COL1A1 Gene Research Articles

Pathological diagnosis of Alport syndrome.

Alport syndrome (AS) is a hereditary nephritis characterized by structural abnormalities in the glomerular basement membrane resulting from pathogenic variants in the COL4A3, COL4A4, and COL4A5 genes. Conventional pathological evaluations reveal nonspecific light microscopic changes and diagnostic clues can be obtained through electron microscopy. Type IV collagen staining elucidates distinct patterns based on AS inheritance, aiding in subtype classification. However, limitations arise, particularly in autosomal dominant cases. Genetic testing, particularly next-generation sequencing, gains prominence due to its ability to identify diverse mutations within COL4A3, COL4A4, and COL4A5.

Exploring the impact of diabetes on aging: insights from TERT and COL1A1 methylation.

Aging, a multifaceted biological process, leads to diminished physical performance, especially in older adults with diabetes, where a mismatch between biological and chronological age is noticeable. Numerous studies have demonstrated that diabetes accelerates aging at the cellular and organ levels. Notable aging markers are telomerase reverse transcriptase (TERT), related to telomere length, and type 1 chain collagen (COL1A1), a key component of skin collagen. Additionally, age-related methylation increases, as revealed through methylation analysis, augmenting aspects of aging. However, the detailed interplay between aging and diabetes, particularly regarding methylation, remains underexplored and warrants further study to elucidate the biological links between the two. In this study, we elucidate the modulatory influence of diabetes on the aging process, focusing specifically on the modifications in TERT in the kidney and COL1A1 in the skin using mice of Swiss Webster strain as the diabetes model. Specimens were categorized into three distinct chronological cohorts: chronologically young (16 weeks; n = 5), chronologically old (40 weeks; n = 5), and a periodically assessed group (16 weeks; n = 30), from which five mice were systematically sacrificed on a weekly basis. Our findings reveal a marked impact of diabetes on the methylation statuses of TERT and COL1A1, characterized by an elevation in methylation levels within the periodic group (1st-6th week) and a simultaneous, progressive attenuation in the expression of TERT and COL1A1 genes. The observed alterations in the methylation levels of TERT and COL1A1 propound the hypothesis that diabetes potentially expedites the aging process, concomitantly impinging on the production of TERT and COL1A, ostensibly through the mechanism of promoter gene hypermethylation.

A benign form of epidermolysis bullosa pruriginosa with a novel mutation in COL7A1 gene in a Polish family: a case series and literature review

A benign form of epidermolysis bullosa pruriginosa with a novel mutation in COL7A1 gene in a Polish family: a case series and literature review

PPARβ/δ attenuates hepatic fibrosis by reducing SMAD3 phosphorylation and p300 levels via AMPK in hepatic stellate cells

The role of peroxisome proliferator-activated receptor (PPAR)β/δ in hepatic fibrosis remains a subject of debate. Here, we examined the effects of a PPARβ/δ agonist on the pathogenesis of liver fibrosis and the activation of hepatic stellate cells (HSCs), the main effector cells in liver fibrosis, in response to the pro-fibrotic stimulus transforming growth factor-β (TGF-β). The PPARβ/δ agonist GW501516 completely prevented glucose intolerance and peripheral insulin resistance, blocked the accumulation of collagen in the liver, and attenuated the expression of inflammatory and fibrogenic genes in mice fed a choline-deficient high-fat diet (CD-HFD). The antifibrogenic effect of GW501516 observed in the livers CD-HFD-fed mice could occur through an action on HSCs since primary HSCs isolated from Ppard-/- mice showed increased mRNA levels of the profibrotic gene Col1a1. Moreover, PPARβ/δ activation abrogated TGF-β1-mediated cell migration (an indicator of cell activation) in LX-2 cells (immortalized activated human HSCs). Likewise, GW501516 attenuated the phosphorylation of the main downstream intracellular protein target of TGF-β1, suppressor of mothers against decapentaplegic (SMAD)3, as well as the levels of the SMAD3 co-activator p300 via the activation of AMP-activated protein kinase (AMPK) and the subsequent inhibition of extracellular signal-regulated kinase-1/2 (ERK1/2) in LX-2 cells. Overall, these findings uncover a new mechanism by which the activation of AMPK by a PPARβ/δ agonist reduces TGF-β1-mediated activation of HSCs and fibrosis via the reduction of both SMAD3 phosphorylation and p300 levels.

