Therapeutic ultrasound treatment for the prevention of chronic kidney disease-associated muscle wasting in mice.

Low-intensity pulsed ultrasound (LIPUS) is a kind of therapeutic ultrasound. It can help improve bone fracture repair and soft tissue healing. Our previous study found that LIPUS treatment could halt the chronic kidney disease (CKD) progression in mice; unexpectedly, we observed the improvement of CKD-reduced muscle weights by LIPUS treatment. Here, we further tested the protective potential of LIPUS on CKD-associated muscle wasting/sarcopenia using the CKD mouse models. Mouse models of both unilateral renal ischemia/reperfusion injury (IRI) with nephrectomy and adenine administration were used to induce CKD. LIPUS with condition of 3 MHz, 100 mW/cm2, 20 min/day was applied to the kidney of CKD mice. LIPUS treatment significantly reversed the increased serum BUN/creatinine levels in CKD mice. LIPUS effectively prevented the decrease in grip strength, muscle weight (soleus, tibialis anterior, and gastrocnemius muscles), cross-section areas of muscle fibres, and muscular phosphorylated Akt protein expression by immunohistochemistry, and the increase in muscular atrogenes Atrogin1 and MuRF1 protein expression by immunohistochemistry in CKD mice. These results indicated that LIPUS could help improve weak muscle strength, muscle mass loss, muscle atrophy-related protein expression, and Akt inactivation. LIPUS application may be an alternative non-invasive therapeutic intervention on the management of CKD-associated muscle wasting.

Determining plasma and cerebrospinal fluid concentrations of EGFR-TKI in lung cancer patients.

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) are commonly used to treat advanced non-small cell lung cancer (NSCLC). A rapid and reliable method for measuring plasma and cerebrospinal fluid (CSF) concentrations of EGFR-TKIs is needed for therapeutic drug monitoring. By using UHPLC‒MS/MS with multiple reaction monitoring mode, we developed a method for rapidly determining the plasma and CSF concentrations of gefitinib, erlotinib, afatinib, and osimertinib. Protein precipitation was employed to remove protein interference for plasma and CSF matrix. The LC‒MS/MS assay was validated to be satisfactory in terms of linearity, precision, and accuracy. This method was successfully applied to measure plasma (n = 44) and CSF (n = 6) concentrations of EGFR-TKIs in NSCLC patients. The chromatographic separation was achieved by a Hypersil Gold aQ column within 3 min. The median plasma concentrations were 325.76, 1981.50, 42.62, 40.27, and 340.92 ng/ml for gefitinib erlotinib, afatinib 30 mg/day, afatinib 40 mg/day, and osimertinib, respectively. The CSF penetration rates were 2.15% for the patients receiving erlotinib therapy, 0.59% for afatinib, 0.08-1.12% for osimertinib 80 mg/day, and 2.18% for those receiving osimertinib 160 mg/day. This assay helps to predict the effectiveness and toxicities of EGFR-TKIs in the pursuit of precision medicine for lung cancer patients.

A ubiquitous endocrine disruptor tributyltin induces muscle wasting and retards muscle regeneration.

BACKGROUND: Organotin pollutant tributyltin (TBT) is an environmental endocrine disrupting chemical and is a known obesogen and diabetogen. TBT can be detected in human following consumption of contaminated seafood or water. The decrease in muscle strength and quality has been shown to be associated with type 2 diabetes in older adults. However, the adverse effects of TBT on the muscle mass and function still remain unclear. Here, we investigated the effects and molecule mechanisms of low-dose TBT on skeletal muscle regeneration and atrophy/wasting using the cultured skeletal muscle cell and adult mouse models. METHODS: The mouse myoblasts (C2C12) and differentiated myotubes were used to assess the in vitro effects of low-dose tributyltin (0.01-0.5 µM). The in vivo effects of TBT at the doses of 5 and 25 µg/kg/day (n = 6/group), which were five times lower than the established no observed adverse effect level (NOAEL) and equal to NOAEL, respectively, by oral administration for 4 weeks on muscle wasting and muscle regeneration were evaluated in a mouse model with or without glycerol-induced muscle injury/regeneration. RESULTS: TBT reduced myogenic differentiation in myoblasts (myotube with 6-10 nuclei: 53.9 and 35.8% control for 0.05 and 0.1 µM, respectively, n = 4, P < 0.05). TBT also decreased myotube diameter, upregulated protein expression levels of muscle-specific ubiquitin ligases (Atrogin-1 and MuRF1), myostatin, phosphorylated AMPKα, and phosphorylated NFκB-p65, and downregulated protein expression levels of phosphorylated AKT and phosphorylated FoxO1 in myotubes (0.2 and 0.5 µM, n = 6, P < 0.05). Exposure of TBT in mice elevated body weight, decreased muscle mass, and induced muscular dysfunction (5 and 25 µg/kg, P > 0.05 and P < 0.05, respectively, n = 6). TBT inhibited soleus muscle regeneration in mice with glycerol-induced muscle injury (5 and 25 µg/kg, P > 0.05 and P < 0.05, respectively, n = 6). TBT upregulated protein expression levels of Atrogin-1, MuRF1, myostatin, and phosphorylated AMPKα and downregulated protein expression level of phosphorylated FoxO1 in the mouse soleus muscles (5 and 25 µg/kg, P > 0.05 and P < 0.05, respectively, n = 6). CONCLUSIONS: This study demonstrates for the first time that low-dose TBT significantly inhibits myogenic differentiation and triggers myotube atrophy in a cell model and significantly decreases muscle regeneration and muscle mass and function in a mouse model. These findings suggest that low-dose TBT exposure may be an environmental risk factor for muscle regeneration inhibition, atrophy/wasting, and disease-related myopathy.

