The applicability of a commercial 3DO body scanner in measuring body composition in Chinese adults with overweight and obesity: a secondary analysis based on a weight-loss clinical trial

BACKGROUND

A commercial three-dimensional optical (3DO) scanning system was reported to be used in body composition assessment. However, the applicability in Chinese adults has yet to be well-studied.

METHODS

This secondary analysis was based on a 16-week weight-loss clinical trial with an optional extension to 24 weeks. Waist and hip circumference and body composition were measured by 3DO scanning at each follow-up visit during the study. Bioelectrical impedance analysis (BIA) was also performed to confirm the reliability of 3DO scanning at each visit. We used Lin's concordance correlation coefficients (CCC) to evaluate the correlation between the two methods above-mentioned. Bland-Altman analysis was also performed to evaluate the agreement and potential bias between different methods.

RESULTS

A total number of 70 Chinese adults overweight and obese (23 men and 47 women, aged 31.8 ± 5.8 years) were included in the analysis, which resulted in 350 3DO scans and corresponding 350 BIA measurements. The percent body fat, fat mass, and fat-free mass were 33.9 ± 5.4%, 26.7 ± 4.6 kg, and 50.3 ± 8.7 kg before the trial by 3DO scanning. And they were 30.5 ± 5.8%, 22.5 ± 4.7 kg, and 49.4 ± 8.3 kg after 16 weeks of the trial. Compared with BIA, 3DO scanning performed best in the assessment of fat-free mass (CCC = 0.89, 95%CI: 0.86, 0.90), then followed by fat mass (CCC = 0.76, 95%CI: 0.71, 0.80) and percent body fat (CCC = 0.70, 95%CI: 0.64, 0.75). Subgroup analysis showed that 3DO scanning and BIA correlated better in women than that in men, and correlated better in measuring fat-free mass in participants with larger body weight (BMI ≥28.0 kg/m2) than those with smaller body weight (<28.0 kg/m2).

CONCLUSIONS

3DO scanning is an effective technology to monitor changes in body composition in Chinese adults overweight and obese. However its accuracy and reliability in different ethnicities needs further exploration.

Effect of cinnamon spice on continuously monitored glycemic response in adults with prediabetes: a 4-week randomized controlled crossover trial

BACKGROUND

Previous clinical studies showing that cinnamon spice lowers blood glucose concentrations had inconsistent results.

OBJECTIVES

To determine the effect of daily cinnamon spice supplementation in an amount commonly used for seasoning on glucose concentrations in adults with obesity and prediabetes.

METHODS

Following a 2-wk run-in period of maintaining a low polyphenol/fiber diet, 18 participants with obesity and prediabetes underwent a 10-wk randomized, controlled, double-blind, crossover trial (mean age 51.1 y; mean fasting plasma glucose 102.9 mg/dL). The participants were randomly assigned to take cinnamon (4 g/d) or placebo for 4-wk, followed by a 2-wk washout period, and then crossed over to the other intervention for an additional 4-wk. Glucose changes were measured with continuous glucose monitoring. Oral glucose tolerance testing immediately following ingestion of cinnamon or placebo was performed at 4-time points to assess their acute effects both at the baseline and end of each intervention phase. Digestive symptom logs were obtained daily.

RESULTS

There were 694 follow-up days with 66,624 glucose observations. When compared with placebo, 24-h glucose concentrations were significantly lower when cinnamon was administered [mixed-models; effect size (ES) = 0.96; 95 % confidence interval (CI): -2.9, -1.5; P < 0.001]. Similarly, the mean net-area-under-the-curve (netAUC) for glucose was significantly lower than for placebo when cinnamon was given (over 24 h; ES = -0.66; 95 % CI: 2501.7, 5412.1, P = 0.01). Cinnamon supplementation resulted in lower glucose peaks compared with placebo (Δpeak 9.56 ± 9.1 mg/dL compared with 11.73 ± 8.0 mg/dL; ES = -0.57; 95 % CI: 0.8, 3.7, P = 0.027). Glucose-dependent-insulinotropic-polypeptide concentrations increased during oral glucose tolerance testing + cinnamon testing (mixed-models; ES = 0.51; 95 % CI: 1.56, 100.1, P = 0.04), whereas triglyceride concentrations decreased (mixed-models; ES = 0.55; 95 % CI: -16.0, -1.6, P = 0.02). Treatment adherence was excellent in both groups (cinnamon: 97.6 ± 3.4 % compared with placebo: 97.9 ± 3.7 %; ES = -0.15; 95 % CI: -1.8, 0.2, P = 0.5). No differences were found in digestive symptoms (abdominal pain, borborygmi, bloating, excess flatus, and stools/day) between cinnamon and placebo groups.

CONCLUSIONS

Cinnamon, a widely available and low-cost supplement, may contribute to better glucose control when added to the diet in people who have obesity-related prediabetes. This trial was registered at clinicaltrials.gov as NCT04342624.

Concentrated Grape Powder Consumption Modulates Cholesterol Metabolism and Homeostasis in Healthy Subjects

SCOPE

Four weeks' of concentrated grape powder (GP) consumption reduces circulating cholesterol in healthy free-living subjects consuming a low-fiber/low-polyphenol diet. Here, the study aims to investigate the underlying mechanisms for cholesterol reduction by evaluating biomarkers of cholesterol de novo biosynthesis, intestinal absorption, miRNA involved in transcriptional regulation of cholesterol metabolism, as well as cholesterol oxidation.

METHODS AND RESULTS

Fasting plasma samples collected from 19 healthy free-living subjects at baseline and week 4 of GP consumption are used in this study. Gas chromatography-mass (GC-MS) analysis of plasma samples shows that lathosterol, a precursor of cholesterol synthesis, is significantly decreased after GP consumption indicating reduced cholesterol de novo biosynthesis. Markers of intestinal absorption, campesterol, and β-sitosterol are not changed. Realtime PCR shows that plasma exosomal miRNA-1 is increased after GP consumption. GC-MS also shows that GP consumption reduces the plasma cholesterol oxidation product 27-hydroxycholesterol (27-HC).

CONCLUSIONS

This study enhances the understanding of the mechanisms of the cholesterol lowering effects of GP, and provides new insights into the potential health benefits of grape consumption.

Mixed Nuts as Healthy Snacks: Effect on Tryptophan Metabolism and Cardiovascular Risk Factors

We recently demonstrated that the consumption of mixed tree nuts (MTNs) during caloric restriction decreased cardiovascular risk factors and increased satiety. Tryptophan (Trp) metabolism has been indicated as a factor in cardiovascular disease. Here, we investigated the effect of MTNs on Trp metabolism and the link to cardiovascular risk markers. Plasma and stool were collected from 95 overweight individuals who consumed either MTNs (or pretzels) daily as part of a hypocaloric weight loss diet for 12 weeks followed by an isocaloric weight maintenance program for an additional 12 weeks. Plasma and fecal samples were evaluated for Trp metabolites by LC-MS and for gut microbiota by 16S rRNA sequencing. Trp-kynurenine metabolism was reduced only in the MTNs group during weight loss (baseline vs. week 12). Changes in Trp-serotonin (week 24) and Trp-indole (week 12) metabolism from baseline were increased in the MTNs group compared to the pretzel group. Intergroup analysis between MTN and pretzel groups does not identify significant microbial changes as indicated by alpha diversity and beta diversity. Changes in the relative abundance of genus Paludicola during intervention are statistically different between the MTNs and pretzel group with p < 0.001 (q = 0.07). Our findings suggest that consumption of MTNs affects Trp host and microbial metabolism in overweight and obese subjects.

Avocado Consumption Increased Skin Elasticity and Firmness in Women - A Pilot Study

BACKGROUND

Avocados are a rich dietary source of monounsaturated fatty acids, carotenoids, and phenolic compounds. Clinical studies have demonstrated that oral consumption of carotenoids improved skin aging. However, no studies have investigated whether oral intake of avocado will reduce skin aging.

OBJECTIVES

We therefore performed this pilot study to assess whether oral consumption of one avocado daily for 8 weeks can reduce skin aging in healthy overweight women assessing skin physical characteristics and resistance to UVB radiation.

METHODS

Thirty-nine female participants (age 27-73 years) with Fitzpatrick skin type II-IV were randomly assigned to consume either one avocado daily or continue habitual diet for 8 weeks. Facial skin elasticity, firmness, pigmentation, sebum, and hydration were determined using a cutometer on the forehead and under eye. Minimal erythema dose (MED) was determined by standardized protocol at inner arm.

RESULTS

Elasticity and firmness were increased at forehead comparing 8 weeks to baseline in the avocado group. Comparing avocado to control, change in firmness marker from baseline to week 8 indicated a significant increase in forehead skin firmness in the avocado group. We did not observe any change in hydration, pigmentation, sebum, and UVB resistance between the avocado and control group, although changes in melanin and erythema were observed in both groups over time.

CONCLUSIONS

Our findings suggest that daily oral avocado consumption may lead to enhanced elasticity and firmness of the facial skin in healthy women. Further studies of other skin locations are required to establish the connection between avocado consumption and skin aging.

