RESUMEN
We have previously shown glycosphingolipids of Ascaris suum to have phosphorylcholine (PC) and non-PC immunomodulatory moieties. In the present study we further investigated the nature of the immunomodulatory moieties by employing three synthetic glycosphingolipids each possessing features of the original molecule to examine effects on macrophage and dendritic cell (DC) cytokine production and surface co-stimulatory molecule expression. Compound 2, which lacked PC but contained ceramide, had no effect on either macrophages or DCs. Surprisingly however, Compound 1, which contained PC and hence arguably most resembled the native material, had, with the exception of a small increase in surface antigen expression, no immunomodulatory properties. Conversely, Compound 3, which contained PC but was otherwise least like the native molecule, demonstrated a number of effects on both macrophages and DCs, including induction of Th-1/pro-inflammatory cytokines, inhibition of such cytokines induced by IFN-gamma/LPS and increased expression of co-stimulatory molecules. Taken together these results indicate: (i) that although PC is an immunomodulatory component of the native molecule other structural feature are necessary to allow it to act; (ii) that carbohydrate rather than ceramide is likely to represent a non-PC immunomodulatory moiety; and (iii) that synthetic PC-containing molecules have the potential to act as immunomodulatory drugs.
Asunto(s)
Ascaris suum/inmunología , Células Dendríticas/inmunología , Glicoesfingolípidos/inmunología , Factores Inmunológicos/farmacología , Macrófagos/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Ascaris suum/química , Conformación de Carbohidratos , Secuencia de Carbohidratos , Ceramidas/inmunología , Células Dendríticas/efectos de los fármacos , Glicoesfingolípidos/farmacología , Factores Inmunológicos/inmunología , Interleucina-12/biosíntesis , Interleucina-12/inmunología , Subunidad p40 de la Interleucina-12 , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Fosforilcolina/inmunología , Subunidades de Proteína/biosíntesis , Subunidades de Proteína/inmunología , Células TH1/efectos de los fármacos , Células TH1/inmunología , Factor de Necrosis Tumoral alfa/biosíntesis , Regulación hacia ArribaRESUMEN
The allelic compositions of high- and low-molecular-weight subunits of glutenins (HMW-GS and LMW-GS) among European spelt ( Triticum spelta L.) and related hexaploid and tetraploid Triticum species were investigated by one- and two-dimensional polyacrylamide-gel electrophoresis (PAGE) and capillary electrophoresis (CE). A total of seven novel glutenin alleles (designated A1a*, B1d*, B1g*, B1f*, B1j*, D1a* at Glu-1 and A3h at the Glu-3 loci, respectively) in European spelt wheat were detected by SDS-PAGE, which were confirmed further by employing A-PAGE and CE methods. Particularly, two HMW-GS alleles, Glu-B1d* coding the subunits 6.1 and 22.1, and Glu-B1f* coding the subunits 13 and 22*, were found to occur in European spelt with frequencies of 32.34% and 5.11%, respectively. These two alleles were present in cultivated emmer (Triticum dicoccum), but they were not observed in bread wheat (Triticum aestivum L.). The allele Glu-B1g* coding for 13* and 19* subunits found in spelt wheat was also detected in club wheat (Triticum compactum L.). Additionally, two alleles coding for LMW-GS, Glu-A3h and Glu-B3d, occurred with high frequencies in spelt, club and cultivated emmer wheat, whereas these were not found or present with very low frequencies in bread wheat. Our results strongly support the secondary origin hypothesis, namely European spelt wheat originated from hybridization between cultivated emmer and club wheat. This is also confirmed experimentally by the artificial synthesis of spelt through crossing between old European emmer wheat, T. dicoccum and club wheat, T. compactum.
