74 research outputs found
Differential Effects of Methoxy Group on the Interaction of Curcuminoids with Two Major Ligand Binding Sites of Human Serum Albumin
Curcuminoids are a group of compounds with a similar chemical backbone structure but containing different numbers of methoxy groups that have therapeutic potential due to their anti-inflammatory and anti-oxidant properties. They mainly bind to albumin in plasma. These findings influence their body disposition and biological activities. Spectroscopic analysis using site specific probes on human serum albumin (HSA) clearly indicated that curcumin (Cur), demethylcurcumin (Dmc) and bisdemethoxycurcumin (Bdmc) bind to both Site I (sub-site Ia and Ib) and Site II on HSA. At pH 7.4, the binding constants for Site I were relatively comparable between curcuminoids, while the binding constants for Site II at pH 7.4 were increased in order Cur , Dmc , Bdmc. Binding experiments using HSA mutants showed that Trp214 and Arg218 at Site I, and Tyr411 and Arg410 at Site II are involved in the binding of curcuminoids. The molecular docking of all curcuminoids to the Site I pocket showed that curcuminoids stacked with Phe211 and Trp214, and interacted with hydrophobic and aromatic amino acid residues. In contrast, each curcuminoid interacted with Site II in a different manner depending whether a methoxy group was present or absent. A detailed analysis of curcuminoids-albumin interactions would provide valuable information in terms of understanding the pharmacokinetics and the biological activities of this class of compounds
Fructo-oligosaccharides ameliorate steatohepatitis, visceral adiposity, and associated chronic inflammation via increased production of short-chain fatty acids in a mouse model of non-alcoholic steatohepatitis
Background: Non-alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. Within the spectrum of NAFLD, non-alcoholic steatohepatitis (NASH) in combination with hepatic inflammation and fibrosis can lead to liver cirrhosis and hepatocellular carcinoma. Dysbiosis was reported to contribute to NASH pathogenesis. This study aimed to determine the effects of fructo-oligosaccharides (FOS) on steatohepatitis and visceral adiposity in an obese mouse model of NASH.
Methods: Twelve newborn C57BL/6 J male mice were subcutaneously injected with monosodium glutamate (MSG) to induce obesity on a conventional diet. Six mice were also administered 5% FOS via drinking water from 10 weeks of age. At 18 weeks, histological characteristics of the liver and epididymal fat were compared between the groups. Hepatic mRNA expression of lipid metabolism enzymes and SCFA in feces and sera were measured.
Results: Hepatic steatosis, inflammatory cell infiltration, and hepatocyte ballooning in the liver and increased hepatic mRNA expression of fatty acid synthase and glycerol-3-phosphate acyltransferase were observed in the MSG-treated mice. FOS treatment improved the liver pathology and blunted the increases in the mRNA expression levels of lipid metabolism enzymes. In addition, FOS inhibited adipocyte enlargement and formation of crown-like structures and reduced the M1 macrophage frequency in the epididymal fat of the MSG mice (39.4% ± 3.0% vs. 22.8% ± 0.7%; P = 0.001). FOS increased not only the fecal concentrations of n-butyric acid (0.04 ± 0.01 vs. 0.38 ± 0.14 mg/g, P = 0.02), propionic acid (0.09 ± 0.03 vs. 0.42 ± 0.16 mg/g, P = 0.02), and acetic acid (0.65 ± 0.16 vs. 1.48 ± 0.29 mg/g, P = 0.03) but also the serum concentration of propionic acid (3.9 ± 0.5 vs. 8.2 ± 0.5 μmol/L, P = 0.001).
Conclusions: FOS ameliorates steatohepatitis, visceral adiposity, and chronic inflammation by increasing SCFA production
Synthesis of heterocyclic compounds with adamantane-like cage structures consisting of phosphorus, sulfur, and carbon
The synthesis of novel adamantane-like cage compounds consisting of phosphorus, sulfur, and carbon atoms was developed. We examined the reaction of a variety of acetophenone derivatives with P4S10 in refluxing benzene. A novel noradamantane-like cage compound was also synthesized, when the reaction of 2’-methoxyacetophenone with P4S10 was performed in refluxing toluene. In addition, by using the adamantane-like cage compound, 4,4’-dimethoxybenzophenone and N,N-dimethylbenzamide were successfully transformed into the corresponding thioketone (98%) and benzothioamide (89%), respectively
Cys34-cysteinylated human serum albumin is a sensitive plasma marker in oxidative stress-related chronic diseases
