Engineering a Model Cell for Rational Tuning of GPCR Signaling.

G protein-coupled receptor (GPCR) signaling is the primary method eukaryotes use to respond to specific cues in their environment. However, the relationship between stimulus and response for each GPCR is difficult to predict due to diversity in natural signal transduction architecture and expression. Using genome engineering in yeast, we constructed an insulated, modular GPCR signal transduction system to study how the response to stimuli can be predictably tuned using synthetic tools. We delineated the contributions of a minimal set of key components via computational and experimental refactoring, identifying simple design principles for rationally tuning the dose response. Using five different GPCRs, we demonstrate how this enables cells and consortia to be engineered to respond to desired concentrations of peptides, metabolites, and hormones relevant to human health. This work enables rational tuning of cell sensing while providing a framework to guide reprogramming of GPCR-based signaling in other systems.

Cell-penetrating peptide-linked polymers as carriers for mucosal vaccine delivery.

We evaluated the potential of poly(N-vinylacetamide-co-acrylic acid) modified with d-octaarginine, which is a typical cell-penetrating peptide, as a carrier for mucosal vaccine delivery. Mice were nasally inoculated four times every seventh day with PBS containing ovalbumin with or without the d-octaarginine-linked polymer. The polymer enhanced the production of ovalbumin-specific immunoglobulin G (IgG) and secreted immunoglobulin A (IgA) in the serum and the nasal cavity, respectively. Ovalbumin internalized into nasal epithelial cells appeared to stimulate IgA production. Ovalbumin transferred to systemic circulation possibly enhanced IgG production. An equivalent dose of the cholera toxin B subunit (CTB), which was used as a positive control, was superior to the polymer in enhancing antibody production; however, dose escalation of the polymer overcame this disadvantage. A similar immunization profile was also observed when ovalbumin was replaced with influenza virus HA vaccines. The polymer induced a vaccine-specific immune response identical to that induced by CTB, irrespective of the antibody type, when its dose was 10 times that of CTB. Our cell-penetrating peptide-linked polymer is a potential candidate for antigen carriers that induce humoral immunity on the mucosal surface and in systemic circulation when nasally coadministered with antigens.

Camptothecin disrupts androgen receptor signaling and suppresses prostate cancer cell growth.

The androgen receptor (AR) is the main therapeutic target for treatment of metastatic prostate cancers. The present study demonstrates that the topoisomerase I inhibitor camptothecin selectively inhibits androgen-responsive growth of prostate cancer cells. Camptothecin strikingly inhibited mutated and wild-type AR protein expression in LNCaP and PC-3/AR cells. This inhibition coincided with decreased androgen-mediated AR phosphorylation at Ser(81) and reduced androgen-mediated AR transcriptional activity in a dose-dependent manner. Additionally, camptothecin disrupted the association between AR and heat shock protein 90 and impeded binding of the synthetic androgen [3H]R1881 to AR in LNCaP cells. Camptothecin also blocked androgen-induced AR nuclear translocation, leading to downregulation of the AR target gene PSA. In addition to decreasing the intracellular and secreted prostate-specific antigen (PSA) levels, camptothecin markedly inhibited androgen-stimulated PSA promoter activity. Collectively, our data reveal that camptothecin not only serves as a traditional genotoxic agent but, by virtue of its ability to target and disrupt AR, may also be a novel candidate for the treatment of prostate cancer.

Surgical venous thrombectomy for Japanese patients with acute deep vein thrombosis: a review of 5 years' experience.

OBJECTIVE: Deep vein thrombosis (DVT) is a major risk factor for pulmonary thromboembolism (PTE). We carefully selected patients for surgical thrombectomy to treat acute-phase thrombosis and obtained favorable results. METHODS: Over the past 5 years, we have performed surgical thrombectomy via a minimum femoral skin incision in 11 patients. Surgery was considered for patients with persistent phlegmasia cerulea dolens, despite thrombolytic therapy. All of our patients underwent surgery within 14 days of the onset of symptoms. During the operation, the patients were kept in the supine anti-Trendelenburg position to prevent PTE, and general anesthesia was maintained with positive-pressure mechanical ventilation. Blood flow to the inferior vena cava was occluded with a blocking catheter, and thrombectomy was performed with a thrombectomy catheter inserted parallel to the blocking catheter. A cell separator device was used effectively for autologous blood transfusion. To prevent reocclusion and promote collateral perfusion, we constructed an arteriovenous fistula for an iliac venous spur. RESULTS: There were no major postoperative complications, such as PTE or peritoneal bleeding, and no cases of postthrombotic syndrome after an average 38.4 months of follow-up. CONCLUSION: This surgical technique for venous thrombectomy is minimally invasive and safe for Japanese patients; surgical thrombectomy should be considered a treatment option for DVT in Japan.

