Research progress on Rhododendron molle in treatment of rheumatoid arthritis / 中国中药杂志

Rheumatoid arthritis(RA), as a chronic autoimmune disease, has a high incidence and disability rate, causing significant suffering to patients. Due to its complex pathogenesis, it has not been fully elucidated to date, and its treatment remains a challenging problem in the medical field. Although western medicine treatment options have certain efficacy, they require prolonged use and are expensive. Additionally, they carry risks of multiple infections and adverse reactions like malignancies. The Chinese herbal medicine Rhododendron molle is commonly used in folk medicine for its properties of dispelling wind, removing dampness, calming nerves, and alleviating pain in the treatment of diseases like rheumatic bone diseases. In recent years, modern clinical and pharmacological studies have shown that the diterpenoids in R. molle are effective components, exhibiting immune-regulatory, anti-inflammatory, and analgesic effects. This makes it a promising candidate for treating RA with a broad range of potential applications. However, R. molle has certain toxic properties that hinder its clinical application and lead to the wastage of its resources. This study reviewed recent research progress on the mechanism of R. molle in preventing and treating RA, focusing on its chemical components, anti-inflammatory and analgesic properties and summarized the adverse reactions associated with R. molle, aiming to offer new ideas for finding natural remedies for RA and methods to reduce toxicity while enhancing the effectiveness of R. molle. The study seeks to clarify the safety and efficacy of R. molle and its extracts, providing a theoretical basis for its application prospects and further promoting the development and utilization of R. molle resources.

Meroterpenoids from Rhododendron nivale / 中国中药杂志

To elucidate the chemical material basis of Rhododendron nivale, this study comprehensively used various chromatographic techniques to isolate and obtain five new meroterpenoid enantiomers(1a/1b-5a/5b) from the ethyl acetate extract of R. nivale. A variety of spectral analytical methods, such as high-resolution mass spectrometry(HRMS), nuclear magnetic resonance spectroscopy(NMR), and infrared(IR) spectrum, were used to evaluate the structure, combined with the measurement and calculation of electronic circular dichroism(ECD). The new compounds 1a/1b-4a/4b were named as(±)-nivalones A-B(1a/1b-2a/2b) and(±)-nivalnoids C-D(3a/3b-4a/4b), along with one known enantiomer(±)-anthoponoid G(5a/5b). Human neuroblastoma cells(SH-SY5Y cells) induced by hydrogen peroxide(H_2O_2) were used as oxidative stress models to evaluate the protective activity of the isolated compounds against oxidative damage to nerve cells. It was found that compounds 2a and 3a had a certain protective effect on nerve cells against H_2O_2-induced oxidative damage at concentrations of 50 μmol·L~(-1), which increased the cell survival rate from 44.02%±2.30% to 67.82%±1.12% and 62.20%±1.87%, respectively. Other compounds did not show a significant ability to protect cells from oxidative damage. These findings enrich the chemical constituents of R. nivale and provide valuable information for identifying the structure of its meroterpenoids.

A new lignan glucoside from stems and branches of Rhododendron ovatum / 中国中药杂志

Ten lignans were isolated from the ethanol extract of stems and branches of Rhododendron ovatum through column chromatography over silica gel, ODS, Sephadex LH-20, and MCI-gel resin and semi-preparative RP-HPLC. The structures of all compounds were elucidated by extensive spectroscopic data analysis(UV, IR, HR-ESI-MS, ECD and NMR) as(-)-4-epi-lyoniresinol-9'-O-α-L-rhamnopyranoside(1),(+)-lyoniresinol-3α-O-α-L-rhamnopyranoside(2),(+)-5'-methoxyisolariciresinol-9'-O-α-L-rhamnopyranoside(3),(-)-lyoniresinol-3α-O-β-D-glucopyranoside(4),(+)-lyoniresinol-3α-O-β-D-glucopyranoside(5),(-)-4-epi-lyoniresinol-9'-O-β-D-glucopyransoide(6), racemiside(7), neociwujiaphenol(8),(+)-syringaresinol(9), and homohesperitin(10). Among them, compound 1 was a new aryltetralin-type lignan. All the isolated lignans were tested for antioxidant activities in Fe~(2+)-cysteine induced rat liver microsomal lipid peroxidation in vitro, and compounds 8 and 9 showed antioxidant activities on the formation of malondiadehyde(MDA) in rat liver microsomes at 1×10~(-5) mol·L~(-1), with significant inhibitory rates of 75.20% and 91.12%, respectively.