Genetic study of Alport syndrome in Tunisia.

Alport syndrome is a genetic disorder affecting the kidneys, ears, and eyes, causing chronic kidney disease, sensorineural hearing loss, and ocular abnormalities. It results from pathogenic variants in the COL4A3, COL4A4, or COL4A5 genes, with different inheritance patterns: X-linked from COL4A5 variants, autosomal recessive from homozygous variants in COL4A3 or COL4A4, digenic from variants in both COL4A3 and COL4A4, and autosomal dominant from heterozygous variants in COL4A3 or COL4A4. We analyzed 45 patients with Alport syndrome from 11 Tunisian families to determine their clinical and genetic characteristics. Clinical data were collected retrospectively, and whole-exome sequencing was conducted on one patient from each family. Sanger sequencing validated pathogenic variants, and cascade screening extended the analysis to 53 individuals. We identified nine likely pathogenic variants among 11 index cases: six novel and three known variations. Of these, five were in COL4A3, and four were in COL4A5, with variants including frameshift, nonsense, missense, and alternative splicing. Most variations affected the Gly-XY codon. Among the 45 clinically identified siblings, 30 tested positive for Alport syndrome. The cascade screening identified 3 additional affected individuals, 10 unaffected siblings, and 10 unaffected parents. The mode of inheritance was autosomal recessive in six families and X-linked in four families. This study is the first to screen the mutational spectrum of Alport syndrome in Tunisia. It reveals novel pathogenic variants and suggests that autosomal recessive inheritance may be more common in the Tunisian population than X-linked inheritance, contrary to existing literature.

ГЕНЕТИЧЕСКАЯ ХАРАКТЕРИСТИКА Х-СЦЕПЛЕННОГО СИНДРОМА АЛЬПОРТА У ДЕТЕЙ: ДАННЫЕ ОДНОЦЕНТРОВОГО КОГОРТНОГО ИССЛЕДОВАНИЯ

X-linked Alport syndrome (XLAS) is a monogenic disease characterized by the progressive nephropathy development, sensorineural hearing loss and the lens and retina pathology. The clinical manifestations of the syndrome and the renal prognosis of patients are determined by the nature of the gene COL4A5 mutation. The range of COL4A5 genetic variants is different among populations. Information about the XLAS genetic structure in Russian pediatric cohort is insufficient. The purpose of this research was to determine the features of the spectrum of the gene COL4A5 genetic variants in children with XLAS. Materials and methods used: a single-center retrospective cohort study included children aged 2 to 17 y/o with genetically confirmed XLAS. Descriptions of variants in gene COL4A5 were performed using genome build GRCh37/hg19 in accordance with the reference sequence GRCh37/hg19 (Reference Sequence, HGVS) and the American College of Medical Genetics and Genomics (ACMG), AMP Clinical Practice Guidelines. Results: analysis of data from 174 probands from unrelated families showed that 108 (62%) children had missense variants in gene COL4A5 (62% v. 38%, missense v. non-missense variants, respectively, p=0.028), 24 (13.8%) had mutations leading to impaired RNA splicing, 17 (9.8%) had frameshift mutations, 14 (8%) had gene deletions and 10 (5.7%) had nonsense mutations. Missense variants were predominantly localized in the collagen domain compared to the non-collagen domain (n=102, 94.4%, p<0.001), in exons 18 to 41 (n=94; 94.8%) and were represented by glycine substitutions (n=90, 83.3%). Two common variants were identified in the cohort: NM_033380.3(COL4A5):c.1871G>A (p.Gly624Asp) in 28 (26%) and NM_033380.3(COL4A5):c.3319G>A (p.Gly1107Arg) in 4 (3.7%). Conclusion: the structure of COL4A5 genetic variants in the studied cohort was comparable with the current Worldwide data, such as two thirds of the examined had missense variants and ca. one-fifth had genetic variants leading to the protein synthesis absence. Two common missense variants in gene COL4A5 were identified, including the common variant NM_033380.3(COL4A5):c.1871G>A (p.Gly624Asp) that is of frequent occurrence in the European population.

