Prunes preserve cortical density and estimated strength of the tibia in a 12-month randomized controlled trial in postmenopausal women: The Prune Study

Non-pharmacological therapies, such as whole-food interventions, are gaining interest as potential approaches to prevent and/or treat low bone mineral density (BMD) in postmenopausal women. Previously, prune consumption preserved two-dimensional BMD at the total hip. Here we demonstrate that prune consumption preserved three-dimensional BMD and estimated strength at the tibia.

PURPOSE

Dietary consumption of prunes has favorable impacts on areal bone mineral density (aBMD); however, more research is necessary to understand the influence on volumetric BMD (vBMD), bone geometry, and estimated bone strength.

METHODS

This investigation was a single center, parallel arm 12-month randomized controlled trial (RCT; NCT02822378) to evaluate the effects of 50 g and 100 g of prunes vs. a Control group on vBMD, bone geometry, and estimated strength of the radius and tibia via peripheral quantitative computed tomography (pQCT) in postmenopausal women. Women (age 62.1 ± 5.0yrs) were randomized into Control (n = 78), 50 g Prune (n = 79), or 100 g Prune (n = 78) groups. General linear mixed effects (LME) modeling was used to assess changes over time and percent change from baseline was compared between groups.

RESULTS

The most notable effects were observed at the 14% diaphyseal tibia in the Pooled (50 g + 100 g) Prune group, in which group × time interactions were observed for cortical vBMD (p = 0.012) and estimated bone strength (SSI; p = 0.024); all of which decreased in the Control vs. no change in the Pooled Prune group from baseline to 12 months/post.

CONCLUSION

Prune consumption for 12 months preserved cortical bone structure and estimated bone strength at the weight-bearing tibia in postmenopausal women.

Effects of Prune (Dried Plum) Supplementation on Cardiometabolic Health in Postmenopausal Women: An Ancillary Analysis of a 12-Month Randomized Controlled Trial, The Prune Study

BACKGROUND

Estrogen withdrawal during menopause is associated with an unfavorable cardiometabolic profile. Prunes (dried plums) represent an emerging functional food and have been previously demonstrated to improve bone health. However, our understanding of the effects of daily prune intake on cardiometabolic risk factors in postmenopausal women is limited.

OBJECTIVES

We conducted an ancillary investigation of a randomized controlled trial (RCT), The Prune Study, to evaluate the effect of 12-mo prune supplementation on cardiometabolic health markers in postmenopausal women.

METHODS

The Prune Study was a single-center, parallel-design, 12-mo RCT in which postmenopausal women were allocated to no-prune control, 50 g/d prune, or 100 g/d prune groups. Blood was collected at baseline, 6 mo, and 12 mo/post to measure markers of glycemic control and blood lipids. Body composition was assessed at baseline, 6 mo, and 12 mo/post using dual-energy X-ray absorptiometry. Linear mixed-effects models were used to evaluate the effect of time, treatment, and their interaction on cardiometabolic health markers, all quantified as exploratory outcomes.

RESULTS

A total of 183 postmenopausal women (mean age, 62.1 ± 4.9 y) completed the entire 12-mo RCT: control (n = 70), 50 g/d prune (n = 67), and 100 g/d prune (n = 46). Prune supplementation at 50 g/d or 100 g/d did not alter markers of glycemic control and blood lipids after 12 mo compared with the control group (all P > 0.05). Furthermore, gynoid percent fat and visceral adipose tissue (VAT) indices did not significantly differ in women consuming 50 g/d or 100 g/d prunes compared with the control group after 12 mo of intervention. However, android total mass increased by 3.19% ± 5.5% from baseline in the control group, whereas the 100 g/d prune group experienced 0.02% ± 5.6% decrease in android total mass from baseline (P < 0.01).

CONCLUSIONS

Prune supplementation at 50 g/d or 100 g/d for 12 mo does not improve glycemic control and may prevent adverse changes in central adiposity in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT02822378.

Effect of Probiotic Supplementation on Intestinal Permeability in Overweight and Obesity: A Systematic Review of Randomized Controlled Trials and Animal Studies

Overweight and obesity are associated with increased intestinal permeability, characterized by loss of gut epithelial integrity, resulting in unregulated passage of lipopolysaccharide (LPS) and other inflammatory triggers into circulation, i.e., metabolic endotoxemia. In obesity, shifts in the gut microbiome negatively impact intestinal permeability. Probiotics are an intervention that can target the gut microbiome by introducing beneficial microbial species, potentially restoring gut barrier integrity. Currently, the role of probiotic supplementation in ameliorating obesity- and overweight-associated increases in gut permeability has not been reviewed. This systematic review aimed to summarize findings from both animal and clinical studies that evaluated the effect of probiotic supplementation on obesity-induced impairment in intestinal permeability (International Prospective Register of Systematic Reviews, CRD42022363538). A literature search was conducted using PubMed (Medline), Web of Science, and CAB Direct from origin until August 2023 using keywords of intestinal permeability, overweight or obesity, and probiotic supplementation. Of 920 records, 26 eligible records were included, comprising 12 animal and 14 clinical studies. Clinical trials ranged from 3 to 26 wk and were mostly parallel-arm (n = 13) or crossover (n = 1) design. In both animal and clinical studies, plasma/serum LPS was the most common measure of intestinal permeability. Eleven of 12 animal studies reported a positive effect of probiotic supplementation in reducing intestinal permeability. However, results from clinical trials were inconsistent, with half reporting reductions in serum LPS and half reporting no differences after probiotic supplementation. Bifidobacterium, Lactobacillus, and Akkermansia emerged as the most common genera in probiotic formulations among the animal and clinical studies that yielded positive results, suggesting that specific bacteria may be more effective at reducing intestinal permeability and improving gut barrier function. However, better standardization of strain use, dosage, duration, and the delivery matrix is needed to fully understand the probiotic impact on intestinal permeability in individuals with overweight and obesity.

The Effects of Bifidobacterium Probiotic Supplementation on Blood Glucose: A Systematic Review and Meta-Analysis of Animal Models and Clinical Evidence

Probiotic supplementation is a potential therapeutic for metabolic diseases, including obesity, metabolic syndrome (MetS), and type 2 diabetes (T2D), but most studies deliver multiple species of bacteria in addition to prebiotics or oral pharmaceuticals. This may contribute to conflicting evidence in existing meta-analyses of probiotics in these populations and warrants a systematic review of the literature to assess the contribution of a single probiotic genus to better understand the contribution of individual probiotics to modulate blood glucose. We conducted a systematic review and meta-analysis of animal studies and human randomized controlled trials (RCTs) to assess the effects of Bifidobacterium (BF) probiotic supplementation on markers of glycemia. In a meta-analysis of 6 RCTs, BF supplementation had no effect on fasting blood glucose {FBG; mean difference [MD] = -1.99 mg/dL [95% confidence interval (CI): -4.84, 0.86], P = 0.13}, and there were no subgroup differences between subjects with elevated FBG concentrations and normoglycemia. However, BF supplementation reduced FBG concentrations in a meta-analysis comprised of studies utilizing animal models of obesity, MetS, or T2D [n = 16; MD = -36.11 mg/dL (CI: -49.04, -23.18), P < 0.0001]. Translational gaps from animal to human trials include paucity of research in female animals, BF supplementation in subjects that were normoglycemic, and lack of methodologic reporting regarding probiotic viability and stability. More research is necessary to assess the effects of BF supplementation in human subjects with elevated FBG concentrations. Overall, there was consistent evidence of the efficacy of BF probiotics to reduce elevated FBG concentrations in animal models but not clinical trials, suggesting that BF alone may have minimal effects on glycemic control, may be more effective when combined with multiple probiotic species, or may be more effective in conditions of hyperglycemia rather than elevated FBG concentrations.

Prune consumption attenuates pro-inflammatory cytokine secretion and alters monocyte activation in postmenopausal women: secondary outcome analysis of a 12-month randomized controlled trial: The Prune Study

BACKGROUND

Pro-inflammatory cytokines are implicated in the pathophysiology of postmenopausal bone loss. Clinical studies demonstrate that prunes prevent bone mineral density loss; however, the mechanism underlying this effect is unknown.

OBJECTIVE

We investigated the effect of prune supplementation on immune, inflammatory, and oxidative stress markers.

METHODS

A secondary analysis was conducted in the Prune Study, a single-center, parallel-arm, 12-month randomized controlled trial of postmenopausal women (55-75 years old; n=235 recruited; n=183 completed) who were assigned to one of three groups: "no-prune" control, 50g/day and 100g/day prune groups. At baseline and after 12 months of intervention, blood samples were collected to measure serum high-sensitivity C-reactive protein (hs-CRP), serum total antioxidant capacity (TAC), plasma 8-isoprostane, pro-inflammatory cytokines [interleukin (IL)-1β, IL-6, IL-8, monocyte chemoattractant protein-1, and tumor necrosis factor (TNF)-α] in plasma and lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) culture supernatants, and the percentage and activation of circulating monocytes, as secondary outcomes.

RESULTS

Prune supplementation did not alter hs-CRP, TAC, 8-isoprostane, and plasma cytokine concentrations. However, percent change from baseline in circulating activated monocytes was lower in the 100g/day prune group compared to the control group (mean±SD, -1.8±4.0% in 100g/day prune vs. 0.1±2.9% in control; p<0.01). Furthermore, in LPS-stimulated PBMC supernatants, the percent change from baseline in TNF-α secretion was lower in the 50g/day prune group compared to the control group (-4.4±43.0% in 50g/day prune vs. 24.3±70.7% in control; p<0.01), and the percent change from baseline in IL-1β, IL-6, and IL-8 secretion was lower in the 100g/day prune group compared to the control group (-8.9±61.6, -4.3±75.3, -14.3±60.8% in 100g/day prune vs. 46.9±107.4, 16.9±70.6, 39.8±90.8% in control for IL-1β, IL-6, and IL-8, respectively; all p<0.05).

