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.

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.

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.

Ingestion of bioactive collagen hydrolysates enhance facial skin moisture and elasticity and reduce facial ageing signs in a randomised double-blind placebo-controlled clinical study.

BACKGROUND: Several human studies have demonstrated occurrence of two major collagen peptides, prolyl-hydroxyproline (Pro-Hyp) and hydroxyprolyl-glycine (Hyp-Gly), in human peripheral blood. Some in vitro studies have demonstrated that Pro-Hyp and Hyp-Gly exert chemotaxis on dermal fibroblasts and enhance cell proliferation. Additionally, Pro-Hyp enhances the production of hyaluronic acid by dermal fibroblasts. These findings suggest that the amounts of Pro-Hyp and Hyp-Gly in blood are important factors to show the efficacy of collagen hydrolysates on skin health. RESULTS: We conducted a randomised double-blind placebo-controlled clinical trial of ingestion of two types of collagen hydrolysates, which are composed of different amounts of the bioactive dipeptides Pro-Hyp and Hyp-Gly, to investigate their effects on the improvement of skin conditions. Improvement in skin conditions, such as skin moisture, elasticity, wrinkles, and roughness, were compared with a placebo group at baseline, and 4 and 8 weeks after the start of the trial. In addition, the safety of dietary supplementation with these peptides was evaluated by blood test. Collagen hydrolysate with a higher content of bioactive collagen peptides (H-CP) showed significant and more improvement than the collagen hydrolysate with a lower content of bioactive collagen peptides (L-CP) and the placebo, in facial skin moisture, elasticity (R2), wrinkles and roughness, compared with the placebo group. In addition, there were no adverse events during the trial. CONCLUSION: This study demonstrated that the use of the collagen hydrolysate with a higher content of Pro-Hyp and Hyp-Gly led to more improvement in facial skin conditions, including facial skin moisture, elasticity, wrinkles and roughness. © 2016 Society of Chemical Industry.

Preclinical evaluation of collagen type I scaffolds, including gelatin-collagen microparticles and loaded with a hydroglycolic Calendula officinalis extract in a lagomorph model of full-thickness skin wound.

Previously, we have developed collagen type I scaffolds including microparticles of gelatin-collagen type I (SGC) that are able to control the release of a hydroglycolic extract of the Calendula officinalis flower. The main goal of the present work was to carry out the preclinical evaluation of SGC alone or loaded with the C. officinalis extract (SGC-E) in a lagomorph model of full-thickness skin wound. A total of 39 rabbits were distributed in three groups, of 13 animals each. The first group was used to compare wound healing by secondary intention (control) with wound healing observed when wounds were grafted with SGC alone. Comparison of control wounds with wounds grafted with SGC-E was performed in the second group, and comparison of wounds grafted with SGC with wounds grafted with SGC-E was performed in the third group. Clinical follow-ups were carried in all animals after surgery, and histological and histomorphometric analyses were performed on tissues taken from the healed area and healthy surrounding tissue. Histological and histomorphometric results indicate that grafting of SGC alone favors wound healing and brings a better clinical outcome than grafting SGC-E. In vitro collagenase digestion data suggested that the association of the C. officinalis extract to SGC increased the SGC-E cross-linking, making it difficult to degrade and affecting its biocompatibility.

Co-analgesic therapy for arthroscopic supraspinatus tendon repair pain using a dietary supplement containing Boswellia serrata and Curcuma longa: a prospective randomized placebo-controlled study.

BACKGROUND: The cuff tendon that is most prone to full-thickness rotator cuff tears is the supraspinatus (SSP). Arthroscopic SSP repair ensures good to satisfactory mid- to long-term clinical outcomes. However, the intense postoperative pain reduces rehabilitation compliance and is cause of patient dissatisfaction. Many natural compounds act by inhibiting inflammatory pathways in a similar way to anti-inflammatory drugs MATERIALS AND METHODS: This was a prospective randomized trial designed to assess the analgesic effect of a dietary supplement (DS) containing Boswellia serrata and Curcuma longa in a population of subjects with full-thickness SSP tendon tear treated by arthroscopy. Three weeks before surgery, patients were randomized to receive Tendisulfur(®) (group T) or a placebo (group P) for 2 months. The primary outcome measure was subjective VAS pain. Secondary outcomes measures were Constant-Murley score simple shoulder test, and patient global assessment (PGA) scores. Patients were assessed immediately at baseline and subsequently at 1, 2, 4, 6, 8, 12, and 24 weeks. RESULTS: Stratification of pain scores and subscores demonstrated significantly lower overall pain scores in group T versus group P at 1 week (p = 0.0477), and lower but not significantly different scores on week 2 (p = 0.0988); at subsequent time points, differences were not significant (p > 0.05). PGA scores were good in all subjects. CONCLUSIONS: In conclusion, this study provides objective data on the effect of a DS containing natural substances, added to standard analgesics, on postoperative RC pain. DS alleviated short and partially mid-term pain, while long-term pain was unchanged. This limitation can probably be addressed by a dosage increase over the first 4 weeks and by extending treatment by 1 or 2 months.

