Expression Levels Of Collagen Type Research Articles

Effect of Botulinum Toxin Type A on TGF-β/Smad Pathway Signaling: Implications for Silicone-Induced Capsule Formation.

One of the most serious complications of breast surgery using implants is capsular contracture. Several preventive treatments have been introduced; however, the mechanism of capsule formation has not been resolved completely. The authors previously identified negative effects of botulinum toxin type A on capsule formation, expression of transforming growth factor (TGF)-β1, and differentiation of fibroblasts into myofibroblasts. Thus, the authors investigated how to prevent capsule formation by using botulinum toxin type A, particularly by means of TGF-β1 signaling, in human fibroblasts. In vitro, cultured human fibroblasts were treated with TGF-β1 and/or botulinum toxin type A. Expression of collagen, matrix metalloproteinase, and Smad was examined by Western blotting. The activation of matrix metalloproteinase was observed by gelatin zymography. In vivo, the effect of botulinum toxin type A on the phosphorylation of Smad2 in silicone-induced capsule formation was evaluated by immunocytochemistry. In vitro, the phosphorylation of Smad2 was inhibited by botulinum toxin type A treatment. The expression levels of collagen types 1 and 3 were inhibited by botulinum toxin type A treatment, whereas those of matrix metalloproteinase-2 and matrix metalloproteinase-9 were enhanced. Gelatin zymography experiments confirmed enhanced matrix metalloproteinase-2 activity in collagen degradation. In vivo, botulinum toxin type A treatment reduced capsule thickness and Smad2 phosphorylation in silicone-induced capsules. This study suggests that botulinum toxin type A plays an important role in the inhibition of capsule formation through the TGF-β/Smad signaling pathway. Therapeutic, V.

Effects of nano tantalum implants on inducing osteoblast proliferation and differentiation.

In the present study, we examined the effects of nano tantalum (Ta) dental implants on inducing osteoblast proliferation and differentiation. The MG-63 osteoblasts were divided into 3 groups after recovery, passage and storage: i) Osteoblast culturing group (control group); ii) osteoblast and titanium (Ti) implant co-culturing group (Ti group); and iii) osteoblast and Ta implant co-culturing group (Ta group). After 7 days, a scanning electron microscope was used to observe the growth status, number and morphological changes of the cells on the surfaces of the materials. An MTT assay was used to detect cell proliferation after culturing for 1, 3 and 7 days. ELISA assay was used to detect the levels of alkaline phosphatase (ALP) after 1, 3 and 7 days. Western blot analysis was used to detect the expression levels of collagen type I (Col-1) and osteocalcin after 1, 3 and 7 days. There was significant cell spreading on the surfaces of Ti and of Ta after 7 days, flat and with many pseudopodia. Additionally, there were more cell components in the Ta group. Concurrently, cell proliferation in the Ti and Ta groups increased. There was also an increase in the level of ALP and the expression level of Col-1 over time. The indexes of the Ta group were more apparent than those of the Ti group at each time-point, and the differences were statistically significant (p<0.05). In conclusion, compared with Ti implants, Ta implants induced more osteoblast proliferation and differentiation.

Construction of 3-D Cellular Multi-Layers with Extracellular Matrix Assembly Using Magnetic Nanoparticles.

Construction of 3-dimensional (3-D) engineered tissue is increasingly being investigated for use in drug discovery and regenerative medicine. Here, we developed multi-layered 3-D cellular assembly by using magnetic nanoparticles (MNP) isolated from Magnetospirillum sp. AMB-1 magnetotactic bacteria. Magnetized human dermal fibroblasts (HDFBs) were prepared by treatment with the MNP, induced to form 3-D assembly under a magnetic field. Analyses including LIVE/DEAD assay, transmission electron microscopy revealed that the MNP were internalized via clathrin-mediated endocytosis without cytotoxicity. The magnetized HDFBs could build 3-D structure as a function of seeding density. When the highest seeding density (5 × 105 cells/mm2 was used, the thickness of assembly was 41.90 ± 1.69 μm, with approximately 9.3 ± 1.6 cell layers being formed. Immunofluorescence staining confirmed homogeneous distribution of ECM and junction proteins throughout the 3-D assembly. Real-time PCR analysis showed decrease in expression levels of collagen types I and IV but increase in that of connexin 43 in the 3-D assembly compared with the 2-D culture. Finally, we demonstrated that the discernible layers can be formed hierarchically by serial assembly. In conclusion, our study showed that a multi-layered structure can be easily prepared using magnetically-assisted cellular assembly with highlighting cell-cell and cell-ECM communication.

