Contribution of MLKL to the development of doxorubicin-induced cardiomyopathy and its amelioration by rapamycin.

Necroptosis, necrosis characterized by RIPK3-MLKL activation, has been proposed as a mechanism of doxorubicin (DOX)-induced cardiomyopathy. We showed that rapamycin, an mTORC1 inhibitor, attenuates cardiomyocyte necroptosis. Here we examined role of MLKL in DOX-induced myocardial damage and protective effects of rapamycin. Cardiomyopathy was induced in mice by intraperitoneal injections of DOX (10 mg/kg, every other day) and followed for 7 days. DOX-treated mice showed a significant decline in LVEF assessed by cardiac MRI (45.5 ± 5.1% vs. 65.4 ± 4.2%), reduction in overall survival rates, and increases in myocardial RIPK3 and MLKL expression compared with those in vehicle-treated mice, and those changes were prevented by administration of rapamycin (0.25 mg/kg) before DOX injection. In immunohistochemical analyses, p-MLKL signals were detected in the cardiomyocytes of DOX-treated mice, and the signals were reduced by rapamycin. Mlkl+/- and Mlkl-/- mice were similarly resistant to DOX-induced cardiac dysfunction, indicating that a modest reduction in MLKL level is sufficient to prevent the development of DOX-induced cardiomyopathy. However, evidence of cardiomyocyte necrosis assessed by C9 immunostaining, presence of replacement fibrosis, and electron microscopic analyses was negligible in the myocardium of DOX-treated mice. Thus, MLKL-mediated signaling contributes to DOX-induced cardiac dysfunction primarily by a necrosis-independent mechanism, which is inhibitable by rapamycin.

Fatty Acid-Binding Protein 4-Mediated Regulation Is Pivotally Involved in Retinal Pathophysiology: A Review.

Fatty acid-binding proteins (FABPs), a family of lipid chaperone molecules that are involved in intracellular lipid transportation to specific cellular compartments, stimulate lipid-associated responses such as biological signaling, membrane synthesis, transcriptional regulation, and lipid synthesis. Previous studies have shown that FABP4, a member of this family of proteins that are expressed in adipocytes and macrophages, plays pivotal roles in the pathogenesis of various cardiovascular and metabolic diseases, including diabetes mellitus (DM) and hypertension (HT). Since significant increases in the serum levels of FABP4 were detected in those patients, FABP4 has been identified as a crucial biomarker for these systemic diseases. In addition, in the field of ophthalmology, our group found that intraocular levels of FABP4 (ioFABP4) and free fatty acids (ioFFA) were substantially elevated in patients with retinal vascular diseases (RVDs) including proliferative diabetic retinopathy (PDR) and retinal vein occlusion (RVO), for which DM and HT are also recognized as significant risk factors. Recent studies have also revealed that ioFABP4 plays important roles in both retinal physiology and pathogenesis, and the results of these studies have suggested potential molecular targets for retinal diseases that might lead to future new therapeutic strategies.

Inhibition of mTOR differently modulates planar and subepithelial fibrogenesis in human conjunctival fibroblasts.

PURPOSE: In the current investigation, the effects of the mTOR inhibitors, Rapa and Torin1 on the TGF-ß2-induced conjunctival fibrogenesis were studied. STUDY DESIGN: Experimental research. METHODS: 2D and 3D cultures of HconF were subjected to the following analyses; (1) planar proliferation evaluated by TEER (2D), (2) Seahorse metabolic analyses (2D), (3) subepithelial proliferation evaluated by the 3D spheroids' size and hardness, and (4) the mRNA expression of ECM proteins and their regulators (2D and 3D). RESULT: Rapa or Torin1 both significantly increased planar proliferation in the non-TGF-ß2-treated 2D HconF cells, but in the TGF-ß2-treated cells, this proliferation was inhibited by Rapa and enhanced by Torin1. Although Rapa or Torin1 did not affect cellular metabolism in the non-TGF-ß2-treated HconF cells, mTOR inhibitors significantly decreased and increased the mitochondrial respiration and the glycolytic capacity, respectively, under conditions of TGF-ß2-induced fibrogenesis. Subepithelial proliferation, as evidenced by the hardness of the 3D spheroids, was markedly down-regulated by both Rapa and Torin1 independent of TGF-ß2. The mRNA expressions of several ECM molecules and their regulators fluctuated in the cases of 2D vs 3D and TGF-ß2 untreated vs treated cultures. CONCLUSION: The present findings indicate that mTOR inhibitors have the ability to increase and to reduce planar and subepithelial proliferation in HconF cells, depending on the inhibitor being used.

