Tuberculous pleural effusion-induced Arg-1+ macrophage polarization contributes to lung cancer progression via autophagy signaling.

BACKGROUND: The association between tuberculous fibrosis and lung cancer development has been reported by some epidemiological and experimental studies; however, its underlying mechanisms remain unclear, and the role of macrophage (MФ) polarization in cancer progression is unknown. The aim of the present study was to investigate the role of M2 Arg-1+ MФ in tuberculous pleurisy-assisted tumorigenicity in vitro and in vivo. METHODS: The interactions between tuberculous pleural effusion (TPE)-induced M2 Arg-1+ MФ and A549 lung cancer cells were evaluated. A murine model injected with cancer cells 2 weeks after Mycobacterium bovis bacillus Calmette-Guérin pleural infection was used to validate the involvement of tuberculous fibrosis to tumor invasion. RESULTS: Increased CXCL9 and CXCL10 levels of TPE induced M2 Arg-1+ MФ polarization of murine bone marrow-derived MФ. TPE-induced M2 Arg-1+ MФ polarization facilitated lung cancer proliferation via autophagy signaling and E-cadherin signaling in vitro. An inhibitor of arginase-1 targeting M2 Arg-1+ MФ both in vitro and in vivo significantly reduced tuberculous fibrosis-induced metastatic potential of lung cancer and decreased autophagy signaling and E-cadherin expression. CONCLUSION: Tuberculous pleural fibrosis induces M2 Arg-1+ polarization, and M2 Arg-1+ MФ contribute to lung cancer metastasis via autophagy and E-cadherin signaling. Therefore, M2 Arg-1+ tumor associated MФ may be a novel therapeutic target for tuberculous fibrosis-induced lung cancer progression.

Differences in Neuropathology between Nitroglycerin-Induced Mouse Models of Episodic and Chronic Migraine.

Multiple animal models of migraine have been used to develop new therapies. Understanding the transition from episodic (EM) to chronic migraine (CM) is crucial. We established models mimicking EM and CM pain and assessed neuropathological differences. EM and CM models were induced with single NTG or multiple injections over 9 days. Mechanical hypersensitivity was assessed. Immunofluorescence utilized c-Fos, NeuN, and Iba1. Proinflammatory and anti-inflammatory markers were analyzed. Neuropeptides (CGRP, VIP, PACAP, and substance P) were assessed. Mechanical thresholds were similar. Notable neuropathological distinctions were observed in Sp5C and ACC. ACC showed increased c-Fos and NeuN expression in CM (p < 0.001) and unchanged in EM. Sp5C had higher c-Fos and NeuN expression in EM (p < 0.001). Iba1 was upregulated in Sp5C of EM and ACC of CM (p < 0.001). Proinflammatory markers were strongly expressed in Sp5C of EM and ACC of CM. CGRP expression was elevated in both regions and was higher in CM. VIP exhibited higher levels in the Sp5C of EM and ACC of CM, whereas PACAP and substance P were expressed in the Sp5C in both models. Despite similar thresholds, distinctive neuropathological differences in Sp5C and ACC between EM and CM models suggest a role in the EM to CM transformation.

Structural basis of chromatin regulation by histone variant H2A.Z.

The importance of histone variant H2A.Z in transcription regulation has been well established, yet its mechanism-of-action remains enigmatic. Conflicting evidence exists in support of both an activating and a repressive role of H2A.Z in transcription. Here we report cryo-electron microscopy (cryo-EM) structures of nucleosomes and chromatin fibers containing H2A.Z and those containing canonical H2A. The structures show that H2A.Z incorporation results in substantial structural changes in both nucleosome and chromatin fiber. While H2A.Z increases the mobility of DNA terminus in nucleosomes, it simultaneously enables nucleosome arrays to form a more regular and condensed chromatin fiber. We also demonstrated that H2A.Z's ability to enhance nucleosomal DNA mobility is largely attributed to its characteristic shorter C-terminus. Our study provides the structural basis for H2A.Z-mediated chromatin regulation, showing that the increase flexibility of the DNA termini in H2A.Z nucleosomes is central to its dual-functions in chromatin regulation and in transcription.

