Efficacy of nutrition therapy with food rich in methionine for treating nonalcoholic fatty liver / Eficacia de la terapia nutricional con alimentos ricos en metionina para el tratamiento de hígado graso no alcohólico

Non-Alcoholic Fatty Liver disease (NAFLD) can lead to Non Alcoholic steatohepatitis (NASH), cirrhosis, and liver cancer. The treatment for NAFLD involves modification of caloric intake and physical activity. NAFLD has a pro-oxidant nature; therefore, it is logical to suppose that the antioxidant methionine can be used as a treatment for this disease. Aim. This study aimed to evaluate the effect of high-methionine dietary therapy on patients with NAFLD. Materials and methods. A randomized clinical study was conducted over three months. In this study, 121 NAFLD patients participated, and the age of the participants was ≥ 20 years (experimental group included 56 and control group 65), all of whom were randomized and matched by sex, recluted from the ISSSTE hospital in Xalapa, Mexico. The patients were instructed to consume food to cover the recommended methionine daily doses, and the daily amount consumed was calculated. Methionine effect was measured as NAFLD regression and quality of life improvement. Results. Nutritional therapy induced NAFLD regression and diminished central fat accumulation, blood pressure, and the fatty liver index. Some parameters, such as liver enzymes, did not changed. The quality of life of patients improved after treatment. Conclusions. In this study, we show a hepatoprotective effect induced only in three months of chances in the diet, thus, a longer diet may generate more relevant benefits in the resistant parameters of our study(AU)

La enfermedad del hígado graso no alcohólico (NAFLD) puede conducir a la esteatohepatitis no alcohólica (NASH), la cirrosis y el cáncer de hígado. El tratamiento para NAFLD es la modificación de la ingesta calórica y la actividad física. Debido a que NAFLD tiene una naturaleza pro-oxidante; es lógico suponer que el antioxidante metionina puede utilizarse en el tratamiento de esta enfermedad. Objetivo. el presente trabajo evaluó el papel de la terapia nutricional con alimentos ricos en metioninaen pacientes con NAFLD. Materiales y Métodos. Se realizó un ensayo clínico aleatorizado durante tres meses. Participaron en el estudio 121 pacientes con NAFLD con edad ≥ 20 años (56 en el grupo experimental y 65 en el control), todos aleatorizados y pareados por sexo, reclutados de la Clínica Hospital ISSTE en la ciudad de Xalapa, México, en el año 2015. Se instruyó a los pacientes en consumir los alimentos hasta completar la dosis diaria recomendada de metioninay se calculó la cantidad diaria consumida. Su efecto se midió como la regresión de NAFLD y la mejora de la calidad de vida. Resultados. La terapia nutricional retrocedió NAFLD; disminuyó la acumulación de grasa central, la presión arterial y el índice de hígado graso. Algunos parámetros, como las enzimas de la función hepática, no se modificaron con el tratamiento. Otro parámetro fue la mejora de la calidad de vida de los pacientes tratados. Conclusiones. En este trabajo mostramos un impacto hepatoprotector producido con tan solo tres meses de cambios en la dieta, por lo que una dieta más prolongada podría generar beneficios aún más significativos en los parámetros resistentes en nuestro protocolo(AU)

Effects of Methionine Restriction on Proliferation, Cell Cycle, and Apoptosis of Human Acute Leukemia Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of methionine restriction on proliferation, cell cycle and apoptosis of human acute leukemia cells.@*METHODS@#Cell Counting Kit-8 (CCK-8) assay was used to detect the effect of methionine restriction on HL-60 and Jurkat cells proliferation. The effect of methionine restriction on cell cycle of HL-60 and Jurkat cells was examined by PI staining. Annexin V-FITC / PI double staining was applied to detect apoptosis of HL-60 and Jurkat cells following methionine restriction. The expression of cell cycle-related proteins cyclin B1, CDC2 and apoptosis-related protein Bcl-2 was evaluated by Western blot assay.@*RESULTS@#Methionine restriction significantly inhibited the proliferation of HL-60 and Jurkat cells in a time-dependent manner (HL-60: r =0.7773, Jurkat: r =0.8725), arrested the cells at G2/M phase (P < 0.001), and significantly induced apoptosis of HL-60 and Jurkat cells (HL-60: P < 0.001; Jurkat: P < 0.05). Furthermore, Western blot analysis demonstrated that methionine restriction significantly reduced the proteins expression of Cyclin B1 (P < 0.05), CDC2 (P < 0.01) and Bcl-2 (P < 0.001) in HL-60 and Jurkat cells.@*CONCLUSION@#Acute leukemia cells HL-60 and Jurkat exhibit methionine dependence. Methionine restriction can significantly inhibit the proliferation, promote cell cycle arrest and induce apoptosis of HL-60 and Jurkat cells, which suggests that methionine restriction may be a potential therapeutic strategy for acute leukemia.