Collagen-based silver nanoparticles for biological applications: synthesis and characterization.

BACKGROUND: Type I collagen is an abundant natural polymer with several applications in medicine as matrix to regenerate tissues. Silver nanoparticles is an important nanotechnology material with many utilities in some areas such as medicine, biology and chemistry. The present study focused on the synthesis of silver nanoparticles (AgNPs) stabilized with type I collagen (AgNPcol) to build a nanomaterial with biological utility. Three formulations of AgNPcol were physicochemical characterized, antibacterial activity in vitro and cell viability assays were analyzed. AgNPcol was characterized by means of the following: ultraviolet-visible spectroscopy, dynamic light scattering analysis, Fourier transform infrared spectroscopy, atomic absorption analysis, transmission electron microscopy and of X-ray diffraction analysis. RESULTS: All AgNPcol showed spherical and positive zeta potential. The AgNPcol at a molar ratio of 1:6 showed better characteristics, smaller hydrodynamic diameter (64.34 ± 16.05) and polydispersity index (0.40 ± 0.05), and higher absorbance and silver reduction efficiency (0.645 mM), when compared with the particles prepared in other mixing ratios. Furthermore, these particles showed antimicrobial activity against both Staphylococcus aureus and Escherichia coli and no toxicity to the cells at the examined concentrations. CONCLUSIONS: The resulted particles exhibited favorable characteristics, including the spherical shape, diameter between 64.34 nm and 81.76 nm, positive zeta potential, antibacterial activity, and non-toxicity to the tested cells (OSCC).

Local application of gentamicin-containing collagen implant in the prophylaxis and treatment of surgical site infection following vascular surgery.

BACKGROUND: The development of surgical site infection (SSI) following vascular surgery is an important issue for healthcare providers as it has serious implications for both patient morbidity and mortality. METHODS: Five publications were identified using the PubMed online database and search terms 'gentamicin-containing collagen implant' plus 'surgical site infection', 'wound infection' and 'vascular surgery'. RESULTS: The reviewed publications demonstrated that prophylactic use of GCCI in conjunction with standard treatment reduces the SSI rate in patients operated on for femeropopliteal bypass grafting. The prophylactic use of GCCI may also have a role to play in patients at high-risk of infection (e.g. in those with co-morbidities such as obesity) and in high-risk procedures (e.g. surgical revision to correct anastomotic aneurysm or dehiscence). GCCI in conjunction with systemic antibiotics may also be effective in the treatment of wound infections of the groin following vascular reconstruction. CONCLUSION: This review demonstrates that GCCI have a role to play in preventing and treating SSI following vascular reconstruction when used in conjunction with standard treatment approaches. Additional randomised, controlled studies are required to further establish the efficacy and cost-effectiveness of GCCI in vascular surgery.

Local application of gentamicin-containing collagen implant in the prophylaxis and treatment of surgical site infection following cardiac surgery.

BACKGROUND: For the cardiac surgeon and patient the development of sternal wound infection is a serious post-operative complication associated with increased risk of death and also considerable morbidity. METHODS: Nine publications were identified using the PubMed online database and search terms 'gentamicin-containing collagen implant' plus 'surgical site infection', 'wound infection' and 'cardiac surgery'. RESULTS: Six out of eight studies demonstrated that prophylactic use of gentamicin-containing collagen implants (GCCI) significantly reduce the wound infection rate following cardiac surgery (via sternotomy) compared to standard treatment alone. The adjunctive use of GCCI is particularly beneficial in high-risk subjects e.g. diabetes and obese patients. GCCI significantly improve the morbidity associated with SSI following cardiac surgery by shortening the recovery phase and length of hospital stay; reducing the need for surgical revision and use of antibiotics. GCCI have been shown to be cost saving across a wide spectrum of patients. A further study has shown that GCCI may also have a therapeutic role to play in patients with deep sternal wounds. CONCLUSION: This review demonstrates that when used dry prior to insertion GCCI can be effective in reducing the rate of SSI following cardiac surgery. GCCI have also been shown to be cost saving as they reduce the substantial morbidity associated with deep SSI. The adjunctive use of GCCI is particularly beneficial in high-risk patients. GCCI may also have a role to play in the treatment of deep sternal wound infection.

Intraperitoneal administration of single dose type I collagen or low dose melatonin to prevent intraperitoneal adhesion formation: a comparative study.

