Objective The amniotic carrier complex membrane, which contains bFGF and vitamin C (VitC) and is loaded with BMSCs, is planted into the deeply-partial wounds of rabbits. To explore its influence on the epidermis renascence and regenerating speed in the process of the dermis restore. Methods BMSCs were isolated from the marrows of 24 healthy3-month-old New Zealand rabbits, male or female, weighing 1.0-1.5 kg. The BMSCs were cultured in vitro and purified, and then amniotic carrier complex membrane was prepared, whose size was 4.52 cm2. Three deep-partial wounds, with the area of about 3.14 cm2, were produced on the back of each rabbit. All the wounds were randomly divided into 3 groups: group A, group B and group C. Group A was the experimental group in which the amniotic carrier complex membrane was planted, including 1 ml BMSCs, 10 mL bFGF (0.2 mg/L) and 10 mL VitC (0.02 g/L). In group B, the amniotic carrier complex membrane was planted, including only 1 mL BMSCs. In group C, the amniotic carrier complex membrane alone was planted. After the operation, general observation was conducted. At postoperative 7, 14 and 21 days, respectively, the observation by HE, Masson, Van Giesonr staining and immunohistochemical staining of collagen type I was performed. The ink perfusion method was performed to evaluate the velocity and the qual ity of the wound heal ing after the transplantation. Results All the wounds obtained good heal ing. At 14 days after the operation, the ratio of wound heal ing was 60%, 41% and 23% in groups A, B and C, respectively. At 21 days after the operation, the the ratio of wound heal ing was 99%, 90% and 81% in groups A, B and C, respectively. There were significant differences between any two groups (P lt; 0.05). The depth of the newborn dermis, the number of the active collagen type I mascul ine cells and the number of the blood vessels in group A were better and more than in group B. And those in group B were better and more than in group C. At the exterior area of the newborn dermis, there was lots of regenerated epidermis from the peripheral normal skin, which in group A was better than in group B, and in group B was better than in group C. onclusion The amniotic carrier complex membrane transplanted to deep-partial wounds, which is appended withBMSCs, bFGF and VitC, can accelerate repair and reconstruction of the dermis. There has an optimal time of the renascence and regeneration of the epidermis in the process of dermis repair.
Objective To investigate the effect of bFGF on denervated skeletal muscle in accelerating muscle satell ite cell prol iferation, supplying neurotrophic factors and reducing muscle atrophy. Methods Twenty-eight Wistar male rats weredivided into the experimental group and the control group randomly, whose left lower l imb sciatic nerve was excised to make animal models of denervated skeletal muscle. The sil ia gel tubes containing 0.1 g bFGF and normal sal ine were implanted into gastrocnemius in the experimental and control groups, respectively. After 14 and 30 days of operation, gross appearance was observed; muscle wet weight and potential ampl itude of gastrocnemius fibrillation were measured; histological observation and electron microscope observation were made. Results At 14 and 30 days after operation, gastrocnemius atrophy and adhesion were more obvious in the control group than those in the experimental group. At 30 days after operation, the potential amplitude of gastrocnemius fibrillation and muscle wet weight were experimental group (0.220 6 ± 0.301 0) μm and (2.475 7 ± 0.254 6) g in the experimental group, and (0.155 2 ± 0.050 3) μm and (1.459 1 ± 0.642 5) g in the control group. There was a significant difference between two groups (P lt; 0.05). At 14 and 30 days after operation, HE staining showed more muscle satell ite cell nucleiin gastrocnemius of the experimental group than that of the control group; Mallory staining showed more blue connective tissues in the control group than in the experimental group; PCNA staining showed more PCNA positive cell nuclei in the experimental group than in the control group; and the AgNO3 staining testified more grains of vitamin C and less connective tissue proliferation in the experimental group than in the control group. At 30 days after operation, the fiber diameter and the fiber area were (66.368 6 ± 12.672 7) μm and (2 096.112 9 ± 311.563 9) μm2 in the experimental group, (55.504 0 ± 4.945 0) μm and (1 418.068 0 ± 264.953 7) μm2 in the control group. The PCNA positive cell nuclei number was 116.200 ± 5.357 in the experimental group and 53.000 ± 3.937 in the control group, showing statistically significant difference between the two groups (P lt; 0.05). At 14 and 30 day after operation, ompared with control group, the muscle fiber in the experimental group arrangedly more regularly and had lessatrophy fiber and the connective tissue proliferation. Conclusion bFGF can stimulate the proliferation of muscle satell ite cells in denervated gastrocnemius, delay the muscle fiber atrophy and inhibit connective tissues proliferation in muscle fibers.
