Administration of Gas6 attenuates lung fibrosis via inhibition of the epithelial-mesenchymal transition and fibroblast activation.

The epithelial-mesenchymal transition (EMT) and fibroblast activation are major events in idiopathic pulmonary fibrosis pathogenesis. Here, we investigated whether growth arrest-specific protein 6 (Gas6) plays a protective role in lung fibrosis via suppression of the EMT and fibroblast activation. rGas6 administration inhibited the EMT in isolated mouse ATII cells 14 days post-BLM treatment based on morphologic cellular alterations, changes in mRNA and protein expression profiles of EMT markers, and induction of EMT-activating transcription factors. BLM-induced increases in gene expression of fibroblast activation-related markers and the invasive capacity of primary lung fibroblasts in primary lung fibroblasts were reversed by rGas6 administration. Furthermore, the hydroxyproline content and collagen accumulation in interstitial areas with damaged alveolar structures in lung tissue were reduced by rGas6 administration. Targeting Gas6/Axl signaling events with specific inhibitors of Axl (BGB324), COX-2 (NS-398), EP1/EP2 receptor (AH-6809), or PGD2 DP2 receptor (BAY-u3405) reversed the inhibitory effects of rGas6 on EMT and fibroblast activation. Finally, we confirmed the antifibrotic effects of Gas6 using Gas6-/- mice. Therefore, Gas6/Axl signaling events play a potential role in inhibition of EMT process and fibroblast activation via COX-2-derived PGE2 and PGD2 production, ultimately preventing the development of pulmonary fibrosis.

Usefulness of 3-Dimensional Computed Tomography Assessment of Femoral Tunnel after Anterior Cruciate Ligament Reconstruction.

Positioning of the femoral tunnel during anterior cruciate ligament (ACL) reconstruction is the most crucial factor for successful procedure. Owing to the inter-individual variability in the intra-articular anatomy, it can be challenging to obtain precise tunnel placement and ensure consistent results. Currently, the three-dimensional (3D) reconstruction of computed tomography (CT) scans is considered the best method for determining whether femoral tunnels are positioned correctly. Postoperative 3D-CT feedback can improve the accuracy of femoral tunnel placement. Precise tunnel formation obtained through feedback has a positive effect on graft maturation, graft failure, and clinical outcomes after surgery. However, even if femoral tunnel placement on 3D CT is appropriate, we should recognize that acute graft bending negatively affects surgical results. This review aimed to discuss the implementation of 3D-CT evaluation for predicting postoperative outcomes following ACL re-construction. Reviewing research that has performed 3D CT evaluations after ACL reconstruction can provide clinically significant evidence of the formation of ideal tunnels following anatomic ACL reconstruction.

Femoral Tunnel Geometry and Graft Inclination Angles in Anterior Cruciate Ligament Reconstruction Using a Flexible Reamer System.

Background and Objectives: The aim of this study is to investigate the femoral tunnel geometry (femoral tunsnel location, femoral graft bending angle, and femoral tunnel length) on three-dimensional (3D) computed tomography (CT) and graft inclination on magnetic resonance imaging (MRI) after anatomic anterior cruciate ligament (ACL) reconstruction using a flexible reamer system. Materials and Methods: A total of 60 patients who underwent anatomical ACL reconstruction (ACLR) using a flexible reamer system were retrospectively reviewed. One day after the ACLR procedure was performed, all patients underwent three-dimensional computed tomography (3D-CT) and magnetic resonance imaging (MRI). The femoral tunnel location, femoral graft bending angle, femoral tunnel length, and graft inclination were assessed. Results: In the 3D-CTs, the femoral tunnel was located at 29.7 ± 4.4% in the posterior to anterior (deep to shallow) direction and at 24.1 ± 5.9% in the proximal to distal (high to low) direction. The mean femoral graft bending angle was 113.9 ± 5.7°, and the mean femoral tunnel length was 35.2 ± 3.1 mm. Posterior wall breakage was observed in five patients (8.3%). In the MRIs, the mean coronal graft inclination was 69.2 ± 4.7°, and the mean sagittal graft inclination was 52.4 ± 4.6°. The results of this study demonstrated that a comparable femoral graft bending angle and longer femoral tunnel length were observed compared with the reported outcomes from previous studies that used the rigid reamer system. Conclusions: ACLR using a flexible reamer system allowed for an anatomic femoral tunnel location and a comparable graft inclination to that of the native ACL. In addition, it achieved a tolerable femoral graft bending angle and femoral tunnel length.

Shrimp miR-965 transfers tumoricidal mitochondria.

