Tripeptide/Hexapeptide Topical in Esthetics: Evidence behind the Skincare Formulation.

The skincare market, which is projected to be worth over $180 billion by 2024, has experienced a recent rise in formulations utilizing peptides. These products have been marketed to consumers as offering many esthetic benefits. We review the literature for a tripeptide and hexapeptide formulation that has been shown to offer improved healing and clinical outcomes in conjunction with resurfacing and cryolipolysis, as well as demonstrating benefit for cutaneous rejuvenation.

[Mechanisms of the wound-healing action of native collagen type I in ischemic model full-thickness skin wounds on the example - medical devices Collost «(part I)]. / Mekhanizmy ranozazhivlyayushchego deistviya nativnogo kollagena I tipa v modeli ishemizirovannykh polnosloinykh ran kozhi na primere meditsinskogo izdeliya «Kollost¼. (Chast' I).

Active collagen type I successfully used in regenerative medicine. However, despite the large amount of material of cellular and molecular mechanisms underlying skin repair, the molecular mechanisms of wound healing with use collagen type I, not studied enough. PURPOSE OF THE STUDY: To study the mechanism of the native collagen type I wound-healing action of native type I collagen on the example of the medical device Collost (7% gel) in a model of the rats difficult-to-heal skin wounds. MATERIAL AND METHODS: Male rats in population SD (72 individuals) surgically formed an ischemic dorsal skin flap (3×10 cm) with two full-thickness skin wounds 6 mm in diameter.The trained animals divided into 2 groups: in the experimental group, medical device Collost (gel) applied once after the operation, in the control group - a standard medical device for comparison. The dynamics of wound healing assessed, the number of M2 macrophages, myofibroblasts, vascularization and expression of the main markers of the repair process in the wound tissues and time points for assessment were: after 3, 7 and 14 days after operation using macroscopic, immunohistochemical, and molecular methods. RESULTS: It has been established that the mechanism of action of native collagen type I is associated with the acceleration of the appearance of «progenitorous¼ M2-macrophages in the wound tissues, decrease in the severity of inflammation or reduction in the duration of the inflammatory stage of the repair process, change in the expression spectrum of number of growth factors, an acceleration of neovasculogenesis. CONCLUSION: In this work, on the modern experimental model shown regenerative efficiency of a medical device based on collagen type I and described the molecular and cellular processes of wound healing when using it It has been shown that the acceleration of wound healing processes occurs when using a medical device based on native collagen type 1, it is also accompanied by a better aesthetic closure of the damaged skin area.

Type I collagen hydrogels as a delivery matrix for royal jelly derived extracellular vesicles.

Throughout the last decade, extracellular vesicles (EVs) have become increasingly popular in several areas of regenerative medicine. Recently, Apis mellifera royal jelly EVs (RJ EVs) were shown to display favorable wound healing properties such as stimulation of mesenchymal stem cell migration and inhibition of staphylococcal biofilms. However, the sustained and effective local delivery of EVs in non-systemic approaches - such as patches for chronic cutaneous wounds - remains an important challenge for the development of novel EV-based wound healing therapies. Therefore, the present study aimed to assess the suitability of type I collagen -a well-established biomaterial for wound healing - as a continuous delivery matrix. RJ EVs were integrated into collagen gels at different concentrations, where gels containing 2 mg/ml collagen were found to display the most stable release kinetics. Functionality of released RJ EVs was confirmed by assessing fibroblast EV uptake and migration in a wound healing assay. We could demonstrate reliable EV uptake into fibroblasts with a sustained pro-migratory effect for up to 7 d. Integrating fibroblasts into the RJ EV-containing collagen gel increased the contractile capacity of these cells, confirming availability of RJ EVs to fibroblasts within the collagen gel. Furthermore, EVs released from collagen gels were found to inhibit Staphylococcus aureus ATCC 29213 biofilm formation. Overall, our results suggest that type I collagen could be utilized as a reliable, reproducible release system to deliver functional RJ EVs for wound healing therapies.

A modular programmed biphasic dual-delivery system on 3D ceramic scaffolds for osteogenesis in vitro and in vivo.