Low-dose tributyltin triggers human chondrocyte senescence and mouse articular cartilage aging.

Tributyltin (TBT) is known as an endocrine-disrupting chemical. This study investigated the effects and possible mechanisms of TBT exposure on inducing human articular chondrocyte senescence in vitro at the human-relevant concentrations of 0.01-0.5 µM and mouse articular cartilage aging in vivo at the doses of 5 and 25 µg/kg/day, which were 5 times lower than the established no observed adverse effect level (NOAEL) and equal to NOAEL, respectively. TBT significantly increased the senescence-associated ß-galactosidase activity and the protein expression levels of senescence markers p16, p53, and p21 in chondrocytes. TBT induced the protein phosphorylation of both p38 and JNK mitogen-activated protein kinases in which the JNK signaling was a main pathway to be involved in TBT-induced chondrocyte senescence. The phosphorylation of both ataxia-telangiectasia mutated (ATM) and histone protein H2AX (termed γH2AX) was also significantly increased in TBT-treated chondrocytes. ATM inhibitor significantly inhibited the protein expression levels of γH2AX, phosphorylated p38, phosphorylated JNK, p16, p53, and p21. TBT significantly stimulated the mRNA expression of senescence-associated secretory phenotype (SASP)-related factors, including IL-1ß, TGF-ß, TNF-α, ICAM-1, CCL2, and MMP13, and the protein expression of GATA4 and phosphorylated NF-κB-p65 in chondrocytes. Furthermore, TBT by oral gavage for 4 weeks in mice significantly enhanced the articular cartilage aging and abrasion. The protein expression of phosphorylated p38, phosphorylated JNK, GATA4, and phosphorylated NF-κB-p65, and the mRNA expression of SASP-related factors were enhanced in the mouse cartilages. These results suggest that TBT exposure can trigger human chondrocyte senescence in vitro and accelerating mouse articular cartilage aging in vivo.

Sudden quadriparesis after non-overdose local anesthesia.

BACKGROUND: A well-known anesthetic, lidocaine is the most widely used local anesthetic. Local anesthetic systemic toxicity (LAST) is a life-threatening event with common and prominent presentations of central nervous system (CNS) toxicity and cardiovascular toxicity. The most frequent and prominent early warning signs and symptoms of LAST are central nervous system symptoms. While rare, cases quadriparesis after the administration of lidocaine has been reported. CASE PRESENTATION: In this paper, we report a very rare case of quadriparesis after local anesthesia administration for vocal cord cyst-removal surgery, which dramatically improved after treatment. LAST can occur during various routes of lidocaine administration, such as local spray. A possible mechanism of our case could be the local diffusion of lidocaine to the spinal cord, which caused the symptoms to mimic anterior cord syndrome. CONCLUSIONS: Our case presented a favorable outcome following the administration of intravenous lipid emulsion (ILE) for non-over dose local anesthetic drug induced spinal cord inhibition symptoms. These findings highlight the need for further research on the use of ILE to reverse LAST and other adverse effects of local anesthetics.

Determination of synthetic cathinone α-pyrrolidinovalero-phenone and its metabolite in urine using solid-phase extraction and gas chromatography-mass spectrometry.

