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.

Lactobacillus paracasei ATG-E1 improves particulate matter 10 plus diesel exhaust particles (PM10D)-induced airway inflammation by regulating immune responses.

Particulate matter (PM) exposure can adversely affect respiratory function. Probiotics can alleviate the inflammatory responses in respiratory diseases. We examined the protective effects of Lactobacillus paracasei ATG-E1 isolated from the feces of a newborn baby against airway inflammation in a PM10 plus diesel exhaust particle (DEP) (PM10D)-induced airway inflammation model. BALB/c mice were exposed to PM10D by intranasal injection three times at 3-day intervals for 12 days, and L. paracasei ATG-E1 was administered orally for 12 days. Analysis of immune cell population and expression of various inflammatory mediators and gut barrier-related genes were determined in bronchoalveolar lavage fluid (BALF), lung, peyer's patch, and small intestine. A histological analysis of the lungs was performed. In addition, the in vitro safety and their safety in genomic analyses were examined. L. paracasei ATG-E1 was found to be safe in vitro and by genomic analysis. L. paracasei ATG-E1 suppressed neutrophil infiltration and the number of CD4+, CD4+CD69+, CD62L-CD44+high, CD21/35+B220+, and Gr-1+CD11b+ cells, as well as the expression of inflammatory mediators, including chemokine (C-X-C motif) ligand (CXCL)-1, macrophage inflammatory protein (MIP)-2, interleukin (IL)-17a, tumor necrosis factor (TNF)-α, and IL-6 in BALF and lungs in PM10D-induced airway inflammation. It protected against histopathological damage in the lungs of mice with PM10D-induced airway inflammation. L. paracasei ATG-E1 concomitantly increased the expression levels of the gut barrier function-related genes occludin, claudin-1, and IL-10 in the small intestine, with an increased number of CD4+ and CD4+CD25+ immune cells in the peyer's patch. L. paracasei ATG-E1 suppressed immune activation and airway inflammatory responses in the airways and lungs by restoring the lung damage by PM10D. It also regulated intestinal immunity and ameliorated the gut barrier function in the ileum. These results indicate the potential of L. paracasei ATG-E1 as an protective and therapeutic agent against airway inflammation and respiratory diseases.

Lethal effects of mitochondria via microfluidics.

Tumor cells can respond to therapeutic agents by morphologic alternations including formation of tunneling nanotubes. Using tomographic microscope, which can detect the internal structure of cells, we found that mitochondria within breast tumor cells migrate to an adjacent tumor cell through a tunneling nanotube. To investigate the relationship between mitochondria and tunneling nanotubes, mitochondria were passed through a microfluidic device that mimick tunneling nanotubes. Mitochondria, through the microfluidic device, released endonuclease G (Endo G) into adjacent tumor cells, which we referred to herein as unsealed mitochondria. Although unsealed mitochondria did not induce cell death by themselves, they induced apoptosis of tumor cells in response to caspase-3. Importantly, Endo G-depleted mitochondria were ineffective as lethal agents. Moreover, unsealed mitochondria had synergistic apoptotic effects with doxorubicin in further increasing tumor cell death. Thus, we show that the mitochondria of microfluidics can provide novel strategies toward tumor cell death.

Identification of a novel PARP4 gene promoter CpG locus associated with cisplatin chemoresistance.

