Radiation Effects on Cyclic AMP, Cyclic GMP, and Amino Acid Levels in the CSF of the Primate

1981 ◽  
Vol 87 (1) ◽  
pp. 198 ◽  
Author(s):  
G. N. Catravas ◽  
S. J. Wright ◽  
P. J. Trocha ◽  
J. Takenaga
2019 ◽  
Author(s):  
Todd A. Wright ◽  
Lucy Jiang ◽  
James J. Park ◽  
Wyatt A. Anderson ◽  
Ge Chen ◽  
...  

ABSTRACT3’,3’-cyclic GMP-AMP (cGAMP) is the third cyclic dinucleotide (CDN) to be discovered in bacteria. No activators of cGAMP signaling have yet been identified, and the signaling pathways for cGAMP have appeared narrowly distributed based upon the characterized synthases, DncV and Hypr GGDEFs. Here we report that the ubiquitous second messenger cyclic AMP (cAMP) is an activator of the Hypr GGDEF enzyme GacB from Myxococcus xanthus. Furthermore, we show that GacB is inhibited directly by cyclic di-GMP, which provides evidence for cross-regulation between different CDN pathways. Finally, we reveal that the HD-GYP enzyme PmxA is a cGAMP-specific phosphodiesterase (GAP) that promotes resistance to osmotic stress in M. xanthus. A signature amino acid change in PmxA was found to reprogram substrate specificity and was applied to predict the presence of non-canonical HD-GYP phosphodiesterases in many bacterial species, including phyla previously not known to utilize cGAMP signaling.


1983 ◽  
Vol 50 (04) ◽  
pp. 804-809 ◽  
Author(s):  
Torstein Lyberg

SummaryHuman monocytes in vitro respond to various agents (immune complexes, lectins, endotoxin, the divalent ionophore A 23187, 12-0-tetradecanoyl-phorbol 13-acetate [TPA], purified protein derivative [PPD] of Bacille Calmette-Guerin) with an increased synthesis of the protein component of thromboplastin. The effect of cyclic AMP and cyclic GMP on this response has been studied. Dibutyryl-cyclic AMP, prostaglandin E1 and the phosphodiesterase inhibitors 3-butyl-1-methyl-xanthine (MIX) and rac -4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (Ro 201724), separately and in combination have a pronounced inhibitory effect on the response to immune complexes and PPD, and a moderate effect on the response to endotoxin and lectins. The effect on TPA response and on the response to A 23187 was slight. Dibutyryl-cyclic GMP (1 mM) gave a slight inhibition of the TPA arid IC response, but had essentially no effect on the response to other inducers. The intracellular cAMP level increased when monocytes were incubated with IC, TPA or A 23187 followed by a decrease to basal levels within 1-2 hr, whereas lectin (PHA) and PPD did not induce such changes. The cAMP response to endotoxin varied. Stimulation with IC induced an increase in monocyte cGMP levels, whereas the other stimulants did not cause such changes.


1979 ◽  
Vol 29 ◽  
pp. 85
Author(s):  
Nobuyoshi Yoshida ◽  
Kohtaro Taniyama ◽  
Chikako Tanaka

1986 ◽  
Vol 111 (2) ◽  
pp. 225-232 ◽  
Author(s):  
S. A. Burchill ◽  
A. J. Thody

ABSTRACT Skin tyrosinase activity increases during hair growth in C3H–HeA*vy mice and reaches higher levels in young (30- to 35-day-old) mice when the hair follicular melanocytes synthesize the black pigment, eumelanin, than in older (6-month-old) mice when they produce the golden yellow pigment, phaeomelanin. To examine the regulation of the melanocytes at these different stages we have compared the effect of α-MSH and other agents that act, through cyclic AMP-dependent mechanisms, on skin tyrosinase activity in both young and old mice during hair growth, initiated by plucking. Daily administration of α-MSH, isoprenaline or theophylline increased coat darkness, and skin tyrosinase activity in the younger mice 7–9 days after plucking, but they were ineffective in the older mice. Similarly α-MSH, 8-bromo-cyclic AMP or theophylline increased tyrosinase activity in skin explants from the younger mice incubated for up to 24 h but had no effect in explants from older mice. Cyclic GMP had no effect on tyrosinase activity in skin explants from both young and old mice. It is suggested that whereas cyclic AMP-dependent mechanisms may operate to regulate tyrosinase activity in the hair follicular melanocytes of younger mice that produce eumelanin these systems may not operate in the older mice when these melanocytes synthesize phaeomelanin. Phaeomelanin synthesis, unlike that of eumelanin, may not depend upon tyrosinase and its regulation by cyclic AMP and this could explain the low levels of this enzyme in the skin and its failure to respond to α-MSH and other activators of the cyclic AMP system during periods of phaeomelanin production. J. Endocr. (1986) 111, 225–232


2021 ◽  
pp. 101327
Author(s):  
Maria Camila Alfaro-Wisaquillo ◽  
Edgar O. Oviedo-Rondón ◽  
Hernan A. Cordova-Noboa ◽  
Justina V. Caldas ◽  
Gustavo A. Quintana-Ospina ◽  
...  