Oxiracetam alleviates anti-inflammatory activity and ameliorates cognitive impairment in the early phase of traumatic brain injury.

BACKGROUND: We aimed to investigate the effects of oxiracetam on cognitive impairment in the early phase of traumatic brain injury (TBI), for which no specific treatment is currently available. METHODS: The in vitro study used a cell injury controller to damage SH-SY5Y cells and evaluate the effect of oxiracetam at a dosage of 100 nM. The in vivo study used a stereotaxic impactor to induce a TBI model in C57BL/6 J mice and analyzed immunohistochemical changes and cognitive function after an intraperitoneal injection of oxiracetam (30 mg/kg/day) for 5 days. The number of mice used in this study was 60. They were divided into three groups (sham, TBI, and TBI with oxiracetam treatment) (20 mice in each group). RESULTS: The in vitro study showed that oxiracetam treatment resulted in increased superoxide dismutase (SOD)1 and SOD2 mRNA expression. The mRNA and protein expression of COX-2, NLRP3, caspase-1, and interleukin (IL)-1 ß were decreased after oxiracetam treatment, along with decreases in intracellular reactive oxygen species production and apoptotic effects. TBI mice treated with oxiracetam exhibited the loss of fewer cortical damaged lesions, less brain edema, and fewer Fluoro-Jade B (FJB)-positive and terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL)-positive cells compared to those without oxiracetam treatment. The mRNA and protein expression of COX-2, NLRP3, caspase-1, and IL-1ß were decreased significantly after oxiracetam treatment. These inflammation-related markers, which colocalized with Iba-1-positive or GFAP-positive cells after TBI, were also decreased after oxiracetam treatment. TBI mice treated with oxiracetam had a smaller decrease in preference and more latency time than those not treated with oxiracetam, suggesting the amelioration of impaired cognitive impairment. CONCLUSIONS: Oxiracetam may be helpful in restoring cognitive impairment by ameliorating neuroinflammation in the early phase of TBI.

Auditory or Audiovisual Stimulation Ameliorates Cognitive Impairment and Neuropathology in ApoE4 Knock-In Mice.

We hypothesized that auditory stimulation could reduce the progression of Alzheimer's disease (AD), and that audiovisual stimulation could have additional effects through multisensory integration. We exposed 12 month old Apoetm1.1(APOE*4)Adiuj mice (a mouse model of sporadic AD) to auditory (A) or audiovisual stimulation (AV) at 40 Hz for 14 days in a soundproof chamber system (no stimulation, N). Behavioral tests were performed before and after each session, and their brain tissues were assessed for amyloid-beta expression and apoptotic cell death, after 14 days. Furthermore, brain levels of acetylcholine and apoptosis-related proteins were analyzed. In the Y-maze test, the percentage relative alternation was significantly higher in group A than in group N mice. Amyloid-beta and TUNEL positivity in the hippocampal CA3 region was significantly lower in group A and group AV mice than in group N mice (p < 0.05). Acetylcholine levels were significantly higher in group A and group AV mice than in group N mice (p < 0.05). Compared to group N mice, expression of the proapoptotic proteins Bax and caspase-3 was lower in group A, and expression of the antiapoptotic protein Bcl-2 was higher in group AV. In a mouse model of early-stage sporadic AD, auditory or audiovisual stimulation improved cognitive performance and neuropathology.

Human embryonic stem cell-derived cerebral organoids for treatment of mild traumatic brain injury in a mouse model.

