Medicine and Health Sciences Commons^™

Autotaxin-Lpa Signaling Contributes To Obesity-Induced Insulin Resistance In Muscle And Impairs Mitochondrial Metabolism, Kenneth D'Souza, Carine Nzirorera, Andrew M. Cowie, Geena P. Varghese, Purvi Trivedi, Thomas O. Eichmann, Dipsikha Biswas, Mohamed Touaibia, Andrew J. Morris, Vassilis Aidinis, Daniel A. Kane, Thomas Pulinilkunnil, Petra C. Kienesberger

Internal Medicine Faculty Publications

Autotaxin (ATX) is an adipokine that generates the bioactive lipid, lysophosphatidic acid (LPA). ATX-LPA signaling has been implicated in diet-induced obesity and systemic insulin resistance. However, it remains unclear whether the ATX-LPA pathway influences insulin function and energy metabolism in target tissues, particularly skeletal muscle, the major site of insulin-stimulated glucose disposal. The objective of this study was to test whether the ATX-LPA pathway impacts tissue insulin signaling and mitochondrial metabolism in skeletal muscle during obesity. Male mice with heterozygous ATX deficiency (ATX^+/−) were protected from obesity, systemic insulin resistance, and cardiomyocyte dysfunction following high-fat high-sucrose (HFHS) feeding. …

High-Density Lipoprotein Inhibits Serum Amyloid A-Mediated Reactive Oxygen Species Generation And Nlrp3 Inflammasome Activation, Preetha Shridas, Maria C. De Beer, Nancy R. Webb

Internal Medicine Faculty Publications

Serum amyloid A (SAA) is a high-density apolipoprotein whose plasma levels can increase more than 1000-fold during a severe acute-phase inflammatory response and are more modestly elevated in chronic inflammation. SAA is thought to play important roles in innate immunity, but its biological activities have not been completely delineated. We previously reported that SAA deficiency protects mice from developing abdominal aortic aneurysms (AAAs) induced by chronic angiotensin II (AngII) infusion. Here, we report that SAA is required for AngII-induced increases in interleukin-1β (IL-1β), a potent proinflammatory cytokine that is tightly controlled by the Nod-like receptor protein 3 (NLRP3) inflammasome and …

Synaptic Phospholipids As A New Target For Cortical Hyperexcitability And E/I Balance In Psychiatric Disorders, Carine Thalman, Guilherme Horta, Lianyong Qiao, Heiko Endle, Irmgard Tegeder, Hong Cheng, Gregor Laube, Torfi Sigurdsson, Maria Jelena Hauser, Stefan Tenzer, Ute Distler, Junken Aoki, Andrew J. Morris, Gerd Geisslinger, Jochen Röper, Sergei Kirischuk, Heiko J. Luhmann, Konstantin Radyushkin, Robert Nitsch, Johannes Vogt

Internal Medicine Faculty Publications

Lysophosphatidic acid (LPA) is a synaptic phospholipid, which regulates cortical excitation/inhibition (E/I) balance and controls sensory information processing in mice and man. Altered synaptic LPA signaling was shown to be associated with psychiatric disorders. Here, we show that the LPA-synthesizing enzyme autotaxin (ATX) is expressed in the astrocytic compartment of excitatory synapses and modulates glutamatergic transmission. In astrocytes, ATX is sorted toward fine astrocytic processes and transported to excitatory but not inhibitory synapses. This ATX sorting, as well as the enzymatic activity of astrocyte-derived ATX are dynamically regulated by neuronal activity via astrocytic glutamate receptors. Pharmacological and genetic ATX inhibition …

Capecitabine And Temozolomide In Neuroendocrine Tumor Of Unknown Primary, Aman Chauhan, Zainab Farooqui, Leaundra Murray, Heidi L. Weiss, Zin W. Myint, Arun Kumar A. Raajasekar, B. Mark Evers, Susanne M. Arnold, Lowell B. Anthony

Internal Medicine Faculty Publications

Incidence of low grade well-differentiated neuroendocrine tumors (NET) is on the rise. The North American Neuroendocrine Tumor Society estimates that the United States has more than 150,000 gastroenteropancreatic NET patients. About 10% of metastatic NETs can be unknown primary, and due to their rarity, dedicated treatment algorithms and regimens are not defined. Combination of capecitabine and temozolomide (CAPTEM) is one of the systemic treatments used in gastroenteropancreatic NETs. We explored clinical activity of CAPTEM in NET of unknown primary. Methods. Retrospective review of NET of unknown primary managed at the University of Kentucky over the past five years (2012–2016). …

