RESUMEN
Strictinin is a relatively tiny ellagitannin, which is found in many plants as a minor constituent. Catechins are known as the major constituents in the young leaves of most tea plants, while strictinin was found as a major constituent in the Pu'er tea plant. In some Pu'er tea varieties, strictinin was identified as the most abundant phenolic compound rather than catechins. In the past decade, strictinin was demonstrated to possess several functional activities, including antiviral, antibacterial, anti-obesity, laxative, anticaries, anti-allergic, antipsoriatic, antihyperuricemia, antidiabetic, and anticancer effects. These functional activities were in accordance with the therapeutic effects empirically perceived for Pu'er tea. Evidently, strictinin is the key ingredient in Pu'er tea that acts as a herbal medicine. In functionally-based applications, an instant powder of Pu'er tea infusion was formulated as an active raw material to be supplemented in food, cosmetics, and beverages; a new type of tea named Bitter Citrus Tzen Tea was developed by combining three teas empirically consumed to expel the cold, and new edible oral care products were designed for caries prevention by supplementation with Pu'er tea extract. More functional activities and practical applications of strictinin are scientifically anticipated in follow-up research.
Asunto(s)
Camellia sinensis , Té , Fenoles , ObesidadRESUMEN
Hyperuricemia, an abnormally high level of blood uric acid, is a major risk factor for gout. Although xanthine oxidase inhibitors were clinically used to lower blood uric acid level, the concerned side effects restricted their utilization. In this study, strictinin, an abundant polyphenol in Pu'er tea, was evaluated for its preventive effects on hyperuricemia. The results showed that the xanthine oxidase activity, uric acid production, and inflammation in AML12 mouse hepatocytes treated with xanthine were significantly reduced by the supplementation of strictinin. Detailed analyses revealed that strictinin inhibited xanthine-induced NLRP3 inflammasome activation. Consistently, the elevated blood uric acid level and the enhanced xanthine oxidase activity in mice treated with potassium oxonate were effectively diminished by strictinin supplementation. Moreover, for the first time, strictinin was found to promote healthy gut microbiota. Overall, strictinin possesses a great potential to be utilized as a functional ingredient for the prevention of hyperuricemia.
RESUMEN
Theacrine and strictinin of Yunnan Kucha tea prepared from a mutant variety of wild Pu'er tea plants were two major ingredients responsible for the anti-influenza activity. As the COVID-19 outbreak is still lurking, developing safe and cost-effective therapeutics is an urgent need. This study aimed to evaluate the effects of these tea compounds on the infection of mouse hepatitis virus (MHV), a ß-coronavirus serving as a surrogate for SARS-CoV. Treatment with strictinin (100 µM), but not theacrine, completely eliminated MHV infection, as indicated by a pronounced reduction in plaque formation, nucleocapsid protein expression, and progeny production of MHV. Subsequently, a time-of-drug addition protocol, including pre-, co-, or post-treatment, was exploited to further evaluate the possible mechanism of antiviral activity mediated by strictinin, and remdesivir, a potential drug for the treatment of SARS-CoV-2, was used as a positive control against MHV infection. The results showed that all three treatments of remdesivir (20 µM) completely blocked MHV infection. In contrast, no significant effect on MHV infection was observed when cells were pre-treated with strictinin (100 µM) prior to infection, while significant inhibition of MHV infection was observed when strictinin was introduced upon viral adsorption (co-treatment) and after viral entry (post-treatment). Of note, as compared with the co-treatment group, the inhibitory effect of strictinin was more striking in the post-treatment group. These results indicate that strictinin suppresses MHV infection by multiple mechanisms; it possibly interferes with viral entry and also critical step(s) of viral infection. Evidently, strictinin significantly inhibited MHV infection and might be a suitable ingredient for protection against coronavirus infection.
