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Osteogenesis imperfecta (OI) is a group of rare genetic disorders most commonly caused by reduced amount of biologically normal collagen type I, a structural component of the gastrointestinal tract and abdominal wall. The risk of gastrointestinal (GI) disease in individuals with OI is not well understood, despite GI complaints being frequently reported by the OI population. To investigate the risk of GI diseases in individuals with OI. A Danish nationwide register-based cohort study utilizing data from the Danish National Patient Register and the Danish National Prescription Register. All individuals registered with an OI diagnosis in Denmark from 1995 through 2018, along with a reference population matched 1:5 based on sex, birth year, and month. Sub-hazard ratios (SHR) for peptic ulcer disease, diverticular disease, gastrointestinal cancers, intestinal obstruction with ileus, constipation, abdominal wall hernia, and other reasons for abdominal discomfort. The study included 864 individuals with OI (472 women) and 4,276 in the reference population (2,332 women). The SHR was significantly increased for ulcer (3.28 [95% CI 2.21–4.28]), constipation (2.67 [1.91–3.74]), and hernia (among women: 1.85 [1.22–2.80]). Higher SHRs were also observed for inflammatory bowel disease, biliary and pancreatic diseases, appendicitis, and unspecified abdominal pain. SHRs were not statistically significantly increased for diverticular disease, gastrointestinal cancers, intestinal obstruction with ileus, kidney stones or hemorrhoid disease. Individuals with OI have a higher risk of peptic ulcer disease, constipation, hernia among women, inflammatory bowel diseases, biliary and pancreatic diseases, appendicitis, and unspecified abdominal pain, compared with the general population. [ABSTRACT FROM AUTHOR]

Osteogenesis imperfecta (OI) is a group of rare hereditary collagen disorders. Hearing loss (HL) is a known complication linked to changes in the bones of the middle ear seen in OI. We aimed to determine the prevalence, age at debut, incidence, and risk of HL, surgery on bones of the middle ear, and use of hearing aids. A Danish nationwide, register-based cohort study. Data were extracted from the Danish National Patient register. Anyone with an OI diagnosis between January 1st 1977 and December 31st 2018, matched 1:5 with a reference population (Ref.Pop) on birthyear and sex, were included. 864 persons (487 women) with OI were included in the study and 4276 (2330 women) in the Ref.Pop. The sub-hazard ratio (SHR) for any HL was 4.56 [95% CI 3.64–5.71], with a prevalence of 17.0% and 4.0% in the OI cohort and Ref.Pop. Median age at debut was 42 and 58 years, respectively. The risk of otosclerosis and/or surgery was higher in the OI cohort (SHR 22.51 [95% CI 12.62–40.14]), with a median age at debut of 43 and 32 years in the OI cohort and Ref.Pop, respectively. Hearing aid use was more frequent in the OI cohort (SHR 4.16 [95% CI 3.21–5.40]) than in the Ref.Pop. The median age at debut was 45 and 60 years in the OI cohort and Ref.Pop, respectively. Persons with OI have a higher risk and prevalence of HL, hearing aids, and surgery, debuting younger, and prevalence increases with age. [ABSTRACT FROM AUTHOR]

Using the method of dynamic light scattering, it was found that the rate of collagen cleavage under the influence of bacterial collagenase decreases by almost 4 times when protein molecules are doped with Cr3+ ions, and when the enzyme activator of Zn2+ ions is added, it increases by 1.3 times. Based on the experimental data, the reaction rate constants k1 were calculated. It was found that when collagen molecules are tanned with a chromium salt, it becomes more resistant to degradation in solutions containing zinc ions than in solutions with the addition of calcium ions, as we described in earlier works. [ABSTRACT FROM AUTHOR]

Hepatic fibrosis is the first stage of liver disease, and can progress to a chronic status, such as cirrhosis or hepatocellular carcinoma. Excessive production of extracellular matrix (ECM) components plays an important role in the development of fibrosis. Mechanistically, transforming growth factor beta (TGFβ)-induced phosphorylation of Smad is thought to be a key signaling pathway in the development of liver fibrosis. Although the natural isoquinoline alkaloid oxoglaucine (1,2,9,10-tetramethoxy-7H-dibenzo(de,g)quinolin-7-one) exerts numerous beneficial effects, including anti-cancer, anti-inflammatory, and anti-osteoarthritic effects in diverse cell types, the effects of oxoglaucine on liver fibrosis and fibrogenic gene expression have not been fully elucidated. The aim of this study is to evaluate the signaling pathway and antifibrotic activity of isoquinoline alkaloid oxoglaucine in TFGβ-induced hepatic fibrosis in vitro. Using Hepa1c1c7 cells and primary hepatocytes, we demonstrated that oxoglaucine treatment resulted in inhibition of the expression of fibrosis markers such as collagen, fibronectin, and alpha-SMA. Subsequent experiments showed that oxoglaucine suppressed TGFβ-induced phosphorylation of Smad2 and reactive oxygen species (ROS) generation, without altering cell proliferation. We further determined that the increase in Smad7 by oxoglaucine treatment is responsible for the inhibition of Smad2 phosphorylation and the anti-fibrogenic effects. These findings indicate that oxoglaucine plays a crucial role in suppression of fibrosis in hepatocytes, thereby making it a potential drug candidate for treatment of liver fibrosis. [ABSTRACT FROM AUTHOR]