The protein family of poly (ADP-ribose) polymerases (PARPs) is comprised of multifunctional nuclear enzymes. Several PARP inhibitors have been developed as new anticancer drugs to combat resistance to chemotherapy. Herein, we characterized PARP4 mRNA expression profiles in cisplatin-sensitive and cisplatin-resistant ovarian cancer cell lines. PARP4 mRNA expression was significantly upregulated in cisplatin-resistant ovarian cancer cell lines, and this upregulation was associated with the hypomethylation of specific cytosine-phosphate-guanine (CpG) sites (cg18582260 and cg17117459) on its promoter. Reduced PARP4 expression was restored by treating cisplatin-sensitive cell lines with a demethylation agent, implicating the epigenetic regulation of PARP4 expression by promoter methylation. Depletion of PARP4 expression in cisplatin-resistant cell lines reduced cisplatin chemoresistance and promoted cisplatin-induced DNA fragmentation. The differential mRNA expression and DNA methylation status at specific PARP4 promoter CpG sites (cg18582260 and cg17117459) according to cisplatin responses, was further validated in primary ovarian tumor tissues. The results showed significantly increased PARP4 mRNA expressions and decreased DNA methylation levels at specific PARP4 promoter CpG sites (cg18582260 and cg17117459) in cisplatin-resistant patients. Additionally, the DNA methylation status at cg18582260 CpG sites in ovarian tumor tissues showed fairly clear discrimination between cisplatin-resistant patients and cisplatin-sensitive patients, with high accuracy (area under the curve = 0.86, P = 0.003845). Our findings suggest that the DNA methylation status of PARP4 at the specific promoter site (cg18582260) may be a useful diagnostic biomarker for predicting the response to cisplatin in ovarian cancer patients. [BMB Reports 2023; 56(6): 347-352].

Disruption of the metC Gene Affects Methionine Biosynthesis in Pectobacterium carotovorum subsp. carotovorum Pcc21 and Reduces Soft-Rot Disease.

Plant pathogenic Pectobacterium species cause severe soft rot/blackleg diseases in many economically important crops worldwide. Pectobacterium utilizes plant cell wall degrading enzymes (PCWDEs) as the main virulence determinants for its pathogenicity. In this study, we screened a random mutant, M29 is a transposon insertion mutation in the metC gene encoding cystathionine ß-lyase that catalyzes cystathionine to homocysteine at the penultimate step in methionine biosynthesis. M29 became a methionine auxotroph and resulted in growth defects in methionine-limited conditions. Impaired growth was restored with exogenous methionine or homocysteine rather than cystathionine. The mutant exhibited reduced soft rot symptoms in Chinese cabbages and potato tubers, maintaining activities of PCWDEs and swimming motility. The mutant was unable to proliferate in both Chinese cabbages and potato tubers. The reduced virulence was partially restored by a complemented strain or 100 µM of methionine, whereas it was fully restored by the extremely high concentration (1 mM). Our transcriptomic analysis showed that genes involved in methionine biosynthesis or transporter were downregulated in the mutant. Our results demonstrate that MetC is important for methionine biosynthesis and transporter and influences its virulence through Pcc21 multiplication in plant hosts.

Venous Reconstruction in Extremity Soft Tissue Sarcoma Is Not Essential.

OBJECTIVE: Limb salvage is an important concern following complete oncologic resection for extremity soft tissue sarcoma (STS). Vascular reconstruction is essential for limb salvage. The purpose of this study was to evaluate the outcomes of vascular reconstruction in patients with extremity STS. METHODS: This is a retrospective, multi-center, case series of consecutive patients who underwent vascular reconstruction during extremity STS resection at 2 major centers in Korea. Demographics, reconstruction methods, type of conduit, surgical complications, graft patency, limb salvage rate, and patient survival were reviewed. RESULTS: From March 2005 to December 2020, 43 patients underwent vascular reconstructions during STS resection. Among the patients, 22 (51.2%) received arterial only, and 21 (48.8%) received simultaneous arterial and venous reconstructions. For the types of conduits, autologous saphenous veins (56.2%), artificial grafts (26.3%), and cryopreserved allografts (15.8%) were used. During a median follow-up of 23.8 months (interquartile range; 7.7-54.5), the overall primary patency of the reconstructed vessels was significantly higher in arteries than in veins (82.5% vs 56.3% at 12 months, P < .001). According to the type of conduit, the primary patency rate of autogenous vein seemed higher in venous reconstruction, however, there was no statistical significance in both arterial and venous reconstruction. There was no significant difference in primary arterial patency rate (P = .132) or incidence of surgical complications including postoperative edema or wound problem whether or not simultaneous venous reconstruction was performed with arterial reconstruction. The overall limb salvage rate and patient survival were 97.4%, 95.1%, and 89.4% and 91.9%, 81.7%, and 65.4% at 12, 24, and 36 months, respectively. CONCLUSIONS: Patency rates were poorer in venous reconstruction than in arterial reconstruction. In terms of arterial patency and postoperative complication, the role of simultaneous arterial and venous reconstruction seems not essential, however, it needs to be evaluated in future studies.

