Purification, identification and phosphorylation of annexin I from rat liver mitochondria.

Annexin was purified from rat liver mitochondria to an apparent homogeneity with a molecular weight of 35 kDa as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified mitochondrial annexin (AXmito) was identified as annexin I by an immunoblot analysis using anti-annexin I antibody. The inhibitory effect of AXmito I on porcine pancreatic phospholipase A2 activity was as potent as that of bovine lung annexin I. The presence of annexin I in mitochondria was confirmed by an electron-microscopic study. AXmito I was shown to be phosphorylated by intrinsic protein tyrosine kinases on its tyrosine residues. This annexin was also phosphorylated by protein kinase C.</p

The expression of Ca2+/calmodulin-dependent protein kinase I in rat retina is regulated by light stimulation

AbstractCa2+/calmodulin-dependent protein kinase I (CaM-kinase I) in rat retina was analyzed by immunohistochemical analysis, Western blot analysis and kinase activity assay. Western blot analysis revealed two immunoreactive bands similar to those detected in the brain. Developmental studies revealed that CaM-kinase I expression increased in accordance with postnatal development. Expression of CaM-kinase I in the retinas of rats raised in the complete darkness markedly decreased. CaM-kinase I activity assay supported these findings. Synapsin I was shown to be a possible intrinsic substrate of CaM-kinase I in rat retina. These results elucidated that CaM-kinase I is expressed in the retina and may play an important role in the retinal functions and that the expression of CaM-kinase I is regulated by light stimulation

New methyl threonolactones and pyroglutamates of Spilanthes acmella

[Objective] Spilanthes acmella is a medicinal plant that distributed in the tropical and subtropical regions with rich source of therapeutic and medicinal constituents. The main constituents, "spilanthol” and “ acmellonate”, are used to reduce the pain associated with toothaches and induce saliva secretion. It is also used traditionally as treatment of rheumatism, tongue paralysis, antipyretic, sore throat, and gum infections [1]. It contains phytosterols, essential oils, sesquiterpenes, α and β-bisabolenes and cadinenes, flavonoid glucoside and a mixture of long chain hydrocarbons. In recent years, other bioactive metabolites have been isolated as vanillic acid, trans-ferulic acid, trans-isofcrulic acid, scopolelin, 3-acetylaleuritolic acid and β-sitostenone[2], [Methods] The aerial parts of Spilanthes acmella were collected in Purwodadi, Indonesia, then extracted with methanol. The obtained methanol extract was concentrated and partitioned with n-hexane, ethyl acetate, and 1-butanol. [Results] On investigation of the 1-butanol layer of this plant, a new methyl threonolactone glucoside (1), a new methyl threonolactone fructofuranoside (2) and two new pyroglutamates (3, 4) along with 2-C-methyl-D-threono-1,4-lactone (5), 2-deoxy-D-ribono-1,4-lactone (6), methylpyroglutamate (7), dendranthemoside A (8), dendranthemoside B (9), ampelopsisionoside (10),icariside B2 (11), benzyl-α-L-arabinopyranosyl-( l-6)-β-D-glucopyranoside (12) and chicoriin (13) were isolated by various chromatographic techniques such as silica gel, ODS column chromatography and HPLC. The structures of these compounds were determined as follows by spectrometric analysis (UV, IR, ID- and 2D-NMR, and HR-ESI-MS)

New Isolinariins C, D and E, Flavonoid Glycosides from Linaria japonica

Three new flavonoid glycosides named isolinariins C, D and E (1–3), two known flavonoid glycosides (4,5) and three known flavonoids (6–8) were isolated from the whole plant of Linaria japonica. The structures of these compounds were determined mainly by spectroscopic analyses. The bioactivities of these isolated compounds were evaluated for their inhibitory activities against human cell line A549, collagenase, and advanced glycation end product (AGE) formation. Among the isolated compounds, isolinariins C, D and E (1, 2 and 3) showed inhibition toward AGE formation (IC50 values of 34.8, 35.0 and 19.5 µM, respectively). And linariin (4), pectolinarin (5) and luteolin (8) were found to be active against collagenase with IC50 values of 79.4, 78.6 and 40.5 µM, respectively, without significant cytotoxicity at these concentrations

Effect of Peripheral 5-HT on Glucose and Lipid Metabolism in Wether Sheep

In mice, peripheral 5-HT induces an increase in the plasma concentrations of glucose, insulin and bile acids, and a decrease in plasma triglyceride, NEFA and cholesterol concentrations. However, given the unique characteristics of the metabolism of ruminants relative to monogastric animals, the physiological role of peripheral 5-HT on glucose and lipid metabolism in sheep remains to be established. Therefore, in this study, we investigated the effect of 5-HT on the circulating concentrations of metabolites and insulin using five 5-HT receptor (5HTR) antagonists in sheep. After fasting for 24 h, sheep were intravenously injected with 5-HT, following which-, plasma glucose, insulin, triglyceride and NEFA concentrations were significantly elevated. In contrast, 5-HT did not affect the plasma cholesterol concentration, and it induced a decrease in bile acid concentrations. Increases in plasma glucose and insulin concentrations induced by 5-HT were attenuated by pre-treatment with Methysergide, a 5HTR 1, 2 and 7 antagonist. Additionally, decreased plasma bile acid concentrations induced by 5-HT were blocked by pre-treatment with Ketanserin, a 5HTR 2A antagonist. However, none of the 5HTR antagonists inhibited the increase in plasma triglyceride and NEFA levels induced by 5-HT. On the other hand, mRNA expressions of 5HTR1D and 1E were observed in the liver, pancreas and skeletal muscle. These results suggest that there are a number of differences in the physiological functions of peripheral 5-HT with respect to lipid metabolism between mice and sheep, though its effect on glucose metabolism appears to be similar between these species