Efficacy of daikenchuto after laparoscopic surgery for perforated appendicitis.

BACKGROUND: Although many recent studies have scientifically verified the efficacy of the traditional herbal medicine daikenchuto (DKT) for postoperative gastrointestinal function, its efficacy has not been established in children. We retrospectively evaluated the effect of DKT in pediatric patients with panperitonitis associated with perforated appendicitis (PaPA) who underwent laparoscopic appendectomy. METHODS: Among 34 children with PaPA who underwent laparoscopic appendectomy from May 2012 to May 2021, 19 received DKT (group D) and 12 did not (group C). We compared postoperative gastrointestinal function, complications, and improvement in the inflammatory response between the two groups. RESULTS: Of the evaluation parameters for postoperative gastrointestinal function, the mean ± standard deviation time to first flatus was significantly shorter in group D than in group C (1.21 ± 0.42 and 2.17 ± 0.94 days respectively; p = 0.0005). The time to ingestion of half a meal was also significantly shorter in group D than in group C (8.42 ± 3.69 and 12.50 ± 4.96 meal occasions respectively; p = 0.01). There was no significant difference in complication rates between the two groups. CONCLUSION: Daikenchuto rapidly and safely improved postoperative gastrointestinal symptoms in children with PaPA. To the best of our knowledge, this is the first study to evaluate the effect of DKT on postoperative symptoms in laparoscopic appendectomy and in children.

A case of biliary atresia with pancreaticobiliary maljunction.

BACKGROUND: The pathogenesis of biliary atresia (BA) is still unknown. There are several reports on the etiology of BA, including pancreaticobiliary maljunction (PBM). We experienced a case of Kasai type IIIa BA with PBM, in which we found elevation of pancreatic enzymes in the gallbladder. We evaluated whether PBM is related to the pathogenesis of BA based on our findings. CASE PRESENTATION: The patient was born at 40 weeks of gestation. His body weight at birth was 2850 g. At the age of 4 days, he had an acholic stool and was referred to our hospital. Abdominal ultrasonography showed that triangular cord sign was negative. The gallbladder was isolated with a diameter of 19 mm, and it contracted in response to oral feeding. His ultrasonographic findings were atypical for BA, but his jaundice did not improve. Therefore, we performed an operation at the age of 56 days. Intraoperative cholangiography showed a common bile duct and pancreatic duct and a common channel patent, while the common hepatic duct or intrahepatic duct was not visualized. Bile in the gallbladder contained colorless fluid, which showed elevated lipase level (34,100 IU/L). We performed Kasai portoenterostomy under the diagnosis of Kasai type IIIa BA with PBM. The patient's postoperative course was uneventful, and he was discharged on day 30 after the operation. Histopathological evaluation showed that the lumens of the common bile duct and cystic duct were patent. However, the common hepatic duct was closed, and only bile ductules with diameters of less than 50 µm were isolated. Infiltration of lymphocytes was detected in the porta hepatis. No apparent inflammation was observed around the cystic duct, which was constantly exposed to pancreatic juice because of reflux through PBM. CONCLUSIONS: Reflux of pancreatic juice through PBM might not be an etiological factor for BA, but might be associated with patency of the common and cystic bile ducts in Kasai type IIIa BA.

Different impacts of acylated and non-acylated long-acting insulin analogs on neural functions in vitro and in vivo.

