Involvement of MAPKs in ICAM-1 Expression in Glomerular Endothelial Cells in Diabetic Nephropathy

Inflammatory processes are involved in the pathogenesis of diabetic nephropathy. The aim of this study was to clarify the role of mitogen-activated protein kinase (MAPK) pathways for induction of intercellular adhesion molecule-1 (ICAM-1) expression in glomerular endothelial cells under diabetic conditions. We examined the expression of ICAM-1 in the kidneys of experimental diabetic rats. Human glomerular endothelial cells (GE cells) were exposed to normal glucose concentration, high glucose concentration (HG), or high mannitol concentration (HM), and then the expression of the ICAM-1 protein and the phosphorylation of the 3 subfamilies of mitogen-activated protein kinase (MAPK) were determined using Western blot analysis. Next, to evaluate the involvement of MAPKs in HG- or HM-induced ICAM-1 expression, we preincubated GE cells with the inhibitors for ERK, p38 or JNK 1h prior to the application of glucose or mannitol. Expression of ICAM-1 was increased in the glomeruli of diabetic rats. Both HG and HM induced ICAM-1 expression and phosphorylation of ERK1/2, p38 and JNK in GE cells. Expression of ICAM-1 was significantly attenuated by inhibitors of ERK, p38 and JNK. We conclude that activation of ERK1/2, p38 and JNK cascades may be involved in ICAM-1 expression in glomerular endothelial cells under diabetic conditions

Three-dimensional architecture of rat glomerular basement membrane by ultra-high resolution scanning electron microscopy.

We demonstrated the ultrastructure of rat glomerular basement membrane (GBM) by ultra-high resolution scanning electron microscopy. GBM prepared by sonication methods and conductive-staining could be observed without metal coating at magnifications as high as 400,000 times. The GBM showed an irregular meshwork structure composed of various strands and pores. The width of the strands ranged from 6 to 15 nm, and the diameter of pores ranged from 6 to 50 nm. The present study confirmed our molecular sieve theory of the basement membrane.</p

FKBP5 regulation on anti-PD-1 therapy

Background. Antitumor therapies targeting programmed cell death-1 (PD-1) or its ligand-1 (PD-L1) are used in various cancers. However, in glioblastoma (GBM), the expression of PD-L1 varies between patients, and the relationship between this variation and the efficacy of anti-PD-1 antibody therapy remains unclear. High expression levels of PD-L1 affect the proliferation and invasiveness of GBM cells. As COX-2 modulates PD-L1 expression in cancer cells, we tested the hypothesis that the COX-2 inhibitor celecoxib potentiates anti-PD-1 antibody treatment via the downregulation of PD-L1. Methods. Six-week-old male C57BL/6 mice injected with murine glioma stem cells (GSCs) were randomly divided into four groups treated with vehicle, celecoxib, anti-PD-1 antibody, or celecoxib plus anti-PD-1 antibody and the antitumor effects of these treatments were assessed. To verify the mechanisms underlying these effects, murine GSCs and human GBM cells were studied in vitro. Results. Compared with that with each single treatment, the combination of celecoxib and anti-PD-1 antibody treatment significantly decreased tumor volume and prolonged survival. The high expression of PD-L1 was decreased by celecoxib in the glioma model injected with murine GSCs, cultured murine GSCs, and cultured human GBM cells. This reduction was associated with post-transcriptional regulation of the co-chaperone FK506-binding protein 5 (FKBP5). Conclusions. Combination therapy with anti-PD-1 antibody plus celecoxib might be a promising therapeutic strategy to target PD-L1 in glioblastoma. The downregulation of highly-expressed PD-L1 via FKBP5, induced by celecoxib, could play a role in its antitumor effects

Could clazosentan, first approved in Japan, improve neurological prognosis after subarachnoid hemorrhage in combination with modified water-electrolyte management?

An aneurysmal subarachnoid hemorrhage (aSAH) is a devastating event associated with a high mortality and morbidity rate. Though numerous medications are used to prevent cerebral vasospasm and vasospasm-related cerebral infarction after aSAH, no effective pharmacological treatment has been established. Clazosentan, a highly selective endothelin receptor type A antagonist, was approved for use in Japan in April 2022 based on results of two pivotal randomized, placebo-controlled phase 3 studies (JapicCTI-163369, JapicCTI-163368). These studies indicated that clazosentan significantly reduced the incidence of vasospasm-related morbidity and all-cause mortality after aneurysm coiling and clipping. Clazosentan is thus expected to become a “game changer” for improving the neurological prognosis after aSAH. However, other reports indicate that even when clazosentan or nimodipine are administered for prophylaxis against delayed neurological decline, patients treated with increased colloid administration or hypertonic saline (3% sodium chloride) load exhibit poor functional outcome and higher mortality, suggesting that extra fluid and sodium derived from prophylactic colloid administration contribute to negative outcomes after aSAH. Pharmacological treatments such as clazosentan in addition to perioperative management involving delivery of less water and sodium might be crucial for achieving better outcomes than conventional therapy. Based on a literature review, we present here the future perspectives regarding clazosentan and the necessity for modifying management of the water-electrolyte balance by focusing on endothelin-1 and blood–brain barrier disruption

