Adenosine receptor A2b confers ovarian cancer survival and PARP inhibitor resistance through IL-6-STAT3 signalling.

Ovarian cancer is the deadliest gynecologic cancer worldwide, and the therapeutic options are limited. PARP inhibitor (PARPi) represents an effective therapeutic strategy and has been approved for maintenance therapy. However, the intrinsic or acquired resistance to PARPi becomes a big challenge. To investigate the mechanisms for PARPi resistance, we analysed public databases and established Olaparib-resistant ovarian cancer cells for exploration. Our results showed that the inflammatory pathway and adenosine receptor A2b (Adora2b/A2B ) expression were significantly increased in Olaparib-resistant cells. A2B was highly expressed in recurrent ovarian tumours and negatively correlated with the clinical outcomes in cancer patients. Olaparib treatment enhanced A2B expression through NF-κB activation. The elevated A2B contributed to Olaparib resistance by sensing adenosine signal and promoting tumour cell survival, growth and migration via IL-6-STAT3 signalling. Therefore, inhibition of A2B -IL-6-STAT3 axis could overcome Olaparib resistance and synergize with Olaparib to reduce cancer cell growth and lead to cell death. Our findings reveal a critical role of A2B signalling in mediating PARPi resistance independent of DNA damage repair, providing insights into developing novel therapies in ovarian cancers.

Localization Approach for Underwater Sensors in the Magnetic Silencing Facility Based on Magnetic Field Gradients.

Localization of the underwater magnetic sensor arrays plays a pivotal role in the magnetic silencing facility. A localization approach is proposed for underwater sensors based on the optimization of magnetic field gradients in the inverse problem of localization. In the localization system, a solenoid coil carrying direct current serves as the magnetic source. By measuring the magnetic field generated by the magnetic source in different positions, an objective function is established. The position vector of the sensor is determined by a novel multi-swarm particle swarm optimization with dynamic learning strategy. Without the optimization of the magnetic source's positions, the sensors' positions, especially in the z-axis direction, struggle to meet the requested localization. A strategy is proposed to optimize the positions of the magnetic source based on magnetic field gradients in the three directions of x, y and z axes. Compared with the former method, the model experiments show that the proposed method could achieve a 10 cm location error for the position type 2 sensor and meet the request of localization.

Metabolomics analysis of serum in pediatric nephrotic syndrome based on targeted and non-targeted platforms.

BACKGROUND AND AIMS: Nephrotic syndrome (NS) is a common pediatric urinary system disease. The aim in this work was to investigate the changes in pediatric NS-related metabolites through serum metabolomics, and explore the new potential metabolites and differential metabolic pathways. METHODS: Serum samples from 40 pediatric patients with nephrotic syndrome and 40 healthy controls were collected. The targeted and non-targeted metabolomics analyses were performed to determine the metabolic changes in pediatric NS. Based on multivariate statistical analysis and the regression model, the serum potential metabolites were screened and different metabolic pathways were explored. RESULTS: 39 differential metabolites in pediatric NS were obtained based on the metabolomics analysis. 12 differential metabolites (serine, C18: 2 (EFA), C18: 2 (FFA), Isonuatigenin 3- [rhamnosyl- (1- > 2) -glucoside], C18: 4 (EFA), C18: 4 (FFA), caprylic acid, citric acid, methylmalonic acid, caproic acid, canavalioside and uroporphyrin were identified to establish the diagnostic model for pediatric NS. Five metabolic pathways including TCA cycle, amino acid metabolism, bile acid biosynthesis, linoleate metabolism and glyoxylate and dicarboxylate metabolism were the key differential metabolic pathways. CONCLUSION: These data elucidated the metabolic alterations associated with pediatric NS and suggested a new diagnosis model for monitoring pediatric NS. The current study provides the useful information to bridge the gaps in our understanding of the metabolic alterations associated with pediatric NS and might facilitate the characterization of pediatric NS patients by performing serum metabolomics.

m6A-seq analysis of microRNAs reveals that the N6-methyladenosine modification of miR-21-5p affects its target expression.