Single-factor delivery is the most common characteristic of bone tissue engineering techniques. However, bone regeneration is a complex process requiring multiple factors and specialized release mechanisms. Therefore, the development of a dual-delivery system allowing for programmed release kinetics would be highly desirable. Improvement of the molarity and versatility of the delivery system has rarely been studied. Herein, we report the development of a novel, modular programmed biphasic dual-release system (SCB), carrying a BMP2 and an engineered collagen I-derived recognition motif (Stath-DGEA), with a self-remodification feature on hydroxyapatite (HA)-based materials. The SCB system was loaded onto an additive manufactured (AM) scaffold in order to evaluate its bifactor osteogenic potential and its biphasic release behavior. Further, the biomechanical properties of the scaffold were studied by using the fluid-structure interaction (FSI) method. Section fluorescent labeling revealed that the HA scaffold has a relatively higher density and efficiency. Additionally, the results of the release and inhibition experiment suggested that the SCB system could facilitate the sustained release of therapeutic levels of two factors during the initial stage of implantation, thereby exhibiting a rapid high-dose release pattern at a specific time point during the second stage. The FSI prediction model indicated that the scaffold provides an excellent biomimetic mechanical and fluid dynamic microenvironment to promote osteogenesis. Our results indicated that incorporation of BMP2 with Stath-DGEA in the biphasic SCB system could have a synergetic effect in promoting the adhesion, proliferation, and differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro, under staged stimulations. Further, in vivo studies in both ectopic and orthotopic rat models showed that the SCB system loaded onto an AM scaffold could enhance osteointegration and osteoinduction throughout the osteogenic process. Thus, the novel synthetic SCB system described herein used on an AM scaffold provides a biomimetic extracellular environment that enhances bone regeneration and is a promising multifunctional, dual-release platform.

Concomitant ankle instability has a negative impact on the quality of life in patients with osteochondral lesions of the talus: data from the German Cartilage Registry (KnorpelRegister DGOU).

PURPOSE: The purpose of this study was to compare patients with osteochondral lesions of the talus (OCLT) with and without concomitant chronic ankle instability (CAI). METHODS: Data from the German Cartilage Registry (KnorpelRegister DGOU) for 63 patients with a solitary OCLT were used. All patients received autologous matrix-induced chondrogenesis (AMIC) for OCLT treatment. Patients in group A received an additional ankle stabilisation, while patients in group B received AMIC alone. Both groups were compared according to demographic, lesion-related, and therapy-related factors as well as baseline clinical outcome scores at the time of surgery. The Foot and Ankle Ability Measure (FAAM), the Foot and Ankle Outcome Score (FAOS), and the Numeric Rating Scale for Pain (NRS) were used. RESULTS: Patients in group A were older compared to group B [median 34 years (range 20-65 years) vs. 28.5 years (range 18-72 years)]; the rate of trauma-associated OCLTs was higher (89.7% vs. 38.3%); more patients in group A had a previous non-surgical treatment (74.1% vs. 41.4%); and their OCLT lesion size was smaller [median 100 mm2 (range 15-600 mm2) vs. 150 mm2 (range 25-448 mm2)]. Most OCLTs were located medially in the coronary plane and centrally in the sagittal plane in both groups. Patients in group A had worse scores on the FAOS quality-of-life subscale compared to patients in group B. CONCLUSION: Patients with OCLT with concomitant CAI differ from those without concomitant CAI according to demographic and lesion-related factors. The additional presence of CAI worsens the quality of life of patients with OCLT. Patients with OCLT should be examined for concomitant CAI, so that if CAI is present, it can be integrated into the treatment concept. LEVEL OF EVIDENCE: IV.

Effects of cell phenotype and seeding density on the chondrogenic capacity of human osteoarthritic chondrocytes in type I collagen scaffolds.

