Effects of medical ozone therapy on acetaminophen-induced nephrotoxicity in rats

The Protective Role of Ozone Therapy in Kidney Disease: A Review

Ozone (O3) is a reactive oxygen species (ROS) that can interact with cellular components and cause oxidative stress. Following said logic, if O3 induces such a stressful milieu, how does it exert antioxidant functions? This is mediated by controlled toxicity produced by low concentrations of O3, which enhance the cell’s suppliance of antioxidant properties without causing any further damage. Therapeutic concentrations vary extensively, although 50 µg/mL is commonly used in experimental and clinical procedures, given that augmented concentrations might work as germicides or cause endogenous damage. O3 therapy has been shown to be effective when applied before or after traumatic renal procedures, whether caused by ischemia, xenobiotics, chronic damage, or other models. In this review, we focus on discussing the role of O3 therapy in different models of kidney damage associated with fibrosis, apoptosis, oxidative stress, and inflammation. We integrate and report knowledge about O3 in renal therapy, debunking skepticism towards unconventional medicine, explaining its proven therapeutic properties, and thus providing background for its use in further research as well as in clinical settings.

Notoginsenoside Fc ameliorates renal tubular injury and mitochondrial damage in acetaminophen-induced acute kidney injury partly by regulating SIRT3/SOD2 pathway

Introduction

Mitochondria dysfunction is one of the primary causes of tubular injury in acute kidney injury (AKI). Notoginsenoside Fc (Fc), a new saponin isolated from Panax notoginseng, exhibited numerous pharmacological actions. However, the beneficial effects of Fc on renal tubular impairment and mitochondrial dysfunction in AKI have not been fully studied.

Methods

In this study, we established acetaminophen (APAP)-induced AKI model in mice to examine the therapeutic impacts of Fc on AKI.

Results

Our results showed that Fc could decrease the levels of the serum creatinine (Scr), blood urea nitrogen (BUN) and Cystatin C in mice with AKI. Fc also ameliorated renal histopathology, renal tubular cells apoptosis and restored expression of apoptosis-related proteins such as Bax, Bcl-2 and caspase3 (C-caspase3). Additionally, Fc increased the protein expression of SIRT3 and SOD2 in kidneys from mice with AKI. In vitro studies further showed Fc reduced the apoptosis of HK-2 cells exposure to APAP, attenuated the loss of mitochondrial membrane potential and decreased the formation of mitochondrial superoxide. Fc also partly restored the protein expression of Bax, Bcl-2, C-Caspase3, SIRT3, and SOD2 in HK-2 cells exposure to APAP.

Conclusion

In summary, Fc might reduce renal tubular injury and mitochondrial dysfunction in AKI partly through the regulation of SIRT3/SOD2 pathway.

Nobiletin attenuates acetaminophen-induced hepatorenal toxicity in rats

The study aimed to examine the effects of nobiletin on the toxicity model induced with acetaminophen (APAP). For this purpose, 24 adult male rats were equally divided into four groups. The groups were the control group (group 1); dimethyl sulfoxide only, the APAP group (group 2) received a single dose of APAP 1000 mg/kg on the 10th day of experiment; the Nobiletin group (group 3), nobiletin (10 mg/kg) for 10 days; and the APAP + Nobiletin group (group 4), nobiletin (10 mg/kg) for 10 days with a single dose of APAP (1000 mg/kg) administered on the 10th day and the experiment ended after 48 hours. At the end of the study, a significant increase in malondialdehyde, interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) levels and a significant decrease in glutathione levels, glutathione peroxidase activities and nuclear factor erythroid-derived 2-like 2 (Nrf-2) and heme oxygenase-1 (HO-1) expressions were observed with APAP application in liver and kidney tissues. Serum aspartate transaminase (AST), alanine transaminase (ALT), urea, and creatinine levels were also significantly increased in the APAP group. However, nobiletin treatment in group 4 reversed oxidative stress and inflammatory and histopathological signs caused by APAP. It is concluded that nobiletin may be a beneficial substance that confers hepatorenal protection to APAP-induced toxicity via antioxidant and anti-inflammatory mechanisms.

