Local anesthetics worsen renal function after ischemia-reperfusion injury in rats

. Local anesthetics worsen renal function after ischemia-reperfusion injury in rats. Am J Physiol Renal Physiol 286: F111-F119, 2004. First published September 30, 2003 10.1152 10. /ajprenal.00108.2003ics are widely used during the perioperative period, even in patients with preexisting renal disease. However, local anesthestics have been shown to cause cell death in multiple cell lines, including human kidney proximal tubule cells. We questioned whether local anesthetics potentiate renal dysfunction after ischemia-reperfusion (I/R) injury in vivo. Rats were implanted with subcutaneous miniosmotic pumps that continuously delivered lidocaine (2 mg⅐kg Ϫ1 ⅐h Ϫ1 ), bupivacaine (0.4 mg⅐kg Ϫ1 ⅐h Ϫ1 ), tetracaine (1 mg⅐kg Ϫ1 ⅐h Ϫ1 ), or saline vehicle, and 6 h later the rats were subjected to 30 min of renal ischemia or to sham operation. Renal function was assessed by measurement of plasma creatinine at 24 and 48 h after renal I/R injury in the presence or absence of chronic infusions of local anesthetics and correlated to histological changes indicative of necrosis. The degree of renal apoptosis was assessed by three methods: 1) DNA fragmentation detected by terminal deoxynucleotidyl transferase biotin-dUTP nickend labeling staining, 2) DNA laddering detected after agarose gel electrophoresis, and 3) morphological identification of apoptotic tubules at the corticomedullary junction. We also measured the expression of the proinflammatory markers ICAM-1 and TNF-␣. Continuous local anesthetic infusion with renal I/R injury resulted in an increased magnitude and duration of renal dysfunction compared with the saline-infused I/R group. Additionally, both apoptotic and necrotic renal cell death as well as inflammatory changes were significantly potentiated in local anesthetic-treated rat kidneys. Local anesthetic infusion alone without I/R injury had no effect on renal function. We conclude that local anesthetics potentiated renal injury after I/R by increasing necrosis, apoptosis, and inflammation. acute renal failure; apoptosis; bupivacaine; inflammation; lidocaine; necrosis; tetracaine ACUTE RENAL FAILURE (ARF) secondary to ischemia-reperfusion (I/R) injury continues to be a significant clinical problem Patients with impaired preoperative renal function undergoing aortovascular surgery are at greatest risk for developing perioperative ARF (26). Local anesthetics are widely used in clinical practice, even in patients with impaired preoperative renal function. Epidural infusions of local anesthetic are routinely used for intraoperative and postoperative analgesia (frequently lasting several days) in patients undergoing major abdominal and vascular procedures. During induction of general anesthesia for endotracheal intubation, intravenous lidocaine is given routinely to blunt the sympathetic reflex to direct laryngoscopy. Local anesthetics are used to provide surgical anesthesia and analgesia in peripheral and central nervous system nerve blocks (spinal and epidural anesthesia). In the intensive care unit, lidocaine is frequently used as an antiarrythmic agent. Several in vitro studies found that local anesthetics increase cell death via apoptosis in neuronal, lymphocytic, and osteoblastic cell lines MATERIALS AND METHODS Implantation of Miniosmotic Pumps and Renal I/R Injury All protocols were approved by the Institutional Animal Care and Use Committee of Columbia University. Adult male Sprague-Dawley rats (225-275 g, Harlan Sprague-Dawley, Indianapolis, IN) were used. They had free access to rodent chow and water. Rats were anesthetized with intraperitoneal (ip) pentobarbital sodium (50 mg/kg or to effect) and implanted with subcutaneous miniosmotic pumps (model 2ML1, Alzet) that continuously delivered 10 l/h of 5% lidocaine (2 mg⅐kg Ϫ1 ⅐h Ϫ1 ), 1% bupivacaine (0.4 mg⅐kg Ϫ1 ⅐h Ϫ1 ), 2.5% tetracaine (1 mg⅐kg Ϫ1 ⅐h Ϫ1 ), or saline vehicle. The doses of local anesthetics delivered mimicked clinically administered doses for continuous epidural infusion for a 70-kg person during and after abdominal and vascular surgical procedures. Some rats were infused with 0.5% bupivacaine instead of 1% bupivacaine. Six hours later (the time required for osmotic pump priming), rats were reanesthetized with pentobarbital sodium. After 500 U of heparin were given ip, rats were placed on an electric heating pad under a warming light. Body temperature was monitored with a rectal probe and maintained at 37°C. They were allowed to spontaneously breath room air. After a laparotomy, rats were subjected to 30-min left renal ischemia after right nephrectomy. The duration of ischemia was shown in pilot studies to produce reversible and moderate renal dysfunction in rats. Some rats were subjected to only sham operation (anesthesia, laparotomy, and right nephrectomy) and received vehicle (saline) infusion, and others received a sham operation plus local anestheti

