Amino Acid Metabolism, Inborn Errors ; Humans ; Mitochondrial Diseases ; Sarcosine Dehydrogenase ; deficiency

INTRODUCTIONSarcosinaemia is a rare metabolic disorder which has not been reported in Asia.

CLINICAL PICTUREThe urine samples of 2 patients were screened as a routine metabolic screening offered for patients with mental retardation in our hospital. We used gas chromatography-mass spectrometry (GC-MS) which is capable of detecting abnormal pattern in amino acids and organic acids. Plasma sarcosine level was further quantified by GC-MS. The same methods were used in the investigations of asymptomatic family members. Urine examination by GC-MS revealed excessive amount of sarcosine in urine (normally undetectable) and their plasma sarcosine levels were raised. The 2 differential diagnoses of presence of sarcosine in urine--glutaric aciduria type II and folate deficiency--were ruled out by the absence of abnormal organic acids in the initial urine screen and by normal serum folate level respectively. Screening of the 2 families identified excessive sarcosine in urine in 2 siblings, one from each family. However, these 2 siblings of indexed patients thus identified have no neurological or developmental problem.

CONCLUSIONOur finding was consistent with the notion that sarcosinaemia is a benign condition picked up coincidentally during screening for mental retardation.

Amino Acid Metabolism, Inborn Errors ; complications ; diagnosis ; Child ; Child, Preschool ; China ; ethnology ; Family Health ; Female ; Gas Chromatography-Mass Spectrometry ; Hong Kong ; Humans ; India ; ethnology ; Intellectual Disability ; complications ; Sarcosine ; blood ; urine ; Sarcosine Dehydrogenase ; deficiency

Objective: This study aimed to investigate the effects of Methods: In this study, 0.1% DMG was supplemented in 20% casein diets that were either folate-sufficient (20C) or folate-deficient (20CFD). Blood and liver of rats were subjected to assays of Hcy and its metabolites. Hcy and its related metabolite concentrations were determined using a liquid chromatographic system. Results: Folate deprivation significantly increased pHcy concentration in rats fed 20C diet (from 14.19 ± 0.39 μmol/L to 28.49 ± 0.50 μmol/L; Conclusion DMG supplementation exhibited hypohomocysteinemic effects under folate-sufficient conditions. By contrast, the combination of folate deficiency and DMG supplementation has deleterious effect on pHcy concentration.
Animals ; Biomarkers/metabolism* ; Chromatography, Liquid ; Diet ; Dietary Supplements ; Folic Acid Deficiency/metabolism* ; Homocysteine/metabolism* ; Liver/metabolism* ; Male ; Random Allocation ; Rats ; Rats, Wistar ; Sarcosine/metabolism*

We purified a sarcosine oxidase from Bacillus sp. strain BSD-8 isolated from soil. We purified the enzyme by ammonium sulfate precipitation, DEAE-cellulose, Toyopearl hydrophobic and Sephadex G-75 molecular sieve chromatography and characterized the purified sarcosine oxidase. This sarcosine oxidase was a flavin enzyme containing a noncovalently bound flavin with the subunit molecular mass of 51 kDa. The optimal temperature for this enzyme was 60 degrees C and it showed its highest activity at pH 8.5. It was stable in the pH range of 8.0-10.0 and at the temperature of 60 degrees C. Estimated by Lineveaver-Burk plots, the K(m) of the enzyme was 3.1 mmol/L. Ag+, Hg2+, SDS and Tween 80 dramatically inhibted the enzyme activity, whereas Tween 20 and Triton X-100 had no effect on enzyme activity. The thermostability of this enzyme was better than reported sarcosine oxidases, and it could be applied in enzymatic measuring of creatinine.
Bacillus ; enzymology ; isolation & purification ; Bacterial Proteins ; chemistry ; isolation & purification ; metabolism ; Chemical Precipitation ; Enzyme Stability ; Sarcosine Oxidase ; chemistry ; isolation & purification ; metabolism ; Soil Microbiology

More and more studies have revealed that the level of serum prostate specific antigen(PSA) has little value for early diagnosis of prostate cancer (PCa). For example, negative prostate biopsies are as high as 70%-80% for patients with serum PSA ranging between 4 ng/mL and 10 ng/mL. However, the negative results cannot exclude the existence of cancer. In the studies of the early diagnosis of PCa, investigators focused on seeking biomarkers that have higher sensitivity and specificity. Recently, PSA derivatives, HPC1, PCA3, TMPRSS2: ETS, GSTP1, AMACR, GOLPH2, EPCA, sarcosine, and the combination of multiple biomarkers are widely discussed. In this article, we have reviewed their recent development and the prospective value of the combination of multiple biomarkers, which may be helpful for the early diagnosis and the prognostic monitoring of patients with PCa.
Antigens, Neoplasm ; metabolism ; Biomarkers, Tumor ; metabolism ; Early Diagnosis ; Endoribonucleases ; metabolism ; Glutathione S-Transferase pi ; metabolism ; Humans ; Male ; Membrane Proteins ; metabolism ; Oncogene Proteins, Fusion ; metabolism ; Prostate-Specific Antigen ; metabolism ; Prostatic Neoplasms ; diagnosis ; metabolism ; Racemases and Epimerases ; metabolism ; Sarcosine ; metabolism