Objective To study the outcomes of nerve defect repair with the tissue engineered nerve, which is composed of the complex of SCs, 30% ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeable poly (D, L-lacitic acid) (PDLLA) catheters. Methods SCs were cultured and purified from the sciatic nerves of 1-day-old neonatal SD rats. The 1st passage cells were compounded with bFGF-PLGA sustained release microspheres andECM gel, and then were injected into permeable PDLLA catheters with PLGA microfilaments inside. In this way, the tissueengineered nerve was constructed. Sixty SD rats were included. The model of 15-mm sciatic nerve defects was made, and then the rats were randomly divided into 5 groups, with 12 rats in each. In group A, autograft was adopted. In group B, the blank PDLLA catheters with PBS inside were used. In group C, PDLLA catheters, with PLGA microfilaments and 30% ECM gel inside, were used. In group D, PDLLA catheters, with PLGA microfilaments, SCs and 30% ECM gel inside, were used. In group E, the tissue engineered nerve was appl ied. After the operation, observation was made for general conditions of the rats. The sciatic function index (SFI) analysis was performed at 12, 16, 20 and 24 weeks after the operation, respectively. Eelectrophysiological detection and histological observation were performed at 12 and 24 weeks after the operation, respectively. Results All rats survived to the end of the experiment. At 12 and 16 weeks after the operation, group E was significantly different from group B in SFI (P lt; 0.05). At 20 and 24 weeks after the operation, group E was significantly different from groups B and C in SFI (P lt; 0.05). At 12 weeks after the operation, electrophysiological detection showed nerve conduct velocity (NCV) of group E was bigger than that of groups B and C (P lt; 0.05), and compound ampl itude (AMP) as well as action potential area (AREA） of group E were bigger than those of groups B, C and D (P lt; 0.05). At 24 weeks after the operation, NCV, AMP and AREA of group E were bigger than those of groups B and C (Plt; 0.05). At 12 weeks after the operation, histological observation showed the area of regenerated nerves and the number of myel inated fibers in group E were significantly differents from those in groups A, B and C (Plt; 0.05). The density and diameter of myel inated fibers in group E were smaller than those in group A (Plt; 0.05), but bigger than those in groups B, C and D (P lt; 0.05). At 24 weeks after the operation, the area of regenerative nerves in group E is bigger than those in group B (P lt; 0.05); the number of myel inated fibers in group E was significantly different from those in groups A, B, C (P lt; 0.05); and the density and diameter of myel inated fibers in group E were bigger than those in groups B and C (Plt; 0.05). Conclusion The tissue engineered nerve with the complex of SCs, ECM gel, bFGF-PLGA sustained release microspheres, PLGA microfilaments and permeables PDLLA catheters promote nerve regeneration and has similar effect to autograft in repair of nerve defects.
【Abstract】 Objective To design a novel small-cal iber vascular graft using a decellularized allogeneic vascularscaffold pre-loaded with bFGF. Methods The decellularized canine common carotid were obtained by a detergent-enzymatic procedure, then the scaffolds were covalently l inked with heparin and pre-loaded with bFGF, the amount of binding bFGF and releasing curve were assayed by ELISA. Canine BMSCs expanded in vitro were seed on the scaffolds to observe the effects of binding bFGF on prol iferation. Both bFGF pre-loaded and non-pre-loaded decellularized grafts were implanted in canines as carotid artery interposition for 8 weeks, the patency was examined by digital subtraction angiography and histological method. Results Histology and electron microscopic examination of the decellularized scaffolds showed that cellular components were removed completely and that the extracellular matrix structure remained intact. The amount of binding bFGF positively related to the concentration of bFGF. There was a significant difference in the amount of binding bFGF between two different scaffoldsthroughout all bFGF concentrations(P lt; 0.05), and up to 100 ng/mL, the local and sustained release of bFGF from the heparin treated scaffolds were assayed up to 20 days. Additionally, MTT test showed the bFGF-preloaded scaffolds significantly enhanced the prol iferation of seeded BMSCs in vitro compared with non-bFGF-preloaded scaffolds at 3 days after seeding and thereafter(P lt; 0.01). Furthermore, in vivo canine experiments revealed that all 8 bFGF-pre-loaded scaffolds remained patent after 8 weeks of implantation, and host cell l ined the lumen and populated the wall. Only 1 non-bFGF-pre-loaded scaffold was patent, and the other 7 grafts were occluded because of thrombsus formation. Conclusion This study provides a new strategy to develop a small diameter vascular graft with excellent biocompatibil ity and high patency rate.