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.

Cloning and functional analysis of the phenylalaninammo-nialyase gene from Rhododendron fortunei / 生物工程学报

Phenylalaninammo-nialyase (PAL) is a key enzyme in the synthesis of methyl benzoate - a plant aroma compound. In order to understand the function of this enzyme in the formation of fragrance in the scented Rhododendron species-Rhododendron fortunei, we cloned a gene encoding this enzyme and subsequently examined the gene expression patterns and the profile of enzyme activity during development in various tissues. The full length of RhPAL gene was cloned by reverse transcription-PCR (RT-PCR) and rapid amplification of cDNA ends (RACE) techniques. The expression levels of RhPAL gene were measured by real-time quantitative reverse transcription PCR (qRT-PCR) and the amount of phenylalanine and cinnamic acid were assayed with LC-MS. The results showed that the ORF sequence of RhPAL gene amplified from the cDNA templates of flower buds had 2 145 bp, encoding 715 amino acids, and shared 90% homology to the PAL amino acid sequences from other species. qRT-PCR analysis showed that the expression of RhPAL in petals during flowering kept in rising even until the flowers wilted. The expression of RhPAL in pistil was much higher than that in stamen, while the expression in the younger leaves was higher than in old leaves. However, the expression level was relatively lower in petal and stamen compared to that in leaves. We also measured the PAL activity by Enzyme-linked immuno sorbent assay in the petals of flowers at different flowering stages. The results showed that PAL activity reached the highest at the bud stage and then decreased gradually to the lowest when the flowers wilted, which followed a similar trend in the emission of the flower fragrance. The phenylalanine and cinnamic acid contents measured by LC-MS were highly correlated to the expression level of RhPAL in various tissues and at different flowering stages, implying that RhPAL plays an important role in the formation of the flower fragrance. This work may facilitate the breeding and improvement of new fragrant Rhododendron cultivars.

Anti-rheumatoid arthritis potential of diterpenoid fraction derived from Rhododendron molle fruits / 中国天然药物

Rhododendron molle G. Don is first recorded in Shengnong's Herbal Classic, and its fruits, which are termed as Liuzhouzi, are often used to treat rheumatoid arthritis in Chinese folk. During our ongoing investigation to develop a safer and potential new arthritis therapy, a process for the preparation of diterpenoid fraction from Rhododendron mollefruits was established. In order to evaluate the main components and the anti-rheumatoid arthritis effect of the diterpenoid fraction, phytochemical and pharmacological experiments were used. As the result, the main components of diterpenoid fraction were identified as rhodojaponin III (1), rhodojaponin VI (2), 2-O-methylrhodojaponin (3), and 5'-β-D-glucopyranosy-loxyjasmonic acid (4). These four components constitute greater than 95% of diterpenoid fraction using area normalization method of HPLC-ELSD. The results of CIA rat experiment showed that high dose of diterpenoid fraction (0.6 mg·kg

Content determination of five flavonoids in Tibetan medicine Rhododendron anthopogonoides by quantitative analysis of multi-components by single marker (QAMS) / 中国中药杂志

