Dietary Protein Intake Associations with Insulin Resistance, BMI, Body Composition and Other Metabolic Markers in Subjects with Prediabetes and Type 2 Diabetes Mellitus (P08-020-19)

Objectives

The incidence of prediabetes and type 2 diabetes mellitus (T2DM) continues to increase and many individuals are not aware of having early stages of the disease until symptoms develop. Much focus has been on carbohydrate consumption for this population, with no established recommendations for protein intake and source. Therefore, the objective of this study was to examine the relationship between protein intake (amount and source) on glycemic control, and indices of cardiovascular health in individuals with prediabetes and T2DM.

Methods

Sixty-two overweight and obese men and women with prediabetes or T2DM, between the ages of 45–75 years participated in this study. Participants were stratified based on their protein intake: below (<0.8 g/kg body weight (bw); n = 17), meeting (0.8–1.0 g/kg bw; n = 22), and above (≥1.0 g/kg bw; n = 23) recommended levels. Measurements included blood biomarkers (lipid panel and glycemic control), anthropometric parameters, food records, and body composition, which were assessed for each group using one-way ANOVA and Pearson correlation coefficient for overall associations. Significance was accepted at (P ≤ 0.05).

Results

Body mass index (BMI), hip circumference (HC) and waist circumference (WC) were significantly higher in participants who consumed below recommended levels compared to above (35.1 ± 1.3 vs. 28.3 ± 0.9 kg/m2; 118.7 ± 3.2 vs. 105.2 ± 1.8 cm; 109.1 ± 2. vs. 96.8 ± 2.5 cm, respectively). Fat-to-lean mass (FM/LM) ratio was significantly lower in participants who consumed above recommended when compared to below and recommended levels (0.63 ± 0.03; 0.81 ± 0.04; 0.78 ± 0.07). Insulin resistance tended to be lower (3.53 ± 0.55 vs 5.19 ± 0.94; P = 0.09) in the above recommended group compared to below. Higher animal-to-plant protein ratios were significantly associated with higher insulin secretion (r = 0.259). Higher animal protein was associated with significantly lower triglyceride concentrations (r = 0.263).

Conclusions

These findings suggest that consumption of ≥1.0 g/kg bw protein was associated with lowered insulin resistance, in addition to lower BMI, HC, WC, and FM, without adverse effects on lipid profiles in this population. Additionally, increased animal protein may be associated with better outcomes for this population.

Funding Sources

There are no funding sources to disclose for this study.

Comparison of Cardiometabolic Biomarkers in Two Groups of US Adults Using Multiple Dietary Supplements: A Cross-Sectional Study (P18-116-19)

Objectives

The aim of the present study is to compare cardiometabolic biomarker levels (MARKERS) from a cohort using multiple (2+) dietary supplements (MDS) manufactured by Shaklee Corporation for 3–5 yr (SHAKLEE) to those from the age-matched MDS users from NHANES 2007–10 (NHANES).

Methods

Each subject from SHAKLEE [n = 58; mean age: 48 yr (22–79 yr)], using MDS manufactured by Shaklee Corp for 3–5 yr, voluntarily signed the IRB approved informed consent form before the study participation. Body mass index (BMI), systolic and diastolic blood pressures (SBP and DSP) were measured, and approximately 30 mL of 12-h fasting blood sample was collected. Pregnant women and people with a history of cancer were excluded. MARKERS from SHAKLEE were compared to those from NHANES [n = 1952; mean age: 51 yr (22–79 yr)]. MARKERS included total cholesterol (TC), HDL-c, TC/HDL-c ratio, LDL-c, triglycerides (TG), high sensitivity C-Reactive Protein (CRP), glucose, hemoglobin A1c (HbA1c), and Insulin levels in the blood as well as BMI, SBP, and DBP. Statistical analyses were performed using independent samples t-tests, and P < 0.05 was considered significantly different between groups.

Results

SHAKLEE had significantly lower TC (189 vs. 201 mg/dL), TC/HDL-c ratio (3.1 vs. 4.0), LDL-c (103 vs. 118 mg/dL), TG (81 vs. 131 mg/dL), glucose (93 vs. 107 mg/dL), HbA1c (5.1 vs. 5.7%), insulin (8.3 vs. 13.4 mIU/L), BMI (26.7 vs. 29.0), and SBP (110 vs. 122 mmHg), and higher HDL-c (69 vs. 55 mg/dL) but had higher DBP (76 vs. 71 mmHg) than NHANES. There was no significant difference in CRP although CRP was slightly lower in SHAKLEE than NHANES (2.9 vs. 3.8 mg/L).

Conclusions

The present study showed that 3–5 yr MDS users from the Shaklee cohort had healthier pattern in cardiometabolic biomarkers than the age-matched MDS users from NHANES 2007–2010.

Funding Sources

Shaklee Corporation, 4747 Willow Road, Pleasanton, CA 94,588, USA.

