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1.
J Pediatr Urol ; 11(6): 358.e1-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26271822

ABSTRACT

BACKGROUND: Post-surgical infections (PSIs) are a source of preventable perioperative morbidity. No guidelines exist for the use of perioperative antibiotics in pediatric urologic procedures. OBJECTIVE: This study reports the rate of PSIs in non-endoscopic pediatric genitourinary procedures at our institution. Secondary aims evaluate the association of PSI with other perioperative variables, including wound class (WC) and perioperative antibiotic administration. STUDY DESIGN: Data from consecutive non-endoscopic pediatric urologic procedures performed between August 2011 and April 2014 were examined retrospectively. The primary outcome was the rate of PSIs. PSIs were classified as superficial skin (SS) and deep/organ site (D/OS) according to Centers for Disease Control and Prevention guidelines, and urinary tract infection (UTI). PSIs were further stratified by WC1 and WC2 and perioperative antibiotic usage. A relative risk and chi-square analysis compared PSI rates between WC1 and WC2 procedures. RESULTS: A total of 1185 unique patients with 1384 surgical sites were reviewed; 1192 surgical sites had follow-up for inclusion into the study. Ten total PSIs were identified, for an overall infection rate of 0.83%. Of these, six were SS, one was D/OS, and three were UTIs. The PSI rate for WC1 (885 sites) and WC2 (307 sites) procedures was 0.34% and 2.28%, respectively, p < 0.01. Relative risk of infection in WC2 procedures was 6.7 (CI 1.75-25.85, p = 0.0055). The rate of infections in WC1 procedures was similar between those receiving and not receiving perioperative antibiotics (0.35% vs. 0.33%). All WC2 procedures received antibiotics. DISCUSSION: Post-surgical infections are associated with significant perioperative morbidity. In some studies, PSI can double hospital costs, and contribute to hospital length of stay, admission to intensive care units, and impact patient mortality. Our study demonstrates that the rate of PSI in WC1 operations is low, irrespective of whether the patient received perioperative antibiotics (0.35%) or no antibiotics (0.33%). WC2 operations were the larger source of morbidity with an infection rate of 2.28% and a 6.7 fold higher increase in relative risk. CONCLUSIONS: WC1 procedures have a rate of infection around 0.3%, which is independent of the use of perioperative antibiotics. WC2 procedures have a higher rate of infection, with a relative risk of 6.7 for the development of PSI, and should be the target of guidelines for periprocedural prophylaxis.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis , Surgical Wound Infection/prevention & control , Urinary Tract Infections/prevention & control , Urogenital Surgical Procedures , Child, Preschool , Female , Humans , Male , Retrospective Studies
2.
BMJ Case Rep ; 20152015 Jan 06.
Article in English | MEDLINE | ID: mdl-25564631

ABSTRACT

Polyorchidism, or more than one testicle in a hemiscrotum, is a relatively rare phenomenon. It is often associated with several other conditions, including inguinal hernia, testicular maldescent, testicular torsion, hydrocele or hypospadias. In this report, we describe a patient who presented with three testicles in one hemiscrotum, which is a highly unusual presentation for an already uncommon condition. We also review the relevant literature as it relates to the need for surveillance due to the increased risk for malignancy.


Subject(s)
Testis/abnormalities , Testis/pathology , Adolescent , Biopsy , Humans , Male , Testis/surgery
4.
Urology ; 81(1): 209.e9-14, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23153940

ABSTRACT

OBJECTIVE: To assess the ability of daily oral simvastatin administration to reduce the negative urodynamic changes associated with cyclophosphamide (CP)-induced cystitis and to prevent bladder inflammation. Patients undergoing CP chemotherapy frequently develop cystitis, leading to urinary dysfunction and hemorrhage. Recent studies have suggested statins possess anti-inflammatory properties and might be uroprotective. MATERIALS AND METHODS: Urodynamic properties were analyzed in 4 groups of female Sprague-Dawley rats: group 1, vehicle (300 µL, 0.5% methylcellulose, orally for 7 days); group 2, simvastatin (1 mg/rat/d); group 3, vehicle plus CP (intraperitoneally 80 mg/kg, 24 h before cystometry); and group 4, simvastatin plus CP. The inflammation in the groups was assessed using Evans blue extravasation. RESULTS: CP stimulated significant increases in the number of nonvoiding contractions (0.83±0.26 vs 4.97±1.90; P=.03) and decreases in the peak voiding pressure (53.46±5.08 vs 33.34±4.37 cm H2O; P=.01). Simvastatin returned these parameters to the control levels of 1.62±0.73 (P=.70) and 45.98±7.78 cm H2O (P=.38). CP at this level caused a slight, but significant, increase in the voided volume (0.82±0.13 vs 1.16±0.14 mL; P=.04), which returned to control levels (0.74±0.12 mL; P=.65) with simvastatin. Other urodynamic parameters, such as the threshold pressure, were not affected by simvastatin or CP, or the combination of the 2. CP-induced inflammation in the bladder (Evans blue extravasation) was suppressed by simvastatin. CONCLUSION: Simvastatin was effective at ameliorating the negative urodynamic changes and inflammation in the bladder after CP administration and is a potential therapy for preventing side effects in patients undergoing this chemotherapy.


