OBJECTIVETo observe the efficacy of fenofibrate for hepatic steatosis in rats after severe burn.

METHODSTwenty-seven male SD rats were divided into sham injury group, burn group, and burn+ fenofibrate group according to the random number table, with 9 rats in each group. Rats in sham injury group were sham injured on the back by immersing in 37 ℃ warm water for 15 s and then remained without other treatment. Rats in burn group and burn+ fenofibrate group were inflicted with 30% total body surface area full-thickness scald (hereinafter referred to as burn) on the back by immersing in 98 ℃ hot water for 15 s, and then they were intraperitoneally injected with lactated Ringer's solution at post injury hour (PIH) 1. From PIH 24 to post injury day (PID) 8, rats in burn+ fenofibrate group were treated with fenofibrate in the dose of 80 mg·kg(-1)·d(-1), while those in burn group were treated with equivalent volume of saline. (1) Three rats of each group were respectively selected on PID 4, 6, and 8 for the collection of inferior vena caval blood samples. Serum content of total cholesterol (TC), triglyceride (TG), free fatty acid (FFA), high density lipoprotein (HDL), and low density lipoprotein (LDL) was determined with fully automatic biochemical analyzer. Body mass of each rat was measured immediately after blood sampling, and then rats were sacrificed to collect liver tissue for weighing wet mass. The ratio of wet mass of liver tissue to body mass (liver index) was calculated. Meanwhile, gross observation of liver was performed. (2) One liver tissue sample was harvested from each rat at each time point to observe histopathologic changes with HE staining. One liver tissue slice of each rat at each time point was collected to evaluate degree of hepatic steatosis, and the number of rats in each group in each grade of hepatic steatosis was recorded. Measurement data were processed with analysis of variance of factorial design and SNK test, and enumeration data were processed with Kruskal-Wallis test and Nemenyi test.

RESULTS(1) The content of TC, TG, FFA, and HDL of rats in burn group on PID 4 was obviously different from that in sham injury group (with P values below 0.05). Compared with that in burn group, the content of TC, TG, and FFA of rats was significantly decreased (with P values below 0.05), while the content of HDL of rats was not obviously changed in burn+ fenofibrate group on PID 4 (P>0.05). There were no obvious differences in the content of LDL of rats among 3 groups on PID 4 (with P values above 0.05). The content of TC, TG, and HDL of rats in burn group on PID 6 was obviously different from that in sham injury group (with P values below 0.05). Compared with that in burn group, the content of TC and TG of rats was significantly decreased (with P values below 0.05), while the content of HDL of rats was significantly increased in burn+ fenofibrate group on PID 6 (P<0.05). There were no obvious differences in the content of FFA and LDL of rats among 3 groups on PID 6 (with P values above 0.05). The content of TC and HDL of rats in burn group on PID 8 was obviously different from that in sham injury group (with P values below 0.05). Compared with that in burn group, the content of TC of rats was significantly decreased (P<0.05), while the content of HDL of rats was not obviously changed in burn+ fenofibrate group on PID 8 (P>0.05). There were no obvious differences in content of TG, FFA, and LDL of rats among 3 groups on PID 8 (with P values above 0.05). (2) The texture of liver tissue of rats in burn+ fenofibrate group at each time point was tender and soft, without oil or fat on the section, which was close to the gross condition of liver of rats in sham injury group. Dark yellow plaque scattered on the surface of liver tissue of rats in burn group at each time point with oil and fat on the section, which was especially obvious on PID 6. There was no obvious difference in liver index of rats among 3 groups on PID 4 (F=1.63, P>0.05). On PID 6 and 8, the liver indexes of rats in sham injury group, burn group, and burn+ fenofibrate group were 0.0416±0.0016, 0.0533±0.0054, and 0.0370±0.0069; 0.0423±0.0034, 0.0624±0.0005, and 0.0444±0.0042 respectively. The liver indexes of rats in burn group on PID 6 and 8 were significantly higher than those in the other two groups (with P values below 0.05). There were no obvious differences in the liver indexes of rats between burn+ fenofibrate group and sham injury group on PID 6 and 8 (with P values above 0.05). (3) The liver tissue structure of rats in sham injury group was normal at each time point. Hepatic steatosis of rats in burn group at each time point appeared microvesicular and disperse, which was especially obvious on PID 6. Mild hepatic steatosis was observed in rats of burn+ fenofibrate group on PID 4, and then the structure of liver tissue gradually recovered to normal level from PID 6 on. The degree of hepatic steatosis of rats in sham injury group was 0 grade. One rat in I grade, 1 rat in II grade, and 7 rats in III grade were observed in hepatic steatosis of rats in burn group. Three rats in 0 grade, 4 rats in I grade, and 2 rats in II grade were observed in hepatic steatosis of rats in burn+ fenofibrate group. The degree of hepatic steatosis of rats in burn group was more severe than that in the other two groups (with χ(2) values respectively 56.25 and 162.44, P values below 0.05). The degree of hepatic steatosis of rats in burn+ fenofibrate group was more severe than that in sham injury group (χ(2)=27.51, P<0.05).