Pyocyanin and 1-Hydroxyphenazine Promote Anaerobic Killing of Pseudomonas aeruginosa via Single-Electron Transfer with Ferrous Iron.

Previously, it was reported that natural phenazines are able to support the anaerobic survival of Pseudomonas aeruginosa PA14 cells via electron shuttling, with electrodes poised as the terminal oxidants (Y. Wang, S. E. Kern, and D. K. Newman, J Bacteriol 192:365-369, 2010, https://doi.org/10.1128/JB.01188-09). The present study shows that both pyocyanin (PYO) and 1-hydroxyphenazine (1-OHPHZ) promoted the anaerobic killing of PA14 Δphz cells presumably via a single-electron transfer reaction with ferrous iron. However, phenazine-1-carboxylic acid (PCA) did not affect anaerobic survival in the presence of ferrous iron. Anaerobic cell death was alleviated by the addition of antioxidant compounds, which inhibit electron transfer via DNA damage. Neither superoxide dismutase (SOD) nor catalase was able to alleviate P. aeruginosa cell death, ruling out the possibility of reactive oxygen species (ROS)-induced killing. Further, the phenazine degradation profile and the redox state-associated color changes suggested that phenazine radical intermediates are likely generated by single-electron transfer. In this study, we showed that the phenazines 1-OHPHZ and PYO anaerobically killed the cell via single-electron transfer with ferrous iron and that the killing might have resulted from phenazine radicals. IMPORTANCE Pseudomonas aeruginosa is an opportunistic human pathogen which infects patients with burns, immunocompromised individuals, and in particular, the mucus that accumulates on the surface of the lung in cystic fibrosis (CF) patients. Phenazines as redox-active small molecules have been reported as important compounds for the control of cellular functions and virulence as well as anaerobic survival via electron shuttles. We show that both pyocyanin (PYO) and 1-hydroxyphenazine (1-OHPHZ) generate phenazine radical intermediates via presumably single-electron transfer reaction with ferrous iron, leading to the anaerobic killing of Pseudomonas cells. The recA mutant defect in the DNA repair system was more sensitive to anaerobic conditions. Our results collectively suggest that both phenazines anaerobically kill cells via DNA damage during electron transfer with iron.

Reprogramming of cancer-associated fibroblasts by apoptotic cancer cells inhibits lung metastasis via Notch1-WISP-1 signaling.

