The influence of oleic acid on cAMP accumulation of thyroid plasma membrane activated by thyrotropin

1988 ◽  
Vol 117 (1) ◽  
pp. 125-129
Author(s):  
Tien-Chun Chang ◽  
Tien-Shang Huang
Keyword(s):  
Plasma Membrane ◽  
Oleic Acid ◽  
Thyroid Hormone ◽  
Plasma Membranes ◽  
Albumin Concentration ◽  
Adenylate Cyclase System ◽  
Camp Accumulation ◽  
Hormone Binding ◽  
High Oleic ◽  
Oleic Acid Concentration

Abstract. Several thyroid hormone binding inhibitors have been described in nonthyroid illness. One of the major inhibitors, oleic acid, is present in excess amounts in sera of patients with nonthyroid illness. In this study, we demonstrated that oleic acid inhibited the cAMP accumulation of thyroid plasma membrane activated by thyrotropin at 50 μmol/l and higher concentrations. In the presence of albumin, oleic acid significantly inhibited the cAMP accumulation of plasma membrane activated by thyrotropin at 2.4 mmol/l (P < 0.01 when the albumin concentration was 40 g/l and pH was 7.4; P < 0.001 when the albumin concentration was 20 g/l and pH was 7.2). These findings suggest that in nonthyroid illness, especially at a low albumin concentration and low blood pH, a high oleic acid concentration may influence the thyroid function directly in addition to inhibiting the thyroid hormone binding to serum protein. Oleic acid also could inhibit 5′-guanylylimidodiphosphate- and forskolin-induced cAMP production in thyroid plasma membranes. Therefore, the inhibiting effect of oleic acid may be through the action of oleic acid on the catalytic unit of the hormone-sensitive adenylate cyclase system.

Thyroid Hormone Binding Inhibitor (THBI) Mainly Associated with Serum Oleic Acid Concentration

1985 ◽  
Vol 17 (08) ◽  
pp. 426-427 ◽  
Author(s):  
J. Herrmann ◽  
G. Alasso ◽  
M. Beyer ◽  
E. Heinen ◽  
J. Römisch ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Thyroid Hormone ◽  
Acid Concentration ◽  
Hormone Binding ◽  
Oleic Acid Concentration

Adenylate cyclase activity in Y1 mouse adrenocortical tumor cells: some properties of the enzyme associated with purified plasma membrane fractions

1983 ◽  
Vol 61 (7) ◽  
pp. 547-552 ◽  
Author(s):  
Bernard P. Schimmer
Keyword(s):  
Plasma Membrane ◽  
Adenylate Cyclase ◽  
Plasma Membranes ◽  
Tumor Cell Line ◽  
Cyclase Activity ◽  
Adenylate Cyclase Activity ◽  
Adenylate Cyclase System ◽  
Adrenocortical Tumor ◽  
Intact Cells ◽  
Order Of Magnitude

Fractions enriched in plasma membranes were prepared from the Y1 mouse adrenocortical tumor cell line and were characterized with respect to adenylate cyclase activity. Optimal requirements of the adenylate cyclase system for guanyl nucleotides, Mg2+, ATP, and corticotropin (ACTH) were determined. The sensitivity of the adenylate cyclase system to ACTH1–24 in plasma membrane fractions was comparable with that observed in isolated intact cells. Polycations such as poly-L-arginine and histone competitively inhibited the action of ACTH1–24, supporting the view that the affinity of ACTH for the adenylate cyclase system is determined by the basic core of amino acids at residues 15–18. ACTH1–24 was at least one order of magnitude more potent than ACTH1–39 in stimulating adenylate cyclase activity in plasma membrane fractions.

scholarly journals Recombinant Oleate Hydratase from Lactobacillus rhamnosus ATCC 53103: Enzyme Expression and Design of a Reliable Experimental Procedure for the Stereoselective Hydration of Oleic Acid

Catalysts ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1122
Author(s):  
Antonio Castagna ◽  
Davide De Simeis ◽  
Erica E. Ferrandi ◽  
Stefano Marzorati ◽  
Daniela Monti ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Substrate Inhibition ◽  
Lactobacillus Rhamnosus ◽  
Probiotic Strain ◽  
Hydration Reaction ◽  
E Coli ◽  
High Oleic ◽  
Oleic Acid Concentration ◽  
Microbial Strains ◽  
Oleate Hydratase

