High-intensity exercise impairs intestinal barrier function by generating oxidative stress.

The intestine functions as a barrier preventing the entry of extrinsic factors into the body. This barrier function is disrupted by oxidative damage along with an impaired mucosal layer. Excessive exercise can generate oxidative stress in the intestinal tissue; however, the effect of exercise-induced oxidative stress on intestinal permeability is unclear. In this study, we examined the involvement of oxidative stress in barrier function of the ileum of mice following high-intensity exercise. Male ICR mice (12-week-old) were divided into sedentary and exercise groups. Mice in the exercise group underwent a single bout of treadmill running, and the ileum was collected for histological and biochemical analyses. Plasma fluorescence intensity level after oral administration of fluorescein isothiocyanate-dextran gradually increased until 30 min after exercise in response to intensity of exercise. Relatively high levels of oxidative proteins and low level of claudin-1, a tight-junction protein, were observed in the exercise group. Treatment with a xanthine oxidase inhibitor suppressed exercise-induced increases in intestinal permeability. Moreover, excessive exercise training for two weeks led to relatively high intestinal permeability at rest. These results suggest that high-intensity exercise increases intestinal permeability and tight junction damage, which may be mediated by oxidative stress.

Matcha green tea beverage moderates fatigue and supports resistance training-induced adaptation.

BACKGROUND: Resistance training adaptively increases muscle strength and mass, contributing to athletic performance and health promotion. Dietary intervention with natural foods provides nutrients that help accelerate muscle adaptation to training. Matcha green tea contains several bioactive factors such as antioxidants, amino acids, and dietary fibers; however, its effect on muscle adaptation is unclear. In this study, we aimed to investigate the effects of matcha beverage intake on muscle adaptation to resistance training. METHODS: Healthy, untrained men were randomized into placebo and matcha groups. Participants consumed either a matcha beverage containing 1.5 g of matcha green tea powder or a placebo beverage twice a day and engaged in resistance training programs for 8 (trial 1) or 12 weeks (trial 2). RESULTS: In trial 1, maximum leg strength after training tended to increase more in the matcha group than that in the placebo group. In the matcha group, subjective fatigue after exercise at 1 week of training was lower than that in the placebo group. Gut microbe analysis showed that the abundance of five genera changed after matcha intake. The change in Ruminococcus, Butyricimonas, and Oscillospira compositions positively correlated with the change in maximum strength. In trial 2, the change in skeletal muscle mass in response to training was larger in the matcha group. In addition, the salivary cortisol level was lower in the matcha group than that in the placebo group. CONCLUSION: Daily intake of matcha green tea beverages may help in muscle adaptation to training, with modulations in stress and fatigue responses and microbiota composition.

Effects of amino acids and albumin administration on albumin metabolism in surgically stressed rats: A basic nutritional study.

BACKGROUND: Nutrition therapy and administration of albumin preparations are common in postsurgical patients. However, the effects of these interventions on albumin metabolism are unclear. We elucidated the effect of postoperative albumin and/or parenteral nutrition administration on it. METHODS: Sprague-Dawley rats underwent surgery involving intestinal rubbing followed by intestinal exposure. Subsequently, they were administered experimental solutions for 48 h, their blood samples were collected at 24 and 48 h, and livers were excised at 48 h. Based on experimental solutions, rats were divided into five groups: non-surgical (Non-surg); glucose and electrolyte solution (GE); amino acid, glucose, and electrolyte solution (AGE); GE + rat serum albumin (Alb) (GE + Alb); and AGE + Alb. Their plasma albumin concentrations; albumin fractional synthesis rate (ALB FSR); mercaptoalbumin/total albumin ratio (MA ratio); and messenger RNA (mRNA) expressions of albumin and hepatocyte nuclear factor-1 (HNF-1) in the liver were measured. RESULTS: The GE and AGE groups showed significant decline in albumin concentrations. ALB FSR was significantly enhanced in the AGE group compared with the GE group. The mRNA expression of albumin was similar to ALB FSR in all groups and that of HNF-1 was significantly decreased in the GE + Alb and AGE + Alb groups compared with the Non-surg group. The MA ratio in the AGE group was similar to the Non-surg group. CONCLUSION: The administration of amino acids comprising parenteral nutrition after surgery augmented ALB FSR and maintained the MA ratio only without simultaneous albumin administration.