The present study was conducted to examine the bioactive and wound healing properties of collagen hydrolysate derived from Piaractus brachypomus (pacu) fish skin waste. Collagen type I (P coll.) yielding 72.25% was isolated from skin waste by following acid-soluble collagen extraction method. Further, collagen was fragmented using bacterial collagenase and the processed collagen hydrolysate (peptides) was in the range of 10–15 kDa that was further purified using ion-exchange chromatography. The FTIR spectra of both P coll. and collagen hydrolysate (PSCH) were nearly similar showing that PSCH retained the structural and chemical composition similar to its parent molecule (P coll.). Solubility analysis revealed that PSCH has slightly better solubility compared to P coll. Similarly, scanning electron micrographs also exhibited more uniform and porous microstructure of PSCH compared to P coll. Further, PSCH was found to be efficient in peroxide quenching (64.5%) and radical scavenging activities (85.74%). MTT studies confirmed PSCH to be non-toxic displaying 84.68% cell viability at the highest concentration (3 mg/ml) and hemocompatibility test revealed PSCH to be non-hemolytic with minimal lysis of only 2.1% of human RBCs. In addition, PSCH also displayed a remarkable wound closure ability of more than 80% at 12 h and 100% within 24 h. Hence, these findings suggest that recycled PSCH has potent wound healing ability and can be produced economically on a large scale for possible biological applications in regenerative medicine. [ABSTRACT FROM AUTHOR]

Patients with Osteogenesis Imperfecta (OI) have varying degrees of bone fragility and increased fracture rates. There is a paucity of data related to complications to pregnancies in patients with OI and to their offspring. With this study we aim to evaluate the risk of complications to pregnancies, delivery, and offspring in pregnancies where the mother or father have OI. Nationwide, register-based, cohort study. Danish health register-based data. All pregnancies registered in the Danish health registers where one parent has OI and a reference population of all other pregnancies in the general population from 1997 to 2018. Descriptive epidemiology Pregnancy and delivery complications (e.g. prevalence of pre-eclampsia, eclampsia and perinatal haemorrhage), and complications in the offspring (e.g. prevalence of low birth weight, low Apgar Score, need of CPAP or NICU, prevalence of congenital malformations (using the EUROCAT classification), incidence of osteogenesis imperfecta, prevalence of birth related fractures and hospital contacts during the first year of life) from pregnancies with parental OI. We identified 433 OI related pregnancies among 134 mothers with OI and 73 fathers with OI. The rates of pregnancy and delivery complications were similar between the OI cohorts and the reference population. More (31 % vs 19 %) children were delivered by caesarean section in the OI cohort than in the reference population. Pregnancies, where one parent have OI, result in live births to term with very few complications. • Fear of complications to the mother and risk of complications to the outcome may be a barrier for some patients with OI. • In mothers with OI, most pregnancies are without complications and go full term and results in healthy children. • This is the first nationwide, register based, cohorts study evaluating pregnancy risk in patients with OI. [ABSTRACT FROM AUTHOR]

In this study, a comparative structural and bioactive analysis of collagen extracted from the skin of bony and cartilaginous fishes. The acid-soluble method was followed to extract the collagen from Hypophthalmichthys molitrix (silver carp) and Rhizoprionodon acutus (milk shark) followed by purification using Ion exchange chromatography. A higher yield of collagen was obtained from the skin of SCsk (69.45%) as compared to SHsk (55.29%). SDS PAGE displayed the characteristic α, β bands of the collagen type1. The native conformation and secondary structure stability of collagen were confirmed by FTIR, XRD and CD studies. The SEM micrographs exhibited the layered and fibrillar nature of the collagen from SHsk and SCsk, respectively. Relative solubility and thermal denaturation analysis showed SCsk to be more stable, but SHsk could withstand higher temperatures. 53.65% of antioxidant activity was observed in SCsk collagen as compared to SHsk (45.9%). Haemocompatibility, cell viability and adhesion results also displayed silvercarp skin to be a better source than Shark skin collagen. The results establish the potential of silver carp collagen as a biomaterial that can have many commercial applications in tissue engineering, cosmetics and food industries. [ABSTRACT FROM AUTHOR]

Objective: Bladder cancer is the 9th leading cause of human urologic malignancy and the 13th cause of death worldwide. Increased collagen cross-linking, NIDOGEN1 expression and consequently stiffness of extracellular matrix (ECM) may be responsible for the mechanotransduction and regulation of transcriptional co-activator with PDZ-binding motif (TAZ) and transforming growth factor β1 (TGF-β1) signaling pathways, resulting in progression of tumorigenesis. The present study aimed to assess whether type 1 collagen expression is associated with TAZ nuclear localization. Materials and Methods: In this case-control study, real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemical analysis were performed to evaluate the activation of the TAZ pathway in patients with bladder cancer (n=40) and healthy individuals (n=20). The ELISA method was also conducted to measure the serum concentrations of TGF-β1. Masson’s trichrome staining was carried out to histologically evaluate the density of type 1 collagen. Results: Our findings that the expression levels of COL1A1, COL1A2, NIDOGEN1, TAZ, and TGF-β1 genes were overexpressed in patients with bladder cancer, and their expression levels were positively associated with the grade of bladder cancer. The immunohistochemical analysis demonstrated that the nuclear localization of TAZ was markedly correlated with high-grade bladder cancer. We also found that TAZ nuclear localization was substantially higher in cancerous tissues as compared with normal bladder tissues. Masson's trichrome staining showed that the tissue density of type I collagen was considerably increased in patients with bladder cancer as compared with healthy subjects. Conclusion: According to our findings, it seems the alterations in the expression of type I collagen and NIDOGEN1, as well as TAZ nuclear localization influence the progression of bladder cancer. The significance of TGF-β1 and TAZ expression in tumorigenesis and progression to high-grade bladder cancer was also highlighted. However, a possible relationship between TGF-β1 expression and the Hippo pathway needs further investigations. [ABSTRACT FROM AUTHOR]