Asunto(s)
Glútenes/análogos & derivados , Glútenes/genética , Ploidias , Triticum/genética , Alelos , Cruzamientos Genéticos , Electroforesis en Gel de Poliacrilamida , Europa (Continente) , Marcadores Genéticos , Peso Molecular , Proteínas de Plantas/genética , Subunidades de ProteínaRESUMEN
Homoeoalleles of Ncc confer nucleus-cytoplasm (NC) compatibility on NC hybrids of wheat with the D plasmon of Aegilops squarrosa. To dissect the chromosomal region containing Ncc, a RAPD marker linked to the Ncc-tmplA locus, which is located on chromosome 1A of T timopheevi, was sequenced and converted to a PCR-based sequence-tagged-site (STS) marker. Five single nucleotide polymorphisms (SNPs) between T timopheevi and T turgidum. were detected in a 509-bp genomic DNA fragment. Based on the SNPs, the STS alleles in 164 accessions from emmer wheat, timopheevi wheat and two einkorn wheats, T. urartu and T. boeoticum were surveyed by PCR-RFLP analysis. The sequence comparisons and PCR-RFLP analyses revealed nine alleles based on six SNPs. These SNPs were highly conserved within each group of wheat, and all groups could be distinguished by particular combinations of the SNPs. All accessions of T. urartu had one unique STS allele as compared with the others. Our results indicate that the SNPs in the STS marker linked to the Ncc-tmplA locus would be informative for studies of the differentiation of chromosome 1A in wheat.
Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Triticum/genética , Alelos , Secuencia de Bases , Biomarcadores , Núcleo Celular/genética , Citoplasma/genética , Genes de Plantas , Datos de Secuencia Molecular , Ploidias , Mapeo RestrictivoRESUMEN
A nuclear gene, Ncc-tmp1A, of Triticum timopheevii is required for the nucleus-cytoplasm (NC) compatibility in tetraploid NC hybrids with the cytoplasm of Aegilops squarrosa. A euploid NC hybrid of T. durum was previously produced by introgressing the gene from chromosome 1A of T. timopheevii. To examine the possible presence of a functional homoeoallele in the G genome of T. timopheevii, segregation of seed viability was studied as a marker phenotype in BC1s involving the two types of NC hybrids, (Ae. squarrosa)-T. timopheevii and (Ae. squarrosa)-T. turgidum. The result of these test crosses suggested that the G genome possesses a functional homoeoallele Ncc-tmp1G. Segregation of two RAPD (random amplified polymorphic DNA) markers that were closely linked to Ncc-tmp1A was further studied among the viable BC1s obtained from a test cross of (Ae. squarrosa)-T. timopheevii x T. turgidum. Some viable BC1 segregants without the markers were obtained, suggesting a limited degree of transmission of chromosome 1G carrying Ncc-tmp1G. However, a similar RAPD analysis of BC1s obtained after backcrosses of reciprocal F1s of T. timopheevii/T. turgidum with T. turgidum showed random marker segregation. Thus, it was concluded that Ncc-tmp1A is not required for compatibility with its own cytoplasm. Southern blot analysis of the euploid NC hybrid using RFLP (restriction fragment length polymorphism) markers on the homologous group 1 chromosomes showed that Ncc-tmp1A locates in the centromeric region.
Asunto(s)
Núcleo Celular/genética , Citoplasma/genética , Genes de Plantas , Ploidias , Poaceae/genética , Triticum/genética , Alelos , Cruzamientos Genéticos , Genotipo , Meiosis , Técnica del ADN Polimorfo Amplificado AleatorioRESUMEN
Squalene synthase (SQS; EC 2.5.1.21) plays an important role in the cholesterol biosynthetic pathway. We discovered ER-28448, 5-(N-[2-butenyl-3-(2-methoxyphenyl)]-N-methylamino)-1, 1-penthylidenebis(phosphonic acid) trisodium salt, as a potent and selective inhibitor of SQS. ER-28448 inhibited SQS in rat liver microsome with an IC(50) value of 3.6 nm. We also prepared ER-27856, the tripivaloyloxymethyl ester prodrug of ER-28448. Although less active than ER-28448 in a liver microsome assay, ER-27856 more potently inhibited cholesterol biosynthesis in rat hepatocytes; and ER-27856 orally inhibited de novo cholesterol biosynthesis in Sprague-Dawley rats, with an ED(50) value of 1.6 mg/kg. In HepG2 cells, ER-27856 upregulated low density lipoprotein receptor activity to 2.1 times that of control. A time-course study indicated that the inhibitory effect of ER-27856 on cholesterol biosynthesis in rats continued for up to 8 h. In a study of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (HMGRIs), atorvastatin actively suppressed cholesterol biosynthesis for 8 h, whereas the effect of pravastatin and simvastatin diminished at 4 and 8 h, respectively. In rhesus monkeys, 4 days of oral administration of ER-27856 lowered plasma total cholesterol (TCHO) more potently than did these HMGRIs. Whereas atorvastatin significantly elevated plasma alanine aminotransferase, a marker of hepatotoxicity, to 3.7 times at 100 mg/kg, ER-27856 increased the level only 1.4 times at 10 mg/kg, at which doses the hypocholesterolemic effect was equivalent. During 28 days of administration, ER-27856 reduced TCHO and non-high density lipoprotein (non-HDL) cholesterol by 72 and 95%, respectively. These results demonstrate that ER-27856 had more potent hypocholesterolemic activity and less hepatotoxic effect than HMGRIs. ER-27856 may contribute to the treatment of hypercholesterolemic patients.