An Evaluation of the Protein Requirements of Japanese Young Men by Consuming Two Types of Dairy Proteins Using the Indicator Amino Acid Oxidation Method.

The indicator amino acid oxidation method is a relatively new method for determining protein requirements. Our hypothesis was that the protein requirement of the casein-whey protein mixture (70% casein and 30% whey protein) was lower than the protein requirement of plain casein, because casein and whey proteins compensate for the lack of the first-limiting amino acids. The optimal mixing ratio was determined based on the amino acid scoring pattern which is used to calculate the digestible indispensable amino acid score. In this study, digestibility was not considered to determine the optimal mixing ratio because dairy protein is a good source of digestible protein. This study aimed to evaluate the protein requirements of Japanese young men by consuming casein and casein-whey protein mixture. Ten healthy young men (22±0.2 y old) participated in 12 experiments according to a graded protein intake (0.5, 0.7, 0.9, 1.0, 1.2, 1.4 g/kg/d) of casein and casein-whey protein mixture. The mean protein requirement was calculated as the breakpoint of breath 13CO2 enrichment using change-point regression models. The mean protein requirements of Japanese young men by consuming casein and casein-whey protein mixture were estimated to be 1.00 g/kg/d and 0.90 g/kg/d, respectively. These estimated requirements were consistent with the protein quality expected from the amount of the first-limiting amino acids. The indicator amino acid oxidation method may be useful to evaluate protein quality.

Household Income Is Related to Dietary Fiber Intake and Dietary Acid Load in People with Type 2 Diabetes: A Cross-Sectional Study.

Household income was related to habitual dietary intake in general Japanese people. This cross-sectional study investigated the relationship between household income and habitual dietary intake in people with type 2 diabetes mellitus (T2DM). Household income was evaluated using a self-reported questionnaire and categorized into high and low household income. Nutritional status was assessed using a brief-type self-administered diet history questionnaire. Among 128 men and 73 women, the proportions of participants with low household income were 67.2% (n = 86/128) in men and 83.6% (n = 61/73) in women. Dietary fiber intake (11.3 ± 4.2 vs. 13.8 ± 6.0 g/day, p = 0.006) was lower, and dietary acid load, net endogenous aid production score (NEAP) (51.7 ± 10.5 vs. 46.8 ± 10.4 mEq/day, p = 0.014) and potential renal acid load score (PRAL) (9.5 ± 10.7 vs. 3.7 ± 14.1 mEq/day, p = 0.011) were higher in men with low household income than in those without. Multivariable linear regression analyses demonstrated that log (dietary fiber intake) in men with low household income was lower than that in those with high household income after adjusting for covariates (2.35 [2.26−2.44] vs. 2.52 [2.41−2.62], p = 0.010). Furthermore, NEAP (54.6 [51.7−57.4] vs. 45.8 [42.5−49.2], p <0.001) in men with low household income were higher than in those with high household income after adjusting for covariates. Contrastingly, household income was not related to diet quality in women. This study showed that household income was related to dietary fiber intake and dietary acid load in men but not in women.

A nutritional intervention that promotes increased vegetable intake in Japanese with non-alcoholic fatty liver disease: a six-month trial.

The aim of this study was to investigate whether a nutritional intervention motivating increased vegetable consumption would be an effective treatment and diet therapy for patients with non-alcoholic fatty liver disease. We examined 15 patients with this disease (5 men and 10 women). During the 6-month intervention period, all participants received a small amount of vegetables twice a month as a nutritional education tool aimed at increasing vegetable consumption. They also received nutritional counseling and underwent ultrasound and blood biochemical examinations at baseline and 3 and 6 months after initiation of the intervention. Moreover, they were requested to submit dietary records for any 2 days. Green, white, and total vegetable intakes were significantly higher at 3 and 6 months than at baseline in 8 patients. These patients had significantly lower alanine amino-transferase and triglyceride concentrations than those whose vegetable intake did not increase. Additionally, green vegetable intake significantly negatively correlated with weight at 3 and 6 months (r = -0.617, p = 0.032 and r = -0.848, p = 0.008, respectively). These results suggest that our nutritional approach effectively increased vegetable consumption in at least some patients with non-alcoholic fatty liver disease, consequently improving their condition.