Quality Of Life During Treatment With Chemohormonal Therapy: Analysis Of E3805 Chemohormonal Androgen Ablation Randomized Trial In Prostate Cancer, Alicia K. Morgans, Yu-Hui Chen, Christopher J. Sweeney, David F. Jarrard, Elizabeth R. Plimack, Benjamin A. Gartrell, Michael A. Carducci, Maha Hussain, Jorge A. Garcia, David Cella, Robert S. Dipaola, Linda J. Patrick-Miller

Internal Medicine Faculty Publications

Purpose

Chemohormonal therapy with docetaxel and androgen deprivation therapy (ADT+D) for metastatic hormone-sensitive prostate cancer improves overall survival as compared with androgen deprivation therapy (ADT) alone. We compared the quality of life (QOL) between patients with metastatic hormone-sensitive prostate cancer who were treated with ADT+D and those who were treated with ADT alone.

Methods

Men were randomly assigned to ADT+ D (six cycles) or to ADT alone. QOL was assessed by Functional Assessment of Cancer Therapy-Prostate (FACT-P), FACT-Taxane, Functional Assessment of Chronic Illness Therapy-Fatigue, and the Brief Pain Inventory at baseline and at 3, 6, 9, and 12 months. The …

Chemohormonal Therapy In Metastatic Hormone-Sensitive Prostate Cancer: Long-Term Survival Analysis Of The Randomized Phase Iii E3805 Chaarted Trial, Christos E. Kyriakopoulos, Yu-Hui Chen, Michael A. Carducci, Glenn Liu, David F. Jarrard, Noah M. Hahn, Daniel H. Shevrin, Robert Dreicer, Maha Hussain, Mario Eisenberger, Manish Kohli, Elizabeth R. Plimack, Nicholas J. Vogelzang, Joel Picus, Matthew M. Cooney, Jorge A. Garcia, Robert S. Dipaola, Christopher J. Sweeney

Internal Medicine Faculty Publications

Purpose

Docetaxel added to androgen-deprivation therapy (ADT) significantly increases the longevity of some patients with metastatic hormone-sensitive prostate cancer. Herein, we present the outcomes of the CHAARTED (Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer) trial with more mature follow-up and focus on tumor volume.

Patients and Methods

In this phase III study, 790 patients with metastatic hormone-sensitive prostate cancer were equally randomly assigned to receive either ADT in combination with docetaxel 75 mg/mm² for up to six cycles or ADT alone. The primary end point of the study was overall survival (OS). Additional …

Early Relapse After Autologous Hematopoietic Cell Transplantation Remains A Poor Prognostic Factor In Multiple Myeloma But Outcomes Have Improved Over Time, Shaji K. Kumar, Angela Dispenzieri, Raphael Fraser, Fei Mingwei, Gorgun Akpek, Robert Cornell, Mohamed Kharfan-Dabaja, Cesar Freytes, Shahrukh Hashmi, Gerhard C. Hildebrandt, Leona Holmberg, Robert Kyle, Hillard Lazarus, Cindy Lee, Jospeh Mikhael, Taiga Nishihori, Jason Tay, Saad Usmani, David Vesole, Ravi Vij, Baldeep Wirk, Amrita Krishnan, Cristina Gasparetto, Tomer Mark, Yago Nieto, Parameswaran Hari, Anita D'Souza

Internal Medicine Faculty Publications

Duration of initial disease response remains a strong prognostic factor in multiple myeloma (MM) particularly for upfront autologous hematopoietic cell transplant (AHCT) recipients. We hypothesized that new drug classes and combinations employed prior to AHCT as well as after post-AHCT relapse may have changed the natural history of MM in this population. We analyzed the Center for International Blood and Marrow Transplant Research database to track overall survival (OS) of MM patients receiving single AHCT within 12 months after diagnosis (N=3256) and relapsing early post-AHCT (< 24 months), and to identify factors predicting for early vs late relapses (24−48 months post-AHCT). Over three periods (2001–2004, 2005–2008, 2009–2013), patient characteristics were balanced except for lower proportion of Stage III, higher likelihood of one induction therapy with novel triplets and higher rates of planned post-AHCT maintenance over time. The proportion of patients relapsing early was stable over time at 35–38%. Factors reducing risk of early relapse included lower stage, chemosensitivity, transplant after 2008 and post-AHCT maintenance. Shorter post-relapse OS was associated with early relapse, IgA MM, Karnofsky < 90, stage III, > 1 line of induction and lack of maintenance. Post-AHCT early relapse remains …