To establish a quantitative analysis of multi-components by single marker(QAMS) method for five flavonoids in Rhododendron anthopogonoides and verify its feasibility and applicability in the medicinal materials of R. anthopogonoides. With hyperoside as the internal reference, relative correction factors(RCF) of rutin, quercetin, quercitrin and kaempferol were established by high-performance liquid chromatography(HPLC) analysis. RCFs were used to calculate the content of each component, system durability and relative retention time. Simultaneously, QAMS and external standard method(ESM) were used to determine the content of five flavonoids in 12 batches of R. anthopogonoides from different origins. The results were statistically analyzed to verify the accuracy and feasibility. The fingerprints and cluster analysis data of R. anthopogonoides analyzed and discussed differences among the batches. According to the results, the RCFs of rutin, quercetin, quercetin and kaempferol in R. anthopogonoides were 1.242 6, 0.990 5, 0.535 0, and 0.781 3, respectively. The RCFs represented a good reproducibility under different experimental conditions. Besides, there was no significant difference between QAMS and ESM. Besides, the fingerprint and cluster analysis data showed the consistency between the classification and with the origin distribution of the herbs. In conclusion, the QAMS method shows a good stability and accuracy in the quality control of R. anthopogonoides.

Herbal Textual Research and Processing Historical Evolution of Rhododendri Mollis Flos / 中国实验方剂学杂志

In this paper， through the collection and collation of ancient materia medica， medical books and medical formulary， combining with modern literature， the historical changes of the name， origin， position， harvesting time， medicinal parts， toxicity， functions and indications， processing methods of Rhododendri Mollis Flos （RMF） were systematically combed and verified， so as to provide reference for clinical application， processing standard and basic research of RMF. According to textual research， RMF is the dried flower of Rhododendron molle. In each historical period， there are many aliases and local names， being with phenomenon of homonyms and synonyms. RMF is mostly wild and planted in a small amount， harvesting time is mostly in March to April. However， the harvesting flowering period is differently described as initial bloom， full bloom and extensive bloom. RMF was first recorded in Shennong Bencaojing (《神农本草经》)， but it did not mention its medicinal parts. Then the flowers， fruits， roots are be used as medicine， but flowers are still the main medicinal parts. RMF had a long processing history， included fried， vinegar-fried， wine-fried， steamed， wine-steamed， vinegar-steamed， and many other processing methods in ancient times. However， at present， only raw products are used in clinical practice， and only a few modern books retain the methods of stir-fried and wine-steamed， believing that the processing can reduce toxicity of RMF.

Antinociceptive grayanane-derived diterpenoids from flowers of

Twelve new grayanoids (-) along with five known compounds were isolated from flowers of . Their structures were fully characterized using a combination of spectroscopic analyses, computational calculations, and single crystal X-ray diffraction. Rhomollone A () possesses an unprecedented 5/6/6/5 tetra-cyclic ring system (B- grayanane) incorporating a cyclopentene-1,3-dione scaffold. Rhodomollein XLIII () is a dimeric grayanoid, containing a novel 14-membered heterocyclic ring with a symmetry axis. The antinociceptive activities of compounds , , , , and - were evaluated by an acetic acid-induced writhing test. Among them, compounds , , , and displayed significant antinociceptive activities at a dose of 20 mg/kg with inhibition rates ranging from 41.9% to 91.6%. Compounds and inhibited 46.0% and 39.4% of the acetic acid-induced writhes at a dose of 2 mg/kg, while compound inhibited 34.3% of the writhes at a dose of 0.4 mg/kg.

Research progress on chemical constituents of Rhododendron molle and its pharmacological activities / 中草药

Rhododendron molle is a plant of the Ericaceae family. It is commonly used in the treatment of rheumatoid arthritis. Modern pharmacological studies have confirmed that its diterpenoids are main medicinal ingredients with anti-inflammatory, analgesic and other pharmacological effects. Through reviewing domestic and foreign literatures, this review aims to provide a comprehensive overview of the research progress in the chemical constituents and pharmacological effects of R. molle, and briefly prospects research of the titled plant.

