Phytochemical profile and biological activities of Bromelia antiacantha extracts / Perfil fitoquímico e atividades biológicas de extratos de Bromelia antiacantha

Reports from popular medicine usually act as a basis for the development of new drugs from natural compounds with therapeutic actions for serious diseases and prevalence such as cancer. Bromelia antiacantha Bertol. is a species of the Bromeliaceae family, considered an unconventional food plant, found in the south and midwest regions of Brazil. Despite the high nutritional content and pharmacological potential of its fruits, few scientific studies report its biological actions. Thus, this study evaluates the phytochemical profile of aqueous and ethanol extracts obtained from B. antiacantha fruits, as well as their possible antioxidant, antitumor, and cytotoxic activities. The aqueous extract exhibited phenolic compounds and flavonoids, while ethanol extracts indicated the presence of flavonoids and coumarin in their composition, regardless of the region of collection. The ethanolic extract demonstrated a more promising antioxidant effect than the aqueous extract and also induced a significant inhibition in the viability of human cervical cancer cells of the SiHa strain. In addition, treatment with both extracts did not alter the viability of non-tumor cells of the immortalized human keratinocyte lineage (HaCaT). These results bring new data about extracts obtained from a native plant, edible and traditionally used in popular medicine, opening new perspectives for its possible therapeutic application.

Relatos da medicina popular costumam atuar como referencial para o desenvolvimento de novos fármacos a partir de moléculas naturais com ações terapêuticas para doenças de alta gravidade e prevalência como o câncer. Bromelia antiacantha Bertol. é uma espécie da família Bromeliaceae, considerada uma planta alimentícia não convencional (PANC), encontrada nas regiões sul e centro-oeste do Brasil. Apesar do alto teor nutritivo e potencial farmacológico de seus frutos, poucos estudos científicos relatam suas ações biológicas. Desta forma, este estudo avalia o perfil fitoquímico de extratos aquoso e etanólico obtidos de frutos de B. antiacantha, bem como a sua possível ação antioxidante, antitumoral e citotóxica. O extrato aquoso apresentou compostos fenólicos e flavonoides, enquanto os extratos etanólicos apontam a presença de flavonóides e cumarina em sua composição, independente da região de coleta. O extrato etanólico demonstrou efeito antioxidante mais promissor do que o extrato aquoso e também induziu uma inibição significativa na viabilidade de células humanas de câncer cervical da linhagem SiHa. Além disso, o tratamento com ambos extratos não alterou a viabilidade de células não tumorais da linhagem de queratinócitos humanos imortalizados (HaCaT). Estes dados trazem novas informações sobre extratos obtidos de uma espécie vegetal nativa, comestível e já utilizada tradicionalmente, mas abrindo novas perspectivas quanto a possíveis aplicações terapêuticas.

In vivo Gonadoprotective Effects of Myricetin on Cisplatin- Induced Testicular Damage via Suppression of TLR4/NF-kB Inflammation Pathway and Heat-Shock Response / Efectos Gonadoprotectores in vivo de la Miricetina sobre el Daño Testicular Inducido por Cisplatino Mediante la Supresión de la Vía de Inflamación TLR4/NF-kB y la Respuesta al Choque Térmico

SUMMARY: The aim of this study is to reveal the gonadoprotective effects of myricetin (MYC), which has many biological properties, on cisplatin (CP)-induced testicular damage in rats. For this purpose, 40 male Wistar albino rats were divided into 4 groups as Control (group given no treatment), MYC (group given 5 mg/kg/i.p myricetin for 7 days), CP (group given 7 mg/kg/i.p cisplatin at 7th day) and MYC + CP (group given 5 mg/kg/i.p myricetin for 7 days before 7 mg/kg/i.p cisplatin injection). After administrations, testicular tissues of animals were extracted and processed according to tissue processing protocol. Hematoxylin & Eosin staining were performed to evaluate the histopathological changes and Johnsen'sTesticular Biopsy Score (JTBS) was applied and mean seminiferous tubule diameters (MSTD) were measured to compare experimental groups in terms of histopathological changes. Moreover, TLR4, NF-kB, HSP70 and HSP90 expression levels were detected by immunohistochemical staining and the density of immunoreactivity were measured to determine the difference in the expression levels of these factors among groups. Additionally, testicular apoptosis was detected via TUNEL assay. JTBS and MSTD data were significantly lower in CP group compared to other groups and MYC administrations significantly protects testicular tissue against CP-induced damage. Moreover, TLR4, NF-kB, HSP70 and HSP90 expressions and apoptotic cells significantly increased in the CP group (p<0.05). However, MYC administrations exerted a strong gonadoprotective effect on testicular tissue in terms of these parameters in MYC+CP group (p<0.05). According to our results, we suggested that MYC can be considered as a protective agent against cisplatin-induced testicular damage.

