TY - JOUR
T1 - Exposure of tilapia pituitary cells to saponins
T2 - Insight into their mechanism of action
AU - Levavi-Sivan, Berta
AU - Hedvat, Rachel
AU - Kanias, Tamir
AU - Francis, George
AU - Becker, Klaus
AU - Kerem, Zohar
N1 - Funding Information:
This research was supported by a grant from the University of Hohenheim.
PY - 2005/1
Y1 - 2005/1
N2 - Cell permeation and durable effects of triterpenoidal saponin preparations from soybean (SbS), Quillaja saponaria Molina (QsS) and Gypsophila paniculata (GypS), were studied. A concentration-dependent change in hemolysis rates was observed when cells were incubated with QsS or GypS, but not with SbS. Dose dependence was also observed for the leakage of lactate dehydrogenase (LDH; MW 142,000) and of Luteinizing Hormone (LH; MW 35,000) from tilapia pituitary dispersed cells. Exposure of pituitary fragments to a combination of GnRH and GypS or QsS, resulted in a significantly high release of LH. GypS were shown to be more potent in inducing hemolysis of human RBC's and LH release from tilapia pituitary fragments. Interestingly, tilapia pituitary fragments treated with QsS were able to secrete LH in a characteristic manner, in response to a second Gonadotropin Releasing Hormone (GnRH) pulse, while fragments exposed to GypS did not respond to the second hormone pulse. The rapid recovery of pituitary fragments after the removal of QsS, may suggest a rearrangement of membranes rather than pore formation as the mechanism of action of QsS. Understanding the structural features underlying the reversible rearrangement of membranes and the lack of hemolysing activity by specific saponins may lead to the development of novel bioactive drugs.
AB - Cell permeation and durable effects of triterpenoidal saponin preparations from soybean (SbS), Quillaja saponaria Molina (QsS) and Gypsophila paniculata (GypS), were studied. A concentration-dependent change in hemolysis rates was observed when cells were incubated with QsS or GypS, but not with SbS. Dose dependence was also observed for the leakage of lactate dehydrogenase (LDH; MW 142,000) and of Luteinizing Hormone (LH; MW 35,000) from tilapia pituitary dispersed cells. Exposure of pituitary fragments to a combination of GnRH and GypS or QsS, resulted in a significantly high release of LH. GypS were shown to be more potent in inducing hemolysis of human RBC's and LH release from tilapia pituitary fragments. Interestingly, tilapia pituitary fragments treated with QsS were able to secrete LH in a characteristic manner, in response to a second Gonadotropin Releasing Hormone (GnRH) pulse, while fragments exposed to GypS did not respond to the second hormone pulse. The rapid recovery of pituitary fragments after the removal of QsS, may suggest a rearrangement of membranes rather than pore formation as the mechanism of action of QsS. Understanding the structural features underlying the reversible rearrangement of membranes and the lack of hemolysing activity by specific saponins may lead to the development of novel bioactive drugs.
KW - Membrane
KW - Pituitary
KW - Pores
KW - Quillaja
KW - Rearrangement
KW - Saponin
KW - Soybean
KW - Tilapia
UR - http://www.scopus.com/inward/record.url?scp=15744380545&partnerID=8YFLogxK
U2 - 10.1016/j.cca.2005.01.002
DO - 10.1016/j.cca.2005.01.002
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
C2 - 15792626
AN - SCOPUS:15744380545
SN - 1532-0456
VL - 140
SP - 79
EP - 86
JO - Comparative Biochemistry and Physiology Part - C: Toxicology and Pharmacology
JF - Comparative Biochemistry and Physiology Part - C: Toxicology and Pharmacology
IS - 1
ER -