Mixed Nuts as Healthy Snack: Effect on Gut Microbiota and Tryptophan Metabolism

Objectives

We recently demonstrated that the consumption of mixed tree nuts (MTNs) as part of a hypocaloric diet decreased heart rate and increased satiety. MTNs can be categorized as a high tryptophan (Trp) food and disturbed Trp metabolism has been associated with cardiovascular disease. The fiber and polyphenol content of MTNs have been suggested to affect human health in part through the gut microbiome. Here, we aim to investigate the effect of MTNs on Trp metabolism and the gut microbiome and the link to cardiovascular markers and satiety.

Methods

Stool and plasma samples at baseline, week 12 and 24 from our recent randomized, controlled, two-arm study were studied. In the study 95 overweight individuals consuming 1.5 oz. of MTNs (n = 56) or pretzel snack (n = 38) daily as part of a hypocaloric (−500 kcal) weight loss diet for 12 weeks followed by an isocaloric weight maintenance program for additional 12 weeks. Trp metabolites kynurenine (KYN), kynurenic acid (KYNA), Trp, indole sulfate (IS), indole propionate (IPA) and indole acetate (IAA) were analyzed by LC-MS and HPLC. Gut microbiota will be analyzed by 16S rRNA sequencing.

Results

At baseline, a positive correlation was observed between heart rate and serum KYN levels and KYN/Trp ratio, as well as between BMI and KYN/Trp ratio. Compared to baseline, KYN levels were significantly reduced in the MTN group at the end of 12 week weight loss phase (P = 0.04) and returned to baseline concentration after 12 weeks of isocaloric weight maintenance program (baseline vs. week 12 vs. week 24: 357 ± 124 vs. 339 + 103 vs. 362 ± 137 ng/mL), but not in pretzel group (418 + 431 vs. 347 ± 150 vs. 375 + 171 ng/mL). Other Trp metabolites evaluatedwere not changed during intervention in either groups. The gut microbiome analysis is ongoing.

Conclusions

We identified a positive association between Try-KYN metabolism and heart rate and BMI in overweight individuals. MTN consumption may directly affect Trp-KYN metabolism.

Funding Sources

International Tree Nut Council Nutrition Research and Education Foundation.

Pomegranate juice alters the microbiota in breast milk and infant stool: a pilot study

Pomegranate juice (PomJ) contains ellagitannins (ETs) that are metabolized to ellagic acid (EA). Intestinal bacteria convert EA further to urolithins that are absorbed into the circulation and may provide health benefits. PomJ consumption by pregnant women was reported to be neuroprotective for their infants. In order to determine whether EA and metabolites are transferred from breast milk of mothers consuming PomJ to nursing infants, we performed an interventional pilot study and enrolled ten healthy women with full-term, exclusively breast-fed infants, consuming 8 oz. of PomJ daily for two weeks. Breast milk, plasma, urine and stool samples were collected from the mothers and the urine and stool samples from the infants before and after two weeks of PomJ consumption. Samples were analyzed using liquid chromatography-mass spectrometry to identify EA metabolites and 16S rRNA sequencing to determine changes in the microbiota. EA metabolite conjugates (dimethyl EA-glucuronide DMEAG and urolithin A-glucuronide UAG) were found in breast milk, plasma and urine from mothers and in urine of infants after 14 days of PomJ consumption. In addition, urolithin B-glucuronide (UBG) was found in breast milk, plasma and urine from two participants and urine from their infants. PomJ consumption was associated with a significant decrease in breast milk of Lactococcus, Subdoligranulum, and Acinetobacter, while the abundance of Firmicutes/Faecalibacterium increased significantly. In breast milk Escherichia/Shigella was inversely correlated to breast milk UAG. In infant stools, the abundance of Lachnoclostridium and Staphylococcus was increased. Infant stool Blautia was positively correlated to breast milk and mother plasma UBG. This pilot study demonstrates that EA and its metabolites are absorbed by the nursing infant from breast milk, excreted in urine and impact the infant gut microbiome. The concentration of EA metabolites in breast milk increased over time. Phenolic compounds in breast milk could be a way to promote neuroprotective, antioxidant and anti-inflammatory health benefits in infants.

The Impact of Obesity on SARS-CoV-2 Pandemic Mortality Risk

The COVID-19 pandemic has uncovered the increased susceptibility of individuals with obesity to infection and severe disease leading to hospitalization and death. Studies in New York City demonstrated that after advanced age, obesity was the most common risk factor leading to severe disease and death from COVID-19. While the connection has been recognized, there has not been a general recognition of the potential mechanisms for this link between excess body fat and mortality from this viral pandemic including respiratory complications and sequelae of increased activation of the immune system. Despite plans for vaccination of the global population, the risk community spread of COVID-19 and future pandemics will be linked in part to obesity and immunity. This review will detail a number of potential mechanisms through which obesity may contribute to the lethality of this viral infection. These insights will hopefully lead to a greater emphasis on obesity prevention and treatment as part of the global response to this and future pandemic threats.

Including Mixed Tree Nut Snacks in a Weight Loss and Weight Maintenance Intervention Resulted in Weight Loss and Increased Satiety

Objectives

Tree nuts are an excellent dietary source of protein and healthy fat leading to increased satiety. Tree nuts also provide polyphenols, vitamins and minerals supporting the immune response. However, there is a concern that tree nuts are not suitable to be included in a weight loss diet due to their fat content. Therefore, it was the objective of the study to test whether including mixed tree nuts in a weight loss and maintenance program will lead to weight loss by increasing satiety and decreasing inflammation.

Methods

We performed a randomized, controlled, two-arm study in 95 overweight individuals consuming 1.5 oz of mixed tree nuts daily (n = 56) or equal amount of calories in the form of a pretzel snack (n = 39) as part of a hypocaloric weight loss diet (−500 calories of resting metabolic rate) for 12 wks followed by an isocaloric weight maintenance program for an additional 12 wks.

Results

The dropout rate was significantly lower in the tree nut (16.4%) compared to the pretzel (35.9%) group. Participants experienced significant weight loss (12 wks: −1.6 and −1.9 and 24 wks: −1.5 kg and −1.4 kg) in the tree nut and pretzel group, respectively, without difference between groups at any time point. In addition, both groups showed a significant decrease in diastolic blood pressure at 12 wks and a significant increase in satiety at 24 wks, but only participants in the mixed tree nut group showed significant decrease in heart rate at 4, 12 and 24 wks. Plasma oleic acid concentration was significantly increased at 12 and 24 wks in the tree nut group, while in the pretzel group plasma oleic acid was significantly increased and stearic acid decreased at 12 wks and linolenic acid was increased at 24 wks. No change in fasting plasma triglyceride, total cholesterol and HDL-cholesterol was observed in both groups. No change in inflammatory markers except plasma MCP-1 was decreased significantly in the tree nut group at 4 wks.

Conclusions

In summary, including mixed tree nuts in a weight loss and maintenance diet can maintain compliance and promote weight loss similar to standard weight loss and maintenance diets. Although both, the mixed tree nut diet and pretzel diet resulted in decreased diastolic blood pressure, only consumption of the mixed tree nut diet led to significantly decreased heart rate and increased study retention.

Funding Sources

International Tree Nut Council.

Effect of Dietary Fermentable Carbohydrate Supplementation on Amino Acid Homeostasis

Objectives

Homeostasis of amino acids (AA) such as branched chain AAs (BCAAs), and aromatic AAs are associated with glucose regulation. Fermentable carbohydrates (FC), such as xylooligosaccharide (XOS), have been shown to improve glucose and lipid metabolism. Therefore, we aim to study the potential of dietary FC to modulate systemic and tissue specific amino acid (AA) homeostasis in normal physiological condition. Two FCs of different molecular size were included in this study, XOS (0.3–1 kDa) and a new sulfated fucose containing polysaccharide (SPS) isolated from seaweed (82 kDa).

Methods

Male C57BL6 mice at age 7 week were randomized into three groups and fed AIN93M, AIN93M supplemented with 2% XOS or SPS (w/w) for 8 weeks (n = 6–8/group). SPS was prepared from Laminaria japonica. At the end of the intervention, fasting serum samples were collected and processed for glucose, insulin, AA analysis. Liver and skeletal muscle samples were frozen and processed for AA analysis.

Results

Blood glucose was significantly lower in XOS-fed mice but not SPS-fed mice compared to mice fed the control AIN93M diet. No significant differences in blood insulin, lipids, AA as well as body weight and fat depots were observed among the three experimental groups (XOS, SPS and control). In skeletal muscle, the concentration of total free AA, as well as 9 AAs (Asp, Glu, Arg, Tyr, Met, Phe and BCAAs) was significantly lower and 1 AA (Thr) was higher in SPS mice compared to control mice, while free AA levels in skeletal muscle were not significantly different between XOS and control mice. In liver, levels of total free AA, Arg, Thr and leucine metabolite ketoleucine were significantly lower in XOS mice compared to control mice. No significant change in free AA levels in liver was observed between SPS and control mice.

Conclusions

Our data show the differential modulation of systemic and tissue-specific AA and glucose homeostasis by dietary XOS and SPS intake, indicating the key role that AA signaling may play in metabolic homeostasis.