CONCLUSION

Dietary supplementation with 50g-100g prunes for 12 months reduced pro-inflammatory cytokine secretion from PBMCs and suppressed the circulating levels of activated monocytes in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT02822378.

Changes in the Type 2 diabetes gut mycobiome associate with metformin treatment across populations

The human gut teems with a diverse ecosystem of microbes, yet non-bacterial portions of that community are overlooked in studies of metabolic diseases firmly linked to gut bacteria. Type 2 diabetes mellitus (T2D) associates with compositional shifts in the gut bacterial microbiome and fungal mycobiome, but whether T2D and/or pharmaceutical treatments underpin the community change is unresolved. To differentiate these effects, we curated a gut mycobiome cohort to-date spanning 1,000 human samples across 5 countries and a murine experimental model. We use Bayesian multinomial logistic normal models to show that metformin and T2D both associate with shifts in the relative abundance of distinct gut fungi. T2D associates with shifts in the Saccharomycetes and Sordariomycetes fungal classes, while the genera Fusarium and Tetrapisipora most consistently associate with metformin treatment. We confirmed the impact of metformin on individual gut fungi by administering metformin to healthy mice. Thus, metformin and T2D account for subtle, but significant and distinct variation in the gut mycobiome across human populations. This work highlights for the first time that oral pharmaceuticals can confound associations of gut fungi with T2D and warrants the need to consider pharmaceutical interventions in investigations of linkages between metabolic diseases and gut microbial inhabitants.

Associations Between Leisure-Time Physical Activity Level and Peripheral Immune Cell Populations in the US General Population, Analysis of the National Health and Nutrition Examination Survey Data, 1999-2018

BACKGROUND

Chronic levels of inflammation are associated with higher risk of many chronic diseases. Physical activity (PA) lowers the risk of cancer, cardiovascular disease (CVD), diabetes and others. One mechanism for PA-induced protection may be through the immune system. We investigated the association between leisure-time PA and peripheral immune cell populations in a large nationally representative sample of the US general population.

METHODS

A total of 17,093 participants [mean (SE) age of 41.6 (0.3) years] of the National Health and Nutrition Examination Survey 1999-2018 were included. Self-reported leisure-time PA was converted to metabolic equivalent of task hours per week (MET-hrs/wk). White blood cell (WBC) count, WBC ratios, and platelet count were derived. Multivariable linear regression analyses were used to estimate associations between leisure-time PA level and peripheral immune cell populations. Multivariable logistic regression analyses were used to estimate associations between leisure-time PA and metrics of WBC count and neutrophil-to-lymphocyte ratio (NLR) which may predict mortality.

RESULTS

A higher leisure-time PA level was associated with a lower WBC count (> 14.0 vs. < 1.2 MET-hrs/wk adjusted mean (95% confidence interval [CI]): 7.12 (6.86, 7.38) vs. 7.38 (7.12, 7.64) 1000 cells/μL, Ptrend < 0.001) and a lower NLR (> 14.0 vs. < 1.2 MET-hrs/wk adjusted mean (95% CI) 2.04 (1.90, 2.18) vs. 2.13 (1.99, 2.28), Ptrend = 0.007). Leisure-time PA level was not associated with lymphocyte-to-monocyte ratio (LMR; Ptrend = 0.25) or platelet-to-lymphocyte ratio (PLR; Ptrend = 0.69). Compared to the lowest leisure-time PA level (< 1.2 MET-hrs/wk), the highest leisure-time PA level (≥ 14.0 MET-hrs/wk) was associated with a lower probability of a high WBC count (> 8.1 × 109 cells/L; odds ratio [OR] = 0.76, 95% CI = 0.66-0.88) and high NLR (> 2.68; OR = 0.84, 95% CI = 0.72-0.99), which may predict CVD and all-cause mortality. The highest leisure-time PA level also linked to a lower probability of a high WBC count (≥ 8.3 × 109 cells/L; OR = 0.76, 95% CI = 0.66-0.88), which may predict cancer mortality.

CONCLUSIONS

We observed an inverse association between leisure-time PA level, WBC count, and NLR, particularly for neutrophil levels. These results suggest that participants at higher levels of leisure-time PA may have lower levels of inflammation, which may be important for future chronic disease outcomes.

Intraoral Gavage of Second-Generation Probiotic Lactobacillus Reuteri Releasing IFN-β (LR-IFN-β) Mitigates Intestinal Irradiation Toxicity and Improves Survival During Whole Abdomen Irradiation (WAI)

PURPOSE/OBJECTIVE(S)

We sought to establish a method by which to overcome the toxicity of WAI to facilitate clinical application in Ovarian Cancer patients.

MATERIALS/METHODS

We irradiated C57BL/6J mice to 19.75 Gy WAI and assessed the primary endpoint of overall survival (OS). In a separate experiment, mice were irradiated to 12 Gy WAI and intestinal barrier integrity was compared between groups: control (0 Gy), irradiation only, 12 Gy + LR, 12 Gy + IFN-β, and 12 Gy + LR-IFN-β. Luminex assay of plasma and intestinal cells were also assayed at day 5 after WAI for radiation-induced inflammatory cytokines, and fecal matter was analyzed for LR-IFN-β clearance and levels of the LR-derived IFN-β gene from day 1 to 5 in control non-irradiated mice. Moreover, fluorescent beads were intraorally administered three hours prior to sacrifice at days 2 or 5 after WAI, and blood was assayed for beads.

RESULTS

Mice receiving LR-IFN-β (109 bacteria in 100 mL of saline) 24-hours following a single fraction of 19.75 Gy WAI showed improved OS compared to control irradiated mice (p = 0.03). LR-IFN-β gavage maintained intestinal barrier integrity (p < 0.05) by stimulating intestinal stem cells regenerations (improved levels of Lgr5+ cells, occludin, and I-CAM; p < 0.05), and reduced levels of intestinal pro-inflammatory cytokines, including IFN-γ (p = 0.0261), IL-3 (p < 0.0020) and IL-17 (p < 0.0070). There was no significant effect of control LR or intraperitoneal injection of IFN-β protein at 24 hours after WAI. Detectable levels of LR-IFN-β bacteria were also cleared from fecal matter by day three via colony assay and rt-PCR, with no detectable growth of LR-IFN-β in blood from gavaged irradiated mice (13.5 Gy WAI).

CONCLUSION

LR-IFN-β is both a feasible and effective radiation mitigator that could potentially improve the management of ovarian cancer patients. Furthermore, the subsequent addition of platinum/taxane-based chemotherapy to the combination of WAI and LR-IFN-β should reduce tumor volume while protecting the intestine and thus improve overall survival in ovarian cancer patients.

Associations Between Inflammatory Mediators and Bone Outcomes in Postmenopausal Women: A Cross-Sectional Analysis of Baseline Data from the Prune Study

Purpose

Hypoestrogenism triggers increased production of inflammatory mediators, which contribute to bone loss during postmenopausal osteoporosis. This study aimed to investigate the association between circulating inflammatory markers and bone outcomes in postmenopausal women.

Materials and methods

We conducted a cross-sectional, secondary analysis of baseline data from participants who completed a 12-month randomized controlled trial, The Prune Study (NCT02822378), which included healthy postmenopausal women (n=183, 55-75 years old) with bone mineral density (BMD) T-score between 0.0 and -3.0 at any site. BMD was measured using dual-energy X-ray absorptiometry, and bone geometry and strength were measured using peripheral quantitative computed tomography. Blood was collected at baseline to measure (1) serum biomarkers of bone turnover, including procollagen type 1 N-terminal propeptide (P1NP) and C-terminal telopeptide and (2) inflammatory markers, including serum high-sensitivity C-reactive protein (hs-CRP) and plasma pro-inflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, and monocyte chemoattractant protein (MCP)-1, using enzyme-linked immunosorbent assay. The associations between bone and inflammatory outcomes at baseline were analyzed using correlation and regression analyses.

Results

Serum hs-CRP negatively correlated with P1NP (r=-0.197, p=0.042). Plasma IL-1β, IL-6, IL-8, and TNF-α negatively correlated with trabecular bone score at the lumbar spine (all p<0.05). In normal-weight women, plasma IL-1β, IL-6, and IL-8 negatively correlated (p<0.05) with trabecular and cortical bone area, content, and density at various sites in the tibia and radius. Serum hs-CRP positively predicted lumbar spine BMD (β=0.078, p=0.028). Plasma IL-6 negatively predicted BMD at the total body (β=-0.131, p=0.027) and lumbar spine (β=-0.151, p=0.036), whereas plasma TNF-α negatively predicted total hip BMD (β=-0.114, p=0.028).

Conclusion

At baseline, inflammatory markers were inversely associated with various estimates of bone density, geometry, and strength in postmenopausal women. These findings suggest that inflammatory markers may be an important mediator for postmenopausal bone loss.

The Role of Prunes in Modulating Inflammatory Pathways to Improve Bone Health in Postmenopausal Women

The prevalence of osteoporosis among women aged 50 y and older is expected to reach 13.6 million by 2030. Alternative nonpharmaceutical agents for osteoporosis, including nutritional interventions, are becoming increasingly popular. Prunes (dried plums; Prunus domestica L.) have been studied as a potential whole-food dietary intervention to mitigate bone loss in preclinical models of osteoporosis and in osteopenic postmenopausal women. Sixteen preclinical studies using in vivo rodent models of osteopenia or osteoporosis have established that dietary supplementation with prunes confers osteoprotective effects both by preventing and reversing bone loss. Increasing evidence from 10 studies suggests that, in addition to antiresorptive effects, prunes exert anti-inflammatory and antioxidant effects. Ten preclinical studies have found that prunes and/or their polyphenol extracts decrease malondialdehyde and NO secretion, increase antioxidant enzyme expression, or suppress NF-κB activation and proinflammatory cytokine production. Two clinical trials have investigated the impact of dried plum consumption (50-100 g/d for 6-12 mo) on bone health in postmenopausal women and demonstrated promising effects on bone mineral density and bone biomarkers. However, less is known about the impact of prune consumption on oxidative stress and inflammatory mediators in humans and their possible role in modulating bone outcomes. In this review, the current state of knowledge on the relation between inflammation and bone health is outlined. Findings from preclinical and clinical studies that have assessed the effect of prunes on oxidative stress, inflammatory mediators, and bone outcomes are summarized, and evidence supporting a potential role of prunes in modulating inflammatory and immune pathways is highlighted. Key future directions to bridge the knowledge gap in the field are proposed.

