scholarly journals Enhancement of aromatase activity by D-aspartic acid in the ovary of the lizard Podarcis s. sicula

Reproduction ◽  
2001 ◽  
pp. 803-808 ◽  
Author(s):  
L Assisi ◽  
V Botte ◽  
A D'Aniello ◽  
MM Di Fiore
Keyword(s):  
Amino Acids ◽  
Aspartic Acid ◽  
Reproductive Cycle ◽  
Catalytic Properties ◽  
Ovarian Tissue ◽  
Experimental Treatment ◽  
Tissue Homogenate ◽  
Aromatase Activity

The present study investigated the role of D-aspartic acid (D-Asp) in ovarian steroidogenesis and its effect on aromatase activity in the lizard, Podarcis s. sicula. It was determined that D-Asp concentrations vary significantly during phases of the reproductive cycle: they vary inversely with testosterone concentrations and directly with oestradiol concentrations in the ovary and plasma. Experimental treatment showed that administration of D-Asp induces a decrease in testosterone and an increase in oestradiol, and that treatment with other amino acids (L-Asp, D-Glu and D-Ala) instead of D-Asp has no effects. Experiments in vitro confirmed these results. Furthermore, these experiments showed an increase in aromatase activity, as the addition of D-Asp either to fresh ovarian tissue homogenate or to acetonic powder of ovarian follicles induced a significant increase in the conversion of testosterone to oestradiol. Aromatase activity is four times greater in the presence of D-Asp than in its absence. However, almost equivalent values of the two K(m) values (both approximately 25 nmol l(-1)) indicate that aromatase has the same catalytic properties in both cases.

scholarly journals Aromatase P450 activity in the natural menstrual cycle and during controlled ovarian stimulation

2017 ◽  
Vol 66 (5) ◽  
pp. 46-55 ◽  
Author(s):  
Pavel P. Yakovlev
Keyword(s):  
Reproductive System ◽  
Oocyte Quality ◽  
Aromatase Activity ◽  
Female Reproductive System ◽  
Vitro Fertilization ◽  
P450 Enzyme ◽  
Follicular Response ◽  
P450 Activity

The Aim of the study was to assess modern considerations about the role of aromatase P450 enzyme in female reproductive system and the effect of its activity on the protocols of in vitro fertilization (IVF). Materials: foreign and Russian literature data from 1978 to 2016. Methods:review and synthesis of publications has been performed. Conclusions: Ovarian aromatase is the key steroidogenesis enzyme of the female reproductive system. Its activity depends on many factors, both of intraovarian and extragonadal origin. The ovarian follicular response and oocyte quality in IVF may depend on aromatase activity.

scholarly journals Some biochemical effects of triamcinolone acetonide on rat liver and muscle

1970 ◽  
Vol 116 (3) ◽  
pp. 349-355 ◽  
Author(s):  
R. F. Peters ◽  
M. C. Richardson ◽  
Margaret Small ◽  
A. M. White
Keyword(s):  
Amino Acids ◽  
Triamcinolone Acetonide ◽  
Time Course ◽  
Muscle Protein ◽  
Specific Radioactivity ◽  
Synthetic Activity ◽  
Tissue Homogenate ◽  
Glycogen Concentration

1. The powerful anti-inflammatory glucocorticoid triamcinolone acetonide, administered to rats at 20 and 2.5mg/kg, leads to a decrease in the incorporation in vivo of [3H]uridine and [32P]orthophosphate into hind-limb skeletal muscle. 2. At the higher dose, this decrease in the rate of incorporation of precursors into RNA precedes a decrease in the incorporating ability of muscle ribosomes, which commences about 4–5h after drug administration, but is unaccompanied by any changes in the concentration of tissue ATP or free amino acids. 3. The ribosomal dysfunction extends to polyribosomes, which can only be successfully isolated from the muscle of triamcinolone-treated animals after the addition of α-amylase to the tissue homogenate to remove glycogen. 4. The specific radioactivity of muscle protein labelled in vivo with 14C-labelled amino acids does not decrease progressively after triamcinolone administration. After 2h there is an apparent stimulation of incorporation which leads to an overall discrepancy between measurements of protein-synthetic activity made in vivo and in vitro. 5. There is a significant increase in muscle-glycogen concentration between 8 and 12h after the administration of triamcinolone acetonide (20mg/kg), although a significant decrease occurs after 4h. The fall in glycogen concentration may be due to a decrease in the rate of synthesis of protein essential for glucose uptake into the tissues. 6. As judged by (a) incorporation of 14C-labelled amino acids into protein, (b) [3H]uridine and [32P]-orthophosphate incorporation into RNA, (c) the rate of induction of tryptophan pyrrolase and (d) changes in the pool sizes of taurine and tryptophan, the responses in liver followed the same time-course as those in muscle after administration of the drug.