Asunto(s)
COVID-19 , Virus de la Hepatitis Murina , Ratones , Animales , Virus de la Hepatitis Murina/metabolismo , Células L , SARS-CoV-2 , China , Té/metabolismoRESUMEN
Muscle atrophy caused by an imbalance between the synthesis and the degradation of proteins is a syndrome commonly found in the elders. Teaghrelin, a natural compound from oolong tea, has been shown to promote cell differentiation and to inhibit dexamethasone-induced muscle atrophy in C2C12 cells. In this study, the therapeutic effects of teaghrelin on muscle atrophy were evaluated in Sprague Dawley rats treated with dexamethasone. The masses of the soleus, gastrocnemius and extensor digitorum longus muscles were reduced in dexamethasone-treated rats, and the reduction of these muscle masses was significantly attenuated when the rats were supplemented with teaghrelin. Accordingly, the level of serum creatine kinase, a marker enzyme of muscle proteolysis, was elevated in dexamethasone-treated rats, and the elevation was substantially reduced by teaghrelin supplementation. A decrease in Akt phosphorylation causing the activation of the ubiquitin-proteasome system and autophagy for protein degradation was detected in the gastrocnemius muscles of the dexamethasone-treated rats, and this signaling pathway for protein degradation was significantly inhibited by teaghrelin supplementation. Protein synthesis via the mTOR/p70S6K pathway was slowed down in the gastrocnemius muscles of the dexamethasone-treated rats and was significantly rescued after teaghrelin supplementation. Teaghrelin seemed to prevent muscle atrophy by reducing protein degradation and enhancing protein synthesis via Akt phosphorylation.
Asunto(s)
Atrofia Muscular , Proteínas Proto-Oncogénicas c-akt , Ratas , Animales , Ratas Sprague-Dawley , Proteínas Proto-Oncogénicas c-akt/metabolismo , Atrofia Muscular/inducido químicamente , Atrofia Muscular/tratamiento farmacológico , Atrofia Muscular/metabolismo , Músculo Esquelético/metabolismo , Dexametasona/efectos adversos , Suplementos DietéticosRESUMEN
The growth hormone secretagogue receptor-1a (GHSR1a) is the endogenous receptor for ghrelin. Activation of GHSR1a participates in many physiological processes including energy homeostasis and eating behavior. Due to its transitory half-life, the efficacy of ghrelin treatment in patients is restricted; hence the development of new adjuvant therapy is an urgent need. This study aimed to establish a cell line stably expressing GHSR1a, which could be employed to screen potential ghrelin agonists from natural compounds. First, by means of lentiviral transduction, the genome of a human HEK293T cell was modified, and a cell platform stably overexpressing GHSR1a was successfully established. In this platform, GHSR1a was expressed as a fusion protein tagged with mCherry, which allowed the monitoring of the dynamic cellular distribution of GHSR1a by fluorescent microscopy. Subsequently, the authenticity of the GHSR1a mediated signaling was further characterized by using ghrelin and teaghrelin, two molecules known to stimulate GHSR1a. The results indicated that both ghrelin and teaghrelin readily activated GHSR1a mediated signaling pathways, presumably via increasing phosphorylation levels of ERK. The specific GHSR1a signaling was further validated by using SP-analog, an antagonist of GHSR1a as well as using a cell model with the knockdown expression of GHSR1a. Molecular modeling predicted that crocin might be a potential ghrelin agonist, and this prediction was further confirmed by the established platform.
Asunto(s)
Carotenoides , Ghrelina , Receptores de Ghrelina , Humanos , Ghrelina/agonistas , Células HEK293 , Receptores de Ghrelina/genética , Receptores de Ghrelina/metabolismo , Transducción de Señal , Carotenoides/farmacologíaRESUMEN
Artificial oil bodies covered by a recombinant surface protein, caleosin fused with histatin 3 (a major human salivary peptide), were employed to explore the relative astringency of eight tea catechins. The results showed that gallate-type catechins were more astringent than non-gallate-type catechins, with an astringency order of epicatechin gallate > epigallocatechin gallate > gallocatechin gallate > catechin gallate > epigallocatechin > epicatechin > gallocatechin > catechin. As expected, the extension of brewing time led to an increase in catechin content in the tea infusion, thus elevating tea astringency. Detailed analysis showed that the enhanced proportion of gallate-type catechins was significantly higher than that of non-gallate-type catechins, indicating that tea astringency was elevated exponentially, rather than proportionally, when brewing time was extended. Rough surfaces were observed on artificial oil bodies when they were complexed with epigallocatechin gallate (a catechin), while a smooth surface was observed on those complexed with rutin (a flavonol glycoside) under an atomic force microscope and a scanning electron microscope. The results indicate that catechins and flavonol glycosides induce the sensation of rough (puckering) and smooth (velvety) astringency in tea, respectively.