In eukaryotes, N6-methyladenosine (m6A) is one of the most abundant modifications on RNAs, and it plays important roles in many biological processes and diseases such as cancer. While most m6A researches focus on message RNAs and long non-coding RNAs, recent studies have reported the presence of m6A in small RNAs. Nevertheless, current knowledge about m6A prevalence in mature microRNAs (miRNA) is extremely limited and the functional significance of m6A methylation in miRNAs remains to be elucidated. Here, we demonstrated cell-specific m6A profiles of miRNAs in A549 human non-small cell lung cancer (NSCLC) cells and HEK293A cells by using miRNA m6A immunoprecipitation sequencing and constructed the consensus motif in m6A-enriched miRNAs de novo. We found that miR-21-5p, an oncogenic miRNA, showed the highest m6A enrichment in NSCLC cells. Depletion of the demethylase ALKBH5 did not change the expression level of miR-21-5p, but altered the m6A abundance of miR-21-5p, thereby changing the expression levels of its target gene. We further synthesized m6A modified miR-21-5p mimics in vitro and demonstrated that in NSCLC cells, m6A marks in mature miR-21-5p could directly affect its silencing potency towards target genes, which finally impaired its promotion to proliferation and motility. Together, our findings reveal the landscape of m6A modification in mature miRNAs, and provide the first evidence that it may contribute to the mRNA responses to cancer-related miRNAs.

Liquid marbles from soot films.

Soot films are the most easily available superhydrophobic surfaces. However, their cohesive forces are very weak such that they have been considered not suitable for direct use. Here we show that the seemingly undesirable mechanical weakness is actually an important property which allows a soot film to work as a superhydrophobic platform and tool, producing liquid marbles with fascinating properties and performances. A soot film is weak enough to lose component carbon nanoparticles (CNPs) on contact with water, but can adhere to a substrate stably on overturning or shaking the substrate. On this basis, we demonstrate that a liquid marble consisting of a liquid core and a CNP shell can be obtained by either rolling or an imprinting process. In addition, it is found that large-volume liquid puddles are easy to produce and manipulate with soot films by arbitrary shaking and pouring operations, without worrying about particles flying off that would occur in conventional powder-based liquid puddle production. The multifunctionality of CNPs endows soot liquid marbles/puddles with great potential in light shielding, electrical conduction, etc. This study reveals a direct application of soot films' superhydrophobicity, provides an alternative route for liquid marble production, and highlights the concept of disadvantage reversion.

Cystamine slows but not inverses the progression of monocrotaline-induced pulmonary arterial hypertension in rats.

Tissue transglutaminase (TG2) plays an important role in pulmonary arterial hypertension (PAH). Previous research indicate that TG2 and protein serotonylation catalyzed by TG2 are upregulated in PAH. Serotonin transporter inhibitor fluoxetine ameliorates PAH via inhibition of protein serotonylation. It is still unknown whether PAH is inhibited through direct inhibition of TG2. Therefore, the present study aimed to investigate the effects of TG2 inhibitor cystamine on monocrotaline-induced PAH in rats. Rats were treated with monocrotaline (60 mg·kg-1, i.p.) in combination with or without cystamine (20, 40 mg·kg-1·day-1, p.o.). The results showed that compared with monocrotaline alone, combination of monocrotaline with cystamine (40 mg·kg-1·day-1, p.o.) relieved right ventricle hypertrophy, inhibited pulmonary arteriolar remodeling, and downregulated protein expression of TG2, phosphorylated protein kinase B (Akt), and extracellular regulated protein kinase (ERK) at day 21. However, except for TG2 expression, these changes were not significantly inhibited by cystamine at day 35. In addition, cystamine dose-dependently enhanced the survival rate of rats injected with monocrotaline at day 35. The findings suggest that cystamine slows but not reverses monocrotaline-induced PAH in rats, which was largely associated with the inhibition of TG2 protein expression and Akt and ERK activation.