The interplay between apoptotic cancer cells and the tumor microenvironment modulates cancer progression and metastasis. Cancer-associated fibroblasts (CAFs) play a crucial role in promoting these events through paracrine communication. Here, we demonstrate that conditioned medium (CM) from lung CAFs exposed to apoptotic cancer cells suppresses TGF-ß1-induced migration and invasion of cancer cells and CAFs. Direct exposure of CAFs to apoptotic 344SQ cells (ApoSQ) inhibited CAF migration and invasion and the expression of CAF activation markers. Enhanced secretion of Wnt-induced signaling protein 1 (WISP-1) by CAFs exposed to ApoSQ was required for these antimigratory and anti-invasive effects. Pharmacological inhibition of Notch1 activation or siRNA-mediated Notch1 silencing prevented WISP-1 production by CAFs and reversed the antimigratory and anti-invasive effects. Enhanced expression of the Notch ligand delta-like protein 1 on the surface of ultraviolet-irradiated apoptotic lung cancer cells triggered Notch1-WISP-1 signaling. Phosphatidylserine receptor brain-specific angiogenesis inhibitor 1 (BAI1)-Rac1 signaling, which facilitated efferocytosis by CAFs, participated in crosstalk with Notch1 signaling for optimal production of WISP-1. In addition, a single injection of ApoSQ enhanced WISP-1 production, suppressed the expression of CAF activation markers in isolated Thy1+ CAFs, and inhibited lung metastasis in syngeneic immunocompetent mice via Notch1 signaling. Treatment with CM from CAFs exposed to ApoSQ suppressed tumor growth and lung metastasis, whereas treatment with WISP-1-immunodepleted CM from CAFs exposed to ApoSQ reversed the antitumorigenic and antimetastatic effects. Therefore, treatment with CM from CAFs exposed to apoptotic lung cancer cells could be therapeutically applied to suppress CAF activation, thereby preventing cancer progression and metastasis.

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.

Treatment results of carotid endarterectomy and carotid artery stenting for patients with radiation-induced carotid stenosis.

Purpose: Exposure to ionizing radiation over the head and neck accelerates atherosclerotic changes in the carotid arteries. Owing to the characteristics of radiation-induced carotid stenosis (RICS), the results regarding the optimal revascularization method for RICS vary. This study compared treatment outcomes between carotid endarterectomy (CEA) and carotid artery stenting (CAS) in RICS. Methods: This was a single-center retrospective review of consecutive patients who underwent CEA or CAS for carotid stenosis. RICS was defined as carotid stenosis (>50%) with the prior neck irradiation for cancer treatment on either side. For the analyses, demographics, comorbid conditions, carotid lesion characteristics based on imaging studies, surgical complications, neurologic outcomes, and mortality during the follow-up period were reviewed. To compare CEA and CAS results in RICS, a 1:1 propensity score matching was applied. Results: Between November 1994 and June 2021, 43 patients with RICS and 2,407 patients with non-RICS underwent carotid revascularization with CEA or CAS. RICS had fewer atherosclerotic risk factors and more frequent severe carotid stenosis and contralateral carotid occlusions than non-RICS. CAS was more commonly performed than CEA (22.9% vs. 77.1%) for RICS due to more frequent unfavorable carotid anatomy (0 vs. 16.2%). Procedure-related complications were more common in the CEA than in the CAS. However, there was no significant difference in neurologic outcomes and restenosis rates between CEA and CAS in RICS. Conclusion: Considering its lesion characteristics and cumulative incidence, RICS requires more attention than non-RICS. Although CAS has broader indications for RICS, CEA has shown acceptable results if selectively performed.

Inhibition of STAT6 Activation by AS1517499 Inhibits Expression and Activity of PPARγ in Macrophages to Resolve Acute Inflammation in Mice.

Signal transducer and activator of transcription 6 (STAT6) promotes an anti-inflammatory process by inducing the development of M2 macrophages. We investigated whether modulating STAT6 activity in macrophages using AS1517499, the specific STAT6 inhibitor, affects the restoration of homeostasis after an inflammatory insult by regulating PPARγ expression and activity. Administration of AS1517499 suppressed the enhanced STAT6 phosphorylation and nuclear translocation observed in peritoneal macrophages after zymosan injection. In addition, AS1517499 delayed resolution of acute inflammation as evidenced by enhanced secretion of pro-inflammatory cytokines, reduced secretion of anti-inflammatory cytokines in PLF and supernatants from peritoneal macrophages, and exaggerated neutrophil numbers and total protein levels in PLF. We demonstrate temporal increases in annexin A1 (AnxA1) protein and mRNA levels in peritoneal lavage fluid (PLF), peritoneal macrophages, and spleen in a murine model of zymosan-induced acute peritonitis. In vitro priming of mouse bone marrow-derived macrophages (BMDM) and peritoneal macrophages with AnxA1 induced STAT6 activation with enhanced PPARγ expression and activity. Using AS1517499, we demonstrate that inhibition of STAT6 activation delayed recovery of PPARγ expression and activity, as well as impaired efferocytosis. Taken together, these results suggest that activation of the STAT6 signaling pathway mediates PPARγ expression and activation in macrophages to resolve acute inflammation.