El objetivo de este estudio es revelar los efectos gonadoprotectores de la miricetina (MYC), que tiene muchas propiedades biológicas, sobre el daño testicular inducido por cisplatino (CP) en ratas. Para este propósito, se dividieron 40 ratas albinas Wistar macho en 4 grupos: Control (grupo que no recibió tratamiento), MYC (grupo que recibió 5 mg/kg/i.p de miricetina durante 7 días), CP (grupo que recibió 7 mg/kg/i.p de cisplatino al séptimo día) y MYC + CP (grupo que recibió 5 mg/ kg/i.p de miricetina durante 7 días antes de la inyección de 7 mg/ kg/i.p de cisplatino). Después de las administraciones, se extrajeron y procesaron tejidos testiculares de animales según el protocolo de procesamiento de tejidos. Se realizó tinción con hematoxilina y eosina para evaluar los cambios histopatológicos y se aplicó la puntuación de biopsia testicular de Johnsen (JTBS) y se midieron los diámetros medios de los túbulos seminíferos (MSTD) para comparar los grupos experimentales en términos de cambios histopatológicos. Además, los niveles de expresión de TLR4, NF-kB, HSP70 y HSP90 se detectaron mediante tinción inmunohistoquímica y se midió la densidad de inmunorreactividad para determinar la diferencia en los niveles de expresión de estos factores entre los grupos. Además, se detectó apoptosis testicular mediante el ensayo TUNEL. Los datos de JTBS y MSTD fueron significativamente más bajos en el grupo CP en comparación con otros grupos y las administraciones de MYC protegen significativamente el tejido testicular contra el daño inducido por CP. Además, las expresiones de TLR4, NF-kB, HSP70 y HSP90 y las células apoptóticas aumentaron significativamente en el grupo CP (p<0,05). Sin embargo, las administraciones de MYC ejercieron un fuerte efecto gonadoprotector sobre el tejido testicular en términos de estos parámetros en el grupo MYC+CP (p<0,05). Según nuestros resultados, sugerimos que MYC puede considerarse como un agente protector contra el daño testicular inducido por cisplatino.

Flavonoids from the roots and rhizomes of Sophoratonkinensis and their in vitro anti-SARS-CoV-2 activity / 中国天然药物

Acute respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had caused a global pandemic since 2019, and posed a serious threat to global health security. Traditional Chinese medicine (TCM) has played an indispensable role in the battle against the epidemic. Many components originated from TCMs were found to inhibit the production of SARS-CoV-2 3C-like protease (3CLpro) and papain-like protease (PLpro), which are two promising therapeutic targets to inhibit SARS-CoV-2. This study describes a systematic investigation of the roots and rhizomes of Sophora tonkinensis, which results in the characterization of 12 new flavonoids, including seven prenylated flavanones (1-7), one prenylated flavonol (8), two prenylated chalcones (9-10), one isoflavanone (11), and one isoflavan dimer (12), together with 43 known compounds (13-55). Their structures including the absolute configurations were elucidated by comprehensive analysis of MS, 1D and 2D NMR data, and time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculations. Compounds 12 and 51 exhibited inhibitory effects against SARS-CoV-2 3CLpro with IC50 values of 34.89 and 19.88 μmol·L-1, repectively while compounds 9, 43 and 47 exhibited inhibitory effects against PLpro with IC50 values of 32.67, 79.38, and 16.74 μmol·L-1, respectively.

Bavachin induces apoptosis in colorectal cancer cells through Gadd45a via the MAPK signaling pathway / 中国天然药物

Bavachin is a dihydroflavonoid compound isolated from Psoralea corylifolia, and exhibits anti-bacterial, anti-inflammatory, anti-tumor and lipid-lowering activities. Recent attention has gradually drawn on bavachin-induced apoptosis in many human cancer cell lines. However, the anti-cancer effects and related mechanisms in colorectal cancer remain unknown. Here, we investigated the effects of bavachin on colorectal cancer in vivo and in vitro. The results showed that bavachin inhibited the proliferation of human colorectal cancer cells and induce apoptosis. These changes were mediated by activating the MAPK signaling pathway, which significantly up-regulated the expression of Gadd45a. Furthermore, Gadd45a silencing obviously attenuated bavachin-mediated cell apoptosis. Inhibition of the MAPK signaling pathway by JNK/ERK/p38 inhibitors also weakened the up-regulation of Gadd45a by bavachin. The anticancer effect of bavachin was also validated using a mouse xenograft model of human colorectal cancer. In conclusion, these findings suggest that bavachin induces the apoptosis of colorectal cancer cells through activating the MAPK signaling pathway.