СПЕКТР КЛИНИЧЕСКИХ ПРОЯВЛЕНИЙ Х-СЦЕПЛЕННОГО СИНДРОМА АЛЬПОРТА У ДЕВОЧЕК: ОДНОЦЕНТРОЕ КОГОРТНОЕ ИССЛЕДОВАНИЕ

X-linked Alport syndrome (XLAS) is an inherited disorder caused by genetic variants in gene COL4A5. The frequency and the severity of clinical manifestations as well as the risk of glomerulopathy progression are variable in XLAS in females, and the disease course features have not been sufficiently studied as yet. Since patient management tactics is determined by the disease course nature, studying the spectrum of XLAS clinical manifestations and prognosis in girls remains relevant. The purpose of this research was to determine the spectrum and the features of clinical manifestations of XLAS in girls. Materials and methods used: a single-center cohort prospective study was carried out by the Authors that included 74 girls aged 2 to 17 y/o with genetically proven XLAS diagnosis. Authors have analyzed the patients’ medical records identifying sensorineural hearing loss (SNHL), arterial hypertension (AH; blood pressure (BP) over 95% than at the patient’s age/height), albuminuria (Alb; norm<30 mg/mmol of creatinine), proteinuria (Pr; norm<100 mg/sq m/day) - with its degree, decrease in estimated glomerular filtration rate (eGFR, ml/min/1.73 sq m; norm≥90 ml/min/1.73 sq m) and angiotensin-converting enzyme inhibitors (ACEIs) therapy data. Results: all patients had hematuria with episodical macrohematuria in 27% of cases, proteinuria in 40%, eGFR decrease in 15%, SNHL in 8% and peripheral retinopathy in 7%. Girls with missense v. those with non-missense variants of COL4A5 more often had macrohematuria (0.15 v. 0.05; p=0.015) and albuminuria (1 v. 0.5; p<0.001) whilst no statistically significant difference was showed in proteinuria frequency and age of onset (0.48 v. 0.5 and 6.5 [3; 11] v. 5 [5; 8] y/o), eGFR decrease (0.15 v. 0.15; 12.4±2.6 v. 13.2 ±2.8 y/o), SNHL (0.07 v. 0.1; 13±2.8 v. 14.4±3.1 y/o) and retinopathy (0.04 v. 0.15; 14.3±3.5 v. 12.6±2.9 y/o). ACEIs therapy did not show any statistically significant effect on the cumulative proportion of patients with both proteinuria and eGFR decrease (log-rank test=1.25, p=0.213 and log-rank test=0.66, p=0.512, respectively). Conclusion: the results obtained demonstrate the need for a dynamic follow-up of girls with XLAS with the purpose of earliest possible detection of proteinuria and timely prescribing with nephroprotective therapy as well as hearing loss diagnosing and timely audiological correction.

Unraveling the molecular pathogenesis of Type 2 Diabetes and its impact on female infertility: A bioinformatics and systems biology approach

Type 2 diabetes mellitus (T2D) has been linked with female infertility (FI). Nevertheless, our understanding of the molecular hallmarks and underlying mechanisms remains elusive. This research article aimed to find the hub genes, pathways, transcription factors, and miRNA involved. For this study, softwares like cytoscape, string, Enrichr, FFL loop, etc., were utilized. This research article employed differentially expressed genes (DEGs) to identify multiple biological targets to understand the association between T2D and female infertility (FI). Between T2D and FI, we found 3869 differentially expressed genes. We have also analyzed different pathways like thyroid hormone signaling pathways, AGE-RAGE signaling pathways in diabetic complications and ubiquitin-mediated proteolysis through pathway analysis. Moreover, hub genes MED17, PRKCG, THRA, FOXO1, NCOA2, PLCG2, COL1A1, CXCL8, PRPF19, ANAPC5, UBE2I, XIAP and KEAP1 have been identified. Additionally, these hub genes were subjected to identify the miRNA-mRNA regulation network specific to T2D-associated female infertility. In the FFL study (Feed Forward Loop), transcription factor (SP1, NFKB1, RELA and FOX01), miRNA (has-mir-7-5p, has-let-7a-5p, hsa-mir-16-5p, hsa-mir-155-5p, has-mir-122-5p, has-let-7b-5p, has-mir-124-3p, has-mir-34a-5p, has-mir-130a-3p, has-let-7i-5p, and hsa-mir-27a-3p) and six genes (XIAP, THRA, NCOA2, MED17, FOXO1, and COL1A1) among the thirteen key genes were recognized as regulator and inhibitor. Our analysis reveals that these genes can serve as a significant biomarker for female infertility linked with Type 2 Diabetes, through the prioritization of candidate genes. This study gives us insight into the molecular and cellular mechanism of T2D-associated FI. This finding helps in developing novel therapeutic approaches and will improve efficacy and reduce side effects of the treatment. This research requires further experimental investigation of the principal targets.

