Macroglia-microglia interactions via TSPO signaling regulates microglial activation in the mouse retina

Chronic retinal inflammation in the form of activated microglia and macrophages are implicated in the etiology of neurodegenerative diseases of the retina, including age-related macular degeneration, diabetic retinopathy, and glaucoma. However, molecular biomarkers and targeted therapies for immune cell activation in these disorders are currently lacking. To address this, we investigated the involvement and role of translocator protein (TSPO), a biomarker of microglial and astrocyte gliosis in brain degeneration, in the context of retinal inflammation. Here, we find that TSPO is acutely and specifically upregulated in retinal microglia in separate mouse models of retinal inflammation and injury. Concomitantly, its endogenous ligand, diazepam-binding inhibitor (DBI), is upregulated in the macroglia of the mouse retina such as astrocytes and Müller cells. In addition, we discover that TSPO-mediated signaling in microglia via DBI-derived ligands negatively regulates features of microglial activation, including reactive oxygen species production, TNF-α expression and secretion, and microglial proliferation. The inducibility and effects of DBI-TSPO signaling in the retina reveal a mechanism of coordinated macroglia-microglia interactions, the function of which is to limit the magnitude of inflammatory responses after their initiation, facilitating a return to baseline quiescence. Our results indicate that TSPO is a promising molecular marker for imaging inflammatory cell activation in the retina and highlight DBI-TSPO signaling as a potential target for immodulatory therapies.

Acyl-CoA-Binding Protein Drives Glioblastoma Tumorigenesis by Sustaining Fatty Acid Oxidation

Glioblastoma multiforme (GBM) undergoes metabolic reprogramming to meet the high ATP and anabolic demands of the tumor cells. However, the role of fatty acid oxidation (FAO) and its regulators in the GBM context has been largely unknown. Here, we show that the neural stem cell pro-proliferative factor acyl-CoA-binding protein (ACBP, also known as DBI) is highly expressed in GBM, and by binding to acyl-CoAs, it cell-autonomously maintains high proliferation rates, promoting tumor growth and poor survival in several preclinical models. Mechanistic experiments using ACBP-acyl-CoA binding affinity variants and pharmacological FAO modulators suggest that ACBP supports tumor growth by controlling the availability of long-chain fatty acyl-CoAs to mitochondria, promoting FAO in GBM. Thus, our findings uncover a critical link between lipid metabolism and GBM progression established by ACBP and offer a potential therapeutic strategy for an effective anti-proliferative metabolic management of GBM.

Toll-like receptor-4 pathway as a possible molecular mechanism for brain injuries after subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is known as an acute catastrophic neurological disease that continues to be a serious and significant health problem worldwide. The mechanisms contributing to brain injury after SAH remain unclear despite decades of study focusing on early brain injury (EBI) and delayed brain injury (DBI). Neuroinflammation is a well-recognized consequence of SAH and may be responsible for EBI, cerebral vasospasm, and DBI. Toll-like receptors (TLRs) play a crucial role in the inflammatory response by recognizing damage-associated molecular patterns derived from the SAH. TLR4 is the most studied Toll-like receptor and is widely expressed in the central nervous system (CNS). It can be activated by the extravasated blood components in myeloid differentiation primary response-88/Toll/interleukin-1 receptor-domain-containing adapter-inducing interferon-β (MyD88/TRIF)-dependent pathway after SAH. Transcription factors, such as nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK) and interferon regulatory factor (IRF), that regulate the expression of proinflammatory cytokine genes are initiated by the activation of TLR4, which cause the brain damage after SAH. TLR4 may therefore be a useful therapeutic target for overcoming EBI and DBI in post-SAH neuroinflammation, thereby improving SAH outcome. In the present review, we summarized recent findings from basic and clinical studies of SAH, with a primary focus on the biological characteristics and functions of TLR4 and discussed the mechanisms associated with TLR4 signaling pathway in EBI and DBI following SAH.