OBJECTIVE: There are no effective treatments for relieving neuronal dysfunction after mild traumatic brain injury (TBI). Here, we evaluated therapeutic efficacy of human embryonic stem cell-derived cerebral organoids (hCOs) in a mild TBI model, in terms of repair of damaged cortical regions, neurogenesis, and improved cognitive function. METHODS: Male C57BL/6 J mice were randomly divided into sham-operated, mild TBI, and mild TBI with hCO groups. hCOs cultured at 8 weeks were used for transplantation. Mice were sacrificed at 7 and 14 days after transplantation followed by immunofluorescence staining, cytokine profile microarray, and novel object recognition test. RESULTS: 8W-hCOs transplantation significantly reduced neuronal cell death, recovered microvessel density, and promoted neurogenesis in the ipsilateral subventricular zone and dentate gyrus of hippocampus after mild TBI. In addition, increased angiogenesis into the engrafted hCOs was observed. Microarray results of hCOs revealed neuronal differentiation potential and higher expression of early brain development proteins associated with neurogenesis, angiogenesis and extracellular matrix remodeling. Ultimately, 8W-hCO transplantation resulted in reconstruction of damaged cortex and improvement in cognitive function after mild TBI. CONCLUSION: hCO transplantation may be feasible for treating mild TBI-related neuronal dysfunction via reconstruction of damaged cortex and neurogenesis in the hippocampus.

MicroRNA 148a Suppresses Tuberculous Fibrosis by Targeting NOX4 and POLDIP2.

Extracellular matrix production by pleural mesothelial cells in response to Mycobacterium tuberculosis contributes to tuberculous fibrosis. NOX4 is involved in the pathogenesis of tuberculous fibrosis. In this study, we evaluated whether NOX4 gene-targeting microRNAs showed protective effects in tuberculosis fibrosis. TargetScan prediction software was used to identify candidate microRNAs that bind the 3' UTRs of NOX4, and microRNA-148a (miR-148a) was selected as the best miRNA candidate. A repressed and forced expression assay in Met5A cells was performed to investigate the causal relationship between miR-148a and NOX4. The role of miR-148a in tuberculous pleural fibrosis was studied using a murine model of Mycobacterium bovis bacillus Calmette-Guérin (BCG) pleural infection. Heat-killed M. tuberculosis (HKMT) induces NOX4 and POLDIP2 expression. We demonstrated the inhibitory effect of miR-148a on NOX4 and POLDIP2 expression. The increased expression of miR-148a suppressed HKMT-induced collagen-1A synthesis in PMC cells. In the BCG pleurisy model, miR-148a significantly reduced fibrogenesis and epithelial mesenchymal transition. High levels of miR-148a in tuberculous pleural effusion can be interpreted as a self-limiting homeostatic response. Our data indicate that miR-148a may protect against tuberculous pleural fibrosis by regulating NOX4 and POLDIP2.

IDO and CD40 May Be Key Molecules for Immunomodulatory Capacity of the Primed Tonsil-Derived Mesenchymal Stem Cells.

Background: Tonsil-derived mesenchymal stem cells (T-MSCs) were reported to have suppressive effect on T cells, yet much remains unknown about the underlying mechanisms supporting this effect. We investigated the underlying mechanism of the immunomodulatory effect of T-MSCs on immune cell proliferation and cytokine production. Methods: We isolated T-MSCs from human palatine tonsil and evaluated the immunomodulatory capacity using RT-PCR, ELISA, and flow cytometry. Additionally, we assessed the expression of various soluble factors and several costimulatory molecules to detect the priming effect on T-MSCs. Results: T-MSCs significantly inhibited the immune cell proliferation and cytokine expression (TNF-α and IFN-γ) in the direct co-culture, but there was no suppressive effect in indirect co-culture. Additionally, we detected a remarkably higher expression of indoleamine 2,3-dioxygenase (IDO) in the primed T-MSCs having co-expression CD40. Moreover, immune cells or CD4+ T cells showed lower TNF-α, IFN-γ, and IL-4 expression when the primed T-MSC were added; whereas those findings were reversed when the inhibitor for IDO (not IL-4) or CD40 were added. Furthermore, T-bet and GATA3 levels were significantly decreased in the co-cultures of the primed T-MSCs and CD4+ T cells; whereas those findings were reversed when we added the neutralizing anti-CD40 antibody. Conclusions: Primed T-MSCs expressing IDO and CD40 may have immunomodulatory capacity via Th1-mediated and Th2-mediated immune response.