Objective To assess the effect of basic fibroblast growth factor (bFGF) and 5-fluorouracil (5-FU) appl ied topically on the tendon adhesion and the heal ing process after the flexor tendon repair in Leghorn chickens. Methods Ninety male Leghorn chickens (weighing 3.0-3.5 kg) were randomly divided into 3 groups, with 30 chickens in each group. The flexordigitorum profundus tendons of the third right toes were transected and sutured directly. The repair site in group A was given 0.6 μL fibrin sealant (FS). In group B, the repair site was given 0.6 μL FS containing 500 ng bFGF. In group C, before the tendons were transected, they had been soaked in 5-FU solution, and then the same treatment as group B was given. Six specimens of the third toe were harvested to perform the macroscopical and histological examinations at 1, 2, 4, and 8 weeks, respectively, and to perform the biomechanical test at 8 weeks. Results All animals survived until the experiment was completed. All incisions healed smoothly. No rupture occurred in the reparied tendon. At 8 weeks, the adhesion degree was l ighter in group C than in group B (P lt; 0.05), but there was no significant difference in the adhesion degree between group A and groups B, C (P gt; 0.05). At 1, 2, and 4 weeks after operation, the number of fibroblast cells of group A was significantly less than that of group B (P lt; 0.05), and the number of fibroblast cells of group C was significantly less than that of group A and group B in the tendon sheath and epitenon (P lt; 0.05); however, it was significantly more than that of group A in the tendon parenchyma (P lt; 0.05), and no significant difference was observed when compared with that of group B (P gt; 0.05). At 8 weeks, no difference was found among 3 groups (P gt; 0.05). The collagen fiber content of group A was significantly less than that of group B at 4 and 8 weeks (P lt; 0.05). In the sheath and epitenon, the collagen fiber content of group A was significantly more than that of group C at 4 weeks (P lt; 0.05); however, no significant difference was found between 2 groups at 8 weeks (P gt; 0.05). The collagen fiber content of group A wassignificantly less than that of group C in the parenchyma at 4 and 8 weeks (P lt; 0.05). At all time points, the collagen fiber content of group B was significantly more than that of group C in the sheath and epitenon (P lt; 0.05), but no significant difference in the parenchyma was observed between 2 groups (P gt; 0.05). The biomechanical tests showed that the gl iding excursion of the tendon in groups A, B, and C was (3.51 ± 0.56), (2.84 ± 0.42), and (4.56 ± 0.59) mm, respectively; the work of flexion was (14.08 ± 1.85), (20.62 ± 3.52), and (10.91 ± 1.53) N.mm, respectively; and the ultimate tensile strength of the tendon was (11.26 ± 1.83), (15.02 ± 2.20), and (14.40 ± 1.57) N, respectively. There were significant differences in the gl iding excursion of the tendon and the work of flexion among 3 groups (P lt; 0.05) and in the ultimate tensile strength of the tendon between group A and groups B, C (P lt; 0.05), but there was no significant difference in the ultimate tensile strength of the tendon between group B and group C (P gt; 0.05). Conclusion Local single-use bFGF and 5-FU can not only effectively promote the heal ing of flexor tendon, but also significantly reduce tendon adhesion.
ObjectiveTo investigate the effect of transforming growth factorβ1 (TGF-β1) and basic fibroblast growth factor 1 (bFGF-1) on the cellular activities, prol iferation, and expressions of ligament-specific mRNA and proteins in bone marrow mesenchymal stem cells (BMSCs) and ligament fibroblasts (LFs) after directly co-cultured. MethodsBMSCs from 3-month-old Sprague Dawley rats were isolated and cultured using intensity gradient centrifugation. LFs were isolated using collagenase. The cells at passage 3 were divided into 6 groups: non-induced BMSCs group (group A), non-induced LFs group (group B), non-induced co-cultured BMSCs and LFs group (group C), induced BMSCs group (group D), induced LFs group (group E), and induced co-cultured BMSCs and LFs group (group F). The cellular activities and prol iferation were examined by inverted contrast microscope and MTT; the concentrations of collagen type Ⅰ and type Ⅲ were determined by ELISA; and mRNA expressions of collagen types I andⅢ, fibronectin, tenascin C, and matrix metalloproteinase 2 (MMP-2) were measured by real-time fluorescent quantitative PCR. ResultsA single cell layer formed in the co-cultured cells under inverted contrast microscope. Group F had fastest cell fusion ( > 90%). The MTT result indicated that group F showed the highest absorbance (A) value, followed by group D, and group B showed the lowest A value at 9 days after culture, showing significant difference (P < 0.05). Moreover, the result of ELISA showed that group F had the highest concentration of collagen type Ⅰ and type Ⅲ (P < 0.05); the concentration of collagen type Ⅲ in group E was significantly higher than that in group D (P < 0.05), but no significant difference was found in the concentration of collagen type Ⅰ between 2 groups (P > 0.05). The ratios of collagen type Ⅰ to type Ⅲ were 1.17, 1.19, 1.10, 1.25, 1.17, and 1.18 in groups A-F; group D was higher than the other groups. The real-time fluorescent quantitative PCR results revealed that the mRNA expressions of collagen type Ⅰ and type Ⅲ and fibronectin were highest in group F; the expression of tenascin C was highest in group D; the expression of MMP-2 was highest in group E; and all differencs were significant (P < 0.05). ConclusionDirectly co-cultured BMSCs and LFs induced by TGF-β1 and bFGF-1 have higher cellular activities, proliferation, and expressions of ligament-specific mRNA and protein, which can be used as a potential source for ligament tissue engineering.