RATIONALE: The presence of α-pyrrolidinovalerophenone (α-PVP) and its metabolites in urine is evidence of the administration of α-PVP. A toxicological challenge is that the metabolites of α-PVP exhibit amphoteric properties, which make them unsuitable for detection using gas chromatography-mass spectrometry (GC/MS). In the study reported, proper derivatization and sample extraction were essential for improving the sensitivity for GC/MS analysis. METHODS: An automated solid-phase extraction (SPE) method has been developed and optimized. The derivatization efficiency was tested using longer reaction time and the addition of polar pyridine into a mixture of N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane. Method validation, including linearity, limit of detection, precision, accuracy, and recovery, was evaluated using automatic SPE and GC/MS. RESULTS: The results suggested that adding pyridine to BSTFA (1:1, v/v) significantly improved derivatization efficiency and precision. After optimization, the linear range was from 25 to 1000 ng mL-1 with R2 > 0.9950. The limit of detection was 5 ng mL-1 for α-PVP and 25 ng mL-1 for OH-α-PVP. The recovery for SPE was over 88%. The inter-day and intra-day precisions were less than 15%. A forensic sample has been found containing α-PVP (67.3 ng mL-1 ) and OH-α-PVP (560.2 ng mL-1 ). CONCLUSIONS: This study is the first to validate an auto-SPE-GC/MS method for the quantification and qualification of α-PVP and OH-α-PVP in urine. We have successfully improved the derivatization efficiency and developed a sensitive and semi-automatic approach. This approach is desirable for the detection of synthetic cathinone at trace levels in biological samples.

Exposure of Macrophages to Low-Dose Gadolinium-Based Contrast Medium: Impact on Oxidative Stress and Cytokines Production.

The toxicity of gadolinium-based contrast agents (GBCAs) has drawn a lot of attention. Nephrogenic systemic fibrosis (NSF), a lethal disease related to the use of GBCAs, is still not understood. Recently, gadolinium retention is found in brain tissues after repeated use of GBCAs in magnetic resonance imaging (MRI). However, most of the works investigating the toxicity of GBCAs are focusing on its high-concentration (0.5-10 mM) part, which is not reflective of the physiological conditions in human beings. Macrophages play a regulatory role in immune responses and are responsible for the fibrosis process. Their role in gadolinium retention and the pathogenesis of NSF, however, has seldom been investigated. This study aimed to evaluate the immune response generated by macrophages (RAW 264.7) exposing to low levels of GBCAs. The incubation concentration of GBCAs, including Omniscan®, Primovist®, Magnevist®, and Gadovist®, is proportional to the level of gadolinium uptake when detected via inductively coupled plasma mass spectrometry (ICP-MS) and imaged by MRI, whereas Primovist® treatment groups have highest gadolinium uptake among all of the tested concentrations. Low-concentration (2.5 µmol/L) Gd chloride or GBCAs exposure promoted the reactive production of oxygen species (ROS), nitrate/nitrite, prostaglandin E2 (PGE2), and suppressed the potential of mitochondrial membrane. There was higher ROS, nitrate/nitrite, and PGE2 production in the Primovist®, Omniscan®, and Magnevist® groups compared to the Gadovist® group. In face of lipopolysaccharide (LPS) stimulation, Primovist®, Omniscan®, and Magnevist® groups exhibited elevated nitrite/nitrate and suppressed IL-1ß secretion and IL-6 and IL-10 secretion. Moreover, upon LPS stimulation, there is decreased TNF-α secretion 4 hours after Primovist® or Omiscan® exposure but the TNF-α secretion increased at 24 hours. Our data suggest that there is upregulated inflammation even in the presence of low levels of GBCAs, even similar to the physiological condition in murine macrophage. Further investigation of GBCAs on the human macrophage or in vivo animal study may clarify the role of macrophage on the pathogenesis of NSF and other GBCAs-related disease.

Salidroside ameliorates sepsis-induced acute lung injury and mortality via downregulating NF-κB and HMGB1 pathways through the upregulation of SIRT1.

Sepsis is a life-threatening medical condition. Salidroside, a substance isolated from Rhodiola rosea, possesses antioxidant and anti-inflammatory properties. The effect and mechanism of salidroside on sepsis-induced acute lung injury still remains to be well clarified. Here, we investigated the effect and mechanism of salidroside on septic mouse models and explored the role of salidroside-upregulated SIRT1. Salidroside inhibited the inflammatory responses and HMGB1 productions in bacterial lipopolysaccharide (LPS)-treated macrophages and mice. Salidroside could also reverse the decreased SIRT1 protein expression in LPS-treated macrophages and mice. Salidroside also alleviated the sepsis-induced lung edema, lipid peroxidation, and histopathological changes and the mortality, and improved the lung PaO2/FiO2 ratio in cecal ligation and puncture (CLP)-induced septic mice. Salidroside significantly decreased the serum TNF-α, IL-6, NO, and HMGB1 productions, pulmonary inducible NO synthase (iNOS) and phosphorylated NF-κB-p65 protein expressions, and pulmonary HMGB1 nuclear translocation in CLP septic mice. Moreover, sepsis decreased the SIRT1 protein expression in the lungs of CLP septic mice. Salidroside significantly upregulated the SIRT1 expression and inhibited the inflammatory responses in CLP septic mouse lungs. These results suggest that salidroside protects against sepsis-induced acute lung injury and mortality, which might be through the SIRT1-mediated repression of NF-κB activation and HMGB1 nucleocytoplasmic translocation.