Phenotype-genotype spectrum of a cohort of congenital muscular dystrophies: a single-centre experience from India.

Congenital Muscular Dystrophies (CMD) are phenotypically and genotypically heterogenous disorders with a prevalence of 0.68 to 2.5/100,000, contributing to significant morbidity and mortality. We aimed to study the phenotype-genotype spectrum of genetically confirmed cases of CMD. This was retrospective & descriptive study done at a quaternary care referral centre in south India. Genetically confirmed cases of CMDs seen between 2010 to 2020 were recruited. Detailed clinical history, including pedigree, MRI brain/muscle, next generation sequencing results of 61 CMD cases were collected. Collagen VI-related dystrophy (COL6-RD) (36%) was the most common subtype with variants frequently seen in COL6A1 gene. Other CMDs identified were LAMA2-RD (26%), alpha-dystroglycan-RD (19%), LMNA-RD (8%), CHKB-RD (7%) and SEPN1-RD (3%). Similar to previous cohorts, overall, missense variants were common in COL-6 RD. Variants in triple helical domain (THD) of COL6-RD were seen in 11/22 patients, 5 of whom were ambulatory contrary to previous literature citing severe disease with these variants. However, our follow-up period was shorter. In the LAMA2-RD, 2/16 patients were ambulatory & all 16 carried truncating variants. Among dystroglycanopathies, FKRP-RD was the commonest. Milder phenotype of FKRP- RD was observed with variant c.1343C > T, which was also a recurrent variant in our cohort. p.Arg249Trp variant in LMNA-CMD associated with early loss of ambulation was also identified in 1/5 of our patients who expired at age 2.8years. The current retrospective series provides detailed clinical features and mutation patterns of genetically confirmed cases of CMD from a single center in India.

Abstract Mo137: Modulation of the Inflammatory and Fibrotic Effects of Angiotensin on Cardiomyocytes through YAP-mediated Transcription.

Introduction: Signaling through the transcriptional co-activator Yes-associated protein (YAP) has been shown to protect the myocardium against ischemic or mechanical stress. Research Question: In light of the critical role of inflammation on adverse cardiac responses we examined the possibility that YAP regulates inflammatory responses to Angiotensin II (AngII)-mediated stress. Approach: Cardiomyocyte specific YAP-KO mice were generated, implanted with AngII minipumps, infused with AngII (1.5 mg/kg/min) or vehicle for periods of 3 hrs to 3 days and hearts collected for analysis. Results: YAP deletion markedly enhanced AngII-induced mRNA expression of pro-inflammatory cytokines and chemokines (e.g. CCL2, CXCL2, IL-6) at 3 or 24 hrs in the cardiomyocyte, but not non-myocyte cell fraction. Expression of mRNA for the hypertrophic genes ANP and MHC-β, in contrast, was decreased in YAP KO mice. After 3 days of AngII infusion there was enhanced mRNA for pro-fibrotic genes (Col1a1, Col3a1 and Periostin) and increased staining for COL1A1 and F4/80, indicative of increased fibrosis and inflammatory cell recruitment in the absence of YAP signaling. Single cell RNA sequencing revealed specific subsets of genes that were upregulated in the cardiomyocyte subcluster from YAP KO mice. These included pro-inflammatory cytokines, cJun family genes, TLR4 and, surprisingly, CaMKIId. Elevated activation of CaMKIIδ in response to AngII in YAP KO hearts was confirmed by increased phosphorylation of phospholamban. Cardiomyocytes expressing siYAP also showed enhanced expression of TLR4 and CaMKIIδ. Conclusion: Upregulated expression of cJun, TLR4 and CaMKII occurs in the absence of YAP and this conspires to create a greatly enhanced inflammatory milieu which fuels adverse responses to external insults. YAP activation serves to suppress these responses and thus temper development of maladaptive inflammation.

