Effect of Dioscorea villosa extract and the phytoestrogen diosgenin on ovariectomized mice with zymosan-induced arthritis

Abstract Humans are exposed to natural compounds such as phytoestrogens primarily through diet and supplements. These compounds promote health by alleviating the symptoms and illnesses associated with menopause and arthritis. Diosgenin (DSG) occurs naturally in plants such as Dioscorea villosa (DV) and binds to estrogen receptors, so it may have similar effects to this hormone, including against arthritis. Thus, we investigated the effect of chronic treatment with dry extract of DV and its phytoestrogen DSG on ovariectomized mice with arthritis. We found that dry extract of Dioscorea villosa (DV) contains the phytoestrogen diosgenin (DSG) in its composition. Furthermore, arthritic mice treated with DV and DSG showed reduced neutrophil accumulation in the articular cartilage. Also, the dry extract of DV administered orally (v.o) did not alter the leukocyte count in the joints or promote changes in the reproductive tract. However, DSG altered these parameters, with possible beneficial effects by reducing symptoms related to reproductive aging. Thus, oral treatment with dry extract of DV and subcutaneous (s.c) treatment with DSG showed promise by acting against inflammation caused by arthritis and reducing symptoms in the reproductive tract due to menopause.

Research progress of nitrobenzoyl sesquiterpenoids as marine characteristic natural products / 药学学报

Sesquiterpenoids are widely found in nature, while nitrobenzoyl sesquiterpenoids are relatively rare. Twelve natural nitrobenzoyl sesquiterpenoids were all derived from marine Aspergillus fungi, which are typical natural products with marine characteristics. These natural products exhibit good antitumor, antiviral, and inhibition of osteoclast differentiation activity, especially in the treatment of osteoclast-related diseases, showing good medicinal development value. This article reviews the natural product sources, chemical structure, chemical synthesis, biosynthesis, bioactivity, and pharmacological mechanisms of nitrobenzoyl sesquiterpenoids and predicts and discusses their absorption, distribution, metabolism, excretion, toxicity (ADME/T), and drug-likeness, providing a comprehensive understanding of the natural products of nitrobenzoyl sesquiterpenoids from marine sources and their potential for pharmaceutical development.

Traditional Uses and Anticancer Potential of the Combretum Genus: A Literature Review

Background: Cancer incidence is increasing annually in all countries. So, it is nowadays a great burden for the different nations of the world. Research for new therapeutics is becoming an urgent need, particularly for intractable and chemoresistant cancer cases. The solutions can still be found by investigating natural products which are recognized as promising sources of bioactive compounds with a potential for the discovery of new preventive and therapeutic anticancer agents. Methodology: The present work used databases such as Pubmed, Science Direct and Google scholar to investigate the ethnobotanical uses of some Combretum species in the literature. It also allowed us to summarize some pharmacological studies on Combretum species. Results: This review gathers all available traditional uses and cytotoxicity studies of Combretum species in the literature. Special focus is given to pharmacological studies highlighting isolated potential anticancer molecules. These molecules present potent cytotoxic effect on various cancer cell lines and may contribute to improving the health of people suffering from various cancer diseases. Conclusion: The Combretum species are widely used in folk medicine for the treatment of several pathologies including cancers. This study is of fundamental importance in highlighting Combretum species as a potential source for research of new anticancer compounds.

Chiral separation methods and the applications in the study of chiral components of traditional Chinese medicines / 药学学报

Chirality is one of the fundamental properties of nature, and most of the important molecules in living organisms contain chiral structures. The efficacy and safety of drugs are often closely related to the chiral structure of compounds, however, there are relatively more studies on synthetic characterization, pharmacology, and toxicology of chiral small molecule chemical drugs, but relatively less studies on chiral compounds contained in natural drugs such as traditional Chinese medicines. Chiral separation, as the basis of chiral research, has a pivotal position in the study of chiral compounds. In this paper, we systematically describe the separation methods of chiral compounds from the classification of chiral splitting methods based on chromatographic and non-chromatographic methods, as well as chromatographic packing materials, chiral additives and chiral derivatization, and review the chiral compounds in natural drugs such as traditional Chinese medicines reported in the past ten years, in order to provide references for the splitting and evaluating the activity of chiral compounds, and the improvement of quality standards of traditional Chinese medicines.

