Cholate activation

The elution profile of cytochrome P-448 (absorption at 418 nm) and epoxide hydratase activity from a sodium cholate-solubi-lized hepatic microsomal preparation (from DBA-treated male skates) applied to a DEAE-cellulose column and eluted with Buffer II is shown in Fig. 3. The void volume of the column contained significant amounts of epoxide hydratase activity. Fractions 40-70 (Fig. 3) were combined, and concentrated. The carbon monoxide difference spectrum, which had an absorption maximum at 448 nm in the induced state, is shown in Fig. 4. This form of the cytochrome (i.e.,... 

C. L. Crowley-Weber, K. Dvorakova, C. Crowley, H. Bernstein, C. Bernstein, H. Garewal and C. M. Payne, Nicotine increases oxidative stress, activates NF-kappaB and GRP78, induces apoptosis and sensitizes cells to genotoxic/xenobiotic stresses by a multiple stress inducer, deoxy-cholate relevance to colon carcinogenesis, Chem. Biol. Interact., 2003, 145(1), 53. 

In the bile cholesterol is kept soluble by fats, phospholipids like lecithin and by bile acids. The important bile acids in human bile are cholic acid, chen-odeoxycholic acid or chenodiol and ursodeoxycholic acid or ursodiol. Bile acids increase bile production. Dehydrocholic acid, a semisynthetic cholate is especially active in this respect. It stimulates the production of bile of low specific gravity and is therefore called a hydrocholeretic drug. Chenodiol and ursodiol but not cholic acid decrease the cholesterol content of bile by reducing cholesterol production and cholesterol secretion. Ursodiol also decreases cholesterol reabsorption. By these actions chenodiol and ursodiol are able to decrease the formation of cholesterolic gallstones and they can promote their dissolution. 

Detergents (26, 41, 46, 96, 97) Optimal concentrations of deoxycholate, cholate, Triton X-100, and cetyltri-methylammonium bromide activate, as does urea. Activation of phosphotransferase > that of phosphohydrolase. Supraoptimal levels inhibit, as do all tested concentrations of sodium lauryl sulfate and Tweens 20 and 80. (See also Lysolecithin, Fatty acids, and Long-chain fatty acyl-CoA esters, above)... 

Phlorizin (7, 13, 16, 17, 89, 101, 146) Inhibits noncompetitively both phosphohydrolase and phosphotransferase activities inhibition of former potentiated by cetrimide and abolished or significantly ameliorated by deoxycholate, cholate, Triton X-100, or digitonin treatment of microsomes. Cetrimide reduces inhibition by phlorizin of phosphohydrolase... 

A number of reports have suggested a relationship between cysteine protease activity and excystment of metacercariae. Cysteine proteases may act alone or in concert with extrinsic host factors such as trypsin in the host gut (Intapan and Maleewong, 2001 Li et al., 2004). In vitro, Paragonimus ohirai metacercarial cysteine protease activity is induced by addition of the bile salt, sodium cholate and parasite... 

Transfersomes, deformable liposomes, were introduced by Cevc et al. in the early 1990s [66-69]. The main components of these systems are phospholipids, a surfactant edge activator (such as sodium cholate), water and sometimes very low concentrations of ethanol (<7%) [66]. Transfersomes are prepared by the same methods as liposomes. The preparation process is usually followed by homogenization, sonication, or other mechanical means to reduce the size of the lipid vesicles. 

Earlier experiments have shown that cholate extracts from transformed lung fibroblasts having only the Mr 52000 subunit of Gs are active in reconstituting hormone-, nucleotide- and fluoride-stimulated adenylyl cyclase activities in cyc membranes [178]. Human erythrocyte Gs, which has only the A/r 42000 a subunit(s) [22,179], also reconstitute(s) these functions. After partial separation, rabbit liver p52 Gs appeared to reconstitute hormone-stimulated activity better than p45 Gs... 

Bile salts are amphiphilic molecules that are surface active and self-associate to form micelles in aqueous solution. They increase corneal permeability by changing the rheological properties of the bilayer [231], A number of bile salts such as deoxy-cholate, taurodeoxycholate, and glycocholate have been tested so far, and it was suggested, that a difference in their physicochemical properties (solubilizing activity, lipophilicity, Ca2+ sequestration capacity) is probably related to their performance as permeability-enhancing agents [36]. 

Baugh and King (43, 43a) have recently reported the isolation of a preparation from mitochondria with high NADH-ferricyanide and NADH-Q reductase activities (Table III). As compared to complex I, the preparation contains 20-25% less FMN, but more iron and labile sulfide, the ratio of FMN nonheme iron labile sulfide being 1 28 28. The enzyme is isolated from Keilin-Hartree particles (prepared from beef heart mitochondria) after treatment with Triton X-lOO and subsequently with cholate. It is claimed to be water soluble and free of phospholipids. However, satisfactory analytical data for the absence of lipid (e.g., phos-... 

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