Synthesis and application of the methyl analogues of S-adenosyl-L-methionine / 生物工程学报

Methylation plays a vital role in biological systems. SAM (S-adenosyl-L-methionine), an abundant cofactor in life, acts as a methyl donor in most biological methylation reactions. SAM-dependent methyltransferases (MTase) transfer a methyl group from SAM to substrates, thereby altering their physicochemical properties or biological activities. In recent years, many SAM analogues with alternative methyl substituents have been synthesized and applied to methyltransferases that specifically transfer different groups to the substrates. These include functional groups for labeling experiments and novel alkyl modifications. This review summarizes the recent progress in the synthesis and application of SAM methyl analogues and prospects for future research directions in this field.

Efficient synthesis of L-methionine by engineering the one carbon module of Escherichia coli / 生物工程学报

L-methionine, also known as L-aminomethane, is one of the eight essential amino acids required by the human body and has important applications in the fields of feed, medicine, and food. In this study, an L-methionine high-yielding strain was constructed using a modular metabolic engineering strategy based on the M2 strain (Escherichia coli W3110 ΔIJAHFEBC/PAM) previously constructed in our laboratory. Firstly, the production of one-carbon module methyl donors was enhanced by overexpression of methylenetetrahydrofolate reductase (methylenetetrahydrofolate reductase, MetF) and screening of hydroxymethyltransferase (GlyA) from different sources, optimizing the one-carbon module. Subsequently, cysteamine lyase (hydroxymethyltransferase, MalY) and cysteine internal transporter gene (fliY) were overexpressed to improve the supply of L-homocysteine and L-cysteine, two precursors of the one-carbon module. The production of L-methionine in shake flask fermentation was increased from 2.8 g/L to 4.05 g/L, and up to 18.26 g/L in a 5 L fermenter. The results indicate that the one carbon module has a significant impact on the biosynthesis of L-methionine, and efficient biosynthesis of L-methionine can be achieved through optimizing the one carbon module. This study may facilitate further improvement of microbial fermentation production of L-methionine.

Microbial production of S-adenosyl-l-methionine: a review / 生物工程学报

S-adenosyl-l-methionine (SAM) is ubiquitous in living organisms and plays important roles in transmethylation, transsulfuration and transamination in organisms. Due to its important physiological functions, production of SAM has attracted increasing attentions. Currently, researches on SAM production mainly focus on microbial fermentation, which is more cost-effective than that of the chemical synthesis and the enzyme catalysis, thus easier to achieve commercial production. With the rapid growth in SAM demand, interests in improving SAM production by developing SAM hyper-producing microorganisms aroused. The main strategies for improving SAM productivity of microorganisms include conventional breeding and metabolic engineering. This review summarizes the recent research progress in improving microbial SAM productivity to facilitate further improving SAM productivity. The bottlenecks in SAM biosynthesis and the solutions were also addressed.

Comparative analysis of various sources of selenium on the growth performance and antioxidant status in broilers under heat stress / Análise comparativa de várias fontes de selênio no desempenho de crescimento e status antioxidante em frangos de corte sob estresse térmico

The supplementation of Selenium-enriched probiotics is effective in reducing oxidative stress and maintaining meat quality stability in broiler chicken especially under heat stress. An experimental study was conducted to perform Comparative analysis of Selenium yeast with inorganic Se in broilers under heat stress. A total of 120 broilers chicks of one day were assigned to 4 groups each consisting 30 chicks fed on same basal diet but different selenium sources. The basal diet of group D1 was not supplemented with Se source (Negative control), group D2 basal diet was supplemented with inorganic selenium (Sodium selenite 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase), group D3 basal diet was supplemented with commercially available organic selenium (Seleno-methionine 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase) and group D4 basal diet was supplemented with self-developed organic selenium (Se-enriched yeast 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase). The performance parameters i.e. feed intake (FI), live body weight (BW) and FCR were not significantly (p>0.05) effected by selenium supplementation in the starter phase but were significantly (p<0.05) effected in the finisher phase. Selenium supplementation significantly (p<0.05) effected serum Se level in different supplemented groups. Higher serum Se value (58.20±0.06) was recorded in D4 group. Similarly significantly lower selenium value was recorded for D4 and higher was recorded for D1 (11.36±0.08). However lower serum Paraoxonase (PON) value was recorded for D4 (13.24±0.01) and higher for D1 (13.33±0.03). Comparatively self-developed Se enriched yeast increased the Se accumulation and improved antioxidant system. Glutathione peroxidase (GPx) was found higher in D4 (12.333±0.03) followed by D3, D2 and D1 respectively. Whereas superoxide dismutase (SOD) was significantly lower (p<0.05) in D4 (0.1437±0.003) followed by D3 (0.1457±0.002). Selenium supplementation increased the [...].

