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Makoto Shiraki

Publications and source records attributed to Makoto Shiraki.

9 recordsLinked to original sources

A longitudinal study on the nutritional state of elderly women at a nursing home in Japan.

OBJECTIVE: Elderly people at nursing homes often suffer from malnutrition, which is characterized by a loss of muscle mass and hypoalbuminemia. This malnourished state is closely associated with an impaired activity of daily living (ADL). We analyzed the nutritional state of such elderly individuals longitudinally over 3 years by anthropometry, serum albumin, and muscle and fat volume as estimated by MRI. PATIENTS AND METHODS: The subjects consisted of 16 elderly women aged 83 +/- 7 (mean +/- SD) years who resided at a nursing home in an urban area of central Japan. We determined their ADL levels using the Barthel Index (BI) at entry. Seven women belonged to group A (BI; 65-100), thus implying either a mild or no decline in ADL, while the other 9 were in group B (BI; 0-60) and they demonstrated a severe decline in ADL. We measured the following parameters every year from 2000 to 2003; anthropometry including height, body weight, arm circumference (AC), and arm muscle circumference (AMC), thigh muscle and fat volume as estimated by MRI [thigh muscle volume (TMV) and thigh fat volume (TFV)], serum albumin, and plasma amino acid levels by blood biochemistry. The anthropometric values were converted into percentages of the age- and sex-matched reference values for Japanese. RESULTS: In all subjects, the TMV, %AMC, and serum albumin level decreased significantly during the three-year period (p<0.05, respectively). The change in TMV correlated significantly with those in the %AC and %AMC (p<0.05, respectively). Group B showed significantly larger decreases in the %AMC and serum albumin level than group A. CONCLUSION: Both the muscular and visceral protein levels were found to decrease with aging in the subjects at the nursing home. This decrease depends partly on the ADL level of each subject.

Activities of Daily Living↗

Associations among maternal soy intake, isoflavone levels in urine and blood samples, and maternal and umbilical hormone concentrations (Japan).

OBJECTIVES: In utero exposure to high levels of endogenous estrogens has been hypothesized to increase breast cancer risk in later life. A high intake of soy has been suggested to protect against breast cancer. We examined the hypothesis that maternal soy intake may be inversely associated with pregnancy hormone levels. METHODS: The concentrations of hormones (estradiol, estriol, and testosterone) and isoflavones (genistein, deidzein, and equol) were measured in the maternal urine and serum, and umbilical cord blood of 194 women during pregnancy and at delivery. Soy intake during pregnancy was assessed by 5-day diet records at approximately the 29th week of pregnancy. RESULTS: High correlations were observed for isoflavone levels between maternal samples and umbilical cord blood, indicating that isoflavone can be transferred from the maternal to the fetal compartment. None of the hormones measured in umbilical cord blood was significantly associated with any of the isoflavones measured. There were a few significant associations between maternal hormone levels and isoflavone measures during pregnancy, but their patterns of associations varied by gestational week and differed depending on whether isoflavone exposure was measured by diet records, urine or serum. CONCLUSION: Our data contain no strong evidence showing that soy intake affects hormone levels during pregnancy.

Adult↗

Branched-chain amino acid catabolism in exercise and liver disease.

Branched-chain alpha-keto acid dehydrogenase (BCKDH) complex, the enzyme catalyst for the second step of the BCAA catabolic pathway, plays a central role in the regulation of BCAA catabolism. The activity of the complex is regulated by a covalent modification cycle in which phosphorylation by BCKDH kinase inactivates and dephosphorylation by BCKDH phosphatase activates the complex. Many studies suggest that control of the activity of the kinase is a primary determinant of the activity of the complex. The kinase exists at all times in the mitochondrial matrix space in two forms, with a large amount being free and a smaller amount bound rather tightly to the BCKDH complex. Only the bound form of the kinase appears to be catalytically active and, therefore, responsible for phosphorylation and inactivation of the complex. alpha-Ketoisocaproate, the transamination product of leucine and the most important known physiological inhibitor of BCKDH kinase, promotes release of the kinase from the complex. alpha-Chloroisocaproate, the analogue of leucine and the most potent known inhibitor of the kinase, is more effective than alpha-ketoisocaproate in promoting release of BCKDH kinase from the complex. Exercise and chronic liver disease (liver cirrhosis) likewise decrease the amount of the kinase bound to the complex in rat liver. The resulting activation of the BCKDH complex appears responsible for the increase in BCAA catabolism caused by exercise and liver cirrhosis. Our findings support the use of BCAA supplements for patients with liver cirrhosis.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗

Estrogen and alpha-fetoprotein levels in maternal and umbilical cord blood samples in relation to birth weight.

