Ryuji Ochiai

Short- and long-term effects of ferulic acid on blood pressure in spontaneously hypertensive rats

Ferulic acid (4-hydroxy-3-methoxycinnamic acid) is a phenolic compound contained in rice bran and other plants. The effect of ferulic acid on blood pressure (BP) was investigated in spontaneously hypertensive rats (SHR). After oral administration of ferulic acid (1 to 100 mg/kg) to SHR, systolic blood pressure (SBP) significantly decreased in a dose-dependent manner. When oral ferulic acid (50 mg/kg) was administered to SHR, BP was lowest at 1 h and returned to basal levels at 6 h. There was a significant correlation between SHR plasma ferulic acid and changes in the SBP of the tail artery, suggesting that absorbed ferulic acid reduces BP. When 7-week-old SHR were given 10 and 50 mg/kg/d of ferulic acid for 6 weeks, increases in BP were significantly attenuated compared to SHR on the control diet. Intravenous injection of ferulic acid dose dependently reduced carotid arterial pressure in anesthetized SHR. Furthermore, the depressor effect of intravenous ferulic acid (1 mg/kg) was significantly attenuated by pretreatment of SHR with the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME; 3 mg/kg, administered intravenously). These data suggest that the hypotensive effect of ferulic acid in SHR is associated with NO-mediated vasodilation.

Coffee polyphenols improve peripheral endothelial function after glucose loading in healthy male adults

Brewed coffee is a widely consumed beverage, and many studies have examined its effects on human health. We investigated the vascular effects of coffee polyphenols (CPPs), hypothesizing that a single ingestion of CPP during glucose loading would improve endothelial function. To test this hypothesis, we conducted a randomized acute clinical intervention study with crossover design and measured reactive hyperemia index (RHI) to assess the acute effects of a 75-g glucose load with CPP in healthy, nondiabetic adult men. Blood glucose and insulin levels were elevated after glucose loading with and without CPP, with no significant differences between treatments. The RHI did not significantly decrease after glucose loading without CPP. With CPP, however, RHI significantly (P < .05) increased over baseline after glucose loading. The difference between treatments was statistically significant (P < .05). No significant changes were observed in an oxidative stress marker after glucose loading with or without CPP. These findings suggest that a single ingestion of CPP improves peripheral endothelial function after glucose loading in healthy subjects.

Effects of hydroxyhydroquinone-reduced coffee on vasoreactivity and blood pressure

Recent studies suggest that chlorogenic acids, which are the main components of the polyphenol class in coffee, decrease blood pressure, and that hydroxyhydroquinone (HHQ), which is generated by roasting coffee beans, inhibits the antihypertensive effect of chlorogenic acids in brewed coffee. Here, we examined the vasoreactivity and antihypertensive effects of HHQ-reduced coffee in mild hypertension. The study design was a double blind, randomized, placebo-controlled intervention study, with a 4-week run-in period, followed by an 8-week test beverage ingestion period. The subjects were Japanese men and women with mild hypertension and vascular failure, who were not taking any antihypertensive drugs. During the test beverage ingestion period, the subjects ingested either active or placebo HHQ-reduced coffee (chlorogenic acids per 184 ml of coffee: active, 300 mg; and placebo, 0 mg) daily. Subjects were randomly divided into two groups: active group (n=9) and placebo group (n=12). In the active beverage group, endothelium-dependent, flow-mediated vasodilation impairment was significantly ameliorated and systolic blood pressure was significantly decreased from the baseline, but not in the placebo group. There were no test beverage consumption-related changes in other parameters that may influence blood pressure, such as pulse, cardiac output, body weight or 24-h urine volume. Ingestion of the active beverage significantly decreased urinary isoprostane levels, suggesting a reduced oxidative stress. These findings indicate that HHQ-reduced coffee decreased blood pressure in subjects with mild hypertension. The decreased blood pressure was associated with improved vascular endothelial function.