Background: Prolotherapy is a proliferation therapy as an alternative medicine. A combination of dextrose solution and lidocaine is usually used in prolotherapy. The concentrations of dextrose and lidocaine used in the clinical field are very high (dextrose 10%-25%, lidocaine 0.075%-1%). Several studies show about 1% dextrose and more than 0.2% lidocaine induced cell death in various cell types. We investigated the effects of low concentrations of dextrose and lidocaine in fibroblasts and suggest the optimal range of concentrations of dextrose and lidocaine in prolotherapy. Methods: Various concentrations of dextrose and lidocaine were treated in NIH-3T3. Viability was examined with trypan blue exclusion assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Migration assay was performed for measuring the motile activity. Extracellular signal-regulated kinase (Erk) activation and protein expression of collagen I and α-smooth muscle actin (α-SMA) were determined with western blot analysis. Results: The cell viability was decreased in concentrations of more than 5% dextrose and 0.1% lidocaine. However, in the concentrations 1% dextrose (D1) and 0.01% lidocaine (L0.01), fibroblasts proliferated mildly. The ability of migration in fibroblast was increased in the D1, L0.01, and D1 + L0.01 groups sequentially. D1 and L0.01 increased Erk activation and the expression of collagen I and α-SMA and D1 + L0.01 further increased. The inhibition of Erk activation suppressed fibroblast proliferation and the synthesis of collagen I. Conclusions: D1, L0.01, and the combination of D1 and L0.01 induced fibroblast proliferation and increased collagen I synthesis via Erk activation. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective study. Purpose: This study aimed to assess the effect of refilling with hydroxyapatite/collagen (HAp/Col) composite on an iliac crest defect after spinal fusion. Overview of Literature: The use of iliac crest bone graft has been the gold standard in spinal fusion for a long time because of its biological and non-immunologic properties. Few reports have addressed how bone defects recover after iliac crest bone harvest following spinal fusion. Methods: Cancellous bone was collected from the anterior iliac crest during lateral interbody fusion (LIF), and the bone void of the ilium was refilled with a porous HAp/Col composite. We assessed bone recovery using computed tomography (CT). From the 74 patients who underwent LIF between January 2015 and December 2016, we included 49 patients whose iliac crest could be evaluated using CT at 3 months and 1 year after the surgery. Results: Bone defects decreased in a time-dependent manner after the surgery. Cortical closure was observed in 28.5% of the cases 3 months after the surgery; at 1 year postoperatively, 95.9% of the patients had cortical closure. Complete repair of the cancellous bone was achieved in 57.1% of the patients at 3 months after the surgery and in 95.9% at 1 year after the surgery. There were no significant hematomas, infections, iliac crest fractures, or soft tissue herniation. Conclusions: Radiographic recovery of cortical and cancellous bone defects was achieved with high probability via refilling with HAp/Col composite over the 1-year period. [ABSTRACT FROM AUTHOR]

Bioactive glasses (BG) are known for their unique ability to bond to bone tissue. However, in critical situations, even the osteogenic properties of BG may be not sufficient to produce bone consolidation. The use of composite materials may constitute an optimized therapeutical intervention for bone stimulation. The aim of this study was to characterize BG/collagen/poly (d , l -lactic- co -glycolic) acid (BG/COL/PLGA) composites, in vitro biocompatibility and in vivo biological properties. MC3T3-E1 cells were evaluated by cell proliferation, ALP activity, cell adhesion and morphology. Qualitative histology and immunohistochemistry were performed in a calvarial bone defect model in rats. The in vitro study demonstrated, after 3 and 6 days of culture, a significant increase of proliferation was observed for BG/PLGA compared to BG/COL and BG/COL/PLGA. BG/COL/PLGA presented a higher value for ALP activity after 3 days of culture compared to BG/PLGA. For in vivo analysis, 6 weeks post-surgery, BG/PLGA showed a more mature neoformed bone tissue. As a conclusion, the in vitro and in vivo studies pointed out that BG/PLGA samples improved biological properties in calvarial bone defects, highlighting the potential of BG/PLGA composites to be used as a bone graft for bone regeneration applications. [ABSTRACT FROM AUTHOR]

Background: Orthodontics of the 21st century requires aesthetic, painless, predictable, and quick treatments. This demand for faster results generated orthodontic movement acceleration protocols (OMAPs); among other OMAPs we present low-level laser (LLL) as a candidate. Objective: To evaluate levels of interleukin (IL)-1, IL-10, and type 1 collagen in the periodontal ligament of first molars of rats subjected to orthodontic traction with and without LLL irradiation, compared with untreated controls (CO), and to evaluate whether the dose of LLL used in this work is eligible as an OMAP. Materials and methods: A total of 35 male Wistar rats were distributed into three groups: group 1 NI (nonirradiated) n = 15, group 2 IR (laser irradiated using 5 J, 177 J/cm2, and 100 mW applied in contact to the vestibular mesial, vestibular distal, and palatal faces of gum tissue around molar region for 50 sec each point, for 3 consecutive days, immediately 24 and 48 h after orthodontic device placement.) n = 15, and group 3 CO n = 5; groups 1 and 2 were subjected to orthodontic force and each group was divided into three subgroups that were sacrificed after 3, 5, and 7 days, IL-1/10 and COL-1 levels were analyzed. Results: In the IR group, levels of IL-1/10 and COL-1 showed peak anticipation after LLL irradiation compared with those in the NI and CO groups. Conclusions: These results can also infer that this dose of LLL can be used as an OMAP. [ABSTRACT FROM AUTHOR]

This impaired lung growth results in the lack of attainment of normal lung size and maximal lung function (Yang et al., [5]). Keywords: alveoli; bronchopulmonary dysplasia; collagen type 1; lung development EN alveoli bronchopulmonary dysplasia collagen type 1 lung development 247 248 2 01/17/23 20230115 NES 230115 Dimori et al. ([1]) present a comprehensive study of pulmonary changes in mouse models of osteogenesis imperfecta (OI). These findings support the concept that the genetic underpinnings of OI are independently associated with abnormal pulmonary development, which is important not only for understanding OI but also for our understanding of lung development. [Extracted from the article]

