Non-apoptotic regulated cell death in Fuchs endothelial corneal dystrophy

Introduction

Fuchs endothelial corneal dystrophy (FECD) is the leading cause of corneal blindness in developed countries. Corneal endothelial cells in FECD are susceptive to oxidative stress, leading to mitochondrial dysfunction and cell death. Oxidative stress causes many forms of cell death including parthanatos, which is characterized by translocation of apoptosis-inducing factor (AIF) to the nucleus with upregulation of poly (ADP-ribose) polymerase 1 (PARP-1) and poly (ADP-ribose) (PAR). Although cell death is an important aspect of FECD, previous reports have often analyzed immortalized cell lines, making the evaluation of cell death difficult. Therefore, we established a new in vitro FECD model to evaluate the pathophysiology of FECD.

Methods

Corneal endothelial cells were derived from disease-specific induced pluripotent stem cells (iPSCs). Hydrogen peroxide (H2O2) was used as a source for oxidative stress to mimic the pathophysiology of FECD. We investigated the responses to oxidative stress and the involvement of parthanatos in FECD-corneal endothelial cells.

Results

Cell death ratio and oxidative stress level were upregulated in FECD with H2O2 treatment compared with non-FECD control, indicating the vulnerability of oxidative stress in FECD. We also found that intracellular PAR, as well as PARP-1 and AIF in the nucleus were upregulated in FECD. Furthermore, PARP inhibition, but not pan-caspase inhibition, rescued cell death, DNA double-strand breaks, mitochondrial membrane potential depolarization and energy depletion, suggesting that cell death was mainly due to parthanatos.

Conclusions

We report that parthanatos may be involved in the pathophysiology of FECD and targeting this cell death pathway may be a potential therapeutic approach for FECD.

A Comprehensive Assessment of Tear-Film-Oriented Diagnosis (TFOD) in a Dacryoadenectomy Dry Eye Model

Tear film instability is a major cause of dry eye disease. In order to treat patients with short tear film breakup time (TBUT)-type dry eye, the development of tear film stabilizing agents is essential. However, the lack of an appropriate animal model of tear film instability has made drug development difficult. Although rabbit dry eye models have been reported in the past, there are only a few reports that focus on tear film instability. Herein, we assessed the tear film stability of a rabbit dry eye model induced by dacryoadenectomy. A clinical evaluation of the ocular surface, interferometry, and histological assessments of the cornea and conjunctiva were performed. Following the removal of the lacrimal glands, TBUT was shortened significantly, with dimple and random breakup patterns prominently observed. Furthermore, the blink rate in this model increased after dacryoadenectomy, suggesting that this model partially captured the phenotypes of human short TBUT-type dry eye and may be useful as an animal model for investigating potential drug candidates.

Annular choroidal detachment following intravitreal aflibercept injection in a patient with nivolumab treatment: a case report

BACKGROUND

To present a novel case that developed annular choroidal detachment after intravitreal anti-vascular endothelial growth factor antibody injection in a patient after immune checkpoint inhibitor treatment.

CASE PRESENTATION

A 58-year-old Japanese man presented visual impairment in the right eye. Ophthalmological examination revealed macular edema in the right eye, which suggested the possibility of age-related macular degeneration. Following the intravitreal aflibercept injection, the annular choroidal detachment was observed in the injected eye. As hypotony or thick sclera was not observed, choroidal detachment seemed to have appeared due to enhanced inflammation by intravitreal injection. The patient had a history of stage IV paranasal cavity cancer and was treated with nivolumab, an immune checkpoint inhibitor. The immune response might have been enhanced due to the use of nivolumab so that intravitreal injection triggered inflammation. Three weeks after sub-tenon injection of triamcinolone acetonide, macular edema and choroidal detachment improved.

