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1.
Bacopa monniera Wettst. (BM, syn. Herpestis monniera L; Scrophulariaceae), is an Ayurvedic drug used as a rasayana. Its fresh juice was earlier reported to have significant antiulcerogenic activity. In continuation, methanolic extract of BM (BME) standardized to bacoside-A content (percentage-38.0 ± 0.9), when given in the dose of 10–50 mg/kg, twice daily for 5 days, showed dose-dependent anti-ulcerogenic on various gastric ulcer models induced by ethanol, aspirin, 2 h cold restraint stress and 4 h pylorus ligation. BME in the dose of 20 mg/kg, given for 10 days, twice daily showed healing effects against 50% acetic acid-induced gastric ulcers. Further work was done to investigate the possible mechanisms of its action by studying its effect on various mucosal offensive acid-pepsin secretion and defensive factors like mucin secretion, mucosal cell shedding, cell proliferation and antioxidant activity in rats. BME 20 mg/kg showed no effect on acid-pepsin secretion, increased mucin secretion, while it decreased cell shedding with no effect on cell proliferation. BME showed significant antioxidant effect per se and in stressed animals. Thus, the gastric prophylactic and curative effects of BME may be due to its predominant effect on mucosal defensive factors. 相似文献
2.
Biochemical, biological, and immunological properties of chemically deglycosylated human choriogonadotropin 总被引:5,自引:0,他引:5
A chemical method of deglycosylation of human choriogonadotropin (hCG) was used to assess the role of carbohydrate moiety in the maintenance of quaternary structure and functional parameters such as receptor binding, immunological activity, and in vitro biological response. Treatment of purified hCG with anhydrous HF at 0 degrees C for 60 min was effective in removing more than 75% of the carbohydrate moiety. This extent of deglycosylation altered its chromatographic characteristics as revealed by retarded behavior on Sephadex G-100 and failure to be retained on concanavalin A-Sepharose. The electrophoretic heterogeneity present in native hCG was markedly reduced by deglycosylation. The deglycosylated hCG was stable in the lyophilized form and retained its quaternary structure as revealed by the fluorescence probe 8-anilino 1-naphthalene sulfonic acid, receptor binding, and immunological activities. Unlike receptor binding and immunological activities, which were fully retained, the ability of the hormone to stimulate cyclic AMP accumulation in vitro in rat interstitial cells was completely abolished. 相似文献
3.
Bovine seminal plasma contains three similar acidic proteins, which we have previously designated as BSP-A1, BSP-A2, and BSP-A3. These proteins contain two homologous domains that are similar to type II structures present in the gelatin-binding domain of fibronectin. The present data have revealed that these proteins, like fibronectin, also form complexes with gelatin, a denatured collagen. Based on this property, a single step affinity purification method has been developed. In addition to these three proteins BSP-A1, -A2 and -A3, another protein with an apparent molecular weight of 30,000 dalton (named BSP-30-kDa) also bound to the gelatin-agarose column. Elution of these proteins from affinity columns using a linear gradient of either urea or arginine gave essentially the same pattern with a high yield of 90–95%. The purified proteins were homogeneous by SDS-polyacrylamide gel electrophoresis, amino acid composition and HPLC. Chromatography of bull seminal vesicular fluid also exhibited an elution pattern similar to that obtained for bull seminal plasma. The availability of these purified proteins should aid in understanding the physiology of these gelatin-binding proteins. 相似文献
4.
Complete amino acid sequence of BSP-A3 from bovine seminal plasma. Homology to PDC-109 and to the collagen-binding domain of fibronectin. 总被引:3,自引:0,他引:3 下载免费PDF全文
N G Seidah P Manjunath J Rochemont M R Sairam M Chrétien 《The Biochemical journal》1987,243(1):195-203
Bovine seminal plasma was shown to contain three similar proteins, called BSP-A1, BSP-A2 and BSP-A3. Both BSP-A1 and BSP-A2 were shown to be molecular variants of a recently characterized peptide called PDC-109. They seem to differ only in their degree of glycosylation and otherwise seem to possess an identical amino acid composition. The work in the present paper deals with the complete characterization of the third member of this series, namely BSP-A3. The complete amino acid sequence revealed that it is composed of 115 amino acids and predicts a Mr of 13,403. An analysis of the primary structure of BSP-A3 revealed a high degree of internal homology, with two homologous domains composed of 39 (residues 28-66) and 43 (residues 73-115) amino acids. An exhaustive computer-bank search for the similarity of this sequence to any known protein, or segment thereof, revealed two significant homologies. The first is between PDC-109 and BSP-A3, which is so high that we can confidently predict that both proteins evolved from a single ancestral gene. The collagen-binding domain of bovine fibronectin (type II sequence) was also found to be highly homologous to both BSP-A3 and PDC-109. 相似文献
5.