Whole exome sequencing in relapsed or refractory childhood cancer: case series.

The prognosis for relapsed or refractory childhood cancer is approximately 20%. Genetic alterations are one of the significant contributing factors to the prognosis of patients. To investigate the molecular profile of relapsed or refractory childhood cancers in Thai cases. The study design is a descriptive study of patients <18 years old, suspected or diagnosed of relapsed or refractory childhood cancer who underwent whole exome sequencing (WES). WES was successfully performed in both the tumor and the blood or saliva samples obtained from 4 unrelated patients. Six different variants were identified in the NCOR2, COL6A3, TP53, and SMAD4 genes. These alterations were found to be associated with tumor aggressiveness. This study is the first one to demonstrate genetic alterations by using WES in relapsed or refractory childhood cancer in Thai cases.

Apoptosis and Inflammation Involved with Fluoride-Induced Bone Injuries.

Excessive fluoride exposure induces skeletal fluorosis, but the specific mechanism responsible is still unclear. Therefore, this study aimed to identify the pathogenesis of fluoride-induced bone injuries. We systematically searched fluoride-induced bone injury-related genes from five databases. Then, these genes were subjected to enrichment analyses. A TF (transcription factor)-mRNA-miRNA network and protein-protein interaction (PPI) network were constructed using Cytoscape, and the Human Protein Atlas (HPA) database was used to screen the expression of key proteins. The candidate pharmacological targets were predicted using the Drug Signature Database. A total of 85 studies were included in this study, and 112 osteoblast-, 35 osteoclast-, and 41 chondrocyte-related differential expression genes (DEGs) were identified. Functional enrichment analyses showed that the Atf4, Bcl2, Col1a1, Fgf21, Fgfr1 and Il6 genes were significantly enriched in the PI3K-Akt signaling pathway of osteoblasts, Mmp9 and Mmp13 genes were enriched in the IL-17 signaling pathway of osteoclasts, and Bmp2 and Bmp7 genes were enriched in the TGF-beta signaling pathway of chondrocytes. With the use of the TF-mRNA-miRNA network, the Col1a1, Bcl2, Fgfr1, Mmp9, Mmp13, Bmp2, and Bmp7 genes were identified as the key regulatory factors. Selenium methyl cysteine, CGS-27023A, and calcium phosphate were predicted to be the potential drugs for skeletal fluorosis. These results suggested that the PI3K-Akt signaling pathway being involved in the apoptosis of osteoblasts, with the IL-17 and the TGF-beta signaling pathways being involved in the inflammation of osteoclasts and chondrocytes in fluoride-induced bone injuries.

Development of polyvinyl alcohol nanofiber scaffolds loaded with flaxseed extract for bone regeneration: phytochemicals, cell proliferation, adhesion, and osteogenic gene expression.

Introduction: Bone tissue engineering seeks innovative materials that support cell growth and regeneration. Electrospun nanofibers, with their high surface area and tunable properties, serve as promising scaffolds. This study explores the incorporation of flaxseed extract, rich in polyphenolic compounds, into polyvinyl alcohol (PVA) nanofibers to improve their application in bone tissue engineering. Methods: High-performance liquid chromatography (HPLC) identified ten key compounds in flaxseed extract, including polyphenolic acids and flavonoids. PVA nanofibers were fabricated with 30 wt.% flaxseed extract (P70/E30) via electrospinning. We optimized characteristics like diameter, hydrophilicity, swelling behavior, and hydrolytic degradation. MG-63 osteoblast cultures were used to assess scaffold efficacy through cell adhesion, proliferation, viability (MTT assay), and differentiation. RT-qPCR measured expression of osteogenic genes RUNX2, COL1A1, and OCN. Results: Flaxseed extract increased nanofiber diameter from 252nm (pure PVA) to 435nm (P70/E30). P70/E30 nanofibers showed higher cell viability (102.6% vs. 74.5% for pure PVA), although adhesion decreased (151 vs. 206 cells/section). Notably, P70/E30 enhanced osteoblast differentiation, significantly upregulating RUNX2, COL1A1, and OCN genes. Discussion: Flaxseed extract incorporation into PVA nanofibers enhances bone tissue engineering by boosting osteoblast proliferation and differentiation, despite reduced adhesion. These properties suggest P70/E30's potential for regenerative medicine, emphasizing scaffold optimization for biomedical applications.