A prospective randomized trial comparing anterior cervical discectomy and fusion versus plate-only open-door laminoplasty for the treatment of spinal stenosis in degenerative diseases.

OBJECTIVE: For three or more involved cervical levels, there is a debate over which approach yields the best outcomes for the treatment of multilevel cervical degenerative disease. Our objective is to compare the radiological and clinical outcomes of two treatments for multilevel cervical degenerative disease: anterior cervical discectomy and fusion (ACDF) versus plate-only open-door laminoplasty (laminoplasty). METHODS: Patients were randomized on a 1:1 randomization schedule with 17 patients in the ACDF group and 17 patients in the laminoplasty group. Clinical outcomes were assessed by a visual analog scale (VAS), Japanese Orthopedic Association (JOA) scores, operative time, blood loss, rates of complications, drainage volume, discharge days after surgery, and complications. The cervical spine curvature index (CI) and range of motion (ROM) were assessed with radiographs. RESULTS: The mean VAS score, the mean JOA score, and the rate of complications did not differ significantly between groups. The laminoplasty group had greater blood loss, a longer operative time, more drainage volume, and a longer hospital stay than the ACDF group. There were no significant differences in the CI and ROM between the two groups at baseline and at each follow-up time point. ROM in both groups decreased significantly after surgery. CONCLUSIONS: Both ACDF and laminoplasty are effective and safe treatments for multilevel cervical degenerative disease. ACDF causes fewer traumas than laminoplasty.

Hyperoside exerts anti-inflammatory and anti-arthritic effects in LPS-stimulated human fibroblast-like synoviocytes in vitro and in mice with collagen-induced arthritis.

AIM: Hyperoside is a flavonol glycoside mainly found in plants of the genera Hypericum and Crataegus, which has shown anti-oxidant, anti-cancer and anti-inflammatory activities. In this study, we investigated the effects of hyperoside on human rheumatoid fibroblast-like synoviocytes (FLSs) in vitro and on mouse collagen-induced arthritis (CIA) in vivo. METHODS: FLSs were isolated from primary synovial tissues obtained from rheumatoid arthritis (RA) patients and exposed to LPS (1 µg/mL). Cell viability and proliferation were measured with MTT and BrdU assay. Cell migration was assessed using wound-healing assay and Transwell assay. DNA binding of NF-κB was measured using a TransAM-NFkappaB kit. The localization of p65 subunit was detected with immunocytochemistry. CIA was induced in mice by primary immunization with Bovine Type II collagen (CII) emulsified in CFA, followed by a booster injection 3 weeks later. The arthritic mice were treated with hyperoside (25, 50 mg·kg(-1)·d(-1), ip) for 3 weeks, and the joint tissues were harvested for histological analysis. RESULTS: Hyperoside (10, 50, 100 µmol/L) dose-dependently inhibited LPS-induced proliferation and migration of human RA FLSs in vitro. Furthermore, hyperoside decreased LPS-stimulated production of TNF-α, IL-6, IL-1 and MMP-9 in the cells. Moreover, hyperoside inhibited LPS-induced phosphorylation of p65 and IκBα, and suppressed LPS-induced nuclear translocation of p65 and DNA biding of NF-κB in the cells. Three-week administration of hyperoside significantly decreased the clinical scores, and alleviated synovial hyperplasia, inflammatory cell infiltration and cartilage damage in mice with CIA. CONCLUSION: Hyperoside inhibits LPS-induced proliferation, migration and inflammatory responses in human RA FLSs in vitro by suppressing activation of the NF-κB signaling pathway, which contributes to the therapeutic effects observed in mice with CIA.

Atorvastatin prevents amyloid-ß peptide oligomer-induced synaptotoxicity and memory dysfunction in rats through a p38 MAPK-dependent pathway.