Cystine supplementation sustains plasma mercaptalbumin levels in rats fed low-protein diets more effectively than methionine.

We recently reported that dietary cystine maintained plasma mercaptalbumin levels in rats fed low-protein diets. The present study aimed to compare the influence of low-protein diets supplemented with cystine and methionine, which is another sulfur amino acid, on plasma mercaptalbumin levels in rats. Male Sprague-Dawley rats were fed a 20% soy protein isolate diet (control group), 5% soy protein isolate diet (low-protein group) or 5% soy protein isolate diet supplemented with either methionine (low-protein + Met group) or cystine (low-protein + Cyss group) for 1 week. The percentage of mercaptalbumin within total plasma albumin of the low-protein + Met group was significantly lower than that of the control and low-protein + Cyss groups. No significant differences in the mRNA levels of tumor necrosis factor-α, interleukin-6, interleukin-1ß, and cyclooxygenase 2 in blood cells were observed between the low-protein + Met and low-protein + Cyss groups. Treatment with buthionine-(S,R)-sulfoximine, an inhibitor of glutathione synthesis, did not influence the percentage of mercaptalbumin within total plasma albumin in rats fed the low-protein diet supplemented with cystine. These results suggest that supplementation with cystine may be more effective than that with methionine to maintain plasma mercaptalbumin levels in rats with protein malnutrition. Cystine might regulate plasma mercaptalbumin levels via the glutathione-independent pathway.

Changes in iron metabolism centered on hepcidin due to high-intensity exercise under restricted food intake.

OBJECTIVES: The purpose of this study was to observe changes in iron metabolism of rats due to high-intensity exercise during reduced food intake. METHODS: Thirty-six, 4-wk-old male Wistar rats were divided into six groups after being acclimated to running: rested control, intense exercise, 80% feeding and rested, 80% feeding and intense exercise, 70% feeding diet and rested, and 70% feeding and intense exercise groups. Only three intense exercise groups underwent acute running sessions for 30 min (30 m/min) once a day for 7 d. RESULTS: Rats did not develop anemia with exercise and food intake restriction. Serum iron levels, transferrin saturation, hepcidin-25, and hepatic iron levels in the exercise groups were lower than those in the respective resting groups. However, these values in the 70% diet groups were slightly higher than those in the 80% diet groups. Serum erythropoietin levels decreased as food intake decreased, but the serum erythropoietin level in the 70% feeding and intense exercise group was similar to that in the rested control group. Serum interleukin-6 levels were significantly lower in the groups with restricted food intake than in the free-fed group, and exercise had no effect. CONCLUSIONS: High-intensity exercise under restricted food intake may significantly alter the iron metabolism to maintain blood cell levels due to the strong promotion of metabolic iron utilization in response to dietary iron depletion, increased iron demand, and excretion.

Astaxanthin-, ß-Carotene-, and Resveratrol-Rich Foods Support Resistance Training-Induced Adaptation.

Resistance training adaptively increases the muscle strength associated with protein anabolism. Previously, we showed that the combined intake of astaxanthin, ß-carotene, and resveratrol can accelerate protein anabolism in the skeletal muscle of mice. The purpose of this study was to investigate the effect of anabolic nutrient-rich foods on muscle adaptation induced by resistance training. Twenty-six healthy men were divided into control and intervention groups. All participants underwent a resistance training program twice a week for 10 weeks. Astaxanthin-, ß-carotene-, and resveratrol-rich foods were provided to the intervention group. Body composition, nutrient intake, maximal voluntary contraction of leg extension, oxygen consumption, and serum carbonylated protein level were measured before and after training. The skeletal muscle mass was higher after training than before training in both groups (p < 0.05). Maximal voluntary contraction was increased after training in the intervention group (p < 0.05), but not significantly increased in the control group. Resting oxygen consumption was higher after training in the intervention group only (p < 0.05). As an oxidative stress marker, serum carbonylated protein level tended to be lower immediately after exercise than before exercise in the intervention group only (p = 0.056). Intake of astaxanthin-, ß-carotene-, and resveratrol-rich foods supported resistance training-induced strength and metabolic adaptations.