Metformin modulates the gut microbiome in broiler breeder hens

Broiler breeder hens, the parent stock of commercial broiler chickens, are genetically selected for rapid growth. Due to a longer production period and the focus of genetic selection on superior carcass traits in their progeny, these hens have the propensity to gain excess adipose tissue and exhibit severe ovarian dysfunction, a phenotype that is similar to human polycystic ovary syndrome (PCOS). Metformin is an antihyperglycemic drug approved for type 2 diabetes that is prescribed off-label for PCOS with benefits on metabolic and reproductive health. An additional effect of metformin treatments in humans is modulation of gut microbiome composition, hypothesized to benefit glucose sensitivity and systemic inflammation. The effects of dietary metformin supplementation in broiler breeder hens have not been investigated, thus we hypothesized that dietary metformin supplementation would alter the gut microbiome of broiler breeder hens. Broiler breeder hens were supplemented with metformin at four different levels (0, 25, 50, and 75 mg/kg body weight) from 25 to 65 weeks of age, and a subset of hens (n = 8–10 per treatment group) was randomly selected to undergo longitudinal microbiome profiling with 16S rRNA sequencing. Metformin impacted the microbial community composition in 75 mg/kg metformin compared to controls (adjusted PERMANOVA p = 0.0006) and an additional dose-dependent difference was observed between 25 mg/kg and 75 mg/kg (adjusted PERMANOVA p = 0.001) and between 50 mg/kg and 75 mg/kg (adjusted PERMANOVA p = 0.001) but not between 25 mg/kg and 50 mg/kg (adjusted PERMANOVA p = 0.863). There were few differences in the microbiome attributed to hen age, and metformin supplementation did not alter alpha diversity. Bacteria that were identified as differentially relatively abundant between 75 mg/kg metformin treatment and the control, and between metformin doses, included Ruminococcus and members of the Clostridia family that have been previously identified in human trials of PCOS. These results demonstrate that metformin impacts the microbiome of broiler breeder hens in a dose-dependent manner and several findings were consistent with PCOS in humans and with metformin treatment in type 2 diabetes. Metformin supplementation is a potentially promising option to improve gut health and reproductive efficiency in broiler breeder hens.

Preventive Nutrition: Heart Disease and Cancer

Two of the leading chronic diseases are cardiovascular disease (CVD) and cancer. A cornerstone of prevention for CVD and cancer is a healthy dietary pattern throughout the lifespan. Dietary patterns represent the totality of the diet and reflect habitual consumption of combinations and quantities of foods and nutrients that cumulatively affect health and disease. This article summarizes recent evidence on the relationship of diet quality as measured by adherence to healthy dietary patterns and CVD and cancer risk reduction. Optimal adherence to a healthy dietary pattern decreases CVD and cancer risk; even small changes in diet quality are beneficial.

A longitudinal study of the impact of university student return to campus on the SARS-CoV-2 seroprevalence among the community members

Returning university students represent large-scale, transient demographic shifts and a potential source of transmission to adjacent communities during the COVID-19 pandemic. In this prospective longitudinal cohort study, we tested for IgG antibodies against SARS-CoV-2 in a non-random cohort of residents living in Centre County prior to the Fall 2020 term at the Pennsylvania State University and following the conclusion of the Fall 2020 term. We also report the seroprevalence in a non-random cohort of students collected at the end of the Fall 2020 term. Of 1313 community participants, 42 (3.2%) were positive for SARS-CoV-2 IgG antibodies at their first visit between 07 August and 02 October 2020. Of 684 student participants who returned to campus for fall instruction, 208 (30.4%) were positive for SARS-CoV-2 antibodies between 26 October and 21 December. 96 (7.3%) community participants returned a positive IgG antibody result by 19 February. Only contact with known SARS-CoV-2-positive individuals and attendance at small gatherings (20-50 individuals) were significant predictors of detecting IgG antibodies among returning students (aOR, 95% CI 3.1, 2.07-4.64; 1.52, 1.03-2.24; respectively). Despite high seroprevalence observed within the student population, seroprevalence in a longitudinal cohort of community residents was low and stable from before student arrival for the Fall 2020 term to after student departure. The study implies that heterogeneity in SARS-CoV-2 transmission can occur in geographically coincident populations.

Rational and study design of Randomized Controlled Trial of Dietary Supplementation with prune (dried plums) on bone density, geometry, and estimated bone strength in postmenopausal women: The Prune study

The use of non-pharmacological alternatives to pharmacological interventions, e.g., nutritional therapy, to improve or maintain bone mineral density (BMD) in postmenopausal women has gained traction over the past decade, but limited data exist regarding its efficacy. This paper describes the design of the Prune Study, a randomized controlled trial (RCT) that explored the effectiveness of a 12-month intervention of daily prune consumption on bone density, bone structure and strength estimates, bone turnover, various biomarkers of immune function, inflammation, and cardiovascular health, as well as phenolic and gut microbiota analyses. Postmenopausal women between the ages of 55–75 years were randomized into either control group (no prune consumption; n = 78), 50g prune (50g prune/day; n = 79), or 100g prune (100g prune/day; n = 78). All participants received 1200 mg calcium +800 IU vitamin D₃ daily as standard of care. The Prune Study is the largest and most comprehensive investigation of a dose response of prune consumption on bone health, biomarkers of immune function, inflammation, and cardiovascular health, as well as detailed phenolic and gut microbiota analyses in postmenopausal women. 235 women were randomized and 183 women completed the entire study. The findings of this study will help expand our current understanding of clinical implications and mechanisms underlying the resultant health effects of prune as a functional food therapy.

12-MONTH PRUNE CONSUMPTION ALTERS THE GUT MICROBIOME IN POSTMENOPAUSAL WOMEN

Prunes have health benefits, particularly in postmenopausal women. It is likely that the gut microbiome mediates some of these effects, but its exact role remains to be elucidated. This study...

Four weeks of spice consumption lowers plasma proinflammatory cytokines and alters the function of monocytes in adults at risk of cardiometabolic disease: secondary outcome analysis in a 3-period, randomized, crossover, controlled feeding trial

BACKGROUND

Numerous studies demonstrate acute anti-inflammatory properties of individual spices, but none have examined the effect of longer-term consumption of a spice blend incorporated in a meal.

OBJECTIVES

We investigated the effect of longer-term spice consumption on inflammatory cytokines and monocyte subsets [classical (CM), intermediate (IM), nonclassical (NCM)] in adults at risk of cardiometabolic disease.

METHODS

A 3-period, randomized, crossover, controlled feeding trial was conducted. Participants (n = 71 recruited; n = 63 completed) randomly consumed diets differing in terms of the quantity of spices: 0.547 g (low-dose spice diet; LSD), 3.285 g (medium-dose spice diet; MSD), or 6.571 g (high-dose spice diet; HSD) · d-1 · 2100 kcal-1, for 4 wk with a ≥2-wk washout between diets. At baseline and after each diet period, proinflammatory cytokines (IL-1β, IL-6, IL-8, monocyte chemoattractant protein-1, and TNF-α) in plasma and LPS-stimulated peripheral blood mononuclear cell culture supernatants, and the phenotype and function of monocyte subsets, were measured in fasted participants. Postprandial proinflammatory cytokines also were quantified at baseline by consumption of a low-spice-dose test meal, and after each diet period by consumption of a test meal containing a spice dose corresponding to daily spice consumption during the preceding 4-wk diet period.

RESULTS

Fasting plasma IL-6 was reduced (mean ± SEM: -118.26 ± 50.63 fg/mL; P < 0.05) after MSD compared with baseline. Postprandial plasma IL-1β, IL-8, and TNF-α were lower (mean ± SEM : -9.47 ± 2.70 fg/mL, -0.20 ± 0.05 pg/mL, and -33.28 ± 12.35 fg/mL, respectively) after MSD compared with LSD (main diet effect; P < 0.05). CM adherence was reduced (mean ± SEM: -0.86 ± 0.34; P = 0.034) after HSD compared with LSD. IM migration was reduced after MSD and HSD compared with LSD (mean ± SEM: -0.39 ± 0.09 and -0.56 ± 0.14, respectively; P < 0.05).

CONCLUSIONS

Four weeks of MSD consumption reduced fasting plasma IL-6 and postprandial plasma IL-1β, IL-8, and TNF-α as well as altering monocyte function.This trial was registered at clinicaltrials.gov as NCT03064932.

Herbs and spices at a relatively high culinary dosage improves 24-hour ambulatory blood pressure in adults at risk of cardiometabolic diseases: a randomized, crossover, controlled-feeding study

BACKGROUND

Intake of a single meal containing herbs and spices attenuates postprandial lipemia, hyperglycemia, and oxidative stress, and improves endothelial function. There has been limited investigation of the effect of longer-term intake of mixed herbs and spices on risk factors for cardiometabolic diseases.

OBJECTIVES

The objective was to assess the effect of an average American diet containing herbs and spices at 0.5 (low-spice diet; LSD), 3.3 (moderate-spice diet; MSD), and 6.6 (high-spice diet; HSD) g · d-1 · 2100 kcal-1 on lipids and lipoproteins as well as other risk factors for cardiometabolic diseases in at-risk adults.

METHODS

A 3-period, randomized, crossover, controlled-feeding study with 71 participants was conducted at the Pennsylvania State University. Each diet was consumed for 4 wk with a minimum 2-wk washout period. Outcomes were assessed at baseline and the end of each diet period.

