Patients suffering major trauma and critical illness develop an injury-associated persistent anemia which is not related to acute blood loss. Understanding the pathophysiology of this persistent anemia would avoid the use of blood transfusions which is currently the only available treatment. Our overall goal is to develop treatment strategies for this persistent anemia. Injury and hemorrhagic shock worsen bone marrow (BM) dysfunction and inhibit the differentiation of hematopoietic progenitor cells (HPC) and lead to increased mobilization of HPC from the BM to the peripheral blood and sites of injury. Our recent studies suggest that this BM dysfunction is linked to a hyperadrenergic state and that with critical illness this hyperadrenergic state is prolonged. This proposal will test the central hypothesis that chronic adrenergic stimulation following injury and hemorrhagic shock worsens BM dysfunction further inhibiting the differentiation of HPCs and exaggerating the mobilization of HPCs from BM contributing to injury-associated persistent anemia.
Our specific aims are to:
Aim 1. Determine the effects of a persistent inflammatory milieu on BM erythroid differentiation and anemia.
Aim 2. Determine if excessive and ongoing HPC mobilization contributes to persistent anemia.
These aims will be examined in our established model of lung contusion and hemorrhagic shock followed by daily restraint to simulated chronic stress. To compliment both these aims we will also examine the use of beta adrenergic blockade and 6-hydroxydopamine to decrease the hyperadrenergic state and prevent BM dysfunction and thus alleviate persistent anemia.

Public Health Relevance

This research will study the deleterious effects of chronic stress following acute injury which is hypothesized to exacerbate injury-associated persistent anemia. In addition, this research will examine the potential therapeutic benefit of beta blockade in reducing stress hormones thereby decreasing the incidence of injury-associated persistent anemia and the need for blood transfusion. There are currently no alternative treatments for anemia except blood transfusions and a reduction in the number of blood transfusions can decrease costs, the number of infections, and death.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM105893-05
Application #
9112002
Study Section
Surgery, Anesthesiology and Trauma Study Section (SAT)
Program Officer
Somers, Scott D
Project Start
2013-09-24
Project End
2018-07-31
Budget Start
2016-08-01
Budget End
2017-07-31
Support Year
5
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Florida
Department
Surgery
Type
Schools of Medicine
DUNS #
969663814
City
Gainesville
State
FL
Country
United States
Zip Code
32611
Loftus, Tyler J; Mira, Juan C; Miller, Elizabeth S et al. (2018) The Postinjury Inflammatory State and the Bone Marrow Response to Anemia. Am J Respir Crit Care Med 198:629-638
Loftus, Tyler J; Kannan, Kolenkode B; Carter, Christy S et al. (2018) Persistent injury-associated anemia and aging: Novel insights. J Trauma Acute Care Surg 84:490-496
Loftus, Tyler J; Dessaigne, Camille G; Croft, Chasen A et al. (2018) A protocol for non-operative management of uncomplicated appendicitis. J Trauma Acute Care Surg 84:358-364
Loftus, Tyler J; Morrow, Megan L; Lottenberg, Lawrence et al. (2018) Occult bowel injury after blunt abdominal trauma. Am J Surg :
Loftus, Tyler J; Efron, Philip A; Bala, Trina M et al. (2018) Hypertonic saline resuscitation after emergent laparotomy and temporary abdominal closure. J Trauma Acute Care Surg 84:350-357
Loftus, Tyler J; Rosenthal, Martin D; Croft, Chasen A et al. (2018) The effects of beta blockade and clonidine on persistent injury-associated anemia. J Surg Res 230:175-180
Horiguchi, Hiroyuki; Loftus, Tyler J; Hawkins, Russell B et al. (2018) Innate Immunity in the Persistent Inflammation, Immunosuppression, and Catabolism Syndrome and Its Implications for Therapy. Front Immunol 9:595
Loftus, Tyler J; Brakenridge, Scott C; Croft, Chasen A et al. (2018) Successful nonoperative management of uncomplicated appendicitis: predictors and outcomes. J Surg Res 222:212-218.e2
Mira, Juan C; Nacionales, Dina C; Loftus, Tyler J et al. (2018) Mouse Injury Model of Polytrauma and Shock. Methods Mol Biol 1717:1-15
Loftus, Tyler J; Brakenridge, Scott C; Murphy, Travis W et al. (2018) Anemia and blood transfusion in elderly trauma patients. J Surg Res 229:288-293

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