bluuebunny/crossref_metadata_2025 huggingface dataset:
Cranberry flavonols inhibit matrix metalloproteinase activity in human prostate cancer cells
Authors: Hurta Robert , MacPhee James , Elwood Benjamin , Patel Kunal , Neto Catherine
Published: June 2021

This study examined the effects of a flavonol‐enriched fraction (FL) from cranberry (V. macrocarpon) on MMP activity in DU145 cells. FL was characterized to contain quercetin and myricetin derivatives. MMP‐2/‐9 activity (assessed by zymography) was inhibited by FL. FL (50 ug/mL) decreased cellular viability by 15 % post 6 hours of treatment. The effect of FL treatment on protein modulators of MMPs was evaluated. Treatment of DU145 cells with 50 ug/mL FL for 6 hours resulted in increased expression of TIMP‐2, decreased expression of TIMP‐1 with no change in either EMMPRIN or RECK. The effect of FL on cell signaling proteins was evaluated. FL treatment decreased the expression of p‐ERK, p‐p38 and increased p38 with no change in ERK 1/2 protein levels. JNK‐1, p‐JNK‐2 and pJNK‐1 increased in response to FL treatment., and JNK‐2 was unchanged. AKT protein levels were unchanged following FL treatment while p‐AKT levels decreased. PI3K p85 levels decreased and PI3K p110 levels increased. There was no change in cytoplasmic p65 expression in response to FL whereas nuclear p65 protein levels increased. FL treatment of DU145 cells resulted in decreased c‐fos protein levels and increased c‐jun protein levels. No change in IκBα occurred in response to FL however FL increased the expression of p‐IκBα protein levels. These results suggest that cranberry FL has the ability to inhibit the expression of MMP‐2/‐9 activity in DU145 cells at a concentration which is not substantially cytotoxic to these cells suggesting that FL inhibits MMPs in a targeted manner. The FL‐mediated effects involve a number of cell signaling pathways.[N.C.I.C.‐Canadian Cancer Society, P.E.I. Health Research Program, The Cranberry Institute (Wisconsin Cranberry Board) funded]
Investigation of the role of dietary flavonoids on cell death: evidence to support a non‐apoptotic mechanism
Authors: Lialiutska Tetiana , Ngo Nhi , White Brandon
Published: June 2021

Flavonoids are polyphenolic compounds widely distributed in plants and have been shown to be cytotoxic to cancer cells. Our lab has previously shown that some flavonoids are able to induce cytotoxicity in human breast cancer cell lines and also able to inhibit caspase activity. Our current study aims to identify the specific molecular pathways required for flavonoid induced cytotoxicity. MDA‐MB‐231 cells, mouse embryonic fibroblasts (MEFs) lacking caspase‐3 and caspase‐7, and primary baby mouse kidney epithelial cells lacking bax and bak were cultured per recommended protocols. Cells were treated with 100 μM flavonoid and cell counts, extracts and/or cytochrome c release were measured at 24, 48, and 72 hours after treatment. Flavonoid‐treated MDA‐MB‐231 cells showed cytochrome c release. We could not detect caspase‐3 or ‐7 cleavage in MDA‐MB‐231 cells at any time point measured. PARP cleavage occurred in MDA‐MB‐231 cells after 6 hours of flavonoid treatment. These results suggest that cytotoxicity in breast cancer cells may involve caspase‐independent mechanisms. To test this, we treated caspase‐deficient MEFs with various flavonoids compared to wild‐type controls and performed cell counts. Flavonoids induced cytotoxicity in caspase‐deficient MEFs similar to wild‐type controls. Finally, we have looked at flavonoid induced cytotoxicity in bax/bak deficient cells and do not see a difference in cytotoxicity compared to wild‐type controls. Taken together, our results suggest that flavonoids are inducing cytotoxicity through a non‐classical apoptotic mechanism which may require the release of cytochrome c but not caspases, bax, or bak.
Rubber plant (Hevea brasiliensis) extract inhibits polyisoprenylated methylated protein methyl esterase and cancer cell viability
Authors: Hester Ulyssa N , Amissah Felix , Aguilar Byron , Duverna Randolph , Lamango Nazarius
Published: June 2021

The polyisoprenylation pathway enzymes have been targeted for anticancer studies because aberrant polyisoprenylated protein activity is associated with ~30% of cancers. Polyisoprenylated methylated protein methyl esterase (PMPMEase) is a pivotal enzyme involved in the only reversible and possibly regulatory terminal reaction of the pathway. Inhibitors of PMPMEase have been shown to cause cell degeneration and so may be useful as anticancer agents. Hevea brasiliensis is a popular tropical commercial plant and a rich source of rubber, a polyterpene. We therefore propose that it may contain natural polyisoprenyl moieties which may inhibit PMPMEase. Enzyme assays revealed that methanolic extract of H. brasiliensis significantly inhibits PMPMEase activity. The most inhibitory fraction of extract also inhibited the viability of human breast cancer MDA‐MB‐231 and prostate cancer Lncap cells after 72 h exposure with EC50 values of 13 and 15 ìg/mL, respectively. Analysis with ethidium bromide/acridine orange suggests apoptosis as the mode of cell death. PMPMEase assays in MDA‐MB‐231 and Lncap cells also showed decreased enzyme activity after 24 h exposure. Consistent with previous studies using PMPMEase inhibitors, the apoptotic effects of the H. brasiliensis extract are most likely due to PMPMEase inhibition. Thus some of the isoprene compounds in the plant may be useful in anti‐cancer therapy.
Alterations in the Activity of the Yeast Peroxiredoxin Tsa1 Upon Modification by Alkylating Agents
Authors: Brown Haley Ann , Justice Samantha L , Garcia Francisco J , Carroll Kate S , Morano Kevin A , West James D
Published: June 2021