AIMS: Centrally administered insulin improves cognitive functions in patients with Alzheimer's disease; however, it remains unknown whether long-acting insulin analogs exert more pronounced effects than insulin. In the present study, we directly compared the effects of insulin and its analogs on neural functions in vitro and in vivo. METHODS: Cultured rat cerebral cortical neurons were treated with insulin, insulin glargine U100 (Gla), insulin detemir (Det), or insulin degludec (Deg). Moreover, these drugs were intracerebroventricularly administered to mice. Their efficacies were evaluated by biochemical and behavioral analyses. RESULTS: In cultured neurons, insulin, Gla, and Det increased phosphorylation of Akt and enhanced gene expression of brain-derived neurotrophic factor to a similar extent, although Deg was less effective. The effects of Det and Deg, but not insulin and Gla were suppressed by addition of albumin. When the drug was centrally administered, the increasing effects of insulin on the Akt phosphorylation were comparable to those of Gla but greater than those of Det in hippocampus and cerebral cortex of diabetic db/db and non-diabetic db/m+ mice. Moreover, insulin and Gla enhanced memory functions in Y-maze test and suppressed depression-like behavior in forced swim test in normal mice to a similar extent, and these effects were more potent than those of Det. CONCLUSIONS: Insulin and Gla have greater impacts on central nervous system than insulin analogs with high albumin sensitivity, such as Det and Deg. These pharmacological profiles should be taken into account for developing an insulin-based therapy to treat Alzheimer's disease.

Evaluation of the intraoperative risk factors for esophageal anastomotic complications after primary repair of esophageal atresia with tracheoesophageal fistula.

PURPOSE: The aim of this study is to identify the risk factors for esophageal anastomotic stricture (EAS) and/or anastomotic leakage (EAL) after primary repair of esophageal atresia with tracheoesophageal fistula (EA/TEF) in infants. METHODS: A retrospective chart review of 52 patients with congenital EA/TEF between January 2000 and December 2015 was conducted. Univariate and multivariate analyses were performed to identify the risk factors for anastomotic complications. RESULTS: Twenty-four patients were excluded from the analysis because they had insufficient data, trisomy 18 syndrome, delayed anastomosis, or multi-staged operations; the remaining 28 were included. Twelve patients (42.9 %) had anastomotic complications. EAS occurred in 12 patients (42.9 %), and one of them had EAL (3.57 %). There was no correlation between anastomotic complications and birth weight, gestational weeks, sex, the presence of an associated anomaly, age at the time of repair, gap between the upper pouch and lower pouch of the esophagus, number of sutures, blood loss, and gastroesophageal reflux. Anastomosis under tension and tracheomalacia were identified as risk factors for anastomotic complications (odds ratio 15, 95 % confidence interval (CI) 1.53-390.0 and odds ratio 8, 95 % CI 1.33-71.2, respectively). CONCLUSION: Surgeons should carefully perform anastomosis under less tension to prevent anastomotic complications in the primary repair of EA/TEF.

Surgical intervention strategies for congenital tracheal stenosis associated with a tracheal bronchus based on the location of stenosis.

PURPOSE: The aim of this study was to determine the appropriate surgical intervention strategies for congenital tracheal stenosis (CTS) associated with a tracheal bronchus based on the location of stenosis. METHODS: The medical records of 13 pediatric patients with CTS associated with a tracheal bronchus at a single institution between January 2006 and December 2015 were retrospectively reviewed. RESULTS: Type 1: tracheal stenosis above the right upper lobe bronchus (RULB) (n = 1). One patient underwent slide tracheoplasty and was successfully extubated. Type 2: tracheal stenosis below the RULB (n = 7). Tracheal end-to-end anastomosis was performed before 2014, and one patient failed to extubate. Posterior-anterior slide tracheoplasty was performed since 2014, and all three patients were successfully extubated. Type 3: tracheal stenosis above the RULB to the carina (n = 5). One patient underwent posterior-anterior slide tracheoplasty and was successfully extubated. Two patients with left-right slide tracheoplasty and another two patients with tracheal end-to-end anastomosis for the stenosis below the RULB could not be extubated. CONCLUSION: Tracheal end-to-end anastomosis or slide tracheoplasty can be selected for tracheal stenosis above the RULB according to the length of stenosis. Posterior-anterior slide tracheoplasty appears feasible for tracheal stenosis below the RULB or above the RULB to the carina.

Establishment of the MethyLight Assay for Assessing Aging, Cigarette Smoking, and Alcohol Consumption.

