Repetitive pneumoperitoneum with ozonized oxygen as a preventive in lethal polymicrobial sepsis in rats

Ozone as Redox Bioregulator in Preventive Medicine: The Molecular and Pharmacological Basis of the Low-Dose Ozone Concept-A Review

The best form of prevention against human infection through bacteria, viruses, and other parasites is ozone disinfection of wastewater and drinking water as a highly effective, well-known method. Various preclinical studies showed promising results, which are being revisited and reconsidered in times of pandemics and led to interesting results in recent clinical trials and reports, as presented by the example of protective measures against COVID-19 in particularly vulnerable clinical personnel. The application of ozone in the form of the low-dose concept induces its regulation by interference of ozone or its peroxides into the redox equilibrium of the biological system, which finally results in the restoration of the glutathione equilibrium. The antioxidant system is activated, the immune system is modulated, and thus the defense mechanisms are improved. In patients with rheumatoid arthritis, repeated ozone treatments have led to new findings in "immunomodulation" through ozone. The more effective immune response is discussed as the response of innate immune memory and opens interesting aspects for complementary treatment of autoimmune diseases.

Potential therapeutic effect of oxygen-ozone in controlling of COVID-19 disease

Atmospheric ozone is produced when nitrogen oxides react with volatile organic compounds. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome contains a unique N-terminal fragment in the Spike protein, which allows it to bind to air pollutants in the environment. 'Our approach in this review is to study ozone and its effect on the SARS-CoV-2 virus and patients with coronavirus disease 2019 (COVID-19). Article data were collected from PubMed, Scopus, and Google Scholar databases. Ozone therapy has antiviral properties, improves blood flow, facilitates the transfer of oxygen in hypoxemic tissues, and reduces blood coagulation phenomena in COVID-19 patients. Ozone has immunomodulatory effects by modulating cytokines (reduction of interleukin-1, interleukin-6, tumor necrosis factor-α, and interleukin-10), induction of interferon-γ, anti-inflammatory properties by modulating NOD-, LRR- and pyrin domain-containing protein 3, inhibition of cytokine storm (blocking nuclear factor-κB and stimulating nuclear factor erythroid 2-related factor 2 pathway), stimulates cellular/humoral immunity/phagocytic function and blocks angiotensin-converting enzyme 2. In direct oxygen-ozone injection, oxygen reacts with several biological molecules such as thiol groups in albumin to form ozonoids. Intravenous injection of ozonated saline significantly increases the length of time a person can remain hypoxic. The rectal ozone protocol is rectal ozone insufflation, resulting in clinical improvement in oxygen saturation and biochemical improvement (fibrinogen, D-dimer, urea, ferritin, LDH, interleukin-6, and C-reactive protein). In general, many studies have shown the positive effect of ozone therapy as a complementary therapy in the recovery of COVID-19 patients. All the findings indicate that systemic ozone therapy is nontoxic and has no side effects in these patients.

Pulmonary effects of ozone therapy at different doses combined with antibioticotherapy in experimental sepsis model

Purpose

This experimental sepsis model created with Escherichia coli aimed to investigate the histopathological effects of two different doses of ozone combined with antibiotherapy on lung tissue.

Methods

Rats were divided into 5 groups. Then sepsis was induced intraperitoneally in the first 4 groups. The 1^st group was treated with cefepime, the 2^nd and 3^rd groups were treated with cefepime combined with ozone at a dose of 0.6 mg/kg and 1.1 mg/kg. Lung tissue sections were stained with hematoxylin-eosin and assessed under light microscope and scored between 0-4 in terms of histopathological findings.

Results

In the comparisons between Group 1 and Group 4 in terms of cellular damage (p=0.030), inflammation (p=0.000) and overall score (p=0.007), statistically significant positive effects were observed in favor of Group 1. In the comparisons of Groups 2 and 3 with Group 4, only positive effects were observed in terms of inflammation (p=0.020, p=0.012, respectively).

Conclusion

Although negative histopathological effects of ozone on tissue injury were detected, it was noteworthy that the increase in the ozone dose reduced the number of damaged parameters.

Evidence for the absence of visceral pain in C57BL6/N mice subjected to therapeutically relevant O3/O2-pneumoperitoneum

Each different gas that is used to induce a pneumoperitoneum (PP) exhibits individual effects within the peritoneal cavity. This might include adverse effects such as pain and/or inflammatory reactions. The acute effects of ozonized oxygen (O₃/O₂), a highly oxidative gas mixture, after being insufflated into the peritoneal cavity are analysed in this study. Using the abdominal constriction response ('writhing') assay of chemical nociception in C57BL6/N mice, O₃/O₂-PP was found not to be associated with visible pain responses and did not alter the c-fos expression in the spinal cord. In addition, mRNA expression levels of the pro-inflammatory cytokines, interleukin (IL)-1β and IL-6, were found unaltered in the spleen 2 h after insufflation. In conclusion, O₃/O₂-PP is free of adverse pain and does not trigger inflammatory immune responses.

