Immunomodulatory molecules are released from the first trimester and term placenta via exosomes

The semiallogenic fetus is tolerated by the maternal immune system through control of innate and adaptive immune responses. Trophoblast cells secrete nanometer scale membranous particles called exosomes, which have been implicated in modulation of the local and systemic maternal immune system. Here we investigate the possibility that exosomes secreted from the first trimester and term placenta carry HLA-G and B7 family immunomodulators. Confocal microscopy of placental sections revealed intracellular co-localization of B7-H1 with CD63, suggesting that B7-H1 associates with subcellular vesicles that give rise to exosomes. First trimester and term placental explants were then cultured for 24 h. B7H-1 (CD274), B7-H3 (CD276) and HLA-G5 were abundant in pelleted supernatants of these cultures that contained microparticles and exosomes; the latter, however, was observed only in first trimester pellets and was nearly undetectable in term explant-derived pellets. Further purification of exosomes by sucrose density fractionation confirmed the association of these proteins specifically with exosomes. Finally, culture of purified trophoblast cells in the presence or absence of EGF suggested that despite the absence of HLA-G5 association with term explant-derived exosomes, it is present in exosomes secreted from mononuclear cytotrophoblast cells. Further, differentiation of cytotrophoblast cells reduced the presence of HLA-G5 in secreted exosomes. Together, the results suggest that the immunomodulatory proteins HLA-G5, B7-H1 and B7-H3, are secreted from early and term placenta, and have important implications in the mechanisms by which trophoblast immunomodulators modify the maternal immunological environment.

Dietary supplement use in the context of health disparities: cultural, ethnic and demographic determinants of use

Women of African American, Hispanic, Asian, Pacific Islander, Native American and Alaskan descent constitute 29% of the female population in the United States but they experience health problems disproportionately. Compared with white women as a group, they are in poorer health and use fewer health services. We know from recent studies that the daily use of multivitamins has been associated with lower risk of coronary disease, colon cancer and breast cancer, particularly for alcohol drinkers. In addition, daily multivitamin and multimineral usage by the elderly can reduce the number of days of illness due to infections by 50%. However, supplement use among women tends to be more prevalent among the middle and older age categories; white, well-educated and higher income women; and those residing in the western part of the United States. This examination of the current health disparities and usage patterns indicates that the women who could benefit most from supplements are not typical users. Qualitative data collected on iron and folic acid supplementation programs in developing countries indicate that diverse cultural practices, attitudes and beliefs among vulnerable populations may influence supplement use. However, data in the U.S literature that describe these factors by culture or ethnicity are sparse. If we are to promote dietary supplements to women who are most vulnerable, more research is warranted in the area of health beliefs, attitudes and sociodemographic determinants of supplement use by culture and or ethnicity, particularly among underprivileged groups.

Pill count adherence to prenatal multivitamin/mineral supplement use among low-income women

In the United States, the prevalence of third trimester anemia among low-income pregnant women is 29% and has not improved since the 1980s. Although low adherence has been linked to the ineffectiveness of iron supplementation programs, data regarding adherence to supplementation in low-income women are currently lacking. Hence this study was conducted to better understand the factors associated with adherence to the use of iron-containing prenatal multivitamin/mineral supplements among low-income pregnant women. Adherence to supplement use was assessed by pill counts among 244 pregnant women of 867 women who were initially randomized to receive 1 of 3 prenatal supplements. All women received care at a public prenatal clinic. Maternal characteristics associated with adherence were identified using predictive modeling. Women took 74% of supplements as prescribed. Adherence was higher among non-Hispanic white women than among non-Hispanic black women (79% vs. 72%, P </= 0.01). Interactions of ethnicity with age group, smoking status, and prior supplement use were significant. Multivariate regression analysis stratified by ethnicity revealed that among the white women education beyond high school, unmarried status, nulligravidity, and smoking were positively associated with adherence. In contrast, among the black women, supplement use 3 mo prior to current pregnancy and no loss of appetite were positively associated with adherence. Further research investigating the influence of cultural factors is necessary to better understand adherence to supplement use and the differences in adherence among ethnic groups.