Subject(s)
Antineoplastic Agents, Alkylating/adverse effects , Cyclophosphamide/adverse effects , Cystitis/prevention & control , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Simvastatin/pharmacology , Urodynamics/drug effects , Animals , Cystitis/chemically induced , Cystitis/physiopathology , Female , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Muscle Contraction/drug effects , Pressure , Rats , Rats, Sprague-Dawley , Simvastatin/therapeutic use , Urinary Bladder/drug effects , Urination/drug effects , Urine
5.
Am J Physiol Gastrointest Liver Physiol ; 302(3): G336-42, 2012 Feb 01.
Article in English | MEDLINE | ID: mdl-22094601

ABSTRACT

Steatotic livers are sensitive to ischemic events and associated ATP depletion. Hepatocellular necrosis following these events may result from mitochondrial uncoupling protein-2 (UCP2) expression. To test this hypothesis, we developed a model of in vitro steatosis using primary hepatocytes from wild-type (WT) and UCP2 knockout (KO) mice and subjected them to hypoxia/reoxygenation (H/R). Using cultured hepatocytes treated with emulsified fatty acids for 24 h, generating a steatotic phenotype (i.e., microvesicular and broad-spectrum fatty acid accumulation), we found that the phenotype of the WT and UCP2 KO were the same; however, cellular viability was increased in the steatotic KO hepatocytes following 4 h of hypoxia and 24 h of reoxygenation; Hepatocellular ATP levels decreased during hypoxia and recovered after reoxygenation in the control and UCP2 KO steatotic hepatocytes but not in the WT steatotic hepatocytes; mitochondrial membrane potential in WT and UCP2 KO steatotic groups was less than control groups but higher than UCP2 KO hepatocytes. Following reoxygenation, lipid peroxidation, as measured by thiobarbituric acid reactive substances, increased in all groups but to a greater extent in the steatotic hepatocytes, regardless of UCP2 expression. These results demonstrate that UCP2 sensitizes steatotic hepatocytes to H/R through mitochondrial depolarization and ATP depletion but not lipid peroxidation.


Subject(s)
Cell Hypoxia/physiology , Fatty Liver , Hepatocytes/pathology , Ion Channels/deficiency , Mitochondrial Proteins/deficiency , Oxygen/pharmacology , Adenosine Triphosphate/metabolism , Animals , Cell Death/drug effects , Cell Survival/drug effects , Cells, Cultured , Emulsions/pharmacology , Fatty Acids/metabolism , Hepatocytes/drug effects , Hepatocytes/metabolism , Ion Channels/genetics , Ion Channels/metabolism , Lipid Peroxidation/drug effects , Membrane Potential, Mitochondrial/drug effects , Mice , Mice, Inbred Strains , Mice, Knockout , Mice, Obese , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Phospholipids/pharmacology , Soybean Oil/pharmacology , Uncoupling Protein 2
6.
Liver Transpl ; 17(9): 1089-98, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21563297

ABSTRACT

Kupffer cells (KCs) have been shown to be critical mediators of ischemia/reperfusion (I/R) injury in the murine liver. Using liposomal clodronate (LC), we found that KCs were protective in models of total hepatic ischemia with bowel congestion. We investigated the role of toll-like receptor 4 (TLR4) in the damage that occurs after I/R in KC-depleted livers. We injected 8-week-old C57BL/10J mice and C57BL/10ScN [toll-like receptor 4 knockout (TLR4KO)] mice with LC 48 hours before 35 minutes of warm hepatic ischemia with bowel congestion, which was followed by either 6 or 24 hours of reperfusion. The KC-depleted animals had increased mortality as well as a 10-fold increase in their aminotransferase levels that correlated with increases in centrilobular necrosis. These changes were absent in the TLR4KO animals. Lipopolysaccharide was bound extensively to endothelial cells after I/R, and this binding was diminished in the TLR4KO animals. In conjunction with this, there was an up-regulation of endothelial cell adhesion molecules in the LC-treated animals that was absent in the TLR4KO animals. Finally, there was a dramatic increase in the proinflammatory cytokine levels of the LC-treated animals, and the TLR4KO animals were protected against this increase. In conclusion, TLR4 promotes endothelial overactivation after I/R in the absence of KCs.