CONCLUSIONSFenofibrate can ameliorate the dyslipidemia of severely burned rat, and it can alleviate the degree of hepatic steatosis in certain degree.

Animals ; Burns ; pathology ; Cholesterol, HDL ; blood ; Cholesterol, LDL ; blood ; Dyslipidemias ; drug therapy ; Fatty Acids ; blood ; Fenofibrate ; pharmacology ; Liver ; pathology ; Liver Cirrhosis ; drug therapy ; Male ; Rats ; Rats, Sprague-Dawley ; Triglycerides ; blood

OBJECTIVETo retrospectively analyze the risk factors and clinical manifestations of myocardial damage of patients with severe burn in order to provide evidence for its prevention and treatment.

METHODSTwo hundred and fifty-two patients with severe burn admitted to 5 burn centers from January 2010 to June 2015, conforming to the study criteria, were treated in accordance with the fluid resuscitation formula of the Third Military Medical University. According to the creatine kinase isoenzyme-MB (CK-MB) level before treatment on admission, patients were divided into non-myocardial damage group (n=118, CK-MB level less than 75 U/mL) and myocardial damage group (n=134, CK-MB level higher than or equal to 75 U/mL). Data of patients in two groups were collected and evaluated such as gender, age, body mass, number of patients with chemical burn, admission time after injury, total burn area, full-thickness burn area, number of patients with inhalation injury, levels of haemoglobin, hematocrit, and blood lactate on admission and at post injury hour (PIH) 24 and 48, volumes of urine output and fluid input at PIH 24 and 48, levels of creatinine, urea nitrogen, total bile acid, diamine oxidase on admission and at PIH 24 and 48, and mortality. Furthermore, patients were divided into three groups, i. e. less than 50% total body surface area (TBSA) group (n=110), larger than or equal to 50% TBSA and less than 80% TBSA group (n=83), and larger than or equal to 80% TBSA group (n=59) according to the total burn area, and the incidence rates of myocardial damage in patients of three groups were recorded. Data were processed with chi-square test, t test, Wilcoxon test, analysis of variance for repeated measurement, and the values of P were adjusted by Bonferroni. Basic data of 252 patients were processed with binary logistic regression analysis. Receiver operating characteristic curve of total burn area of 252 patients was drawn to predict myocardial damage.

RESULTS(1) There were no statistically significant differences in age, body mass, number of patients with chemical burn, number of patients with inhalation injury, and full-thickness burn area between two groups (with t values respectively 0.20 and 0.31, χ(2) values respectively 0.49 and 4.10, Z=1.42, P values above 0.05). There were statistically significant differences in gender, admission time after injury, and total burn area of patients between two groups (χ(2)=5.00, with t values respectively 2.44 and 3.13, P<0.05 or P<0.01). (2) Gender, admission time after injury, and total burn area were independent risk factors related to myocardial damage in the patients (with odds ratios respectively 2.608, 3.620, and 1.030; 95% confidence intervals respectively 1.315-5.175, 1.916-6.839, and 1.011-1.049; P values below 0.01). (3) The incidence rates of myocardial damage of patients in less than 50% TBSA group, larger than or equal to 50% TBSA and less than 80% TBSA group, and larger than or equal to 80% TBSA group were 38.2% (42/110), 54.2% (45/83), and 61.0% (36/59) respectively, and there was statistically significant difference among them (χ(2)=9.46, P<0.05). (4) The total area under receiver operating characteristic curve of total burn area to predict myocardial damage of 252 patients was 0.706 (with 95% confidence interval 0.641-0.772, P<0.01), and 51.5% TBSA was chosen as the optimal threshold value, with sensitivity of 62.6% and specificity of 65.3%. (5) Compared with those in non-myocardial damage group, except the levels of haemoglobin and hematocrit at PIH 48 (with t values respectively -0.76 and -0.61, P values above 0.05), the levels of haemoglobin, hematocrit, and blood lactate of patients in myocardial damage group were significantly increased at each time point (with t values from -2.80 to -2.06, P<0.05 or P<0.01). Compared with those in non-myocardial damage group, the volume of urine output of patients was significantly declined (with t values respectively 2.05 and 3.68, P<0.05 or P<0.01), while the volume of fluid input of patients was not obviously changed in myocardial damage group at PIH 24 and 48 (with t values respectively 1.01 and 1.08, P values above 0.05). (6) Compared with those in non-myocardial damage group, the level of creatinine of patients was significantly increased on admission and at PIH 24 and 48 (with Z values from -2.91 to -1.99, P<0.05 or P<0.01), the level of urea nitrogen of patients was only significantly increased at PIH 24 and 48 (with t values respectively -4.75 and -5.24, P values below 0.01), the level of total bile acid of patients was not obviously changed on admission and at PIH 24 and 48 (with t values from -0.81 to -0.20, P values above 0.05), and the level of diamine oxidase of patients was only significantly increased on admission and PIH 24 in myocardial damage group (with t values respectively -3.97 and -2.02, P<0.05 or P<0.01). (7) Compared with that in myocardial damage group, the mortality of patients in non-myocardial damage group was significantly declined (χ(2)=5.81, P<0.05).