Tributyltin exposure at noncytotoxic doses dysregulates pancreatic ß-cell function in vitro and in vivo.

Tributyltin (TBT) is an endocrine disruptor. TBT can be found in food and in human tissues and blood. Several animal studies revealed that organotins induced diabetes with decreased insulin secretion. The detailed effect and mechanism of TBT on pancreatic ß-cell function still remain unclear. We investigated the effect and mechanism of TBT exposure at noncytotoxic doses relevant to human exposure on ß-cell function in vitro and in vivo. The ß-cell-derived RIN-m5F cells and pancreatic islets from mouse and human were treated with TBT (0.05-0.2 µM) for 0.5-4 h. Adult male mice were orally exposed to TBT (25 µg/kg/day) with or without antioxidant N-acetylcysteine (NAC) for 1-3 weeks. Assays for insulin secretion and glucose metabolism were carried out. Unlike previous studies, TBT at noncytotoxic concentrations significantly increased glucose-stimulated insulin secretion and intracellular Ca2+ ([Ca2+]i) in ß-cells. The reactive oxygen species (ROS) production and phosphorylation of protein kinase C (PKC-pan) and extracellular signal-regulated kinase (ERK)1/2 were also increased. These TBT-triggered effects could be reversed by antiestrogen ICI182780 and inhibitors of ROS, [Ca2+]i, and PKC, but not ERK. Similarly, islets treated with TBT significantly increased glucose-stimulated insulin secretion, which could be reversed by ICI182780, NAC, and PKC inhibitor. Mice exposed to TBT for 3 weeks significantly increased blood glucose and plasma insulin and induced glucose intolerance and insulin resistance, which could be reversed by NAC. These findings suggest that low/noncytotoxic doses of TBT induce insulin dysregulation and disturb glucose homeostasis, which may be mediated through the estrogen receptor-regulated and/or oxidative stress-related signaling pathways.

Transplantation of human skeletal muscle-derived progenitor cells ameliorates knee osteoarthritis in streptozotocin-induced diabetic mice.

The epidemiological and experimental evidence suggests that diabetes can be an independent risk factor for osteoarthritis. The osteoarthritis-like cartilage damage has been shown in streptozotocin-induced diabetic mice. The therapeutic effects of human skeletal muscle-derived progenitor cells (HSMPCs) on diabetic osteoarthritis still remain unclear. Here, we investigated the therapeutic potential of HSMPCs on diabetic knee osteoarthritis. The in vitro chondrogenic ability of HSMPCs was determined by pellet culture assay. Male mice were used to develop the model of streptozotocin-induced type 1 diabetes and its related osteoarthritis. HSMPCs were injected intra-articularly to rescue osteoarthritis. Protein expressions of advanced glycation end-products, cyclooxygenase-2, and type-2 collagen in tissues were determined by immunohistochemistry. The pellet culture assay showed that HSMPCs cultured in differentiation medium for chondrogenesis significantly produced larger pellets with an overproduction of extracellular matrix than in growth medium. In in vivo experiments, intra-articular injection of HSMPCs for 4 weeks significantly prevented the progression of degenerative changes in the cartilage of streptozotocin-induced diabetic mice, including an obvious increase of total articular cartilage thickness and a decrease of fibrous cartilage thickness. HSMPCs transplantation also exerted the decline in advanced glycation end-products and cyclooxygenase-2 protein expression, but increased the type-2 collagen protein expression in streptozotocin-induced osteoarthritic cartilages. Moreover, HSMPCs transplantation also inhibited the increased serum interleukin-6 and matrix metalloproteinase-3 levels in diabetic mice. These results demonstrated for the first time that HSMPCs transplantation ameliorates cartilage degeneration in diabetes-related osteoarthritis mice. These findings suggest that HSMPCs transplantation may apply as a potential therapeutic use of diabetes-related osteoarthritis. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1886-1893, 2017.

Hemorrhagic cystitis in children treated with alkylating agent cyclophosphamide: The experience of a medical center in Taiwan.

