Fibrillin-1 Research Articles

Targeted genetic analysis in a cohort of sporadic death from spontaneous rupture of thoracic aortic dissection in Han Chinese population

PurposeThoracic aortic dissection (TAD) is a life-threatening cardiovascular disease that often results in sudden cardiac death (SCD). However, the genetic characteristics of individuals with TAD confirmed at autopsy have been rarely studied. Our objective was to determine the prevalence of pathogenic variants in TAD-associated genes in a cohort of sporadic deaths resulting from spontaneous rupture of TAD and identify relevant genotype-phenotype relationships in Han Chinese population. MethodsWe included sixty-one consecutive sporadic decedents whose primary cause of death was spontaneous rupture of TAD, and performed a whole exome sequencing based strategy comprising 26 known TAD-associated genes. ResultsWe identified 7 pathogenic or likely pathogenic (P/LP) variants in 7 cases (11.48 %) and 22 variants of uncertain significance (VUS) in 22 cases (36.07 %). The FBN1 gene was found to be the major disease-causing gene. Notably, TAD decedents with P/LP variant exhibited significantly earlier mortality. Moreover, we reported for the first time that TAD decedents with P/LP variant had a shorter diagnosis and treatment time. ConclusionOur study investigated the genetic characteristics of TAD individuals confirmed until autopsy in Han Chinese population. The findings enhanced the understanding of the genetic underpinnings of TAD and have significant implications for clinical management and forensic investigations.

FBN2 pathogenic variants in congenital contractural arachnodactyly with severe cardiovascular manifestations

ABSTRACT Purpose Congenital contractural arachnodactyly (CCA) is an extremely rare autosomal dominant connective tissue genetic disorder caused by pathogenic variants in FBN2. CCA is characterized by arachnodactyly, camptodactyly, contracture of major joints, scoliosis, pectus deformities, and crumpled ears, but rarely with lethal cardiovascular manifestations as in Marfan syndrome. It is imperative to conduct a comprehensive analysis and review of the pathogenesis of CCA resulting from pathogenic variants in FBN2 gene. Materials and Methods Using whole-exome sequencing and Sanger sequencing, we identified a novel pathogenic splice-altering variant (c.4472-3C>A) in intron 34 of FBN2 gene in a CCA pedigree. The transcriptional result of the splicing-altering variant was analyzed by RNA sequencing. We systematically analyzed the clinical manifestations of all reported cases of CCA caused by splicing-altering pathogenic variants and focused on all the pathogenic variants in FBN2 gene that are associated with severe cardiovascular manifestations. Results The splice-altering variant (c.4472-3C>A) in FBN2 was demonstrated to result in the exon 35 skipping and cause an in-frame deletion. Furthermore, we identified exons 31 to 35 may be a hotspot region in FBN2 gene associated with severe cardiovascular phenotype. Conclusions This study enriched the pathogenic spectrum of CCA and identified a hotspot region in FBN2 gene associated with severe cardiovascular manifestations. We recommend that patients carrying pathogenic variants in exons 31 to 35 of FBN2 pay more attention to cardiac evaluation.

Effect of Fibrillin-2 on Differentiation into Periodontal Ligament Stem Cell-Like Cells Derived from Human-Induced Pluripotent Stem Cells.

Periodontal tissue regeneration is important for preserving teeth. Periodontal ligament stem cells (PDLSCs) are useful in periodontal tissue regeneration; however, tooth extraction is required to obtain these cells. Therefore, we focused on induced pluripotent stem (iPS) cells and established a method to obtain PDLSC-like cells from iPS cells. Specifically, we first differentiated iPS cells into neural crest-like cells (iNCs). Next, we obtained PDLSC-like cells (iPDLSCs) by culturing iNCs on extracellular matrix (ECM) derived from human primary periodontal ligament cells (HPDLCs). This differentiation method suggested that ECM derived from HPDLCs is important for iPDLSC differentiation. Thus, we aimed to identify the PDLSC-inducing factor present in HPDLC-derived ECM in this study. We first performed comprehensive analyses of HPDLC genes and identified fibrillin-2 (FBN2), an ECM-related factor. Furthermore, to clarify the effect of FBN2 on iPDLSC differentiation, we cultured iNCs using ECM derived from HPDLCs with FBN2 knocked down. As a result, expression of PDL-related markers was reduced in iNCs cultured on ECM derived from HPDLCs transfected with FBN2 siRNA (iNC-siFBN2) compared with iPDLSCs. Furthermore, the expression of CD105 (a mesenchymal stem cell marker), proliferation ability, and multipotency of iNC-siFBN2 were lower compared with iPDLSCs. Next, we cultured iNCs on FBN2 recombinant protein; however, expression of PDL-related markers did not increase compared with iPDLSC. The present results suggest the critical involvement of FBN2 in inducing iPDLSCs from iNCs when in fact it does not promote iPDLSC differantiation. Therefore, we need to elucidate the entire HPDLC-ECMs, responsible for iPDLSCs induction.