A suplementação de probióticos enriquecidos com selênio é eficaz na redução do estresse oxidativo e na manutenção da estabilidade da qualidade da carne em frangos de corte, especialmente sob estresse por calor. Um estudo experimental foi conduzido para realizar uma análise comparativa da levedura selênio com o Se inorgânico em frangos de corte sob estresse térmico. Um total de 120 pintos de um dia foi dividido em 4 grupos, cada um consistindo de 30 pintos alimentados com a mesma dieta basal, mas com diferentes fontes de selênio. A dieta basal do grupo D1 não foi suplementada com fonte de Se (controle negativo), a dieta basal do grupo D2 foi suplementada com selênio inorgânico (selenito de sódio 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora), a dieta basal do grupo D3 foi suplementada com selênio orgânico disponível comercialmente (fase inicial de seleno-metionina 0,22 mg / kg e fase finalizadora de 0,15 mg / kg) e a dieta basal do grupo D4 foi suplementada com selênio orgânico autodesenvolvido (fermento enriquecido com Se 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora). Os parâmetros de desempenho, ou seja, consumo de ração (FI), peso corporal vivo (PC) e FCR não foram significativamente (p > 0,05) afetados pela suplementação de selênio na fase inicial, mas foram significativamente (p < 0,05) afetados na fase final. A suplementação de selênio afetou significativamente (p < 0,05) o nível de Se sérico em diferentes grupos suplementados. O maior valor de Se sérico (58,20 ± 0,06) foi registrado no grupo D4. Da mesma forma, valor de selênio significativamente menor foi registrado para D4 e maior foi registrado para D1 (11,36 ± 0,08). No entanto, um valor mais baixo de Paraoxonase (PON) sérica foi registrado para D4 (13,24 ± 0,01) e mais alto para D1 (13,33 ± 0,03). A levedura enriquecida com Se comparativamente autodesenvolvida aumentou o acúmulo de Se e melhorou o sistema [...].

Comparative analysis of various sources of selenium on the growth performance and antioxidant status in broilers under heat stress

Abstract The supplementation of Selenium-enriched probiotics is effective in reducing oxidative stress and maintaining meat quality stability in broiler chicken especially under heat stress. An experimental study was conducted to perform Comparative analysis of Selenium yeast with inorganic Se in broilers under heat stress. A total of 120 broilers chicks of one day were assigned to 4 groups each consisting 30 chicks fed on same basal diet but different selenium sources. The basal diet of group D1 was not supplemented with Se source (Negative control), group D2 basal diet was supplemented with inorganic selenium (Sodium selenite 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase), group D3 basal diet was supplemented with commercially available organic selenium (Seleno-methionine 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase) and group D4 basal diet was supplemented with self-developed organic selenium (Se-enriched yeast 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase). The performance parameters i.e. feed intake (FI), live body weight (BW) and FCR were not significantly (p>0.05) effected by selenium supplementation in the starter phase but were significantly (p 0.05) effected in the finisher phase. Selenium supplementation significantly (p 0.05) effected serum Se level in different supplemented groups. Higher serum Se value (58.20±0.06) was recorded in D4 group. Similarly significantly lower selenium value was recorded for D4 and higher was recorded for D1 (11.36±0.08). However lower serum Paraoxonase (PON) value was recorded for D4 (13.24±0.01) and higher for D1 (13.33±0.03). Comparatively self-developed Se enriched yeast increased the Se accumulation and improved antioxidant system. Glutathione peroxidase (GPx) was found higher in D4 (12.333±0.03) followed by D3, D2 and D1 respectively. Whereas superoxide dismutase (SOD) was significantly lower (p 0.05) in D4 (0.1437±0.003) followed by D3 (0.1457±0.002). Selenium supplementation increased the birds survival rate. Birds fed on Se enriched yeast showed higher Se deposition and better antioxidant capacity as compared to other sources of selenium. Se-enriched yeast displayed an improved result on Se deposition in tissues, and oxidative capacity, meat tenderness and immune response level as compared to other sources of selenium.

Resumo A suplementação de probióticos enriquecidos com selênio é eficaz na redução do estresse oxidativo e na manutenção da estabilidade da qualidade da carne em frangos de corte, especialmente sob estresse por calor. Um estudo experimental foi conduzido para realizar uma análise comparativa da levedura selênio com o Se inorgânico em frangos de corte sob estresse térmico. Um total de 120 pintos de um dia foi dividido em 4 grupos, cada um consistindo de 30 pintos alimentados com a mesma dieta basal, mas com diferentes fontes de selênio. A dieta basal do grupo D1 não foi suplementada com fonte de Se (controle negativo), a dieta basal do grupo D2 foi suplementada com selênio inorgânico (selenito de sódio 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora), a dieta basal do grupo D3 foi suplementada com selênio orgânico disponível comercialmente (fase inicial de seleno-metionina 0,22 mg / kg e fase finalizadora de 0,15 mg / kg) e a dieta basal do grupo D4 foi suplementada com selênio orgânico autodesenvolvido (fermento enriquecido com Se 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora). Os parâmetros de desempenho, ou seja, consumo de ração (FI), peso corporal vivo (PC) e FCR não foram significativamente (p > 0,05) afetados pela suplementação de selênio na fase inicial, mas foram significativamente (p 0,05) afetados na fase final. A suplementação de selênio afetou significativamente (p 0,05) o nível de Se sérico em diferentes grupos suplementados. O maior valor de Se sérico (58,20 ± 0,06) foi registrado no grupo D4. Da mesma forma, valor de selênio significativamente menor foi registrado para D4 e maior foi registrado para D1 (11,36 ± 0,08). No entanto, um valor mais baixo de Paraoxonase (PON) sérica foi registrado para D4 (13,24 ± 0,01) e mais alto para D1 (13,33 ± 0,03). A levedura enriquecida com Se comparativamente autodesenvolvida aumentou o acúmulo de Se e melhorou o sistema antioxidante. A glutationa peroxidase (GPx) foi encontrada maior em D4 (12,333 ± 0,03) seguido por D3, D2 e D1 respectivamente. Enquanto a superóxido dismutase (SOD) foi significativamente menor (p 0,05) em D4 (0,1437 ± 0,003) seguido por D3 (0,1457 ± 0,002). A suplementação de selênio aumentou a taxa de sobrevivência da ave. Aves alimentadas com levedura enriquecida com Se apresentaram maior deposição de Se e melhor capacidade antioxidante em comparação com outras fontes de selênio. A levedura enriquecida com Se apresentou um resultado melhorado na deposição de Se nos tecidos, capacidade oxidativa, maciez da carne e nível de resposta imune em comparação com outras fontes de selênio.