High Intraocular Pressure Is Independently Associated With New-Onset Systemic Hypertension Over a 10-Year Period.

BACKGROUND: Systemic hypertension (HT) is associated with the development of increased intraocular pressure (IOP), a risk factor for glaucoma. However, it remains unclear whether high IOP is a risk factor for HT.Methods and Results: We investigated 7,487 Japanese individuals (4,714 men, 2,773 women; mean [±SD] age 49±9 years) who underwent annual health checkups in 2006. Over the 10-year follow-up period, 1,232 (24.3%) men and 370 (11.5%) women developed new-onset HT, defined as initiation of antihypertensive drug treatment or blood pressure ≥140/90 mmHg. After dividing IOP into tertiles (T1-T3), Cox proportional hazards analysis (adjusted for age, sex, systolic blood pressure, obesity, current smoking, alcohol consumption, family history of HT, estimated glomerular filtration rate, and diabetes and dyslipidemia diagnoses at baseline) revealed a significantly higher risk of newly developed HT in T3 (IOP ≥14 mmHg; hazard ratio 1.14; 95% confidence interval 1.01-1.29; P=0.038) using T1 (IOP ≤11 mmHg) as the reference group. There was no significant interaction between sex and IOP tertile (P=0.153). A restricted cubic spline model showed a gradual but robust increase in the hazard ratio for new-onset HT with increasing IOP. CONCLUSIONS: High IOP is an independent risk factor for the development of HT over a 10-year period.

Lysophosphatidic Acid Modulates TGF-ß2-Induced Biological Phenotype in Human Conjunctival Fibroblasts.

BACKGROUND: Although lysophosphatidic acid (LPA) is known to have multiple pathophysiological roles, its contributions to ocular tissues, especially conjunctival fibrogenesis, remain to be elucidated. METHODS: To study this issue, the effects of LPA on transforming growth factor-ß2 (TGF-ß2)-induced fibrogenesis of two-dimensional (2D) and three-dimensional (3D) cultures of human conjunctival fibroblasts (HconF) were examined by the following analyses: (1) planar proliferation determined by transepithelial electrical resistance (TEER) and fluorescein isothiocyanate (FITC)-dextran permeability measurements, (2) real-time metabolic analyses, (3) measurements of the size and stiffness of 3D spheroids, and (4) mRNA expression of extracellular matrix (ECM) molecules and their modulators. RESULTS: LPA had no effect on TGF-ß2-induced increase in the planar proliferation of HconF cells. LPA induced a more quiescent metabolic state in 2D HconF cells, but this metabolic suppression by LPA was partially blunted in the presence of TGF-ß2. In contrast, LPA caused a substantial decrease in the hardness of 3D HconF spheroids independently of TGF-ß2. In agreement with these different LPA-induced effects between 2D and 3D cultured HconF cells, mRNA expressions of ECM and their modulators were differently modulated. CONCLUSION: The findings that LPA induced the inhibition of both TGF-ß2-related and -unrelated subepithelial proliferation of HconF cells may be clinically applicable.

The Specific ROCK2 Inhibitor KD025 Alleviates Glycolysis through Modulating STAT3-, CSTA- and S1PR3-Linked Signaling in Human Trabecular Meshwork Cells.

To investigate the biological significance of Rho-associated coiled-coil-containing protein kinase (ROCK) 2 in the human trabecular meshwork (HTM), changes in both metabolic phenotype and gene expression patterns against a specific ROCK2 inhibitor KD025 were assessed in planar-cultured HTM cells. A seahorse real-time ATP rate assay revealed that administration of KD025 significantly suppressed glycolytic ATP production rate and increased mitochondrial ATP production rate in HTM cells. RNA sequencing analysis revealed that 380 down-regulated and 602 up-regulated differentially expressed genes (DEGs) were identified in HTM cells treated with KD025 compared with those that were untreated. Gene ontology analysis revealed that DEGs were more frequently related to the plasma membrane, extracellular components and integral cellular components among cellular components, and related to signaling receptor binding and activity and protein heterodimerization activity among molecular functions. Ingenuity Pathway Analysis (IPA) revealed that the detected DEGs were associated with basic cellular biological and physiological properties, including cellular movement, development, growth, proliferation, signaling and interaction, all of which are associated with cellular metabolism. Furthermore, the upstream regulator analysis and causal network analysis estimated IL-6, STAT3, CSTA and S1PR3 as possible regulators. Current findings herein indicate that ROCK2 mediates the IL-6/STAT3-, CSTA- and S1PR3-linked signaling related to basic biological activities such as glycolysis in HTM cells.