ObjectiveTo study the effects of leukemia inhibitory factor (LIF) and basic fibroblast growth factor (bFGF) on the proliferation and differentiation of human bone marrow mesenchymal stem cells (hBMSCs). MethodshBMSCs at passage 4 were divided into 4 groups according to different culture conditions:cells were treated with complete medium (α-MEM containing 10%FBS, group A), with complete medium containing 10 ng/mL LIF (group B), with complete medium containing 10 ng/mL bFGF (group C), and with complete medium containing 10 ng/mL LIF and 10 ng/mL bFGF (group D). The growth curves of hBMSCs at passage 4 in different groups were assayed by cell counting kit 8; cellular morphologic changes were observed under inverted phase contrast microscope; the surface markers of hBMSCs at passage 8 including CD44, CD90, CD19, and CD34 were detected by flow cytometry. ResultsThe cell growth curves of each group were similar to the S-shape; the cell proliferation rates in 4 groups were in sequence of group D > group C > group B > group A. Obvious senescence and differentiation were observed very early in group A, cells in group B maintained good cellular morphology at the early stage, with slow proliferation and late senescence; a few cells in group C differentiated into nerve-like cells, with quick proliferation; and the cells in group D grew quickly and maintained cellular morphology of hBMSCs. The expressions of CD44 and CD90 in groups A and C at passage 8 cells were lower than those of groups B and D; the expressions of CD19 and CD34 were negative in 4 groups, exhibiting no obvious difference between groups. ConclusionLIF combined with bFGF can not only maintain multiple differentiation potential of hBMSCs, but also promote proliferation of hBMSCs.
ObjectiveTo discuss whether human amniotic mesenchymal stem cells (hAMSCs) possesses the characteristic of mesenchymal stem cells, and could differentiate into ligament cells in vitro after induction. MethodsThe hAMSCs were separated through enzyme digestion, and the phenotypic characteristics of hAMSCs were tested through flow cytometry. The cells at passage 3 were cultured with L-DMEM/F12 medium containing transforming growth factor β1 (TGF-β1)+basic fibroblast growth factor (bFGF) (group A), containing hyaluronic acid (HA) (group B), containing TGF-β1+bFGF+HA (group C), and simple L-DMEM/F12 medium (group D) as control group. The morphology changes of cells in each group were observed by inverted phase contrast microscope at 21 days after induction; the cellular activities and proliferation were examined by sulforhodamine (SRB) colorimetric method; and specific mRNA and protein expressions of ligament including collagen type I, collagen type III, and tenascin C (TNC) were measured by real-time fluorescence quantitative PCR and immunohistochemical staining. ResultsThe flow cytometry result indicated that hAMSCs expressed mesenchymal stem cell phenotype. After 21 days of induction, the cells in groups A, B, and C grew like spindle-shaped fibroblasts under inverted phase contrast microscope, and cells showed single shape, obvious directivity, and compact arrangement in group C. The SRB result indicated that the cells in each group reached the peak of growth curve at 6 days; the cellular activities of groups A, B, and C were significantly higher than that of group D at 6 days after induction. Also, the immunohistochemical staining results showed that no expressions of TNC were detected in 4 groups at 7 days; expressions of collagen type I in groups A, B, and C were significantly higher than that in group D at 7, 14, and 21 days (P<0.001); the expressions of collagen type III in groups A, B, and C were significantly higher than that in group D at 14 and 21 days (P<0.001). There was an increasing tendency with time in collagen type I of group B, in collagen type III and TNC of groups A and C, showing significant difference among different time points (P<0.001). The real-time fluorescence quantitative PCR results revealed that the mRNA expressions of collagen type I and TNC in group C were significantly higher than those in groups A and B (P<0.05), and the mRNA expression of collagen type III in group B were significantly higher than that in groups A and C at 21 days (P<0.05). The mRNA expressions of collagen type I and TNC in groups A and C and mRNA expression of collagen type III in group C had an increasing tendency with time, showing significant difference among different time points (P<0.001). ConclusionThe hAMSCs possesses the characteristics of mesenchymal stem cells and excellent proliferation capacity. After in vitro induction, the expressions of ligament specific genes can be up-regulated and the synthesis of ligament specific proteins can be also strengthened. As a result, it can be used as one of ligament tissue engineering seed cell sources.