CONCLUSIONS

Intravitreal aflibercept injection caused annular choroidal detachment in our patient, presumably because the immune system was activated after nivolumab treatment. To the best of our knowledge, this is the first case report of annular choroidal detachment that developed after intravitreal injection in a patient with a history of nivolumab therapy. With the increasing use of immune checkpoint inhibitors in patients with various cancers, clinicians should be aware of these potentially associated immune-related adverse events.

Micro-incision vitrectomy surgery for primary rhegmatogenous retinal detachments with posterior vitreous detachments in elderly patients: Preoperative characteristics and surgical outcomes

Purpose

To assess the preoperative characteristics and surgical outcomes of using micro-incision vitrectomy surgery (MIVS) to treat RRD with posterior vitreous detachment (PVD) in an older and a younger patient group.

Methods

This retrospective cohort study included 407 eyes from 397 patients with primary RRD with PVD who were consecutively treated in our hospital from February 2016 to February 2020. PVD was diagnosed clinically by the presence of a Weiss ring, or was diagnosed morphologically via optical coherence tomography and subsequently confirmed during surgery. The main outcome measures were preoperative RRD characteristics, best-corrected visual acuity (BCVA), and postoperative complications.

Results

Data were analysed from 55 eyes in the elderly group (age 70 and older), and 352 eyes in the young group (age 69 and younger). There was no significant inter-group difference in the initial reattachment rate. Preoperative characteristics indicated that elderly patients had a significantly lower rate of phakic eyes, shorter mean axial length, lower lattice incidence, and longer time spans from onset to surgery. There were no significant between-group differences in the incidence of the following complications: fibrin formation, intraocular pressure elevation, epi-retinal membrane on the macula, intraocular lens optic capture, proliferative vitreoretinopathy, and vitreous haemorrhage. While the elderly patients had significant postoperative improvements in BCVA, these improvements were significantly lower than those of the younger patients.

Conclusions

This study highlighted the characteristics and surgical outcomes of MIVS in elderly patients with RRD. Although the time from onset to surgery was longer, MIVS still can be performed safely to improve older patients’ postoperative BCVA.

Stimulation of DNA synthesis in trophoblasts and human umbilical vein endothelial cells by hepatocyte growth factor bound to extracellular matrix

Hepatocyte growth factor (HGF) promotes the growth not only of hepatocytes but also of several other types of cells such as cytotrophoblasts and endothelial cells. Recent studies have revealed that HGF is trapped in the extracellular (ECM) matrix through heparan sulphate in vivo, thereby acting as a mitogen for hepatocytes in cooperation with heparan sulphate. In this study, we detected HGF protein in chorionic tissue and placental tissue extracts, and found that HGF and heparan sulphate were co-distributed in the endothelial basement membrane and trophoblast basement membrane on immunohistochemical examination. The rates of DNA synthesis in primary cultured cytotrophoblasts and human umbilical vein endothelial cells (HUVEC) cultured on HGF-bound Matrigeltrade mark were 6-8 times those of control cytotrophoblasts and HUVEC. When Matrigeltrade mark dishes were pretreated with heparinase and heparitinase prior to binding of HGF, stimulation of DNA synthesis was markedly decreased. A considerable decrease in stimulation of DNA synthesis was observed following washing of HGF-bound Matrigeltrade mark with 1 m acetic acid, 1 m NaCl and 0.1 per cent trypsin, but not following treatment with chondroitinase ABC. These observations suggest that HGF can be trapped in ECM in vivo, thereby acting as a mitogen for cytotrophoblasts and placental vein endothelial cells in cooperation with heparan sulphate.

Congenital esophageal atresia with tracheoesophageal fistula occurring in both members of dizygotic twins

The authors present a pair of dizygotic twins with congenital esophageal atresia with tracheoesophageal fistula who underwent successful single-stage surgical repair. To our knowledge, this is the second set of dizygotic twins with this congenital anomaly in the literature.