Asunto(s)
Catequina , Astringentes/análisis , Catequina/análogos & derivados , Catequina/química , Flavonoles/análisis , Glicósidos/análisis , Humanos , Gotas Lipídicas/química , Sensación , Té/químicaRESUMEN
Tea is a widely consumed beverage prepared using the fresh leaves of Camellia sinensis L. Tea plants are classified into small- and large-leaf varieties. Polyphenol oxidase (PPO), a crucial enzyme in tea manufacturing, catalyzes essential phenolic metabolites into different derivatives. To compare the molecular characteristics of CsPPO between cultivars, we cloned the full-length sequence of CsPPO cDNA from four representative tea cultivars in Taiwan. Amino acid sequence alignment analyses indicated that CsPPO is highly conserved. PPO exhibited similar enzymatic activity in different tea cultivars. Quantitative real-time polymerase chain reaction revealed no significant differences in the CsPPO transcript level between the small- and large-leaf varieties. However, tea harvested in summer and from low-altitude areas had a higher CsPPO transcript level than that harvested in winter and from high-altitude areas. Regulation of CsPPO by temperature was more significant in the small-leaf variety than in the large-leaf variety. The content of flavonoids and the expression of chalcone synthase, anthocyanidin synthase, and anthocyanidin reductase genes involved in the tea flavonoid biosynthesis pathway were higher in the large-leaf than in the small-leaf varieties, suggesting that the large-leaf variety had a higher antioxidative capacity than did the small-leaf variety. Our study compared the molecular properties of CsPPO between two tea varieties and clarified the physiological role of PPO in tea.
Asunto(s)
Camellia sinensis , Catecol Oxidasa , Camellia sinensis/metabolismo , Catecol Oxidasa/genética , Catecol Oxidasa/metabolismo , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Té/genética , Té/metabolismoRESUMEN
Teaghrelins were identified as unique acylated flavonoid tetraglycosides and firstly reported in Chin-shin oolong tea. In the present study, two new teaghrelin-like compounds (1 and 2) were purified and characterised from Assam tea varieties collected in Thailand. Their chemical structures were constructed by the spectroscopic and spectrometric analysis. These two teaghrelin-like compounds were also not supposed to exhibit significant ghrelin receptor affinity according to the structural comparison with those teaghrelin-like compounds previously reported. In addition, compounds 1 and 2 did not display notable anti-inflammatory activity in human neutrophils assay.[Formula: see text].
Asunto(s)
Camellia sinensis , Flavonoides , Humanos , Receptores de Ghrelina , Té , TailandiaRESUMEN
Caffeine has been reported to induce anti-tumor immunity for attenuating breast cancer by blocking the adenosine 2A receptor. Molecular modeling showed that theacrine, a purine alkaloid structurally similar to caffeine, might be an antagonist of the adenosine 2A receptor equivalent to or more effective than caffeine. Theacrine was further demonstrated to be an effective antagonist of the adenosine 2A receptor as its concurrent supplementation significantly reduced the elevation of AMPK phosphorylation level in MCF-7 human breast cells induced by CGS21680, an agonist of adenosine 2A receptors. In an animal model, the development of mammary carcinoma induced by 7,12-Dimethylbenz[a]anthracene in Sprague-Dawley rats could be attenuated by daily supplement of theacrine of 50 or 100 mg/kg body weight. Both expression levels of cleaved-caspase-3/pro-caspase-3 and granzyme B in tumor tissues were significantly elevated when theacrine was supplemented, indicating the induction of programmed cell death in tumor cells might be involved in the attenuation of mammary carcinoma. Similar to the caffeine, significant elevation of interferon-γ and tumor necrosis factor-α was observed in the serum and tumor tissues of rats after the theacrine supplement of 50 mg/kg body weight. Taken together, theacrine is an effective antagonist of adenosine 2A receptors and possesses great potential to be used to attenuate breast cancer.
