Disease relevance of Sult2a1

• Intragastric injections of heat-stable (ST) toxin of enterotoxigenic Escherichia coli (ETEC) were given to produce fluid accumulation, defined as a gut weight: carcass weight value of > 0.085 [1].
• Hence, in DEN-initiated rats, the effects of promoting regimens of 9-OH-2-FAA or 9-oxo-2-FAA, 15 oral doses at 50 and 100 mumol/kg of body weight, were compared to those of 2-FAA at 50 mumol/kg of body weight and of the vehicle on the activity of N-hydroxy(OH)-2-FAA sulfotransferase (ST), an isozyme of AST IV and AST IV expression and distribution [2].
• Inhibition of androgen action by dehydroepiandrosterone sulfotransferase transfected in PC-3 prostate cancer cells [3].
• Glucose absorption and glucose-facilitated water transport were assessed in rats exposed to semipurified preparations of the heat-labile (LT) and heat-stable (ST) enterotoxins of Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae by in vivo jejunal perfusion of these toxins alone and with varying amounts of glucose [4].
• BACKGROUND & AIMS: Guanylin and heat-stable enterotoxin (STa) stimulate intestinal Cl- secretion via activation of the cystic fibrosis transmembrane regulator (CFTR)-encoded Cl- channel [5].

Psychiatry related information on Sult2a1

• The present findings represent the first analog of the DST in the learned helplessness model of depression [6].
• Elevated ratings of anxiety and agitation in Dexamethasone Suppression Test (DST) nonsuppressors suggest a role for psychological stress in the generation of the hypothalamic-pituitary-adrenal cortical (HPAC) abnormalities characteristic of depression [6].

High impact information on Sult2a1

• Short circuit current (ISC), a measure of Cl- secretion, was increased to a similar extent by STa and by 8-Br-cGMP, a selective activator of cGK, except in distal colon and in monolayers of T84 human colon carcinoma cells in which cGK II was not detected [7].
• CONCLUSIONS: These data provide further evidence for an important role of cGK II in STa-mediated Cl- secretion in native rat intestinal epithelium [8].
• BACKGROUND & AIMS: Escherichia coli heat-stable enterotoxins (STa) provoke electrogenic Cl- secretion in the intestine through a guanosine 3',5'-cyclic monophosphate (cGMP)-dependent signal transduction pathway [8].
• Prostaglandin E2 and 8-bromo-cAMP but not STa/guanylin also transiently increased paracellular permeability [5].
• Therefore, the effect of guanylin/STa and other secretagogues on rat duodenal HCO3- secretion was studied [5].

Chemical compound and disease context of Sult2a1

• The receptor for the heat-stable enterotoxin (ST) from Escherichia coli was solubilized with Lubrol-PX from rat intestinal brush-border membranes and characterized [9].
• Vagotomy inhibits the jejunal fluid secretion activated by luminal ileal Escherichia coli STa in the rat in vivo [10].
• Basal intestinal short circuit current (Isc), a measure of net electrogenic ion movement across the intestinal epithelium, was greater in chronically vitamin E deficient jejuna than controls, as was the electrogenic secretory response to aminophylline and Escherichia coli STa but not to bethanechol [11].
• The mechanism of activation of intestinal guanylate cyclase by Escherichia coli heat-stable enterotoxin (STa) has been studied by using isolated rat intestinal epithelial cells and purified brush border membrane (BBM) preparations [12].
• Guanylyl cyclase C (GCC), the receptor for the Escherichia coli heat-stable enterotoxin (ST), is inhibited by 2-substituted adenine nucleotides in an allosteric fashion [13].

Biological context of Sult2a1

• The deduced amino acid sequence of STa had a homology of 73.7% with that of an SD rat liver senescence marker protein (SMP-2) consisting of 282 amino acid residues [14].
• The nucleotide base sequence of the ST-40 cDNA shared a strong homology of 94.4% with that of ST-20 cDNA encoding a hydroxysteroid ST which had been reported by us [14].
• The cDNA, designated as ST-40, consisted of 1,015 base pairs which had an open reading frame of 852 base pairs encoding the entire rat STa subunit of 284 amino acids [14].
• A remarkable sex difference (female much greater than male) was also observed by immuno-blot analysis in the level of the hydroxysteroid ST protein(s) cross-reacting with the anti-serum in the rat liver cytosols [15].
• In the present study, a female Sprague-Dawley (SD) rat liver cDNA library was screened with rabbit anti-serum raised against hydroxysteroid ST a (STa) purified from female SD rat liver cytosol [15].

Anatomical context of Sult2a1

• Significant intrazonal heterogeneity in STa levels within hepatocytes was also observed, particularly in livers of female rats [16].
• This indicates that APs, unlike STa, do not directly stimulate the colonic epithelial cells but possibly provoke Cl- secretion by release of a neurotransmitter in the submucosa [17].
• Conversely, APs, but not STa, induced a large increase in intracellular cGMP levels in the undifferentiated small intestinal cell lines IEC-6, IEC-18, and INT407 [17].
• CONCLUSIONS: Guanylin and STa stimulate electrogenic HCO3- secretion in rat duodenum, most likely via CFTR Cl- channel activation, but the different relationship for HCO3- to Isc in cGMP-than in cAMP-stimulated anion secretion suggests a different cellular source and/or signaling pathways [5].
• Immunohistochemical detection of cGMP in this tissue provided evidence for a different localization pattern of cells responding with an increase in cGMP levels to STa (colonocytes and goblet cells) or AP (specific cells in the submucosa) in rat proximal colon [17].

Associations of Sult2a1 with chemical compounds

• Here, for the first time, we have demonstrated that AST-IV and STa could be induced in intestine by tamoxifen [18].
• ST-40 is active for all three substrates, whereas ST-20 is mainly active for cortisol [19].
• The two flavonol STs of F. chloraefolia also shared significant sequence similarities with steroid and aryl STs found in animal tissues and with the senescence marker protein 2 isolated from rat liver, suggesting an evolutionary link between plant and animal STs [20].
• Compared to the adult male, SMP-2 mRNA is found in higher amounts in the prepubertal and senescent male rat livers which show relative androgen insensitivity [21].
• In some diethylnitrosamine/phenobarbital-treated rats, a small number of atypical foci were observed, most of them showing enhanced expression of STa and unchanged to moderately increased ATPase activity [22].

Other interactions of Sult2a1

• In addition, ST-20/21 and ST-60 expression reached a peak at 30 days of age in male rats, although ST-40/41 reached its highest value in male rats at 15 days of age [23].
• These results indicate that, whereas the overall hepatic concentrations of these enzymes are clearly sex-dependent, the intralobular distributions of AST IV and STa are characteristic of each particular sulfotransferase [16].
• On the basis of its immunochemical reactivity, SMP-3 (Mr = 19,500) is identified as alpha 2u-globulin while the mRNAs for SMP-1 (Mr = 28,500) and SMP-2 (Mr = 26,300) code for two yet uncharacterized proteins [24].

Analytical, diagnostic and therapeutic context of Sult2a1

• However, ST-20/21 was decreased in both male and female rats by hypophysectomy, and reversed by continuous infusion (female pattern) of growth hormone (GH) [23].
• Molecular cloning and characterization of cDNA for androgen-repressible rat liver protein, SMP-2 [21].
• Northern blot analysis using the 32P-labeled cDNA insert of pSP4a confirms the androgenic repression of the SMP-2 mRNA [21].
• In Western blotting using antibodies raised against the individual ST, hepatic contents of each ST were quantitatively determined [25].
• Next we determined the genetic loci of ST-40 and ST-20 by fluorescence in situ hybridization [26].

References