Single Cell MALDI-MS Imaging of Lipids and Proteins in Senescent Fibroblasts.

In this study, we evaluate the lipidomic and proteomic profiles of human lung fibroblasts (hLFs) to interrogate changes occurring due to senescence. To study single cell populations, a comparison of cell adhered onto slides utilizing poly-D-lysine versus centrifugal force deposition was first analyzed to determine whether specific alterations were observed between preparations. The poly-D-lysine approach was than utilized to interrogate the lipidome of the cell populations and further evaluate potential applications of the MALDI-IHC platform for single-cell level analyses. Altogether, our results show the ability to detect lipids implicated in senescence and alterations to protein expression between normal and senescent fibroblast populations. This report is the first time that the MALDI-IHC system has been utilized at a single-cell level for analyzing the expression of proteins.

RAB7 deficiency impairs pulmonary artery endothelial function and promotes pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in the development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health, and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from patients with PAH. Endothelial haploinsufficiency of RAB7 caused spontaneous pulmonary hypertension (PH) in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA-Seq, and RAB7-silenced ECs showed impaired angiogenesis and expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, suggesting inhibition of autophagy at the predegradation level. Furthermore, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in rats with chronic hypoxia/SU5416. In conclusion, we demonstrate for the first time to our knowledge the fundamental impairment of EC function by loss of RAB7, causing PH, and show RAB7 activation to be a potential therapeutic strategy in a preclinical model of PH.

LEF1 isoforms regulate cellular senescence and aging.

The study of aging and its mechanisms, such as cellular senescence, has provided valuable insights into age-related pathologies, thus contributing to their prevention and treatment. The current abundance of high-throughput data combined with the surge of robust analysis algorithms has facilitated novel ways of identifying underlying pathways that may drive these pathologies. For the purpose of identifying key regulators of lung aging, we performed comparative analyses of transcriptional profiles of aged versus young human subjects and mice, focusing on the common age-related changes in the transcriptional regulation in lung macrophages, T cells, and B immune cells. Importantly, we validated our findings in cell culture assays and human lung samples. Our analysis identified lymphoid enhancer binding factor 1 (LEF1) as an important age-associated regulator of gene expression in all three cell types across different tissues and species. Follow-up experiments showed that the differential expression of long and short LEF1 isoforms is a key regulatory mechanism of cellular senescence. Further examination of lung tissue from patients with idiopathic pulmonary fibrosis, an age-related disease with strong ties to cellular senescence, revealed a stark dysregulation of LEF1. Collectively, our results suggest that LEF1 is a key factor of aging, and its differential regulation is associated with human and murine cellular senescence.

LEF1 isoforms regulate cellular senescence and aging.

Background: The study of aging and its mechanisms, such as cellular senescence, has provided valuable insights into age-related pathologies, thus contributing to their prevention and treatment. The current abundance of high throughput data combined with the surge of robust analysis algorithms has facilitated novel ways of identifying underlying pathways that may drive these pathologies. Methods: With the focus on identifying key regulators of lung aging, we performed comparative analyses of transcriptional profiles of aged versus young human subjects and mice, focusing on the common age-related changes in the transcriptional regulation in lung macrophages, T cells, and B immune cells. Importantly, we validated our findings in cell culture assays and human lung samples. Results: We identified Lymphoid Enhancer Binding Factor 1 (LEF1) as an important age-associated regulator of gene expression in all three cell types across different tissues and species. Follow-up experiments showed that the differential expression of long and short LEF1 isoforms is a key regulatory mechanism of cellular senescence. Further examination of lung tissue from patients with Idiopathic Pulmonary Fibrosis (IPF), an age-related disease with strong ties to cellular senescence, we demonstrated a stark dysregulation of LEF1. Conclusions: Collectively, our results suggest that the LEF1 is a key factor of aging, and its differential regulation is associated with human and murine cellular senescence.

The aged extracellular matrix and the profibrotic role of senescence-associated secretory phenotype.