Organisms have evolved a variety of defense mechanisms to deal with adverse environmental challenges, including exposure to reactive oxidants and organic electrophiles. In Saccharomyces cerevisiae, one of the proteins involved in defense against oxidants is the peroxiredoxin thioredoxin peroxidase 1 (Tsa1). Tsa1 possesses two highly reactive active site cysteine residues that undergo oxidation to form a disulfide bond during catalysis. Here, we report that Tsa1 is a cellular target of electrophilic alkylating agents. In cells treated with the electrophilic protein cross‐linkers diethyl acetylenedicarboxylate and divinyl sulfone, Tsa1 is cross‐linked to itself and other proteins, including cytosolic thioredoxins. Cross‐linking of Tsa1 is dependent on its active site cysteine residues, implying that these residues are subject to electrophilic modification. We tested whether pre‐treatment of Tsa1 with the alkylating agent N‐ethylmaleimide inhibited its peroxidase activity and found that alkylation of the protein prevents its oxidation by H2O2. Despite this, yeast strains lacking tsa1 are hypersensitive to cell death induced by electrophiles and have an increased amount of proteins accumulating in insoluble aggregates under similar conditions. Since Tsa1 also functions as a molecular chaperone, our results suggest that its molecular chaperone activity may account for its protection against electrophiles.
Disruption of the HIF‐1α/p300 interaction as a means of inhibiting angiogenesis
Authors: Reece Kelie M , Richardson Emily D , Pisle Stephen T , Holly Alesia J , Campbell Tessa J , Figg William D
Published: June 2021

Solid tumors develop regions of hypoxia because of an imbalance in oxygen supply and consumption. Thus, adaptation of cancer cells to hypoxia is critical for tumor survival. The most important mediator of the cell's response to reduced oxygen is the hypoxia inducible factor‐1 (HIF‐1) transcription factor. Due to the involvement of HIF in tumor progression and angiogenesis, inhibition of HIF‐mediated transcription has the potential for treatment of cancer. Since p300 is a crucial coactivator of hypoxia‐inducible transcription, disruption of the HIF‐1α/p300 complex is desirable as a selective mechanism of inhibiting HIF activity. Previous data have shown that several members of the epidithiodiketopiperazine (ETP) family of natural products, namely, chetomin, chaetocin, and gliotoxin, block the interaction between HIF‐1α and p300. We performed a series of rat aortic ring assays and found that ETP treatment had antiangiogenic effects, apparently through disruption of the HIF‐1α/p300 complex, as ETPs blocked co‐immunoprecipitation of HIF‐1α and p300. Aortic rings were immunostained for HIF‐1α to confirm its upregulation. These results show the potential of targeting this interaction in cancer therapeutics. We are currently using mouse xenografts to test the effects of these ETPs on tumor growth, and thus determine the feasibility of moving these compounds forward into pre‐clinical development.
HSP90 is a Novel Target of Thrombospondin‐1 to Regulate Colon Cancer Development
Authors: Ling Jun , Gutierrez Linda , Lopez-Dee Zenaida , Pan Songqin , Kalter Valarie , Cottell Colby , Nye Derek
Published: June 2021

Thrombospondin‐1 (TSP‐1) is the first identified endogenous inhibitor of angiogenesis; it has been demonstrated to regulate colon cancer development in a colitis‐associated mouse model. Here, we reported for the first time that TSP‐1 down‐regulated the expression of HSP90α. TSP‐1 knock‐out mice (TSP‐1−/−) showed no difference at HSP90α level with wild type (WT) mice under normal and mild inflamed conditions, but expressed elevated HSP90α at inflamed stage induced by DSS/AOM and a complicated pattern of HSP90α degradation at cancerous lesion stage. The over‐expression of HSP90α in TSP‐1−/− mice under these conditions was confirmed by mass spectrometry, real‐time RT‐PCR and immunohistochemical staining. The transient overexpression of TSP‐1 in HEK 293 cells down‐regulated the level of HSP90α, confirming the casual relationship of TSP‐1 with HSP90α. To search for kinases downstream TSP‐1 signaling, Erk2 was identified to be sensitive to TSP‐1 activation, thereby inhibition of Erk2 activity by kinase inhibitor enhanced the level of HSP90α, defining Erk2 as one of effector kinases to regulate the expression or stability HSP90α by TSP‐1. Co‐immunoprecipitation revealed that HSP90α interacted with TSP‐1, thus providing another mechanism that TSP‐1 might regulate HSP90α at protein‐protein interaction level. In sum, we identified a novel mechanism of TSP‐1 function via HSP90α in colon cancer progression.
Structure and function of E3 ubiquitin ligase mindbomb RING domain
Authors: Wardlow Robert D , Choi Sung Hee , McMillan Brian , Blacklow Stephen C
Published: June 2021

Aberrant Notch receptor signaling is implicated in many different forms of cancer, highlighting the importance of tight regulation in normal signal transduction. Productive signaling in vivo relies on endocytosis of Notch DSL‐family ligands, which are marked for uptake by ubiquitination on their cytoplasmic tails. Mindbomb 1 (MIB1) is an important E3 ubiquitin (Ub) ligase for these ligands in mammals, but the mechanism by which it catalyzes Ub transfer onto the ligand tails is poorly understood. The purpose of this study was to characterize the triple RING domain of MIB1, which is required for delivery of ubiquitin to the ligand tails. Preliminary studies have revealed that Ub is covalently loaded onto the RING domains of MIB1. The bound Ub is released by the addition of a reducing agent, suggesting that the site of attachment is at a cysteine residue. Subsequent studies will focus on determining the site of attachment and on the preparation of complexes between the RING domain and an E2 ligase with a view toward future biochemical and X‐ray crystallographic studies. Together, these studies will provide substantial new insights into the action of MIB1 and a better understanding of the events that lead to Notch activation. This work was funded by NIH and foundation awards to SCB. This work was also funded, in part, by NIH/NIGMS MARC U*STAR T34 08663 NRSA to UMBC and the Harvard Medical School Division of Medical Sciences (RDW).
The effectiveness of images in the development of conceptual understanding in undergraduate biochemistry classes: What do we know?
Authors: Milner Rachel
Published: June 2021