Gas6 Ameliorates Inflammatory Response and Apoptosis in Bleomycin-Induced Acute Lung Injury.

Acute lung injury (ALI) is characterized by alveolar damage, lung edema, and exacerbated inflammatory response. Growth arrest-specific protein 6 (Gas6) mediates many different functions, including cell survival, proliferation, inflammatory signaling, and apoptotic cell clearance (efferocytosis). The role of Gas6 in bleomycin (BLM)-induced ALI is unknown. We investigated whether exogenous administration of mouse recombinant Gas6 (rGas6) has anti-inflammatory and anti-apoptotic effects on BLM-induced ALI. Compared to mice treated with only BLM, the administration of rGas6 reduced the secretion of proinflammatory cytokines, including tumor necrosis factor-α, interleukin-1ß, and macrophage inflammatory protein-2, and increased the secretion of hepatocyte growth factor in bronchoalveolar lavage (BAL) fluid. rGas6 administration also reduced BLM-induced inflammation and apoptosis as evidenced by reduced neutrophil recruitment into the lungs, total protein levels in BAL fluid, caspase-3 activity, and TUNEL-positive lung cells in lung tissue. Apoptotic cell clearance by alveolar macrophages was also enhanced in mice treated with both BLM and rGas6 compared with mice treated with only BLM. rGas6 also had pro-resolving and anti-apoptotic effects in mouse bone marrow-derived macrophages and alveolar epithelial cell lines stimulated with BLM in vitro. These findings indicate that rGas6 may play a protective role in BLM-induced ALI.

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.

Association between ankle brachial index and development of postoperative intensive care unit delirium in patients with peripheral arterial disease.

Patients with vascular diseases are prone to developing postoperative delirium (POD). Ankle brachial index (ABI) is a non-invasive clinical indicator of lower-extremities peripheral arterial disease (PAD) and has been identified as an indicator of cognitive impairment. We investigated the association between ABI and POD. 683 PAD patients who underwent elective leg arterial bypass surgery between October 1998 and August 2019 were collected for retrospective analysis. Demographic information, comorbidities, preoperative ABI and the Rutherford classification within one month prior to surgery were obtained. POD was assessed using the Confusion assessment method -intensive care unit. Logistic regression and receiver operating characteristics (ROC) curve analysis were used to assess the association between ABI and POD. The mean value of ABI was significantly lower in patients with POD than it was those without POD. Older age, more medical comorbidities, longer length of surgery, decreased ABI, and higher Rutherford class were all significantly associated with POD. The area under ROC (0.74) revealed that ABI below 0.35 was associated with development of POD. Lower preoperative ABI was associated with POD in PAD patients who underwent arterial bypass surgery.

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.

Cancer-associated fibroblasts activated by miR-196a promote the migration and invasion of lung cancer cells.