Asunto(s)
Antagonistas del Receptor de Adenosina A2/farmacología , Neoplasias Mamarias Experimentales , Proteínas de Neoplasias , Receptor de Adenosina A2A/metabolismo , Ácido Úrico/análogos & derivados , Animales , Femenino , Humanos , Células MCF-7 , Neoplasias Mamarias Experimentales/inducido químicamente , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Neoplasias Mamarias Experimentales/metabolismo , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/metabolismo , Ratas , Ratas Sprague-Dawley , Ácido Úrico/farmacologíaRESUMEN
Teaghrelins, identified originally in Chin-shin oolong tea, are unique acylated flavonoid tetraglycosides and proposed to be potential oral analogues of ghrelin. In the present study, two new teaghrelin-like compounds were characterized from tea cultivars (TTES No. 12), and their chemical structures were established by the spectroscopic and spectrometric analysis. However, due to the different location of rhamnose, these two teaghrelin-like compounds may not show significant ghrelin receptor affinity.[Figure: see text].
Asunto(s)
Camellia sinensis/química , Flavonoides/química , Acilación , Flavonoides/metabolismo , Ghrelina/química , Ghrelina/farmacología , Espectroscopía de Resonancia Magnética , Simulación del Acoplamiento Molecular , Estructura Molecular , Extractos Vegetales/química , Receptores de Ghrelina/metabolismo , Espectrometría de Masa por Ionización de Electrospray , Té/químicaRESUMEN
The prevalence and incidence of Parkinson's disease (PD), an age-related neurodegenerative disease, are higher among elderly people. Independent of etiology, dysfunction and loss of dopaminergic neurons are common pathophysiological changes in PD patients with impaired motor and non-motor function. Currently, preventive or therapeutic treatment for combating PD is limited. The ghrelin axis and ghrelin receptor have been implicated in the preservation of dopaminergic neurons and have potential implications in PD treatment. Teaghrelin, a compound originating from Chin-Shin Oolong tea, exhibits ghrelin agonist activity. In this study, the neuroprotective potential of teaghrelin against PD was explored in a cell model in which human neuroblastoma SH-SY5Y cells were treated with the mitochondrial toxin 1-methyl-4-phenylpyridinium (MPP+). Upon MPP+ exposure, SH-SY5Y cells exhibited decreased mitochondrial complex I activity and apoptotic cell death. Teaghrelin activated AMP-activated protein kinase (AMPK)/sirtuin 1(SIRT1)/peroxisome proliferator-activated receptor gamma (PPARγ) coactivator-1α (PGC-1α) and extracellular signal-regulated kinases 1 and 2 (ERK1/2) pathways to antagonize MPP+-induced cell death. Herein, we propose that teaghrelin is a potential candidate for the therapeutic treatment of PD.
Asunto(s)
1-Metil-4-fenilpiridinio/toxicidad , Adenilato Quinasa/metabolismo , Camellia sinensis/química , Supervivencia Celular/efectos de los fármacos , Ghrelina/agonistas , Sirtuina 1/metabolismo , Adenilato Quinasa/genética , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Sirtuina 1/genéticaRESUMEN
Mulberry (Morus alba) leaf is traditionally consumed as a functional tea with remedial effects, such as preventing aging-related diseases. Two similar compounds, quercetin 3-O-malonylglucoside, and kaempferol 3-O-malonylglucoside, were detected in mulberry leaves and found to be structural recombinant composites of teaghrelin and emoghrelin, two classes of non-peptidyl compounds functionally identified as analogs of ghrelin. Molecular modeling showed that these two mulberry compounds were able to enter and interact with the ghrelin receptor and theoretical calculation revealed that they were similar to emoghrelin but slightly weaker than teaghrelin in terms of interaction with the receptor. The relatively abundant compound, quercetin 3-O-malonylglucoside was subjected to a bioactivity assay, and the result confirmed that it was able to increase the growth hormone secretion of rat anterior pituitary cells. It seems that quercetin 3-O-malonylglucoside is also a functional analog of ghrelin and presumably a key ingredient for the anti-aging activity of mulberry leaves. PRACTICAL APPLICATIONS: According to this study, quercetin 3-O-malonylglucoside and kaempferol 3-O-malonylglucoside are suggested to serve as active ingredients in tea products prepared from mulberry leaves. Contents of these two compounds might be used as key factors for breeding or screening mulberry varieties for commercial cultivation. Moreover, water extract of mulberry leaves containing these compounds can be used as an adequate supplement for functional food.
