Photobiomodulation of human dermal fibroblasts in vitro: decisive role of cell culture conditions and treatment protocols on experimental outcome

YesPhotobiomodulation-based (LLLT) therapies show tantalizing promise for treatment of skin diseases. Confidence in this approach is blighted however by lamentable inconsistency in published experimental designs, and so complicates interpretation. Here we interrogate the appropriateness of a range of previously-reported treatment parameters, including light wavelength, irradiance and radiant exposure, as well as cell culture conditions (e.g., serum concentration, cell confluency, medium refreshment, direct/indirect treatment, oxygen concentration, etc.), in primary cultures of normal human dermal fibroblasts exposed to visible and near infra-red (NIR) light. Apart from irradiance, all study parameters impacted significantly on fibroblast metabolic activity. Moreover, when cells were grown at atmospheric O2 levels (i.e. 20%) short wavelength light inhibited cell metabolism, while negligible effects were seen with long visible and NIR wavelength. By contrast, NIR stimulated cells when exposed to dermal tissue oxygen levels (approx. 2%). The impact of culture conditions was further seen when inhibitory effects of short wavelength light were reduced with increasing serum concentration and cell confluency. We conclude that a significant source of problematic interpretations in photobiomodulation reports derives from poor optimization of study design. Further development of this field using in vitro/ex vivo models should embrace significant standardization of study design, ideally within a design-of-experiment setting

Does blue light restore human epidermal barrier function via activation of Opsin during cutaneous wound healing?

YesBackground and Objective Visible light has beneficial effects on cutaneous wound healing, but the role of potential photoreceptors in human skin is unknown. In addition, inconsistency in the parameters of blue and red light‐based therapies for skin conditions makes interpretation difficult. Red light can activate cytochrome c oxidase and has been proposed as a wound healing therapy. UV‐blue light can activate Opsin 1‐SW, Opsin 2, Opsin 3, Opsin 4, and Opsin 5 receptors, triggering biological responses, but their role in human skin physiology is unclear. Materials and Methods Localization of Opsins was analyzed in situ in human skin derived from face and abdomen by immunohistochemistry. An ex vivo human skin wound healing model was established and expression of Opsins confirmed by immunohistochemistry. The rate of wound closure was quantitated after irradiation with blue and red light and mRNA was extracted from the regenerating epithelial tongue by laser micro‐dissection to detect changes in Opsin 3 (OPN3) expression. Retention of the expression of Opsins in primary cultures of human epidermal keratinocytes and dermal fibroblasts was confirmed by qRT‐PCR and immunocytochemistry. Modulation of metabolic activity by visible light was studied. Furthermore, migration in a scratch‐wound assay, DNA synthesis and differentiation of epidermal keratinocytes was established following irradiation with blue light. A role for OPN3 in keratinocytes was investigated by gene silencing. Results Opsin receptors (OPN1‐SW, 3 and 5) were similarly localized in the epidermis of human facial and abdominal skin in situ. Corresponding expression was confirmed in the regenerating epithelial tongue of ex vivo wounds after 2 days in culture, and irradiation with blue light stimulated wound closure, with a corresponding increase in OPN3 expression. Expression of Opsins was retained in primary cultures of epidermal keratinocytes and dermal fibroblasts. Both blue and red light stimulated the metabolic activity of cultured keratinocytes. Low levels of blue light reduced DNA synthesis and stimulated differentiation of keratinocytes. While low levels of blue light did not alter keratinocyte migration in a scratch wound assay, higher levels inhibited migration. Gene silencing of OPN3 in keratinocytes was effective (87% reduction). The rate of DNA synthesis in OPN3 knockdown keratinocytes did not change following irradiation with blue light, however, the level of differentiation was decreased. Conclusions Opsins are expressed in the epidermis and dermis of human skin and in the newly regenerating epidermis following wounding. An increase in OPN3 expression in the epithelial tongue may be a potential mechanism for the stimulation of wound closure by blue light. Since keratinocytes and fibroblasts retain their expression of Opsins in culture, they provide a good model to investigate the mechanism of blue light in wound healing responses. Knockdown of OPN3 led to a reduction in early differentiation of keratinocytes following irradiation with blue light, suggesting OPN3 is required for restoration of the barrier function. Understanding the function and relationship of different photoreceptors and their response to specific light parameters will lead to the development of reliable light‐based therapies for cutaneous wound healing.European Commission 7th Framework Programme for Research and Technical Development - Marie Curie Innovative Training Networks (ITN), Grant agreement no.: 60788

Comprehensive Cardiovascular Magnetic Resonance‐Derived Myocardial Strain Analysis Provides Independent Prognostic Value in Acute Myocarditis

