Exposure to various organic compounds including a number of environmental pollutants and drugs can cause cellular damages through metabolic activation of those compounds to highly reactive substances such as reactive oxygen species (ROS). Free radical induced lipid peroxidation is believed to be one of the major causes of cell membrane damage leading to a number of pathological situations [
1-
3]. Reports from our laboratory and other investigators have established that the industrial solvent, carbon tetrachloride (CCl
4) is a potent environmental hepatotoxin [
4-
7]. A number of recent reports clearly demonstrated that in addition to hepatic problems, CCl
4 also causes disorders in kidneys, lungs, testis and brain as well as in blood by generating free radicals [
8-
11]. Reports from Perez et al, Ogeturk et al and Churchill et al suggested that exposure to this solvent causes acute and chronic renal injuries [
12-
14]. In addition, reports on various documented case studies established that CCl
4 produces renal diseases in humans [
15,
16]. Extensive evidence demonstrated that
.CCl
3 and
.Cl are formed as a result of the metabolic activation of CCl
4, which in turn, initiate lipid peroxidation process. A known potent antioxidant, vitamin E, could protect CCl
4 induced liver injury indicating that oxidative stress is responsible for CCl
4 induced hepatic disorder in this particular model [
17,
18]. Studies also showed that various herbal extracts could protect organs against CCl
4 induced oxidative stress by altering the levels of increased lipid peroxidation, and enhancing the decreased activities of antioxidant enzymes, like superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) as well as enhanced the decreased level of the hepatic reduced glutathione (GSH) [
19,
20]. Knowledge on the protective mechanisms against toxin and drug induced organ-toxicities leads scientists to look for biologically active relevant compounds from herbal plants, which can possess intrinsic antioxidant activity and protect those organs from unwanted oxidative stress. In the modern medicine, plants occupy a significant birth as raw materials for some important drug preparations [
21-
23]. India is well known for a plethora of medicinal plants. The traditional Indian medicinal plants act as antiradicals and DNA cleavage protectors [
24]. These plants have also been considered to protect health, longevity, intelligence, immunosurveillance and body resistance against different infections and diseases.
Tephrosia purpurea [
25],
Silybum marianum [
26],
Picrorhiza kurroa [
27],
Cajanus indicus [
28,
29],
Phyllanthus niruri [
30-
32], etc. posses hepatoprotective property against different toxins and drugs induced hepatic disorders.
Terminalia arjuna (TA) is also an important medicinal plant widely used in the preparation of ayurvedic formulations for over three centuries primarily as a cardiac tonic in India [
33]. Clinical evaluation of this plant indicates that it can be of benefit in the treatment of coronary artery diseases, heart failure and possibly hypercholesterolemia [
34-
36]. It has also been found to be antibacterial and antimutagenic [
37-
39]. However, most of the beneficial works on this plant have been carried out on the alcoholic extract of its bark and very little is known about its role on toxin-induced either hepatic or renal disorders. In this particular study, protective role of aqueous extract of the bark of TA was evaluated against CCl
4-induced toxicity in the liver and kidney. Firstly, the radical scavenging activity of the extract was determined from its 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical quenching ability and the data were compared to those obtained from a known free radical scavenger, vitamin C. Secondly, the dose- and time-dependent effects of the extract against CCl
4-induced toxicity were evaluated by measuring the levels of the serum marker enzymes, glutamate pyruvate transaminase (GPT) followed by determining its effect on another serum marker enzyme, alkaline phosphatase (ALP) using optimum dose and time. Finally, hepatic and renal oxidant-antioxidant status was evaluated by measuring the levels of a) antioxidant enzymes SOD, CAT and GST; b) ROS scavenger GSH and c) extent of lipid peroxidation in both the livers as well as the kidneys in mice. In addition, study on the effect of a known antioxidant, vitamin E, was also included against CCl
4 induced hepatic and renal oxidative stress.