Comparative analysis of various sources of selenium on the growth performance and antioxidant status in broilers under heat stress / Análise comparativa de várias fontes de selênio no desempenho de crescimento e status antioxidante em frangos de corte sob estresse térmico

Abstract The supplementation of Selenium-enriched probiotics is effective in reducing oxidative stress and maintaining meat quality stability in broiler chicken especially under heat stress. An experimental study was conducted to perform Comparative analysis of Selenium yeast with inorganic Se in broilers under heat stress. A total of 120 broilers chicks of one day were assigned to 4 groups each consisting 30 chicks fed on same basal diet but different selenium sources. The basal diet of group D1 was not supplemented with Se source (Negative control), group D2 basal diet was supplemented with inorganic selenium (Sodium selenite 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase), group D3 basal diet was supplemented with commercially available organic selenium (Seleno-methionine 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase) and group D4 basal diet was supplemented with self-developed organic selenium (Se-enriched yeast 0.22mg/Kg starter phase and 0.15mg/Kg finisher phase). The performance parameters i.e. feed intake (FI), live body weight (BW) and FCR were not significantly (p>0.05) effected by selenium supplementation in the starter phase but were significantly (p<0.05) effected in the finisher phase. Selenium supplementation significantly (p<0.05) effected serum Se level in different supplemented groups. Higher serum Se value (58.20±0.06) was recorded in D4 group. Similarly significantly lower selenium value was recorded for D4 and higher was recorded for D1 (11.36±0.08). However lower serum Paraoxonase (PON) value was recorded for D4 (13.24±0.01) and higher for D1 (13.33±0.03). Comparatively self-developed Se enriched yeast increased the Se accumulation and improved antioxidant system. Glutathione peroxidase (GPx) was found higher in D4 (12.333±0.03) followed by D3, D2 and D1 respectively. Whereas superoxide dismutase (SOD) was significantly lower (p<0.05) in D4 (0.1437±0.003) followed by D3 (0.1457±0.002). Selenium supplementation increased the bird's survival rate. Birds fed on Se enriched yeast showed higher Se deposition and better antioxidant capacity as compared to other sources of selenium. Se-enriched yeast displayed an improved result on Se deposition in tissues, and oxidative capacity, meat tenderness and immune response level as compared to other sources of selenium.

Resumo A suplementação de probióticos enriquecidos com selênio é eficaz na redução do estresse oxidativo e na manutenção da estabilidade da qualidade da carne em frangos de corte, especialmente sob estresse por calor. Um estudo experimental foi conduzido para realizar uma análise comparativa da levedura selênio com o Se inorgânico em frangos de corte sob estresse térmico. Um total de 120 pintos de um dia foi dividido em 4 grupos, cada um consistindo de 30 pintos alimentados com a mesma dieta basal, mas com diferentes fontes de selênio. A dieta basal do grupo D1 não foi suplementada com fonte de Se (controle negativo), a dieta basal do grupo D2 foi suplementada com selênio inorgânico (selenito de sódio 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora), a dieta basal do grupo D3 foi suplementada com selênio orgânico disponível comercialmente (fase inicial de seleno-metionina 0,22 mg / kg e fase finalizadora de 0,15 mg / kg) e a dieta basal do grupo D4 foi suplementada com selênio orgânico autodesenvolvido (fermento enriquecido com Se 0,22 mg / kg fase inicial e 0,15 mg / kg fase finalizadora). Os parâmetros de desempenho, ou seja, consumo de ração (FI), peso corporal vivo (PC) e FCR não foram significativamente (p > 0,05) afetados pela suplementação de selênio na fase inicial, mas foram significativamente (p < 0,05) afetados na fase final. A suplementação de selênio afetou significativamente (p < 0,05) o nível de Se sérico em diferentes grupos suplementados. O maior valor de Se sérico (58,20 ± 0,06) foi registrado no grupo D4. Da mesma forma, valor de selênio significativamente menor foi registrado para D4 e maior foi registrado para D1 (11,36 ± 0,08). No entanto, um valor mais baixo de Paraoxonase (PON) sérica foi registrado para D4 (13,24 ± 0,01) e mais alto para D1 (13,33 ± 0,03). A levedura enriquecida com Se comparativamente autodesenvolvida aumentou o acúmulo de Se e melhorou o sistema antioxidante. A glutationa peroxidase (GPx) foi encontrada maior em D4 (12,333 ± 0,03) seguido por D3, D2 e ​​D1 respectivamente. Enquanto a superóxido dismutase (SOD) foi significativamente menor (p < 0,05) em D4 (0,1437 ± 0,003) seguido por D3 (0,1457 ± 0,002). A suplementação de selênio aumentou a taxa de sobrevivência da ave. Aves alimentadas com levedura enriquecida com Se apresentaram maior deposição de Se e melhor capacidade antioxidante em comparação com outras fontes de selênio. A levedura enriquecida com Se apresentou um resultado melhorado na deposição de Se nos tecidos, capacidade oxidativa, maciez da carne e nível de resposta imune em comparação com outras fontes de selênio.