Different patterns of 5alpha-reductase expression, cellular distribution, and testosterone metabolism in human follicular dermal papilla cells.

Androgens regulate hair growth, and 5alpha-reductase (5alphaR) plays a pivotal role in the action of androgens on target organs. To clarify the molecular mechanisms responsible for controlling hair growth, the present study presents evidence that the human follicular dermal papilla cells (DPCs) from either beard (bDPCs) or scalp hair (sDPCs) possess endogenous 5alphaR activity. Real-time RT-PCR revealed that the highest level of 5alphaR1 mRNA was found in bDPCs, followed by sDPCs, and a low but detectable level of 5alphaR1 mRNA was observed in fibroblasts. Minimally detectable levels of 5alphaR2 mRNA were found in all three cell types. A weak band at 26kDa corresponding to the human 5alphaR1 protein was detected by Western blot in both DPCs, but not in fibroblasts. Immuonofluorescence analysis confirmed that 5alphaR1 was localized to the cytoplasm rather than in the nuclei in both DPCs Furthermore, a 5alphaR assay using [(14)C]testosterone labeling in intact cells revealed that testosterone was transformed primarily into androstenedione, and in small amounts, into DHT. Our results demonstrate that the 5alphaR activities of either bDPCs or sDPCs are stronger than that of dermal fibroblasts, despite the fact that the major steroidogenic activity is attributed to 17beta-HSD rather than 5alphaR among the three cell types. The 5alphaR1 inhibitor MK386 exhibited a more potent inhibitory effect on 5alphaR activity than finasteride (5alphaR2 inhibitor) in bDPCs.

Percutaneous penetration of felbinac after application of transdermal patches: relationship with pharmacological effects in rats.

We have evaluated the percutaneous penetration of felbinac following application of topical patches using a microdialysis technique, and have examined correlations with pharmacological effects. A linear microdialysis probe with a 20-mm dialysis fibre was inserted into the skin of anaesthetized rats. Probe perfusion was started at 2.0 microL min(-1) with physiological saline and after a 60-min baseline sampling of dialysate, 0.1 mL croton oil was applied to the skin surface at a concentration of 8%, v/v. A felbinac patch was then applied to the same point 60 min thereafter and dialysate was sampled at 60-min intervals up to 300 min after patch application, for determination of concentrations of felbinac and prostaglandin (PG) E2. Analgesic effects of felbinac patches in an iodoacetateinduced osteoarthritis model and an incisional pain model were evaluated using the weight bearing method. After application of patches, felbinac penetration into the skin was rapid, maximum concentrations in the dialysates with 0.07, 0.5 and 3.5% w/w felbinac patches being 0.046+/-0.02, 0.104+/-0.06 and 0.244+/-0.2 microg mL(-1), respectively. Dermal administration of croton oil caused an increment in PGE2 levels, which was significantly decreased by 0.5 and 3.5% felbinac patches 2-5 h after application. In pharmacological studies, 3.5% felbinac patches suppressed pain-associated behaviour induced by iodoacetate injection and plantar incision. These results suggested that the transdermal patch containing 3.5% felbinac may become a useful formulation.

Automated analysis of fluvoxamine in rat plasma using a column-switching system and ion-pair high-performance liquid chromatography.