THE ROLE OF KETO ACIDS IN PHOTOSYNTHETIC CARBON DIOXIDE ASSIMILATION

1956 ◽  
Vol 34 (1) ◽  
pp. 511-519 ◽  
Author(s):  
G. H. N. Towers ◽  
D. C. Mortimer
Keyword(s):  
Carbon Dioxide ◽  
Amino Acids ◽  
Sugar Beet ◽  
Aspartic Acid ◽  
Pyruvic Acid ◽  
Carbon Dioxide Assimilation ◽  
Free Air ◽  
Keto Acids ◽  
Photosynthetic Carbon

Of the keto acids identified in leaves of sugar beet and other plants exposed to C14O2, pyruvic acid was found to be the only one labelled in light periods up to 45 sec. α-Ketoglutaric and glyoxylic acids became radioactive after about 45 sec. Radioactive hydroxypyruvate was not identified under these conditions and labelled oxaloacetate was detected only in trace amounts after 60 sec. in Scenedesmus. In contrast glycine and serine were labelled after 10 sec. under comparable conditions and aspartic acid was appreciably labelled after 30 sec. The effect on the radioactivity of the keto acids of an additional period intracer-free air, with and without light, as well as the dark incorporation of C14O2 was studied. These results are discussed in relation to the role of the ketoacids in photosynthesis. It is concluded that the synthesis of amino acids such as glycine, serine, and aspartic acid may be effected by mechanisms other than transamination in green leaves in the light.

scholarly journals Identification of a talin binding site in the cytoskeletal protein vinculin.

1989 ◽  
Vol 109 (6) ◽  
pp. 2917-2927 ◽  
Author(s):  
P Jones ◽  
P Jackson ◽  
G J Price ◽  
B Patel ◽  
V Ohanion ◽  
...  
Keyword(s):  
Amino Acids ◽  
In Vitro Transcription ◽  
Binding Activity ◽  
Cytoskeletal Protein ◽  
Translation System ◽  
Cos Cells ◽  
Cell Matrix ◽  
Do So

Binding of the cytoskeletal protein vinculin to talin is one of a number of interactions involved in linking F-actin to cell-matrix junctions. To identify the talin binding domain in vinculin, we expressed the NH2-terminal region of the molecule encoded by two closely similar, but distinct vinculin cDNAs, using an in vitro transcription translation system. The 5' Eco RI-Bam HI fragment of a partial 2.89-kb vinculin cDNA encodes a 45-kD polypeptide containing the first 398 amino acids of the molecule. The equivalent restriction enzyme fragment of a second vinculin cDNA (cVin5) lacks nucleotides 746-867, and encodes a 41-kD polypeptide missing amino acids 167-207. The radiolabeled 45-kD vinculin polypeptide bound to microtiter wells coated with talin, but not BSA, and binding was inhibited by unlabeled vinculin. In contrast, the 41-kD vinculin polypeptide was devoid of talin binding activity. The role of residues 167-207 in talin binding was further analyzed by making a series of deletions spanning this region, each deletion of seven amino acids contiguous with the next. Loss of residues 167-173, 174-180, 181-187, 188-194, or 195-201 resulted in a marked reduction in talin binding activity, although loss of residues 202-208 had much less effect. When the 45-kD vinculin polypeptide was expressed in Cos cells, it localized to cell matrix junctions, whereas the 41-kD polypeptide, lacking residues 167-207, was unable to do so. Interestingly, some deletion mutants with reduced ability to bind talin in vitro, were still able to localize to cell matrix junctions.

