Anthraquinone-containing compound in rhubarb prevents indole production via functional changes in gut microbiota.

Indole is produced from dietary tryptophan by tryptophanase in intestinal bacteria, such as Escherichia coli. In the liver, indole is converted into indoxyl sulfate, a uremic toxin and risk factor for chronic kidney disease (CKD). Probiotics and prebiotics are currently used for suppressing CKD, but there are no drugs that directly suppress indole production. In this study, we developed an optimized HPLC method for analyzing indole production and evaluated the effect of diets and rhubarb on indole production via the changes of gut microbiota. In high-carbohydrate and high-fat diet-fed mice, the indole production was significantly higher than in high-fiber diet-fed mice. We further used the high-carbohydrate diet-fed mice as a model for examining the effect of rhubarb on indole production. The 20% methanol-eluted fraction of aqueous rhubarb extract significantly suppressed indole production, and the eluate constituent rhein 8-O-ß-D-glucopyranoside (RG) contributed to this effect in a concentration-dependent manner. The effect of RG depended on the anthraquinone core substructure, i.e., the aglycone moiety (rhein) of RG, which appeared to inhibit the tryptophanase function in gut microbiota. Thus, in addition to earlier reports that rhubarb is an effective CKD treatment, our study demonstrated that the anthraquinone moiety in rhubarb prevents uremic toxin production via functional changes in gut microbiota, which suppresses CKD progression.

Determination of Short-Chain Fatty Acids in Mouse Feces by High-Performance Liquid Chromatography Using 2-Nitrophenylhydrazine as a Labeling Reagent.

It has been suggested that imbalances in gut microbiota are related to diseases associated with metabolism, the central nervous system, etc. Therefore, analysis of short-chain fatty acids (SCFAs) produced by gut microbiota is very important as an indicator of causation, demonstrating the effects on the host due to changes in the gut microbiota. We developed a HPLC method for the determination of SCFAs in mouse feces. After homogenization, the SCFAs in mouse feces and 2-ethylbutyric acid (internal standard) were derivatized with 2-nitrophenylhydrazine (2-NPH) in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide. The 2-NPH derivatives of SCFAs and the internal standard were separated on a reversed-phase column (octadecyl silyl column) by gradient elution using phosphoric acid (pH 2.5)-acetonitrile at 50°C and detected by absorbance measurement at 400 nm. The recovery of the method was 90-115%, with a precision (relative standard deviation) of 1.3-7.7%. The determination of SCFAs by the present method can provide useful information for biological and clinical research.

Daiokanzoto (Da-Huang-Gan-Cao-Tang) is an effective laxative in gut microbiota associated with constipation.

Interindividual differences affect the purgative activities of sennoside A (SA) and Daiokanzoto (Da-Huang-Gan-Cao-Tang, DKT). In this study, we manipulated gut microbiota in mice to establish laxative responders and non-responders by feeding them a high-carbohydrate, a high-fat or a high-fibre diet. To assess the relationship between laxatives and gut microbiota, we monitored the gut microbiota before and after administering laxatives. Twenty mice per diet were divided into four groups of five mice to evaluate purgative activities of four laxative preparations, DKT, SA, SA plus rhein 8-O-ß-D-glucopyranoside (SA + RG), and SA plus liquiritin (SA + LQ). Gut microbiota changes were monitored by next-generation sequencing of 16 S rRNA gene amplicons. In high-carbohydrate and high-fat diet-fed mice, DKT exerted a significantly higher purgative activity than SA alone, and RG contributed to this activity. DKT and SA + RG administration increased the Enterobacteriaceae content of gut microbiota, which was associated with an increased purgative activity. In contrast, DKT activity was significantly suppressed by high-fibre diet. Hence, diet-induced differences in gut microbiota determined the effect of DKT, which is interesting, considering that Oriental medicines are formulated for a specific functional state or "pattern". These results demonstrated that the purgative activity of anthranoid laxatives is susceptible to diet-induced alterations in gut microbiota.