Hearing loss through apoptosis of the spiral ganglion neurons in apolipoprotein E knockout mice fed with a western diet.

Age-related hearing loss (ARHL) is a neurodegenerative disease associated with an aged population. ARHL is influenced by biological factors such as aging, sex difference, and atherosclerosis. The mechanisms of ARHL caused by atherosclerosis have not been previously determined in apolipoprotein E knockout (ApoE KO) male mice. To investigate the onset and cause of the hearing loss, ApoE KO male mice were treated with a western diet (ApoE KO-WD) for 16 weeks. The lipid profile, atherosclerotic plaques throughout the aorta, and auditory brainstem response (ABR) thresholds were measured in the ApoE KO-WD male mice. The expression of S100 calcium-binding protein B (S100B), a neuronal damage biomarker, was also observed. Reactive oxygen species (ROS) and apoptosis rates were detected in the cochlea of the ApoE KO male mice. Atherosclerotic plaques on the aorta and ABR thresholds were significantly increased in the ApoE KO-WD male mice at 24 weeks of age. ABR thresholds had a statistically significant positive correlation with the area of atherosclerotic plaques (r = 0.783, p = 0.013) in male mice at 24 weeks of age. S100B protein expression and the dihydroethidium (DHE) reaction to ROS in the cochlear spiral ganglion neurons (SGNs) were significantly increased in the ApoE KO and ApoE KO-WD male mice. Cells positive for active caspase-3 and terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) in the SGNs were significantly increased in ApoE KO-WD male mice indicating an increased rate of cellular apoptosis. In conclusion, ROS in the SGNs were activated by increased S100B expression in ApoE KO-WD male mice, and this resulted in an increased apoptosis rate. Thus, hearing loss began at 16 weeks in ApoE KO-WD male mice. Our results suggest that the ApoE KO-WD male mice are a suitable animal model for studying ARHL associated with exacerbated atherosclerosis.

Improving glycemic control in model mice with type 2 diabetes by increasing superoxide dismutase (SOD) activity using silk fibroin hydrolysate (SFH).

Islet cell dysfunction in type 2 diabetes is primarily attributed to the increased apoptosis of pancreatic beta cells. Silk fibroin hydrolysate (SFH) has an effect on blood in type 2 diabetes model mice (C57BL/KsJ-db/db). However, its exact mechanism is unknown. The type 2 diabetes model mice were randomly divided into non-diabetic mice (ND), diabetic mice (DB), and diabetic mice treated with silk fibroin hydrolysate (DB-SFH). The results showed that SFH significantly decreased fasting blood glucose and hemoglobin A1c (HbA1c). The oral glucose tolerance and insulin tolerance were significantly improved in the DB-SFH group. The DB-SFH group exhibited increased superoxide dismutase (SOD) activity in the plasma, as well as increased Mn-SOD and CuZn-SOD activities in the pancreatic islets. Furthermore, the pancreatic islet cells' death was decreased in the DB-SFH group. In the DB-SFH group, the protein expression of caspase-3 was significantly decreased compared with the DB group. The expression of the Nkx6.1 and Pdx1 proteins were increased in the DB-SFH group. The results suggest that SFH prevents the degeneration of pancreatic islets via increasing SOD while hyperglycemia is alleviated by maintaining beta cell mass in type 2 diabetes model mice.

Structural and Biochemical Characterization of the Nucleosome Containing Variants H3.3 and H2A.Z.