Asunto(s)
Anticolesterolemiantes/farmacología , Colesterol/sangre , Difosfonatos/farmacología , Farnesil Difosfato Farnesil Transferasa/antagonistas & inhibidores , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Alanina Transaminasa/sangre , Animales , Atorvastatina , Difosfonatos/efectos adversos , Relación Dosis-Respuesta a Droga , Ácidos Heptanoicos/farmacología , Hidroximetilglutaril-CoA Reductasas/efectos de los fármacos , Hígado/citología , Hígado/efectos de los fármacos , Hígado/metabolismo , Macaca mulatta , Masculino , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Profármacos/farmacología , Pirroles/farmacología , Ratas , Ratas Sprague-DawleyRESUMEN
An unidentified bacterial strain, SCRC-21406, isolated from the intestine of a marine fish, Glossanodon semifasciatus, produced docosahexaenoic acid at 23% (mol/mol) [= 28% (w/w)] of total fatty acids in a medium containing 0.5% (wt/vol) peptone and 0.1% (wt/vol) yeast extract at 12 degrees C under atmospheric pressure. The cell yield was 0.43 g/L. The major lipids of the strain were phosphatidylethanolamine and phophatidylglycerol. Docosahexaenoic acid was localized at the sn-2 positions of both phospholipids. The amounts of polyunsaturated fatty acids other than docosahexaenoic acid were extremely small [< 3% (mol/mol)]. Monounsaturated fatty acids of the cis-7, cis-9 and cis-11 types were detected.
Asunto(s)
Bacterias/química , Ácidos Docosahexaenoicos/metabolismo , Ácidos Grasos/análisis , Lípidos/análisis , Animales , Bacterias/metabolismo , Ácidos Grasos/química , Peces/microbiología , Japón , Lípidos/química , Espectrometría de Masas , Conformación Molecular , Fosfolípidos/análisis , Fosfolípidos/química , EspectrofotometríaRESUMEN
Alien cytoplasms cause a wide range of phenotypic alterations in the nucleus-cytoplasm (NC) hybrids in the Triticeae. Nuclear genomes of timopheevii wheat (Triticum timopheevii and Triticum araraticum) are fully compatible with the cytoplasm of Aegilops squarrosa, while those of a majority of emmer or durum wheat cultivars and more than half the wild emmer wheats are incompatible, and a maternal 1D chromosome is required to restore seed viability and male fertility in the NC hybrids. A euploid NC hybrid of Triticum durum cv. Langdon with Ae. squarrosa cytoplasm produced by introgressing the NC compatibility (Ncc) gene from T. timopheevii was used to identify random amplified polymorphic DNA (RAPD) markers linked to it. After a survey of 200 random decamer primers, four markers were selected, all of which were completely linked in 64 individuals of a SB8 mapping population. One marker was derived from a single locus, while three others were from interspersed repetitive sequences. Also, the hybrid chromosomes and those of the parental T. durum had identical C-banding patterns. RAPD-PCR analysis of 65 accessions from wild and cultivated tetraploid wheat species showed the exclusive presence of the markers in timopheevii wheat. In conclusion, the chromosomal region flanking Ncc of T. timopheevii is highly conserved in the genome of this group of tetraploid wheats.