OBJECTIVE: Matrix-associated autologous chondrocyte implantation (MACI) achieves good clinical efficacy in young patients with focal cartilage injury; however, phenotypic de-differentiation of chondrocytes cultured in monolayer and the treatment of older OA patients are still challenges in the field of cartilage tissue engineering. This study aimed to assess the in vitro re-differentiation potential and in vivo chondrogenic capacity of human OA chondrocytes inoculated into collagen I scaffolds with different cellular phenotypes and seeding densities. METHODS: OA chondrocytes and articular chondrocyte-laden scaffolds were cultured over 2 weeks in in vitro. Reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and histological staining were used to detect the mRNA expression profiles and extracellular matrix secretion of chondrocyte-specific markers. OA chondrocyte-laden collagen I scaffolds with different cellular phenotypes, and seeding densities were implanted into SCID mice over 4 weeks to evaluate the chondrogenic capacity in vivo. RESULTS: Increased COL2a1, ACAN, COMP, SOX9, and BMP2 expression levels and decreased COL1a1, VCAN, MMP13, and ADAMTS5 amounts were observed in OA chondrocytes seeded in collagen I scaffolds; Implantation of phenotypically superior OA chondrocytes in collagen I scaffolds at high density could improve the chondrogenic capacity of human OA chondrocytes, as confirmed by RT-qPCR assessed gene expression patterns in vitro and histological evaluation in vivo. CONCLUSIONS: Freshly isolated chondrocytes from OA patients could be a source of replacement for articular chondrocytes being commonly used in MACI. Implantation of phenotypically superior OA chondrocytes in collagen I scaffolds at high density could be a promising tool for the treatment of elderly OA patients.

Return to Sport After Arthroscopic Autologous Matrix-Induced Chondrogenesis for Patients With Osteochondral Lesion of the Talus.

OBJECTIVE: To determine the rate of return of patients to sport after arthroscopic autologous matrix-induced chondrogenesis (AT-AMIC) for outcomes 2 years after surgery. DESIGN: Retrospective observational cross-sectional study. SETTING: C.A.S.C.O.-Foot and Ankle Unit, Istituto Ortopedico Galeazzi, Milan, Italy. PATIENTS AND INTERVENTION: Twenty-six consecutive patients, 65.4% male (mean ± SD age: 33.7 ± 11.0 years), that underwent AT-AMIC procedure between 2012 and 2015 were selected retrospectively. From this population, only sporting patients at amateur's level were included. Arthroscopic autologous matrix-induced chondrogenesis was proposed in patients with pain and persistent disability. MAIN OUTCOME MEASURES: All patients were assessed with the American Orthopaedic Foot and Ankle Score (AOFAS), physical component score of the 12-Item Short Form Health Survey (SF-12), Halasi ankle activity score, and University of California, Los Angeles (UCLA) activity scale preoperatively and at 24 months postoperatively. RESULTS: Overall, 80.8% of the patient group returned to the same preinjury sport. The mean follow-up was 42.6 ± 10.9 months (range from 25 to 62 months). Significant differences were observed with reference to AOFAS, SF-12, Halasi, and UCLA scores at the last follow-up in patients who had undergone AT-AMIC (all, P < 0.001). CONCLUSIONS: A high percentage of patients return to their preinjury sport after AT-AMIC surgery.

Type I pig collagen enhances the efficacy of PEDF 34-mer peptide in a mouse model of laser-induced choroidal neovascularization.

BACKGROUND: Pigment epithelium-derived factor (PEDF)-derived 34-mer peptide (PEDF34, Asp44-Asn77) has anti-angiogenic activity but has limitations in clinical application because of an inverted bell-shaped dose-effect relationship and a short half-life. In this study, we attempted to mitigate these problems by mixing PEDF34 with type I collagen. METHODS: The anti-angiogenic activity of the PEDF34/atelocollagen mixture was evaluated by HUVEC tube formation assay and in a laser-induced choroidal neovascular (CNV) mouse model. PEDF34 and/or collagen were administrated using intravitreal injections or eye drops. CNV lesion size was quantified using FITC-dextran-perfused retinal whole mounts. Western blot analysis and inhibitor assays were used to define the action mechanisms of PEDF34 and the mixture. RESULTS: Collagen broadened the effective dose range of PEDF34 in the tube formation assay by > 250 times (from 0.2 to 50 nM). In the CNV model, five intravitreal injections of PEDF34 were required for therapeutic effect, whereas the mixture had a significant therapeutic effect following a single injection. Eye drops of the mixture showed significantly stronger CNV-suppressive effects than drops of PEDF34 alone. The anti-angiogenic activity of PEDF34 might be mediated by inhibition of ERK and JNK activation by VEGF, and collagen potentiated these effects. CONCLUSIONS: Collagen can serve as a carrier and reservoir of PEDF34. PEDF peptide/collagen mixture is easy to prepare than conventional methods for maintaining the therapeutic effect of PEDF peptide.

