Overexpressed ski efficiently promotes neurorestoration, increases neuronal regeneration, and reduces astrogliosis after traumatic brain injury.

Traumatic brain injury (TBI) survivors suffer from long-term disability and neuropsychiatric sequelae due to irreparable brain tissue destruction. However, there are still few efficient therapies to promote neurorestoration in damaged brain tissue. This study aimed to investigate whether the pro-oncogenic gene ski can promote neurorestoration after TBI. We established a ski-overexpressing experimental TBI mouse model using adenovirus-mediated overexpression through immediate injection after injury. Hematoxylin-eosin staining, MRI-based 3D lesion volume reconstruction, neurobehavioral tests, and analyses of neuronal regeneration and astrogliosis were used to assess neurorestorative efficiency. The effects of ski overexpression on the proliferation of cultured immature neurons and astrocytes were evaluated using imaging flow cytometry. The Ski protein level increased in the perilesional region at 3 days post injury. ski overexpression further elevated Ski protein levels up to 14 days post injury. Lesion volume was attenuated by approximately 36-55% after ski overexpression, with better neurobehavioral recovery, more newborn immature and mature neurons, and less astrogliosis in the perilesional region. Imaging flow cytometry results showed that ski overexpression elevated the proliferation rate of immature neurons and reduced the proliferation rate of astrocytes. These results show that ski can be considered a novel neurorestoration-related gene that effectively promotes neurorestoration, facilitates neuronal regeneration, and reduces astrogliosis after TBI.

The vascular endothelial growth factor trap aflibercept induces vascular dysfunction and hypertension via attenuation of eNOS/NO signaling in mice.

Aflibercept, as a soluble decoy vascular endothelial growth factor receptor, Which has been used as a first-line monotherapy for cancers. Aflibercept often causes cardiovascular toxicities including hypertension, but the mechanisms underlying aflibercept-induced hypertension remain unknown. In this study we investigated the effect of short-term and long-term administration of aflibercept on blood pressure (BP), vascular function, NO bioavailability, oxidative stress and endothelin 1 (ET-1) in mice and cultured endothelial cells. We showed that injection of a single-dose of aflibercept (18.2, 36.4 mg/kg, iv) rapidly and dose-dependently elevated BP in mice. Aflibercept treatment markedly impaired endothelial-dependent relaxation (EDR) and resulted in NADPH oxidases 1 (NOX1)- and NADPH oxidases 4 (NOX4)-mediated generation of ROS, decreased the activation of protein kinase B (Akt) and endothelial nitric oxide synthase (eNOS) concurrently with a reduction in nitric oxide (NO) production and elevation of ET-1 levels in mouse aortas; these effects were greatly attenuated by supplementation of L-arginine (L-arg, 0.5 or 1.0 g/kg, bid, ig) before aflibercept injection. Similar results were observed in L-arg-pretreated cultured endothelial cells, showing markedly decreased ROS accumulation and AKT/eNOS/NO signaling impairment induced by aflibercept. In order to assess the effects of long-term aflibercept on hypertension and to evaluate the beneficial effects of L-arg supplementation, we administered these two drugs to WT mice for up to 14 days (at an interval of two days). Long-term administration of aflibercept resulted in a sustained increase in BP and a severely impaired EDR, which are associated with NOX1/NOX4-mediated production of ROS, increase in ET-1, inhibition of AKT/eNOS/NO signaling and a decreased expression of cationic amino acid transporter (CAT-1). The effects caused by long-term administration were greatly attenuated by L-arg supplementation in a dose-dependent manner. We conclude that aflibercept leads to vascular dysfunction and hypertension by inhibiting CAT-1/AKT/eNOS/NO signaling, increasing ET-1, and activating NOX1/NOX4-mediated oxidative stress, which can be suppressed by supplementation of L-arg. Therefore, L-arg could be a potential therapeutic agent for aflibercept-induced hypertension.

TRUSS Exacerbates NAFLD Development by Promoting IκBα Degradation in Mice.