COL5A1 overexpression correlates with poor prognosis in human cervical cancer.

Cervical cancer is the most prevalent malignant tumor in women. This study aims to detect collagen type V α1 chain (COL5A1) expression and its clinical relevance in the prognosis of patients with cervical cancer. Cervical cancer tissues and their paired adjacent normal tissues were prepared for tissue microarray. The expression of COL5A1 protein and the scores of the expression were evaluated by immunohistochemistry (IHC) staining. The prognostic value of COL5A1 was analyzed by R software version 4.2.1 with "survival, survminer, ggplot2" packages and Gene Expression Profiling Interactive Analysis (GEPIA). The cBioPortal database was utilized for the analysis of COL5A1 gene mutations. COL5A1 protein was overexpressed in human cervical cancer tissues compared to their paired adjacent normal tissues detected by IHC (P < 0.001). High expression of COL5A1 tends to be in elderly patients with cervical cancer. Survival analyses of clinical data of patients with cervical cancer showed that a high level of COL5A1 expression was significantly correlated with shorter overall survival (P = 0.031) and disease-free survival (P = 0.042) of patients. Further analyses of The Cancer Genome Atlas-Cervical Squamous Cell Carcinoma and the GEPIA survival datasets confirmed the association of high COL5A1 expression with poor overall survival of patients (P = 0.040 and P = 0.018, respectively). The analysis of genomic alterations of COL5A1 using the cBioPortal tool revealed that the COL5A1 gene was altered in 4% of cervical cancer patients and COL5A1 corresponding protein alterations with post-translational modifications were hydroxylation. COL5A1 is a tissue biomarker correlated with the poor prognosis of patients with cervical cancer, which may lead to a new clinical application.

Endometriotic tissue fragments are viable after cryopreservation in an ex vivo tissue model recapitulating the fibrotic microenvironment.

Is it possible to establish an ex vivo endometriosis model using cryopreserved endometriotic tissue fragments? Cryopreserved endometriotic tissue fragments remain viable after thawing and during at least 3days of culture and can therefore be used to establish an ex vivo endometriosis model to efficiently test potential therapeutic agents. Endometriosis is the most prevalent benign gynecologic disease with an enormous societal burden; however, curative therapies are still lacking. To efficiently test potential new therapies, an ex vivo model based on previously cryopreserved endometriotic tissue that recapitulates the different endometriosis subtypes and their microenvironment is highly desirable. Endometriotic tissue fragments of three different subtypes were obtained from 28 patients by surgical resection. After cryopreservation and thawing, viability and metabolic activity of these tissue fragments were assessed. Viability was compared with fresh fragments from 11 patients directly after surgical removal. Experimental intervention studies were performed in cryopreserved and thawed tissue fragments from two patients to confirm the usability of these tissues for ex vivo intervention studies. Endometriotic tissue fragments (n = 45) were cryopreserved according to three different protocols. After thawing, fragments were cultured for 24 h. A resazurin-based assay was performed to assess the metabolic activity of the tissue fragments. In addition, cell type-specific viability was analyzed by VivaFix, Hoechst 33342, and α-smooth muscle actin immunofluorescence staining and confocal microscopy. The presence of endometriosis was histologically confirmed based on hematoxylin-eosin staining. Cryopreserved and thawed tissue fragments were treated for 72 h with pirfenidone or metformin and COL1A1 and CEMIP gene expressions were assessed using RT-PCR and RT-qPCR, either in the whole tissue fragments or in myofibroblasts isolated by laser capture microdissection. Metabolic activity of endometriotic tissue fragments obtained from peritoneal (PER), ovarian (OMA), and deep (DE) endometriotic lesions was well preserved after cryopreservation in a dimethyl sulfoxide-based medium and was comparable with fresh tissue fragments. Relative metabolic activity compared to fresh tissue was 70% (CI: 92-47%) in PER, 43% (CI: 53-15%) in OMA and 94% (CI: 186-3%) in DE lesions. In fragments from PE lesions 92% (CI: 87-96%), from OMA lesions 95% (CI: 91-98%), and from DE lesions 88% (CI: 78-98%) of cells were viable after cryopreservation and thawing followed by a 24-h culture period. Differences in gene expression of fibrotic markers COL1A1 and CEMIP after 72-h treatment with pirfenidone or metformin could be detected in whole tissue fragments and in isolated myofibroblasts, indicating that cryopreserved and thawed endometriotic tissue fragments are suitable for testing anti-fibrotic interventions. N/A. Viability and metabolic activity of the endometriotic tissue fragments may have been partially compromised by damage sustained during the surgical procedure, contributing to inter-sample variance. The storage of viable endometriotic tissue fragments for later usage in an ex vivo model creates the possibility to efficiently test potential new therapeutic strategies and facilitates the exchange of viable endometriotic tissue between different research laboratories. This study was not financially supported by external funding. The authors declare no competing interest. N/A.