MiR-29a Assists in Preventing the Activation of Human Stellate Cells and Promotes Recovery From Liver Fibrosis in Mice.

The microRNA-29 (miR-29) family is known to suppress the activation of hepatic stellate cells (HSCs) and reversibly control liver fibrosis; however, the mechanism of how miR-29a controls liver fibrosis remains largely unknown. This study was conducted to clarify the mechanism of anti-fibrotic effect of miR-29a and to explore if miR-29a is a promising candidate for nucleic acid medicine against liver fibrosis. Two liver fibrosis murine models (carbon tetrachloride or thioacetamide) were used. MiR-29a mixed with atelocollagen was systemically administered. Hepatic fibrosis was evaluated by histological analysis and the expression levels of fibrosis-related genes. We observed that miR-29a treatment dramatically accelerated the reversion of liver fibrosis in vivo. Additionally, miR-29a regulated the mRNA expression of collagen type I alpha 1 (COL1A1) and platelet-derived growth factor C (PDGFC). We also noted that miR-29a significantly suppressed COL1A1 mRNA expression and cell viability and significantly increased caspase-9 activity (P < 0.05) in LX-2 cells. Pretreatment of miR-29a inhibited activation of LX-2 cell by transforming growth factor beta treatment. MiR-29a exhibited anti-fibrotic effect without cell toxicity in vivo and directly suppressed the expression of PDGF-related genes as well as COL1A1 and induced apoptosis of LX-2 cells. MiR-29a is a promising nucleic acid inhibitor to target liver fibrosis.

Expressing human SHOX in Shox2SHOX KI/KI mice leads to congenital osteoarthritis‑like disease of the temporomandibular joint in postnatal mice.

The temporomandibular joint (TMJ), a unique synovial joint whose development differs from that of other synovial joints, develops from two distinct mesenchymal condensations that grow toward each other and ossify through different mechanisms. The short stature homeobox 2 (Shox2) gene serves an important role in TMJ development and previous studies have demonstrated that Shox2SHOX KI/KI mice display a TMJ defective phenotype, congenital dysplasia and premature eroding of the articular disc, which is clinically defined as a TMJ disorder. In the present study, Shox2SHOX KI/KI mouse models were used to investigate the mechanisms of congenital osteoarthritis (OA)-like disease during postnatal TMJ growth. Shox2SHOX KI/KI mice were observed to develop a severe muscle wasting syndrome from day 7 postnatal. Histological examination indicated that the condyle and glenoid fossa of Shox2SHOX KI/KI mice was reduced in size in the second week after birth. The condyles of Shox2SHOX KI/KI mice exhibited reduced expression levels of collagen type II and Indian hedgehog, and increased expression of collagen type I. A marked increase in matrix metalloproteinase 9 (MMP9) and MMP13 in the condyles was also observed. These cellular and molecular defects may contribute to the observed (OA)-like phenotype of Shox2SHOX KI/KI mouse TMJs.

Effects of the Ultra-High-Frequency Electrical Field Radiofrequency Device on Mouse Skin: A Histologic and Molecular Study.