Advances in online two-dimensional liquid chromatography for natural product screening / 药学学报

As a treasure resource of novel drug lead compounds, how to rapidly and high-efficiently screen and isolate active components from natural products is critical. Thanks to its high resolution, high automation and flexible integration, online two-dimensional liquid chromatography has great potential for screening active ingredients from complex matrices by integrating a highly specific bio-recognition process into a two-dimensional liquid chromatography system before, on or after the column separation. This review comprehensively summarized recent developments, applications and shortcomings of online two-dimensional liquid chromatography for natural product screening from different integration modes, including pre-column, on-column and post-column screening methods.

Rhodojaponin VI indirectly targets Cav2.2 channels via N-ethylmaleimide-sensitive fusion protein to alleviate neuropathic pain

Neuropathic pain is a chronic disease that severely afflicts the life and emotional status of patients, but currently available treatments are often ineffective. Novel therapeutic targets for the alleviation of neuropathic pain are urgently needed. Rhodojaponin VI, a grayanotoxin from Rhododendron molle, showed remarkable antinociceptive efficacy in models of neuropathic pain, but its biotargets and mechanisms are unknown. Given the reversible action of rhodojaponin VI and the narrow range over which its structure can be modified, we perforwmed thermal proteome profiling of the rat dorsal root ganglion to determine the protein target of rhodojaponin VI. N-Ethylmaleimide-sensitive fusion (NSF) was confirmed as the key target of rhodojaponin VI through biological and biophysical experiments. Functional validation showed for the first time that NSF facilitated trafficking of the Cav2.2 channel to induce an increase in Ca2+ current intensity, whereas rhodojaponin VI reversed the effects of NSF. In conclusion, rhodojaponin VI represents a unique class of analgesic natural products targeting Cav2.2 channels via NSF.

Insights into the biosynthesis of septacidin l-heptosamine moiety unveils a VOC family sugar epimerase

l-Heptopyranoses are important components of bacterial polysaccharides and biological active secondary metabolites like septacidin (SEP), which represents a group of nucleoside antibiotics with antitumor, antifungal, and pain-relief activities. However, little is known about the formation mechanisms of those l-heptose moieties. In this study, we deciphered the biosynthetic pathway of the l,l-gluco-heptosamine moiety in SEPs by functional characterizing four genes and proposed that SepI initiates the process by oxidizing the 4'-hydroxyl of l-glycero-α-d-manno-heptose moiety of SEP-328 ( 2) to a keto group. Subsequently, SepJ (C5 epimerase) and SepA (C3 epimerase) shape the 4'-keto-l-heptopyranose moiety by sequential epimerization reactions. At the last step, an aminotransferase SepG installs the 4'-amino group of the l,l-gluco-heptosamine moiety to generate SEP-327 ( 3). An interesting phenomenon is that the SEP intermediates with 4'-keto-l-heptopyranose moieties exist as special bicyclic sugars with hemiacetal-hemiketal structures. Notably, l-pyranose is usually converted from d-pyranose by bifunctional C3/C5 epimerase. SepA is an unprecedented monofunctional l-pyranose C3 epimerase. Further in silico and experimental studies revealed that it represents an overlooked metal dependent-sugar epimerase family bearing vicinal oxygen chelate (VOC) architecture.

