Gram-negative anaerobes elicit a robust keratinocytes immune response with potential insights into HS pathogenesis.

Hidradenitis Suppurativa (HS) is a chronic autoinflammatory skin disease with activated keratinocytes, tunnel formation and a complex immune infiltrate in tissue. The HS microbiome is polymicrobial with an abundance of commensal gram-positive facultative (GPs) Staphylococcus species and gram-negative anaerobic (GNA) bacteria like Prevotella, Fusobacterium and Porphyromonas with increasing predominance of GNAs with disease severity. We sought to define the keratinocyte response to bacteria commonly isolated from HS lesions to probe pathogenic relationships between HS and the microbiome. Type strains of Prevotella nigrescens, Prevotella melaninogenica, Prevotella intermedia, Prevotella asaccharolytica, Fusobacterium nucleatum, as well as Staphylococcus aureus and the normal skin commensal Staphylococcus epidermidis were heat-killed and co-incubated with normal human keratinocytes. RNA was collected and analysed using RNAseq and RT-qPCR. The supernatant was collected from cell culture for protein quantification. Transcriptomic profiles between HS clinical samples and stimulated keratinocytes were compared. Co-staining of patient HS frozen sections was used to localize bacteria in lesions. A mouse intradermal injection model was used to investigate early immune recruitment. TLR4 and JAK inhibitors were used to investigate mechanistic avenues of bacterial response inhibition. GNAs, especially F. nucleatum, stimulated vastly higher CXCL8, IL17C, CCL20, IL6, TNF and IL36γ transcription in normal skin keratinocytes than the GPs S. epidermidis and S. aureus. Using RNAseq, we found that F. nucleatum (and Prevotella) strongly induced the IL-17 pathway in keratinocytes and overlapped with transcriptome profiles of HS patient clinical samples. Bacteria were juxtaposed to activated keratinocytes in vivo, and F. nucleatum strongly recruited murine neutrophil and macrophage migration. Both the TLR4 and pan-JAK inhibitors reduced cytokine production. Detailed transcriptomic profiling of healthy skin keratinocytes exposed to GNAs prevalent in HS revealed a potent, extensive inflammatory response vastly stronger than GPs. GNAs stimulated HS-relevant genes, including many genes in the IL-17 response pathway, and were significantly associated with HS tissue transcriptomes. The close association of activated keratinocytes with bacteria in HS lesions and innate infiltration in murine skin cemented GNA pathogenic potential. These novel mechanistic insights could drive future targeted therapies.

Predictors of rituximab effect on modified Rodnan skin score in systemic sclerosis: a machine-learning analysis of the DesiReS trial.

OBJECTIVES: The double-blind, parallel-group comparison, investigators initiated phase II clinical trial of IDEC-C2B8 (Rituximab) in patients with Systemic sclerosis (DesiReS) trial showed that rituximab is effective in treating skin sclerosis in SSc. However, which patient groups are likely to benefit from rituximab is unknown. METHODS: We performed post-hoc analysis of prospective data from 54 patients who received rituximab or placebo in the DesiReS trial. Twenty-seven baseline factors were used to investigate subpopulations with different magnitudes of rituximab effect on modified Rodnan skin score (mRSS) change at 24 weeks. Based on a machine-learning algorithm called the causal tree, we explored the combination of predictors needed to identify subpopulations that would respond to rituximab and have good treatment outcomes. RESULTS: Three factors were identified as branches of the decision tree: peripheral blood CD19-positive cell counts', 'mRSS', and 'serum surfactant protein D (SP-D) levels'. It was only in the subpopulation of patients with CD19-positive cell counts of <57/µl that rituximab did not show a significant improvement in mRSS vs placebo. In the subpopulation of patients with CD19-positive cell counts of ≥57/µl and mRSS ≥ 17, mRSS was most improved with rituximab [difference -17.06 (95% CI: -24.22, -9.89)]. The second greatest improvement in mRSS with rituximab was in the subpopulation with CD19-positive cell counts of ≥57/µl, mRSS < 17, and serum SP-D levels of ≥151 ng/ml [difference -10.35 (95% CI: -14.77, -5.93)]. CONCLUSION: SSc patients who have high CD19-positive cell counts and high mRSS are expected to have greater improvement in mRSS with rituximab. When the patients with high CD19-positive cell counts show low mRSS, serum SP-D levels may modify the treatment effect. TRIAL REGISTRATION: ClinicalTrials.gov, https://clinicaltrials.gov, NCT04274257 and UMIN-CTR; https://center6.umin.ac.jp, UMIN000030139.

