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Objective To determine the protective role of keratinocyte growth factor 2 (KGF-2) on dextran sodium sulfate (DSS)-induced murine colitis and investigate the mechanism of its effect on intestinal mucosal barrier.Methods A total of 36 male C57BL/c mice were divided into 4 groups:normal control group,DSS model group,model + KGF-2 (5 mg/kg) group and model + KGF-2 (10 mg/kg)group.Groups except the control were added 3.5 ％ DSS in drinking water.Disease activity index (DAD,weight change,colon length loss and histological score were detected to evaluate the protective effect of KGF-2 on colitis.Serum fluorescein isothiocyanate-dextran (FITC-D) permeability were assayed by multiscan spectrum.In order to explore the protective role of KGF-2 on murine intestinal mucosal barrier,ZO-1 and occludin protein concentration were detected by immunohistochemical staining and Western blot.Meanwhile,cytokines including TNF-α,IL-6,IL-10,TGF-1β,IFN-γ and IL-1β in colonictissue were detected by ELISA.Results Compared with DSS-induced colitis model group,10 mg/kg KGF-2 significantly reduced DAI (P =0.021 1),weight loss (P =0.017 6),colon length loss (4.956 ±0.2583 vs.6.289±0.215 7,P =0.001 1),histologicalscore (12.17±1.222 vs.7.000±0.6325,P =0.001 1),and FITC-D permeability (168.5 ± 27.01 vs.14.62 ± 1.812,P =0.004 7) and reversed the downregulation of tight junction (TJ) proteins (ZO-1:0.158 6 ± 0.010 51 vs.0.387 9 ± 0.028 64,P＜0.000 1;occluding:0.300 5 ± 0.026 56 vs.0.445 0 ± 0.056 62,P =0.043 4).Significant decrease of TNF-α (68.93 ± 3.379 vs.40.41 ± 1.576,P＜0.000 1) and increase of IL-6 (3 755 ± 309.8 vs.5 640 ± 418.0,P =0.004 7) and IL-10 (304.0 ± 21.47 vs.521.2 ± 49.40,P =0.002 4) levels were noted in the 10 mg/kg KGF-2 treated mice.The effect of the KGF-2 was dose-dependent.Conclusions KGF-2 could ameliorate DSS-induced colitis and it may be associated with the decrease of the damage of mucosal barrier structure and funcntion by preventing ZO-1 and occludin from downregulating.The protective effect of KGF-2 on intestinal barrier function may also be exerted by inhibition of TNF-α and stimulation of IL-6 and IL-10 secretion.
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Objective To develop chitosan composite keratinocyte growth factor-2 mutant(KGF-2M)temperature-sen-sitive dressing and evaluate its physicochemical properties and dynamic release rule were used.Methods Chitosan, chi-tosan quaternary ammonium salt,β-glycerophosphate and other adjuvant materials to configure different formulations which were compounded with KGF-2M in order to develop temperature-sensitive dressing.Gelling time, temperature,the release rate of KGF-2M and other indicators were measured to analyze the physical and chemical properties of the temperature -sen-sitive dressing.Results Chitosan-KGF-2M composite dressing with temperature-sensitive properties was obtained by opti-mizing the formulation components of chitosan and related adjuvant materials.When the liquid dressing was above 35℃,it could be converted from liquid to solid gelatin within 10 minutes.The compound KGF-2M released from the gel was more than 98%at 4 h,and its bioactivity remained stable.Conclusion The thermo-sensitive gel has the characteristics of good conformability,moisturizing(moisture),isolation,wound healing,and a controlled release effect,which has great potential in wartime for wound repair.