BACKGROUND/PURPOSE: Hemorrhagic cystitis is a common complication with chemotherapeutic alkylating agents. We investigated the possible prognostic factors of cyclophosphamide-induced hemorrhagic cystitis in children. METHODS: Medical records of children (< 18 years old) with cyclophosphamide-related hemorrhagic cystitis were collected retrospectively from January 2000 to December 2010 in a tertiary care center. We also prospectively enrolled children (< 18 years old) with cyclophosphamide treatment. RESULTS: The retrospective study consisted of 23 patients whose median age was 11 years. The median day of onset time was 1 day after cyclophosphamide usage. The hemato-oncological diseases included acute leukemia (39.1%), lymphoma (13%), blastoma (13%), sarcoma (13%), aplastic anemia (13%), and others (8.7%). Patients who received bone marrow transplantation (BMT) had significantly longer duration of hemorrhagic cystitis than those who did not receive BMT (p < 0.05). Serum uric acid, checked prior to and after the onset of hemorrhage cystitis, was significantly lower after the development of hemorrhagic cystitis (p < 0.05). In the prospective study, 11 children were enrolled with a median age of 5 years. The urinary nitrite/nitrate and 8-iso-prostaglandin F2α levels increased significantly after cyclophosphamide usage (p < 0.05). CONCLUSION: Alteration serum uric acid level and BMT could be indicators for severe hemorrhagic cystitis. The elevated levels of urinary nitrite/nitrate and 8-iso-prostaglandin F2α may indicate the essential roles played by nitric oxide syntheses and reactive oxidative stress in cyclophosphamide-induced hemorrhagic cystitis. These findings may help clinicians formulate a better strategy for treating cyclophosphamide-induced hemorrhagic cystitis.

C/EBP homologous protein deficiency aggravates acute pancreatitis and associated lung injury.

AIM: To investigate the pathophysiological role of C/EBP homologous protein (CHOP) in severe acute pancreatitis and associated lung injury. METHODS: A severe acute pancreatitis model was induced with 6 injections of cerulein (Cn, 50 µg/kg) at 1-h intervals, then intraperitoneal injection of lipopolysaccharide (LPS, 7.5 mg/kg) in CHOP-deficient (Chop(-/-)) mice and wild-type (WT) mice. Animals were sacrificed under anesthesia, 3 h or 18 h after LPS injection. Serum amylase, lipase, and cytokines [interleukin (IL)-6 and tumor necrosis factor (TNF)-α], pathological changes, acute lung injury, and apoptosis in the pancreas were evaluated. Serum amylase and lipase activities were detected using a medical automatic chemical analyzer. Enzyme-linked immunosorbent assay kits were used to evaluate TNF-α and IL-6 levels in mouse serum and lung tissue homogenates. Apoptotic cells in sections of pancreatic tissues were determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) analysis. The mouse carotid arteries were cannulated and arterial blood samples were collected for PaO2 analysis. The oxygenation index was expressed as PaO2/FiO2. RESULTS: Administration of Cn and LPS for 9 and 24 h induced severe acute pancreatitis in Chop(-/-) and WT mice. When comparing Chop(-/-) mice and WT mice, we observed that CHOP-deficient mice had greater increases in serum TNF-α (214.40 ± 19.52 pg/mL vs 150.40 ± 16.70 pg/mL; P = 0.037), amylase (4236.40 ± 646.32 U/L vs 2535.30 ± 81.83 U/L; P = 0.041), lipase (1678.20 ± 170.57 U/L vs 1046.21 ± 35.37 U/L; P = 0.008), and IL-6 (2054.44 ± 293.81 pg/mL vs 1316.10 ± 108.74 pg/mL; P = 0.046) than WT mice. The histopathological changes in the pancreases and lungs, decreased PaO2/FiO2 ratio, and increased TNF-α and IL-6 levels in the lungs were greater in Chop(-/-) mice than in WT mice (pancreas: Chop(-/-) vs WT mice, hemorrhage, P = 0.005; edema, P = 0.005; inflammatory cells infiltration, P = 0.005; total scores, P = 0.006; lung: hemorrhage, P = 0.017; edema, P = 0.017; congestion, P = 0.017; neutrophil infiltration, P = 0.005, total scores, P = 0.001; PaO2/FiO2 ratio: 393 ± 17.65 vs 453.8, P = 0.041; TNF-α: P = 0.043; IL-6, P = 0.040). Results from TUNEL analysis indicated increased acinar cell apoptosis in mice following the induction of acute pancreatitis. However, Chop(-/-) mice displayed significantly reduced pancreatic apoptosis compared with the WT mice (201.50 ± 31.43 vs 367.00 ± 47.88, P = 0.016). CONCLUSION: These results suggest that CHOP can exert protective effects against acute pancreatitis and limit the spread of inflammatory damage to the lungs.

Screening and confirmation of 62 drugs of abuse and metabolites in urine by ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry.

