Effectiveness of hyperbaric oxygen and ozone applications in tissue healing in generated soft tissue trauma model in rats: an experimental study.

BACKGROUND: Soft tissue trauma is a type of acute traumatic ischemia. We investigated in this study whether the edema, inflammation and ischemia caused by the trauma could be affected positively by hyperbaric oxygen (HBO) and ozone therapy. METHODS: Soft tissue trauma was generated in a total of 63 adult male Sprague-Dawley rats. Subsequently, rats were divided into three groups. The first group was treated with ozone, the second group with HBO, and the third group served as controls. Tissue and blood samples were taken at the end of the procedures. Tissue lipid peroxidation (LPO), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), inducible nitric oxide synthase (iNOS), heme oxygenase (HO)-1, and hypoxia-inducible factor (HIF)-1 levels were detected. Hematoxylin-eosin staining was used to determine the inflammation and edema histopathologically. RESULTS: We also detected HIF-1 activity, which decreases when the oxygen concentration increases, HO-1 activity, which has anti-inflammatory effects, and iNOS activity, which releases in any type of acute case. We determined a statistically significant reduction in iNOS and LPO levels in both the HBO and Ozone groups. A significant decrease in inflammation was detected in both the Ozone and HBO groups compared with the Control group, and a significant decrease in edema was detected in all three groups. CONCLUSION: We think that HBO and Ozone therapy have beneficial effects on biochemical and histopathological findings. Related clinical trials will be helpful in clarifying the effects.

Comparison of hyperbaric oxygen and medical ozone therapies in a rat model of experimental distal colitis.

OBJECTIVES: Previous studies have shown that hyperbaric oxygen (HBO) is effective in reducing the severity of acute distal colitis (ADC). Ozone therapy (OT) reduces inflammation in several pathological conditions. We aimed to compare the effects of HBO therapy and OT in an experimental ADC rat model. MATERIALS AND METHODS: Forty rats were randomly divided into four groups: Sham, ADC, ADC + HBO, and ADC + OT. Rats in the sham group were given isotonic saline. In the remaining groups, ADC was created by intracolonic administration of 4% acetic acid. No treatment was given to the ADC group. The rats in the ADC + HBO and ADC + OT groups were given HBO and ozone treatments, respectively. The administration of acetic acid caused an inflammatory response in all animals. Distal colons and blood samples were obtained. RESULTS: The histopathological score was significantly higher in the ADC group compared to the other groups. The histopathological scores in the ADC + HBO and ADC + OT groups were significantly lower compared to the ADC group (both p < 0.001). The most pronounced therapeutic effect was observed in the ADC + OT group. Malondialdehyde and neopterin levels and superoxide dismutase and glutathione peroxidase activities in the ADC group were significantly higher compared to the other groups (p < 0.001). CONCLUSION: Our data showed that the therapeutic effect of OT is more pronounced than that of HBO therapy. Its possible effect is by means of decreasing inflammation, edema, and oxidative stress. These findings also suggest that it is possible to improve the outcome of ADC by using ozone therapy as an adjuvant therapy.

Efficacy of hyperbaric oxygen therapy and medical ozone therapy in experimental acute necrotizing pancreatitis.

OBJECTIVES: Our aims were to evaluate the efficacy of ozone therapy (OT) in an experimental rat model of acute necrotizing pancreatitis (ANP) and to compare its effects with hyperbaric oxygen (HBO) therapy in this entity. METHODS: Forty Sprague-Dawley rats were divided into sham-operated, ANP, ANP + HBO, and ANP + OT groups. Acute necrotizing pancreatitis was induced by infusing 1-mL/kg 3% sodium taurocholate into the common biliopancreatic duct. Hyperbaric oxygen was administered twice daily at a 2.8-atm pressure for 90 minutes. Ozone therapy was set as daily intraperitoneal injections of 0.7-mg/kg ozone/oxygen gas mixture. Hyperbaric oxygen and OT were continued for 3 days after the induction of ANP. The surviving animals were killed at the fourth day, and their pancreases were harvested for biochemical, microbiological, and histopathologic analyses. RESULTS: Serum amylase/lipase and neopterin levels and tissue oxidative stress parameters were similar to sham's values in both the ANP + HBO and the ANP + OT groups. Histopathologic injury scores were significantly lower in the treatments groups than in the ANP group. When compared with the ANP group, the number of infected rats was significantly lesser in the ANP + HBO and the ANP + OT groups. CONCLUSIONS: Hyperbaric oxygen and OT reduce the severity and the mortality in the experimental rat model of ANP, and a greater benefit was received for OT comparing with HBO.