Genotype-phenotype Correlations of Ocular Posterior Segment Abnormalities in Marfan Syndrome

PurposeMarfan syndrome (MFS) is a connective tissue disorder caused by mutations in the FBN1 gene. In addition to typical phenotypes such as ectopia lentis and aortic dilation, MFS patients are prone to ocular posterior segment abnormalities, including retinal detachment, maculopathy, and posterior staphyloma. This study aims to investigate the correlations between FBN1 genotype and posterior segment abnormalities within a Chinese cohort of MFS. DesignRetrospective study. Participants121 eyes of 121 patients with confirmed FBN1 mutations between January 2015 and May 2023 were included. MethodsComprehensive ophthalmological exam findings were reviewed, and the incidence of retinal detachment, atrophic / tractional / neovascular maculopathy (ATN classification system) and posterior staphyloma was analyzed between different genotype groups. Only the more severely affected eye from each patient was included. Main outcome measuresClinical features and risk factors. ResultsOut of 121 patients, 60 eyes (49.59%) exhibited posterior segment abnormalities, including retinal detachment (4, 3.31%), maculopathy (47, 38.84%), and posterior staphyloma (54, 44.63%). The mean age was 11.53 ± 11.66 years, with 79.34% of patients below 20 years old. The location and region of mutations were found to be associated with the incidence of maculopathy (P = 0.013, P = 0.033) and posterior staphyloma (P = 0.043, P = 0.036). Mutations in the middle region had a lower incidence of maculopathy and posterior staphyloma (P = 0.028 and P = 0.006, respectively) than those in C-terminal region. Mutations in the TGF-β regulating sequence exhibited a higher incidence of maculopathy and posterior staphyloma (P = 0.020, P = 0.040). Importantly, the location and region of mutations were also associated with the incidence of atrophic maculopathy (P = 0.013 and P = 0.033, respectively). Mutations in the middle region had a significantly lower probability of atrophic maculopathy (P = 0.006), while mutations in the TGF-β regulating sequence had a higher incidence of atrophic maculopathy (P = 0.020). ConclusionMaculopathy and posterior staphyloma were associated with the location and region of FBN1 mutations. Patients with mutations in the TGF-β regulating sequence faced an increased risk of developing retinopathy.

Marfan Syndrome with Atypical Pneumonia: A Case Report

Marfan syndrome (MFS) is an autosomal dominant systemic disorder of the connective tissue. Children impacted by the MFS carry the mutation in one of their two alleles of the gene that codes the connective tissue protein fibrillin-1 (FBN-1). MFS influences their effects upon most organs and tissues, in particular the skeleton, lungs, eyes, heart, and the large blood vessel that distributes blood from the heart to the reminder of the physique. A case report of MFS with atypical pneumonia has been reported with positive Steinberg sign, thumb sign and wrist sign. Existence of long legs with the positive Walker Murdoch sign. There were no complications such as an aortic aneurysm, ocular lens luxation, or mitral valve prolapse were remarked. Since the patient was lacking such complications based on MFS, he was treated only for atypical pneumonia. Keywords: Marfan Syndrome, Fibrillin-1, Thoracic Aortic Aneurysm or Dissection, Ectopia Lentis

The usefulness of the genetic panel in the classification and refinement of diagnostic accuracy of Mexican patients with Marfan syndrome and other connective tissue disorders.