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Objective To observe the effects of keratinocyte growth factor-2 (KGF-2) on the expressions of chemokine FKN and tight junction protein claudin-5 in lung tissue of rats with acute lung injury (ALI). Methods Healthy male Sprague-Dawley (SD) rats were randomly divided into normal saline (NS) control group, ALI model group and KGF-2 pretreatment group, with 10 rats in each group. The rat ALI model was reproduced by injection of 0.01 mL/kg oleic acid into the tail vein, and the rats in NS control group were injected with the same amount of NS. The rats in KGF-2 pretreatment group were instilled with 5 mg/kg KGF-2 in the airway at 72 hours before the model reproduction, and the rats in the NS control group and the ALI model group were instilled with the same amount of NS. The abdominal aortic blood of rats was collected at 8 hours after model reproduction, and then the rats were sacrificed, bronchoalveolar in left lung was lavage, and the bronchoalveolar lavage fluid (BALF) was collected for determination of protein levels in plasma and BALF, and the lung permeability index (LPI) was calculated. The lung tissues were harvested, after hematoxylin-eosin (HE) staining, the histopathological changes were observed under light microscope, and the ALI pathology score (LIS) was calculated. The lung wet/dry weight (W/D) ratio was determined. Immunohistochemistry and Western Blot were used to qualitatively and quantitatively analyze the expressions of FKN and claudin-5 in the lung tissue. The correlation between two variables was analyzed by linear or curve fitting correlation analysis. Results In the ALI model group, the lung tissue was severely damaged, and obvious pathological changes were observed, including thickened alveolar space and inflammatory cell infiltration, and LIS score, lung W/D ratio and LPI were significantly higher than those of the NS control group (LIS: 3.56±0.28 vs. 0.62±0.36, lung W/D ratio: 6.37±0.29 vs. 4.39±0.33, LPI: 3.46±0.69 vs. 0.98±0.17, all P < 0.01). Compared with the NS control group, the positive expression of FKN in the lung tissue of the ALI model group was significantly increased, and the expression level was significantly increased (FKN/GAPDH: 0.97±0.18 vs. 0.62±0.04, P < 0.01); the positive expression of claudin-5 was significantly decreased, and the expression level was significantly decreased (claudin-5/GAPDH: 0.56±0.11 vs. 1.06±0.13, P < 0.01). There was a significant negative correlation between FKN and claudin-5 protein expression (r = -0.817, P = 0.025). After pretreatment with KGF-2, the degree of lung tissue damage was significantly reduced, and the pathological changes were significantly improved, and the LIS score, lung W/D ratio and LPI were significantly lower than those of the ALI model group (LIS: 2.41±0.17 vs. 3.56±0.28, lung W/D ratio: 5.45±0.55 vs. 6.37±0.29, LPI: 2.42±0.19 vs. 3.46±0.69, all P < 0.01). Compared with the ALI model group, the positive expression of FKN in the lung tissue of KGF-2 pretreatment group was significantly decreased, and the expression level was significantly decreased (FKN/GAPDH: 0.79±0.03 vs. 0.97±0.18, P < 0.01); the positive expression of claudin-5 was significantly increased, and the expression level was significantly increased (claudin-5/GAPDH: 0.80±0.05 vs. 0.56±0.11, P < 0.01). There was still a significant negative correlation between FKN and claudin-5 protein expression (r = -0.847, P = 0.012). Conclusion KGF-2 may restore the expression of tight junction protein claudin-5 by down-regulating the expression of chemokine FKN, thereby reducing the damage of blood barrier in ALI.
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Objective@#To investigate the effect of recombinant human keratinocyte growth factor 2 (rhKGF-2) on lung tissue of rabbits with severe smoke inhalation injury.@*Methods@#A total of 120 New Zealand rabbits were divided into 5 groups by random number table after being inflicted with severe smoke inhalation injury, with 24 rats in each group. Rabbits in the simple injury group inhaled air, while rabbits in the injury+phosphate buffer solution (PBS) group inhaled 5 mL PBS once daily for 7 d. Rabbits in injury+1 mg/kg rhKGF-2 group, injury+2 mg/kg rhKGF-2 group, and injury+5 mg/kg rhKGF-2 group received aerosol inhalation of 1 mg/kg, 2 mg/kg, and 5 mg/kg rhKGF-2 (all dissolved in 5 mL PBS) once daily for 7 d, respectively. On treatment day 1, 3, 5, and 7, blood samples were taken from the ear central artery of 6 rabbits in each group. After the blood was taken, the rabbits were sacrificed, and the tracheal carina tissue and lung were collected. Blood pH value, arterial oxygen partial pressure (PaO2), arterial blood carbon dioxide pressure (PaCO2), and bicarbonate ion were detected by handheld blood analyzer. The expressions of pulmonary surfactant-associated protein A (SP-A) and vascular endothelial growth factor (VEGF) in lung tissue were detected by Western blotting. Pathomorphology of lung tissue and trachea was observed by hematoxylin-eosin staining. Data were processed with analysis of variance of two-way factorial design and Tukey test.