Vascular effects of continuous hyperbaric oxygen exposure: experimental outlook.

Hyperbaric oxygen (HBO) treatment aims to restore tissue oxygenation by inhaling 100% oxygen in pressure rooms. Although beneficial effects have been reported with regard to re-oxygenated ischemic tissues, conflicting findings have been presented concerning the paradoxical tissue response following reperfusion and/or the different responses of non-ischemic normal tissues to increased oxygen exposure. The present study sought to experimentally investigate the impact of continuous HBO treatments on normal aortic tissue. New Zealand rabbits were placed in pressure rooms for 90 minutes per day under 2.5 atmospheric pressure and exposed to HBO for 28 days. Normal structural histology was obtained in the control group. Foam cells were detected in the aortic intimae, thickening and undulation were visualized in the endothelium, and localized separations were observed in the tunica media in the study group compared with the control group. Moreover, salient vasa vasorum was detected in the study group via histopathology. These findings suggest that continuous HBO exposures disrupt the normal vascular structure of a healthy aorta.

Effects of Hyperbaric Oxygen Treatment on Renal System.

INTRODUCTION: Hyperbaric oxygen (HBO) treatment is steadily increasing as a therapeutic modality for various types of diseases. Although good clinical outcomes were reported with HBO treatment for various diseases, the multisystemic effects of this modality are still unclear. This study aimed to investigate the renal effects of HBO experimentally. MATERIALS AND METHODS: Fourteen New Zealand White rabbits were divided into 2 groups randomly as the control group and the study group. The study group received HBO treatment for 28 days (100% oxygen at 2.5 atmospheres for 90 minutes daily) and the control group was used to obtain normal renal tissue of the animal genus. After the intervention period, venous blood samples were obtained, and renal tissue samples were harvested for comparisons. RESULTS: Normal histological morphology was determined with Masson trichrome staining and periodic acid-Schiff staining in the control group. Atrophic glomerular structures, vacuolated tubule cells, and degeneration were detected in the renal samples of the study group with Masson trichrome staining. Additionally, flattening was observed on the brush borders of the proximal tubules, and tubular dilatation was visualized with periodic acid-Schiff staining. The histopathologic disruption of renal morphology was verified with detection of significantly elevated kidney function laboratory biomarkers in the study group. CONCLUSIONS: Our findings suggests that HBO has adverse effects on renal glomerulus and proximal tubules. However, the functional effects of this alteration should be investigated with further studies.

Protective effects of ginseng extracts and common anti-aggregant drugs on ischaemia-reperfusion injury.

OBJECTIVE: Ginseng is a traditional herbal medicinal product widely used for various types of diseases because of its cellular protective effects. Possible protective effects of ginseng were investigated in blood, cardiac and renal tissue samples and compared with common anti-aggregant agents in an animal ischaemia-reperfusion (I/R) model. METHODS: Twenty rats were equally divided into four different groups as follows: control group (I/R-induced group without drug use), group I (acetylsalicylic acid-administered group), group II (clopidogrel bisulfate-administered group), group III (ginsenoside Rb1-administered group). For the groups assigned to a medication, peripheral I/R was induced by clamping the femoral artery one week after initiation of the specified medication. After reperfusion was initiated, cardiac and renal tissues and blood samples were obtained from each rat with subsequent analysis of nitrogen oxide (NOx), malondialdehyde (MDA), paraoxonase 1 (PON1) and prolidase. RESULTS: NOx levels were similar in each group. Significant decrements were observed in serum PON1 levels in each group when compared with the control (p < 0.05). Serum MDA levels were significantly lower in groups II and III (p < 0.05). Ameliorated renal prolidase levels were detected in study groups (p < 0.05) and recovered cardiac prolidase levels were obtained in groups II and III (p < 0.05). CONCLUSION: These findings indicate that ginseng extracts may have a potential beneficial effect in I/R injury. However, more comprehensive studies are required to clarify the hypothetical cardiac, renal and systemic protective effects in reperfusion-induced oxidative damage.

Investigation of possible prophylactic, renoprotective, and cardioprotective effects of thromboprophylactic drugs against ischemia-reperfusion injury.

The aim of this study was to investigate whether anticoagulant and antiaggregant agents have protective effects against oxidative damage induced by peripheral ischemia-reperfusion (I/R). Groups were created as follows: control group, I/R group (sham group), I/R plus acetylsalicylic acid (Group I), I/R+clopidogrel (Group II), I/R+rivaroxaban (Group III), I/R+bemiparin sodium (Group IV), and I/R+enoxaparin sodium (Group V). In Groups I, II, III, IV, and V, drugs were administered daily for 1 week before I/R creation. Peripheral I/R was induced in the I/R groups by clamping the right femoral artery. The rats were sacrificed 1 hour after reperfusion. Nitrogen oxide levels, malondialdehyde (MDA) levels, paraoxonase-1 (PON1) activity, and prolidase activity were evaluated in both cardiac and renal tissues. There was no significant difference in nitrogen oxide levels between the groups. However, cardiac and renal MDA were significantly higher and PON1 activity was markedly lower in the I/R groups compared with the control group (p<0.05). Although elevated prolidase activity was detected in both the cardiac and renal tissue of the I/R groups, only the sham group and Group V had significantly higher renal prolidase activity (p<0.05). Group V had significantly higher cardiac MDA, PON1, prolidase levels, and renal prolidase activity compared with the sham group (p<0.05). Significant improvement in renal MDA levels was only observed in Group III, and marked improvement was observed in the cardiac MDA levels of Group II when compared with the sham group (p<0.05). Thromboprophylactic agents appear to provide partial or prominent protection against I/R injury.

An alternative therapy for recurrent stasis ulcers in chronic venous insufficiency: venocuff.

Chronic venous insufficiency may cause stasis ulcers that significantly impact on the quality of life. Many methods have been described for preventing or treating these ulcers. However, stasis ulcers often recur as a result of continuing venous insufficiency. Here we report a 30-year-old male patient with chronic venous insufficiency. He was admitted to the hospital owing to recurrent stasis ulcers. He had a history of various flavonoid drug usage and compression therapies over the previous six years. Venous Doppler sonography revealed combined saphenofemoral and deep femoral venous insufficiency. Venocuff was applied to the prejunctional and postjunctional parts of the femoral vein and the saphenofemoral junction. The patient was discharged on the postoperative second day, and a low-molecular-weight heparin dressing composed of calcium alginate was applied to the ulcer wound for one week after the operation. The stasis ulcer wound was totally healed after one month. The patient was followed up six months after the operation, and no postoperative complications or new ulceration was observed. Recurrent stasis ulcers are major reasons for hospitalization in patients with chronic venous insufficiency. Venocuff application for reducing venous insufficiency may be a good option for adjunctive ulcer therapy and for preventing recurrences of the problem.