Many students who are required to take biochemistry find it difficult to understand. One factor which may contribute to this is the abstract nature of the subject, which is understood almost entirely through representations, analogies, models, and maps. An enormous selection of images representing biochemical concepts is available on the internet, and in text books, yet we know very little about how, or whether, they work in communicating important concepts accurately. This presentation starts by exploring general aspects of visual literacy and then reviews the few investigations of student comprehension and interpretation of biochemical images reported in the literature. The contribution of images to difficulties in conceptual understanding is discussed, and a possible role for students’ cognitive differences is considered. It is argued that we need to know much more about how and whether the images we use in communicating biochemical concepts ‘work,’ and some implications for educational practice in biochemistry are raised.
Design of Purification and Analysis Protocols for Riboflavin Binding Protein in an Undergraduate Biochemistry Laboratory
Authors: Murray Tracey Arnold
Published: June 2021

One of the common protocols of undergraduate biochemistry laboratories is the purification of a protein of interest. A protocol to purify riboflavin binding protein (RBP) was modified from published and unpublished sources for use in the undergraduate Biochemistry Laboratory course at Capital University (Chemistry 452). RBP is an excellent choice for purification in the undergraduate laboratory. Because it can be isolated from chicken eggs, no large and time‐consuming bacterial cultures are necessary. The yellow color of RBP makes it easy to follow throughout the purification protocol and less likely the students will lose the protein during the course of the purification. The purification protocol also includes many basic purification techniques, including both ion‐exchange and size exclusion column chromatography and salt precipitation. Once the purification protocol is completed, the protein can be analyzed for purity using gel electrophoresis and the ratio of riboflavin to protein can be analyzed using UV‐Vis spectrophotometry. Because of the fluorescence properties of both riboflavin and the RBP apoprotein, the unfolding properties of RBP can be easily examined.
Using distance leaning tools as a mechanism to create a STEM mentoring opportunity
Authors: Ortiz Phillip , Duncan-Poitier Johanna , Groome Meghan , Hoffman Kiryn , Lansing Jill , Wortel Stephanie
Published: June 2021

There is no doubt that the United States needs a larger pool of STEM‐literate citizens. The New York Academy of Sciences (NYAS) has developed a program in which graduate students from New York City universities are trained to act as mentors for K12 students from under‐performing schools. This program served 2,100 students over the past year in the form of 25,000 hours of instruction. The graduate students receive ongoing face‐to‐face (F2F) training at NYAS in proper pedagogy and also the materials necessary for delivering workshops in topics such as genetics and robotics. To allow this program to expand to the entirety of New York State, NYAS and the State University of New York (SUNY) are forming a partnership in which SUNY graduate students will be trained and supported as mentors. To achieve this goal we are developing a series of courses that will be delivered via distance learning tools. These courses will allow the graduate students and their site supervisors to learn the same material and skills as those who attend F2F sessions, as well as create ‘learning communities of scholars’ in which the students can share their experiences and insights.
Teaching biochemistry and molecular biology using dihydrofolate reductase as an expression system
Authors: Lau Joann , Gilbert Michele
Published: June 2021

The enzyme dihydrofolate reductase (DHFR) converts dihydrofolic acid to tetrahydrofolic acid, thereby regulating the synthesis of purine and certain amino acids. Since DHFR plays such an important role in cell proliferation and growth, it was the first enzyme targeted for chemotherapy. The objective of this project is to teach molecular and biochemical techniques by having students induce gene expression, purify and enzymatically assay for DHFR activity. During this semester‐long project, students induce expression in recombinant bacteria and purify the DHFR protein using IMAC (immobilized metal affinity chromatography) resin. Students check purity via SDS‐PAGE electrophoresis and identify the fraction (insoluble vs. soluble) containing DHFR. Additionally, they design PCR primers for site‐directed mutagenesis, verify PCR success via restriction enzyme digestion and agarose gel electrophoresis, transform into expression competent cells, and confirm the amino acid mutation by DNA sequencing. Students then examine specific activity of the wildtype DHFR protein and compare it with the mutant DHFR protein. They also determine protein concentrations using the Bradford assay and perform Western blot analysis to detect glutathione S‐transferase (GST) and histidine (His) tags. All student groups successfully purified DHFR and detected both GST and His tags by Western blot analysis. Site‐directed mutagenesis showed a decrease in specific activity ranging from 32–122% compared to the wild‐type protein. This project provides students with the opportunity to gain hands‐on experience with a multitude of laboratory techniques as well as the opportunity to design and implement cutting edge research approaches.
A Novel Approach To Science ‐ Did Alice Learn Toxicology From The Mad Hatter?
Authors: Shende Vikram Vijay , Benore Marilee A
Published: June 2021

Stories and case studies are used to facilitate learning and understanding of conceptually difficult material. To this end, we investigated using well‐known children's literature to link past knowledge to new subject matter. Referencing a student's familiarity with one topic to teach a completely different topic may increase a student's ability to retain and understand material. To this end, lesson plans were created using The Mad Hatter, a key figure in The Adventures of Alice in Wonderland, for lessons on the physical properties, toxicology and biochemistry of mercury.
Dose response effect of almond consumption on serum fatty acid profile and coronary heart disease risk: a randomized controlled crossover trial
Authors: Kendall Cyril WC , Nishi Stephanie , Yoon Ana-Maria , Esfahani Amin , Lapsley Karen G , Jenkins David JA , Bazinet Richard P
Published: June 2021

Background

Consumption of almonds, has been associated with decreased risk of coronary heart disease (CHD), which may be related to their fatty acid (FA) composition.