@*Results@#(1) Compared with those in simple injury group, the blood pH values of rabbits in the latter groups on treatment day 1-7 had no obvious change (P>0.05). The PaO2 of rabbits in injury+2 mg/kg rhKGF-2 group on treatment day 5 and 7 were (75.0±2.4) and (71.0±4.5) mmHg (1 mmHg=0.133 kPa), respectively, which were significantly higher than (62.0±6.8) and (63.0±3.0) mmHg in simple injury group (q=4.265, 8.202, P<0.05 or P<0.01). The PaO2 of rabbits in injury+5 mg/kg rhKGF-2 group on treatment day 7 was (82.0±4.9) mmHg, which was significantly higher than that in simple injury group (q=6.234, P<0.01). Compared with that in simple injury group, the PaCO2 of rabbits in injury+2 mg/kg rhKGF-2 group on treatment day 3 was significantly decreased (q=4.876, P<0.01) and significantly increased on treatment day 5 (q=5.562, P<0.01); the PaCO2 of rabbits in injury+5 mg/kg rhKGF-2 group was significantly increased on treatment day 5 and 7 (q=5.013, 4.601, P<0.05 or P<0.01). Compared with that in simple injury group, the serum bicarbonate ion of rabbits in injury+1 mg/kg rhKGF-2 group on treatment day 7 was significantly increased (q=5.142, P<0.01); the serum bicarbonate ion of rabbits in injury+2 mg/kg rhKGF-2 group on treatment day 5 and 7 were significantly increased (q=4.830, 6.934, P<0.01); the serum bicarbonate ion of rabbits in injury+5 mg/kg rhKGF-2 group on treatment day 5 were significantly increased (q=3.973, P<0.05). (2) The expressions of SP-A in lung tissue of rabbits in simple injury group and injury+PBS group in each treatment time point were close (P>0.05). The expressions of SP-A in lung tissue of rabbits in injury+2 mg/kg rhKGF-2 group and injury+5 mg/kg rhKGF-2 group on treatment day 3 were 0.091±0.007 and 0.101±0.009, respectively, significantly higher than 0.069±0.009 in simple injury group (q=10.800, 13.580, P<0.01). The expressions of SP-A in lung tissue of rabbits in injury+1 mg/kg rhKGF-2 group, injury+2 mg/kg rhKGF-2 group, and injury+5 mg/kg rhKGF-2 group on treatment day 5 and 7 were 0.127±0.008, 0.132±0.006, 0.194±0.006, 0.152±0.017, 0.166±0.004, 0.240±0.008, significantly higher than 0.092±0.003 and 0.108±0.005 in simple injury group (q=6.789, 12.340, 17.900, 9.875, 31.480, 40.740, P<0.01). (3) On treatment day 1 and 5, there was no significant difference in the expression of VEGF in lung tissue of rabbits among the 5 groups (P>0.05). Compared with those in simple injury group, the expressions of VEGF in lung tissue of rabbits in injury+2 mg/kg rhKGF-2 group on treatment day 3 and 7 were significantly increased (q=4.243, 8.000, P<0.05 or P<0.01), and the expression of VEGF in lung tissue of rabbits in injury+5 mg/kg rhKGF-2 group on treatment day 7 was significantly increased (q=20.720, P<0.01). (4) On treatment day 1, the injury of rabbits in each group was similar, with a large number of neutrophils infiltrated and abscess formed in the alveolar and interstitial tissue, thickened alveolar septum, some collapsed alveolar and atelectasis; large area of tracheal mucosa was degenerated and necrotic, with a large amount of inflammatory exudates blocking in the cavity. On treatment day 3, the inflammation of lung tissue and trachea in each group were improved, but the inflammation in simple injury group and injury+PBS group was also serious. On treatment day 5, the inflammation in lung tissue and trachea of rabbits in injury+2 mg/kg rhKGF-2 group and injury+5 mg/kg rhKGF-2 group were improved much obviously than those in the other groups. On treatment day 7, the inflammation in lung tissue of rabbits in injury+5 mg/kg rhKGF-2 group alleviated obviously than those in the other groups, most alveoli had no obvious exudative fluid, the alveolar cavity was intact and clear, the local alveolar dilated like a cyst, and the alveolar septum thinning; the improvement of inflammation of trachea was more obvious than the other groups, the tracheal mucosa tended to be more complete, and few neutrophils were infiltrated in the endotracheal cavity.@*Conclusions@#Atomization inhalation of rhKGF-2 can improve the PaO2 level of rabbits with severe smoke inhalation injury, reduce airway inflammation, increase the expression of SP-A and VEGF in lung tissue, thus promoting the repair of lung tissue.
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Objective To establish a method for the determination of active ingredient in recombinant human keratinocyte growth factor 2(rhKGF-2) in the liniment which matrix was mainly constituted by chitin,and to provide a feasible mensuration for quality control.Methods Based on the differential nature of antibody of rhKGF-2,ELISA was established to determine the content of rhKGF-2 in the liniment,and was confirmed by methodology.Results It was proved that other ingredients in the preparation did not disturb the mensuration of rhKGF-2;the calibration curve was linear over the range of 0～9?g?mL~(-1),the regression coefficient was 0.97,the limit of detection was 0.56?g?mL~(-1);the repeat experimentation CV% was 2.0%,and the intermediate precision CV% was(1.01%);the average recovery was 99.1%.Mensurating three batches of trial manufactures,average content for 1.62?g?mL~(-1).Conclusion This method was simple,accurate and could be used in determination of the rhKGF-2 content in this preparation.