PURPOSE: The aims of this study were to compare the expression of sarcosine metabolism-related proteins between invasive lobular carcinoma (ILC) and invasive ductal carcinoma (IDC) and to determine the implications of these results. MATERIALS AND METHODS: Tissue microarrays were constructed, containing 30 samples from normal breast tissue, 114 samples from patients with ILC, and 692 samples from patients with IDC. Immunohistochemical staining was performed to examine the expression of sarcosine metabolism-related proteins [glycine N-methyltransferase, sarcosine dehydrogenase, and l-pipecolic acid oxidase (PIPOX)]. RESULTS: The sarcosine metabolic phenotype differed between ILC and IDC (p<0.001). In IDC, sarcosine metabolic phenotype was distributed as null type (61.7%)>low sarcosine type (30.4%)>high sarcosine type (5.0%)>intermediate type (2.9%). However, in ILC, the sarcosine metabolic phenotype was distributed as low sarcosine type (61.4%)>null type (32.5%)>intermediate type (5.3%)>high sarcosine type (0.9%). PIPOX showed higher expression in ILC than in IDC (p<0.001) and correlated with androgen receptor (AR) positivity (p=0.001) in ILC. CONCLUSION: Expression of sarcosine metabolism-related proteins differed between ILC and IDC. Low sarcosine type was the majority sarcosine metabolic phenotype of ILC. PIPOX expression was predominant in ILC and correlated with AR positivity.
Adult ; Breast/pathology ; Breast Neoplasms/*metabolism/pathology ; Carcinoma, Ductal, Breast/*metabolism/pathology ; Carcinoma, Lobular/*metabolism ; Female ; Humans ; Immunohistochemistry ; Middle Aged ; Multivariate Analysis ; Phenotype ; Proportional Hazards Models ; Regression Analysis ; Retrospective Studies ; Sarcosine/genetics/*metabolism ; Tissue Array Analysis

Mutations in the fused in sarcoma/translocated in liposarcoma (FUS/TLS) gene have been associated with amyotrophic lateral sclerosis (ALS). FUS-positive neuropathology is reported in a range of neurodegenerative diseases, including ALS and fronto-temporal lobar degeneration with ubiquitin-positive pathology (FTLDU). To examine protein aggregation and cytotoxicity, we expressed human FUS protein in yeast. Expression of either wild type or ALS-associated R524S or P525L mutant FUS in yeast cells led to formation of aggregates and cytotoxicity, with the two ALS mutants showing increased cytotoxicity. Therefore, yeast cells expressing human FUS protein recapitulate key features of FUS-positive neurodegenerative diseases. Interestingly, a significant fraction of FUS expressing yeast cells stained by propidium iodide were without detectable protein aggregates, suggesting that membrane impairment and cellular damage caused by FUS expression may occur before protein aggregates become microscopically detectable and that aggregate formation might protect cells from FUS-mediated cytotoxicity. The N-terminus of FUS, containing the QGSY and G rich regions, is sufficient for the formation of aggregates but not cytotoxicity. The C-terminal domain, which contains a cluster of mutations, did not show aggregation or cytotoxicity. Similar to TDP-43 when expressed in yeast, FUS protein has the intrinsic property of forming aggregates in the absence of other human proteins. On the other hand, the aggregates formed by FUS are thioflavin T-positive and resistant to 0.5% sarkosyl, unlike TDP-43 when expressed in yeast cells. Furthermore, TDP-43 and FUS display distinct domain requirements in aggregate formation and cytotoxicity.
Amino Acid Sequence ; Amino Acid Substitution ; DNA-Binding Proteins ; genetics ; metabolism ; Humans ; Mutation ; Neurodegenerative Diseases ; pathology ; Protein Structure, Tertiary ; RNA-Binding Protein FUS ; chemistry ; genetics ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; toxicity ; Saccharomyces cerevisiae ; growth & development ; metabolism ; Sarcosine ; analogs & derivatives ; pharmacology ; Thiazoles ; metabolism