A Meta-Analysis of the Impact of Professional Development on Teachers' Knowledge, Skill, and Self-Efficacy in Data-Based Decision-Making

The purpose of this review was to synthesize research on the effect of professional development (PD) targeting data-based decision-making processes on teachers' knowledge, skills, and self-efficacy related to curriculum-based measurement (CBM) and data-based decision-making (DBDM). To be eligible for this review, studies had to (a) be published in English, (b) include in-service or pre-service K-12 teachers as participants, (c) use an empirical group design, and (d) include sufficient data to calculate an effect size for teacher outcome variables. The mean effect of DBDM PD on teacher outcomes was g = 0.57 (p < .001). This effect was not moderated by study quality. These results must be viewed through the lens of significant heterogeneity in effects across included studies, which could not be explained by follow-up sensitivity analyses. In addition, the experimental studies included in this review occurred under ideal, researcher-supported conditions, which impacts the generalizability of the effects of DBDM PD in practice. Implications for research and practice are discussed.

Disorder of Executive Function of the Brain after Head Injury and Mild Traumatic Brain Injury - Neuroimaging and Diagnostic Criteria for Implementation of Administrative Support in Japan

The diagnotic criteria for disorder of the executive function of the brain (DEFB) as a syndrome of sequela were administratively established (ad-DEFB) in Japan in 2006 to support disabled patients whose impairment, limited to cognition (memory, attention, execution, and behavior), emerges after organic brain injuries regardless of physical deficits. However, some patients suffering from traumatic brain injury (TBI) have been excluded from receiving medico-social services. In particular, this tendency is more prominent in patients with mild TBI because no lesions are apparent on conventional computed tomography (CT) or magnetic resonance imaging (MRI) in the chronic phase. Recent development of new MRI neuroimaging modalities and positron emission tomography (PET) imaging makes it possible to detect regions of minute organic lesions and metabolic dysfunction in the brain where organic lesions may be absent or cannot be detected on conventional CT or MRI. In this review, we discuss diagnostic criteria for mild TBI and ad-DEFB, the relationship between the two disorders, characteristic neuroimaging [(MRI and 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET)] of diffuse brain injury including cerebral concussion, which is the principal cause of mild TBI, and suggested pathological mechanisms of ad-DEFB in DBI.

Enhancing the compatibility and performance of poly (lactic acid) and thermoplastic polyolefin elastomer blends through a dual compatibilization strategy

Application of biodegradable polylactic acid (PLA) is limited by its poor toughness. This research focuses on modifying PLA using thermoplastic elastomers (TPO), primarily due to their dual advantages of enhancing performance and reducing application costs. Two thermoplastic polyolefin elastomers (TPO) (NS06, Versify2300) were blended to prepare a superior elastomer TPO(NV) (NS06:Versify2300 = 80:20). This improved TPO(NV) was then used as a toughening agent to enhance the toughness of polylactic acid (PLA). To enhance the compatibility between PLA and TPO(NV), TPO(NV)-g-(GMA-co-St) graft copolymer and dibutyl itaconate (DBI) were introduced into the PLA/TPO(NV) blend system. The effects of different compatibilizers on the compatibility, crystallization behavior, rheological properties, mechanical properties, and microstructure of the PLA/TPO(NV) blends were systematically studied. The results indicated that glycidyl methacrylate (GMA) and styrene (St) were successfully grafted onto the TPO(NV) molecular chains. The epoxy groups in GMA within the graft copolymer could react with the end groups of the PLA resin, while the double bonds in DBI could react with the main chains of either PLA or TPO(NV) elastomer. This effectively connected the PLA and TPO(NV) molecular chains, collectively enhancing the compatibility between TPO(NV) elastomer and PLA. The non-isothermal crystallization ability of TPO(NV) decreased after blending with PLA, and this effect was further amplified with the introduction of the TPO(NV)-g-(GMA-co-St) graft copolymer or DBI. However, the plasticizing effect of DBI increased the mobility of the polymer molecular chains, thereby enhancing the crystallization ability. Therefore, when DBI was used alone to enhance the compatibility of PLA/TPO(NV) blends, the crystallinity of the blend did not change significantly. In contrast, when the TPO(NV)-g-(GMA-co-St) graft copolymer was used alone or in combination with DBI, the crystallinity of the blend decreased significantly. Mechanical property tests indicated that the addition of either the TPO(NV)-g-(GMA-co-St) graft copolymer or DBI improved the compatibility of PLA/TPO(NV) blends, thereby enhancing their mechanical properties. However, the combined addition of both the TPO(NV)-g-(GMA-co-St) graft copolymer and DBI resulted in a more pronounced effect. The notched impact strength and elongation at break reached optimal values, which were 1.9 times and 10.4 times those of the PLA/TPO(NV) blend, respectively. At this point, the fracture surface of the blend exhibited significant plastic flow, indicating characteristics of ductile fracture.