Fli1 deficiency induces endothelial adipsin expression, contributing to the onset of pulmonary arterial hypertension in systemic sclerosis.

OBJECTIVES: Adipsin, or complement factor D, is a serine proteinase catalysing complement factor C3 breakdown, leading to the production of opsonin (C3b), membrane attack complex (C5b-C9) and anaphylatoxins (C3a and C5a). Since adipsin is potentially associated with pulmonary arterial hypertension in SSc, we investigated adipsin expression in dermal small vessels of SSc-involved skin, the mechanism regulating adipsin expression in endothelial cells, and the correlation of serum adipsin levels with SSc clinical symptoms. METHODS: Adipsin expression was assessed by immunohistochemistry with skin sections of SSc and healthy subjects. mRNA levels of target genes and transcription factor binding to the ADIPSIN promoter were evaluated by quantitative reverse transcription PCR and chromatin immunoprecipitation, respectively. Serum adipsin levels were determined by enzyme-linked immunosorbent assay. RESULTS: Adipsin expression was remarkably increased in dermal small vessels of SSc-involved skin as compared with those of healthy control skin. Consistent with the notion that Fli1 deficiency induces SSc-like phenotypes in various types of cells, FLI1 siRNA enhanced adipsin expression at protein and mRNA levels and Fli1 bound to the ADIPSIN promoter in human dermal microvascular endothelial cells. Serum adipsin levels were significantly lower in diffuse cutaneous SSc patients than in limited cutaneous SSc patients and healthy controls, and were associated positively with elevated right ventricular systolic pressure and inversely with interstitial lung disease by multivariate regression analysis. CONCLUSION: Adipsin is up-regulated at least partially by Fli1 deficiency in endothelial cells, potentially contributing to the development of pulmonary vascular involvement in SSc.

A potential contribution of decreased galectin-7 expression in stratified epithelia to the development of cutaneous and oesophageal manifestations in systemic sclerosis.

BACKGROUNDS: Stratified epithelia have caught much attention as potential contributors to the development of dermal and oesophageal fibrosis in systemic sclerosis (SSc). Galectin-7 is a marker of all types of stratified epithelia, which is involved in the maintenance of epidermal homeostasis. So far, the role of galectin-7 has not been studied in SSc. OBJECTIVES: To investigate the potential contribution of galectin-7 to the development of clinical manifestations in SSc. METHODS: Galectin-7 expression was examined in skin samples and cultured keratinocytes by immunostaining and/or quantitative reverse transcription PCR. Serum galectin-7 levels were determined by enzyme-linked immunosorbent assay in 63 SSc and 20 healthy subjects. RESULTS: Galectin-7 expression was markedly decreased in the epidermis of SSc lesional skin compared with that of healthy control skin. Serum galectin-7 levels were significantly lower in SSc patients than in healthy controls and inversely correlated with skin score. In addition, SSc patients with diffuse pigmentation and those with oesophageal dysfunction had significantly decreased serum galectin-7 levels as compared to those without each symptom. Importantly, endothelin-1 stimulation suppressed galectin-7 expression in normal human keratinocytes, and bosentan, a dual endothelin receptor antagonist, reversed circulating galectin-7 levels and epidermal galectin-7 expression in SSc patients. CONCLUSIONS: Galectin-7 downregulation in stratified epithelia, which is mediated at least partially by autocrine endothelin stimulation, may contribute to the development of cutaneous manifestations and oesophageal dysfunction in SSc patients.