Polysorbate 80-induced leaky gut impairs skeletal muscle metabolism in mice.

Impaired intestinal permeability can induce systemic inflammation and metabolic disturbance. However, the effect of impaired intestinal permeability on metabolic function in the skeletal muscle is unknown. Dietary polysorbate 80 (PS80), a common emulsifier, has been shown to impair intestinal permeability in mice. Here, we investigated the effect of PS80-induced intestinal permeability on glucose tolerance with metabolic signaling in the skeletal muscle. Male ICR mice were divided into control and PS80 groups. In the PS80 group, PS80 was contained in the drinking water at 1% (w/v). After 4 weeks, plasma fluorescein isothiocyanate (FITC) intensity was measured after orally administering FITC-dextran. Half of the mice in each group underwent running exercises. Metabolic and inflammatory parameters were examined in the blood and skeletal muscle. Plasma FITC and lipopolysaccharide levels were higher in the PS80 group than the control group (p < .01, p = .085). The expression of tumor necrosis factor-α in the skeletal muscle was increased upon PS80 administration (p < .05). Although the homeostasis model assessment ratio was higher in the PS80-fed mice (p < .05), insulin-signaling activity in the muscle did not differ between groups. Muscular pH, mitochondrial cytochrome oxidase activity, and glycogen content after exercise were lower in the PS80 group (p < .05) than the control group. There was a negative correlation between plasma FITC and muscle glycogen levels in the exercised groups (r = -.60, p < .05). These results suggest that daily PS80 intake induces intestinal permeability, leading to glucose intolerance and mitochondrial dysfunction in the skeletal muscle.

Combined intake of astaxanthin, ß-carotene, and resveratrol elevates protein synthesis during muscle hypertrophy in mice.

OBJECTIVE: The antioxidant factors, astaxanthin, ß-carotene, and resveratrol, have a potential effect on protein synthesis in skeletal muscle and a combined intake may have a greater cumulative effect than individual intake. The aim of this study was to investigate the combined effects on skeletal muscle mass and protein metabolic signaling during the hypertrophic process from atrophy in mice. METHODS: Male ICR mice were divided into five dietary groups consisting of seven animals each: normal, astaxanthin, ß-carotene, resveratrol, and all three antioxidants. Equal concentrations (0.06% [w/w]) of the respective antioxidants were included in the diet of each group. In the mixed group, three antioxidants were added in equal proportion. One leg of each mouse was casted for 3 wk to induce muscle atrophy. After removal of the cast, the mice were fed each diet for 2 wk. The muscle tissues were collected, weighed, and examined for protein metabolism signaling and oxidative damage. RESULTS: The weight of the soleus muscle was increased in the astaxanthin, ß-carotene, and resveratrol groups to a greater extent than in the normal group; this was accelerated by intake of the mixed antioxidants (P = 0.007). Phosphorylation levels of mammalian target of rapamycin and p70 S6 K in the muscle were higher in the mixed antioxidant group than in the normal group (P = 0.025; P = 0.020). The carbonylated protein concentration was lower in the mixed antioxidant group than in the normal group (P = 0.021). CONCLUSIONS: These results suggested that a combination of astaxanthin, ß-carotene, and resveratrol, even in small amounts, promoted protein synthesis during the muscle hypertrophic process following atrophy.

Protein intake is not associated with progression of diabetic kidney disease in patients without macroalbuminuria.

BACKGROUND: Diabetic kidney disease is an important problem in individuals with diabetes. The effect of dietary protein intake on the renal function of patients with diabetes is controversial. Here, we sought to clarify the association between dietary protein intake and changes in the urinary albumin excretion (UAE) or estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes. METHODS: In this retrospective cohort study, we included 144 patients (70 men, mean ± standard deviation of age 64 ± 10 years, and median (interquartile range) of UAE 15.0 (7.0-38.9) mg/gCr) without an eGFR less than 30 mL/min/1.73 m2 and/or UAE greater than or equal to 300 mg/gCr. Changes in the UAE or eGFR were defined as (logarithms [UAE+1] or eGFR at follow-up minus logarithms [UAE+1] or eGFR at baseline examination)/follow-up duration (years). Habitual protein intake was estimated by a self-administered diet history questionnaire. RESULTS: The median follow-up duration was 5 years. Protein intake (g/kg ideal body weight/day) was not associated with the change in the UAE (r = -0.130, p = 0.120) or change in the eGFR (r = -0.074, p = 0.381). Multiple linear regression analyses showed that after adjusting for covariates, the patients' protein intake was not associated with change in their UAE (standardized regression coefficient: 0.044, p = 0.732) or change in their eGFR (standardized regression coefficient: 0.250, p = 0.085). CONCLUSIONS: Dietary protein intake does not influence changes in the UAE or eGFR among patients with type 2 diabetes without macroalbuminuria.