RESULTS

No between-diet effects were observed for LDL cholesterol, the primary outcome. Between-diet differences were observed for mean 24-h systolic (P = 0.02) and diastolic (P = 0.005) ambulatory blood pressure. The HSD lowered mean 24-h systolic blood pressure compared with the MSD (-1.9 mm Hg; 95% CI: -3.6, -0.2 mm Hg; P = 0.02); the difference between the HSD and LSD was not statistically significant (-1.6 mm Hg; 95% CI: -3.3, 0.04 mm Hg; P = 0.058). The HSD lowered mean 24-h diastolic blood pressure compared with the LSD (-1.5 mm Hg; 95% CI: -2.5, -0.4 mm Hg; P = 0.003). No differences were detected between the LSD and MSD. No between-diet effects were observed for clinic-measured blood pressure, markers of glycemia, or vascular function.

CONCLUSIONS

In the context of a suboptimal US-style diet, addition of a relatively high culinary dosage of mixed herbs and spices (6.6 g · d-1 · 2100 kcal-1) tended to improve 24-h blood pressure after 4 wk, compared with lower dosages (0.5 and 3.3 g · d-1 · 2100 kcal-1), in adults at elevated risk of cardiometabolic diseases.This trial was registered at clinicaltrials.gov as NCT03064932.

In utero and childhood exposure to the Great Chinese Famine and risk of cancer in adulthood: the Kailuan Study

BACKGROUND

The risk of cancer in adulthood can be influenced by exposure to environmental factors (e.g., food shortage and stress) in early life.

OBJECTIVES

This study compared the risk of cancer morbidity and mortality between Chinese adults who were or were not exposed to the Great Chinese Famine (1959-1961) in utero or during early childhood.

METHODS

The Kailuan Study participants (n = 101,095) were classified into 5 famine exposure groups by birth year collected at study baseline (2006-2007): after 1961 (unexposed), 1959-1961 (in utero exposed), 1956-1958 (infancy and early childhood exposed, aged 0.1-2.9 y), 1953-1955 (childhood exposed, aged 3.0-5.9 y), and before 1953 (exposed, aged 6+ y). They were further classified by the severity of famine exposure. Cancer and cancer mortality cases from 2006 to 2016 were confirmed by reviewing medical records. Cox proportional hazard models were computed, adjusting for sex, socioeconomic status, and other time-varying cancer-related covariates.

RESULTS

During a median follow-up of 10.0 y, we identified 3560 incident cancer cases and 1749 cancer deaths. Famine exposure at all ages was positively associated with the risk of cancer morbidity and mortality (P < 0.001 for all, compared with unexposed). Severe exposure to famine in early childhood, but not other ages, had a higher risk of composite cancer events [adjusted HR = 2.04 (95% CI: 1.47, 2.84) for 0.1-2.9 y; and 1.61 (95% CI: 1.15, 2.25) for 3.0-5.9 y], relative to the less severely exposed groups of the same age range. When cancer morbidity and mortality were studied separately, similar patterns were observed.

CONCLUSIONS

In utero and early childhood exposures to famine, especially severe famine, were associated with a higher risk of cancer morbidity and mortality in adulthood. Awareness should be raised regarding the long-term effect of early life nutritional status.Trial registration number: ChiCTR-TNRC-11001489 (http://www.chictr.org.cn/showprojen.aspx?proj=8050).

SARS-CoV-2 Seroprevalence in a University Community: A Longitudinal Study of the Impact of Student Return to Campus on Infection Risk Among Community Members

BACKGROUND

Returning university students represent large-scale, transient demographic shifts and a potential source of transmission to adjacent communities during the COVID-19 pandemic.

METHODS

In this prospective longitudinal cohort study, we tested for IgG antibodies against SARS-CoV-2 in a non-random cohort of residents living in Centre County prior to the Fall 2020 term at the Pennsylvania State University and following the conclusion of the Fall 2020 term. We also report the seroprevalence in a non-random cohort of students collected at the end of the Fall 2020 term.

RESULTS

Of 1313 community participants, 42 (3.2%) were positive for SARS-CoV-2 IgG antibodies at their first visit between 07 August and 02 October 2020. Of 684 student participants who returned to campus for fall instruction, 208 (30.4%) were positive for SARS-CoV-2 antibodies between 26 October and 21 December. 96 (7.3%) community participants returned a positive IgG antibody result by 19 February. Only contact with known SARS-CoV-2-positive individuals and attendance at small gatherings (20-50 individuals) were significant predictors of detecting IgG antibodies among returning students (aOR, 95% CI: 3.1, 2.07-4.64; 1.52, 1.03-2.24; respectively).

CONCLUSIONS

Despite high seroprevalence observed within the student population, seroprevalence in a longitudinal cohort of community residents was low and stable from before student arrival for the Fall 2020 term to after student departure. The study implies that heterogeneity in SARS-CoV-2 transmission can occur in geographically coincident populations.

Effects of Diet and Exercise-Induced Weight Loss on Biomarkers of Inflammation in Breast Cancer Survivors: A Systematic Review and Meta-analysis

BACKGROUND

Adiponectin, leptin, and pro- and anti-inflammatory cytokines are implicated in breast cancer risk and recurrence. Weight loss, via the dynamic interplay of energy balance through exercise and/or caloric restriction, decreases risk of breast cancer recurrence.

METHODS

We investigated the effects of lifestyle modifications (exercise only, or combined caloric restriction and exercise) on adipokines, IL2, IL6, IL8, IL10, C-reactive protein (CRP), and TNFα biomarkers in breast cancer survivors. Searches were completed in June and July of 2019 to identify randomized controlled trials that met inclusion criteria. Weighted mean difference was calculated using random- or fixed-effects models based on the heterogeneity of the studies.

RESULTS

2501 records were identified, with 30 ultimately meeting inclusion criteria of the systematic review; 21 studies provided data suitable for meta-analysis. We observed leptin levels were significantly reduced in the exercise-only group compared with sedentary control [WMD -5.66; 95% confidence interval (CI), -11.0 to -0.33; P = 0.04].

CONCLUSIONS

Leptin may be a primary mediator of exercise-induced improvements in breast cancer recurrence.

IMPACT

This is the first review and meta-analysis to examine combined exercise and caloric restriction programs in breast cancer survivors. Future studies should further examine combined programs and their efficacy for altering leptin.

The Association Between Monocyte Subsets and Cardiometabolic Disorders/Cardiovascular Disease: A Systematic Review and Meta-Analysis

Background: Monocyte subsets in humans, i.e., classical (CM), intermediate (IM), and non-classical monocytes (NCM), are thought to differentially contribute to the pathogenesis of atherosclerosis, the leading cause of cardiovascular disease (CVD). However, the association between monocyte subsets and cardiometabolic disorders and CVD is not well-understood. Thus, the aim of the current systematic review and meta-analysis was to evaluate recent findings from clinical studies that examined the association between the distribution of monocyte subsets in subjects with cardiometabolic disorders and CVD compared to healthy controls.

Methods: Articles were systematically searched in CINAHL, PubMed and Cochrane Library. Articles were independently screened and selected by two reviewers. Studies that reported the percentage of each monocyte subset were included in the systematic review and meta-analysis. For the meta-analysis, a random-effects model was used to generate pooled standardized mean differences (SMD) between subjects with cardiometabolic disorders and healthy controls.

Results: A total of 1,693 articles were screened and 27 studies were selected for qualitative analyses. Among them, six studies were included in the meta-analysis. In total, sample size ranged from 22 to 135 and mean or median age from 22 to 70 years old. We found studies that reported higher percentage and number of IM and/or NCM in subjects with cardiometabolic disorders (9 out of 13 studies) and in subjects with CVD (11 out of 15 studies) compared to healthy controls. In the meta-analysis, the percentage of CM was lower [SMD = −1.21; 95% CI (−1.92, −0.50); P = 0.0009; I² = 91%] and the percentage of IM [SMD = 0.56; 95% CI (0.23, 0.88); P = 0.0008; I² = 65%] and NCM [SMD = 1.39; 95% CI (0.59, 2.19); P = 0.0007; I² = 93%] were higher in subjects with cardiometabolic disorders compared to healthy controls.

Conclusions: Individuals with cardiometabolic disorders and CVD may have a higher percentage of IM and NCM than healthy controls. Future studies are needed to evaluate the cause and biological significance of this potential altered distribution of monocyte subsets.

Physical Activity and Breast Cancer Prevention: Possible Role of Immune Mediators

There is strong evidence that physical activity (PA) reduces risk, recurrence, and mortality from breast cancer. Emerging data suggest that PA induces changes in inflammatory and immune mediators that may contribute to beneficial effects on breast cancer outcomes. Thus, the goal of this review was to evaluate the evidence linking the protective benefit of PA to modulation of immune responses in breast cancer. A literature search was conducted to identify studies that evaluated the impact of PA on tumor and immune outcomes in breast cancer patients and in mammary tumor models. Nineteen studies investigated the effect of PA interventions on cancer immune outcomes using preclinical breast cancer models. Tumor growth was reduced in 11 studies, unchanged in three studies, and increased in one study. Spontaneous metastasis was reduced in two studies and survival was improved in four studies. Frequently assessed immune outcomes include splenic cell number and function, circulating inflammatory cytokines, and intratumoral immune cells and inflammatory markers. Circulating inflammatory cytokine responses were heterogeneous in preclinical models. Within the tumor microenvironment (TME), several studies documented a change in the infiltration of immune cells with an increase in effector cells and a reduction in immune suppressive cells. Twenty-three studies investigated the effect of PA interventions on immune outcomes in breast cancer patients. Thirteen studies used aerobic PA interventions and 10 studies used a combination of aerobic and resistance exercise interventions. Cycling and treadmill activities were the most commonly used PA modalities. Circulating immune cells and inflammatory cytokines were the most frequently assessed immune outcomes in the clinical studies. Among the 19 studies that evaluated a PA intervention during the post treatment period, 10 reported a reduction in the levels of at least one inflammatory cytokine. No inflammatory cytokines were quantified in the three studies that evaluated a PA intervention during treatment with chemotherapy. Immune outcomes within the tumor were assessed in only one study performing a PA intervention prior to surgery. Results from preclinical and clinical studies suggest that PA exerts heterogeneous effects on inflammatory cytokines, but may alter the gene expression profile and immune infiltrates in the tumor which may result in a reduction in immunosuppressive factors. However, additional studies are needed to better understand the effect of PA on immune outcomes in the TME.

