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Branched-chain amino acids (BCAAs) are essential for muscle protein synthesis and are widely acknowledged for mitigating sarcopenia. Oligonol® (Olg), a low-molecular-weight polyphenol from Litchi chinensis, has also been found to attenuate sarcopenia by improving mitochondrial quality and positive protein turnover. This study aims to investigate the effect of Olg on BCAA-stimulated protein synthesis in sarcopenia. In sarcopenic C57BL/6 mice and senescence-accelerated mouse-prone 8 (SAMP8) mice, BCAAs were significantly decreased in skeletal muscle but increased in blood serum. Furthermore, the expressions of membrane L-type amino acid transporter 1 (LAT1) and branched-chain amino acid transaminase 2 (BCAT2) in skeletal muscle were lower in aged mice than in young mice. The administration of Olg for 8 weeks significantly increased the expressions of membrane LAT1 and BCAT2 in the skeletal muscle when compared with non-treated SAMP8 mice. We further found that BCAA deprivation via LAT1-siRNA in C2C12 myotubes inhibited the signaling of protein synthesis and facilitated ubiquitination degradation of BCAT2. In C2C12 cells mimicking sarcopenia, Olg combined with BCAA supplementation enhanced mTOR/p70S6K activity more than BCAA alone. However, blocked LAT1 by JPH203 reversed the synergistic effect of the combination of Olg and BCAAs. Taken together, changes in LAT1 and BCAT2 during aging profoundly alter BCAA availability and nutrient signaling in aged mice. Olg increases BCAA-stimulated protein synthesis via modulating BCAA transportation and BCAA catabolism. Combining Olg and BCAAs may be a useful nutritional strategy for alleviating sarcopenia. [ABSTRACT FROM AUTHOR]

The effects of maternal vitamin E supplementation on the antioxidant status of chicks were investigated. Female breeder chicks were fed corn-soybean growing diets without supplemental vitamin E for a 17-wk developmental period. After 17 wk, the birds were randomly assigned to 5 treatments and fed corn-soybean diets supplemented with 0, 40, 80, 120, and 160 mg/kg vitamin E (all-rac-[alpha]-tocopherol acetate), respectively. Blood samples were collected and pullets were artificially inseminated at 35 wk of age. Eggs laid beginning on d 2 after insemination were placed in an incubator. At the time of hatching, 12 chicks from each treatment were randomly sampled and killed. Livers and brains of chicks were collected for the subsequent evaluation of antioxidant status. Plasma vitamin E concentrations increased linearly (P < 0.001 ; r = 0.997) with the increase in supplemental vitamin E, but those in egg yolk reached a plateau at 120 mg/kg supplemental vitamin E. The malondialdehyde (MDA) concentration, an indicator of lipid peroxidation, of chick brain decreased linearly (P < 0.01; r = -0.909) with the increase in supplemental vitamin E. Pullets given 160 mg/kg supplemental vitamin E had lower plasma MDA concentrations than those given 0 mg/kg (P < 0.05). Similar results were found for the reactive oxygen species levels, an indicator of oxidative stress, of chick brain and liver. For antioxidant enzymes, chicks of pullets given 120 mg/kg supplemental vitamin E had higher (P < 0.05) activities of liver catalase than those given 0-80 mg/kg. Chicks of pullets given 160 mg/kg supplemental vitamin E had higher (P < 0.05) activities of brain superoxide dismutase than those given 0-40 mg/kg. These results indicated that maternal supplementation with high levels of vitamin E (120-160 mg/kg) enhances antioxidant capability and depresses oxidative stress in chicks. KEY WORDS: * vitamin E * maternal supplementation * antioxidant capability * chicks