Protective effect of Rhododendron weyrichii flower extract against UVB-induced proinflammatory cytokine production in human keratinocytes

Ultraviolet B (UVB) radiation is harmful to the skin and induces cytokine release from keratinocytes leading toinflammatory skin disorders. Previous studies have shown that chronic exposure to UVB radiation increases tumornecrosis factor (TNF)-α and interleukin (IL)-6 secretion through various signaling pathways, resulting in skininflammation and increased risk of skin cancer. The present study was undertaken to investigate the protective effectsof Rhododendron weyrichii flower (RWF) extracts against UVB damage of immortalized human keratinocytes(HaCaT). To determine the anti-inflammatory effects of RWF, we examined UVB-induced proinflammatory cytokineproduction in HaCaT cells in the presence or absence of RWF extract, using enzyme-linked immunosorbent assay(ELISA). The results indicated that the RWF extract inhibited the production of proinflammatory molecules suchas IL-6 and TNF-α, but not IL-8, in UVB-irradiated HaCaT cells. These results demonstrate that RWF potentiallyprotects against UVB-induced skin inflammation. In addition, using high-performance liquid chromatography (HPLC)fingerprinting, kaempferol (0.335 ppm) and astragalin (2.569 ppm) were identified and quantified as RWF extractconstituents. Moreover, we tested the potential application of RWF extracts as a cosmetic treatment by performinghuman skin primary irritation tests. In these tests, the RWF extracts did not induce adverse reactions. Based on theseresults, we suggest that RWF extracts be considered anti-inflammatory candidates for pharmaceutical and/or cosmeticapplications.

Enantiomeric pairs of meroterpenoids from Rhododendron fastigiatum / 中国天然药物

Five pairs of optically pure meroterpenoid enantiomers (1a/1b-5a/5b) and two known compounds (6 and 7) were isolated from Rhododendron fastigiatum. Compounds 1a/1b-5a/5b were resolved from naturally scalemic mixtures by chiral HPLC. Their structures were elucidated by spectroscopic methods, X-ray crystallographic experiments, and ECD analyses. Compounds 1a/1b, 2a/2b, 3b, 4a/4b, and 5a/5b were new meroterpenoids with different polycyclic systems. Two enantiomeric pairs (2a/2b and 3a/3b), 6, and 7 exhibited inhibitory effects on protein tyrosine phosphatase 1B (PTP1B) in vitro.

Study of manufacturing technology of tablet formulation from Rhododendron Adamsii Rehd / Монголын эм зүй, эм судлал

Abstract@#We have worked on the research related with total flavonoid isolated Rhododendron Adamsii Rehder, which enhance and restore physical energy and reduce mental pain. According to the result, the highest amount (2.4±0.007%) of the total flavonoids was found in the 40% ethanol extract of Rhododendron Adamsii Rehder at 60 minutes of extraction time. Subsequently, the granulated formulation from the extract of Rhododendron Adamsii Rehder was prepared by using 4% of gelatin, 4% of polyvinylchloride and 4% of carboxymethyl cellulose. The fluidity and pouring weight of the granule was evaluated and 4% of gelatin was chosen as the suitable binder for the formulation. In conclusion, we have successfully developed the granulated formulation from Rhododendron Adamsii Rehder.

Rhododendron Molle (Ericaceae): phytochemistry, pharmacology, and toxicology / 中国天然药物

Rhododendron molle G. Don, belonging to the Ericaceae family, is a traditional Chinese medicinal plant with a wide spectrum of pharmacological effects. This paper aimed to review the phytochemistry, pharmacology and toxicology of R. molle, and to discuss the tendency of future investigations on this plant. A systematic review of literature about R. molle was carried out using resources including classic books about Chinese herbal medicine, and scientific data bases including CNKI, Pubmed, SciFinder, Scopus, and Web of Science. Over 67 compounds, including diterpenes, triterpenes, flavonoids, and lignans, had been extracted and identified from R. molle. The extracts/monomers isolated from the root, flower and fruits of this plant were used as effective agents for treating pains, inflammatory diseases, hypertension, and pest, etc. In addition, diterpenes, such as rhodojaponin III, were considered as the toxic agents associated with the toxicities of this plant. These findings will be significant for the discovery of new drugs from this plant and full utilization of R. molle.