Impact of physical activity and energy restriction on immune regulation of cancer

Cancer is a major public health issue worldwide. Lifestyle factors, such as body weight and physical activity (PA), significantly impact cancer risk and progression. There is strong evidence that PA reduces and obesity increases risk and mortality from numerous cancer types. Energy restriction (ER) in non-obese hosts significantly reduces tumor incidence in a variety of preclinical models, and reduces body weight and cardiometabolic risk factors in humans. Emerging data suggest that PA- and ER-induced changes in inflammatory and immune mediators may contribute to the cancer prevention effects of these interventions. A systematic literature search was conducted to identify studies that evaluated the impact of PA and ER on tumor and immune outcomes in humans and animal models. A total of 97 eligible studies were identified (68 studies reporting PA interventions and 30 studies reporting ER interventions). Thirty-one studies investigated the effect of PA on cancer immune outcomes using preclinical cancer models of breast (n=17, 55%), gastrointestinal (n=6, 19%), melanoma (n=4, 13%), and several other cancer types (n=4, 13%). Despite the heterogeneity in study designs, the majority of studies (n=23, 74%) reported positive effects of PA on tumor outcomes. Thirty-seven clinical studies investigated the effect of PA on cancer immune outcomes. None reported tumor outcomes, thus only immune outcomes were evaluated in these studies. PA studies were conducted in patients with breast (n=22, 59%), gastrointestinal (n=5, 14%), prostate (n=2, 5%), esophageal (n=1, 3%), lung (n=1, 3%) cancer, leukemia (n=1, 3%), or mixed cancer types (n=5, 14%). Twenty-two studies investigated the effect of ER interventions on cancer immune outcomes using preclinical cancer models including breast (n=5, 23%), gastrointestinal (n=5, 23%), lung (n=2, 9%), liver (n=2, 9%), pancreatic (n=2, 9%), and several other cancer types (n=6, 27%). Positive effects of ER on tumor outcomes were reported in 21 of 22 studies. Six clinical studies investigated the effect of ER (in combination with PA) on tumor immune outcomes in cancer patients with overweight or obesity. Five were conducted in breast cancer patients, and one recruited patients of a mix of cancer types. A wide range of immunological parameters including immune cell phenotype and function, cytokines, and other immune and inflammatory markers were assessed in multiple tissue compartments (blood, spleen, lymph nodes and tumor) in the included studies. Results from preclinical and clinical studies suggest that both PA and ER exert heterogeneous effects on circulating factors and systemic immune responses. PA + ER alters the gene expression profile and immune infiltrates in the tumor which may result in a reduction in immune suppressive factors. However, additional studies are needed to better understand the effect of PA and/or ER on immunomodulation, particularly in the tumor microenvironment (TME).

Spices in a High-Saturated-Fat, High-Carbohydrate Meal Reduce Postprandial Proinflammatory Cytokine Secretion in Men with Overweight or Obesity: A 3-Period, Crossover, Randomized Controlled Trial

BACKGROUND

Postprandial inflammation that occurs concurrently with hyperglycemia and hyperlipidemia after ingestion of a high-saturated-fat, high-carbohydrate meal (HFCM) is a risk factor for cardiovascular disease (CVD). Numerous preclinical and clinical studies demonstrate anti-inflammatory effects of individual spices. However, the effect of consumption of a spice blend on inflammatory mediators has not been examined in a randomized controlled trial.

OBJECTIVES

The objective of this study was to investigate the postprandial effect of a blend of spices in a HFCM on inflammatory cytokine responses.

METHODS

Nonsmoking men (40-65 y old) with overweight/obesity (25 ≤ BMI ≤ 35 kg/m2), elevated waist circumference (≥ 94 cm), and ≥ 1 CVD risk factor were recruited for a 3-period crossover study ( n = 12). In random order, participants consumed the following: a HFCM (∼1000 kcal, 33% kcal from saturated fat and 36% kcal from carbohydrate), a HFCM containing 2 g spice blend, or an HFCM containing 6 g spice blend. The spice blend consisted of basil, bay leaf, black pepper, cinnamon, coriander, cumin, ginger, oregano, parsley, red pepper, rosemary, thyme, and turmeric. Blood was collected before, and hourly for 4 h after the HFCM. Peripheral blood mononuclear cells (PBMCs) were isolated, and the percentage of CD14 +/Human Leukocyte Antigen-DR isotype + (HLA-DR +) monocytes and proinflammatory cytokine concentrations in plasma and LPS-stimulated PBMCs were quantified as secondary outcomes.

RESULTS

There was a significant spice-by-time interaction on IL-1β (P < 0.001), IL-8 (P = 0.020), and TNF-α (P = 0.009) secretion from LPS-stimulated PBMCs. IL-1β secretion from LPS-stimulated PBMCs was significantly reduced (1314%) at 240 min after HFCM consumption containing 6 g, but not 2 g, of spice blend compared with 0 g spice blend.

CONCLUSIONS

A HFCM containing 6 g spice blend attenuated HFCM-induced postprandial IL-1β secretion in men with overweight/obesity.This trial was registered at clinicaltrials.gov as NCT03064958.

The effect of culinary doses of spices in a high-saturated fat, high-carbohydrate meal on postprandial lipemia and endothelial function: a randomized, controlled, crossover pilot trial

Previously it has been shown that incorporation of >11 g of spices into a mixed meal blunts postprandial lipemia, which may reduce acute endothelial impairment. The effect of lower doses of spices remains unclear. The aim was to examine the postprandial effect of a meal high in saturated fat and carbohydrate inclusive of spices (2 g or 6 g) or exclusive of spices (0 g) on flow mediated dilation (FMD), lipids and lipoproteins, glucose, and insulin in men at-risk for cardiovascular disease. A 3-period randomized, controlled, crossover, pilot study was conducted. In random order, subjects consumed a high-saturated fat, high-carbohydrate meal (1076 kcal, 39 g saturated fat, 98 g carbohydrate) with 0 g, 2 g and 6 g of mixed spices. After meal consumption, blood was drawn hourly for 4 hours and FMD was measured at 2 and 4 hours. Serum lipids and lipoproteins, and insulin were measured in the fasting state and at each post-meal time point; plasma glucose was also assessed at each time point. Subjects were 13 men aged 52 ± 9 years that were overweight or obese (29.9 ± 3.1 kg m^-2), and had an enlarged waist circumference (102.2 ± 8.9 cm). Time (p < 0.05) and treatment (p < 0.05) effects existed for FMD and triglycerides; no time by treatment interactions were detected. Post hoc testing showed that the meal with 6 g of spices lessened the postprandial reduction in FMD compared to the meal with no spices (-0.87 ± 0.32%; p = 0.031); no other pairwise differences were observed. Triglyceride levels were lower following the meal with 2 g of spices vs. the no spice meal (-18 ± 6 mg dL^-1; p = 0.015); no difference was observed between the meal with 6 g of spice and the no spice meal (-13 ± 6 mg dL^-1; p = 0.12). Glucose and insulin were unaffected by the presence of spices in the meal. In conclusion, this study provides preliminary evidence suggesting that lower doses of spices (2 and 6 g) than previously tested may attenuate postprandial lipemia and impairments in endothelial function caused by a high-saturated fat, high-carbohydrate meal.

Increased Adiposity Enhances the Accumulation of MDSCs in the Tumor Microenvironment and Adipose Tissue of Pancreatic Tumor-Bearing Mice and in Immune Organs of Tumor-Free Hosts

Obesity is associated with increased risk and reduced survival for many types of cancer. Increasing adiposity may affect the balance between immunosuppressive and antitumor mechanisms critical for dictating cancer progression or remission. The goal of the current study was to determine if increased adiposity altered tumor growth, survival, and myeloid-derived suppressor cell (MDSC) accumulation in a subcutaneous murine model of pancreatic cancer. C57BL/6 mice were placed on a 30% kcal calorie-restricted diet, 10% kcal from fat diet fed ad libitum, or 60% kcal from fat diet fed ad libitum for 16 weeks to generate lean, overweight, and obese mice, respectively; followed by subcutaneous injection with 1 × 10⁶ Panc.02 cells. We observed a significant linear relationship between increased adiposity and increased tumor growth and mortality; increased accumulation of Gr-1⁺CD11b⁺ MDSCs; and reduced CD8 T cell:MDSC ratio in multiple tissues, including tumor. Increased adiposity also increased the accumulation of MDSCs in the spleen and lymph node of tumor-free mice. These data suggest adiposity induces MDSC accumulation, which may contribute to an immunosuppressive environment promoting tumor growth. Overall, our findings provide a rationale to prevent or reverse increased body weight as a strategy to reduce the accumulation of immunosuppressive cell types.

Physical Activity Plus Energy Restriction Prevents 4T1.2 Mammary Tumor Progression, MDSC Accumulation, and an Immunosuppressive Tumor Microenvironment

Physical activity and the prevention of weight gain decrease breast cancer incidence and improve survival. Unraveling the biological mechanisms underlying these cancer prevention effects is difficult because activity and dietary restriction are often linked. The goal of this study was to determine whether physical activity (PA), preventing weight gain via energy restriction (ER), or the combination was most effective in delaying tumor growth, reducing metastatic progression, and improving survival in the 4T1.2 mammary tumor model. Furthermore, we determined whether any of these interventions prevented the expansion of protumor immunosuppressive cells and altered the tumor microenvironment (TME). Female BALB/c mice (n = 7-20/group) were randomized to sedentary (SED) or PA wheel cages and fed ad libitum (AL) or 90% of control food intake (ER). After 8 weeks on the interventions, mice were inoculated with 5 × 10⁴ 4T1.2^luc cells into the 4th mammary fat pad and continued on their respective intervention. PA+ER significantly delayed primary tumor growth (final tumor volume, 0.193 ± 0.042 vs. 0.369 ± 0.049 cm³, P < 0.001), reduced metastatic burden in the lungs (0.72 ± 0.36 vs. 16.27 ± 6.98, P = 0.054) and increased survival (median survival, 68 vs 40 days, P = 0.043) compared with SED+AL mice. PA+ER also reduced the expression level of metastatic and immunosuppressive genes and resulted in favorable changes in immune cell infiltrates in the tumor. These data suggest that both PA and ER are needed to reduce tumor growth, delay metastatic progression, and improve survival, and that this protection is associated with changes in immune-mediated mechanisms.

