Search tips
Search criteria

Results 1-14 (14)

Clipboard (0)

Select a Filter Below

more »
Year of Publication
Document Types
author:("Ren, jiangxi")
1.  Interaction of Fatty Acid Genotype and Diet on Changes in Colonic Fatty Acids in a Mediterranean Diet Intervention Study 
Cancer prevention research (Philadelphia, Pa.)  2013;6(11):10.1158/1940-6207.CAPR-13-0131.
A Mediterranean diet increases intakes of n-3 and n-9 fatty acids and lowers intake of n-6 fatty acids. This can impact colon cancer risk since n-6 fatty acids are metabolized to pro-inflammatory eicosanoids. The purpose of this study was to evaluate interactions of polymorphisms in the fatty acid desaturase genes, FADS1 and FADS2, and changes in diet on fatty acid concentrations in serum and colon. A total of 108 individuals at increased risk of colon cancer were randomized to either a Mediterranean or a Healthy Eating diet. Fatty acids were measured in both serum and colonic mucosa at baseline and after 6 months. Each individual was genotyped for four single nucleotide polymorphisms in the FADS gene cluster. Linear regression was used to evaluate the effects of diet, genotype and the diet by genotype interaction on fatty acid concentrations in serum and colon. Genetic variation in the FADS genes was strongly associated with baseline serum arachidonic acid (n-6, AA) but serum eicosapentaenoic acid (n-3) and colonic fatty acid concentrations were not significantly associated with genotype. After intervention, there was a significant diet by genotype interaction for AA concentrations in colon. Subjects who had all major alleles for FADS1/2 and were following a Mediterranean diet had 16% lower AA concentrations in the colon after 6 months of intervention than subjects following the Healthy Eating diet. These results indicate that FADS genotype could modify the effects of changes in dietary fat intakes on AA concentrations in the colon.
PMCID: PMC3840911  PMID: 24022589
Fatty acid desaturase; diet-genotype interaction; colon cancer prevention; nutrition
2.  Total Serum Fatty Acid Analysis by GC-MS: Assay Validation and Serum Sample Stability 
Current pharmaceutical analysis  2013;9(4):331-339.
Analysis of n3 fatty acids in serum samples has clinical applications in supplementation trials, but the analysis can be challenging due to low levels, stability issues and intra-individual variation. This study presents the single laboratory validation of a gas chromatographic-mass spectral (GC-MS) assay for analysis of fatty acid methyl esters (FAME) using sensitive single ion monitoring and provides data on fatty acid stability under different sample handling conditions. Recovery of total fatty acids from serum with Folch extraction was optimized and parallelism tests with spiked samples indicated that the serum matrix did not interfere with mass spectral quantitation. Precision and accuracy of the assay at the lowest limit of quantitation and at low, medium and high levels met with accepted guidelines for single laboratory validation. Several storage conditions that can be encountered with clinical samples also were evaluated for impact on fatty acid levels in serum. Serum from blood that was stored refrigerated for 3 days yielded similar results as serum that was prepared and frozen at −80°C immediately. Serum storage at room temperature for 3–24 hours and serum subjected to one freeze/thaw cycle had minimal effects on fatty acid levels. The intra-individual variability in pregnant women was reasonably small, with significant correlation coefficients ranging from 0.35 to 0.76 for blood drawn between 12–20 weeks versus 34–36 weeks of gestation. These results indicate that GC-MS with single ion monitoring is valid for the analysis of total fatty acids in clinical samples, even when blood processing cannot be performed in a timely manner.
PMCID: PMC4123757  PMID: 25110470
Fatty acids; fatty acid methyl esters; GC-MS; fish oils; pregnancy; blood levels
3.  Relationships between Serum and Colon Concentrations of Carotenoids and Fatty Acids in a Randomized Dietary Intervention Trial 
Little is known about dietary effect on colonic nutrient concentrations associated with preventive foods. This study observed 120 persons at increased risk of colon cancer randomized to a Mediterranean versus a Healthy Eating diet for six months. The former targeted increases in whole grains, fruits, vegetables, monounsaturated and n3 fats. Healthy Eating diet was based on Healthy People 2010 recommendations. At baseline, dietary fat and carotenoid intakes were poorly associated (Spearman ρ < 0.4) with serum and colon concentrations. Strong associations were observed between serum and colon measurements of β-cryptoxanthin (ρ = 0.58, p-value < 0.001), α-carotene (ρ = 0.48, p-value < 0.001), and β-carotene (ρ = 0.45, p-value < 0.001). After six months, the Healthy Eating arm increased serum lutein, β- and α-carotene significantly (p-value < 0.05). In the Mediterranean arm the significant increases were in serum lutein, β-cryptoxanthin, β-carotene, monounsaturated and n3 fats. A significant group-by-time interaction (p-value = 0.03) was obtained for monounsaturated fats. Colonic increases in carotenoids and n3 fats were significant only in Healthy Eating arm, while group-by-time interaction were significant for β-carotene (p-value = 0.02), and α-carotene (p-value = 0.03). Changes in colon concentrations were not significantly associated with reported dietary changes. Changes in colon and serum concentrations were strongly associated for β-cryptoxanthin (ρ = 0.56, p-value < 0.001), and α-carotene (ρ = 0.40, p-value < 0.001). The associations between colonic and serum concentrations suggest the potential utility of using serum concentration as a target in dietary interventions aimed at reducing colon cancer risk.