Antimicrobial strategies centered around reactive oxygen species--bactericidal antibiotics, photodynamic therapy, and beyond

Reactive oxygen species (ROS) can attack a diverse range of targets to exert antimicrobial activity, which accounts for their versatility in mediating host defense against a broad range of pathogens. Most ROS are formed by the partial reduction in molecular oxygen. Four major ROS are recognized comprising superoxide (O2•-), hydrogen peroxide (H2O2), hydroxyl radical (•OH), and singlet oxygen ((1)O2), but they display very different kinetics and levels of activity. The effects of O2•- and H2O2 are less acute than those of •OH and (1)O2, because the former are much less reactive and can be detoxified by endogenous antioxidants (both enzymatic and nonenzymatic) that are induced by oxidative stress. In contrast, no enzyme can detoxify •OH or (1)O2, making them extremely toxic and acutely lethal. The present review will highlight the various methods of ROS formation and their mechanism of action. Antioxidant defenses against ROS in microbial cells and the use of ROS by antimicrobial host defense systems are covered. Antimicrobial approaches primarily utilizing ROS comprise both bactericidal antibiotics and nonpharmacological methods such as photodynamic therapy, titanium dioxide photocatalysis, cold plasma, and medicinal honey. A brief final section covers reactive nitrogen species and related therapeutics, such as acidified nitrite and nitric oxide-releasing nanoparticles.

Ozone therapy as an adjunct to vancomycin enhances bacterial elimination in methicillin resistant Staphylococcus aureus mediastinitis

BACKGROUND

We aimed to investigate the influence of intraperitoneal ozone therapy on bacterial elimination and mediastinal inflammation in experimental Staphylococcus aureus mediastinitis.

MATERIALS AND METHODS

Forty Wistar-Albino rats were randomized into five groups (eight per group) as follows: uncontaminated group, untreated contaminated group, ozone group, vancomycin group, and vancomycin + ozone group. Uncontaminated group underwent upper median sternotomy. The remaining four groups were inoculated with 0.5 mL 10(8) colony-forming units/mL methicillin-resistant Staphylococcus aureus in the mediastinal and sternal layers. Untreated contaminated group had no treatment. Rats in the vancomycin group received intramuscular vancomycin (40 mg/kg/d), and ozone was administered intraperitoneally (70 μg/mL, 1 mg/kg/d) in the ozone group for the treatment of mediastinitis. Vancomycin + ozone group rats were treated by the combination of both methods. At the end of 10 d, quantitative bacterial cultures and sternal tissue samples were obtained for determination of bacterial counts and histologic degree of inflammation.

RESULTS

Both the vancomycin and the ozone treatments caused significant reduction of bacterial counts in quantitative bacterial cultures. Combination of vancomycin and ozone treatments resulted in further reduction of bacterial counts in mediastinum and sternum. Histologic examination of tissue samples revealed significant reduction in severity of mediastinitis related inflammation in vancomycin and vancomycin + ozone groups compared with untreated contaminated group.

CONCLUSIONS

Ozone therapy as an adjunct to vancomycin leads to enhanced bacterial elimination in infected sternal and mediastinal tissues in experimental methicillin-resistant Staphylococcus aureus mediastinitis. The benefit of adjuvant ozone therapy is suggested to be related to its bactericidal effect.

Ozone preconditioning and exposure to ketamine attenuates hepatic inflammation in septic rats

INTRODUCTION

The objective of this study was to evaluate the interaction between ozone oxidative preconditioning and the anesthetic ketamine on cytoplasmic nuclear factor κB (NF-κB) levels in a rat endotoxic shock model.

MATERIAL AND METHODS

Forty Wistar rats were randomly divided into 5 groups: I - control group; II - rats intraperitoneally (i.p.) treated with LPS; III - rats treated with LPS and then treated with ketamine; IV - animals pre-treated with O(3)/O(2) mixture for 5 days, then treated with LPS for 24 h followed by infusion with ketamine; V - O(3)/O(2) pre-treatment, as described above for IV, followed by LPS infusion, and then 0.9% saline. In addition to histological examination of the liver, the levels of NF-κB were determined by SABC immunohistochemistry in each group.

