Hypericum Humifusum Leaves Attenuates Hepatic Ischemia-Reperfusion Injury in a Rat Model.

INTRODUCTION: Effective prevention strategies require specific actions during the different phases of ischemia-reperfusion (I-R) injury. The objective of our study is to evaluate the effect of aqueous extract of Hypericum humifusum leaves (HHL) on liver I-R model in Rat. MATERIAL AND METHODS: Animals were subjected to 90 min of hepatic ischemia followed by reperfusion (120 min). HHL extract (25 mg/mL/kg) was injected 15 min before reperfusion. To evaluate the effect of HHL extract on I-R, we have monitored transaminases levels, Malondialdehyde (MDA) concentration, histological lesions (apoptosis and necrosis) and compared the results to a reference oxidant vitamin E. RESULTS: The determination of total phenol extracts of HHL was 59.91 ± 0.35 mg of Gallic Acid/g dry plant material with higher antioxidant activity (91.73% ± 1.67) compared to vitamin E (87.42%). Using aqueous extract of HHL, we noted a significant decrease of AST and ALT [1129 UI (585/1995) and 768 UI (335/1375)] compared to no-treated group [5,585.5 UI (5,035/12,070) and 8,099.5 UI (5,040/12,326)] as a decrease in MDA content [85.7% protection (50.9/91.5)]. HHL extract reduce the damage induced by I-R of 48.7% (27/48.7) and 96.1% (95.7/96.5) for necrosis and apoptosis lesions respectively. CONCLUSION: HHL aqueous extract have potential to protect liver from the damage effect induced by I-R better than vitamin E solution.

Protective effect of Ulva lactuca extract during hepatic cold preservation in rats.

Introduction In recent years, many marine resources have drew attention in the research for bio-active compounds to develop new drugs and health foods. (1) Marine algae are now considered as a rich source of antioxidants (2). It is known that seaweeds contain numerous bioactive substances that have the ability to lower cholesterol, reduce blood pressure, promote healthy digestion; and antioxidant activity (3). Natural antioxidants are interesting compounds due to their properties which help prevent oxidative stress (4), among other potentially beneficial actions. For instance, several biological effects have been attributed to flavonoids, such as anti-tumoral, anti-inflammatory, anti-ischemic and anti-aggregate plaquetary activities. These activities are believed to be in part related to the antioxidant properties of the compounds, namely in scavenging radical oxygen species (ROS). (5, 6) The cold ischemia constitute a situation of oxidative stress in touch with liberation of oxygenated radicals, these situations incited the researchers to find means for the improvement of the conservation of organs allowing to prolong the durations of the cold ischemia of certain organs (in particular the liver) with conservation of the maximum functional value. However, the constant efforts led by the teams of transplantation to develop transplants, the conservation of organs remains a problem to be resolved. (7) Conservation solution of organ appears as being a stemming to remedy the fatal effects of the ischemia-reperfusion. For our part, we think that seaweeds have not delivered their secrets and yet especially that the marine environment of the Tunisian coast still remains little exploited in spite of the big variety of the fauna and the flora of the coast. We envisage in this work, to study a sort of seaweed collected on the Tunisian quotation in the region of "Chott Meriem" (North West of Tunisia). The purpose of our work is to estimate the capacity of extracts stemming from the green seaweed Ulva lactuca to improve the conservation solution of organs against the hepatic effects of ischemia.

Animal model of liver ischemia reperfusion: biochemical and histological evaluation.

INTRODUCTION: During last years, significant progress was made in the comprehension of the hepatic lesions after Ischemia-Reperfusion episode in order to improve the Results in practice clinical. AIM: To avoid or reduce the damage induced by Ischemia-Reperfusion, we developed a model of hepatic Ischemia-Reperfusion with variable periods of reperfusion from 0 to 24 hours.  METHODS: Our study related to rats Wistar males.  Six various groups were studied: the first reference group (without neither ischemia and reperfusion), the second group with ischemia of 90 min and without reperfusion and the 3end , 4end, 5end and 6end groups in addition to ischemia, underwent a reperfusion of 30 min, 2h, 6h and 24h respectively.  The damage of hepatic Ischemia-Reperfusion was evaluated by a biochemical test based on the proportioning of transaminases and an anatomopathologic study by optical microscopy for the determination of the degree of hepatic attack.  RESULTS: The RESULTS obtained seem to show an aggravation of the liver lesions and an increase in the plasmatic rates of AST and ALT in relation with the duration of the reperfusion.  Indeed, the maximum of damage was observed after 2 hours of reperfusion. We observed a reduction in the lesions after 6h and 24h of reperfusion.  CONCLUSION: Our work enabled us to describe a simple model of hepatic Ischemia-Reperfusion with functional, biochemical and anatomopathologic tests.