Sarcopenia is associated with tongue pressure in older patients with type 2 diabetes: A cross-sectional study of the KAMOGAWA-DM cohort study.

AIM: Death as a result of pneumonia is an important issue in patients with diabetes. Tongue pressure is associated with swallowing function, which has a close association with aspiration pneumonia. However, no previous studies have shown the association between sarcopenia and tongue pressure in older patients with type 2 diabetes. METHODS: In the present cross-sectional study, we investigated body composition, handgrip strength and tongue pressure. Skeletal muscle mass index (kg/m2 ) was defined as appendicular muscle mass / the square of the height. Sarcopenia was defined when both handgrip strength <26 kg for men and <18 kg for women, and the skeletal muscle mass index <7.0 kg/m2 for men and <5.7 kg/m2 for women existed. RESULTS: Among 144 patients (82 men, 71.4 years [SD 6.7 years]), 11.8% had sarcopenia. Tongue pressure was associated with skeletal muscle mass index and handgrip strength (r = 0.361, P < 0.001 and r = 0.387, P < 0.001, respectively, in men; and r = 0.300, P = 0.018 and r = 0.538, P < 0.001, respectively, in women). Tongue pressure was associated with the prevalence of sarcopenia after adjusting for covariates (OR 3.83, 95% CI 1.06-13.9, P = 0.041). According to the receiver operating characteristic curve analysis, the optimal cut-off value of handgrip strength for the presence of low tongue pressure was 27.7 kg (AUC 0.70, 95% CI 0.53-0.83, sensitivity 0.78, specificity 0.64) in men and 18.3 kg (AUC 0.71, 95% CI 0.54-0.84, sensitivity 0.82, specificity 0.54) in women. CONCLUSIONS: Sarcopenia, especially handgrip strength, is associated with tongue pressure in older patients with type 2 diabetes. We should consider a decrease of swallowing function when examining patients with sarcopenia. Geriatr Gerontol Int 2019; 19: 153-158.

Increased Ratio of Non-mercaptalbumin-1 Among Total Plasma Albumin Demonstrates Potential Protein Undernutrition in Adult Rats.

The redox state of plasma albumin shifts in response to dietary protein intake in growing rats, and the shift is more sensitive than that of plasma albumin level, a classical marker of protein nutritional status. While it has been suggested that plasma albumin redox state could be useful as a novel marker of protein nutritional status, the above animal model is highly sensitive to dietary protein intake and the observation may not be extrapolated widely to humans. This study aimed to investigate whether albumin redox state also reflects protein nutritional status in adult rats, which have a lower dietary protein requirement and are less responsive to protein intake. Male adult rats were placed on AIN-93M diet (14% casein), or AIN-93M-based low protein diets (10 or 5% casein) ad libitum for 24 weeks. Whereas there was no significant difference in body weight between the groups at the end of the experimental period, the 5% casein diet group had the smallest gastrocnemius muscle weight among the groups, which was significantly lower than that of the 10% casein diet group. Plasma albumin level was also lower in the 5% casein diet group compared with the other groups, but the differences were limited and inconsistent during the experimental period. Among the albumin redox isoforms such as mercaptalbumin, non-mercaptalbumin-1, and non-mercaptalbumin-2, the ratio of non-mercaptalbumin-1 among total albumin was significantly higher in the 5% casein diet group, and the increase remained constant throughout the experimental period. Increased non-mercaptalbumin-1 ratio would thus demonstrate the presence of potential protein undernutrition in adult rats, as manifested only by a decreased gain in a specific type of skeletal muscle; non-mercaptalbumin-1 among total albumin ratio could be useful as a robust marker of protein nutritional status, contributing to prevention of protein undernutrition-related diseases such as frailty and sarcopenia.