Advances in gene editing and natural product synthesis of Rhodotorula toruloides / 生物工程学报

Rhodotorula toruloides is a non-conventional red yeast that can synthesize various carotenoids and lipids. It can utilize a variety of cost-effective raw materials, tolerate and assimilate toxic inhibitors in lignocellulosic hydrolysate. At present, it is widely investigated for the production of microbial lipids, terpenes, high-value enzymes, sugar alcohols and polyketides. Given its broad industrial application prospects, researchers have carried out multi-dimensional theoretical and technological exploration, including research on genomics, transcriptomics, proteomics and genetic operation platform. Here we review the recent progress in metabolic engineering and natural product synthesis of R. toruloides, and prospect the challenges and possible solutions in the construction of R. toruloides cell factory.

Potential of natural products containing 3-acyl tetramic acid as antibacterial precursors / 药学学报

The natural products containing 3-acyl tetramic acid units have a large number of complex and diverse structures, showing a variety of biological activities such as antibacterial, antiviral, anti-tumor and so on, especially antibacterial activity which are regarded as a potential reservoir of new antibiotics. In this paper, the antibacterial activities of various natural products containing 3-acyl tetramic acids and the new research hotspots and directions are reviewed.

Label-free target identification for natural products based on proteomics / 药学学报

Target identification and verification of natural products is an important and challenging work in the field of chemical biology. It is also an important job for researchers to apply chemical proteomics technology to biomedicine in order to identify target proteins of natural products. Target identification is critical to understanding its mechanisms and developing natural products as molecular probes and potential therapeutic drugs. Traditional approaches of small molecule target identification based on affinity have been shown to be successful, such as click-chemical probes, radioisotope labeling or photosensitized small-molecule probes. Nevertheless, these technologies require purified candidate target proteins, and modified small molecules with probes or linkers, such as adding agarose beads, biotin labels, fluorescent labeling or photo-affinity labeling. Many structure-activity relationship studies should be performed to ensure that the addition of small molecule labels undisturbed the original biological activity of the small molecules. Unfortunately, all these modifications are likely to alter their biological activity or binding specificity. To overcome the bottleneck of "target recognition", researchers have developed a series of new techniques for unmodified drug target identification. In this article, we reviewed the target identification techniques of natural product without structural modification in order to provide reference for the development of natural products.

Research progress of bacterial biofilm eradication agents based on modifications of natural products / 药学学报

Bacterial biofilm widely exists in all kinds of bacteria, and is related to about 80 percent of bacterial infections. It is one of the main reasons for bacterial tolerance and resistance to existing antibiotics. Therefore, there is unmet clinical need for new anti-biofilm drugs. At present, there are three kinds of anti-biofilm agents under research, including biofilm inhibitors, biofilm dispersal agents and biofilm eradication agents. Among them, the biofilm eradication agent is unique, which can not only kill bacteria in biofilm but also eliminate biofilm as a monotherapy. Based on modifications of natural products with antibacterial activity, a variety of compounds with biofilm eradicating activities have been obtained, such as, acyldepsipeptides, pyrrolomycins, halogenated phenazines and halogenated 8-hydroxyquinolines. In this review, we summarize several major biofilm eradication agents above according to their structures and mechanisms.

Metodología de pesquisa primaria de actividad antidengue a partir de productos naturales / Methodology for primary screening of antidengue activity based on natural products