Marfan syndrome (MFS) is a multisystem genetic disorder with over 3000 mutations described in the fibrillin 1 (FBN1) gene. Like MFS, other connective tissue disorders also require a deeper understanding of the phenotype-genotype relationship due to the complexity of the clinical presentation, where diagnostic criteria often overlap. Our objective was to identify mutations in patients with connective tissue disorders using a genetic multipanel and to analyze the genotype-phenotype associations in a cohort of Mexican patients. We recruited 136 patients with MFS and related syndromes from the National Institute of Cardiology. Mutations were identified using next-generation sequencing (NGS). To examine the correlation between mutation severity and severe cardiovascular conditions, we focused on patients who had undergone Bentall-de Bono surgery or aortic valve repair. The genetic data obtained allowed us to reclassify the initial clinical diagnosis across various types of connective tissue disorders. The transforming growth factor beta receptor 2 (TGFBR2) rs79375991 mutation was found in 10 out of 16 (63%) Loeys-Dietz patients. We observed a high prevalence (65%) of more severe mutations, such as frameshift indels and stop codons, among patients requiring invasive treatments like aortic valve-sparing surgery, Bentall and de Bono procedures, or aortic valve replacement due to severe cardiovascular injury. Although our study did not achieve precise phenotype-genotype correlations, it underscores the importance of a multigenetic panel evaluation. This could pave the way for a more comprehensive diagnostic approach and inform medical and surgical treatment decision-making.

Clinical phenotype and genetic analysis of six Chinese patients affected with Acromicric dysplasia due to variants of FBN1 gene

To retrospectively analyze the clinical and genetic characteristics of six patients with Acromicric dysplasia due to variants of the FBN1 gene. Six patients who had visited the Affiliated Hospital of Qingdao University between February 2018 and October 2020 were selected as the study subjects. Clinical data of the patients were collected. High-throughput sequencing was carried out. And candidate variants were verified by Sanger sequencing. All of the six patients had presented with severe short stature (< 3s), brachydactyly, short and broad hands and feet. Other manifestations included joint stiffness, facial dysmorphism, delayed bone age, liver enlargement, coracoid femoral head, and lumbar lordosis. Genetic testing revealed that all had harbored heterozygous variants of the FBN1 gene. Patient 1 had harbored a c.5183C>T (p.A1728V) missense variant in exon 42, which had derived from his father (patient 2). Patient 3 had harbored a c.5284G>A (p.G1762S) missense variant in exon 43, which had derived from her mother (patient 4). Patient 5 had harbored a c.5156G>T (p.C1719F) missense variant in exon 42, which was de novo in origin. Patient 6 had harbored a c.5272G>T (p.D1758Y) missense variant in exon 43, which was also de novo in origin. The variants carried by patients 1, 3 and 6 were known to be pathogenic. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the FBN1: c.5156G>T was rated as a pathogenic variant (PS2+PM1+PM2_Supporting +PM5+PP3). All of the six patients had severe short stature and a variety of other clinical manifestations, which may be attributed to the variants of the FBN1 gene.

Ameliorative Effect of Coenzyme Q10 on Phenotypic Transformation in Human Smooth Muscle Cells with FBN1 Knockdown.

Mutations of the FBN1 gene lead to Marfan syndrome (MFS), which is an autosomal dominant connective tissue disorder featured by thoracic aortic aneurysm risk. There is currently no effective treatment for MFS. Here, we studied the role of mitochondrial dysfunction in the phenotypic transformation of human smooth muscle cells (SMCs) and whether a mitochondrial boosting strategy can be a potential treatment. We knocked down FBN1 in SMCs to create an MFS cell model and used rotenone to induce mitochondrial dysfunction. Furthermore, we incubated the shFBN1 SMCs with Coenzyme Q10 (CoQ10) to assess whether restoring mitochondrial function can reverse the phenotypic transformation. The results showed that shFBN1 SMCs had decreased TFAM (mitochondrial transcription factor A), mtDNA levels and mitochondrial mass, lost their contractile capacity and had increased synthetic phenotype markers. Inhibiting the mitochondrial function of SMCs can decrease the expression of contractile markers and increase the expression of synthetic genes. Imposing mitochondrial stress causes a double-hit effect on the TFAM level, oxidative phosphorylation and phenotypic transformation of FBN1-knockdown SMCs while restoring mitochondrial metabolism with CoQ10 can rapidly reverse the synthetic phenotype. Our results suggest that mitochondria function is a potential therapeutic target for the phenotypic transformation of SMCs in MFS.