Correction for errors in measuring adherence to prenatal multivitamin/mineral supplement use among low-income women

Adherence to prenatal multivitamin/mineral supplement use is often measured by self-reports or pill counts. Although both measures were shown to overestimate adherence, measurement error is rarely considered. In this study, we examined measurement error in adherence to prenatal supplement use among pregnant women and demonstrated a calibration method to adjust for error. In a validation subsample (n=51) from a larger clinical study of supplementation, adherence was assessed by self-reports, pill counts, and a Medication Event Monitoring System (MEMS) bottle cap that recorded the date and time of each opening of the pill bottle. Mean adherence in the validation sample as measured by the MEMS (the gold standard) was 68%; thus, adherence measured by self-report (77%) and pill count (84%) reflected overestimation. The Pearson correlation coefficients of self-reports and pill counts to MEMS were 0.35 and 0.62, respectively. When adherence was defined as taking >or=75% of the pills prescribed, sensitivity and specificity were greater for pill counts (93 and 52%, respectively) than for self-reports (88 and 44%). The regression coefficient for pill count adherence from a linear regression on MEMS adherence was applied to pill counts from a larger sample (n=244). The adjustment significantly lowered the estimate of adherence from 74 to 64% (P<0.001) in this larger sample. In conclusion, our data show that both self-reports and pill counts overestimate adherence and that linear regression in comparison to an external standard such as MEMS can be used to correct for measurement error in adherence.

Expression and role of matrix metalloproteinases MMP-2 and MMP-9 in human spinal column tumors

Matrix metalloproteinases (MMPs) have been implicated in the process of tumor invasion and metastasis formation. Thus, we determined the expression of MMPs in various primary and metastatic spinal tumors in order to assess the role of these enzymes in spinal invasion. MMP expression was examined by immunohistochemical localization, and quantitative evaluation of MMP protein content was determined by enzyme-linked immunosorbant assay (ELISA) and Western blotting. MMP enzyme activity was determined by gelatin zymography. Lung carcinomas and melanomas metastatic to the spine were shown to have higher levels of MMP-9 activity than those of breast, thyroid, renal metastases and primary spinal tumors. Immunohistochemical analysis revealed similar difference in expression of MMP-9 in tissue samples. When the tissue samples were subjected to gelatin zymography for examination of MMP-2 and MMP-9 activity and to ELISA and Western blotting for quantitative estimation of protein content, the most striking results were obtained for lung carcinomas and melanomas relative to the other tumors. Lung carcinomas and melanomas metastatic to the spine had considerably higher levels of MMP-9 activity than those of primary spinal tumor or breast, thyroid, and renal carcinoma metastases. Within the metastatic tumor category, neoplasms that are known to be associated with the shortest overall survival rates and most aggressive behavior, such as lung carcinomas and melanomas, had the highest levels of MMP-2 and MMP-9 activity compared to those less aggressive metastatic tumors such as breast, renal cell, and thyroid carcinomas. Our results suggest that MMPs may contribute to the metastases to the spinal column, and overexpression of these enzymes may correlate with enhanced invasive properties of both primary and metastatic spinal tumors.

Morphological and biochemical changes in gastric mucosa of aging rats

Although previous data from this laboratory have indicated that aging is associated with increased gastric mucosal proliferative activity, no direct assessment of proliferative potential of the tissue has been made during aging. In order to assess this, and to determine whether changes in mucosal proliferative potential would be reflected in growth of the tissue, we have examined the labeling index (LI), height and morphology of the gastric mucosa in young (4-month-old) and aged (24-month-old) Fischer-344 rats. In addition, tyrosine kinase (Tyr-k) activity and the levels of phosphotyrosine proteins were determined to evaluate their relationship to mucosal proliferative activity. Histologic evaluation revealed a marked atrophy of the mucosal glandular component with 32% reduction in height in aged rats when compared with young animals. In aged rats, there was also a decrease in gland density, resulting in a reduction in the number of epithelial cells of all types with evidence of decreased secretory activity. Despite the occurrence of mucosal atrophy in aged rats, LI in these animals was significantly increased by 28%. This was associated with a parallel rise in mucosal Tyr-k activity, and a two- to threefold increase in the relative concentrations of seven phosphotyrosine membrane proteins with Mr of 120, 105, 90, 60, 55, 48 and 32 kDa. We conclude that (1) although aging is associated with increased gastric mucosal proliferative activity, this does not result in mucosal growth and that (2) Tyr-k and tyrosine phosphorylation of certain proteins play a role in the regulation of gastric mucosal cell proliferation during aging.