Background Late gadolinium enhancement and left ventricular (LV) ejection fraction on cardiovascular magnetic resonance (CMR) are prognostic markers, but their predictive value for incident heart failure or life‐threatening arrhythmias in acute myocarditis patients is limited. CMR‐derived feature tracking provides a more sensitive analysis of myocardial function and may improve risk stratification in myocarditis. In this study, the prognostic value of LV, right ventricular, and left atrial strain in acute myocarditis patients is evaluated. Methods and Results In this multicenter retrospective study, patients with CMR‐proven acute myocarditis were included. The primary end point was occurrence of major adverse cardiovascular events: all‐cause mortality, heart transplantation, heart failure hospitalizations, and life threatening arrhythmias. LV global longitudinal strain, global circumferential strain and global radial strain, right ventricular‐global longitudinal strain and left atrial strain were measured. Unadjusted and adjusted cox proportional hazard regression analysis were performed. In total, 162 CMR‐proven myocarditis patients were included (41 ± 17 years, 75% men). Mean LV ejection fraction was 51 ± 12%, and 144 (89%) patients had presence of late gadolinium enhancement. Major adverse cardiovascular events occurred in 29 (18%) patients during a follow‐up of 5.5 (2.2–8.3) years. All LV strain parameters were independent predictors of outcome beyond clinical features, LV ejection fraction and late gadolinium enhancement (LV‐global longitudinal strain: hazard ratio [HR] 1.07, P=0.02; LV‐global circumferential strain: HR 1.15, P=0.02; LV‐global radial strain: HR 0.98, P=0.03), but right ventricular or left atrial strain did not predict outcome. Conclusions CMR‐derived LV strain analysis provides independent prognostic value on top of clinical parameters, LV ejection fraction and late gadolinium enhancement in acute myocarditis patients, while left atrial and right ventricular strain seem to be of less importance

Comprehensive Cardiovascular Magnetic Resonance-Derived Myocardial Strain Analysis Provides Independent Prognostic Value in Acute Myocarditis

Background Late gadolinium enhancement and left ventricular (LV) ejection fraction on cardiovascular magnetic resonance (CMR) are prognostic markers, but their predictive value for incident heart failure or life-threatening arrhythmias in acute myocarditis patients is limited. CMR-derived feature tracking provides a more sensitive analysis of myocardial function and may improve risk stratification in myocarditis. In this study, the prognostic value of LV, right ventricular, and left atrial strain in acute myocarditis patients is evaluated. Methods and Results In this multicenter retrospective study, patients with CMR-proven acute myocarditis were included. The primary end point was occurrence of major adverse cardiovascular events: all-cause mortality, heart transplantation, heart failure hospitalizations, and life threatening arrhythmias. LV global longitudinal strain, global circumferential strain and global radial strain, right ventricular-global longitudinal strain and left atrial strain were measured. Unadjusted and adjusted cox proportional hazard regression analysis were performed. In total, 162 CMR-proven myocarditis patients were included (41 ± 17 years, 75% men). Mean LV ejection fraction was 51 ± 12%, and 144 (89%) patients had presence of late gadolinium enhancement. Major adverse cardiovascular events occurred in 29 (18%) patients during a follow-up of 5.5 (2.2-8.3) years. All LV strain parameters were independent predictors of outcome beyond clinical features, LV ejection fraction and late gadolinium enhancement (LV-global longitudinal strain: hazard ratio [HR] 1.07, P=0.02; LV-global circumferential strain: HR 1.15, P=0.02; LV-global radial strain: HR 0.98, P=0.03), but right ventricular or left atrial strain did not predict outcome. Conclusions CMR-derived LV strain analysis provides independent prognostic value on top of clinical parameters, LV ejection fraction and late gadolinium enhancement in acute myocarditis patients, while left atrial and right ventricular strain seem to be of less importance

