Biochemical Phenomena, Metabolism, and Nutrition Commons^™

Identification Of Hydroxyxanthones As Na/K-Atpase Ligands, Zhongbing Zhang, Zhichuan Li, Jiang Tian, Wei Jiang, Yin Wang, Xiaojin Zhang, Zhuorong Li, Qidong You, Joseph Shapiro, Shuyi Si, Zijian Xie

Zijian Xie

We have screened a chemical library and identified several novel structures of Na/K-ATPase inhibitors. One group of these inhibitors belongs to polyphenolic xanthone derivatives. Functional characterization reveals the following properties of this group of inhibitors. First, like ouabain, they are potent inhibitors of the purified Na/K-ATPase. Second, their effects on the Na/K-ATPase depend on the number and position of phenolic groups. Methylation of these phenolic groups reduces the inhibitory effect. Third, further characterization of the most potent xanthone derivative, MB7 (3,4,5,6-tetrahydroxyxanthone), reveals that it does not change either Na⁺ or ATP affinity of the enzyme. Finally, unlike that of …

Marinobufagenin Induces Increases In Procollagen Expression In A Process Involving Protein Kinase C And Fli-1: Implications For Uremic Cardiomyopathy, Jihad Elkareh, Sankaridrug Periyasamy, Amjad Shidyak, Sandeep Vetteth, Jeremy Schroeder, Vanamala Raju, Imad Hariri, Nasser El-Okdi, Shalini Gupta, Larisa Fedorova, Jiang Liu, Olga Fedorova, M. Kahaleh, Zijian Xie, Deepak Malhotra, Dennis Watson, Alexei Bagrov, Joseph Shapiro

Zijian Xie

The cardiotonic steroid marinobufagenin (MBG) has been implicated in the pathogenesis of experimental uremic cardiomyopathy, which is characterized by progressive cardiac fibrosis. We examined whether the transcription factor Friend leukemia integration-1 (Fli-1) might be involved in this process. Fli-1-knockdown mice demonstrated greater cardiac collagen-1 expression and fibrosis compared with wild-type mice; both developed increased cardiac collagen expression and fibrosis after 5/6 nephrectomy. There was a strong inverse relationship between the expressions of Fli-1 and procollagen in primary culture of rat cardiac and human dermal fibroblasts as well as a cell line derived from renal fibroblasts and MBG-induced decreases in nuclear …

Stem Cell Transplantation Increases Antioxidant Effects In Diabetic Mice, Ming Li, Luca Vanella, Yuming Zhang, Ming Shi, Takashi Takaki, Joseph I. Shapiro M.D., Susuma Ikehera

Joseph I Shapiro MD

Intra bone marrow-bone marrow transplantation (IBM- BMT) + thymus transplantation (TT) has been shown to reduce the incidence of graft versus host disease (GVHD) and restore donor-derived T cell function. In addition, an increase in insulin sensitivity occurred in db/db mice after IBM-BMT+TT treatment. Heme oxygenase (HO)-1 is a stress inducible enzyme which exert antioxidant, antiapoptotic, and immune-modulating properties. We examined whether IBM-BMT+TT could modulate the expression of HO-1 in the kidneys of db/db mice. Six-week-old db/db mice with blood glucose levels higher than 250 mg/dl were treated with IBM-BMT+TT. Six weeks later, the db/db mice showed decreased body weight, …

Ouabain Decreases Sarco(Endo)Plasmic Reticulum Calcium Atpase Activity In Rat Hearts By A Process Involving Protein Oxidation, David Kennedy, Sandeep Vetteth, Miaorong Xie, Sankaridrug Periyasamy, Jingwei Xie, Chi Han, Venkatesha Basrur, Krishna Mutgi, Vladimir Fedorov, Deepak Malhotra, Joseph Shapiro

Jingwei Xie

The effect of cardiac glycosides to increase cardiac inotropy by altering Ca2+ cycling is well known but still poorly understood. The studies described in this report focus on defining the effects of ouabain signaling on sarcoplasmic reticulum Ca2+-ATPase function. Rat cardiac myocytes treated with 50 μM ouabain demonstrated substantial increases in systolic and diastolic Ca2+ concentrations. The recovery time constant for the Ca2+ transient, τ, was significantly prolonged by ouabain. Exposure to 10 μM H2O2, which causes an increase in intracellular reactive oxygen species similar to that of 50 μM ouabain, caused a similar increase in τ. Concurrent exposure to …