Rehabilitation for Marfan Syndrome

Abstract: Marfan syndrome is a spectrum of disorders caused by a heritable genetic defect of connective tissue that has an autosomal dominant mode of transmission. The defect itself has been isolated to the FBN1 gene on chromosome 15, which codes for the connective tissue protein fibrillin. Abnormalities in this protein cause a myriad of distinct clinical problems, of which the musculoskeletal, cardiac, and ocular system problems predominate. The skeleton of patients with Marfan syndrome typically displays multiple deformities. Mitral valve prolapses that requires valve replacement can occur as well. Given the variable expressivity of Marfan Syndrome, no single sign is pathognomonic; the diagnosis is made on clinical grounds on the basis of typical abnormalities. We reported a boy, 12 years old, referred from surgeon with diagnosis pectus carinatum pro brace. Chest protusion appeared since age 6, getting bigger without any complaint but cosmetic. Other complaints on feet which looked flat, sometimes ankle sore after long distance running or futsal. He was the first child and no family history had a condition like him. His hobby was playing futsal, and daily activities were independent without assistive devices. General appearance and vital signs were normal, cardiorespiratory assessment was normal, BMI on percentile 10-25, arm span to height ratio 1.09, lens subluxation of left eye, lens dislocation of right eye, poor standing balance, inadequate toe off, thoracic hyperkyphotic, positive wrist sign, true leg length discrepancy of 1 cm (left&gt;right), bilateral ankle ROM limitation, rigid flat feet suspected bilateral vertical talus, left hallux valgus, Marfan syndrome score 9, and normal echocardiography. In this patient, we gave semi rigid thoraco-lumbo-sacral orthosis (TLSO) with 3 points pressure system and rigid bar on protution area (custom molded). resistance exercise (F: 3x/week, I: moderate fatigue, Borg scale 13-15/20, T: 8-15 reps/ set, 2-3 set/ session, T: major muscle group upper and lower extremities aerobic exercise (F: 3x/week, I: moderate to vigorous, borg scale 13-15/20, T: ≥60 min/session, @5-10 min warming up and cooling down (stretching), T: sport (swimming, running, cycling). The patient was referred to a surgeon for a brace. In conclusion, this case report highlights the multidisciplinary management of patients with Marfan syndrome. Keywords: Marfan syndrome; typical abnormalities; multiple deformities

Novel variant of FBN2 in a patient with congenital contractual arachnodactyly

Congenital contractual arachnodactyly (CCA) is a genetic connective tissue disorder that is characterized by arachnodactyly, kyphoscoliosis, marfanoid habitus, and crumpled ears. We report a case of a boy with suspected Marfan syndrome. Genetic analysis revealed c.3207_3217+9del in a heterozygote form of the fibrillin-2 (FBN2) gene. This patient was diagnosed with CCA based on his phenotype, and the pathogenicity of this variant was classified according to cDNA analysis and protein modeling.

Identification of two novel large deletions in FBN1 gene by next-generation sequencing and multiplex ligation-dependent probe amplification.

Mutations in fibrillin-1 (FBN1) are known to be associated with Marfan syndrome (MFS), an autosomal dominant connective tissue disorder. Most FBN1 mutations are missense or nonsense mutations. Traditional molecular genetic testing for the FBN1 gene, like Sanger sequencing, may miss disease-causing mutations in the gene's regulatory regions or non-coding sequences, as well as partial or complete gene deletions and duplications. Next-generation sequencing, multiplex ligation-dependent probe amplification and gap PCR were conducted on two MFS patients to screen for disease-causing mutations. We identified two large deletions in FBN1 from two MFS patients. One patient had a 0.23 Mb deletion (NC_000015.9:g.48550506_48779360del) including 5'UTR-exon6 of FBN1. The other patient harbored a 1416 bp deletion (NC_000015.9:g.48410869_48412284del) affecting the last exon, exon 66, of the FBN1 gene. Our results expanded the number of large FBN1 deletions and highlighted the importance of screening for large deletions in FBN1 in clinical genetic testing, especially for those with the classic MFS phenotype.