Telomerase Plays a Pivotal Role in Collateral Growth Under Ischemia by Suppressing Age-Induced Oxidative Stress, Expression of p53, and Pro-Apoptotic Proteins.

Aging is not only a major risk factor for impaired collateral growth under ischemia but also shortens the telomere length, which is regulated by telomerase. We examined the role of telomerase activity during impaired collateral growth during aging in ischemic skeletal muscle. Unilateral hind limb ischemia was generated in old, young, and old mice chronically administered a telomerase activator. In old mice, blood flow recovery and capillary density development in ischemic hind limbs were reduced compared to those in young mice, and these changes were restored to equal levels by administration of TA-65, a telomerase activator. During the early phase of ischemic muscle changes in old mice, telomerase reverse transcriptase expression and telomerase activity were both low compared to those in young mice and old mice treated with TA-65. Levels of reactive oxygen species (ROS), DNA double-strand breaks, and expression of p53, p16, and Bax/Bcl-2 were all elevated in ischemic muscles of old mice compared to those in the muscles of young mice and old mice treated with TA-65 treatment; these factors were maintained at low levels equivalent to those seen in young mice during the experiment. Expression of HIF1α/vascular endothelial growth factor (VEGF) and PGC1α were decreased in old mice compared to those in young mice and old mice treated with TA-65. Collateral growth under ischemic conditions is impaired in aged animals due to low telomerase activity, increased ROS, resultant DNA damage, and expression of tumor suppressor and pro-apoptotic proteins. These data suggest that telomerase activation enhances collateral growth and rescues ischemic tissue in old individuals.

The impact of transcription factor Fli1 deficiency on the regulation of angiogenesis.

The insufficiency of Friend leukaemia virus integration 1 (Fli1), a member of the Ets family transcription factors, is implicated in the pathogenesis of vasculopathy associated with systemic sclerosis (SSc). Fli1 deficiency accelerates early steps of angiogenesis, including detachment of pre-existing pericytes and extracellular matrix degradation by endothelial proteinases, but the impact of Fli1 deficiency on the other steps of angiogenesis has not been investigated. Therefore, we evaluated the effect of Fli1 deficiency on migration, proliferation, cell survival and tube formation of human dermal microvascular endothelial cells (HDMECs). HDMECs transfected with FLI1 siRNA exhibited a greater migratory property in scratch assay and transwell migration assay and a higher proliferation rate in BrdU assay than HDMECs transfected with non-silencing scrambled RNA. In flow cytometry-based apoptosis assay, FLI1 siRNA-transduced HDMECs revealed the decreased number of annexin and propidium iodide-double-positive apoptotic cells compared with control cells, reflecting the promotion of cell survival. On the other hand, tubulogenic activity on Matrigel was remarkably suppressed in Fli1-deficient HDMECs relative to control cells. These results indicate that Fli1 deficiency promotes migration, proliferation and cell survival, while abating tube formation of endothelial cells, suggesting that Fli1 deficiency is potentially attributable to the development of both proliferative obliterative vasculopathy (occlusion of arterioles and small arteries) and destructive vasculopathy (loss of small vessels) characteristic of SSc vasculopathy.

Mitochondrial-Targeted Antioxidant Maintains Blood Flow, Mitochondrial Function, and Redox Balance in Old Mice Following Prolonged Limb Ischemia.