Abstract 586: CD4+and CD8+T cells influence 4T1.2luc mammary tumor growth and survival

The 4T1.2 syngeneic murine breast cancer model is an aggressive model of stage IV triple-negative breast cancer. Despite its significant strength, the 4T1.2 model is poorly immunogenic with few defined tumor antigens. The firefly luciferase gene, luc2, has been transfected into various tumor cell lines as a reporter for bioluminescence imaging. However, studies have shown that the luciferase (Luc) may serve as a tumor antigen and induce CD8+ cytotoxic T cell responses. The goal of the current study was to determine if luciferase expression in 4T1.2 tumor cells would enhance the immunogenicity of the tumor, and explore the role of immune effector cells in the parental 4T1.2 and luciferase-transfected 4T1.2luc tumor model. In vitro proliferation of the 4T1.2 and 4T1.2luc cells was assessed using the MTS cell proliferation assay. For in vivo experiments, female BALB/c mice were randomized into 2 groups and orthotopically injected with 5x104 4T1.2 or 4T1.2luc cells, respectively. Tumor growth was assessed until day 35 post tumor implantation. Each group was further randomized into 5 subgroups and received i.p. injections of PBS, rat IgG2b mAb, anti-CD4 mAb, anti-CD8 mAb, or anti-asialo GM1. Mice were sacrificed between day 28-35 post tumor implantation, and lung metastases were analyzed for each group. To further evaluate the immunogenicity of luciferase in the 4T1.2luc model, a separate cohort of mice were orthotopically injected with 5x104 4T1.2luc cells and sacrificed at day 35 post tumor implantation. Splenocytes were harvested and cultured in the presence of 1 or 10 µg/ml peptides representing MHC I-restricted Luc epitopes for 5 days, and cytotoxicity of the effector cells was assessed by the chromium-release assay. In vitro proliferation rates were not significantly different between 4T1.2 and 4T1.2luc tumor cells. However, 4T1.2luc tumor-bearing mice showed a significant reduction in primary tumor growth compared to 4T1.2 tumor-bearing mice. 4T1.2 primary tumor growth was not altered by the depletion of any immune cell type, while 4T1.2luc primary tumor growth was significantly increased by the depletion of CD8+ T cells, and reduced by the depletion of NK cells. Depletion of CD4+ T cells, CD8+ T cells or NK cells in 4T1.2luc tumor-bearing mice resulted in a significant reduction in median survival. Splenocytes from 4T1.2luc tumor bearing mice demonstrated Luc-specific cytotoxicity upon ex vivo restimulation with Luc peptides, and a stronger response was observed when cells were restimulated with 1 µg/ml compared to 10 µg/ml Luc peptides. These findings suggest that luciferase may serve as a tumor antigen in the 4T1.2luc tumor model, and host immune components (CD4+ and CD8+ T cells) may play a role in controlling 4T1.2luc primary tumor growth and survival. The stronger immunogenicity of 4T1.2luc conferred by luciferase will enable future immunotherapeutic research that ultimately may benefit breast cancer patients.

Citation Format: Yitong Xu, Shizhao Duan, William J. Turbitt, Andrea M. Mastro, Connie J. Rogers. CD4+and CD8+T cells influence 4T1.2luc mammary tumor growth and survival [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 586.

Aligning the Paradoxical Role of Vitamin D in Gastrointestinal Immunity

Inflammatory bowel disease (IBD) is a chronic disorder characterized by inflammation of the gastrointestinal tract and an immune-mediated attack against the commensal microbiota. Vitamin D is an essential vitamin that not only promotes calcium and phosphate absorption but also regulates immune function. The active form of vitamin D [1,25(OH)₂D] has been shown to suppress symptoms of IBD by inhibiting T cell responses. Host protection from gastrointestinal infection depends on T cells. Paradoxically, vitamin D deficiency increases susceptibility to IBD and gastrointestinal infection. Here we review the roles of vitamin D in immune cells using a kinetic model of the vitamin D-mediated effects on infection to explain the sometimes paradoxical effects of vitamin D on gastrointestinal immunity.

Cancer- and Chemotherapy-Induced Musculoskeletal Degradation

Mobility in advanced cancer patients is a major health care concern and is often lost in advanced metastatic cancers. Erosion of mobility is a major component in determining quality of life but also starts a process of loss of muscle and bone mass that further devastates patients. In addition, treatment options become limited in these advanced cancer patients. Loss of bone and muscle occurs concomitantly. Advanced cancers that are metastatic to bone often lead to bone loss (osteolytic lesions) but may also lead to abnormal deposition of new bone (osteoblastic lesions). However, in both cases there is a disruption to normal bone remodeling and radiologic evidence of bone loss. Many antitumor therapies can also lead to loss of bone in cancer survivors. Bone loss releases cytokines (TGFβ) stored in the mineralized matrix that can act on skeletal muscle and lead to weakness. Likewise, loss of skeletal muscle mass leads to reduced bone mass and quality via mechanical and endocrine signals. Collectively these interactions are termed bone-muscle cross-talk, which has garnered much attention recently as a prime target for musculoskeletal health. Pharmacological approaches as well as nutrition and exercise can improve muscle and bone but have fallen short in the context of advanced cancers and cachexia. This review highlights our current knowledge of these interventions and discusses the difficulties in treating severe musculoskeletal deficits with the emphasis on improving not only bone mass and muscle size but also functional outcomes. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.

Abstract 2240: Diet and exercise-induced weight maintenance, alone and in combination with a whole tumor cell vaccine, delays mammary tumor growth and reduces tumor-infiltrating MDSCs expressing PD-L1 and IDO

Obesity and physical inactivity increase breast cancer risk, while the prevention of weight gain by diet and exercise can be protective. Numerous biological mechanisms are proposed to explain the beneficial effects of weight maintenance, including changes in metabolic, inflammatory and immune mediators. We have previously shown that diet and exercise-induced weight maintenance (WM), in combination with a whole 4T1.2luc tumor cell vaccine (VAX), significantly reduced mammary tumor growth and metastases in the 4T1.2luc murine mammary tumor model. This reduction in growth and metastases occurred concomitantly with an elevation in tumor antigen-induced splenic IFN-γ production and a reduction in the accumulation of splenic myeloid-derived suppressor cells (MDSCs) at day 35 post-tumor implantation. The goal of the current study was to determine if WM+VAX alters the tumor microenvironment at an early stage of tumor growth (day 24 post-tumor implantation) which may contribute to reduced tumor growth and enhanced immune outcomes at day 35 post-tumor implantation. Female BALB/c mice were randomized into sedentary, weight gain (WG) or exercising (access to voluntary running wheel), weight maintenance (WM) groups (n=22-27/group). After 8 weeks on the intervention, all mice were orthotopically injected with 5x104 4T1.2luc cells into the fourth mammary fat pad and continued on their intervention. Once injected, both WG and WM mice were further randomized into vaccination (VAX) or vehicle control (VEH) groups (n=10-15/group) and administered 1x106 irradiated 4T1.2luc cells (VAX) or HBSS (VEH) at day 7, 14 and 21 post-tumor implantation. Mice were sacrificed at day 24 post-tumor implantation and tumor-infiltrating immune cells were isolated for analyses. Both WM+VEH and WM+VAX groups showed a significant reduction in primary tumor growth and splenomegaly compared to both WG groups (p&lt;0.001). Flow cytometric analysis demonstrated that the combination of WM+VAX significantly reduced total tumor-infiltrating MDSCs and MDSCs expressing PD-L1 and indoleamine 2,3-dioxygenase (IDO) compared to WG+VEH (p&lt;0.05). This finding was consistent with a 1.5-4.5 fold decrease in the gene expression level of Pdcd1, Ido1 and Ifng in the total tumor infiltrates. These results suggest that the combination of weight maintenance and the whole tumor cell vaccine may be altering both the number and immunosuppressive capacity of tumor-infiltrating MDSCs. Thus, preventing weight gain through diet and exercise may be an important recommendation in combination with immune-based therapies to enhance efficacy and improve clinical outcomes. This work is supported by R21 CA209144; T32GM108563. W.J.T is currently funded by the NIH T32DK062710 grant; NORC, UAB, Birmngham, AL.

Citation Format: Yitong Xu, William J. Turbitt, Andrea M. Mastro, Connie J. Rogers. Diet and exercise-induced weight maintenance, alone and in combination with a whole tumor cell vaccine, delays mammary tumor growth and reduces tumor-infiltrating MDSCs expressing PD-L1 and IDO [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2240.

Linking the Gut Microbiota to Bone Health in Anorexia Nervosa

PURPOSE OF REVIEW

The purpose of this review is to examine the anorexia nervosa-microbiota-bone relationship, offering a compilation of the relevant human and animal studies that may contribute to a more comprehensive understanding of potential mechanisms involved.

RECENT FINDINGS

Recent studies have implicated fermentation by-products of the gut microbiota in bone metabolism. Compromised bone health often accompanies anorexia nervosa due to energy deficiency and hypoestrogenism. The gut microbiome has been implicated as a link between these conditions and impaired bone growth phenotypes. Current research supports decrements in Firmicutes and short-chain fatty acids with increases in Methanobrevibacter smithii and Proteobacteria in anorexia nervosa. A potential mechanism for microbiome-regulated bone growth is through modulation of insulin-like growth factor-1. Future research should aim to examine short-chain fatty acids, probiotics, and prebiotics as alternative therapies to treat low bone density in anorexia nervosa.