Introducción: El virus dengue, transmitido por mosquitos del género Aedes ha reemergido en los últimos años produciendo la enfermedad transmitida por artrópodos con mayor prevalencia en humanos, y no existe una terapia antiviral específica ni vacunas, para su tratamiento y prevención. Ello ha motivado la búsqueda de productos y compuestos naturales con actividad antiviral, lo cual trae consigo la necesidad de establecer un sistema de evaluación de productos naturales y sintéticos mediante una metodología de pesquisa rápida in vitro. Objetivo: Proponer un sistema de pesquisa primaria de actividad antiviral contra el virus dengue basado en células. Métodos: Se utilizaron como fuentes primarias de información trabajos publicados en revistas nacionales e internacionales registradas en las bases de datos SciELO o PubMed. Los ejemplos seleccionados en las figuras y tabla proceden de las publicaciones conjuntas del Grupo de Virología de la Facultad de Biología de la Universidad de La Habana y del Laboratorio de Arbovirus del Instituto de Medicina Tropical Pedro Kourí. Información, análisis y síntesis: Se presentan las principales metodologías basadas en células, y se enfatiza en aquellas asumidas por nuestro grupo (evaluación de la citotoxicidad y el ensayo primario de actividad antiviral). Se muestra el algoritmo de evaluación de un producto. La metodología descrita ha permitido poner en marcha un programa de búsqueda de fármacos antidengue, teniendo en cuenta los criterios de la evaluación de la eficacia antiviral y la toxicidad, para realizar un estudio posterior de mecanismo de acción de los diferentes compuestos o productos evaluados.

Introduction: Dengue virus, transmitted by Aedes specie mosquitos, has re-emerged in the last years causing the arthropod-borne disease with higher prevalence in humans, to which there is no specific antiviral therapy or vaccine for its treatment and prevention. This has motivated the search for natural-based products with antiviral activity, which implies the need to establish an evaluation system of natural and synthetic products through a rapid in vitro screening methodology. Objective: To propose a primary screening cell-based antiviral activity system against dengue virus. Methods: Papers published in national and international journals indexed in SciELO or PubMed were used as primary sources of information. The examples selected in the figures and table were retrieved from the joint publications of the Virology Group of the School of Biology of the University of Havana and the Arbovirus Laboratory of the Institute of Tropical Medicine Pedro Kourí. Information, Analysis and Synthesis: The main cell-based methodologies are presented, with emphasis on those assumed by our research group (evaluation of cytotoxicity and the primary antiviral activity assay). The algorithm for product evaluation is presented. The methodology described has allowed initiating a search program for antidengue drugs, taking into account the criteria for evaluating antiviral efficacy and toxicity, in order to carry out a subsequent study on the mechanisms of action of the different compounds or products evaluated.

High-intensity resistance exercise and Schinus terenbinthifolius supplementation attenuate oxidative stress and muscle damage biomarkers / El ejercicio de resistencia de alta intensidad y la suplementación con Schinus terenbinthifolius atenúan los biomarcadores del estrés oxidativo y daño muscular

SUMMARY: High-intensity physical exercises can cause oxidative stress and muscle damage. Several medicinal plants have been used as antioxidant and anti-inflammatory agents. The present study evaluated high-intensity resistance exercise (HIRE) associated with Schinus Terebentifholius ethanolic extract (EE) on oxidative parameters and muscle damage in Wistar rats. Animals were divided into 04 groups (n=10/group): 1. Control (CG) - animals that did not undergo HIRE and were treated with vehicle (distilled water, orally); 2. Acute exercise (AE) - animals submitted to acute exercise session; 3. Exercise + vehicle (EV) - animals that underwent HIRE and were treated with vehicle and 4. Exercise + extract (EX) animals administered with Schinus terebenthifolius EE (100mg/Kg, orally) and submitted to the exercise session. Schinus terebenthifolius EE showed high in vitro antioxidant activity (13.88 ± 0.36 mg/mL). Before the experimental period, lactate was measured at pre and post moments of AE (p<0.0001) and EX (p<0.0001) groups. After the acute session, the following were evaluated: oxidative stress {malondialdehyde (MDA), sulfhydryl groups (SH) and ferric reducing antioxidant power (FRAP)}, muscle damage (creatine kinase (CK) and lactate dehydrogenase (LDH)), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In the in vivo analyses of the EX group compared to AE and EV groups, respectively: hepatic (MDA: p<0.0001 and SH: p=0.0033, in both; FRAP: p=0.0011 and p=0.0047), muscle (MDA, SH and FRAP: p<0.0001, in both; CK: p=0.0001 and p<0.0001; LDH: p<0.0001, in both), serum levels (MDA: p=0.0003, p=0.0012, SH: p=0.0056, p=0.0200, FRAP: p=0.0017 and p=0.0165) were significant. There was no significant difference in ALT and AST markers. It could be concluded that Schinus terebenthifolius EE associated with HIRE attenuated oxidative stress and muscle damage in rats.

