Junichi Sakaki

Mr. Junichi Sakaki


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 January 2021 in Molecules
Verified
Journal Article
Open access
PDF file
RHRachel Hair
Rachel Hair
JSJunichi Sakaki
Junichi Sakaki
Ock ChunOck Chun
Ock Chun
The percentage of individuals over the age of 60 is projected to reach 22% by 2050; chronic diseases associated with aging can present challenges for these individuals. Anthocyanins and the gut microbiome have each been studied as independent influencers of health. Both these factors have shown to have a positive effect on cardiovascular and bone health in individuals, as well as on the prevention or treatment of certain forms of cancers. Anthocyanins have shown to modulate the composition of the gut microbiome and may have overlapping mechanisms in the prevention and treatment of cardiovascular disease, cancer, neurodegenerative disorders and aging-associated bone loss. These health outcomes are responsible for the hospitalization and deaths of millions of Americans every year and they cost the United States billions of dollars each year to maintain, prevent and treat. Alternative methods of treatment and prevention are desired since conventional methods (surgical and pharmacological methods, physical therapy, etc.) can be costly and have significant side effects; evidence suggests that anthocyanins and the gut microbiome may be potential avenues for this. This review evaluates the findings of existing literature on the role of anthocyanins and the gut microbiome on health and their potential as a natural therapeutic agent or a target organ to provide an alternative to the conventional methods of disease prevention and treatment.

25 April 2020 in Nutrients
Verified
Journal Article
Open access
PDF file
KHKyungho Ha
Kyungho Ha
Kijoon KimKijoon Kim
Kijoon Kim
JSJunichi Sakaki
Junichi Sakaki
Ock ChunOck Chun
Ock Chun
While traditionally diet quality index scores (DQIS) as noted later in this abstract have been used to predict health outcomes, dietary total antioxidant capacity (TAC), a useful tool for assessing total antioxidant power in the diet, may also be a novel predictor. This study evaluated the associations between dietary TAC and DQIS and all-cause mortality. Based on the National Health and Nutrition Examination Survey (NHANES) 1988–1994 and 1999–2006, 23,797 US adults were followed-up until 2015. Dietary TAC and DQIS including the Healthy Eating Index-2015 (HEI-2015), Alternative Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean Diet (aMED), and Dietary Approaches to Stop Hypertension (DASH) were calculated using a 1-day 24 h dietary recall. US adults in the highest quintiles of DQIS had lower rates of all-cause mortality compared to those in the lowest quintiles (HEI-2015 hazard ratio (HR): 0.87, 95% confidence interval (CI): 0.77–0.98; AHEI-2010 HR: 0.84, 95% CI: 0.74–0.94; aMED HR: 0.79, 95% CI: 0.69–0.90; DASH HR: 0.80, 95% CI: 0.70–0.92). Similarly, those in the highest quintile of dietary TAC also had a lower all-cause mortality than those in the lowest quintile (HR: 0.88, 95% CI: 0.79–0.98). These findings suggest that dietary TAC might be a relatively valid predictor of all-cause mortality in the US population compared to the DQIS.

16 May 2021 in Nutrients
Verified
Journal Article
Open access
PDF file
Kijoon KimKijoon Kim
Kijoon Kim
MMMelissa Melough
Melissa Melough
DKDong Woo Kim
Dong Woo Kim
JSJunichi Sakaki
Junichi Sakaki
JLJoonsuk Lee
Joonsuk Lee
Ock ChunOck Chun
Ock Chun
Nutritional status affects linear growth and development. However, studies on the associations between nutritional status, diet quality, and age-standardized height in children are limited. The aim of this study was to assess the relationship between macro- and micronutrient intake and food consumption and height-for-age Z score (HAZ) among US children in the National Health and Nutrition Examination Survey (NHANES). This cross-sectional population-based study included 6116 US children aged 2–18 years. The usual dietary intake of nutrients and food groups was estimated by the multiple source method (MSM) using two-day food consumption data from NHANES 2007–2014. After adjusting for covariates, HAZ was positively associated with intakes of energy, protein, carbohydrate, fat, vitamins A, D, E, B6, and B12, thiamin, riboflavin, niacin, calcium, and iron. Children in the highest tertile of HAZ were less likely to consume lower than the EAR for vitamin E and calcium. Major foods consumed by children with lower HAZ were soft drinks, high-fat milk products, cakes, cookies, pastries, and pies, whereas children with higher HAZ tended to consume low-fat milk products, tea, and low-calorie fruit juice. These findings suggest that adequate nutritional intake, diet quality, and nutrient-dense food are important factors for height in children.