Subject(s)
Endothelial Cells/metabolism , Kupffer Cells/cytology , Liver/pathology , Mice, Knockout , Reperfusion Injury/pathology , Toll-Like Receptor 4/genetics , Alanine Transaminase/blood , Animals , Cell Adhesion , Cytokines/metabolism , Dendritic Cells/cytology , Ischemia/pathology , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Microscopy, Confocal/methods , Necrosis
7.
J Immunol ; 184(10): 5849-58, 2010 May 15.
Article in English | MEDLINE | ID: mdl-20400698

ABSTRACT

Kupffer cells (KCs) are thought to mediate hepatocyte injury via their production of proinflammatory cytokines and reactive oxygen species in response to stress. In this study, we depleted KCs from the liver to examine their role in total warm hepatic ischemia/reperfusion (I/R) injury with bowel congestion. We injected 8-wk-old C57BL/10J mice with liposome-encapsulated clodronate 48 h before 35 min of hepatic ischemia with bowel congestion, followed by 6 or 24 h of reperfusion. KC-depleted animals had a higher mortality rate than diluent-treated animals and a 10-fold elevation in transaminase levels that correlated with increases in centrilobular necrosis. There was extensive LPS binding to the endothelial cells, which correlated with an upregulation of endothelial adhesion molecules in the KC-depleted animals versus diluent-treated animals. There was an increase in the levels of proinflammatory cytokines in KC-depleted animals, and a concomitant decrease in IL-10 levels. When KC-depleted mice were treated with recombinant IL-10, their liver damage profile in response to I/R was similar to diluent-treated animals, and endothelial cell adhesion molecules and proinflammatory cytokine levels decreased. KCs are protective in the liver subjected to total I/R with associated bowel congestion and are not deleterious as previously thought. This protection appears to be due to KC secretion of the potent anti-inflammatory cytokine IL-10.


Subject(s)
Interleukin-10/physiology , Intestinal Mucosa/immunology , Intestinal Mucosa/pathology , Kupffer Cells/immunology , Kupffer Cells/pathology , Liver Transplantation/immunology , Liver Transplantation/pathology , Reperfusion Injury/immunology , Animals , Biological Transport/immunology , Cell Death/drug effects , Cell Death/immunology , Clodronic Acid/administration & dosage , Disease Models, Animal , Dose-Response Relationship, Immunologic , Endothelium, Vascular/immunology , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Intestinal Mucosa/drug effects , Ischemia/immunology , Ischemia/mortality , Ischemia/pathology , Kupffer Cells/drug effects , Lipopolysaccharides/metabolism , Lipopolysaccharides/toxicity , Liposomes/administration & dosage , Liver Transplantation/mortality , Male , Mice , Mice, Inbred C57BL , Reperfusion Injury/mortality , Reperfusion Injury/pathology , Survival Analysis
8.
Fam Med ; 42(1): 16-8, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20063215

ABSTRACT

BACKGROUND AND OBJECTIVES: There are currently more than 100 student-run medical clinics in the United States, operated in conjunction with various allopathic medical schools. However, there have been no reports regarding patient satisfaction with these free clinic services. METHODS: Fifty-two of 60 patients seen at the C.A.R.E.S. clinic over a 4-week period in the winter of 2007 completed a questionnaire. RESULTS: Patients were highly satisfied with laboratory services, staff friendliness, amount of time spent being interviewed, and the depth of the explanations. They were less satisfied with the hours of operation and wait time. CONCLUSIONS: Patients seen at a student-run clinic are very satisfied with the services they received.