Functional expression on human trophoblasts of interleukin 4 and interleukin 7 receptor complexes with a common gamma chain

The gamma chain in the high-affinity receptor complex for interleukin 2(IL-2) is used in receptor complexes for IL-4 and IL-7. We examined expression and function of the gamma chain in trophoblast cells. Flow cytometric studies demonstrated that the human placental cell line and choriocarcinoma cell lines expressed the IL-2R gamma chain. None of these cell lines expressed the IL-2R alpha and beta chains, whereas the alpha chains of IL-4R and IL-7R were present. The gamma chain and IL-4R and IL-7R mRNA were detected in human placental trophoblasts by the in situ hybridization method. The release of human chorionic gonadotropin by trophoblasts was accelerated by IL-4 and IL-7 in a concentration-dependent manner. These findings indicate that IL-4 and IL-7 are involved in trophoblast function.

Interleukin 4 (IL-4) blocks the IL-2-induced increased in natural killer activity and DNA synthesis of decidual CD16-CD56bright NK cells by inhibiting expression of the IL-2 receptor alpha, beta, and gamma

The natural killer (NK) activity and DNA synthesis of decidual CD16-CD56bright NK cells were markedly elevated by treatment with interleukin 2 (IL-2). IL-4 did not affect NK activity or DNA synthesis of decidual CD16-CD56bright NK cells, but inhibited the IL-2-induced NK activity and DNA synthesis in a dose-dependent manner. Flow cytometry of decidual mononuclear cells cultured in IL-2 or IL-4 or both IL-2 and IL-4 demonstrated IL-4 inhibition of the expression of the IL-2 receptor alpha (IL-2R alpha), IL-2R beta, and IL-2R gamma on decidual CD16-CD56bright NK cells. This suggests that IL-4 blocks the IL-2-induced NK activity and DNA synthesis of decidual CD16-CD56bright NK cells by inhibiting the expression of IL-2R alpha, IL-2R beta, and IL-2R gamma.

Hepatocyte growth factor promotes the growth of cytotrophoblasts by the paracrine mechanism

Both placental and decidual tissues contained extractable HGF, the former HGF level (31.4 +/- 23.4 ng/mg total protein) being approximately 30 times the latter HGF level. When the localization of HGF protein and HGF mRNA in placental tissues was examined by immunohistological staining and in situ hybridization, HGF protein and HGF mRNA were detected in the mesenchymal cells of the placenta, but were absent in the cytotrophoblast and syncytiotrophoblast. Although c-met protein was expressed in the cytotrophoblast, this receptor was not detectable in the syncytiotrophoblast by immunohistochemical methods. c-met mRNA was detected in placental cell line (tPA30-1) and 4 choriocarcinoma cell lines (BeWo, Jar, Jeg-3, and NUC-1), but HGF mRNA was absent in these cells. When cytotrophoblast cells were cultured in a serum-free medium in the presence of HGF, their DNA synthesis was enhanced depending on the HGF concentration, although human placental lactogen secretion itself was not affected by HGF. These results demonstrated that HGF promotes the growth of the cytotrophoblast by the paracrine mechanism, although it does not serve as a placental differentiation factor.

Localization of stem cell factor (SCF) and c-kit mRNA in human placental tissue and biological effects of SCF on DNA synthesis in primary cultured cytotrophoblasts

The supernatant of homogenized human placental tissues at early and late stages of pregnancy were found to contain 40-100 pg of stem cell factor (SCF)/mg of total protein by enzyme linked immunosorbent assay. When the SCF mRNA expression was examined by reverse transcriptase-polymerase chain reaction (RT-PCR), the secretory type and membrane-bound type SCF mRNA were detected in the human placental tissues in the early stages of pregnancy and in a human placental cell line;tPA30-1 cells. However, the secretory type SCF mRNA was predominant and membrane-bound type SCF mRNA was absent or very weak in the term placental tissues. When the distribution of SCF mRNA and c-kit mRNA in the placental tissues was examined by in situ hybridization, SCF mRNA was detected in the cytotrophoblast, the intermediate trophoblastic cell column and the stromal cells, while c-kit mRNA was detected in the cytotrophoblast and the intermediate trophoblastic cell column. Both c-kit and SCF mRNA were absent or very weak in the syncytiotrophoblasts. The supernatant of primary cultured cytotrophoblasts and tPA30-1 cells were found to contain SCF. In cytotrophoblasts in the early stage of pregnancy cultured in the presence of recombinant human secretory type SCF, DNA synthesis was increased depending on the SCF concentration. These findings indicate that SCF is a cytokine which promotes the growth of placental cells by the autocrine and paracrine mechanism.