There is no effective treatment method for nonalcoholic fatty liver disease (NAFLD), the most common liver disease. The exact mechanism underlying the pathogenesis of NAFLD remains to be elucidated. Here, we report that tumor necrosis factor receptor-associated ubiquitous scaffolding and signaling protein (TRUSS) acts as a positive regulator of NAFLD and in a variety of metabolic disorders. TRUSS expression was increased in the human liver specimens with NAFLD or nonalcoholic steatohepatitis, and in the livers of high-fat diet (HFD)-induced and genetically obese mice. Conditional knockout of TRUSS in hepatocytes significantly ameliorated hepatic steatosis, insulin resistance, glucose intolerance, and inflammatory responses in mice after HFD challenge or in spontaneous obese mice with normal chow feeding. All of these HFD-induced pathological phenotypes were exacerbated in mice overexpressing TRUSS in hepatocytes. We show that TRUSS physically interacts with the inhibitor of nuclear factor κB α (IκBα) and promotes the ubiquitination and degradation of IκBα, which leads to aberrant activation of nuclear factor κB (NF-κB). Overexpressing IκBαS32A/S36A , a phosphorylation-resistant mutant of IκBα, in the hepatocyte-specific TRUSS overexpressing mice almost abolished HFD-induced NAFLD and metabolic disorders. Conclusion: Hepatocyte TRUSS promotes pathological stimuli-induced NAFLD and metabolic disorders, through activation of NF-κB by promoting ubiquitination and degradation of IκBα. Our findings may provide a strategy for the prevention and treatment of NAFLD by targeting TRUSS.

Molecular characterization of Sp110 gene in pigs.

Speckled 110 kDa (Sp110) plays an important role in infectious diseases, as revealed by studies in humans. However, little is known regarding porcine Sp110. To elucidate its potential role in porcine resistance to viral diseases, here, the complete coding sequence of porcine Sp110 gene and its 26 alternatively spliced isoforms were isolated using reverse transcription (RT)-polymerase chain reaction (PCR), and another seven splicing patterns were obtained using a minigene construct. Subcellular distribution of 11 representative isoforms was characterized in PK-15 cells transiently transfected with their respective GFP fusion constructs, and only isoforms (R and V) bearing all functional domains were localized in nucleus, indicating all the other isoforms lose normal functions of Sp110 owing to alternative splicing. Real-time quantitative PCR and competitive RT-PCR showed that both isoforms R and V had similar tissue expression profile, half-life and response to poly(I:C), a synthetic analog of viral double-stranded RNA, while the longer one (isoform R) was transcribed at a higher level. The results indicated that porcine Sp110 has a role in viral infection and that isoform R is the dominant active form. Overall the data provide potential resource for molecular breeding of pig resistant to diseases and contributes to breeding pigs resistant to viral infection.

Characterization of Cardiac Anoctamin1 Ca²âº-Activated Chloride Channels and Functional Role in Ischemia-Induced Arrhythmias.

Anoctamin1 (ANO1) encodes a Ca(2+)-activated chloride (Cl(-)) channel (CaCC) in variety tissues of many species. Whether ANO1 expresses and functions as a CaCC in cardiomyocytes remain unknown. The objective of this study is to characterize the molecular and functional expression of ANO1 in cardiac myocytes and the role of ANO1-encoded CaCCs in ischemia-induced arrhythmias in the heart. Quantitative real-time RT-PCR, immunofluorescence staining assays, and immunohistochemistry identified the molecular expression, location, and distribution of ANO1 in mouse ventricular myocytes (mVMs). Patch-clamp recordings combined with pharmacological analyses found that ANO1 was responsible for a Ca(2+)-activated Cl(-) current (I(Cl.Ca)) in cardiomyocytes. Myocardial ischemia led to a significant increase in the current density of I(Cl.Ca), which was inhibited by a specific ANO1 inhibitor, T16A(inh)-A01, and an antibody targeting at the pore area of ANO1. Moreover, cardiomyocytes isolated from mice with ischemia-induced arrhythmias had an accelerated early phase 1 repolarization of action potentials (APs) and a deeper "spike and dome" compared to control cardiomyocytes from non-ischemia mice. Application of the antibody targeting at ANO1 pore prevented the ischemia-induced early phase 1 repolarization acceleration and caused a much shallower "spike and dome". We conclude that ANO1 encodes CaCC and plays a significant role in the phase 1 repolarization of APs in mVMs. The ischemia-induced increase in ANO1 expression may be responsible for the increased density of I(Cl.Ca) in the ischemic heart and may contribute, at least in part, to ischemia-induced arrhythmias.

