EFFECTS OF LUTEINIZING HORMONE AND NICOTINAMIDE ADENINE DINUCLEOTIDE PHOSPHATE ON SYNTHESIS OF PROGESTATIONAL STEROIDS BY RABBIT OVARIAN TISSUE IN VITRO

1966 ◽  
Vol 35 (1) ◽  
pp. 65-73 ◽  
Author(s):  
J. H. DORRINGTON ◽  
R. KILPATRICK
Keyword(s):  
Luteinizing Hormone ◽  
Nicotinamide Adenine Dinucleotide ◽  
Ovarian Tissue ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Nicotinamide Adenine ◽  
Steroid Synthesis ◽  
Activity Measurements ◽  
Progesterone Synthesis ◽  
Stimulation Of

SUMMARY Luteinizing hormone (LH) stimulated synthesis of both progesterone and 20α-hydroxypregn-4-en-3-one by rabbit ovarian tissue in vitro. Progesterone synthesis was stimulated by nicotinamide adenine dinucleotide phosphate (NADP), but 20α-hydroxypregn-4-en-3-one production was only slightly affected by NADP compared with the effect of LH. When NADP was added with glucose-6-phosphate (G-6-P) or 6-phospho-gluconate (6-P-G), no apparent stimulation of progestational steroid synthesis occurred. Specific activity measurements suggested that stimulation of synthesis was masked by increased conversion of progestational steroids to other products. When NADP and submaximal concentrations of LH were used together, potentiation rather than addition of effects on progesterone synthesis was found, and addition of effects with supramaximal concentrations of LH. No potentiation was found when NADP was replaced by NADP and G-6-P or 6-P-G, or by NADPH2. NADP, unlike LH, caused striking stimulation of progesterone synthesis by separated corpora lutea. It is suggested that the present results provide further support for the view that the actions of LH and NADP are related.

Control of progesterone biosynthesis in the bovine corpus luteum: effects of luteinizing hormone and of reduced nicotinamide–adenine dinucleotide phosphate in vitro

1968 ◽  
Vol 46 (9) ◽  
pp. 1137-1145 ◽  
Author(s):  
David T. Armstrong ◽  
Donald L. Black
Keyword(s):  
Luteinizing Hormone ◽  
Corpus Luteum ◽  
Nicotinamide Adenine Dinucleotide ◽  
Specific Activity ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Stimulatory Action ◽  
Bovine Corpus Luteum ◽  
Progesterone Synthesis ◽  
Reduced Nicotinamide Adenine Dinucleotide

The effects of luteinizing hormone (LH) and of reduced nicotinamide–adenine dinucleotide phosphate (NADPH) upon in vitro progesterone synthesis by bovine corpus luteum slices incubated for varying periods of time have been examined. The increased net synthesis of progesterone caused by LH was accompanied by markedly increased incorporation of acetate-1-14C into progesterone and decreased incorporation of acetate-1-14C into cholesterol. In most experiments, especially at longer incubation times, exogenous NADPH decreased incorporation of acetate-1-14C into progesterone. The effect of NADPH on incorporation of acetate-1-14C into cholesterol was variable, increasing cholesterol specific activity in some experiments and decreasing it in others. At all time intervals in all experiments, the specific activity of progesterone synthesized was greater than that of the cholesterol remaining in the tissue at the end of the interval. With increasing duration of incubations, specific activity of the progesterone synthesized became increasingly greater than that of cholesterol remaining at the end of the incubation period. These findings suggest that newly synthesized cholesterol is utilized for progesterone formation without coming into equilibrium with a large portion of the intracellular cholesterol pool. Experiments with radioactive cholesterol in vitro indicated that a significant amount of conversion of this precursor occurred in the incubation medium by enzymes which had leaked out of the tissue, and this conversion was strikingly stimulated by exogenous NADPH but not by LH. Rates of progesterone synthesis were greatest in shortest incubations, declining as incubation periods were extended. Highly significant correlations were observed between the increments, caused by LH, in net synthesis (mass) of progesterone, incorporation of acetate-1-14C into progesterone, and lactic acid production. Inhibition by puromycin of the stimulatory action of LH upon progesterone synthesis failed to prevent the stimulatory action of this gonadotropin upon glycolysis. These findings indicate that the stimulation of glycolysis is not a consequence of stimulated progesterone synthesis but may be related to the stimulatory action of LH upon 3′,5′-AMP production.