We have established a robust, fully automated analytical method for the analysis of fluvoxamine in rat plasma using a column-switching ion-pair high-performance chromatography system. The plasma sample was injected onto a precolumn packed with Shim-pack MAYI-ODS (50 microm), where the drug was automatically purified and enriched by on-line solid-phase extraction. After elution of the plasma proteins, the analyte was back-flushed from the precolumn and then separated isocratically on a reversed-phase C18 column (L-column ODS) with a mobile phase (acetonitrile-0.1% phosphoric acid, 36:64, v/v) containing 2 mM sodium 1-octanesulfonate. The analyte was monitored by a UV detector at a wavelength of 254 nm. The calibration line for fluvoxamine showed good linearity in the range of 5-5000 ng/mL (r > 0.999) with the limit of quantification of 5 ng/mL (RSD = 6.51%). Accuracy ranged from -2.94 to 4.82%, and the within- and between-day precision of the assay was better than 8% across the calibration range. The analytical sensitivity and accuracy of this assay is suitable for characterization of the pharmacokinetics of orally-administered fluvoxamine in rats.

Molecular response to phototoxic stress of UVB-irradiated ketoprofen through arresting cell cycle in G2/M phase and inducing apoptosis.

The phototoxicity of ketoprofen (KP), a non-steroidal anti-inflammatory drug, has recently attracted considerable attention, because it is photolabile and undergoes degradation when irradiated by sunlight to induce various skin diseases. The present study shows that combination of UVB irradiation with KP induced the cytotoxicity and suppressed DNA synthesis in HaCaT cells in a concentration-dependent manner. UVB-irradiated KP inhibited the cell growth and induced G2/M cell cycle arrest by modulating the levels of cdc2, cyclin B1, Chk1, Tyr15-phosphorylated cdc2 and p21. It also provoked a striking accumulation of cyclin B1-cdc2-p21 complexes, concomitantly with an increase in the levels of Tyr15-phosphorylated cdc2 and p21 protein. The presence of KP accentuated the apoptotic response to UVB radiation in HaCaT cells as evidenced by DAPI staining. The apoptotic process was associated with activation of caspase-9, caspase-3 and cleavage of PARP, and this activation could be prevented by a specific caspase-3 inhibitor. Taken together, our results suggest that KP-photoinduced apoptosis may be a useful approach to reduce or prevent skin carcinogenesis.

Separate development of nitric oxide synthase- and vasoactive intestinal polypeptide-immunoreactive nerves arising from the vertebral artery in the rat.

Development of nitric oxide synthase (NOS)-and vasoactive intestinal polypeptide (VIP)-immunoreactive (-IR) nerves supplying the basilar and vertebral arteries (BA and VA) was investigated in White Wistar rats, using double immunohistochemistry. NOS-IR and VIP-IR nerves via the anterior circulation (AC), which mostly expressed NO(+)/VIP(+), extended to the BA during the second postnatal week, and usually reached as far as the rostral two third of the BA on PND 20. NOS-IR nerves were completely lack in the cBA and the VA on PND10, and often absent from these arterial regions even at PND 20. Nevertheless, a small number of VIP(+)/NOS(-) nerves were localized in the walls from the caudal BA (cBA) to the VA on PND 5. On PND 20, they frequently met with the descending NOS-IR and VIP-IR nerves via the AC around the lower portion of the middle BA. Fiber bundles containing NOS(+)/VIP(+) axons were first visualized on the caudal VA at PND 30 and observed frequently at PND 80, with a distinct increase in number of NOS-IR and VIP-IR nerves supplying the cBA and the VA. Thus, NOS-IR nerves coming from the VA develop through its own characteristic sequence that lags markedly behind the time of appearance for VIP-IR nerves from the same vascular route and for NOS-IR and VIP-IR nerves via the AC.

Phototoxicity study of a ketoprofen poultice in guinea pigs.

Ketoprofen has been reported to have such side effects as photosensitive dermatitis in humans (The Ministry of Health, Labour and Welfare, 2001). In the present study, as part of a safety evaluation of Miltax, an application drug containing ketoprofen, phototoxicity of Miltax was examined in guinea pigs. In the present skin phototoxicity study, Miltax was applied for 12 hr. Ultraviolet (UV) rays were irradiated to examine whether or not Miltax elicited skin reaction. Two kinds of UV-A plus UV-B dual irradiation and UV-A single irradiation were used for the elicitation. With UV-A plus UV-B dual irradiation on the Miltax application site, no skin reaction was observed at UV irradiation side in any animals, in contrast to the case of the positive control article, 8-methoxypsoralen (8-MOP). Similar results were obtained with UV-A single irradiation. From these results, Miltax that contained ketoprofen did not show any skin phototoxicity in the guinea pig.