RESULTS

Histological damage was observed in the lipopolysaccharide (LPS) group. It was characterized by hepatic disarray, hepatic lobule distortion, congestion of liver sinusoids, hepatocyte swelling and necrosis, and granulocyte infiltration. These changes were not obvious in the O(3)/O(2) + LPS + ketamine group. The normal control group had low activity of NF-κB, but that activity was markedly increased in the LPS group (p < 0.05). The NF-κB level was significantly decreased in the O(3)/O(2) + LPS + ketamine group (p < 0.05) when compared with the ketamine-treated group, and was almost equal to the control group.

CONCLUSIONS

We confirmed that the preconditioning effect of ozone enhances the biological effectiveness of ketamine by altering NF-κB activity, which may play an important role in sepsis-induced liver injury in rats.

Effects of ozone oxidative preconditioning on different hepatic biomarkers of oxidative stress in endotoxic shock in mice

In endotoxic shock, variations are known to occur in different biochemical parameters of oxidative stress. Ozone oxidative preconditioning (OOP) is a good candidate to restore the redox balance on different tissue. This investigation examined the effect of OOP on different biomarkers of oxidative stress in hepatic tissue of mice treated with lipopolysaccharide (LPS). LPS doses of 30 mg/kg were administered intraperitoneally (i.p.) and pretreatment with ozone/oxygen mixture (OOM) was applied i.p. at 0.2, 0.4, and 1.2 mg/kg once daily during 5 days before LPS injection. The mice were euthanized under ether atmosphere at different times, 1 and 24 h after LPS injection. Hepatic tissue from all animals was taken for biochemical determinations of oxidative stress parameters such as thiobarbituric acid reactive substances (TBARS) content and activity of antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione S-transferase (GST). The results demonstrated that OOP reduces levels of TBARS content and increases the activity of GPx in hepatic tissue. In conclusion, OOP was able to recover the redox balance and in this way to protect the animals against the oxidative damage induced by endotoxemia.

Ozone therapy and hyperbaric oxygen treatment in lung injury in septic rats

Various therapeutic protocols were used for the management of sepsis including hyperbaric oxygen (HBO) therapy. It has been shown that ozone therapy (OT) reduced inflammation in several entities and exhibits some similarity with HBO in regard to mechanisms of action. We designed a study to evaluate the efficacy of OT in an experimental rat model of sepsis to compare with HBO. Male Wistar rats were divided into sham, sepsis+cefepime, sepsis+cefepime+HBO, and sepsis+cefepime+OT groups. Sepsis was induced by an intraperitoneal injection of Escherichia coli; HBO was administered twice daily; OT was set as intraperitoneal injections once a day. The treatments were continued for 5 days after the induction of sepsis. At the end of experiment, the lung tissues and blood samples were harvested for biochemical and histological analysis. Myeloperoxidase activities and oxidative stress parameters, and serum proinflammatory cytokine levels, IL-1β and TNF-α, were found to be ameliorated by the adjuvant use of HBO and OT in the lung tissue when compared with the antibiotherapy only group. Histologic evaluation of the lung tissue samples confirmed the biochemical outcome. Our data presented that both HBO and OT reduced inflammation and injury in the septic rats' lungs; a greater benefit was obtained for OT. The current study demonstrated that the administration of OT as well as HBO as adjuvant therapy may support antibiotherapy in protecting the lung against septic injury. HBO and OT reduced tissue oxidative stress, regulated the systemic inflammatory response, and abated cellular infiltration to the lung demonstrated by findings of MPO activity and histopathologic examination. These findings indicated that OT tended to be more effective than HBO, in particular regarding serum IL-1β, lung GSH-Px and histologic outcome.

Evaluation of the effects of ozone therapy in the treatment of intra-abdominal infection in rats

INTRODUCTION

The antibacterial effect of ozone (O(3)) has been described in the extant literature, but the role of O(3) therapy in the treatment of certain types of infection remains controversial.

OBJECTIVES

To evaluate the effect of intraperitoneal (i.p.) O(3) application in a cecal ligation/puncture rat model on interleukins (IL-6, IL-10) and cytokine-induced neutrophil chemoattractant (CINC)-1 serum levels, acute lung injury and survival rates.

METHODS

FOUR ANIMAL GROUPS WERE USED FOR THE STUDY: a) the SHAM group underwent laparotomy; b) the cecal ligation/puncture group underwent cecal ligation/puncture procedures; and c) the CLP+O(2) and CLP+O(3) groups underwent CLP+ corresponding gas mixture infusions (i.p.) throughout the observation period. IL-6, CINC-1 and IL-10 concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Acute lung injury was evaluated with the Evans blue dye lung leakage method and by lung histology. P<0.05 was considered significant.