Allele-specific CRISPR-Cas9 editing inactivates a single nucleotide variant associated with collagen VI muscular dystrophy

The application of allele-specific gene editing tools can expand the therapeutic options for dominant genetic conditions, either via gene correction or via allelic gene inactivation in situations where haploinsufficiency is tolerated. Here, we used allele-targeted CRISPR/Cas9 guide RNAs (gRNAs) to introduce inactivating frameshifting indels at a single nucleotide variant in the COL6A1 gene (c.868G>A; G290R), a variant that acts as dominant negative and that is associated with a severe form of congenital muscular dystrophy. We expressed spCas9 along with allele-targeted gRNAs, without providing a repair template, in primary fibroblasts derived from four patients and one control subject. Amplicon deep-sequencing for two gRNAs tested showed that single nucleotide deletions accounted for the majority of indels introduced. While activity of the two gRNAs was greater at the G290R allele, both gRNAs were also active at the wild-type allele. To enhance allele-selectivity, we introduced deliberate additional mismatches to one gRNA. One of these optimized gRNAs showed minimal activity at the WT allele, while generating productive edits and improving collagen VI matrix in cultured patient fibroblasts. This study strengthens the potential of gene editing to treat dominant-negative disorders, but also underscores the challenges in achieving allele selectivity with gRNAs.

Setrusumab for the treatment of osteogenesis imperfecta: 12-month results from the phase 2b asteroid study.

Osteogenesis imperfecta (OI) is a rare genetic disorder commonly caused by variants of the type I collagen genes COL1A1 and COL1A2. OI is associated with increased bone fragility, bone deformities, bone pain, and reduced growth. Setrusumab, a neutralizing antibody to sclerostin, increased areal bone mineral density (aBMD) in a 21-week phase 2a dose escalation study. The phase 2b Asteroid (NCT03118570) study evaluated the efficacy and safety of setrusumab in adults. Adults with a clinical diagnosis of OI type I, III, or IV, a pathogenic variant in COL1A1/A2, and a recent fragility fracture were randomized 1:1:1:1 to receive 2, 8, or 20mg/kg setrusumab doses or placebo by monthly intravenous infusion during a 12-mo treatment period. Participants initially randomized to the placebo group were subsequently reassigned to receive setrusumab 20mg/kg open label. Therefore, only results from the 2, 8, and 20mg/kg double-blind groups are presented herein. The primary endpoint of Asteroid was change in distal radial trabecular volumetric bone mineral density (vBMD) from baseline at month 12, supported by changes in high-resolution peripheral quantitative computed tomography micro-finite element (microFE)-derived bone strength. A total of 110 adults were enrolled with similar baseline characteristics across treatment groups. At 12mo, there was a significant increase in mean (SE) failure load in the 20mg/kg group (3.17% [1.26%]) and stiffness in the 8 (3.06% [1.70%]) and 20mg/kg (3.19% [1.29%]) groups from baseline. There were no changes in radial trabecula vBMD (p>05). Gains in failure load and stiffness were similar across OI types. There were no significant differences in annualized fracture rates between doses. Two adults in the 20mg/kg group experienced related serious adverse reactions. Asteroid demonstrated a beneficial effect of setrusumab on estimates of bone strength across the different types of OI and provides the basis for additional phase 3 evaluation.

Identification and functional characteristics of a novel splicing heterozygote variant of COL2A1 associated with Stickler syndrome type I.

