Racial Differences in Eating Patterns and Food Purchasing Behaviors among Urban Older Women

OBJECTIVE

To examine differences in diet and food purchasing behaviors between Black and White older women living in urban neighborhoods.

DESIGN

Cross-sectional observational study.

SETTING

Urban neighborhoods in Washington, DC, USA.

PARTICIPANTS

Community-dwelling White and Black women of age 65 and older.

MEASUREMENTS

Participants were queried on diet via 24-hour recalls, food purchasing habits, their use of neighborhood resources and local travel patterns. Frequency and location of self-reported food purchasing and consumption were compared by race.

RESULTS

In 2014 and 2015, 49 White and 44 Black older women were enrolled in the study. Compared to Whites, Blacks reported lower daily caloric intake (mean (SD) 1314 (404) vs. 1529 (448), p=0.02), with a higher percent of calories from protein and fat 1.8 (7.0), p=0.03), and a slightly higher polyunsaturated to saturated fat ratio (p=0.05). Blacks had substantially lower alternate healthy eating index (AHEI) (33.5 (10.2) vs. 43.9 (10.8) of 80 possible points, p<0.001), daily intake (grams) of total fiber (15.3 (8.1) vs. 22.9 (8.5), p<0.001), insoluble fiber (10.8 (6.9) vs. 15.9 (6.5), p<0.001), and soluble fiber (4.5 (2.0) vs. 6.9 (2.8), p<0.001). Blacks had lower intake of micronutrients, alcohol and caffeine. Blacks shopped for groceries less often (4.4 (3.0) vs. 6.2 (3.0) monthly; p=0.006) and spent a longer time traveling to stores (15.8 (9.1) vs. 11.5 (7.2) minutes per trip, p=0.02). A lower percent of Blacks walked to stores (14% vs. 40%, p=0.003) and a higher percent of Blacks rode in a car with someone else (33% vs. 6%, p<0.001).

CONCLUSIONS

In an urban setting, food consumption and purchasing behaviors differed substantially between older Black and White women, which should be further investigated and considered to promote healthy eating in older populations.

Globular domains of agrin are functional units that collaborate to induce acetylcholine receptor clustering

Agrin, an extracellular matrix protein involved in neuromuscular junction formation, directs clustering of postsynaptic molecules, including acetylcholine receptors (AChRs). This activity resides entirely in the C-terminal portion of the protein, which consists of three laminin-like globular domains (G-domains: G1, G2 and G3) and four EGF-like repeats. Additionally, alternate mRNA splicing yields G-domain variants G2(0,4) with 0- or 4-amino-acid inserts, and G3(0, 8,11,19) with 0-, 8-, 11- or 19-amino-acid inserts. In order to better understand the contributions of individual domains and alternate splicing to agrin activity, single G-domains and covalently linked pairs of G-domains were expressed as soluble proteins and their AChR clustering activity measured on cultured C2 myotubes. These analyses reveal the following: (1) While only G3(8) exhibits detectable activity by itself, all G-domains studied (G1, G2(0), G2(4), G3(0) and G3(8)) enhance G3(8) activity when physically linked to G3(8). This effect is most pronounced when G2(4) is linked to G3(8) and is independent of the order of the G-domains. (2) The deletion of EGF-like repeats enhances activity. (3) Increasing the physical separation between linked G1 and G3(8) domains produces a significant increase in activity; similar alterations to linked G2 and G3(8) domains are without effect. (4) Clusters induced by two concatenated G3(8) domains are significantly smaller than all other agrin forms studied. These data suggest that agrin G-domains are the functional units which interact independently of their specific organization to yield AChR clustering. G-domain synergism resulting in biological output could be due to physical interactions between G-domains or, alternatively, independent interactions of G-domains with cell surface receptors which require spatially localized coactivation for optimal signal transduction.

Immunotoxicology of cigarette smoke condensates: suppression of macrophage responsiveness to interferon gamma

We have investigated systematically the effects of short-term exposure to main stream cigarette smoke condensates (CSC-MS) on basal and inducible functional capacities of murine peritoneal exudate macrophages. Macrophages treated with CSC-MS form granules that fluoresce orange under blue excitation, consistent with the speculation that they are polycyclic aromatic hydrocarbons (PAH). CSC-MS selectively suppressed interferon gamma (IFN gamma) induction of four macrophage functional capacities: enhanced phagocytosis of immunoglobulin-opsonized sheep red blood cells, TPA-induced H2O2 production, class II major histocompatibility complex expression, and nitric oxide synthesis. In contrast, two macrophage functions that are not induced by IFN gamma, basal electron transport and LPS-induced TNF alpha production, were enhanced by treatment with CSC-MS. These results suggest that the suppressive effects of CSC-MS on macrophage responsiveness were selective and were not due to nonspecific inhibition of general functions such as RNA or protein synthesis. Since macrophage responsiveness to IFN gamma can result in induction of functional capacities that are fundamental to immunity, the data suggest that CSC-MS maybe deleterious to the general health of the smoker.