Propofol induces endoplasmic reticulum (ER) stress and apoptosis in lung cancer cell H460.

Propofol is one of the most commonly used intravenous anesthetic agents during cancer resection surgery. It can influence proliferation, motility, and invasiveness of cancer cells in vitro and in vivo. However, the role of the propofol in the lung cancer cells remains unclear. In this study, we demonstrated the effects of propofol on the proliferation and the apoptosis of lung cancer cell H460 by using colony formation assay and flow cytometry. Propofol also decreased tumor size and weight in established xenografted tumors. Furthermore, propofol-induced endoplasmic reticulum (ER) stress was determined by Western blot.

Directional transfer of a multiple-allele male sterile line in Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee.

To produce hybrid seeds of Wutacai (Brassica campestris L. ssp. chinensis (L.) Makino var. rosularis Tsen et Lee), a "directional transfer program" was designed to breed the multiple-allele male sterile line of Wutacai. A multiple-allele male sterile line of Naibaicai (Brassica campestris L. ssp. chinensis L., S01) was used as the male sterile resource, and an inbred line of Wutacai (WT01) was used as the target line. Recurrent backcrossing was employed to transfer the male sterility and other botanical traits simultaneously, while the genotype was identifiedthrough test crossing. The male sterility was successfully transferred from S01 to WT01. A new male sterile line, GMS-3, with similar botanical traits to WT01, was bred. Four hybrid combinations were generated with GMS-3 as the female parent. One hybrid (C1) that contained the most desirable traits was developed from the new male sterile line.

The Dirac equation across the horizons of the 5D Myers-Perry geometry: separation of variables, radial asymptotic behaviour and Hamiltonian formalism.

We analytically extend the 5D Myers-Perry metric through the event and Cauchy horizons by defining Eddington-Finkelstein-type coordinates. Then, we use the orthonormal frame formalism to formulate and perform separation of variables on the massive Dirac equation, and analyse the asymptotic behaviour at the horizons and at infinity of the solutions to the radial ordinary differential equation (ODE) thus obtained. Using the essential self-adjointness result of Finster-Röken and Stone's formula, we obtain an integral spectral representation of the Dirac propagator for spinors with low masses and suitably bounded frequency spectra in terms of resolvents of the Dirac Hamiltonian, which can in turn be expressed in terms of Green's functions of the radial ODE.

[Blocking Effects of Foliar Conditioners on Cadmium, Arsenic, and Lead Accumulation in Wheat Grain in Compound-contaminated Farmland].

Heavy metal contamination of soil has become a hot issue of social concern due to its impact on the safety of agricultural products in recent years. Wheat is one of the most dominant staple food crops worldwide and has become a major source of toxic metals in human diets. Foliar application was considered to be a more efficient and economical method of heavy metal remediation. Field experiments were carried out in Cd-, As-, and Pb-contaminated farmland soils. The effects of foliar conditioners on the accumulation of Cd, As, and Pb in wheat grains were investigated after being sprayed with Zn (0.2% ZnSO4), Mg (0.4% MgSO4), and Mn (0.2% MnSO4) separately and in combination. Thus, the effective foliar conditioners were selected to block the accumulation of Cd, As, and Pb in wheat grains grown in combined heavy metal-contaminated farmland in north China. The results showed that, compared with that in the control, the Cd, As, and Pb contents in wheat grains of the Zn+Mg+Mn foliar treatment were significantly decreased by 18.96%, 23.87%, and 51.31%, respectively, and TFgrain/straw decreased by 14.62%, 27.73%, and 47.70%, respectively. Thus, spraying the compound foliar conditioner of Zn+Mg+Mn could effectively reduce heavy metal accumulation in wheat grains through inhibition translocation of those metals from stem leaves to grain. In addition, the results indicated that Cd and As were mainly distributed at the central endosperm (34.08%-37.08%), whereas Pb was primarily distributed at the pericarp and seed coat (27.78%) of the wheat grain. Compared with that in the control, spraying the compound foliar conditioner of Zn+Mg+Mn extremely decreased Cd and As accumulation in the aleurone layer of the wheat grain by 81.10% and 82.24%, respectively. Except for the pericarp, seed coat, and central endosperm layers, the Pb content in each grain layer was dramatically decreased by 42.85% to 91.15%. There was only a significant negative correlation between heavy metal content and Zn content in the aleurone layer (P2) of wheat flour. In summary, the accumulation of Cd, As, and Pb in wheat grains, especially in the aleurone layer, could be effectively reduced by foliar conditioner application at the jointing, booting, and early filling stages of wheat, separately. Furthermore, besides the foliar treatment, removing wheat bran to reduce Cd contamination in wheat grains is highly recommended to ensure the safe production of wheat.