Extracellular matrix components modulate different stages in ß2-microglobulin amyloid formation.

Amyloid deposition of WT human ß2-microglobulin (WT-hß2m) in the joints of long-term hemodialysis patients is the hallmark of dialysis-related amyloidosis. In vitro, WT-hß2m does not form amyloid fibrils at physiological pH and temperature unless co-solvents or other reagents are added. Therefore, understanding how fibril formation is initiated and maintained in the joint space is important for elucidating WT-hß2m aggregation and dialysis-related amyloidosis onset. Here, we investigated the roles of collagen I and the commonly administered anticoagulant, low-molecular-weight (LMW) heparin, in the initiation and subsequent aggregation phases of WT-hß2m in physiologically relevant conditions. Using thioflavin T fluorescence to study the kinetics of amyloid formation, we analyzed how these two agents affect specific stages of WT-hß2m assembly. Our results revealed that LMW-heparin strongly promotes WT-hß2m fibrillogenesis during all stages of aggregation. However, collagen I affected WT-hß2m amyloid formation in contrasting ways: decreasing the lag time of fibril formation in the presence of LMW-heparin and slowing the rate at higher concentrations. We found that in self-seeded reactions, interaction of collagen I with WT-hß2m amyloid fibrils attenuates surface-mediated growth of WT-hß2m fibrils, demonstrating a key role of secondary nucleation in WT-hß2m amyloid formation. Interestingly, collagen I fibrils did not suppress surface-mediated assembly of WT-hß2m monomers when cross-seeded with fibrils formed from the N-terminally truncated variant ΔN6-hß2m. Together, these results provide detailed insights into how collagen I and LMW-heparin impact different stages in the aggregation of WT-hß2m into amyloid, which lead to dramatic effects on the time course of assembly.

Autologous Matrix-Induced Chondrogenesis: A Systematic Review of the Clinical Evidence.

BACKGROUND: The addition of a type I/III collagen membrane in cartilage defects treated with microfracture has been advocated for cartilage repair, termed "autologous matrix-induced chondrogenesis" (AMIC). PURPOSE: To examine the current clinical evidence regarding AMIC for focal chondral defects. STUDY DESIGN: Systematic review. METHODS: A systematic review was performed by searching PubMed, ScienceDirect, and Cochrane Library databases. Inclusion criteria were clinical studies of AMIC for articular cartilage repair, written in English. Relative data were extracted and critically analyzed. PRISMA guidelines were applied, the methodological quality of the included studies was assessed by the modified Coleman Methodology Score (CMS), and aggregate data were generated. RESULTS: Twenty-eight clinical articles were included: 12 studies (245 patients) of knee cartilage defects, 12 studies (214 patients) of ankle cartilage defects, and 4 studies (308 patients) of hip cartilage defects. The CMS demonstrated a suboptimal study design in the majority of published studies (knee, 57.8; ankle, 55.3; hip, 57.7). For the knee, 1 study reported significant clinical improvements for AMIC compared with microfracture for medium-sized cartilage defects (mean defect size 3.6 cm2) after 5 years (level of evidence, 1). No study compared AMIC with matrix-assisted autologous chondrocyte implantation (ACI) in the knee. For the ankle, no clinical trial was available comparing AMIC versus microfracture or ACI. In the hip, only one analysis (level of evidence, 3) compared AMIC with microfracture for acetabular lesions. For medium-sized acetabular defects, one study (level of evidence, 3) found no significant differences between AMIC and ACI at 5 years. Specific aspects not appropriately discussed in the currently available literature include patient-related factors, membrane fixation, and defect properties. No treatment-related adverse events were reported. CONCLUSION: This systematic review reveals a paucity of high-quality, randomized controlled studies testing the AMIC technique versus established procedures such as microfracture or ACI. Evidence is insufficient to recommend joint-specific indications for AMIC. Additional nonbiased, high-powered, randomized controlled clinical trials will provide better clinical and structural long-term evidence, thus helping to define possible indications for this technique.