Radiofrequency technology is one of the most recently developed methods for noninvasive skin tightening and facial contouring, and works by generating thermal energy in the deep dermis. Although clinical improvements have been reported using radiofrequency devices, there are few histologic and molecular studies about the mechanisms of dermal collagen remodeling. The authors investigated the histologic effects of an ultra-high-frequency electrical field (40.68 MHz) radiofrequency device (Polargen) on collagen remodeling in hairless mouse skin and evaluated its relative molecular mechanism. The radiofrequency was applied to the dorsal skin of hairless mice three times per week for 2 weeks. At 21 days after initial treatment, treated skin and nontreated control skin samples were excised for semiquantitative analysis of histologic features, including collagen. The authors also checked the mRNA expression levels of collagen type 1, transforming growth factor (TGF)-β, matrix metalloproteinase-1, vascular endothelial growth factor, tumor necrosis factor-α, and interleukin-1. Histologic examination revealed epidermal hyperplasia, increased collagen staining, and fat atrophy in treated skin area compared with the nontreated skin area. In addition, mRNA expression of collagen type І, TGF-β, and vascular endothelial growth factor in radiofrequency-treated areas was significantly increased compared with that in untreated control areas (p < 0.05, p < 0.05, and p < 0.01, respectively). These results suggest that the device may facilitate replacement of subcutaneous fat tissue with new collagen in association with the increased mRNA levels in TGF-β and vascular endothelial growth factor. Therefore, this device may effectively reduce adipose tissue and achieve facial contouring in addition to skin tightening.

Indirect coculture of stem cells with fetal chondrons using PCL electrospun nanofiber scaffolds

In vitro coculture system provides a powerful tool for tissue engineering. In this study, we evaluated the gene expressions of human adipose-derived stem cells (ASCs) on polycaprolactone (PCL) scaffold in coculture model with fetal chondrons. Electrospun PCL scaffolds (900 nm fiber diameter) were created and human infrapatellar fat pad-adipose-derived stem cells (IPFP-ASCs) were seeded on these scaffolds. Scanning electron microscopy (SEM) showed attachment of human IPFP–ASCs to scaffold. IPFP-ASCs on scaffolds were cocultured with fetal chondrons in transwell. Gene expressions were investigated using real-time polymerase chain reaction (real-time PCR). In comparison with control group, the expression level of collagen type 2 and aggrecan were significantly decreased but Indian Hedgehog(IHH) significantly increased (P < 0.05).These findings may interpreted that IPFP-ASCs seeded on PCL scaffold, in cocultures with fetal chondrons are tending toward osteogenesis rather than chondrogenesis.

Sesamin Ameliorates High-Fat Diet-Induced Dyslipidemia and Kidney Injury by Reducing Oxidative Stress.

The study explored the protective effect of sesamin against lipid-induced renal injury and hyperlipidemia in a rat model. An animal model of hyperlipidemia was established in Sprague-Dawley rats. Fifty-five adult Sprague-Dawley rats were divided into five groups. The control group was fed a standard diet, while the other four groups were fed a high-fat diet for 5 weeks to induce hyperlipidemia. Three groups received oral sesamin in doses of 40, 80, or 160 mg/(kg·day). Seven weeks later, the blood lipids, renal function, antioxidant enzyme activities, and hyperoxide levels in kidney tissues were measured. The renal pathological changes and expression levels of collagen type IV (Col-IV) and α-smooth muscle actin (α-SMA) were analyzed. The administration of sesamin improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, apolipoprotein-B, oxidized-low-density lipoprotein, and serum creatinine levels in hyperlipidemic rats, while it increased the high-density lipoprotein cholesterol and apolipoprotein-A levels. Sesamin reduced the excretion of 24-h urinary protein and urinary albumin and downregulated α-SMA and Col-IV expression. Moreover, sesamin ameliorated the superoxide dismutase activity and reduced malondialdehyde levels in kidney tissue. Sesamin could mediate lipid metabolism and ameliorate renal injury caused by lipid metabolism disorders in a rat model of hyperlipidemia.

Characterization of primary chondrocytes harvested from hips with femoroacetabular impingement