Methods

27 hyperlipidemic subjects consumed three iso‐energetic (mean 423 kcal/d) supplements in 1‐month phases: 1. full‐dose almonds (50â€“100g/d); 2. half‐dose almonds with half‐dose muffins; and 3. full‐dose muffins. Fasting blood was obtained at weeks 0 and 4 of each treatment and FA concentrations analyzed by TLC and GC.

Results

On both the half‐ and full‐dose almond supplements, the % oleic acid (OA) and monounsaturated FA (MUFA) increased in the triacylglycerol (TG) fraction (OA: P=0.003, P<0.001; MUFA: P=0.004, P<0.001, respectively) and in the free fatty acid (FFA) fraction (OA: P=0.01, P=0.12; MUFA: P=0.04, P=0.06). In both the TG and FFA fractions, MUFAs were positively associated with HDL‐C (P=0.03, P=0.003), OA and MUFA were inversely associated with ten year risk of CHD (OA: P=0.059, P=0.03; MUFA: P=0.048, P=0.01), while saturated FA were inversely associated with HDL‐C (P<0.05) and positively associated with 10 year CHD risk (P<0.05).

Conclusion

Almond consumption increased the OA and MUFA content in the serum TG and FFA fractions, which were inversely associated with CHD lipid risk factors and overall 10 year CHD risk.

Supported by the Almond Board of California, Modesto, CA
Dietary n‐3 fish oil protects young mice against mortality during pneumonia
Authors: Fernandes Gabriel , Hinojosa Cecilia , Williams Paul , Orihuela Carlos
Published: June 2021

Background

Pneumonia is a common cause of infections in the elderly, particularly during winter seasons. In recent years, use of n‐3 fatty acids is rising, as a nutritional supplement in order to reduce serum triglyceride levels or to protect against cardiovascular disease. We formed a hypothesis that consumption of fish oil may reduce mortality in fish oil fed mice following a challenge with streptococcus pneumonia.

Methods

We fed 5% corn oil (AIN‐93 diet) or 4% fish oil/1% corn oil (AIN‐93 diet) to 2 month old female C57BL/6 mice. Fish oils included: regular fish oil 18/12, and 30/20, 55/5 or 5/60 (EPA/DHA) enriched diets. After 2 months on diets, mice were challenged intra‐nasally with a lethal dose of streptococcus (s) pneumonia serotype 4, strain TIGR4 (1.0 × 107 CFU). Survival was assessed over 10 days.

Results

Mice on 18/12, 30/20, 55/5 and 5/60 fish oil regimens had dramatically lower mortality than in n‐6 corn oil controls, 75% survival versus 12% survival in controls. Bacterial burden within the lungs 24 hours post infection revealed reduced levels in most of fish oil groups, except in 5/60 fed mice. All mice receiving dietary fish oil had >100‐fold less bacteria within the bloodstream than the controls.

Conclusion

This data supports our hypothesis that n‐3 fish oil protects against s. pneumonia mortality by decreasing bacteria burden in young mice, however it needs to be tested in older mice.
A Rural Community Engaged in a Cancer Prevention Program
Authors: Dawkins Norma L , Carter Vivian L , Howard Barbara
Published: June 2021

Bullock Count, Alabama is one of 17 Black Belt Counties characterized by rural socioeconomic decline, acute problem of poverty and poor health. It has one of the highest cancer rates in the state and the nation. Mortality rate for this county is 229.9 compared to the state (216.9) and the nation (188.6). The purpose was to assess health knowledge, status, and behaviors of participants engaged in a cancer prevention program.

Two instruments were designed 1) fact finding questionnaire and 2) a health behavior questionnaire which consisted of four sections: demographic information, health knowledge, health behaviors and health status. Both instruments revealed reliability of 0.80 and 0.83. Results indicated that 86% of respondents were female, 33% were college graduates, and 80 % earned an average annual income of $11,000 to $35,000. Participants (95%) were willing to take part in a community‐based cancer prevention program. Responses to health questions indicated that 71% associated moderate exercise and healthy diet with disease prevention, only 69 % believed that consuming five servings of vegetables a day can lower blood pressure. Approximately 50% rated their health as good while 71% indicated that their mental health was either fair or good. Community‐based intervention is paramount to the prevention of cancer and other chronic diseases. This research is supported by the U54 Cancer Research Partnerships
Prevalence of osteoarthritis and dietary pattern in older people above 60 in southern area of Korea
Authors: Shin Dongsoon , Oh Ha-Jung
Published: June 2021

This study was conducted by personal interview. The total number of subjects was 201(female 137, male 64), and all of them were above 60 years old. They lived in or around Changwon city and 51.7% of them resided in rural areas. The 38.8% of the subjects were suffered from joint disturbance of knee, leg or back pain. Compared to non‐symptomic group, the height and weight of symptomic group were lower(p<.05), but the body fat was higher(p<.05). Interestingly the educational status was lower in symptomic group than in non‐symptomic group(p<.001). Especially in women, the menopausal age of joint symptom group was earlier than that of non‐symptom group(p<.001). Meat, fish intake frequency were higher in joint symptomic group than in non‐symptomic group, in contrast seaweed and fruit intake were lower(p<.05). Therefore zinc and Vit C intake was significantly different according to osteoarthritic symptoms in older population(p<.05)

Grant Funding Source : Kyungnam University
Automated Extraction and Analysis of Salmonella enterica From Ground Turkey and Kitchen Surfaces
Authors: Williams Patrick E , Parrish Torrey , Duggan Megan , Chapman Jessica
Published: June 2021

