Protodioscin

Protodioscin is a steroidal saponin compound found in a number of plant species, most notably in the Tribulus, Trigonella Dioscorea and Trillium families.^[1][2][3] It is best known as the putative active component of the herbal aphrodisiac plant Tribulus terrestris.^[4][5]

Protodioscin

Clinical data
Routes of administration	Oral
ATC code	none
Legal status
Legal status	In general: legal
Identifiers
IUPAC name 26-O-beta-D-Glycopyranosyl-22-hydroxyfurost-5-ene-3beta,26-diol-3-O-beta-diglucorhamnoside
CAS Number	55056-80-9
PubChem CID	441891
ChemSpider	390467 Y
UNII	D0LC3PH24P
ChEBI	CHEBI:8588
Chemical and physical data
Formula	C51H84O22
Molar mass	1049.211 g·mol−1
3D model (JSmol)	Interactive image
SMILES C[C@H]1[C@H]2[C@H](C[C@@H]3[C@@]2(CC[C@H]4[C@H]3CC=C5[C@@]4(CC[C@@H](C5)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O[C@H]7[C@@H]([C@@H]([C@H]([C@@H](O7)C)O)O)O)O)O[C@H]8[C@@H]([C@@H]([C@H]([C@@H](O8)C)O)O)O)C)C)O[C@@]1(CC[C@@H](C)CO[C@H]9[C@@H]([C@H]([C@@H]([C@H](O9)CO)O)O)O)O
InChI InChI=1S/C51H84O22/c1-20(19-65-45-39(60)38(59)35(56)30(17-52)69-45)9-14-51(64)21(2)32-29(73-51)16-28-26-8-7-24-15-25(10-12-49(24,5)27(26)11-13-50(28,32)6)68-48-44(72-47-41(62)37(58)34(55)23(4)67-47)42(63)43(31(18-53)70-48)71-46-40(61)36(57)33(54)22(3)66-46/h7,20-23,25-48,52-64H,8-19H2,1-6H3/t20-,21+,22+,23+,25+,26-,27+,28+,29+,30-,31-,32+,33+,34+,35-,36-,37-,38+,39-,40-,41-,42+,43-,44-,45-,46+,47+,48-,49+,50+,51-/m1/s1 Y Key:LVTJOONKWUXEFR-UEZXSUPNSA-N Y
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Extracts of T. terrestris standardized for protodioscin content have been shown to produce proerectile effects in isolated tissues and aphrodisiac activity in several animal models.^[6][7] Protodioscin is thought to contribute to increased androgen receptor immunoreactivity in some tissues, likely as a secondary effect of elevated levels of endogenous androgens such as testosterone and dihydrotestosterone (DHT). This increase in androgen receptor immunoreactivity has been observed after administration of Tribulus terrestris extracts, but current evidence does not support the view that protodioscin acts primarily or directly by raising the density of androgen receptors; instead, it may enhance androgen receptor expression indirectly through its influence on androgen levels.^[8][9]

Although the precise mechanism has not been fully established, protodioscin has been reported to stimulate the release of nitric oxide in corpus cavernosum tissue,^[10] as well as to significantly increase circulating levels of testosterone, dihydrotestosterone, and dehydroepiandrosterone in animal studies.^[11] However, clinical studies in humans have not demonstrated consistent efficacy, and the therapeutic value of T. terrestris extracts remains controversial.^[12][13][14]