Use of trans fat information on food labels and its determinants in a multiethnic college student population

OBJECTIVES

To examine the correlates of trans fat knowledge and trans fat label use; to examine the influence of trans fat knowledge, trans fat label use, and dietary attitudes on intake of high trans fat food.

DESIGN

Cross-sectional survey.

SETTING

An urban commuter college.

SUBJECTS

Two hundred twenty-two college students.

VARIABLES MEASURED

Trans fat knowledge, food label use, high trans fat food consumption, dietary attitudes, and sociodemographic factors.

ANALYSIS

Chi-square tests and multivariate logistic regression analysis assessed relationships between trans fat knowledge, trans fat label use, and consumption of high trans fat food.

RESULTS

Thirty-seven percent of participants reported never using trans fat information on food labels. Males and minority ethnic groups were less likely to report always using trans fat label information and displayed lower trans fat knowledge compared to females and non-Hispanic whites, respectively. Trans fat knowledge and importance of eating a low-fat diet were positively associated with both food label use and use of trans fat information on food labels. Nonuse of food labels and trans fat information on food labels were associated with higher consumption of fried food.

CONCLUSIONS AND IMPLICATIONS

Trans fat education and promotion of food label use is needed in college students, especially in high-risk groups such as males and ethnic minorities.

Modulation of endothelial cell morphogenesis in vitro by MMP-9 during glial-endothelial cell interactions

The purpose of this study was to investigate the roles of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the formation of capillary structures by human brain microvascular endothelial cells cocultured with SNB19 glioblastoma cells. Unstimulated cocultures did not form capillaries and produce MMP-9 but stimulation with the protein kinase C (PKC) activator 4-phorbol-12-myristate 13-acetate (PMA) produced MMP-9 and capillary networks. Addition of recombinant MMP-9 increased capillary formation. Anti-MMP-9 antibodies, TIMP-1, the synthetic MMPs inhibitor Batimastat (BB-94), and the PKC inhibitor calphostin-C all reduced MMP-9 activity and capillary network formation in these cocultures. Cytochalasin-D in the presence of PMA suppressed MMP-9 expression and capillary formation, but colchicine-B had no such effect. Finally, PMA-induced MMP-9 expression and capillary formation were inhibited by the MEKK-specific inhibitor PD98059. These results suggest that MMP-9 is important in endothelial cell morphogenesis and the formation of capillaries in glial/endothelial cocultures in vitro.

Trophoblast Glycoprotein (TPGB/5T4) in Human Placenta: Expression, Regulation, and Presence in Extracellular Microvesicles and Exosomes

BACKGROUND

Many parallels exist between growth and development of the placenta and that of cancer. One parallel is shared expression of antigens that may have functional importance and may be recognized by the immune system. Here, we characterize expression and regulation of one such antigen, Trophoblast glycoprotein (TPGB; also called 5T4), in the placenta across gestation, in placentas of preeclamptic (PE) pregnancies, and in purified microvesicles and exosomes.

METHODS

Trophoblast glycoprotein expression was analyzed by real-time reverse transcription-polymerase chain reaction (RT-PCR), Western blot, and immunohistochemistry. Regulation of 5T4 in cytotrophoblast cells was examined under either differentiating conditions of epidermal growth factor or under varying oxygen conditions. Microvesicles and exosomes were purified from supernatant of cultured and perfused placentas.