Fibroblasts in the tumor microenvironment, known as cancer-associated fibroblasts (CAFs), promote the migration, invasion, and metastasis of cancer cells when they are activated through diverse processes, including post-transcriptional regulation by microRNAs (miRNAs). To identify the miRNAs that regulate CAF activation, we used NanoString to profile miRNA expression within normal mouse lung fibroblasts (LFs) and CAFs. Based on NanoString profiling, miR-196a was selected as a candidate that was up-regulated in CAFs. miR-196a-overexpressed LFs (LF-196a) promoted the migration and invasion of lung cancer cells in co-culture systems (Transwell migration and spheroid invasion assays). ANXA1 was confirmed as a direct target of miR-196a, and adding back ANXA1 to LF-196a restored the cancer cell invasion promoted by miR-196a. miR-196a increased CCL2 secretion in fibroblasts, and that was suppressed by ANXA1. Furthermore, blocking CCL2 impeded cancer spheroid invasion. In lung adenocarcinoma patients, high miR-196a expression was associated with poor prognosis. Collectively, our results suggest that CAF-specific miR-196a promotes lung cancer progression in the tumor microenvironment via ANXA1 and CCL2 and that miR-196a will be a good therapeutic target or biomarker in lung adenocarcinoma.

STAT6 Signaling Mediates PPARγ Activation and Resolution of Acute Sterile Inflammation in Mice.

The signal transducer and activator of transcription 6 (STAT6) transcription factor promotes activation of the peroxisome proliferator-activated receptor gamma (PPARγ) pathway in macrophages. Little is known about the effect of proximal signal transduction leading to PPARγ activation for the resolution of acute inflammation. Here, we studied the role of STAT6 signaling in PPARγ activation and the resolution of acute sterile inflammation in a murine model of zymosan-induced peritonitis. First, we showed that STAT6 is aberrantly activated in peritoneal macrophages after zymosan injection. Utilizing STAT6-/- and wild-type (WT) mice, we found that STAT6 deficiency further enhanced zymosan-induced proinflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-6, and macrophage inflammatory protein-2 in peritoneal lavage fluid (PLF) and serum, neutrophil numbers and total protein amount in PLF, but reduced proresolving molecules, such as IL-10 and hepatocyte growth factor, in PLF. The peritoneal macrophages and spleens of STAT6-/- mice exhibited lower mRNA and protein levels of PPARγ and its target molecules over the course of inflammation than those of WT mice. The deficiency of STAT6 was shown to impair efferocytosis by peritoneal macrophages. Taken together, these results suggest that enhanced STAT6 signaling results in PPARγ-mediated macrophage programming, contributing to increased efferocytosis and inflammation resolution.

Apoptosis inhibitor of macrophage (AIM) contributes to IL-10-induced anti-inflammatory response through inhibition of inflammasome activation.

Apoptosis inhibitor of macrophage (AIM) modulates the signaling in inflammatory responses, including infection, cancer, or other immune diseases. Recent studies suggest that like interleukin-10 (IL-10), AIM is involved in alternatively activated (M2) macrophage polarization. We aimed to understand whether and how AIM is involved in IL-10-induced inhibition of inflammasome activation and resolution of inflammation. First, we demonstrated that IL-10 induced increases in mRNA and protein expression of AIM in murine bone marrow-derived macrophages (BMDM). In addition, genetic and pharmacologic inhibition of STAT3 (signal transducer and activator of transcription 3) reduced IL-10-induced AIM expression. We also found that IL-10-induced STAT3 activity enhanced the AIM promoter activity by directly binding the promoter of the AIM gene. Additionally, reduction of LPS/adenosine triphosphate (ATP)-induced IL-1ß production and caspase-1 activation by IL-10 was reversed in BMDM from AIM-/- mice. Treatment of BMDM from both wild type (WT) and IL-10-/- mice with recombinant AIM showed the inhibitory effects on IL-1ß and IL-18 production and caspase-1 activation. Endogenous and exogenous AIM inhibited apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC) speck formation. In LPS-induced acute peritonitis, inhibition of IL-1ß and IL-18 production in peritoneal lavage fluid (PLF) and serum, reduction of caspase-1 activation in peritoneal macrophages, and reduction of numbers of neutrophils and peritoneal macrophages in PLF by administration of IL-10 were not evident in AIM-/- mice. Our in vitro and in vivo data reveal a novel role of AIM in the inhibition of inflammasome-mediated caspase-1 activation and IL-1ß and IL-18 production.