Aging is a major factor in the decline of limb blood flow with ischemia. However, the underlying mechanism remains unclear. We investigated the role of mitochondrial reactive oxygen species (ROS) with regard to limb perfusion recovery in aging during ischemia. We performed femoral artery ligation in young and old mice with or without treatment with a scavenger of mitochondrial superoxide, MitoTEMPO (180 µg/kg/day, from pre-operative day 7 to post-operative day (POD) 21) infusion using an implanted mini-pump. The recoveries of cutaneous blood flow in the ischemic hind limb were lower in old mice than in young mice but were improved in MitoTEMPO-treated old mice. Mitochondrial DNA damage appeared in ischemic aged muscles but was eliminated by MitoTEMPO treatment. For POD 2, MitoTEMPO treatment suppressed the expression of p53 and the ratio of Bax/Bcl2 and upregulated the expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in ischemic aged skeletal muscles. For POD 21, MitoTEMPO treatment preserved the expression of PGC-1α in ischemic aged skeletal muscle. The ischemic soleus of old mice showed a lower mitochondrial respiratory control ratio in POD 21 compared to young mice, which was recovered in MitoTEMPO-treated old mice. Scavenging of mitochondrial superoxide attenuated mitochondrial DNA damage and preserved the mitochondrial respiration, in addition to suppression of the expression of p53 and preservation of the expression of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) in ischemic skeletal muscles with aging. Resolution of excessive mitochondrial superoxide could be an effective therapy to recover blood flow of skeletal muscle during ischemia in senescence.

Associations With Eicosapentaenoic Acid to Arachidonic Acid Ratio and Mortality in Hospitalized Heart Failure Patients.

BACKGROUND: Intake of n-3 polyunsaturated fatty acids (n-3 PUFAs) lowers the risk of atherosclerotic cardiovascular events, particularly ischemic heart disease. In addition, the ratio of eicosapentaenoic acid (EPA; n-3 PUFA) to arachidonic acid (AA; n-6 PUFA) has recently been recognized as a risk marker of cardiovascular disease. In contrast, the prognostic impact of the EPA/AA ratio on patients with heart failure (HF) remains unclear. METHODS AND RESULTS: A total of 577 consecutive patients admitted for HF were divided into 2 groups based on median of the EPA/AA ratio: low EPA/AA (EPA/AA <0.32 mg/dl, n = 291) and high EPA/AA (EPA/AA ≥0.32, n = 286) groups. We compared laboratory data and echocardiographic findings and followed cardiac mortality. Although body mass index, blood pressure, B-type natriuretic peptide, hemoglobin, estimated glomerular filtration rate, total protein, albumin, sodium, C-reactive protein, and left ventricular ejection fraction did not differ between the 2 groups, cardiac mortality was significantly higher in the low EPA/AA group than in the high EPA/AA group (12.7 vs 5.9%, log-rank P = .004). Multivariate Cox proportional hazard analysis revealed that the EPA/AA ratio was an independent predictor of cardiac mortality (hazard ratio 0.677, 95% confidence interval 0.453-0.983, P = .041) in patients with HF. CONCLUSION: The EPA/AA ratio was an independent predictor of cardiac mortality in patients with HF; therefore, the prognosis of patients with HF may be improved by taking appropriate management to control the EPA/AA balance.

Prognostic Significance of Insomnia in Heart Failure.

BACKGROUND: Insomnia is associated with incident heart failure (HF), but the clinical significance and impact of insomnia on HF remain unclear. METHODS AND RESULTS: Consecutive 1,011 patients admitted for HF were divided into 2 groups according to the presence of insomnia: HF with insomnia (insomnia group, n=519) and HF without insomnia (non-insomnia group, n=492). We compared (1) cardiac event rates including cardiac death and worsening HF; and (2) underlying clinical background including laboratory data, echocardiographic data, and cardiopulmonary exercise test between the 2 groups. On Kaplan-Meier analysis, cardiac event rate was significantly higher in the insomnia group than in the non-insomnia group (39.1 vs. 23.4%, P<0.001). The insomnia group, as compared with the non-insomnia group, had (1) higher plasma renin activity (P=0.042), renin concentration (P=0.007), and aldosterone (P=0.047); (2) lower peak V̇O2(14.9 vs. 16.3 ml/kg/min, P=0.002) and higher V̇E/V̇CO2slope (36.0 vs. 33.5, P=0.001); and (3) similar B-type natriuretic peptide and left ventricular ejection fraction. Importantly, on multivariate Cox proportional hazard analysis after adjusting for potential confounding factors, insomnia was an independent predictor of cardiac events in HF patients (hazard ratio, 1.899; P<0.001). CONCLUSIONS: Insomnia is an independent predictor of cardiac events in HF patients. HF patients with insomnia have activated renin-angiotensin-aldosterone system and lower exercise capacity. (Circ J 2016; 80: 1571-1577).