Abstract 243: Diet and exercise-induced weight maintenance, alone and in combination with a whole tumor cell vaccine, delays mammary tumor growth and reduces MDSC accumulation

Obesity and physical inactivity increase breast cancer risk, while the prevention of weight gain by diet and exercise can be protective. Numerous biological mechanism(s) have been proposed to explain the beneficial effects of weight maintenance; however few studies have examined the immune response to energy balance. We have previously shown that diet and exercise-induced weight maintenance (WM) achieved via a 10% restriction in calories and access to voluntary running wheels in combination with a whole tumor cell vaccine (VAX) significantly reduced mammary tumor growth and metastases in the 4T1 mammary tumor model. This WM-induced reduction in tumor growth occurred concurrently with an elevation in tumor specific IFN-γ production and a reduction in the number of myeloid-derived suppressor cells (MDSCs). However, because tumor size is positively correlated with immune suppression, the goal of the current study was to investigate if mice in the WM+VAX intervention had enhanced anti-tumor immune responses and/or fewer MDSCs controlling for tumor size. Female BALB/c mice were randomized into weight gain (WG) and WM groups (n=8/group) and had access to voluntary running wheels or standard cages, respectively. WG mice were fed ad libitum while WM mice were energy-restricted by 10% to maintain a stable body weight. After 8 weeks on the intervention, all mice were orthotopically injected with 5x104 4T1.2 cells into the fourth mammary fat pad and continued on their intervention. Once injected, both WG and WM mice were further randomized into vaccination (VAX) and vehicle control (VEH) groups (n=4/gr) and administered 1x106 irradiated 4T1.2 cells (VAX) or HBSS (VEH) at day 7 post-tumor implantation. Primary tumor growth was quantified, and mice were sacrificed when tumor volume reached 0.1-0.2 cm3. WM mice weighed significantly less than WG mice over the course of the study (p&lt;0.001). Mice in both WM+VEH and WM+VAX groups took a significantly longer number of days post tumor implantation to reach a tumor size of 0.1-0.2 cm3 (26.3 ± 3.3 d, p=0.003; 23.8 ± 0.5 d, p=0.039, respectively) compared to the WG+VEH group (18.3 ± 2.5 d). Despite the fact that mice were sacrificed when the tumor volumes were standardized at 0.1-0.2 cm3, the combination of WM+VAX resulted in a significant reduction of splenic MDSC accumulation (p=0.049) and enhanced CD4+ T cell proliferation ex vivo. These results suggest that diet and exercise-induced WM was highly effective in delaying primary mammary tumor growth. The combination of WM and an allogenic whole tumor cell vaccine reduced pro-tumorigenic MDSC accumulation and enhanced effector T cell function. Furthermore, these data suggest that diet and exercise may be changing the tumor microenvironment at an early stage of tumor growth favoring tumor clearance. This work is supported by R21 CA209144; T32AI074551.

Citation Format: Yitong Xu, William J. Turbitt, Andrea M. Mastro, Connie J. Rogers. Diet and exercise-induced weight maintenance, alone and in combination with a whole tumor cell vaccine, delays mammary tumor growth and reduces MDSC accumulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 243. doi:10.1158/1538-7445.AM2017-243

Effects of Bifidobacterium animalis subsp. lactis BB-12® on the lipid/lipoprotein profile and short chain fatty acids in healthy young adults: a randomized controlled trial

Background

Some probiotics have hypocholesterolemic effects in animal studies, which are mediated, in part, by increases in fecal short chain fatty acids (SCFAs). Clinical trials of probiotics on lipids/lipoproteins are inconsistent.

Objective

We examined the effects of Bifidobacterium animalis subsp. lactis BB-12^® (BB-12^®) (3.16 × 10⁹ CFUs/day) on lipids and lipoproteins and fecal excretion of SCFAs in healthy adults.

Methods

In a randomized, partially blinded, 4-period, crossover study, 30 adults (11 men, 19 women) aged 18–40 years were randomly assigned to: 1) yogurt smoothie with no BB-12^® (YS), 2) yogurt smoothie with BB-12^® added pre-fermentation (PRE), 3) yogurt smoothie with BB-12^® added post-fermentation (POST), 4) BB-12^® containing capsule (CAP). We measured serum lipids/lipoproteins, glucose, insulin, C-reactive protein (CRP), and fecal SCFAs at baseline and after each treatment period.

Results

Total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and triglycerides (TGs) did not differ after the PRE, POST, and CAP periods versus the YS or between treatments. Compared to baseline, fecal acetate was significantly increased after the YS (Δ = 211.89 ± 75.87 μg/g, P = 0.007) and PRE (Δ = 204.98 ± 75.70 μg/g, P = 0.009) periods. The percent increase in fecal acetate was significantly greater after the YS versus the POST period (52.2 ± 13.2% vs. 24.5 ± 13.2%, P = 0.023). Fecal total SCFAs, propionate and butyrate did not differ between treatment periods. Fecal total SCFAs were negatively associated with TC (r = -0.22, P = 0.01), LDL-C (r = -0.24, P = 0.004), age (r = -0.33, P < 0.001), and waist circumference (r = -0.25, P = 0.003).

Conclusions

BB-12^® supplementation did not improve lipids, lipoproteins and total and individual fecal SCFAs. Fecal SCFAs were negatively associated with TC, LDL-C, age, and waist circumference.

Trial registration

This trial was registered at clinicaltrials.gov as NCT01399996.

Bioactive growth hormone in older men and women: It's relationship to immune markers and healthspan

OBJECTIVE

The consequences of age-related decline in the somatotropic axis of humans are complex and remain largely unresolved. We tested the hypothesis that hGH measurements of plasma by bioassay vs immunoassay from samples obtained from free-living, elderly individuals would reveal a dichotomy in GH activities that are correlated with the functional status of the donors, i.e. their healthspan.

DESIGN

Forty-one men and women of advanced age (men: N=16, age, 80.5±6.5years; height, 173.1±6.9cm; body mass, 81.8±13.0kg) and (women: N=25, age, 80.7±7.2years; height, 157.7±6.0cm; body mass, 68.8±17kg), were recruited for a cross-sectional study. Participants filled out PROMIS (Patient-Reported Outcomes Measurement Information System, U. S. Department of Health and Human Services) scales, undertook physical performance tests and had fasted blood samples obtained at rest for measurement of hormonal and immunology biomarkers.

RESULTS

When measured by the well-established rat tibial line GH bioassay, one half of the plasma samples (n=20) contained bioassayable GH (bGH), but the other half (n=21) failed to mount increases in tibial plate width above saline injected controls. This difference did not correlate with the age, sex or physical functionality of the plasma donor. It also did not correlate with hGH concentrations measured by immunoassay. In those cases in which bGH was detected, various hierarchical regression models predicted that GHRH, c-peptide, VEGF, NPY, IL-4 and T-regulatory lymphocytes were associated with the difference and predicted bGH.

CONCLUSION

Results from this study suggest that the actions of bGH at the cellular level may be modified by other factors and that this may explain the lack of correlations observed in this study.

Lipid Emulsion Added to a Liquid High-Carbohydrate Diet and Voluntary Running Exercise Reduce Lipogenesis and Ameliorate Early-Stage Hepatic Steatosis in Mice

Background: The use of parenteral nutrition formulas is often associated with the development of hepatic steatosis. We have shown previously that the addition of a lipid emulsion (LE) rich in n-6 (ω-6) fatty acids (FAs) ameliorated triglyceride (TG) accumulation in the livers of nonobese mice fed a high-carbohydrate diet (HCD) for 5 wk. However, it remains unclear how rapidly this condition develops and whether it can be prevented by LE with or without a running wheel for voluntary exercise (Exe).Objective: We investigated in an 8-d study whether mice develop steatosis and whether the administration of LE with or without Exe reduces the concentration of total FAs and prevents an increase in the expression of genes in the liver associated with lipogenesis.Methods: Male C57BL/6 mice aged 5 wk were randomized into 5 groups: standard feed pellet (SFP); a liquid HCD (77% of total energy from carbohydrates and 0.5% from fat); HCD + Exe; HCD + 13.5% LE (67% carbohydrates and 13.5% fat); or HCD + 13.5% LE + Exe. Hepatic TG concentration, lipogenic genes, and total FAs were measured on day 8.Results: Oil Red O staining and TG quantification showed hepatic TG accumulation on day 8; the addition of 13.5% LE either with or without Exe suppressed the TG accumulation compared with HCD (P < 0.005). With the use of quantitative reverse transcriptase-polymerase chain reaction analysis, the expression concentrations of lipogenic genes [ATP-citrate lyase, acetyl coenzyme A carboxylase 1, FA synthase (Fasn), and stearoyl coenzyme A desaturase 1 (Scd1)] in the HCD + 13.5% LE group were 26-60% of HCD (P < 0.01) and 11-38% of HCD in the HCD + 13.5% LE + Exe group (P < 0.001), with interactions for Fasn and Scd1 (P < 0.05). With the use of gas chromatography-mass spectrometry analysis, the HCD + 13.5% LE group had lower monounsaturated fatty acids (38.7% of HCD) but higher polyunsaturated fatty acids (164% of HCD) (P < 0.001).Conclusions: In short-term studies designed to resemble the early dynamic stage of the development of hepatic steatosis, the addition of 13.5% LE to a liquid HCD reduced hepatic lipogenesis. Exe exerted an independent protective effect and interacted with LE to further reduce the expression of Scd1.

Dietary Iron and Colorectal Cancer Risk: A Review of Human Population Studies

Iron is an essential micronutrient that is involved in many redox processes and serves as an integral component in various physiological functions. However, excess iron can cause tissue damage through its pro-oxidative effects, potentiating the development of many diseases such as cancer through the generation of reactive oxidative species. The two major forms of iron in the diet are heme and nonheme iron, both of which are found in several different foods. In addition to natural food sources, intake of nonheme iron may also come from fortified foods or in supplement form. This review summarizes the results of human population studies that have examined the role of dietary iron (heme and nonheme), heme iron alone, and iron from supplements in colorectal carcinogenesis.