TGF-ß Isoforms and Local Environments Greatly Modulate Biological Nature of Human Retinal Pigment Epithelium Cells.

To characterize transforming growth factor-ß (TGF-ß) isoform (TGF-ß1~3)-b's biological effects on the human retinal pigment epithelium (RPE) under normoxia and hypoxia conditions, ARPE19 cells cultured by 2D (two-dimensional) and 3D (three-dimensional) conditions were subjected to various analyses, including (1) an analysis of barrier function by trans-epithelial electrical resistance (TEER) measurements; (2) qPCR analysis of major ECM molecules including collagen 1 (COL1), COL4, and COL6; α-smooth muscle actin (αSMA); hypoxia-inducible factor 1α (HIF1α); and peroxisome proliferator-activated receptor-gamma coactivator (PGC1α), a master regulator for mitochondrial respiration;, tight junction-related molecules, Zonula occludens-1 (ZO1) and E-cadherin; and vascular endothelial growth factor (VEGF); (3) physical property measurements of 3D spheroids; and (4) cellular metabolic analysis. Diverse effects among TGF-ß isoforms were observed, and those effects were also different between normoxia and hypoxia conditions: (1) TGF-ß1 and TGF-ß3 caused a marked increase in TEER values, and TGF-ß2 caused a substantial increase in TEER values under normoxia conditions and hypoxia conditions, respectively; (2) the results of qPCR analysis supported data obtained by TEER; (3) 3D spheroid sizes were decreased by TGF-ß isoforms, among which TGF-ß1 had the most potent effect under both oxygen conditions; (4) 3D spheroid stiffness was increased by TGF-ß2 and TGF-ß3 or by TGF-ß1 and TGF-ß3 under normoxia conditions and hypoxia conditions, respectively; and (5) the TGF-ß isoform altered mitochondrial and glycolytic functions differently under oxygen conditions and/or culture conditions. These collective findings indicate that the TGF-ß-induced biological effects of 2D and 3D cultures of ARPE19 cells were substantially diverse depending on the three TGF-ß isoforms and oxygen levels, suggesting that pathological conditions including epithelial-mesenchymal transition (EMT) of the RPE may be exclusively modulated by both factors.

FABP4 Is an Indispensable Factor for Regulating Cellular Metabolic Functions of the Human Retinal Choroid.

The purpose of the current study was to elucidate the physiological roles of intraocularly present fatty acid-binding protein 4 (FABP4). Using four representative intraocular tissue-derived cell types, including human non-pigmented ciliary epithelium (HNPCE) cells, retinoblastoma (RB) cells, adult retinal pigment epithelial19 (ARPE19) cells and human ocular choroidal fibroblast (HOCF) cells, the intraocular origins of FABP4 were determined by qPCR analysis, and the intracellular functions of FABP4 were investigated by seahorse cellular metabolic measurements and RNA sequencing analysis using a specific inhibitor for FABP4, BMS309403. Among these four different cell types, FABP4 was exclusively expressed in HOCF cells. In HOCF cells, both mitochondrial and glycolytic functions were significantly decreased to trace levels by BMS309403 in a dose-dependent manner. In the RNA sequencing analysis, 67 substantially up-regulated and 94 significantly down-regulated differentially expressed genes (DEGs) were identified in HOCF cells treated with BMS309403 and those not treated with BMS309403. The results of Gene Ontology enrichment analysis and ingenuity pathway analysis (IPA) revealed that the DEGs were most likely involved in G-alpha (i) signaling, cAMP-response element-binding protein (CREB) signaling in neurons, the S100 family signaling pathway, visual phototransduction and adrenergic receptor signaling. Furthermore, upstream analysis using IPA suggested that NKX2-1 (thyroid transcription factor1), HOXA10 (homeobox A10), GATA2 (gata2 protein), and CCAAT enhancer-binding protein A (CEBPA) were upstream regulators and that NKX homeobox-1 (NKX2-1), SFRP1 (Secreted frizzled-related protein 1) and TREM2 (triggering receptor expressed on myeloid cells 2) were causal network master regulators. The findings in this study suggest that intraocularly present FABP4 originates from the ocular choroid and may be a critical regulator for the cellular homeostasis of non-adipocyte HOCF cells.