The Short-Term Effect of Dried Plums on Inflammation and Indices of Bone Health in Osteopenic Men (P01-027-19)

Objectives

Osteoporosis has significant public health importance for both women and men, where 54% of the U.S. population age 50 and older have low bone mineral density (BMD). Chronic inflammation alters bone remodeling, which is one contributor to bone loss; therefore, foods rich in antioxidants, such as dried plums (DP, Prunus domestica L.), are of great interest for preventing chronic inflammation. Previously, dietary intervention with DP has been shown to prevent orichidectomy-induced decreases in BMD, microstructure, and biomechanics in male rats; however, this has yet to be studied in a clinical setting in adult males.

Methods

One-hundred and sixty osteopenic men are being recruited from the greater Tallahassee, Florida area to examine the effects of DP on BMD, bone biomarkers, and inflammation after one year of regular consumption. The present analysis is of a subset of this population, documenting the effects of two doses of DP on biomarkers of inflammation and bone metabolism in men after three months of consumption. Twenty-seven men between the ages of 55 and 80 with moderate bone loss (T-score between −0.1 and −2.5 SD below the mean) were included. The men were randomized into one of three groups: 100 g DP, 50 g DP, or control group, with all three groups given a multivitamin containing 450 mg calcium and 800 IU vitamin D (Shaklee Corporation). Serum samples from the baseline and three-month time points were analyzed for C-reactive protein (CRP) and bone-specific alkaline phosphatase (BAP). DXA scans of the lumbar vertebrae alongside TBS iNnsight® software were used to generate trabecular bone score (TBS).

Results

Three months of DP consumption was associated with numerical increases in BAP in both the 100 g (6.5%, P = 0.14) and 50 g (6.3%, P = 0.3) DP groups, numerical decreases in CRP in both the 100 g (−8.8%, P = 0.75) and 50 g (−8.5%, P = 0.71) DP groups, and minimal change in TBS in both the 100 g (0.37%, P = 0.71) and 50 g (−0.55%, P = 0.44) DP groups.

Conclusions

Regular consumption of either 100 g or 50 g DP for three months may contribute to increases in bone formation and decreases in inflammation, however not to an extent that affects bone quality. Three months of consumption may not be long enough to manifest changes in bone; therefore, further analysis of data after six months and one year of DP consumption in a larger number of men is warranted.

Funding Sources

USDA-NIFA, Shaklee Corporation, California Dried Plum Board.

The Effects of Multi-Day vs. Single Pre-exercise Nitrate Supplement Dosing on Simulated Cycling Time Trial Performance and Skeletal Muscle Oxygenation

Jo, E, Fischer, M, Auslander, AT, Beigarten, A, Daggy, B, Hansen, K, Kessler, L, Osmond, A, Wang, H, and Wes, R. The effects of multiday vs. single pre-exercise nitrate supplement dosing on simulated cycling time trial performance and skeletal muscle oxygenation. J Strength Cond Res 33(1): 217-224, 2019-A transient augmentation in the metabolic efficiency of skeletal muscle is the purported basis for dietary nitrate supplementation amongst competitive and recreational athletes alike. Previous studies support the ergogenic effects of nitrate supplementation, as findings indicated improved microvascular blood flow, exercise economy, and performance with relatively short-term supplementation. As with most ergogenic aids, the optimum duration of supplementation before performance or competition, i.e., loading phase, is a critical determinant for efficacy. Therefore, the purpose of this study was to investigate the effects of long-term vs. single dosing nitrate supplementation on skeletal muscle oxygenation and cycling performance. In a randomized, placebo controlled, double blind, parallel design study, healthy, recreationally active men (n = 15) and women (n = 14) subjects (age = 18-29 years) completed an 8 km (5 mi) simulated cycling time trial before and after a 14-day supplementation period with either a nitrate supplement (Multi-Day Dosing Group) (n = 14) or placebo (Single Pre-Exercise Dosing Group; SD) (n = 15). Both groups consumed a single dose of the nitrate supplement 2 hours before the post-treatment time trial. In addition, skeletal muscle oxygenation was measured via near-infrared spectroscopy during each time trial. Multiday nitrate supplementation significantly decreased time to completion (p = 0.01) and increased average power (p = 0.04) and speed (p = 0.02) from pre-to post-treatment, while a single dosing produced no significant changes to these measures. There were no significant differences over time and across treatments for any other measures including muscle oxygenation variables. Overall, long-term nitrate supplementation appears to have an advantage over a single pre-exercise dosing on cycling performance and metabolic efficiency as indicated by an increase in power output with no change in oxygenation.

Effects of diet and/or low-intensity resistance exercise training on arterial stiffness, adiposity, and lean mass in obese postmenopausal women

BACKGROUND

Obesity and aging are associated with increased arterial stiffness as indicated by an increased pulse-wave velocity (PWV). We evaluated the independent and combined effects on PWV and body composition of a hypocaloric diet and low-intensity resistance exercise training (LIRET) with slow movement.

METHODS

Forty-one postmenopausal women (mean age, 54±6 years; body mass index (BMI), 33.8±0.5kg/m(2)) were randomly assigned to LIRET (n = 14), diet (n = 13), or diet + LIRET (n = 14) for 12 weeks. The women's PWV, mean arterial pressure (MAP), body composition by dual-en ergy x-ray absorptiometry (DXA), and plasma adipokine and insulin levels were measured before and after the interventions.