RESUMEN
E5324, n-butyl-N'-[2-[3-(5-ethyl-4-phenyl-1H-imidazol-1-yl)propoxy]-6- methylphenyl]urea, a novel and potent inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), was evaluated for its anti-atherosclerotic and lipid-lowering effects in Watanabe heritable hyperlipidemic (WHHL) rabbits. At 3 months of age, 40 male WHHL rabbits were divided into 4 groups. The rabbits were fed a standard rabbit chow (control group), or standard rabbit chow containing E5324 (0.1% or 0.02%) or 1% probucol for 16 weeks. Even the high dose of E5324 did not lower the plasma total cholesterol levels throughout the experiment. Probucol slightly reduced the plasma cholesterol levels, and showed anti-atherosclerotic activity, i.e., reductions of atherosclerotic plaque formation and cholesterol content in the aorta. Although E5324 did not lower plasma cholesterol, atherosclerotic plaque formation in the aortic arch and thoracic aorta was reduced (by about 34% and 41%, respectively, at the high dose; P < 0.05). Cholesterol content in the aortic arch and thoracic aorta was also reduced (by about 59% and 62% at the high dose, respectively) compared with the control. These results suggest that E5324 acts directly on the arterial wall through ACAT inhibition, and prevents the progression of atherosclerosis in WHHL rabbits.
Asunto(s)
Arteriosclerosis/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Hiperlipidemias/enzimología , Compuestos de Fenilurea/farmacología , Esterol O-Aciltransferasa/antagonistas & inhibidores , Análisis de Varianza , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/metabolismo , Aorta Torácica/patología , Arteriosclerosis/enzimología , Arteriosclerosis/etiología , Colesterol/metabolismo , Cromatografía en Capa Delgada , Dieta , Modelos Animales de Enfermedad , Hiperlipidemias/complicaciones , Hiperlipidemias/tratamiento farmacológico , Metabolismo de los Lípidos , Masculino , Tamaño de los Órganos , Conejos , Esterol O-Aciltransferasa/metabolismoRESUMEN
We reported that immunoelectron microscopy was an excellent tool for determining the subcellular localization of thiolase isozymes, acetoacetyl-CoA thiolase (T-I) and 3-ketoacyl-CoA thiolase (T-III) in n-alkane-grown Candida tropicalis cells (KAMASAWA, N. et al., (1992). Cell Struct. Funct., 17: 203-207). Current investigation on the visualization of other peroxisomal enzymes, acyl-CoA oxidase (ACO), catalase (KAT), carnitine acetyltransferase (CAT), isocitrate lyase (ICL) and malate synthase (MS), showed that ACO localized in peroxisomes, KAT in peroxisomes and cytoplasm, and CAT in peroxisomes, mitochondria and cytoplasm. Most of ICL and MS were found in peroxisomes. These results agreed with previous biochemical studies and supported the presumed roles of these enzymes. The same technique was applied to study the process of synthesis and localization of these enzymes early in the cultivation period in n-alkane medium when peroxisomes began to proliferate. ACO and T-III were rapidly induced after transfer of cells from glucose- to n-alkane-media. There was a drastic change of their location from cytoplasm to peroxisomes between 1 h and 2 h after the transfer, while T-I, KAT and CAT were moderately induced in cytoplasm and their location was gradually changed to each organelle. ICL and MS, the key enzymes in the glyoxylate cycle, were already localized in peroxisomes in the glucose-grown cells and respective inducible enzymes also were gradually localized there. This visual analysis is useful for the vivid elucidation of the process of peroxisome proliferation and enzyme transport within a cell.