Rhein 8-O-ß-D-Glucopyranoside Elicited the Purgative Action of Daiokanzoto (Da-Huang-Gan-Cao-Tang), Despite Dysbiosis by Ampicillin.

Sennoside A (SA), the main purgative constituent of Daiokanzoto (da-huang-gan-cao-tang; DKT), is generally regarded as a prodrug that is transformed into an active metabolite by ß-glucosidase derived from Bifidobacterium spp. It has been suggested that antibiotics would promote dysbiosis, and thereby inhibit the purgative activity of DKT. In this study, ampicillin was administered to mice for 8 d, and the changes in the SA metabolism of SA alone and of DKT were investigated. The results showed that the SA metabolism of SA singly continued to be inhibited by ampicillin, but that of DKT was activated from day 3 under the same conditions. In order to investigate the mechanism of SA metabolism activated by DKT in the mice administered ampicillin, changes in the SA metabolism were observed in the presence of rhein 8-O-ß-D-glucopyranoside (RG) in rhubarb and liquiritin in glycyrrhiza, both of which accelerated the SA metabolism. In fact, RG achieved an activation of SA metabolism similar to that by DKT. The purgative action of DKT, which was continued treatment of the ampicillin, was significantly greater than that by SA alone, and it was shown that RG was involved in this effect. We also analyzed changes in the intestinal microbiota before and after administration of ampicillin. No Bifidobacteria were detected throughout the treatment, but the population of Bacteroides was significantly increased after 3 d under the same conditions. Taken together, these results strongly suggested that the RG in DKT changed the function of Bacteroides and thereby allowed DKT to metabolize SA.

Examination of patients suspected as having hypersensitivity to iodinated contrast media with leukocyte migration test.

In vivo tests may be used for the diagnosis of allergy to iodinated contrast media (ICM); however, the tests do not provide definitive diagnosis and are associated with risks for patients. Diagnoses based on in vitro tests are limited, and there are almost no relevant studies. Herein, the authors examined involvement of allergic reaction from a multilateral standpoint in 39 patients suspected of having ICM allergies using leukocyte migration test (LMT). The positive rate of LMT was 44%. A comparison with the positive rate of LMT in drugs other than ICM (74%) indicated 30% difference, which was significantly low value, suggesting that there is poor involvement of these drugs in the allergic reaction. In LMT positives, 76% of hypersensitivity reactions were skin rash mainly erythema, and 18% was anaphylactic reactions. Cases considered as non-immediate hypersensitivity accounted for about 4 times as many as immediate-type hypersensitivity. In examination of relevancy between a history of drugs or food allergies, the incidence of ICM allergies was 35%. There is a high possibility that these adverse reactions were caused by pseudoallergy to drug. It was suggested that most hypersensitivity reactions were skin rash related to non-immediate hypersensitivity, and approximately 20% of the reaction was immediate anaphylactic reaction. Therefore attention should be paid not only to immediate-type hypersensitivity but also delayed reactions. Moreover, it was considered that patients with past history of drug or food allergies have a high potential for manifestation of the reactions.

Study on patients who underwent suspected diagnosis of allergy to amide-type local anesthetic agents by the leukocyte migration test.

BACKGROUND: There are problems in diagnosis of allergy to amide-type local anesthetic agents (ALAs), because definitive diagnosis is not obtained by in vivo tests, which are used for the diagnosis. Consequently, patients may be exposed to risk. There are few diagnoses based on in vitro tests, and there are almost no relevant studies. METHODS: Authors examined involvement of allergic reaction using the leukocyte migration test (LMT) through multiple standpoints in 43 patients who underwent suspected diagnosis of allergy to ALAs. RESULTS: Rate of LMT-positives was 54%, and especially the positive rate of lidocaine hydrochloride preparations was significantly high. In 15 positives to lidocaine hydrochloride preparations, all cases were indicated as positive in a test with drugs containing antiseptic agent, but only 3 cases were indicated as positive in a test with lidocaine hydrochloride alone. In addition, test with paraben was conducted in 4 cases; 2 cases were confirmed as positive. In relevance of histories of drug or food allergies, development rates of ALAs-allergies were the highest in both allergies, and were 35% and 13%, respectively. CONCLUSIONS: There is a high possibility that these adverse reactions were caused by pseudoallergy to drug. Even by allergic reactions, it was assumed that 80% of them might be caused by antiseptic agents such as paraben. In addition, it was suggested that ALAs, especially lidocaine hydrochloride preparations have high antigenicity (sensitizing property). Furthermore, it was considered that patients with past history of drug or food allergies have a high potential for manifestation of the reactions.