RESULTS

CINC-1 was at the lowest level in the SHAM group and was lower for the CLP+O(3) group vs. the CLP+O(2) group and the cecal ligation/puncture group. IL-10 was lower for the SHAM group vs. the other three groups, which were similar compared to each other. IL-6 was lower for the SHAM group vs. all other groups, was lower for the CLP+O(3) or CLP+O(2) group vs. the cecal ligation/puncture group, and was similar for the CLP+O(3) group vs. the CLP+O(2) group. The lung histology score was lower for the SHAM group vs. the other groups. The Evans blue dye result was lower for the CLP+O(3) group vs. the CLP+O(2) group and the cecal ligation/puncture group but similar to that of the SHAM group. The survival rate for the CLP+O(3) group was lower than for the SHAM group and similar to that for the other 2 groups (CLP and CLP+O(2)).

CONCLUSION

Ozone therapy modulated the inflammatory response and acute lung injury in the cecal ligation/puncture infection model in rats, although there was no improvement on survival rates.

Analysis of the bactericidal effect of ozone pneumoperitoneum

PURPOSE

To assess the bactericidal action of ozone pneumoperitonium, and to compare the results with CO2.

METHODS

It was used 36 Wistar rats. The animals, under anesthesia, were inoculated with 2ml of E. coli ATCC at a concentration of 10(10)UFC, and 1ml of BaSO4, into the peritoneal cavity. They were divided into three groups: Group 1, CO2 pneumoperitoneum was performed for 15 minutes; Group 2, ozone pneumoperitoneum was performed for 5 minutes at a concentration of 42microg/ml, and Group 3, ozone pneumoperitoneum was performed for 5 minutes at a concentration of 62microg/ml. Six animals from each group were sacrificed after the experiment, and the remaining 6 observed for 24 hours. Material was collected from the cavity of all animals for microbiological study.

RESULTS

Ozone presented a greater bactericidal effect than CO2 in those animals sacrificed immediately after pneumoperitoneum. In the animals studied 24 hours after pneumoperitoneum evidenced no difference in bactericidal effect between the two gases. Moreover, no difference in mortality was observed.

CONCLUSION

Ozone has a more potent bactericidal effect than carbon dioxide gas, although this did not influence survival of the animals.

Preconditioning with ozone/oxygen mixture induces reversion of some indicators of oxidative stress and prevents organic damage in rats with fecal peritonitis

OBJECTIVE AND DESIGN

Reactive oxygen and nitrogen species are involved in the pathogenesis of sepsis syndrome with peritonitis and the septic shock. The aim of this study was to determine whether ozone oxidative preconditioning (OOP) may exert beneficial effects in the prevention and treatment of sepsis syndrome in rats inoculated by the intraperitoneal route (i.p.) with fecal material and also to determine if antioxidant enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) may exert protective effects against this systemic inflammatory disorder.

MATERIALS AND METHODS

Male Wistar rats were used. SOD and GPx activities were determined in erythrocytes. Thiobarbituric acid reactive substances (TBARS) content as biomarkers of oxidative stress, alanine amino transferase (ALT), aspartate amino transferase (AST) and creatinine (CRE) were measured in blood serum and myeloperoxidase (MPO) in lung tissue as markers of organs damage.

RESULTS

In rats submitted to OOP, SOD and GPx activities were significantly increased and it was accompanied by significant decrease of TBARS content in blood serum. OOP also significantly reduced levels of ALT, AST and CRE in blood serum as well as MPO in rat lung.

CONCLUSION

The results support the important role of SOD and GPx in the protective effects of OOP against organ damage induced by fecal peritonitis in rats.

Treatment with ozone/oxygen-pneumoperitoneum results in complete remission of rabbit squamous cell carcinomas