Amino Acid Transporter X Is Required for Hematopoietic Stem Cell Maintenance through Regulating Specific Amino Acids Level

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1166-1166 ◽  
Author(s):  
Zhenrui Li ◽  
Keiyo Takubo ◽  
Pengxu Qian ◽  
Toshio Suda ◽  
Linheng Li
Keyword(s):  
Amino Acids ◽  
Stem Cell ◽  
Amino Acid ◽  
Acid Metabolism ◽  
Hematopoietic Stem ◽  
Cell Pool ◽  
Stem Cell Pool

Abstract Hematopoietic stem cells (HSCs) maintenance is required to preserve stem cell pool and compensate the dynamic loss of blood cells. Previous studies of HSCs maintenance mainly focus on the quiescent versus active state of HSCs and accumulated evidence indicates that metabolism plays a critical role in coordinating divergent stem cell states. While recent reports largely emphasized the role of catabolic glycolysis on long-term (LT) HSC maintenance, we found that free amino acids are enriched in primitive stem cell by ~1.5 fold. Given that amino acid metabolism in HSCs is largely unknown, we first cultured bone marrow (BM) cells with individual amino acid deprived medium to study the function of individual amino acids on HSCs in vitro. Surprisingly, we found that specific amino acids, including valine, methionine and threonine (VMT), are essential for maintaining primitive HSCs, as removing them (VMT) individually from media dramatically reduced primitive HSC number by over 95%. Thus, we hypothesize that specific amino acids are critical for preserving the stem cell pool and maintaining their function. To test it, we transplanted equal number of cells cultured with complete or individual VMT deprived media into lethally irradiated recipient mice and found VMT deprivation in vitro impaired stem cell repopulation ability. We also identified the amino acid transporter X (AATX) that is specifically expressed in HSCs and maintain VMT levels within the cell. Furthermore, inhibition of AATX reduced LT-HSC (LSK CD34- Flk2-) number in vivo. BM transplantation indicated that AATX inhibition impaired stem cell long-term reconstitution ability by over 2 fold. Our studies uncovered a role of amino acid metabolism in HSC maintenance and discovered the underlying molecular mechanism related to the amino acid transport. This finding may impact clinical treatment of blood disorders including leukemia. Disclosures No relevant conflicts of interest to declare.

Influence of hormone environment and donor age on cryopreserved common wombat (Vombatus ursinus) ovarian tissue xenografted into nude mice

2004 ◽  
Vol 16 (7) ◽  
pp. 699 ◽  
Author(s):  
M. Cleary ◽  
J. M. Shaw ◽  
G. Jenkin ◽  
A. O. Trounson
Keyword(s):  
Nude Mice ◽  
Ovarian Tissue ◽  
Follicle Development ◽  
Kidney Capsule ◽  
Oocyte Collection ◽  
Common Wombat ◽  
Tissue Grafts ◽  
Gonadal Status

Developmentally competent oocytes can be collected from xenografted ovarian tissues; however, optimal xenograft conditions need to be established for this technique to be of use in assisted reproduction. In the present study, common wombat ovarian tissue was xenografted under the kidney capsule of nude mice to clarify the role of recipient gonadal status and donor tissue age on graft establishment, follicle development and oocyte recovery. Eighty-nine per cent of all grafts were recovered; of these, 78% contained growing follicles. In female graft recipients, follicle development to the antral stage occurred earlier in ovariectomised recipients compared with intact graft recipients. Similarly, follicle development occurred earlier in recipients of pouch young ovarian tissue grafts when compared with subadult xenografts. Follicle development proceeded to the antral stage in subadult grafts placed under the kidney capsule of male recipient mice, albeit at a slower rate than subadult grafts placed in female recipients. Oocytes were collected from grafts placed in female and male recipients, but no mature oocytes were observed at the time of collection, nor could these oocytes be matured in vitro. The present study demonstrated that common wombat pouch young tissue xenografted to female recipient mice, and subadult ovarian tissue xenografted to male recipient mice, can develop to the antral stage and can therefore facilitate oocyte collection. However, mature oocytes were not obtained using the current protocol.