PMCID: PMC4021591  PMID: 23592741
Mediterranean diet; Healthy People diet; Carotenoids; Fatty Acids; Spearman Correlation
4.  The Mothers, Omega-3, and Mental Health Study: a double-blind, randomized controlled trial 
Maternal deficiency of the omega-3 fatty acid, docosahexaenoic acid (DHA), has been associated with perinatal depression, but there is evidence that supplementation with eicosapentaenoic acid (EPA) may be more effective than DHA in treating depressive symptoms. This trial tested the relative effects of EPA- and DHA-rich fish oils on prevention of depressive symptoms among pregnant women at an increased risk of depression.
We enrolled 126 pregnant women at risk for depression (Edinburgh Postnatal Depression Scale score 9–19 or a history of depression) in early pregnancy and randomly assigned them to receive EPA-rich fish oil (1060 mg EPA plus 274 mg DHA), DHA-rich fish oil (900 mg DHA plus 180 mg EPA), or soy oil placebo. Subjects completed the Beck Depression Inventory (BDI) and Mini-International Neuropsychiatric Interview at enrollment, 26–28 weeks, 34–36 weeks, and at 6–8 weeks’ postpartum. Serum fatty acids were analyzed at entry and at 34–36 weeks’ gestation.
One hundred eighteen women completed the trial. There were no differences between groups in BDI scores or other depression endpoints at any of the 3 time points after supplementation. The EPA-and DHA-rich fish oil groups exhibited significantly increased post-supplementation concentrations of serum EPA and serum DHA respectively. Serum DHA- concentrations at 34–36 weeks were inversely related to BDI scores in late pregnancy.
EPA-rich fish oil and DHA-rich fish oil supplementation did not prevent depressive symptoms during pregnancy or postpartum.
PMCID: PMC4010222  PMID: 23531328
depression; docosahexaenoic acid; eicosapentaenoic acid; fish oil; supplementation
5.  A Mediterranean Dietary Intervention in Persons at High Risk of Colon Cancer: Recruitment and Retention to an Intensive Study Requiring Biopsies 
Contemporary clinical trials  2012;33(5):881-888.
This study recruited persons at increased risk of colon cancer to an intensive dietary intervention study that required biopsies of the colon by flexible sigmoidoscopy at baseline and after six months of intervention. A total of 1314 individuals contacted the study, and only 16 individuals indicated that the sigmoidoscopy procedure was an obstacle to study participation. A total of 270 individuals completed a screening visit and signed a screening consent form. Inquiries about the study tended to be fewer in the winter and late summer. Failure to return food records was the most common reason for exclusion. Dietary recall at enrollment indicated that subjects were consuming significantly more vegetables, lower sodium and a lower glycemic load on the day before starting the study versus during the eligibility phase which might have an impact on biomarker measures. This makes it important to capture dietary changes in the period between determination of eligibility and enrollment. Subjects (n=120) were randomized to follow a Healthy Eating or a Mediterranean Diet, each of which required substantial dietary record-keeping. The study completion rate was 78%, and subjects reported high satisfaction with study participation. Of the 93 individuals who completed the study, only one refused the flexible sigmoidoscopy at the final visit. These findings suggest that flexible sigmoidoscopy does not appear to be a barrier for recruitment of high-risk individuals to an intensive dietary intervention trial, but that completing food records can be.