Research of miR-29a on TGF-β1/Smad3 pathway in pulmonary fibrosis induced by neodymium oxide

Objective: To exploring the regulatory effect of miR-29a on the transforming growth factor-β1 (TGF-β1) /Smad homolog 3 (Smad3) pathway during the process of rare earth neodymium oxide (Nd(2)O(3)) induced pulmonary fibrosis in mice. Methods: In March 2021, 72 SPF grade C57/BL6J male mice were selected and randomly divided into a control group, Nd(2)O(3) group, Nd(2)O(3)+miR-29a agomir group, and Nd(2)O(3)+NC agomir group, with 18 mice in each group. The Nd(2)O(3) group, Nd(2)O(3)+miR-29a agomir group, and Nd(2)O(3)+NC agomir group were treated with non exposed tracheal instillation, with a dust concentration of 250 mg/ml and a dust volume of 0.1 ml. The control group was given the same volume of physiological saline. After exposure to Nd(2)O(3), 0.1 ml (5 nmol) of miR-29a agomir was injected into the tail vein of mice in the Nd(2)O(3)+miR-29a agomir group every 3 days, while 0.1 ml of NC agomir was injected into the tail vein of mice in the Nd(2)O(3)+NC agomir group. On the 7 th, 14 th, and 28 th days after dust exposure, 6 mice were killed in each group, and the lung tissue of the mice was taken out. HE staining was used to observe the pathological status of the mouse lung tissue; ELISA method was used to detect the levels of TGF-β1 and connective tissue growth factor (CTGF) in lung tissue; Use qRT-PCR detection method to detect the expression level of TGF-β1 mRNA; Using immunofluorescence assay to detect the expression level of Smad3 in mouse lung tissue; Use bioinformatics websites such as TargetScan7 and miRDB to predict the target gene of miR-29a. When the metrological date were satisfied with normal distribution, Mean±SD was used for comparison between groups, t test was used for two indepent samples, and LSD method was used when the variance was homogeneity in pairwise comparison. Results: HE staining showed that the Nd(2)O(3) group of mice showed obvious infiltration of inflammatory cells and structural disorder of alveoli in the early stage of lung tissue. At 28 days, the collagen fibers in the mouse lung tissue increased and the lung tissue showed fibrotic honeycomb like changes. The degree of pulmonary fibrosis in the Nd(2)O(3)+miR-29a agomir group of mice was significantly reduced; The content of TGF-β1 and CTGF in the lung tissue of mice in the Nd(2)O(3)+miR-29a agomir group was lower than that in the Nd(2)O(3)+NC agomir group (P<0.05) ; The relative expression level of TGF-β1 in the lung tissue of mice in the Nd(2)O(3)+miR-29a agomir group was lower than that in the Nd(2)O(3)+NC agomir group (P<0.05) ; The expression level of Smad3 in the nucleus of the Nd(2)O(3)+miR-29a agomir group was lower than that of the Nd(2)O(3)+NC agomir group (P<0.05). The prediction results of bioinformatics websites have found 152 downstream target genes related to miR-29a, among which FBN1, MAP2K6, KPNB1, COL1A2, SNIP1, LAMC1, and SP1 genes may be related to the regulatory effect of miR-29a on TGF-β1/Smad3 signaling pathway. Conclusion: miR-29a may affect lung fibrosis induced by rare earth Nd(2)O(3) exposure in mice by regulating TGF-β1/Smad3 signaling pathway. Overexpression of miR-29a may inhibit TGF-β1/Smad3 signaling pathway and reduce the degree of pulmonary fibrosis in mice.

Three-dimensional co-culturing of stem cell-derived cardiomyocytes and cardiac fibroblasts reveals a role for both cell types in Marfan-related cardiomyopathy