The binding of 125I-labeled ovine follitropin (oFSH) and 125I-labeled deglycosylated ovine follitropin (DG-oFSH) to porcine granulosa cell membranes was studied at equilibrium and nonequilibrium binding conditions and statistically analyzed. Saturation and competition binding experiments revealed homogeneity in the population of binding sites labeled with 125I-oFSH, having a pK estimation of approximately equal to 10. 125I-DG-oFSH similarly interacts with a single uniform class of receptors of equal affinity (pK approximately equal to 10) and binding capacity as oFSH. In contrast, displacement experiments using 125I-DG-oFSH as tracer and unlabeled oFSH as competing ligand demonstrate slope factors less than unity, suggesting apparent heterogeneity of sites not observed with 125I-DG-oFSH vs. DG-oFSH competition experiments. Under these conditions, it appears that FSH binds to two sites in near equal proportion but of unequal affinities. The total specific binding capacities of these sites equal those observed in 125I-DG-oFSH/unlabeled DG-oFSH competition experiments. Analysis of oFSH association kinetics at 37 degrees C by curve-fitting methods is best explained by a biexponential rate equation describing a fast and a slow association component that are equally distributed. DG-oFSH demonstrates a disproportionately greater amount of fast vs. slow binding component. The binding half-times for each component of oFSH and DG-oFSH are similar, i.e., minutes for the fast and hours for the slow t 1/2 times. At 37, 25, and 4 degrees C, DG-oFSH exhibits greater velocity of binding to the receptor than oFSH.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
The relative ability of ovine follicle stimulating hormone and itsβ-subunit, two potential candidates for male contraceptive vaccine, to generate antibodies in monkeys capable of bioneutralizing
follicle stimulating hormone was assessed usingin vitro model systems. Antiserum against native ovine follicle stimulating hormone was found to be highly specific to the intact
form with no cross-reactivity with either of the two subunits while the antiserum againstβ-subunit of follicle stimulating hormone could bind to theβ-subunit in its free form as well as when it is combined withα-subunit to form the intact hormone. Both antisera could block the binding of the hormone to the receptor if the hormone was
preincubated with the antibody. However, the follicle stimulating hormoneβ-antisera could only inhibit the binding of the hormone partially (33% inhibition) if the antibody and receptor were mixed
prior to the addition of the hormone, while antisera to the native follicle stimulating hormone could block the binding completely
(100% inhibition) in the same experiment. Similarly antisera to the native follicle stimulating hormone was significantly
effective in blocking (100%) response to follicle stimulating hormone but not theβ-subunit antisera (0%) as checked using anin vitro granulosa cell system. Thus the probability of obtaining antibodies of greater bioneutralization potential is much higher
if intact hormone is used as an antigen rather than itsβ-subunit as a vaccine.
Majority of the work reported here was carried out during the tenure of Visiting Scientist fellowship awarded by the MRC Canada
to the first author. 相似文献
7.
Chemical deglycosylation of ovine pituitary lutropin with anhydrous HF has been investigated. Treatment of the hormone for 75 min at 0 °C removed nearly two-thirds of the carbohydrate moiety. Deglycosylation altered the gel filtration and electrophoretic behavior of the hormone. Carbohydrate removal also resulted in dissociation into subunits to the extent of about 20%. In a rat ovarian radioreceptor assay, the deglycosylated hormone derivatives had approximately 35–40% of the binding activity of the native hormone. Immunological activity was fully retained as seen by the gel diffusion method and an α-subunit conformation oriented radioimmunoassay. In collagenase dispersed rat testicular interstitial cells, the derivatives had poor steroidogenic activity (less than 3%) and failed to elicit maximal testosterone production. The deglycosylated derivatives effectively antagonized the steroidogenic activity of the native hormone in rat testicular interstitial cells. 相似文献
8.
Samaiya Puneet K. Krishnamurthy Sairam Kumar Ashok 《Molecular and cellular biochemistry》2021,476(12):4421-4434
Molecular and Cellular Biochemistry - Perinatal asphyxia (PA)-induced brain injury may present as hypoxic-ischemic encephalopathy in the neonatal period, and long-term sequelae such as spastic... 相似文献
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