[Identification of the immunogenic outer membrane proteins of relapsing fever Borrelia].

Borrelia duttonii, a causative agent of relapsing fever, is transmitted between the distinct microenvironments of the vector tick, Ornithodoros moubata, and a mammalian host. We identified the total and membrane fraction proteins of B. duttonii strain Ly isolated from a patient in Tanzania by using two-dimensional gel electrophoresis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The analyses of the total and membrane fractions from bacterial cultures incubated at 37°C identified 68 and 15 proteins, respectively. Since spirochaete clearance in mice is associated with an immunoglobulin M (IgM) and immunoglobulin G3 (IgG3)-mediated response, immunoblot analyses were used to identify the proteins reactive with IgM and IgG3 of gerbil serum against B. duttonii strain Ly. The outcome showed that six proteins (antigen p83/100, membrane-associated protein P66 (P66), flagellar filament outer layer protein, hypothetical protein BDU_412, vlp protein gamma subfamily (γ-Vlp) and flagellin (FlaB)) were identified against IgM, and four (antigen p83/100, P66, γ-Vlp and FlaB) of the six proteins also reacted with IgG3. It is believed that these proteins are immunodominant antigens for the host immune response. Some of these immunogenic proteins might be used as molecular diagnostic tools in the study of relapsing fever in Tanzania.

[Surveillance study on use of over-the-counter drug and health food by school pharmacist for grade-schooler, junior high school student, and high school students].

In recent years, it is necessary to acquire knowledge not only about medicine but also over-the-counter (OTC) drugs and health food for children, because lowering trend in the age of the health hazard by improper use of health food is reported. Therefore, in order to estimate the extent of use of OTC drugs and health food, the school pharmacists administered a questionnaire to students in grade-school (n=123), junior high school (n=303), and high school (n=115) in Fukuyama city. As a result of the questionnaire survey, surprisingly, the usage ratio of OTC drugs and health food showed the most increase in grade-schooler. The trigger of use of health food is "parents' recommendations" in the lower grades, otherwise the ratio of "use by themselves" was increased in the higher grades. Moreover, a remarkable difference was observed by the kinds of use in students with or without exercise. Interestingly, exercise group expected "physical strength" effects than no exercise group. In addition, the ratio of consultation to the pharmacist at the time of purchase of OTC drugs and health food was low in all grade students. In particular, the ratio of consultation to the pharmacist at the time of purchase of health food was very low in high school students. Therefore, to provide accurate information of medicine and health food for students, the school pharmacist should engage not only in routine work but also in positive guidance about OTC drugs and health food in the future.

Absence of transovarial transmission of Borrelia duttonii, a tick-borne relapsing fever agent, by the vector tick Ornithodoros moubata.

We examined the vector competence of the tick, Ornithodoros moubata, using laboratory-reared gerbils as hosts. Transmission of the relapsing fever agent Borrelia duttonii occurred efficiently from infected ticks to uninfected gerbils and from infected gerbils to uninfected ticks. Spirochetes were maintained stably in the ticks for at least 3 months, but they disappeared from the bloodstream of infected gerbils after three episodes of spirochetemia. We also examined transovarial transmission of B. duttonii during the gonotrophic cycle and filial generation. No spirochetes could be detected from the offspring generation of the ticks by culture and polymerase chain reaction (PCR) methods, although spirochetes were still found in the female ticks. The results indicate that, because of the rarity of transovarial infection, the role of transovarial passage of B. duttonii to eggs and larval O. moubata ticks is limited in maintaining B. duttonii. Our findings strongly suggest that B. duttonii is maintained through the O. moubata tick-human transmission cycle in tick-borne relapsing fever endemic areas.