Funding Sources

This project was supported by the National Institutes of Health and UCLA Center for Human Nutrition.

Almond Consumption Increased UVB Resistance in Healthy Asian Women

Objectives

Almonds are a rich source of phenolic and polyphenolic compounds, which have antioxidant activity. In vitro and in vivo studies have demonstrated that topical application of almond oil and almond skin extract reduces UVB-induced photoaging. Ultraviolet-B (UVB) protection by oral almond consumption has not been previously studied in humans. It was the objective to investigate whether oral almond consumption can increase resistance to UVB radiation and reduce skin aging in healthy Asian women.

Methods

Thirty-nine female participants (18–45 years) with Fitzpatrick skin type II-IV were randomly assigned to consume either 1.5 oz of almonds or 1.8 oz of pretzels daily for 12 weeks. Minimal erythema dose (MED) was determined using a standardized protocol, which determined the minimal radiation inducing erythema on the inner arm 24 hours following UVB exposure. Facial skin texture was evaluated by two dermatologists using the Clinician's Erythema Assessment scale and Allergan Roughness scale. Facial melanin index, hydration, sebum, and erythema were determined using a cutometer.

Results

Women who consumed almonds, experienced a significant increase in MED from 415 ± 64 to 487 ± 59 (18.7 ± 19.2%, P = 0.006) from baseline to week 12 compared to women in the pretzel group from 415 ± 67 to 421 ± 67 (1.8 ± 11.1%). The exposure time to reach minimal erythema was also increased significantly in the almond group from 160 ± 23 to 187 ± 25 (17.5 ± 22.2%) compared to the pretzel group from 165 ± 27 to 166 ± 25 (1.7 ± 14%) (p=0.026). There were no differences noted between the groups consuming almonds versus pretzels in Allergan roughness, melanin, hydration, or sebum on facial skin.

Conclusions

Our findings suggest that daily oral almond consumption may lead to enhanced protection from UVB photodamage by increasing the MED. Protection from other UV radiation was not tested and therefore almond consumption will not replace other methods of sun protection such as application of sunscreen or wearing protective closing.

Funding Sources

Almond Board of California.

Mixed Tree Nut Snacks Compared to Refined Carbohydrate Snacks Resulted in Weight Loss and Increased Satiety during Both Weight Loss and Weight Maintenance: A 24-Week Randomized Controlled Trial

Mixed tree nuts (MTNs) are an excellent source of protein and healthy fat contributing to satiety. However, their relatively high caloric content might not be beneficial in a weight loss diet. The present study was designed to test whether including MTNs in a weight loss and maintenance program interferes with weight management compared to a refined carbohydrate pretzel snack (PS). We performed a randomized, controlled, two-arm study in 95 overweight individuals consuming 1.5 oz of MTNs or PS daily as part of a hypocaloric weight loss diet (−500 kcal) over 12 weeks followed by an isocaloric weight maintenance program for 12 weeks. Participants in both groups experienced significant weight loss (12 weeks: −1.6 and −1.9 and 24 weeks: −1.5 and −1.4 kg) compared to baseline in the MTN and PS groups, respectively. However, there was no difference in weight loss and other outcome parameters between the MTN and PS groups. The MTN group showed a significant increase in satiety at 24 weeks. Both groups had a decrease in diastolic blood pressure at 12 weeks. Participants in the MTN group showed significant decreases in heart rate at 4, 12, and 24 weeks. Plasma oleic acid was significantly increased at 12 and 24 weeks in the MTN group but only at 12 weeks in the PS group. Plasma MCP-1 was decreased significantly in the MTN group at 4 weeks. In summary, participants in both groups lost weight, but only the MTN intervention increased satiety at 24 weeks, enhanced retention, decreased heart rate, and increased serum oleic acid at 24 weeks.

The Effect of Broccoli Sprout Extract on Seasonal Grass Pollen-Induced Allergic Rhinitis

Patients exposed to pollutants are more likely to suffer from allergic rhinitis and may benefit from antioxidant treatment. Our study determined if patients diagnosed with grass-induced allergic rhinitis could benefit from broccoli sprout extract (BSE) supplementation. In total, 47 patients were confirmed with grass-induced allergic rhinitis and randomized to one of four groups: group 1 (nasal steroid spray + BSE), group 2 (nasal steroid spray + placebo tablet), group 3 (saline nasal spray + BSE) and group 4 (saline nasal spray + placebo tablet). Peak Nasal Inspiratory Flow (PNIF), Total Nasal Symptoms Scores (TNSS) and nasal mucus cytokine levels were analyzed in samples collected before and after the 3-week intervention. Comparing before and after the intervention, PNIF improved significantly when comparing Groups 1 and 2, vs. placebo, at various time points (p ≤ 0.05 at 5, 15, 60 and 240 min) following nasal challenge, while TNSS was only statistically significant at 5 (p = 0.03), 15 (p = 0.057) and 30 (p = 0.05) minutes. There were no statistically significant differences in various cytokine markers before and after the intervention. Combining nasal corticosteroid with BSE led to the most significant improvement in objective measures.

Almond consumption increased UVB resistance in healthy Asian women

BACKGROUND

Almonds are a rich source of phenolic and polyphenolic compounds, which have antioxidant activity. In vitro and in vivo studies have demonstrated that topical application of almond oil and almond skin extract reduces UVB-induced photoaging. Ultraviolet-B (UVB) protection by oral almond consumption has not been previously studied in humans.

OBJECTIVES

To investigate whether oral almond consumption can increase resistance to UVB radiation and reduce skin aging in healthy Asian women.

METHODS

Thirty-nine female participants (18-45 years) with Fitzpatrick skin type II-IV were randomly assigned to consume either 1.5 oz of almonds or 1.8 oz of pretzels daily for 12 weeks. Minimal erythema dose (MED) was determined using a standardized protocol, which determined the minimal radiation needed to induce erythema on the inner arm following UVB exposure. Facial skin texture was evaluated by two dermatologists using the Clinician's Erythema Assessment scale and Allergan Roughness scale. Facial melanin index, hydration, sebum, and erythema were determined using a cutometer.

RESULTS

The MED was increased in the subjects consuming almonds compared to the control group consuming pretzels. There were no differences noted between the groups consuming almonds versus pretzels in Allergan roughness, melanin, hydration, or sebum on facial skin.

CONCLUSIONS

Our findings suggest that daily oral almond consumption may lead to enhanced protection from UV photodamage by increasing the MED.

Acute Effects of Cinnamon Spice on Post-prandial Glucose and Insulin in Normal Weight and Overweight/Obese Subjects: A Pilot Study

Clinical studies and meta-analyses have supported the notion that consuming cinnamon spice long term can have beneficial effects in individuals with normal glucose homeostasis and varying degrees of glucose intolerance including type 2 diabetes. The objective of this study was to evaluate the acute effect of cinnamon on the post-prandial responses to a typical American breakfast in normal and overweight/obese participants (ClinicalTrials.gov registration No. NCT04686552). The consumption of a single dose of 6 g of cinnamon added to oatmeal prepared with milk resulted in a significant reduction of one of our primary outcomes post-prandial insulin response (niAUC_0−180min) in overweight/obese participants compared to control consuming breakfast without cinnamon. We also performed exploratory analysis of secondary outcomes. In normal weight participants, we observed a decrease of post-prandial glucagon response (niAUC_0−180min and glucagon levels at 60–120 min) and C-peptide response (30 min) comparing breakfast with to without cinnamon. Cinnamon consumption did not change post-prandial glycemic response in normal weight participants, but increased 60 min post-prandial glucose in overweight/obese participants compared to control. In summary, cinnamon consumption differentially affected post-prandial hormonal responses in normal and overweight/obese participants.

California strawberry consumption increased the abundance of gut microorganisms related to lean body weight, health and longevity in healthy subjects

It was our hypothesis that foods high in polyphenols and fiber have prebiotic activity. This human intervention study aimed to determine if daily consumption of freeze-dried California strawberry powder (SBP) leads to changes in the intestinal microbiota, fecal cholesterol and bile acid (BA) microbial metabolites. Fifteen healthy adults consumed a beige diet+26 g of SBP for 4 weeks, followed by 2 weeks of beige diet only. Stool samples were collected at 0, 4, and 6 weeks. Fecal microbiota was analyzed by 16S rRNA sequencing; fecal cholesterol, BA, and microbial metabolites by gas chromatography. Confirming compliance, urine concentration of pelargonidin, urolithin A glucuronide and dimethylellagic acid glucuronide were present after 4 weeks of SBP consumption. Daily SBP altered the abundance of 24 operational taxonomic units (OTUs). Comparing week 4 to baseline the most significant increases were observed for one OTU from Firmicutes\Clostridia\ Christensenellaceae\NA, one OTU from Firmicutes\ Clostridia\Mogibacteriacea\NA, one OTU from Verrucomicrobia\ Verrucomicrobiaceae\Akkermansia\Muciniphila, one OTU from Actinobacteria\ Bifidobacteriaceae\Bifidobacterium\NA, and one OTU from Bacteroidetes\Bacteroidia\ Bacteroidaceae\Bacteroides and decrease of one OTU from Proteobacteria\ Betaproteobacteria\Alcaligenaceae\Sutterella. Comparing week 4 to 6, we observed a reversal of the same OTUs from C Christensenellaceae, V muciniphilia and C Mogibacteriaceae. Fecal short chain fatty acids and most of the fecal markers including cholesterol, coprostanol, primary and secondary BAs were not changed significantly except for lithocholic acid, which was increased significantly at week 6 compared to baseline. In summary, SBP consumption increased the abundance of gut microorganisms related to lean body weight, health and longevity, and increased fecal lithocholic acid at week 6 in healthy study participants.