Different microbial strains are able to transform oleic acid (OA) into 10-hydroxystearic acid (10-HSA) by means of the catalytic activity of the enzymes oleate hydratase (EC 4.2.1.53). Lactobacillus rhamnosus ATCC 53103 performs this biotransformation with very high stereoselectivity, affording enantiopure (R)-10-HSA. In this work, we cloned, in Escherichia coli, the oleate hydratase present in the above-mentioned probiotic strain. Our study demonstrated that the obtained recombinant hydratase retains the catalytic properties of the Lactobacillus strain but that its activity was greatly affected by the expression procedure. According to our findings, we devised a reliable procedure for the hydration of oleic acid using a recombinant E. coli whole-cell catalyst. We established that the optimal reaction conditions were pH 6.6 at 28 °C in phosphate buffer, using glycerol and ethanol as co-solvents. According to our experimental protocol, the biocatalyst does not show significant substrate inhibition as the hydration reaction can be performed at high oleic acid concentration (up to 50 g/L).

Differences in Development of Oleic and Linoleic Acid in High- and Normal-Oleic Virginia and Runner-Type Peanuts

2016 ◽  
Vol 43 (1) ◽  
pp. 12-23 ◽  
Author(s):  
C.M. Klevorn ◽  
K.W. Hendrix ◽  
T.H. Sanders ◽  
L.L. Dean
Keyword(s):  
Oleic Acid ◽  
Fatty Acid ◽  
Linoleic Acid ◽  
Food Industry ◽  
Growing Season ◽  
Fatty Acid Profiles ◽  
Fresh Weight ◽  
High Oleic ◽  
Harvest Dates ◽  
Oleic Acid Concentration

ABSTRACT A consistent, pure supply of high-oleic (HO) peanuts is important to certain segments of the food industry as it allows for the production of confections and other products with improved shelf-life characteristics. Peanut shellers have struggled with food industry demands for lots which contain greater than 95% high-oleic peanuts. Normal-oleic (NO) and HO cultivars of virginia and runner market type peanuts were grown during the 2012 and 2013 growing season respectively to investigate differences in fatty acid development between HO and NO peanuts. Fatty acid profiles of individual seeds from individual plants taken across the growing season were determined in relation to seed fresh weight. Fatty acid profiles of HO virginia-type seeds from the early sampling date of 78 days after planting (DAP) revealed oleic acid to linoleic acid ratios (O/L) of only 4.0 in the seeds of the greatest fresh weight. As the oleic acid concentration in many of the HO virginia-type peanuts reached 60 to 80% and the linoleic acid concentrations ranged from less than 1.0 to 10 % by the middle sampling date (106 DAP), the O/L ratios of most HO seeds were well above the industry accepted cut-off ratio of 9.0. A similar change in the fatty acids was seen in the HO runner cultivar. Increases in oleic acid and decreases in linoleic acid contents occurred in conjunction with the increased seed fresh weights. The data indicate that HO seed attain high-oleic status as physiological development progresses as seen in the changing seed fresh weight. However at the final sampling dates which corresponded to the harvest dates, O/L ratios of less than 9.0 were still present for the HO cultivars of both market types despite the fresh weight of some seeds being of potential marketable size. It was concluded that some of the perceived contamination of HO seed lots with NO seed could be the result of normal peanut development, especially in the virginia-type cultivar with the larger sized seeds.

scholarly journals Measurements of Oleic Acid among Individual Kernels Harvested from Test Plots of Purified Runner and Spanish High Oleic Seed

2017 ◽  
Vol 44 (2) ◽  
pp. 134-142 ◽  
Author(s):  
J. P. Davis ◽  
J.M. Leek ◽  
D.S. Sweigart ◽  
P. Dang ◽  
C.L. Butts ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Acid Concentration ◽  
Kernel Size ◽  
Late Season ◽  
High Oleic ◽  
Chemistry Development ◽  
Oleic Acid Concentration ◽  
Soil Temperatures ◽  
Type Data ◽  
Kernel Level