Rhododendron Molle (Ericaceae): phytochemistry, pharmacology, and toxicology / 中国天然药物

Rhododendron molle G. Don, belonging to the Ericaceae family, is a traditional Chinese medicinal plant with a wide spectrum of pharmacological effects. This paper aimed to review the phytochemistry, pharmacology and toxicology of R. molle, and to discuss the tendency of future investigations on this plant. A systematic review of literature about R. molle was carried out using resources including classic books about Chinese herbal medicine, and scientific data bases including CNKI, Pubmed, SciFinder, Scopus, and Web of Science. Over 67 compounds, including diterpenes, triterpenes, flavonoids, and lignans, had been extracted and identified from R. molle. The extracts/monomers isolated from the root, flower and fruits of this plant were used as effective agents for treating pains, inflammatory diseases, hypertension, and pest, etc. In addition, diterpenes, such as rhodojaponin III, were considered as the toxic agents associated with the toxicities of this plant. These findings will be significant for the discovery of new drugs from this plant and full utilization of R. molle.

Chemical constituents from fruits of Rhododendron molle / 中草药

Objective: To investigate the chemical constituents from the fruits of Rhododendron molle. Methods: Compounds were isolated and purified by a series of methods including silica gel, ODS column, Sephadex LH-20, semi-preparative HPLC, recrystallization, and so on. Their structures were identified by analysis of physico-chemical propertiesand spectroscopic technique. Results: Fifteen known compounds were isolated and their structures were elucidated as myricetin (1), dihydromyricetin (2), gallocatechin (3), quercetin-3′-O-glycoside (4), catechin (5), epicatechin (6), taxifolin 3′-O-glucopyranoside (7), proanthocyanidin A-2 (8), dehydroicatechin A (9), quercetin-3-O-α-arabinoside (10), phlorizin (11), lyoniresinol 3-O-rhamnopyranoside (12), 2,6- dimethoxy-4-hydroxyphenol-1-O-glucopyranoside (13), 2,4,6-trihydroxy acetophenone-2-O-glucopyranoside (14), and 5′-β- glucopyranosyloxy-jasmonic acid (15). Conclusion: Compounds 1—4, 7—9, and 13—15 are obtained from R. molle for the first time. Compounds 5, 6, and 10—12 are obtained from the fruits of this plant for the first time, of which compounds 1—11 are flavonoids.

SPECTROPHOTOMETRIC ANALYSIS OF THE ETHANOL EXTRACTS FROM THE RHODODENDRON ADAMSII REHD / Монголын эм зүй, эм судлал

