Does hyperbaric oxygen therapy reduce the effects of ischemia on colonic anastomosis in laparoscopic colon resection?

BACKGROUND: An increase in intra-abdominal pressure causes a decrease in the splanchnic blood flow and the intramucosal pH of the bowel, as well as increasing the risk of ischemia in the colon. The aim of the present study is to evaluate the effect of hyperbaric oxygen therapy (HBOT) on the ischemia caused by laparoscopy in colonic anastomosis in an experimental model of laparoscopic colonic surgery. MATERIALS AND METHODS: We divided 30 male Wistar albino rats into three groups: Group A was the control (open colon anastomosis); Group B received LCA (laparoscopic colon anastomosis); while Group C received both LCA and HBOT. Each group contained ten animals. We placed Group C (LCA and HBOT) in an experimental hyperbaric chamber into which we administered pure oxygen at 2.1 atmospheres absolute 100% oxygen for 60 min for ten consecutive days. RESULTS: The anastomotic bursting pressure value was found to be higher in the open surgery group (226 ± 8.8) (Group A). The result for Group C (213 ± 27), which received HBOT, was better than that for Group B (197 ± 27). However, there was no statistically significant difference between Group B and Group C. Group A showed better healing than the other groups, while significant differences in the fibroblast proliferation scores were found between Groups A and B. In terms of tissue hydroxyproline levels, a significant difference was found between Groups A and B and between Groups A and C, but not between Groups B and C. CONCLUSIONS: HBOT increases the oxygen level in the injured tissue. Although HBOT might offer several advantages, it had only a limited effect on the healing of colonic anastomosis in rats with increased intra-abdominal pressure in our study. KEY WORDS: Anastomosis, Colon, Hyperbaric Oxygen Treatment, Oxidative Stress.

The role of carnitine in preventing renal damage developed as a result of infrarenal aortic ischemia-reperfusion.

BACKGROUND: This study was designed to use carnitine for preventing deposition of end products of lipid peroxidation in rat models in the prevention of ischemia-reperfusion (IR) damage frequently seen following operations of infrarenal abdominal aorta (AA). METHODS: Forty male rats of Sprague-Dawley type were evenly (n = 8) randomized to five groups: sham laparotomy (SHAM), carnitine control (CC), aortic IR (AIR), AIR + low-dose carnitine (AIR+LDC), and AIR + high-dose carnitine (AIR+HDC). RESULTS: Compared to other groups, serum creatinine levels of AIR group were significantly higher. Also tissue malondialdehyde (MDA) levels of AIR group were significantly higher compared to SHAM, CC, and AIR+HDC groups. In histopathological examination, although tubular necrosis atrophy and tubular degeneration observed in AIR group showed regression with low-dose carnitine, tubular necrosis atrophy, tubular degeneration, glomerular damage, and vascular congestion thrombosis decreased with high-dose carnitine. Total score of histological damage was significantly higher in AIR, AIR+LDC, and AIR+HDC groups compared to SHAM and CC groups. Moreover, total score of histological damage was significantly lower in AIR+HDC group than AIR+LDC group. CONCLUSIONS: In this study, we showed carnitine can partially prevent renal damage in infrarenal AIR models of rats. This result may open new prospects to us in the prevention of renal IR damage during surgery of aorta.

[Healing of osteochondral defects in canine knee with avocado/soybean unsaponifiables: a morphometric comparative analysis]. / Avokado/soya fasülyesinin sabunlasmayan ekstresi verilen köpeklerin dizlerinde osteokondral defekt iyilesmesi: Bir karsilastirmali morfometrik analiz.