Tirzepatide ameliorates eating behaviors regardless of prior exposure to glucagon-like peptide receptor agonists in Japanese patients with type 2 diabetes mellitus.

AIMS: To investigate effects of tirzepatide, a dual receptor agonist for glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1 (GLP-1), on eating behaviors. METHODS: Eating behaviors were evaluated by using a validated questionnaire survey in 33 Japanese patients with type 2 diabetes mellitus (T2DM) (mean age: 51.8 years) who were treated with tirzepatide (2.5 mg/week for 4 weeks and then 5.0 mg/week) for 6 months (M). RESULTS: Treatment with tirzepatide significantly decreased median hemoglobin A1c (HbA1c) (baseline/3 M/6 M: 7.3 %/6.0 %/5.8 %), mean body weight (BW) (baseline/3 M/6 M: 87.7 kg/82.0 kg/79.6 kg) and mean relative score of eating behaviors (baseline/3 M/6 M: 57.0/50.7/45.9). In the GLP-1 receptor agonist (GLP-1RA) naïve group (n = 20, men/women: 13/7), HbA1c and BW were continuously decreased up to 6 M. Changes in eating behaviors were mainly observed in the first 3 M. In the GLP-1RA non-naïve group (n = 13, men/women: 8/5), reductions in HbA1c and BW were predominant in the first 3 M, and changes in eating behaviors were observed up to 6 M. There were no significant correlations of changes in scores of eating behaviors with changes in glycemic control or those in BW. CONCLUSIONS: Tirzepatide ameliorates eating behaviors as well as glycemic management and obesity in Japanese patients with T2DM, and the patterns of improvement are partially dependent on prior exposure to GLP-1RAs.

Modulation of Epithelial-Mesenchymal Transition Is a Possible Underlying Mechanism for Inducing Chemoresistance in MIA PaCa-2 Cells against Gemcitabine and Paclitaxel.

To elucidate the currently unknown molecular mechanisms responsible for the similarity and difference during the acquirement of resistance against gemcitabine (GEM) and paclitaxel (PTX) in patients with pancreatic carcinoma, we examined two-dimensional (2D) and three-dimensional (3D) cultures of parent MIA PaCa-2 cells (MIA PaCa-2-PA) and their GEM resistance cell line (MIA PaCa-2-GR) and PTX resistance (MIA PaCa-2-PR). Using these cells, we examined 3D spheroid configurations and cellular metabolism, including mitochondrial and glycolytic functions, with a Seahorse bio-analyzer and RNA sequencing analysis. Compared to the MIA PaCa-2-PA, (1) the formation of the 3D spheroids of MIA PaCa-2-GR or -PR was much slower, and (2) their mitochondrial and glycolytic functions were greatly modulated in MIA PaCa-2-GR or -PR, and such metabolic changes were also different between their 2D and 3D culture conditions. RNA sequencing and bioinformatic analyses of the differentially expressed genes (DEGs) using an ingenuity pathway analysis (IPA) suggested that various modulatory factors related to epithelial -mesenchymal transition (EMT) including STAT3, GLI1, ZNF367, NKX3-2, ZIC2, IFIT2, HEY1 and FBLX, may be the possible upstream regulators and/or causal network master regulators responsible for the acquirement of drug resistance in MIA PaCa-2-GR and -PR. In addition, among the prominently altered DEGs (Log2 fold changes more than 6 or less than -6), FABP5, IQSEC3, and GASK1B were identified as unique genes associated with their antisense RNA or pseudogenes, and among these, FABP5 and GASK1B are known to function as modulators of cancerous EMT. Therefore, the observations reported herein suggest that modulations of cancerous EMT may be key molecular mechanisms that are responsible for inducing chemoresistance against GEM or PTX in MIA PaCa-2 cells.

Adverse plasma branched-chain amino acid profile mirrors fatty muscle degeneration in diabetic heart failure patients.