The degree of oxidized cysteine (Cys) 34 in human serum albumin (HSA), as determined by high performance liquid chromatography (HPLC), is correlated with oxidative stress related pathological conditions. In order to further characterize the oxidation of Cys34-HSA at the molecular level and to develop a suitable analytical method for a rapid and sensitive clinical laboratory analysis, the use of electrospray ionization time-of-flight mass spectrometer (ESI-TOFMS) was evaluated. A marked increase in the cysteinylation of Cys34 occurs in chronic liver and kidney diseases and diabetes mellitus. A significant positive correlation was observed between the Cys-Cys34-HSA fraction of plasma samples obtained from 229 patients, as determined by ESI-TOFMS, and the degree of oxidized Cys34-HSA determined by HPLC. The Cys-Cys34-HSA fraction was significantly increased with the progression of liver cirrhosis, and was reduced by branched chain amino acids (BCAA) treatment. The changes in the Cys-Cys34-HSA fraction were significantly correlated with the alternations of the plasma levels of advanced oxidized protein products, an oxidative stress marker for proteins. The binding ability of endogenous substances (bilirubin and tryptophan) and drugs (warfarin and diazepam) to HSA purified from chronic liver disease patients were significantly suppressed but significantly improved by BCAA supplementation. Interestingly, the changes in this physiological function of HSA in chronic liver disease were correlated with the Cys-Cys34-HSA fraction. In conclusion, ESI-TOFMS is a suitable high throughput method for the rapid and sensitive quantification of Cys-Cys34-HSA in a large number of samples for evaluating oxidative stress related chronic disease progression or in response to a treatment
Plasmodium berghei Circumvents Immune Responses Induced by Merozoite Surface Protein 1- and Apical Membrane Antigen 1-Based Vaccines
BACKGROUND: Two current leading malaria blood-stage vaccine candidate antigens for Plasmodium falciparum, the C-terminal region of merozoite surface protein 1 (MSP1(19)) and apical membrane antigen 1 (AMA1), have been prioritized because of outstanding protective efficacies achieved in a rodent malaria Plasmodium yoelii model. However, P. falciparum vaccines based on these antigens have had disappointing outcomes in clinical trials. Discrepancies in the vaccine efficacies observed between the P. yoelii model and human clinical trials still remain problematic. METHODOLOGY AND RESULTS: In this study, we assessed the protective efficacies of a series of MSP1(19)- and AMA1-based vaccines using the P. berghei rodent malarial parasite and its transgenic models. Immunization of mice with a baculoviral-based vaccine (BBV) expressing P. falciparum MSP1(19) induced high titers of PfMSP1(19)-specific antibodies that strongly reacted with P. falciparum blood-stage parasites. However, no protection was achieved following lethal challenge with transgenic P. berghei expressing PfMSP1(19) in place of native PbMSP1(19). Similarly, neither P. berghei MSP1(19)- nor AMA1-BBV was effective against P. berghei. In contrast, immunization with P. yoelii MSP1(19)- and AMA1-BBVs provided 100% and 40% protection, respectively, against P. yoelii lethal challenge. Mice that naturally acquired sterile immunity against P. berghei became cross-resistant to P. yoelii, but not vice versa. CONCLUSION: This is the first study to address blood-stage vaccine efficacies using both P. berghei and P. yoelii models at the same time. P. berghei completely circumvents immune responses induced by MSP1(19)- and AMA1-based vaccines, suggesting that P. berghei possesses additional molecules and/or mechanisms that circumvent the host's immune responses to MSP1(19) and AMA1, which are lacking in P. yoelii. Although it is not known whether P. falciparum shares these escape mechanisms with P. berghei, P. berghei and its transgenic models may have potential as useful tools for identifying and evaluating new blood-stage vaccine candidate antigens for P. falciparum
Report on DELP 1986 Cruises in the Northwestern Pacific : Part III: Seismic Structure Revealed by Explosion Experiments
Several interesting features of the crust to upper mantle structure beneath the Northwest Pacific Basin were revealed by a seismic explosion experiment conducted during the DELP cruises in 1986. A large lateral heterogeneity was found both in the configuration of the crust/mantle structure and in the sub-Moho lithosphere. The data from the long range explosion experiment along the WSW-ENE survey line do not support the speculation of large scale anisotropy in this region. The lateral heterogeneities in the crust/mantle structure are indicated by variations of the velocity gradients within oceanic layer 3 and in the velocity transitions from layer 3 to the upper mantle. Wide-angle reflections from inside the sub-Moho lithosphere are clearly recorded with a good signal to noise ratio by small explosions of only 20kg at distances as far as 450km. However, the appearance of these phases differs from place to place. In some places, they are not observed. Lateral heterogeneity of this reflective layer seems to be related to such tectonic features as the fracture zone as well as Nakwe deepsea channel.1986年度夏に実施されたDELPによる北西太平洋海域の発破を利用した地震波構造探査によって,この海域の海底地殻下部から上部マントルの地震波速度構造に関して,いくつかの特徴的な解析結果が得られたので報告する.海洋地殻内部及びモホへの漸移形態のみならず,モホ以深に於ける速度構造にも地域的に非一様性がみられる. WSW-ENE方向の長距離発破測線から得られた記録からは,上部マントルにおける,大規模な速度異方性の存在を支持するような結果は見られなかった.モホ・マントルに関わる地域的非一様性は,海洋地殻第3層に於ける速度の勾配と,モホ面に於ける速度の跳びによって特徴づけられる.モホ以深のリソスフェア内部の何等かの層構造によると思われる広角反射波が,小薬量の発破に依っても450km先まで記録されている.この際だった反射面の存在様式は地震波速度構造の大規模な地域的非一様性と,地磁気によって示されているような破砕帯の存在に深く関係していると考えられる
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