Detection and localization of interleukin-8 mRNA and protein in human placenta and decidual tissues

It has been reported that interleukin-8 (IL-8) is secreted from the placental and decidual tissues and that IL-8 levels in the amniotic fluids are significantly elevated by chorioamnionitis or labor pain. The present study was aimed at defining the localization of IL-8 mRNA as well as IL-8 protein at the feto-maternal interface using in situ hybridization and immunohistochemical staining. Both IL-8 mRNA and protein were localized in cytotrophoblast, syncytiotrophoblast and Hofbauer cells of the placenta, decidual stromal cells, decidual lymphocytes and endometrial gland cells. IL-8 secretion from glandular cells has not previously been reported. In addition, we confirmed IL-8 mRNA expression and secretion of IL-8 by an endometrial cancer cell line (Ishikawa) using the reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) methods, respectively.

[The importance of CA125 immunohistochemical staining in patients with ovarian cancer]

CA125 has been regarded as a marker for hyperplastic conditions, such as endometriosis or infectious peritonitis. A high serum CA125 level should therefore be carefully evaluated clinically. We measured CA125 levels in sera and ascites as well as the volume of ascites in patients with ovarian cancer, and also performed immunohistochemical staining of their primary tumors for CA125.

RESULTS

1. The tumor positive rate for CA125 was 49% immunohistochemically. 2. In the patients whose tumors were positive for CA125, the serum CA125 level was 3,309 U/ml and the ascitic fluid CA125 level was 23,621 U/ml. In the patients whose tumors were negative for CA125 the serum and ascitic fluid levels of CA125 were 264 U/ml and 1,919 U/ml, respectively. Both serum and ascitic fluid CA125 levels were significantly higher in the CA125-positive tumor group than in the CA125-negative tumor group (t-test: both p < 0.05). 3. In both groups, the serum CA125 level increased with advancing stage. 4. There was a positive correlation between the serum CA125 level and the volume of ascites in both groups. CA125-positive tumor group: Y = 1.02X + 0.38, r = 0.90, r2 = 0.81 (p < 0.0001) CA125-negative tumor group: Y = 0.34X + 1.35, r = 0.51, r2 = 0.26 (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Interleukin-8 production by CD16-CD56bright natural killer cells in the human early pregnancy decidua

Decidual CD16-CD56bright natural killer (NK) cells were sorted from the decidual mononuclear cells (MNC) at the early pregnancy using a fluorescence activated cell sortor. The CD16-CD56bright NK cell population occupies a major population in the decidual MNC, in contrast to a very small population (< 1%) in the peripheral blood MNC. These decidual CD16-CD56bright NK cells produced a large amount of IL-8, i. e., mean of 96.7 +/- 19.8 ng/ml in the 24 hr-cultured supernatants without any stimulant, which was comparable to the IL-8 production by LPS-stimulated peripheral blood MNC. Most of the IL-8 was ascribable to the production from decidual CD16-CD56bright NK cells. Intracytoplasmic IL-8 in the decidual CD56bright NK cells was also detected by flow cytometry. RT-PCR methods confirmed IL-8 mRNA expression in this population, while no or very scarce expression of IL-1 alpha and IL-1 beta mRNA was observed. The present study is a first observation revealing that decidual CD16-CD56bright NK cells express IL-8 mRNA and produce IL-8.