Idiopathic pulmonary fibrosis (IPF) is an irreversible and fatal lung disease that is primarily found in the elderly population, and several studies have demonstrated that aging is the major risk factor for IPF. IPF is characterized by the presence of apoptosis-resistant, senescent fibroblasts that generate an excessively stiff extracellular matrix (ECM). The ECM profoundly affects cellular functions and tissue homeostasis, and an aberrant ECM is closely associated with the development of lung fibrosis. Aging progressively alters ECM components and is associated with the accumulation of senescent cells that promote age-related tissue dysfunction through the expression of factors linked to a senescence-associated secretary phenotype (SASP). There is growing evidence that SASP factors affect various cell behaviors and influence ECM turnover in lung tissue through autocrine and/or paracrine signaling mechanisms. Since life expectancy is increasing worldwide, it is important to elucidate how aging affects ECM dynamics and turnover via SASP and thereby promotes lung fibrosis. In this review, we will focus on the molecular properties of SASP and its regulatory mechanisms. Furthermore, the pathophysiological process of ECM remodeling by SASP factors and the influence of an altered ECM from aged lungs on the development of lung fibrosis will be highlighted. Finally, recent attempts to target ECM alteration and senescent cells to modulate fibrosis will be introduced.NEW & NOTEWORTHY Aging is the most prominent nonmodifiable risk factor for various human diseases including Idiopathic pulmonary fibrosis. Aging progressively alters extracellular matrix components and is associated with the accumulation of senescent cells that promote age-related tissue dysfunction. In this review, we will discuss the pathological impact of aging and senescence on lung fibrosis via senescence-associated secretary phenotype factors and potential therapeutic approaches to limit the progression of lung fibrosis.

Early events marking lung fibroblast transition to profibrotic state in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is an age-associated progressive lung disease with accumulation of scar tissue impairing gas exchange. Previous high-throughput studies elucidated the role of cellular heterogeneity and molecular pathways in advanced disease. However, critical pathogenic pathways occurring in the transition of fibroblasts from normal to profibrotic have been largely overlooked. METHODS: We used single cell transcriptomics (scRNA-seq) from lungs of healthy controls and IPF patients (lower and upper lobes). We identified fibroblast subclusters, genes and pathways associated with early disease. Immunofluorescence assays validated the role of MOXD1 early in fibrosis. RESULTS: We identified four distinct fibroblast subgroups, including one marking the normal-to-profibrotic state transition. Our results show for the first time that global downregulation of ribosomal proteins and significant upregulation of the majority of copper-binding proteins, including MOXD1, mark the IPF transition. We find no significant differences in gene expression in IPF upper and lower lobe samples, which were selected to have low and high degree of fibrosis, respectively. CONCLUSIONS: Early events during IPF onset in fibroblasts include dysregulation of ribosomal and copper-binding proteins. Fibroblasts in early stage IPF may have already acquired a profibrotic phenotype while hallmarks of advanced disease, including fibroblast foci and honeycomb formation, are still not evident. The new transitional fibroblasts we discover could prove very important for studying the role of fibroblast plasticity in disease progression and help develop early diagnosis tools and therapeutic interventions targeting earlier disease states.

RAB7 deficiency impairs pulmonary artery endothelial function and promotes pulmonary hypertension.

Pulmonary arterial hypertension (PAH) is a devastating and progressive disease with limited treatment options. Endothelial dysfunction plays a central role in development and progression of PAH, yet the underlying mechanisms are incompletely understood. The endosome-lysosome system is important to maintain cellular health and the small GTPase RAB7 regulates many functions of this system. Here, we explored the role of RAB7 in endothelial cell (EC) function and lung vascular homeostasis. We found reduced expression of RAB7 in ECs from PAH patients. Endothelial haploinsufficiency of RAB7 caused spontaneous PH in mice. Silencing of RAB7 in ECs induced broad changes in gene expression revealed via RNA sequencing and RAB7 silenced ECs showed impaired angiogenesis, expansion of a senescent cell fraction, combined with impaired endolysosomal trafficking and degradation, which suggests inhibition of autophagy at the pre-degradation level. Further, mitochondrial membrane potential and oxidative phosphorylation were decreased, and glycolysis was enhanced. Treatment with the RAB7 activator ML-098 reduced established PH in chronic hypoxia/SU5416 rats. In conclusion, we demonstrate here for the first time the fundamental impairment of EC function by loss of RAB7 that leads to PH and show RAB7 activation as a potential therapeutic strategy in a preclinical model of PH.

CYB5R3 in type II alveolar epithelial cells protects against lung fibrosis by suppressing TGF-ß1 signaling.