Dietary cystine is important to maintain plasma mercaptalbumin levels in rats fed low-protein diets.

The oxidized/reduced state of plasma albumin in rats is influenced by the quantity of dietary protein. However, the effects of the protein quality on the oxidized/reduced state of plasma albumin are not clear. We hypothesized that the quality of dietary protein might modulate the oxidized/reduced state of plasma albumin. The aim of the present study was to examine whether the amino acid composition of dietary protein modulates the oxidized/reduced state of plasma albumin in rats. Male Sprague-Dawley rats were fed low-protein diets containing 5% casein (CA), 5% egg white (EW), or 6% wheat gluten (WG) for 2 weeks. The plasma albumin concentration gradually decreased in rats fed each diet; however, there was no significant difference among the groups. In rats fed the 5% CA diet, the percentage of mercaptalbumin within the total plasma albumin was significantly lower than in those fed the EW or WG diet. Compared with EW or WG, CA contains lower amounts of glycine and cystine. In rats fed a 5% CA diet supplemented with cystine, the percentage of mercaptalbumin was significantly higher than that in rats fed a 5% CA diet supplemented with glycine. The expression of hepatic eukaryotic initiation factor 4E-binding protein 1 was significantly lower in rats fed the cystine-supplemented diet than in those fed the glycine-supplemented diet. These results suggest that dietary protein with a high cystine content maintains plasma mercaptalbumin levels in rats fed low-protein diets.

Intake of Carbohydrate to Fiber Ratio Is a Useful Marker for Metabolic Syndrome in Patients with Type 2 Diabetes: A Cross-Sectional Study.

BACKGROUND/AIMS: The effect of low carbohydrate diet on human health is still controversial. Whole grain, which is carbohydrate rich in fiber, has protective effects on human health. Thus, we assumed that intake of carbohydrate to fiber ratio has an important role in human health. METHODS: This is a post-hoc analysis of a cross-sectional study of 164 patients with type 2 diabetes. Habitual food and nutrient intake were assessed and estimated by a self-administered diet history questionnaire. Intake of carbohydrate to fiber ratio was defined as carbohydrate (g)/fiber intake (g). Logistic regression analyses were performed to reveal the association between intake of carbohydrate to fiber ratio and metabolic syndrome (MetS). RESULTS: Intake of carbohydrate to fiber ratio has closely associated with metabolic parameters, including triglycerides (r = 0.21, p = 0.007) and high-density lipoprotein cholesterol (r = -0.23, p = 0.003). Intake of carbohydrate to fiber ratio was associated with MetS (OR 1.06 [95% CI 1.00-1.13], p = 0.047) after adjusting for covariates, whereas carbohydrate intake (1.00 [0.99-1.01], p = 0.752) or carbohydrate energy/total energy (1.00 [0.94-1.07], p = 0.962) was not associated with MetS. CONCLUSIONS: Intake of carbohydrate to fiber ratio was associated with MetS, whereas carbohydrate intake was not.

Urinary pH reflects dietary acid load in patients with type 2 diabetes.

Dietary acid load is important information, however, survey of food intake needs time and skill. Therefore, it is difficult to survey food intake from all patients. It remains to be elucidated the association between dietary acid load and urinary pH in patients with type 2 diabetes. In this cross-sectional study of 173 patients, we investigated the relationship between urinary pH and dietary acid load, assessed with potential renal acid load. Habitual food and nutrient intake was assessed by a self-administered diet history questionnaire. Urinary pH was negatively correlated with potential renal acid load (r = -0.24, p = 0.002). Multivariate regression analysis revealed that potential renal acid load (standardized regression coefficient = -0.21, p = 0.036) was associated with urinary pH after adjusting for covariates. In addition, according to the receiver operator characteristic analysis, the optimal cut-off point of urinary pH for high dietary acid load, defined as potential renal acid load over 7.0 mEq/day was 5.7 (area under the receiver operator characteristic curve 0.63 (95% CI 0.54-0.71), sensitivity = 0.56, specificity = 0.70, p = 0.004). Urinary pH was associated with dietary acid load in patients with type 2 diabetes. We suggest that urinary pH can be a practical screening marker for dietary acid load in patients with type 2 diabetes.