Does the type of resuscitative fluid affect healing of colonic anastomosis in experimentally induced hemorrhagic shock in rats?

OBJECTIVE: The aim of the study was to investigate the effects of different resuscitative fluids on the healing of intestinal anastomosis in a hemorrhagic-shock rat model. MATERIALS AND METHODS: Closed-colony Wistar male rats (n = 40; 8 rats per group) were subjected to volume-controlled hemorrhagic shock, followed by a 30-min shock phase. The animals were then resuscitated with one of the following fluids (which also corresponds to their respective groups): lactated Ringer's solution (LR), hydroxyethyl starch (HES), 7.5% hypertonic saline (HS) and autologous blood (AB). There was also a control group (CL), which did not experience hemorrhagic shock or receive any resuscitative fluids. All rats underwent laparotomy, segmental resection and anastomosis of the left colon. Five days later, a 2nd laparotomy was performed and the anastomotic bursting pressure was measured in vivo. Thereafter, the anastomosed segment was resected to measure the tissue hydroxyproline level and the grade of anastomotic fibrosis. RESULTS: All experimental groups (LR, HES, HS and AB) exhibited lower anastomotic bursting pressures than the CL group; however, no intergroup differences achieved statistical significance. The mean tissue hydroxyproline level and fibrosis grade also were similar across all 5 groups. CONCLUSION: In traumatic hemorrhagic shock, anastomosis safety does not appear to be affected by the type of fluid used for resuscitation. Moreover, LR, HES and HS all seemed to reinforce healing as effectively as transfused blood.

Effects of hyperbaric oxygen therapy on rabbit skeletal muscle during extremity lengthening.

INTRODUCTION: Extremity lengthening through distraction osteogenesis is limited by the surrounding skeletal muscle and neurovascular structures rather than the bone itself. The purpose of this study is to evaluate the effects of hyperbaric oxygen therapy on skeletal muscle during distraction osteogenesis. MATERIALS AND METHODS: Twenty New Zealand white rabbits were randomly divided into two groups. Right tibia of all rabbits was distracted at a rate of 0.125 mm per 6 h (0.5 mm/day) for 10 days with circular external fixator. Experimental group rabbits (N=10) underwent 2.5 ATA hyperbaric oxygen therapy for 2 h everyday for 20 days, control group rabbits (N=10) did not receive any corresponding treatment. Skeletal muscle perfusion was evaluated with scintigraphy before and after the distraction period. Serum CPK, LDH and AST levels were measured before and after the distraction period. All animals were killed on the 27th day. The right tibias of all animals were removed and tibialis posterior muscle was harvested for histopathologic and histomorphometric assessment with light and electron microscopy. RESULTS: Skeletal muscle perfusion was decreased in the control group in comparison with pre-distraction level (P=0.008). However, no significant decrease was observed in the experimental group (P=0.678). There were no statistical differences in serum CPK, LDH and AST levels between groups (P=0.340, P=0.077, P=0.796). The mean area of the muscle fibers was measured as 398.66+/-9.16 micro2 in the experimental group and 349.44+/-5.76 micro2 in the control group (P=0.000) with light microscopy. Mild fibrosis was observed in connective tissue component of muscle tissue in control group. An average of 26 myofibrils (20-32) was counted in a 16-cm2 unit area in experimental group and 50 myofibrils (35-65) in the control group with electron microscopy. Enlargement in the sarcoplasmic reticulum, degenerative changes in nuclear cytoplasm and increase in myofibril diameter were observed in the control group, which was not observed in the experimental group CONCLUSION: Results of this study suggest that HBO treatment alleviates the detrimental effects of distraction on skeletal muscles and preserves its ultrastructure.

Establishing the use of melatonin as an adjuvant therapeutic against paraquat-induced lung toxicity in rats.