Variant H3.3, along with H2A.Z, is notably enriched at promoter regions and is commonly associated with transcriptional activation. However, the specific molecular mechanisms through which H3.3 influences chromatin dynamics at transcription start sites, and its role in gene regulation, remain elusive. Using a combination of biochemistry and cryo-electron microscopy (cryo-EM), we show that the inclusion of H3.3 alone does not induce discernible changes in nucleosome DNA dynamics. Conversely, the presence of both H3.3 and H2A.Z enhances DNA's flexibility similarly to H2A.Z alone. Interestingly, our findings suggest that the presence of H3.3 in the H2A.Z nucleosome provides slightly increased protection to DNA at internal sites within the nucleosome. These results imply that while H2A.Z at active promoters promotes the formation of more accessible nucleosomes with increased DNA accessibility to facilitate transcription, the simultaneous presence of H3.3 offers an additional mechanism to fine-tune nucleosome accessibility and the chromatin environment.

Modeling of the brain-lung axis using organoids in traumatic brain injury: an updated review.

Clinical outcome after traumatic brain injury (TBI) is closely associated conditions of other organs, especially lungs as well as degree of brain injury. Even if there is no direct lung damage, severe brain injury can enhance sympathetic tones on blood vessels and vascular resistance, resulting in neurogenic pulmonary edema. Conversely, lung damage can worsen brain damage by dysregulating immunity. These findings suggest the importance of brain-lung axis interactions in TBI. However, little research has been conducted on the topic. An advanced disease model using stem cell technology may be an alternative for investigating the brain and lungs simultaneously but separately, as they can be potential candidates for improving the clinical outcomes of TBI.In this review, we describe the importance of brain-lung axis interactions in TBI by focusing on the concepts and reproducibility of brain and lung organoids in vitro. We also summarize recent research using pluripotent stem cell-derived brain organoids and their preclinical applications in various brain disease conditions and explore how they mimic the brain-lung axis. Reviewing the current status and discussing the limitations and potential perspectives in organoid research may offer a better understanding of pathophysiological interactions between the brain and lung after TBI.

Bifunctional Tumor-Targeted Bioprobe for Phothotheranosis.

Background: Near-infrared (NIR) phototheranostics provide promising noninvasive imaging and treatment for head and neck squamous cell carcinoma (HNSCC), capitalizing on its adjacency to skin or mucosal surfaces. Activated by laser irradiation, targeted NIR fluorophores can selectively eradicate cancer cells, harnessing the power of synergistic photodynamic therapy and photothermal therapy. However, there is a paucity of NIR bioprobes showing tumor-specific targeting and effective phototheranosis without hurting surrounding healthy tissues. Methods: We engineered a tumor-specific bifunctional NIR bioprobe designed to precisely target HNSCC and induce phototheranosis using bioconjugation of a cyclic arginine-glycine-aspartic acid (cRGD) motif and zwitterionic polymethine NIR fluorophore. The cytotoxic effects of cRGD-ZW800-PEG were measured by assessing heat and reactive oxygen species (ROS) generation upon an 808-nm laser irradiation. We then determined the in vivo efficacy of cRGD-ZW800-PEG in the FaDu xenograft mouse model of HNSCC, as well as its biodistribution and clearance, using a customized portable NIR imaging system. Results: Real-time NIR imaging revealed that intravenously administered cRGD-ZW800-PEG targeted tumors rapidly within 4 h postintravenous injection in tumor-bearing mice. Upon laser irradiation, cRGD-ZW800-PEG produced ROS and heat simultaneously and exhibited synergistic photothermal and photodynamic effects on the tumoral tissue without affecting the neighboring healthy tissues. Importantly, all unbound bioprobes were cleared through renal excretion. Conclusions: By harnessing phototheranosis in combination with tailored tumor selectivity, our targeted bioprobe ushers in a promising paradigm in cancer treatment. It promises safer and more efficacious therapeutic avenues against cancer, marking a substantial advancement in the field.

Bone-Marrow-Derived Mesenchymal Stem Cells Attenuate Behavioral and Cognitive Dysfunction after Subarachnoid Hemorrhage via HMGB1-RAGE Axis Mediation.