Salmonella enterica is a gram negative bacterium commonly associated with raw poultry and food borne illness. Evogen has developed a fully Automated Sample Preparation (ASP) instrument which was used to extract and purify DNA from ground turkey meat cultures and kitchen surface swabs. DNA purified on the ASP was then amplified using loop‐mediated isothermal amplification (LAMP). Five gram samples of fresh ground turkey were placed in 50 mL of culture media in sterile culture flasks, inoculated with S. enterica at 3800 cfu/mL and placed in a 37°C incubator for 24 hours. Kitchen surfaces which had been in contact with the fresh turkey were inoculated at 3800 cfu/mL and allowed to dry for 30 minutes. Swabs were used to sample surfaces and placed in 1 mL of culture media and cultured at 37°C for 24 hours. Following incubation, a 200 μl aliquot from each sample was placed in an ASP cartridge for DNA extraction and purification. DNA concentration was measured after extraction. 5.0μl of extracted DNA was then used for LAMP. The LAMP reactions were held at 65ºC for 30 minutes and an annealing curve was performed at 98–75ºC. All culture and swab samples extracted on the ASP provided positive results via LAMP within 12 minutes. The mean concentration of DNA recovered from the samples was 21.0 ng/μl ± 2.8 ng/μl. This new sample preparation system provides high quality DNA that was rapidly detectable by LAMP.

Private Funding
Effect of hyperketonemia and L‐cysteine on monocyte adhesion to endothelial cells
Authors: Kanikarla-Marie Preeti , Jain Sushil K.
Published: June 2021

Frequent episodes of hyperketonemia are associated with higher incidences of vascular disease in type 1 diabetic patients. Previous studies demonstrate that hyperketonemia increases monocyte‐endothelial cell (EC) adhesion. L‐Cysteine is a semi‐essential amino acid with a free sulfhydryl group. Type 1 diabetic patients have lower blood levels of L‐cysteine. This study has examined the hypothesis that supplementation with L‐cysteine can decrease monocyte adhesion to endothelial cells and thereby delay or prevent vascular disease in type 1 diabetes. Human THP‐1 monocytes and Human umbilical venule endothelial cells (HUVECs) were cultured with acetoacetate (0–8 mM) for 24 hours. Monocyte adhesion to HUVECs was determined by using cell tracker green dye. Results show that there was an increase in monocyte adhesion to HUVEC monolayer¡¦s treated with 6 mM aetoacetate compared with control. Monocyte adhesion was blocked by almost 12% (p=0.04) when monocytes and HUVEC¡¦s were pre‐incubated with L‐cysteine (500 ƒÝM) for 4 hours before exposure to acetoacetate. This suggests that, L‐cysteine supplementation can lower monocyte adhesion to endothelium. Whether or not L‐cysteine inhibition of monocyte adhesion to ECs is mediated by down‐regulation of LFA‐1, CD‐14 and ICAM‐1 needs to be investigated. Supported by NIH and Office of Dietary Supplements (RO1 DK 072433) and Malcolm Feist Chair in Diabetes.
Adiponectin Enhances Fetal Fat Deposition
Authors: Qiao Liping , Yoo Hyung-sun , Madon Alysha , Kinney Brice , Lee Bonggi , Hay William W. , Shao Jianhua
Published: June 2021

Maternal obesity increases offspring birthweight and susceptibility to obesity. Adiponectin is an adipocyte‐secreted hormone with a prominent function in maintaining energy homeostasis. In contrast to adults, neonatal blood adiponectin levels are positively correlated with anthropometric parameters of adiposity. The main objective of this study is to investigate the role of adiponectin in maternal obesity‐enhanced fetal fat deposition. By using a high‐fat diet‐induced obese wild type mouse model, our study showed that maternal obesity increased fetal fat tissue mass with a significant elevation of fetal blood adiponectin. However, in adiponectin gene knockout mice, maternal high‐fat feeding failed to increase fetal fat tissue mass. Using chow‐fed lean dams and a cross breeding approach which genetically manipulated maternal and fetal adiponectin levels, our study further revealed that fetal adiponectin increased 1) fetal serum FFA and body fat mass, 2) liver triglyceride content and de novo lipogenic genes expression and 3) placental lipoprotein lipase levels. Together, our results indicate that adiponectin enhances fetal fat deposition and elevated fetal adiponectin mediates maternal obesity‐induced high birthweight. Our study also attributes adiponectin‐enhanced fetal fat deposition to increased placental fatty acid transport and fetal liver de novo lipogenesis.
Egg Consumption and Coronary Heart Disease among Diabetic Individuals: A Systematic Review of the Literature
Authors: Tran Nga L. , Barraj Leila M , Heilman Jacqueline
Published: June 2021

This study reviews epidemiological and experimental evidence on the relationship between egg consumption and coronary heart disease (CHD) risks among type II diabetes mellitus (T2DM) individuals and T2DM risk in non‐diabetic subjects. Four of the six studies that examined cardiovascular disease and mortality and egg consumption among diabetics found a statistically significant association. Of the seven studies evaluating incident T2DM and egg consumption, three prospective studies found a statistically significant association. Lack of adjustment for dietary confounders was a common study limitation. Differences in study design, T2DM status, exposure measurement, subject age, control for confounders and follow‐up time limit the feasibility of a meta‐analysis. A small number of experimental studies examined the relationship between egg intake and CHD risk biomarkers among diabetics or individuals with T2DM risk factors. Conflicting results coupled with small sample sizes prevent broad interpretation. Studies among healthy subjects found suggestive evidence that dietary interventions including eggs may reduce the risk of T2DM and metabolic syndrome. Given the study limitations, these findings need to be further investigated.
Protein and amino acid biofortification of staple crops has potential to reduce population risk of protein inadequacy in Sub‐Saharan Africa
Authors: Suri Devika , Strutt Nicholas , Ghosh Shibani
Published: June 2021

Introduction

Populations dependent on starchy staple crops are at risk of protein inadequacy. Biofortification can improve nutritional quality of food crops. This study examined potential of protein and amino acid biofortified staple crops to reduce risk of protein inadequacy in six Sub‐Saharan African and South Asian countries.