CONCLUSIONSPatients with severe burn have high incidence of myocardial damage, which may be predicted by total burn area. Severely burned patients with myocardial damage are more likely to suffer from decline of effective circulating volume, tissue oxygenation disorders, and damage in other organs in shock stage.

Body Surface Area ; Burn Units ; Burns ; pathology ; Fluid Therapy ; Hematocrit ; Hemoglobins ; analysis ; Humans ; Lactic Acid ; blood ; Myocardium ; pathology ; Retrospective Studies ; Shock

BACKGROUND: Major burn injuries induce inflammatory responses and changes in the levels of various cytokines. This study was conducted to assess early changes in the serum levels of inflammatory cytokines after burn injury, identify cytokines associated with mortality, and characterize correlations among cytokines. METHODS: Blood samples of 67 burn patients were collected on days 1 and 3 after burn injury, and the concentrations of 27 cytokines were measured using the Bio-Plex Suspension Array System (Bio-Rad Laboratories, USA). Blood samples of 25 healthy subjects were used as controls. We analyzed statistical differences in the concentrations of each cytokine between the control and patient groups, between day 1 and day 3, and between survival and nonsurvival groups. Correlations among 27 cytokines were analyzed. RESULTS: Median concentrations of granulocyte colony-stimulating factor (G-CSF), granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin 1 receptor antagonist (IL-1RA), interleukin 6 (IL-6), interleukin 8 (IL-8), interleukin 10 (IL-10), interleukin 15 (IL-15), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein 1beta (MIP-1beta), and vascular endothelial growth factor (VEGF) were significantly higher in burn patients than in controls. IL-1RA, IL-6, and MCP-1 levels were significantly higher in the nonsurvival group than in the survival group on day 1 after burn injury. Correlation analysis of 27 cytokines showed different relationships with one another. Stronger correlations among interferon gamma (IFN-gamma), IL-2, IL-4, IL-7, IL-12p70, and IL-17 were found. CONCLUSIONS: IL-1RA, IL-6, and MCP-1 may be used as prognostic indicators of mortality in burn patients and the increase in cytokine concentrations is induced by interactions within a complex network of cytokine-related pathways.
Adult ; Aged ; Burns/*blood/mortality/*pathology ; Case-Control Studies ; Cytokines/*blood ; Female ; Humans ; Male ; Middle Aged ; Prognosis ; Prospective Studies ; Survival Rate ; Young Adult