First clinical experience with a new injectable recombinant human collagen scaffold combined with autologous platelet-rich plasma for the treatment of lateral epicondylar tendinopathy (tennis elbow).

BACKGROUND: Lateral epicondylitis is a tendinopathy of the common extensor origin at the elbow. When traditional conservative treatment fails, more effective therapies are needed. Vergenix Soft Tissue Repair (STR) Matrix (CollPlant Ltd., Ness-Ziona, Israel) is an injectable gel composed of cross-linked bioengineered recombinant human type I collagen combined with autologous platelet-rich plasma (STR/PRP). The complex forms a collagen-fibrin matrix that promotes cell migration and tissue repair. Based on positive outcomes from preclinical trials, this study is the first clinical trial of STR/PRP on tendinopathy. We hypothesized that STR/PRP would be a safe and effective treatment for lateral epicondylar tendinopathy. METHODS: Patients with chronic lateral epicondylitis underwent treatment with STR/PRP. Outcome assessment included grip strength, functional disability, and changes in sonographic tendon appearance for up to 6 months after treatment. RESULTS: The study enrolled 40 patients. No systemic or local severe adverse events were reported. Clinical evaluation revealed an improvement in the mean Patient-Rated Tennis Elbow Evaluation score from 64.8 before treatment and showed a 59% reduction at 6 months. The 12-Item Short-Form Health Survey questionnaire showed improvement from a mean score of 30.7 to 37.7 at the final follow-up. Grip strength increased from 28.8 kg at baseline to 36.8 kg at 6 months. Improvements in sonographic tendon appearance were evident among 68% of patients. CONCLUSION: STR/PRP is a safe treatment that effectively induces clinically significant improvements in elbow symptoms and general well-being as well as objective measures of strength and imaging of the common extensor tendon within 6 months of treatment of elbow tendinopathy recalcitrant to standard treatments.

Pure type-1 collagen application to third molar extraction socket reduces postoperative pain score and duration and promotes socket bone healing.

BACKGROUND/PURPOSE: Extraction of the third molar may cause post-operative complications. This study assessed whether application of pure type-1 collagen to the third molar extraction socket can reduce post-operative pain score and duration and promote socket bone healing. METHODS: Fourteen patients who underwent 20 bilateral and symmetric third molar extractions were included in this study. After two tooth extractions at two different occasions in the same patient, one socket was filled with pure type-1 collagen (experimental group, n = 20) and the other socket received nothing but the blood clot (control group, n = 20). The post-operative pain score and duration, mouth-opening limitation, and the bone density at the socket site were assessed at weeks 1, 2, 4, and 8 after tooth extraction. RESULTS: Patients in the experimental group had a significantly lower mean post-operative pain score (2.6 ± 1.2) than patients in the control group (4.7 ± 2.0), and had a significantly shorter post-operative pain duration (2.7 ± 1.4 days) than patients in the control group (3.7 ± 1.8 days). We also observed a significantly lower frequency of mouth-opening limitation in 20 experimental-group patients (45%) than in 20 control-group patients (90%, P = 0.007). Moreover, a significantly higher mineralization ratio (10.2%) was found in the experimental socket site than in the control socket site. CONCLUSION: Application of pure type-1 collagen to the third molar extraction socket can reduce post-operative pain score and duration, decrease the frequency of mouth-opening limitation, and increase mineralization ratio at the extraction socket site.

Use of a Biomimetic Scaffold for the Treatment of Osteochondral Lesions in Early Osteoarthritis.

