IngredientsProgenin III is a naturally occurring steroidal saponin belonging to the spirostanol (spirostane) structural class. Its recognized synonyms include Lilioglycoside D, Ophiopogonin C′, Polyphyllin V, and Prosapogenin D′1. It is also widely referred to in the scientific literature as Prosapogenin A. Prosapogenin A (also known as Progenin III and polyphyllin V) is a secondary steroidal saponin found in Dioscorea zingiberensis tubers, and is reported to have more superior pharmacological activities than its primary form, Protogracillin.
Its empirical molecular formula (Hill notation) is C₃₉H₆₂O₁₂, with a CAS registry number of 19057-67-1, and a molecular weight of 722.90 g/mol. The compound is registered in the NIH National Center for Advancing Translational Sciences (NCATS) Inxight Drugs database under the unique ingredient identifier (UNII) 220IAS5QO7, with the InChIKey HDXIQHTUNGFJIC-FOAHKCLGSA-N.
Progenin III is a naturally occurring spirostanol saponin. Steroidal saponins — of which progenin III is one — are among the most important secondary metabolites found in many plants, including those of the Dioscorea, Paris, and Trillium genera, and are divided into two major groups: furostanosides and spirostanosides. Progenin III falls into the spirostanoside (spirostanol) subclass. The glycosylated derivatives of diosgenin include dioscin, polyphyllin I, polyphyllin II, gracillin, deltonin, progenin III, trillin, and sprengerinin C; all of these steroidal saponins are modified by glycosylation at the C-3 position of the diosgenin backbone, and the glycosyl groups of dioscin, gracillin, polyphyllin II, deltonin, and progenin III are composed of L-rhamnose as well as D-glucose.
Progenin III has been identified in multiple plant genera from different geographical regions and botanical families:
In research and commercial reference-standard contexts, progenin III is available as a purified white to off-white crystalline powder. In laboratory-scale preparation, 117 g of crude progenin III was obtained from 160 g of substrate, and the crude product was purified with silica gel column to obtain 60.3 g progenin III of 93.4% purity. Both fat-soluble and water-soluble steroidal saponins are isolated from the rhizomes of D. nipponica using silica gel column chromatography, thin-layer chromatography, and high-performance liquid chromatography methods.
A key preparation advance involves enzymatic biotransformation: progenin III production from total steroidal saponins of Dioscorea nipponica Makino has been studied using crude enzyme from Aspergillus oryzae DLFCC-38; the crude enzyme converting total steroidal saponins into progenin III was obtained from the A. oryzae DLFCC-38 culture, with the strain cultured for 72 h at 30 °C with shaking at 150 rpm in 5% malt extract medium containing 2% extract of D. nipponica as the enzyme inducer. The crude enzyme converted total steroidal saponins into major progenin III with a high yield when the reaction was carried out for 9 h at 50 °C and pH 5.0 with 20 mg/ml of substrate.
Conventional preparation methods such as column chromatography and acidic hydrolysis are of very low efficiency and limited scale due to tedious procedures and large consumption of organic solvent; enzymatic hydrolysis of the abundant precursor Protogracillin has been developed as a more convenient alternative, with β-dextranase selected from four commercial enzymes as exhibiting the highest hydrolysis performance.
Progenin III occurs within plants that have deep roots in traditional East Asian medicine, though it must be noted that the historical traditions addressed whole-plant preparations rather than the isolated compound:
Dioscorea nipponica Makino is a perennial twining herb mainly distributed in the northeastern, northern, eastern, and central regions of China; traditionally, the rhizome has been commonly used by the Miao and Meng ethnic groups of China to treat rheumatoid arthritis, pain in the legs and lumbar area, Kashin-Beck disease, bruises, sprains, chronic bronchitis, cough, and asthma.
This famous traditional Chinese herbal medicine named Dioscorea nipponica Makino has been used traditionally for relieving cough and asthma, eliminating rheumatic aches, alleviating pain, and improving blood circulation. In more recent times, it has been used as an important industrial raw material for the synthesis of steroid hormones and saponin drugs for coronary heart disease.
The genus Dioscorea more broadly has been employed in both Asian and African traditional medical systems. The traditional medicinal uses of Dioscorea have been documented in Asian and African pharmacological systems; in Asia this genus is traditionally used to treat respiratory illnesses, rheumatism, diabetes, diarrhea, dysentery, and other conditions, while in Africa it has been used to treat HIV and ringworm.