Serum Amyloid A3 Is A High Density Lipoprotein-Associated Acute-Phase Protein, Lisa R. Tannock, Maria C. De Beer, Ailing Ji, Preetha Shridas, Victoria P. Noffsinger, Laura Den Hartigh, Alan Chait, Frederick C. De Beer, Nancy R. Webb

Internal Medicine Faculty Publications

Serum amyloid A (SAA) is a family of acute-phase reactants. Plasma levels of human SAA1/SAA2 (mouse SAA1.1/2.1) can increase ≥ 1,000-fold during an acute-phase response. Mice, but not humans, express a third relatively understudied SAA isoform, SAA3. We investigated whether mouse SAA3 is an HDL-associated acute-phase SAA. Quantitative RT-PCR with isoform-specific primers indicated that SAA3 and SAA1.1/2.1 are induced similarly in livers (∼2,500-fold vs. ∼6,000-fold, respectively) and fat (∼400-fold vs. ∼100-fold, respectively) of lipopolysaccharide (LPS)-injected mice. In situ hybridization demonstrated that all three SAAs are produced by hepatocytes. All three SAA isoforms were detected in plasma of LPS-injected mice, although …

Cardiac-Specific Inactivation Of Lpp3 In Mice Leads To Myocardial Dysfunction And Heart Failure, Mini Chandra, Diana Escalante-Alcalde, Shenuarin Bhuiyan, Anthony Wayne Orr, Christopher Kevil, Andrew J. Morris, Hyung Nam, Paari Dominic, Kevin J. Mccarthy, Sumitra Miriyala, Manikandan Panchatcharam

Internal Medicine Faculty Publications

Lipid Phosphate phosphatase 3 (LPP3), encoded by the Plpp3 gene, is an enzyme that dephosphorylates the bioactive lipid mediator lysophosphatidic acid (LPA). To study the role of LPP3 in the myocardium, we generated a cardiac specific Plpp3 deficient mouse strain. Although these mice were viable at birth in contrast to global Plpp3 knockout mice, they showed increased mortality ~ 8 months. LPP3 deficient mice had enlarged hearts with reduced left ventricular performance as seen by echocardiography. Cardiac specific Plpp3 deficient mice had longer ventricular effective refractory periods compared to their Plpp3 littermates. We observed that lack of Lpp3 enhanced cardiomyocyte …

Prevention Of Renal Apob Retention Is Protective Against Diabetic Nephropathy: Role Of Tgf-Β Inhibition, Patricia G. Wilson, Joel C. Thompson, Meghan S. Yoder, Richard Charnigo, Lisa R. Tannock

Internal Medicine Faculty Publications

Animal studies demonstrate that hyperlipidemia and renal lipid accumulation contribute to the pathogenesis of diabetic nephropathy (DN). We previously demonstrated that renal lipoproteins colocalize with biglycan, a renal proteoglycan. The purpose of this study was to determine whether prevention of renal lipid (apoB) accumulation attenuates DN. Biglycan-deficient and biglycan wild-type Ldlr^−/− mice were made diabetic via streptozotocin and fed a high cholesterol diet. As biglycan deficiency is associated with elevated transforming growth factor-β (TGF-β), in some experiments mice were injected with either the TGF-β-neutralizing antibody, 1D11, or with 13C4, an irrelevant control antibody. Biglycan deficiency had no significant effect …

Impact Of Individual Acute Phase Serum Amyloid A Isoforms On Hdl Metabolism In Mice, Myung-Hee Kim, Maria C. De Beer, Joanne M. Wroblewski, Richard J. Charnigo, Ailing Ji, Nancy R. Webb, Frederick C. De Beer, Deneys R. Van Der Westhuyzen

Internal Medicine Faculty Publications

The acute phase (AP) reactant serum amyloid A (SAA), an HDL apolipoprotein, exhibits pro-inflammatory activities, but its physiological function(s) are poorly understood. Functional differences between SAA1.1 and SAA2.1, the two major SAA isoforms, are unclear. Mice deficient in either isoform were used to investigate plasma isoform effects on HDL structure, composition, and apolipoprotein catabolism. Lack of either isoform did not affect the size of HDL, normally enlarged in the AP, and did not significantly change HDL composition. Plasma clearance rates of HDL apolipoproteins were determined using native HDL particles. The fractional clearance rates (FCRs) of apoA-I, apoA-II, and SAA were …