AIMS: Elevated plasma branched-chain amino acids (BCAAs) are tightly linked to incident diabetes and its complications, while lower BCAAs are associated with adverse outcomes in the elderly and heart failure (HF) patients. The interplay between body compositions and plasma BCAAs, especially under the influence of co-morbid diabetes in HF patients, is not well understood. Here, we examined the impact of diabetes on the prognostic value of plasma BCAA and its association with body compositions in HF patients. METHODS AND RESULTS: We retrospectively examined 301 HF patients (70 ± 15 years old; 59% male), among which 36% had diabetes. Blood samples for plasma BCAA measurements were collected in a fasting state after stabilization of HF and analysed using ultraperformance liquid chromatography. A dual-energy X-ray absorptiometry scan assessed regional body compositions, and muscle wasting was defined as appendicular skeletal muscle mass index (ASMI) < 7.00 and <5.40 kg/m2 for males and females, respectively, according to the criteria of the Asian Working Group for Sarcopenia. Although analyses of covariance revealed that plasma BCAAs were significantly higher in diabetic patients, low valine (<222.1 nmol/mL) similarly predicted adverse events defined by HF hospitalization, lethal arrhythmia, or all-cause death in both diabetic and non-diabetic patients independently of age, sex, and NT-proBNP (adjusted hazard ratio [HR] 3.1, 95% confidence interval [CI] of 1.1-8.6 and adjusted HR 2.67, 95% CI 1.1-6.5, respectively; P for interaction 0.88). In multivariate linear regression analyses comprising age, sex, and regional body compositions as explanatory variables, plasma BCAAs were positively correlated with visceral adipose tissue area in non-diabetic patients (standardized ß coefficients [ß] = 0.44, P < 0.001). In contrast, in diabetic patients, plasma BCAAs were correlated positively with ASMI (ß = 0.49, P = 0.001) and negatively with appendicular fat mass index (AFMI; ß = -0.42, P = 0.004). Co-morbid diabetes was independently associated with muscle wasting (adjusted odds ratio 2.1, 95% CI 1.1-4.0) and significantly higher plasma 3-methylhistidine level, a marker of myofibrillar degradation. In diabetic patients, ASMI uniquely showed a J-shaped relationship with AFMI, and in a subgroup of HF patients with muscle wasting, diabetic patients showed 12% higher AFMI than non-diabetic patients despite comparable ASMI reductions. CONCLUSIONS: Despite higher plasma BCAA levels in HF patients with diabetes, the prognostic value of low valine remained consistent regardless of diabetes status. However, low BCAAs were distinctly associated with fatty muscle degeneration in the extremities in diabetic patients, suggesting the importance of targeted interventions to prevent such tissue remodelling in this population.

Associations between in-hospital daily protein intake and adverse clinical outcomes in older patients with heart failure.

AIMS: The adverse effects of low daily protein intake (DPI) on clinical outcomes in patients with heart failure (HF) are known; however, an optimal DPI to predict event adverse outcomes remains undetermined. Moreover, whether protein restriction therapy for chronic kidney disease is applicable in patients with HF and renal dysfunction remains unclear. METHODS AND RESULTS: In this single-centre, ambispective cohort study, we included 405 patients with HF aged ≥65 years (mean age, 78.6 ± 7.5 years; 50% women). DPI was estimated from consumption over three consecutive days before discharge and normalized relative to the ideal body weight [IBW, 22 kg/m2 × height (m)2]. The primary outcome was a composite of all-cause mortality and HF-related readmission within the 2 year post-discharge period. RESULTS: During an average follow-up period of 1.49 ± 0.74 years, 100 patients experienced composite events. Kaplan-Meier survival curves revealed a significantly lower composite event-free rate in patients within the lowest quartile of DPI than in the upper quartiles (log-rank test, P = 0.02). A multivariate Cox proportional hazards analysis after adjusting for established prognostic markers and non-proteogenic energy intake revealed that patients in the lowest DPI quartile faced a two-fold higher risk of composite events than those in the highest quartile [hazard ratio (HR), 2.03; 95% confidence interval (CI), 1.08-3.82; P = 0.03]. The composite event risk linearly increased as DPI decreased (P for nonlinearity = 0.90), with each standard deviation (0.26 g/kg IBW/day) decrease in DPI associated with a 32% increase in composite event risk (HR, 1.32; 95% CI, 1.10-1.71; P = 0.04). There was significant heterogeneity in the effect of DPI, with the possible disadvantage of lower DPI in patients with HF with cystatin C-based estimated glomerular filtration rate <30 mL/min/1.73 m2. The cutoff value of DPI for predicting the occurrence of composite events calculated from the Youden index was 1.12 g/kg IBW/day. Incorporating a DPI < 1.12 g/kg IBW/day into the baseline model significantly improved the prediction of post-discharge composite events (continuous net reclassification improvement, 0.294; 95% CI, 0.072-0.516; P = 0.01). CONCLUSIONS: Lower DPI during hospitalization is associated with an increased risk of mortality and HF readmission independent of non-proteogenic energy intake, and the possible optimal DPI for predicting adverse clinical outcomes is >1.12 g/kg IBW/day in older patients with HF. Caution is warranted when protein restriction therapy is administered to older patients with HF and renal dysfunction.