Novel and recurrent ATP2A2 mutations in Japanese patients with Darier's disease.

Darier's disease (DD, keratosis follicularis: OMIM#124200) is an autosomal dominant skin disorder characterized by multiple dark brown keratotic plaques and warty papules covered by thick crusts. Most cases of DD are caused by mutations in ATP2A2, which is expressed in both the skin and the brain. ATP2A2 encodes the cardiac muscle SERCA2a protein and the ubiquitously expressed SERCA2b. SERCA2 plays an important role as a calcium pump. It is thought that a mutation in ATP2A2 causes dyskeratosis and abnormality of cell-cell adhesion. Here, we report five DD patients from five independent families who presented or were referred to the Nagoya University Hospital in the past five years. We detected five mutations in ATP2A2, including a previously unreported mutation. We observed no apparent genotype/phenotype correlation between types and sites of the ATP2A2 mutations and DD phenotypes in the present series of DD patients. Genetic diagnosis from ATP2A2 mutation search is useful for the definite diagnosis of DD, although it is difficult to predict the severity and prognosis of skin symptoms from the results of the ATP2A2 mutation analysis in DD patients.

Relationship of hyperuricemia with mortality in heart failure patients with preserved ejection fraction.

Serum uric acid is a predictor of cardiovascular mortality in heart failure with reduced ejection fraction. However, the impact of uric acid on heart failure with preserved ejection fraction (HFpEF) remains unclear. Here, we investigated the association between hyperuricemia and mortality in HFpEF patients. Consecutive 424 patients, who were admitted to our hospital for decompensated heart failure and diagnosed as having HFpEF, were divided into two groups based on presence of hyperuricemia (serum uric acid ≥7 mg/dl or taking antihyperuricemic agents). We compared patient characteristics, echocardiographic data, cardio-ankle vascular index, and cardiopulmonary exercise test findings between the two groups and prospectively followed cardiac and all-cause mortality. Compared with the non-hyperuricemia group (n = 170), the hyperuricemia group (n = 254) had a higher prevalence of hypertension (P = 0.013), diabetes mellitus (P = 0.01), dyslipidemia (P = 0.038), atrial fibrillation (P = 0.001), and use of diuretics (P < 0.001). Cardio-ankle vascular index (8.7 vs. 7.5, P < 0.001) and V̇e/V̇co2 slope (34.9 vs. 31.9, P = 0.02) were also higher. In addition, peak V̇o2 (14.9 vs. 17.9 ml·kg(-1)·min(-1), P < 0.001) was lower. In the follow-up period (mean 897 days), cardiac and all-cause mortalities were significantly higher in those with hyperuricemia (P = 0.006 and P = 0.004, respectively). In the multivariable Cox proportional hazard analyses after adjustment for several confounding factors including chronic kidney disease and use of diuretics, hyperuricemia was an independent predictor of all-cause mortality (hazard ratio 1.98, 95% confidence interval 1.036-3.793, P = 0.039). Hyperuricemia is associated with arterial stiffness, impaired exercise capacity, and high mortality in HFpEF.

Association of Hypocalcemia With Mortality in Hospitalized Patients With Heart Failure and Chronic Kidney Disease.