Differential protective effects of volatile anesthetics against renal ischemia-reperfusion injury in vivo

Background: Volatile anesthetics protect against cardiac ischemia-reperfusion injury via adenosine triphosphate-dependent potassium channel activation. The authors questioned whether volatile anesthetics can also protect against renal ischemia-reperfusion injury and, if so, whether cellular adenosine triphosphate-dependent potassium channels, antiinflammatory effects of volatile anesthetics, or both are involved. Methods: Rats were anesthetized with equipotent doses of volatile anesthetics (desflurane, halothane, isoflurane, or sevoflurane) or injectable anesthetics (pentobarbital or ketamine) and subjected to 45 min of renal ischemia and 3 h of reperfusion during anesthesia. Results: Rats treated with volatile anesthetics had lower plasma creatinine and reduced renal necrosis 24 -72 h after injury compared with rats anesthetized with pentobarbital or ketamine. Twenty-four hours after injury, sevoflurane-, isoflurane-, or halothane-treated rats had creatinine (؎ SD) of 2.3 ؎ 0.7 mg/dl (n ‫؍‬ 12), 1.8 ؎ 0.5 mg/dl (n ‫؍‬ 6), and 2.4 ؎ 1.2 mg/dl (n ‫؍‬ 6), respectively, compared with rats treated with pentobarbital (5.8 ؎ 1.2 mg/dl, n ‫؍‬ 9) or ketamine (4.6 ؎ 1.2 mg/dl, n ‫؍‬ 8). Among the volatile anesthetics, desflurane demonstrated the least reduction in plasma creatinine after 24 h (4.1 ؎ 0.8 mg/dl, n ‫؍‬ 12). Renal cortices from volatile anesthetictreated rats demonstrated reduced expression of intercellular adhesion molecule 1 protein and messenger RNA as well as messenger RNAs encoding proinflammatory cytokines and chemokines. Volatile anesthetic treatment reduced renal cortex myeloperoxidase activity and reduced nuclear translocation of proinflammatory nuclear factor B. Adenosine triphosphatedependent potassium channels are not involved in sevofluranemediated renal protection because glibenclamide did not block renal protection (creatinine: 2.4 ؎ 0.4 mg/dl, n ‫؍‬ 3). Conclusion: Some volatile anesthetics confer profound protection against renal ischemia-reperfusion injury compared with pentobarbital or ketamine anesthesia by attenuating inflammation. These findings may have significant clinical implications for anesthesiologists regarding the choice of volatil

Preclinical Development of Oncolytic Immunovirotherapy for Treatment of HPVPOS Cancers