BACKGROUND: Burn wounds lack normal barriers that protect against pathogenic bacteria, and burn patients are easily colonized and infected by Staphylococcus aureus. Toxic shock syndrome (TSS) is a rare but fatal disease caused by S. aureus. A lack of detectable antibodies to TSS toxin-1 (TSST-1) in serum indicates susceptibility to TSS. METHODS: A total of 207 patients (169 men and 38 women; median age, 42.5 yr) admitted to a burn center in Korea were enrolled in this study. The serum antibody titer to TSST-1 was measured by sandwich ELISA. S. aureus isolates from the patients' nasal swab culture were tested for TSST-1 toxin production by PCR-based detection of the TSST-1 toxin gene. RESULTS: One hundred seventy-four (84.1%) patients showed positive results for antibody against TSST-1. All patients aged > or =61 yr (n=28) and <26 months (n=7) were positive for the anti-TSST-1 antibody. S. aureus was isolated from 70 patients (33.8%), and 58.6% of the isolates were methicillin resistant. Seventeen patients were colonized with TSST-1-producing S. aureus. The antibody positivity in these 17 carriers was 88.2%, and the positivity in the non-carriers was 83.7%. CONCLUSIONS: Most burn patients had antibody to TSST-1, and nasal colonization with TSST-1-producing S. aureus was associated with positive titers of anti-TSST-1 antibody. Additionally, patients with negative titers of anti-TSST-1 antibody might be susceptible to TSS.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antibodies, Bacterial/*blood ; Bacterial Toxins/genetics/immunology/*metabolism ; Burns/blood/*immunology/*microbiology/pathology ; Child ; Child, Preschool ; Enterotoxins/genetics/immunology/*metabolism ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Infant ; Male ; Middle Aged ; Nasal Cavity/microbiology ; Polymerase Chain Reaction ; Prevalence ; Staphylococcal Infections/epidemiology ; Staphylococcus aureus/isolation & purification/*metabolism ; Superantigens/genetics/immunology/*metabolism ; Young Adult

OBJECTIVETo analyze the development of liver damage and reactivation of hepatitis B virus (HBV) during the treatment of extremely severe burn injury in HBsAg positive patients, in order to provide reference for prevention and treatment of liver damage in patients with HBV infection after extremely severe burn.

METHODSMedical records of 54 HBsAg positive patients after extremely severe burn injury admitted from January 2004 to December 2014 were retrospectively analyzed. Development of liver damage and HBV reactivation of these patients during the treatment were analyzed according to the classification of their gender, results of hepatitis B e antigen (HBeAg) and HBV DNA examinations on admission, and development of sepsis in the process of treatment. Data were processed with chi-square test.

RESULTS(1) The incidence of liver damage in the process of treatment of these patients was 85.2% (46/54). Among all the patients, the proportion of liver damage was 35/38 in male, which was significantly higher than that in female (11/16, χ² = 4.867, P<0.05). Liver damage was found in all of 26 patients who were HBeAg positive on admission, 34 patients who were HBV DNA positive on admission, and 36 patients who developed sepsis in the process of treatment; the proportions were significantly higher than those in patients who were HBeAg negative on admission (20/28), patients who were HBV DNA negative on admission (12/20), and patients who did not develop sepsis in the process of treatment (10/18), with χ² values respectively 11.801, 18.384, and 20.574, P values below 0.01. (2) The incidence of HBV reactivation in these patients was 29.6% (16/54). Among all the patients, the proportion of HBV reactivation was 13/38 in male and 3/16 in female, with no statistically significant difference between them (χ² = 0.656, P>0.05). The proportions of HBV reactivation in patients who were HBeAg positive on admission, patients who were HBV DNA positive on admission, and patients who developed sepsis in the process of treatment were respectively 13/26, 16/34, and 15/36, and they were significantly higher than those in patients who were HBeAg negative on admission (3/28), patients who were HBV DNA negative on admission (0/20), and patients who did not develop sepsis in the process of treatment (1/18), with χ² values respectively 9.979, 18.615, and 5.873, P<0.05 or P<0.01.

CONCLUSIONSPatients who are HBsAg positive, HBeAg positive, HBV DNA positive on admission, and develop sepsis in the process of treatment of extremely severe burn injury are more likely to develop liver damage and HBV reactivation. It is necessary to dynamically monitor the changes in HBV DNA and liver function, in order to identity the reactivation of virus.

Alanine Transaminase ; blood ; Burns ; complications ; drug therapy ; Chemical and Drug Induced Liver Injury ; DNA, Viral ; Female ; Hepatitis Antibodies ; blood ; Hepatitis B ; drug therapy ; epidemiology ; virology ; Hepatitis B Surface Antigens ; blood ; immunology ; Hepatitis B virus ; drug effects ; immunology ; isolation & purification ; Hepatitis B, Chronic ; blood ; pathology ; virology ; Humans ; Incidence ; Liver ; pathology ; Male ; Retrospective Studies

OBJECTIVETo observe the effects of docosahexaenoic acid (DHA) on the expressions of TNF-α, IL-6, and leukotriene B4 (LTB4) in serum and expression of NF-κB in pulmonary tissue of rats with severe scald injury.