Modification of the radial procedure in a patient with partial atrioventricular septal defect.

We successfully cured atrial fibrillation while preserving internodal conduction in a patient with a partial atrioventricular septal defect. Because the anterior and middle internodal tracts are interrupted by the defect, the lower right atrial incision of either the maze or the radial procedure may interrupt the remaining posterior tract, resulting in internodal conduction block. We deleted the posterior septal incision from the radial procedure and replaced it with a right-side left atriotomy. The patient resumed normal sinus rhythm with significant contraction of the right and left atria. The preserved internodal pathway through the posterior interatrial septum was confirmed by electrophysiologic study.

Comparison of poultice-type and tape-type patches containing ketoprofen on human skin irritation.

Although the patch test for visual skin observation is widely used clinically, it does not allow the mechanisms of side effects to be assessed. In this study, we examined poultice-type KP801 and tape-type KP-T patches containing ketoprofen. The parameters to measure side effects on skin were peeling intensity, amount of stripped stratum corneum, skin moisture and redness of skin color under various mechanical conditions. Since the amount of stripped stratum corneum with the tape-type KP-T patch was higher than with the poultice-type KP801 patch, the bio-adhesive strength of the latter was concluded to be lower. A clear relationship exists between the amount of stripped stratum corneum and skin moisture after tape-type patch removal, but this was not found with the poultice-type patch because of its hydration effects. Peeling intensity, one parameter to predict pain at the time of patch removal, was higher with the KP-T. As for mechanical conditions, when the patch is removed, it is important to remove it as slowly as possible and horizontally, and to avoid any rise in skin temperature. Finally, when a patch is applied to a region with little skin moisture, the amount of stripped stratum corneum may increase accordingly.

Optimal time of surgical treatment for Kawasaki coronary artery disease.

BACKGROUND: The major complication of Kawasaki coronary disease is myocardial infarction caused by thrombus formation inside the aneurysm or by organic obstructive lesion following the regression of aneurysm, while the indications for surgical therapy remain controversial. We have adopted coronary artery bypass grafting (CABG) even in young children for giant coronary aneurysms (more than 8 mm diameter) with or without a stenotic region when myocardial ischemia is detected. We hypothesized that a shorter time-period from diagnosis of acute Kawasaki disease (KD) to CABG would lead to better postoperative results. To elucidate the validity of our strategy, we evaluated preoperative patient characteristics and long-term outcome. METHODS: Twenty-one patients (mean age: 12.0 years old) with Kawasaki coronary disease had undergone CABG during the last 12 years. The mean age at the time of acute KD was 2.7 years and the mean time range from diagnosis of acute KD to CABG was 8.1 years. The incidence of preoperative reduced ventricular function was 10 per 21 patients (47.6%). A multivariate logistic regression analysis using patient characteristics showed that the time range from acute KD to CABG was the only predictor for ventricular functional deterioration (p=0.03, odds ratio 1.55. 95%CI: 1.033 approximately 2.325). Based on these results, we divided the patients into two groups of short time range (mean: 3.7 years; group S) and long time range (mean: 13.9 years; group L). RESULTS: Preoperative left ventricular functional deterioration was recognized more frequently in group L (9/9, 100%) than in group S (1/12, 8.3%)(p<0.01). Myocardial infarction was documented significantly higher in the group L (6/9, 66.7%) than group S (1/12, 8.3%)(p=0.04). There was no surgical mortality in either group. The arterial grafts demonstrated good potential for growth and graft patency was 96.9%. Moreover, seven of the giant aneurysms proximal to the graft anastomosis showed complete thrombotic occlusion after CABG without development of myocardial infarction. The cardiac events free rate of group L and group S was 66.7% and 100%, respectively, during the postoperative follow up periods of 5.5+/-1.1 years (group L) and 4.7+/-1.1 years (group S). CONCLUSIONS: We successfully applied CABG for Kawasaki coronary disease. Based on our experience, a short interval after acute KD appears to be ideal for surgical treatment of Kawasaki coronary disease.

