William R. Gower

Tissue-Specific Cytokine Production During Experimental Acute Pancreatitis (A Probable Mechanism for Distant Organ Dysfunction)

Our purpose was to determine if cytokines are produced systemically during acute pancreatitis. Proinflammatory cytokines are elevated during acute pancreatitis and have been implicated in the progression of pancreatitis-associated multiple organ dysfunction. Whether these mediators are produced within all tissues or very few specific organs is not known. Edematous pancreatitis was induced in adult male mice by IP injection of cerulein. Necrotizing pancreatitis was induced in young female mice by feeding a choline-deficient, ethionine supplemented diet.Animals were sacrificed as pancreatitis worsened, with multiple organs prepared for tissue mRNA and protein analysis by RT-PCR and immunoblotting.Pancreatitis severity was established by histologic grading and serum amylase and lipase. There was no cytokine mRNA or protein detectable prior to the induction of pancreatitis. Tumor necrosis factor-α (TNF-α) and interleukin-1-β (IL-1β) mRNA and protein were detected within the pancreas early in the course of pancreatitis in both models,coinciding with the development of hyperamylasemia (both P < 0.001). Interleukin-6 was produced in the pancreas after pancreatitis was more fully developed (P< 0.001). IL-1β and TNF-α were subsequently produced in large amounts in lung, liver, and spleen but never within kidney, cardiac muscle, or skeletal muscle.A significant delay between pancreatic and distant organ cytokine production was always observed.It is concluded that proinflammatory cytokines are produced within the pancreas and within organs known to develop dysfunction during severe pancreatitis. Cytokine production is tissue specific,correlates with disease severity, and occurs within the pancreas first and subsequently within distant organs.

Three peptides from the atrial natriuretic factor prohormone amino terminus lower blood pressure and produce diuresis, natriuresis, and/or kaliuresis in humans.

BackgroundThree peptides consisting of amino acids 1-30, 31-67, and 79-98 of the 126–amino acid atrial natriuretic factor prohormone (proANF), which have blood pressure-lowering, diuretic, natriuretic, and/or kaliuretic properties in animals, were investigated to determine if they have similar properties in humans. Methods and ResultsThirty-six healthy, normotensive human volunteers (18 men and 18 women, ages 20 to 58 years) were divided into six similar groups based on age, sex, weight, blood pressure, and heart rate. After a 60-minute baseline period, 100 ng of proANFs 1-30, 31-67, 79-98, or ANF/kg body wt per minute was given intravenously for 60 minutes followed by a 3-hour postinfusion data collection period. Each of the atrial natriuretic peptides decreased systolic and diastolic blood pressures (P<.05), with proANF 31-67 causing the largest decrease. Urine flow increased 4- to 12-fold and was still significantly increased (P<.01) for 2 to 3 hours after stopping the respective infusions of proANFs 1-30, 31-67, and 79-98. Atrial natriuretic factor (ANF) increased urine flow 4- to 11-fold but by 2 hours after infusion was significantly increased in only 1 of 6 subjects. Sodium excretion increased 3-to 8-fold, 3- to 6-fold, 0- to 2-fold (NS), and 3- to 11-fold, respectively, with proANFs 1-30, 31-67, 79-98, and ANF. Natriuretic effects of proANFs 1-30 and 31-67 were significantly prolonged (P<.001) compared with ANF. ProANFs 1-30, 31-67, 79-98, and ANF increased potassium excretion 2- to 3-fold, 0-fold, 3- to 4-fold, and 2-fold, respectively. High-performance gel permeation chromatography followed by the respective radioimmunoassays revealed that proANFs 1-30, 31-67, 79-98, and 68-98, as well as ANF circulate as distinct peptides. ConclusionsProANFs 1-30, 31-67, and 79-98, as well as ANF have significant blood pressure-lowering and diuretic properties. ProANFs 1-30 and 31-67 also have natriuretic properties in humans that are significantly (P<.001) prolonged compared with ANF. ProANF 79-98, although not possessing any natriuretic property, is the strongest stimulator of potassium excretion of the four atrial natriuretic peptides.

Decreased mortality of severe acute pancreatitis after proximal cytokine blockade