The environmental factors such as aging, smoking, and alcohol consumption have been reported to influence DNA methylation (DNAm). However, the versatility of DNAm measurement by DNAm array systems is low in clinical use. Thus, we developed the MethyLight assay as a simple method to measure DNAm. In the present study, we isolated peripheral blood DNA from 33 healthy volunteers and selected cg25809905, cg02228185, and cg17861230 as aging, cg23576855 as smoking, and cg02583484 as alcohol consumption biomarkers. The predicted age by methylation rates of cg25809905 and cg17861230 significantly correlated with chronological age. In immortalized B-cells, DNAm rates of two sites showed a younger status than the chronological age of donor. On the other hand, the predicted age of the patients with myocardial infarction (MI) was not accelerated. The methylation rate of cg23576855 was able to discriminate the groups based on the smoking status. The DNAm rate of cg02583484 was reduced in subjects with habitual alcohol consumption compared to that of subjects without habitual alcohol consumption. In conclusion, our MethyLight assay system reconfirms that aging, smoking, and alcohol consumption influenced DNAm in peripheral blood in the Japanese. This MethyLight system will facilitate DNAm measurement in epidemiological and clinical studies.

Severe acquired subglottic stenosis in children: analysis of clinical features and surgical outcomes based on the range of stenosis.

PURPOSE: The present study analyzed the clinical features and surgical outcomes of laryngotracheal reconstruction (LTR) in pediatric patients with severe acquired subglottic stenosis (SGS) based on the range of stenosis. The aim was to clarify the indications for LTR in severe acquired SGS. METHODS: The medical records of 33 pediatric patients with severe acquired SGS (Myer-Cotton grade III or IV) at our institution between January 1994 and December 2013 were retrospectively reviewed. RESULTS: Nine patients had stenosis localized at the subglottis (localized SGS), and twenty-four patients had stenosis extending to the glottis or supraglottis from the subglottis (extended SGS). 66.7 % (6/9) of localized SGS patients were intubated after infancy, and 95.8 % (22/23) of extended SGS patients were intubated in the neonatal period. The duration of intubation was significantly shorter with localized than with extended SGS. Sixteen patients underwent LTR. The operation-specific decannulation rate was 80.0 % (4/5) in the localized SGS group and 14.3 % (1/7) in the extended SGS group. CONCLUSION: The range of stenosis was affected by the period and duration of endotracheal intubation. Surgical outcomes of LTR tended to differ between localized SGS and extended SGS. LTR can be effective for localized SGS.

Thoracoscopic repair of a large neonatal congenital diaphragmatic hernia using Gerota's fascia.

A large congenital diaphragmatic hernia needing patch repair has a high risk of recurrence. Thus, managing these large congenital diaphragmatic hernias under thoracoscopy has become a problem. Here, a large congenital diaphragmatic hernia that was repaired using Gerota's fascia under thoracoscopy is reported. In the present case, it was impossible to close the hernia directly under thoracoscopy because the hernia was too large. Gerota's fascia was raised up by the left kidney and used for the repair. The left colon adhering to Gerota's fascia was mobilized, and a large space was made under thoracoscopy. Gerota's fascia was fixed to the diaphragmatic defect. The patient's postoperative course was good, and there was no recurrence. This technique could be one option for repairing a large hernia under thoracoscopy.

Pretransplant replacement of donor liver grafts with recipient Kupffer cells attenuates liver graft rejection in rats.

BACKGROUND AND AIM: Rejection of liver grafts is a difficult issue that has not been resolved. Preoperative replacement of liver cells in the graft with cells from the intended recipient may attenuate rejection. We investigated whether preoperative transplant of recipient bone marrow cells (BMCs) to the donor replaced liver allograft cells and attenuated rejection. METHODS: We used a rat model of allogeneic liver transplant (LT) from Dark Agouti (DA) to Lewis (LEW) rats. In BMC group, DA rats received BMC transplants from LacZ-transgenic LEW rats at 1 week before LT. In the control group, DA rats received no preoperative treatment. We evaluated graft damage at 7 days after LT and the survival of the recipient rats. RESULTS: Rats in the BMC group experienced prolonged survival that was abrogated by the administration of gadolinium chloride to donors at 24 h before LT. Serum concentrations of total bilirubin and hyaluronic acid on day 7 were significantly lower in the BMC group, and histopathological analyses revealed that rejection of the liver graft was attenuated. X-gal staining and immunohistostaining of the liver graft revealed that BMCs engrafted in the sinusoidal space differentiated into Kupffer cells. CONCLUSIONS: Preoperative transplant of recipient BMCs to LT donors replaced donor Kupffer cells and attenuated post-LT rejection, indicating that this strategy may increase the success of LT.