RESUMEN: Los ejercicios físicos de alta intensidad pueden causar estrés oxidativo y daño muscular. Varias plantas medicinales se han utilizado como agentes antioxidantes y antiinflamatorios. El presente estudio evaluó el ejercicio de resistencia de alta intensidad (HIRE) asociado con el extracto etanólico (EE) de Schinus terebentifholius sobre los parámetros oxidativos y el daño muscular en ratas Wistar. Los animales se dividieron en 4 grupos (n=10/grupo): 1. Control (GC) - animales que no se sometieron a HIRE y fueron tratados con vehículo (agua destilada, por vía oral); 2. Ejercicio agudo (AE) - animales sometidos a sesión de ejercicio agudo; 3. Ejercicio + vehículo (EV) - animales que se sometieron a HIRE y fueron tratados con vehículo y 4. Ejercicio + extracto (EX) animales administrados con Schinus terebenthifolius EE (100 mg/kg, por vía oral) y sometidos a la sesión de ejercicio. Schinus terebenthifolius EE mostró una alta actividad antioxidante in vitro (13,88 ± 0,36 mg/mL). Antes del período experimental, se midió el lactato en los momentos pre y post de los grupos AE (p<0,0001) y EX (p<0,0001). Tras la sesión aguda, se evaluaron: el estrés oxidativo malondialdehído (MDA), grupos sulfhidrilo (SH) y poder antioxidante reductor férrico (FRAP), daño muscular (creatina quinasa (CK) y lactato deshidrogenasa (LDH)), alanina aminotransferasa (ALT) y aspartato aminotransferasa (AST). En los análisis in vivo del grupo EX frente a los grupos AE y EV, respectivamente: hepático (MDA: p<0,0001 y SH: p=0,0033, en ambos; FRAP: p=0,0011 y p=0,0047), muscular (MDA, SH y FRAP: p<0,0001, en ambos; CK: p=0,0001 y p<0,0001; LDH: p<0,0001, en ambos), niveles séricos (MDA: p=0,0003, p=0,0012, SH: p=0,0056, p=0,0200, FRAP: p=0,0017 y p=0,0165) fueron significativas. No hubo diferencia significativa en los marcadores ALT y AST. Se podría concluir que Schinus terebenthifolius EE asociado con HIRE atenuó el estrés oxidativo y el daño muscular en ratas.

Antibacterial and anti-biofilm potential of Plectranthus amboinicus (Lour) Spreng essential oil and Carvacrol against Staphylococcus aureus and Escherichia coli / Potencial antibacteriano e anti-biofilme do óleo essencial de Plectranthus amboinicus (Lour) Spreng e carvacrol frente a Staphylococcus aureus e Escherichia coli

Introduction: Staphylococcus aureus and Escherichia coli are pathogens that cause chronic infections due to antibiotic resistance mechanisms and their ability to adhere to surfaces and to form biofilms. The search for new agents from natural resources to counter microbial biofilms is an urgent priority in healthcare. Objetive: chemical composition, antibacterial and anti-biofilm activity of Plectranthus amboinicus essential oil (PAEO) and carvacrol were investigated against E. coli and S. aureus. Methodology: PAEO was chemically analyzed using gas chromatography coupled to a mass spectrometer. Antimicrobial activity was assessed by the disc diffusion method and broth microdilution method to determine minimum inhibitory concentrations (MICs). Antibiofilm activity was investigated using 96-well plates with a crystal violet assay. Results: carvacrol (85.25%) was the major component of PAEO. The disc diffusion test confirmed the ability of PAEO and carvacrol in inhibiting bacteria in their planktonic form. The MICs of PAEO against S. aureus and E. coli were 0.31 and 1.25%, respectively, with bactericidal effect. Carvacrol demonstrated a significant antibacterial property (MIC = 0.31%), exhibiting bacteriostatic effects against S. aureus and bactericidal effects against E. coli. Carvacrol considerably inhibited E. coli biofilm formations (58.9%). Moreover, carvacrol inactivated the mature biofilms. Conclusion: the data obtained are promising, and facilitates the development of new therapeutic alternatives. These results indicate the potential of carvacrol in treating diseases caused by E. coli and S. aureus