The two mesenchymal stem cell (MSC) populations that have gained most attention in relation to bone tissue engineering are adipose tissue (AT) MSCs and bone marrow (BM) MSCs. The purpose of this study was to investigate the ability of human BM-MSCs and AT-MSCs to survive, proliferate and deposit collagen type 1 when cultured on polycaprolactone nanofiber scaffolds and to ascertain the effect of medium composition on collagen type 1 formation and expression of osteogenic genes. The cells were seeded on polycaprolactone nanofiber scaffolds and cultured in three different types of media that differed by the presence of ascorbic acid, β-glycerophosphate and dexamethasone, that are typical components used for osteogenic differentiation of MSCs in vitro . In summary, AT-MSCs were proliferating significantly faster than BM-MSCs. AT-MSCs also showed better ability to deposit collagen type 1 and had a higher expression of early osteogenic markers, whereas BM-MSCs had higher expression of late osteogenic markers. This suggests that MSCs from diverse sources have different attributes and with respect to osteogenic differentiation, AT-MSCs are more immature compared to BM-MSCs. Collagen formation was depending on medium composition and the organization of collagen type 1 appeared to be influenced by the presence of dexamethasone. [ABSTRACT FROM AUTHOR]

Objective To explore the mechanism and effects of globular adiponectin (gAd) on atherosclerosis in rats with type 2 diabetes mellitus (T2DM). Methods Ninety male Sprague-Dawley rats were divided into control group (group N, n=24) and T2DM model group (n=66) according to the method of random number table. Similarly, 53 successful modeling diabetic rats were randomly divided into T2DM group (group D, n=26) and intervention group (group A, n=27). Rats in group A were administrated with gAd in dose of 10 μg·kg-1·d-1, and rats in the other two groups were administrated with saline respectively. At the end of 4, 8 and 12 weeks (w), serum biochemical indexes were tested in 8 rats collected randomly from each group, respectively. In the mean time, atherosclerotic changes of thoracic aorta were observed by HE staining, and the expressions of type 1 collagen (Col-1) were detected by immunohistochemistry. The protein and mRNA expressions of transforming growth factor β1 (TGF-β1), Smad3, Smad7 were detected by Western blotting and real time fluorescent quantitative polymerase chain reaction, respectively. Statistical analysis was performed by using one way analysis of variance and LSD-t test. Results In each period, compared with group N, in group D, atherosclerotic changes of thoracic aorta appeared, the lesions worsened gradually with staining time, and the expressions of TGF-β1, Smad3 and Col-1 increased significantly (12 w: 1.28±0.01 vs 0.99±0.02, 1.08±0.01 vs 0.84±0.01, 183.3±0.6 vs 200.7±2.1, t=25.108, 20.779, 15.011, all P< 0.05), while the expression of Smad7 decreased (12 w: 0.72 ± 0.02 vs 1.10 ± 0.02, t=30.018, P<0.05). Compared with group D, in group A, atherosclerotic lesions of thoracic aorta were slight, and the expressions of TGF-β1, Smad3 and Col-1 decreased significantly (12 w: 1.05±0.01, 0.81±0.02, 196.3±1.2, t=19.913, 23.377, 11.258, all P<0.05), while the expression of Smad7 increased (12 w: 0.99±0.01, t=21.404, P<0.05). With the extending of gAd intervention, the atherosclerotic lesions mitigated, the expressions of TGF-β1, Smad3 and Col-1 decreased, Smad7 increased significantly (all P<0.05). Conclusions Globular adiponectin may inhibit the TGF-β1/Smads pathway by up-regulating Smad7 or down-regulating TGF-β1 and Smad3, and exert anti-fibrosis action in vascular wall to protect T2DM rats from atherosclerosis. [ABSTRACT FROM AUTHOR]

Osteogenesis imperfecta (OI) is a genetically and clinically heterogeneous disorder caused by disruption of type I collagen synthesis. Previous Brazilian molecular OI studies have been restricted to case reports or small cohorts. The Brazilian OI Network (BOIN) is a multicenter study collecting clinical OI treatment data from five reference centers in three regions of Brazil. To describe the molecular analysis of a large cohort of OI registered at BOIN. Targeted next-generation sequencing (NGS) was performed at a centralized laboratory with the Ion Torrent platform, covering 99.6 % of the coding regions of 18 OI-associated genes. Clinical information was obtained from a clinical database. We included 156 subjects in the molecular analyses. Variants were detected in 121 subjects: 65 (53.7 %) in COL1A1 , 42 (34.7 %) in COL1A2 , 2 (1.7 %) in IFITM5 , one (0.8 %) in CRTAP , three (2.5 %) in P3H1 , two (1.7 %) in PPIB , four (3.3 %) FKBP10 , one (0.8 %) in SERPINH1 , and one (0.8 %) in TMEM38B. Ninety-one distinct variants were identified, of which 26 were novel. Of the 107 variants identified in COL1A1 and COL1A2 , 24.5 % cause mild OI, while the remaining 75.5 % cause moderate, severe, or lethal OI, of which 49.3 % are glycine to serine substitutions. A single variant in FKBP10 (c.179A>C; p.Gln60Pro) was found in three unrelated and non-consanguineous participants living in the same geographic area in Northeast Brazil, suggesting a possible founder effect. Consistent with the literature, 88.4 % of the subjects had a variant in the COL1A1 and COL1A2 genes, with 10 % inherited in an autosomal recessive manner. Notably, one variant in FKBP10 with a potential founder effect requires further investigation. Data from this large cohort improves our understanding of genotype-phenotype correlations for OI in Brazil. • This is the largest molecular analysis study of OI in Brazil. • The majority of cases a collagen I defect was found (88.4 %). • In 9.9 % an autosomal recessive gene play a role in OI. • A possible founder effect was identified in three cases with a variant in FKBP10. [ABSTRACT FROM AUTHOR]