Whey-hydrolyzed peptide-enriched immunomodulating diet prevents progression of liver cirrhosis in rats.

OBJECTIVE: Liver fibrosis and subsequent cirrhosis is a major cause of death worldwide, but few effective antifibrotic therapies are reported. Whey-hydrolyzed peptide (WHP), a major peptide component of bovine milk, exerts anti-inflammatory effects in experimental models. A WHP-enriched diet is widely used for immunomodulating diets (IMD) in clinical fields. However, the effects of WHP on liver fibrosis remain unknown. The aim of this study was to investigate the antifibrotic effects of WHP in a rat cirrhosis model. METHODS: Progressive liver fibrosis was induced by repeated intraperitoneal administration of dimethylnitrosamine (DMN) for 3 wk. Rats were fed either a WHP-enriched IMD (WHP group) or a control enteral diet (control group). The degree of liver fibrosis was compared between groups. Hepatocyte-protective effects were examined using hepatocytes isolated from rats fed a WHP diet. Reactive oxygen species and glutathione in liver tissue were investigated in the DMN cirrhosis model. RESULTS: Macroscopic and microscopic progression of liver fibrosis was remarkably suppressed in the WHP group. Elevated serum levels of liver enzymes and hyaluronic acid, and liver tissue hydroxyproline content were significantly attenuated in the WHP group. Necrotic hepatocyte rates with DMN challenge, isolated from rats fed a WHP-enriched IMD, were significantly lower. In the DMN cirrhosis model, reactive oxygen species were significantly lower, and glutathione was significantly higher in the WHP group's whole liver tissue. CONCLUSION: A WHP-enriched IMD effectively prevented progression of DMN-induced liver fibrosis in rats via a direct hepatocyte-protective effect and an antioxidant effect through glutathione synthesis.

A novel biomarker for acute kidney injury using TaqMan-based unmethylated DNA-specific polymerase chain reaction.

There has been increasing interest in the use of circulating DNA as biomarkers for various tissue injuries, cancers, and fetal conditions. DNA methylation is a well-characterized mechanism underlying the epigenetic regulation of gene expression, and many diagnostic tests based on DNA methylation patterns have been developed. We developed a novel TaqMan-based assay for the detection of acute kidney injury using a hypomethylated promoter region of Slc22a12, a urate transporter specifically expressed in proximal tubular cells. Bisulfite sequencing analysis confirmed that the CpG islands in the promoter region of mouse Slc22a12 were preferentially hypomethylated in the kidney cortex. TaqMan minor groove binder (MGB) probes reliably discriminated the DNA fragments corresponding to the unmethylated and methylated promoter regions of Slc22a12. Plasma levels of unmethylated DNA corresponding to the Slc22a12 promoter region were undetectable at baseline and were significantly elevated after acute kidney cortex necrosis. This study showed the usefulness of the TaqMan system in discriminating methylated and unmethylated DNA fragments, and the similar strategy can be applied for establishing biomarkers for various cellular injuries or pathological conditions.

How to successfully resect 70 % of the liver in pigs to model an extended hepatectomy with an insufficient remnant or liver transplantation with a small-for-size graft.

An insufficient remnant in extended hepatectomy and small-for-size graft in liver transplantation are critical matters in the field of liver surgery, and reliable and reproducible animal models that can provide clinically relevant and reliable data are needed. We herein describe our detailed surgical procedures for performing 70 % hepatectomy in pigs, and discuss the critical anatomical features, key techniques and pitfalls based on our experience. The porcine liver is divided into four lobes. The right lateral lobe (RLL) accounts for 30 % of the liver volume. Important points, such as selective temporal clamping of the arterial branch, confirmation of a related demarcation line, a two-step process to skeletonize Glisson's capsules during liver resection and selective ligation of the portal venous branch to the right medial lobe without inducing any subtle injuries to Glisson's capsules from the RLL to common bile duct, are discussed.