Effects of betamethasone on neuropathic pain in a rat spare nerve injury model.

The aim of the present study was to examine the effect of glucocorticoids on neuropathic pain using a rat spare nerve injury (SNI) model. Eighty rats were treated divided into the following groups: (i) a sham-operated group; (ii) a group subjected to SNI (S); (iii) a group subjected to SNI and administered 4 µg betamethasone intrathecally (D1); and (iv) a group subjected to SNI and administered 1 mg betamethasone at the site of nerve injury (D2). The mechanical withdrawal threshold (MWT) and thermal withdrawal duration (TWD) were measured 1 day before and the 1, 3, 7 and 14 days after SNI. Glial fibrillary acidic protein, glucocorticoid receptor (GR), tumour necrosis factor (TNF)-α and interleukin (IL)-1ß levels in spinal cord tissue were quantified 1, 3, 7 and 14 days after SNI. The MWT was significantly higher in the D2 compared with S group 3-14 days after surgery and compared with the D1 group 7 and 14 days after surgery (P < 0.05). The TWD was significantly lower in the D2 group compared with the S and D2 groups 3-14 days after surgery (P < 0.05). Glial fibrillary acidic protein expression was significantly lower in the D1 and D2 groups compared with the S group 3-14 days after surgery (P < 0.05). Glucocorticoid receptor expression was significantly higher in the D1 group compared with the S and D2 groups after surgery (P < 0.05). Levels of TNF-α and IL-1ß were significantly lower in the D1 and D2 groups compared with the S group at all time points after surgery (P < 0.05). Betamethasone suppressed astrocyte activation and increases in TNF-α and IL-1ß levels in a rat model of neuropathic pain. Local injection of betamethasone resulted in smaller increases in spinal GR expression and more pronounced improvement in pain behaviour compared with intrathecal injection.

[Distribution and Transport of Cadmium and Arsenic in Different Aboveground Parts of Wheat After Flowering].

To investigate the effects of leaves and stems on the accumulation and transport of cadmium(Cd) and arsenic(As) in wheat shoots after flowering, a field experiment was conducted in a typical Cd and As co-contaminated agricultural land to explore the distribution and translocation of Cd and As in the different parts of two wheat cultivars after flowering. The results showed that Cd was mainly distributed in the nodes of two varieties, and the translocation factors of Cd from internode 3 to node 2, from internode 2 to node 1, and from sheath 1 to node 1 were markedly higher than those of other aboveground parts during the grain-filling stage. However, Cd was mainly distributed in the leaves, and the translocation factors of Cd from sheath to leaf and from node 1 to rachis was significantly higher than those of other parts at the mature stage. In addition, the transport capacity of Cd from glume to rachis and from rachis to grain in JM22 was significantly lower than that in SN28, which significantly reduced Cd concentrations in the rachis, glume, and grain of JM22 by 22.3%, 40.8%, and 44.4%, respectively. Meanwhile, As was mainly distributed in the wheat leaves from the grain-filling stage to the mature stage, and As concentrations in the glume and grain of JM22 were 25.8% and 33.3% lower than those of SN28, respectively. Additionally, the translocation factors of As from the sheath to the node were significantly 438% and 190% higher than that from leaf to sheath and from node to internode during the whole grain filling stage and mature stage. Moreover, the translocation factors of As from glumes to grains and from rachis to grains in JM22 were 40.6% and 44.4% lower than that in SN28, respectively. In summary, flag leaf, node 1, and the rachis had regulated Cd transport and accumulation in wheat grains, whereas leaf 3, flag leaf, node 1, the glumes, and the rachis were mainly responsible for As transport and accumulation in wheat grains.

Prognostic Significance of Tumor Mutation Burden among Patients with Non-small Cell Lung Cancer Who Received Platinum-based Adjuvant Chemotherapy: An Exploratory Study.