Introdução: Escherichia coli e Staphylococcus aureus são patógenos que podem causar infecções persistentes devido aos mecanismos de resistência e à sua capacidade de aderir e formar biofilme. A busca por novos agentes a partir de recursos naturais para combater o biofilme é uma prioridade na área da saúde. Objetivo: a composição química, a atividade antibacteriana e anti-biofilme do óleo essencial de Plectranthus amboinicus (PAEO) e do carvacrol foram investigadas frente a S. aureus e E. coli. Metodologia: a análise química do PAEO foi realizada por cromatografia gasosa acoplada a espectrômetro de massa. A atividade antimicrobiana foi avaliada por difusão em disco e microdiluição em caldo para determinar as concentrações inibitórias mínimas (CIMs). As atividades do anti-biofilme foram investigadas usando placas de 96 poços pelo ensaio de cristal violeta. Resultados: o carvacrol (85,25%) foi o principal componente do PAEO. A capacidade do PAEO e do carvacrol para inibir bactérias planctônica foi confirmada por difusão em disco. A CIM do PAEO para S. aureus e E. coli foi de 0,31 e 1,25%, respectivamente, com efeito bactericida. O carvacrol demonstrou uma propriedade antibacteriana significativa (CIM=0,31%), exibindo efeito bacteriostático frente a S. aureus e efeito bactericida para E. coli. O carvacrol inibiu significativamente a formação de biofilme de E. coli (58,9%) e promoveu a desestabilização do biofilme maduro. Conclusão: os dados obtidos são promissores, possibilitando o desenvolvimento de novas alternativas terapêuticas e revelam a potencialidade do carvacrol como fonte para o tratamento de doenças causadas por E. coli e S. aureus.

Phytochemical screening and evaluation of the toxic potential of ethanolic extract and fractions of Ageratum fastigiatum / Triagem fitoquímica e avaliação do potencial tóxico do extrato etanólico e frações de Ageratum fastigiatum / Cribado fitoquímico y evaluación del potencial tóxico del extracto etanólico y fracciones de Ageratum fastigiatum

SUMMARY Introduction: Ethanolic and hydroalcoholic extracts of Ageratum fastigiatum are used in folk medicine as anti-inflammatory and analgesic agents. Aim: To evaluate toxicity in Artemia salina and in the cells of the connective tissue of mice (L929). Methodology: The extract was partitioned and its hexane, dichloromethane and hydroalcoholic phases were submitted to the same test. The phytochemical screening of the phases of the extract was performed using tests aimed at the detection of secondary metabolites and GC-MS. Regarding A. salina, the hydroalcoholic phase exhibited the highest toxicity (LC50, 1.33 mg/mL) and the crude ethanolic extract was the least toxic (LC50, 4.81 mg/mL). In the assay of L929 cells, the dichloromethane phase was the most toxic (95.48% reduction in cell viability; LC50, 11.39 µg/mL), while the hydroalcoholic phase was the least toxic (cell death percentage, 55.67-19.38 %; LC50, 174.20 µg/mL). Result: The phytochemical study indicated the presence of alkaloids, coumarins, saponins, triterpenes/steroids and tannins. The GC-MS analysis identified the presence of terpenoids and a lycopsamine derivative (a pyrrolizidine alkaloid). Conclusion: These results suggest that the ethanolic extract of A. fastigiatum had constituents (i.e., phenolic compounds) that corroborate its use in folk medicine as an anti-inflammatory agent. However, the toxicity detected and the presence of 3'-acetyl lycopsamine (a chemotaxonomic marker of the genus that is hepatotoxic) indicates that this medicinal plant should be used with caution.