The aim of this study is to investigate clinical and radiographic outcomes of a biomimetic scaffold for the treatment of osteochondral knee lesions in patients with early OA. Study population was represented by 26 patients with a mean age of 44 years affected by early OA. Inclusion criteria were two episodes of knee pain for more than 10 days in the last year, Kellgren-Lawrence OA grade 0 or I or II, and arthroscopic findings of cartilage defects. Nineteen patients had a previous surgery, 11 of which were revision surgeries of osteochondral unit. All patients were treated with a biomimetic scaffold with a tri-layered structure of type I equine collagen and magnesium-enriched hydroxyapatite. Clinical outcomes were evaluated using the IKDC, Lysholm, VAS, KOOS, and Tegner scores at baseline and at an average follow-up of 35 months. Magnetic resonance imaging (MRI) was performed at follow-up time in 19 patients. Clinical outcomes showed significant improvement in VAS, Lysholm, IKDC subjective score, and KOOS subscales in 69% of the patients. Complication rate of this cases series was 11%, with no surgical failure, although 31% of patients did not reach a significant improvement and were thus considered as clinical failure. MRI analysis showed integration of the scaffold only in 47% of the patients, with partial regeneration of the subchondral bone. No correlation between clinics and radiological images was found. The use of a biomimetic osteochondral scaffold in the setting of an early OA, alone or associated with other procedures, appeared to be a valid and safe option, able to provide good and stable clinical outcomes with high patient's satisfaction and low complication rate.

Oral Intake of Low-Molecular-Weight Collagen Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind, Placebo-Controlled Study.

Collagen-peptide supplementation could be an effective remedy to improve hydration, elasticity, and wrinkling in human skin. The aim of this study was to conduct a double-blind, randomized, placebo-controlled trial to clinically evaluate the effect on human skin hydration, wrinkling, and elasticity of Low-molecular-weight Collagen peptide (LMWCP) with a tripetide (Gly-X-Y) content >15% including 3% Gly-Pro-Hyp. Individuals (n = 64) were randomly assigned to receive either placebo or 1000 mg of LMWCP once daily for 12 weeks. Parameters of skin hydration, wrinkling, and elasticity were assessed at baseline and after 6 weeks and 12 weeks. Compared with the placebo group, skin-hydration values were significantly higher in the LMWCP group after 6 weeks and 12 weeks. After 12 weeks in the LMWCP group, visual assessment score and three parameters of skin wrinkling were significantly improved compared with the placebo group. In case of skin elasticity, one parameter out of three was significantly improved in the LMWCP group from the baseline after 12 weeks, while, compared with the placebo group, two parameters out of three in the LMWCP group were higher with significance after 12 weeks. In terms of the safety of LMWCP, none of the subjects presented adverse symptoms related to the test material during the study period. These results suggest that LMWCP can be used as a health functional food ingredient to improve human skin hydration, elasticity, and wrinkling.

Injectable collagen/RGD systems for bone tissue engineering applications.

Imbalance crosslink density and polymer concentration gradient is formed within the traditional alginate hydrogel using calcium chloride as a crosslinking agent in external gelation for instantaneously process. In this studying, type I collagen (Col I) blended calcium salt form of poly(γ-glutamic acid) (γCaPGA) was mixing with RGD-modified alginate with convenient gelation process and suitable for practical use. The hydrophilicity of the resulting hydrogels was evaluated through swelling tests, water retention capacity tests, and water vapor permeation tests. Mineralization was qualitatively evaluated by alizarin red dyeing at day 14, verifying the deposition of calcium. The in vitro osteogenic differentiation is monitored by determining the early and late osteocalcin (OCN) and osteopontin (OPN) markers with MG63 cells. Obtained results demonstrated that no extremely changes in mechanical properties. After 14 days of culture, hydrogels significantly stimulated OCN/OPN gene expressions and MG63 cell proliferation. Unusually, γCaPGA with RGD-modified alginate appeared better calcium deposition in 14 days than the other. However, addition of Col I can counterpoise RGD effect in blood coagulation and platelet adhesion made the hydrogel more flexibility and selectively in use. This studying provided that non-covalently crosslinked hydrogel by γCaPGA with alginate can be upgrading by RGD and Col I in water uptake capability, obviously effective for MG63 cells and are remarkably biocompatible and exhibited no cytotoxicity. Moreover, results also displayed the injectable process without complicated procedure, have high cost/performance ratio and have great potential for bone regeneration.