This study aimed to investigate the prognostic significance of tumor mutation burden (TMB) among patients with non-small cell lung cancer (NSCLC) who received platinum-based adjuvant chemotherapy. Tumor tissue specimens after surgical resection were collected for DNA extraction. Somatic mutation detection and TMB analysis were conducted using next-generation sequencing (NGS). Recurrence status of the patients was assessed in the hospital during the adjuvant chemotherapy period, and long-term survival data of patients were obtained by telephone follow-up. Univariate analysis between TMB status and prognosis was carried out by survival analysis. A retrospective review of 78 patients with non-squamous NSCLC who received platinum-based adjuvant chemotherapy showed a median disease-free survival of 3.6 years and median overall survival (OS) of 5.3 years. NGS analysis exhibited that the most common mutated somatic genes among the 78 patients were tumor suppressor protein p53 (TP53), epidermal growth factor receptor, low-density lipoprotein receptor related protein 1B, DNA methyltransferase 3 alpha and FAT atypical cadherin 3, and their prevalence was 56.4%, 48.7%, 37.2%, 30.7%, and 25.6%, respectively. TMB status was divided into TMB-L (≤ 4.5/Mb) and TMB-H (> 4.5/Mb) based on the median TMB threshold. Relevance of TMB to prognosis suggested that the median OS of patients with TMB-L was significantly longer than that of patients with TMB-H (NR vs. 4.6, P = 0.014). Higher TMB status conferred a worse implication on OS among patients with non-squamous NSCLC who received platinum-based adjuvant chemotherapy.

Inhibition of YAP by lenvatinib in endothelial cells increases blood pressure through ferroptosis.

Lenvatinib, a multitarget tyrosine kinase inhibitor (TKI), increases the incidence of severe hypertension and thus the incidence of cardiovascular complications. Inhibition of ferroptosis, a newly recognized type of cell death, alleviates endothelial dysfunction. Here, we report that lenvatinib-induced hypertension is associated with ferroptosis of endothelial cells. RNA sequencing (RNA-seq) showed that lenvatinib led to ferroptosis of endothelial cells and that administration of mouse with ferrostatin-1 (Fer-1), a specific ferroptosis inhibitor, dramatically ameliorated lenvatinib-induced hypertension and reversed lenvatinib-induced impairment of endothelium-dependent relaxation (EDR). Furthermore, lenvatinib significantly reduced glutathione peroxidase 4 (GPX4) expressions in the mouse aorta and human umbilical vein endothelial cells (HUVECs) and increased lipid peroxidation, lactate dehydrogenase (LDH) release, and malondialdehyde (MDA) levels in HUVECs. Immunofluorescence and Western blotting showed that lenvatinib significantly reduced Yes-associated protein (YAP) nuclear translocation but not cytoplasmic YAP expression in HUVECs. The data, generated from both in vivo and in vitro, showed that lenvatinib reduced total YAP (t-YAP) expression and increased the phosphorylation of YAP at both Ser127 and Ser397, without affecting YAP mRNA levels in HUVECs. XMU-MP-1 mediated YAP activation or YAP overexpression effectively attenuated the lenvatinib-induced decrease in GPX4 expression and increases in LDH release and MDA levels. In addition, overexpression of YAP in HUVECs ameliorated lenvatinib-induced decrease in the mRNA and protein levels of spermidine/spermine N (1)-acetyltransferase-1 (SAT1), heme oxygenase-1 (HO-1), and ferritin heavy chain 1 (FTH1). Taken together, our data suggest that lenvatinib-induced inhibition of YAP led to ferroptosis of endothelial cells and subsequently resulted in vascular dysfunction and hypertension.

Synthesis of α,ß-unsaturated γ-amino esters with a quaternary center by ruthenium-catalyzed codimerization of N-acetyl α-arylenamines and acrylates.

Ruthenium-catalyzed highly selective codimerization of N-acetyl α-arylenamines with ethyl acrylates is reported. This codimerization reaction provides a new efficient method for the synthesis of α,ß-unsaturated γ-amino esters with a quaternary center.

Sustained-release oxycodone tablets for moderate to severe painful diabetic peripheral neuropathy: a multicenter, open-labeled, postmarketing clinical observation.

