Western Human Nutrition Research Center

Previous studies showed total absorbed zinc (TAZ) was comparable in diets containing a higher zinc rice variety or conventional rice variety (Lo-Zn CR). This study compared TAZ in a polished zinc-biofortified rice (Hi-Zn BfR) compared with Lo-Zn CR. To measure the amount of TAZ by young Bangladeshi children from Hi-Zn BfR, Lo-Zn CR, or CR plus sufficient exogenous zinc fortificant (Lo-Zn CR+Zn) matching the zinc content of Hi-Zn BfR. A total of 47 children 36-59-mo-old were enrolled in a crossover study. On the day 1, children received a Lo-Zn CR diet. On days 2 and 4, group A (n = 23) received 150 g of Lo-Zn CR and group B (n = 24) received 150g of Lo-Zn CR+Zn as part of a mixed diet. On days 3 and 5, both groups received 150 g of Hi-Zn BfR. Fractional zinc absorption (FZA) was measured in all diet periods using a triple-isotope tracer (oral 67-Zn and 70-Zn; intravenous 68-Zn) ratio technique; TAZ was calculated as product of zinc intake [total dietary zinc (TDZ)] and FZA. TDZ was 4.88, 6.14, and 6.70 mg/d when fed Lo-Zn CR-, Lo-Zn CR+Zn-, and Hi-Zn BfR-containing diets, respectively. Mean FZA: 0.23 ± 0.041, 0.169 ± 0.035, and 0.212 ± 0.048 for respective diets (Lo-Zn CR compared with Hi-Zn BfR: P = 0.26; Lo-Zn CR+Zn compared with Hi-Zn BfR: P < 0.001; and Lo-Zn CR compared with Lo-Zn CR+Zn: P < 0.001). Mean TAZ from respective diets were 1.13 ± 0.23, 1.04 ± 0.20, and 1.40 ± 0.33mg/d. TAZ was not significantly different between Lo-Zn CR and Lo-Zn CR+Zn diets (P = 0.52) but was significantly more in Hi-Zn BfR when compared with other 2 diets (P < 0.001 for both). A single-day ration (150 g total) in 3 equally divided servings of Hi-Zn BfR could satisfy 47% of the recommended daily requirement of zinc (3 mg/d) for children 1-3-y old and 28% for children 4-8-y old (5 mg/d) compared with 37% and 23% from Lo-Zn CR for the same age groups, respectively. Hi-Zn BfR is a meaningful component of preventive option for childhood zinc deficiency where rice is staple. This trial was registered at clinicaltrials.gov as NCT04099849.

ABSTRACTProtein and fat concentrations in donor human milk (DHM) can vary twofold to threefold and are influenced by the number of unique donors per pool. The aim of this study was to broadly characterize how the number of donors (2–10) randomly combined into a pool during milk bank processing influenced the variability of macronutrients, vitamins, minerals, and bioactive factors in DHM. The minimum number of donors required for 80% of the pools to meet pre‐defined targets for true protein, fat, and disialyllacto‐N‐tetraose (DSLNT) was also evaluated. Monte Carlo simulation was used to create models that accounted for donor lifetime donation volume and milk bank production constraints. Variability in nutrients was quantified as a Nutrient Inequality Index (NII) which was computed as the ratio of the 90th percentile to the 10th percentile for each simulation. Random multi‐donor pooling of 2–10 donors produced lower variability in DHM macronutrients than most vitamins and minerals. A priori targets of 0.9 g/dL of true protein, 3.5 g/dL of fat, and 210 µg/L of DSLNT could not be achieved with any random pooling scenario. The NII for lactose stabilized at less than 1.1 when there were 3+ donors per pool, while the NII for fat and true protein stabilized at less than 1.3 when there were 5+ donors per pool. The NII exceeded 1.5, even at 10 donors per pool, for several micronutrients including zinc, copper, sodium, iron, biotin, riboflavin, B6, B12, and pantothenic acid.