Summary: Osteogenesis imperfecta (OI) is characterized by a high fracture rate and great heterogeneity. This cross-sectional study presents skeletal investigations and protein analyses in 85 adult OI patients. We find significant differences in bone mass, architecture, and fracture rate that correlate well with the underlying biochemical and molecular abnormalities. Introduction: OI is a hereditary disease characterized by compromised connective tissue predominantly caused by mutations in collagen type 1 (COL-1) encoding genes. Widespread symptoms reflect the ubiquity of COL-1 throughout the body. The purpose of this study was to improve our understanding of clinical manifestations by investigating anthropometry and skeletal phenotypes (DXA, HRpQCT) in an adult OI population and compare the findings to underlying COL-1 genotype and structure. Methods: The study comprised 85 OI patients aged 45 (19-78) years, Sillence type I ( n = 58), III ( n = 12), and IV ( n = 15). All patients underwent DXA, HRpQCT, spine X-ray, biochemical testing, and anthropometry. COL1A1 and COL1A2 were sequenced and 68 OI causing mutations identified (46 in COL1A1, 22 in COL1A2). Analysis of COL-1 structure (quantitative/qualitative defect) by SDS-PAGE was performed in a subset ( n = 67). Results: A qualitative collagen defect predisposed to a more severe phenotype with reduced aBMD, more fractures, and affected anthropometry compared to patients with a quantitative COL-1 defect ( p < 0.05). HRpQCT revealed significant differences between patients with OI type I and IV. Patients with type I had lower vBMD ( p < 0.005), thinner cortexes ( p < 0.001), and reduced trabecular number ( p < 0.005) compared to patients with type IV indicating that HRpQCT may distinguish type I from type IV better than DXA. Conclusion: The defective collagen in patients with OI has pronounced effects on the skeleton. The classical OI types based on the clinical classification show profound differences in bone mass and architecture and the differences correlate well with the underlying biochemical and molecular collagen abnormalities. [ABSTRACT FROM AUTHOR]

A great amount of effort has been made in order to reach a more precise understanding of the adhesion phenomenon that happens as a vital component of several biological systems. Therefore, a firm understanding of the important factors that influence this phenomenon is of special importance in triggering the adhesive characteristics of different biological, bio-inspired and synthetic materials in fields such as tissue engineering. In this study the adhesive characteristics of a multi-material system consisting of the frequently used synthetic material, graphene, in the form of armchair-configuration sheets, and an important biological filament which is type 1 Collagen consisting of 3 alpha helices, has been studied in detail. The main emphasis of this study is placed on understanding the effects of the roughness characteristics of the inorganic elements which are the graphene sheets on the overall adhesive features of the system which are quantified within the framework of two main criteria: adhesion energy and peeling force. At first, the methodology used in order to obtain graphene sheets with various roughness values is described in detail. The abovementioned criteria are then evaluated through Molecular Dynamics (MD) modeling of the system in the NAMD simulation software environment and various simulation scenarios are studied. [ABSTRACT FROM AUTHOR]

Scaffold design is an important aspect ofin vitromodel development. In this study, nanoscaffold surface modification, namely UV radiation and genipin cross-linking to immobilize collagen on the surface of electrospun poly (methyl methacrylate) (PMMA) nanofiber sheet was investigated. Samples were divided into four groups; PMMA nanofibers (PMMA), collagen-coated PMMA nanofibers (PMMACOL), genipin cross-linked collagen-coated PMMA nanofibers (PMMAGEN), and UV-irradiated collagen-coated PMMA nanofibers (PMMAUV). 6 h of UV radiation significantly reduced the hydrophobicity of PMMA nanofibers from (131.88° ± 1.33°) to (110.04° ± 0.27°) (p < 0.05). The amount of collagen immobilized was significantly higher in PMMAGEN group (239.36 ± 16.63 μg collagen/mg nanofibers) (p < 0.05) compared to the other groups. RECs on all scaffold expressed epithelial cell-specific markers (CK18 and CK14), mucin-producing cell marker (MUC5Ac) and were actively proliferating, based on the positive expression of Ki67. Total number of attached cells was significantly the highest in PMMAUV group on day 9 (6.44 × 104 ± 2.77 × 104 cells/cm2) and it has the highest proliferation rate from day 4 to 9 (0.005 ± 0.003 h−1) compared to the other groups. Even though PMMAGEN group showed the highest collagen adsorption, in terms of cells attachment and proliferation, PMMAUV group showed a better outcome compared to the other groups. Thus, PMMAUV scaffold is more suitable to be used in the construction ofin vitrorespiratory epithelial model. [ABSTRACT FROM AUTHOR]

Ginsenoside, one of the active compounds in Panax ginseng , inhibits tumor growth factor-beta 1 (TGF-β1) and reduces the level of collagen type 1. Ginsenoside Rb1 promotes burn wound healing. Our study evaluated the effects of ginsenoside Rb1 on hypertrophic scar remodeling. A total of 72 hypertrophic scars were generated on the ears of six New Zealand white rabbits. Treatment groups were administered with intradermal injections of ginsenoside Rb1 at various amounts (0.07 mg, 0.28 mg and 0.56 mg), and evaluated on postoperative Day 35. Scar elevation index was used as a quantitative measure, and picrosirius staining of histological sections was used to assess collagen arrangement. We determined relative mRNA expression of collagen type 1 as well as scar related factors; matrix metalloproteinase 2 (MMP2), tissue-inhibitor of metalloproteinase 1 (TIMP1), alpha-smooth muscle actin (α-SMA), and TGF-β1. Immunohistochemistry assays were performed additionally. Application of 0.56 mg of ginsenoside Rb1 resulted in significant decrement of scar elevation index, in comparison with control and lower dosage groups, furthermore achieved broader and randomly arranged collagen fibers resembling findings in normal dermis. Ginsenoside Rb1 concentration inversely correlated with the mRNA expression and immunohistochemical reactivity of scar related factors; MMP2, TIMP1, α-SMA, and TGF-β1. In addition, ginsenoside Rb1 suppressed collagen type 1 expression. Ginsenoside Rb1 is therapeutic in hypertrophic scar remodeling with the highest efficacy at 0.56 mg of dosage. Ginsenoside Rb1 demonstrated inhibitory effects on hypertrophic scar in quantitative and histologic analysis. Further research is needed to determine optimal ginsenoside Rb1 application and exposure conditions. [ABSTRACT FROM AUTHOR]