METHODSOne hundred and sixty SD rats were divided into sham injury (A), sham injury+DHA (B), scald (C), and scald+DHA (D) groups according to the random number table, with 40 rats in each group. Rats in groups A and B were sham injured, while rats in groups C and D were inflicted with 30% TBSA full-thickness scald on the back. Rats in groups B and D were injected with 0.5 mg/mL DHA solution with the dosage of 1 mL/kg via tail vein 5 minutes post injury, while rats in groups A and C with normal saline solution 1 mL/kg. At post injury hour (PIH) 3, 6, 12, 24, and 48, pulmonary tissue and abdominal aorta blood were collected from 8 rats in each group. The serum levels of TNF-α, IL-6, and LTB4 were determined with ELISA, and the protein expression of NF-κB p65 in pulmonary tissue was determined with Western blotting. Data were processed with analysis of variance of factorial design and LSD-t test.

RESULTS(1) The serum levels of TNF-α and IL-6 of rats in group A were similar to those of group B at each time point (with tTNF-α values from 0.223 to 0.947, tIL-6 values from 0.767 to 2.084, P values above 0.05). Compared with those of group A, the serum levels of TNF-α and IL-6 of rats in groups C and D were significantly higher at each time point (with tTNF-α values from 11.800 to 40.357, tIL-6 values from 10.334 to 39.321, P values below 0.01). The serum levels of TNF-α and IL-6 of rats in group D were significantly lower than those of group C at each time point (with tTNF-α values from -17.643 to -8.331, tIL-6 values from -21.596 to -6.332, P values below 0.01). The serum levels of TNF-α and IL-6 in groups C and D both showed a trend of increase earlier and decrease later, and they peaked at PIH 12, respectively (360.4 ± 13.2), (306.8 ± 7.2) pg/mL and (265.4 ± 12.3), (230.5 ± 2.2) pg/mL. (2) The serum level of LTB4 in group A was similar to that of group B at each time point (with t values from 0.787 to 1.096, P values above 0.05). The serum level of LTB4 was significantly higher in groups C and D than in group A at each time point (with t values from 7.501 to 38.962, P values below 0.01). The serum level of LTB4 in group D was obviously lower than that of group C at each time point (with t values from -19.244 to -2.532, P values below 0.01). The serum level of LTB4 in groups C and D both showed a trend of increase earlier and decrease later, and it peaked at PIH 12, (4.59 ± 0.29) and (2.85 ± 0.32) ng/mL respectively. (3) The protein expression of NF-κB p65 in pulmonary tissue in group A was similar to that of group B at each time point (with t values from 0.847 to 1.256, P values above 0.05). The protein expression of NF-κB p65 was significantly higher in groups C and D than in group A at each time point (with t values from 15.167 to 98.074, P values below 0.01). The protein expression of NF-κB p65 in group D was obviously lower than that of group C at each time point (with t values from -37.190 to -14.415, P values below 0.01). The protein expression of NF-κB p65 in groups C and D both showed a trend of increase earlier and decrease later, and it peaked at PIH 12, respectively 4.46 ± 0.12 and 2.94 ± 0.21.

CONCLUSIONSParenteral supply of DHA to rats with severe scald injury can reduce the levels of TNF-α, IL-6, and LTB4 in serum and decrease the expression of NF-κB in pulmonary tissue, thus alleviating the inflammation response.

Animals ; Blotting, Western ; Burns ; Cytokines ; Docosahexaenoic Acids ; Enzyme-Linked Immunosorbent Assay ; Inflammation ; Interleukin-6 ; blood ; Leukotriene B4 ; blood ; Lung ; metabolism ; pathology ; NF-kappa B ; metabolism ; Rats ; Rats, Sprague-Dawley ; Serum ; Soft Tissue Injuries ; Tumor Necrosis Factor-alpha ; blood ; genetics ; Up-Regulation ; physiology

OBJECTIVETo investigate the effect of seawater exposure on intestinal injury in rabbits with scald burns and explore the mechanisms.

METHODSSixty-three rabbits with scald burns covering 20% total body surface area were randomized equally into scald control group (group A), scald with freshwater exposure group (group B), and scald with seawater exposure group (group C). At 2, 4 and 8 h after scald burns, 7 rabbits from each group were sacrificed for detecting plasma superoxide dismutase (SOD) and lipid peroxide (LPO) levels and intestinal contents of prostaglandins (PGs) and for examining the intestinal pathologies; immunohistochemistry was used to detect the expression of Bax and Bcl-2 proteins in the small intestinal epithelium.