OBJECTIVE: To evaluate the efficacy and safety of sustained-release (SR) oxycodone tablets in the treatment of moderate to severe painful diabetic peripheral neuropathy (DPN). Design. This was a multicenter, randomized, open-labeled study. SETTING: This study was completed in 12 hospitals in China. PATIENTS: A total of 80 Chinese patients undergoing moderate to severe painful DPN. INTERVENTIONS: An initial dose of 10mg is recommended to be taken orally every 12 hours. Dose titration was done appropriately according to pain intensity and adverse reactions. OUTCOME MEASURES: Data record included days, dosage, analgesic efficacy, quality of sleep, adverse events, and combination therapy when patients were treated with SR oxycodone tablets. The continuous observation period was 6 weeks. RESULTS: After medication for 1 week, pain was significantly (P<0.01) relieved from 6.8±1.4 to 2.8±1.6. Onset time was within 45 minutes in nearly 60% of the patients, and within 1 hour in nearly 95% of that ones. More than 90% of the patients achieved stable analgesic dose within 3 days. After using SR oxycodone tablets for 1 week, sleep quality was significantly (P<0.01) improved. In week 1, the average dose of SR oxycodone tablets was 16.63±7.79mg. The average daily dose of most patients was about 20mg after 2 weeks. In all the enrolled patients, 38 (47.5%) had adverse reactions. No serious adverse reactions took place. CONCLUSION: The results of this clinical observation further elaborated the efficacy and safety of SR oxycodone tablets in the treatment of moderate to severe painful diabetic peripheral neuropathy in China.

Aldosterone-stimulated endothelial epithelial sodium channel (EnNaC) plays a role in cold exposure-induced hypertension in rats.

Background: Previous studies have demonstrated that activated endothelial epithelial sodium channel (EnNaC) impairs vasodilatation, which contributes to salt-sensitive hypertension. Here, we investigate whether mesenteric artery (MA) EnNaC is involved in cold exposure-induced hypertension (CIH) and identify the underlying mechanisms in SD rats. Methods: One group of rats was housed at room temperature and served as control. Three groups of rats were kept in a 4°C cold incubator for 10 h/day; among which two groups were administrated with either benzamil (EnNaC blocker) or eplerenone (mineralocorticoid receptor antagonist, MR). Blood pressure (BP), vasodilatation, and endothelial function were measured with tail-cuff plethysmography, isometric myograph, and Total Nitric Oxide (NO) Assay kit, respectively. A cell-attached patch-clamp technique, in split-open MA, was used to determine the role of EnNaC in CIH rats. Furthermore, the plasma aldosterone levels were detected using an ELISA kit; and Western blot analysis was used to examine the relative expression levels of Sgk1 and Nedd4-2 proteins in the MA of SD rats. Results: We demonstrated that cold exposure increased BP, impaired vasodilatation, and caused endothelial dysfunction in rats. The activity of EnNaC significantly increased, concomitant with an increased level of plasma aldosterone and activation of Sgk1/Nedd4-2 signaling. Importantly, CIH was inhibited by either eplerenone or benzamil. It appeared that cold-induced decrease in NO production and impairment of endothelium-dependent relaxation (EDR) were significantly ameliorated by either eplerenone or benzamil in MA of CIH rats. Moreover, treatment of MAs with aldosterone resulted in an activation of EnNaC, a reduction of NO, and an impairment of EDR, which were significantly inhibited by either eplerenone or GSK650394 (Sgk1 inhibitor) or benzamil. Conclusion: Activation of EnNaC contributes to CIH; we suggest that pharmacological inhibition of the MR/Sgk1/Nedd4-2/EnNaC axis may be a potential therapeutic strategy for CIH.

The functional expression of extracellular calcium-sensing receptor in rat pulmonary artery smooth muscle cells.

BACKGROUND: The extracellular calcium-sensing receptor (CaSR) belongs to family C of the G protein coupled receptors. Whether the CaSR is expressed in the pulmonary artery (PA) is unknown. METHODS: The expression and distribution of CaSR were detected by RT-PCR, Western blotting and immunofluorescence. PA tension was detected by the pulmonary arterial ring technique, and the intracellular calcium concentration ([Ca2+]i) was detected by a laser-scanning confocal microscope. RESULTS: The expressions of CaSR mRNA and protein were found in both rat pulmonary artery smooth muscle cells (PASMCs) and PAs. Increased levels of [Ca2+]o (extracellular calcium concentration) or Gd3+ (an agonist of CaSR) induced an increase of [Ca2+]i and PAs constriction in a concentration-dependent manner. In addition, the above-mentioned effects of Ca2+ and Gd3+ were inhibited by U73122 (specific inhibitor of PLC), 2-APB (specific antagonist of IP3 receptor), and thapsigargin (blocker of sarcoplasmic reticulum calcium ATPase). CONCLUSIONS: CaSR is expressed in rat PASMCs, and is involved in regulation of PA tension by increasing [Ca2+]i through G-PLC-IP3 pathway.