BACKGROUND: Chronic kidney disease--mineral and bone disorders (CKD-MBD) are associated with vascular calcification and abnormal electrolytes that lead to cardiovascular disease and mortality. CKD-MBD is identified by imbalances in serum calcium (Ca), phosphate, and parathyroid hormone (PTH). Although the relation of phosphate and PTH with the prognosis of HF patients has been reported, the association of Ca with prognosis in patients with heart failure (HF) and CKD remains unclear. METHODS AND RESULTS: We examined 191 patients admitted for HF and CKD (estimated glomerular filtration rate <60 mL min(-1) 1.73 m(-2)), and they were divided into 2 groups based on levels of corrected Ca: low Ca (Ca <8.4 mg/dL; n = 32) and normal-high Ca (8.4 ≤Ca; n = 159). We compared laboratory and echocardiographic findings, as well as followed cardiac and all-cause mortality. The low-Ca group had 1) higher levels of alkaline phosphatase (308.9 vs. 261.0 U/L; P = .026), 2) lower levels of 1,25-dihydroxy vitamin D (26.1 vs. 45.0 pg/mL; P = .011) and hydrogen carbonate (22.4 vs. 24.5 mmol/L; P = .031), and 3) a tendency to have a higher PTH level (87.5 vs. 58.6 pg/mL; P = .084). In contrast, left and right ventricular systolic function, estimated glomerular filtration rate, urine protein, phosphate, sodium, potassium, magnesium, and zinc did not differ between the 2 groups. In the Kaplan-Meier analysis, cardiac and all-cause mortality were significantly higher in the low-Ca group than in the normal-high-Ca group (P < .05). In the multivariable Cox proportional hazard analyses, hypocalcemia was an independent predictor of all-cause mortality in HF and CKD patients (P < .05). CONCLUSIONS: Hypocalcemia was an independent predictor of all-cause mortality in HF and CKD patients.

Impact of body mass index on mortality in heart failure patients.

BACKGROUND: Higher body mass index (BMI) is associated with incident heart failure (HF), but paradoxically associated with better prognosis, recognized as the obesity paradox in HF. However, the impact of BMI on detailed prognosis on HF and the mechanism of obesity paradox remain still unclear. MATERIALS AND METHODS: We researched consecutive 648 patients admitted for HF as follows: underweight (BMI < 18·5 kg/m(2) , n = 86), normal (18·5 ≤ BMI < 25, n = 380), overweight (25 ≤ BMI < 30, n = 147) and obese (30 ≤ BMI, n = 35) and compared the results from their laboratory tests and echocardiography. We also followed cardiac and all-cause mortality. RESULTS: Obese group had a higher prevalence of obesity-related comorbidity (hypertension, diabetes, dyslipidemia); however, tumour necrosis factor-α, adiponectin, troponin T and systolic pulmonary arterial pressure were higher in the underweight group than in the other groups (P < 0·05, respectively). Left and right ventricular systolic function did not differ among the groups. In the Kaplan-Meier analysis, cardiac and all-cause mortality progressively increased from obese to overweight, normal and underweight group. Importantly, in the Cox proportional hazard analyses after adjusting for known risk factors, BMI was an independent predictor of cardiac and all-cause mortality (P < 0·01, respectively) in HF patients. CONCLUSIONS: Body mass index was an independent predictor of cardiac death and all-cause mortality in HF patients. Furthermore, lower BMI was associated with higher circulating levels of tumour necrosis factor-α, adiponectin and troponin T and higher systolic pulmonary arterial pressure.

Hepatocyte Growth Factor has Unique Functions in Keratinocytes that differs from IL-17A and TNF and may contribute to Inflammatory Pathways in Hidradenitis Suppurativa.

