ECD calculation. All the compounds were found to show potent anticomplement activity with CH50 and AP50 values ranging from 0.18 to 1.45 mM, and 0.26 to 2.80 mM, respectively. Phenyldilactones and phenylpropionic tyramines were firstly reported as anticomplement agents. The targets of compounds 1, 3, 5 and 10 in complement activation cascade were identified as well.

[Phenylpropanoid amides from whole plants of Corydalis edulis].

Ten phenylpropanoid amides were isolated from the whole plants of Corydalis edulis Maxim. by various of column chromatographies including silica gel, Sephadex LH-20, and ODS. Their structures were identified on the basis of physicochemical properties, MS, NMR, and IR spectroscopic data. These compounds were identified as N-trans-sinapoyl-3-methoxytyramine-4'-O-ß-glucoside(1), N-trans-sinapoyl-3-methoxytyramine(2), N-trans-sinapoyltyramine(3), N-trans-p-coumaroyltyramine(4), N-trans-sinapoyl-7-hydroxytyramine(5), N-cis-feruloyltyramine(6), N-cis-p-coumaroyltyramine(7), N-trans-feruloyltyramine(8), N-trans-feruloyl-3-methoxytyramine(9), and N-trans-feruloyl-7-hydroxytyramine(10). Compound 1 is a new compound. Compounds 2-7 are obtained from the plants of Papaveraceae for the first time, while compounds 8-10 are firstly isolated from C. edulis.