A case of interstitial lung and liver disease caused by MARS1 gene mutation / 中国当代儿科杂志

The patient is a female infant, 4 months and 9 days old, who was admitted to the hospital due to recurrent fever, cough, and hepatomegaly for over a month. The patient was a healthy full-term infant with a normal birth history. At 2 months and 22 days after birth, she developed recurrent fever, cough, and respiratory distress. Chest imaging revealed diffuse bilateral lung lesions, and fiberoptic bronchoscopy showed interstitial changes in both lungs. These suggested the presence of interstitial lung disease. The patient also presented with hepatomegaly, anemia, hyperlipidemia, hypothyroidism, and malnutrition. Genetic testing indicated compound heterozygous variations in the MARS1 gene. This mutation can cause interstitial lung and liver disease, which is a severe rare disorder that typically manifests in infancy or early childhood. It is inherited in an autosomal recessive manner and characterized by early-onset respiratory insufficiency and liver disease in infants or young children. Since its first reported case in 2013, as of June 2023, only 38 related cases have been reported worldwide. This article reports the multidisciplinary diagnosis and treatment of interstitial lung and liver disease in an infant caused by MARS1 gene mutation.

The Effect of Dietary Supplement on Glutathione Level in Rats

Background: Oxidative stress occurs due to decreased glutathione inside the body. Some supplements may promote and stimulate glutathione production in the liver. This article aims to investigate the impact of different supplements on enhancing glutathione synthesis in rats’ livers. For this purpose 42 rats (male albino) were separated into 7 groups, each including 6 animals with average weights ranging between 150 and 160 g. Group 1 (control) and different groups consumed a basal diet for 8 weeks, whereas group 2 received 500 mg/kg bw of L-cysteine daily. Group 3 received 250 mg/kg bw of methionine, while group 4 got 250 mg/kg of L cysteine plus 125 mg/kg of methionine daily. Spirulina (20 mg/kg bw), turmeric (500 mg/kg bw), and dried garlic (500 mg/kg bw), respectively, were given to groups 5, 6, and 7. Results: Utilizing the various dietary supplements decreased levels of liver function enzymes, bilirubin, urea, creatinine, and malondialdehyde while enhancing levels antioxidant enzymes of liver, and increased glutathione of kidneys and liver. However, cysteine alone at 500 mg/kg bw decreased glutathione formation in the liver and kidneys. Compared to the amino acid supplements (group 2, 3, 4) used, spirulina, turmeric, and dried garlic had a significant impact on reducing liver function enzymes, bilirubin, uric acid, creatinine, urea, and malondialdehyde and increasing antioxidant enzymes, and glutathione while turmeric supplement showed the best influence. Using dietary supplements did not result in any pathological modifications in the liver tissues, but there were some unsatisfactory minor alterations. However, group 2 showed considerable pathological developments in the liver tissues. Conclusion: According to the findings, using the suggested dietary supplement except for cysteine alone can promote and encourage glutathione synthesis in different organs, especially the liver, hence alleviating the effects of oxidative stress associated with several illnesses.