Asunto(s)
Morus , Animales , Ghrelina , Glucósidos , Extractos Vegetales/farmacología , Hojas de la Planta , Quercetina/farmacología , RatasRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Kucha tea plant (Camellia assamica var. kucha Chang et Wang) is regarded as a mutant variety of wild Pu'er tea plant found in few mountain areas of Yunnan, China. Its fresh young leaves and shoots are picked by the indigenous aborigines in these local areas to prepare an herbal tea for the treatment of common cold empirically. MATERIALS AND METHODS: Two extra compounds of relative abundance were detected in Kucha tea in comparison with Pu'er tea, and their chemical structures were identified as chlorogenic acid and theacrine. These two compounds as well as two major compounds, strictinin and caffeine, in Kucha tea were evaluated for their cytotoxicity and inhibitory effects on human influenza virus A/Puerto Rico/8/34 by analyzing viral protein expression and progeny production. RESULTS: No or low cytotoxicity was detected for the four Kucha compounds when their concentrations were below 100 µM. Expression of viral NS1 protein was significantly inhibited by chlorogenic acid, theacrine or strictinin, but not caffeine at a concentration of 100 µM. The relative inhibitory potency was detected as chlorogenic acid < theacrine < strictinin, and both theacrine and strictinin displayed significant inhibition at a concentration of 50 µM. According to a plaque assay, viral progeny production was significantly reduced by theacrine or strictinin, but not by chlorogenic acid or caffeine under the same concentration of 100 µM. CONCLUSION: It is suggested that theacrine and strictinin are two major ingredients responsible for the anti-influenza activity of Yunnan Kucha tea traditionally used for the treatment of common cold.
Asunto(s)
Alphainfluenzavirus/efectos de los fármacos , Antivirales/farmacología , Camellia sinensis , Fenoles/farmacología , Tés de Hierbas , Ácido Úrico/análogos & derivados , Animales , Antivirales/aislamiento & purificación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Perros , Humanos , Alphainfluenzavirus/fisiología , Células de Riñón Canino Madin Darby , Fenoles/aislamiento & purificación , Hojas de la Planta , Ácido Úrico/aislamiento & purificación , Ácido Úrico/farmacologíaRESUMEN
Excessive food consumption and insufficient exercise lead to the prevalence of metabolic syndrome in modern life, which consequently increases the risk of many chronic diseases. Magnesium lithospermate B (MLB) from Danshen has been demonstrated to improve metabolic changes in high-fat diet-fed rats with metabolic syndrome. In this study, Mg2+ in MLB was successfully replaced with Zn2+ to form zinc lithospermate B (ZLB) complex. MLB (10 mg/kg /day) and ZLB of various concentrations (1, 2.5, 5, and 10 mg/kg/day) were prepared and examined for their therapeutic effects on metabolic syndrome induced in rats fed with a high-fat diet. The results showed that both MLB and ZLB were able to recover or alleviate the abnormal physiological states of high-fat diet-fed rats including weight gain, epididymal fat accumulation, fatty liver, retarded blood lipid and glucose metabolism putatively caused by insulin resistance, and elevated levels of proinflammatory cytokine, leptin, and oxidative stress. In an overall view of the animal study, the effectiveness of ZLB supplementation seemed to be better than that of MLB supplementation for the recovery of high-fat-fed rats from metabolic syndrome.
Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Síndrome Metabólico/tratamiento farmacológico , Zinc/farmacología , Animales , Glucemia/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Medicamentos Herbarios Chinos/química , Humanos , Insulina/metabolismo , Leptina/sangre , Lípidos/sangre , Magnesio/química , Magnesio/farmacología , Síndrome Metabólico/etiología , Síndrome Metabólico/patología , Estrés Oxidativo/efectos de los fármacos , Ratas , Salvia miltiorrhiza , Aumento de Peso/efectos de los fármacos , Zinc/químicaRESUMEN
INTRODUCTION: Recently, the fresh leaves of Aquilaria trees have been processed as food products such as agarwood tea due to its beneficial medicinal properties. However, there have not been any reported analytical methods to quantify the bioactive principles in the processed products. OBJECTIVE: A rapid and sensitive ultrahigh-performance liquid chromatography (UHPLC) coupled with electrospray ionisation (ESI) tandem mass spectrometry (MS/MS) method was developed and validated for the simultaneous determination of 10 bioactive components in Aquilaria leaf tea. METHODS: The UHPLC-MS/MS was used for quantification operated in multiple reaction monitoring (MRM) mode. The optimised chromatographic parameters were conducted on a Shim-pack XR-ODS II column and mobile phases consisted of acetonitrile and 0.1% formic acid in water. RESULTS: All the samples were analysed within 20 min. The established method showed excellent linearity (R2 > 0.9988), good repeatability with all the relative standard deviation values lower than 3.27%, and satisfactory recovery (79.72-119.22%). The matrix effect factors ranged from 87.65 to 97.27% in the examination. The developed method was applied to the determination of 10 bioactive principles (1-10) in six different Aquilaria leaf tea samples. Among the analytes, mangiferin (1) and iriflophenone 2-O-α-l-rhamnopyranoside (2) were the most abundant compounds in the extracts of Aquilaria leaf tea, and it indicated that these biotech products may possess laxative effects. CONCLUSION: This proposed method appeared to be a useful tool for the quality control of commercial products of Aquilaria leaf tea and thus provided an analytical reference for herbal drinks.
Asunto(s)
Espectrometría de Masas en Tándem , Thymelaeaceae , Cromatografía Líquida de Alta Presión , Hojas de la Planta , Reproducibilidad de los Resultados , TéRESUMEN
This study aimed to investigate the effects of teaghrelin, an active ingredient of Chin-shin oolong tea, on murine C2C12 myoblast cells. Under high serum conditions, teaghrelin inhibited C2C12â¯cell proliferation, indicating a cell cycle arrest and cessation of proliferative progression. Teaghrelin promoted pro-differentiation of C2C12â¯cells as evidenced by a progressively elongated morphology, as well as the induction of muscle specific myogenin, myosin heavy chain (MHC), and MyoD. The formation of multinucleated myotubes, and the increase of MHC-positive immunoreactivity within the myotubes, further reflected a complete differentiation and maturation of the contractile skeletal muscle cells induced by teaghrelin. Like ghrelin, teaghrelin attenuated dexamethasone-decreased myotube diameter, indicating its protective effects against skeletal muscle atrophy. Additionally, the expressions of Atrogin-1 and MuRF-1 ubiquitin E3 ligase were reduced. In conclusion, the results highlight a possibility of developing teaghrelin as a functional food for the prevention or therapeutic treatment of disease-associated skeletal muscle atrophy.
Asunto(s)
Diferenciación Celular/efectos de los fármacos , Ghrelina/farmacología , Fibras Musculares Esqueléticas/efectos de los fármacos , Atrofia Muscular/tratamiento farmacológico , Mioblastos/efectos de los fármacos , Extractos Vegetales/farmacología , Té/química , Animales , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Ratones , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Proteína MioD/metabolismo , Mioblastos/metabolismo , Miogenina/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Sustancias Protectoras/farmacología , Transducción de Señal/efectos de los fármacos , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
Teaghrelins are unique acylated flavonoid tetraglycosides originally identified in Chin-shin oolong tea, and proposed to be potential oral analogs of ghrelin. Two acylated flavonoid tetraglycosides were isolated from Shy-jih-chuen oolong tea, and their chemical structures were determined to be quercetin and kaempferol 3-O-[α-L-arabinopyranosyl(1 â 3)][2"-O-(E)-p-coumaroyl] [ß-D-glucopyranosyl(1 â 3)-α-L-rhamnopyranosyl(1 â 6)]-ß-D-glucoside. These two compounds were extremely similar to the two teaghrelins (teaghrelin-1 and teaghrelin-2) in Chin-shin oolong tea by simply replacing a glucopyranosyl group with an arabinopyranosyl group. Molecular modeling showed that the two putative teaghrelins identified in Shy-jih-chuen docked to and interacted with the ghrelin receptor as well as teaghrelin-1 and teaghrelin-2. Mixture of these two putative teaghrelins was shown to enhance the release of growth hormone from primary anterior pituitary cells of rats. The results suggest that two teaghrelins, named teaghrelin-3 and teaghrelin-4, are present in Shy-jih-chuen oolong tea and possess biological activities analogous to teaghrelins in Chin-shin oolong tea. PRACTICAL APPLICATIONS: According to this study, teaghrelin-3 and teaghrelin-4 may be regarded as active ingredients for the quality control of Shy-jih-chuen oolong tea. The content of teaghrelins may serve as a key factor for the farmers to select new tea plants in their next propagation of Shy-jih-chuen cultivar. Crude water extract of Shy-jih-chuen oolong tea containing teaghrelins is considered to be an adequate food supplement or additive in functional food products.