Introduction: In recent years, due to the increase in population density, noisiness and air pollution, people’s life rhythm has been changing dramatically and it is creating stress both mentally and physically for human beings. Therefore, this research is to extract a pill from an adaptogenic domestic herb Rhododendron Adamsi Rehd using its parts on the earth surface. Materials and methods: Analysis of determination biologically active substances in the ethanol extracts from the Rhododendron Adamsii Rehd. The main material for the research is the aerial parts of Rhododendron Adamsi Rehd which grows on the earth surface during the blooming period of the herb in the area of Ulaan-Uul soum in Khuvsgul province. Also following materials were used in the research: Spectrophotometer (UV/VIS 1700), electric measurement, soxhlet extractor, ethanol, aluminum chloride, Sodium nitrite, sodium hydroxide solution. Rhododendron Adamsii Rehd extracting in 40% and 70% ethyl alcohol 60, 120 and 180 minutes (reflux) are extracted and spectrometric survey found the total flavonoid content, the most sensitive to wavelengths that extra cts from each method. Results: Rhododendron Adamsii Rehd are proven to be 60 minutes for 40% of ethanol extraction is suitable for the determination of total flavonoids. We are researching of this extract most sensitive wavelength between 190-500 nm. This research result shown that total flavonoid 0,648-0,67 light absorption at a wavelength of 255-257 nm; 258-259 nm wavelength light absorption 0,673; 260-262 nm were 0,66-0,67 light absorption. The fact proven to be most sensitive wavelength of 40% ethanol extract is 258-259 nm. Rhododendron Adamsii Rehd were suitable for extraction of 70% ethanol during 60-120 minutes. Total flavonoid of this extract absorption 1,478-1,757 at a wavelength 250-254 nm 255-256 nm wavelength light absorption 1,764-1,788; 1,731 at a wavelength 260 nm light absorption. This shows that proven to be most sensitive to wavelength of 70% ethanol extract is 255- 256 nm. Rhododendron Adamsii Rehd water extraction agent 30 ± 0.01% (p <0.001) and total flavonoids 40% of ethanol extract content: 1.77-2,6 ± 0.03% (p <0.0001); 70% of ethanol extract content: 2,4-7.46 ± 0.01% (p <0.0001). Сonclusion: The study results were total carotenoid 0.278 ± 0.03% of 40% ethanol extract (p <0.005) and total carotenoid 1,263± 0.05% (p <0.001) of 70% ethanol extract. Key words: Rhododendron Adamsii Rehd, total flavonoid, total carotenoid

The effect of rhododendron honey on mice liver tissue / Efecto de la miel de rododendro en el tejido hepático de ratón

Rhododendron honey, made by bees from rhododendron pollen, contains a toxic substance called grayanotoxin. Depending on the dose, the poisonous honey can result in serious effects such as cardiac arrhythmia, fibrillation, and myocardial infarction. The purpose of this study is to investigate the effects of the poisonous RH of the Black Sea Region on the liver. Male mice were divided into five groups of twelve mice each, two being the control groups (distilled water) and the others being the rhododendron honey (RH) groups (25, 50, and 75 mg/kg) and 0.01 mg/kg grayanotoxin (GTx) groups. Liver tissues were collected 24 and 48 h later. The sections were stained with hematoxylin, eosin and PAS, then the histopathological score was performed. Significant statistical differences were observed between the RH and control groups in terms of congestion, steatosis, sinusoid dilatation, and inflammation. The control group demonstrated a normal liver structure in the light microscopy, while the GTx-applied 24 h group exhibited expansions in the sinusoids and congestion. Higher levels of congestion, steatosis, and inflammatory cells were seen in the GTx-applied 48 h group. In the same group, giant cells consisting of many nuclei were observed in the sinusoids. The results of the 25 mg RH-applied groups were similar in 24 and 48 h, histopathological score levels were increased slightly, congestion and steatosis were prominent in the 48 h group. Dense steatosis was seen in the hepatocytes around the vena centralis in 50 mg/kg RH-applied 48 h group. Congestion, steatosis and an increase in inflammatory cells were observed in the hepatocytes in the 75 mg/kg RH-applied 24- and 48 h groups. PAS (+) stained hepatocytes were decreased in the RH- and GTx-applied groups. The toxic effects of the rhododendron honey were observed in the mice liver tissue with respect to dose and time.