BACKGROUND: Micro RNA of Marsupenaeus japonicas has been known to promote apoptosis of tumor cells. However, the detailed mechanisms are not well understood. RESULTS: Using tomographic microscope, which can detect the internal structure of cells, we observed breast tumor cells following treatment of the miRNA. Intriguingly, we found that mitochondria migrate to an adjacent tumor cells through a tunneling nanotube. To recapitulate this process, we engineered a microfluidic device through which mitochondria were transferred. We show that this mitochondrial transfer process released endonuclease G (Endo G) into tumor cells, which we referred to herein as unsealed mitochondria. Importantly, Endo G depleted mitochondria alone did not have tumoricidal effects. Moreover, unsealed mitochondria had synergistic apoptotic effects with subtoxic dose of doxorubicin thereby mitigating cardiotoxicity. CONCLUSIONS: Together, we show that the mitochondrial transfer through microfluidics can provide potential novel strategies towards tumor cell death.

Anti-Inflammatory and Neuroprotective Mechanisms of GTS-21, an α7 Nicotinic Acetylcholine Receptor Agonist, in Neuroinflammation and Parkinson's Disease Mouse Models.

Neuroinflammation is crucial in the progression of neurodegenerative diseases. Thus, controlling neuroinflammation has been proposed as an important therapeutic strategy for neurodegenerative disease. In the present study, we examined the anti-inflammatory and neuroprotective effects of GTS-21, a selective α7 nicotinic acetylcholine receptor (α7 nAChR) agonist, in neuroinflammation and Parkinson's disease (PD) mouse models. GTS-21 inhibited the expression of inducible nitric oxide synthase (iNOS) and proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated BV2 microglial cells and primary microglia. Further research revealed that GTS-21 has anti-inflammatory properties by inhibiting PI3K/Akt, NF-κB, and upregulating AMPK, Nrf2, CREB, and PPARγ signals. The effects of GTS-21 on these pro-/anti-inflammatory signaling molecules were reversed by treatment with an α7 nAChR antagonist, suggesting that the anti-inflammatory effects of GTS-21 are mediated through α7 nAChR activation. The anti-inflammatory and neuroprotective properties of GTS-21 were then confirmed in LPS-induced systemic inflammation and MPTP-induced PD model mice. In LPS-injected mouse brains, GTS-21 reduced microglial activation and production of proinflammatory markers. Furthermore, in the brains of MPTP-injected mice, GTS-21 restored locomotor activity and dopaminergic neuronal cell death while inhibiting microglial activation and pro-inflammatory gene expression. These findings suggest that GTS-21 has therapeutic potential in neuroinflammatory and neurodegenerative diseases such as PD.

Comparable surgical outcomes of abdominal aortic aneurysm repair in patients with and without Marfan syndrome.

OBJECTIVE: Marfan syndrome (MFS) affects the cardiovascular system. Aortic root aneurysm is a pathognomonic feature of MFS; however, the abdominal aorta is rarely affected. A consensus on surveillance for the abdominal aorta in patients with MFS has not been established. In the present study, we compared the outcomes after open surgical repair (OSR) of abdominal aortic aneurysms (AAAs) in patients with and without MFS. METHODS: We conducted a retrospective, single-center cohort study from 2003 to 2020. We reviewed and compared 28 patients with MFS and 426 patients without MFS who had undergone OSR for AAAs. The baseline characteristics, medical comorbidities, previous cardiovascular surgery, anatomic features of the AAAs, and surgical treatment outcomes were compared between the two groups. RESULTS: The patients with MFS were younger than those without MFS at the AAA diagnosis (47.2 ± 12.3 vs 70.6 ± 7.9 years; P < .001). The proportion of women was also greater for those with MFS (46.4% vs 15.7%; P < .001). The AAAs were most often located at the infrarenal aorta in both groups. However, thoracoabdominal AAAs were more often found among patients with MFS (10.7% vs 0.9%; P < .012). The proportion of symptomatic patients was lower in the MFS group (3.6% vs 21.6%; P = .022). The maximum median diameter of the AAA at surgery was smaller in the patients with MFS (52 mm vs 58 mm; P = .001). However, concomitant aortic dissection (32.1% vs 3.3%; P < .001) was more prevalent among the patients with MFS. Consequent aneurysmal changes in the iliac artery after AAA repair were more frequent in the patients with MFS (7.1% vs 0%; P = .004). No significant differences were found in 30-day or overall mortality between the patients with and without MFS during a median follow-up period of 71 months (interquartile range, 24.7-121.1 months) and 26.7 months (interquartile range, 7.4-69.5 months), respectively. CONCLUSIONS: The surgical outcomes of OSR for AAAs for patients with MFS were not significantly different from those for patients without MFS in a well-established surveillance program of MFS.