Deciphering metabolic dysfunction-associated steatotic liver disease: insights from predictive modeling and clustering analysis.

BACKGROUND AND AIM: New nomenclature of steatotic liver disease (SLD) including metabolic dysfunction-associated SLD (MASLD), MASLD and increased alcohol intake (MetALD), and alcohol-associated liver disease (ALD) has recently been proposed. We investigated clustering analyses to decipher the complex landscape of SLD pathologies including the former nomenclature of nonalcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD). METHODS: Japanese individuals who received annual health checkups including abdominal ultrasonography (n = 15 788, men/women: 10 250/5538, mean age: 49 years) were recruited. RESULTS: The numbers of individuals with SLD, MASLD, MetALD, ALD, NAFLD, and MAFLD were 5603 (35.5%), 4227 (26.8%), 795 (5.0%), 324 (2.1%), 3982 (25.8%), and 4946 (31.3%), respectively. Clustering analyses using t-distributed stochastic neighbor embedding and K-means to visually represent interconnections in SLDs uncovered five cluster formations. MASLD and NAFLD mainly shared three clusters including (i) low alcohol intake with relatively low-grade obesity; (ii) obesity with dyslipidemia; and (iii) dysfunction of glucose metabolism. Both MetALD and ALD displayed one distinct cluster intertwined with alcohol consumption. MAFLD widely shared all of the five clusters. In machine learning-based analyses using algorithms of random forest and extreme gradient boosting and receiver operating characteristic curve analyses, fatty liver index (FLI), calculated by body mass index, waist circumference, and levels of γ-glutamyl transferase and triglycerides, was selected as a useful feature for SLDs. CONCLUSIONS: The new nomenclature of SLDs is useful for obtaining a better understanding of liver pathologies and for providing valuable insights into predictive factors and the dynamic interplay of diseases. FLI may be a noninvasive predictive marker for detection of SLDs.

Downregulation of Mitochondrial Fusion Protein Expression Affords Protection from Canonical Necroptosis in H9c2 Cardiomyoblasts.

Necroptosis, a form of necrosis, and alterations in mitochondrial dynamics, a coordinated process of mitochondrial fission and fusion, have been implicated in the pathogenesis of cardiovascular diseases. This study aimed to determine the role of mitochondrial morphology in canonical necroptosis induced by a combination of TNFα and zVAD (TNF/zVAD) in H9c2 cells, rat cardiomyoblasts. Time-course analyses of mitochondrial morphology showed that mitochondria were initially shortened after the addition of TNF/zVAD and then their length was restored, and the proportion of cells with elongated mitochondria at 12 h was larger in TNF/zVAD-treated cells than in non-treated cells (16.3 ± 0.9% vs. 8.0 ± 1.2%). The knockdown of dynamin-related protein 1 (Drp1) and fission 1, fission promoters, and treatment with Mdivi-1, a Drp-1 inhibitor, had no effect on TNF/zVAD-induced necroptosis. In contrast, TNF/zVAD-induced necroptosis was attenuated by the knockdown of mitofusin 1/2 (Mfn1/2) and optic atrophy-1 (Opa1), proteins that are indispensable for mitochondrial fusion, and the attenuation of necroptosis was not canceled by treatment with Mdivi-1. The expression of TGFß-activated kinase (TAK1), a negative regulator of RIP1 activity, was upregulated and the TNF/zVAD-induced RIP1-Ser166 phosphorylation, an index of RIP1 activity, was mitigated by the knockdown of Mfn1/2 or Opa1. Pharmacological TAK1 inhibition attenuated the protection afforded by Mfn1/2 and Opa1 knockdown. In conclusion, the inhibition of mitochondrial fusion increases TAK1 expression, leading to the attenuation of canonical necroptosis through the suppression of RIP1 activity.

Differential Effects of Benzalkonium Chloride on Human Trabecular Meshwork Cells Not Treated or Treated with Transforming Growth Factor-ß2 or Dexamethasone.

