Hepatoprotective effect of carob against acute ethanol-induced oxidative stress in rat.

The present study was undertaken to determine whether subacute treatment with aqueous extract of carob (Ceratonia siliqua L.) pods (AECPs) protects against ethanol (EtOH)-induced oxidative stress in rat liver. Animals were divided into four groups: control, carob, EtOH and EtOH + carob. Wistar rats were intraperitoneally pretreated with AECP (600 mg/kg body weight (bw)) during 7 days and intoxicated for 6 h by acute oral administration of EtOH (6 g/kg bw) 24 h after the last injection. We found that acute administration of EtOH leads to hepatotoxicity as monitored by the increase in the levels of hepatic marker aspartate aminotransferase and alanine aminotransferase as well as hepatic tissue injury. EtOH also increased the formation of malondialdehyde in the liver, indicating an increase in lipid peroxidation and depletion of antioxidant enzyme activities as superoxide dismutase, catalase and glutathione peroxidase. Subacute carob pretreatment prevented all the alterations induced by EtOH and returned their levels to near normal. Importantly, we showed that acute alcohol increased hepatic and plasmatic hydrogen peroxide and free iron levels. The carob pretreatment reversed EtOH effects to near control levels. These data suggest that carob could have a beneficial effect in inhibiting the oxidative damage induced by acute EtOH administration and that its mode of action may involve an opposite effect on plasma and tissue-free iron accumulation. Indeed, carob can be offered as a food additive to protect against EtOH-induced oxidative damage.

Inhibitory Effects of Two Varieties of Tunisian Pomegranate (Punica granatum L.) Extracts on Gastrointestinal Transit in Rat.

The present study was undertaken to determine whether total and methanol juice extracts of two Tunisian Pomegranate (Punica granatum L.) varieties (Garsi and Gabsi) protect against diarrhea as well as their effects on gastrointestinal transit (GIT) in healthy rats. In this respect, male Wistar rats were used and divided into control- and pomegranate-treated groups. The antidiarrheal activity was evaluated using the castor oil-induced diarrhea method and the GIT was assessed using charcoal meal. Our results showed that total and methanol P. granatum juice extracts produced a significant dose-dependent protection against castor oil-induced diarrhea. Pomegranate extracts and juice also decreased the GIT significantly and dose dependently. Importantly, the Garsi variety appeared to be more effective than the Gabsi variety on these two parameters. These findings suggest that pomegranate extracts have a potent antidiarrheal property in rats confirming their efficiency in the Tunisian traditional medicine.

Effects of dates pulp extract and palm sap (Phoenix dactylifera L.) on gastrointestinal transit activity in healthy rats.

The current study was performed to measure the chemical composition and the effects of dates pulp extract and palm sap on gastrointestinal transit (GIT) activity in healthy adult rats. In this respect, male Wistar rats fasted for 24 hours were used and received per orally (p.o.) sodium chloride (NaCl) (0,9%) (control group) or various doses of dates pulp extract (150 and 300 mg/kg, body weight [b.w.]) and palm sap (0.4 and 4 mL/kg, b.w.). Two other groups of rats (batch tests) received, respectively, clonidine (an alpha-2 adrenergic agonist, 1 mg/kg, b.w.) and yohimbine (an alpha-2 adrenergic antagonist, 2mg/kg, b.w.). Chemical analysis showed that the dates pulp extract is more rich in sugars and minerals, especially potassium and sucrose, as compared with palm sap composition. On the other hand, in vivo study showed that the aqueous dates pulp extract significantly, and dose dependently, increased the GIT activity while the palm sap slightly increased it. Moreover, a converse effect has been observed using clonidine (decreased 68%) and yohimbine (increased 33%) on the GIT activity. These findings suggest that dates pulp extract and palm sap have a stimulating effect on GIT activity in rats and confirm their use in traditional Tunisian medicine for the treatment of constipation.

Chronic exposure to mercuric chloride during gestation affects sensorimotor development and later behaviour in rats.

The current study was performed to assess the effects of inorganic mercury (mercuric chloride - HgCl(2)) on the development of offsprings from intoxicated-mother during pregnancy. In this respect, pregnant rats were chronically treated with HgCl(2) at 50 ppm (Hg50) and 100 ppm (Hg100) in drinking water. After parturition, maternal behaviour was recorded during 30 min at 1st to 6th postnatal day (Pnd). The development of their offspring was studied during the first 17 days after birth. Sensorimotor development of pups was measured by different tests: rooting reflex, vibrissae placing response, righting reflex, negative geotaxis, suspension test and rotating grid. Two month after birth, the anxiety of offspring was tested using the elevated plus maze test. Our results indicate that mercury treatment significantly reduced the nursing and increased the time out the nest or drinking and eating. We also showed that prenatal exposure to HgCl(2) decreased weight gain. Importantly, the rooting reflex, the development of the vibrissae placing response, the righting reflex, the grip strength and the negative geotaxis behaviour were delayed in the offspring of dams treated with Hg50, the delay being more severe with Hg100. We also found a decrease in anxiety in adulthood. Cross-fostering test support the direct toxic effects of mercury.