Immunotherapy for HPVPOS malignancies is attractive because well-defined, viral, non-self tumor antigens exist as targets. Several approaches to vaccinate therapeutically against HPV E6 and E7 antigens have been adopted, including viral platforms such as VSV. A major advantage of VSV expressing these antigens is that VSV also acts as an oncolytic virus, leading to direct tumor cell killing and induction of effective anti-E6 and anti-E7 T cell responses. We have also shown that addition of immune adjuvant genes, such as IFNβ, further enhances safety and/or efficacy of VSV-based oncolytic immunovirotherapies. However, multiple designs of the viral vector are possible—with respect to levels of immunogen expression and method of virus attenuation—and optimal designs have not previously been tested head-to-head. Here, we tested three different VSV engineered to express a non-oncogenic HPV16 E7/6 fusion protein for their immunotherapeutic and oncolytic properties. We assessed their profiles of efficacy and toxicity against HPVPOS and HPVNEG murine tumor models and determined the optimal route of administration. Our data show that VSV is an excellent platform for the oncolytic immunovirotherapy of tumors expressing HPV target antigens, combining a balance of efficacy and safety suitable for evaluation in a first-in-human clinical trial. Keywords: VSV immunovirotherapy, HPV positive cancer, preclinica

Antibody Fab‐Fc properties outperform titer in predictive models of SIV vaccine‐induced protection

Abstract Characterizing the antigen‐binding and innate immune‐recruiting properties of the humoral response offers the chance to obtain deeper insights into mechanisms of protection than revealed by measuring only overall antibody titer. Here, a high‐throughput, multiplexed Fab‐Fc Array was employed to profile rhesus macaques vaccinated with a gp120‐CD4 fusion protein in combination with different genetically encoded adjuvants, and subsequently subjected to multiple heterologous simian immunodeficiency virus (SIV) challenges. Systems analyses modeling protection and adjuvant differences using Fab‐Fc Array measurements revealed a set of correlates yielding strong and robust predictive performance, while models based on measurements of response magnitude alone exhibited significantly inferior performance. At the same time, rendering Fab‐Fc measurements mathematically independent of titer had relatively little impact on predictive performance. Similar analyses for a distinct SIV vaccine study also showed that Fab‐Fc measurements performed significantly better than titer. These results suggest that predictive modeling with measurements of antibody properties can provide detailed correlates with robust predictive power, suggest directions for vaccine improvement, and potentially enable discovery of mechanistic associations

Safety and tolerability of HIV-1 multiantigen pDNA vaccine given with IL-12 plasmid DNA via electroporation, boosted with a recombinant vesicular stomatitis virus HIV Gag vaccine in healthy volunteers in a randomized, controlled clinical trial.

BACKGROUND:The addition of plasmid cytokine adjuvants, electroporation, and live attenuated viral vectors may further optimize immune responses to DNA vaccines in heterologous prime-boost combinations. The objective of this study was to test the safety and tolerability of a novel prime-boost vaccine regimen incorporating these strategies with different doses of IL-12 plasmid DNA adjuvant. METHODS:In a phase 1 study, 88 participants received an HIV-1 multiantigen (gag/pol, env, nef/tat/vif) DNA vaccine (HIV-MAG, 3000 μg) co-administered with IL-12 plasmid DNA adjuvant at 0, 250, 1000, or 1500 μg (N = 22/group) given intramuscularly with electroporation (Ichor TriGrid™ Delivery System device) at 0, 1 and 3 months; followed by attenuated recombinant vesicular stomatitis virus, serotype Indiana, expressing HIV-1 Gag (VSV-Gag), 3.4 ⊆ 107 plaque-forming units (PFU), at 6 months; 12 others received placebo. Injections were in both deltoids at each timepoint. Participants were monitored for safety and tolerability for 15 months. RESULTS:The dose of IL-12 pDNA did not increase pain scores, reactogenicity, or adverse events with the co-administered DNA vaccine, or following the VSV-Gag boost. Injection site pain and reactogenicity were common with intramuscular injections with electroporation, but acceptable to most participants. VSV-Gag vaccine often caused systemic reactogenicity symptoms, including a viral syndrome (in 41%) of fever, chills, malaise/fatigue, myalgia, and headache; and decreased lymphocyte counts 1 day after vaccination. CONCLUSIONS:HIV-MAG DNA vaccine given by intramuscular injection with electroporation was safe at all doses of IL-12 pDNA. The VSV-Gag vaccine at this dose was associated with fever and viral symptoms in some participants, but the vaccine regimens were safe and generally well-tolerated. TRIAL REGISTRATION:Clinical Trials.gov NCT01578889