Matrix-Induced Autologous Chondrocyte Implantation (MACI) Using a Cell-Seeded Collagen Membrane Improves Cartilage Healing in the Equine Model.

BACKGROUND: Autologous chondrocyte implantation (ACI) using a collagen scaffold (matrix-induced ACI; MACI) is a next-generation approach to traditional ACI that provides the benefit of autologous cells and guided tissue regeneration using a biocompatible collagen scaffold. The MACI implant also has inherent advantages including surgical implantation via arthroscopy or miniarthrotomy, the elimination of periosteal harvest, and the use of tissue adhesive in lieu of sutures. This study evaluated the efficacy of the MACI implant in an equine full-thickness cartilage defect model at 1 year. METHODS: Autologous chondrocytes were seeded onto a collagen type-I/III membrane and implanted into one of two 15-mm defects in the femoral trochlear ridge of 24 horses. Control defects either were implanted with cell-free collagen type-I/III membrane (12 horses) or were left ungrafted as empty defects (12 horses). An additional 3 horses had both 15-mm defects remain empty as nonimplanted joints. The repair was scored by second-look arthroscopy (12 weeks), and necropsy examination (53 weeks). Healing was assessed by arthroscopic scoring, gross assessment, histology and immunohistology, cartilage matrix component assay, and gene expression determination. Toxicity was examined by prostaglandin E2 formation in joint fluid, and lymph node morphology combined with histologic screening of organs. RESULTS: MACI-implanted defects had improved gross healing and composite histologic scores, as well as increases in chondrocyte predominance, toluidine blue-stained matrix, and collagen type-II content compared with scaffold-only implanted or empty defects. There was minimal evidence of reaction to the implant in the synovial membrane (minor perivascular cuffing), subchondral bone, or cartilage. There were no adverse clinical effects, signs of organ toxicity, or evidence of chondrocytes or collagen type-I/III membrane in draining lymph nodes. CONCLUSIONS: The MACI implant appeared to improve cartilage healing in a critical-sized defect in the equine model compared with collagen matrix alone. CLINICAL RELEVANCE: These results indicate that the MACI implant is quick to insert, provides chondrocyte security in the defect, and improves cartilage healing compared with ACI.

Sika pilose antler type I collagen promotes BMSC differentiation via the ERK1/2 and p38-MAPK signal pathways.

CONTEXT: Sika pilose antler type I collagen (SPC-I) have been reported to promote bone marrow mesenchymal stem cell (BMSC) proliferation and differentiation. However, the underlying mechanism is still unclear. OBJECTIVE: This study investigates the molecular mechanisms of SPC-I on the BMSC proliferation and differentiation of osteoblast (OB) in vitro. MATERIAL AND METHODS: The primary rat BMSC was cultured and exposed to SPC-I at different concentrations (2.5, 5.0 and 10.0 mg/mL) for 20 days. The effect of SPC-I on the differentiation of BMSCs was evaluated through detecting the activity of alkaline phosphatase (ALP), ALP staining, collagen I (Col-I) content, and calcified nodules. The markers of osteoblastic differentiation were evaluated using RT-PCR and Western-blot analysis. RESULTS: SPC-I treatment (2.5 mg/mL) significantly increased the proliferation of BMSCs (p < 0.01), whereas, SPC-I (5.0 and 10.0 mg/mL) significantly inhibited the proliferation of BMSCs (p < 0.01). SPC-I (2.5 mg/mL) significantly increased ALP activity and Col-I content (p < 0.01), and increased positive cells in ALP staining and the formation of calcified nodules. Additionally, the gene expression of ALP, Col-I, Osteocalcin (OC), Runx2, Osterix (Osx), ERK1/2, BMP2 and p38-MAPK, along with the protein expression of ERK1/2, p-ERK1/2, p-p38 MAPK were markedly increased in the SPC-I (5.0 mg/mL) treatment group (p < 0.01) compared to the control group. DISCUSSION AND CONCLUSIONS: SPC-I can induce BMSC differentiation into OBs and enhance the function of osteogenesis through ERK1/2 and p38-MAPK signal transduction pathways and regulating the gene expression of osteogenesis-specific transcription factors.