RESUMO Introdução: Os extratos etanólico e hidroalcoólico de Ageratum fastigiatum são usados na medicina popular como agentes antiinflamatório e analgésico. Objetivo: Avalidar quanto à sua toxicidade em Artemia salina e nas células do tecido conjuntivo de camundongos (L929). Metodologia: O extrato foi particionado e suas fases hexânica, diclorometânica e hidroalcoólica foram submetidas ao mesmo teste. A triagem fitoquímica das fases do extrato foi realizada por meio de testes visando a detecção de classes de metabólitos secundários e GC-MS. Resultados: Em relação a A. salina, a fase hidroalcoólica apresentou a maior toxicidade (CL50, 1,33 mg/mL) e o extrato etanólico bruto foi o menos tóxico (CL50_ 4,81 mg/mL). No ensaio de células L929, a fase de diclorometânica foi a mais tóxica (95,48% de redução na viabilidade celular; LC50, 11,39 µg/mL), enquanto a fase hidroalcoólica foi a menos tóxica (porcentagem de morte celular, 55,67-19,38 %; LC50, 174,20 µg/mL). O estudo fitoquímico indicou a provável presença de alcalóides, cumarinas, saponinas, triterpenos/ esteróides e taninos. A análise por GC-MS identificou a presença de terpenóides e um derivado de licopsamina (alcalóide pirrolizidínico). Conclusão: Esses resultados sugerem que o extrato etanólico de A. fastigiatum possui constituintes (ou seja, compostos fenólicos) que corroboram seu uso na medicina popular como agente antiinflamatório. No entanto, a toxicidade detectada e a presença da 3'-acetil licopsamina (um marcador quimiotaxonômico do gênero, que é hepatotóxico) indicam que essa planta medicinal deve ser usada com cautela.

RESUMEN Introducción: Los extractos etanólico e hidroalcohólico de Ageratum fastigiatum se utilizan en la medicina popular como agentes antiinflamatorios y analgésicos. Objetivo: Evaluar la toxicidad en artemia salina y en las células del tejido conectivo de ratones (L929). Metodología: El extracto se fraccionó y se sometieron a la misma prueba sus fases hexano, diclorometano e hidroalcohólica. El tamizaje fitoquímico de las fases del extracto se realizó mediante pruebas dirigidas a la detección de metabolitos secundarios y GC-MS. En cuanto a A. salina, la fase hidroalcohólica presentó la mayor toxicidad (CL50, 1,33 mg/mL) y el extracto etanólico crudo fue el menos tóxico (CL50, 4,81 mg/mL). En el ensayo de células L929, la fase de diclorometano fue la más tóxica (95,48% de reducción de la viabilidad celular; CL50, 11,39 µg/mL), mientras que la fase hidroalcohólica fue la menos tóxica (porcentaje de muerte celular, 55,67-19,38 %; CL50, 174,20 µg/mL). Resultado: El estudio fitoquímico indicó la probable presencia de alcaloides, cumarinas, saponinas, triterpenos/esteroides y taninos. El análisis GC-MS identificó la presencia de terpenoides y un derivado de licopsamina (un alcaloide de pirrolizidina). Conclusión: Estos resultados sugieren que el extracto etanólico de A. fastigiatum tenía constituyentes (es decir, compuestos fenólicos) que corroboran su uso en la medicina popular como agente antiinflamatorio. Sin embargo, la toxicidad detectada y la presencia de 3'-acetil licopsamina (un marcador quimiotaxonómico del género que es hepatotóxico) indica que esta planta medicinal debe utilizarse con precaución.