ObjectiveThis study determined the ability of interleukin-1 receptor antagonist (IL-1ra) to decrease the mortality of experimental acute pancreatitis. The response of the inflammatory cytokine cascade and its subsequent effects on pancreatic morphology were measured to determine the role of these peptides in mediating pancreatic injury. Summary Background DataPrevious studes have shown that proinflammatory cytokines are produced in large amounts during acute pancreatitis and that blockade at the level of the IL-1 receptor significantly decreases intrinsic pancreatic damage. The subsequent effect on survival is not known. MethodsA lethal form of acute hemorrhagic necrotizing pancreatitis was induced in young female mice by feeding a choline-deficient, ethionine supplemented (CDE) diet for 72 hours. For determination of mortality, the animals were divided into 3 groups of 45 animals each: control subjects received 100/μ L normal saline intraperitoneally every 6 hours for 5 days; IL-1ra early mice received recombinant interleukin-1 receptor antagonist 15 mg/kg intraperitoneally every 6 hours for 5 days beginning at time 0; IL-1ra late mice received IL-1 ra 15 mg/kg intraperitoneally every 6 hours for 3.5 days beginning 1.5 days after introduction of the CDE diet. A parallel experiment was conducted simultaneously with a minimum of 29 animals per group, which were sacrificed daily for comparisons of serum amylase, lipase, IL-1, IL-6, tumor necrosis factor-α, IL-1ra, pancreatic wet weight, and blind histopathologic grading. ResultsThe 10-day mortality in the untreated control group was 73%. Early and late IL-1ra administration resulted in decreases of mortality to 44% and 51%, respectively (both p < 0.001). Interleukin-1 antagonism also was associated with a significant attenuation in the rise in pancreatic wet weight and serum amylase and lipase in both early and late IL-1ra groups (all < 0.05). All control animals developed a rapid elevation of the inflammatory cytokines, with maximal levels reached on day 3. The IL-1ra-treated animals, however, demonstrated a blunted rise of these mediators (all p < 0.05). Blind histologic grading revealed an overall decrease in the severity of pancreatitis in those animals receiving the antagonist. ConclusionsEarly or late blockade of the cytokine cascade at the level of the IL-1 receptor significantly decreases the mortality of severe acute pancreatitis. The mechanism by which this is

Four peptides decrease the number of human pancreatic adenocarcinoma cells

Background  Long‐acting natriuretic peptide, vessel dilator, kaliuretic peptide and atrial natriuretic peptide are four peptide hormones synthesized by the same gene. Their main known biologic properties are sodium and water excretion and blood pressure lowering in both animals and humans.

Four peptide hormones decrease the number of human breast adenocarcinoma cells

Background  A family of six hormones, i.e. atrial natriuretic peptide, brain natriuretic peptide, C‐natriuretic peptide, long‐acting natriuretic peptide, vessel dilator, and kaliuretic peptides main known biologic properties are sodium and water excreting and blood pressure lowering.

Urodilatin and four cardiac hormones decrease human renal carcinoma cell numbers

Background Mortality from renal‐cell cancer remains a significant problem with an estimated 12 600 deaths in the United States in 2005 even with current treatment(s) of surgery, chemotherapy, radiation and immunotherapy. Four cardiac natriuretic peptides, that is, atrial natriuretic peptide, vessel dilator, long‐acting natriuretic peptide and kaliuretic peptide have significant anti‐cancer effects in breast, pancreatic, prostate and colon adenocarcinomas.

Four peptide hormones’ specific decrease (up to 97%) of human prostate carcinoma cells

Background  Mortality from prostate cancer remains a significant problem with current treatment(s), with an expected 30 350 deaths from prostate cancer in 2005. Long‐acting natriuretic peptide, vessel dilator, kaliuretic peptide and atrial natriuretic peptide have significant anticancer effects in breast and pancreatic adenocarcinomas. Whether these effects are specific and whether they have anticancer effects in prostate adenocarcinoma cells has not been determined.

Five cardiac hormones decrease the number of human small-cell lung cancer cells.

Background  Four peptide hormones of a family of six hormones, i.e. atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C‐natriuretic peptide (CNP), long acting natriuretic peptide (LANP), vessel dilator and kaliuretic peptide, significantly decrease the number of adenocarcinoma cells in culture. The present investigation was designed to determine whether these peptide hormones’ effects are specific to adenocarcinomas or whether they might decrease the number of cancer cells of a different type of cancer, i.e. small‐cell lung cancer.

Novel therapeutic approach for cancer using four cardiovascular hormones.

Background  The atrial natriuretic peptide (ANP) gene synthesizes four cardiovascular hormones, i.e. vessel dilator, long‐acting natriuretic peptide, kaliuretic peptide and ANP, which decrease the number of human pancreatic adenocarcinoma cells in culture by 65%, 47%, 37%, and 34%, respectively.

Directed antisense therapy confirms the role of protein kinase C–α in the tumorigenicity of pancreatic cancer

BACKGROUND The level of expression of the alpha isoform of protein kinase C (PKC-alpha) has been shown to correlate inversely with the pathologic differentiation of human pancreatic cancers. METHODS We stably transfected a moderately differentiated pancreatic cell line (HPAC) to overexpress PKC-alpha and examined the survival rates compared with parent HPAC according to an orthotopic model. Next we used a PKC-alpha antisense oligonucleotide specifically to down-regulate this isoform in vitro and examine the effect of treatment in vivo again according to the orthotopic model. RESULTS Animals implanted with the overexpressing cell line had a mortality rate almost twice that of those implanted with the parent cell line (P < .01). Treatment with antisense oligonucleotide in increasing concentrations down-regulated PKC-alpha mRNA by Northern blot analysis and reverse transcriptase-polymerase chain reaction. Animals treated with antisense oligonucleotide after orthotopic implantation of pancreatic cancer cells survived statistically longer than those treated with vehicle alone (P = .005). Treatment with a scrambled oligonucleotide also conferred a survival benefit compared with vehicle alone (P < .01). CONCLUSIONS Tumorigenicity of pancreatic cancer is related directly to PKC-alpha expression in vivo as demonstrated by decreased survival when overexpressed. PKC-alpha expression can be down-regulated directly (antisense) and indirectly (scrambled) in vitro, which subsequently confers a dramatic survival benefit in vivo.