It is well known that the intake of paraquat (PQ) causes severe tissue injury leading to numerous fatalities. Considering that the main target for PQ toxicity is the lung and involves the production of reactive oxygen and nitrogen species, transcription factors and inflammatory cytokines, it may be hypothesized that the combination of a potent antiinflammatory and antioxidant agent may counteract more of PQ's effects than an antiinflammatory agent alone. For this purpose, combination of dexamethasone (Dex) and melatonin (Mel) was compared with Dex alone. A total of 40 male Wistar albino rats were divided into four groups as control, PQ, Dex only, and Dex plus Mel. The animals were given intraperitoneally a toxic dose of 19 mg/kg PQ dissolved in 1 ml saline. Control animals were injected with the same amount of saline only. A dose of 1 mg/kg Dex was administered 2 hrs after PQ administration. In the combination treatment group, 20 mg/kg Mel was given with Dex. All drugs were given every 12 hrs for a total of six doses. Five animals in PQ group and three animals in Dex only group died by the end of the study. No deaths occurred in the Dex+Mel group. Dex exerted improvements in several oxidative and antioxidative parameters. However, combination treatment provided beneficial effects against PQ toxicity far greater than Dex alone. This difference was also apparent when tissues were histologically compared. In conclusion, Mel exhibited strong additive beneficial effects with Dex and can be considered as a safe treatment modality against PQ toxicity.

Effects of hyperbaric oxygen on energy production and xanthine oxidase levels in striated muscle tissue of healthy rats.

We investigated the effects of hyperbaric oxygen (HBO) treatment on striated muscle tissue in healthy rats. The treatment group of rats (n=16) was given HBO daily on weekdays for 2 h over a 4-week period while a control group (n=8) was not treated. Tissue samples were taken from the left and right vastus lateralis before and after the HBO treatment period, respectively, for all rats in both groups. Levels of adenosine monophosphate (AMP), adenosine diphosphate, andenosine triphosphate (ATP) and xanthine oxidase in the muscle tissue were determined. HBO treatment caused a statistically significant increase in ATP (p=0.001) and decrease in AMP (p=0.02) in the HBO-treated group, while there were no significant differences in metabolites in the control group. These results suggest that HBO treatment induces an increase in the ATP levels of muscle tissue with normal mitochondria. Thus, HBO might have some beneficial effects in the treatment of heteroplasmic mitochondrial disease, where normal and defective mitochondria coexist.

Hyperbaric oxygen enhances the efficiency of 5-aminosalicylic acid in acetic acid-induced colitis in rats.

The aim of this study was to assess the efficiency of hyperbaric oxygen alone and in combination with 5-aminosalicylic acid in the acetic acid-induced colitis model, a well-known experimental model of inflammatory bowel disease in rats. Rats were randomly divided into five groups. In the noncolitis control group, rats were given isotonic saline, while in the other groups rats were treated by intracolonic administration of 4% acetic acid. In group 2, the untreated control group, no additional therapy was applied. In groups 3, 4, and 5 hyperbaric oxygen, 5-aminosalicylic acid. and 5-aminosalicylic acid + hyperbaric oxygen therapies were applied, respectively. Administration of acetic acid caused an inflammatory response in all animals. Histopathologic score was significantly higher in group 2 than in any other group. 5-Aminosalicylic acid and hyperbaric oxygen significantly decreased the histopathologic score (P < 0.05). Myeloperoxidase activity was also reduced significantly by 5-aminosalicylic acid (P < 0.05) but not by hyperbaric oxygen. The most prominent ameliorative effect, however, was seen in group 5 and the histopathologic score and myeloperoxidase activity were significantly lower than in groups 3 (P < 0.05) and 4 (P < 0.001). Hydroxyproline level also increased significantly in group 5, but not in groups 3 and 4 (P < 0.001). These findings indicate that hyperbaric oxygen therapy is effective in reducing the extent of colitis induced by acetic acid, although it is not as potent as 5-aminosalicylic acid. The combination of hyperbaric oxygen and 5-aminosalicylic acid, however, led to a much more prominent reduction in the severity of colitis. Hyperbaric oxygen may have a promising place in the treatment of inflammatory bowel disease.