Pomegranate Metabolites Impact Tryptophan Metabolism in Humans and Mice

BACKGROUND

We showed that pomegranate juice (PomJ) can help to maintain memory in adults aged >50 y. The mechanism for this effect is unknown, but might involve Trp and its metabolites, which are important in brain function.

OBJECTIVES

We aimed to test the hypothesis that PomJ and its metabolites ellagic acid (EA) and urolithin A (UA) affect Trp metabolism.

METHODS

Stool and plasma from a cohort [11 PomJ, 9 placebo drink (PL)] of subjects enrolled in our double-blind, placebo-controlled trial (NCT02093130) were collected at baseline and after 1 y of PomJ or PL consumption. In a mouse study, cecum and serum were collected from DBA/2J mice receiving 8 wk of dietary 0.1% EA or UA supplementation. Trp metabolites and intestinal microbiota were analyzed by LC-MS and 16S rRNA gene sequencing, respectively.

RESULTS

In the human study, the change in the plasma Trp metabolite indole propionate (IPA) over 1 y was significantly different between PomJ and PL groups (P = 0.03). In serum of experimental mice, we observed a 230% increase of IPA by EA but not UA, a 54% increase of indole sulfate by UA but not EA, and 43% and 34% decreases of kynurenine (KYN) by EA and UA, respectively. In cecum, there was a 32% decrease of Trp by UA but not EA, and an 86% decrease of KYN by EA but not UA (P < 0.05). The abundance of 2 genera, Shigella and Catenibacterium, was reduced by PomJ in humans as well as by UA in mice, and their abundance was negatively associated with blood IPA in humans and mice (P < 0.05).

CONCLUSIONS

These results suggest a novel mechanism involving the regulation of host and microbial Trp metabolism that might contribute to the health benefits of ellagitannins and EA-enriched food, such as PomJ.

Ellagic Acid and Its Microbial Metabolite Urolithin A Alleviate Diet-Induced Insulin Resistance in Mice

SCOPE

This work aims at evaluating the effect of dietary ellagic acid (EA) and its microbial metabolite urolithin A (UA) on glucose metabolism and insulin resistance (IR) in mice with diet-induced IR.

METHODS AND RESULTS

DBA2J mice are fed a high fat/high sucrose diet (HF/HS) for 8 weeks to induce IR and then 0.1% EA, UA, or EA and UA (EA+UA) are added to the HF/HS-diet for another 8 weeks. UA significantly decreases fasting glucose and increases adiponectin compared with HF/HS-controls. During intraperitoneal insulin tolerance test, EA+UA significantly improve insulin-mediated glucose lowering effects at 15 and 120 min and reduce blood triglycerides compared with HF/HS-controls. Serum free fatty acids are significantly decreased by EA, UA, and EA+UA. Differential expression of genes related to mitochondrial function by EA, UA, and EA+UA in liver and skeletal muscle is observed. Primary hepatocytes from IR-mice have higher proton leak, basal and ATP-linked oxygen consumption rates compared with healthy controls. EA and EA+UA but not UA reduce the proton leak in hepatocytes from IR-mice.

CONCLUSION

EA and UA induce different metabolic benefits in IR mice. The effects of EA and UA on mitochondrial function suggest a potentially novel mechanism modulating metabolism.

California Strawberry Consumption Alters Gut Microbiome in Healthy Participants: A Pilot Study

Objectives

Based on the polyphenol and fiber content of strawberries (SB), it was our hypothesis that daily consumption of California strawberries will lead to changes in the composition of the intestinal microbiota, and concentration of fecal cholesterol and bile acid (BA) microbial metabolites.

Methods

We performed a randomized, double blind, parallel design intervention study. 28 healthy adults were randomized to either daily consumption of 26 g of SB powder (2 servings of fresh SB) or placebo (PL) powder for 4 wks. Stool samples were collected at baseline (BL), 4 and 6 wks (2 wks no SB/PL). Fecal microbiota was analyzed by 16S rDNA sequencing of the V4 region; fecal cholesterol, coprostanol, cholestanol, cholic acid (primary BA), chenodeoxycholic acid (primary BA), deoxycholic acid (2ndBA), lithocholic acid (2ndBA) by gas chromatography, serum cholesterol, triglyceride by colorimetric assay and serum pelargonidin glucuronide (PG) by high performance liquid chromatography.

Results

Serum PG, a SB anthocyanin, was found in all participants in the SB group. Two participants in the PL group showed serum PG and were excluded from the analyses. Daily SB increased the abundance of Christensenellaceae, Bifidobacteriaceae, Verrucomicrobiaceae and multiple members of the Lachnospiraceae, Ruminococcaceae family, and decreased significantly Alcaligenaceae/Sutterella comparing BL to wk4. Comparing the change from BL to wk4 between the SB and PL group, we found increased abundance of Alcaligenaceae/Sutterella and several members of the Clostridia class including Lachnopsiraceae and Ruminococcaceae and a decrease in Clostridiaceae. Comparing wk 4 to wk 6, we observed a reversal of Clostridiales/Christensenellaceae, Verrucomicrobiaceae, and Alcaligenaceae/Sutterella. No effects on alpha and beta diversity were observed. No significant difference in serum and fecal cholesterol, BA and bacterial metabolites was observed between SB and PL groups. Five participants did not form coprostanol. Comparing coprostanol producers to non-producers at baseline showed that most differences were observed in the Lachnospiraceae, Ruminococcaceae and Bacteroidaceae families.

Conclusions

SB consumption altered the gut microbiota, which was partially reversed after 2 wks of customary diet without SB.

Funding Sources

California Strawberry Commission.

Effect of Dietary XOS Supplementation on Systemic Amino Acid Homeostasis

Objectives

Systemic amino acid (AA) levels are tightly regulated. Homeostasis of certain AAs, such as branched chain AAs (BCAAs), and aromatic AAs are not only associated with impaired glucose control but also important determinants of mood. The health benefits of dietary xylooligosaccharides (XOS) in glucose control have been published. In addition, XOS consumption was reported to increase participant-reported vitality and happiness. Therefore, we hypothesized that dietary XOS supplementation induce changes of AA homeostasis, which contributes to its metabolic and mood benefit.

Methods

Male db/db BSK mice and their respective lean control db/m BSK mice were used in this study. Mice at age 7 wk were randomized into three groups and fed AIN93M, AIN93M + 2%−, or 7%-XOS (w/w) for 8 weeks (n = 8–10/group). At the end of the intervention, fasting serum samples were collected and processed for glucose, insulin, AA analysis.

Results

db/db mice developed obesity, hyperglycemia and hyperinsulinemia compared to db/m mice. We did not detect difference in serum BCAAs and aromatic AAs, including phenylalanine (phe), tryptophan (Trp) and tyrosine (Tyr) between db/db and db/m mice. Serum arginine (Arg), proline (Pro) and methionine (Met) were significantly lower in db/db compared db/m. Dietary XOS supplementation (2 and 7%) did not change body weight and fat depots in db/m and db/db mice. Fasting blood glucose, Met and Pro levels were significantly reduced by 7% XOS in db/m not db/db mice. XOS did not change any other AAs in either db/db or db/m mice. Serum Trp microbial metabolites indole acetate (IAA) was significantly higher while indole propionate (IPA) was lower in db/db mice compared to db/m mice. XOS (both 2 and 7%) decreased IAA in both db/m and db/db mice, while 2% XOS increased IPA only in db/db mice. Tyr was decreased by 7% XOS in db/m mice but not db/db mice, while Tyr metabolite, p-cresol sulfate, was reduced by 2% XOS in db/db mice only.

Conclusions

Our data indicate interactions between dietary XOS and Leptin R genotype/or host metabolic status on glucose control and systemic AA homeostasis. The mechanism of how dietary XOS intake modulate AA homeostasis needs further investigation.

Funding Sources

This project was supported by NIH-R01 and Center for Human Nutrition.

The Glycemic Effects of Pomegranate Juice

Objectives

We recently showed that a single dose of pomegranate juice (PomJ) intake reduced fasting glucose and increased insulin in young healthy subjects. Our study aims to determine the responses of blood glucose as well as principle hormones involved in glucose homeostasis (insulin, C-peptide, glucagon and gastric inhibitory polypeptide (GIP)) after consuming a single dose of 8 oz PomJ, glucose/fructose dissolved in water compared to water in healthy subjects.