In our previous studies, we confirmed that low-level laser therapy (LLLT) with a 980-nm gallium-aluminum-arsenide diode laser was beneficial for the healing of the alveolar bone in rats with systemic disease. However, many factors can affect the biostimulatory effects of LLLT. Thus, we attempted to investigate the effects of irradiation time on the healing of extraction sockets by evaluating the expressions of genes and proteins related to bone healing. The left and right first maxillary molars of 24 rats were extracted. Rats were randomly divided into four groups in which extraction sockets were irradiated for 0, 1, 2, or 5 min each day for 3 or 7 days. Specimens containing the sockets were examined using quantitative real-time reverse transcription polymerase chain reaction and western blotting. LLLT increased the expressions of all tested genes, Runx2, collagen type 1, osteocalcin, platelet-derived growth factor-B, and vascular endothelial growth factor, in a time-dependent manner. The highest levels of gene expressions were in the 5-min group after 7 days. Five minutes of irradiation caused prominent increases of the expression of all tested proteins after both 3 and 7 days. The expression level of each protein in group 4 was higher by almost twofold compared with group 1 after 7 days. Laser irradiation for 5 min caused the highest expressions of genes and proteins related to bone healing. In conclusion, LLLT had positive effects on the early stages of bone healing of extraction sockets in rats, which were irradiation time-dependent. [ABSTRACT FROM AUTHOR]

Urokinase type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) have been proposed to play key roles in extracellular matrix (ECM) deposition in hypertrophic scars (HS). Here, we found that in HS fibroblasts (HFs) miR-181c and miR-10a were differentially-expressed and targeted uPA and PAI-1, respectively. The production of Type 1 collagen (Col1) was inhibited by miR-181c knockdown or miR-10a overexpression in HFs, and this resulted in increased levels of metalloproteinase 1 (MMP1). These results suggest that the miR-181c–uPA and miR-10a–PAI-1 regulatory pathways have an integral role in HS pathogenesis. [ABSTRACT FROM AUTHOR]

Aim To study how products released from different bacteria in a deep carious lesion affect the metabolic activity of odontoblast-like cells and their ability to produce the major organic component of dentine, collagen 1. Methodology MDPC-23 cells were exposed to supernatants from biofilm cultures of strains isolated from the deepest part of a carious lesion as well as from a clinical isolate of Enterococcus faecalis. Lipoteichoic acid ( LTA) and lipopolysaccharide ( LPS) were used for comparison. Cell activity was assessed using an methyl-thiazolyl-diphenyl tetrazolium bromide ( MTT) assay, and collagen 1 levels were determined by ELISA. Results The lesion microflora was dominated by Lactobacillus spp. Neither extracellular products from the isolates nor LPS affected the activity of the MDPC-23 cells, whereas extracellular products from E. faecalis and LTA significantly reduced total cell activity ( P < 0.01). Enterococcus faecalis had an inhibitory effect upon collagen 1 production by the cells, whereas no such effect or even a slight stimulatory effect was seen for the isolates from the deep carious lesion. Conclusions These studies indicate that culture supernatants from E. faecalis reduced the metabolic activity of odontoblast-like cells as shown using the MTT assay. No effect was seen for supernatants from biofilms of bacteria recovered from a deep carious lesion. Different bacteria varied in their effects upon collagen 1 production suggesting that the nature of the bacterial species in a carious lesion may have a direct influence upon the ability of the odontoblasts to produce tertiary dentine. [ABSTRACT FROM AUTHOR]

Background. Osteoporosis is the most common metabolic bone disorder of the elderly, affecting the normal bone turnover with an increased bone resorption and subsequent higher risk of fragility fractures. Collagen type 1 is the most represented protein in bone matrix. A genetic variation (Sp1) in intron 1 of COL1A1 gene has been associated to modulation of expression of the alpha 1 chain of collagen type 1 and it is considered a candidate polymorphism for predisposition to osteoporosis status and fragility fractures. Association studies, in ethnically different populations, are needed to strongly confirm the role of this polymorphism in bone metabolism. Materials and methods. We enrolled over 2,000 Italian individuals and studied their bone mineral density (BMD) and fractures in relation to age, sex and body mass index (BMI). Moreover, we analyzed the distribution of Sp1 polymorphism in these individuals and associated it to normal bone status, osteopenic condition or osteoporosis diagnosis, BMD and the presence of low-trauma fractures. Results. The most rare ss genotype showed a trend for osteoporosis diagnosis with respect to both normal and osteopenic status. The same genotype resulted to be associated to lower values of BMD both at spine and femur sites. No association was found with fractures. Discussion. In conclusion the presence of the homozygote ss genotype seemed to predispose to osteoporosis diagnosis and to be more frequent in subjects with lower spine and femur BMD values. [ABSTRACT FROM AUTHOR]