Left Atrial Reverse Remodeling in Dilated Cardiomyopathy

BACKGROUND: Left atrial (LA) dilation is associated with a worse prognosis in several cardiovascular settings but therapies can promote LA reverse remodeling. We aimed to characterize and define the prognostic implications of LA volume (LAVI) reduction in dilated cardiomyopathy (DCM). METHODS: Consecutive DCM patients from two tertiary care centers, with available echocardiography at baseline and at 1-year follow-up, were retrospectively analyzed. LA dilation was defined as LAVI >34 ml/m2, change in LAVI (ΔLAVI) was defined as the 1-year relative LAVI reduction. The outcome was a composite of death/heart transplantation/heart failure hospitalization (D/HTx/HFH). RESULTS: Five hundred sixty patients were included (age 54±13 years; left ventricular ejection fraction (LVEF) 31±10%, LAVI 45±18 ml/m2). Baseline LAVI had a non-linear association with the risk of D/HTx/HFH, independently from age, LVEF, MR and medical therapy (p<0.01). At 1-year follow-up, LAVI decreased in 374 patients (67%, median ΔLAVI -24%, interquartile range -37% - -11%). Factors independently associated with ΔLAVI were higher baseline LAVI and lower baseline LVEF. After multivariable adjustment, ΔLAVI showed a linear association with the risk of D/HTx/HFH (HR 0.96, 95% 0.93-0.99 per 5% decrease, p=0.042). At 1-year follow-up, patients with a reduction in LAVI greater than 10% and LAVI normalization (i.e. follow-up LAVI ≤34ml/m2) (31% of the overall cohort) were at lower risk of D/HTx/HFH (HR 0.37, 95% C.I. 0.35-0.97, p=0.028). CONCLUSIONS: In a large cohort of DCM, 1-year reduction in LAVI is observed in a number of patients. The association between reduction in LAVI and D/HTx/HFH suggests that LA structural reverse remodeling might be considered an additional parameter useful in the individualized risk stratification of patients with DCM

Intravenous immunoglobulin therapy in adult patients with idiopathic chronic cardiomyopathy and cardiac parvovirus B19 persistence: a prospective, double-blind, randomized, placebo-controlled clinical trial

Aims Previous uncontrolled studies suggested a possible benefit of intravenous immunoglobulin (IVIg) in parvovirus B19 (B19V)-related dilated cardiomyopathy (DCM). This randomized, double-blind, placebo-controlled, single-centre trial investigated the benefits of IVIg beyond conventional therapy in idiopathic chronic DCM patients with B19V persistence.Methods and results Fifty patients (39 men; mean age 54 +/- 11 years) with idiopathic chronic (>6 months) DCM on optimal medical therapy, left ventricular ejection fraction (LVEF) 200 copies/mu g DNA were blindly randomized to either IVIg (n = 26, 2 g/kg over 4 days) or placebo (n = 24). The primary outcome was change in LVEF at 6 months after randomization. Secondary outcomes were change in functional capacity assessed by 6-min walk test (6MWT), quality of life [Minnesota Living with Heart Failure Questionnaire (MLHFQ)], left ventricular end-diastolic volume (LVEDV), and EMB B19V load at 6 months after randomization. LVEF significantly improved in both IVIg and placebo groups (absolute mean increase 5 +/- 9%, P = 0.011 and 6 +/- 10%, P = 0.008, respectively), without a significant difference between groups (P = 0.609). Additionally, change in 6MWT [median (interquartile range) IVIg 36 (13;82) vs. placebo 32 (5;80) m; P = 0.573], MLHFQ [IVIg 0 (-7;5) vs. placebo -2 (-6;6), P = 0.904] and LVEDV (IVIg -16 +/- 49 mL/m(2) vs. placebo -29 +/- 40 mL/m(2); P = 0.334) did not significantly differ between groups. Moreover, despite increased circulating B19V antibodies upon IVIg administration, reduction in cardiac B19V did not significantly differ between groups.Conclusion Intravenous immunoglobulin therapy does not significantly improve cardiac systolic function or functional capacity beyond standard medical therapy in patients with idiopathic chronic DCM and cardiac B19V persistence

Left Atrial Strain Has Superior Prognostic Value to Ventricular Function and Delayed-Enhancement in Dilated Cardiomyopathy

BACKGROUND: The left atrium is an early sensor of left ventricular (LV) dysfunction. Still, the prognostic value of left atrial (LA) function (strain) on cardiac magnetic resonance (CMR) in dilated cardiomyopathy (DCM) remains unknown. OBJECTIVES: The goal of this study was to evaluate the prognostic value of CMR-derived LA strain in DCM. METHODS: Patients with DCM from the Maastricht Cardiomyopathy Registry with available CMR imaging were included. The primary endpoint was the combination of sudden or cardiac death, heart failure (HF) hospitalization, or life-threatening arrhythmias. Given the nonlinearity of continuous variables, cubic spline analysis was performed to dichotomize. RESULTS: A total of 488 patients with DCM were included (median age: 54 [IQR: 46-62] years; 61% male). Seventy patients (14%) reached the primary endpoint (median follow-up: 6 [IQR: 4-9] years). Age, New York Heart Association (NYHA) functional class >II, presence of late gadolinium enhancement (LGE), LV ejection fraction (LVEF), LA volume index (LAVI), LV global longitudinal strain (GLS), and LA reservoir and conduit strain were univariably associated with the outcome (all P II, and LGE remained associated in the multivariable model (LA conduit strain HR: 3.65 [95% CI: 2.01-6.64; P II HR: 1.81 [95% CI: 1.05-3.12; P = 0.033]; and LGE HR: 2.33 [95% CI: 1.42-3.85; P < 0.001]), whereas age, N-terminal pro-B-type natriuretic peptide, LVEF, left atrial ejection fraction, LAVI, and LV GLS were not. Adding LA conduit strain to other independent predictors (NYHA functional class and LGE) significantly improved the calibration, accuracy, and reclassification of the prediction model (P < 0.05). CONCLUSIONS: LA conduit strain on CMR is a strong independent prognostic predictor in DCM, superior to LV GLS, LVEF, and LAVI and incremental to LGE. Including LA conduit strain in DCM patient management should be considered to improve risk stratification