Time-dependent and site-dependent morphological changes in rupture-prone arteries : ovariectomized rat intracranial aneurysm model

OBJECTIVE The pathogenesis of intracranial aneurysm rupture remains unclear. Because it is difficult to study the time course of human aneurysms and most unruptured aneurysms are stable, animal models are used to investigate the characteristics of intracranial aneurysms. The authors have newly established a rat intracranial aneurysm rupture model that features site-specific ruptured and unruptured aneurysms. In the present study the authors examined the time course of changes in the vascular morphology to clarify the mechanisms leading to rupture. METHODS Ten-week-old female Sprague-Dawley rats were subjected to hemodynamic changes, hypertension, and ovariectomy. Morphological changes in rupture-prone intracranial arteries were examined under a scanning electron microscope and the association with vascular degradation molecules was investigated. RESULTS At 2–6 weeks after aneurysm induction, morphological changes and rupture were mainly observed at the posterior cerebral artery; at 7–12 weeks they were seen at the anterior Willis circle including the anterior communicating artery. No aneurysms at the anterior cerebral artery–olfactory artery bifurcation ruptured, suggesting that the inception of morphological changes is site dependent. On week 6, the messenger RNA level of matrix metalloproteinase–9, interleukin-1β, and the ratio of matrix metalloproteinase–9 to the tissue inhibitor of metalloproteinase–2 was significantly higher at the posterior cerebral artery, but not at the anterior communicating artery, of rats with aneurysms than in sham-operated rats. These findings suggest that aneurysm rupture is attributable to significant morphological changes and an increase in degradation molecules. CONCLUSIONS Time-dependent and site-dependent morphological changes and the level of degradation molecules may be indicative of the vulnerability of aneurysms to rupture

Progression to In-Hospital Ischemic Stroke

Background and Purpose: Little attention has been paid to the pathogenesis of in-hospital stroke, despite poor outcomes and a longer time from stroke onset to treatment. We studied the pathophysiology and biomarkers for detecting patients who progress to in-hospital ischemic stroke (IHS). Methods: Seventy-nine patients with IHS were sequentially recruited in the period 2011–2017. Their characteristics, care, and outcomes were compared with 933 patients who had an out-of-hospital ischemic stroke (OHS) using a prospectively collected database of the Tokushima University Stroke Registry. Results: Active cancer and coronary artery disease were more prevalent in patients with IHS than in those with OHS (53.2 and 27.8% vs. 2.0 and 10.9%, respectively; p < 0.001), the median onset-to-evaluation time was longer (300 vs. 240 min; p = 0.015), and the undetermined etiology was significantly higher (36.7 vs. 2.4%; p < 0.001). Although there was no significant difference in stroke severity at onset between the groups, patients with IHS had higher modified Rankin Scale (mRS) scores (3–6) at discharge (67.1 vs. 50.3%; p = 0.004) and rates of death during hospitalization (16.5 vs. 2.9%; p < 0.001). D-dimer (5.8 vs. 0.8 µg/mL; p < 0.001) and fibrinogen (532 vs. 430 mg/dL; p = 0.014) plasma levels at the time of onset were significantly higher in patients with IHS after propensity score matching. Multivariate logistic regression analysis revealed that active cancer (odds ratio [OR] 2.30; 95% confidence interval [CI] 1.26–4.20), prestroke mRS scores 3–5 (OR 6.78; 95% CI 3.96–11.61), female sex (OR 1.57; 95% CI 1.19–2.08), and age ≥75 years (OR 2.36; 95% CI 1.80–3.08) were associated with poor outcomes. Conclusions: Patients with IHS had poorer outcomes than those with OHS because of a higher prevalence of active cancer and functional dependence before stroke onset. Elevated plasma levels of D-dimer and fibrinogen, especially with active cancer, can help identify patients who are at a higher risk of progression to IHS