RESULTSThe rabbits in group C showed severer intestinal mucosal and barrier function damages than those in groups A and B. The plasma SOD activity and intestinal PGs contents were significantly lowered in group C than in groups A and B at 2, 4, and 8 h postburn (P<0.01) and reduced as the postburn time extended (P<0.01). In group C, plasma LPO content was the highest among the groups (P<0.01) and increased significantly with the seawater exposure time (P<0.01). The expression of Bax and Bcl-2 in the intestinal mucosal tissues was also the highest in group C (P<0.01) at 4 h and 8 h postburn and increased significantly with time (P<0.01).

CONCLUSIONSeawater exposure exacerbates scald burn-induced intestinal mucosal and barrier function damages in rabbits mainly by aggravating intestinal inflammation and structural damage, as evidenced by decreased intestinal PGs contents and plasma SOD activity, increased plasma PLO content, and enhanced Bax and Bcl-2 protein expressions in the intestinal mucosa.

Animals ; Burns ; pathology ; Intestinal Mucosa ; metabolism ; physiopathology ; Lipid Peroxidation ; Prostaglandins ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rabbits ; Seawater ; adverse effects ; Soft Tissue Injuries ; Superoxide Dismutase ; blood ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo investigate the effects of allogeneic adipose-derived stem cells (ADSCs) of rat on the early neovascularization of autologous fat transplantation.

METHODS(1) Experiment 1. Adipose tissue was collected from both inguinal regions of two SD rats to isolate, culture, and purify ADSCs through collagen enzyme digestion, density gradient centrifugation, and adherence method. The fourth passage of cells were collected for morphologic observation, detection of expressions of surface markers CD34, CD49d, CD106, and CD45 of ADSCs with flow cytometer, identification of adipogenic and osteogenic differentiation, and determination of the cell proliferation ability with thiazolyl blue method. (2) Experiment 2. Another 30 SD rats were divided into allogeneic adipose granule (AG) group (A, n = 6), autologous AG group (B, n = 8), autologous ADSCs+autologous AG group (C, n = 8), and allogeneic ADSCs+autologous AG group (D, n = 8) according to the random number table. The fourth passage of ADSCs were obtained from adipose tissue from one side of inguinal region of SD rats in group C. Adipose tissue obtained from one side of inguinal region of SD rats of the other 3 groups was abandoned. The AG was prepared from another side of inguinal region of SD rats in the 4 groups. The mixture of 0.6 g AG from one rat and 1 mL DMEM/F12 nutrient solution was injected subcutaneously into the back of another rat in group A, and so on. Autologous AG was injected into its own body of the rats in group B. The mixture of 1 mL autologous ADSCs mixture which contains 3.0 × 10⁶ cells per mililitre autologous ADSCs combined with autologous AG was injected into the rats in group C. The mixture of 1 mL allogeneic ADSCs mixture which contains 3.0 × 10⁶ cells per mililitre ADSCs extractived from the former 2 rats in experiment 1 combined with autologous AG was injected into the rats in group D. At 7 days post transplantation, fat transplants were harvested for gross observation, measurement of wet weight, pathological observation, and assessment of cells with positive expression of CD31 with immunohistochemical method. Data were processed with one-way analysis of variance and SNK test.

RESULTS(1) The fourth passage of cells proliferated well showing fusiform shape similar to fibroblasts. These cells showed positive expression of CD34 and CD49d and weak positive expression of CD106 and CD45. They were able to differentiate into adipocytes and osteoblasts. These cells were identified as ADSCs. The fourth passage of cells grew faster than that of the tenth passage. (2) At 7 days post transplantation, no liquifying necrosis or infection was observed in the fat transplants of the rats in the 4 groups. Wet weight of the fat transplants in groups A and B was respectively (0.25 ± 0.04) and (0.26 ± 0.03) g, which were less than those of groups C and D [(0.36 ± 0.03) and (0.35 ± 0.04) g, with P values below 0.05]. HE staining showed that there were less fat cells and more fibroblasts in the transplants of group A, visible fibrous tissue around uneven shape of fat cells in the transplants of group B, and almost identical size and shape of fat cells and unobvious fibrous tissues were found in the transplants of groups C and D. The cells with positive expression of CD31 were distributed in fibrous tissues in larger number but less around fat cells in the transplants of group A, while more of these cells were observed surrounding fat cells in the transplants of group B. There were more cells with positive expression of CD31 distributed surrounding fat cells in the transplants of groups C and D than that in group B. The cells with positive expression of CD31 observed under 400 times field were more in number in groups C (20.5 ± 1.1) and D (22.1 ± 1.0) than in groups A (8.0 ± 3.6) and B (10.9 ± 1.7), with P values below 0.05.