Effectiveness of Scutellaria baicalensis Georgi root in pregnancy-related diseases: A review / 中西医结合学报

The root of Scutellaria baicalensis Georgi, also called Huangqin, is frequently used in traditional Chinese medicine. In ancient China, S. baicalensis root was used to clear heat, protect the fetus, and avoid a miscarriage for thousands of years. In modern times, pregnancy-related diseases can seriously affect maternal and fetal health, but few systematic studies have explored the mechanisms and potential targets of S. baicalensis root in the treatment of pregnancy-related diseases. Flavonoids (baicalein, wogonin and oroxylin A) and flavonoid glycosides (baicalin and wogonoside) are the main chemical components in the root of S. baicalensis. This study presents the current understanding of the major chemical components in the root of S. baicalensis, focusing on their traditional uses, potential therapeutic effects and ethnopharmacological relevance to pregnancy-related disorders. The mechanisms, potential targets and experimental models of S. baicalensis root for ameliorating pregnancy-related diseases, such as recurrent spontaneous abortion, preeclampsia, preterm birth, fetal growth restriction and gestational diabetes mellitus, are highlighted.

Flavonoid-Rich Extract of Oldenlandia diffusa (Willd.) Roxb. Inhibits Gastric Cancer by Activation of Caspase-Dependent Mitochondrial Apoptosis / 中国结合医学杂志

OBJECTIVE@#To evaluate the apoptosis and cycle arrest effects of Oldenlandia diffusa flavonoids on human gastric cancer cells, determine the action mechanisms in association with the mitochondrial dependent signal transduction pathway that controls production of reactive oxygen species (ROS), and evaluate the pharmacodynamics of a mouse xenotransplantation model to provide a reference for the use of flavonoids in prevention and treatment of gastric cancer.@*METHODS@#Flavonoids were extracted by an enzymatic-ultrasonic assisted method and purified with D-101 resin. Bioactive components were characterized by high-performance liquid chromatography. Cell lines MKN-45, AGS, and GES-1 were treated with different concentrations of flavonoids (64, 96, 128, 160 µg/mL). The effect of flavonoids on cell viability was evaluated by MTT method, and cell nuclear morphology was observed by Hoechst staining. The apoptosis rate and cell cycle phases were measured by flow cytometry, the production of ROS was detected by laser confocal microscope, the mitochondrial membrane potential (MMP) were observed by fluorescence microscope, and the expression of apoptotic proteins related to activation of mitochondrial pathway were measured by immunoblotting. MKN-45 cells were transplanted into BALB/c nude mice to establish a xenograft tumor model. Hematoxylin and eosin staining was used to reveal the subcutaneous tumor tissue. The tumor volume and tumor weight were measured, the expression levels of proliferation markers proliferating cell nuclear antigen (PCNA) and Ki-67 were detected by immunohistochemistry, and the expression levels of CA72-4 were measured by enzyme linked immunosorbent assay.@*RESULTS@#Oldenlandia diffusa flavonoids inhibited proliferation of MKN-45 and AGS human gastric cancer cells, arrested the cell cycle in G1/S phase, induced accumulation of ROS in the process of apoptosis, and altered MMP. In addition, flavonoids increased Apaf-1, Cleaved-Caspase-3, and Bax, and decreased Cyclin A, Cdk2, Bcl-2, Pro-Caspase-9, and Mitochondrial Cytochrome C (P<0.05). The MKN-45 cell mouse xenotransplantation model further clarified the growth inhibitory effect of flavonoids towards tumors. The expression levels of PCNA and Ki-67 decreased in each flavonoid dose group, the expression level of CA72-4 decreased (P<0.05).@*CONCLUSION@#Flavonoids derived from Oldenlandia diffusa can inhibit proliferation and induce apoptosis of human gastric cancer cells by activating the mitochondrial controlled signal transduction pathway.

Therapeutic Properties of Flavonoids in Treatment of Cancer through Autophagic Modulation: A Systematic Review / 中国结合医学杂志

Cancers have high morbidity and mortality rates worldwide. Current anticancer therapies have demonstrated specific signaling pathways as a target in the involvement of carcinogenesis. Autophagy is a quality control system for proteins and plays a fundamental role in cancer carcinogenesis, exerting an anticarcinogenic role in normal cells and can inhibit the transformation of malignant cells. Therefore, drugs aimed at autophagy can function as antitumor agents. Flavonoids are a class of polyphenolic secondary metabolites commonly found in plants and, consequently, consumed in diets. In this review, the systematic search strategy was used, which included the search for descriptors "flavonoids" AND "mTOR pathway" AND "cancer" AND "autophagy", in the electronic databases of PubMed, Cochrane Library, Web of Science and Scopus, from January 2011 to January 2021. The current literature demonstrates that flavonoids have anticarcinogenic properties, including inhibition of cell proliferation, induction of apoptosis, autophagy, necrosis, cell cycle arrest, senescence, impaired cell migration, invasion, tumor angiogenesis and reduced resistance to multiple drugs in tumor cells. We demonstrate the available evidence on the roles of flavonoids and autophagy in cancer progression and inhibition. (Registration No. CRD42021243071 at PROSPERO).

