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Adenosine kinase deficiency
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
The differential diagnosis of hypermethioninemia includes, in addition to ADK deficiency, deficiencies of methionine adenosyltransferase (MAT I/III), glycine N-Methyltransferase (GNMT), S-adenosylhomocysteine hydrolase (SAHH), and cystathionine β-synthase (CBS) (Chapter 18). Elevated methionine concentrations are also commonly present in hepatic disease and in hepatorenal tyrosinemia and citrullinemia type 2 as well as other nonmetabolic liver diseases, but then hypermethioninemia is rarely found in isolation but rather in combination with elevated tyrosine and phenylalanine.
Inorganic Chemical Pollutants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Plasma tHcys was significantly inversely associated with %MMA in males, and its estimated correlation with %DMA was positive, although not statistically significant among both males and females. These associations are opposite of those in adults. Although additional studies will be required to clarify the mechanism underlying these observations, the findings raise the question of whether there may be differences in the fundamental regulation of one-carbon metabolism between children and adults. Theoretically, one would expect overall upregulation of one-carbon metabolism during periods of rapid growth to meet the high demands for protein and DNA synthesis. In rats and rabbits, glycine-N-methyltransferase (GNMT) activity levels are very low at birth and increase continuously with age.782 Since GNMT, which catalyzes the nonessential methylation of glycine to sarcosine, competes for SAM and generates SAH, lower activity during periods of rapid growth may be one mechanism whereby increased requirements for SAM during growth and development are achieved. Whether similar developmental changes occur in humans is unknown.
Non-alcoholic fatty liver disease establishment and progression: genetics and epigenetics as relevant modulators of the pathology
Published in Scandinavian Journal of Gastroenterology, 2023
Camila Cristiane Pansa, Letícia Ramos Molica, Karen C. M. Moraes
In NAFLD, the genetic profiling of advanced liver disease patients revealed that genes correlated to the 1 C metabolism reduced expression levels such of glycine N-methyltransferase (GNMT), betaine-homocysteine S methyltransferase (BHMT), cystathionine synthetase (CBS) and methionine adenosyltransferase (MAT1A) [118,119]. Moreover, other studies described that adenosylhomocysteinase (AHCY), MAT1A and methylenetetrahydrofolate dehydrogenase (MTHFD2) genes were hypermethylated, reducing SAM and changing global DNA methylation patterns and physiological problems [120]. To support those observations, methylome studies and transcriptome analysis correlated global hepatic DNA methylation with the progression of NAFLDs to more complex pathological conditions [93]. However, further studies are required to better understand the fine-tuning of DNA methylation and NAFLDs. In this context, the mechanistic characterization of elements that direct control epigenetic processes in NAFLD may be beneficial to developing innovative strategies in the treatment for hepatic steatosis treatment or even be used as a molecular marker in disease diagnostics [93,121].
High levels of blood glutamic acid and ornithine in children with intellectual disability
Published in International Journal of Developmental Disabilities, 2022
Muhammad Wasim, Haq Nawaz Khan, Hina Ayesha, Abdul Tawab, Fazal e Habib, Muhammad Rafique Asi, Mazhar Iqbal, Fazli Rabbi Awan
Among aminoacidopathies, phenylketonuria (PKU) is the most prevalent worldwide disorder (Wasim et al.2018a, 2018b, Brown and Lichter-Konecki 2016), but up till now from Pakistan, just a single report was recently published in which 18 patients have been described with high concentration of phenylalanine in their blood plasma, unfortunately, due to late diagnosis, all the patients already had developed irreversible intellectual disability (Ahmed et al.2019). Conversely, in the current study, not a single phenylketonuria (PKU) patient was identified, but interestingly, three intellectually disabled patients had high level of methionine (suspected for different disorders like homocystinuria (Cystathionine Beta synthase deficiency), Methionine adenosyltransferase I/III deficiency, Glycine N-Methyltransferase Deficiency, S-Adenosylhomocysteine hydrolase deficiency) (Nashabat et al.2018, Baric et al.2017, Baric et al.2005).
Quantitative analysis of sarcosine with special emphasis on biosensors: a review
Published in Biomarkers, 2019
C.S. Pundir, Ritu Deswal, Parveen Kumar
Sarcosine is synthesized by the glycine N-methyltransferase (GMT) and metabolized by sarcosine dehydrogenase (SARDH) enzyme (Heger et al.2016). An overview of sarcosine metabolism as well as various biological functions of sarcosine is represented in Figure 1. Sarcosine is present in a variety of food sources viz egg yolks, legumes, nuts, vegetables, turkey, ham, and other meats (Allen et al.1993). In the human body, it is present in skeletal muscles and prostate. Sarcosine represents an essential role in methyl donation, homeostasis and the one-carbon cycle. It is a major factor in nucleic acid synthesis. It accelerates the cell division and, therefore, helps in the growth and development of the foetus (Fasman and Blout 1963). Sarcosine has a distinct mild sweet flavour. An ingredient of toothpaste for decades, it prevents cavities and causes foaming. The increased levels of sarcosine have been implicated in pathophysiology of multiple diseases like Alzheimer, dementia, prostate cancer, colorectal cancer, stomach cancer, sarcosinemia, dimethylglycine dehydrogenase deficiency, eosinophilic esophagitis and Lewy body disease (Bar-Joseph et al.2012, Soliman et al.2012, Tsuruoka et al.2013). It is also a promising biomarker for prostate cancer. Research during past decades uncovered the clinical benefits of sarcosine in treating mental health disorders, including schizophrenia, depression, obsessive-compulsive disorder, seizures and stroke (Wu et al.2011). Serum sarcosine level is normally 80.8 ng/mL and 102.3 ng/mL in females and males respectively (Strzelecki et al.2015). Various physicochemical properties of sarcosine are summarized in Table 1.