Asunto(s)
Candida/enzimología , Candida/ultraestructura , Microcuerpos/enzimología , Alcanos/metabolismo , Candida/crecimiento & desarrollo , División Celular/fisiología , Inducción Enzimática/efectos de los fármacos , Proteínas Fúngicas/metabolismo , Microscopía InmunoelectrónicaRESUMEN
The in vitro potencies of a novel inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), E5324 (n-butyl-N'-[2-[3-(5-ethyl-4-phenyl-1H-imidazol-1-yl)propoxy]-6- methylphenyl]urea), were studied. E5324 was found to be a potent ACAT inhibitor in microsomes from a various tissues and in cultured cell homogenate, with IC50 values in the range of 0.044 to 0.19 microM. The kinetic study on E5324 showed that the inhibition of rat intestine ACAT was competitive with respect to oleoyl CoA. E5324 inhibited [3H]olate incorporation into cholesteryl [3H]oleate in phorbol ester-treated THP-1 cell lines (IC50 = 0.44 microM). The rate of [3H]oleate incorporation into phospholipids and triglycerides was not affected by E5324. In an experiment with [3H]cholesterol as the substrate for ACAT, E5324 also inhibited [3H]cholesteryl ester synthesis (IC50 = 0.41 microM). Furthermore, E5324 prevented accumulation of both esterified and total cholesterol in acetyl low density lipoprotein-loaded THP-1 cells. These results indicate that E5324 is a potent and selective ACAT inhibitor and prevents cholesteryl ester accumulation in macrophages.
Asunto(s)
Ésteres del Colesterol/metabolismo , Inhibidores Enzimáticos/farmacología , Macrófagos/metabolismo , Compuestos de Fenilurea/farmacología , Esterol O-Aciltransferasa/antagonistas & inhibidores , Animales , Colesterol/metabolismo , Ésteres del Colesterol/biosíntesis , Humanos , Técnicas In Vitro , Lipoproteínas/sangre , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Masculino , Ácidos Oléicos/metabolismo , Conejos , Ratas , Ratas Sprague-Dawley , Triglicéridos/metabolismo , Células Tumorales CultivadasRESUMEN
E5324, n-butyl-N'-[2-[3-(5-ethyl-4-phenyl-1H-imidazol-1-yl)propoxy]-6- methylphenyl]urea, a novel and orally absorbable acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor, was evaluated for its antiatherosclerotic and antihyperlipidemic effects in cholesterol-fed hypercholesterolemic rabbits. When administered concurrently with a high-cholesterol (0.5% cholesterol) diet for 12 weeks, E5324 (0.0025%, 0.005% and 0.01% in diet) lowered plasma total cholesterol levels dose-dependently (by about 55%-87% at the end of the experiment compared with the control) and also reduced atherosclerotic plaque formation (about 90% reduction at the highest dose; P < 0.01). In pre-established hypercholesterolemic rabbits, which had been pre-fed a high-cholesterol diet for 8 weeks, E5324 administered in the same diet at a dose of 0.005%, 0.01% or 0.02% for 4 weeks significantly reduced plasma cholesterol levels dose-dependently. Cholesterol content and ACAT activity in the aortic arch were also decreased (by about 72% and 58% at the highest dose, respectively) compared with the control. Another ACAT inhibitor, CI-976, had a similar action, but cholestyramine and probucol (2% and 1% in diet, respectively) lacked anti-atherosclerotic activity in this model. Furthermore, when pre-established hypercholesterolemic rabbits were fed normal rabbit chow diet with or without 0.02% E5324 for 4 weeks, changes in plasma cholesterol levels were similar in both E5324-treated and control groups. On the other hand, E5324 significantly reduced cholesterol content and ACAT activity in the aortic arch (by about 52% and 50%, respectively) compared with the control group. These results indicate that E5324 not only has hypocholesterolemic activity, but also may have a direct effect on the arterial wall in experimental atherosclerosis.