PMCID: PMC3408796  PMID: 22640923
colon biopsy; recruitment; dietary intervention; cancer prevention
Dietary ω3 fatty acids can modulate substrate availability for cyclooxygenases and lipoxygenases, thus modulating downstream eicosanoid formation. This could be an alternative approach to using NSAIDs and other COX inhibitors for limiting PGE2 synthesis in colon cancer prevention. The aims of this study were to evaluate to what extent cyclooxygenase- and lipoxygenase-derived products could be modulated by dietary fish oil in normal colonic mucosa, and to evaluate the role of COX-1 and COX-2 in formation of these products. Mice (wild-type, COX-1 null, or COX-2 null) were fed a diet supplying a broad mixture of fatty acids present in European/American diets, supplemented with either olive oil (oleate control diet) or menhaden (fish) oil ad libitum for 9–11 wk. Colonic eicosanoid levels were measured by LC-MS/MS, and proliferation was assessed by Ki67 immunohistochemistry. Dietary alteration of colonic arachidonic acid: eicosapentaenoic ratios resulted in large shifts in formation of cyclooxygenase and lipoxygenase metabolites. COX-1 knockout virtually abolished PGE2 formation but interestingly 12-HETE and 15-HETE formation was increased. The large changes in eicosanoid profiles were accompanied by relatively small changes in colonic crypt proliferation, but such changes in eicosanoid formation might have greater biological impact upon carcinogen challenge. These results indicate that in normal colon, inhibition of COX-2 would have little effect on reducing PGE2 levels.
PMCID: PMC3246564  PMID: 21937210
colon cancer; fish oil; cyclooxygenase; prostaglandin E2; hydroxyeicosatetraenoic acids; EPA
7.  Lifestyle Factors Associated with Serum N-3 Fatty Acid Levels in Breast Cancer Patients 
Breast (Edinburgh, Scotland)  2012;21(4):608-611.
Long chain n3 fatty acids appear to have beneficial effects in several domains of health relevant to breast cancer survivors. This study evaluated inter-individual differences in serum levels of n3 fatty acids in 40 breast cancer patients who were participating in a pilot study for prevention of weight gain. Significant predictors of baseline n3 fatty acid levels in serum were dietary intakes of n3 fatty acids, BMI, serum levels of carotenoids and TV hours watched/day, accounting for 43% of the variance. Counseling for prevention of weight gain also tended to increase n3 fatty acid blood levels over time during chemotherapy.
PMCID: PMC3368994  PMID: 22377591
obesity; breast cancer; diet; physical activity; omega 3 fatty acids; n3 fatty acids
8.  MicroRNA-224 Targets SMAD Family Member 4 to Promote Cell Proliferation and Negatively Influence Patient Survival 
PLoS ONE  2013;8(7):e68744.
MicroRNA-224 (miR-224) is frequently over-expressed in liver and colorectal cancers. We and others have previously described the role of miR-224 over-expression in cell proliferation in vitro but we have yet to identify the relevant miR-224 direct target. In this study, we further demonstrated that miR-224 up-regulation promotes cell proliferation using both in vitro assays and in vivo tumor growth models. We systematically screened for high confidence miR-224 targets by overlapping in silico predicted targets from multiple algorithms and significantly down-regulated genes in miR-224-expressing cells from whole genome expression microarrays. A total of 72 high confidence miR-224 targets were identified and found to be enriched in various cancer-related processes. SMAD family member 4 (SMAD4) is experimentally validated as the direct cellular target through which miR-224 promotes cell proliferation. The clinical relevance of our experimental observations was supported by a statistically significant inverse correlation between miR-224 and SMAD4 transcript expression in tumor versus paired adjacent non-tumorous tissues from HCC patients (p<0.001, r = −0.45, R2 = 0.122). Furthermore, miR-224 up-regulation and SMAD4 down-regulation is significantly associated with poorer patient survival (p<0.05). In summary, miR-224/SMAD4 pathway is a clinically relevant pathway to provide new insights in understanding HCC. (191 words).
PMCID: PMC3726696  PMID: 23922662
9.  A randomized controlled trial of long term effect of BCM guided fluid management in MHD patients (BOCOMO study): rationales and study design 
BMC Nephrology  2012;13:120.
Bioimpedance analysis (BIA) has been reported as helpful in identifying hypervolemia. Observation data showed that hypervolemic maintenance hemodialysis (MHD) patients identified using BIA methods have higher mortality risk. However, it is not known if BIA-guided fluid management can improve MHD patients’ survival. The objectives of the BOCOMO study are to evaluate the outcome of BIA guided fluid management compared with standard care.