21 January 2020 in Nutrients
Verified
Journal Article
Open access
PDF file
LCLei Cao
Lei Cao
Sang Gil LeeSang Gil Lee
Sang Gil Lee
MMMelissa Melough
Melissa Melough
JSJunichi Sakaki
Junichi Sakaki
KMKendra R. Maas
Kendra R. Maas
Ock ChunOck Chun
Ock Chun
Recent studies have suggested that blackcurrant (BC) anthocyanins have promising health benefits, possibly through regulating gut microbiome. Three- and eighteen-month old female mice were fed standard mouse diets for 4 months, each with or without BC (1% w/w) supplementation (n = 3 in each treatment group, 12 in total). We then assessed gut microbiome profiles using 16S sequencing of their feces. Old mice had a less diverse microbiome community compared to young mice and there was a remarkable age-related difference in microbiome composition in the beta diversity analysis. BC supplementation did not significantly affect alpha or beta diversity. The relative abundance of several phyla, including Firmicutes, Bacteroidetes, Proteobacteria and Tenericutes, was lower in old mice. BC downregulated Firmicutes abundance in young mice and upregulated Bacteroidetes in both age groups, leading to a decreased Firmicutes/Bacteroidetes ratio. There were age-specific differences in the effect of BC supplementation on the microbiome. Twenty-four operational taxonomic units showed a significant interaction between age and BC supplementation (p < 0.01), which suggests that the ecosystem and the host health status affect the functions and efficiency of BC intake. These results indicate that BC supplementation favorably modulates gut microbiome, but there are distinct age-specific differences. Studies with human hosts are needed to better understand BC’s regulatory effects on the gut microbiome.

5 November 2018 in Nutrients
Verified
Journal Article
Open access
PDF file
JSJunichi Sakaki
Junichi Sakaki
MMMelissa Melough
Melissa Melough
Sang Gil LeeSang Gil Lee
Sang Gil Lee
JKJudy Kalinowski
Judy Kalinowski
SKSung I. Koo
Sung I. Koo
Ock ChunOck Chun
Ock Chun
Due to deleterious side effects of currently available medications, the search for novel, safe, and effective preventive agents for improving bone health in aging continues and is urgently needed. This study aimed to determine whether dietary blackcurrants (BC), an anthocyanin-rich berry, can improve bone mass in a mouse model of age-related bone loss. Thirty-five female C57BL/6J mice, 3 months old (n = 20) and 18 months old (n = 15), were randomized to consume either a standard chow diet or a standard chow diet with 1% (w/w) BC for four months. Dual-energy X-ray absorptiometry, Micro computed tomography (µCT), and histomorphometric analyses were conducted to assess bone parameters on femurs. Biochemical assays were conducted to determine bone resorption, antioxidant activity, and inflammation in humerus homogenates. Trabecular bone volume (BV/TV) was significantly lower in aged mice compared to young mice (young control, 3.7 ± 0.4% vs aged control, 1.5 ± 0.5%, mean ± SEM (standard error of mean), p < 0.01; young BC, 5.3 ± 0.6% vs aged BC, 1.1 ± 0.3%, p < 0.001). µCT analysis revealed that BC supplementation increased trabecular BV/TV in young mice by 43.2% (p < 0.05) compared to controls. Histomorphometric analysis revealed a 50% increase, though this effect was not statistically significant (p = 0.07). The osteoblast surface increased by 82.5% in aged mice with BC compared to controls (p < 0.01). In humerus homogenates of young mice, BC consumption reduced C-telopeptide of type I collagen by 12.4% (p < 0.05) and increased glutathione peroxidase by 96.4% (p < 0.05). In humerus homogenates of aged mice, BC consumption increased catalase by 12% (p = 0.09). Aged mice had significantly elevated concentrations of tumor necrosis factor α (TNF-α), a pro-inflammatory cytokine contributing to bone resorption, which was reduced by 43.3% with BC consumption (p = 0.06). These results suggest that early consumption of BC may protect from aging-associated bone loss.

6 November 2019 in Nutrients
Verified
Journal Article
Open access
PDF file
JSJunichi Sakaki
Junichi Sakaki
MMMelissa Melough
Melissa Melough
JLJing Li
Jing Li
RTRulla M. Tamimi
Rulla M. Tamimi
JCJorge E Chavarro
Jorge E Chavarro
Ock ChunOck Chun
Ock Chun
Concerns about orange juice’s sugar content have spurred discussions regarding its potential contributions to childhood obesity. The objective of this study was to evaluate the association between 100% orange juice (OJ) consumption and dietary, lifestyle and anthropometric characteristics in children and adolescents. Baseline anthropometric, dietary and lifestyle data from the Growing Up Today Study I (GUTS I) and GUTS II were collected via self-reported questionnaires from 26,554 participants. The mean values of these variables were then computed for children grouped by categories of OJ consumption, and linear trend testing was used to determine whether OJ consumption was linearly related to these variables. Multivariate adjustment modeling was used to calculate odds ratios of being obese or overweight/obese by OJ consumption. Among both boys and girls, OJ intake was positively associated with height, height-for-age z-score (HAZ), intakes of total energy, total energy excluding OJ, fruits and non-starchy vegetables and physical activity. BMI, BMI z-score and BMI-for-age percentile did not differ by OJ consumption. After adjustment for cohort, age, race, total energy intake without OJ, physical activity and screen time, prevalence of overweight/obesity significantly decreased by OJ intake in boys compared to non-consumers (odds ratio (OR) and 95% confidence interval (CI)): 1.17 (1.02, 1.33) for 1–3 glasses per month, 1.11 (0.98, 1.26) for 1–6 glasses per week, 1.00 (0.85, 1.18) for 1 glass per day, 0.91 (0.73, 1.13) for ≥1 glass per day, p-trend = 0.0403). Prevalence of obesity similarly decreased by OJ intake in boys. Prevalence of overweight/obesity and obesity did not significantly differ by OJ intake in girls. The results indicate that children consuming more OJ tended to practice healthier dietary and lifestyle habits without increased prevalence or odds of obesity or overweight.