Paris polyphylla Smith var. chinensis (Franch.) Hara has been used as a medicinal Paris for the prevention and treatment of cancers in China for thousands of years. Pharmacological studies have systematically characterized Paris polyphylla saponins as multifunctional agents with anti-inflammatory, analgesic, immunomodulatory, and antitumor activities, along with hemostatic, antimicrobial, and detoxifying properties. Toxicity evaluation studies have suggested that Rhizoma Paridis has slight liver toxicity; the dried rhizomes of P. polyphylla, P. polyphylla var. chinensis, and P. polyphylla var. yunnanensis were used to treat wound, bleeding, and related conditions. Paris polyphylla var. yunnanensis, used as a Chinese traditional medicine, is widely distributed in China; it has been widely used due to its antibiotic and anti-inflammatory properties and has additionally been used to treat liver cancer in particular.
Raphia vinifera is widely used to treat several diseases including digestive disorders, dysentery, and genitourinary infections. The boiled solution of the apical bud of Raphia vinifera is used to treat diseases such as genitourinary infections and gonorrhea in West Cameroon. Furthermore, most Raphia species are socio-economically important across tropical Africa; the palm sap/wine from Raphia palm has been reported to be used for the cure of malaria, measles, and jaundice, and for aiding in the flow of milk in nursing mothers. Palms (Arecaceae) are prominent elements in African traditional medicines.
It is important to note that these traditional uses refer to whole-plant preparations — decoctions, boiled solutions, and sap — and do not reflect the use of isolated progenin III as such. The identification of progenin III as a constituent of Raphia vinifera fruit came from modern phytochemical investigation rather than from documented traditional knowledge about the specific molecule.
Steroidal saponins are divided into two major groups: furostanosides and spirostanosides, and have been reported to possess a variety of pharmacological activities such as anti-platelet aggregation, anti-tumor, anti-diabetic, anti-hyperlipidemic, and anti-oxidative properties. Progenin III belongs specifically to the spirostanoside subclass, which generally features a spirocyclic ketal oxygen system in the side chain (rings E and F of the steroid skeleton).
The glycosylated derivatives of diosgenin — the aglycone sapogenin from which progenin III is derived — include dioscin, polyphyllin I, polyphyllin II, gracillin, deltonin, progenin III, trillin, and sprengerinin C. The glycosyl attachment pattern at C-3 (involving L-rhamnose and D-glucose) is critical for biological activity: structure–activity relationship studies on steroidal saponins have indicated that the cytotoxicity is highly sensitive to the change of their structures.
Progenin III is classified as a "secondary" saponin because it arises from enzymatic or acid-mediated hydrolysis of primary (furostanol) saponins present in plant rhizomes. Prosapogenin A (progenin III) is a secondary steroidal saponin in Dioscorea zingiberensis tubers, reported to have superior pharmacological activities compared to its primary form Protogracillin. This conversion from furanol precursor to spirostanol product accounts for the low natural abundance of progenin III and the interest in enzymatic biotransformation routes for its preparation.
In each of its botanical sources, progenin III occurs alongside a number of structurally related steroidal saponins that together constitute the pharmacologically active saponin profile of the whole plant extract. In Paris polyphylla, quantitative HPLC-MS/MS studies have identified at least nine co-occurring saponins including polyphyllin I, polyphyllin II, dioscin, polyphyllin VI, polyphyllin VII, polyphyllin H, gracillin, and polyphyllin S. Saponins and sapogenins are mainly responsible for most of the pharmacological effects of D. nipponica.
The most extensively studied pharmacological property of progenin III is its cytotoxicity against cancer cell lines. Top cytotoxic molecules identified from African plants include progenin III, identified from studies of the African flora and contributing to the library of natural products with anticancer potential. All existing evidence is preclinical — derived from in vitro cell-line experiments — and no human clinical trials have been conducted with isolated progenin III.
The most comprehensive published study on progenin III as an isolated compound was conducted by Mbaveng, Chi, Nguenang, Abdelfatah, and colleagues in 2020, published in Chemico-Biological Interactions (PMID 32454006). This study was aimed to investigate the cytotoxic potential of progenin III — described as a natural compound — on a broad range of cancer cell lines, including various sensitive and drug-resistant phenotypes.
The cytotoxicity and progenin III-induced autophagic, ferroptotic, and necroptotic cell death were evaluated by the resazurin reduction assay (RRA); spectrophotometric analysis of caspase activity was performed using the caspase-Glo assay; and flow cytometry was applied for cell cycle analysis (PI staining), apoptosis (annexin V/PI staining), mitochondrial membrane potential (MMP) (JC-1), and reactive oxygen species (ROS) (H₂DCFH-DA).
Key results: Progenin III and the reference molecule doxorubicin exerted cytotoxic effects towards the 18 cancer cell lines tested, including both animal and human cell lines; the IC₅₀ values obtained ranged from 1.59 μM (towards CCRF-CEM leukemia cells) to 31.61 μM (against the BRAF-V600E homozygous mutant SKMel-28 melanoma cells) for progenin III.