NAD(P)H oxidase–dependent platelet superoxide anion release increases platelet recruitment

Blood ◽  
2002 ◽  
Vol 100 (3) ◽  
pp. 917-924 ◽  
Author(s):  
Florian Krötz ◽  
Hae Young Sohn ◽  
Torsten Gloe ◽  
Stefan Zahler ◽  
Tobias Riexinger ◽  
...  
Keyword(s):  
Nicotinamide Adenine Dinucleotide ◽  
Thrombus Formation ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Human Platelets ◽  
Nicotinamide Adenine ◽  
Irreversible Aggregation ◽  
Reduced Nicotinamide Adenine Dinucleotide ◽  
Specific Peptide

Abstract Platelets, although not phagocytotic, have been suggested to release O2−. Since O2−-producing reduced nicotinamide adenine dinucleotide (phosphate) (NAD(P)H) oxidases can be specifically activated by certain agonists and are found in several nonphagocytotic tissues, we investigated whether such an enzyme is the source of platelet-derived O2−. We further studied which agonists cause platelet O2−release and whether platelet-derived O2− influences thrombus formation in vitro. Collagen, but not adenosine 5′-diphosphate (ADP) or thrombin, increased O2− formation in washed human platelets. This was a reduced nicotinamide adenine dinucleotide (NADH)–dependent process, as shown in platelet lysates. Consistent with a role of a platelet, NAD(P)H oxidase expression of its subunits p47phox and p67phoxand inhibition of platelet O2− formation by diphenylene-iodoniumchloride (DPI) and by the specific peptide-antagonist gp91ds-tat were observed. Whereas platelet-derived O2− did not influence initial aggregation, platelet recruitment to a preformed thrombus following collagen stimulation was significantly attenuated by superoxide dismutase (SOD) or DPI. It was also inhibited when ADP released during aggregation was cleaved by the ectonucleotidase apyrase. ADP in supernatants of collagen-activated platelets was decreased in the presence of SOD, resulting in lower ADP concentrations available for recruitment of further platelets. Exogenous O2−increased ADP- concentrations in supernatants of collagen-stimulated platelets and induced irreversible aggregation when platelets were stimulated with otherwise subthreshold concentrations of ADP. These results strongly suggest that collagen activation induces NAD(P)H oxidase–dependent O2− release in platelets, which in turn enhances availability of released ADP, resulting in increased platelet recruitment.

scholarly journals IL8 Drives an Elaborate Signal Transduction Process for CD38 to Produce NAADP from NAAD and NADP+ in Endolysosomes to Effect Cell Migration

2020 ◽  
Author(s):  
Tae-Sik Nam ◽  
Dae-Ryoung Park ◽  
So-Young Rah ◽  
Tae-Gyu Woo ◽  
Hun Taeg Chung ◽  
...  
Keyword(s):  
Cell Migration ◽  
Nicotinic Acid ◽  
Nicotinamide Adenine Dinucleotide ◽  
Connexin 43 ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Nicotinamide Adenine ◽  
Type Ii ◽  
Lymphokine Activated Killer Cells ◽  
Base Exchange

AbstractNicotinic acid adenine dinucleotide phosphate (NAADP) is an obligate driver of calcium signaling whose formation from other metabolites of nicotinamide adenine dinucleotide (NAD+) has remained elusive. In vitro, CD38-mediated NAADP synthesis requires an acidic pH and a nonphysiological concentration of nicotinic acid (NA). We discovered that the type II membrane form of CD38 catalyzes synthesis of NAADP by exchanging the nicotinamide moiety of nicotinamide adenine dinucleotide phosphate (NADP+) for the NA group of nicotinic acid adenine dinucleotide (NAAD) inside endolysosomes of interleukin 8 (IL8)-treated lymphokine-activated killer cells. Upon IL8 stimulation, cytosolic NADP+ is transported to acidified endolysosomes via connexin 43 via cAMP-EPAC-RAP1-PP2A signaling. Luminal CD38 then performs a base exchange reaction with the donor NA group deriving from NAAD, produced by newly described endolysosomal activities of NA phosphoribosyltransferase and NMN adenyltransferase 3. Thus, the membrane organization of endolysosomal CD38, a signal-mediated transport system for NADP+ and luminal NAD+ biosynthetic enzymes integrate signals from a chemokine and cAMP to specify the spatiotemporal mobilization of calcium to drive cell migration.