Impact of preoperative uncontrollable hepatic hydrothorax and massive ascites in adult liver transplantation.

PURPOSE: Uncontrollable hepatic hydrothorax and massive ascites (H&MA) requiring preoperative drainage are sometimes encountered in liver transplantation (LT). We retrospectively analyzed the characteristics of such patients and the impact of H&MA on the postoperative course. METHODS: We evaluated 237 adult patients who underwent LT in our institute between April 2006 and October 2010. RESULTS: Recipients with uncontrollable H&MA (group HA: n = 36) had more intraoperative bleeding, higher Child-Pugh scores, lower serum albumin concentrations and higher blood urea nitrogen concentrations than those without uncontrollable H&MA (group C: n = 201). They were also more likely to have preoperative hepatorenal syndrome and infections. The incidence of postoperative bacteremia was higher (55.6 vs. 46.7%, P = 0.008) and the 1- and 3-year survival rates were lower (1 year: 58.9 vs. 82.9%; 3 years: 58.9 vs. 77.7%; P = 0.003) in group HA than in group C. The multivariate proportional regression analyses revealed that uncontrollable H&MA and the Child-Pugh score were independent risk factors for the postoperative prognosis. CONCLUSIONS: Postoperative infection control may be an important means of improving the outcome for patients with uncontrollable H&MA undergoing LT, and clinicians should strive to perform surgery before H&MA becomes uncontrollable.

Renoprotective mechanisms of pirfenidone in hypertension-induced renal injury: through anti-fibrotic and anti-oxidative stress pathways.

Pirfenidone (PFD) is a novel anti-fibrotic agent that targets TGFß. However, the mechanisms underlying its renoprotective properties in hypertension-induced renal injury are poorly understood. We investigated the renoprotective properties of PFD and clarified its renoprotective mechanisms in a rat hypertension-induced renal injury model. Dahl salt-sensitive rats were fed a high-salt diet with or without 1% PFD for 6 weeks. During the administration period, we examined the effects of PFD on blood pressure and renal function. After the administration, the protein levels of renal TGFß, Smad2/3, TNFα, MMP9, TIMP1, and catalase were examined. In addition, total serum antioxidant activity was measured. Compared to untreated rats, PFD treatment significantly attenuated blood pressure and proteinuria. Histological study showed that PFD treatment improved renal fibrosis. PFD may exert its anti-fibrotic effects via the downregulation of TGFß-Smad2/3 signaling, improvement of MMP9/TIMP1 balance, and suppression of fibroblast proliferation. PFD treatment also increased catalase expression and total serum antioxidant activity. In contrast, PFD treatment did not affect the expression of TNFα protein, macrophage or T-cell infiltration, or plasma interleukin 1ß levels. PFD prevents renal injury via its anti-fibrotic and anti-oxidative stress mechanisms. Clarifying the renoprotective mechanisms of PFD will help improve treatment for chronic renal diseases.

Effect of cold ischemia/reperfusion injury and/or shear stress with portal hypertension on the expression of matrix metalloproteinase-9.

BACKGROUND: Matrix metalloproteinase (MMP)-9 plays an important role in liver regeneration after liver surgery. MMP-9 behavior is complicated in cold ischemia/warm reperfusion injury (CIWRI) and/or shear stress with portal hypertension. Small-for-size grafts (SFSGs) are also an issue. MATERIALS AND METHODS: We used a rat model to examine MMP-9 expression 6 h after laparotomy, a temporal clamp (Pringle maneuver), orthotopic liver transplantation (OLT) with a whole-liver graft (100% OLT), partial hepatectomy without the Pringle maneuver (60% hepatectomy) and split orthotopic liver transplantation (SOLT) with a SFSG (40% SOLT) were investigated. Four liver samples were collected in each group. RESULTS: The normalized ratio of MMP-9 was not significantly different with a temporal clamp (P = 0.1963), 100% OLT (P = 0.1781) and 60% hepatectomy (P = 0.2367), but it was significantly higher with 40% SOLT compared to that with laparotomy (P = 0.0159). CONCLUSION: Forty percent SOLT is accompanied by not only CIWRI but also shear stress. This fatal damage results in increased MMP-9 expression.