Daily oral consumption of hydrolyzed type 1 collagen is chondroprotective and anti-inflammatory in murine posttraumatic osteoarthritis.

Osteoarthritis (OA) is a degenerative joint disease for which there are no disease modifying therapies. Thus, strategies that offer chondroprotective or regenerative capability represent a critical unmet need. Recently, oral consumption of a hydrolyzed type 1 collagen (hCol1) preparation has been reported to reduce pain in human OA and support a positive influence on chondrocyte function. To evaluate the tissue and cellular basis for these effects, we examined the impact of orally administered hCol1 in a model of posttraumatic OA (PTOA). In addition to standard chow, male C57BL/6J mice were provided a daily oral dietary supplement of hCol1 and a meniscal-ligamentous injury was induced on the right knee. At various time points post-injury, hydroxyproline (hProline) assays were performed on blood samples to confirm hCol1 delivery, and joints were harvested for tissue and molecular analyses were performed, including histomorphometry, OARSI and synovial scoring, immunohistochemistry and mRNA expression studies. Confirming ingestion of the supplements, serum hProline levels were elevated in experimental mice administered hCol1. In the hCol1 supplemented mice, chondroprotective effects were observed in injured knee joints, with dose-dependent increases in cartilage area, chondrocyte number and proteoglycan matrix at 3 and 12 weeks post-injury. Preservation of cartilage and increased chondrocyte numbers correlated with reductions in MMP13 protein levels and apoptosis, respectively. Supplemented mice also displayed reduced synovial hyperplasia that paralleled a reduction in Tnf mRNA, suggesting an anti-inflammatory effect. These findings establish that in the context of murine knee PTOA, daily oral consumption of hCol1 is chondroprotective, anti-apoptotic in articular chondrocytes, and anti-inflammatory. While the underlying mechanism driving these effects is yet to be determined, these findings provide the first tissue and cellular level information explaining the already published evidence of symptom relief supported by hCol1 in human knee OA. These results suggest that oral consumption of hCol1 is disease modifying in the context of PTOA.

Murine ultrasound-guided transabdominal para-aortic injections of self-assembling type I collagen oligomers.

Abdominal aortic aneurysms (AAAs) represent a potentially life-threatening condition that predominantly affects the infrarenal aorta. Several preclinical murine models that mimic the human condition have been developed and are now widely used to investigate AAA pathogenesis. Cell- or pharmaceutical-based therapeutics designed to prevent AAA expansion are currently being evaluated with these animal models, but more minimally invasive strategies for delivery could improve their clinical translation. The purpose of this study was to investigate the use of self-assembling type I collagen oligomers as an injectable therapeutic delivery vehicle in mice. Here we show the success and reliability of a para-aortic, ultrasound-guided technique for injecting quickly-polymerizing collagen oligomer solutions into mice to form a collagen-fibril matrix at body temperature. A commonly used infrarenal mouse AAA model was used to determine the target location of these collagen injections. Ultrasound-guided, closed-abdominal injections supported consistent delivery of collagen to the area surrounding the infrarenal abdominal aorta halfway between the right renal artery and aortic trifurcation into the iliac and tail arteries. This minimally invasive approach yielded outcomes similar to open-abdominal injections into the same region. Histological analysis on tissue removed on day 14 post-operatively showed minimal in vivo degradation of the self-assembled fibrillar collagen and the majority of implants experienced minimal inflammation and cell invasion, further confirming this material's potential as a method for delivering therapeutics. Finally, we showed that the typical length and position of this infrarenal AAA model was statistically similar to the length and targeted location of the injected collagen, increasing its feasibility as a localized therapeutic delivery vehicle. Future preclinical and clinical studies are needed to determine if specific therapeutics incorporated into the self-assembling type I collagen matrix described here can be delivered near the aorta and locally limit AAA expansion.