Subject(s)
Ambulatory Care Facilities/organization & administration , Education, Medical/methods , Health Services Accessibility , Patient Satisfaction/statistics & numerical data , Students, Medical , Adult , Ambulatory Care Facilities/trends , Education, Medical/trends , Female , Humans , Male , Medically Uninsured , Middle Aged , Schools, Medical/organization & administration , Schools, Medical/trends , South Carolina , Workforce , Young Adult
9.
J Immunol ; 183(7): 4764-72, 2009 Oct 01.
Article in English | MEDLINE | ID: mdl-19752222

ABSTRACT

Hepatic steatosis typically renders the donor organ unusable, as donor organs with >30% steatosis are more likely to develop graft failure. The mechanisms leading to failure are not well defined, but steatosis enhances hepatic susceptibility to ischemia reperfusion injury (IRI). We investigated the role of complement in hepatic IRI in lean and steatotic (diet-induced) mice. Steatotic mice were significantly more susceptible to total warm hepatic IRI than lean mice as determined by serum alanine aminotransferase, histopathologically assessed damage, and 24-h survival. C3 deficiency protected both lean and steatotic mice from IRI, as determined by all measured outcomes. Furthermore, treatment of wild-type mice with the complement inhibitor CR2-Crry provided protection equivalent to that seen in C3-deficient mice. Importantly, although steatotic livers were much more susceptible to IRI than lean livers, by most measures there was no statistical difference between the level of IRI to steatotic or lean livers when complement was inhibited. To investigate the clinical relevance of these findings in the context of transplantation, we treated recipients of lean or steatotic liver grafts with saline or CR2-Crry. There was a marked reduction in graft inflammation and injury and significantly improved 7-day survival in CR2-Crry-treated recipients of either lean or steatotic grafts. These data indicate that complement plays a key role in the enhanced susceptibility of steatotic livers to IRI and suggest that complement inhibition represents a potential strategy to reduce the donor shortage by allowing the more routine use of marginal steatotic donor livers.


Subject(s)
Complement C3/physiology , Fatty Liver/immunology , Liver/blood supply , Liver/immunology , Reperfusion Injury/immunology , Animals , Complement C3/antagonists & inhibitors , Complement C3/deficiency , Dietary Fats/administration & dosage , Disease Susceptibility/immunology , Fatty Liver/surgery , Graft Rejection/immunology , Liver Transplantation/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Recombinant Fusion Proteins/physiology , Reperfusion Injury/prevention & control , Reperfusion Injury/surgery
10.
Liver Transpl ; 15(9): 1101-9, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19718644

ABSTRACT

Steatotic donors are routinely rejected for transplantation because of their increased rate of primary nonfunction. These grafts are more sensitive to ischemia/reperfusion (I/R) during transplantation. Removal of endotoxin before reperfusion improves liver performance post-I/R. We hypothesize that the main modality of injury in steatotic livers is toll-like receptor 4 (TLR4) signaling. We fed 4-week-old control and TLR4-deficient (TLR4KO) mice a normal diet (ND) or a 60% high-fat diet (HFD) for 4 weeks to induce steatosis. Mice were subjected to total hepatic ischemia (35 minutes) and reperfusion (1 or 24 hours). Survival improved and liver pathology decreased at 24 hours in TLR4KO HFD animals compared to control HFD animals. An investigation of infiltrates showed that neutrophils and CD4+ cells were increased at 24 hours in control HFD animals, whereas TLR4KO HFD animals were similar to ND controls. Messenger RNA levels of interleukin 6 (IL-6), IL-12, and interferon gamma were elevated at 1 hour in control HFD animals, whereas TLR4KO HFD animals were similar to ND controls. IL-10 levels at 1 hour of reperfusion in control HFD and TLR4KO animals were decreased versus control ND animals. In conclusion, these improvements in liver function in TLR4KO HFD animals implicate TLR4 as a mediator of steatotic graft failure after I/R.


Subject(s)
Fatty Liver/surgery , Liver Transplantation/adverse effects , Liver/blood supply , Liver/immunology , Liver/surgery , Primary Graft Dysfunction/immunology , Reperfusion Injury/immunology , Toll-Like Receptor 4/metabolism , Warm Ischemia/adverse effects , Animals , CD4-Positive T-Lymphocytes/immunology , Cell Death , Disease Models, Animal , Endotoxins/blood , Fatty Liver/immunology , Fatty Liver/pathology , Inflammation Mediators/metabolism , Interferon-gamma/genetics , Interleukin-10/genetics , Interleukin-12/genetics , Interleukin-6/genetics , Liver/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Neutrophil Infiltration , Primary Graft Dysfunction/pathology , RNA, Messenger/metabolism , Reperfusion Injury/pathology , Time Factors , Toll-Like Receptor 4/deficiency , Toll-Like Receptor 4/genetics
11.
Obesity (Silver Spring) ; 17(2): 402-4, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18948969