Coffee bean polyphenols ameliorate postprandial endothelial dysfunction in healthy male adults

Abstract To reveal the effect of coffee bean polyphenols (CBPs) on blood vessels, this study aimed to investigate the effect of CBPs on acute postprandial endothelial dysfunction. Thirteen healthy non-diabetic men (mean age, 44.9 ± 1.4 years) consumed a test beverage (active: containing CBPs, placebo: no CBPs) before a 554-kcal test meal containing 14 g of protein, 30 g of fat and 58 g of carbohydrates. Then, a crossover analysis was performed to investigate the time-dependent changes in flow-mediated dilation (FMD) in the brachial artery. In the active group, the postprandial impairment of FMD was significantly improved, the two-hour postprandial nitric oxide metabolite levels were significantly increased and the six-hour postprandial urinary 8-epi-prostaglandin F2α levels were significantly reduced compared to the placebo group. The test meal increased the levels of blood glucose, insulin and triglycerides in both groups with no significant intergroup differences. These findings indicate that CBPs intake ameliorates postprandial endothelial dysfunction in healthy men.

Association of dietary factors with abdominal subcutaneous and visceral adiposity in Japanese men

OBJECTIVE The aim of this study was to assess the relationship between dietary factors and abdominal subcutaneous and visceral adipose tissue in overweight and obese men. METHODS A pooled cross-sectional analysis was conducted to evaluate the associations between dietary factors (nutrition, dietary pattern and alcohol consumption) and subcutaneous fat area (SFA) and visceral fat area (VFA) in 301 Japanese men, aged 21-65 years. RESULTS The standardized regression coefficients of major dietary items (total energy intake, energy intake from breakfast, lunch, supper, between-meal, protein, fat, carbohydrate and alcohol) were positive for VFA in multiple linear regression analyses with the use of age and dietary items as independent variables. The energy intake from between-meal snacks correlated with SFA (standardized regression coefficient β = 0.174, p = 0.002). The coefficient of alcohol intake was positive for VFA and negative for SFA, and alcohol intake correlated with the VFA/total fat area (TFA) ratio (β = 0.130, p = 0.009). Alcohol intake was positively correlated with the blood non-esterified fatty acid concentration. Alcohol consumption additively increased energy intake from supper. The risk of an increase to VFA ≥ 100 cm(2) was 2.02 times higher (95% CI: 1.15, 3.56) for subjects whose energy intake was ≥ 2200 kcal/d, and 2.07 times higher (95% CI: 1.26, 3.42) in those who consumed ≥ 3 g/d alcohol. The risk of an increase to a VFA/TFA ratio ≥ 0.4 was 1.81 times higher (95% CI: 1.01, 3.23) for subjects whose energy intake from supper was ≥ 1000 kcal/d. CONCLUSION Our results indicate that habitual alcohol drinking and high-energy intake from supper are associated with disproportionate accumulation of visceral fat.

Effects of subacute ingestion of chlorogenic acids on sleep architecture and energy metabolism through activity of the autonomic nervous system: a randomised, placebo-controlled, double-blinded cross over trial

Chlorogenic acids (CGA) are the most abundant polyphenols in coffee. Continuous consumption of CGA reduces body fat and body weight. Since energy metabolism and sleep are controlled by common regulatory factors, consumption of CGA might modulate sleep. Lack of sleep has been identified as a risk factor for obesity, hypertension and type 2 diabetes. The aim of this study was to determine the effects of ingesting CGA over 5 d on energy metabolism and sleep quality in humans. A total of nine healthy subjects (four male and five female) completed a placebo-controlled, double-blinded, cross-over intervention study. Subjects consumed a test beverage containing 0 or 600 mg of CGA for 5 d. On the fifth night, subjects stayed in a whole-room metabolic chamber to measure energy metabolism; sleep was evaluated using polysomnographic recording. It was found that CGA shortened sleep latency (9 (sem 2) v. 16 (sem 4) min, P<0·05) compared with the control, whereas no effect on sleep architecture, such as slow-wave sleep, rapid eye movement or waking after sleep onset, was observed. Indirect calorimetry revealed that consumption of CGA increased fat oxidation (510 (sem 84) kJ/8 h (122 (sem 20) kcal/8 h) v. 331 (sem 79) kJ/8 h (81 (sem 19) kcal/8 h), P<0·05) but did not affect energy expenditure during sleep. Consumption of CGA enhanced parasympathetic activity assessed from heart-rate variability during sleep (999 (sem 77) v. 919 (sem 54), P<0·05). A period of 5-d CGA consumption significantly increased fat oxidation during sleep, suggesting that beverages containing CGA may be beneficial to reduce body fat and prevent obesity. Consumption of CGA shortened sleep latency and did not adversely affect sleep quality.

Safety evaluation of the consumption of high dose milk fat globule membrane in healthy adults: a double-blind, randomized controlled trial with parallel group design.