Hidradenitis suppurativa (HS) is a chronic inflammatory disease that is difficult to control, and its mechanism remains unclear. Hepatocyte growth factor (HGF) has been reported to be significantly upregulated in the serum and skin of HS patients, especially in the lesions with tunnels. In this study, we examined the transcriptome of HGF-treated keratinocytes (KCs) and compared it with genetic profiling of HS lesions. HGF was highly expressed in HS skin, especially in the deep dermis, compared to healthy controls, and its source was mainly fibroblasts. HGF upregulated more genes in KCs than interleukin-17A or tumor necrosis factor-α, and these genes included multiple epithelial-mesenchymal transition (EMT)-related genes. Differentially expressed genes in HGF-stimulated KCs were involved in activation of EMT-related pathways. These HGF-induced genes were significantly upregulated in HS lesions compared to healthy skin and non-lesions and were more strongly associated with HS tunnels. In summary, HGF was highly expressed in HS and induced EMT-related genes in KCs; HGF-induced genes were highly associated with gene profiling of HS with tunnels, suggesting that HGF may be involved in HS tunnel formation via EMT.

Neutrophil Extracellular Traps in Myocardial Tissue Drive Cardiac Dysfunction and Adverse Outcomes in Patients With Heart Failure With Dilated Cardiomyopathy.

BACKGROUND: The immune systems and chronic inflammation are implicated in the pathogenesis of dilated cardiomyopathy (DCM) and heart failure. However, the significance of neutrophil extracellular traps (NETs) in heart failure remains to be elucidated. METHODS: We enrolled consecutive 62 patients with heart failure with idiopathic DCM who underwent endomyocardial biopsy. Biopsy specimens were subjected to fluorescent immunostaining to detect NETs, and clinical and outcome data were collected. Ex vivo and in vivo experiments were conducted. RESULTS: The numbers of NETs per myocardial tissue area and the proportion of NETs per neutrophil were significantly higher in patients with DCM compared with non-DCM control subjects without heart failure, and the numbers of NETs were negatively correlated with left ventricular ejection fraction. Patients with DCM with NETs (n=32) showed lower left ventricular ejection fraction and higher BNP (B-type natriuretic peptide) than those without NETs (n=30). In a multivariable Cox proportional hazard model, the presence of NETs was independently associated with an increased risk of adverse cardiac events in patients with DCM. To understand specific underlying mechanisms, extracellular flux analysis in ex vivo revealed that NETs-containing conditioned medium from wild-type neutrophils or purified NET components led to impaired mitochondrial oxygen consumption of cardiomyocytes, while these effects were abolished when PAD4 (peptidyl arginine deiminase 4) in neutrophils was genetically ablated. In a murine model of pressure overload, NETs in myocardial tissue were predominantly detected in the acute phase and persisted throughout the ongoing stress. Four weeks after transverse aortic constriction, left ventricular ejection fraction was reduced in wild-type mice, whereas PAD4-deficient mice displayed preserved left ventricular ejection fraction without inducing NET formation. CONCLUSIONS: NETs in myocardial tissue contribute to cardiac dysfunction and adverse outcomes in patients with heart failure with DCM, potentially through mitochondrial dysfunction of cardiomyocytes.

Collagen Triple Helix Repeat-Containing Protein 1 Is a Novel Biomarker of Right Ventricular Involvement in Pulmonary Hypertension.

BACKGROUND: Pulmonary hypertension leads to right ventricular failure, which is a major determinant of prognosis. Circulating biomarkers for right ventricular function are poorly explored in pulmonary hypertension. This study aimed to clarify the significance of collagen triple helix repeat-containing protein 1 (CTHRC1) as a biomarker of right ventricular failure in pulmonary hypertension. METHODS: A monocrotaline-induced pulmonary hypertension rat model was used to evaluate right ventricular CTHRC1 expression and its relationship with fibrosis. Next, human plasma CTHRC1 levels were measured in controls (n = 20), pulmonary arterial hypertension (n = 46), and patients with chronic thromboembolic pulmonary hypertension (CTEPH) (n = 64) before the first and after the final balloon pulmonary angioplasty. RESULTS: CTHRC1 expression was higher in the right ventricles of rats with monocrotaline-induced pulmonary hypertension than in those of controls. CTHRC1 was colocalized with vimentin and associated with fibrosis in the right ventricles. Plasma CTHRC1 levels were higher in human patients with pulmonary arterial hypertension (P = 0.006) and CTEPH (P = 0.011) than in controls. Plasma CTHRC levels were correlated with B-type natriuretic peptide (R = 0.355, P < 0.001), tricuspid lateral annular peak systolic velocity (R = -0.213, P = 0.029), and right ventricular fractional area change (R = -0.225, P = 0.017). Finally, plasma CTHRC1 levels were decreased after the final balloon pulmonary angioplasty (P < 0.001) in CTEPH. CONCLUSIONS: CTHRC1 can be a circulating biomarker associated with right ventricular function and fibrosis in pulmonary hypertension and might reflect the therapeutic efficacy of balloon pulmonary angioplasty in CTEPH.