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 76-76
Author(s):  
Ron Ball ◽  
Crystal L Levesque ◽  
D J Cadogan

Abstract Most sows are fed a constant energy and amino acid supply throughout gestation, in line with the recommendations of most authorities and swine genetic companies. These recommendations for sow feeding have seen little change in decades, despite the many ways that sows have changed dramatically in reproductive performance. Beginning in about the year 2000, sow litter size has steadily increased as a result of genetic selection. With this increase in litter number has been a steady decline in birth weight, and the resulting negative effects of lower birthweight on subsequent piglet performance. Many experiments using so-called ‘bump’ feeding, or increased energy intake in late gestation, have been conducted in attempts to arrest this decline in birthweight and piglet performance. Generally, these experiments have shown little to no improvement in birthweight and often have negative effects on sow feed intake during gestation. These experiments have ignored the fact that the energy:amino acid ratios (lysine, threonine, isoleucine, tryptophan) in late gestation are different than during early and mid-gestation. In recent research in Australia we hypothesised that rapidly increasing essential amino acid levels in late gestation would increase birth weight and potentially improve subsequent reproductive performance. Three hundred and thirty-four multiparous PIC sows (average parity 3.6, average LW 261 kg) were housed in a dynamic gestation pen after mating and randomly assigned to one of two diet regimes. Two 13.5 MJ/kg DE gestation diets were formulated and created by blending in an ESF. The Control diet contained 0.48 g SID lysine per MJ DE and SID threonine, methionine+ cysteine, isoleucine and tryptophan at 68%, 65%, 58% and18% of SID lysine and offered at 2.2kg/day from d 28 to d 110. Sow were then moved to the farrowing house and placed on a lactation diet at 3.5kg/d. The Treatment diet contained 0.55 g SID lysine/MJ DE and SID threonine, methionine+cysteine, isoleucine and tryptophan at 78%, 65%, 60% and 20% of SID lysine and offered at 2.1kg/d from d 28 to d 85 and then increased to 2.4 kg/d to d 110 d. Increasing essential amino acid levels in late gestation increased gestational weight gain (5.6 kg, P=0.004), increased total litter birth weight (1.25 kg, P=0.003), and increased the birthweight of liveborn pigs from 1.286 to 1.329 kg, (P=0.04). There was no significant effect on the total number born or born alive. Piglet performance is not available because this commercial farm practices cross-fostering. Effects of continuation of this feeding regime in the same sows during subsequent parities is currently being evaluated.


1949 ◽  
Vol 177 (1) ◽  
pp. 91-95 ◽  
Author(s):  
Choh.Hao. Li ◽  
I. Geschwind ◽  
Herbert M. Evans
Keyword(s):  

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Eva-Maria Sedlmeier ◽  
Dorothy M. Meyer ◽  
Lynne Stecher ◽  
Manuela Sailer ◽  
Hannelore Daniel ◽  
...  

Abstract Background Previously, we revealed sexually dimorphic mRNA expression and responsiveness to maternal dietary supplementation with n-3 long-chain polyunsaturated fatty acids (LCPUFA) in placentas from a defined INFAT study subpopulation. Here, we extended these analyses and explored the respective placental microRNA expression, putative microRNA-mRNA interactions, and downstream target processes as well as their associations with INFAT offspring body composition. Results We performed explorative placental microRNA profiling, predicted microRNA-mRNA interactions by bioinformatics, validated placental target microRNAs and their putative targets by RT-qPCR and western blotting, and measured amino acid levels in maternal and offspring cord blood plasma and placenta. microRNA, mRNA, protein, and amino acid levels were associated with each other and with offspring body composition from birth to 5 years of age. Forty-six differentially regulated microRNAs were found. Validations identified differential expression for microRNA-99a (miR-99a) and its predicted target genes mTOR, SLC7A5, encoding L-type amino acid transporter 1 (LAT1), and SLC6A6, encoding taurine transporter (TauT), and their prevailing significant sexually dimorphic regulation. Target mRNA levels were mostly higher in placentas from control male than from female offspring, whereas respective n-3 LCPUFA responsive target upregulation was predominantly found in female placentas, explaining the rather balanced expression levels between the sexes present only in the intervention group. LAT1 and TauT substrates tryptophan and taurine, respectively, were significantly altered in both maternal plasma at 32 weeks’ gestation and cord plasma following intervention, but not in the placenta. Several significant associations were observed for miR-99a, mTOR mRNA, SLC7A5 mRNA, and taurine and tryptophan in maternal and cord plasma with offspring body composition at birth, 1 year, 3 and 5 years of age. Conclusions Our data suggest that the analyzed targets may be part of a sexually dimorphic molecular regulatory network in the placenta, possibly modulating gene expression per se and/or counteracting n-3 LCPUFA responsive changes, and thereby stabilizing respective placental and fetal amino acid levels. Our data propose placental miR-99, SLC7A5 mRNA, and taurine and tryptophan levels in maternal and fetal plasma as potentially predictive biomarkers for offspring body composition.


2021 ◽  
Vol 403 ◽  
pp. 108187
Author(s):  
Donald. A Godfrey ◽  
William B. Farms ◽  
Sharon Polensek ◽  
Jon D. Dunn ◽  
Timothy G. Godfrey

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