Encephalopathy amino acids

R. O., Plasma amino acids in childhood epileptic encephalopathies, Epilepsy Res., 34, 221, 1999. 

Crystalline amino acid bulk solutions are supplied by various manufacturers in various concentrations (e.g., 3.5%, 5%, 7%, 8.5%, 10%, 15%, and 20%). Different formulations are tailored for specific age groups (e.g., adults and infants) and disease states (e.g., renal and liver disease). Specialized formulations for patients with renal failure contain higher proportions of essential amino acids. Formulas for patients with hepatic encephalopathy contain higher amounts of branched-chain and lower amounts of aromatic amino acids. However, these specialized formulations should not be used routinely in clinical practice because their efficacy has not been clearly demonstrated. Crystalline amino acid solutions have an acidic pH (pH = 5-7) and may contain inherent electrolytes (e.g., sodium, potassium, acetate, and phosphate). 

To this list of protein misfolding diseases can be added rare familial amyloidoses in which the mutated proteins have the classic amyloid fibril congophilic birefringence and cross-(3-sheet structure (Table 3). Many of these deposits have an impact on the central nervous system (TTR, cystatin, lysozyme) as well as on other organ systems. A newly described disease, familial British dementia, is associated with the deposition of Abri, a 34 amino acid, 4 kDa peptide cleaved from a 277 amino acid precursor sequence, the last 10 amino acids of which are not normally translated [52]. Familial encephalopathy with neuroserpin inclusion bodies (FENIB) is... 

Butterworth RF, Lavoie J, Peterson C, Cotman CW, Szerb J Excitatory amino acids and hepatic encephalopathy in Pomier Larargue G, Butterworth RF (eds) Hepatic Encephalopathy Pathophysiology and Treatment. Clifton, Humana Press, 1989, pp 417-433. 

Most untreated aminoacidopathies damage the brain. The pathophysiological factors that explain the encephalopathy remain unknown. Injury probably results from the accumulation of an amino acid or amino acid metabolite that is toxic to the nervous system, especially to the... 

Wu, X.Z., M. Yamada, T. Hobo, and S. Suzuki. 1989. Uranine sensitized chemiluminescence for alternative determinations of copper (II) and free cyanide by the flow injection method. Anal. Chem. 61 1505-1510. Yamamoto, H.A. 1989. Hyperammonemia, increased brain neutral and aromatic amino acid levels, and encephalopathy induced by cyanide in mice. Toxicol. Appl. Pharmacol. 99 415 120. 

Hepatic Increased branched-chain and decreased aromatic amino acids Patients with hepatic encephalopathy. 

Modified amino acid solutions are designed for patients with altered protein requirements associated with hepatic encephalopathy, renal failure, and metabolic stress or trauma. However, these solutions are expensive and their role in disease-specific PN regimens is controversial. 

Yamamoto H. 1989. Hyperammonemia, increased brain neutral and aromatic amino acid levels, and encephalopathy induced by cyanide in mice. Toxicol Appl Pharmacol 99 415-420. 

In addition to epilepsy, reduced GABA has been recorded in patients with unipolar depression, following alcohol withdrawal and in hepatic encephalopathy. The finding that the concentration of GABA is reduced in depression is unexpected as there is no evidence that the disorder is associated with an increased cortical excitability. One possibility is that the reduction in GABA is a reflection of a decreased availability in its excitatory amino acid precursor glutamate. 

This occurs when the quantity of aromatic amino acids entering the brain is larger than normal (as in hepatic encephalopathy), so that octopamine becomes a major tyrosine metabolite. The accumulation of octopamine induces coma. 

Know the names and modes of action of all proteolytic enzymes and their zymogens, if any, and the hormones that regulate protein digestion understand the mechanisms of amino acid absorption and their disorders understand amino acid traffic patterns in the bloodstream, including their changes in the various dietary states and hepatic encephalopathy. 

Bernardini P, Fischer JE. Amino acid imbalance and hepatic encephalopathy. Annu Rev Nutr 2 419-454, 1982. 

Primary carnitine deficiency is caused by a deficiency in the plasma-membrane carnitine transporter. Intracellular carnitine deficiency impairs the entry of long-chain fatty acids into the mitochondrial matrix. Consequently, long-chain fatty acids are not available for p oxidation and energy production, and the production of ketone bodies (which are used by the brain) is also impaired. Regulation of intramitochondrial free CoA is also affected, with accumulation of acyl-CoA esters in the mitochondria. This in turn affects the pathways of intermediary metabolism that require CoA, for example the TCA cycle, pyruvate oxidation, amino acid metabolism, and mitochondrial and peroxisomal -oxidation. Cardiac muscle is affected by progressive cardiomyopathy (the most common form of presentation), the CNS is affected by encephalopathy caused by hypoketotic hypoglycaemia, and skeletal muscle is affected by myopathy. 

Normal/reduced plasma concentration of BCAA muscle are relatively low in concentration as muscle metabolism continues normally. Aromatic amino acids which are metabolised hepatically are present in relatively high concentrations as the deranged liver is unable to perform its usual metabolic functions encephalopathy... 