Type II alveolar epithelial cell (AECII) redox imbalance contributes to the pathogenesis of idiopathic pulmonary fibrosis (IPF), a deadly disease with limited treatment options. Here, we show that expression of membrane-bound cytochrome B5 reductase 3 (CYB5R3), an enzyme critical for maintaining cellular redox homeostasis and soluble guanylate cyclase (sGC) heme iron redox state, is diminished in IPF AECIIs. Deficiency of CYB5R3 in AECIIs led to sustained activation of the pro-fibrotic factor TGF-ß1 and increased susceptibility to lung fibrosis. We further show that CYB5R3 is a critical regulator of ERK1/2 phosphorylation and the sGC/cGMP/protein kinase G axis that modulates activation of the TGF-ß1 signaling pathway. We demonstrate that sGC agonists (BAY 41-8543 and BAY 54-6544) are effective in reducing the pulmonary fibrotic outcomes of in vivo deficiency of CYB5R3 in AECIIs. Taken together, these results show that CYB5R3 in AECIIs is required to maintain resilience after lung injury and fibrosis and that therapeutic manipulation of the sGC redox state could provide a basis for treating fibrotic conditions in the lung and beyond.

scResolve: Recovering single cell expression profiles from multi-cellular spatial transcriptomics.

Many popular spatial transcriptomics techniques lack single-cell resolution. Instead, these methods measure the collective gene expression for each location from a mixture of cells, potentially containing multiple cell types. Here, we developed scResolve, a method for recovering single-cell expression profiles from spatial transcriptomics measurements at multi-cellular resolution. scResolve accurately restores expression profiles of individual cells at their locations, which is unattainable from cell type deconvolution. Applications of scResolve on human breast cancer data and human lung disease data demonstrate that scResolve enables cell type-specific differential gene expression analysis between different tissue contexts and accurate identification of rare cell populations. The spatially resolved cellular-level expression profiles obtained through scResolve facilitate more flexible and precise spatial analysis that complements raw multi-cellular level analysis.

Calidad de vida y balance sagital en la evolución de los pacientes con mieloma múltiple tratados con vertebroplastia percutánea / Quality of Life and Sagittal Balance in the Evolution of Patients with Multiple Myeloma Who Received Treatment

RESUMEN Introducción: El mieloma múltiple representa el 1 por ciento de las neoplasias y el 10 por ciento de las hemopatías malignas. La edad media de presentación es 65 años. El dolor óseo en columna vertebral y costillas constituye su manifestación inicial. El tratamiento quirúrgico del mieloma múltiple en la columna consiste en descompresión amplia y artrodesis. La vertebroplastia se considera técnica de elección porque restablece el balance sagital y coronal, contribuye al fortalecimiento del cuerpo vertebral, y disminuye el dolor asociado a fracturas. Objetivo: Evaluar el efecto de la vertebroplastia sobre la calidad de vida y el balance sagital, en la disminución del dolor. Métodos: Se estudiaron 192 pacientes con mieloma múltiple con fractura en la columna, 80 tratados con vertebroplastia y 112 en forma conservadora. Se utilizó el cuestionario de Oswestry y la escala de Karnosfky. Resultados: La vertebroplastia disminuyó 0,52 veces el uso de analgésicos opioides. Conclusiones: La vertebroplastia representa un mayor beneficio de la calidad de vida de los pacientes aquejados de mieloma múltiple con fractura vertebral; repercute en el mejoramiento del balance sagital, el nivel de discapacidad y la capacidad para realizar tareas cotidianas(AU)

ABSTRACT Introduction: Multiple myeloma accounts for 1 percent of neoplasms and for 10 percent of malignant hematomas. The mean onset age is 65 years. Bone pain in the spine and ribs is its initial manifestation. Surgical treatment for multiple myeloma in the spine consists in wide decompression and arthrodesis. Vertebroplasty is considered the choice technique because it restores sagittal and coronal balance, contributes to the strengthening of the vertebral body, and reduces pain associated with fractures. Objective: To assess the effect of vertebroplasty on quality of life and the effect of sagittal balance in reducing pain. Methods: 192 patients with multiple myeloma and spinal fracture were studied, 80 treated with vertebroplasty and 112 treated conservatively. The Oswestry questionnaire and the Karnofsky scale were used. Results: Vertebroplasty decreased the use of opioid analgesics by 0.52 times. Conclusions: Vertebroplasty represents a greater benefit for the quality of life of patients suffering from multiple myeloma with vertebral fracture. It affects the improvement of sagittal balance, the level of disability, and the ability to perform daily tasks(AU)

Disease duration of rheumatoid arthritis is a predictor of vascular stiffness: a cross-sectional study in patients without known cardiovascular comorbidities: A STROBE-compliant article.