Pathogenic variants in the FBN1 gene, which encodes the extracellular matrix protein fibrillin-1, cause Marfan syndrome (MFS), which affects multiple organ systems, including the cardiovascular system. Myocardial dysfunction has been observed in a subset of patients with MFS and in several MFS mouse models. However, there is limited understanding of the intrinsic consequences of FBN1 variants on cardiomyocytes (CMs). To elucidate the CM-specific contribution in Marfan's cardiomyopathy, cardiosphere cultures of CMs and cardiac fibroblasts (CFs) are used. CMs and CFs were derived by human induced pluripotent stem cell (iPSC) differentiation from MFS iPSCs with a pathogenic variant in FBN1 (c.3725G>A; p.Cys1242Tyr) and the corresponding CRISPR-corrected iPSC line (Cor).Cardiospheres containing MFS CMs show decreased FBN1, COL1A2 and GJA1 expression. MFS CMs cultured in cardiospheres have fewer binucleated CMs in comparison with Cor CMs. 13% of MFS CMs in cardiospheres are binucleated and 15% and 16% in cardiospheres that contain co-cultures with respectively MFS CFs and Cor CFs, compared to Cor CMs, that revealed up to 23% binucleation when co-cultured with CFs. The sarcomere length of CMs, as a marker of development, is significantly increased in MFS CMs interacting with Cor CF or MFS CF, as compared to monocultured MFS CMs. Nuclear blebbing was significantly more frequent in MFS CFs, which correlated with increased stiffness of the nuclear area compared to Cor CFs.Our cardiosphere model for Marfan-related cardiomyopathy identified a contribution of CFs in Marfan-related cardiomyopathy and suggests that abnormal early development of CMs may play a role in the disease mechanism.

The extracellular matrix glycoprotein fibrillin-1 in health and disease.

Fibrillin-1 (FBN1) is a large, cysteine-rich, calcium binding extracellular matrix glycoprotein encoded by FBN1 gene. It serves as a structural component of microfibrils and provides force-bearing mechanical support in elastic and nonelastic connective tissue. As such, mutations in the FBN1 gene can cause a wide variety of genetic diseases such as Marfan syndrome, an autosomal dominant disorder characterized by ocular, skeletal and cardiovascular abnormalities. FBN1 also interacts with numerous microfibril-associated proteins, growth factors and cell membrane receptors, thereby mediating a wide range of biological processes such as cell survival, proliferation, migration and differentiation. Dysregulation of FBN1 is involved in the pathogenesis of many human diseases, such as cancers, cardiovascular disorders and kidney diseases. Paradoxically, both depletion and overexpression of FBN1 upregulate the bioavailability and signal transduction of TGF-β via distinct mechanisms in different settings. In this review, we summarize the structure and expression of FBN1 and present our current understanding of the functional role of FBN1 in various human diseases. This knowledge will allow to develop better strategies for therapeutic intervention of FBN1 related diseases.

Overcoming challenges associated with identifying FBN1 deep intronic variants through whole-genome sequencing.

Marfan syndrome (MFS), caused by pathogenic variants of FBN1 (fibrillin-1), is a systemic connective tissue disorder with variable phenotypes and treatment responsiveness depending on the variant. However, a significant number of individuals with MFS remain genetically unexplained. In this study, we report novel pathogenic intronic variants in FBN1 in two unrelated families with MFS. We evaluated subjects with suspected MFS from two unrelated families using Sanger sequencing or multiplex ligation-dependent probe amplification of FBN1 and/or panel-based next-generation sequencing. As no pathogenic variants were identified, whole-genome sequencing was performed. Identified variants were analyzed by reverse transcription-PCR and targeted sequencing of FBN1 mRNA harvested from peripheral blood or skin fibroblasts obtained from affected probands. We found causative deep intronic variants, c.6163+1484A>T and c.5788+36C>A, in FBN1. The splicing analysis revealed an insertion of in-frame or out-of-frame intronic sequences of the FBN1 transcript predicted to alter function of calcium-binding epidermal growth factor protein domain. Family members carrying c.6163+1484A>T had high systemic scores including prominent skeletal features and aortic dissection with lesser aortic dilatation. Family members carrying c.5788+36C>A had more severe aortic root dilatation without aortic dissection. Both families had ectopia lentis. Variable penetrance of the phenotype and negative genetic testing in MFS families should raise the possibility of deep intronic FBN1 variants and the need for additional molecular studies. This study expands the mutation spectrum of FBN1 and points out the importance of intronic sequence analysis and the need for integrative functional studies in MFS diagnosis.

The Fbn1 gene variant governs passive ascending aortic mechanics in the mgΔlpn mouse model of Marfan syndrome when superimposed to perlecan haploinsufficiency.