AIM: To investigate whether atorvastatin treatment could prevent Aß1-42 oligomer (AßO)-induced synaptotoxicity and memory dysfunction in rats, and to elucidate the mechanisms involved in the neuroprotective actions of atorvastatin. METHODS: SD rats were injected with AßOs (5 nmol, icv). The rats were administrated with atorvastatin (10 mg·kg(-1)·d(-1), po) for 2 consecutive weeks (the first dose was given 5 d before AßOs injection). The memory impairments were evaluated with Morris water maze task. The expression of inflammatory cytokines in the hippocampus was determined using ELISA assays. The levels of PSD-95 and p38MAPK proteins in rat hippocampus were evaluated using Western blot analysis. For in vitro experiments, cultured rat hippocampal neurons were treated with AßOs (50 nmol/L) for 48 h. The expression of MAP-2 and synaptophysin in the neurons was detected with immunofluorescence. RESULTS: The AßO-treated rats displayed severe memory impairments in Morris water maze tests, and markedly reduced levels of synaptic proteins synaptophysin and PSD-95, increased levels of inflammatory cytokines (IL-1ß, IL-6 and TNF-α) and p38MAPK activation in the hippocampus. All these effects were prevented or substantially attenuated by atorvastatin administration. Pretreatment of cultured hippocampal neurons with atorvastatin (1 and 5 µmol/L) concentration-dependently attenuated the AßO-induced synaptotoxicity, including the loss of dendritic marker MAP-2, and synaptic proteins synaptophysin and PSD-95. Pretreatment of the cultured hippocampal neurons with the p38MAPK inhibitor SB203580 (5 µmol/L) blocked the AßO-induced loss of synaptophysin and PSD-95. CONCLUSION: Atorvastatin prevents AßO-induced synaptotoxicity and memory dysfunction through a p38MAPK-dependent pathway.

The scientometric characteristics of cheilitis researched by multidisciplinary specialists: A comparative study.

Background/purpose: Cheilitis is a relatively common lip disease with many etiologies and causes including concomitant mucocutaneous or systemic diseases, which needs multidisciplinary communication. The purpose of this study was to compare the scientometric characteristics of cheilitis publications by multidisciplinary specialists. Materials and methods: All the papers on cheilitis were comprehensively retrieved from the Scopus database, and divided into three groups (dermatologists, stomatologists, and other scholars). Results: There were 478 and 241 papers on cheilitis published by dermatologists and stomatologists, respectively. The total citation count was 5838 and the h index was 36 for cheilitis publications by dermatologists, and the total count was 2983 and the h index was 27 for cheilitis publications by stomatologists. Interestingly, we observed that dermatologists preferentially concerned contact cheilitis/dermatitis and plasma cell cheilitis, while stomatologists preferentially concerned cheilitis-related lip neoplasms including squamous cell carcinoma, dysplasia, and precancerous conditions. The most common disorder researched by both dermatologists and stomatologists was actinic cheilitis. The keywords such as patch test, cosmetic, edema, drug efficacy, toothpaste, lipstick, allergens, and granulomatous inflammation were common in dermatologists' publications; while the keywords such as protein expression, metabolism, risk factor, prevalence, malignant transformation, and carcinogenesis were common in stomatologists' publications. Conclusion: This study for the first time reported the scientometric characteristics of cheilitis as an interdisciplinary disease researched by specialists. It highlights that cheilitis-related specialists through reciprocal collaboration and communication will improve the patients' outcomes.

L.acidophilus HSCC LA042 and HKL suspension ameliorate DSS-induced ulcerative colitis in mice by improving the intestinal barrier inhibiting the NLRP3 inflammasome and pathogenic bacteria.

