Rheum
Emodin
Butanones
Study on anti-Oketsu activity of rhubarb II. Anti-allergic effects of stilbene components from Rhei undulati Rhizoma (dried rhizome of Rheum undulatum cultivated in Korea). (1/60)
Methanol extract (RM-ext) obtained from the dried rhizome of Rheum undulatum was screened for activity in experimental models of type I allergy. RM-ext exhibited the inhibition on 48-h homologous passive cutaneous anaphylaxis (PCA) in rats and an antigen-induced histamine release from rat peritoneal mast cells. Among nine stilbenes isolated from RM-ext, seven inhibited the histamine release. Rhapontigenin (compound 1), piceatannol (2) and piceatannol 3'-beta-D-glycoside (6) with oral administration showed the inhibition on PCA. Compounds 1 and 2 exhibited the inhibitory effect on sheep red blood cell-induced delayed-type hyper sensitivity (SRBC-DTH) of type IV allergic model. These results indicated that the rhizome of Rheum undulatum inhibits the allergic reactions and that these inhibitory effects may be partially attributable to the stilbenes mentioned above. (+info)Cloning and characterization of the gene cluster for palatinose metabolism from the phytopathogenic bacterium Erwinia rhapontici. (2/60)
Erwinia rhapontici is able to convert sucrose into isomaltulose (palatinose, 6-O-alpha-D-glucopyranosyl-D-fructose) and trehalulose (1-O-alpha-D-glucopyranosyl-D-fructose) by the activity of a sucrose isomerase. These sucrose isomers cannot be metabolized by plant cells and most other organisms and therefore are possibly advantageous for the pathogen. This view is supported by the observation that in vitro yeast invertase activity can be inhibited by palatinose, thus preventing sucrose consumption. Due to the lack of genetic information, the role of sucrose isomers in pathogenicity has not been evaluated. Here we describe for the first time the cloning and characterization of the palatinose (pal) genes from Erwinia rhapontici. To this end, a 15-kb chromosomal DNA fragment containing nine complete open reading frames (ORFs) was cloned. The pal gene products of Erwinia rhapontici were shown to be homologous to proteins involved in uptake and metabolism of various sugars from other microorganisms. The palE, palF, palG, palH, palK, palQ, and palZ genes were oriented divergently with respect to the palR and palI genes, and sequence analysis suggested that the first set of genes constitutes an operon. Northern blot analysis of RNA extracted from bacteria grown under various conditions implies that the expression of the palI gene and the palEFGHKQZ genes is oppositely regulated at the transcriptional level. Genes involved in palatinose uptake and metabolism are down regulated by sucrose and activated by palatinose. Palatinose activation is inhibited by sucrose. Functional expression of palI and palQ in Escherichia coli revealed sucrose isomerase and palatinase activity, respectively. (+info)Effect of mirabilitum in formularization: change of prolyl endopeptidase inhibitory activity and of constituents using the preparation method of Tokaku-joki-to. (3/60)
To clarify the effect of Mirabilitum in formularization, change of prolyl endopeptidase inhibitory activity and of constituents using the preparation method of a Kampo formula Tokaku-joki-to ([Japanese characters: see text], Persia and Rhubarb combination) was examined by the liquid chromatography-mass spectroscopy (LC-MS) method. Mirabilitum under boiling condition caused qualitative and quantitative change of the constituents through hydrolysis which caused a change of its activity. This was considered to be the main reason the classical Chinese medical book "Shang han lun ([Japanese characters: see text])" specified that Mirabilitum should be added at a later stage of decoction. (+info)Benzalacetone synthase. A novel polyketide synthase that plays a crucial role in the biosynthesis of phenylbutanones in Rheum palmatum. (4/60)