Methods

FAO food balance sheets and USDA nutrient data were used to determine mean per capita nutrient supply and estimate population risk of protein inadequacy (PRPI), adjusting for protein quality using the PDCAAS method. We modeled increases in protein/amino acids of six crops to improve total protein/protein quality. PRPI was calculated using 2005 food supply, with 60% substitution of domestically produced crop with biofortified crop.

Results

Biofortified crops reduced PRPI from: 77% to 54% in Mozambique (maize); 21% to 14% in Nigeria (sorghum); 18% to 12% in Uganda (plantain); 44% to 23% in Zambia (cassava). PRPI in Bangladesh (41%) and India (31%) did not improve with biofortified rice and wheat indicating deficit of total protein rather than poor protein quality at the food supply level.

Conclusion

Protein/amino acid biofortification of starchy staple crops has the potential to reduce PRPI in populations with low protein quality in their overall food supply. Further work will investigate effect of biofortified crops on protein inadequacy at an individual level.
Identification of N‐acetyltaurine as a novel metabolite of ethanol through metabolomics‐guided biochemical analysis
Authors: Shi Xiaolei , Yao Dan , Chen Chi
Published: June 2021

The influence of ethanol on small‐molecule metabolome and the role of CYP2E1 in ethanol‐induced hepatotoxicity were investigated using liquid chromatography‐mass spectrometry (LC‐MS) based metabolomics platform and Cyp2e1‐null mouse model. Histological and biochemical examinations of ethanol‐exposed mice indicated that the Cyp2e1‐null mice were more resistant to ethanol‐induced hepatic steatosis and transaminase activity than the wild‐type mice, suggesting CYP2E1 contributes to ethanol‐induced toxicity. Metabolomic analysis of urinary metabolites revealed time‐ and dose‐dependent changes in the chemical composition of urine. N‐acetyltaurine (NAT) was identified as a urinary metabolite that is highly responsive to ethanol exposure. Stable isotope labelling analysis determined that NAT, with its acetyl group originated from ethanol metabolites, is a novel metabolite of ethanol, and NAT biosynthesis during ethanol treatment is contributed by both endogenous metabolism and ethanol metabolism. In vitro incubation assays showed that both acetyl‐CoA and acetate can react with taurine to form NAT. However, the enzymatic reaction between taurine and acetate is much more relevant to the metabolite concentrations in vivo than the reaction between taurine and acetyl‐CoA, indicating the former reaction is the main route of NAT biosynthesis in vivo. Furthermore, the contribution of acetate to NAT biosynthesis was confirmed by the immediate presence and increase of deuterated NAT after feeding deuterated acetate. The incubations of tissues and cellular fractions with taurine and acetate indicated that the kidney has the highest NAT synthase activity among tested organs while the cytosol is the main site of NAT biosynthesis inside the cell. Overall, the combination of biochemical and metabolomic analysis revealed NAT is a novel metabolite of ethanol and a potential biomarker of hyperacetatemia.

Grant Funding Source: UMN startup fund for Chi Chen
Maintenance on an energy‐dense “cafeteria diet” reduces the reinforcing effectiveness of corn oil but not saccharin in rats
Authors: Freeman Kevin Bryan , Woolverton William L.
Published: June 2021

Rats made obese on energy‐dense diets show alterations in brain reward function that include decreased sensitivity to brain stimulation reward and decreased psychostimulant self‐administration. However, it is currently unclear how diet‐induced obesity affects the reinforcing effects of fat and sweet taste. The current study used behavioral economics (BE) and progressive‐ratio (PR) tests to determine if maintenance on a palatable, energy‐dense “cafeteria diet” (CD) alters fat and sweet taste reinforcement. In addition to ad lib chow, a CD consisting of high‐fat, high‐sugar snack foods was made available for 18‐h (extended access [EA]) or 1‐h (restricted access) per day throughout the experiment in two groups of rats. A third group received ad lib chow only (CO). After 40 days of CD treatment, the EA rats were approximately 100 g heavier than the other groups. The reinforcing effectiveness of corn oil and saccharin were then tested in a BE design and subsequently in a PR design. Both tests revealed that corn oil was a more effective reinforcer than saccharin in CO rats, and a more effective reinforcer in CO rats than in EA rats. There were no other differences within or between groups in either test. These results indicate that maintenance on a palatable, energy‐dense diet and/or obesity reduces the reinforcing effectiveness of a fat in the form of corn oil but does not affect the reinforcing effectiveness of sweet taste.
Increasing the number of masticatory cycles reduces appetite and modulates glycemic response and plasma gut hormone concentrations
Authors: ZHU YONG , HSU WALTER H , HOLLIS JAMES H
Published: June 2021

Eating slowly and chewing thoroughly are often recommended for weight management. However, few laboratory studies have been conducted to support this specific eating behavior as a means to control appetite. In a randomized cross‐over study, 21 healthy males consumed a fixed amount of pizza meal, by chewing each portion either 15 or 40 times before swallowing. Chewing rate was kept constant thus eating rate was slower in the 40 chews condition. Subjective appetite was measured by appetite questionnaires for three hours after meal, and plasma samples were collected for measurement of appetite‐related hormones and glucose. An ad libitum meal was served three hours later and the amount eaten measured. Compared with 15 chews condition, eating slowly by chewing 40 times per portion resulted in lower hunger (P=0.009), lower preoccupation with food (P=0.005) and lower desire to eat (P=0.002). Meanwhile, higher plasma level of glucose (P=0.024), insulin (P<0.001), gastric inhibitory polypeptide (P<0.001) and cholecystokinin (P=0.045) were observed with lower plasma level of ghrelin (P=0.051) following the 40 chews condition. However, the food intake at the subsequent meal did not differ. The results suggest eating slowly by increasing masticatory cycles could reduce postprandial appetite and may be a potential strategy for body weight management.

