In vivo and in silico anti-inflammatory mechanism of action of the semisynthetic (−)-cubebin derivatives (−)-hinokinin and (−)-O-benzylcubebin

(?)-Cubebin (CUB), isolated from seeds of Piper cubeba, was used as starting material to obtain the derivatives (?)-hinokinin (HK) and (?)-O-benzyl cubebin (OBZ). Using paw edema as the experimental model and different chemical mediators (prostaglandin and dextran), it was observed that both derivatives were active in comparison with both negative (5% Tween® 80 in saline) and positive (indomethacin) controls. The highest reduction in the prostaglandin-induced edema was achieved by OBZ (66.0%), while HK caused a 59.2% reduction. Nonetheless, the dextran-induced paw edema was not significantly reduced by either of the derivatives (HK or OBZ), which inhibited edema formation by 18.3% and 3.5%, respectively, in contrast with the positive control, cyproheptadine, which reduced the edema by 56.0%. The docking analysis showed that OBZ presented the most stable ligand-receptor (COX-2 – cyclooxygenase-2) interaction in comparison with CUB and HK.     

Metabolism of (−)-deprenyl and PF-(−)-deprenyl in brain after central and peripheral administration

We examined the cerebral metabolism of L-deprenyl and its fluoro-derivative pF-deprenyl, assaying the parent compounds, their metabolites desmethyl deprenyl, L-amphetamine, and L-methamphetamine, and the fluoro analogs of these metabolites. We compared the levels of the metabolites after subcutaneous injection with those after intracerebral administration (via microdialysis) of the parent compounds. The assay of the parent compounds and their metabolites was by GC-MS measurement of the components of brain microdialysate samples. After their subcutaneous administration, deprenyl and F-deprenyl rapidly entered the brain and then their concentration decreased, with an approximate half-life of 4.5 h. After the intracerebral administration the diffusion from the site of administration was minor. A small fraction (a few percent) of the intracerebrally administered deprenyl was metabolized in situ in the brain possibly by a nonenzymatic process. Metabolism of pF-deprenyl was somewhat more rapid. The higher cerebral levels of metabolites after the subcutaneous administration indicate their exogenous origin—metabolism of parent compounds in the periphery and penetration of the brain by the metabolites.     

(−)-Allo-pertusaric acid and (−)-dihydropertusaric acid from the lichen Pertusaria albescens

The structures of two γ-lactone carboxylic acids from the lichen Pertusaria albescens, (−)-allo-pertusaric acid and (−)dihydropertusaric acid, have been elucidated by spectroscopic and chemical methods. From P. ophthalmiza, taraxerone and a mixture of long chain aliphatic alcohols and fatty acids have been isolated.     

Production of d(−)-lactate from sucrose and molasses

Escherichia coli W3110 derivatives, strains SZ63 and SZ85, were previously engineered to produce optically pure D(-) and L(+)-lactate from hexose and pentose sugars. To expand the substrate range, a cluster of sucrose genes (cscR' cscA cscKB) was cloned and characterized from E. coli KO11. The resulting plasmid was functionally expressed in SZ63 but was unstable in SZ85. Over 500 mM D(-)-lactate was produced from sucrose and from molasses by SZ63(pLOI3501).     

Haplomyrtin and (−)-haplomyrfolin: two lignans from haplophyllum myrtifolium

Haplomyrtin, a new 1-aryl-2-3-naphthalide lignan, and (−)-haplomyrfolin, a new dibenzylbutyrolactone lignan, have been obtained from Turkish Haplophyllum myrtifolium.     

The neolignans (−)-carinatone and carinatin from Virola carinata

From the bark of Virola carinata two neolignans have been isolated: (?)-carcinatone, [(2S)-1-(3′,4′-dimethoxyphenyl)-2-(3″-allyl-5″-methoxy-6″-hydroxyphenyl) propanone] and carinatin, [5-allyl-7-methoxy-3-methyl-2-(3′,4′-dimethoxyphenyl)benzofuran].     

(−)-Epilamprolobine and its N-oxide,lupin alkaloids from Sophora tomentosa

From the fresh leaves of Sophora tomentosa, three new lupin alkaloids, (?)-epilamprolobine, (+)-epilamprolobine N-oxide and 5-(3′-methoxycarbonylbutyroyl)aminomethyl-trans-quinolizidine N-oxide, have further been isolated along with (+)-matrine, (+)-matrine N-oxide, (+)-sophocarpine N-oxide, (?)-anagyrine, (?)- baptifoline, (?)-cytisine, (?)-N-methylcytisine, (?)-N-formylcytisine, (?)-N-acetylcytisine and (±)-ammodendrine. The absolute configurations of (+)-epilamprolobine N-oxide (1R:5R:6S) and (?)-epilamprolobine (5R:6S) have also been established by spectroscopic data and by comparison with synthetic (+)-epilamprolobine (5S:6R)derived from (?)-lupinine (5R:6R). (?)-Epilamprolobine is a diastereomer of (+)-lamprolobine (5R:6R) in Lamprolobium fruticosum and 5-(3′-methoxycarbonylbutyroyl) aminomethyl-trans-quinolizidine N-oxide is presumed to be an artefact. A biosynthetic pathway for the formation of (?)-epilamprolobine is also proposed.     