Culture-Negative Mycotic Aortic Aneurysms Probably Have a Less Severe Clinical Nature Than Culture-Positive Counterparts.

BACKGROUND: Mycotic aortic aneurysm constitutes a potentially devastating disease that necessitates prompt suspicion and diagnosis. There is no exact consensus for treatment, but removal of infected tissues and prolonged use of antimicrobials based on the identified causative microorganisms seem widely acceptable and have been similarly practiced worldwide. However, some patients still show no identified microorganisms. In this study, we sought to determine whether there are any clinical significance or differences of note in culture-negative mycotic aortic aneurysms. METHODS: Between October 2003 and August 2018, 71 patients were identified as treated for mycotic aortic aneurysms at a single tertiary institution. Review of medical records and imaging studies were completed to collect the following information: demographics, previous medical/surgical history regarding potential infection sources, laboratory and radiologic findings, clinical presentations, treatment method, and morbidity and mortality rates. For analysis, patients were categorized into two groups: the blood and/or tissue culture-positive (CP) group and the blood and/or tissue culture-negative (CN) group. The latter was further divided as CN with identified microorganism by molecular biologic methods [CN(+)] and CN with no identified microorganism [CN(-)]. RESULTS: More patients in the CP group were symptomatic than were in the CN(+) group (100% vs. 80%; P = 0.034). However, identification of causative microorganisms did not result in a difference in symptom status upon comparing the [CP + CN(+)] and [CN(-)] groups. Inflammatory markers were the most elevated in the CP group and least elevated in the CN(-) group. The aneurysm growth rate seemed slower in the CN(-) group than in the CN(+) and CP groups (1.3 vs. 3.4 vs. 9 mm/month respectively). Aneurysm rupture at initial presentation was more prevalent in the CP group (33.3%). 18F-Fluorodeoxyglucose-positron emission tomography showed increased uptake regardless of whether or not the microorganisms were identified. Early mortality and disease-specific mortality rates during the follow-up period were higher in the CP group but without statistical significance. CONCLUSIONS: Compared with the CP group, the CN groups appeared clinically less severe, and also exhibited a relatively less devastating course as exhibited by the slower aneurysm expansion rate and smaller number of ruptured aneurysms at the initial presentation.

Outcomes after Elective Open Abdominal Aortic Aneurysm Repair in Octogenarians Compared to Younger Patients in Korea.

BACKGROUND: Although the first choice of treatment for abdominal aortic aneurysm (AAA) is endovascular aneurysm repair, especially in elderly patients, some patients require open surgical repair. The purpose of this study was to compare the mortality outcomes of open AAA repair between octogenarians and younger counterparts and to identify the risk factors associated with mortality. METHODS: All consecutive patients who underwent elective open AAA repair due to degenerative etiology at a single tertiary medical center between 1996 and June 2020 were included in this retrospective review. Medical records and imaging studies were reviewed to collect the following information: demographics, comorbid medical conditions, clinical presentations, radiologic findings, surgical details, and morbidity and mortality rates. For analysis, patients were divided into two groups: older and younger than 80 years of age. Multivariate analysis was performed to identify factors associated with mortality after elective open AAA repair. RESULTS: Among a total of 650 patients who underwent elective open AAA repair due to degenerative AAA during the study period, 58 (8.9%) were octogenarians and 595 (91.1%) were non-octogenarians. Patients in the octogenarian group were predominantly female and more likely to have lower body weight and body mass index (BMI), hypertension, chronic kidney disease, and lower preoperative serum hemoglobin and albumin compared with patients in the non-octogenarian group. Maximal aneurysm diameter was larger in octogenarians. During the median follow-up duration of 34.4 months for 650 patients, the median length of total hospital and intensive care unit stay was longer in octogenarians. The 30-day (1.7% vs. 0.7%, P = 0.374) and 1-year (6.9% vs. 2.9%, P = 0.108) mortality rates were not statistically significantly different between the two groups. Multivariate analysis showed that low BMI was associated with increased 30-day (odds ratio [OR], 16.339; 95% confidence interval [CI], 1.192-224.052; P = 0.037) and 1-year (OR, 8.236; CI, 2.301-29.477; P = 0.001) mortality in all patients. CONCLUSION: Because the mortality rate of octogenarians after elective open AAA repair was not significantly different compared with their younger counterparts, being elderly is not a contraindication for open AAA repair. Low BMI might be associated with increased postoperative mortality.

Lactiplantibacillusplantarum ATG-K2 Exerts an Anti-Obesity Effect in High-Fat Diet-Induced Obese Mice by Modulating the Gut Microbiome.