Grant Funding Source: Iowa State University
Effect of masticatory cycles on postprandial appetite and subsequent food intake in seniors
Authors: ZHU YONG , HSU WALTER H , HOLLIS JAMES H
Published: June 2021

Seniors are a population at the increased risk of inadequate food intake. It is not clear how appetite and postprandial metabolism are influenced in this age group by change in the number of masticatory cycles during ingestion. In a randomized cross‐over study, 15 senior males consumed a fixed amount pizza meal, by chewing each portion 15 or 40 times before swallowing. Appetite questionnaires and plasma samples were collected at regular intervals over three hours following meal consumption. An ad libitum meal was provided three hours later and the amount eaten measured. Compared to 15 chews, making 40 chews per portion resulted in lower hunger (P<0.001), lower preoccupation with food (P<0.001) and lower desire to eat (P<0.001). Higher levels of plasma glucose, insulin and gastric inhibitory polypeptide were found immediately following the 40 chews (P<0.05), but they became significantly lower later (P<0.05). No effect on cholecystokinin and ghrelin was found. There was a trend toward significant reduction in food intake at the subsequent meal following the 15 chews condition (P=0.066). The results suggest that increasing the number of chews promotes postprandial satiety in senior males but also paradoxically promotes food intake at the subsequent meal. The impaired control of food intake in seniors and different glycemic responses under different chewing conditions may partly explain for the results.

Grant Funding Source: Iowa State University
High resolution carotenoid separations of serum and natural products using UHPLC
Authors: Craft Neal E.
Published: June 2021

Carotenoids have been measured using HPLC with pressures up to 6000 psi for nearly 35 years. Recently, UHPLC, offering pressures up to 18,000 psi, has become readily available. These high pressures permit the use of <2um particle packings to produce very high efficiencies and rapid separations. Alternatively, UHPLC can be used to produce much higher resolution separations of carotenoids. Currently few sub‐2um column packings are available.

Objective

To compare several commercial columns and mobile phase combinations to determine the separation efficiency and selectivity using UHPLC and establish high resolution separations.

Results

A good HPLC separation with a 3um column produces about 20,000 theoretical plates. Multiple UHPLC columns were used in series to achieve unique selectivity and nearly 50,000 plates. The data from carotenoid standards was used to predict elution of other carotenoids and choose conditions for high resolution separations. Selected conditions were used to separate carotenoids in serum and natural products.

Conclusions

UHPLC was successfully used in high‐resolution mode to achieve separations previously unattainable with conventional HPLC.
Effects of lecithin/oil ratio in salad dressing on the bioavailability of fat soluble micronutrients in salad vegetables
Authors: Zhang Yinghui , Zhou Yang , Flendrig Leonard , Gribnau Michiel , White Wendy S.
Published: June 2021

The objectives were to determine the effects of the lecithin/oil ratio in salad dressing on: 1) the absorption of carotenoids, phylloquinone and tocopherols in salad vegetables; 2) the absorption of retinyl palmitate formed from the ingested α‐ and β‐carotene. Twelve healthy women each consumed 3 identical salads with 3 different salad dressings which each contained 4 g of phylloquinone‐ and tocopherol‐stripped soybean oil. The soybean oil contained (by wt) 0%, 1% or 4% added soybean lecithin. The order in which the salads were consumed was randomly assigned; salads were separated by ≥ 2 week. Blood samples were collected at baseline and 2, 3.5, 5, 7, and 9.5 h postprandially. Chylomicron and large very low density lipoprotein (VLDLA) fractions were analyzed by HPLC with coulometric array electrochemical detection. In each lipoprotein fraction, there were no differences among salad dressings in the area under the curves (AUCs) for the fat‐soluble micronutrients. The exception was a decrease in the AUC for phylloquinone in the chylomicron fraction when the salad dressing oil containing 4% lecithin was compared with that containing 0% lecithin (P < 0.02). In conclusion, the added lecithin in the oil in the salad dressing did not affect the intestinal absorption of fat soluble micronutrients with the exception of vitamin K1. Supported by Unilever R&D.
Ferroportin1 in hepatocytes and macrophages mediates systemic iron homeostasis
Authors: Zhang Zhuzhen , Zhang Fan , Guo Xin , An Peng , Tao Yunlong , Wang Fudi
Published: June 2021

The liver is a major site for iron storage, but hepatocyte iron efflux mechanisms are unclear. To examine the hypothesis that Ferroportin1 (Fpn1) is a critical iron exporter in hepatocytes and macrophages, we generated both hepatocyte‐specific Fpn1 deletion mice (Fpn1Alb/Alb), and mice that lacked Fpn1 in hepatocytes and macrophages (Fpn1Alb/Alb;LysM/LysM). When fed a standard diet, Fpn1Alb/Albmice showed mild hepatocyte iron retention. However, RBC and hemoglobin levels were normal, indicating intact erythropoiesis. When fed an iron‐deficient diet, Fpn1Alb/Albmice showed impaired liver iron mobilization and anemia, with much lower RBC and hemoglobin, indicating that erythropoiesis depended upon both iron storage and iron demand status. Thus Fpn1 is critical for hepatocyte iron release. On standard diet, Fpn1Alb/Alb;LysM/LysM mice displayed substantially increased iron retention with intact erythropoiesis implying compensatory intestinal iron absorption. When fed an iron‐deficient diet, as iron mobilization from hepatocytes and iron recycling from macrophages were impaired, Fpn1Alb/Alb;LysM/LysM mice showed severe iron‐deficiency anemia regardless of their iron store status. Our data reveal new insights into the relationship among Fpn1‐mediated iron mobilization, iron storage, and iron absorption as these factors interact to maintain systemic iron homeostasis.