Although the combination of chemotherapy and radiotherapy has increased the survival rate of patients with nasopharyngeal carcinoma (NPC), certain patients do not respond well to the treatment and have a poor prognosis. Therefore, novel therapeutic drugs and strategies to improve prognosis of patients with NPC are required. As certain plant extracts can suppress the viability of cancer cells, the present study investigated whether oligonol, a polyphenolic compound primarily found in lychee fruit, exerts anticancer activities in NPC cells. MTT, ELISA and immunoblotting were performed to investigate cell survival, cytokeratin-18 fragment release, and the expression of apoptosis and autophagy markers, respectively. Oligonol decreased the viability of NPC-TW01 and NPC/HK1NPC cell lines. Oligonol increased the protein expression of several apoptosis markers, including cleaved caspase-8 and -3, cleaved PARP and cytokeratin 18 fragment. Moreover, it also increased expression of autophagy markers Beclin 1 and LC3-II, as well as LC3-II/LC3-I ratio in both NPC cell lines. Furthermore, treatment with autophagy inhibitors 3-methyladenine or LY294002 significantly increased oligonol-induced viability inhibition in NPC-TW01 cells. Combined treatment of oligonol + LY294002 reduced LC3-II expression and the LC3II/LC3I ratio while increasing cleaved caspase-8 and -3, cleaved PARP and cytokeratin 18 fragment expression in NPC-TW01 cells. These findings indicated autophagy inhibitors could enhance viability inhibition and apoptotic effects induced by oligonol in NPC cells. [ABSTRACT FROM AUTHOR]

Because of limited available information, the Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) of vitamin B-6 for adolescents were recently estimated by extrapolation from adult values. To determine vitamin B-6 requirements and to provide recommendations for intakes, vitamin B-6 intake, nutritional status and anthropometry were studied in 134 healthy adolescents (63 boys and 71 girls) aged 13-15 y in Tainan, Taiwan. Direct and indirect vitamin B-6 indicators were measured in plasma, erythrocytes and urine. The anthropometric data of the adolescents in this study were similar to those of the first Nutrition and Health Survey in Taiwan (NAHSIT), conducted from 1993 to 1996, showing the normal growth and development of this adolescent group. All subjects had plasma pyridoxal-5'-phosphate (PLP) concentrations [greater than or equal to] 20 nmol/L, indicating an adequate vitamin B-6 status. The mean dietary vitamin B-6 intakes of boys and girls were 1.04 [+ or -] 0.24 and 0.83 [+ or -] 0.26 mg/d, respectively. Vitamin B-6 status indicators, including plasma PLP, erythrocyte alanine activity coefficient (EALT-AC), aspartate aminotransferase activity coefficient (EAST-AC) and urinary 4-pyridoxic acid (4-PA), were correlated with vitamin B-6 intake (r = 0.84, -0.84, -0.77 and 0.86, respectively, P < 0.01). Adequate values of plasma PLP ([greater than or equal to] 20 nmol/L), EALT-AC (3.0 [micro]mol/d) were used to determine the EAR according to the Dietary Reference Intake committee methodology. The present study suggests that vitamin B-6 EAR (RDA) for adolescent boys and girls aged 13-15 y are 1.07 (1.28) and 0.90 (1.08) mg/d, respectively. J. Nutr. 133: 3191-3194, 2003. KEY WORDS: * vitamin B-6 * nutritional status * Estimated Average Requirement * Recommended Dietary Allowance * adolescent

The Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) of vitamin B-6 for children were recently estimated by extrapolating from adult values because of limited available information. To determine vitamin B-6 requirements and provide recommendations for intakes, vitamin B-6 intake, nutritional status and anthropometry of 168 healthy children (79 boys and 89 girls) were studied in Tainan, Taiwan. Direct and indirect vitamin B-6 status indicators were measured in plasma, erythrocytes and urine. Anthropometric data of children in this study were similar to those of the first Nutrition and Health Survey in Taiwan (NAHSIT) conducted in 1993-1996. The plasma pyridoxal phosphate (PLP) concentration of each child was [greater than or equal to] 30 nmol/L, indicating an adequate vitamin B-6 status. Daily dietary vitamin B-6 intakes of boys and girls were 0.80 [+ or -] 0.16 and 0.74 [+ or -] 0.16 mg/d, respectively. Daily dietary vitamin B-6 intakes of children who had adequate urinary 4- pyridoxic acid (4-PA) (>3.0/[micro]mol/L), erythrocyte alanine aminotransferase activity coefficient (EALT-AC) ( KEY WORDS: * vitamin B-6 * nutritional status * Estimated Average Requirement * Recommended Dietary Allowance * school children