scholarly journals Incorporation of L-[1-14C]leucine into protein by liver postmitochondrial supernatant: opposing effects of preincubated nicotinamide-adenine dinucleotide phosphate and 4-dimethylamino-3′-methylazobenzene

1975 ◽  
Vol 146 (2) ◽  
pp. 505-507 ◽  
Author(s):  
N P Madsen ◽  
J E Labuc
Keyword(s):  
Nicotinamide Adenine Dinucleotide ◽  
Nicotinamide Adenine Dinucleotide Phosphate ◽  
Nicotinamide Adenine ◽  
Free Protein ◽  
A Cell ◽  
Opposing Effects ◽  
Stimulation Of

Combination of preincubated drug-metabolizing medium containing NADP+ with a cell-free protein-synthesizing system resulted in marked stimulation of incorporation of L-[1-14C]leucine into protein. Addition of 4-dimethylamino-3′-methylazobenzene, present and previously preincubated in the drug-metabolizing medium, decreased this effect.

REPTILIAN OVARIAN STEROIDOGENESIS AND THE INFLUENCE OF MAMMALIAN GONADOTROPHINS (FOLLICLE-STIMULATING HORMONE AND LUTEINIZING HORMONE) IN VITRO

1974 ◽  
Vol 62 (2) ◽  
pp. 267-275 ◽  
Author(s):  
S. W. C. CHAN ◽  
I. P. CALLARD
Keyword(s):  
Luteinizing Hormone ◽  
Ovarian Function ◽  
Cholesterol Metabolism ◽  
Ovarian Tissue ◽  
Follicle Stimulating Hormone ◽  
Sampling Period ◽  
Steroid Synthesis ◽  
Stimulating Hormone

SUMMARY The synthesis of steroids from [7α-3H]cholesterol, [7α-3H]pregnenolone and [7α-3H]progesterone by lizard and turtle ovarian tissues in vitro was studied. Progesterone, 17α-hydroxyprogesterone, dehydroepiandrosterone, androstenedione, testosterone, oestrone and oestradiol were identified as products. In the turtle (Pseudemys), conversion of pregnenolone to progesterone was efficient, but transformation of progesterone to other steroids was relatively slow as indicated by the accumulation of progesterone over the incubation period. In Dipsosaurus, accumulation of radioactivity was greatest in testosterone, the quantities of which continued to increase at each sampling period. The rate of utilization of pregnenolone as a substrate was similar for the two species studied and the quantities of oestrone and oestradiol formed were lower in Pseudemys. The use of progesterone as precursor by Dipsosaurus ovarian tissue revealed a similar pattern of Δ4-steroid metabolism to that obtained with pregnenolone as precursor. The effects of addition of purified follicle-stimulating hormone (FSH) and luteinizing hormone (LH) on the metabolism of [14C]cholesterol in vitro was studied using Pseudemys follicular tissue. The pattern of cholesterol metabolism was similar to that for pregnenolone in this species. The synthesis of pregnenolone, progesterone, dehydroepiandrosterone and androstenedione in vitro was significantly enhanced in the presence of LH. Follicle-stimulating hormone had no effect on steroid synthesis except for a decrease of androstenedione formation. The stimulatory effect of LH on steroidogenesis in vitro is discussed in relation to the literature suggesting that mammalian FSH, but not LH, stimulates all phases of reptilian ovarian function when injected in vivo.

PROGESTERONE SYNTHESIS IN RESPONSE TO LUTEINIZING HORMONE BY RAT OVARIAN TISSUE IN VITRO

1971 ◽  
Vol 49 (3) ◽  
pp. 471-478 ◽  
Author(s):  
J. WATSON
Keyword(s):  
Ascorbic Acid ◽  
Luteinizing Hormone ◽  
Ovarian Tissue ◽  
Large Numbers ◽  
Progesterone Synthesis ◽  
Immature Rats ◽  
Increased Sensitivity ◽  
High Degree ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY A bioassay for luteinizing hormone (LH) activity is described. The method depends on progesterone synthesis by pooled, sliced rat ovarian tissue in vitro, the ovaries being obtained from immature rats pretreated with pregnant mare serum gonadotrophin. The main advantage of the method is its increased sensitivity compared with the commonly used ovarian ascorbic acid depletion assay, its high degree of precision, and the fact that it allows the use of large numbers of well randomized samples from a small group of animals.

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