Obesity is a major health problem. Compelling evidence supports the beneficial effects of probiotics on obesity. However, the anti-obesity effect of probiotics remains unknown. In this study, we investigated the anti-obesity effects and potential mechanisms of Lactiplantibacillus plantarum ATG-K2 using 3T3-L1 adipocytes and high-fat diet (HFD)-induced obese mice. 3T3-L1 cells were incubated to determine the effect of lipid accumulation with lysate of L. plantarum ATG-K2. Mice were fed a normal fat diet or HFD with L. plantarum ATG-K2 and Orlistat for 8 weeks. L. plantarum ATG-K2 inhibited lipid accumulation in 3T3-L1 adipocytes, and reduced body weight gain, WAT weight, and adipocyte size in HFD-induced obese mice, concurrently with the downregulation of PPARγ, SREBP1c, and FAS and upregulation of PPARα, CTP1, UCP1, Prdm16, and ND5. Moreover, L. plantarum ATG-K2 decreased TG, T-CHO, leptin, and TNF-α levels in the serum, with corresponding gene expression levels in the intestine. L. plantarum ATG-K2 modulated the gut microbiome by increasing the abundance of the Lactobacillaceae family, which increased SCFA levels and branched SCFAs in the feces. L. plantarum ATG-K2 exhibited an anti-obesity effect and anti-hyperlipidemic effect in 3T3-L1 adipocytes and HFD-induced obese mice by alleviating the inflammatory response and regulating lipid metabolism, which may be influenced by modulation of the gut microbiome and its metabolites. Therefore, L. plantarum ATG-K2 can be a preventive and therapeutic agent for obesity.

Aging effects on the diurnal patterns of gut microbial composition in male and female mice.

Composition of the gut microbiota changes with aging and plays an important role in age-associated disease such as metabolic syndrome, cancer, and neurodegeneration. The gut microbiota composition oscillates through the day, and the disruption of their diurnal rhythm results in gut dysbiosis leading to metabolic and immune dysfunctions. It is well documented that circadian rhythm changes with age in several biological functions such as sleep, body temperature, and hormone secretion. However, it is not defined whether the diurnal pattern of gut microbial composition is affected by aging. To evaluate aging effects on the diurnal pattern of the gut microbiome, we evaluated the taxa profiles of cecal contents obtained from young and aged mice of both sexes at daytime and nighttime points by 16S rRNA gene sequencing. At the phylum level, the ratio of Firmicutes to Bacteroidetes and the relative abundances of Verrucomicrobia and Cyanobacteria were increased in aged male mice at night compared with that of young male mice. Meanwhile, the relative abundances of Sutterellaceae, Alloprevotella, Lachnospiraceae UCG-001, and Parasutterella increased in aged female mice at night compared with that of young female mice. The Lachnospiraceae NK4A136 group relative abundance increased in aged mice of both sexes but at opposite time points. These results showed the changes in diurnal patterns of gut microbial composition with aging, which varied depending on the sex of the host. We suggest that disturbed diurnal patterns of the gut microbiome can be a factor for the underlying mechanism of age-associated gut dysbiosis.

The Effect of Left Renal Vein Division on Renal Function Following Open Abdominal Aortic Surgery Using Propensity Score Matching Analysis.

BACKGROUND: Open surgery of abdominal aortic aneurysm (AAA) or aortoiliac occlusive disease (AIOD) sometimes requires left renal vein division (LRVD) to gain adequate exposure of the abdominal aorta. The aim of this study is to evaluate the effect of LRVD on the postoperative renal function using propensity score matching (PSM). METHODS: From July 1996 to January 2018, we retrospectively reviewed 698 patients who underwent open aortic surgery, including 543 AAAs and 155 AIODs, at a single institution. 66 patients (9.6%, 47 AAAs, 19 AIODs) needed LRVD during the operation. A 1:3 ratio PSM was used to control the selective bias between the LRVD and non-LRVD groups. We investigated preoperative and postoperative renal function including serum creatinine (sCr) level and estimated glomerular filtration rate (eGFR, mL/min/1.73 m2). Major complications, long-term renal function, and 30-day mortality were also compared. RESULTS: The LRVD group had a significantly higher rate of renal artery reconstruction (15.2% vs. 3.3%, P < 0.001) and suprarenal clamping (54.6% vs. 9.5%, P < 0.001) and higher incidence of juxtarenal AIOD (24.2% vs. 5.4%, P < 0.001). With PSM, 63 patients in the LRVD group and 144 patients in the non-LRVD group were enrolled in this study. The baseline characteristics were well balanced in the groups after PSM. There were no significant differences in preoperative eGFR (72.4 ± 21.3 vs. 76.1 ± 25.0, P = 0.306) and postoperative eGFR on day 3 (69.5 ± 26.6 vs. 77.5 ± 28.5, P = 0.065), day 7 (73.3 ± 24.8 vs. 78.5 ± 27.4, P = 0.264), and in the long-term follow-up period (69.0 ± 22.2 vs. 68.9 ± 27.1, P = 0.986, 50.2 month ± 45.50) in the 2 groups. Only the sCr level (1.40 ± 0.59 vs. 1.21 ± 0.62, P = 0.045) and eGFR (59.5 ± 23.9 vs. 71.4 ± 26.0, P = 0.002) were significantly worse on postoperative day 1 in the LRVD than in the non-LRVD group. There were no significant differences in 30-day mortality (1.6% vs. 1.6%, P = 1.00). CONCLUSIONS: The patients in the LVRD group underwent initial drop in renal function; however, eGFR improved during the follow-up period. There was no difference in renal function and postoperative mortality between LRVD and non-LRVD groups. Therefore, LRVD is a safe and durable procedure during complex abdominal aortic surgery.