Methods

21 Healthy, normal weight individuals (BMI of &gt;18 to 26.9 kg/m2, fasting serum glucose &lt; 100 mg/dL) were recruited. Volunteers were randomly assigned to take a single dose of 8 oz of water, PomJ, or water with 18.6 g of glucose + 18.3 g of fructose to match PomJ sugar content, followed by 1-week wash out, and crossover to other interventions in a random order. Fasting blood was collected before, and at 15, 30, 60, 90, 120, 150 and 180 minutes (min) after the drink. Serum glucose was measured enzymatically (Cayman) and insulin, C-peptide, glucagon, and GIP were analyzed using the multiplex human cytokine panel (Millipore).

Results

21 healthy volunteers were divided in to 2 groups according to the fasting serum insulin levels: healthy subjects with low fasting serum insulin ≤995 pg/mL (LFSI, n = 12) and healthy subjects with high fasting serum insulin &gt;995 pg/mL (HFSI, n = 9). In all subjects, water intake did not change the levels of glucose and hormonal markers. In LFSI subjects, significant lower glucose at 15 min and GIP at both 15 min and 30 min were observed after PomJ compared to sugar water intake. The area under the curve of serum GIP from LFSI volunteers consuming PomJ was lower compared to sugar water. The levels of insulin, C-peptides and glucagon in response to PomJ and sugar water intake were similar. In HFSI subjects, levels of glucose, C-peptide and glucagon in response to PomJ and sugar water intake were similar. Significant higher insulin at 15 and 30 min, and lower GIP at both 15, 30 and 60 min were observed after PomJ compared to sugar water intake.

Conclusions

Compared to identical amount of sugar in water, lower glucose response was observed after Pom J in LFSI subjects while higher insulin level and decreased GIP level in HFSI subjects without any difference in glucose. Our data suggest that components in PomJ likely regulate individuals’ glucose metabolism.

Funding Sources

Center for Human Nutrition.

Prospective randomized trial evaluating blood and prostate tissue concentrations of green tea polyphenols and quercetin in men with prostate cancer

We evaluated if chronic consumption of quercetin (Q) with green tea extract (GTE) enhances the bioavailability of GT polyphenols (GTPs) and reduces methylation activity as previously observed in mouse xenograft tumors. In this prospective, randomized, parallel design, placebo controlled study, thirty-one men with prostate cancer consumed daily 1 gram of GTE (830 mg of GTP) with 800 mg of Q (GT + Q) or placebo (GT + PL) for four weeks before prostatectomy. First morning voided urine was collected at baseline, 3 weeks and the day of surgery, and prostate tissue on the day of surgery. In week 3, plasma concentration of GTPs and Q was measured in blood collected before and 2 hours after the morning dose. Prostate tissue epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) were detected in 67 and 93% of participants in the GT + Q group and 75 and 94% of participants in the GT + PL group. Q was increased 14-fold, 12-fold and 4.5-fold in plasma, urine, and prostate tissue, respectively, in the GT + Q compared to the GT + PL-group. There was a trend for decreased EGC levels in urine collected prior to prostatectomy in the GT + Q compared to GT + PL-group (p = 0.053). Plasma epigallocatechin (EGC) showed a trend to increase (p = 0.066) two hours after capsule intake in the GT + Q vs. the GT + PL-group. There was no significant difference between the groups in GTP content or methylation activity in prostate tissue or RBCs. No liver toxicity was observed. Although our findings are suggestive, further studies are warranted evaluating if Q alters GTP metabolism.

Bioavailability and bioactivity of free ellagic acid compared to pomegranate juice

Pomegranates are an excellent source of ellagic acid (EA), ellagitannins (ETs), anthocyanins and other phytochemicals. The health benefits of pomegranate (Pom) have been mainly related to its EA and ET content. The objective of the present study was to determine EA bioavailability and bioactivity from different sources such as pure/free or natural form (PomJ). This was a cross-over study with healthy volunteers consuming one dose of EA dietary supplement (500 mg free EA) vs. one serving of PomJ (237 mL, ∼120 mg of EA) in a random order. Our data showed that there was no difference in plasma EA concentration between PomJ and EA intake; however, urinary dimethylellagic acid glucuronide (DMEAG), normalized to creatinine, was significantly higher after the consumption of PomJ compared to EA. Plasma insulin at 1 h increased after PomJ consumption compared to the baseline while decreased after EA consumption compared to the baseline. Plasma glucose decreased below the baseline 2 h after the consumption of PomJ but not EA. Plasma leptin was significantly decreased at 1 and 2 h after PomJ and EA consumption. Plasma MCP1 decreased only after PomJ but not after pure EA consumption. To conclude, one serving of PomJ provided the same level of EA in blood, while the increase in phase II metabolism of EA and an acute suppression of plasma MCP1 were only observed after PomJ consumption, suggesting that other constituents present in PomJ, in addition to EA, are bioactive and likely play a role in regulating EA phase II metabolism.

Randomized placebo-controlled study of the memory effects of pomegranate juice in middle-aged and older adults

BACKGROUND

Antioxidant nutrients such as the polyphenols in pomegranate juice may prevent neuronal damage from the free radicals produced during normal metabolism. Previous research in animals and a short-term clinical trial in middle-aged and older adults support the potential memory benefits of pomegranate juice; however, the long-term effects of pomegranate juice consumption on cognition have not been studied.

OBJECTIVE

In this study, we investigated the long-term effect of pomegranate juice on memory in nondemented middle-aged and older adults.

METHODS

We performed a 12-month, randomized, double-blind, placebo-controlled trial of pomegranate juice in middle-aged and older adults. Two hundred and sixty-one subjects (aged 50-75 y) were randomly assigned to consume pomegranate juice [8 oz (236.5 mL) per day] or a placebo drink (8 oz, matched constituents of pomegranate juice except for pomegranate polyphenols). Memory measures [Brief Visuospatial Memory Test-Revised (BVMT-R) and Buschke Selective Reminding Test (SRT)] were assessed at 6 and 12 mo and analyzed using a mixed-effects general linear model.

RESULTS

Twenty-eight subjects in the pomegranate juice group and 33 subjects in the placebo group dropped out before completing the study. Baseline variables in the 98 pomegranate juice and 102 placebo group subjects who completed the study did not differ significantly. Group by time interaction was statistically significant for BVMT-R Learning (F[2, 257]= 5.90, P = 0.003; between-group effect size [ES] = 0.45): the change within the pomegranate group was not significant (ES = 0.15), whereas the placebo group showed a significant decline (ES = -0.35). Changes in the other BVMT-R scores as well as the SRT measures were not significantly different between groups.

CONCLUSIONS

Daily consumption of pomegranate juice may stabilize the ability to learn visual information over a 12-mo period. This trial was registered at clinicaltrials.gov as NCT02093130.

Pomegranate Juice and Extract Consumption Increases the Resistance to UVB-induced Erythema and Changes the Skin Microbiome in Healthy Women: a Randomized Controlled Trial

In vitro and animal studies have demonstrated that topical application and oral consumption of pomegranate reduces UVB-induced skin damage. We therefore investigated if oral pomegranate consumption will reduce photodamage from UVB irradiation and alter the composition of the skin microbiota in a randomized controlled, parallel, three-arm, open label study. Seventy-four female participants (30–45 years) with Fitzpatrick skin type II-IV were randomly assigned (1:1:1) to 1000 mg of pomegranate extract (PomX), 8 oz of pomegranate juice (PomJ) or placebo for 12 weeks. Minimal erythema dose (MED) and melanin index were determined using a cutometer (mexameter probe). Skin microbiota was determined using 16S rRNA sequencing. The MED was significantly increased in the PomX and PomJ group compared to placebo. There was no significant difference on phylum, but on family and genus level bacterial composition of skin samples collected at baseline and after 12 week intervention showed significant differences between PomJ, PomX and placebo. Members of the Methylobacteriaceae family contain pigments absorbing UV irradiation and might contribute to UVB skin protection. However, we were not able to establish a direct correlation between increased MED and bacterial abundance. In summary daily oral pomegranate consumption may lead to enhanced protection from UV photodamage.

Hass Avocado Inclusion in a Weight-Loss Diet Supported Weight Loss and Altered Gut Microbiota: A 12-Week Randomized, Parallel-Controlled Trial

BACKGROUND

Avocados contain fiber, lutein, and vitamin E, and they are a rich source of MUFAs. The effect of including an avocado daily as part of a hypocaloric weight-loss diet on weight loss is not known.

OBJECTIVE

The aim of this study was to determine the effect of daily avocado consumption as part of a hypocaloric diet on weight loss, body composition, satiety, biomarkers of inflammation, and intestinal microbiota composition.

METHODS

In this randomized, parallel-controlled, open-label, 2-arm intervention study, 51 healthy overweight/obese women and men were assigned to a hypocaloric diet with 1 Hass avocado daily (AVO; n = 24) or a hypocaloric diet (CTRL; n = 27) without daily avocado for 12 wk. Serum markers and intestinal microbiota were analyzed at baseline and week 12.