Asunto(s)
Camellia sinensis/química , Ghrelina/química , Extractos Vegetales/química , Flavonoides/química , Hojas de la Planta/química , Receptores de Ghrelina/química , Té/químicaRESUMEN
Lithospermic acid B (LSB), the major water-soluble ingredient of Salvia miltiorrhiza (Danshen), has been shown to be an active ingredient responsible for the therapeutic effects of this traditional Chinese herb used to treat cardiac disorders. This study aimed to develop an indirect competitive enzyme linked immunosorbent assay (ELISA) for the detection of LSB. Firstly, LSB was chemically conjugated to a modified oil-body protein, lysine-enriched caleosin, recombinantly expressed in Escherichia coli. Antibodies against LSB (Ab-LSB) were successfully generated by immunizing hens with artificial oil bodies constituted with the LSB-conjugated caleosin. Western blotting showed that Ab-LSB specifically recognized LSB, but not the carrier protein, lysine-enriched caleosin. To detect LSB via indirect competitive ELISA, LSB was conjugated with bovine serum albumin (LSB-BSA) and coated on a microplate. The binding between Ab-LSB and LSB-BSA on the microplate was competed dose-dependently in the presence of free LSB with a concentration ranging from 5 to 5 × 104 ng/mL. The IC50 value was approximately determined to be 120 ng/mL for LSB regardless of its complex with a metal ion of Na+, K+ or Mg2+.
Asunto(s)
Anticuerpos/inmunología , Benzofuranos/aislamiento & purificación , Depsidos/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Salvia miltiorrhiza/química , Anticuerpos/química , Especificidad de Anticuerpos/inmunología , Benzofuranos/química , Benzofuranos/inmunología , Benzofuranos/uso terapéutico , Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/inmunología , Depsidos/química , Depsidos/inmunología , Depsidos/uso terapéutico , Cardiopatías/tratamiento farmacológico , Humanos , Medicina Tradicional China , Proteínas de Plantas/química , Proteínas de Plantas/inmunologíaRESUMEN
Cistanche species, the ginseng of the desert, has been recorded to possess many biological activities in traditional Chinese pharmacopoeia and has been used as an anti-aging medicine. Three phenylethanoid glycosides-echinacoside, tubuloside A, and acteoside-were detected in the water extract of Cistanche tubulosa (Schenk) R. Wight and the major constituent, echinacoside, was further purified. Echinacoside of a concentration higher than 10-6 M displayed significant activity to stimulate growth hormone secretion of rat pituitary cells. Similar to growth hormone-releasing hormone-6, a synthetic analog of ghrelin, the stimulation of growth hormone secretion by echinacoside was inhibited by [D-Arg¹, D-Phe5, D-Trp7,9, Leu11]-substance P, an inverse agonist of the ghrelin receptor. Molecular modeling showed that all the three phenylethanoid glycosides adequately interacted with the binding pocket of the ghrelin receptor, and echinacoside displayed a slightly better interaction with the receptor than tubuloside A and acteoside. The results suggest that phenylethanoid glycosides, particularly echinacoside, are active constituents putatively responsible for the anti-aging effects of C. tubulosa and may be considered to develop as non-peptidyl analogues of ghrelin.
Asunto(s)
Cistanche/química , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Hormona del Crecimiento/biosíntesis , Receptores de Ghrelina/agonistas , Animales , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Cistanche/metabolismo , Glicósidos/química , Masculino , Espectrometría de Masas , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , RatasRESUMEN
Two new sesquiterpenoids peltopterins A and B (compounds 1 and 2) and fifty-two known compounds were isolated from the methanol extract of P. pterocarpum and their chemical structures were established through spectroscopic and mass spectrometric analyses. The isolates 40, 43, 44, 47, 48, 51 and 52 exhibited potential inhibitory effects of superoxide anion generation or elastase release.