RESULTS

Trophoblast glycoprotein expression was prominent at the microvillus surface of syncytiotrophoblast and on the extravillous trophoblast cells, with minimal expression in undifferentiated cytotrophoblasts and normal tissues. Trophoblast glycoprotein expression was elevated in malignant tumors. In cytotrophoblasts, 5T4 was induced by in vitro differentiation, and its messenger RNA (mRNA) was increased under conditions of low oxygen. PE placentas expressed higher 5T4 mRNA than matched control placentas. Trophoblast glycoprotein was prominent within shed placental microvesicles and exosomes.

CONCLUSION

Given the potential functional and known immunological importance of 5T4 in cancer, these studies reveal a class of proteins that may influence placental development and/or sensitize the maternal immune system. In extravillous trophoblasts, 5T4 may function in epithelial-to-mesenchymal transition during placentation. The role of syncytiotrophoblast 5T4 is unknown, but its abundance in shed syncytial vesicles may signify route of sensitization of the maternal immune system.

Food label use and food label skills among immigrants from the former Soviet Union

OBJECTIVE

To assess food label use and skills and to identify their correlates among immigrants from the former Soviet Union (FSU).

DESIGN/SETTING/PARTICIPANTS

Cross-sectional survey of a convenience sample of 200 FSU immigrants residing in New York City.

VARIABLES MEASURED

Food label use and skills; acculturation; and socioeconomic and psychosocial factors.

ANALYSIS

Chi-square tests and multivariate logistic regression analysis assessed relationships among the outcomes and socioeconomic and other characteristics.

RESULTS

Fifty-five percent reported using food labels always/often; only 32% had good label skills. FSU immigrants particularly had difficulty understanding servings per package and percent daily value. Food label use was significantly associated with factors such as positive attitude toward food labels, and importance of recommendations such as avoiding too much salt and saturated fat. However, these factors were not related to food label skills, which was positively associated with longer residency in the United States (> 7 y).

CONCLUSIONS AND IMPLICATIONS

There is a need for nutrition education among FSU immigrants to increase their food label use and skills to promote healthful food selection. Developers of new food labels should consider ways to present percent daily value and servings per package in a more consumer-friendly manner. Simplifying the presentation of this information could improve food label skills in FSU immigrants, among others.

Tetrahydrofuran: two-generation reproduction toxicity in Wistar rats by continuous administration in the drinking water

In a two-generation reproduction toxicity study, 25 male and 25 female Wistar rats per dose group and generation were exposed continuously to tetrahydrofuran in the drinking water for at least 70 days prior to and during mating, gestation, parturition and lactation to weaning, at concentrations of 0, 1000, 3000 or 9000 ppm (approximately 100, 300 and 700 mg/kg/day in males and females premating, 100, 300 and 800 mg/kg/day in females during gestation, and 200, 500 and 1300 mg/kg/day in females during lactation) through two successive generations. In both generations and sexes, water consumption was dose-relatedly reduced at all doses; food consumption and body weight were reduced at 9000 ppm. Necropsy kidney weights were increased in 9000 ppm F0 males. Pup body weight gain during lactation was reduced in both generations (F1 and F2 pups) and eye opening delayed in the first generation (F1 pups) at 9000 ppm; there were no treatment-related malformations. The NOAEL of tetrahydrofuran in drinking water is 9000 ppm for parental fertility and reproductive performance, and 3000 ppm for systemic parental and developmental toxicity.

Expression and localization of urokinase-type plasminogen activator in human spinal column tumors

We have sought to determine the production and activity of serine proteases in primary and metastatic spinal tumors and the association of these enzymes with the invasive and metastatic properties of spinal column tumors. Using immunohistochemical techniques, the cellular localization and expression of urokinase-type plasminogen activator (uPA) was assessed, whereas its activity was determined by fibrin zymography, and the amounts of enzyme were measured by an enzyme-linked immunosorbent assay (ELISA) in primary spinal column tumors (chordoma, chondrosarcoma, and giant cell tumor) and metastatic tumors of the spine arising from various malignancies (breast, lung, thyroid, and renal cell carcinomas, and melanomas). Metastatic tumors displayed higher levels of uPA activity than did primary spinal tumors (P<0.001). Immunohistochemical analysis revealed that uPA expression was highest in metastases from lung and breast carcinomas and melanomas, followed by metastatic tumors from thyroid and renal cell carcinomas. Similar results were obtained for uPA activity and enzyme level as determined by fibrin zymography and ELISA, respectively. We conclude that metastatic spinal tumors possess higher levels of uPA expression and activity than the primary spinal tumors, which tend to be less aggressive and only locally invasive malignancies. The results suggest that the plasminogen system may participate in the metastasis of tumors to the spinal column.