Benzalacetone synthase (BSA) is a novel plant-specific polyketide synthase that catalyzes a one step decarboxylative condensation of 4-coumaroyl-CoA with malonyl-CoA to produce the C6-C4 skeleton of phenylbutanoids in higher plants. A cDNA encoding BAS was for the first time cloned and sequenced from rhubarb (Rheum palmatum), a medicinal plant rich in phenylbutanoids including pharmaceutically important phenylbutanone glucoside, lindleyin. The cDNA encoded a 42-kDa protein that shares 60-75% amino-acid sequence identity with other members of the CHS-superfamily enzymes. Interestingly, R. palmatum BAS lacks the active-site Phe215 residue (numbering in CHS) which has been proposed to help orient substrates and intermediates during the sequential condensation of 4-coumaroyl-CoA with malonyl-CoA in CHS. On the other hand, the catalytic cysteine-histidine dyad (Cys164-His303) in CHS is well conserved in BAS. A recombinant enzyme expressed in Escherichia coli efficiently afforded benzalacetone as a single product from 4-coumaroyl-CoA and malonyl-CoA. Further, in contrast with CHS that showed broad substrate specificity toward aliphatic CoA esters, BAS did not accept hexanoyl-CoA, isobutyryl-CoA, isovaleryl-CoA, and acetyl-CoA as a substrate. Finally, besides the phenylbutanones in rhubarb, BAS has been proposed to play a crucial role for the construction of the C6-C4 moiety of a variety of natural products such as medicinally important gingerols in ginger plant. (+info)Rhubarb use in patients treated with Kampo medicines--a risk for gastric cancer? (5/60)
In vitro mutagenic effects have been reported for ingredients contained in rhubarb. Therefore, rhubarb (Rhei Rhizoma) as an anthranoid laxative could be associated with a risk of developing gastric cancer as well as colorectal cancer. We are not aware of any reports that have examined the relationship between the use of rhubarb and the development of gastric cancer. During the period between 1979 and 1999, we treated 14,616 patients using various Kampo medicines, which sometimes contained rhubarb. In the present study, we determined whether patients, diagnosed with gastric cancer during the period between 1979 and 1999, had been administered rhubarb before the development of gastric cancer. Among the 10 enrolled patients, only 2 patients had been administered rhubarb before the development of gastric carcinoma. The other 8 patients had never received rhubarb before the development of gastric carcinoma. Rhubarb use may have little connection with the development of gastric cancer in practice, even if some ingredients in rhubarb have shown carcinogenic activity in experimental studies. (+info)Oxalic acid is available as a natural antioxidant in some systems. (6/60)
Oxalic acid is found in a wide variety of plants. This study showed that oxalic acid suppressed in vitro lipid peroxidation in a concentration-dependent manner. Furthermore, oxalic acid reduced the rate of ascorbic acid oxidation in the presence of hydrogen peroxide and Cu(2+). These results suggest that oxalic acid is available as a natural antioxidant. (+info)The phytochemical lindleyin, isolated from Rhei rhizoma, mediates hormonal effects through estrogen receptors. (7/60)
Some plant compounds or herb mixtures are popular alternatives to conventional therapies and contain organic compounds that bind to some nuclear receptors, such as the estrogen receptor (ER), to exert various biological effects. We studied the effect of various herbal extracts on ERalpha and ERbeta isoforms. One herbal extract, Rhei rhizoma (rhubarb), acts as an agonist to both ERalpha and ERbeta. The phytochemical lindleyin, a major component of rhubarb, might contribute to this estrogenic activity through ERalpha and ERbeta. 4-Hydroxytamoxifen, an ER antagonist, completely reversed the estrogenic activity of lindleyin. Lindleyin binds to ERalpha in vitro, as demonstrated using a fluorescent polarization assay. The in vivo effect of rhubarb extract was studied using a vitellogenin assay system in the freshwater fish, Japanese medaka (Oryzias latipes). There were marked increases in serum vitellogenin levels in male medaka exposed to rhubarb extract. We conclude that lindleyin, a component of some herbal medicines, is a novel phytoestrogen and might trigger many of the biological responses evoked by the physiological estrogens. (+info)Effects of Rheum tanguticum polysaccharide on TNBS -induced colitis and CD4+T cells in rats. (8/60)