Effects Of Cardiotonic Steroids On Dermal Collagen Synthesis And Wound Healing, Nasser El-Okdi, Sleiman Smaili, Vanamala Raju, Amjad Shidyak, Shalini Gupta, Larisa Fedorova, Jihad Elkareh, Sankaridrug Periyasamy, Anna Shapiro, M. Kahaleh, Deepak Malhotra, Jingwei Xie, Khew Chin, Joseph Shapiro

Jingwei Xie

We previously reported that cardiotonic steroids stimulate collagen synthesis by cardiac fibroblasts in a process that involves signaling through the Na-K-ATPase pathway (Elkareh et al. Hypertension 49: 215–224, 2007). In this study, we examined the effect of cardiotonic steroids on dermal fibroblasts collagen synthesis and on wound healing. Increased collagen expression by human dermal fibroblasts was noted in response to the cardiotonic steroid marinobufagenin in a dose- and time-dependent fashion. An eightfold increase in collagen synthesis was noted when cells were exposed to 10 nM marinobufagenin for 24 h (P < 0.01). Similar increases in proline incorporation were seen following treatment with digoxin, ouabain, and marinobufagenin (10 nM × 24 h, all results P < 0.01 vs. control). The coadministration of the Src inhibitor PP2 or N-acetylcysteine completely prevented collagen stimulation by marinobufagenin. …

Platelet-Activating Factor Receptor Affects Food Intake And Body Weight, Wei Li, Thomas M. Mcintyre

Biomedical Sciences

“Let’s Move!” is a comprehensive initiative, launched by the First Lady, Michelle Obama, dedicates to solving problems of obesity, which is growing in child. The life behaviors do affect obesity; however, the mechanistic insight in molecular level is still not clear. In this study, by continually monitoring mouse body weight under chow and high fat western diets as well as metabolic, physical activity and food intake behaviors assessed in a CLAMS Comprehensive Lab Animal Monitoring System, we demonstrated that the platelet-activating factor receptor (PTAFR) contributes to modification of life behaviors. PTAFR does not affect metabolism of ingested dietary fat and …

Palmitic Acid Activation Of Dendritic Cells: Implications For Type 2 Diabetes, Dequina Angelina Nicholas

Loma Linda University Electronic Theses, Dissertations & Projects

Infiltration of immune cells into visceral adipose tissue is observed in type 2 diabetes development. Monocytes are recruited to obese visceral adipose tissue in large numbers and retain the ability to differentiate into dendritic cells, important antigen presenting cells in the immune system. Differentiation of monocytes into dendritic cells likely accounts for the increased number of dendritic cells observed in the adipose tissue of type 2 diabetic patients. We have demonstrated this differentiation process is regulated in part by a major reduction of linker histone proteins. In adipose tissue, dendritic cells are exposed to high levels of saturated fatty acids. …

Characterization Of The Nicotine-Induced Endoplasmic Reticulum Stress Response In The Rat Placenta In Vivo And In Vitro, Michael Ka Chun Wong

Electronic Thesis and Dissertation Repository

Nicotine exposure during pregnancy leads to adverse health outcomes, including compromised placental development. Although the molecular mechanisms remain elusive, recent studies identified that endoplasmic reticulum (ER) stress may underlie poor placentation. Therefore, we were interested in investigating the effects of nicotine exposure on the ER stress response in the placenta. A well-established maternal nicotine exposure rat model and Rcho-1 trophoblast giant cell model were utilized to address the research questions. Maternal nicotine exposure in vivo led to elevated ER stress in association with impaired disulfide bond formation and hypoxia. Nicotine exposure in vitro further differentiated that ER stress may be …

Synthesis And Flammability Testing Of Epoxy Functionalized Phosphorous-Based Flame Retardants, Vladimir Benin, Xuemei Cui, Alexander Morgan, Karl Seiwert

Chemistry Faculty Publications

Several potential new phosphorus-containing flame retardant molecules were evaluated for heat release reduction potential by incorporation of the molecules into a polyurethane, generated from methylene diphenyl diisocyanate and 1,3-propane diol. The heat release reduction potential of these substances was evaluated using the pyrolysis combustion flow calorimeter (PCFC). The polyurethanes were prepared in the presence of the potential flame retardants via solvent mixing and copolymerization methods to qualitatively evaluate their potential reactivity into the polyurethane prior to heat release testing. The functionality of the flame retardants was epoxide based that would potentially react with the diol during polyurethane synthesis. Flammability testing …