RESULTS

Both groups experienced significant weight loss, decrease in BMI (in kg/m2), total body fat, and visceral adipose tissue, respectively (AVO: -2.3 ± 2 kg, -0.8 ± 0.8, -1.1% ± 2%, and -81.2 ± 118 g; CTRL: -2.6 ± 3.6 kg, -0.9 ± 1, -1.5% ± 2%, and -87.4 ± 216 g). We observed a significant decrease in serum glucose over time in the control group compared with the AVO group. There was no change between the groups in serum triglyceride, but a significant decrease from baseline to 12 wk was observed in the AVO group. Serum hepatic growth factor (HGF) and relative proportion of bacterial phyla (Firmicutes and Bacteroidetes), family (Bacteroidaceae and Erysipelotrichaceae), and genus (Bacteroides, Clostridium, Methanosphaera, and Candidatus Soleaferrea) were significantly altered in the AVO group compared with the CTRL group. A trend to decrease in serum inflammatory factors IL-1β (P = 0.07) and C-reactive protein (P = 0.074) was observed in the AVO group compared with CTRL.

CONCLUSIONS

Daily Hass avocado consumption as part of a hypocaloric diet supported weight loss, a decrease in serum HGF, and an increase in the abundance of bacteria involved in plant polysaccharide fermentation. This trial was registered at clinicaltrials.gov as NCT02953158.

Mixed Spices at Culinary Doses Have Prebiotic Effects in Healthy Adults: A Pilot Study

Spices were used as food preservatives prior to the advent of refrigeration, suggesting the possibility of effects on microbiota. Previous studies have shown prebiotic activities in animals and in vitro, but there has not been a demonstration of prebiotic or postbiotic effects at culinary doses in humans. In this randomized placebo-controlled study, we determined in twenty-nine healthy adults the effects on the gut microbiota of the consumption daily of capsules containing 5 g of mixed spices at culinary doses by comparison to a matched control group consuming a maltodextrin placebo capsule. The 16S ribosomal RNA sequencing data were used for microbial characterization. Spice consumption resulted in a significant reduction in Firmicutes abundance (p < 0.033) and a trend of enrichment in Bacteroidetes (p < 0.097) compared to placebo group. Twenty-six operational taxonomic units (OTUs) were different between the spice and placebo groups after intervention. Furthermore, there was a significant negative correlation between fecal short-chain fatty acid propionate concentration and Firmicutes abundance in spice intervention group (p < 0.04). The production of individual fecal short-chain fatty acid was not significantly changed by spice consumption in this study. Mixed spices consumption significantly modified gut microbiota, suggesting a prebiotic effect of spice consumption at culinary doses.

Ellagic Acid Bioavailability and Metabolism After Single Dose Consumption of Pure Ellagic Acid versus Pomegranate Juice (P06-031-19)

Objectives

In the GI tract, Pomegranates (Pom) ellagitannins undergo hydrolysis to ellagic acid (EA) and are further metabolized into urolithins by the gut microbiota. Both EA and UA have significant health benefits. EA is also available as dietary supplement. We aimed to compare the bioavailability of EA and its biotransformation to UA between pure EA and Pom juice (PomJ).

Methods

17 healthy male participants were randomly assigned to take a single dose of 8 oz of PomJ or 500 mg of EA, followed by 2-week washout, and crossover to the other intervention. We collected blood prior and 1 and 2 h after consumption of EA or PomJ and urine for 24hours. Plasma concentration of EA was measured using HPLC. Urinary EA metabolites (DMEAG and UAG) were determined by LC/MS and normalized to urine creatinine levels. Circulating MCP1, insulin and leptin were analyzed using the multiplex human cytokine panel (Millipore).

Results

There was no difference in plasma EA concentration after administration of PomJ versus 500 mg EA. Urinary DMEAG, normalized to creatinine, was significantly higher after PomJ compared to EA intake (PomJ: 0.11 + 0.02; EA: 0.05 + 0.01 µg/mg; P < 0.05). Urinary UAG was present in 13 participants and 4 out of 17 subjects did not have the ability to convert EA to UA after consumption of either pure EA vs. PomJ. Blood glucose at 2 hrs decreased −5.53% ± 1.61% (p = 0.01) and insulin at 1 hr increased 95.74% ± 37.44% (p < 0.05) after PomJ consumption compared to baseline. Blood MCP1 decreased −15.51% ± 6.11% (p < 0.05) 2 hrs after PomJ, and leptin was significantly decreased (PomJ: −17.13% ± 4.64% (p < 0.00); EA: −18.80% ± 2.93% (p < 0.00)) 2 hrs after PomJ and EA consumption.

Conclusions

8 oz of PomJ provides an equivalent source of EA and microbial mediated biotransformation of EA to UA compared to 500 mg EA supplement. However, an increase in phase II metabolism of EA and acute effect on plasma MCP1 was only observed following PomJ consumption.

Funding Sources

Center for Human Nutrition, David Geffen School of Medicine at UCLA, Los Angeles.

Effect of Mixed Nuts on Body Weight and Composition, and Gut Microbiome (P08-054-19)

Objectives

This study was designed to assess the effects of mixed nut consumption on body weight and composition, and gut microbiome in obese individuals. Primary outcome was change in body weight and composition. Secondary outcomes include gut microbiome composition, inflammatory markers, and plasma lipids.

Methods

The reported results are from an interim analysis (n = 50) of a randomized, placebo controlled, parallel study. Total enrollment target is 154 overweight/obese subjects (BMI 27–35 kg/m2). Participants were randomly assigned to consume either 1.5oz mixed tree nuts or pretzels with equal calorie content daily for 24 weeks. The study included a 12-week weight loss phase (500 kcal per day less than total daily energy expenditure), followed by a 12-week weight maintenance phase. Body composition, fasting blood, and stool samples were collected at baseline, week 12 and 24. Body composition, and vitals were analyzed, whereas plasma lipid profile, fecal microbiome, and microbiome metabolites analysis is still pending.

Results

At week 12, subjects from both the pretzel (n = 15, 10 dropouts; P = 0.009) and nut group (n = 22, 3 dropouts; P = 0.038) lost significant amount of weight. The trend of weight changes did not differ between groups (P = 0.530). Subjects from both groups were able to sustain weight loss through 24 weeks (pretzel: 81.43 ± 3.85 kg at baseline vs. 79.43 ± 4.08 kg at week 24, P = 0.028; nut: 84.26 ± 3.78 kg at baseline vs. 82.38 ± 3.72 kg at week 24, P = 0.026). At week 12, fat mass in both groups was significantly decreased (pretzel: P = 0.002; nut: P = 0.012). The trend of fat changes did not differ between groups (P = 0.547). Subjects from both groups were able to sustain fat loss through 24 weeks (pretzel: 30.84 ± 1.75 kg at baseline vs. 29.25 ± 2.12 kg at week 24, P = 0.024; nut: 31.51 ± 1.56 kg vs 30.21 ± 1.81 kg at week 24, P = 0.04). Muscle mass, and blood pressure were not significantly different between both groups.

Conclusions

Our data suggested that tree nuts could be consumed as part of a healthy weight loss meal plan without concern of causing weight gain. Further analysis of the remaining samples is needed to confirm results. Due to higher dropouts in the pretzel group, future intention-to-treat analysis is also needed to eliminate bias.

Funding Sources

This study is supported by the International Tree Nut Council.

Effects of Cinnamon Spice on Postprandial Plasma Levels of Glucose and Insulin in Healthy Participant with Normal Weight (FS15-04-19)

Objectives

The objective of this study is to investigate the effect of one time intake of cinnamon spice on the postprandial glucose tolerance and insulin secretion following consumption of a high glycemic index meal in normal weight and glucose tolerance individuals.

Methods

Sixteen healthy controls (BMI = 18.5–24.9 kg/m2 and fasting blood glucose (BG) < 100 mg/dL) aging 20–50 years, who typically consume a low fiber/polyphenol diet (beige diet) were recruited for this study. Recruitment of overweight/obese, prediabetic participants is not completed (no data presented). Participants consume a typical American breakfast containing 50 g of carbohydrates (1/3 cup of oatmeal and 1 cup 2% milk) with or without cinnamon (6 g) followed by 1-week washout and crossover to the opposite intervention. The blood samples were taken at fasting state and at 30, 60, 90, 120, 150 and 180 minutes after the meal. The main outcome measures included BG and insulin. The secondary outcome measures were C-peptide and glucagon. Cinnamon spice (Indonesia) was purchased at the local grocery store (McCormick®) and contains 3.9% proanthocyanin. The statistical significance was set at P < 0.05 using SPSS.

Results

Consumingcinnamon spice with the oatmeal significantly decreased the rate of glucose change from fasting state at 60 and 90 minutes after the meal by 37% and 31%, respectively. The peak postprandial BG and the areas under the curve (AUC) of glucose were also lowered by cinnamon compared to oatmeal alone but did not reach the significant levels. There was a trend towards significant decrease (21%, P = 0.08) in plasma insulin concentrations and a significant decrease in plasma C-peptide levels 30 minutes after ingestion of the meal with cinnamon. Cinnamon ingestion compared to oatmeal alone also significantly decreased plasma glucagon levels at 90 minutes after the meal test.