The phosphodiesterase 10 inhibitor papaverine exerts anti-inflammatory and neuroprotective effects via the PKA signaling pathway in neuroinflammation and Parkinson's disease mouse models.

BACKGROUND: Neuroinflammation plays a pivotal role in the pathogenesis of Parkinson's disease (PD). Thus, the development of agents that can control neuroinflammation has been suggested as a promising therapeutic strategy for PD. In the present study, we investigated whether the phosphodiesterase (PDE) 10 inhibitor has anti-inflammatory and neuroprotective effects in neuroinflammation and PD mouse models. METHODS: Papaverine (PAP) was utilized as a selective inhibitor of PDE10. The effects of PAP on the expression of pro-inflammatory molecules were examined in lipopolysaccharide (LPS)-stimulated BV2 microglial cells by ELISA, RT-PCR, and Western blot analysis. The effects of PAP on transcription factors were analyzed by the electrophoretic mobility shift assay, the reporter gene assay, and Western blot analysis. Microglial activation and the expression of proinflammatory molecules were measured in the LPS- or MPTP-injected mouse brains by immunohistochemistry and RT-PCR analysis. The effect of PAP on dopaminergic neuronal cell death and neurotrophic factors were determined by immunohistochemistry and Western blot analysis. To assess mouse locomotor activity, rotarod and pole tests were performed in MPTP-injected mice. RESULTS: PAP inhibited the production of nitric oxide and proinflammatory cytokines in LPS-stimulated microglia by modulating various inflammatory signals. In addition, PAP elevated intracellular cAMP levels and CREB phosphorylation. Treatment with H89, a PKA inhibitor, reversed the anti-inflammatory effects of PAP, suggesting the critical role of PKA signaling in the anti-inflammatory effects of PAP. We verified the anti-inflammatory effects of PAP in the brains of mice with LPS-induced systemic inflammation. PAP suppressed microglial activation and proinflammatory gene expression in the brains of these mice, and these effects were reversed by H89 treatment. We further examined the effects of PAP on MPTP-injected PD model mice. MPTP-induced dopaminergic neuronal cell death and impaired locomotor activity were recovered by PAP. In addition, PAP suppressed microglial activation and proinflammatory mediators in the brains of MPTP-injected mice. CONCLUSIONS: PAP has strong anti-inflammatory and neuroprotective effects and thus may be a potential candidate for treating neuroinflammatory disorders such as PD.

MCP-1 and MIP-3α Secreted from Necrotic Cell-Treated Glioblastoma Cells Promote Migration/Infiltration of Microglia.

BACKGROUND/AIMS: Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults. The defining characteristics of GBM are diffuse infiltration of tumor cells into normal brain parenchyma, rapid growth, a high degree of infiltration of microglia and macrophages, and the presence of necrosis. Microglia/macrophages are frequently found in gliomas and they extensively infiltrate GBM tissue, up to 30% of total tumor mass. However, little is known about the effect of necrotic cells (NCs) on microglia infiltration in GBM and the tumor-infiltrating microglia-induced factors in GBMs. METHODS: In this study, to address whether necrosis or necrosis-exposed GBM cells affect the degree of microglia/macrophage infiltration, migration and invasion/infiltration assays were performed. Culture supernatants and nuclear extracts of CRT-MG cells treated or untreated with necrotic cells were analyzed using a chemokine array and electrophoretic mobility shift assay, respectively. RESULTS: The presence of NCs promoted the migration/infiltration of microglia, and GBM cell line CRT-MG cells exposed to NCs further enhanced the migration and infiltration of HMO6 microglial cells. Treatment with NCs induced mRNA and protein expression of chemokines such as Monocyte Chemoattractant Protein-1 (CCL2/MCP-1) and Macrophage Inflammatory Protein-3α (CCL20/MIP-3α) in CRT-MG cells. In particular, CCL2/MCP-1 and CCL20/MIP-3α were significantly increased in NC-treated CRT-MG cells. NCs induced DNA binding of the transcription factors Nuclear Factor (NF)-κB and Activator Protein 1 (AP-1) to the CCL2/MCP-1 and CCL20/MIP-3α promoters, leading to increased CCL2/MCP-1 and CCL20/MIP-3α mRNA and protein expression in CRT-MG cells. CONCLUSION: These results provide evidence that NCs induce the expression of CCL2/MCP-1 and CCL20/MIP-3α in glioblastoma cells through activation of NF-κB and AP-1 and facilitate the infiltration of microglia into tumor tissues.