We evaluated the therapeutic effects of bone-marrow-derived mesenchymal stem cells (BMSCs) on behavioral and cognitive function in a mouse model of mild subarachnoid hemorrhage (SAH) and explored the underlying mechanisms in conjunction with the HMGB1-RAGE axis. The SAH models were generated in a total of 126 male C57BL/6J mice via endovascular perforation and evaluated 24 h and 72 h after the intravenous administration of BMSCs (3 × 105 cells). The BMSCs were administered once, at 3 h, or twice, at 3 h and 48 h after the model induction. The therapeutic effects of the BMSCs were compared to those of the saline administration. Compared to saline-treated SAH-model mice, at 3 h, the mice with mild SAH treated with the BMSCs showed significant improvements in their neurological scores and cerebral edema. The administration of the BMSCs decreased the mRNA expression of HMGB1, RAGE, TLR4, and MyD88, as well as the protein expression of HMGB1 and phosphorylated NF-kB p65. Furthermore, the numbers of slips per walking time, impairments in short-term memory, and the recognition of novel objects were improved. There was some improvement in inflammatory-marker levels and cognitive function according to the BMSCs' administration times, but no large differences were seen. The administration of BMSCs improved behavioral and cognitive dysfunction by ameliorating HMGB1-RAGE axis-mediated neuroinflammation after SAH.

Therapeutic effect of a hydrogel-based neural stem cell delivery sheet for mild traumatic brain injury.

OBJECTIVE: There are no effective clinically applicable treatments for neuronal dysfunction after mild traumatic brain injury (TBI). Here, we evaluated the therapeutic effect of a new delivery method of mouse neural stem cell (mNSC) spheroids using a hydrogel, in terms of improvement in damaged cortical lesions and cognitive impairment after mild TBI. METHODS: mNSCs were isolated from the subventricular zone and subgranular zone by a hydrogel-based culture system. GFP-transduced mNSCs were generated into spheroids and wrapped into a sheet for transplantation. Male C57BL/6J mice were randomly divided into four groups: sham operation, TBI, TBI with mNSC spheroids, and TBI with mNSC spheroid sheet transplantation covering the damaged cortex. Histopathological and immunohistochemical features and cognitive function were evaluated 7, 14, and 28 days after transplantation following TBI. RESULTS: Hydrogel-based culture systems and mNSC isolation were successfully established from the adult mice. Essential transcription factors for NSCs, such as SOX2, PAX6, Olig2, nestin, and doublecortin (DCX), were highly expressed in the mNSCs. A transplanted hydrogel-based mNSC spheroid sheet showed good engraftment and survival ability, differentiated into TUJ1-positive neurons, promoted angiogenesis, and reduced neuronal degeneration. Also, TBI mice treated with mNSC spheroid sheet transplantation exhibited a significantly increased preference for a new object, suggesting improved cognitive function compared to the mNSC spheroids or no treatment groups. CONCLUSION: Transplantation with a hydrogel-based mNSC spheroid sheet showed engraftment, migration, and stability of delivered cells in a hostile microenvironment after TBI, resulting in improved cognitive function via reconstruction of the damaged cortex. STATEMENT OF SIGNIFICANCE: This study presents the therapeutic effect of a new delivery method of mouse neural stem cells spheroids using a hydrogel, in terms of improvement in damaged cortical lesions and cognitive impairment after traumatic brain injury. Collagen/fibrin hydrogel allowed long-term survival and migratory ability of NSCs spheroids. Furthermore, transplanted hydrogel-based mNSCs spheroids sheet showed good engraftment, migration, and stability of delivered cells in a hostile microenvironment, resulting in reconstruction of the damaged cortex and improved cognitive function after TBI. Therefore, we suggest that a hydrogel-based mNSCs spheroids sheet could help to improve cognitive impairment after TBI.

Autophagy and mitophagy-related extracellular mitochondrial dysfunction of cerebrospinal fluid cells in patients with hemorrhagic moyamoya disease.