Conclusions

Our results suggest that one time intake of cinnamon spice lowers the mean rate of glucose change following a high glycemic index meal in healthy individuals. Cinnamon also decreased plasma levels of insulin, C-peptide, and glucagon.

Funding Sources

UCLA Center for Human Nutrition.

Effect of Pomegranate Juice Consumption on Plasma Indole Propionic Acid, a Bacterial-Derived Tryptophan Metabolite (P20-003-19)

Objectives

The gut microbiota produces numerous metabolites from dietary nutrients that can circulate systemically and influence the host physiology. Bacterial enzymes convert dietary L-tryptophan (Trp) to indole, from which several metabolites can be formed by mammalian and bacterial enzymes. The bacterial metabolite indole propionic acid (IPA) is anti-inflammatory, neuroprotective and has been linked to a lower risk of type 2 diabetes. Little is known about which bacteria are responsible for IPA formation. Pomegranates (Pom) are excellent sources of ellagitannins (ET) and ellagic acid (EA) with prebiotic function. Therefore, it was our hypothesis that long-term Pom consumption will change bacterial Trp metabolite formation.

Methods

We performed a 12-month, randomized, double-blind, placebo-controlled trial of pomegranate juice in middle-aged and older, healthy adults. Nineteen subjects (ages 50–60) were randomized to consume 8 oz of pomegranate juice (the Wonderful Company, LLC) (N = 11) or placebo drink (N = 8) every day. The placebo drink contained high fructose corn syrup, Pom essence and flavor and FD&C Red#40, Blue#1. Stool samples were collected at baseline and after 1 year of Pom J consumption. Bacterial composition was determined using 16S rRNA microbiome sequencing. Plasma IPA concentrations were determined by HPLC. Correlation between fecal bacterial content and plasma IPA was evaluated in all samples using Spearman's analysis.

Results

The IPA was significantly reduced in the placebo group (P = 0.017), while there was no change in the Pom J group (P = 0.458). The change in plasma IPA during one year of Pom J compared to placebo drink consumption was significantly different (P = 0.028). At 12 months, plasma IPA concentration was significantly positively correlated with the relative proportion of Roseburia (0.57), Lachnospira (0.53) in the phylum Firmicutes; Sutterella (0.63) in the phylum Proteobacterium and Collinsella (0.46) in the phylum Actinobacteria. A significant negative correlation was observed with the relative proportion of Campylobacteraceae (−0.46).

Conclusions

Formation of IPA associated with a microbial profile supported by Pom J consumption might contribute to the cardiovascular health benefits of Pom.

Funding Sources

Supported by Center for Human Nutrition, UCLA.

Effects of branched-chain amino acids on glucose metabolism in obese, prediabetic men and women: a randomized, crossover study

BACKGROUND

Recent studies have shown that circulating branched-chain amino acids (BCAAs) are elevated in obese, insulin-resistant individuals. However, it is not known if supplementation of additional BCAAs will further impair glucose metabolism.

OBJECTIVES

The aim of this pilot study was to determine the effects of BCAA supplementation on glucose metabolism in obese, prediabetic individuals.

METHODS

This is a randomized crossover study involving 12 obese individuals with prediabetes. Participants were randomly assigned to receive a daily supplement containing either 20 g BCAA or protein low in BCAAs for 4 wk with a 2-wk washout in between. At each visit, an oral-glucose-tolerance test (OGTT) was performed. Collected blood samples were used to measure glucose, insulin, and insulin resistance-associated biomarkers.

RESULTS

BCAA supplementation tended to decrease the plasma glucose area under the curve (AUC) measured by the OGTT (AUC percentage change from supplementation baseline, BCAA: -3.3% ± 3%; low-BCAA: 10.0% ± 6%; P = 0.08). However, BCAA supplementation did not affect plasma insulin during OGTT challenge (BCAA: -3.9% ± 8%; low-BCAA: 14.8% ± 10%; P = 0.28). The plasma concentrations of nerve growth factor (BCAA: 4.0 ± 1 pg/mL; low-BCAA: 5.7 ± 1 pg/mL; P = 0.01) and monocyte chemoattractant protein-1 (BCAA: -0.4% ± 9%; low-BCAA: 29.0% ± 18%; P = 0.02) were significantly lowered by BCAA supplementation compared to low-BCAA control. Plasma interleukin 1β was significantly elevated by BCAA supplementation (BCAA: 231.4% ± 187%; low-BCAA: 20.6% ± 33%; P = 0.05). BCAA supplementation did not affect the circulating concentrations of the BCAAs leucine (BCAA: 9.0% ± 12%; low-BCAA: 9.2% ± 11%), valine (BCAA: 9.1% ± 11%; low-BCAA: 12.0% ± 13%), or isoleucine (BCAA: 2.5% ± 11%; low-BCAA: 7.3% ± 11%).

CONCLUSIONS

Our data suggest that BCAA supplementation did not impair glucose metabolism in obese, prediabetic subjects. Further studies are needed to confirm the results seen in the present study. This study was registered at clinicaltrials.gov as NCT03715010.

Pomegranate juice and extract extended lifespan and reduced intestinal fat deposition in Caenorhabditis elegans

Pomegranate juice with a high content of polyphenols, pomegranate extract, ellagic acid, and urolithin A, have anti-oxidant and anti-obesity effects in humans. Pomegranate juice extends lifespan of Drosophila melanogaster. Caenorhabditis elegans (C. elegans) (n = 6) compared to the control group in each treatment, lifespan was increased by pomegranate juice in wild type (N2, 56 %, P < 0.001) and daf-16 mutant (daf-16(mgDf50)I) (18 %, P = 0.00012), by pomegranate extract in N2 (28 %, P = 0.00004) and in daf-16(mgDf50)I (10 %, P < 0.05), or by ellagic acid (11 %, P < 0.05). Pomegranate juice reduced intestinal fat deposition (IFD) in C. elegans (n = 10) N2 (-68 %, P = 0.0003) or in the daf-16(mgDf50)I (-33 %, P = 0.0034). The intestinal fat deposition was increased by pomegranate extract in N2 (137 %, P < 0.0138) and in daf-16(mgDf50)I (26 %, P = 0.0225), by ellagic acid in N2 (66 %, P < 0.0001) and in daf-16(mgDf50)I (74 %, P < 0.0001), or by urolithin A in N2 (57 %, P = 0.0039) and in daf-16(mgDf50)I (43 %, P = 0.0001). These effects were partially mediated by the daf-16 pathway. The data may offer insights to human aging and obesity due to homology with C. elegans.

Effects of Prebiotic Fiber Xylooligosaccharide in Adenine-Induced Nephropathy in Mice

SCOPE

This study evaluates the effect of the prebiotic fiber xylooligosaccharide (XOS) on kidney function and gut microbiome in mice with adenine-induced chronic kidney disease (CKD).

METHOD AND RESULTS

Mice are fed the control diet containing adenine for 3 weeks to induce CKD and are switched to XOS supplemented (2 or 7%) or control diets for another 3 weeks. Mice with CKD exhibit increased blood urea nitrogen (BUN), creatinine, and kidney histopathology. XOS significantly reverses kidney injuries in CKD mice. Analysis of cecum microbiota reveales that adenine-induced CKD does not change alpha diversity, and XOS induces a decrease of alpha diversity in control mice and mice with CKD. Beta diversity analysis shows significant clustering according to experimental groups. Six out of the nine bacterial genera enriched in CKD are significantly reduced with XOS intervention. Furthermore, XOS increases cecal short-chain fatty acid (SCFA) production in both control and CKD mice. Cecal SCFAs and blood propionate are negatively correlated with BUN. XOS also decreases blood p-cresol sulfate in CKD mice, likely resulting from altered microbial tyrosine metabolism.

CONCLUSION

These results show that XOS intervention improves kidney function in mice with CKD, and is associated with profound changes in microbial composition and metabolism.

Memory and Brain Amyloid and Tau Effects of a Bioavailable Form of Curcumin in Non-Demented Adults: A Double-Blind, Placebo-Controlled 18-Month Trial

OBJECTIVE

Because curcumin's anti-inflammatory properties may protect the brain from neurodegeneration, we studied its effect on memory in non-demented adults and explored its impact on brain amyloid and tau accumulation using 2-(1-{6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile positron emission tomography (FDDNP-PET).

METHODS

Forty subjects (age 51-84 years) were randomized to a bioavailable form of curcumin (Theracurmin® containing 90 mg of curcumin twice daily [N = 21]) or placebo (N = 19) for 18 months. Primary outcomes were verbal (Buschke Selective Reminding Test [SRT]) and visual (Brief Visual Memory Test-Revised [BVMT-R]) memory, and attention (Trail Making A) was a secondary outcome. FDDNP-PET signals (15 curcumin, 15 placebo) were determined in amygdala, hypothalamus, medial and lateral temporal, posterior cingulate, parietal, frontal, and motor (reference) regions. Mixed effects general linear models controlling for age and education, and effect sizes (ES; Cohen's d) were estimated.