Normal sensitivity was achieved with CEM/ADR5000 cells and HCT116p53−/− adenocarcinoma cells respectively compared to their sensitive congeners CCRF-CEM cells and HCT116 p53+/+ cells. This finding — that drug-resistant sublines showed comparable sensitivity — was highlighted as a feature of potential clinical relevance. The authors concluded that progenin III is a potential anticancer molecule that deserves further investigation to develop a novel drug to combat malignant diseases including refractory cancers.
Evidence strength: This is an in vitro cell-line study only. No animal pharmacology or toxicology data and no human studies have been published for isolated progenin III. The evidence is preliminary.
The Mbaveng et al. (2020) study characterized three distinct cell-death pathways triggered by progenin III:
The general mechanism by which steroidal saponins cause cytotoxicity relates to their amphiphilic nature and ability to interact with membrane cholesterol, disrupting lipid bilayer integrity and activating intracellular signaling cascades. The kind of tri-sugars attached to the C-3 hydroxyl group of the steroid backbone supports cytotoxicity, and the ratio of lipophilic to hydrophilic sites in the molecular structure plays a decisive role, giving a further mechanism for saponin-induced hemolysis and cytotoxicity.
A 2024 study by Liu Y. and colleagues (Cell Death & Disease, 2024 Aug 13;15(8):586) identified a distinct anticancer mechanism for progenin III / Prosapogenin A in anaplastic thyroid cancer (ATC) cells. Prosapogenin A (progenin III) induces GSDME-dependent pyroptosis of anaplastic thyroid cancer through vacuolar ATPase (V-ATPase) activation-mediated lysosomal over-acidification. Neutralization of lysosomal lumen acidification or inhibition/knockdown of V-ATPase subunits attenuated progenin III-induced lysosomal damage, pyroptosis, and growth inhibition of ATC cells, highlighting the critical role for lysosomal acidification and lysosomal membrane permeabilization (LMP) in progenin III's anticancer effects; the compound may act as a V-ATPase agonist targeting lysosomal acidification, presenting a new potential therapeutic option for ATC treatment.
Evidence strength: In vitro study only. No in vivo validation is yet published for this specific mechanism.
Prosapogenin A (progenin III) is reported to induce apoptosis in human cancer cells in vitro via inhibition of the STAT3 signaling pathway and glycolysis; it is one of the important monomers of Chonglou extract with good anticancer effect; it showed good in vitro antitumor effect on colon cancer cells; and compared with oxaliplatin, a commonly used anti-tumor compound, Prosapogenin A has strong anti-tumor properties on colon cancer cells and has the potential to become an effective anti-colon cancer compound.
Evidence strength: In vitro cell-line data; no published clinical or animal data specific to isolated progenin III in colon cancer at this time.
A particularly noteworthy in vitro finding relates to progenin III's activity in multidrug-resistant (MDR) cell lines. An in vitro experimental study demonstrated that progenin III exhibited favorable antiproliferative activity against 18 human and animal cancer cell lines, including those with a drug-resistance phenotype, such as the P-glycoprotein (P-gp)-overexpressing subline CEM/ADR5000 cells from CCRF-CEM human T-lymphoblast leukemia cells. The CEM/ADR5000 subline overexpresses P-gp (encoded by ABCB1), a major efflux pump responsible for clinical multidrug resistance. The ability of progenin III to evade this resistance mechanism — at least at the cellular level — is a scientifically significant preliminary observation requiring validation in animal models and eventual clinical study.
These steroidal saponins were reported to possess a variety of pharmacological activities such as anti-platelet aggregation, anti-tumor, anti-diabetic, anti-hyperlipidemic, and anti-oxidative effects. While these activities are well-documented for the saponin class and for many structurally related compounds in Dioscorea and Paris species, specific published evidence for each of these activities as directly attributable to isolated progenin III is limited. The vast majority of class-level evidence relates to crude extracts, total saponin fractions, or structurally related but distinct saponins (e.g., dioscin, gracillin, polyphyllin I/II).
Progenin III is a quantified constituent of the pharmacologically active Paris polyphylla saponin (PPS) mixture studied in anti-cancer research. Extracts of Paris polyphylla rhizomes — prepared using solvents ranging from polar (aqueous, alcoholic) to nonpolar (petroleum ether) — demonstrate broad bioactivity, exhibiting antioxidant, antimicrobial, and antitumor effects primarily attributable to their PPS content. However, these mixture-level findings cannot be attributed solely to progenin III; polyphyllin I, II, VI, and VII are among the most studied individual saponins in these preparations. Treatment with Paris polyphylla steroidal saponin fractions (PRS) at doses of 2.5, 5.0, and 7.5 mg/kg significantly inhibited tumor volume and weight in Lewis tumor-bearing C57BL/6 mice, with inhibition rates of 26.49 ± 17.30%, 40.32 ± 18.91%, and 54.94 ± 16.48%, respectively. Progenin III (Paris V) was identified as one of nine components in those fractions but its individual contribution was not isolated in that study.