To investigate the effects of 17beta-estradiol (E2) on extracellular matrix (ECM) protein synthesis (collagen type I, fibronectin, and laminin) using cultures of normal and scleroderma (SSc) skin fibroblasts. Primary fibroblasts cultures, obtained from skin biopsies of six female voluntary subjects and three female SSc patients, were treated for 24 h with E2 (10−10M) alone or in combination with tamoxifene (TAM, 10−7M) as an estrogen receptor (ER) antagonist. ECM protein synthesis was analyzed by immunocytochemistry and Western blotting. E2 induced a significant increase of fibronectin, collagen type I, and laminin synthesis both in normal ( P < 0.01, P < 0.05, P < 0.01, respectively) and SSc fibroblasts ( P < 0.001, P < 0.05, P < 0.001, respectively) when compared to untreated fibroblasts. TAM induced a significant decrease of ECM protein synthesis when compared to E2-treated TAM-untreated fibroblasts. This study seems to support important modulatory effects of E2 in the fibrotic progression of the SSc process via ER interactions. [ABSTRACT FROM AUTHOR]

Autosomal recessive lethal and severe osteogenesis imperfecta (OI) is caused by the deficiency of cartilage-associated protein (CRTAP) and prolyl-3-hydroxylase 1 (P3H1) because of CRTAP and LEPRE1 mutations. We analyzed five families in which 10 individuals had a clinical diagnosis of lethal and severe OI with an overmodification of collagen type I on biochemical testing and without a mutation in the collagen type I genes. CRTAP mutations not described earlier were identified in the affected individuals. Although it seems that one important feature of autosomal recessive OI due to CRTAP mutations is the higher consistency of radiological features with OI type II-B/III, differentiation between autosomal dominant and autosomal recessive OI on the basis of clinical, radiological and biochemical investigations proves difficult in the affected individuals reported here. These observations confirm that once a clinical diagnosis of OI has been made in an affected individual, biochemical testing for overmodification of collagen type I should always be combined with molecular genetic analysis of the collagen type I genes. If no mutations in the collagen type I genes are found, additional molecular genetic analysis of the CRTAP and LEPRE1 genes should follow. This approach will allow proper identification of the genetic cause of lethal or severe OI, which is important in providing prenatal diagnosis, preimplantation genetic diagnosis and estimating recurrence risk. [ABSTRACT FROM AUTHOR]

Because of its mechanical function, skeletal muscle is heavily influenced by the composition of its extracellular matrix (ECM). Fibrosis generated by chronic damage, such as occurs in muscular dystrophies, is thus particularly disastrous in this tissue. Here, we examined the interrelationship between the muscle satellite cell and the production of collagen type I, a major component of fibrotic ECM, by using both C2C12, a satellite cell- derived cell line, and primary muscle satellite cells. In C2CI2 cells, we found that expression of collagen type I mRNA decreases substantially during skeletal muscle differentiation. On a single-cell level, collagen type I and myogenin became mutually exclusive after 3 days in differentiation medium, whereas addition of collagen markedly suppressed differentiation of C2C12 cells. Primary cultures of satellite cells associated with isolated single fibers of the young (4 wk old) mdx dystrophic mouse and of C57BL/10ScSn wild-type controls expressed collagen type I and type III mRNA and protein. This pattern persisted in wild-type mice at all ages. But, curiously, in older (18-mo-old) mdx mice, although the myogenic cells continued to express type III collagen, type I expression became restricted to nonmyogenic cells. These cells typically constituted part of a cellular sheet surrounding the old mdx fibers. This combination of features strongly suggests that the progression to fibrosis in dystrophic muscle involves changes in the mechanisms controlling matrix production, which generates positive feedback that results in a reprogramming of myoblasts to a profibrotic function. [ABSTRACT FROM AUTHOR]

Abstract: Sparc is a secreted calcium-binding glycoprotein that regulates mineralization of bone tissues in mammals. In other vertebrates, its function remains largely unclear. Here, we describe the isolation, genomic organization and expression of the sparc gene in the teleost Medaka (Oryzias latipes), an established vertebrate model for developmental studies. During earliest stages of Medaka embryogenesis, sparc is expressed in the sclerotome compartment of the somites that gives rise to precursor cells of the axial skeleton. Importantly, in this area its expression precedes that of twist-1, which is a crucial regulator of osteoblast formation. Dynamic expression is also found in the floor plate of the neural tube and the notochord. Both structures are passed by migrating skeletal precursors shortly before they differentiate and form the vertebrae. In general, sparc is expressed before the formation and mineralization of bone elements and expression of bone markers like collagen type 1a in the fins and axial skeleton of Medaka embryos. It is also expressed in several non-skeletal tissues of embryos and adult fish, suggesting possible other functions not related to bone mineralization. Taken together, the Medaka sparc gene represents an excellent marker for early sclerotome development. Its restricted and highly dynamic expression suggests a novel function during migration of sclerotome cells and their differentiation into early vertebrae. This marker thus allows the analysis of early skeletal development and formation of extracellular bone matrix in this vertebrate model. [Copyright &y& Elsevier]