Megastigmanes from an aqueous extract of Uncaria rhynchophylla / 药学学报

Five new megastigmanes (1-5) were isolated from a decoction of Uncaria rhynchophylla by separation techniques of column chromatography using a combination of multiple stationary phases, including macroporous adsorbent resin, MCI resin, silica gel, Sephadex LH-20, and Toyopearl HW-40F, and reversed phase HPLC. Their structures were characterized by spectroscopic data analysis of HR-ESI-MS, NMR, and CD, in combination with Mosher's mothed as well as ECD and NMR calculations. The new compounds were named uncarphyllonone A (1), uncarphyllonols A (2) and B (3), and uncarphabscisic acids A (4) and B (5). Although the structures of 3 and 4 were previously reported, the reported NMR spectroscopic data were incorrect or do not support the assigned structures in literatures. This is also the first report of discovery of new megastigmane natural products from the Uncaria genus.

Progress of discovery of molecular glues from natural products and their derivatives / 药学学报

Molecular glues are a class of small molecules that induce the formation of protein-protein interactions to confer new biological function or therapeutic effects. As a unique pharmacological modality, molecular glues could target proteins without druggable binding pockets. It exhibits a variety of functions, including regulating signal transduction, stabilization or degradation of targeted proteins, through sticking different proteins together. This review will summarize the development and current status of molecular glues derived from natural products and analogs by illustrating the discovery and interaction mechanism. We hope to present a systematic view, provide valuable clues for researchers and encourage them to explore more efficient and rational molecular glue discovery strategies.

Research progress of natural products for the treatment of hyperuricemia and gout / 药学学报

Although current synthetic anti-gout drugs have significant therapeutic effects in reducing serum uric acid levels, they have serious side effects such as allergic reactions and liver and kidney damage. Natural products with a wide range of uric acid-lowering and high safety have played a critical role in anti-gout drug discovery and development. This paper reviews the natural products with uric acid-lowering or anti-gout pharmacological effects and the investigation on their mechanisms of action, to provide information for drug discovery and development.

A clickable photoaffinity probe of betulinic acid identifies tropomyosin as a target

Target identification of bioactive compounds is important for understanding their mechanisms of action and provides critical insights into their therapeutic utility. While it remains a challenge, unbiased chemoproteomics strategy using clickable photoaffinity probes is a useful and validated approach for target identification. One major limitation of this approach is the efficient synthesis of appropriately substituted clickable photoaffinity probes. Herein, we describe an efficient and consistent method to prepare such probes. We further employed this method to prepare a highly stereo-congested probe based on naturally occurring triterpenoid betulinic acid. With this photoaffinity probe, we identified tropomyosin as a novel target for betulinic acid that can account for the unique biological phenotype on cellular cytoskeleton induced by betulinic acid.

Promising natural lysine specific demethylase 1 inhibitors for cancer treatment: advances and outlooks / 中国天然药物

Lysine specific demethylase 1 (LSD1), a transcriptional corepressor or coactivator that serves as a demethylase of histone 3 lysine 4 and 9, has become a potential therapeutic target for cancer therapy. LSD1 mediates many cellular signaling pathways and regulates cancer cell proliferation, invasion, migration, and differentiation. Recent research has focused on the exploration of its pharmacological inhibitors. Natural products are a major source of compounds with abundant scaffold diversity and structural complexity, which have made a major contribution to drug discovery, particularly anticancer agents. In this review, we briefly highlight recent advances in natural LSD1 inhibitors over the past decade. We present a comprehensive review on their discovery and identification process, natural plant sources, chemical structures, anticancer effects, and structure-activity relationships, and finally provide our perspective on the development of novel natural LSD1 inhibitors for cancer therapy.