Ulcerative Colitis(UC) is a chronic intestinal inflammation affecting the intestines, yet its underlying causes remain unclear. In recent decades, the global prevalence of UC has been on the rise, leading to an increasing demand for therapeutic drugs with minimal side effects. Huan Kui Le (HKL), a traditional Chinese medicine compound, has demonstrated promising efficacy when combined with Lactobacillus acidophilus (Lac.) for UC intervention. However, the precise therapeutic mechanism of this combination remains unknown. The study focused on understanding the mechanisms of UC by examining the effects of Lac. and HKL (LH) treatment. The outcomes discovered that the disruption of gut microbiota, triggered by the activation of the NLRP3 inflammasome, plays a crucial role in UC development. This disruption exacerbates UC symptoms by causing disturbances in inflammatory cytokines and mucosal permeability. We investigated the dynamic changes following the application of this treatment using 16S rRNA sequencing, HE, WB, IHC, and ELISA. Compared with the UC group, LH treatment reduced colon pathological injury, improved colon length, and decreased IL-1 ß serum levels. Furthermore, it restored the expression of TJs and preserved mucosal barrier integrity. LH treatment also mitigated colon injury by attenuating the expression of pyroptosis-related genes and proteins, such as NLRP3 and Caspase-1. Additionally, LH treatment altered the gut microbiota's microecology, characterized by a reduction in pathogenic bacteria abundance like Escherichia-shigella and an increase in beneficial bacteria abundance like Akkermansia and Erysipelatoclostridium. Overall, our findings indicate that LH therapy may be associated with intestinal barrier repair, inflammasome inhibition, and gut microbiota regulation, suggesting its potential as a UC treatment.

The ribosome-related protein, SBDS, is critical for normal erythropoiesis.

Although anemia is common in Shwachman- Diamond syndrome (SDS), the underlying mechanism remains unclear. We asked whether SBDS, which is mutated in most SDS patients, is critical for erythroid development. We found that SBDS expression is high early during erythroid differentiation. Inhibition of SBDS in CD34(+) hematopoietic stem cells and early progenitors (HSC/Ps) and K562 cells led to slow cell expansion during erythroid differentiation. Induction of erythroid differentiation resulted in markedly accelerated apoptosis in the knockdown cells; however, proliferation was only mildly reduced. The percentage of cells entering differentiation was not reduced. Differentiation also increased the oxidative stress in SBDS-knockdown K562 cells, and antioxidants enhanced the expansion capability of differentiating SBDS-knockdown K562 cells and colony production of SDS patient HSC/Ps. Erythroid differentiation also resulted in reduction of all ribosomal subunits and global translation. Furthermore, stimulation of global translation with leucine improved the erythroid cell expansion of SBDS-knockdown cells and colony production of SDS patient HSC/Ps. Leucine did not reduce the oxidative stress in SBDS-deficient K562 cells. These results demonstrate that SBDS is critical for normal erythropoiesis. Erythropoietic failure caused by SBDS deficiency is at least in part related to elevated ROS levels and translation insufficiency because antioxidants and leucine improved cell expansion.

Effects of Rehabilitation Therapy at Different Intervention Times on Daily Living Activity and Motor Function in Patients with Traumatic Spinal Cord Injury.

Objectives: We investigated the impact of traumatic spinal cord injury (TSCI) on daily living activities and motor function of TSCI patients. Methods: A total of 88 TSCI patients were randomly divided into Group A (N=44) and Group B (N=44). Group A received rehabilitation treatment 7 days after the stabilization of vital signs, and Group B received rehabilitation treatment 30 days after hospitalization. Results: The compliance rate of Group A (93.18%) was higher than that of Group B (72.73%) (χ 2 =6.510, p<.05); The scores of American Spinal Injury Association (ASIA) and Activities of Daily Living (ADL) in Group A were higher than those in Group B. The self-rating score of anxiety and depression was lower than that of Group B (p<.05). Conclusion: For the rehabilitation treatment of TSCI patients, it is better to choose the intervention after the vital signs are stable to improve patients' ability for daily living activities and motor function.

Fluoxetine inhibits monocrotaline-induced pulmonary arterial remodeling involved in inhibition of RhoA-Rho kinase and Akt signalling pathways in rats.