Asunto(s)
Arteriosclerosis/tratamiento farmacológico , Compuestos de Fenilurea/uso terapéutico , Anilidas/uso terapéutico , Animales , Aorta Torácica/metabolismo , Aorta Torácica/patología , Arteriosclerosis/metabolismo , Arteriosclerosis/patología , Resina de Colestiramina/uso terapéutico , Relación Dosis-Respuesta a Droga , Metabolismo de los Lípidos , Hígado/metabolismo , Hígado/patología , Masculino , Probucol/uso terapéutico , Conejos , Esterol O-Aciltransferasa/antagonistas & inhibidores , Esterol O-Aciltransferasa/metabolismo , Túnica Íntima/patología , Túnica Media/patologíaRESUMEN
We have discovered N-butyl-N'-[2-(dimethylamino)-6-[3-(4-phenyl-1H- imidazol-1-yl)propoxy]phenyl]urea (4), a novel, potent, and systemically bioavailable inhibitor of ACAT (acylCoA:cholesterol O-acyltransferase). The structure-activity relationships (SARs) of this lead compound 4 were investigated by systematic modification of four regions in the molecule. The compounds prepared in this study were tested for in vitro inhibitory activity toward both aortic and intestinal ACATs, and selected compounds were further tested for in vivo hypocholesterolemic activity. The studies not only resulted in the discovery of N-[2-(dimethylamino)-6-[3-(5-methyl-4-phenyl-1H-imidazol-1-yl) propoxy]phenyl]-N'-pentylurea (24), with potent activity and moderate plasma level after oral administration, but also revealed the SAR in each modified region. Four compounds (4, 13, 14, 24) were further selected for testing of in vivo antiatherosclerotic activity; 4, 13, and 24 reduced atherosclerotic plaque development to 38-45% of the control value in terms of area, while 14 did not have a significant antiatherosclerotic effect.
Asunto(s)
Anticolesterolemiantes/síntesis química , Arteriosclerosis/tratamiento farmacológico , Compuestos de Fenilurea/síntesis química , Esterol O-Aciltransferasa/antagonistas & inhibidores , Animales , Anticolesterolemiantes/farmacología , Aorta/enzimología , Técnicas In Vitro , Intestinos/enzimología , Masculino , Compuestos de Fenilurea/farmacología , Conejos , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
In our continuing search to find systemically bioavailable ACAT (acyl-CoA:cholesterol O-acyltransferase) inhibitors with more potent antiatherosclerotic effect than N-[2-(dimethylamino)-6-[3-(5-methyl-4-phenyl-1H-imidazol-1-yl)propoxy] phenyl]-N'-pentylurea (3), a series of phenylureas linked to 4-phenylimidazole were synthesized and evaluated for in vitro inhibitory activity toward both aortic and intestinal ACATs, and for in vivo hypocholesterolemic activity. The structure-activity relationships (SARs) were studied by strategic modification of five regions in the molecule of 3, i.e., by introducing functional groups or exchanging carbon atoms for heteroatoms. The SAR studies allowed us to select optimum substituents in the five regions, as follows. (1) Dimethylamino was convertible into nitro, methyl, ethyl, propyl, isopropyl, and chloro. On the basis of preliminary pharmacokinetic studies, the methyl group in the ortho-position of the phenylurea was selected. (2) Butyl, pentyl, isopentyl, and neopentyl were better substituents in the urea moiety. (3) Propoxy was the optimal moiety in the bridging portion. (4) Proton, methyl, ethyl, isopropyl, hydroxymethyl, and chloro were better substituents at the 5-position of the imidazole moiety. (5) An unsubstituted phenyl ring was selected as the phenyl group of phenylimidazole. The subsequent comparison studies of compounds containing various combinations of the optimum substituents in each region resulted in the selection of two compounds (67, 68) for further pharmacological and toxicological testing. These compounds were orally bioavailable, and possessed potent in vitro aortic ACAT inhibitory activity (IC50 = 0.16 and 0.012 microM, respectively) and in vivo cholesterol lowering effect (46% and 52% at 1 mg/kg po, respectively). In particular, 68 was 10-fold more potent in the in vitro aortic ACAT assay and 5-fold more potent with respect to hypocholesterolemic activity in vivo than 3.
Asunto(s)
Anticolesterolemiantes/síntesis química , Arteriosclerosis/tratamiento farmacológico , Imidazoles/síntesis química , Compuestos de Fenilurea/síntesis química , Esterol O-Aciltransferasa/antagonistas & inhibidores , Animales , Anticolesterolemiantes/farmacología , Aorta/enzimología , Imidazoles/farmacología , Técnicas In Vitro , Intestinos/enzimología , Masculino , Compuestos de Fenilurea/farmacología , Conejos , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
A middle-aged women with hypothyroidism, idiopathic portal hypertension and nephrotic syndrome is presented. This unusual clinical appearance could not be explained as SLE by serological examinations. Pathohistological examinations showed "Banti's liver", Hashimoto's thyroiditis and diffuse proliferative glomerulonephritis with severe tubulo-interstitial nephritis. Immunohistochemical studies revealed IgA deposits in glomeruli. Electron microscopic study disclosed peculiar lucent areas of rarefaction with osmiophilic particles in tubular basement membranes. This tubulointerstitial nephritis was considered to be related to the immunological mechanism involving thyroid gland, liver and kidney disorders. This case thus had a clinically rare combination of these three.