Mild hyperhomocysteinemia is an independent risk factor for cardiovascular disease and may result from a deficiency of folate, vitamin B-6 or vitamin B-12. Because vitamin B-12 deficiency is often associated with vegetarianism, this study was designed to examine the effect of Taiwanese vegetarian diets on B-vitamin status and plasma homocysteine levels. Female Buddhist lacto-vegetarians (n = 45; 31-45 y) and matched omnivores (n = 45) recruited in Hualien, Taiwan, were investigated. Taiwanese vegetarians consumed normal amount of folate, but only 21% of Taiwan Recommended Daily Nutrient Allowances (RDNA) values of vitamin B-12. Compared with the omnivores, the vegetarians had significantly higher levels of plasma folate (14.79 [+ or -] 7.70 vs. 11.98 [+ or -] 8.29 nmol/L), but lower levels of vitamin B-12 (207.7 [+ or -] 127.1 vs. 403.5 [+ or -] 138.9 pmol/L). Fasting plasma homocysteine levels were significantly higher in vegetarians than in omnivores (mean: 11.20 [+ or -] 4.27 vs. 8.64 [+ or -] 2.06 [micro]mol/L; median: 10.5 vs. 8.5 [micro]mol/L). Fasting plasma homocysteine was inversely correlated with plasma folate and vitamin B-12 in the vegetarian group. Multiple regression analysis revealed that plasma folate, vitamin B-12 and creatinine were independent determinants of homocysteine variation and contributed to 38.6% of homocysteine variation in the vegetarians. Compared with the omnivores, vegetarians also had significantly lower serum levels of valine, isoleucine, leucine, lysine, alanine and arginine, but higher levels of glycine. In the vegetarian group, fasting plasma homocysteine correlated negatively with serum threonine, lysine, histidine, arginine and cystine, and these amino acids contributed to 38.7% of homocysteine variation. In conclusion, the Buddhist nuns who consumed a lacto-vegetarian diet had mildly elevated fasting plasma homocysteine levels presumably due to lower levels of plasma vitamin B-12. J. Nutr. 132 152-158, 2002. KEY WORDS: * vegetarian diet * homocysteine * vitamin B-12 * folate * humans

Abstract Background Early enteral nutrition is recommended in cases of critical illness. It is unclear whether this recommendation is of most benefit to extremely ill patients. We aim to determine the association between illness severity and commencement of enteral feeding. Methods One hundred and eight critically ill patients were grouped as “less severe” and “more severe” for this cross-sectional, retrospective observational study. The cut off value was based on Acute Physiology and Chronic Health Evaluation II score 20. Patients who received enteral feeding within 48 h of medical intensive care unit (ICU) admission were considered early feeding cases otherwise they were assessed as late feeding cases. Feeding complications (gastric retention/vomiting/diarrhea/gastrointestinal bleeding), length of ICU stay, length of hospital stay, ventilator-associated pneumonia, hospital mortality, nutritional intake, serum albumin, serum prealbumin, nitrogen balance (NB), and 24-h urinary urea nitrogen data were collected over 21 days. Results There were no differences in measured outcomes between early and late feedings for less severely ill patients. Among more severely ill patients, however, the early feeding group showed improved serum albumin (p = 0.036) and prealbumin (p = 0.014) but worsened NB (p = 0.01), more feeding complications (p = 0.005), and prolonged ICU stays (p = 0.005) compared to their late feeding counterparts. Conclusions There is a significant association between severity of illness and timing of enteral feeding initiation. In more severe illness, early feeding was associated with improved nutritional outcomes, while late feeding was associated with reduced feeding complications and length of ICU stay. However, the feeding complications of more severely ill early feeders can be handled without significantly affecting nutritional intake and there is no eventual difference in length of hospital stay or mortality between groups. Consequently, early feeding shows to be a more beneficial nutritional intervention option than late feeding in patients with more severe illness.

Epstein-Barr virus (EBV) infection is associated with B cell lymphomas in humans. The latent membrane protein 1 (LMP-1) of EBV constitutively activates the JAK/STAT signaling pathway and contributes to the proliferation of EBV-infected primary human B lymphocytes. Thus, targeting LMP1-induced JAK/STAT signaling may prove effective in treating B-cell lymphomas. The extract of the fruiting body of Antrodia cinnamomea, has been reported to have cytotoxicity on blood cancer cells. Here, we report that the bioactivity of antcin H, an analog of the JAK2 inhibitor zhankuic acid A (ZAA), inhibits LMP1-induced JAK/STAT related signaling and induces lymphoma cell line apoptosis. Moreover, antcin H enhances low-dose methotrexate (MTX) cytotoxicity against lymphoma cells. Treatment of antcin H with low-dose MTX significantly suppressed tumor growth and prolonged the survival of tumor-bearing mice. Our findings indicate antcin H as a potential therapeutic agent for the treatment of EBV-infected cancer cells. [ABSTRACT FROM AUTHOR]