ABSTRACT

With increasing incidence of obesity, there is greater demand for suitable research and therapeutic models. The ob/ob mouse model develops obesity by 5 weeks of age. Previously, a method using DNA purification, PCR, and restriction digestion of products was devised to identify mice bearing the ob allele. Here, we describe a direct PCR method that requires no DNA purification. Wild-type and ob-specific primers are used under the same conditions in two separate and simultaneously run three-primer PCRs. Standard PCR using the wild-type primer mix produces 191 bp and 104 bp bands in +/+ and ob/+ and only the control 191 bp band in ob/ob animals. The ob-specific primer reaction produces 191 bp and 123 bp bands in ob/+ and ob/ob and only the control 191 bp band in +/+ animals. Phenotypic weight gain in offspring of heterozygous intercrosses was used to validate genotypes. This primer-specific PCR method allows simultaneous identification of +/+, ob/+, and ob/ob genotypes prior to breeding age to facilitate breeding and research studies in an important model of clinical obesity.


Subject(s)
Mice, Obese/genetics , Mutation/genetics , Obesity/genetics , Polymerase Chain Reaction/methods , Alleles , Animals , DNA/genetics , Disease Models, Animal , Genetic Predisposition to Disease/genetics , Genotype , Mice
12.
Transplantation ; 86(2): 286-92, 2008 Jul 27.
Article in English | MEDLINE | ID: mdl-18645492

ABSTRACT

BACKGROUND: Hormonal resuscitation, specifically administration of levothyroxine (T4) and methylprednisolone (steroid, i.e., the "T4 Protocol") in organ transplant donors, is becoming increasingly used. Previous studies have shown that this maximizes the number of usable organs by reducing metabolic disturbances post-brain death. However, anecdotal evidence has shown that steatotic livers are adversely affected by this protocol. Therefore, we sought to investigate the hypothesis that the use of T4 and steroid is detrimental to steatotic livers in a model of total hepatic warm ischemia-reperfusion (I/R). METHODS: We subjected 8- to -10-week-old male C57BL/6 and ob/ob mice to injections of T4 and steroid 48 hr before 15 min of total hepatic ischemia, followed by 24 hr of reperfusion. RESULTS: We saw a significant decrease in survival in ob/ob animals given T4 and steroid as compared with single-treated or vehicle-treated animals. This decrease in survival was accompanied by a dramatic increase in liver necrosis (as measured on a scale from 0 to 3) in these animals as compared with controls. Previous work in our lab has shown that uncoupling protein-2 is a major mediator of I/R in steatotic animals, as it upsets normal energy homeostasis. Following with this hypothesis, we see a dramatic increase in uncoupling protein-2 levels in the combination treated animals, which is accompanied by a concomitant decrease in ATP levels after reperfusion. CONCLUSIONS: The T4 protocol is detrimental to steatotic livers subjected to I/R, likely because of a decreased ability to recover after reperfusion caused by decreased ability to form ATP.


Subject(s)
Fatty Liver/drug therapy , Reperfusion Injury/drug therapy , Adenosine Triphosphate/metabolism , Alanine Transaminase/blood , Animals , Liver/pathology , Liver Transplantation/methods , Male , Methylprednisolone/administration & dosage , Mice , Mice, Inbred C57BL , Necrosis/pathology , Reperfusion , Thyroxine/administration & dosage , Time Factors
13.
J Biol Chem ; 283(13): 8573-9, 2008 Mar 28.
Article in English | MEDLINE | ID: mdl-18086675

ABSTRACT

Steatotic livers are not used for transplantation because they have a reduced tolerance for ischemic events with reduced ATP levels and greater levels of cellular necrosis, which ultimately result in total organ failure. Mitochondrial uncoupling protein-2 (UCP2) is highly expressed in steatotic livers and may be responsible for liver sensitivity to ischemia through mitochondrial and ATP regulation. To test this hypothesis, experiments were conducted in lean and steatotic (ob/ob), wild-type, and UCP2 knock-out mice subjected to total warm hepatic ischemi-a/reperfusion. Although ob/ob UCP2 knock-out mice and ob/ob mice have a similar initial phenotype, ob/ob UCP2 knock-out animal survival was 83% when compared with 30% in ob/ob mice 24 h after reperfusion. Serum alanine aminotransferase concentrations and hepatocellular necrosis were decreased in the ob/ob UCP2 knock-out mice when compared with ob/ob mice subjected to ischemia. Liver ATP levels were increased in the ob/ob UCP2 knock-out animals after reperfusion when compared with the ob/ob mice but remained below the concentrations from lean livers. Lipid peroxidation (thiobarbituric acid-reactive substances) increased after reperfusion most significantly in the steatotic groups, but the increase was not affected by UCP2 deficiency. These results reveal that UCP2 expression is a critical factor, which sensitizes steatotic livers to ischemic injury, regulating liver ATP levels after ischemia and reperfusion.