Birth weight has been associated with a subsequent risk of breast cancer. The present study examined associations between birth weight and pregnancy estrogens and alpha-fetoprotein (AFP). The concentrations of estradiol, estriol, and AFP were measured in maternal and umbilical cord blood samples from 194 women during pregnancy and at birth. Birth weight was significantly positively correlated with maternal serum estradiol and estriol levels in the 29th week (estradiol: r = 0.16, P = 0.03; estriol: r = 0.29, P = 0.001) and at delivery (estradiol: r = 0.20, P = 0.01; estriol: r = 0.41, P < 0.0001) after controlling for covariates. The umbilical cord estriol level was moderately but significantly correlated with birth weight (r = 0.15, P = 0.049). There was no significant association between umbilical cord serum estradiol and birth weight. There was no significant association between birth weight and maternal serum AFP in any gestational week. Umbilical cord AFP was significantly inversely correlated with birth weight (r = -0.16, P = 0.04). Umbilical cord AFP was unrelated to cord levels of estradiol and estriol. The data suggested a greater exposure to estriol and a lower exposure to AFP among high birth weight babies.

Adolescent↗

Activation of hepatic branched-chain alpha-keto acid dehydrogenase complex by tumor necrosis factor-alpha in rats.

Tumor necrosis factor-alpha (TNFalpha) promotes oxidation of branched-chain amino acids (BCAA). BCAA catabolism is regulated by branched-chain alpha-keto acid dehydrogenase (BCKDH) complex, which is regulated by phosphorylation-dephosphorylation of the E1alpha subunit at Ser293. BCKDH kinase is responsible for inactivation of the complex by phosphorylation. In the present study, we examined the effects of TNFalpha administration on hepatic BCKDH complex and kinase in rats. Rats were intravenously administered with 25 or 50 microg TNFalpha/kg body weight 4 h prior to sacrifice. The TNFalpha treatment at both doses elevated the activity state (percentage of the active form) of BCKDH complex from 22% to 69% and 86%, respectively, and the amount of phospho-Ser293 on the E1alpha subunit in each group of rats corresponded inversely to the activity state of BCKDH complex. The TNFalpha treatment of rats significantly decreased the activity as well as the bound form of BCKDH kinase. These results suggest that the decrease in the bound form of kinase is involved in the mechanism responsible for TNFalpha-induced activation of the BCKDH complex.

3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide)↗

Erectile dysfunction in patients with chronic viral liver disease: its relevance to protein malnutrition.

BACKGROUND: In patients with chronic liver disease (CLD), quality of life is generally accepted as poor, especially for physical function. However, sufficient data regarding erectile function has not been shown in patients with CLD. The international index of erectile function (IIEF) is widely used to assess erectile function, and a short form of the IIEF was recently developed (IIEF-5). Using this questionnaire, we evaluated erectile dysfunction (ED) in patients with CLD. METHODS: A total of 117 Japanese patients (64 with chronic hepatitis [CH] and 53 with liver cirrhosis [LC]) were analyzed. The etiologies were hepatitis B virus (HBV) in 21, HCV in 94, and non-B non-C in 2. The IIEF-5 and Medical Outcomes Study Short Form 36 (SF-36) were administered to the patients, and biochemical analyses for items serum albumin, prothrombin time, bilirubin, and ammonia were also performed. RESULTS: The incidence of ED was 85% in the total cohort with CLD, 78% in those with CH, and 92% in those with LC (P < 0.05 between CH and LC). ED was found in 50% of CLD patients under age 50 years, in 79% aged 50-59, and in 100% aged over 60 (P, overall <0.001). The scores for ED severity correlated with increasing grades of a modified Child-Pugh classification (P < 0.05). Simple regression analysis showed age (P < 0.01), physical function (P < 0.001), role physical (P < 0.001), and social functioning (P < 0.05) on the SF-36, and serum albumin (P < 0.001) as significant determinants of ED. Multiple regression analysis identified age (P < 0.001) and serum albumin (P < 0.001) as independent significant factors that determined ED. CONCLUSIONS: These data clearly demonstrate that liver disease is the cause of ED in patients with CLD, and serum protein status could be relevant to this condition in these patients.

Adult↗

Branched-chain amino acids as a protein- and energy-source in liver cirrhosis.

Protein-energy malnutrition (PEM) is a common manifestation in cirrhotic patients with reported incidences as high as 65-90%. PEM affects largely the patients' quality of life and survival. Thus, diagnosis of and intervention for PEM is important in the clinical management of liver cirrhosis. Supplementation with branched-chain amino acids (BCAA) is indicated to improve protein malnutrition. As an intervention for energy malnutrition, frequent meal or late evening snack has been recently recommended. Plasma amino acid analysis characterizes the patients with liver cirrhosis to have decreased BCAA. Such reduction of BCAA is explained by enhanced consumption of BCAA for ammonia detoxication and for energy generation. Supplementation with BCAA raises in vitro the synthesis and secretion of albumin by cultured rat hepatocytes without affecting albumin mRNA expression. BCAA recover the impaired turnover kinetics of albumin both in rat cirrhotic model and in cirrhotic patients. Longer-term supplementation with BCAA raises plasma albumin, benefits quality of life issues, and finally improves survival in liver cirrhosis. Recent interests focused on the timing of administration of BCAA, since daytime BCAA are usually consumed by energy generation for physical exercise of skeletal muscles. Nocturnal BCAA seem to be more favorable as a source of protein synthesis by giving higher nitrogen balance. This minireview focuses on the basic and clinical aspects of BCAA as a pharmaco-nutritional source to control PEM in liver cirrhosis.

Albumins↗