La miel de rododendro, elaborada por las abejas a partir del polen de rododendro, contiene una sustancia tóxica llamada grayanotoxina. Dependiendo de la dosis, la miel venenosa puede resultar en efectos graves, tales como arritmia cardiaca, fibrilación e infarto de miocardio. El propósito de este estudio fue investigar los efectos en el hígado de la miel venenosa de rododendro de la región del Mar Negro. Se distribuyeron ratones machos en cinco grupos de doce ratones cada uno, dos grupos control (agua destilada) y los otros grupos se trataron con la miel de rododendro (MR) (25, 50 y 75 mg/kg) y con 0,01 mg/kg grayanotoxina (GTX). Los tejidos hepáticos se recogieron 24 y 48 h más tarde. Las secciones fueron teñidas con hematoxilina-eosina y PAS. A continuación, se realizó la puntuación histopatológica. No se observaron diferencias estadísticamente significativas entre MR y los grupos de control en términos de congestión, esteatosis, dilatación sinusoidal e inflamación. El grupo control demostró una estructura normal del hígado en el microscopio de luz, mientras que el grupo de las 24 horas de aplicación de GTX exhibió expansiones en los sinusoides y congestión. Mayores niveles de congestión, esteatosis y células inflamatorias se observaron en el grupo de 48-horas de aplicación de GTX. En el mismo grupo, se observaron células gigantes que consistían en la presencia de muchos núcleos en los sinusoides. Los resultados de los grupos con aplicación de 25 mg de RH fueron similares en los resultados de 24 y 48 h, los niveles de puntuación histopatológica aumentaron ligeramente, la congestión y la esteatosis fueron prominentes en el grupo de 48 h. Se observó esteatosis densa en los hepatocitos en toda la vena central en el grupo de aplicación de 50 mg/kg de RH, 48 h. La congestión, la esteatosis y un aumento en las células inflamatorias se observaron en los hepatocitos en el grupo de 75 mg/kg de MR de 24 h y los grupos de 48 h. Hepatocitos teñidos con PAS (+) disminuyeron en los grupos de GTX y MR. Se observaron los efectos tóxicos de la miel de rododendro en el tejido hepático de ratones con respecto a la dosis y el tiempo.

Chemical constituents from Rhododendron anthopogonoides / 中草药

Objective: To study the chemical compositions of Rhododendron anthopogonoides. Methods: The chemical constituents were isolated from R. anthopogonoides by Sephadex LH-20, MCI, silica gel column chromatography, and preparative-HPLC. The structures were assigned by physicochemical property and spectroscopic data. Results: Ten compounds have been isolated from R. anthopogonoides and their structures were indentified as caffeic acid (1), trans-ferulic acid (2), kaempferol (3), dihydroquercetin (4), noreugenin (5), 4-(3,4-dihydroxyphenyl)-2-butanone (6), 3,5-dihydroxy toluene (7), ursolic acid (8), ethyl 3,4-dihydroxybenzoate (9), and procurcumenol (10). Conclusion: Compounds 1-3, 5-7, 9, and 10 are obtained from R. anthopogonoides for the first time. Compounds 2,6,9, and 10 are obtained from the plants of Rhododendron L. for the first time.

Identification and characterization of three new flavonoids from Rhododendron dauricum / 中国天然药物

The present study was designed to determine the major chemical constituents of the leaves of Rhododendron dauricum L. Compounds were isolated and purified by various chromatographic methods, and their structures were elucidated by physicochemical properties and spectral data. The present study identified two new C-methyl flavanones, 5, 7, 3', 5'-tetrahydroxy-6, 8-di-C-methyl flavanone (1) and 5, 4'-dihydroxy-8-C-methylflavanone-7-O-β-D-glucopyranoside (2), and one new flavonoid glycoside, quercetin-3-O-β-D-(6"-O-cinnamoyl)-galactoside (3), along with seven known compounds, including syzalterin (4), poriolin (5), farrerol-7-O-β-D-glucopyranoside (6), myrciacetin (7), quercetin-3-O-β-D-(6-p-hydroxy-benzoyl)-galactoside (8), quercetin-3-O-β-D-(6-p-coumaroyl)-galactoside (9), and 5, 7, 3', 5'-tetrahydroxyl flavanone (10). Compounds 1-3 were determined to be new flavonoids; compounds 4-6 were isolated from this species for the first time; and compounds 7-10 were reported for the first time from this genus.