Cathelicidin Antimicrobial Peptide LL37 Induces Toll-Like Receptor 8 and Amplifies IL-36γ and IL-17C in Human Keratinocytes.

LL37 is produced by skin injury and bacterial infection and plays an important role in the early stages of psoriasis. In particular, the intracellular receptors toll-like receptors (TLR)3, TLR7, TLR8, and TLR9 are thought to be involved in the pathogenesis of psoriasis in conjunction with LL37, but the interaction between TLR7/8 and LL37 in keratinocytes (KCs) remains unclear. This study aimed to clarify the relationship between LL37 and TLR7/8 in KCs and their involvement in the pathogenetic pathways seen in psoriasis using cultured KCs and skin samples of patients with psoriasis. TLR7/8 was induced by LL37 in KCs. TLR8 but not TLR7 functionally induced many psoriasis-related molecules, whereas IL-17C was not altered by the blockade of TLR7/8. Although costimulation of LL37 with self-RNA/DNA did not show any interaction, LL37 itself would promote psoriasis-related genes. IL-36 receptor antagonistic antibody suppressed IL-17C induced by LL37. In psoriatic epidermis, LL37, TLRs, IL-17C, and IL-36γ expressions were increased and coexpressed with each other. Thus, we concluded that LL37 activates TLR8 in KCs and induces IL-17C through the induction of IL-36γ. Regulation of TLR8 or LL37 in KCs could be a potential therapeutic strategy for psoriatic inflammation.

Prognostic Role of Circulating LTBP-2 in Patients With Dilated Cardiomyopathy: A Novel Biomarker Reflecting Extracellular Matrix LTBP-2 Accumulation.

BACKGROUND: Dilated cardiomyopathy (DCM) is a life-threatening disease related to heart failure. Extracellular matrix proteins have an important role in the pathogenesis of DCM. Latent transforming growth factor beta-binding protein 2 (LTBP-2), a type of extracellular matrix protein, has not been investigated in DCM. METHODS: First, we compared plasma LTBP-2 levels in 131 patients with DCM who underwent endomyocardial biopsy and 44 controls who were matched for age and sex and had no cardiac abnormalities. Next, we performed immunohistochemistry for LTBP-2 on endomyocardial biopsy specimens and followed the DCM patients for ventricular assist device (VAD) implantation, cardiac death, and all-cause death. RESULTS: Patients with DCM had elevated plasma LTBP-2 levels compared with controls (P < 0.001). Plasma LTBP-2 levels were positively correlated with LTBP-2-positive fraction in the myocardium from the biopsy specimen. When patients with DCM were divided into 2 groups according to LTBP-2 levels, Kaplan-Meier analysis demonstrated that patients with high plasma LTBP-2 were associated with increased incidences of cardiac death/VAD and all-cause death/VAD. In addition, patients with high myocardial LTBP-2-positive fractions were associated with increased incidences of these adverse outcomes. Multivariable Cox proportional hazard analysis showed that plasma LTBP-2 and myocardial LTBP-2-positive fraction were independently associated with adverse outcomes. CONCLUSIONS: Circulating LTBP-2 can serve as a biomarker to predict adverse outcomes, reflecting extracellular matrix LTBP-2 accumulation in the myocardium in DCM.