Objective To determine the efficacy of D980-nm laser in dissolving fat and renewing skin, and to explore the clinical application of D980-nm laser in reconstruction of photodamaged skin. Methods Eighteen 12-14 month-old male Sprague-Dawley rats, weighing 400-450 g, were randomly divided into 3 groups (n=6). The rat skin at the left side was exposed to D980-nm laser irradiation at a density of 20 J/cm2, a power of 8 W, a pulse width of 20 ms, and a pulse frequency of 40 Hz for 1 time (group A), 2 times of 5-minute interval (group B), and 3 times of 5-minute interval (group C) as a treatment course, for 4 treatment courses with an interval of 1 week; the other side of the skin was not treated as the control groups (groups A1, B1, and C1, respectively). After 8 weeks, the skin was harvested for HE staining and immunohistochemical staining to observe the structure changes of skin, to measure the dermal thickness, to count the number of fibroblasts, and detect the expressions of transforming growth factor β1 (TGF-β1) and basic fibroblast growth factor (bFGF). Results Compared with groups A1, B1, and C1, the skin structure was significantly improved in groups A, B, and C. After D980-nm laser irradiation, the number of fat cells decreased; local angiogenesis was observed; the total number of fibroblasts and fibers increased; the collagen fiber had large diameter, and arranged closely and regularly; the dermal thickness and the number of the fibroblasts increased; and the expressions of TGF-β1 and bFGF were significantly enhanced, showing significant differences (P<0.05). With increased D980-nm laser irradiation times, the above indexes increased, showing significant differences between group C and groups A, B (P<0.05). Conclusion D980-nm laser treatment has lipolytic and tender effect on the skin, and the frequency of the treatment is an important factor in skin renewal.
Objective To evaluate the effect of the local del ivery of basic fibroblast growth factor 2 (bFGF-2) on the osseointegration around titanium implant of diabetic rats. Methods The bFGF-2-loaded poly (lactic-co-glycol ic acid) microspheres were prepared by water/oil/water (W/O/W) double-emulsion solvent evaporation method. Thirty-five male SPF level Sprague Dawley rats, weighing 220-250 g and aged 9 weeks, were selected as experimental animals. Ten rats were fedwith the routine diet as normal control group. The other 25 rats were made the diabetic animal model by giving high fat-sugar diet and a low dose streptozotocin (30 mg/ kg) intravenously; 20 rats were made the diabetic animal model successfully. Then 20 rats were randomly divided into diabetic control group (n=10) and bFGF-2 intervention group (n=10). A hole was drilled in the right tibia bone of all rats, and the titanium implant treated by micro-arc oxidation surface was planted into the hole. Simultaneously, the previously prepared microspheres and blood were mixed and were loaded on the surface of the implant before it was implanted into the rats of the bFGF-2 intervention group. At 4 and 8 weeks, the tibia containing implants was harvested, embedded with resin and made undecalcified tissue sl ices to compare the osseointegration. Results At 4 weeks, the implants of the normal control group were surrounded by new lamellar bone with continuity; whereas the tissue around the implants of the diabetic control group contained l ittle woven bone and some fibrous tissue; and obvious new formed bone with continuity was observed in bFGF-2 intervention group. At 8 weeks, the results of 3 groups were similar to those at 4 weeks. At 4 weeks, the percentage of bone-implant contact (BIC) in diabetic control group was significantly less than those in normal control group (P lt; 0.05) and in bFGF-2 intervention group (P lt; 0.05); the BIC in bFGF-2 intervention group was less than in normal control group, but showing no significant difference (P gt; 0.05). After 8 weeks, the BIC in normal control group and in bFGF-2 intervention group were significantly greater than that in diabetic control group (P lt; 0.05), but there was no significant difference between bFGF-2 intervention group and normal control group (P gt; 0.05). Conclusion Local del ivery of bFGF-2 around titanium implants may improve the osseointegration in diabetic rats.