An ultra-high-performance liquid chromatography--quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) method for the screening and confirmation of 62 drugs of abuse and their metabolites in urine was developed in this study. The most commonly abused drugs, including amphetamines, opioids, cocaine, benzodiazepines (BZDs) and barbiturates, and many other new and emerging abused drugs, were selected as the analytes for this study. Urine samples were diluted 5-fold with deionized water before analysis. Using a superficially porous micro-particulate column and an acetic acid-based mobile phase, 54 basic and 8 acidic analytes could be detected within 15 and 12 min in positive and negative ionization modes, respectively. The MS collision energies for the 62 analytes were optimized, and their respective fragmentation patterns were constructed in the in-house library for confirmatory analysis. The coefficients of variation of the intra- and inter-day precision of the analyte responses all were <17.39%. All analytes, except barbital, showed matrix effects of 77-121%. The limits of detection of the 62 analytes were between 2.8 and 187.5 ng/mL, which were lower than their respective cut-off concentrations (20-500 ng/mL). Ten urine samples from patients undergoing methadone treatment were analyzed by the developed UHPLC-QTOF-MS method, and the results were compared with the immunoassay method.

Involvement of interleukin-6-regulated nitric oxide synthase in hemorrhagic cystitis and impaired bladder contractions in young rats induced by acrolein, a urinary metabolite of cyclophosphamide.

Hemorrhagic cystitis is a common complication in children receiving cyclophosphamide, a chemotherapeutic alkylating agent. Acrolein is a urinary metabolite from cyclophosphamide and can induce hemorrhagic cystitis. Here, we investigated the effects and mechanisms of acrolein by intravesical instillation on urinary bladder muscle contractions and pathological alterations in rats. Acrolein instillation significantly increased the muscle contractions of rat bladder detrusor after 1 and 6 h but markedly decreased detrusor contractions after 24 h. Acrolein increased phosphorylated protein kinase C (pan-PKC) expressions in bladders after 1 and 6 h but inhibited it after 24 h. Inducible nitric oxide (NO) synthase (iNOS) protein expressions were markedly induced in bladders 24 h after acrolein treatment. Twenty-four-hour acrolein instillation increased the levels of nitrite/nitrate and interleukin-6 (IL-6) in the urinary bladder. The iNOS inhibitors significantly inhibited the acrolein-increased nitrite/nitrate levels, but not IL-6 levels. IL-6-neutralizing antibodies effectively inhibited the acrolein-increased NOx levels. The increased detrusor contractions by 1-h acrolein treatment were significantly reversed by the PKC inhibitor RO32-0432, and the decreased detrusor contractions by 24-h acrolein treatment were significantly reversed by the iNOS inhibitor and IL-6-neutralizing antibody. Both the iNOS inhibitor and IL-6-neutralizing antibody effectively reversed the increased iNOS expression, decreased PKC phosphorylation, increased bladder weight, and hemorrhagic cystitis in rats 24 h after acrolein treatment. Taken together, these results suggest that an IL-6-regulated iNOS/NO signaling pathway participates in the acrolein-triggered detrusor contraction inhibition and hemorrhagic cystitis. These findings may help us to find a new strategy to treat cyclophosphamide-induced hemorrhagic cystitis.

Down-regulation of glucose-regulated protein (GRP) 78 potentiates cytotoxic effect of celecoxib in human urothelial carcinoma cells.

Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor that has been reported to elicit anti-proliferative response in various tumors. In this study, we aim to investigate the antitumor effect of celecoxib on urothelial carcinoma (UC) cells and the role endoplasmic reticulum (ER) stress plays in celecoxib-induced cytotoxicity. The cytotoxic effects were measured by MTT assay and flow cytometry. The cell cycle progression and ER stress-associated molecules were examined by Western blot and flow cytometry. Moreover, the cytotoxic effects of celecoxib combined with glucose-regulated protein (GRP) 78 knockdown (siRNA), (-)-epigallocatechin gallate (EGCG) or MG132 were assessed. We demonstrated that celecoxib markedly reduces the cell viability and causes apoptosis in human UC cells through cell cycle G1 arrest. Celecoxib possessed the ability to activate ER stress-related chaperones (IRE-1α and GRP78), caspase-4, and CCAAT/enhancer binding protein homologous protein (CHOP), which were involved in UC cell apoptosis. Down-regulation of GRP78 by siRNA, co-treatment with EGCG (a GRP78 inhibitor) or with MG132 (a proteasome inhibitor) could enhance celecoxib-induced apoptosis. We concluded that celecoxib induces cell cycle G1 arrest, ER stress, and eventually apoptosis in human UC cells. The down-regulation of ER chaperone GRP78 by siRNA, EGCG, or proteosome inhibitor potentiated the cytotoxicity of celecoxib in UC cells. These findings provide a new treatment strategy against UC.