RESULTS

Body weight (P = 0.0001), trunk-fat mass (FM, P = 0.0001), and the serum concentration of leptin (P = 0.02 and P = 0.004) decreased similarly with diet and diet + LIRET, but not with LIRET alone. Leg lean mass (LM) decreased (P = 0.02) with diet, but did not change with diet + LIRET or with LIRET alone. Leg muscle strength increased similarly with LIRET (P = 0.001) and diet + LIRET (P = 0.0001), but did not change with diet alone. Brachial-ankle PWV (baPWV) decreased with diet (P = 0.04) and diet + LIRET (P = 0.01), whereas femoral-ankle PWV (legPWV) decreased only with diet (P = 0.01). Mean arterial pressure (MAP) decreased after LIRET (P = 0.03), diet (P = 0.04), and diet + LIRET (P = 0.004). Carotid-femoral PWV, serum adiponectin concentration, and insulin were not significantly affected by the interventions examined in the study. The reductions in baPWV and legPWV were correlated with one another (r = 0.73, P = 0.0001), and the reductions in legPWV and trunk FM were also correlated with one another (r = 0.36, P = 0.03).

CONCLUSIONS

A hypocaloric diet decreases baPWV mainly by reducing legPWV, and this reduction is related to the loss of truncal fat. Although LIRET alone does not affect PWV or body composition, LIRET combined with diet improves baPWV and muscle strength while preventing loss of lean body mass in obese postmenopausal women.

Dietary fish oil decreases VLDL production rates

The purpose of the study was to evaluate whether the hypocholesterolemic effect of fish oil in roosters (10% fish oil vs. 10% corn oil in the diet) is due to a decrease in very-low-density lipoprotein (VLDL) secretion rate. Previous studies have shown that in vivo inhibition of lipoprotein lipase with a specific antiserum quantitatively blocks VLDL catabolism. Secretion of VLDL cholesterol and triacylglycerol in fasting roosters was measured during a 4 h inhibition of lipoprotein lipase. Secretion rates of VLDL cholesterol and triacylglycerol were 39% lower (P less than 0.03) and 49% lower (P less than 0.025), respectively, with the fish oil diet. VLDL composition at the end of the inhibition was not remarkably different between treatments. Smaller portomicrons were produced by fish oil feeding (1737 +/- 120 vs. 2090 +/- 64 A, P less than 0.01), but there were no differences seen in Km or Vmax when portomicrons were incubated with purified avian lipoprotein lipase. Plasma cholesterol and triacylglycerol levels were not affected by the oil supplements. In a second study, the diets were supplemented with 0.5% cholesterol in addition to the oils. Fasting serum cholesterol was 52% lower (P less than 0.05) in the fish oil-fed birds, most of the difference being in the VLDL fraction (11.5 +/- 9 vs. 99.7 +/- 66 mg/dl). Low-density lipoprotein cholesterol was also significantly lower. VLDL cholesterol and triacylglycerol secretion rates were lower by 39 (P less than 0.025) and 38% (P less than 0.06), respectively, in the fish oil group. VLDL from fish oil-fed birds collected after a 4 h inhibition had a lower cholesterol content than that from the corn oil-fed birds (15.9 +/- 2.8 vs. 21.2 +/- 1.9 wt%, P less than 0.025). In the fish oil-fed animals the decrease in VLDL cholesterol secretion accounted for 61% of the observed decrease in VLDL cholesterol. The balance of the decrease in plasma VLDL cholesterol was due to a significant increase in VLDL cholesterol fractional removal rate in the fish oil-fed animals from 0.45 +/- 1.0 to 2.63 +/- 1.7 h-1 (P less than 0.01).

Triacylglycerol lipase, monoacylglycerol lipase and phospholipase activities of highly purified rat hepatic lipase

Highly purified rat hepatic lipase (NaCl-resistant, alkaline pH optimum) was studied to evaluate whether the enzyme has triacylglycerol lipase, monoacylglycerol lipase and phospholipase activities. Enzyme exhibiting a single band by SDS-polyacrylamide gel electrophoresis and having a specific activity eight times greater than that in any previous report was utilized. The ratios of the different lipolytic activities to each other remained constant throughout a multistep hepatic lipase purification. The lipolytic activities coeluted by gel filtration on Ultrogel AcA 34. Column isoelectric focusing of the highly purified enzyme revealed comigration of the lipolytic activities. Thermal inactivation produced similar decay curves for the different activities. Immune titration curves for the different activities with specific antibody against hepatic lipase were essentially identical. These findings indicate that hepatic lipase is a single enzyme molecule which has triacyglycerol lipase, monoacylglycerol lipase and phospholipase activities with artificial substrates. To study these lipolytic activities further, purified hepatic lipase was subjected to limited digestion by specific proteases. The triacylglycerol lipase activity was more sensitive to proteolytic destruction than either of the other two activities.