Validity of the Short Nutritional Assessment Questionnaire for Japanese Patients with Cancer Undergoing Outpatient Chemotherapy.

PURPOSE: To investigate the utility of the Short Nutritional Assessment Questionnaire (SNAQ) in the nutritional evaluation of patients with cancer undergoing outpatient chemotherapy. METHODS: We included 229 patients with cancer who were undergoing outpatient chemotherapy between October 2015 and April 2016. The SNAQ and the revised SNAQ (addition of age and body mass index) were implemented, and their relationships with Controlling Nutritional Status (CONUT), an indicator of bionutritional assessment, were examined. RESULTS: The cutoff value of the SNAQ score corresponding to moderate-to-severe undernourishment in CONUT values was 0.5, with a sensitivity of 87.5% and a specificity of 65.9%, and the corresponding values for the revised SNAQ score were 2.5, 91.7%, and 62.9%, respectively. This cutoff value and the corresponding positive prediction value for the revised SNAQ were superior to those of SNAQ. Binary logistic regression analysis with the revised SNAQ and sex as independent variables and the CONUT value as the dependent variable revealed that the higher the SNAQ score, the more likely it was that CONUT moderate-to-severe undernourishment would be identified (odds ratio, 1.48;, 1.34-1.96). CONCLUSION: Nutritional evaluation with the revised SNAQ can predict moderate-to-severe undernourishment according to CONUT in patients with cancer undergoing outpatient chemotherapy. J. Med. Invest. 64: 117-121, February, 2017.

An oxidized/reduced state of plasma albumin reflects malnutrition due to an insufficient diet in rats.

We examined whether protein- and food-intake restrictions modulate the oxidized/reduced state of plasma albumin in Sprague-Dawley rats. Rats were fed a 3%, 5%, 10% or 20% casein diet for 2 weeks. The plasma albumin concentration significantly decreased with decreasing protein intake. However, no significant difference in plasma albumin concentration was seen between rats fed the 5% or 10% casein diet. In rats fed the 5% casein diet, the percentage of mercaptalbumin within total plasma albumin was significantly lower and that of nonmercaptalbumin-1 was significantly higher than in rats fed the 10% casein diet. In experiments with food-intake restriction for 2 weeks, rats were fed 50% or 75% of the amount of a 20% casein diet consumed by control rats. The percentage of mercaptalbumin was significantly lower and that of nonmercaptalbumin-2 was significantly higher in rats with food-intake restriction than in control rats. When rats with malnutrition were refed with the 20% casein diet ad libitum, the percentage of mercaptalbumin rapidly increased. The change in the percentage of mercaptalbumin was correlated with the plasma transthyretin concentration. These results indicate that the oxidized/reduced state of plasma albumin may be applied as a sensitive marker of nutritional status reflecting dietary pattern.

The reduced/oxidized state of plasma albumin is modulated by dietary protein intake partly via albumin synthesis rate in rats.

The reduced/oxidized state of plasma albumin is influenced by many factors, including chronic diseases and strenuous training. Recently, the reduced/oxidized state has also been shown to be associated with dietary protein and energy intakes in rats. We hypothesized that dietary protein intake may modulate the reduced/oxidized state of plasma albumin by altering the rate of albumin synthesis and that the reduced/oxidized state could therefore serve as a novel marker of protein undernutrition. We tested this hypothesis by examining male growing rats placed on a low-protein or energy-restriction diet. In the 4-week experiment, animals fed a low-protein diet (3% casein), whose dietary intakes were lower than those fed control diet (20% casein), showed significant decreases in plasma albumin level and the ratio of the reduced form of albumin to total albumin. Animals given the same amount of control diet as the low-protein diet group (approximately 30% energy restriction) also showed the above decreases, albeit to much more limited extents. The ratio of reduced to total plasma albumin correlated significantly with plasma albumin fractional synthesis rate. When animals were maintained on the low-protein diet for as long as 12 weeks and then fed the control diet for 1 week, the decreased ratio of reduced to total plasma albumin, but not plasma albumin level, resolved rapidly. The reduced/oxidized state of plasma albumin would thus reflect dietary protein status via plasma albumin turnover including the fractional synthesis rate and could prove useful as a sensitive marker of protein undernutrition.