Acetabular chondral lesions are common in patients with femoroacetabular impingement (FAI) syndrome. The aim of this study was (1) to evaluate the proliferation potential of primary human chondrocytes (hC) derived from both acetabular and femoral site and (2) to validate cellular differentiation during three-dimensional (3D) cultivation as a prerequisite for autologous matrix-assisted cartilage regeneration of the hip joint. hC were isolated from cartilage samples obtained from N=6 patients during offset reconstruction. Proteoglycan content was assessed by Safranin-O staining. Proliferation and cell viability were quantified by microscopic cell counting and Trypan Blue exclusion. Messenger ribonucleic acid (mRNA) expression levels of collagen type 1 and 2, aggrecan (ACAN), and interleukin-1β (IL-1β) genes were assessed upon monolayer cultivation, after 48h/4-10°C - transport simulation and after 14 days of 3D hydrogel cultivation. Primary hC from acetabular and femoral damaged sites were viable. No significant intergroup differences were observed concerning cell viability (>95%) after monolayer cultivation and transport simulation. Harvest yields from acetabular and femoral cartilage samples were comparable to that known from knee joints (mean±standard deviation (SD), 13.4×10(6)±5×10(6) cells per culture vs 20×10(6) cells). Redifferentiation was induced during 3D hydrogel cultivation as observed by increased levels of collagen II (1000-fold) and ACAN (10-fold) gene vs monolayer cultivation (P<0.001). hC derived from damaged acetabular and femoral site are qualified for autologous matrix-assisted cartilage transplantation paving the way for cell-based cartilage regeneration in FAI patients.

AIMP1 downregulation restores chondrogenic characteristics of dedifferentiated/degenerated chondrocytes by enhancing TGF-β signal.

Dedifferentiation and degeneration of chondrocytes critically influences the efficiency of cartilage repair. One of the causes is the defect of transforming growth factor (TGF)-β signaling that promotes chondrogenic differentiation and degeneration. In the present study, we found that aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1) negatively regulates TGF-β signaling via interactions with Smad2 and Smad3 in immunoprecipitation assay and luciferase assay. In addition, we observed that the AIMP1 expression level was significantly increased in osteoarthritis (OA) patient-derived degenerated chondrocytes compared with healthy control. So, we hypothesized that downregulation of AIMP1 using small-interfering RNA (siRNA) technology in dedifferentiated (collected at passage #6) and degenerated (obtained from OA-affected areas) chondrocytes could lead to recover TGF-β signaling in both chondrocytes. Indeed, AIMP1 downregulation restored TGF-β signaling by promoting phosphorylation of Smad2 and Smad3, which shows redifferentiated characteristics in both dedifferentiated and degenerated chondrocytes. Additionally, implantation analyses using in vivo mouse model clearly showed that AIMP1 downregulation resulted in the increased chondrogenic potential as well as the enhanced cartilage tissue formation in both dedifferentiated and degenerated chondrocytes. Histological analyses clarified that AIMP1 downregulation increased expression levels of collagen type II (Col II) and aggrecan, but not Col I expression. Taken together, these data indicate that AIMP1 downregulation using siRNA is a novel tool to restore TGF-β signaling and thereby increases the chondrogenic potential of dedifferentiated/degenerated chondrocytes, which could be further developed as a therapeutic siRNA to treat OA.

Sequential changes in autophagy in diabetic cardiac fibrosis.

Autophagy is considered to be associated with cardiac fibrosis. However, whether autophagy accelerates or ameliorates fibrosis remains to be elucidated. In the present study, 36 rats were divided into two groups: Control rats and diabetic rats. The diabetic rats were established by feeding the animals a high fat diet combined with streptozotocin. From the two groups, six rats were sacrificed after 1, 6 and 7 months. Cardiac systolic functions were measured. The collagen volume fraction was calculated using Masson's trichome staining and the mRNA expression levels of type‑I and type‑III collagen were measured using reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) to assess the levels of cardiac fibrosis. The protein contents of microtubule‑associated protein 1 light chain 3 (LC3) and sequestosome 1 (P62) were evaluated using western blotting, and the mRNA expression of Beclin 1 was measured using RT‑qPCR, in order to assess autophagy. The results revealed that, in the diabetic rats, cardiac fibrosis developed and cardiac systolic function was reduced. In the hearts of the diabetic rats, the mRNA expression levels of collagen type I and III, and Beclin1 were upregulated; the ratio of the protein level of LC3‑II/LC3‑I was increased and the content of P62 was decreased. All the changes were aggravated as time increased. The changes in autophagy were correlated with those of cardiac fibrosis, suggesting that autophagy may have a synergistic role in diabetic cardiac fibrosis.

L(59) TGF-β LAP degradation products serve as a promising blood biomarker for liver fibrogenesis in mice.