Based on the available peer-reviewed evidence, the body systems and conditions progenin III has been associated with — primarily in preclinical research — are as follows:
Pharmacokinetic data for isolated progenin III in humans do not exist in the published literature. The only available pharmacokinetic data come from rat studies of Paris polyphylla extract (not isolated progenin III), and they reveal important limitations for oral administration:
After oral administration of P. polyphylla extract to rats, the Cmax values of polyphyllin I, polyphyllin II, progenin III, polyphyllin IV, gracillin, and polyphyllin were all less than 10 μg/L; the bioavailabilities of all nine components were less than 1%; all the compounds were hydrolyzed by intestinal flora and were predominantly distributed in the liver and lungs; and multiple administrations did not accumulate in the body.
These findings indicate that orally administered steroidal saponins from Paris polyphylla — including progenin III — are substantially hydrolyzed by gut microflora and have extremely low systemic bioavailability (<1%) in rats. The pharmacokinetic behavior of intravenous versus oral progenin III, its metabolites, tissue distribution in other species, and any human pharmacokinetic parameters remain unstudied.
Because of progenin III's extremely low natural abundance in source plants, several strategies have been developed to obtain research quantities:
No human dosage data exist. Published dosage information is restricted to in vitro assays:
No established therapeutic dose, tolerated dose, or pharmacologically effective dose in any human population has been described in the scientific literature for isolated progenin III.
Progenin III is described as having low hemolytic activity, which is cited as a favorable property relative to other spirostanol saponins and is one reason it has been highlighted as a potential candidate for anti-cancer therapy. This is relevant because saponins as a class are known to disrupt red blood cell membranes through their amphiphilic structure; the relative lowness of hemolytic activity in progenin III compared to structurally related saponins is a pharmacologically significant property, though the absolute hemolytic risk in therapeutic contexts has not been clinically characterized.
The correlation between membrane toxicity and the reduction in surface tension has been revealed, and the ratio of lipophilic and hydrophilic sites in the molecular structure appears to play a decisive role, giving a mechanism for saponin-induced hemolysis and cytotoxicity.
Toxicity evaluation studies have suggested that Rhizoma Paridis (from which progenin III can be isolated) has slight liver toxicity. This signal is attributed to the saponin fraction of the plant as a whole; its relevance to isolated progenin III specifically has not been established or refuted in published studies.
The bioavailabilities of steroidal saponins from P. polyphylla, including progenin III, were all less than 1% after oral administration in rats; all compounds were hydrolyzed by intestinal flora. The products of intestinal hydrolysis of steroidal saponins and their potential biological or toxic effects have not been fully characterized for progenin III specifically.
No toxicological data — acute, sub-chronic, chronic, reproductive, or developmental — specific to isolated progenin III in humans or in standardized animal toxicology models have been published in peer-reviewed sources retrievable by this review. The cytotoxic potency observed in cancer cell lines (IC₅₀ values in the low micromolar range) underscores the need for selectivity profiling against normal cell types before any human use could be contemplated.
Progenin III is not recognized as a standalone dietary supplement ingredient by any major regulatory body (FDA, EFSA, EMA, WHO) and does not appear in official pharmacopeial monographs as an isolated compound. It is currently available commercially only as a research reference standard for laboratory use.
The scientific literature on progenin III is in an early, exploratory stage. The totality of directly attributable evidence consists of a small number of in vitro cytotoxicity studies and one mechanistic study in anaplastic thyroid cancer cells. The compound is recognized as a potential anticancer molecule that deserves further investigations to develop a novel drug to combat malignant diseases including refractory cancers.
Critical evidence gaps include: (1) in vivo animal efficacy and toxicity studies using isolated progenin III; (2) human pharmacokinetic studies; (3) identification of specific molecular targets beyond caspase-3/7, STAT3, glycolysis pathways, and V-ATPase; (4) selectivity data comparing cytotoxicity in cancer versus normal human cell types; and (5) any clinical trial data whatsoever. Notably, the specific necroptosis mechanism has not yet been fully elucidated.
Commercially available Paris polyphylla saponins (RPS) — preparations that include polyphyllin V (progenin III) — have been studied for broad bioactivity; extracts of Paris polyphylla rhizomes demonstrate antioxidant, antimicrobial, and antitumor effects primarily attributable to their PPS content. However, disentangling the individual contribution of progenin III from the activity of multi-component saponin mixtures remains a central challenge for future research.
Health conditions that Progenin III may help support.
Body systems that Progenin III may help support.
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