Assessment of MTR Rs1805087 SNP as Possible Modifier ofSickle Cell Disease Severity in a Nigerian Population

BACKGROUND: Sickle cell disease is the commonest geneticdisorder in Nigeria, affecting 2­3% of an estimated population of 160million people. The role of genetic mutations in folate cycle genes,and the variable phenotypic expressions constituting disease severity,needs to be critically examined.OBJECTIVE: This study was carried out to establish the pattern ofmethionine synthase gene mutations (rs1805087 SNP), and its possibleassociation with disease severity in adults with sickle cell anaemia inLagos, Nigeria.METHODOLOGY: This is a cross-sectional study of seventy (70)subjects with sickle cell disease (HbSS) matched for age and genderwith known apparently healthy haemoglobin genotype AA (HbAA)subjects, as cases and controls respectively. Structured questionnaireswere used to obtain demographic, clinical and other phenotypic dataneeded to compute disease severity. Pattern of MTR A2756G genemutation and homocysteine assay (Hcy) were assessed by PolymeraseCh ain Reaction and Enzyme- linked Immun osorbent Assayrespectively. Full blood count analysis of participants was done usingthe KX-21 Automated Analyzer (Sysmex Corporation, Japan).RESULTS: The mutant genotypes MTR 2756 AG/GG were recordedin 46.4% (n =55) of subjects with disease severity score >7. Elevatedplasma homocysteine (HHcy) was significantly associated withdisease severity among HbSS subjects (OR=17.2, CI: 3.490-86.079;p=0.0001). Conversely, no significant association was observed withthe mutant genotypes MTR 2756 AG/GG and disease severity(p>0.05).CONCLUSION: While HHcy is significantly associated withphenotypic expression of HbSS, the MTR 2756 SNPs did not appearto independently influence homocysteine level or disease severity inHbSS subjects

Involvement of Opioid Peptides in the Analgesic Effect of Spinal Cord Stimulation in a Rat Model of Neuropathic Pain / 神经科学通报·英文版

Spinal cord stimulation (SCS)-induced analgesia was characterized, and its underlying mechanisms were examined in a spared nerve injury model of neuropathic pain in rats. The analgesic effect of SCS with moderate mechanical hypersensitivity was increased with increasing stimulation intensity between the 20% and 80% motor thresholds. Various frequencies (2, 15, 50, 100, 10000 Hz, and 2/100 Hz dense-dispersed) of SCS were similarly effective. SCS-induced analgesia was maintained without tolerance within 24 h of continuous stimulation. SCS at 2 Hz significantly increased methionine enkephalin content in the cerebrospinal fluid. The analgesic effect of 2 Hz was abolished by μ or κ opioid receptor antagonist. The effect of 100 Hz was prevented by a κ antagonist, and that of 10 kHz was blocked by any of the μ, δ, or κ receptor antagonists, suggesting that the analgesic effect of SCS at different frequencies is mediated by different endorphins and opioid receptors.

Methionine Metabolism and Related Gene Expression Regulation in Cancers / 中国生物化学与分子生物学报

Methionine, an essential amino acid with a variety of physiological functions, plays an important role in the process of metabolic reprogramming of cancer cells. A large number of studies have found that there is dependence on exogenous methionine in different kinds of cancer cells, which is called the Hoffman effect. In vivo, methionine is metabolized through the methionine cycle, linking with the one carbon unit metabolism, folate cycle and the synthesis of many substances such as polyamine, glutathione, cysteine and nucleotide. Abnormity of methionine metabolism often occurs in tumors, accompanied by abnormal gene expression of methionine metabolism related enzymes, including methionine adenosyltransferase (MAT) and methylthioadenosine phosphorylase (MTAP). The abnormal expression of MAT and MTAP can lead to the abnormity of methionine cycle and the salvage pathway, resulting in the decrease of methyl donor S⁃adenosylmethionine (SAM) and the accumulation of methylthioadenosine (MTA) in cancer cells, which is associated with the genesis, progression and metastasis of tumors. Methionine restriction and target therapy derive from the changes of methionine metabolism and related gene expression separately. This review summarizes the changes of methionine⁃ dependent metabolism and the expression regulation of methionine metabolism related genes in cancer cells. Also, the new progress and difficulty in methionine⁃related cancer therapy is introduced. This review may provide new clues for the exploration of cancer therapy.

D-methionine eradicates Porphyromonas gingivalis biofilms by suppressing the cyclic di-GMP level / 口腔疾病防治

Objective@#To investigate the mechanisms by which D-methionine (D-Met) eradicates Porphyromonas gingivalis biofilms by suppressing cyclic dimeric GMP (c-di-GMP) levels.@*Methods @#Cell viability, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured to determine the effective concentrations of D-Met, which were subsequently used in the following experiments. During the P. gingivalis biofilm formation inhibition experiment and the mature biofilm disassembly experiment, biofilm biomass, exopolysaccharide (EPS), biofilm morphology, integrity of the cell membrane, and the level of c-di-GMP were determined. @*Results @# D-Met < 40 mmol/L was biocompatible. During the biofilm formation inhibition and mature biofilm disassembly experiments, D-Met ≥ 20 mmol/L decreased the biofilm biomass and the production of EPS. SEM analysis showed that the extracellular matrix and bacterial density were drastically reduced by D-Met ≥ 20 mmol/L. TEM detection showed that 35 mmol/L D-Met ruptured the cell membrane during biofilm formation and increased the permeability of the cell membrane in the disassembly phase of mature biofilms. C-di-GMP levels decreased with increasing concentrations of D-Met in a concentration-dependent manner.@* Conclusion @# D-Met ≥ 20 mmol/L could eradicate P. gingivalis biofilms by suppressing c-di-GMP levels.