Pharmacophore-based design and discovery of (−)-meptazinol carbamates as dual modulators of cholinesterase and amyloidogenesis

Multifunctional carbamate-type acetylcholinesterase (AChE) inhibitors with anti-amyloidogenic properties like phenserine are potential therapeutic agents for Alzheimer’s disease (AD). We reported here the design of new carbamates using pharmacophore model strategy to modulate both cholinesterase and amyloidogenesis. A five-feature pharmacophore model was generated based on 25 carbamate-type training set compounds. (?)-Meptazinol carbamates that superimposed well upon the model were designed and synthesized, which exhibited nanomolar AChE inhibitory potency and good anti-amyloidogenic properties in in vitro test. The phenylcarbamate 43 was highly potent (IC₅₀ 31.6?nM) and slightly selective for AChE, and showed low acute toxicity. In enzyme kinetics assay, 43 exhibited uncompetitive inhibition and reacted by pseudo-irreversible mechanism. 43 also showed amyloid-β (Aβ) lowering effects (51.9% decrease of Aβ₄₂) superior to phenserine (31% decrease of total Aβ) in SH-SY5Y-APP₆₉₅ cells at 50?µM. The dual actions of 43 on cholinergic and amyloidogenic pathways indicated potential uses as symptomatic and disease-modifying agents.     

(−)-N-Formylanonaine from Michelia alba as a human tyrosinase inhibitor and antioxidant

Tyrosinase is the first and rate limiting enzyme in the synthesis of melanin pigments for coloring hair, skin, and eyes. As reported in this study, a natural product, (?)-N-formylanonaine isolated from the leaves of Michelia alba D.C. (Magnolianceae), was found to inhibit mushroom tyrosinase with an IC₅₀ of 74.3 μM and to have tyrosinase and melanin reducing activities in human epidermal melanocytes without apparent cytotoxicity to human cells, superior to the known tyrosinase inhibitors, such as kojic acid and 1-phenyl-2-thiourea (PTU). Based on homology modeling, the compound binds the active site by coordinating with two Cu²⁺ ions. In addition, the compound had antioxidation activities in tests for scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power, and chelating metal ions. To our knowledge, this is the first study to reveal the bioactivities of (?)-N-formylanonaine from this plant species.     

Purification and partial characterization ofd-(−)-lactate dehydrogenase fromLactobacillus helveticus CNRZ 32

Summary d-(–)-Lactate dehydrogenase (LDH) was purified to homogeneity from a cell-free extract ofLactobacillus helveticus CNRZ 32. The native enzyme was determined to have a molecular weight of 152 000 and consisted of four identical subunits of 38 000. This enzyme was NAD dependent fructose 1,6-diphosphate (FDP) and ATP independent. It was most active on pyruvate followed by -hydroxypyruvate as substrates. TheK _m values for pyruvate andd-(–)-lactate were 0.64 and 68.42 mM respectively, indicating that the enzyme has a higher affinity for pyruvate. The enzyme activity was completely inhibited byp-chloromercuribenzoate (1 mM) and partially by iodoacetate, suggesting the involvement of the sulfhydryl group (-SH) in catalysis. Optima for activity by the purified enzyme were pH 4.0 and 50–60°C. Limited inhibition ofd-(–)-LDH was observed with several divalent cations. Additionally, HgCl₂ was observed to strongly inhibit enzyme activity. The purified enzyme was not affected by dithiothreitol or any of the metal chelating agents examined.     

Biotransformation of (−)-epicatechin, (+)-epicatechin, (−)-catechin,and (+)-catechin by intestinal bacteria involved in isoflavone metabolism

Isoflavone-metabolizing bacteria, Adlercreutzia equolifaciens, Asaccharobacter celatus, Slackia equolifaciens, and Slackia isoflavoniconvertens catalyzed C-ring cleavage of (–)-epicatechin and (+)-catechin, (+)-epicatechin, and (–)-catechin in varying degrees. The cleaving abilities of (–)-epicatechin and (+)-catechin were enhanced by hydrogen, except (+)-catechin cleavage by S. equolifaciens, which was not accelerated. (?)-Catechin cleavage by Ad. equolifaciens was remarkably accelerated by hydrogen.     

Identification and characterization of a novel (−)-vibo-quercitol 1-dehydrogenase from Burkholderia terrae suitable for production of (−)-vibo-quercitol from 2-deoxy-scyllo-inosose

Applied Microbiology and Biotechnology - (−)-vibo-Quercitol is a deoxyinositol (1l-1,2,4/3,5-cyclohexanepentol) that naturally occurs in oak species, honeydew honey, wines aged in oak...     

Synthesis of (−)‐DAPD

A new synthesis of (?)‐DAPD, suitable for large scale development, is described.     

(−)-Epingaione from Bontia daphnoides

(−)-Epingaione has been isolated as the major lipophilic metabolite of Bontia daphnoides, the only member of the Myoporaceae found in the West Indies.     