Honokiol attenuates the severity of acute pancreatitis and associated lung injury via acceleration of acinar cell apoptosis.

Severe acute pancreatitis remains a life-threatening disease with a high mortality rate among a defined proportion of those affected. Apoptosis has been hypothesized to be a beneficial form of cell death in acute pancreatitis. Honokiol, a low-molecular-weight natural product, possesses the ability of anti-inflammation and apoptosis induction. Here, we investigate whether honokiol can ameliorate severe acute pancreatitis and the associated acute lung injury in a mouse model. Mice received six injections of cerulein at 1-h intervals, then given one intraperitoneal injection of bacterial lipopolysaccharide for the induction of severe acute pancreatitis. Moreover, mice were intraperitoneally given vehicle or honokiol 10 min after the first cerulein injection. Honokiol protected against the severity of acute pancreatitis in terms of increased serum amylase and lipase levels, pancreas pathological injury, and associated acute lung injury. Honokiol significantly reduced the increases in serum tumor necrosis factor-α, interleukin 1, and nitric oxide levels 3 h and serum high-mobility group box 1 24 h after acute pancreatitis induction. Honokiol also significantly decreased myeloperoxidase activities in the pancreas and the lungs. Endoplasmic reticulum stress-related molecules eIF2α (phosphorylated) and CHOP protein expressions, apoptosis, and caspase-3 activity were increased in the pancreas of mice with severe acute pancreatitis, which was unexpectedly enhanced by honokiol treatment. These results suggest that honokiol protects against acute pancreatitis and limits the spread of inflammatory damage to the lung in a severe acute pancreatitis mouse model. The acceleration of pancreatic cell apoptosis by honokiol may play a pivotal role.

Honokiol rescues sepsis-associated acute lung injury and lethality via the inhibition of oxidative stress and inflammation.

PURPOSE: Sepsis has a high mortality rate despite the recent advances in intensive care medicine and antibiotics. Honokiol, a low molecular weight natural product, is known to possess anti-inflammatory activity. Here, we investigate whether honokiol can ameliorate acute lung injury and lethal response in murine models of sepsis. METHODS: Mice were intraperitoneally given vehicle or honokiol 30 min after the induction of sepsis by cecal ligation and puncture (CLP) and endotoxemia by administration of E. coli lipopolysaccharide (LPS). RESULTS: The productions of serum tumor necrosis factor-α (TNF-α), nitric oxide (NO), and high mobility group box 1 (HMGB 1) were increased in mice during sepsis, which could be reversed by honokiol. Honokiol could also effectively reduce the increased blood lipid peroxidation and nitrotyrosine in septic mice. Honokiol significantly reversed the inductions of inducible NO synthase and nuclear factor-κB (NF-κB) activation in the lungs of mice during sepsis. Honokiol also effectively rescued the lung edema, lung pathological changes, and lethality in septic mice. CONCLUSIONS: These findings suggest that honokiol is capable of suppressing the lethal response and acute lung injury associated with sepsis, and support the potential use of honokiol as a therapeutic agent for the conditions associated with septic shock.

Uropathogenic Escherichia coli-induced inflammation alters mouse urinary bladder contraction via an interleukin-6-activated inducible nitric oxide synthase-related pathway.

Escherichia coli is the most common cause of urinary tract infection. Elevated blood and urine interleukin-6 (IL-6) levels have been shown in inflammatory urinary tract diseases. The role of IL-6 in mediating the urodynamic dysfunction in response to E. coli-induced urinary tract infection has not yet been fully elucidated. In this study, we investigated the role of IL-6 in the nitric oxide (NO)-triggered alteration of contractile responses in the urinary bladder under an E. coli-induced inflammatory condition. The electrical field stimulation (EFS)-evoked contractions of the isolated detrusor strips, and immunoblotting for detecting protein expression in the bladders was measured short term (1 h) or long term (6 or 24 h) after intraperitoneal injection of E. coli endotoxin (lipopolysaccharide [LPS]) or intravesical instillation of human pyelonephritogenic E. coli-J96 (O4:K6) strain or LPS into mice. IL-6 and NO productions were increased in the urinary bladders of mice 1 to 24 h after LPS or E. coli-J96 treatment. Inducible NO synthase (iNOS) expression and protein kinase C (PKC) activation and EFS-evoked detrusor contractions were increased in the bladders at 6 h after LPS or E. coli-J96 treatment, which could be reversed by anti-IL-6 antibody and iNOS inhibitor aminoguanidine. At 1 h after LPS administration, bladder NO generation, endothelial NOS expression, and EFS-evoked detrusor contractions were effectively increased, whereas anti-IL-6 antibody could not reverse these LPS-induced responses. These results indicate that IL-6 may play an important role in the iNOS/NO-triggered PKC-activated contractile response in urinary bladder during E. coli or LPS-induced inflammation.