Mechanism of Tibetan medicine Ershiwuwei Songshi Pills in regulating intestinal flora and improving non-alcoholic steatohepatitis / 中国中药杂志

This study aimed to investigate the effect of Tibetan medicine Ershiwuwei Songshi Pills(ESP) on the intestinal flora of non-alcoholic steatohepatitis(NASH) mice. Forty-eight male C57 BL/6 mice were randomly divided into the control group, model(methionine-choline-deficient, MCD) group, high-(0.8 g·kg~(-1)), medium-(0.4 g·kg~(-1)), and low-dose(0.2 g·kg~(-1)) ESP groups, and pioglitazone(PGZ, 10 mg·kg~(-1)) group, with eight mice in each group. Mice in the control group were fed with normal diet, while those in the remaining five groups with MCD diet for five weeks for inducing NASH. During modeling, they were gavaged with the corresponding drugs. The changes in body mass, daily water intake, and daily food intake were recorded. At the end of the experiment, the liver tissues were collected and stained with hematoxylin-eosin(HE) for observing the pathological changes, followed by oil red O staining for observing fat accumulation in the liver. The levels of serum aspartate aminotransferase(AST) and alanine aminotransferase(ALT) and triglyceride(TG) in liver tissue were measured. The changes in intestinal flora of mice were determined using 16 S rRNA high-throughput sequencing technology. The results showed that compared with the model group, the high-, medium-and low-dose ESP groups and the PGZ group exhibited significantly lowered AST and ALT in serum and TG in liver tissues and alleviated hepatocellular steatosis and fat accumulation in the liver. As demonstrated by 16 S rRNA sequencing, the abundance index and diversity of intestinal flora decreased in the model group, while those increased in the ESP groups. Besides, the Firmicutes to Bacteroidetes ratio decreased at the phylum level. In the alteration of the composition of intestinal flora, ESP reduced the abundance of Erysipelotrichia and Faecalibaculum but increased the abundance of Desulfovibrionaceae, Rikenellaceae, Lachnospiraceae, and Ruminococcaceae. This study has revealed that ESP has a protective effect against NASH induced by MCD diet, which may be related to its regulation of the changes in intestinal flora, alteration of the composition of intestinal flora, and inhibition of the intestinal dysbiosis.

Identification and functional analysis of combined oxidative phosphorylation deficiency 28 gene mutation / 中华内科杂志

Objective:To report a case of combined oxidative phosphorylation deficiency 28 (COXPD28) in China, identified the pathogenic mutation and explored the pathogenic mechanism preliminarily.Methods:The clinical characteristics of a patient with COXPD28 were retrospectively analyzed and the pathogenic mutations were identified by mitochondrial gene sequencing and whole exome sequencing. The wild-type and mutant plasmids of pathogenic genes were constructed, and effect of mutation on protein expression by quantitative real-time PCR (qPCR) and Western blot were evaluated. Statistical methods mainly used one-way ANOVA and LSD test.Results:A 21 year old female patient presented with lactic acid poisoning due to repeated chest distress and wheezing since childhood. The sequencing of the whole exon group gene found that solute carrier family 25 member 26 (SLC25A26) gene had a compound heterozygous mutation (c.34G>C, p.A12P; c.197C>A, p.A66E), which was the first report in China. In vitro function test showed that the expression levels of SLC25A26 mRNA and S-adenosylmethionine carrier (SAMC) protein in cells transfected with SLC25A26 mutant plasmid were significantly lower than those transfected with wild type plasmid. The p.A66E mutant plasmid reduced the expression level of SLC25A26 mRNA and SAMC protein to 6% and 26% of wild type plasmids respectively (both P<0.001), while p.A12P mutant plasmid decreased to 62% and 82% of wild type plasmids respectively ( P<0.001, P=0.044). When the double mutant (p.A66E+p.A12P) plasmids were co-transfected, the expression levels of SLC25A26 mRNA and SAMC protein decreased to 47% and 57% of the wild type plasmids, respectively ( P<0.001, P=0.001). Conclusion:The pathogenic mutation gene of this patient with COXPD28 is SLC25A26 gene mutation (p.A66E, p.A12P), which causes the decrease of SLC25A26 expression level, mitochondrial oxidative phosphorylation dysfunction, and induces COXPD28.