Subject(s)
Fatty Liver/metabolism , Fatty Liver/pathology , Ion Channels/metabolism , Mitochondrial Proteins/metabolism , Reperfusion Injury/metabolism , Adenosine Triphosphate/metabolism , Animals , Fatty Liver/genetics , Female , Ion Channels/deficiency , Ion Channels/genetics , Lipid Peroxidation , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Mitochondrial Proteins/deficiency , Mitochondrial Proteins/genetics , Phenotype , Reperfusion Injury/genetics , Survival Rate , Uncoupling Protein 2
14.
Mol Ther ; 12(2): 360-8, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16043104

ABSTRACT

Protection of transplanted pancreatic islet grafts in recipients with autoimmune diabetes depends on the suppression of autoimmune recurrence and allogeneic rejection. The aim of this study was to investigate the efficiency of viral IL-10 gene delivery in the prevention of autoimmune recurrence following islet transplantation. We evaluated the effectiveness of a systemically delivered adeno-associated viral vector (AAV vIL-10) carrying viral IL-10 in protecting islet engraftment. We observed significant prolongation of graft survival after treatment with AAV vIL-10 when using islets from donors lacking autoimmunity. We found that the mechanism of vIL-10-mediated protection was associated with suppression of T cell activation and that donor immune cells that were simultaneously transferred with the islet grafts could induce autoimmune recurrence. AAV vIL-10 gene transfer suppressed previously activated T cells and protected grafted islets from autoimmune-mediated destruction. We conclude that vIL-10 can regulate autoimmune activity and that transfer of its gene may have potential for therapeutic islet transplantation.


Subject(s)
Autoimmunity , Diabetes Mellitus, Type 1/therapy , Genetic Therapy , Interleukin-10/therapeutic use , Islets of Langerhans Transplantation/immunology , Adenoviridae/genetics , Animals , Diabetes Mellitus, Type 1/immunology , Diabetes Mellitus, Type 1/prevention & control , Female , Genetic Vectors , Graft Survival , Interleukin-10/genetics , Lymphocyte Activation/physiology , Mice , Mice, Inbred NOD , Secondary Prevention , T-Lymphocytes/immunology , Transfection , Transplantation, Isogeneic
15.
Am J Transplant ; 5(3): 475-83, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15707401

ABSTRACT

The pathogenesis of pancreatic beta-cell death in diabetes mellitus is still under investigation. Inflammation is likely to be one of the factors responsible for beta-cell death during disease development. In this study, we have used a novel antiinflammatory compound, Lisofylline (LSF), to investigate the role of inflammatory blockade in protecting human pancreatic islets. LSF is a small synthetic molecule that reduces inflammatory cytokine production and action, improves beta-cell mitochondrial metabolism, and regulates immune activities. The present study has demonstrated that the treatment of human islets with LSF not only allows the retention of glucose responsiveness and insulin secretion in the presence of multiple proinflammatory cytokines, but also enhances basal insulin secretion of beta cells in vitro. LSF also significantly reduces islet apoptosis, protects beta cells from proinflammatory cytokine damage, and maintains cellular viability. In a mouse transplantation model, insulin independence could be reached in diabetic recipient mice by implantation of 30% fewer islets when LSF was used in islet culture compared to the control group. These results demonstrate that LSF profoundly enhances beta-cell function, and suggest the potential of using inflammatory blockade, such as LSF, to improve beta-cell function for islet transplantation.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Islets of Langerhans/drug effects , Pentoxifylline/analogs & derivatives , Pentoxifylline/pharmacology , Apoptosis/drug effects , Cell Survival/drug effects , Cell Survival/immunology , DNA-Binding Proteins/metabolism , Female , Glucose/metabolism , Humans , Inflammation/drug therapy , Inflammation/immunology , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/immunology , Islets of Langerhans/metabolism , Islets of Langerhans Transplantation , Male , Phosphorylation , STAT4 Transcription Factor , Trans-Activators/metabolism
16.
J Autoimmun ; 22(3): 191-200, 2004 May.
Article in English | MEDLINE | ID: mdl-15041039