BackgroundHepatic fibrosis, which is the excessive accumulation of extracellular matrices (ECMs) produced mainly from activated hepatic stellate cells (HSCs), develops to cirrhosis over several decades. There are no validated biomarkers that can non-invasively monitor excessive production of ECM (i.e., fibrogenesis). Transforming growth factor (TGF)-β, a key driver of fibrogenesis, is produced as an inactive latent complex, in which active TGF-β is enveloped by its pro-peptide, the latency-associated protein (LAP). Thus, active TGF-β must be released from the complex for binding to its receptor and inducing ECM synthesis. We recently reported that during the pathogenesis of liver fibrosis, plasma kallikrein (PLK) activates TGF-β by cleavage between R58 and L59 residues within LAP and that one of its by-products, the N-terminal side LAP degradation products ending at residue R58 (R58 LAP-DPs), can be detected mainly around activated HSCs by specific antibodies against R58 cleavage edges and functions as a footprint of PLK-dependent TGF-β activation. Here, we describe a sandwich enzyme-linked immunosorbent assay (ELISA) that detects the other by-products, the C-terminal side LAP-DPs starting from residue L59 (L59 LAP-DPs). We demonstrated that the L59 LAP-DPs are a potentially novel blood biomarker reflecting hepatic fibrogenesis.ResultsWe established a specific sandwich ELISA to quantify L59 LAP-DPs as low as 2 pM and measured L59 LAP-DP levels in the culture media of a human activated HSC line, TWNT-4 cells. L59 LAP-DPs could be detected in their media, and after treatment of TWNT-4 cells with a TGF-β receptor kinase inhibitor, SB431542, a simultaneous reduction was observed in both L59 LAP-DP levels in the culture media and the mRNA expression levels of collagen type (I) α1. In carbon tetrachloride- and bile duct ligation-induced liver fibrosis models in mice, plasma L59 LAP-DP levels increased prior to increase of hepatic hydroxyproline (HDP) contents and well correlated with α-smooth muscle actin (αSMA) expression in liver tissues. At this time, αSMA-positive cells as well as R58 LAP-DPs were seen in their liver tissues.ConclusionsL59 LAP-DPs reflect PLK-dependent TGF-β activation and the increase in αSMA-positive activated HSCs in liver injury, thereby serving as a novel blood biomarker for liver fibrogenesis.Electronic supplementary materialThe online version of this article (doi:10.1186/s13069-015-0034-9) contains supplementary material, which is available to authorized users.

Aldehyde dehydrogenase-2 protects against myocardial infarction-related cardiac fibrosis through modulation of the Wnt/β-catenin signaling pathway.

BackgroundAldehyde dehydrogenase-2 (ALDH2) has a protective effect on ischemic heart disease. Here, we examined the protective effects of ALDH2 on cardiac fibrosis through modulation of the Wnt/β-catenin signaling pathway in a rat model of myocardial infarction (MI).MethodsWistar rats were divided into the sham (control), MI (model), and ALDH2 activator (Alda-1) groups. After 10 days of treatment, the left ventricular (LV) remodeling parameters of each animal were evaluated by echocardiography. Myocardial fibrosis was evaluated by Masson’s trichrome staining and Sirius Red staining. Expression levels of collagen types I and III and α-smooth muscle actin (α-SMA) were examined. Finally, the expression and activity of ALDH2 and the levels of several Wnt-related proteins and genes, such as phosphoglycogen synthase kinase (GSK)-3β, GSK-3β, β-catenin, Wnt-1, WNT1-inducible signaling-pathway protein 1, and tumor necrosis factor (TNF)-α, were also analyzed.ResultsAfter MI, the heart weight/body weight ratio, LV dimension at end diastole, and LV dimension at end systole were decreased, while the LV ejection fraction and LV fractional shortening were increased in the Alda-1 group. Myocardial fibrosis was also reduced in the Alda-1 group, accompanied by decreased expression collagen types I and III and α-SMA. β-Catenin, phosphorylated GSK-3β, and Wnt-1 levels were significantly increased in the model group. Interestingly, this alteration was partly reversed by Alda-1 treatment. Immunohistochemical staining showed that numerous WNT1-inducible signaling-pathway protein 1 (WISP-1)- and TNF-α-positive cells were found in the model group. However, few WISP-1- and TNF-α-positive cells were detected in the Alda-1 group.ConclusionThe reduction of cardiac fibrosis and the down-regulation of β-catenin, phosphorylated GSK-3β, Wnt-1, and WISP-1 may be mediated by increased ALDH2 activity, leading to reduction of MI-related cardiac fibrosis.