Ascending thoracic aortic aneurysms arise from pathological tissue remodeling that leads to abnormal wall dilation and increases the risk of fatal dissection/rupture. Large variability in disease manifestations across family members who carry a causative genetic variant for thoracic aortic aneurysms suggests that genetic modifiers may exacerbate clinical outcomes. Decreased perlecan expression in the aorta of mgΔlpn mice with severe Marfan syndrome phenotype advocates for exploring perlecan-encoding Hspg2 as a candidate modifier gene. To determine the effect of concurrent Hspg2 and Fbn1 mutations on the progression of thoracic aortopathy, we characterized the microstructure and passive mechanical response of the ascending thoracic aorta in female mice of four genetic backgrounds: wild-type, heterozygous with a mutation in the Fbn1 gene (mgΔlpn), heterozygous with a mutation in the Hspg2 gene (Hspg2+/-), and double mutants carrying both the Fbn1 and Hspg2 variants (dMut). Elastic fiber fragmentation and medial disarray progress from the internal elastic lamina outward as the ascending thoracic aorta dilates in mgΔlpn and dMut mice. Concurrent increase in total collagen content relative to elastin reduces energy storage capacity and cyclic distensibility of aortic tissues from mice that carry the Fbn1 variant. Inherent circumferential tissue stiffening strongly correlates with the severity of aortic dilatation in mgΔlpn and dMut mice. Perlecan haploinsufficiency superimposed to the mgΔlpn mutation curbs the viability of dMut mice, increases the occurrence of aortic enlargement, and reduces the axial stretch in aortic tissues. Overall, our findings show that dMut mice are more vulnerable than mgΔlpn mice without an Hspg2 mutation, yet later endpoints and additional structural and functional readouts are needed to identify causative mechanisms.

Assessing the impact of storage conditions on RNA from human saliva and its application to the identification of mRNA biomarkers for asthma.

Introduction: Human saliva was used to develop non-invasive liquid biopsy biomarkers to establish saliva as an alternate to blood and plasma in translational research. The present study focused on understanding the impact of sample storage conditions on the extraction of RNA from saliva and the RNA yield, to be applied in clinical diagnosis. In this study, genes related to asthma were used to test the method developed. Methods: Salivary RNA was extracted from three subjects using the Qiazol® based method and quantified by both spectrophotometric (NanoDrop) and fluorometric (Qubit®) methods. RNA integrity was measured using a bioanalyzer. Quantitative PCR was used to monitor the impact of storage conditions on the expression of housekeeping genes: GAPDH and β-actin, and the asthma related genes: POSTN and FBN2. In addition, an independent cohort of 38 asthmatics and 10 healthy controls were used to validate the expression of POSTN and FBN2 as mRNA salivary biomarkers. Results: Approximately 2µg of total RNA was obtained from the saliva stored at 40°C without any preservative for 2weeks showing consistent gene expression with RNA stored at room temperature (RT) for 48h with RNAlater. Although saliva stored with RNAlater showed a substantial increase in the yield (110 to 234ng/μL), a similar Cq (15.6 ± 1.4) for the 18s rRNA gene from saliva without preservative showed that the RNA was stable enough. Gene expression analysis from the degraded RNA can be performed by designing the assay using a smaller fragment size spanning a single exon as described below in the case of the POSTN and FBN2 genes in the asthma cohort. Conclusion: This study showed that samples stored at room temperature up to a temperature of 40°C without any preservative for 2weeks yielded relatively stable RNA. The methodology developed can be employed to transport samples from the point of collection to the laboratory, under non-stringent storage conditions enabling the execution of gene expression studies in a cost effective and efficient manner.

Association of polymorphisms in FBN1, MYH11, and TGF-β signaling-related genes with susceptibility of sporadic thoracic aortic aneurysm and dissection in the Zhejiang Han population.

Sporadic thoracic aortic aneurysm and dissection (sTAAD) is a complicated vascular disease with a high mortality rate. And its genetic basis has not been fully explored. Here, 122 sTAAD patients and 98 healthy individuals were recruited, and 10 single nucleotide polymorphisms were selected and analyzed (FBN1 rs10519177, rs1036477, rs2118181, MYH11 rs115364997, rs117593370, TGFβ1 rs1800469, TGFβ2 rs900, TGFβR2 rs764522, rs1036095, and rs6785385). Moreover, multiple logistic regression analysis was used to evaluate gene-environment interactions. We identified that TGFβR2 rs1036095 dominant model CC + CG genotype (GT) (P = 0.004) may be a factor of increased risk of sTAAD, especially for women. FBN1 rs1036477 recessive model AA GT (P = 0.009) and FBN1 rs2118181 dominant model CC + CT GT (P = 0.009) were correlated to an increased death rate in sTAAD men patients. Gene-environment interactions indicated TGFβR2 rs1036095 dominant model (CC + CG)/GG to be a higher-risk factor for sTAAD (odds ratio = 3.255; 95% confidence interval: 1.324-8.000, P = 0.01). TGFβR2 rs1036095, FBN1 rs1036477, and FBN1 rs2118181 were identified as factors of increased risk of sTAAD. Gene-environment interactions were associated with the risk of sTAAD.

