Influences of Amino Acids on the Circadian Rhythms of Brain Neurotransmitters

Author(s):  
C. Angelova ◽  
L. Balabanski
1984 ◽  
Vol 247 (2) ◽  
pp. E276-E283
Author(s):  
D. R. Strombeck ◽  
D. Harrold ◽  
Q. R. Rogers

Investigations were made on the effects of catecholamine (Cat) infusions with and without ammonia (NH3) on plasma and brain amino acids (AA) and brain neurotransmitters in dogs. Groups of four dogs were infused for 5 h with epinephrine (E), epinephrine + norepinephrine (E + NE), epinephrine + norepinephrine with NH3 during h 4 and 5 (E + NE + NH3), epinephrine + norepinephrine + tryptophan with NH3 during h 4 and 5 (T + E + NE + NH3), or saline (C). Cat decreased (P less than 0.05) plasma Gly, Thr, Lys, Pro, Val, Ser, Arg, Leu, Trp, Phe, Asn, Tyr, Met, Ile, Cit, and Asp. The decreases at h 3 for all were to a mean of 45% of 0 h and were associated with no changes in plasma insulin or glucagon. Cat increased plasma Tau and Orn. Of the most abundant brain AA (82% of total), E + NE + NH3 had no effect (GABA, Asp, Gly, Ala, p-ethanolamine) or increased (Glu, Gln, Tau) brain levels. These AA were unchanged by Cat alone. Of the remaining brain AA, most were decreased by Cat (7 of 16, P less than 0.05) and E + NE + NH3 increased brain Trp but had no effect on brain serotonin, 5-hydroxyindoleacetic acid, or NE. Cat changed plasma AA in a way similar to changes produced by NH3 infusion and seen with hepatic insufficiency due to portacaval shunts and nitrosamine-induced pathology. Cat reduced brain AA levels, and this was partially restored by NH3.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Md Abu Bakkar Siddik ◽  
Masoud Zabet Moghaddam ◽  
Vijay Hegde ◽  
Andrew Shin

Abstract Objectives Alzheimer's disease (AD) is an irreversible neurodegenerative disorder that is the third leading cause of mortality in the US. AD brain is mainly characterized by accumulated plaques and tangles and diminished neurotransmitters. AD is strongly associated with type 2 diabetes (T2D). Emerging studies suggest that branched-chain amino acids (BCAAs), the essential amino acids we need to obtain from food, are involved in the pathogenesis of insulin resistance and T2D. In support of this concept, BCAA degradation is impaired in obese and/or diabetic individuals, and BCAA supplementation leads to insulin resistance and perturbed glycemic control. It is currently unknown if similar defective BCAA metabolism exists in AD patients. Since BCAAs along with aromatic amino acids are critical for production and maintenance of brain neurotransmitters, here we tested if BCAA metabolism in liver – an organ with the highest BCAA degradation activity – is impaired in AD. Methods Eight month-old wildtype or AD transgenic mice were fed a standard chow diet until sacrifice. Serum BCAA levels were measured by BCAA assay, and proteins and genes related to BCAA metabolism in liver were determined by western blot and RT-qPCR, respectively. Serum BCAA profile of healthy or AD individuals were assessed by metabolomics analysis. Results The activity of branched-chain α-keto acid dehydrogenase (BCKDH), the rate-limiting enzyme in BCAA degradation pathway, in liver was significantly suppressed in AD mice compared to wildtypes as evidenced by the protein expression and its phosphorylated, inactive, state. This is supported by increased hepatic BCKDH Kinase at both protein and gene levels in AD mice. Serum BCAAs and/or their metabolites were higher in both AD mice and humans compared to healthy controls, indicating impaired BCAA metabolism. Conclusions Our findings suggest that hepatic BCAA catabolism is impaired in AD mice. This may lead to high plasma BCAAs and their metabolites that can potentially contribute to the imbalance of brain neurotransmitters and development of AD or related dementia. A longitudinal assessment of BCAA metabolism will allow us to determine if they play a predictive, diagnostic, and/or causal role in the development of AD. Funding Sources NIH DK099463, Wylie Briscoe Fund, Texas Tech University.


1974 ◽  
Vol 29 (11-12) ◽  
pp. 767-772 ◽  
Author(s):  
B. E. Leonard ◽  
V Neuhoff ◽  
Sally Tonge

Abstract The formation of dansyl derivatives of amino acids, 5-hydroxyindoleacetic acid and histamine and their separation on polyamide plates provided a reliable and sensitive method for studying circadian changes in single pineal and pituitary glands of the rat. There appears to be no cor­relation between the circadian changes in concentrations of these substances in the pineal and pituitary glands. Chronically administered D-amphetamine altered the circadian rhythms of 5-amino acids in the pituitary, including the putative transmitters taurine, glycine and glutamate; in the pineal gland only the rhythmical changes of lysine and 5-hydroxyindoleacetic acid were affected.


Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3091
Author(s):  
Omar A. Ahmed-Farid ◽  
Ayman S. Salah ◽  
Mohamed Abdo Nassan ◽  
Mahmoud S. El-Tarabany

Guanidinoacetic acid (GA) is a natural precursor of creatine in the body and is usually used to improve the feed conversion and cellular energy metabolism of broiler chickens. The objective was to elucidate the effect of dietary supplementation of GA on carcass yield, muscle amino acid profile, and concentrations of brain neurotransmitters in laying hens. In total, 128 72-week-old ISA Brown laying hens were assigned to four equal groups (32 birds, eight replicates per group). The control group (T1) was fed a basal diet with no supplements, while the other experimental groups were fed a basal diet supplemented with 0.5 (T2), 1.0 (T3), and 1.5 (T4) g GA kg−1 diet. The T3 and T4 groups showed higher hen-day egg production and carcass yield compared to the control group (p = 0.016 and 0.039, respectively). The serum creatine level increased linearly with the increased level of dietary GA (p = 0.007). Among the essential amino acids of breast muscle, a GA-supplemented diet linearly increased the levels of leucine, isoleucine, phenylalanine, methionine, and threonine in the breast (p = 0.003, 0.047, 0.001, 0.001, and 0.015, respectively) and thigh (p = 0.026, 0.001, 0.020, 0.009, and 0.028, respectively) muscles. GA supplementation linearly reduced the level of brain serotonin compared to the control group (p = 0.010). Furthermore, supplementation of GA in the diet of laying hens linearly increased the level of brain dopamine (p = 0.011), but reduced the level of brain Gamma-aminobutyric acid (p = 0.027). Meanwhile, the concentration of brain nitric oxide did not differ between the experimental groups (p = 0.080). In conclusion, the dietary supplementation of GA may improve the carcass yield and levels of essential amino acids in the breast muscles, as well as the brain neurotransmitters in aged laying hens.


2018 ◽  
Vol 16 (1) ◽  
Author(s):  
Cathalijn H. C. Leenaars ◽  
Jennifer Freymann ◽  
Koen Jakobs ◽  
Julia M. L. Menon ◽  
Thomas J. Van Ee ◽  
...  

1997 ◽  
Vol 161 ◽  
pp. 505-510
Author(s):  
Alexandra J. MacDermott ◽  
Laurence D. Barron ◽  
Andrè Brack ◽  
Thomas Buhse ◽  
John R. Cronin ◽  
...  

AbstractThe most characteristic hallmark of life is its homochirality: all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. We therefore suggest that a search for extra-terrestrial life can be approached as a Search for Extra- Terrestrial Homochirality (SETH). The natural choice for a SETH instrument is optical rotation, and we describe a novel miniaturized space polarimeter, called the SETH Cigar, which could be used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. We believe that homochirality may be found in the subsurface layers on Mars as a relic of extinct life, and on other solar system bodies as a sign of advanced pre-biotic chemistry. We discuss the chiral GC-MS planned for the Roland lander of the Rosetta mission to a comet and conclude with theories of the physical origin of homochirality.


1997 ◽  
Vol 161 ◽  
pp. 179-187
Author(s):  
Clifford N. Matthews ◽  
Rose A. Pesce-Rodriguez ◽  
Shirley A. Liebman

AbstractHydrogen cyanide polymers – heterogeneous solids ranging in color from yellow to orange to brown to black – may be among the organic macromolecules most readily formed within the Solar System. The non-volatile black crust of comet Halley, for example, as well as the extensive orangebrown streaks in the atmosphere of Jupiter, might consist largely of such polymers synthesized from HCN formed by photolysis of methane and ammonia, the color observed depending on the concentration of HCN involved. Laboratory studies of these ubiquitous compounds point to the presence of polyamidine structures synthesized directly from hydrogen cyanide. These would be converted by water to polypeptides which can be further hydrolyzed to α-amino acids. Black polymers and multimers with conjugated ladder structures derived from HCN could also be formed and might well be the source of the many nitrogen heterocycles, adenine included, observed after pyrolysis. The dark brown color arising from the impacts of comet P/Shoemaker-Levy 9 on Jupiter might therefore be mainly caused by the presence of HCN polymers, whether originally present, deposited by the impactor or synthesized directly from HCN. Spectroscopic detection of these predicted macromolecules and their hydrolytic and pyrolytic by-products would strengthen significantly the hypothesis that cyanide polymerization is a preferred pathway for prebiotic and extraterrestrial chemistry.


Author(s):  
E.M. Kuhn ◽  
K.D. Marenus ◽  
M. Beer

Fibers composed of different types of collagen cannot be differentiated by conventional electron microscopic stains. We are developing staining procedures aimed at identifying collagen fibers of different types.Pt(Gly-L-Met)Cl binds specifically to sulfur-containing amino acids. Different collagens have methionine (met) residues at somewhat different positions. A good correspondence has been reported between known met positions and Pt(GLM) bands in rat Type I SLS (collagen aggregates in which molecules lie adjacent to each other in exact register). We have confirmed this relationship in Type III collagen SLS (Fig. 1).


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