The Adaptive Change Of Hla-Drb1 Allele Frequencies Caused By Natural Selection In A Mongolian Population That Migrated To The South Of China, Hao Sun, Zhaoqing Yang, Keqin Lin, Shuyuan Liu, Kai Huang, Xiuyun Wang, Jiayou Chu, Xinyu Huang

Faculty Publications

Pathogen-driven balancing selection determines the richness of human leukocyte antigen (HLA) alleles. Changes in the pathogen spectrum may cause corresponding changes in HLA loci. Approximately 700 years ago, a Mongolian population moved from the north of China to the Yunnan region in the south of China. The pathogen spectrum in the south of China differs from that in the north. In this study, changes in the HLA genes in the Yunnan Mongolian population, as well as the underlying mechanism, were investigated. A sequence-based typing method (SBT) was used to genotype HLA-DRB1 in 470 individuals from two Mongolian populations and another …

New Technologies For Glycomic Analysis: Toward A Systematic Understanding Of The Glycome, John Rakus, Lara Mahal

John F. Rakus

Carbohydrates are the most difficult class of biological molecules to study by high-throughput methods owing to the chemical similarities between the constituent monosaccharide building blocks, template-less biosynthesis, and the lack of clearly identifiable consensus sequences for the glycan modification of cohorts of glycoproteins. These molecules are crucial for a wide variety of cellular processes ranging from cell-cell communication to immunity, and they are altered in disease states such as cancer and inflammation. Thus, there has been a dedicated effort to develop glycan analysis into a high-throughput analytical field termed glycomics. Herein we highlight major advances in applying separation, mass spectrometry, …

Using Lectinmicroarrays To Identify Regulatory Mechanisms For Mammalian Glycosylation, John F. Rakus

John F. Rakus

Glycosylation involves the post-translational addition of carbohydrates to protein molecules and is an intricate and indispensable biochemical process. Study of this complicated network of interactions is hindered by the lack of a coding template analogous to the genetic code, and by the vast structural complexity inherent to carbohydrate polymers. We use lectins (non-enzymatic carbohydrate-binding proteins of non-immunological origin) as microarray probes to identify carbohydrate features expressed on cellular surfaces. Specifically, we utilized lectin microarray technology to investigate the differences in carbohydrates expressed by the cell lines of the Nation Cancer Institute’s NCI-60 panel. Our investigation identified tissue-specific expression differences in …

The Sox9 Upstream Region Prone To Chromosomal Aberrations Causing Campomelic Dysplasia Contains Multiple Cartilage Enhancers, Baojin Yao, Qiuqing Wang, Chia-Feng Liu, Pallavi Bhattaram, Wei Li, Timothy J. Mead, James F. Crish, Véronique Lefebvre

Biomedical Sciences

Two decades after the discovery that heterozygous mutations within and around SOX9 cause campomelic dysplasia, a generalized skeleton malformation syndrome, it is well established that SOX9 is a master transcription factor in chondrocytes. In contrast, the mechanisms whereby translocations in the –350/–50-kb region 5 of SOX9 cause severe disease and whereby SOX9 expression is specified in chondrocytes remain scarcely known. We here screen this upstream region and uncover multiple enhancers that activate Sox9-promoter transgenes in the SOX9 expression domain. Three of them are primarily active in chondrocytes. E250 (located at – 250 kb) confines its activity to condensed prechondrocytes, …

Inhibition Of Elongation Factor 1a-1 Activity And Hepatic Lipotoxicity, Alexandra Margaret Anne Hetherington

Electronic Thesis and Dissertation Repository

Elongation factor 1A-1 (eEF1A-1) was previously identified as a mediator of fatty acid-induced cell death (lipotoxicity) downstream of endoplasmic reticulum (ER) stress. Furthermore, inhibition of the peptide elongation activity of eEF1A-1 with the cyclic depsipeptide didemnin B (DB) diminishes ER stress and lipotoxicity in cultured hepatocytes. Since ER stress is involved in nonalcoholic fatty liver disease (NAFLD), it was hypothesized that administration of DB to obese mice with NAFLD would reduce hepatic lipotoxicity. Treatment with DB for one week improved several parameters associated with hepatic lipotoxicity and modestly decreased food intake without evidence of illness. Liver triglycerides and protein markers …

Molecular Mechanisms Linking Amino Acid (Leucine) Deprivation To Igfbp-1 Hyperphosphorylation In Fetal Growth Restriction, Niyati M. Malkani