OBJECTIVES: This study aims to determine the effects of avocado/soybean unsaponifiables (ASU) on healing in a canine osteochondral defect model. MATERIALS AND METHODS: Fourteen dogs were included in the study and randomly divided into two groups. Two osteochondral defects were produced in the lateral aspect of the trochlear groove of the knee joint. The treatment group (group 1; n=7) was given 300 mg ASU capsules every three days whereas the control group (group 2; n=7) was given a normal diet. Animals were then allowed to ambulate normally until euthanasia at 15 weeks. The knees were dissected and the trochlear grooves with defects were removed for pathological examination. The amount of regenerated tissue was determined quantitatively using image analysis and the tissue content was evaluated semi-quantitatively using Safranin-O and Masson trichrome histochemical stains. Transforming growth factor beta (TGF-beta) increase was evaluated semi-quantitatively with immunohistochemical staining methods. RESULTS: Morphometric analysis revealed a significantly more immature repair tissue in group 1 (p<0.002). Both collagen and chondral tissue content of the regenerated tissue were significantly increased in group 1 (p<0.002). Compared to that in group 2, cartilage tissue in group 1 showed a much more marked immunostaining reaction of TGF-beta. CONCLUSION: Avocado/soybean unsaponifiables treatment stimulates the healing of the osteochondral defects in canine knee possibly by increasing TGF-beta in the tissues.

The protective effect of avocado soybean unsaponifilables on brain ischemia/reperfusion injury in rat prefrontal cortex.

OBJECT: We investigated the protective effects of avocado/soybean unsaponifiables (ASU) on the prefrontal cortex (PFC) after global brain ischemia/reperfusion (I/R) injury in rats. METHODS: Rats were randomly divided into three experimental groups as follows: Group I was control rats, Group II was ischemia rats, Group III was Isch + ASU rats. Brain ischemia was produced via four-vessel occlusion model. These processes followed by reperfusion for 30 min for both II and III groups. Rats were sacrificed and their brains were removed immediately. Malondialdehyde (MDA) and superoxide dismutase (SOD) were measured in left PFC, levels of TNF-α concentration were measured in the plasma. The number of apoptotic neurons was assayed in histological samples of the right PFC. RESULTS: MDA and TNF-α levels as well as the number of apoptotic neurons were observed to have decreased significantly in Group III compared to Group II, while SOD activities have been found to have increased significantly in Group III in comparison to Group II, significantly. CONCLUSIONS: We think that ASU might have an antioxidant and neuroprotective effects in brain I/R injured rats.

The neuroprotective effect of fish n-3 fatty acids in the hippocampus of diabetic rats.

INTRODUCTION: Diabetes mellitus may lead to functional and structural changes in the brain. Fish oil is a rich source of n-3 essential fatty acids (EFA) such as eicosapentaenoic and docosahexoenoic acids. We examined the neuroprotective effects of fish n-3 EFA in the hippocampus of diabetic rats. MATERIALS AND METHODS: Nineteen adult male rats were divided into three groups. Group I (control; n = 6) was fed a normal rat diet. Group II (diabetic; n = 6) was fed a normal rat diet and streptozotocin (STZ) was administered to induce diabetes mellitus. Group III (n-3 + diabetic; n = 7) was fed a normal rat diet and fish n-3 EFA (Marincap, 0.4 g/kg/day) for 8 weeks and STZ was administered to induce diabetes mellitus. The levels of malondialdehyde (MDA) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus after the animals were sacrificed. The right hemisphere was completely blocked. The sections were stained with Cresyl Violet and apoptotic neurons were counted in the hippocampus. RESULTS: The levels of MDA and activities of SOD and CAT increased in diabetic rats compared to control rats. However, the levels of MDA and activities of SOD and CAT decreased in n-3 + diabetic rats compared to diabetic rats. Also, the number of apoptotic neurons increased in diabetic rats compared to control rats and decreased in n-3 + diabetic rats compared to diabetic rats. CONCLUSIONS: Fish n-3 EFA reduces oxidative stress and induces apoptotic changes in the hippocampus of STZ-diabetic rats. The addition of fish n-3 EFA to diets may be useful to prevent functional and structural changes to cerebral centers due to diabetes mellitus.

The protective effect of fish n-3 fatty acids on cerebral ischemia in rat prefrontal cortex.