Immunodominant epitope in the C-terminus of a variable major protein in Borrelia duttonii, an agent of tick-borne relapsing fever.

Borrelia duttonii strain Ly was isolated from a child with tick-borne relapsing fever in Tanzania. B. duttonii produces variable major proteins (Vmps), which undergo antigenic variation. We previously reported transcription of the vmpP gene, which is one of the Vmp genes in strain Ly, detected in vitro cultivation. In the current study, we purified the recombinant non-lipidated VmpP protein by affinity chromatography and produced VmpP polyclonal antibodies. Antigenicity of VmpP was examined by Western immunoblot analysis and peptide-based enzyme-linked immunosorbent assays. Antigenic epitopes were shown to comprise five regions interspersed within the VmpP primary amino acid sequence. Synthetic peptides spanning residues of three of five regions, 232-237 (LASIVD), 280-285 (AGGIAL), and 350-355 (KAADQQ), reacted strongly with the VmpP-specific antibody and these residues were identified as epitopes. In particular, the C-terminal domain (KAADQQ) of this protein was immunoreactive. Further research based on our results will promote the development of a recombinant vaccine for B. duttonii infection.

Ile (476), a constituent of di-leucine-based motif of a major lysosomal membrane protein, LGP85/LIMP II, is important for its proper distribution in late endosomes and lysosomes.

Lysosomal membrane glycoprotein termed LGP85 or LIMP II extends a COOH-terminal cytoplasmic tail of R459GQGSMDEGTADERAPLIRT478, in which an L475 I476 sequence lies as a di-leucine-based motif for lysosomal targeting. In the present study, we explored the role of the I476 residue in the localization of LGP85 to the endocytic organelles using two substitution mutants called I476A and I476L in which alanine and leucine are replaced at I476, respectively, and I476R477T478-deleted LGP85 called Delta 476-478. Immunofluorescence analyses showed that I476A and I476L are largely colocalized in intracellular organelles with an endogenous late endosomal and lysosomal marker, LAMP-1, but there were some granules in which staining for the LGP85 mutants was prominent, while Delta 476-478 is detected in LAMP-1-positive and LAMP-1-negative intracellular organelles, and on the cell surface. The subcellular fractionation studies revealed that I476A, I476L, and Delta 476-478 are different from wild-type LGP85 in the distribution of early endosomes, late endosomes, and lysosomes. I476A and I476L are present more in late endosomes than in the densest lysosomes, whereas wild-type LGP85 is mainly lysosomal. Substitution of I476 for A and L differentially modified the ratios of late endosomal to lysosomal LGP85. A major portion of Delta 476-478 resided in the light buoyant density fraction containing plasma membrane and early endosomes. Taken together, these results indicate that the existence of the 476th amino acid residue is essential for localization of LGP85 to late endocytic compartments. The fact that isoleucine but not leucine is in the 476th position is especially of importance in the proper distribution of LGP85 in late endosomes and lysosomes.

The 44-kb linear plasmid molecule in the relapsing fever agent Borrelia duttonii strain Ly serve as a preservation of vmp genes.

Borrelia duttonii strain Ly, a causative agent of relapsing fever, contains a linear one megabase chromosome and 12 linear plasmid molecules. Here we report that the sequence of the 44-kb linear plasmid of strain Ly is found to contain variable major protein (vmp) genes for antigenic variation of relapsing fever borreliae. The determined sequence is of 44,010 bp except for both ends of the molecule. Of 39 open reading frames (ORFs) found in the sequence, 21 ORFs (named vmpA to U) showed moderate similarities with vmp genes for Borrelia hermsii. However, most of the vmp homologues are apparently nonfunctional because of their frameshifts within the sequence and/or absence of promoter and ribosome-binding signals upstream of their genes. RT-PCR experiments using the specific primer for each vmp gene revealed that vmpE, one of the vmp genes, was expressed at the location of the 44-kb plasmid molecule. The result suggests that the plasmid molecule may play a role in the preservation of the serotype switching of vmp genes in a mammalian host.