Uropathogenic Escherichia coli alters muscle contractions in rat urinary bladder via a nitric oxide synthase-related signaling pathway.

BACKGROUND: Uropathogenic Escherichia coli (UPEC) is a common cause of urinary-tract infection. The mechanisms by which bacteria cause the symptoms of cystitis remain unclear. METHODS: The contractions of isolated rat detrusor strips evoked by electrical field stimulations (EFS) or by exogenous agonists and immunoblotting for the detection of protein expression in the bladder were measured in the short (1 h) and long (24 h) term after the intravesical instillation of J96 (O4:K6) strain or UPEC isolated from patients with acute E. coli pyelonephritis or E. coli lipopolysaccharide (LPS). RESULTS: One hour after the instillation of UPEC, the level of endothelial nitric oxide synthase (eNOS) and the contractile response, but not protein kinase C (PKC) and extracellular signal-regulated kinase (ERK)-1/2 activation, were higher. Twenty-four hours after UPEC treatment, detrusor contractions were decreased, and inducible (i) NOS protein expression and ERK1/2 phosphorylation, but not PKC activation, were observed. Both aminoguanidine and PD98059 treatment markedly reversed the decrease of EFS- and acetylcholine-evoked detrusor contractions induced by UPEC. The instillation of LPS triggered PKC activation but not ERK1/2 phosphorylation. CONCLUSIONS: Short-term intravesical instillation of UPEC enhances detrusor contractions through an eNOS-related pathway, but iNOS-regulated ERK1/2 signaling may be involved in long-term UPEC treatment-induced responses. There are different mechanisms involved in the responses induced by UPEC and LPS.

A patient-tailored N-acetylcysteine protocol for acute acetaminophen intoxication.

BACKGROUND: Hepatotoxicity as a result of acetaminophen(APAP) intoxication has become an important problem, but early intervention with N-acetylcysteine (NAC) is effective in preventing hepatic injury. Two NAC regimens are currently approved for acute APAP intoxication: NAC administered orally every 4 hours for 72 hours, and NAC administered intravenously for 20 hours within 8 to 10 hours after ingestion of a potentially hepatotoxic amount of APAP. However, clinical observations suggest that a variable treatment duration may be more appropriate than use of these predetermined, fixed-duration protocols. OBJECTIVES: This study investigated the tolerability and efficacy of a patient-tailored NAC protocol for acute APAP intoxication by comparing the incidence of hepatotoxicity in patients receiving this protocol and in historical controls receiving 1 of 2 fixed-duration protocols: oral NAC for 72 hours and intravenous NAC for 20 hours within 8 to 10 hours after ingestion of a potentially hepatotoxic amount of APAP. METHODS: This was a retrospective case series study that included all patients admitted through the emergency department (ED) of the National Taiwan University Hospital with a diagnosis of APAP intoxication between October 1997 and October 2002. According to the patient-tailored protocol, which had been used in the ED since 1997, patients with a serum APAP concentration above the limit for possible risk based on a modified Rumack-Matthew nomogram received oral treatment with NAC 140 mg/kg, followed by maintenance doses of 70 mg/kg every 4 hours. NAC treatment was discontinued when the APAP concentration was <10 mg/L and serum aspartate aminotransferase (AST) was <40 IU/L. For the purposes of assessing clinical outcomes, patients were divided into 3 groups based on duration of treatment: the short-course group (/=73 hours). The primary outcome measure was development of hepatotoxicity, defined as a serum AST or alanine aminotransferase concentration >1000 IU/L. RESULTS: Twenty-seven patients were included in the study, 17 in the short-course group, 4 in the intermediate-course group, and 6 in the long-course group. The mean (SD) durations of NAC treatment in the respective groups were 22.1 (5.5) hours, 45.0 (8.2) hours, and 97.3 (33.2) hours. All 6 patients (22%) in the long-course group had hepatotoxicity (peak AST range, 1083-9770 IU/L); their treatment duration ranged from 80 to 164 hours. No patients in the short- or intermediate-course group had evidence of hepatotoxicity. One woman in the long-course group in whom initiation of NAC treatment was delayed by 28 hours died of fulminant hepatic failure. The overall incidence of hepatotoxicity was similar to that in the historical controls. CONCLUSIONS: In this retrospective case series inpatients who received patient-tailored NAC therapy for acute APAP intoxication, the incidence of hepatotoxicity was low and comparable to that in historical controls who received treatment with 1 of 2 fixed-duration regimens. Use of this protocol may have the potential to shorten hospital stays without increasing the risk to patients. However, the sample size was small, and the findings require confirmation in prospective clinical trials.