Oxidized related substance of methionine in compound amino acid injection (18AA-Ⅱ) / 中国药科大学学报

@#TA method for the content determination of methionine sulfoxide and methionine sulfone in compound amino acid injection (18AA-II) was established in order to investigate their level in 155 batches of this product, and to explore the reason for the generation of these two impurities.The determination was performed on an Agilent Poroshell 120 EC-C18 column with mobile phases of sodium acetate/tetrahydrofuran solution (A) and sodium acetate solution -acetonitrile-methanol (B, 200∶400∶400) (gradient elution) at the flow rate of 0.5 mL/min.The excitation wavelength and the emission wavelength of the fluorescence detector were 233 nm and 441 nm, respectively.The column temperature was 40 °C, and the injection volume was 8 μL.The contents of methionine sulfoxide and methionine sulfone from 155 batches of compound amino acid injection (18AA-II) was determined using this method, and the residual oxygen content was detected by headspace gas analyzer.The results showed that the linear range of methionine sulfoxide and methionine sulfone were 0.128 1-10.250 0 μg/mL (r = 0.999 9) and 0.261 0-10.440 0 μg/mL (r = 0.999 8), respectively.The limits of quantitation were 0.13 μg/mL and 0.26 μg/mL, respectively; the limits of detection were 0.04 μg/mL and 0.09 μg/mL, respectively.RSDs of precision, stability and repetitive test were all lower than 1.3%.The recoveries ranged 98.00%-100.79% (RSD = 1.15%, n = 9) and 98.19%-102.31% (RSD = 1.33%, n = 9).The content level of oxidized related substances from different manufacturers showed significant difference, showing relevance with the residual oxygen content to some extent, yet no significant correlation with the added amount of antioxygen (sodium pyrosulfite).The method is validated to be useful for the content control of methionine sulfoxide and methionine sulfone in compound amino acid injection (18AA-II).It is quite necessary to include the determination of oxidized related substance into the quality specification.Manufacturers should strengthen the control of remaining oxygen in their products.

Distribution of gene polymorphism in folate metabolism pathway and its effect on serumhomocysteine concentration / 中国临床药理学与治疗学

AIM: To study the polymorphism distribution of methylenetetrahydrofolate reductase (MTHFR) and methionine synthase reductase (MTRR) genes and their influence on serum homocysteine (Hcy) concentration. METHODS: A total of 148 patients diagnosed with ischemic stroke from November 2020 to February 2021 in Yijishan Hospital of Wanan Medical College were selected for the study, and patients were typed for MTHFR 677C/T and MTRR 66A/G genes using fluorescent staining in situ hybridization technique. Serum Hcy concentrations were measured in 21 patients using a circulating enzyme assay. The distribution of MTHFR 677C/T and MTRR 66A/G gene polymorphisms were analyzed, and the differences in serum Hcy concentrations between patients with different genotypes were compared. RESULTS: The mutation rates of MTHFR 677C/T and MTRR 66A/G genes were 42.57% and 26.01%, respectively, and no significant differences in gene distribution frequencies were observed between men and women (P>0.05). The mean Hcy serum concentration was (16.04±4.34) μmol/L in 21 patients, including 8 patients (38.10%) with 0.05). CONCLUSION: MTHFR gene polymorphisms can affect serum Hcy concentrations. The MTHFR genotyping can be considered for individualized folic acid supplement. This conclusion should be further verified by expanding the clinical sample size.

Effect and molecular mechanism of mitochondrial solute carrier protein SLC25A26 inducing hepatoma cell senescence / 中国药理学通报

Aim To explore the regulatory effect of mitochondrial solute carrier protein SLC25A26 on senescence of hepatoma cells induced by methionine cycle metabolism. Methods HepG2 cell line was cultured in vitro. After hepatoma cell senescence was induced by toposide (2 [xmol • Ľ'), a positive drug for inducing cell senescence, methionine circulating metabolite SAM (0. 1 mmol • L " ') was treated. Western blot and Real-time PGR were used to detect the senescence indexes including pl6, p21, and HMGAl, and flow cytometry was used to detect cell cycle. Transfecting SLC25A26 overexpression plasmid, the effect of overexpressing SLC25A26 on the senescence indexes of hepatoma cells was detected by Western blot and immunofluorescence detection, and the level of SAM after overexpressing SLC25A26 was detected by the kit. The effect of overexpressing SLG25A26 on the senescence of hepatoma cells after SAM treatment was detected by Real-time PGR. Results Western blot and Real-time PGR showed that methionine cycle metabolism could weaken the senescence level of HepG2 cells induced by Etoposide, and flow cytometry showed that cell cycle was arrested in Gl phase; overexpression of SLG25A26 decreased the levels of SAM and SAH in cytoplasm of HepG2 cells, and exogenous SAM partially offset the aging effect of HepG2 cells induced by SLG25A26. Conclusions Promoting methionine cycle metabolism can inhibit hepatoma cells senescence; overexpression of SLG25A26 can induce hepatoma cells senescence; SLG25A26 can induce hepatoma cells senescence by regulating methionine cycle metabolism.

Identification of geographical origins of Cordyceps based on data of amino acids with self-organizing map neural network / 中国中药杂志

In this study, data of amino acids of Cordyceps samples from Qinghai and Tibet was analyzed with self-organizing map neural network. A model of XY-Fused network was established with the content of 8 major amino acids and total amino acids for the identification of geographical origins of Cordyceps from Qinghai and Tibet. It had the prediction accuracy of 83.3% for the test set. In addition, data mining indicated that methionine was a special kind of amino acid in Cordyceps which could serve as a marker to identify its geographical origins. On this basis, the content ratio of methionine to total amino acids was proposed to be a quantifiable indicator to distinguish Cordyceps from Qinghai and Tibet.