The Effect of Ozone on Colonic Epithelial Cells

Due to its strong oxidation activity, ozone has been well known to kill bacteria and exert toxic effects on human tissues. At the same time, ozone is being used for the treatment of diseases such as inflammatory bowel disease in some European countries. However, the use of ozone for therapeutic purposes, despite its strong toxic effects, remains largely unexplored. Interestingly, we found that intrarectal administration of ozone gas induced transient colonic epithelial cell damage characterized by the impairment of cell survival pathways involved in DNA replication, cell cycle, and mismatch repair. However, the damaged cells were rapidly extruded from the epithelial layer, and appeared to immediately stimulate turnover of the epithelial layer in the colon. Therefore, it is possible that ozone gas is able to trigger damage-induced rapid regeneration of intestinal epithelial cells, and that this explains why ozone does not cause harmful or persistent damage in the colon.

HSP72 is an early biomarker to detect cisplatin and acetaminophen nephrotoxicity

OBJECTIVE

To evaluate whether the urinary HSP72 levels (uHSP72) are a useful biomarker for early diagnosis of acute kidney injury (AKI) induced by two widely used drugs: cisplatin and acetaminophen.

MATERIALS AND METHODS

To analyze the time-course of nephrotoxic injury and uHSP72 levels, male Wistar rats were administered a single high dose of cisplatin (7 mg/kg) or acetaminophen (750 mg/kg) and were assessed at 6, 12, 24, 48, 72, 96 and 120 h.

RESULTS

AKI induced by cisplatin was characterized by tubular injury that started at 6 h and was enhanced after 48 h. Plasma creatinine was increased only after 72 h. In contrast, uHSP72 levels were augmented after 6 h and were enhanced after 48 h of cisplatin administration, which was consistent with the tubular injury. In acetaminophen-induced AKI, the tubular lesions were less severe and predominantly characterized by tubular cell detachment. Interestingly, uHSP72 levels were increased after 6 h of acetaminophen injection and remained elevated at the following time points, reflecting the tubular injury, even in the absence of major functional changes.

CONCLUSIONS

In two models of renal injury induced by nephrotoxic drugs, we showed that uHSP72 could be used as an early biomarker to detect subtle to severe tubular injury.

Ozone therapy ameliorates paraquat-induced lung injury in rats

Paraquat (PQ) overdose can cause acute lung injury and death. Ozone therapy (OT) was previously demonstrated to alleviate inflammation and necrosis in various pathologies. We therefore hypothesized that OT has ameliorative and preventive effects on PQ-induced lung damage due to anti-inflammatory and antioxidants properties. Sprague-Dawley rats (n = 24) were separated into three groups: sham, PQ, and PQ+OT groups. 15 mg/kg PQ was administered intraperitoneally in PQ and PQ+OT groups to induce experimental lung injury. One hour after PQ treatment, PQ+OT group was administered a single dose of ozone-oxygen mixture (1 mg/kg/day) by intraperitoneal route for four consecutive days. The animals were sacrificed on fifth day after PQ administration. Blood samples and lung tissues were collected to evaluate the inflammatory processes, antioxidant defense and pulmonary damage. Serum lactate dehydrogenase (LDH) and neopterin levels, tissue oxidative stress parameters, total TGF-β1 levels, and histological injury scores in PQ+OT group were significantly lower than PQ group (P<0.05, PQ vs. PQ+OT). Total antioxidant capacity in PQ+OT group was significantly higher than PQ group (P < 0.05, PQ+OT vs. PQ). These findings suggest that outcome in PQ-induced lung injury may be improved by using OT as an adjuvant therapy.

The protective effects of ozone therapy in a rat model of acetaminophen-induced liver injury

OBJECTIVES

Acetaminophen (APAP) overdose may cause acute liver injury. Ozone therapy (OT) is shown to reduce inflammation and necrosis in several entities. Thus, we have designed this study to evaluate the efficacy of OT in a rat model of APAP-induced liver injury.