CONCLUSIONSAllogeneic ADSCs combined with autologous AG can significantly improve the early vascularization of fat transplantation as well as autologous ADSCs combined with autologous AG.

Adipocytes ; cytology ; transplantation ; Adipose Tissue ; blood supply ; cytology ; Animals ; Burns ; complications ; metabolism ; pathology ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Neovascularization, Physiologic ; physiology ; Osteogenesis ; Rats ; Stem Cell Transplantation ; Stem Cells ; cytology ; physiology ; Transplantation, Autologous ; Wound Healing ; physiology

OBJECTIVETo observe the level of intracellular reactive oxygen species (ROS) in rats with severe burn and pulmonary microvascular endothelial cells (PMVECs) treated with serum of rat with burn injury, and to investigate the relationship between ROS and apoptosis of PMVECs.

METHODS(1) Twenty-four SD rats were divided into sham injury group ( n = 3) and burn group (n = 21) according to the random number table (the same grouping method below). Rats in burn group were inflicted with 30% TBSA full-thickness scald on the back, and rats in sham injury group were sham injured. Blood samples were collected from abdominal aorta at post injury hour 6, 12, 24, 36, 48, 60, 72 respectively from 3 rats of burn group. The serum content of ROS was assayed by ELISA. The same determination was performed in rats of sham injury group. (2) Five rats were subjected to scald injury as above, and burn serum was prepared 24 hours after injury. Another 5 rats without receiving any treatment were used to prepare normal serum. (3) Marginal pulmonary tissue was harvested from 20 SD young rats. Cells were cultured with tissue block method and indentified with immunohistochemical staining. The third passage of PMVECs in logarithmic phase were inoculated in 6-well plates and 12-well plates. PMVECs in both plates were divided into 4 groups: normal serum group, burn serum group, normal serum + MnTBAP group, and burn serum + MnTBAP group, with 3 wells in each group. Cells in the former 2 groups were respectively cultured with special nutrient solution of endothelial cells without serum added with 15% healthy rat serum or 15% burn rat serum. Cells in the latter 2 groups were cultured with the same culture conditions as in the former two groups correspondingly with addition of 100 µmol/L MnTBAP in the nutrient solution. After being cultured for 24 h, the content of ROS in PMVECs in 6-well plates was detected with flow cytometry. The apoptosis of PMVECs in 12-well plates was observed with acridine orange-ethidium bromide staining, and the apoptosis rate was calculated. Data were processed with one-way analysis of variance and LSD-t test.

RESULTS(1) The serum contents of ROS in rats of burn group were respectively (187 ± 21), (235 ± 22), (231 ± 25), (291 ± 20), (315 ±23) nmol/mL at post injury hour 24, 36, 48, 60, 72, which were significantly higher than that in sham injury group [(141 ± 19) nmol/mL, with t values respectively 7. 86, 9. 57, 13. 87, 14.98, 18.40, P values below 0.01]. (2) Primary cells grew slowly and showed a cobblestone appearance. After passages, cells grew with orderly distribution. The positive rate of coagulation factor VIII of cells was (96 ± 5)% , and thus they were identified as PMVECs. (3) In normal serum group, burn serum group, normal serum + MnTBAP group, and burn serum + MnTBAP group, the contents of ROS in PMVECs were respectively 798 ± 40, 1 294 ± 84, 763 ± 59, 926 ± 42 ( F =93.01, P <0.01), and the apoptosis rates of PMVECs were respectively (6.2 ± 1.3)%, (57.3 ± 6. 7)%, (3.7 ± 0. 8)%, (28.7 ± 5. 7)% (F = 224.50, P <0.01) after being cultured for 24 h. Compared with those of normal serum group, the content of ROS and apoptosis rate of PMVECs in burn serum group increased significantly (with t values respectively 10.40 and 49.06, P values below 0.01). The content of ROS and apoptosis rate of PMVECs in burn serum + MnTBAP group were significantly lower than those in burn serum group (with t values respectively 7.48 and 23.94, P values below 0.01).