We aimed to investigate whether mitochondrial dysfunction in extracellular cerebrospinal fluid (CSF), which is associated with autophagy and mitophagy, might be involved in neurological outcomes in adult patients with hemorrhagic moyamoya disease (MMD) whose pathogenesis related to poor outcomes is not well-known. CSF samples were collected from 43 adult MMD patients and analyzed according to outcomes at 3 months. Fluorescence-activated cell sorter analysis (FACS) and the JC-1 red/green ratio were used to assess mitochondrial cells and intact mitochondrial membrane potential (MMP). We performed quantitative real-time polymerase chain reaction and Western blotting analyses of autophagy and mitophagy-related markers, including HIF1α, ATG5, pBECN1, BECN1, BAX, BNIP3L, DAPK1, and PINK1. Finally, FACS analysis with specific fluorescence-conjugated antibodies was performed to evaluate the potential cellular origin of CSF mitochondrial cells. Twenty-seven females (62.8%) with a mean age of 47.4 ± 9.7 years were included in the study. Among 43 patients with hemorrhagic MMD, 23 (53.5%) had poor outcomes. The difference in MMP was evident between the two groups (2.4 ± 0.2 in patients with poor outcome vs. 3.5 ± 0.4 in patients with good outcome; p = 0.02). A significantly higher expression (2-ΔCt) of HIF1α, ATG5, DAPK1 followed by BAX and BNIP3L mRNA and protein was also observed in poor-outcome patients compared to those with good outcomes. Higher percentage of vWF-positive mitochondria, suggesting endothelial cell origins, was observed in patients with good outcome compared with those with poor outcome (25.0 ± 1.4% in patients with good outcome vs. 17.5 ± 1.5% in those with poor outcome; p < 0.01). We observed the association between increased mitochondrial dysfunction concomitant with autophagy and mitophagy in CSF cells and neurological outcomes in adult patients with hemorrhagic MMD. Further prospective multicenter studies are needed to determine whether it has a diagnostic value for risk prediction.

Fluidic integrated 3D bioprinting system to sustain cell viability towards larynx fabrication.

Herein, we report the first study to create a three-dimensional (3D) bioprinted artificial larynx for whole-laryngeal replacement. Our 3D bio-printed larynx was generated using extrusion-based 3D bioprinter with rabbit's chondrocyte-laden gelatin methacryloyl (GelMA)/glycidyl-methacrylated hyaluronic acid (GMHA) hybrid bioink. We used a polycaprolactone (PCL) outer framework incorporated with pores to achieve the structural strength of printed constructs, as well as to provide a suitable microenvironment to support printed cells. Notably, we established a novel fluidics supply (FS) system that simultaneously supplies basal medium together with a 3D bioprinting process, thereby improving cell survival during the printing process. Our results showed that the FS system enhanced post-printing cell viability, which enabled the generation of a large-scale cell-laden artificial laryngeal framework. Additionally, the incorporation of the PCL outer framework with pores and inner hydrogel provides structural stability and sufficient nutrient/oxygen transport. An animal study confirmed that the transplanted 3D bio-larynx successfully maintained the airway. With further development, our new strategy holds great potential for fabricating human-scale larynxes with in vivo-like biological functions for laryngectomy patients.

Anti-inflammatory and Anti-bacterial Effects of Allicin-coated Tracheal Tube on Trachea Mucosa.