Consumption of Bifidobacterium animalis subsp. lactis BB-12 in yogurt reduced expression of TLR-2 on peripheral blood-derived monocytes and pro-inflammatory cytokine secretion in young adults

PURPOSE

Probiotic bacteria modulate immune parameters and inflammatory outcomes. Emerging evidence demonstrates that the matrix used to deliver probiotics may influence the efficacy of probiotic interventions in vivo. The aims of the current study were to evaluate (1) the effect of one species, Bifidobacterium animalis subsp. lactis BB-12 at a dose of log10 ± 0.5 CFUs/day on immune responses in a randomized, partially blinded, 4-period crossover, free-living study, and (2) whether the immune response to BB-12 differed depending on the delivery matrix.

METHODS

Healthy adults (n = 30) aged 18-40 years were recruited and received four treatments in a random order: (A) yogurt smoothie alone; smoothie with BB-12 added (B) before or (C) after yogurt fermentation, or (D) BB-12 given in capsule form. At baseline and after each 4-week treatment, peripheral blood mononuclear cells (PBMCs) were isolated, and functional and phenotypic marker expression was assessed.

RESULTS

BB-12 interacted with peripheral myeloid cells via Toll-like receptor 2 (TLR-2). The percentage of CD14⁺HLA-DR⁺ cells in peripheral blood was increased in male participants by all yogurt-containing treatments compared to baseline (p = 0.0356). Participants who consumed yogurt smoothie with BB-12 added post-fermentation had significantly lower expression of TLR-2 on CD14⁺HLA-DR⁺ cells (p = 0.0186) and reduction in TNF-α secretion from BB-12- (p = 0.0490) or LPS-stimulated (p = 0.0387) PBMCs compared to baseline.

CONCLUSIONS

These findings not only demonstrate a potential anti-inflammatory effect of BB-12 in healthy adults, but also indicate that the delivery matrix influences the immunomodulatory properties of BB-12.

Fish Oil Enhances T Cell Function and Tumor Infiltration and Is Correlated With a Cancer Prevention Effect in HER-2/neu But Not PyMT Transgenic Mice

Few studies have explored the effects of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on immune modulation in murine models of mammary carcinogenesis. HER-2/neu and PyMT mice were randomized to 2 dietary interventions: AIN-93G-based diet with 1) 11% of diet (per gram weight) as corn oil (CO) or 2) 10% of diet as menhaden fish oil plus 1% of diet as corn oil (FO). FO significantly reduced the incidence and multiplicity of tumors (P < 0.001) in HER-2/neu, but not PyMT mice. FO-fed mice had significantly larger splenocyte counts than CO-fed mice in both the HER-2/neu and PyMT models; and in both models this was comprised of an increase in most cell types, including Gr-1(+)/CD11b(+) cells. T cells from FO-fed HER-2/neu mice produced significantly more interleukin-2 (P = 0.004) and interferon-γ (P = 0.012) in response to in vitro stimulation with anti-CD3 (0.5 µg/ml). Lastly, FO-fed HER-2/neu mice had significantly more tumor immune infiltrates than CO-fed mice, including NK1.1(+), F4/80(+), and Gr-1(+)/CD11b(+) cells (P ≤ 0.05). Greater Th1 cytokine production and significantly more tumor immune infiltrates in FO-fed Her2/neu mice may account for the cancer prevention effect of fish oil in this model.

Decaffeinated Green Tea and Voluntary Exercise Induce Gene Changes Related to Beige Adipocyte Formation in High Fat-Fed Obese Mice

We have previously reported that decaffeinated green tea extract (GTE) in combination with voluntary exercise (Ex) reduces metabolic syndrome in high fat-fed C57BL/6J mice. Here, we examined for the first time the effect of treatment with 77 mg/g GTE, Ex, or both (GTE + Ex) on genes related to the conversion of white adipose tissue (WAT) to brown fat-like adipose tissue (BLAT) in this model. GTE+Ex induced genes related to lipolysis (hormone sensitive lipase [3.0-fold] and patatin-like phospholipase domain-containing protein 2 [2-fold]), mitochondrial β-oxidation (NADH dehydrogenase 5 [2.3-fold], cytochrome B [2.0-fold], and cytochrome C oxidase III [1.9-fold increase]), and adipose tissue browning (peroxisome proliferator-activated receptor-γ coactivator-1α [1.8-fold], bone morphogenetic protein 4 [2.6-fold], and phosphatase and tensin homolog [2.6-fold]) in visceral WAT compared to HF-fed mice. These results suggest that GTE+Ex function in part by inducing the conversion of WAT to BLAT and provides novel mechanistic insight into this combination.

In vitro Production of IL-6 and IFN-γ is Influenced by Dietary Variables and Predicts Upper Respiratory Tract Infection Incidence and Severity Respectively in Young Adults

Assessment of immune responses in healthy adults following dietary or lifestyle interventions is challenging due to significant inter-individual variability. Thus, gaining a better understanding of host factors that contribute to the heterogeneity in immunity is necessary. To address this question, healthy adults [n = 36, 18-40 years old, body mass index (BMI) 20-35 kg/m(2)] were recruited. Dietary intake was obtained via 3-day dietary recall records, physical activity level was evaluated using the International Physical Activity Questionnaire, and peripheral blood mononuclear cells were isolated from peripheral blood. Expression of activation markers on unstimulated immune subsets was assessed by flow cytometry. T-cell proliferation and cytokine secretion was assessed following in vitro stimulation with anti-CD3 or lipopolysaccharide. Furthermore, the incidence and severity of cold or flu symptoms were obtained from self-reported upper respiratory tract infection (URTI) questionnaires. The relationship between activation marker expression on T cells and T-cell effector functions; and in vitro cytokine secretion and URTI was determined by linear or logistic regression. CD69 and CD25 expression on unstimulated T cells was significantly associated with T-cell proliferation and interleukin-2 secretion. Incidence and severity of cold or flu symptoms was significantly associated with in vitro interleukin-6 and interferon-gamma secretion, respectively. Furthermore, host factors (e.g., age, BMI, physical activity, and diet) contributed significantly to the relationship between activation marker expression and T-cell effector function, and cytokine secretion and cold and flu status. In conclusion, these results suggest that lifestyle and dietary factors are important variables that contribute to immune responses and should be included in human clinical trials that assess immune endpoints.

Dietary methionine restriction inhibits prostatic intraepithelial neoplasia in TRAMP mice

BACKGROUND

Prostate cancer (PCa) is a major aging-related disease for which little progress has been made in developing preventive strategies. Over the past several years, methionine restriction (MR), the feeding of a diet low in methionine (Met), has been identified as an intervention which significantly extends lifespan and reduces the onset of chronic diseases, including cancer, in laboratory animals. We, therefore, hypothesized that MR may be an effective strategy for inhibiting PCa.

METHODS

Control (0.86% Met) or MR (0.12% Met) diets were fed to 5-week old TRansgenic Adenocarcinoma of the Mouse Prostate (TRAMP) mice, a well-characterized model for PCa. The mice were sacrificed at 16 weeks of age and prostate and other tissues were harvested for histological and biochemical analyses.

RESULTS

As previously reported, MR was associated with a decrease in body weight which was not associated with lowered food intake. MR led to significant reductions in the development of Prostatic Intraepithelial Neoplasia (PIN) lesions, specifically in the anterior and dorsal lobes of the prostate where the incidence of high-grade PIN was reduced by ∼50% (P < 0.02). The reduction in PIN severity was associated with 46-64% reductions in cell proliferation rates (P < 0.02) and plasma IGF-1 levels (P < 0.0001), which might, in part, explain the effects on carcinogenesis. Additionally, no adverse consequences of MR on immune function were observed in the TRAMP mice.

CONCLUSIONS

Overall, these findings indicate that MR is associated with a reduction in prostate cancer development in the TRAMP model and supports the continued development of MR as a potential PCa prevention strategy.

Vitamin D regulates the gut microbiome and protects mice from dextran sodium sulfate-induced colitis

The active form of vitamin D [1,25-dihydroxycholecalciferol, 1,25(OH)2D3] and the vitamin D receptor (VDR) regulate susceptibility to experimental colitis. The effect of the bacterial microflora on the susceptibility of C57BL/6 mice to dextran sodium sulfate-induced colitis was determined. Mice that cannot produce 1,25(OH)2D3 [Cyp27b1 (Cyp) knockout (KO)], VDR KO as well as their wild-type littermates were used. Cyp KO and VDR KO mice had more bacteria from the Bacteroidetes and Proteobacteria phyla and fewer bacteria from the Firmicutes and Deferribacteres phyla in the feces compared with wild-type. In particular, there were more beneficial bacteria, including the Lactobacillaceae and Lachnospiraceae families, in feces from Cyp KO and VDR KO mice than in feces from wild-type. Helicobacteraceae family member numbers were elevated in Cyp KO compared with wild-type mice. Depletion of the gut bacterial flora using antibiotics protected mice from colitis. 1,25(OH)2D3 treatment (1.25 μg/100 g diet) of Cyp KO mice decreased colitis severity and reduced the numbers of Helicobacteraceae in the feces compared with the numbers in the feces of untreated Cyp KO mice. The mechanisms by which the dysbiosis occurs in VDR KO and Cyp KO mice included lower expression of E-cadherin on gut epithelial and immune cells and fewer tolerogenic dendritic cells that resulted in more gut inflammation in VDR and Cyp KO mice compared with wild-type mice. Increased host inflammation has been shown to provide pathogens with substrates to out-compete more beneficial bacterial species. Our data demonstrate that vitamin D regulates the gut microbiome and that 1,25(OH)2D3 or VDR deficiency results in dysbiosis, leading to greater susceptibility to injury in the gut.