AIM: To study the effects of Rheum tanguticum polysaccharide(-1) (RTP(-1)) on ulcerative colitis in rats induced by 2, 4, 6-trinitrophene sulphonic acid (TNBS) and their possible mechanism. METHODS: RTP1 (200 mg.kg(-1), i.g.) extracted from Rheum tanguticum Maxim. ex Regel was administrated to rats with colitis induced by TNBS for 5 d, 7 d, 10 d and 14 d, respectively. The effects of RTP1 and dexamethasone (DX, 0.2 mg.kg(-1), i.g.) were contrastively investigated. The MPO level and SOD activity were determined by chromatometry. The expansion and protein expression of CD4+T lymphocytes isolated from colon mucosae and mesenteric lymph nodes of colitis rats were performed by immunohistochemical analysis and Western-blot methods. RESULTS: Treatments of RTP1 (200 mg.kg(-1), i.g.) significantly reduced diarrhea, mortality, colon mass, ulcer areas and MPO level in colon mucosae on days 5, 7, 10 and 14 (5.2+/-1.4, 5.4+/-0.7, 5.2+/-1.8, P<0.05. 3.4+/-0.8, P<0.01. 16.1+/-12.1, P<0.01. 31.8+/-8.6, 17.7+/-5.3, 12.7+/-4.1, P<0.05). The effects of RTP1 were similar to those noted above in DX group, but there were no immunosuppressive effects of DX in RTP(-1) group, such as body mass loss, thymus and spleen atrophy. The decreased number and down-regulated protein levels of CD4+T cells isolated from the colon of colitis rats treated with RTP1 were found. CONCLUSION: RTP1 shows significantly protective effects but lower side effects on rats with colitis induced by TNBS. The mechanism may be due to the resistance to over expansion of CD4. (+info)In medical terms, "Rheum" is not a specific disease or condition. Instead, it is a term that was historically used to refer to a variety of disorders characterized by inflammation and pain in the musculoskeletal system, particularly in the joints. These disorders were often associated with symptoms such as stiffness, swelling, and warmth in the affected areas.
Over time, the term "rheumatic diseases" has become more commonly used to describe this group of conditions. Rheumatic diseases now encompass a wide range of disorders that affect the joints, muscles, tendons, ligaments, bones, and other connective tissues. Examples include rheumatoid arthritis, osteoarthritis, lupus, gout, and many others.
It's important to note that while "rheum" is an outdated term in modern medical nomenclature, it still holds historical significance and is sometimes used in the names of certain medical conditions or concepts, such as "rheumatology," which is the medical specialty focused on the diagnosis and management of rheumatic diseases.
Emodin is a natural anthraquinone compound that can be found in various plants such as rhubarb, knotweed, and Japanese knotweed. It has been reported to have various biological activities, including anti-inflammatory, antiviral, and anticancer effects. However, more research is needed to confirm these potential health benefits and to understand the mechanisms of action.
Emodin can also interact with certain drugs and may cause adverse effects, so it's important to consult a healthcare professional before taking any supplements containing emodin.
"Sapindus" is a botanical term that refers to a genus of trees in the soapberry family (Sapindaceae). These trees are native to warm temperate to tropical regions of the world. The fruit of these trees contains saponins, which have cleansing properties and have been used as a natural soap for washing.
However, "Sapindus" is not a medical term and does not have a specific medical definition. If you are looking for information about the medicinal uses or health benefits of Sapindus trees or their fruit, I would recommend consulting reliable sources of information on herbal medicine or speaking with a healthcare provider who has expertise in this area.
Butanones are a group of chemical compounds that contain a ketone functional group and have the molecular formula C4H8O. They are also known as methyl ethyl ketones or MEKs. The simplest butanone is called methyl ethyl ketone (MEK) or 2-butanone, which has a chain of four carbon atoms with a ketone group in the second position. Other butanones include diethyl ketone (3-pentanone), which has a ketone group in the third position, and methyl isobutyl ketone (MIBK) or 4-methyl-2-pentanone, which has a branched chain with a ketone group in the second position.
Butanones are commonly used as solvents in various industrial applications, such as paint thinners, adhesives, and cleaning agents. They have a characteristic odor and can be harmful if ingested or inhaled in large quantities. Exposure to butanones can cause irritation of the eyes, skin, and respiratory tract, and prolonged exposure may lead to neurological symptoms such as dizziness, headache, and nausea.