Grant Funding Source: MOST of China (#2009CB941400, 2011CB966200); NSFC of China (# 10979071, 30970665, 31030039)
Copper transporter 1 (CTR1) and the mechanisms of Cu uptake from blood plasma proteins by mammalian cells
Authors: Farhad Ramin , Kidane Theodros Z , Lee Kyoung Jin , Santos Abraham , Linder Maria C
Published: June 2021

CTR1 is the only specific Cu uptake transporter so far identified in mammalian cells. However in some cell types, Ag(I) (which inhibits CTR1) does not impede Cu uptake from plasma proteins or the histidine complex. To further test the importance of CTR1, we measured rates of uptake in cells with/without knockdown and knockout. siRNA knockdown (65–85%) of CTR1 mRNA made no difference to rates of Cu(II) uptake from human albumin and alpha2macroglobulin by human mammary epithelial and hepatic cell lines. Uptake of Cu from Cu(I)‐histidine or Cu(II)‐mouse albumin by mouse embryonic fibroblasts was only ~15% less in Ctr1‐null versus wild type cells (kindly provided by Dennis Thiele). Maximum rates of uptake from the his complex were ~10× greater for Cu(I) than Cu(II). The kinetics of Cu(II) uptake from mouse albumin were closer to those of Cu(I)‐his (Vmax 14 pmol/min/mg cell protein; Km 1 uM), while those from human albumin were similar to Cu(II)‐his (Vmax 4–6, Km 2–4.5). Cell surface Cu(II) and Fe(III) reductase activity was detected; but Fe(III) failed to inhibit uptake from Cu(II)‐albumin. In the Ctr1 null cells, there also was some inhibition by Ag(I). It is concluded that mammalian cells contain at least one additional Ag(I)‐inhibitable Cu transporter, that prefers Cu(I), probably receiving it upon reduction of Cu(II) by a cell surface reductase. Supported by HHMI and USPHS Grant RO1 HD46949.
The inhibitory effect of dietary fructose on lactation‐induced increases in rat epithelial calcium transport is mediated by fructose‐induced reductions in vitamin D levels
Authors: Douard Veronique , Suzuki Takuji , Sabbagh Yves , Lee Jackie , Shapses Sue , Lin Sheldon , Ferraris Ronaldo P
Published: June 2021

Pregnancy and lactation require marked increases in consumption and transport of dietary Ca2+ to maintain Ca2+ homeostasis and bone health. This increase in epithelial Ca2+ transport is regulated by increasing levels of calcitriol whose genomic effects are mediated by the vitamin D receptor (VDR). We recently showed that fructose (F) consumption reduced intestinal Ca2+ transport. We used lactating rats as animal model to test whether the deleterious effects of excessive F intake on Ca2+ transport is regulated by calcitriol and lead to bone defects. Pregnant and virgin (control) rats were fed isocaloric 63% F or, as controls, glucose and starch diets from d 2 of gestation to end of lactation. Compared to virgins, lactating dams fed glucose or starch had higher rates of intestinal Ca2+ transport, elevated intestinal and renal expression of Ca2+ transporters, as well as increased levels of calcitriol and 1‐alpha‐hydroxylase. F consumption prevented these lactation‐induced increases, and reduced VDR binding to promoter regions of TRPV6 and CaBP9k. Bone mineral density, content and mechanical strength each decreased with lactation, and this decrease was exacerbated by F diet. In lactating rats with enhanced Ca2+ needs, excessive F intake prevents, through a calcitriol‐dependent pathway, adaptive increases in epithelial Ca2+ transport, likely compromising bone quality (NSF IOS‐1121049, Benjamin Delessert)
Bone mineral density and vitamin D status in older women with and without metabolic syndrome
Authors: Lasley Kate , Changwatpol Pitipa , Hermann Janice R. , Bogale Alemtsehay , Stoecker Barbara J
Published: June 2021

This study investigated associations between serum 25‐ hydroxyvitamin D [25(OH)D] and bone mineral density (BMD) in women >50 years of age with and without metabolic syndrome (MetS). MetS as defined by the International Diabetes Foundation was waist >88 cm with two additional factors from elevated blood pressure, serum triglycerides or glucose or decreased HDL‐cholesterol. Forty women, half with metabolic syndrome (MetS), had whole body, lumbar spine, hip and forearm BMD assessed by dual‐energy X‐ray absorptiometry (DEXA) scan. Serum 25(OH)D concentrations were assessed by enzyme‐linked immunosorbent assay (Immunodiagnostics Systems Ltd., Fountain Hills, AZ). No women had 25(OH)D <25 nmol/L, 15% were between 25 ‐ <50, 55% were between 50‐<75, and 30% had ≥ 75 nmol/L. Mean (SD) for 25(OH)D was 62 (18) for women with MetS and was not significantly different (p<0.10) from the mean of 71 (15) for control women. Z scores for BMD for age were higher in the lumbar spine (p<0.0004) and hip regions (p<.0024) for women in the MetS group and BMD tended to be higher (p<0.06) in the whole body in the MetS group. BMD was not significantly different in the forearm between control and MetS groups. Overall, serum 25(OH)D did not correlate significantly with BMD in the sites measured. (Supported by Wentz Foundation and Oklahoma Agricultural Experiment Station, W2002)