Butterworth RF (2006) Metabolic Encephalopathies. In Siegel GJ, Albers RW, Brady ST, Price DL (eds) Basic neurochemistry, 7th edn. Elsevier, London, pp 593-602 Butterworth RF, Besnard AM (1990) Thiamine-dependent enzyme changes in temporal cortex of patients with Alzheimer s disease. Metab Brain Dis 5(4) 179-184 Butterworth RF, GaudreauC, Vincelette J, Bouigault AM, LamotheF, Nutini AM (1991) Thiamine deficiency and Wernicke s encephalopathy in AIDS. Metab Brain Dis 6(4) 207-212 Butterworth RF, Heroux M (1989) Effect of pyrithiamine treatment and subsequent thiamine rehabilitation on regional cerebral amino acids and thiamine-dependent enzymes. J Neurochem 52(4) 1079-1084... 

Bombardieri, G., Gigli, G.L., Bern di, L., Ferri, R., Grass , C., Milani, A. Visual evoked potential recordings in hepatic encephalopathy and their variations during branched chain amino-acid treatment. Hepato-Gastroenterol. 1985 32 3—7... 

Joelsson, B., Asinnd, U., Hultberg, B., Alwmark, A., Gullstrand, P., Bengmark, S. Portal-systemic encephalopathy. Influence of shunt surgery and relations to serum amino acids. Scand. X Gastroenterol. 1986 21 900-906... 

Knudsen, GJM., Schmidt, J., Almdal, T., Paulson, OJI., Vllstru H. Passage of amino acids and glucose across the blood-brain barrier in patients with hepatic encephalopathy. Hepatology 1993 17 987—992... 

Marchesini, G., Zoli, M., Dondi, C., Cecchini, L., Angiolini, A., Bian-chi, F.B., Pisi, E. Prevalence of subclinical hepatic encephalopathy in cirrhotics and relationship to plasma amino acid imbalance. Dig. Dis. Sci. 1980 25 763-768... 

Eriksson, L.S., Conn, H.O. Branched-chain amino acids in the management of hepatic encephalopathy an analysis of variants. Hepatology 1989 10 228 - 246... 

Freund, H., Yoshimura, N., Fischer, J.E. Chronic hepatic encephalopathy. Long-term therapy with a branched-chain amino-acid-enriched elemental diet. X. Amer. Med. Ass. 1979 242 347-349... 

Higuchi, K., Shimizu, Y., Nambu, S., Miyabayashi, C., Takahara, T., Saito, S., Hioki, O., Kuwabara, Y., Watanabe, A. Effects of an infusion of branched-chain amino acids on neurophysiological and psychometric testings in cirrhotic patients with mild hepatic encephalopathy. 

Horst, D., Grace, N.D., Conn, H.O., Schiff, E., Schenker, S., Viteri, A., Law, D., Atterbury, C.E. Comparison of dietary protein with an oral branched chain-enriched amino acid supplement in chronic portal-systemic encephalopathy a randomized controlled trial Hepatology 1984 4 279 - 287... 

Naylor, C.D., O Rourke, K., Detsky, A.S., Baker, J.R Parenteral nutrition with branched-chain amino acids in hepatic encephalopathy. A meta-analysis. Gastroenterology 1989 97 1033-1042... 

Plauth, M., Egberts, E.-H., Hamster, W., Torok, M., MuBer, P.H., Brand, O., Flirst, R, Dolle, W. Long-term treatment of latent portosystemic encephalopathy with branched-chain amino acids. A doubleblind placebo-controlled crossover study. X Hepatol. 1993 17 308-314... 

The cirrhosis patient is in a vicious circle regarding protein metabolism cirrhosis hepatic encephalopathy protein restriction malnutrition catabolism Thus, prolonged protein restriction and catabolism may considerably worsen the prognosis of cirrhosis. In this hazardous situation, the dietary and therapeutic use of branched-chain amino acids (BCAA), i.e. valine, leucine and isoleucine, is a logical therapeutic intervention. 

The indication for administering BCAA in patients with hepatic encephalopathy to compensate amino-acid imbalance was proposed by J.E. Fischer et al. in 1974, and implemented parenterally. However, oral application of BCAA for an adequate treatment period also has beneficial effects on cirrhosis and HE (7.) improvement in protein tolerance and the nutritional condition, (2.) improvement in cerebral functions (II8, 122), probably due to an amelioration of liver function, (2.) stimulation of ammonia detoxification with a positive nitrogen balance (118), (4.) reduction in or normalization of AAA levels, and (5.) promotion of glutamine synthesis with a favourable effect on the cells of the immune system and on renal function. By means of BCAA, it was possible to prolong the survival time and delay the occurrence of liver failure in rats with CC -induced cirrhosis. (123, 126) However, there are diverging results, which need further clarification. In principle, the use of BCAA is considered to be a necessary form of supplementary treatment for catabolic metabolism in cirrhosis (124,125, 127, 128, 130-132), in (also latent) HE and after curative resection of hepatocellular carcinoma. (I2l) (s. p. 280)... 

Latent encephalopathy, detectable by psychometric tests (s. p. 202), is frequent experience has shown that it can rapidly become manifest. Of the urea-cycle amino acids suitable for therapy, ornithine aspartate has proved the most successful - also as an i.v. infusion in the postoperative phase, (s. pp 279, 733)... 

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