Left Atrial Reverse Remodeling in Dilated Cardiomyopathy

Background: Left atrial (LA) dilation is associated with a worse prognosis in several cardiovascular settings, but therapies can promote LA reverse remodeling. The aim of this study was to characterize and define the prognostic implications of LA volume index (LAVI) reduction in patients with dilated cardiomyopathy (DCM). Methods: Consecutive patients with DCM from two tertiary care centers, with available echocardiograms at baseline and at 1-year follow-up, were retrospectively analyzed. LA dilation was defined as LAVI &gt; 34 mL/m2, and change in LAVI (ΔLAVI) was defined as the 1-year relative LAVI reduction. The outcome was a composite of death, heart transplantation (HTx), or heart failure hospitalization (HFH). Results: Five hundred sixty patients were included (mean age, 54 ± 13 years; mean left ventricular ejection fraction, 31 ± 10%; mean LAVI, 45 ± 18 mL/m2). Baseline LAVI had a non-linear association with the risk for death, HTx, or HFH, independent of age, left ventricular ejection fraction, mitral regurgitation, and medical therapy (P &lt; .01). At 1-year follow-up, LAVI decreased in 374 patients (67%; median ΔLAVI, −24%; interquartile range, −37% to −11%). Factors independently associated with ΔLAVI were higher baseline LAVI and lower baseline left ventricular ejection fraction. After multivariable adjustment, ΔLAVI showed a linear association with the risk for death, HTx, or HFH (hazard ratio, 0.96 per 5% decrease; 95% CI, 0.93-0.99; P = .042). At 1-year follow-up, patients with reductions in LAVI of &gt;10% and LAVI normalization (i.e., follow-up LAVI ≤ 34 mL/m2; 31% of the overall cohort) were at lower risk for death, HTx, or HFH (hazard ratio, 0.37; 95% CI, 0.35-0.97; P = .028). Conclusions: In a large cohort of patients with DCM, 1-year reduction in LAVI was observed in a number of patients. The association between reduction in LAVI and death, HTx, or HFH suggests that LA structural reverse remodeling might be considered an additional parameter useful in the individualized risk stratification of patients with DCM

Global Longitudinal Strain is Incremental to Left Ventricular Ejection Fraction for the Prediction of Outcome in Optimally Treated Dilated Cardiomyopathy Patients

Background Speckle tracking echocardiographic global longitudinal strain (GLS) predicts outcome in patients with new onset heart failure. Still, its incremental value on top of left ventricular ejection fraction (LVEF) in patients with nonischemic, nonvalvular dilated cardiomyopathy (DCM) after optimal heart failure treatment remains unknown. Methods and Results Patients with DCM were included at the outpatient clinics of 2 centers in the Netherlands and Italy. The prognostic value of 2-dimensional speckle tracking echocardiographic global longitudinal strain was evaluated when being on optimal heart failure medication for at least 6 months. Outcome was defined as the combination of sudden or cardiac death, life-threatening arrhythmias, and heart failure hospitalization. A total of 323 patients with DCM (66% men, age 55±14 years) were included. The mean LVEF was 42%±11% and mean GLS after optimal heart failure treatment was -15%±4%. Twenty percent (64/323) of all patients reached the primary outcome after optimal heart failure treatment (median follow-up of 6[4-9] years). New York Heart Association class ≥3, LVEF, and GLS remained associated with the outcome in the multivariable-adjusted model (New York Heart Association class: hazard ratio [HR], 3.43; 95% CI, 1.49-7.90, P=0.004; LVEF: HR, 2.13; 95% CI, 1.11-4.10, P=0.024; GLS: HR, 2.24; 95% CI, 1.18-4.29, P=0.015), whereas left ventricular end-diastolic diameter index, left atrial volume index, and delta GLS were not. The addition of GLS to New York Heart Association class and LVEF improved the goodness of fit (log likelihood ratio test P<0.001) and discrimination (Harrell's C 0.703). Conclusions Within this bicenter study, GLS emerged as an independent and incremental predictor of adverse outcome, which exceeded LVEF in patients with optimally treated DCM. This presses the need to routinely include GLS in the echocardiographic follow-up of DCM