RUPTURED CEREBRAL ANEURYSMS AND SEVERE PD

BACKGROUND: The pathophysiology of subarachnoid hemorrhages (SAHs) due to ruptured intracranial aneurysms (IAs) remains unclear.Although a relationship between SAHs and periodontal disease (PD) has been suggested, the mechanism requires clarification. OBJECTIVE: To evaluate the relationship between PD and SAHs and to identify periodontal pathogens associated with SAHs. METHODS: This prospective study included consecutive patients with ruptured (n = 11) and unruptured (n = 14) IAs and healthy controls (n = 8). The plasma and plaque subgingival bacterial deoxyribonucleic acid (DNA) levels in PD were evaluated by a dentist using the Community Periodontal Index of Treatment Needs (CPITN). Plasma levels of matrix metalloproteinase (MMP-9), tissue inhibitors of matrix metalloproteinase (TIMP2), and procollagen I were analyzed. RESULTS: Patients with ruptured IAs, had significantly higher CPITN scores than the controls, suggesting that ruptured IAs were associated with severe PD. Although no rupture-specific bacteria were identified, the positive rate of plaque subgingival bacterial DNA was significantly higher in patients with severe PD than in those without severe PD. Multivariate logistic regression analysis indicated that bleeding on probing (BOP)was associated with ruptured IAs (odds ratio, 1.10; 95% confidence interval 1.04–1.20; P = .0001). BOP was positively associated with plasma MMP-9 levels and a disequilibrium in the MMP-9/TIMP2 ratio. BOP was negatively correlated with plasma procollagen I levels (P < .05, for each). This suggested that local inflammation with severe PD might have systemic effects and lead to ruptured IAs. CONCLUSION: Disequilibrium of plasma protease/anti-protease associated with a high BOP rate in severe PD may be attributable to IA rupture

Isotope production in proton-, deuteron-, and carbon-induced reactions on Nb 93 at 113 MeV/nucleon

Isotope-production cross sections for p-, d-, and C-induced spallation reactions on Nb93 at 113 MeV/nucleon were measured using the inverse-kinematics method employing secondary targets of CH2, CD2, and C. The measured cross sections for Mo90, Nb90, Y86,88 produced by p-induced reactions were found to be consistent with those measured by the conventional activation method. We performed benchmark tests of the reaction models INCL-4.6, JQMD, and JQMD-2.0 implemented in the Particle and Heavy Ion Transport code System (PHITS) and of the nuclear data libraries JENDL-4.0/HE, TENDL-2017, and ENDF/B-VIII.0. The model calculations also showed generally good agreement with the measured isotope-production cross sections for p-, d-, and C-induced reactions. It also turns out that, among the three nuclear data libraries, JENDL-4.0/HE provides the best agreement with the measured data for the p-induced reactions. We compared the present Nb93 data with the Zr93 data, that were measured previously by the same inverse kinematics method (Kawase et al., Prog. Theor. Exp. Phys. 2017, 093D03 (2017)2050-391110.1093/ptep/ptx110), with particular attention to the effect of neutron-shell closure on isotope production in p- and d-induced spallation reactions. The isotopic distributions of the measured production cross sections in the Zr93 data showed noticeable jumps at neutron number N=50 in the isotopic chains of ΔZ=0 and -1, whereas no such jump appeared in isotopic chain of ΔZ=0 in the Nb93 data. From INCL-4.6 + GEM calculations, we found that the jump formed in the evaporation process is smeared out by the intranuclear cascade component in Nb91 produced by the Nb93(p,p2n) and (d,d2n) reactions on Nb93. Moreover, for Nb93, the distribution of the element-production cross sections as a function of the change in proton number ΔZ is shifted to smaller ΔZ than for Zr93, because the excited Nb prefragments generated by the cascade process are more likely to emit protons than the excited Zr prefragments, due to the smaller proton-separation energies of the Nb isotopes

Coulomb breakup reactions of 93,94 Zr in inverse kinematics

Coulomb breakup reactions of 93,94 Zr have been studied in inverse kinematics at incident beam energies of about 200 MeV/nucleon in order to evaluate neutron capture reaction methods. The 93 Zr(n,γ) 94 Zr reaction is particularly important as a candidate nuclear transmutation reaction for the long-lived fission product 93 Zr in nuclear power plants. One- and two-neutron removal cross sections on Pb and C targets were measured to deduce the inclusive Coulomb breakup cross sections, 375 ± 29 (stat.) ± 30 (syst.) and 403 ± 26 (stat.) ± 31 (syst.) mb for 93 Zr and 94 Zr, respectively. The results are compared with estimates using the standard Lorentzian model and microscopic calculations. The results reveal a possible contribution of the pygmy dipole resonance or giant quadrupole resonance in the Coulomb breakup reactions of 94 Zr