CONCLUSIONSSerum content of ROS was increased in severely burned rats. Burn rat serum stimulation on PMVECs can lead to the increase of the intracellular ROS and induce apoptosis. However application of MnTBAP can scavenge ROS and reduce the apoptosis induced by burn rat serum.

Animals ; Apoptosis ; Burns ; blood ; therapy ; Endothelial Cells ; pathology ; Enzyme-Linked Immunosorbent Assay ; Lung ; blood supply ; Oxygen ; Rats ; Reactive Oxygen Species ; blood ; Serum ; metabolism

OBJECTIVETo observe the change in phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) signal pathway in monocytes as induced by serum of rats with electrical burn, and to explore the effects of PI3K/Akt pathway on monocyte-endothelial cell adhesion.

METHODSSixty-four SD rats of clean grade were inflicted with electrical burn for the collection of serum of rats with electrical burn; another group of twenty-four SD rats were used to obtain normal serum without treatment. (1) Human monocyte line THP-1 was routinely cultured. The THP-1 cells in logarithmic phase were divided into normal serum group (resuspended in RPMI 1640 medium with 20% normal rat serum) and burn serum group (resuspended with RPMI 1640 medium with 20% serum of rats with electrical burn) according to the random number table, with 6 wells in each group. Morphology of THP-1 cells in normal serum group was observed at post culture hour (PCH) 24, and that in burn serum group at PCH 3, 6, 24. The contents of TNF-α in culture supernatant were determined by double-antibody sandwich ELISA at the corresponding time point in each group. The state of Akt activation was determined by Western blotting at PCH 3, 6, 24. (2) Another portion of THP-1 cells were divided into 4 groups according to the random number table, with 6 wells in each group. Cells in normal serum group and burn serum group were given with the same culture condition as above; cells in normal serum+inhibitor group and burn serum+inhibitor group were cultured with the same culture conditions as in the former two groups correspondingly with addition of 100 nmol/L wortmannin in the nutrient solution. At PCH 3 and 6, THP-1 cells were added into the well with a monolayer of endothelial cell line EA.hy926 to observe the monocyte-endothelial cell adhesion. Data were processed with one-way analysis of variance and LSD- t test.

RESULTS(1) In normal serum group, THP-1 cells showed growth in suspension, with uniform shape at PCH 24. In burn serum group, the cell shape became irregular though the membrane was complete at PCH 3; cellular size became irregular and cell membrane and cytoplasm were swollen at PCH 6; cell membrane was disrupted with death of cells at PCH 24. The contents of TNF-α in culture supernatant in normal serum group at PCH 24 and in burn serum group at PCH 3, 6, 24 were respectively (38.5 ± 1.4), (75.1 ± 1.5), (91.5 ± 1.8), (117.0 ± 1.4) pg/mL (F = 1 415.306, P < 0.01). The contents of TNF-α in culture supernatant in burn serum group at PCH 3, 6, 24 were all significantly higher than the content of TNF-α in normal serum group at PCH 24 (with t values respectively 29.614, 42.852, 63.485, P values below 0.01). The ratio values of phosphorylated Akt to Akt in burn serum group at PCH 3, 6, 24 were respectively 2.66, 3.69, 1.17 times of those in normal serum group at the corresponding time point. (2) In normal serum group, normal serum+inhibitor group, burn serum group, and burn serum+inhibitor group at PCH 3 and 6, the numbers of THP-1 cells adherent to endothelial cells were respectively (231 ± 45), (280 ± 47), (703 ± 169), (335 ± 85) per 100-time field; (219 ± 49), (235 ± 21), (562 ± 123), (226 ± 29) per 100-time field (with F values respectively 25.630 and 18.975, P values below 0.01). The number of THP-1 cells adhered to EA.hy926 cells was significantly more in burn serum group than in normal serum group at PCH 3 and 6 (with t values respectively 6.189 and 6.601, P values below 0.01). The number of THP-1 cells adherent to EA.hy926 cells was significantly fewer in burn serum+inhibitor group than in burn serum group at PCH 3 and 6 (with t values respectively 6.821 and 6.465, P values below 0.01).

CONCLUSIONSThe serum of rats suffering from electrical burn can induce the monocytes to secrete TNF-α, thus enhancing monocyte-endothelial cell adhesion, but it can be inhibited by blocking PI3K/Akt signal pathway.

Animals ; Burns, Electric ; blood ; Cell Line ; Humans ; Monocytes ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats ; Serum ; Signal Transduction ; Tissue Adhesions ; metabolism ; pathology ; Tumor Necrosis Factor-alpha ; metabolism