Head and neck squamous cell carcinomas (HNSCC) represent a group of metastasizing tumors with a high mortality rate in man and animals. Since the biomolecule ozone was found to inhibit growth of various carcinoma cells in vitro we here applied the highly aggressive and lethal VX2 carcinoma HNSCC tumor model of the New Zealand White rabbit to test whether ozone exerts antitumorous effects in vivo. Therapeutic insufflation of medical ozone/oxygen (O(3)/O(2)) gas mixture into the peritoneum (O(3)/O(2)-pneumoperitoneum) at an advanced stage of tumor disease led to a survival rate of 7/14 rabbits. Six of the seven surviving rabbits presented full tumor regression and the absence of local or distant lung metastases. Insufflation of pure oxygen (O(2)) resulted in a survival rate of 3/13 animals accompanied by full tumor remission in 2 of the 3 surviving animals. Of the 14 sham-treated animals only 1 had spontaneous tumor remission and survived. No adverse effects or changes in standard blood parameters were observed after repeated intraperitoneal insufflations of the O(3)/O(2) or O(2) gas. Animals with O(3)/O(2)-induced tumor eradication developed tolerance against reimplantation of the VX2 tumor. This could be reversed by immune suppression with a combination of dexamethasone and cyclosporin A suggesting an antitumorous effect of O(3)/O(2)-mediated activation of the body's own immunosurveillance. Although the exact mechanisms of action are still unclear the present data point to O(3)/O(2)-pneumoperitoneum as a promising new strategy in anticancer therapy.

Efficiency of tazobactam/piperacillin in lethal peritonitis is enhanced after preconditioning of rats with O3/O2-pneumoperitoneum

Insufflation of ozonized oxygen into the peritoneum (O3/O2-pneumoperitoneum [O3/O2-PP]) of rats reduced the lethality of peritonitis. We evaluated the prophylactic effect of O3/O2-PP combined with tazobactam/piperacillin (TZP) in polymicrobial lethal peritonitis. Wistar rats were conditioned by daily repeated insufflation of ozone for 5 days, and hematologic parameters were determined. Sepsis was induced by i.p. injection of cecal material derived from donor rats. Simultaneously, TZP was applied at a single dosage of 65 mg/kg or at two dosage schedules of 65 mg/kg each at an interval of 1 h. The conditioning effect of O3/O2-PP on the number of blood cells was measured before inoculation of bacteria. The mRNA levels of proinflammatory cytokine IL-lbeta and TNF-alpha were determined at 4 h post infection in spleen and liver by semiquantitative in situ hybridization analysis. Preconditioning of rats by O3/O2-PP enhanced the number of blood leukocytes and granulocytes and increased the survival rate of septic rats up to 33%. The combination of O3/O2-PP and TZP further enhanced the survival rate up to 93%. This effect was accompanied by a reduced amount of IL-1beta and TNF-alpha mRNA in spleen and liver. In contrast, in non-infected animals the combination of O3/O2-PP and TZP enhanced IL-1beta and TNF-alpha mRNA in the spleen and IL-1beta mRNA in liver when compared with TZP- and sham-treated controls. The preconditioning effect of O3/O2-PP seems to support the biological effectiveness of TZP by altering the immune status before and during the onset of sepsis. The combined therapy could be a simple, preoperative intervention for abdominal surgery to reduce postoperative morbidity and mortality.

Effects of ozone oxidative preconditioning on TNF-alpha release and antioxidant-prooxidant intracellular balance in mice during endotoxic shock

Ozone oxidative preconditioning is a prophylactic approach, which favors the antioxidant-prooxidant balance for preservation of cell redox state by the increase of antioxidant endogenous systems in both in vivo and in vitro experimental models. Our aim is to analyze the effect of ozone oxidative preconditioning on serum TNF-α levels and as a modulator of oxidative stress on hepatic tissue in endotoxic shock model (mice treated with lipopolysaccharide (LPS)). Ozone/oxygen gaseous mixture which was administered intraperitoneally (0.2, 0.4, and 1.2 mg/kg) once daily for five days before LPS (0.1 mg/kg, intraperitoneal). TNF-α was measured by cytotoxicity on L-929 cells. Biochemical parameters such as thiobarbituric acid reactive substances (TBARS), enzymatic activity of catalase, glutathione peroxidase, and glutathione-S transferase were measured in hepatic tissue. One hour after LPS injection there was a significant increase in TNF-α levels in mouse serum. Ozone/oxygen gaseous mixture reduced serum TNF-α levels in a dose-dependent manner. Statistically significant decreases in TNF-α levels after LPS injection were observed in mice pretreated with ozone intraperitoneal applications at 0.2 (78%), 0.4 (98%), and 1.2 (99%). Also a significant increase in TBARS content was observed in the hepatic tissue of LPS-treated mice, whereas enzymatic activity of glutathion-S transferase and glutathione peroxidase was decreased. However in ozone-treated animals a significant decrease in TBARS content was appreciated as well as an increase in the activity of antioxidant enzymes. These results indicate that ozone oxidative preconditioning exerts inhibitory effects on TNF-α production and on the other hand it exerts influence on the antioxidant-prooxidant balance for preservation of cell redox state by the increase of endogenous antioxidant systems.