Activation of the small GTPase Ras homolog gene family member A (RhoA) and Rho-associated kinase (ROCK) are important in the pathogenesis of pulmonary arterial hypertension (PAH). Selective serotonin reuptake inhibitors inhibit activation of RhoA and ROCK in vitro, and ameliorate PAH and pulmonary arterial remodeling in vivo. However, little is known about whether the RhoA-ROCK signalling pathway is involved in the treatment of PAH with fluoxetine in vivo. The aim of the present study was to investigate the involvement of the RhoA-ROCK signalling pathway in the protective effect of the selective serotonin reuptake inhibitor fluoxetine against monocrotaline (MCT)-induced pulmonary arterial remodeling. MCT was applied to establish PAH in male Wistar rats. Fluoxetine was administered by gastric gavage once a day for 21 d. The results showed that MCT induced pulmonary arterial remodeling, raised the serotonylation and membrane translocation of RhoA in the lungs, and increased serotonin transporter (5-HTT), RhoA, and ROCK2 expression, and extracellular signal-regulated kinase (ERK) and Akt phosphorylation in the pulmonary arteries and the lungs. Fluoxetine markedly inhibited these MCT-induced changes. The findings suggest that fluoxetine inhibits MCT-induced pulmonary arterial remodeling in rats by inhibition of the RhoA-ROCK and Akt signalling pathways.

Controlled release of ciliary neurotrophic factor from bioactive nerve grafts promotes nerve regeneration in rats with facial nerve injuries.

It is critical to repair severed facial nerves, as lack of treatment may cause long-term motor and sensory impairments. Ciliary neurotrophic factor (CNTF) plays an important role in terms of enhancing nerve axon regrowth and maturation during peripheral nerve regeneration after injury. However, simple application of CNTF to the transected nerve site does not afford functional recovery, because it is rapidly flushed away by bodily fluids. The aim of the present study was the construction of a new, bioactive composite nerve graft facilitating persistent CNTF delivery to aid the reconstruction of facial nerve defects. The in vitro study showed that the bioactive nerve graft generated sustainable CNTF release for more than 25 days. The bioactive nerve graft was then transplanted into the injury sites of rat facial nerves. At 6 and 12 weeks post-transplantation, functional and histological analyses showed that the bioactive nerve graft featuring immobilized CNTF significantly enhanced nerve regeneration in terms of both axonal outgrowth and Schwann cell proliferation in the rat facial nerve gap model, compared to a collagen tube with adsorbed CNTF that initially released high levels of CNTF. The bioactive nerve graft may serve as novel, controlled bioactive release therapy for facial nerve regeneration.

Argonaute-integrated isothermal amplification for rapid, portable, multiplex detection of SARS-CoV-2 and influenza viruses.

Isothermal amplification methods are a promising trend in virus detection because of their superiority in rapidity and sensitivity. However, the generation of false positives and limited multiplexity are major bottlenecks that must be addressed. In this study, we developed a multiplex Argonaute (Ago)-based nucleic acid detection system (MULAN) that integrates rapid isothermal amplification with the multiplex inclusiveness of a single Ago for simultaneous detection of multiple targets such as SARS-CoV-2 and influenza viruses. Owing to its high specificity, MULAN can distinguish targets at a single-base resolution for mutant genotyping. Moreover, MULAN also supports portable and visible devices with a limit of detection of five copies per reaction. Validated by SARS-CoV-2 pseudoviruses and clinical samples of influenza viruses, MULAN showed 100% agreement with quantitative reverse-transcription PCR. These results demonstrated that MULAN has great potential to facilitate reliable, easy, and quick point-of-care diagnosis for promoting the control of infectious diseases.

Development of a high specificity typing method for the detection of herpes simplex virus.