ABSTRACT

Signal transducers and activators of transcription (STAT) proteins are activated in response to many cytokines, growth factors and hormones. STAT4 mediates IL-12 signaling and regulates T helper 1 (Th1) cell differentiation. Both IL-12 and Th1 cell activation participate in the development of autoimmune diabetes. In this study, we investigated the role of STAT4 in autoimmune diabetes. We crossbred Stat4 deficient (Stat4-/-) mice with nonobese diabetic (NOD) mice to generate the Stat4-/- NOD model. In Stat4-/- NOD mice, serum levels of both IFN-gamma and IL-2 were significantly reduced as compared to the controls. Insulin secretion in pancreatic islets was preserved in Stat4-/- NOD mice. Significantly, disruption of Stat4 activation completely prevented the development of spontaneous diabetes in NOD mice. This study reveals the important role of STAT4 in autoimmune diabetes pathogenesis.


Subject(s)
DNA-Binding Proteins/genetics , Diabetes Mellitus, Type 1/genetics , Trans-Activators/genetics , Animals , Cytokines/biosynthesis , DNA-Binding Proteins/deficiency , DNA-Binding Proteins/immunology , Diabetes Mellitus, Type 1/immunology , Diabetes Mellitus, Type 1/metabolism , Disease Models, Animal , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/metabolism , Mice , Mice, Congenic , Mice, Inbred NOD , STAT4 Transcription Factor , Time Factors , Trans-Activators/deficiency , Trans-Activators/immunology
17.
Transplantation ; 77(1): 55-60, 2004 Jan 15.
Article in English | MEDLINE | ID: mdl-14724435

ABSTRACT

BACKGROUND: Pancreatic islet transplantation has become a promising treatment for type 1 diabetes. However, autoimmune reactivity destroys engrafted islets in type 1 diabetic recipients. The authors' previous studies demonstrated that a novel anti-inflammatory agent, lisofylline (LSF), suppressed autoimmune reactivity and protected nonobese diabetic (NOD) mice from diabetes. In this study, the authors investigated the potential of LSF in preventing autoimmune diabetes recurrence after islet transplantation. METHODS: Spontaneously diabetic NOD mice received NOD severe combined immunodeficiency islet transplants and were treated with daily LSF injections at 50 mg/kg for 3 weeks. Blood glucose levels were monitored. Serum cytokine levels were measured at 1 and 3 weeks after engraftment. Nephrectomy of the islet-implanted kidney was performed in LSF-treated recipients. Histology of islet grafts was assessed at the end of the study. The effect of LSF on beta-cell function was studied in vitro. RESULTS: Without immunosuppressants and insulin, the LSF-treated recipient mice maintained euglycemia significantly longer than the saline-treated recipients (mean, >65 days in the LSF-treated group vs. 6 days in saline controls; P=0.0004). Serum levels of interferon-gamma were markedly reduced in LSF-treated recipients at 1 and 3 weeks posttransplant. Diabetes recurred in the LSF-treated recipients after removing the islet-implanted kidneys. Immunohistochemistry showed retention of insulin-positive cells in the grafts of the LSF-treated recipients. LSF preserved beta-cell insulin secretory function in the presence of inflammatory cytokines in vitro. CONCLUSIONS: This study demonstrates that autoimmune diabetes recurrence after islet transplantation could be prevented by treatment with LSF. LSF and its analogues may have the potential to prevent islet autoimmune destruction in clinical transplantation.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Diabetes Mellitus, Type 1/prevention & control , Diabetes Mellitus, Type 1/surgery , Islets of Langerhans Transplantation , Pentoxifylline/analogs & derivatives , Pentoxifylline/pharmacology , Secondary Prevention , Animals , Apoptosis/drug effects , Cytokines/antagonists & inhibitors , Cytokines/classification , Cytokines/metabolism , Female , Graft Survival/drug effects , Inflammation Mediators/antagonists & inhibitors , Inflammation Mediators/blood , Inflammation Mediators/metabolism , Insulin/metabolism , Insulin Secretion , Islets of Langerhans/drug effects , Islets of Langerhans/metabolism , Islets of Langerhans/physiopathology , Mice , Mice, Inbred NOD , Mice, SCID , Time Factors , Transplantation, Homologous
18.
Ann N Y Acad Sci ; 1005: 409-11, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14679102

ABSTRACT

We investigated the signal transduction pathway of IL-12 and showed that lisofylline (LSF) inhibited the signal transducer and activator of transcription factor-4 (STAT4) activation. Interruption of IL-12-mediated STAT4 activation prevented autoimmune diabetes in NOD mice.