Role of the epithelial sodium channel in salt-sensitive hypertension.

The epithelial sodium channel (ENaC) is a heteromeric channel composed of three similar but distinct subunits, α, ß and γ. This channel is an end-effector in the rennin-angiotensin-aldosterone system and resides in the apical plasma membrane of the renal cortical collecting ducts, where reabsorption of Na(+) through ENaC is the final renal adjustment step for Na(+) balance. Because of its regulation and function, the ENaC plays a critical role in modulating the homeostasis of Na(+) and thus chronic blood pressure. The development of most forms of hypertension requires an increase in Na(+) and water retention. The role of ENaC in developing high blood pressure is exemplified in the gain-of-function mutations in ENaC that cause Liddle's syndrome, a severe but rare form of inheritable hypertension. The evidence obtained from studies using animal models and in human patients indicates that improper Na(+) retention by the kidney elevates blood pressure and induces salt-sensitive hypertension.

Streptococcal pneumonia-associated hemolytic uremic syndrome treated by T-antibody-negative plasma exchange in children: Two case reports.

BACKGROUND: The occurrence of Streptococcus pneumoniae-associated hemolytic uremic syndrome (SP-HUS) is increasing. Thomsen-Friedenreich antigen activation is highly involved in the pathogenesis of SP-HUS, and T-antibody-negative plasma exchange (PE) may be effective in the treatment of severe cases of SP-HUS. CASE SUMMARY: We retrospectively reviewed two pediatric patients with SP-HUS. Both clinical features and laboratory examination results of the children were described. T-antibody-negative PE was performed in both cases. Both children made a full recovery after repeated PE and remained well at a 2 year follow-up. CONCLUSION: Streptococcal pneumonia continues to be an uncommon but important cause of HUS. The successful treatment of the presented cases suggests that T-antibody-negative PE may benefit patients with SP-HUS.

Cholesterol Stimulates the Transient Receptor Potential Melastatin 4 Channel in mpkCCDc14 Cells.

We have shown that cholesterol regulates the activity of ion channels in mouse cortical collecting duct (CCD) mpkCCDc14 cells and that the transient receptor potential melastatin 4 (TRPM4) channel is expressed in these cells. However, whether TRPM4 channel is regulated by cholesterol remains unclear. Here, we performed inside-out patch-clamp experiments and found that inhibition of cholesterol biosynthesis by lovastatin significantly decreased, whereas enrichment of cholesterol with exogenous cholesterol significantly increased, TRPM4 channel open probability (Po) by regulating its sensitivity to Ca2+ in mpkCCDc14 cells. In addition, inside-out patch-clamp data show that acute depletion of cholesterol in the membrane inner leaflet by methyl-ß-cyclodextrin (MßCD) significantly reduced TRPM4 Po, which was reversed by exogenous cholesterol. Moreover, immunofluorescence microscopy, Western blot, cell-surface biotinylation, and patch clamp analysis show that neither inhibition of intracellular cholesterol biosynthesis with lovastatin nor application of exogenous cholesterol had effect on TRPM4 channel protein abundance in the plasma membrane of mpkCCDc14 cells. Sucrose density gradient centrifugation studies demonstrate that TRPM4 was mainly located in cholesterol-rich lipid rafts. Lipid-protein overlay experiments show that TRPM4 directly interacted with several anionic phospholipids, including PI(4,5)P2. Depletion of PI(4,5)P2 with either wortmannin or PGE2 abrogated the stimulatory effects of exogenous cholesterol on TRPM4 activity, whereas exogenous PI(4,5)P2 (diC8-PI(4,5)P2, a water-soluble analog) increased the effects. These results suggest that cholesterol stimulates TRPM4 via a PI(4,5)P2-dependent mechanism.