Electronic Thesis and Dissertation Repository

In this study, we explore the molecular mechanisms linking amino acid (leucine) deprivation to IGFBP-1 hyperphosphorylation in vitro. During pregnancy, a maladaptive fetal response to in utero amino acid deprivation leads to Fetal Growth Restriction (FGR). FGR infants display elevated phosphorylated IGFBP-1, which is associated with decreased IGF-I bioavailability. Leucine deprivation inhibits mechanistic target of rapamycin (mTOR) signaling and stimulates the amino acid response (AAR). Using HepG2 cells, a model for fetal hepatocytes, we demonstrate that in leucine deprivation, the AAR modulates total and phosphorylated IGFBP-1 while mTOR mediates total IGFBP-1 secretion only. We also reveal that protein kinases …

Occupational Deprivation Or Occupational Adaptation Of Mexican Americans On Renal Dialysis, Shirley A. Wells

Occupational Therapy Faculty Publications and Presentations

The aim of this study was to explore the occupational changes and perceptions experienced by Mexican Americans with end-stage renal disease (ESRD) and their families living with dialysis. In-depth interviews were conducted with 17 Mexican Americans with ESRD and 17 family members. The participants with ESRD described altered or lost activity patterns, capacities and freedoms. With a heightened awareness of death, the family members made altered occupational choices, which were consistent with their cultural values. Changes in the physical body, adhering to the dialysis regimen and environmental restrictions created barriers to occupational participation. These findings suggest that living with dialysis …

Fructose Mediated Non-Alcoholic Fatty Liver Is Attenuated By Ho-1-Sirt1 Module In Murine Hepatocytes And Mice Fed A High Fructose Diet, Komal Sodhi, Nitin Puri, Gaia Favero, Sarah Stevens, Charles Meadows, Nader G. Abraham, Rita Rezzani, Hayden A. Ansinelli, Edward Lebovics, Joseph I. Shapiro

Biochemistry and Microbiology

Background

Oxidative stress underlies the etiopathogenesis of nonalcoholic fatty liver disease (NAFLD), obesity and cardiovascular disease (CVD). Heme Oxygenase-1 (HO-1) is a potent endogenous antioxidant gene that plays a key role in decreasing oxidative stress. Sirtuin1 (SIRT1) belongs to the family of NAD-dependent de-acyetylases and is modulated by cellular redox.

Hypothesis

We hypothesize that fructose-induced obesity creates an inflammatory and oxidative environment conducive to the development of NAFLD and metabolic syndrome. The aim of this study is to determine whether HO-1 acts through SIRT1 to form a functional module within hepatocytes to attenuate steatohepatitis, hepatic fibrosis and cardiovascular dysfunction.

Methods …

Transport Of Bovine Milk Exosomes In Human Endothelial Cell, Rio Jati Kusuma

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

MicroRNAs (miRNAs) can be synthesized endogenously and cause gene repression. Encapsulation of miRNAs in exosomes confers protection against degradation and a vehicle for shuttling between cells and tissues, and cellular uptake by endocytosis. Exosomes can be found in biological fluids and foods including milk. Evidence suggests that humans absorb cow’s milk exosomes and deliver the microRNA cargo to peripheral tissues, consistent with gene regulation by nucleic acids across species boundaries. There is strong evidence that milk exosomes may cross the mucosa without re-packaging in mice. Here, we tested the hypothesis that human vascular endothelial cells transport milk exosomes by endocytosis, …

Manipulation Of The Microbiome And Its Impact On Functional Recovery Following Ischemic Stroke, Michal Jandzinski

Honors Scholar Theses

Each year, nearly 800,000 individuals residing in the United States will have a stroke. Of these, about 130,000 cases will prove fatal while many of the survivors will be forced to live with disability for the remainder of their lives. Out of all strokes over 87% are ischemic strokes. The widespread incidence of this debilitating condition costs the United States an estimated $36.5 billion dollars every single year. Despite this, clinicians are armed with very little to combat the disease. Recent research developments have brought about the rise in awareness about the importance of the microbiome, the various gut flora …

First Steps Phase Iii Initiative: Improving Oral Health And Healthy Weight In Children Final Evaluation Report, Carolyn E. Gray Mph, Kimberley S. Fox Mpa

Population Health & Health Policy

This report summarizes evaluation findings from Phase III and assesses change in oral health and healthy weight screening rates, referrals and related office system procedures in participating practices. The report also highlights challenges encountered and lessons learned in implementing changes to office systems, in responding to state policy changes, and in collecting and tracking oral health and healthy weight measures at the practice-level to inform quality improvement.