Cloning and catalytic analysis of Isatis indigotica chalcone isomerase in vitro / 中国中药杂志

Chalcone isomerase is a key rate-limiting enzyme in the biosynthesis of flavonoids in higher plants, which determines the production of flavonoids in plants. In this study, RNA was extracted from different parts of Isatis indigotica and reverse-transcribed into cDNA. Specific primers with enzyme restriction sites were designed, and a chalcone isomerase gene was cloned from I. indigotica, named IiCHI. IiCHI was 756 bp in length, containing a complete open reading frame and encoding 251 amino acids. Homology analysis showed that IiCHI was closely related to CHI protein of Arabidopsis thaliana and had typical active sites of chalcone isomerase. Phylogenetic tree analysis showed that IiCHI was classified into type Ⅰ CHI clade. Recombinant prokaryotic expression vector pET28a-IiCHI was constructed and purified to obtain IiCHI recombinant protein. In vitro enzymatic analysis showed that the IiCHI protein could convert naringenin chalcone into naringenin, but could not catalyze the production of liquiritigenin by isoliquiritigenin. The results of real-time quantitative polymerase chain reaction(qPCR) showed that the expression level of IiCHI in the aboveground parts was higher than that in the underground parts and the expression level was the highest in the flowers of the aboveground parts, followed by leaves and stems, and no expression was observed in the roots and rhizomes of the underground parts. This study has confirmed the function of chalcone isomerase in I. indigotica and provided references for the biosynthesis of flavonoid components.

Research progress on chemical constituents and pharmacological activities of Viola plants / 中国中药杂志

There are 500 species of Viola(Violaceae) worldwide, among which 111 species are widely distributed in China and have a long medicinal history and wide varieties. According to the authors' statistics, a total of 410 compounds have been isolated and identified from plants of this genus, including flavonoids, terpenoids, phenylpropanoids, organic acids, nitrogenous compounds, sterols, saccharides and their derivatives, volatile oils and cyclotides. The medicinal materials from these plants boast anti-microbial, anti-viral, anti-oxidant and anti-tumor activities. This study systematically reviewed the chemical constituents and pharmacological activities of Viola plants to provide a basis for further research and clinical application.

Rapid flavonoid-focused sub-chemome characterization of Draconis Sanguis using UPLC-Q-TOF-MS in combination with molecular weight imprinting and mass defect filtering / 中国中药杂志

Draconis Sanguis is a precious Chinese medicinal material for activating blood and resolving stasis, and its effective components are flavonoids. However, the structural diversity of flavonoids in Draconis Sanguis brings great challenges to the in-depth chara-cterization of its chemical composition profiles. To clarify the substance basis of Draconis Sanguis, ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was used in this study to acquire MS data of Draconis Sanguis. The molecular weight imprinting(MWI) and mass defect filtering(MDF) were developed for rapid screening of flavonoids in Draconis Sanguis. Full-scan MS and MS~2 were recorded within the mass range m/z 100-1 000 in positive ion mode. Accor-ding to previous literature, MWI was employed to hunt for reported flavonoids in Draconis Sanguis, and the mass tolerance range of [M+H]~+ was set as ±10×10~(-3). A five-point MDF screening frame was further constructed to narrow the screening range of flavonoids from Draconis Sanguis. Combined with diagnostic fragment ions(DFI) and neutral loss(NL) as well as mass fragmentation pathways, 70 compounds were preliminarily identified from the extract of Draconis Sanguis, including 5 flavan oxidized congeners, 12 flavans, 1 dihydrochalcones, 49 flavonoids dimers, 1 flavonoids trimer and 2 flavonoid derivatives. This study clarified the chemical composition of flavonoids in Draconis Sanguis. Moreover, it also showed that high-resolution MS combined with data post-processing methods such as MWI and MDF could achieve rapid characterization of the chemical composition in Chinese medicinal materials.