A STAT6 Inhibitor AS1517499 Reduces Preventive Effects of Apoptotic Cell Instillation on Bleomycin-Induced Lung Fibrosis by Suppressing PPARγ.

BACKGROUND/AIMS: The signal transducer and activator of transcription 6 (STAT6) transcription factor mediates PPARγ-regulated gene expression in macrophages. However, it remains largely unknown how proximal membrane signaling events initiated by apoptotic cell recognition upregulate PPARγ expression and activate the lung homeostatic program. METHODS: The STAT6 inhibitor AS1517499 was used to determine the role of STAT6 in mediating PPARγ activity, anti-inflammatory effects, and anti-fibrotic effects induced by apoptotic cell instillation after bleomycin treatment into C57BL/6 mice. Bronchoalveolar lavage fluid, alveolar macrophages and lungs were harvested at days 2, 7, and 14 and then analyzed by real-time PCR, immunoblotting, ELISA, immunocytochemistry and immunohistochemistry assays. RESULTS: Our data demonstrate that apoptotic cell instillation after bleomycin results in prolonged enhancement of STAT6 phosphorylation in alveolar macrophages and lung. Co-administration of the STAT6 inhibitor, AS1517499, reversed the enhanced PPARγ expression and activity induced by apoptotic cell instillation after bleomycin treatment. By reducing the expression of PPARγ target genes, including CD36, macrophage mannose receptor, and arginase 1, AS1517499 inhibited efferocytosis and restored pro-inflammatory cytokine expression, neutrophil recruitment, protein levels, hydroxyproline content, and expression of fibrosis markers, including type 1 collagen α2, fibronectin, and α-smooth muscle actin. STAT6 inhibition reversed the expression profile of hepatocyte growth factor and interleukin-10. CONCLUSION: These results indicate that prolonged STAT6 activation following one-time apoptotic cell instillation facilitates continuous PPARγ activation, resulting in the resolution of bleomycin-induced lung inflammation and fibrosis.

Anti-inflammatory and anti-oxidant mechanisms of an MMP-8 inhibitor in lipoteichoic acid-stimulated rat primary astrocytes: involvement of NF-κB, Nrf2, and PPAR-γ signaling pathways.

BACKGROUND: Recent evidence suggests that reactive astrocytes play an important role in neuroinflammation and neurodegenerative diseases. Thus, controlling astrocyte reactivity has been suggested as a promising strategy for treating neurodegenerative diseases. In the present study, we investigated whether a matrix metalloproteinase (MMP)-8 inhibitor, M8I, could control neuroinflammation in lipoteichoic acid (LTA)-stimulated rat primary astrocytes. METHODS: The effects of M8I on the expression of inducible nitric oxide synthase, cytokines, and MMPs were examined in LTA-stimulated rat primary astrocytes by ELISA, RT-PCR, and Western blot analysis. The effects of M8I on reactive oxygen species (ROS) generation and phase II antioxidant enzyme expression were examined by the DCF-DA assay, RT-PCR, and Western blot analysis. The detailed molecular mechanisms underlying the anti-inflammatory and antioxidant effects of M8I were analyzed by the electrophoretic mobility shift assay, the reporter gene assay, Western blot, and RT-PCR analysis. RESULTS: Treatment with LTA, a major cell wall component of Gram-positive bacteria, led to astrocyte activation and induced the expression of inflammatory molecules such as iNOS, COX-2, and pro-inflammatory cytokines. In addition, LTA induced the expression of MMPs such as MMP-1, MMP-3, MMP-8, MMP-9, and MMP-13 in rat primary astrocytes. Based on previous reports showing that MMP-8 plays a role as a proinflammatory mediator in microglia, we investigated whether MMP-8 is also involved in inflammatory reactions of reactive astrocytes. We found that treatment of astrocytes with M8I significantly inhibited LTA-induced expression of iNOS, TNF-α, IL-1ß, IL-6, and TLR-2. In addition, M8I inhibited LTA-induced NF-κB, MAP kinase, and Akt activities, while it increased the anti-inflammatory PPAR-γ activities. Moreover, M8I showed antioxidant effects by suppressing ROS production in LTA- or H2O2-stimulated astrocytes. Interestingly, M8I increased the expression of phase II antioxidant enzymes such as hemeoxygenase-1, NQO1, catalase, and MnSOD by modulating the Nrf2/ARE signaling pathway. CONCLUSIONS: The data collectively suggest the therapeutic potential of an MMP-8 inhibitor in neuroinflammatory disorders that are associated with astrocyte reactivity.