OBJECTIVE: To compare the prevention of adhesion formation by type I collagen or melatonin solutions in the rat model. STUDY DESIGN: A total of 40 female Wistar albino rats were randomly assigned to four groups-type I collagen, melatonin, vehicle control and sham groups. Following midline laparotomy, a standard injury was made on the right uterine horn using bipolar cautery. The animals in the sham group underwent midline laparatomy only. One milliliter of type I collagen, melatonin or vehicle control was instilled onto the injured area immediately before abdominal closure. Fourteen days after the surgery, the type and extent of adhesion formation as well as the uterine horn tissue superoxide dismutase (SOD) and catalase (CAT) activity, and malondialdehyde (MDA) levels were measured. RESULTS: Both the type and extent of adhesion formation were significantly lower in the type I collagen and melatonin groups compared to the control group. The tissue SOD and CAT activity was significantly higher, and MDA levels were significantly lower in the type I collagen and melatonin groups compared to the control group. CONCLUSION: Intraperitoneal administration of type I collagen or low dose melatonin solution onto the injured areas may be an attractive adjuvant to reduce postoperative adhesion formation.

Delivery of recombinant human bone morphogenetic protein-2 using a compression-resistant matrix in posterolateral spine fusion in the rabbit and in the non-human primate.

STUDY DESIGN: A rabbit and rhesus monkey model of posterolateral intertransverse process spine arthrodesis was used. OBJECTIVE: To test two new soft tissue compression resistant ceramic/collagen sponge carriers for recombinant human bone morphogenetic protein-2. SUMMARY OF BACKGROUND DATA: After determining that a plain collagen sponge was too compressible for large animals in a posterolateral fusion application, the authors demonstrated good bone induction using biphasic ceramic phosphate granules (60% hydroxyapatite/40% tricalcium phosphate) as the carrier matrix for recombinant human bone morphogenetic protein 2 in rhesus monkeys. A limitation of 60:40 biphasic ceramic phosphate was its slow resorption time caused by the high hydroxyapatite content, making radiographic detection of new bone formation very difficult. METHODS: Adult New Zealand white rabbits (n = 14) underwent posterolateral spine arthrodesis at L5-L6 using 5:95 biphasic ceramic phosphate (5% hydroxyapatite/95% tricalcium phosphate) impregnated Type I collagen sponges (17 x 35 x 2.5 mm, two per side) loaded with 0.86 mg recombinant human bone morphogenetic protein 2. Additional rabbits (n = 14) received 60:40 hydroxyapatite-tricalcium phosphate granules as the carrier for bone morphogenetic protein 2. Adult rhesus monkeys (n = 6) underwent posterolateral arthrodesis at L4-L5 with ceramic/collagen sponge carrier loaded with 9 mg recombinant human bone morphogenetic protein 2 per side. Two monkeys received ceramic/collagen sponges containing 15:85 biphasic ceramic phosphate (15% hydroxyapatite/85% tricalcium phosphate) with two pieces per side; two received sponges containing 5:95 biphasic ceramic phosphate with two pieces per side, and two received sponges containing 5:95 biphasic ceramic phosphate with four pieces per side. The rabbits were killed after 5 weeks and the monkeys after 24 weeks; the spines were evaluated by manual palpation, radiographs, tensile mechanical testing (rabbits only), and histology. RESULTS: The recombinant human bone morphogenetic protein 2 delivered in the 5:95 biphasic ceramic phosphate/collagen sponge achieved fusion in 100% of rabbits and had improved handling properties compared with the biphasic ceramic phosphate granules. Biomechanical results with 5:95 biphasic ceramic phosphate/collagen carrier were comparable to those obtained with the 60:40 biphasic ceramic phosphate granules and superior to those of autogenous bone graft (P < 0.05). The recombinant human bone morphogenetic protein 2 delivered in the 15:85 or the 5:95 biphasic ceramic phosphate/collagen sponge carrier (two pieces per side) induced fusion in nonhuman primates with normal bone histology, less residual ceramic, and more bone in the center of the carrier matrix in comparison with BCO granules alone. The 15:85 biphasic ceramic phosphate/collagen sponge resulted in fusion mass sizes closer to the original size of the matrix implanted than did the 5:95 biphasic ceramic phosphate/collagen sponge, which was considered a desirable feature. The monkeys with 9 mg recombinant human bone morphogenetic protein 2 spread over four sponges per side instead of two had half the effective recombinant human bone morphogenetic protein 2 concentration per sponge and inferior results. CONCLUSIONS: The new compression-resistant biphasic ceramic phosphate/collagen sponge matrices were biologically compatible with recombinant human bone morphogenetic protein 2 bone formation, resulted in biomechanically stiffer fusion masses than autograft, better space maintenance than plain collagen sponges, and improved handling and radiographic resorption properties over the ceramic carriers previously tested.