This study presents neuroprotective effects of fish n-3 EFA on the prefrontal cortex after cerebral ischemia and reperfusion. Eighteen rats divided into three groups. Group A rats were used as control. Cerebral ischemia and reperfusion was produced in rats either on a standard diet (Group B) or a standard diet plus fish n-3 EFA for 14 days (Group C). The malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD) and catalase (CAT) were measured and the number of apoptotic neurons was counted. The levels of MDA and activities of SOD increased in Group B rats as compared to Group A rats, and decreased in Group C rats as compared to Group B rats. The activities of CAT increased in Group C as compared to Group B rats. The number of apoptotic neurons in the prefrontal cortex was lower in Group C as compared to Group B rats.

Oral administration of avocado soybean unsaponifiables (ASU) reduces ischemic damage in the rat hippocampus.

BACKGROUND: The beneficial effects of avocado/soybean unsaponifiables (ASU) are known as an antiarthritic agent. This experimental study presents the effects of ASU on oxidant/antioxidant systems and the number of apoptotic neurons of hippocampal formation after ischemia and reperfusion. METHODS: Eighteen rats were divided into three equal groups: group I rats were used as controls; group II rats were fed with standard diet and group III rats were fed with standard diet plus ASU pills for 10 days. One day after electrocauterization of bilateral vertebral arteries for groups II and III, bilateral common carotid arteries were occluded for 30 min and then reperfused for 30 min. After these procedures, rats of all groups were sacrificed. The levels of malondialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus. The number of apoptotic neurons was counted by Tunel method in histological samples of right hippocampus. RESULTS: MDA and NO levels increased in group II compared with group I rats (p = 0.002, p = 0.015). In group III, MDA and NO levels decreased as compared to group II (p = 0.041, p = 0.002). SOD and CAT activities increased in group III as compared to group II rats (p = 0.002, p = 0.002). The number of apoptotic neurons was lower in group III as compared to group II rats. CONCLUSIONS: The present findings suggest that ASU could decrease oxidative stress and apoptotic changes in ischemic rat hippocampus. Dietary supplementation of ASU may be beneficial to prevent or ameliorate ischemic cerebral vascular disease.

The protective effect of fish n-3 fatty acids on cerebral ischemia in rat hippocampus.

Reactive oxygen species (ROS) have been implicated in the pathogenesis of cerebral injury after ischemia-reperfusion (I/R). Fish n-3 essential fatty acids (EFA), contain eicosapentaenoic acids (EPA) and docosahexoenoic acids (DHA), exhibit antioxidant properties. DHA is an important component of brain membrane phospholipids and is necessary for the continuity of neuronal functions. EPA prevents platelet aggregation and inhibits the conversion of arachidonic acid into thromboxane A(2) and prostaglandins. They have been suggested to be protective agents against neurological and neuropsychiatric disorders. In this study, the neuroprotective effects of fish n-3 EFA on oxidant-antioxidant systems and number of apoptotic neurons of the hippocampal formation (HF) subjected to cerebral I/R injury was investigated in Sprague-Dawley rats. Six rats were used as control (Group I). Cerebral ischemia was produced by occlusion of both the common carotid arteries combined with hypotension for 45 min, followed by reperfusion for 30 min, in rats either on a standard diet (Group II) or a standard diet plus fish n-3 EFA (Marincap((R)), 0.4 g/kg/day, by gavage) for 14 days (Group III). At the end of procedures, the rats were sacrificed and their brains were removed immediately. The levels of malonedialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in left HF. In addition, the number of apoptotic neurons was counted by terminal transferase dUTP nick end labelling (TUNEL) assay in histological samples of the right HF. We found that SOD activities and MDA levels increased in Group III rats compared with Group II rats. On the other hand, CAT activities and NO levels were found to be decreased in Group III rats compared with Group II rats. Additionally, the number of apoptotic neurons was lower in Group III in comparison with Group II rats. The present findings suggest that fish n-3 EFA could decrease the oxidative status and apoptotic changes in ischemic rat hippocampal formation. Dietary supplementation of n-3 EFA may be beneficial to preserve or ameliorate ischemic cerebral vascular disease.