RESULTS

SRT Consistent Long-Term Retrieval improved with curcumin (ES = 0.63, p = 0.002) but not with placebo (ES = 0.06, p = 0.8; between-group: ES = 0.68, p = 0.05). Curcumin also improved SRT Total (ES = 0.53, p = 0.002), visual memory (BVMT-R Recall: ES = 0.50, p = 0.01; BVMT-R Delay: ES = 0.51, p = 0.006), and attention (ES = 0.96, p < 0.0001) compared with placebo (ES = 0.28, p = 0.1; between-group: ES = 0.67, p = 0.04). FDDNP binding decreased significantly in the amygdala with curcumin (ES = -0.41, p = 0.04) compared with placebo (ES = 0.08, p = 0.6; between-group: ES = 0.48, p = 0.07). In the hypothalamus, FDDNP binding did not change with curcumin (ES = -0.30, p = 0.2), but increased with placebo (ES = 0.26, p = 0.05; between-group: ES = 0.55, p = 0.02).

CONCLUSIONS

Daily oral Theracurmin may lead to improved memory and attention in non-demented adults. The FDDNP-PET findings suggest that symptom benefits are associated with decreases in amyloid and tau accumulation in brain regions modulating mood and memory.

Proceedings of the 11th Congress of the International Society of Nutrigenetics and Nutrigenomics (ISNN 2017)

The International Society of Nutrigenetics and Nutrigenomics (ISNN) held its 11th annual Congress in Los Angeles, California, between September 16 and 19, 2017. In addition to 2 keynote lectures, 4 plenary sessions included presentations by internationally renowned speakers on cutting-edge areas of research and new discoveries in genetics/genomics, the microbiome, and nutrition. Scientific topics included multi-omics approaches; diet and the microbiome; cancer, longevity, and metabolism; moving the field forward; and translational/educational aspects and the future of medicine. There was also an accepted oral abstracts session designed specifically to provide young investigators and trainees with the opportunity to present their work, as well as a session focused on industry-academic partnerships, which included a roundtable discussion afterwards. Overall, the 11th ISNN Congress was an exciting and intellectually stimulating meeting focused on understanding the impact of biological interactions between genes and nutrients on health and disease. These efforts continued the decade-long tradition of the annual ISNN Congress to provide an interdisciplinary platform for scientists from various disciplines to discuss research ideas and advance the fields of nutrigenetics and nutrigenomics.

Decaffeinated green and black tea polyphenols decrease weight gain and alter microbiome populations and function in diet-induced obese mice

PURPOSE

Decaffeinated green tea (GT) and black tea (BT) polyphenols inhibit weight gain in mice fed an obesogenic diet. Since the intestinal microflora is an important contributor to obesity, it was the objective of this study to determine whether the intestinal microflora plays a role in the anti-obesogenic effect of GT and BT.

METHODS

C57BL/6J mice were fed a high-fat/high-sucrose diet (HF/HS, 32% energy from fat; 25% energy from sucrose) or the same diet supplemented with 0.25% GTP or BTP or a low-fat/high-sucrose (LF/HS, 10.6% energy from fat, 25% energy from sucrose) diet for 4 weeks. Bacterial composition was assessed by MiSeq sequencing of the 16S rRNA gene.

RESULTS

GTP and BTP diets resulted in a decrease of cecum Firmicutes and increase in Bacteroidetes. The relative proportions of Blautia, Bryantella, Collinsella, Lactobacillus, Marvinbryantia, Turicibacter, Barnesiella, and Parabacteroides were significantly correlated with weight loss induced by tea extracts. BTP increased the relative proportion of Pseudobutyrivibrio and intestinal formation of short-chain fatty acids (SCFA) analyzed by gas chromatography. Cecum propionic acid content was significantly correlated with the relative proportion of Pseudobutyrivibrio. GTP and BTP induced a significant increase in hepatic 5'adenosylmonophosphate-activated protein kinase (AMPK) phosphorylation by 70 and 289%, respectively (P < 0.05) determined by Western blot.

CONCLUSION

In summary, both BTP and GTP induced weight loss in association with alteration of the microbiota and increased hepatic AMPK phosphorylation. We hypothesize that BTP increased pAMPK through increased intestinal SCFA production, while GTPs increased hepatic AMPK through GTP present in the liver.

Prebiotic Potential and Chemical Composition of Seven Culinary Spice Extracts

The objective of this study was to investigate prebiotic potential, chemical composition, and antioxidant capacity of spice extracts. Seven culinary spices including black pepper, cayenne pepper, cinnamon, ginger, Mediterranean oregano, rosemary, and turmeric were extracted with boiling water. Major chemical constituents were characterized by RP-HPLC-DAD method and antioxidant capacity was determined by measuring colorimetrically the extent to scavenge ABTS radical cations. Effects of spice extracts on the viability of 88 anaerobic and facultative isolates from intestinal microbiota were determined by using Brucella agar plates containing serial dilutions of extracts. A total of 14 phenolic compounds, a piperine, cinnamic acid, and cinnamaldehyde were identified and quantitated. Spice extracts exhibited high antioxidant capacity that correlated with the total amount of major chemicals. All spice extracts, with the exception of turmeric, enhanced the growth of Bifidobacterium spp. and Lactobacillus spp. All spices exhibited inhibitory activity against selected Ruminococcus species. Cinnamon, oregano, and rosemary were active against selected Fusobacterium strains and cinnamon, rosemary, and turmeric were active against selected Clostridium spp. Some spices displayed prebiotic-like activity by promoting the growth of beneficial bacteria and suppressing the growth of pathogenic bacteria, suggesting their potential role in the regulation of intestinal microbiota and the enhancement of gastrointestinal health. The identification and quantification of spice-specific phytochemicals provided insight into the potential influence of these chemicals on the gut microbial communities and activities. Future research on the connections between spice-induced changes in gut microbiota and host metabolism and disease preventive effect in animal models and humans is needed.

Pomegranate ellagitannins stimulate the growth of Akkermansia muciniphila in vivo

Results from our previous human pomegranate extract (POM extract) intervention study demonstrated that about seventy percent of participants were able to form urolithin A from ellagitannins in the intestine (urolithin A producers). Urolithin A formation was associated with a high proportion of Akkermansia muciniphila in fecal bacterial samples as determined by 16S rRNA sequencing. Here we investigated whether A. muciniphila counts increased in stool samples collected after the POM extract intervention compared to baseline stool samples using real-time PCR. In addition, we performed in vitro culture studies to determine the effect of POM extract and ellagic acid on the growth of A. muciniphila and to analyze ellagic acid metabolites formed in the culture broth by high-performance liquid chromatography. Supplementation of culture broth with 10 μM of ellagic acid did not change A. muciniphila growth while the addition of 0.18 mg/ml and 0.28 mg/ml of POM extract to the culture broth inhibited the growth of A. muciniphila significantly. Incubation of A. muciniphila with POM extract resulted in formation of ellagic acid and incubation of A. muciniphila with ellagic acid demonstrated hydrolysis of ellagic acid to metabolites different from urolithin A. The in vitro culture studies with A. muciniphila partially explain our in vivo findings that the presence of A. muciniphila was associated with breakdown of ellagic acid for further metabolism by other members of the microbiota. This is the first report of the role of A. muciniphila in ellagitannin hydrolysis. However, we conclude that enzymes from other bacteria must be involved in the formation of urolithin A in the human intestine.

Phytoestrogens Induce Differential Estrogen Receptor Alpha- or Beta-Mediated Responses in Transfected Breast Cancer Cells

Increased intake of phytoestrogens may be associated with a lower risk of cancer in the breast and several other sites, although there is controversy surrounding this activity. One of the mechanisms proposed to explain the activity of phytoestrogens is their ability to bind and activate human estrogen receptor a (ERα) and human estrogen receptor β (ERβ). Nine phytoestrogens were tested for their ability to transactivate ERα or ERβ at a range of doses. Mammary adenocarcinoma (MCF-7) cells were co-transfected with either ERα or ERβ, and an estrogen-response element was linked to a luciferase reporter gene. Dose-dependent responses were compared with the endogenous ligand 17β-estradiol. Purified genistein, daidzein, apigenin, and coumestrol showed differential and robust transactivation of ERα- and ERβ-induced transcription, with an up to 100-fold stronger activation of ERβ. Equol, naringenin, and kaempferol were weaker agonists. When activity was evaluated against a background of 0.5 nM 17β-estradiol, the addition of genistein, daidzein, and resveratrol superstimulated the system, while kaempferol and quercetin were antagonists at the highest doses. This transfection assay provides an excellent model to evaluate the activation of ERα and ERβ by different phytoestrogens in a breast cancer context and can be used as a screening bioassay tool to evaluate the estrogenic activity of extracts of herbs and foods.

Nutrition Intervention in Cancer

Nutrition intervention supports the patient with malnutrition secondary to cancer and its treatment and has been used in the primary and secondary prevention of common forms of cancer. During the emotional stress of dealing with cancer at any stage, patients derive increased quality of life and a sense of control over their lives as the result of receiving supportive advice on diet and lifestyle. Therefore, the use of nutrition intervention in cancer patients is justified in the absence of absolute proof of efficacy as long as it is done safely and with the consent of the cancer patient.