Herpes disease is caused by Herpes simplex virus (HSV). It has become one of the global health problems. This paper reports a method for HSV type testing. First specific primers sequence for HSV-1 and HSV-2 were selected, designed, and synthesized. Then, these amplification products were proved by sequencing and analysis. Lastly, we optimized the reaction system and PCR reaction program by orthogonal design and sensitivity testing. Results showed that the lowest concentration in HSV-type testing is about 6.67 × 106 copies/ml. Moreover, the specificity of detection was very high. So, this method has very great potentials for HSV type testing in clinical practice.

Fluoxetine inhibited extracellular matrix of pulmonary artery and inflammation of lungs in monocrotaline-treated rats.

AIM: To investigate the effects of the selective serotonin reuptake inhibitor (SSRI) fluoxetine on extracellular matrix (ECM) remodeling of the pulmonary artery and inflammation of the lungs in pulmonary arterial hypertension (PAH) induced by monocrotaline in rats. METHODS: MCT-induced chronic PAH was established in Wistar rats. After treatment with fluoxetine for 3 weeks, pulmonary hemodynamic measurement and morphological investigation of lung tissues were undertaken. The main components of the ECM, elastin and collagen, were detected using Van Gieson stain and Orcein stain, respectively, or using Victoria-ponceau's double stain. The ECM proteolytic enzymes matrix metalloproteinase (MMP)-2 and MMP-9, and the tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2, were detected by Western blot. Inflammation of lung tissue was assayed using lung morphology and inflammatory cytokine expression. RESULTS: Fluoxetine (2 and 10 mg/kg) significantly inhibited MCT-induced PAH, attenuated pulmonary arterial muscularization and ECM remodeling, and decreased MMP/TIMP expression. Fluoxetine also suppressed inflammatory responses in lung tissue and inhibited the expression of the inflammatory cytokines interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), monocyte chemotactic protein (MCP-1) and intercellular adhesion molecule-1 (ICAM-1). CONCLUSION: Fluoxetine inhibited MCT-induced ECM remodeling of the pulmonary artery and inflammation of lung tissue. These effects were related to its inhibition on MMPs/TIMPs and cytokine productions.

Downregulation of osteopontin is associated with fluoxetine amelioration of monocrotaline-induced pulmonary inflammation and vascular remodelling.

1. Osteopontin (OPN) has emerged as a key factor in inflammatory activation and cardiovascular remodelling. The aim of the present study was to investigate the involvement of OPN in fluoxetine amelioration of monocrotaline (MCT)-induced pulmonary inflammation and vascular remodelling in rats. 2. Wistar rats were divided into control, MCT and two fluoxetine-treated groups. Pulmonary arterial hypertension (PAH) was induced by a single injection of MCT (60 mg/kg, i.p.). Fluoxetine (2 and 10 mg/kg) was administered via the intragastric route once a day for 21 days. On Day 22, pulmonary haemodynamic measurements were undertaken, followed by ELISA, western blotting and immunohistochemistry. 3. Monocrotaline caused pulmonary inflammation and vascular remodelling and significantly enhanced OPN expression in the plasma, lungs and pulmonary arteries. Fluoxetine decreased pulmonary arterial pressure and ameliorated pulmonary inflammation and pulmonary vascular remodelling. At 10 mg/kg, fluoxetine significantly inhibited MCT-induced increases in the expression of serotonin transporter (SERT) and phosphorylated extracellular signal-regulated kinase 1/2 and downregulated the expression of OPN, macrophage inflammatory protein-1ß and matrix metalloproteinase 2/tissue inhibitor of metalloproteinase 2. Although 2 mg/kg fluoxetine tended to ameliorate some MCT-induced changes in the lung, the differences did not always reach statistical significance. Linear regression analysis showed that there was a positive correlation between plasma OPN concentrations and mean pulmonary arterial pressure, as well as percentage medial wall thickness and percentage wall area in the pulmonary artery. 4. In conclusion, the amelioration by fluoxetine of MCT-induced pulmonary inflammation and vascular remodelling is associated with downregulation of OPN expression in rats.