Essential role of follicle stimulating hormone in the maintenance of caprine preantral follicle viability in vitro

Zygote ◽  
2007 ◽  
Vol 15 (2) ◽  
pp. 173-182 ◽  
Author(s):  
M.H.T. Matos ◽  
I.B. Lima-Verde ◽  
M.C.A. Luque ◽  
J.E. Maia Jr ◽  
J.R.V. Silva ◽  
...  
Keyword(s):  
Ovarian Tissue ◽  
Follicle Stimulating Hormone ◽  
Control Medium ◽  
Primordial Follicles ◽  
Ultrastructural Studies ◽  
Follicle Diameter ◽  
Transmission Electron ◽  
Stimulating Hormone

SummaryThe aims of the present study were to investigate the effects of follicle-stimulating hormone (FSH) on survival, activation and growth of caprine primordial follicles using histological and ultrastructural studies. Pieces of caprine ovarian cortex were cultured for 1 or 7 days in minimum essential medium (MEM – control medium) supplemented with different concentrations of FSH (0, 10, 50 or 100 ng/ml). Small fragments from non-cultured ovarian tissue and from those cultured for 1 or 7 days in a specific medium were processed for classical histology and transmission electron microscopy (TEM). Additionally, effects of FSH on oocyte and follicle diameter of cultured follicles were evaluated. The results showed that the lowest percentage of normal follicles was observed after 7 days of culture in control medium. After 1 day of culture, a higher percentage of growing follicles was observed in the medium supplemented with 50 ng/ml of FSH. In the presence of 10 and 50 ng/ml of FSH, an increase in diameter of both oocyte and follicle on day 7 of culture was observed. TEM showed ultrastructural integrity of follicles after 1 day of culture in MEM and after 7 days in MEM plus 50 ng/ml FSH, but did not confirm the integrity of those follicles cultured for 7 days in MEM. In conclusion, this study demonstrated that FSH at concentration of 50 ng/ml not only maintains the morphological integrity of 7 days cultured caprine preantral follicles, but also stimulate the activation of primordial follicles and the growth of activated follicles.

Exploring the role of ions and amino acids in directing the growth of minerals from solution

2008 ◽  
Vol 72 (1) ◽  
pp. 273-276 ◽  
Author(s):  
S. Piana ◽  
F. Jones ◽  
Z. Taylor ◽  
P. Raiteri ◽  
J. D. Gale
Keyword(s):  
Amino Acids ◽  
Computer Simulation ◽  
Free Energy ◽  
Aspartic Acid ◽  
Morphology Control ◽  
New Approach ◽  
Activation Free Energy

AbstractThe influence of both sulphate ions and aspartic acid on directing the growth of baryte has been explored using computer simulation. Both species are found to significantly reduce the activation free-energy to growth under appropriate conditions, with the influence of sulphate being surface specific. This offers the potential for a new approach to morphology control without inhibition that may have implications for biomineralization.

scholarly journals The Role of Amino Acids for the In Vitro Culture of Some Species of Forage Legumes I. Trifolium pratense L

2013 ◽  
Vol 70 (1) ◽  
pp. 87-92
Author(s):  
Gabriela Maria VICAȘ ◽  
Mircea SAVATTI
Keyword(s):  
Amino Acids ◽  
In Vitro Culture ◽  
Culture Medium ◽  
Trifolium Pratense ◽  
Basal Medium ◽  
Red Clover ◽  
Forage Legumes ◽  
Trifolium Pratense L

Establishing the effect of the amino acids as additional additives to the culture medium is and will be in the future one of our concerns of interest for the in vitro culture of some plants. The present study examines the effect of the glicocol added to the LS basal medium over the embryos of the Trifolium pratense L specie cultivated in vitro. There were followed: the percentage of plant regeneration of the red clover, its multiplication capacity and the formation of the root system, and also the evolution of the callus obtained on mediums with 2,4D, BA and amino acid.

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