Association between Genetic Variations of MERTK and Chronic Obstructive Pulmonary Disease in Koreans.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a debilitating lung disease. To date, a large number of clinical studies have been conducted to investigate the association between genetic variations and COPD. However, little is known regarding the genetic susceptibility of Koreans to this disease. MER receptor tyrosine kinase (MERTK) plays important roles in the inhibition of inflammation and in the clearance of apoptotic cells. Here, we investigated the association between genetic variations in MERTK and the development of COPD in Koreans. METHODS: We conducted genetic analysis of MERTK using genomic DNA samples from 87 patients with COPD and 88 healthy controls and compared the frequency of each variation or haplotype between the patient and control groups. Subsequently, the effect of each variation was evaluated using in vitro assays. RESULTS: Ten variations were identified in this study, four of them for the first time. In addition, we found that the frequency of each variation or haplotype was comparable between the patient and control groups. However, we observed that the frequency for the wild-type haplotype was higher in the control group, compared to that in the group of patients with COPD, in the subgroup analysis of current smokers, although the difference was not statistically significant (P = 0.080). In in vitro assays, we observed that none of the variations affected the activity of the promoter or the expression of MERTK. CONCLUSION: Our findings indicate that the susceptibility to COPD is not related to the genetic variations or haplotypes of MERTK in Koreans.

Exogenous Hydrogen Peroxide Induces Lipid Raft-Mediated STAT-6 Activation in T Cells.

BACKGROUND/AIMS: CD4+ T cells are a critical component of the adaptive immune response. While the mechanisms controlling the differentiation of the Th1, Th17, and regulatory T cell subsets from naïve CD4+ T cells are well described, the factors that induce Th2 differentiation are still largely unknown. METHODS: The effects of treatment with exogenous H2O2 on STAT-6 phosphorylation and activation in T cells were examined by immunoblotting, immunofluorescence and gel shift assay. Anti-CD3 antibody and methyl-ß-cyclodextrin were utilized to induce lipid raft assembly and to investigate the involvement of lipid rafts, respectively. RESULTS: Jurkat and EL-4 T cells that were exposed to H2O2 showed rapid and strong STAT-6 phosphorylation, and the extent of STAT-6 phosphorylation was enhanced by co-treatment with anti-CD3 antibody. The effect of H2O2 on STAT-6 phosphorylation and translocation was inhibited by disruption of lipid rafts. STAT-6 activation in response to H2O2 treatment regulated IL-4 gene expression, and this response was strengthened by treatment with anti-CD3. CONCLUSION: Our results indicate that reactive oxygen species such as H2O2 can act on upstream and initiating factors for activation of STAT-6 in T cells and contribute to formation of a positive feedback loop between STAT-6 and IL-4 in the Th2 differentiation process.

Treatment strategy based on the natural course of the disease for patients with spontaneous isolated abdominal aortic dissection.