Content analysis and quality evaluation of main active components and mineral elements of Cynomorium songaricum in different habitats / 中国中药杂志

To clarify the content characteristics of the main active components and mineral elements of Cynomorium songaricum under different habitat conditions, and further explore the relationship between the quality of C. songaricum and habitats, this study took C. songaricum from 25 different habitats in China as the research object, and measured the contents of 8 main active components and 12 mineral elements separately. Diversity analysis, correlation analysis, principal component analysis and cluster analysis were carried out. The results showed that the genetic diversity of total flavonoids, ursolic acid, ether extract, potassium(K), phosphorus(P) and zinc(Zn) in C. songaricum was high. The coefficient of variation of crude polysaccharide, ether extract, gallic acid, protocatechuic aldehyde, catechin, epicatechin, calcium(Ca), sodium(Na), magnesium(Mg), sulfur(S), iron(Fe), manganese(Mn), selenium(Se) and nickel(Ni) were all over 36%, indicating that the quality of C. songaricum was significantly affected by habitats. There were strong synergistic and weak antagonistic effects among the contents of the 8 active components, and complex antagonistic and synergistic effects among the contents of the 12 mineral elements. Principal component analysis revealed that crude polysaccharide, ursolic acid, catechin, epicatechin and total flavonoids could be used as the characteristic components to evaluate the quality of C. songaricum, and Na, copper(Cu), Mn and Ni were the characteristic elements to evaluate the quality of C. songaricum. In cluster ana-lysis, the second group with the main active components as cluster center had better quality in terms of the content of active substances, and the second group with the mineral elements as cluster center had higher utilization potential in the exploitation of mineral elements. This study could provide a basis for resource evaluation and breeding of excellent varieties of C. songaricum in different habitats, and provide a reference for cultivation and identification of C. songaricum.

Regulation of myocardial ischemia reperfusion injury signal pathway by flavonoid monomer / 中国中药杂志

Acute myocardial infarction seriously endangers the health of people due to its high morbidity and high mortality. Reperfusion strategy is the preferred treatment strategy for acute myocardial infarction. However, reperfusion may lead to additional heart damage, namely myocardial ischemia reperfusion injury(MIRI). Therefore, how to reduce myocardial ischemia reperfusion injury has become one of the urgent problems to be solved in cardiovascular disease. Traditional Chinese medicine(TCM) has the multi-component, multi-channel, and multi-target advantages in the treatment of MIRI, which offers new ideas in this aspect. TCM containing flavonoids has a variety of biological activities and plays a significant role in the treatment of MIRI, which has great research and development application value. TCM containing flavonoids can regulate multiple signaling pathways of MIRI, such as phosphatidylinositol 3 kinase/kinase B(PI3K/Akt) signaling pathway, Janus kinase/signal transducer and activator of transcriptions(JAK/STAT) signaling pathway, adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK) signaling pathway, mitogen-activated protein kinase(MAPK) signaling pathway, nuclear factor-erythroid 2-related factor 2/antioxidant response element(Nrf2/ARE) signaling pathway, nuclear factor kappa-B(NF-κB) signaling pathway, silent information regulator 1(Sirt1) signaling pathway, and Notch signaling pathway. It reduces MIRI by inhibiting calcium overload, improving energy metabolism, regulating autophagy, and inhibiting ferroptosis and apoptosis. Therefore, a review has been made based on the regulation of relative signaling pathways against MIRI by TCM containing flavonoids, thus providing theoretical support and potential therapeutic strategies for TCM to alleviate MIRI.

Three-dimensional multi-component analysis of Aurantii Fructus quality and research on influencing factors / 中国中药杂志

The present study explored the consistency of the content proportions of active components of Aurantii Fructus and analyzed the influencing factors based on three-dimensional multi-component analysis. A total of 839 Aurantii Fructus samples in 65 research articles were analyzed using the three-dimensional multi-component analysis mode. The content data of flavonoid components(naringin, hesperidin, neohesperidin, narirutin, and nobiletin), coumarin components(meranzin and gluconolactone), and alkaloid(synephrine) in 386 samples which met the criteria of 2020 edition of the Chinese Pharmacopoeia were extracted and adjusted to percentages, and the content ratios between components were calculated. The influencing factors of Aurantii Fructus quality were analyzed. The results showed content ratios of components as follows: neohesperidin∶naringin in the range of 0.4-1.2; narirutin∶naringin in the range of 0.02-0.16; hesperidin∶naringin in the range of 0.01-0.3; nobiletin∶naringin in the range of 0.000 588 3-0.069 68; synephrine∶naringin in the range of 0.02-0.042; gluconolactone∶naringin in the range of 0.001-0.01; meranzin∶naringin in the range of 0.000 4-0.035. The quality of Aurantii Fructus was closely related to the origin, variety, harvesting time, and processing method of medicinal materials. Harvesting time had a greater impact on the quality of Aurantii Fructus, and the origin and variety had a certain impact on the quality of Aurantii Fructus. The findings of this study indicated that the ratios between flavonoid components, flavonoids and coumarin components, and flavonoids and alkaloids fluctuated. The production base should optimize the varieties, harvesting period, and processing methods of Aurantii Fructus to provide a scientific basis for the production of high-quality Aurantii Fructus.