Human Dermal Stem/Progenitor Cell-Derived Conditioned Medium Improves Senescent Human Dermal Fibroblasts.

Adult skin stem cells are recognized as potential therapeutics to rejuvenate aged skin. We previously demonstrated that human dermal stem/progenitor cells (hDSPCs) with multipotent capacity could be enriched from human dermal fibroblasts using collagen type IV. However, the effects of hDSPCs on cellular senescence remain to be elucidated. In the present study, we investigated whether conditioned medium (CM) collected from hDSPC cultures (hDSPC-CM) exhibits beneficial effects on senescent fibroblasts. We found that hDSPC-CM promoted proliferation and decreased the expression level of senescence-associated β-galactosidase in senescent fibroblasts. In addition, p53 phosphorylation and p21 expression were significantly reduced in senescent fibroblasts treated with hDSPC-CM. hDSPC-CM restored the expression levels of collagen type I, collagen type III, and tissue inhibitor of metalloproteinase, and antagonized the increase of matrix metalloproteinase 1 expression. Finally, we demonstrated that hDSPC-CM significantly reduced reactive oxygen species levels by specifically up-regulating the expression level of superoxide dismutase 2. Taken together, these data suggest that hDSPC-CM can be applied as a potential therapeutic agent for improving human aged skin.

Adiponectin attenuates lung fibroblasts activation and pulmonary fibrosis induced by paraquat.

Pulmonary fibrosis is one of the most common complications of paraquat (PQ) poisoning, which demands for more effective therapies. Accumulating evidence suggests adiponectin (APN) may be a promising therapy against fibrotic diseases. In the current study, we determine whether the exogenous globular APN isoform protects against pulmonary fibrosis in PQ-treated mice and human lung fibroblasts, and dissect the responsible underlying mechanisms. BALB/C mice were divided into control group, PQ group, PQ + low-dose APN group, and PQ + high-dose APN group. Mice were sacrificed 3, 7, 14, and 21 days after PQ treatment. We compared pulmonary histopathological changes among different groups on the basis of fibrosis scores, TGF-β1, CTGF and α-SMA pulmonary content via Western blot and real-time quantitative fluorescence-PCR (RT-PCR). Blood levels of MMP-9 and TIMP-1 were determined by ELISA. Human lung fibroblasts WI-38 were divided into control group, PQ group, APN group, and APN receptor (AdipoR) 1 small-interfering RNA (siRNA) group. Fibroblasts were collected 24, 48, and 72 hours after PQ exposure for assay. Cell viability and apoptosis were determined via Kit-8 (CCK-8) and fluorescein Annexin V-FITC/PI double labeling. The protein and mRNA expression level of collagen type III, AdipoR1, and AdipoR2 were measured by Western blot and RT-PCR. APN treatment significantly decreased the lung fibrosis scores, protein and mRNA expression of pulmonary TGF-β1, CTGF and α-SMA content, and blood MMP-9 and TIMP-1 in a dose-dependent manner (p<0.05). Pretreatment with APN significantly attenuated the reduced cell viability and up-regulated collagen type III expression induced by PQ in lung fibroblasts, (p<0.05). APN pretreatment up-regulated AdipoR1, but not AdipoR2, expression in WI-38 fibroblasts. AdipoR1 siRNA abrogated APN-mediated protective effects in PQ-exposed fibroblasts. Taken together, our data suggests APN protects against PQ-induced pulmonary fibrosis in a dose-dependent manner, via suppression of lung fibroblast activation. Functional AdipoR1 are expressed by human WI-38 lung fibroblasts, suggesting potential future clinical applicability of APN against pulmonary fibrosis.

Characteristics of stem cells derived from rat fascia: in vitro proliferative and multilineage potential assessment.