Somatostatin (Sst) is an inhibitory regulator of many hormones. The prenatal environment impacts an offspring's risk to type 2 diabetes in adulthood. However, the effect of maternal Sst deficiency on glucose and insulin metabolism in offspring and metabolic disease risk in their adult life has been poorly understood. The study was to investigate the impact of a lack of maternal Sst exposure in mouse male and female offspring on diet-induced changes in glucose metabolism and adiposity. Sst knockout offspring, SstKO born to the Sst-heterozygous dams or SstKO-MSD born to the Sst-homozygous dams were fed either a regular diet (CD) or a high-fat diet (HFD) at 3-week-old for 15 weeks. Body weight and blood glucose levels were monitored. Glucose and insulin tolerance tests were performed. Plasma hormone levels and gene expression in the hypothalamus were investigated. The results demonstrated that only male SstKO-MSD offspring developed obesity accompanied by severe insulin and leptin resistance after HFD challenge. Insulin secretion was reduced in both basal and oral glucose-challenged conditions in the CD-fed male SstKO-MSD mice. A reduced ratio of islet area to pancreas area was noted in SstKO-MSD mice in both sexes. Plasma levels of glucagon, Glp1 and Pyy were elevated in both male and female SstKO and SstKO-MSD mice. mRNA expression of leptin receptor, FoxO1, Npy and Agrp was downregulated in male SstKO-MSD mice. These results demonstrate that a lack of fetal somatostatin exposure impairs the islet development in offspring and increases risk of obesity, insulin resistance and leptin resistance later in life.

Immune function is affected by vitamin D status, but the optimal serum 25-hydroxy vitamin D [25(OH)D] concentration for immune function is not known. We hypothesized that 25(OH)D would be associated with markers of inflammation and immune activation. We identified associations between 25(OH)D and immune markers from 361 healthy adults using polynomial regression. Linear regression was used to define the slope (β) of significant linear associations, and piecewise regression identified inflection points (IPs) for curvilinear associations with P < 0.05. IPs with a slope difference (SD) P < 0.05 before and after were significant. 25(OH)D had linear, negative associations with interleukin (IL)-6 (β: -0.126; P = 0.009) and macrophage-derived chemokine (MDC) (β: -0.108; P = 0.04) and a linear, positive association with matrix metalloproteinase (MMP)-1 (β: 0.108; P = 0.04). Among the significant curvilinear associations, 2 showed negative associations below but positive associations above an IP with nearly significant SD P values, including percentage of effector-memory CD8 T cells (IP: 56.2 nmol/L; SD P = 0.067) and platelet concentration (IP: 38.9 nmol/L; SD P = 0.058). The opposite associations, positive below and negative above an IP, were seen for eotaxin (IP: 49.5 nmol/L; SD P = 0.049); interferon (IFN)-γ-induced protein-10 (IP-10) (IP: 71.8 nmol/L; SD P = 0.02); percentage of CD4 T cells expressing programmed cell death protein (PD)-1 (IP: 71.2 nmol/L; SD P = 0.01); percentage of Tregs expressing human leukocyte antigen, DR isotype (HLA-DR) (IP: 67.5 nmol/L; SD P < 0.0001); percentage of memory Tregs (IP: 68.8 nmol/L; SD P = 0.002); and percentage of memory Tregs expressing HLA-DR (IP: 68.8 nmol/L; SD P = 0.0008). These findings are consistent with low vitamin D status allowing and higher vitamin D status dampening inflammation and immune activation. IP analysis identified possible thresholds for vitamin D effects on immune function. Two of 3 IPs at ∼50 nmol/L show higher inflammation below this concentration, suggesting 50 nmol/L as a minimum target for dampening inflammation. IPs at ∼70 nmol/L identify a threshold for CD4 T-cell activity, including Treg activation and IFN-γ-driven production of the T-cell chemokine IP-10, suggesting an optimal concentration for regulating adaptive immunity. This study was registered at clinicaltrials.gov as NCT02367287.