Effect of total flavonoids of buckwheat flower and leaf on myocardial cell apoptosis and Wnt/β-catenin/PPARγ pathway in arrhythmic rats / 中国中药杂志

This paper aimed to investigate the effect of total flavonoids of buckwheat flower and leaf on myocardial cell apoptosis and Wnt/β-catenin/peroxisome proliferator-activated receptor γ(PPARγ) pathway in arrhythmic rats. SD rats were randomly divided into a control group, a model group, a low-dose(20 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a medium-dose(40 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a high-dose(80 mg·kg~(-1)) group of total flavonoids of buckwheat flower and leaf, a propranolol hydrochloride(2 mg·kg~(-1)) group, with 12 rats in each group. Except the control group, rats in other groups were prepared as models of arrhythmia by sublingual injection of 1 mL·kg~(-1) of 0.002% aconitine. After grouping and intervention with drugs, the arrhythmia, myocardial cells apoptosis, myocardial tissue glutathione peroxidase(GSH-Px), catalase(CAT), malondialdehyde(MDA), serum interleukin-6(IL-6), prostaglandin E2(PGE2) levels, myocardial tissue apoptosis, and Wnt/β-catenin/PPARγ pathway-related protein expression of rats in each group were measured. As compared with the control group, the arrhythmia score, the number of ventricular premature beats, ventricular fibrillation duration, myocardial cell apoptosis rate, MDA levels in myocardial tissues, serum IL-6 and PGE2 levels, Bax in myocardial tissues, and Wnt1 and β-catenin protein expression levels increased significantly in the model group, whereas the GSH-Px and CAT levels, and Bcl-2 and PPARγ protein expression levels in myocardial tissues reduced significantly. As compared with the model group, the arrhythmia score, the number of ventricular premature beats, ventricular fibrillation duration, myocardial cell apoptosis rate, MDA leve in myocardial tissues, serum IL-6 and PGE2 levels, Bax in myocardial tissues, and Wnt1 and β-catenin protein expression levels reduced in the drug intervention groups, whereas the GSH-Px and CAT levels and Bcl-2 and PPARγ protein expression levels in myocardial tissues increased. The groups of total flavonoids of buckwheat flower and leaf were in a dose-dependent manner. There was no significant difference in the levels of each index in rats between the propranolol hydrochloride group and the high-dose group of total flavonoids of buckwheat flower and leaf. The total flavonoids of buckwheat flower and leaf inhibit the activation of Wnt/β-catenin pathway, up-regulate the expression of PPARγ, reduce oxidative stress and inflammatory damage in myocardial tissues of arrhythmic rats, reduce myocardial cell apoptosis, and improve the symptoms of arrhythmia in rats.

Anti-hyperuricemia activity and its mechanism of flavonoid extract from saffron floral bio-residues / 中国中药杂志

A hyperuricemic rat model induced by adenine and ethambutol was established to investigate the anti-hyperuricemia activity and its mechanism of the flavonoid extract from saffron floral bio-residues. Sixty-seven SD rats were randomly divided into control group, model group, positive control group, and flavonoid extract groups(with 3 doses), respectively, and each group contained 11 or 12 rats. The hyperuricemic model was established by continuous oral administration of adenine(100 mg·kg~(-1)) and ethambutol(250 mg·kg~(-1)) for 7 days. At the same time, the positive control group was given allopurinol(20 mg·kg~(-1) per day) and the flavonoid extract groups were given the flavonoid extract at doses of 340, 170 and 85 mg·kg~(-1) per day, respectively. On day 8, rat serum, liver, kidney, and intestinal tissues were collected, and the levels of uric acid in serum and tissue, the xanthine oxidase activities and antioxi-dant activities in serum and liver were evaluated, and the kidney histopathology was explored. In addition, an untargeted serum metabolomics study was performed. According to the results, the flavonoid extract effectively reduced the uric acid levels in serum, kidney and ileum and inhibited the xanthine oxidase activities and elevated the antioxidant activities of serum and liver in hyperuricemic rat. At the same time, it reduced the levels of inflammation factors in kidney and protected renal function. Moreover, 68 differential metabolites of hyperuricemic rats were screened and most of which were lipids and amino acids. The flavonoid extract significantly retrieved the levels of differential metabolites in hyperuricemic rats, such as SM(d18:1/20:0), PC[18:0/18:2(92,12Z)], palmitic acid and citrulline, possibly through the following three pathways, i.e., arginine biosynthesis, glycine, serine and threonine metabolism, and histidine metabolism. To sum up, the flavonoid extract of saffron floral bio-residues lowered the uric acid level, increased the antioxidant activity, and alleviated inflammatory symptoms of hyperuricemic rats, which may be related to its inhibition of xanthine oxidase activity and regulation of serum lipids and amino acids metabolism.