Fascia‑derived stem cells (FDSCs) were previously isolated from the fascia of the gluteus maximus of the rat. However, the use of FDSCs as a cell source for musculoskeletal tissue engineering has not been compared with that of adipose‑derived stem cells (ADSCs) and bone marrow‑derived mesenchymal stem cells (BMSCs). Therefore, the present study aimed to compare the mesenchymal stem cell (MSC) and self‑renewal stem cell markers, proliferative capacity and multilineage differentiation potential of these stem cells in vitro. The MSC and embryonic stem cell (ESC) marker profiles were compared using flow cytometry and quantitative polymerase chain reaction (qPCR). Their proliferative capacities were compared using 5‑bromo‑2'‑deoxyuridine and MTT assays. Their osteogenic, adipogenic and chondrogenic differentiation potentials were compared using standard staining assays and qPCR. The FDSCs possessed similar cell morphology and immunophenotypic profiles with BMSCs and ADSCs. FDSCs demonstrated a similar expression pattern of ESC markers with ADSCs, which has higher expression of sex determining region Y‑box (Sox)2 and octamer‑binding transcription factor 4, and lower expression of Krüppel‑like factor 4, when compared with BMSCs. FDSCs exhibited higher proliferation under serum‑deprived conditions (0.5% FBS growth medium), and attained higher expression levels of collagen type I, α 2 and type II, α 1 as well as Sox9 mRNA than ADSCs and BMSCs upon chondrogenic induction. An increased amount of proteoglycan deposition was also observed in the FDSC group. However, lower levels of adipogenic and osteogenic marker expression in FDSCs were detected compared with ADSCs and BMSCs upon adipogenic and osteogenic induction, respectively. FDSCs possessed high chondrogenic potential, low osteogenic and adipogenic differentiation potential and were responsive to the induction signals for collagen‑rich fascial structure regeneration. Therefore, FDSCs may represent an improved alternative cell source to conventional ADSCs and BMSCs for musculoskeletal tissue repair and tissue engineering, particularly for collagen‑rich structures with poor vasculature.

Losartan attenuates paraquat-induced pulmonary fibrosis in rats.

Paraquat (PQ) is one of the most widely used herbicides in the world and can cause pulmonary fibrosis in the cases with intoxication. Losartan, an angiotensin II type 1 receptor antagonist, has beneficial effects on the treatment of fibrosis. The aim of this study was to examine the effect of losartan on pulmonary fibrosis in PQ-intoxicated rats. Adult male Sprague Dawley rats (n = 32, 180-220 g) were randomly assigned to four groups: (i) control group; (ii) PQ group; (iii) PQ + losartan 7d group; and (iv) PQ + losartan 14d group. Losartan treatment (intragastrically (i.g.), 10 mg/kg) was performed for 7 and 14 days after a single i.g. dose of 40 mg/kg PQ. All rats were killed on the 16th day, and hematoxylin-eosin and Masson's trichrome staining were used to examine lung injury and fibrosis. The levels of hydroxyproline and transforming growth factor β1 (TGF-β1), matrix metallopeptidase 9 (Mmp9), and tissue inhibitor of metalloproteinase 1 (TIMP-1) messenger RNA (mRNA) expression and relative expression levels of collagen type I and III were also detected. PQ caused a significant increase in hydroxyproline content, mRNA expression of TGF-β1, Mmp9, and TIMP-1, and relative expression levels of collagen type I and III ( p < 0.05), while losartan significantly decreased the amount of hydroxyproline and downregulated TGF-β1, Mmp9, and TIMP-1 mRNA and collagen type I and III expressions ( p < 0.05). Histological examination of PQ-treated rats showed lung injury and widespread inflammatory cell infiltration in the alveolar space and pulmonary fibrosis, while losartan could markedly reduce such damage and prevent pulmonary fibrosis. The results of this study indicated that losartan could reduce lung damage and prevent pulmonary fibrosis induced by PQ.

High-voltage pulsed current stimulation enhances wound healing in diabetic rats by restoring the expression of collagen, α-smooth muscle actin, and TGF-β1.