Purpose: The objective of the present study was to evaluate the effects of low concentrations of benzalkonium chloride (BAC) (10-7%, 10-6%, or 10-5%) on healthy and glaucomatous human trabecular meshwork (HTM) cells. For this purpose, we used in vitro models replicating a healthy HTM and HTM with primary open-angle glaucoma (POAG) or steroid-induced glaucoma (SG) using two-dimensional (2D) cultures of HTM cells not treated or treated with a 5 ng/mL solution of transforming growth factor-ß2 or 250 nM dexamethasone (DEX). Methods: Analyses were carried out for (1) the intercellular affinity function of 2D HTM monolayers, as determined by transepithelial electrical resistance (TEER) measurements; (2) cell viability; (3) cellular metabolism by using a Seahorse bioanalyzer; and (4) expression of extracellular matrix (ECM) molecules, an ECM modulator, and cell junction-related molecules. Results: In the absence and presence of BAC (10-7% or 10-5%), intercellular affinity function determined by TEER and cellular metabolic activities were significantly and dose dependently affected in both healthy and glaucomatous HTM cells despite the fact that there was no significant decrease in cell viabilities. However, the effects based on TEER values were significantly greater in the healthy HTM. The mRNA expression of several molecules that were tested was not substantially modulated by these concentrations of BAC. Conclusions: The findings reported herein suggest that low concentrations of BAC may have unfavorable adverse effects on cellular metabolic capacity by inducing increases in the intercellular affinity properties of the HTM, but those effects of BAC were different in healthy and glaucomatous HTM cells.

Validation of Estimated Small Dense Low-Density Lipoprotein Cholesterol Concentration in a Japanese General Population.

AIM: A high level of directly measured small dense low-density lipoprotein cholesterol (sdLDL-C) is a strong risk factor for atherosclerotic cardiovascular disease. A method for estimating sdLDL-C by using Sampson's equation that includes levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C), non-HDL-C and triglycerides (TG) has recently been proposed. We investigated the validation and exploration of estimated sdLDL-C level. METHODS: The associations between measured and estimated sdLDL-C levels were investigated in 605 Japanese subjects (men/women: 280/325; mean age: 65±15 years) who received annual health check-ups in the Tanno-Sobetsu Study, a population-based cohort. RESULTS: Estimated sdLDL-C level was highly correlated with measured sdLDL-C level in all subjects (R2=0.701), nondiabetic subjects without any medication (n=254, R2=0.686) and subjects with diabetes mellitus (n=128, R2=0.721). Multivariable regression analysis showed that levels of non-HDL-C, TG and γ-glutamyl transpeptidase (γGTP) were independent predictors of measured sdLDL-C level. In a stratification of the LDL window, all of the subjects with a combination of high non-HDL-C (≥ 170 mg/dL) and high TG (≥ 150 mg/dL) had high levels of measured and estimated sdLDL-C (≥ 35 mg/dL). Furthermore, machine learning-based estimation of sdLDL-C level by artificial intelligence software, Prediction One, was substantially improved by using components of Sampson's equation (R2=0.803) and by using those components with the addition of γGTP and deletion of TC (R2=0.929). CONCLUSIONS: sdLDL-C level estimated by Sampson's equation can be used instead of measured sdLDL-C level in general practice. By building multiple machine learning models of artificial intelligence, a more accurate and practical estimation of sdLDL-C level might be possible.

Significant and Various Effects of ML329-Induced MITF Suppression in the Melanoma Cell Line.

To study the inhibitory effects on microphthalmia-associated transcription factor (MITF)-related biological aspects in malignant melanomas (MMs) in the presence or absence of the low-molecular MITF specific inhibitor ML329, cell viability, cellular metabolic functions, and three-dimensional (3D) spheroid formation efficacy were compared among MM cell lines including SK-mel-24, A375, dabrafenib- and trametinib-resistant A375 (A375DT), and WM266-4. Upon exposure to 2 or 10 µM of ML329, cell viability was significantly decreased in WM266-4, SK-mel-24, and A375DT cells, but not A375 cells, in a dose-dependent manner, and these toxic effects of ML329 were most evident in WM266-4 cells. Extracellular flux assays conducted using a Seahorse bioanalyzer revealed that treatment with ML329 increased basal respiration, ATP-linked respiration, proton leakage, and non-mitochondrial respiration in WM266-4 cells and decreased glycolytic function in SK-mel-24 cells, whereas there were no marked effects of ML329 on A375 and A375DT cells. A glycolytic stress assay under conditions of high glucose concentrations also demonstrated that the inhibitory effect of ML329 on the glycolytic function of WM266-4 cells was dose-dependent. In addition, ML329 significantly decreased 3D-spheroid-forming ability, though the effects of ML329 were variable among the MM cell lines. Furthermore, the mRNA expression levels of selected genes, including STAT3 as a possible regulator of 3D spheroid formation, KRAS and SOX2 as oncogenic-signaling-related factors, PCG1a as the main regulator of mitochondrial biogenesis, and HIF1a as a major hypoxia transcriptional regulator, fluctuated among the MM cell lines, possibly supporting the diverse ML329 effects mentioned above. The findings of diverse ML329 effects on various MM cell lines suggest that MITF-associated biological activities are different among various types of MM.