ABSTRACT Normal oleic peanuts are often found within commercial lots of high oleic peanuts when sampling among individual kernels. Kernels not meeting high oleic threshold could be true contamination with normal oleic peanuts introduced via poor handling, or kernels not meeting threshold could be immature and not fully expressing the trait. Beyond unintentional mixing, factors contributing to variation in oleic acid concentration in peanut kernels include market type, environment, maturity and/or kernel size; however, the relative influence of these factors, and their interactions, is not quantitatively well understood on the single kernel level. To better understand these factors while simultaneously excluding variation from unintentional mixing, seed from a high oleic spanish cultivar and seed from a high oleic runner cultivar were carefully purified via NIR technology. The purified seed were planted in environmentally controlled test plots to analyze the progeny for oleic acid chemistry. Post flowering, plot sections were either chilled (3.8 -5.0 C below ambient), maintained at ambient or heated (3.8-5.0 C above ambient) in the pod zone to characterize soil temperature effects on oleic acid chemistry development. Fully randomized (4 reps) plots included the purified high oleic spanish and runner cultivars, three soil temperatures, seed maturity (profile board), commercial kernel size classifications, and a late season flower termination protocol. At harvest, the oleic acid concentration of approximately 24,000 individual kernels were measured via NIR technology. Market type, temperature, maturity and size had a significant effect on high oleic chemistry among kernels. Late season flower termination significantly, and positively, influenced high oleic chemistry of runner peanuts, minimized the number of immature kernels not meeting high oleic threshold and resulted in elevated and more consistent distributions in this key chemistry; distributions that were more similar to those of the more botanically determinate, but lower yielding, spanish market type. Data from this study improves our understanding of expected natural variation in high oleic chemistry and suggests late season flower termination of runner peanuts is a viable strategy to maximize high oleic chemistry on the single kernel level.

Membrane microdomains: lessons from microscopy

1995 ◽  
Vol 53 ◽  
pp. 776-777
Author(s):  
J.M. Robinson ◽  
J.M Oliver
Keyword(s):  
Spatial Distribution ◽  
Plasma Membrane ◽  
Epithelial Cells ◽  
Plasma Membranes ◽  
Cell Types ◽  
Imaging Modalities ◽  
Membrane Microdomains ◽  
Membrane Domains ◽  
Lateral Heterogeneity ◽  
Functional Importance

Specialized regions of plasma membranes displaying lateral heterogeneity are the focus of this Symposium. Specialized membrane domains are known for certain cell types such as differentiated epithelial cells where lateral heterogeneity in lipids and proteins exists between the apical and basolateral portions of the plasma membrane. Lateral heterogeneity and the presence of microdomains in membranes that are uniform in appearance have been more difficult to establish. Nonetheless a number of studies have provided evidence for membrane microdomains and indicated a functional importance for these structures.This symposium will focus on the use of various imaging modalities and related approaches to define membrane microdomains in a number of cell types. The importance of existing as well as emerging imaging technologies for use in the elucidation of membrane microdomains will be highlighted. The organization of membrane microdomains in terms of dimensions and spatial distribution is of considerable interest and will be addressed in this Symposium.

DIAGNOSIS TIROID

2016 ◽  
Vol 21 (3) ◽  
pp. 304
Author(s):  
Liong Boy Kurniawan ◽  
Mansyur Arif
Keyword(s):  
Thyroid Hormone ◽  
Laboratory Tests ◽  
Thyroid Disorder ◽  
Functional Tests ◽  
Hormone Binding ◽  
Functional Diagnosis ◽  
Underlying Condition ◽  
Unusual Combination ◽  
The Right ◽  
Underlying Diseases

Thyroid disease often causes unspecific or mild symptoms, so laboratory tests are needed to confirm the functional diagnosis of the thyroid disorder. The laboratory tests which are important to establish the diagnosis of thyroid disorder include: total and free thyroidhormones, its related (thyroid) hormone binding proteins and auto antibodies. The thyroid hormone tests are mostly measured with competitive or sandwich immunoassays and each method can be interfered by several factors. Some drugs may increase or decrease thethyroid functional tests and several factors such as: underlying diseases, age, pregnancy, occurrence of heterophil antibody and auto antibodies may also interfere the thyroid tests results. The interpretation of an unusual combination from thyroid stimulating hormonesuch as free thyroxin and tri-iodothyronine results needs confirmation of underlying condition for establishing the right diagnosis. This review is aimed to evaluate several factors which may influence the thyroid tests and interpretation.

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