Quercetin antagonized advanced glycated end products induced apoptosis and functional inhibition of fibroblasts from the prolapsed uterosacral ligament.

The altered behaviors and functions of pelvic floor fibroblasts are pathophysiological changes of pelvic organ prolapse (POP). Our previous study showed that advanced glycated end products (AGEs) accumulated in the pelvic tissues of POP and induced fibroblast apoptosis. The study was designed to investigate whether quercetin antagonize AGEs-induced apoptosis and functional inhibition of fibroblasts. The uptake of 5-ethynyl-2'-deoxyuridine (EdU) was evaluated for cell proliferation. Flow cytometric analysis was applied for cell apoptosis. Intracellular reactive oxygen species (ROS) content was determined by the fluorescence of dichlorofluorescein (DCF). The contractility of fibroblasts was measured by collagen gel contraction assay. The expressions of extracellular matrix (ECM) related genes and the expression of miR-4429 and caspase-3 were quantified by qPCR. The expressions of phosphatase and tensin homolog (PTEN), phosphoinositide 3-kinase (PI3K), serine-threonine kinase (Akt), and phosphorylated Akt (p-Akt) were analyzed by Western Blot. The down-regulation of miR-4429 was achieved by cell transfection. Quercetin antagonized AGEs-induced apoptosis, proliferation inhibition, and ROS increase in fibroblasts. Quercetin did not alleviate AGEs-induced contractile impairment of fibroblasts. Quercetin reduced the gene expressions of lysyl oxidase like protein 1 (LOXL1)and matrix metallopeptidase 1 (MMP1), and increased the gene expressions of lysyl oxidase (LOX) and fibrillin 2 (FBN2) in fibroblasts. Quercetin reversed AGEs-induced upregulation of PTEN and downregulation of PI3K, P-Akt, and miR-4429 in fibroblasts. The inhibitory effect of quercetin on AGEs-induced fibroblast apoptosis was inhibited by downregulating the expression of miR-4429. In conclusion, quercetin antagonized AGEs-induced apoptosis and functional inhibition of fibroblasts from the prolapsed uterosacral ligament. And inhibiting AGEs-induced down-regulation of miR-4429/PTEN/PI3K/Akt pathway was the mechanism underlying the antagonistic effect of quercetin on AGEs-induced apoptosis.

Review of Asprosin as new Biomarker for diagnosis different Diseases

This study was designed to investigate the connections between (Inflammation, Cardiovascular diseases (CVDs),-diabetes mellitus,-Obesity,-polycystic ovary syndrome, thyroid and cancer )-and asprosin hormone. Asprosin is present in high amounts in a variety of diseases that are considerably manifested in several cases and illnesses Asprosin hormone is newly adipokine helps the liver produce glucose. White adipose tissue secretes the novel hormone asprosin, which stimulates the release of hepatic glucose, making protein a possible target for new treatments for obesity and type 2 diabetes mellitus. Exons (65 and 66) of the gene( Fibrillin 1 (FBN1)), which was recently shown to be a new hormone released by white adipose tissues, are the final two exons that code for asprosin. However, further research is needed to fully understand how asprosin affects pancreatic beta-cells, leading to pathologically elevated cellular dysfunction and inflammation. Asprosin hormone is raised in human with metabolic disease. The findings imply that asprosin hormone may be crucial for maintaining insulin and glucose homeostasis as well as acting as a risk factor for a number of diseases, including CVDs, obesity, T2DM, cancer, hypothyroidism, and PCOS. Depleting asprosin or attenuating its activity may potentially offer a novel therapeutic option for the treatment of T2DM and obesity.