Evolution of staged approach for Fontan operation.

BACKGROUND: During the early development of the Fontan operation, a number of physiologic and anatomical limits were proposed as selection criteria, and two criteria, pulmonary vascular resistance and ventricular function, have been important in predicting surgical outcome. The use of the bidirectional cavo pulmonary shunt as a staging procedure performed to control the pulmonary blood flow adequately and reduce ventricular volume over load has resulted in marked improvements in the early and late Fontan procedure results. METHODS AND RESULTS: At our hospital we perform systemic pulmonary shunt or pulmonary artery banding in patients if pulmonary blood flow can not be controlled adequately in the neonatal period and then perform bidirectional cavo pulmonary shunt six months afterwards. During this operation we also performed simultaneous surgical repair for pulmonary artery distortion, anomalies of pulmonary venous connection, restriction of bulboventricular foramen and atrioventricular valve regurgitation. To determine the efficacy of this staged approach in avoiding increases in pulmonary vascular resistance and impaired ventricular function, surgical results were investigated. From February 1995 to May 2001, eighteen patients with cardiac morphology unsuitable for biventricular repair were admitted to our hospital. Twenty-six palliative procedures, were performed including seven pulmonary artery banding, three systemic pulmonary shunt, thirteen bidirectional cavo pulmonary shunt, one original Glenn procedure, four repair of coarctation of the aorta, two total anomalous pulmonary venous connection repair, one mitral valve plasty, and two patients required Damus-Kaye-Stansel procedure to release restrictive bulboventricular foramen. Fifteen patients underwent a modified Fontan operation (total cavopulmonary connection) after these palliative procedures. The operative mortality rate for these palliative procedures was 3.8% (1/26). The operative mortality rate for Fontan operation was 7.1% (1/14). Three patients awaiting the Fontan operation were considered good candidates for a final operation and no patients in this series were considered unsuitable for Fontan completion. CONCLUSION: Our strategy of staged approach for Fontan procedure offers a good prognosis.

Atrial septal defect with borderline pulmonary vascular disease: surgery and long-term oral prostacyclin therapy for recalcitrant pulmonary hypertension.

The hemodynamic determination of operability in atrial septal defect (ASD) with severe pulmonary hypertension is problematic. Therefore, we perform an open lung biopsy prior to the corrective surgery in cases with pulmonary vascular resistance greater than 8 units x m2 and/or pulmonary arterial peak pressure greater than 70 mmHg. We present 4 cases showing occlusion of more than 70% of the small pulmonary arteries and arterioles by musculoelastosis, thromboembolism and mixed-type (musculoelastosis and plexogenic arteriopathy) which was considered borderline in terms of operability. After complete closure of the ASD and postoperative long-term oral prostacyclin (PGI2) therapy, pulmonary artery peak pressure decreased from 110-72 (mean 84) to 105-45 (mean 74) mmHg immediately after operation and 65-40 (mean 57) mmHg after PGI2 therapy. The New York Heart Association functional status of the patients improved from class II-III to class I with oral PGI2 only. Our cases demonstrate that despite more than 70% occlusion of the small pulmonary arteries and arterioles, surgery and long-term PGI2 therapy can reduce pulmonary artery pressure and improve the quality of life.

One and a half ventricle repair for Ebstein's anomaly.

The surgical strategy for patients having Ebstein's anomaly and hypoplastic right ventricle is controversial. An 11-year-old boy patient having such condition, with estimated end-diastolic volume index of the atrialized and functional right ventricle being 70% of normally expected values, underwent biventricular repair. Immediately after the surgery, however, he developed right heart failure with the central venous pressure of 11 mmHg. He consequently underwent additional bidirectional cavopulmonary anastomosis, thereby converting the biventricular repair into one and a half ventricle repair. He recovered uneventfully and is doing well 2 years after the surgery.

Performance of cell-penetrating peptide-linked polymers physically mixed with poorly membrane-permeable molecules on cell membranes.