Stickler syndrome type I (STL1) is an autosomal dominant disorder characterized by ocular, auditory, orofacial, and skeletal anomalies. The main causes of STL1 are variants in the COL2A1 gene, which encodes a type II collagen precursor protein. The specific focus of this study was on a newborn from China diagnosed with STL1, with the aim of providing novel insights into the effects of a newly identified intronic variant in the COL2A1 gene on pre-mRNA splicing. Trio whole exome sequencing was used to identify the causative variant in the family. The identified variant was validated using Sanger sequencing. Bioinformatics programs were used to predict the pathogenicity of the candidate variant. Additionally, an in vitro minigene assay was used to investigate the effects of the identified variant on RNA splicing. The proband with STL1 had a novel heterozygous splicing variant in the intron nine acceptor donor site of COL2A1 (c.655-2A>G). This splice junction variant resulted in aberrant COL2A1 mRNA splicing, leading to the skipping of exon 10 and the production of a shorter protein that may lack the last 18 native amino acids. The c.655-2A>G variant in the COL2A1 gene leads to STL1 through abnormal splicing. By expanding the spectrum of variants in the COL2A1 gene, this finding improves the clinical understanding of STL1 and provides guidance for early diagnosis and disease counseling.

Injectable hydrogel scaffold incorporating microspheres containing cobalt-doped bioactive glass for bone healing.

Injectable in situ-forming scaffolds that induce both angiogenesis and osteogenesis have been proven to be promising for bone healing applications. Here, we report the synthesis of an injectable hydrogel containing cobalt-doped bioactive glass (BG)-loaded microspheres. Silk fibroin (SF)/gelatin microspheres containing BG particles were fabricated through microfluidics. The microspheres were mixed in an injectable alginate solution, which formed an in situ hydrogel by adding CaCl2. The hydrogel was evaluated for its physicochemical properties, in vitro interactions with osteoblast-like and endothelial cells, and bone healing potential in a rat model of calvarial defect. The microspheres were well-dispersed in the hydrogel and formed pores of >100 μm. The hydrogel displayed shear-thinning behavior and modulated the cobalt release so that the optimal cobalt concentration for angiogenic stimulation, cell proliferation, and deposition of mineralized matrix was only achieved by the scaffold that contained BG doped with 5% wt/wt cobalt (A-S-G5Co). In the scaffold containing higher cobalt content, a reduced biomimetic mineralization on the surface was observed. The gene expression study indicated an upregulation of the osteogenic genes of COL1A1, ALPL, OCN, and RUNX2 and angiogenic genes of HIF1A and VEGF at different time points in the cells cultured with the A-S-G5Co. Finally, the in vivo study demonstrated that A-S-G5Co significantly promoted both angiogenesis and osteogenesis and improved bone healing after 12 weeks of follow-up. These results show that incorporation of SF/gelatin microspheres containing cobalt-doped BG in an injectable in situ-forming scaffold can effectively enhance its bone healing potential through promotion of angiogenesis and osteogenesis.

Four novel mutations identified in the COL4A3, COL4A4 and COL4A5 genes in 10 families with Alport syndrome

BackgroundAlport syndrome (AS) is an inherited nephropathy caused by mutations in the type IV collagen genes. It is clinically characterized by damage to the eyes, ears and kidneys. Diagnosis of AS is hampered by its atypical clinical picture, particularly when the typical features, include persistent hematuria and microscopic changes in the glomerular basement membrane (GBM), are the only clinical manifestations in the patient.MethodsWe screened 10 families with suspected AS using whole exome sequencing (WES) and analyzed the harmfulness, conservation, and protein structure changes of mutated genes. In further, we performed in vitro functional analysis of two missense mutations in the COL4A5 gene (c.2359G > C, p.G787R and c.2605G > A, p.G869R).ResultsWe identified 11 pathogenic variants in the type IV collagen genes (COL4A3, COL4A4 and COL4A5). These pathogenic variants include eight missense mutations, two nonsense mutations and one frameshift mutation. Notably, Family 2 had digenic mutations in the COL4A3 (p.G1170A) and UMOD genes (p.M229K). Family 3 had a digenic missense mutation (p.G997E) in COL4A3 and a frameshift mutation (p.P502L fs*151) in COL4A4. To our knowledge, four of the 11 mutations are novel mutations. In addition, we found that COL4A5 mutation relation mRNA levels were significantly decreased in HEK 293 T cell compared to control, while the cellular localization remained the same.ConclusionsOur research expands the spectrum of COL4A3-5 pathogenic variants, which is helpful for clinical and scientific research.