This is a multicenter, prospective, randomized, controlled trial. More than 1300 participants from 16 clinical sites will be included in the study. The enrolment period will last 6 months, and minimum length of follow-up will be 36 months. MHD patients aged between 18 years and 80 years who have been on MHD for at least 3 months and meet eligibility criteria will be invited to participate in the study. Participants will be randomized to BIA arm or control arm in a 1:1 ratio. A portable whole body bioimpedance spectroscopy device (BCM—Fresenius Medical Care D GmbH) will be used for BIA measurement at baseline for both arms of the study. In the BIA arm, additional BCM measurements will be performed every 2 months. The primary intent-to-treat analysis will compare outcomes for a composite endpoint of death, acute myocardial infarction, stroke or incident peripheral arterial occlusive disease between groups. Secondary endpoints will include left ventricular wall thickness, blood pressure, medications, and incidence and length of hospitalization.
Previous results regarding the benefit of strict fluid control are conflicting due to small sample sizes and unstable dry weight estimating methods. To our knowledge this is the first large-scale, multicentre, prospective, randomized controlled trial to assess whether BIS-guided volume management improves outcomes of MHD patients. The endpoints of the BOCOMO study are of utmost importance to health care providers. In order to obtain that aim, the study was designed with very careful important considerations related to the endpoints, sample size, inclusion criteria, exclusion criteria and so on. For example, annual mortality of Beijing MHD patients was around 10%. To reach statistical significance, the sample size will be very large. By using composite endpoint, the sample size becomes reasonable and feasible. Limiting inclusion to patients with urine volume less than 800 ml/day the day before dialysis session will limit confounding due to residual renal function effects on the measured parameters. Patients who had received BIS measurement within 3 months prior to enrolment are excluded as data from such measurements might lead to protocol violation. Although not all patients enrolled will be incident patients, we will record the vintage of dialysis in the multivariable analysis.
Trial registration
Current Controlled Trials NCT01509937
PMCID: PMC3489516  PMID: 23006960
Hemodialysis; Bioimpedance; Dry weight; Body composition monitor; Randomized controlled trial
Nutrition and cancer  2011;64(1):163-172.
The balance of putative pro- and anti-inflammatory lipoxygenase (LOX)-derived S-hydroxyeicosatetraenoic acids (S-HETEs) in colon mucosa is a potential target for modulating colon cancer risk and progression. The biological effects of S-HETEs and R-HETEs (produced by distinct pathways) may differ, but levels of these compounds in colon are unknown. The objective of this study was to develop chiral methods to characterize HETE enantiomers in colonic mucosa and evaluate the effects of fish oil on HETE formation. C57BL/6 mice (COX-1 null, COX-2 null, wild-type) were fed a diet supplemented with either olive oil or menhaden oil for 11 weeks, and R/S-HETEs in colonic mucosa were quantified by chiral LC-MS/MS. The R-enantiomer comprised 60-72% of 5-HETE, 18-58% of 15-HETE and 1-16% of 12-HETE in colonic mucosa, suggesting that non-LOX sources contribute to HETE profiles. Fish oil reduced levels of both R- and S-HETEs, and increased the preponderance of the R-enantiomers (particularly 12- and 15-HETEs). There was apparent shunting of arachidonic acid to12/15-LOX in the COX-1 null animals. This is the first report of the enantiomeric composition of HETEs in the colon in vivo.
PMCID: PMC3410550  PMID: 22149144
experimental; lipoxygenase; hydroxyeicosatetraenoic acid; enantiomer; colon
11.  A Diet and Exercise Intervention during Chemotherapy for Breast Cancer 
The open obesity journal  2011;3:87-97.
Weight gain is an important concern that impacts on breast cancer outcomes and general health in survivorship. This randomized, pilot study evaluated whether or not women could comply with a weight control program that is initiated at the beginning of chemotherapy for breast cancer. The program sought to prevent weight gain using a low-fat, high fruit-vegetable diet combined with moderate physical activity. The intervention was implemented using a telephone counseling approach that blended motivational interviewing with social cognitive theory. A total of 40 women were recruited over 9 months at the University of Michigan Comprehensive Cancer Center. This represents 55% of eligible women referred to the study and indicates that interest in a healthy lifestyle program at the initiation of chemotherapy for breast cancer was high. Subjects who dropped out had significantly lower fruit and vegetable intakes and lower blood carotenoids at baseline than subjects who completed the study. Statistically significant beneficial effects were observed on fruit and vegetable intakes, physical activity and breast cancer-specific well-being by the intervention. Mean body fat from dual energy X-ray absorptiometry increased in the written materials arm and decreased in the intervention arm. Of the enrolled women, 75% completed 12 months on study and satisfaction with study participation was high. These data indicate that lifestyle intervention during breast cancer treatment is feasible during treatment with chemotherapy for breast cancer and benefits women in several domains.