Mechanism of total flavonoids of Rhododendra simsii in alleviating ischemic brain injury / 中国中药杂志

This study explores the effect of total flavonoids of Rhododendra simsii(TFR) on middle cerebral artery occlusion(MCAO)-induced cerebral injury in rats and oxygen-glucose deprivation/reoxygenation(OGD/R) injury in PC12 cells and the underlying mechanism. The MCAO method was used to induce focal ischemic cerebral injury in rats. Male SD rats were randomized into sham group, model group, and TFR group. After MCAO, TFR(60 mg·kg~(-1)) was administered for 3 days. The content of tumor necrosis factor-α(TNF-α), interleukin-1(IL-1), and interleukin-6(IL-6) in serum was detected by enzyme-linked immunosorbent assay(ELISA). The pathological changes of brain tissue and cerebral infarction were observed based on hematoxylin and eosin(HE) staining and 2,3,5-triphenyltetrazolium chloride(TTC) staining. RT-qPCR and Western blot were used to detect the mRNA and protein levels of calcium release-activated calcium channel modulator 1(ORAI1), stromal interaction molecule 1(STIM1), stromal intera-ction molecule 2(STIM2), protein kinase B(PKB), and cysteinyl aspartate specific proteinase 3(caspase-3) in brain tissues. The OGD/R method was employed to induce injury in PC12 cells. Cells were randomized into the normal group, model group, gene silencing group, TFR(30 μg·mL~(-1)) group, and TFR(30 μg·mL~(-1))+gene overexpression plasmid group. Intracellular Ca~(2+) concentration and apoptosis rate of PC12 cells were measured by laser scanning confocal microscopy and flow cytometry. The effect of STIM-ORAI-regulated store-operated calcium entry(SOCE) pathway on TFR was explored based on gene silencing and gene overexpression techniques. The results showed that TFR significantly alleviated the histopathological damage of brains in MCAO rats after 3 days of admini-stration, reduced the contents of TNF-α, IL-1, and IL-6 in the serum, down-regulated the expression of ORAI1, STIM1, STIM2, and caspase-3 genes, and up-regulated the expression of PKB gene in brain tissues of MCAO rats. TFR significantly decreased OGD/R induced Ca~(2+) overload and apoptosis in PC12 cells. However, it induced TFR-like effect by ORAI1, STIM1 and STIM2 genes silencing. However, overexpression of these genes significantly blocked the effect of TFR in reducing Ca~(2+) overload and apoptosis in PC12 cells. In summary, in the early stage of focal cerebral ischemia-reperfusion injury and OGD/R-induced injury in PC12 cells TFR attenuates ischemic brain injury by inhibiting the STIM-ORAI-regulated SOCE pathway and reducing Ca~(2+) overload and inflammatory factor expression, and apoptosis.

Effect of processing method on chemical constituents of Rehmanniae Radix: based on UHPLC-LTQ-Orbitrap MS / 中国中药杂志

This study aims to explore the chemical composition of Rehmanniae Radix braised with mild fire and compare the effect of processing method on the chemical composition of Rehmanniae Radix. To be specific, ultra-high performance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS) was used to screen the chemical constituents of Rehmanniae Radix. The chemical constituents were identified based on the relative molecular weight and fragment ions, literature information, and Human Metabolome Database(HMDB). The ion peak area ratio of each component before and after processing was used as the index for the variation. SIMCA was employed to establish principal component analysis(PCA) and orthogonal partial least squares discriminant analysis(OPLS-DA) models of different processed products. According to the PCA plot, OPLS-DA plot, and VIP value, the differential components before and after the processing were screened out. The changes of the content of differential components with the processing method were analyzed. A total of 66 chemical components were identified: 57 of raw Rehmanniae Radix, 55 of steamed Rehmanniae Radix, 55 of wine-stewed Rehmanniae Radix, 51 of repeatedly steamed and sundried Rehmanniae Radix Praeparata, 62 of traditional bran-braised Rehmanniae Radix, and 63 of electric pot-braised Rehmanniae Radix. Among them, the 9 flavonoids of braised Rehmanniae Radix were from Citri Reticulatae Pericarpium. PCA suggested significant differences in the chemical composition of Rehmanniae Radix Praeparata prepared with different processing methods. OPLS-DA screened out 32 chemical components with VIP value >1 as the main differential components. Among the differential components, 9 were unique to braised Rehmanniae Radix(traditional bran-braised, electric pot-braised) and the degradation rate of the rest in braised(traditional bran-braised, electric pot-braised) or repeatedly steamed and sundried Rehmanniae Radix was higher than that in the steamed or wine-stewed products. The results indicated the chemical species and component content of Rehmanniae Radix changed significantly after the processing. The 32 components, such as rehmapicrogenin, martynoside, jionoside D, aeginetic acid, hesperidin, and naringin, were the most important compounds to distinguish different processed products of Rehmanniae Radix. The flavonoids introduced by Citri Reticulatae Pericarpium as excipient may be the important material basis for the effectiveness of braised Rehmanniae Radix compared with other processed products.