The aim of this study was to analyze the impact of disease duration on carotid to femoral pulse wave velocity (cfPWV) in rheumatoid arthritis (RA) patients without either known traditional cardiovascular risk factors or previous comorbidities.Patients with RA diagnosis attending the rheumatology outpatient clinic of Hospital Civil Juan I. Menchaca, Guadalajara, Mexico, were analyzed. A total of 106 RA patients without known traditional cardiovascular risk factors were selected. All subjects were evaluated for RA disease duration, RA disease activity score on 28 joints (DAS28), serum lipids, rheumatoid factor and anti-cyclic citrullinated peptide (anti-CCP) antibodies. Arterial stiffness was measured as cfPWV by noninvasive tonometry. A multivariate regression model was used to analyze the contribution of RA disease duration and age on cfPWV. cfPWV was positively correlated with age (r = 0.450, P < .001), RA disease duration (r = 0.340, P < .001), total cholesterol (r = 0.312, P = .002), and low density lipoprotein (LDL-c) cholesterol (r = 0.268, P = .012). Patients with a RA disease duration ≥10 years exhibited significantly increased cfPWV compared with patients with disease duration <2 years (8.4 ±â€Š1.8 vs 7.0 ±â€Š0.8) and ≥2 to <10 years (8.4 ±â€Š1.8 vs 7.8 ±â€Š1.3), respectively. Age, RA disease duration, and triglycerides were predictors of cfPWV in multivariate analyses. According to the ß-coefficients, each year of disease duration (ß = 0.072) had a greater impact on cfPWV than age (ß = 0.054).Each year of life with RA contributes to a higher rate of vascular aging or stiffening than a year of life without RA. The cumulative damage provided by RA was most pronounced in patients with disease duration ≥10 years.

Detection of autoantibodies to DSF70/LEDGFp75 in Mexican Hispanics using multiple complementary assay platforms.

PURPOSE: Antinuclear autoantibodies (ANA) targeting the dense fine speckled antigen DFS70, also known as lens epithelium-derived growth factor p75 (LEDGF/p75), are attracting attention due to their low frequency in systemic rheumatic diseases but increased frequency in clinical laboratory referrals and healthy individuals (HI). These ANA specifically recognize the stress protein DFS70/LEDGFp75, implicated in cancer, HIV-AIDS, and inflammation. While their frequency has been investigated in various ethnic populations, there is little information on their frequency among Hispanics/Latinos. In this study, we determined the frequency of anti-DFS70/LEDGFp75 autoantibodies in Mexican Hispanics using multiple detection platforms. METHODS: The frequency of anti-DFS70/LEDGFp75 antibodies was determined in 171 individuals, including 71 dermatomyositis (DM) patients, 47 rheumatoid arthritis (RA) patients, 30 obesity (OB) patients, and 23 HI. Antibody detection was achieved using four complementary assay platforms: indirect immunofluorescence, Western blotting, ELISA, and chemiluminescent immunoassay. RESULTS: We detected relatively low frequencies of anti-DFS70/LEDGFp75 antibodies in patients with DM (1.4%), RA (4.3%), and OB (6.6%), and elevated frequency (17.4%) in HI. A strong concordance between the different antibody detection platforms was observed. CONCLUSIONS: The low frequency of anti-DFS70/LEDGFp75 antibodies in Mexican patients with rheumatic diseases, but relatively higher frequency in HI, is consistent with previous observations with non-Hispanic populations, suggesting that geographic differences or ethnicity do not influence the frequency of these autoantibodies. Our results also highlight the importance of confirmatory assays for the accurate detection of these autoantibodies. Future studies with larger cohorts of healthy Hispanics/Latinos are needed to confirm if their anti-DFS70/LEDGFp75 antibody frequencies are significantly higher than in non-Hispanics.

Evaluación de la efectividad de un método de medición directa sobre modelos para arco maxilar en pacientes sanos y pacientes con labio y paladar fisurado unilateral izquierdo completo de los 4 a 7 meses de edad / Maxillar arches in healthy patients

En este estudio se buscó establecer la confiabilidad de 33 modelos de arcos maxilares de pacientes sanos y 18 en pacientes con labio y paladar fisurado unilateralmente completo izquierdo en edades de 4 a 7 meses de edad, pertenecientes a la clínica odontológica de la Escuela Colombiana de Medicina en el Hospital Infantil Lorencita de Villegas de Santos. Se usó un método de Medición estandarizado llevado a cabo por 5 examinadores, y comparando así el promedio de cada medida se observó que es un método confiable en las medidas donde el valor P de A, C, D, E,=>0.05; y no fué confiable en puntos de referencia de difícil localización como es el largo y el ancho de la fisura en pacientes con labio y paladar fisurado unilateral completo izquierdo