We are investigating a new class of penetration enhancers that enable poorly membrane-permeable molecules physically mixed with them to effectively penetrate cell membranes without their concomitant cellular uptake. Since we previously revealed that poly(N-vinylacetamide-co-acrylic acid) modified with d-octaarginine, which is a typical cell-penetrating peptide, significantly enhanced the nasal absorption of insulin, we examined the performance of the polymers on cell membranes. When Caco-2 cells were incubated with 5(6)-carboxyfluorescein (CF) for 30 min, approximately 0.1% of applied CF was internalized into the cells. This poor membrane permeability was dramatically enhanced by d-octaarginine-linked polymers; a 25-fold increase in the cellular uptake of CF was observed when the polymer concentration was adjusted to 0.2mg/mL. None of the individual components, for example, d-octaarginine, had any influence on CF uptake, demonstrating that only d-octaarginine anchored chemically to the polymeric platform enhanced the membrane permeation of CF. The polymer-induced CF uptake was consistently high even when the incubation time was extended to 120 min. Confocal laser scanning microphotographs of cells incubated with d-octaarginine-linked polymers bearing rhodamine red demonstrated that the cell outline was stained with red fluorescence. The polymer-induced CF uptake was significantly suppressed by 5-(N-ethyl-N-isopropyl)amiloride, which is an inhibitor of macropinocytosis. Results indicated that d-octaarginine-linked polymers remained on the cell membrane and poorly membrane-permeable CF was continuously internalized into cells mainly via macropinocytosis repeated for the individual peptidyl branches in the polymer backbone.

Microdialysis assessment of percutaneous penetration of ketoprofen after transdermal administration to hairless rats and domestic pigs.

The study was performed to evaluate the percutaneous penetration of ketoprofen after transdermal administration using a microdialysis technique in pigs, in comparison with rats. Ketoprofen release from patches was determined by analysis of the remaining drug content after application to hairless rats and pigs. Skin and knee joint penetration of ketoprofen was tested by microdialysis, and recovery was determined by retrodialysis. Residual rates in hairless rats and pigs were 68.1 ± 1.6% and 81.7 ± 4.4%, respectively, at 10h. The average recoveries of ketoprofen over 480 min in the skin and knee joint cases were 72.0 ± 3.4% and 9.8 ± 6.2% in rats and 72.3 ± 2.5% and 57.6 ± 3.1% in pigs, respectively. In rats, ketoprofen was rapidly absorbed with transdermal administration, with C(max) values of 191.7 ± 76.2 and 35.5 ± 21.7 ng/mL and AUC(0-8h) values of 918.2 ± 577.5 and 195.9 ± 137.1 ngh/mL, respectively, for the skin and knee joint. The C(max) values for the pig were 20.9 ± 18.5 and 3.7 ± 3.0 ng/mL, with AUC(0-8h) values of 73.1 ± 69.2 and 16.1 ± 16.1 ngh/mL. Ketoprofen concentrations within skin and knee joint of non-application sites in rats and pigs were less than 0.8 ng/mL. Transdermal administration of ketoprofen significantly reduced prostaglandin E2 levels in the skin of the application site and showed a tendency for inhibition in the knee joint. We thus demonstrated that topical patches containing ketoprofen can deliver the drug through the skin and knee joint of pigs and rats via direct diffusion, and microdialysis data with the pig may be useful for the prediction of human tissue penetration of drugs with transdermal administration.

Etoposide induces growth arrest and disrupts androgen receptor signaling in prostate cancer cells.

Androgen and androgen receptor (AR)-mediated signaling are crucial for the development of prostate cancer. The present study indicates that the topoisomerase II inhibitor etoposide strikingly inhibits androgen/AR-mediated cell growth and androgen-stimulated DNA synthesis in prostate cancer cells. Etoposide significantly repressed the AR mRNA and protein expression in a dose-dependent manner. Etoposide-mediated down-regulation of AR was associated with blocking androgen-induced AR translocation from cytoplasm into nucleus of cells. Additionally, etoposide disrupted the association of AR and heat shock protein 90 and impeded binding of the synthetic androgen [3H]R1881 to AR in LNCaP cells. Etoposide simultaneously reduced the intracellular and secreted PSA levels, a marker for the progression of prostate cancer. These findings collectively reveal that etoposide not only serves as a traditional genotoxic agent but directly targets AR as an AR disrupting therapeutic strategy in prostate cancer.