Subject(s)
DNA-Binding Proteins/antagonists & inhibitors , Diabetes Mellitus, Type 1/prevention & control , Immunosuppressive Agents/pharmacology , Pentoxifylline/analogs & derivatives , Pentoxifylline/pharmacology , Trans-Activators/antagonists & inhibitors , DNA-Binding Proteins/metabolism , Humans , Interleukin-12/metabolism , Phosphorylation , STAT4 Transcription Factor , Signal Transduction , Trans-Activators/metabolism
19.
Clin Immunol ; 107(1): 30-5, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12738247

ABSTRACT

FTY720 is a novel immune regulatory drug derived from the fungal sphingosine analog ISP-1 (myriocin). FTY720 causes a redistribution of lymphocytes from circulation to secondary lymphoid tissues. Type 1 diabetes is an autoimmune disorder caused by cellular-mediated destruction of insulin-producing pancreatic beta cells in the islets of Langerhans. Indeed, local infiltration of islets by mononuclear cells is the hallmark of Type 1 diabetes. Based on both FTY720's action and the involvement of cellular infiltration in the disease progression, we tested FTY720 for its ability to prevent autoimmune diabetes in diabetes-prone, nonobese diabetic (NOD) mice. We found that treatment with FTY720 completely prevented NOD mice from developing autoimmune diabetes. The FTY720-treated animals showed both reduced numbers of circulating lymphocytes and sharply diminished cellular infiltration of pancreatic islets. These results suggest that FTY720 may be effective in prevention of autoimmune diabetes or in slowing its progression.


Subject(s)
Diabetes Mellitus, Type 1/prevention & control , Immunosuppressive Agents/pharmacology , Propylene Glycols/pharmacology , Animals , Diabetes Mellitus, Type 1/immunology , Female , Fingolimod Hydrochloride , Glucose/metabolism , Immunohistochemistry , Insulin/metabolism , Islets of Langerhans/drug effects , Islets of Langerhans/immunology , Islets of Langerhans/metabolism , Lymphocyte Count , Male , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Random Allocation , Sphingosine/analogs & derivatives
20.
Pancreas ; 26(4): e99-104, 2003 May.
Article in English | MEDLINE | ID: mdl-12717280

ABSTRACT

INTRODUCTION: Proinflammatory cytokines play an important role in the development of type 1 diabetes. Lisofylline (LSF) is a novel anti-inflammatory compound that specifically inhibits proinflammatory cytokine production and action. AIM: To investigate the effect of LSF on diabetes prevention. METHODOLOGY: A mouse with diabetes induced by multiple low doses of streptozotocin (STZ) can be used as an animal model for type 1 diabetes. In this study, we used this method to induce diabetes in C57BL/6J mice. The daily LSF treatment started 5 days before STZ injections and lasted for 2 weeks. The incidence of diabetes was monitored. Insulin secretion was assessed in pancreatic islets isolated from experimental mice. Cytokine production was measured in mouse sera. Islet apoptosis was assessed quantitatively. RESULTS: In LSF-treated mice, there was a significant reduction of diabetes incidence (25% vs. 91.6%). This protection was associated with suppression of systemic levels of IFN-gamma and TNF-alpha, inhibition of macrophage infiltration in islets, restoration of islet insulin secretion, and reduction of beta-cell apoptosis. CONCLUSIONS: This study suggests that treatment with LSF suppresses proinflammatory cytokines and protects beta-cells from inflammation. LSF may be useful for prevention of type 1 diabetes and other disorders associated with excessive proinflammatory cytokines.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Diabetes Mellitus, Experimental/prevention & control , Pentoxifylline/analogs & derivatives , Pentoxifylline/therapeutic use , Animals , Antigens, Differentiation/analysis , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/chemically induced , Dose-Response Relationship, Drug , Enzyme-Linked Immunosorbent Assay , Immunohistochemistry , Insulin/analysis , Insulin/metabolism , Insulin Secretion , Interferon-gamma/blood , Interleukin-10/blood , Interleukin-4/blood , Islets of Langerhans/chemistry , Islets of Langerhans/drug effects , Islets of Langerhans/metabolism , Male , Mice , Mice, Inbred C57BL , Random Allocation , Streptozocin/administration & dosage , Tumor Necrosis Factor-alpha/metabolism
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