Consumption of milk fat globule membrane (MFGM) in combination with habitual exercise suppresses age-associated muscle loss. The effects of high dose MFGM, however, are not known. A double-blind, randomized controlled trial with parallel group design was conducted to evaluate the safety of consuming high dose MFGM tablets. The subjects were 32 healthy adult men and women. Subjects were given 5 times the recommended daily intake of the tablets containing 6.5 g of MFGM or whole milk powder for 4 weeks. Stomach discomfort and diarrhea were observed; however, these symptoms were transitory and slight and were not related to consumption of the test tablets. In addition, there were no clinically significant changes in anthropometric measurements or blood tests. Total degree of safety assessed by the physicians of all subjects was “safe.” These findings suggest that consumption of the tablets containing 6.5 g MFGM for 4 weeks is safe for healthy adults. Graphical Abstract The consumption of high dose MFGM tablets for 4 weeks in healthy adults was considered to be safe.

Effect of Chlorogenic Acid Intake on Cognitive Function in the Elderly: A Pilot Study

Objective To evaluate the effect of chlorogenic acids (CGAs) intake on cognitive function. Methods In this pilot study, the Cogstate and CNS Vital Signs test batteries were used to evaluate cognitive function in 8 healthy elderly men and women complaining of subjective memory loss after a 6-month intake of a test beverage containing 330 mg of CGAs just before bedtime. Results After a 6-month CGA intake period, significant improvement was observed in the One Back Test of the Cogstate, the Shifting Attention Test, and Finger Tapping Test as well as in the composite memory, verbal memory, complex attention, cognitive flexibility, executive function, and motor speed domains of the CNS Vital Signs test battery. Conclusion A 6-month intake of CGAs may improve attentional, executive, and memory functions in the elderly with complaints of subjective memory loss.

Effect of Chlorogenic Acids on Cognitive Function: A Randomized, Double-Blind, Placebo-Controlled Trial

(1) Background: Chlorogenic acids (CGAs) have been attracting interest of late, owing to their health benefits. Here, we performed a randomized, double-blind, placebo-controlled trial to investigate whether CGAs improved cognitive function in humans. (2) Methods: Thirty-eight healthy participants were assigned to either the CGA group, which was given CGA-added beverage daily for 16 weeks, or the placebo group. Cognitive functions were assessed using the Japanese version of the CNS Vital Signs (Cognitrax). (3) Results: The CGA group showed significant increase in the Cognitrax domain scores for motor speed, psychomotor speed, and executive function compared with the placebo group, as well as an improvement in the shifting attention test scores. In blood analysis, the CGA group showed increased levels of apolipoprotein A1 and transthyretin, both of which are putative biomarkers for early-stage cognitive decline. (4) Conclusions: These results suggest that CGAs may improve some cognitive functions, which would help in the efficient performance of complex tasks.

Effects of dietary supplementation with milk fat globule membrane on the physical performance of community-dwelling Japanese adults: a randomised, double-blind, placebo-controlled trial

We conducted a randomised, double-blind, placebo-controlled trial to elucidate the effects of dietary milk fat globule membrane (MFGM) on the physical performance of community-dwelling Japanese adults. For this 24-week study, 115 middle-aged subjects (range 50–70 years old) were invited, of whom 113 (seventy-two women, forty-one men) completed the trial. Participants were then divided into either the placebo control or MFGM group. Measurements of physical performance (without undertaking any mandatory exercise) examining muscle strength, agility and balance were tested every 6 weeks until 24 weeks. Analyses were performed using the intention-to-treat method for all participants. Although the effects of MFGM on muscle strength and agility were not significant, we noted that the parameter for balance (such as the ability to stand on one leg with eyes closed for longer durations) increased in the MFGM group (mean 10·1 (95 % CI 8·25, 12·4) s) compared with the placebo (mean 7·53 (95 % CI 6·11, 9·30) s) (P = 0·046). Similarly, application of the mixed-effect model for repeated measures under unstructured covariance also revealed that the effect of MFGM was significant when compared with the placebo (10·2 (95 % CI 8·33, 12·4) v. 7·61 (95 % CI 6·17, 9·30) s) (P = 0·045). In conclusion, we demonstrated that MFGM had an effect on the physical performance of community-dwelling Japanese adults despite mandatory exercise. However, studies using larger cohorts of individuals from different demographic backgrounds are required to further elucidate the mechanisms underlying these effects and to extend the application of MFGM.