Impaired wound healing is a common complication of diabetes mellitus and a major morbidity that leads to pain and severely diminished quality of life. Diabetic wounds are commonly associated with defective immune cell responses or abnormality of extracellular matrix. Various types of electrical stimulation interventions have been used to promote tissue healing. However, it is unclear whether high-voltage pulsed current stimulation (HVPCS) enhances diabetic wound healing. In this study, the effects of HVPCS on wound healing were investigated in diabetic rats. Three groups of rats (10 per group) were used: non-diabetic control, diabetic control, and diabetic rats that were administered HVPCS for 40 minutes daily for 1 week. Rats from control groups were administered sham interventions. Dorsal incision wounds were generated in all animals, and wound-healing rate was determined during one-week intervention. After interventions, we measured the relative expression levels of collagen type I (collagen-I), α-smooth muscle actin (α-SMA), and transforming growth factor-β1 (TGF-β1) mRNAs in the wounded skin. Wound closure was delayed in diabetic control rats compared to the non-diabetic control rats, and the diabetic control rats showed the reduced expression levels of collagen-I, α-SMA and TGF-β1 mRNAs. Importantly, compared to diabetic control rats, rats with HVPCS showed accelerated wound closure and healing (p < 0.01) and restored expression levels of collagen-I (p = 0.02), α-SMA (p = 0.04), and TGF-β1 (p = 0.01) mRNAs. In conclusion, HVPCS may be beneficial for enhancing the healing of diabetic wounds by restoring the expression levels of TGF-β1, collagen-I, and α-SMA.

The long head of the biceps tendon is a suitable cell source for tendon tissue regeneration.

IntroductionTendon tissue engineering (TTE) tries to produce tendinous tissue of high quality to replace dysfunctional tissue. One possible application of TTE might be the replacement of ruptured tissue of the rotator cuff. Autologous tenocytes seem to be most suitable as no differentiation in vitro is necessary. Today it is still uncertain if there is a difference between tendon-derived cells (TDC) of different native tissues. Moreover, the search for suitable scaffolds is another important issue in TTE.Material and methodsThis study compared TDC of the long head of the biceps tendon (LHB), the anterior cruciate ligament (ACL) and the tendon of the musculus semitendinosus (TMS). The TDC were isolated using the cell migration method. Cell morphology was assessed using light microscopy and gene expression was performed using polymerase chain reaction (PCR). Afterwards, cell seeding efficiency and proliferation were tested on a collagen I scaffold using the WST-1 assay. Results were confirmed using H + E staining.ResultsThe TDC of the LHB showed higher expression levels of collagen type I and decorin (p < 0.01) compared to TDC of other origin. Results showed efficient cell seeding and proliferation within the scaffold. Proliferation within the scaffold was not as high as when cells were cultivated without a scaffold.ConclusionsThe TDC of the LHB seems to be the most suitable cell source. Further research is necessary to find out if the results can be transferred to an in vivo model. The new collagen I scaffold seems to offer an opportunity to combine good biocompatibility and mechanical strength.

The effect of platelet rich plasma on chondrogenic differentiation of human adipose derived stem cells in transwell culture.

Platelet-rich plasma (PRP) has recently emerged as a promising strategy in regenerative medicine due to its multiple endogenous growth factors. Little is known about the role of PRP as a promoter in chondrogenesis of human adipose derived stem cells (hADSCs). The aim of this study was to determine whether PRP may be considered as a natural and easy achievable source of growth factors to promote the chondrogenic differentiation of hADSCs in Transwell culture. Materials and Methods : Biochemical, immunohistological and molecular assays were used to evaluate the effect of different concentrations (5%, 10%, and 15%) of PRP on chondrogenic differentiation of hADSCs in Transwell culture. Results : The cells in the presence of 10% PRP produced markedly higher amounts of GAG and DNA, in comparison to the control group. PRP also increased chondrogenic markers in these cells, such as sox-9, aggrecan and collagen type II. A high expression level of collagen type X as a hypertrophic marker was observed in cartilage produced by using either PRP or TGF-β1. Conclusion : Our findings indicate that autologous PRP at an optimum concentration had beneficial effects on differentiation of hADSCs in Transwell culture. Further, in vivo studies are necessary to fully define the clinical implications of PRP.