Rat sperm immobilisation effects of a protein from Ricinus communis (Linn.): an in vitro comparative study with nonoxynol-9.

Previous study conducted in our department showed that 50% ethanolic extract of the root of Ricinus communis possess reversible antifertility effect and a 62-kDa protein (Rp) from this extract is responsible for the antifertility effects. In this study, we compared the spermicidal effect of this Rp with nonoxynol-9 (N-9) in vitro. The sperm immobilisation studies showed that 100 µg ml(-1) of Rp was able to immobilise the sperms completely within 30 s. Sperm revival test revealed that the spermicidal effect was irreversible. There was also a significant reduction in sperm viability and hypo-osmotic swelling in Rp and N-9 treated groups in comparison with the control. In Rp and N-9 treated groups, the number of acrosome-reacted cells was found to be high and also caused agglutination of the spermatozoa, indicating the loss of intactness of the plasma membrane, which was further supported by the significant reduction in the activity of membrane bound 5'-nucleotidase, acrosomal acrosin. In short, the protein Rp possesses spermicidal activity in vitro and its effects are similar to that of nonoxynol 9.

Spermicidal action of a protein isolated from ethanolic root extracts of Achyranthes aspera: an in vitro study.

A previous study conducted in our department, showed that 50% ethanolic extract of the roots of Achyranthes aspera possess spermatotoxic effects. Preliminary studies also revealed that the active principle may be a protein. In this study a 58 kDa Achyranthes protein (Ap) was isolated from Achyranthes aspera using standard protocols and their effects on the rat sperm was studied in vitro in comparison with nonoxynol-9 (N-9). The sperm immobilization studies showed that about 150 µg of Ap was able to immobilize sperms completely within seconds at a lower concentration than N-9 (250 µg). The sperm revival test revealed that the spermicidal effect was irreversible. There was also a significant reduction in sperm viability and hypo-osmotic swelling in the Ap-treated and N-9 treated groups in comparison to the control. In the Ap and N-9 treated groups the number of acrosome reacted cells were found to be high and it also caused agglutination of the sperms indicating the loss of intactness of the plasma membrane which was further supported by the significant reduction in the activity of membrane bound 5' nucleotidase and acrosin enzyme. Hence this study showed that the protein isolated from the roots of Achyranthes aspera possess spermicidal activity in vitro and can act as a spermicide similar to that of nonoxynol 9. Ap also possessed spermicidal activity against human sperms in vitro.

Effects on spermatogenesis in swiss mice of a protein isolated from the roots of Ricinus communis (Linn.) (Euphorbiaceae).

This study was aimed to evaluate the effect on spermatogenesis of a 62 kDa protein (Rp) isolated from 50% ethanolic extract of the root of Ricinus communis in mice. A dose response study in mice revealed that 25mg/kg body weight/day was the most effective dose. Swiss strain mature male mice of 30 days old were divided into two group namely control and Rp treated (25mg/kg body weight/day). The study showed that sperm motility and count were decreased significantly in the treated group as compared to the control. The fertility index of the treated groups was reduced by 100%. The activity of HMG Co A reductase and cholesterol were increased significantly in the treated group. The testicular activities of 3ßHSD, 17ßHSD, glucose 6-phosphate dehydrogenase and malic enzyme and the level of serum testosterone were decreased significantly in the treated group. The expression of 3ßHSD and 17ßHSD were decreased and the expression of StAR increased significantly in the treated group as compared to the control. Proteolytic digestion of the native protein with trypsin and chymotrypsin showed that the proteolytic cleavage did not affect the spermicidal action of Rp. Hence this study can be concluded that Rp impaired spermatogenesis in vivo by suppressing the production of testosterone.

Antiperoxidative and antiinflammatory effect of Sida cordifolia Linn. on quinolinic acid induced neurotoxicity.

Sida cordifolia is a plant belonging to the Malvaceae family used in many ayurvedic preparations. This study aimed at assessing the effects of ethanolic extract of Sida cordifolia root on quinolinic acid (QUIN) induced neurotoxicity and to compare its effect with the standard drug deprenyl in rat brain. Rats were divided into six groups: (1) control group (2) QUIN (55 microg/100 g bwt/day) (3) 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (4) Deprenyl (100 microg/100 g bwt/day) (5) QUIN (55 microg/100 g bwt/day) + 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (6) QUIN (55 microg/100 g bwt/day) + Deprenyl (100 microg/100 g bwt/day). At the end of the experimental period a status of lipid peroxidation products, protein peroxidation product, activities of the scavenging enzymes and the activities of the inflammatory markers were analyzed. Results revealed that the lipid peroxidation products decreased and the activities of the scavenging enzymes increased significantly in the brain of the plant extract treated group, deprenyl treated group and also in the coadminstered groups. The activities of markers of inflammatory responses such as cyclooxygenase and lipoxygenase were found to be significantly increased in the QUIN treated rats and this was decreased upon the administration of plant extract and deprenyl. In short, the study revealed that 50% ethanolic extract of Sida cordifolia has got potent antioxidant and antiinflammatory activity and the activity is comparable with the standard drug deprenyl.