Development of dry powder inhalation system of novel vasoactive intestinal peptide (VIP) analogue for pulmonary administration.

Vasoactive intestinal peptide (VIP) exerts a relaxing action on tracheal smooth muscle which is mediated through interaction with VIP receptors. The deficiency of VIP in the airways has been implicated in the pathogenesis of asthma. Thus, the administration of VIP may be useful for the therapy of pulmonary diseases. However, the therapeutic application of VIP is largely limited by its rapid degradation in addition to the systemic adverse effects due to the wide distribution of VIP receptors. To overcome these problems, we succeeded to synthesize a novel VIP derivative of VIP, [R15, 20, 21, L17]-VIP-GRR (IK312532), and to prepare its dry powder for the topical administration to the lung. The physicochemical properties of dry powder were evaluated by laser diffraction and cascade impactor. The laser diffraction analysis indicated that the carrier and fine particles had median diameter of 65.6 and 4.5 microm, respectively, and the air flow at the pressure of 0.15 MPa or higher resulted in the high dispersion and significant separation of fine particle containing peptide from the carrier molecule. The cascade impactor analysis clearly showed the high emission of dry powder from capsule and the deposition of peptide on stages 3 of the cascade impactor. The intratracheal administration of dry powder inhaler (DPI) of VIP or IK312532 brought about a significant decrease of maximal number of binding sites (Bmax) for [125I]VIP in anterior and posterior lobes of rat right lung, suggesting a significant occupancy of lung VIP receptors. This effect by IK312532-DPI compared with VIP-DPI lasted for a longer period. Thus, IK312532-DPI may be a pharmacologically useful drug delivery system for the VIP therapy of pulmonary diseases such as asthma.

Pharmacological effects and lung-binding characteristics of a novel VIP analogue, [R15, 20, 21, L17]-VIP-GRR (IK312532).

A novel VIP derivative, [R15, 20, 21, L17]-VIP-GRR (IK312532), relaxed potently the carbachol-induced contraction of guinea-pig isolated trachea with longer duration than that induced by VIP. IK312532 competed with [125I]VIP for the binding sites in the rat lung in a concentration-dependent manner. There was considerable decrease in specific [125I]VIP binding in each lobe of right and left lung 0.5 h after the intratracheal administration of IK312532 (50 microg/rat) as dry powder inhaler (DPI). Rosenthal analysis revealed that the administration of IK312532 (50 and 100 microg/rat)-DPI brought about a significant decrease of maximal number of binding sites (Bmax) for specific [125I]VIP binding in anterior and posterior lobes of rat right lung, suggesting a significant occupancy of lung VIP receptors. This effect by IK312532 in the posterior lobe of the right lung was dose-dependent and lasted until at least 2 h after the intratracheal administration. Furthermore, the antigen-evoked infiltration of granulocytes in the rat bronchiolar mucosa was markedly suppressed by the intratracheal administration of IK312532 (50 microg/rat)-DPI. In conclusion, the present study has shown that IK312532 exhibits long-lasting relaxation of tracheal smooth muscles and that the intratracheal administration of this peptide exerts a significant occupancy of lung VIP receptors as well as a suppression of the antigen-evoked infiltration of granulocytes in the bronchiolar mucosa. Thus, the formulation of IK312532 as DPI may be a pharmacologically useful drug delivery system for the therapy of pulmonary diseases such as asthma.

Long-acting analogue of vasoactive intestinal peptide, [R15, 20, 21, L17]-VIP-GRR (IK312532), protects rat alveolar L2 cells from the cytotoxicity of cigarette smoke.

Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) act as neurotransmitters in numerous biological responses. We previously reported that the replacement of Lys by Arg, and Met by Leu in VIP (IK312532; [Arg15, 20, 21, Leu17]-VIP) resulted in a significant improvement in metabolic stability and biological activity. In the present study, we investigated the effect of VIP and its related peptides including long-acting VIP derivative (IK312532) and PACAP27 on the cytotoxicity of cigarette smoke extract (CSE), a causative factor of chronic obstructive pulmonary disease (COPD), in rat alveolar L2 cells. RT-PCR displayed the dominant expression of mRNA for the VIP-specific VPAC2 receptor in L2 cells, and VIP and the related peptides showed the specific binding activity and potent stimulation of adenylate cyclase. CSE at a concentration of 0.1% or higher induced significant apoptotic death of L2 cells. Interestingly, the addition of neuropeptides at a concentration of 10(-11) M or higher in L2 cells with CSE (0.25%) resulted in significant attenuation of cell death with the deactivation of CSE-evoked caspase-3 activity. IK312532 was much stable against the enzymatic digestion compared to VIP, and the protective effect of IK312532 was 1.6-fold higher than that of VIP. Taken together with our previous report showing that IK312532 has long-acting relaxant activity in the lung, IK312532 may be a potential candidate for drug treatment of asthma and COPD.

Vasoactive intestinal peptide and pituitary adenylate cyclase-activating polypeptide attenuate the cigarette smoke extract-induced apoptotic death of rat alveolar L2 cells.

Chronic obstructive pulmonary disease is a major clinical disorder usually associated with cigarette smoking. A central feature of chronic obstructive pulmonary disease is inflammation coexisting with an abnormal protease/antiprotease balance, leading to apoptosis and elastolysis. In an in vitro study of rat lung alveolar L2 cells, cigarette smoke extract (CSE) induced apoptotic cell death. Exposure of L2 cells to CSE at a concentration of 0.25% resulted in a 50% increase of caspase-3 and matrix metalloproteinase (MMP) activities. Specific inhibitors for caspases and MMPs attenuated the cytotoxicity of CSE. RT-PCR amplification identified VPAC2 receptors in L2 cells. A radioligand-binding assay with (125)I-labeled vasoactive intestinal peptide (VIP) found high affinity and saturable (125)I-labeled VIP-binding sites in L2 cells. VIP and pituitary adenylate cyclase-activating polypeptide (PACAP27) were approximately equipotent for both VIP receptor binding and stimulation of cAMP production in L2 cells. Both neuropeptides, at concentrations higher than 10(-13) m, produced a concentration-dependent inhibition of CSE-induced cell death in L2 cells. VIP, at 10(-7) m, reduced CSE-stimulated MMP activity and caspase-3 activation. The present study has shown that VIP and PACAP27 significantly attenuate the cytotoxicity of CSE through the activation of VPAC2 receptor, and the protective effect of VIP may partly be the result of a reduction in the CSE-induced stimulation of MMPs and caspases.

The neuropeptide PACAP attenuates beta-amyloid (1-42)-induced toxicity in PC12 cells.

Pituitary adenylate cyclase activating polypeptide (PACAP) modulates neurotransmission in the central and peripheral nervous systems. In vitro and in vivo studies have shown the protective effects of PACAP against neuronal damage induced by ischemia and agonists of NMDA-type glutamate receptors. Here, we demonstrated that PACAP also protected against neuronal toxicity induced by beta-amyloid (Abeta) peptide, aggregation of which is a causative factor for Alzheimer's disease. PACAP (10(-9)M) rescued 80% of decreased cell viability and 50% of elevated caspase-3 activity that resulted from exposure of PC12 cells to Abeta. PACAP was at least 10(4)-fold more effective than other neuropeptides including vasoactive intestinal peptide (VIP) and humanin, which correlated with the level of cAMP accumulation. Thus, our results suggested that PACAP attenuates Abeta-induced cell death in PC12 cells through an increase in cAMP and that caspase-3 deactivation by PACAP is involved in the signaling pathway for this neuroprotection.