Abstract: The protein collagen is the most predominant and important protein of the skin and therefore its physicochemical and thermal properties are important to be known. DSC has been applied in order to study the thermal changes caused by using different concentrations of the gentamycin antibiotic in fibrous membranes FM, named AMATCOL at different scanning rates. The thermal effect consisting of several peaks of the fibrous collageneous membrane alone or with different percentages of drug is simplified to a broad peak after 24h equilibration time. The 35–70°C endothermic effect attributed to the collapse of the tripple-helical domain of collagen due to the dehydration is affected by the presence of gentamycin. The endothermic peaks due to vaporization of bound water at the temperatures of 90–120°C are also affected by the presence of gentamycin. This region consists of two peaks at low percentage of gentamycin and at higher percentages the peak near 120°C decreases in intensity and finally disappears. The re-absorption of the water is more significant in the preparations containing gentamycin after 24h equilibration time indicating that antibiotic makes a more stable complex with collagen molecules aiding this process. A minimum of re-absorption occurs when the concentration of gentamycin is 2% w/w in accordance with pore size and nitrogen gas permeability measurements. The collagen denaturation occurs at higher temperature when gentamycin is incorporated in fibrous membranes FM. This is an evidence that gentamycin stabilizes the cross-linkings between structural units (covalent, hydrophobic links) due to its interactions with collagen and water. Data resulted from differential scanning calorimetry (DSC) have been corroborated with those resulted from the porosity analysis. Specific morphology of fibrous collageneous membranes FM structure, containing macro-, micro-, and nano-pores resulted from freeze drying, acts on the gas and water vapor permeability, as well as water absorption. These characteristics are important in trans-dermal carriage of gentamycin contained in FM membranes. [Copyright &y& Elsevier]

: BackgroundTo assess the effects of halofuginone, a specific inhibitor of synthesis of collagen type 1, which is the major constituent of fibrosis, on esophageal stricture formation due to caustic ingestion.: MethodsSixty rats were divided into four equal groups: control group; sham laparotomy group; caustic injury without treatment group; caustic injury with halofuginone treatment group. Caustic injuries were done by 50% sodium hydroxide. Halofuginone was administered by the first postoperative day. All animals were sacrificed on day 21; and the results were evaluated by hydroxyproline levels, stenosis index, lumen diameter, histopathological evaluation, wall thickness, and animal weights.: ResultsMortality differences were significant comparing group 3 with group 1 and 2 (P = 0.006) and group 4 (P = 0.03). According to hydroxyproline levels, the differences are significantly higher (P <0.001) comparing group 3 with group 1, 2, and 4. The P value was considered significant in all other parameters (P <0.001) for all the groups but group 1 versus group 2 (P >0.05).: ConclusionsHalofuginone, a specific inhibitor of collagen type 1 synthesis, significantly reduced esophageal stricture occurrence. [Copyright &y& Elsevier]

Silicon deficiency in animals leads to bone defects. This element may therefore play an important role in bone metabolism. Silicon is absorbed from the diet as orthosilicic acid and concentrations in plasma are 5–20 μM. The in vitro effects of orthosilicic acid (0–50 μM) on collagen type 1 synthesis was investigated using the human osteosarcoma cell line (MG-63), primary osteoblast-like cells derived from human bone marrow stromal cells, and an immortalized human early osteoblastic cell line (HCC1). Collagen type 1 mRNA expression and prolyl hydroxylase activity were also determined in the MG-63 cells. Alkaline phosphatase and osteocalcin (osteoblastic differentiation) were assessed both at the protein and the mRNA level in MG-63 cells treated with orthosilicic acid. Collagen type 1 synthesis increased in all treated cells at orthosilicic acid concentrations of 10 and 20 μM, although the effects were more marked in the clonal cell lines (MG-63, HCCl 1.75- and 1.8-fold, respectively, P < 0.001, compared to 1.45-fold in the primary cell lines). Treatment at 50 μM resulted in a smaller increase in collagen type 1 synthesis (MG-63 1.45-fold, P = 0.004). The effect of orthosilicic acid was abolished in the presence of prolyl hydroxylase inhibitors. No change in collagen type 1 mRNA level was seen in treated MG-63 cells. Alkaline phosphatase activity and osteocalcin were significantly increased (1.5, 1.2-fold at concentrations of 10 and 20 μM, respectively, P < 0.05). Gene expression of alkaline phosphatase and osteocalcin also increased significantly following treatment. In conclusion, orthosilicic acid at physiological concentrations stimulates collagen type 1 synthesis in human osteoblast-like cells and enhances osteoblastic differentiation. [Copyright &y& Elsevier]

Form deprivation myopia (FDM) is characterized by loss of choroidal thickness (ChT), reduced choroidal blood perfusion (ChBP), and consequently scleral hypoxia. In some tissues, changes in levels of peroxisome proliferator-activated receptor γ (PPARγ) expression modulate hypoxia-induced pathological responses. We determined if PPARγ modulates FDM through changes in ChT, ChBP, scleral hypoxia-inducible transcription factor (HIF-1α) that in turn regulate scleral collagen type 1 (COL1) expression levels in guinea pigs. Myopia was induced by occluding one eye, while the fellow eye served as control. They received daily peribulbar injections of either the PPARγ antagonist GW9662, or the GW1929 agonist, with or without ocular occlusion for 4 weeks. Ocular refraction and biometric parameters were estimated at baseline, 2 and 4 weeks post-treatment. ChT and ChBP were measured at the 2- and 4-week time points. Western blot analysis determined the expression levels of scleral HIF-1α and COL1. GW9662 induced a myopic shift in unoccluded eyes. Conversely, GW1929 inhibited FDM progression without affecting the refraction in unoccluded eyes. GW9662 reduced both ChT and ChBP in unoccluded eyes, while GW1929 inhibited their declines in occluded eyes. Scleral HIF-1α expression rose in GW9662-treated unoccluded eyes whereas GW1929 reduced HIF-1α upregulation in occluded eyes. GW9662 downregulated scleral COL1 expression in unoccluded eyes, while GW1929 reduced their decreases in occluded eyes. Therefore, PPARγ modulates collagen expression levels and FDM through an inverse relationship between changes in PPARγ and HIF-1α expression levels. • PPARγ agonism and antagonism have opposing effect on refractive development and FDM. • PPARγ agonism reverses FD-induced declines of choroidal thickness and choroidal blood perfusion. • PPARγ agonism reverses FD-induced increases of scleral Hif-1α expression. • PPARγ agonism reverses FD-induced declines scleral collagen type 1 expression. [ABSTRACT FROM AUTHOR]