BACKGROUND/AIM: Allicin has been known to improve wound healing via antimicrobial and anti-inflammatory properties. The aim of this study was to evaluate whether an allicin-coated tracheal tube can prevent tracheal stenosis through improving wound healing after tracheal injury. MATERIALS AND METHODS: Allicin-coated silicone tracheal tube (t-tube) was prepared by the polydopamine-mediated coating method. Tracheal mucosa was injured, and an allicin-coated t-tube was placed into the trachea to evaluate mucosal changes until designated time point. Anti-inflammatory, anti-bacterial and cytotoxic effects of allicin were also investigated in in vitro. RESULTS: Allicin- coated silicone was not cytotoxic, and it showed anti-inflammatory and anti-bacterial effects in in vitro analysis. The use of allicin-coated t-tube in a rabbit model showed favorable mucosal healing with significant decrease of proinflammatory cytokines compared to the non-coated tube group. The allicin-coated tube showed obvious decreased number of cocci-shaped bacterial attached to the tube surface. From the histological point of view, the allicin- coated tube showed faster regeneration of the normal respiratory epithelial structure compared to the non-coated group. CONCLUSION: Allicin-coated t-tube showed anti-inflammatory and anti-bacterial effects on injured tracheal mucosa. We suggest that allicin-coated t-tube can be used for promoting physiological wound healing to prevent laryngotracheal stenosis.

The Therapeutic Role of Nanoparticle Shape in Traumatic Brain Injury : An in vitro Comparative Study.

OBJECTIVE: To perform a comparative analysis of therapeutic effects associated with two different shapes of ceria nanoparticles, ceria nanorods (Ceria NRs) and ceria nanospheres (Ceria NSs), in an in vitro model of traumatic brain injury (TBI). METHODS: In vitro TBI was induced using six-well confluent plates by manually scratching with a sterile pipette tip in a 6×6-square grid. The cells were then incubated and classified into cells with scratch injury without nanoparticles and cells with scratch injury, which were treated separately with 1.16 mM of Ceria NSs and Ceria NRs. Antioxidant activities and anti-inflammatory effects were analyzed. RESULTS: Ceria NRs and Ceria NSs significantly reduced the level of reactive oxygen species compared with the control group of SH-SY5Y cells treated with Dulbecco's phosphate-buffered saline. The mRNA expression of superoxide dismutases was also reduced in nanoparticle-treated SH-SY5Y cells, but apparently the degree of mRNA expression decrease was not dependent on the nanoparticle shape. Exposure to ceria nanoparticles also decreased the cyclooxygenase-2 expression, especially prominent in Ceria NR-treated group than that in Ceria NS-treated group. CONCLUSION: Ceria nanoparticles exhibit antioxidant and anti-inflammatory effects in TBI models in vitro. Ceria NRs had better antiinflammatory effect than Ceria NSs, but showed similar antioxidant activity.

Mild Traumatic Brain Injury and Subsequent Acute Pulmonary Inflammatory Response.

OBJECTIVE: The influence of moderate-to-severe traumatic brain injury (TBI) on acute pulmonary injury is well established, but the association between acute pulmonary injury and mild TBI has not been well studied. Here, we evaluated the histological changes and fluctuations in inflammatory markers in the lungs to determine whether an acute pulmonary inflammatory response occurred after mild TBI. METHODS: Mouse models of mild TBI (n=24) were induced via open-head injuries using a stereotaxic impactor. The brain and lungs were examined 6, 24, and 72 hours after injury and compared to sham-operated controls (n=24). Fluoro-Jade B staining and Astra blue and hematoxylin staining were performed to assess cerebral neuronal degeneration and pulmonary histological architecture. Quantitative real-time polymerase chain reaction analysis was done to measure inflammatory cytokines. RESULTS: Increased neuronal degeneration and the mRNA expression of interleukin (IL)-6, tumor necrosis factor (TNF)-α, IL-10, and transforming growth factor (TGF)-ß were observed after mild TBI. The IL-6, TNF-α, and TGF-ß levels in mice with mild TBI were significantly different compared to those of sham-operated mice 24 hours after injury, and this was more pronounced at 72 hours. Mild TBI induced acute pulmonary interstitial edema with cell infiltration and alveolar morphological changes. In particular, a significant infiltration of mast cells was observed. Among the inflammatory cytokines, TNF-α was significantly increased in the lungs at 6 hours, but there was no significant difference 24 and 72 hours after injury. CONCLUSION: Mild TBI induced acute pulmonary interstitial inflammation and alveolar structural changes, which are likely to worsen the patient's prognosis.