PMCID: PMC3253619  PMID: 22238561
obesity; breast cancer; diet; physical activity; weight gain
12.  Obesity is Associated with Atypia in Breast Ductal Lavage of Women with Proliferative Breast Disease 
Cancer epidemiology  2009;33(3-4):242-248.
Benign proliferative breast disease without atypia slightly increases breast cancer risk but there are currently few clinical options for breast cancer prevention in this group of women.
We conducted a pilot study of women with a past diagnosis of proliferative breast disease with a goal to determine if the characteristics of cells obtained by breast ductal lavage were related to nutritional factors.
There were 57 women who enrolled. A total of 39 women yielded nipple aspirate fluid (NAF) samples and 36 underwent breast ductal lavage. Five of the lavage samples were acellular and 28 had at least 200 cells. Surprisingly, atypia was present in 11 women. Presence of atypia was associated with slight changes in morphometric features of the epithelial cells such as measures of circularity) as obtained by image analysis, but the only variable significantly different in women with atypia (versus no atypia) was a higher mean body mass index. Body mass index also was significantly correlated with C-reactive protein (CRP) levels in the nipple aspirate fluid, indicating that obesity might have a pro-inflammatory effect on the breast that can contribute to increased rates of atypia.
Although the clinical significance of atypia in breast ductal lavage is uncertain, these results support further work on prevention of obesity as a strategy for reducing breast cancer risk.
PMCID: PMC2763034  PMID: 19683484
proliferative breast disease; nuclear morphometry; breast ductal lavage; obesity
13.  A randomized feasibility trial of brief telephone counseling to increase fruit and vegetable intakes 
Preventive medicine  2010;50(5-6):265-271.
This study examined the feasibility of eliciting dietary changes in subjects recruited from a diverse primary care setting in Michigan using a written, one-page plan, either alone or with telephone counseling.
A total of 96 subjects were enrolled from 9/28/06 to 5/7/07 (49% minorities). Subjects were randomized into three groups. Group 1 received written materials. Group 2 received written materials plus a one-page form that asked them to make a specific daily plan for substituting one less nutritious food with two servings of fruits and vegetables. Group 3 received the written materials, the one-page form and telephone counseling from a dietitian.
Subject retention was 76% for the 12-week study. Subjects in Groups 1, 2 and 3 changed their mean intakes of fruit and vegetables by 0.4, −0.7 and 1.4 servings/day, respectively. Participants in Group 3 lost an average of 0.73 kg, increased their perception of the importance of eating fruits and vegetables, and 63% increased their serum levels of carotenoids by 20% or more.
Recruitment through a primary care clinic was effective. Formulation of a written plan combined with telephone counseling appears to be promising for improving fruit and vegetable intakes and warrants more definitive study.
PMCID: PMC2904076  PMID: 20226809
Diet; Prevention and control; Carotenoids; Behavior therapy
14.  A Mediterranean Dietary Intervention in Healthy American Women Changes Plasma Carotenoids and Fatty Acids in Distinct Clusters 
This study examined patterns of changes in plasma fatty acids and carotenoids when women were asked to follow a novel, Greek-Mediterranean exchange list diet. A total of 69 healthy, non-obese, women ages 25–59, were randomized to either continue their own usual diet or to follow a modified Mediterranean diet for six months. There were no significant changes in blood lipids, triacylglycerol, insulin, glucose or C-reactive protein. Mean plasma carotenoids increased by 55%, which is consistent with a large increase in fruit and vegetable consumption. Likewise, changes in fat intakes were reflected in blood fatty acids, with a 25% increase in mean plasma monounsaturated fatty acids (MUFA). Principal component analysis was conducted to examine the sources of inter-individual variation for changes in carotenoid and fatty acid levels. Changes in the Mediterranean diet were clustered together in four components that accounted for 78% of the variance in plasma levels. Increases in plasma lutein, α- and β-carotene clustered together in a “vegetable” pattern, and increases in carotenoids found in fruit, β-cryptoxanthin and zeaxanthin, also clustered together but accounted for less of the variance. Increases in plasma MUFA were clustered with a decrease in plasma polyunsaturated fatty acids, consistent with substitution in the type of oils consumed. The only association of fatty acid levels with carotenoids was that of lycopene, which clustered together with an increase in saturated fatty acids. The changes in blood levels indicate the exchange list diet was effective for targeting Mediterranean nutrient intakes using foods available in the United States.
PMCID: PMC2735788  PMID: 19358929
cancer prevention; monounsaturated fat; fruit; vegetables; olive oil; human; clinical trial; carotenoids

Results 1-14 (14)