Cloning and functional analysis of flavanone 3-hydroxylase gene in Rhododendron hybridum Hort / 生物工程学报

Flavanone 3-hydroxylase (F3H) is a key enzyme in the synthesis of phycocyanidins. In this experiment, the petals of red Rhododendron hybridum Hort. at different developmental stages were used as experimental materials. The R. hybridum flavanone 3-hydroxylase (RhF3H) gene was cloned using reverse transcription PCR (RT-PCR) and rapid-amplification of cDNA ends (RACE) techniques, and bioinformatics analyses were performed. Petal RhF3H gene expression at different developmental stages were analyzed by using quantitative real-time polymerase chain reaction (qRT-PCR). A pET-28a-RhF3H prokaryotic expression vector was constructed for the preparation and purification of RhF3H protein. A pCAMBIA1302-RhF3H overexpression vector was constructed for genetic transformation in Arabidopsis thaliana by Agrobacterium-mediated method. The results showed that the R. hybridum Hort. RhF3H gene is 1 245 bp long, with an open reading frame of 1 092 bp, encoding 363 amino acids. It contains a Fe2+ binding motif and a 2-ketoglutarate binding motif of the dioxygenase superfamily. Phylogenetic analysis showed that the R. hybridum RhF3H protein is most closely related to the Vaccinium corymbosum F3H protein. qRT-PCR analysis showed that the expression level of the red R. hybridum RhF3H gene tended to increase and then decrease in the petals at different developmental stages, with the highest expression at middle opening stage. The results of the prokaryotic expression showed that the size of the induced protein of the constructed prokaryotic expression vector pET-28a-RhF3H was about 40 kDa, which was similar to the theoretical value. Transgenic RhF3H Arabidopsis thaliana plants were successfully obtained, and PCR identification and β-glucuronidase (GUS) staining demonstrated that the RhF3H gene was integrated into the genome of A. thaliana plants. qRT-PCR, total flavonoid and anthocyanin contentanalysis showed that RhF3H was significantly higher expressed in the transgenic A. thaliana relative to that of the wild type, and its total flavonoid and anthocyanin content were significantly increased. This study provides a theoretical basis for investigating the function of RhF3H gene, as well as for studying the molecular mechanism of flower color in R. simsiib Planch.

Phenylpropanoid pathway in plants and its role in response to heavy metal stress: a review / 生物工程学报

Phenylpropanoid metabolic pathway is one of the most important secondary metabolic pathways in plants. It directly or indirectly plays an antioxidant role in plant resistance to heavy metal stress, and can improve the absorption and stress tolerance of plants to heavy metal ions. In this paper, the core reactions and key enzymes of the phenylpropanoid metabolic pathway were summarized, and the biosynthetic processes of key metabolites such as lignin, flavonoids and proanthocyanidins and relevant mechanisms were analyzed. Based on this, the mechanisms of key products of phenylpropanoid metabolic pathway in response to heavy metal stress were discussed. The perspectives on the involvement of phenylpropanoid metabolism in plant defense against heavy metal stress provides a theoretical basis for improving the phytoremediation efficiency of heavy metal polluted environment.

Geranylated or prenylated flavonoids from Cajanus volubilis / 中国天然药物

Five new flavonoid derivatives, cajavolubones A-E (1-5), along with six known analogues (6-11) were isolated from Cajanus volubilis, and their structures were elucidated by spectroscopic analysis and quantum chemical calculations. Cajavolubones A and B (1 and 2) were identified as two geranylated chalcones. Cajavolubone C (3) was a prenylated flavone, while cajavolubones D and E (4 and 5) were two prenylated isoflavanones. Compounds 3, 8, 9 and 11 displayed cytotoxicity against HCT-116 cancer cell line.