Calculated Small Dense Low-Density Lipoprotein Cholesterol Level is A Predominant Predictor for New Onset of Ischemic Heart Disease.

AIM: A high level of directly measured small dense low-density lipoprotein cholesterol (sdLDL-C) is a strong risk factor for ischemic heart disease (IHD). However, it remains unclear whether estimated sdLDL-C level is a predictor for IHD. We investigated the associations of new onset of IHD with levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), non-HDL-C, triglycerides (TG), LDL-C and calculated sdLDL-C by Sampson's equation. METHODS: After exclusion of subjects with IHD or those with TG ≥ 800 mg/dL, a total of 18,176 subjects (men/women: 11,712/6,464, mean age: 46 years) were recruited among 28,990 Japanese individuals who received annual health checkups. RESULTS: During the 10-year follow-up period, 456 men (3.9%) and 121 women (1.9%) newly developed IHD. Multivariable Cox proportional hazard analyses after adjustment of age, sex, obesity, smoking habit, family history of IHD, estimated glomerular filtration rate, hypertension and diabetes mellitus at baseline showed that the hazard ratio (HR) (1.38 [95% confidence interval: 1.03-1.85]) for new onset of IHD in subjects with the 4th quartile (Q4) of sdLDL-C (≥ 42 mg/dL) was significantly higher than that in subjects with the 1st quartile (Q1) (≤ 24 mg/dL) as the reference, though the adjusted HRs in subjects with Q2-Q4 of TC, HDL-C, non-HDL-C, LDL-C and TG were comparable with those in subjects with Q1 of the respective lipid fractions. The adjusted HR with a restricted cubic spline increased with a higher level of calculated sdLDL-C as a continuous value at baseline. CONCLUSIONS: sdLDL-C level calculated by Sampson's equation is a predominant predictor for the development of IHD in a general Japanese population.

Relationship between serum iron level and physical function in heart failure patients is lost by presence of diabetes.

AIMS: Iron deficiency (ID) is common in patients with heart failure (HF) and is reportedly associated with exercise intolerance and impaired quality of life. Iron supplementation therapy in HF patients with ID improves exercise capacity. Conversely, protective roles of iron depletion in the development of diabetes mellitus (DM) and its complications have been proposed. This study aimed to determine the impact of ID on physical function in HF patients with and without DM. METHODS AND RESULTS: We enrolled consecutive patients who were admitted to our institute for HF diagnosis and management. The short physical performance battery (SPPB) was used to evaluate physical function, and low physical function was defined as an SPPB score of <10 points as individuals with SPPB scores of <10 points are most likely to be classified as frail and are at high risk for disability and future adverse events, including death. ID was defined as serum ferritin < 100 or 100-299 ng/mL when transferrin saturation (TSAT) was <20% according to the HF guidelines. Among the 562 HF patients (72 ± 14 years old; 56% male), 329 patients (58%) and 191 patients (34%) had ID and low physical function, respectively. Multivariate logistic regression analysis showed that TSAT as a continuous variable, but not ID, was a predictor of low physical function (odds ratio: 0.980, P = 0.024). Subgroup analysis showed that a significant association between low TSAT and low physical function was lost in HF patients with DM (P for interaction < 0.001). A spline dose-response curve for the relationship between TSAT and risk of low physical function with adjustments for covariates associated with low physical function in non-DM patients was almost linear with an increase in the risk of low physical function as the TSAT increased, but such a relationship was not found in the analyses of DM patients. A lack of close TSAT-SPPB relationship in HF patients with DM was confirmed also in a propensity-score-matched cohort. CONCLUSIONS: TSAT as a continuous variable, but not ID, was independently associated with physical function in HF patients, and a significant association was lost in patients with HF and DM, suggesting a limited impact of iron supplementation therapy in HF patients with DM.