OBJECTIVE: This study aimed to determine the natural history of spontaneous isolated abdominal aortic dissection (SIAAD) and to establish an optimal management strategy for patients with SIAAD. METHODS: We searched the database of thoracoabdominal computed tomography (CT) performed at a single institution from January 2003 to July 2016 using the keywords "aortic dissection" and "dissection AND aorta." Once a diagnosis of SIAAD was made, we investigated the initial clinical and morphologic features and aorta-related events for all patients and morphologic changes of the aortic dissection (AD) during the follow-up period for the patients who underwent follow-up CT scans. We compared characteristics of the patients, frequencies of clinical events (aortic rupture, intervention, death), and morphologic changes (false lumen enlargement, progression of AD, remodeling of AD, and involvement of iliac or visceral artery) during the follow-up period according to the location of AD (infrarenal vs suprarenal), symptom status (symptomatic vs asymptomatic), and gender. RESULTS: There were 210 (10.7%) patients (median age, 69.4 years [interquartile range, 61.3-74.7]; male, 73.3%) who were diagnosed with SIAAD among 1958 patients with AD. SIAAD was most frequently located at the infrarenal aorta (86.2%), extended to the iliac (12.4%) or visceral artery (2.9%), and was symptomatic in 13.3% of patients. During the study period, aortic rupture developed in two patients (0.9%), aortic intervention was required in five (2.4%), and aorta-related deaths were identified in three (1.4%). Among 138 (65.7%) patients who underwent follow-up CT scans, 81.9% showed no morphologic change or remodeling during the follow-up period (median, 25 months; range, 1-158 months; interquartile range, 12.3-49.1 months). In the meantime, false lumen enlargement and longitudinal progression of AD developed in 8.7% and 6.5% of patients, respectively. However, newly developed visceral artery extension was not found in any of the patents. When characteristics of the patients and frequencies of clinical events or late morphologic changes of AD were compared on the basis of the location of AD, symptom status, and gender, female gender, presence of symptoms, and suprarenal SIAAD were more frequently associated with aorta-related mortality. False lumen enlargement was more frequent in the suprarenal AD group than in the infrarenal AD group. CONCLUSIONS: Based on our observation, the majority of symptomatic and asymptomatic SIAAD patients can be managed conservatively unless they present with aortic rupture, concomitant large aortic aneurysm, or underlying connective tissue disease. However, a more proactive management strategy may be required for female, symptomatic patients or those with suprarenal SIAAD.

Anti-inflammatory mechanism of lonchocarpine in LPS- or poly(I:C)-induced neuroinflammation.

Neuroinflammation plays an important role in the progression of various neurodegenerative diseases. In this study, we investigated the anti-inflammatory effects of lonchocarpine, a natural compound isolated from Abrus precatorius, under in vitro and in vivo neuroinflammatory conditions induced by challenge with lipopolysaccharide (LPS)- or polyinosinic-polycytidylic acid (poly(I:C)). Lonchocarpine suppressed the expression of iNOS and proinflammatory cytokines in LPS or poly(I:C)-stimulated BV2 microglial cells. These anti-inflammatory effects were verified in brains of mice with systemic inflammation induced by administration of LPS or poly(I:C). Lonchocarpine reduced the number of Iba-1-positive activated microglia, and suppressed the mRNA expression of various proinflammatory markers in the cortex of LPS- or poly(I:C)-injected mice. Molecular mechanistic experiments showed that lonchocarpine inhibited NF-κB activity by reducing the phosphorylation and degradation of IκBα in LPS- or poly(I:C)-stimulated BV2 cells. Analysis of further upstream signaling pathways in LPS-stimulated microglia showed that lonchocarpine inhibited the phosphorylation of IκB kinase and TGFß-activated kinase 1 (TAK1). Moreover, lonchocarpine suppressed the interaction of myeloid differentiation factor 88 (MyD88) and intereleukin-1 receptor-associated kinase 4 (IRAK4). These data suggest that toll-like receptor 4 downstream signals such as MyD88/IRAK4-TAK1-NF-κB are at least partly involved in the anti-inflammatory mechanism of lonchocarpine in LPS-stimulated microglia. Its strong anti-inflammatory effects may make lonchocarpine an effective preventative drug for neuroinflammatory disorders that are associated with systemic inflammation.

Lactobacillus plantarum HAC01 regulates gut microbiota and adipose tissue accumulation in a diet-induced obesity murine model.

The functional features of Lactobacillus plantarum HAC01 (HAC01), isolated from fermented Korean kimchi, were studied with regard to the fat mass, immunometabolic biomarkers and dysbiosis in a diet-induced obesity (DIO) murine model. L. rhamnosus GG (LGG) served as reference strain and a PBS-treated group as control. The administration of L. plantarum HAC01 resulted in reduction of the mesenteric adipose depot, the conjunctive tissue closely associated with the gastrointestinal tract, where lipid oxidative gene expression was upregulated compared to the control group. Metagenome analysis of intestinal microbiota showed that both strains HAC01 and LGG influenced specific bacterial families such as the Lachnospiraceae and Ruminococcaceae rather than the phyla Firmicutes and Bacteroidetes as a whole. The relative abundance of the Lachnospiraceae (phylum Firmicutes) was significantly higher in both LAB-treated groups than in the control. Comparing the impact of the two Lactobacillus strains on microbial composition in the gut also suggests strain-specific effects. The study emphasises the need for deeper studies into functional specificity of a probiotic organism at the strain level. Alleviation of obesity-associated dysbiosis by modulation of the gut microbiota appears to be associated with "indicator" bacterial taxa such as the family Lachnospiraceae. This may provide further insight into mechanisms basic to the mode of probiotic action against obesity and associated dysbiosis.