Different responses of CR(−) and CR(+) B cells to LPS stimulation

Proliferative response of B cells with or without CR [CR(+) or CR(?) B cells] was compared in their polyclonal response when they were stimulated with lipopolysaccharide (LPS). CR(+) B cells responded better in proliferation and more poorly in polyclonal antibody formation than did CR(?) B cells. The dissociation between proliferation and antibody formation in LPS response was not due to the shift of the time kinetics nor the exhaustion of the culture medium. T cells and macrophages did not take part in the dissociation, since macrophage depletion from nu/nu mouse spleen cells could not modify the dissociation. The polyclonal antibody response of CR(?) B cells was more resistant to irradiation than that of CR(+) B cells. These results suggest that among LPS-responsive B cells there are CR(?) B-cell subset(s) more mature than CR(+) B cells.     

Semi-preparative chromatographic purification of the enantiomers S-(−)-amlodipine and R-(+)-amlodipine

Pharmacokinetic studies of optically pure compounds after single enantiomer administration are becoming increasingly important. The process of racemization in vivo can diminish all expected advantages of single enantiomer treatment. Amlodipine, one of the calcium channel blockers, currently used in therapy as a racemate, is one of such drugs under study. In order to administer single enantiomers of amlodipine to healthy volunteers both were chromatographically purified and characterised. The two optical isomers of amlodipine, active S-(−)- and non-active R-(+)-amlodipine, were purified using chromatographic procedure adopted from the analytical separation. Enantiomers were successfully converted to benzenesulphonic salt without any racemization. All semi-preparative purifications were monitored with complementary analytical methods, HPLC and CE, along with the determination of optical activity so that the final product was sufficiently defined for further in vivo studies. The analytical method developed for the determination of plasma concentrations of each enantiomer of amlodipine in these studies is also briefly described.     

Proteomic analysis of CD44(+) and CD44(−) gastric cancer cells

CD44 is a cell surface protein and it is widely used as a cancer stem cell marker in various cancer types including gastric cancer. We conducted proteomic analysis in CD44(+) and CD44(?) gastric cancer cells to understand characteristics of CD44(+) and CD44(?) cells. In the present study, we sorted cells from the gastric cancer cell line MKN45 according to CD44 expression to separate out CD44(+) and CD44(?) cells. And we conducted RT-PCR to identify mRNA expression of cancer stem cell markers in CD44(+) and CD44(?) cells. Cancer stem cell markers showed upregulated expression in CD44(+) cells. Next, we performed two-dimensional electrophoresis analysis to determine the differential expression pattern of proteins in each group; control, CD44(+), and CD44(?) MKN45 cells. We found a total of 113 spots that varied in expression between CD44(+) and CD44(?) cells, and subjected 20 of those protein spots to MALDI-MS. We selected the three proteins (HSPA8; heat shock cognate 71 kDa protein isoform 1, ezrin, α-enolase) upregulated in CD44(+) cells than CD44(?) cells and one protein (prohibitin) showed increased expression in CD44(?) cells. We validated the protein expression levels of four selected proteins by Western blot. We suggest that our study could be a helpful background to study CD44(+) cancer stem-like cells and differences between CD44(+) and CD44(?) cells in gastric cancer.     

Isolation and characterization of rat intestinal bacteria involved in biotransformation of (−)-epigallocatechin

Two intestinal bacterial strains MT4s-5 and MT42 involved in the degradation of (?)-epigallocatechin (EGC) were isolated from rat feces. Strain MT4s-5 was tentatively identified as Adlercreutzia equolifaciens. This strain converted EGC into not only 1-(3, 4, 5-trihydroxyphenyl)-3-(2, 4, 6-trihydroxyphenyl)propan-2-ol (1), but also 1-(3, 5-dihydroxyphenyl)-3-(2, 4, 6-trihydroxyphenyl)propan-2-ol (2), and 4′-dehydroxylated EGC (7). Type strain (JCM 9979) of Eggerthella lenta was also found to convert EGC into 1. Strain MT42 was identified as Flavonifractor plautii and converted 1 into 4-hydroxy-5-(3, 4, 5-trihydroxyphenyl)valeric acid (3) and 5-(3, 4, 5-trihydroxyphenyl)-γ-valerolactone (4) simultaneously. Strain MT42 also converted 2 into 4-hydroxy-5-(3, 5-dihydroxyphenyl)valeric acid (5), and 5-(3, 5-dihydroxyphenyl)-γ-valerolactone (6). Furthermore, F. plautii strains ATCC 29863 and ATCC 49531 were found to catalyze the same reactions as strain MT42. Interestingly, formation of 2 from EGC by strain MT4s-5 occurred rapidly in the presence of hydrogen supplied by syntrophic bacteria. Strain JCM 9979 also formed 2 in the presence of the hydrogen or formate. Strain MT4s-5 converted 1, 3, and 4 to 2, 5, and 6, respectively, and the conversion was stimulated by hydrogen, whereas strain JCM 9979 could catalyze the conversion only in the presence of hydrogen or formate. On the basis of the above results together with previous reports, the principal metabolic pathway of EGC and EGCg by catechin-degrading bacteria in gut tract is proposed.