Asunto(s)
Glomerulonefritis/complicaciones , Hipertensión Portal/complicaciones , Nefritis Intersticial/complicaciones , Tiroiditis Autoinmune/complicaciones , Femenino , Glomerulonefritis/inmunología , Glomerulonefritis/patología , Humanos , Hipertensión Portal/patología , Inmunoglobulina A/metabolismo , Glomérulos Renales/inmunología , Microscopía Electrónica , Persona de Mediana Edad , Nefritis Intersticial/patologíaRESUMEN
The development of atheromatous lesions in the aortic arch of 0.5% cholesterol-fed rabbits was biochemically and morphologically examined. The animals were killed at week twelve (Cont-12W) or sixteen (Cont-16W). Both the micrographic and biochemical studies showed that the main atheromatous lesions in the Cont-12W group were fatty streaks, whereas those in the Cont-16W group were fibrous plaques. In these models, oral ingestion of 0.2% and 0.4% E5050, which has an antiproliferative effect on smooth muscle cells, had no effect on the surface involvement or the lipid content of the aortic arch at the sixteenth week, but reduced the degree of intimal thickening and the DNA content in the aortic arch in a dose-dependent manner. These results strongly suggest that E5050 suppresses the intimal thickening through its inhibitory effect on the proliferation of smooth muscle cells.
Asunto(s)
Aorta/efectos de los fármacos , Arteriosclerosis/tratamiento farmacológico , Dieta Aterogénica , Etanolaminas/farmacología , Animales , Aorta/patología , Colesterol/administración & dosificación , Colesterol/sangre , ADN/análisis , Etanolaminas/uso terapéutico , Masculino , ConejosRESUMEN
A high-performance liquid chromatographic method has been developed for the measurement of cholesterol 7 alpha-hydroxylase activity in liver microsomes. 7 alpha-Hydroxycholesterol generated from endogenous cholesterol was derivatized with anthroyl 1-carbonitrile, chromatographed on a reverse-phase column, and detected fluorometrically. The detection limit of 7 alpha-hydroxycholesterol was 1 ng/tube. The cholesterol 7 alpha-hydroxylase activity in rat liver microsomes was assayed by this method, and the effects of some detergents and of the addition of exogenous cholesterol together with detergents on the enzyme activity were investigated. The endogenous 7 alpha- and 7 beta-hydroxycholesterol could be also measured by this method.
Asunto(s)
Colesterol 7-alfa-Hidroxilasa/análisis , Cromatografía Líquida de Alta Presión/métodos , Esteroide Hidroxilasas/análisis , Acetona , Animales , Colesterol , Masculino , Microsomas Hepáticos/enzimología , Polisorbatos , Ratas , Ratas EndogámicasRESUMEN
Three different reactions are known to occur in a combined system of skeletal actin, gizzard myosin, and gizzard native tropomyosin. They were studied as functions of ATP concentration. (a) At around 1 microM ATP in the presence of an ATP-regenerating system, two of the three reactions, superprecipitation and ATPase reaction, occurred independently of calcium and were not accompanied by the third reaction, phosphorylation of myosin light chains. (b) Relatively high concentrations of ATP were required for calcium-dependent phosphorylation and for calcium-activated ATPase reaction. It is suggested that the apparent Km value for myosin light-chain kinase and that for acto-phosphorylated myosin-ATPase are approximately 10(-4.0) M and 10(-5.5) M, respectively. (c) The calcium-dependent phosphorylation and the calcium- activated ATPase reaction were closely coupled, but they were only indirectly coupled with superprecipitation. (d) In some of the responses to change in ATP concentration, (a)-(c), skeletal acto-gizzard myosin was similar to skeletal acto-skeletal myosin. It was also similar in that sulfhydryl groups of myosin are involved in the calcium regulation of actomyosin-ATPase and its superprecipitation in both cases.