METHODS

Twenty-seven Sprague-Dawley rats were divided into three groups: sham, APAP and APAP+OT groups. In the APAP and the APAP+OT groups, liver injury was induced by oral administration of 1 g/kg APAP. The APAP+OT group received a single dose ozone/oxygen mixture (0.7 mg/kg) intraperitoneally 1h after APAP administration. All animals were killed at 24 hour after APAP administration. Blood samples and liver tissues were harvested to determine liver injury and oxidative stress parameters. Liver tissues and blood samples were obtained for biochemical and histopathological analyses.

RESULTS

APAP administration caused necrosis in the liver after 24h. The degrees of liver necrosis of the APAP group were higher than the other groups (in both p<0.05, respectively). In the APAP+OT group, liver antioxidant enzymes activities were significantly higher than the APAP group (p<0.05), but were lower than the sham group (p<0.05). In the sham group, serum neopterin, a marker of cell-mediated immunity, concentrations (4.8±1.2 nmol/L) were lower than the APAP (14.7±1.4 nmol/L) and APAP+OT groups (7.5±2.4 nmol/L) (in both p<0.05, respectively).

CONCLUSION

Our results showed that OT prevented liver necrosis in rats and reduced neopterin levels. These findings suggest that the use of OT as an adjuvant therapy which might improve the outcome in APAP induced liver injury.

Medical ozone therapy decreases postoperative uterine adhesion formation in rats

PURPOSE

Various studies have been performed to find out novel treatment strategies to prevent postoperative adhesion formation. Ozone therapy (OT) is shown to reduce inflammation in several pathological conditions. Therefore, we aimed to evaluate the efficacy of OT in a rat model of experimental uterine adhesion (EUA).

METHODS

Thirty female Wistar rats (200-250 g) were divided into three groups: sham, EUA and EUA+OT. EUA and EUA+OT groups were subjected to the postoperative adhesion procedure by bipolar coagulation on the uterine horns and corresponding pelvic sidewall parietal peritoneum. EUA+OT group received 0.7 mg/kg daily single dose for 3 days of ozone/oxygen mixture intraperitoneally after adhesion induction. All animals were killed on the 7th day and uterine adhesions were scored. Uterine tissues and peritoneal washing fluid were harvested for all analyses.

RESULTS

Uterine malondialdehyde levels in the EUA group were significantly higher compared to the other groups. However, in the EUA group, uterine superoxide dismutase and glutathione peroxidase activities were lower than in other groups. Peritoneal fluid TNF-α levels were found to be significantly different for all groups (p < 0.001). Macroscopic total adhesion score was significantly higher in the EUA group compared to the other groups (p < 0.001). But, total score in the EUA+OT group was lower than in the EUA group (p = 0.006).

CONCLUSIONS

Medical OT prevents postoperative uterine adhesions by modulating TNF-α levels and oxidative/antioxidative status in an experimental uterine adhesion model.

Ozone acting on human blood yields a hormetic dose-response relationship

The aim of this paper is to analyze why ozone can be medically useful when it dissolves in blood or in other biological fluids. In reviewing a number of clinical studies performed in Peripheral Arterial Diseases (PAD) during the last decades, it has been possible to confirm the long-held view that the inverted U-shaped curve, typical of the hormesis concept, is suitable to represent the therapeutic activity exerted by the so-called ozonated autohemotherapy. The quantitative and qualitative aspects of human blood ozonation have been also critically reviewed in regard to the biological, therapeutic and safety of ozone. It is hoped that this gas, although toxic for the pulmonary system during prolonged inhalation, will be soon recognized as a useful agent in oxidative-stress related diseases, joining other medical gases recently thought to be of therapeutic importance. Finally, the elucidation of the mechanisms of action of ozone as well as the obtained results in PAD may encourage clinical scientists to evaluate ozone therapy in vascular diseases in comparison to the current therapies.