Acculturation, Food Label Literacy and Use Among South Asian Americans

Objectives

To examine the level of acculturation and its association with food label literacy and use among South Asian Americans.

Methods

Data were collected using an online cross-sectional survey of 269 South Asian Americans living across the United States, recruited via social media and snow-ball sampling method. The Short Acculturation Scale for Hispanics was adapted to measure acculturation amongst South Asian adults. The Newest Vital Sign health literacy assessment tool was used to measure food label literacy.

Results

In this sample of 196 South Asian Americans with complete data, mean age was 36 ± 11.4 y, the majority were born outside the U.S (84%), women (69%), married (69%), overweight/obese (65%) and had college degrees (86%). While most (82%) reported using food labels at least sometimes when purchasing a food product for the first time (82%), and that food labels influenced their purchase decisions (75%), only 35% demonstrated food label literacy (with maximum food label literacy score). Older (age ≥ 36y) South Asian Americans were more likely to be food label users (89.4% vs 73.6%, P = .006) and to report that food labels influence their food purchases (82.8% vs 69%, P = .034) than their younger counterparts. Mean acculturation was 3.14 ± 0.78 (scale 1 – 5). Higher acculturation (score &gt;median) was not associated with food label use, but was significantly associated with food label literacy (43.6% vs 27.3%, P = 0.018). The association between higher acculturation and food label literacy remained significant after controlling for age, sex and education (adj OR = 2.22; 95% CI: 1.18, 4.14).

Conclusions

Nutrition education interventions are needed to improve food label literacy among South Asian Americans.

Funding Sources

None.

Gender, acculturation, food patterns, and overweight in Korean immigrants

OBJECTIVE

To describe acculturation, food patterns, overweight, and gender differences among Korean immigrants in the United States.

METHODS

A cross-sectional exploratory survey assessed acculturation, food frequencies, and weight status of 195 Korean immigrants.

RESULTS

Acculturated Korean immigrants (score ≥2.5) were more likely to consume both healthy and unhealthy US foods. Acculturation was not associated with overweight. Men were more likely to be acculturated (OR=2.46; CI=1.26-4.79) and overweight (OR=5.08; CI=2.37-10.90) than women. Moreover, overweight men reported more frequent consumption of fast foods, hot dogs (OR=2.92;CI=1.18-7.22), and tacos (OR=4.12;CI=1.60-10.62) than did nonoverweight men.

CONCLUSION

Dietary interventions in Korean immigrants should take gender differences in acculturation and food patterns into account.

Food Insecurity Prevalence and Correlates in a Diverse Urban College Student Population (P04-054-19)

Objectives

To estimate the prevalence of food insecurity and to examine its correlates among students at an urban commuter-college.

Methods

Cross-sectional survey of 450 students enrolled at an urban commuter-college. Chi-square test was used to assess differences in socio-demographics characteristics, overweight/obesity status, fruit and vegetable consumption and perceived stress by food security level.

Results

Among students surveyed, 25.6% were food insecure with 12.2% having low food security and 13.3% having very low food security. The rate of food insecurity was significantly higher in black (55.6%) and Hispanic (52.7%) students compared to white (17.7%) and Asian (28.2%) students (P < 0.01). Older students (25–40 y) were also more likely to be food insecure than younger (≤ 25 y) students (42.5% vs. 28.1%; P = 0.02). There were no significant differences in fruit and vegetable consumption, overweight/obese status or perceived stress among food secure and food insecure students.

Conclusions

Food insecurity was found to be a prevalent problem in this sample, particularly in older, Black and Hispanic students. Colleges and universities must provide options and resources for low-income students to help increase access to and affordability of nutritious foods.

Funding Sources

“This material is based upon work that is supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number ____________. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.”