The effect of interleukin 2 and transforming growth factor-beta 2 (TGF-beta 2) on the proliferation and natural killer activity of decidual CD16- CD56bright natural killer cells

The present study, using flow cytometry, demonstrated that CD16- CD56bright natural killer (NK) cells, which are abundant in the decidua, have both interleukin-2 receptor alpha (IL-2R alpha) and interleukin-2 receptor beta (IL-2R beta). The NK activity and DNA synthesis of CD16- CD56bright NK cells were markedly elevated even by treatment with small amounts of IL-2. These results indicate that decidual CD16- CD56bright NK cells possess a high-affinity receptor for IL-2. Transforming growth factor-beta 2 (TGF-beta 2), which is contained in the decidua and is thought to serve as a major immunosuppressive factor, reduced the NK activity of decidual CD16- CD56bright NK cells, but it hardly affected the IL-2-induced augmentation of the NK activity or DNA synthesis of decidual CD16- CD56bright NK cells. The conclusion has therefore been reached that once IL-2 is produced in the decidua, the IL-2-induced potentiation of the NK activity of decidual CD16- CD56bright NK cells cannot be suppressed by TGF-beta 2.

Endocrine and hemodynamic changes during liver surgery in patients with compensated liver cirrhosis

The purpose of this study was to determine hormonal levels in compensated liver cirrhotic patients under general anesthesia before and after liver surgery. We measured plasma norepinephrine, epinephrine, arginine vasopressin, and aldosterone levels and renin activity in non-cirrhotic and compensated cirrhotic patients undergoing liver resection after induction of anesthesia but before skin incision and after the end of operation but before discontinuation of nitrous oxide. We simultaneously measured hemodynamic variables. Plasma levels of norepinephrine (P < 0.001), epinephrine (P < 0.001), arginine vasopressin (P < 0.05), renin (P < 0.05) and aldosterone (P < 0.001) significantly increased after completion of surgery compared with those before incision in both groups. There was a significant positive correlation between plasma renin and aldosterone (r = 0.56, P < 0.01) levels in non-cirrhotics, but no correlation was observed in cirrhotics; and there was a significant positive correlation between plasma norepinephrine and arginine vasopressin (r = 0.45, P < 0.05) levels in non-cirrhotics, but no correlation in cirrhotics. Cardiac index and arterial pressure increased after the end of operation (P < 0.05). This increase after the operation was the same between cirrhotic and non-cirrhotic groups. There were no changes in heart rate, mean pulmonary arterial pressure, and pulmonary capillary wedge pressure after the end of operation. We conclude that hemodynamic and endocrinological changes were similar between compensated cirrhotic patients and non-cirrhotic patients during liver surgery. Endocrine changes might partly explain the hemodynamic changes during surgery.

Hemorrheological effects of colloidal plasma substitutes infusion. A comparative study

Our objective was to investigate experimentally the easily overlooked effect of the clinical use of colloidal plasma substitutes on tissue perfusion. The experimental animals were dogs, and the study was carried out using several independent rheological experimental methods. The following are the principal findings: 1) Based on the observations made under a microscope, the stability of blood suspensions was best maintained by dextran-40 (Dex 40) and hydroxyethyl starch (HES0.55; Hespander), both of which cause little rouleaux formation by erythrocytes. In addition, the electronegativity of the erythrocyte membrane was simultaneously elevated. 2) The blood viscosity was greatly affected by the hematocrit and the serum protein concentration. 3) At a high shear rate, the blood viscosity among these colloidal plasma substitutes showed no great difference after infusion; in contrast, at a low shear rate, the blood viscosity after infusion of Dex 40 or HES0.55 was lower than after other substitutes. 4) The ratio of the viscosity at a low shear rate to the viscosity at a high shear rate is more significant and useful as a clinical indicator. On the basis of the preceding findings, Dex 40 and HES0.55 were generally superior to the other substitutes, especially HES0.55.