Swainsonine targets α-mannosidase, a key enzyme involved in the processing of N-linked glycoproteins. As a reversible, active-site directed inhibitor, it binds to the active site of the enzyme and prevents the hydrolysis of mannose residues from glycoproteins. By inhibiting α-mannosidase, it disrupts the normal processing of N-linked glycans, which can affect protein folding, trafficking, and function. Its antimetastatic effects are likely mediated through its ability to alter the glycosylation of cell surface proteins involved in cell adhesion and migration. Its immunomodulatory activity suggests effects on immune cell function.

Swainsonine (0-40 μM; 12 h) demonstrates antiproliferative action in U251 and LN444 cells [2]. Swainsonine (30 μM; 12 h) stimulates cell engraftment and cell cycle induction in G2/M phase, and lowers CyclinD1 and Swainsonine (30 μM; 12 h) reduces tumor cell migration and right side [2].
In vitro, Swainsonine is a potent inhibitor of α-mannosidase at concentrations of 5-10 mM. Its activity is typically assessed by measuring the inhibition of α-mannosidase activity in enzyme assays using purified enzyme or cell lysates and a chromogenic substrate. The compound has been shown to have antimetastatic, antiproliferative, and immunomodulatory activity in various cell-based assays. Its ability to alter glycosylation patterns has been demonstrated in cancer cell lines, where it affects cell adhesion, migration, and invasion. Its antiproliferative effects suggest potential for cancer therapy.

In mice, cisplatin plus swansonine (1 mg/kg; intraperitoneal injection; twice daily for 10 days) increased antitumor effectiveness [3].
In vivo, Swainsonine has been studied for its potential therapeutic applications in cancer and viral infections. Its antimetastatic activity has been demonstrated in animal models of cancer, where it inhibits tumor metastasis. Its immunomodulatory effects suggest potential for enhancing immune responses. However, specific in vivo efficacy data are limited. The compound's ability to inhibit α-mannosidase and alter glycosylation may have systemic effects, though its toxicity profile is a concern. Comprehensive in vivo studies are needed to fully evaluate its therapeutic potential.

In vitro non-cell enzyme assays for Swainsonine involve measuring the inhibition of α-mannosidase activity using purified enzyme. The compound is incubated with the enzyme and a chromogenic substrate (e.g., p-nitrophenyl-α-D-mannopyranoside), and the release of p-nitrophenol is measured spectrophotometrically. IC₅₀ values are calculated from dose-response curves. The compound's binding affinity to α-mannosidase can be assessed using surface plasmon resonance or isothermal titration calorimetry. These assays provide quantitative data on the compound's potency and mechanism of inhibition.

Cell Viability Assay[2]
Cell Types: U251, LN444 cells
Tested Concentrations: 0, 10, 20, 30, 40 µM
Incubation Duration: 12 hrs (hours)
Experimental Results: Inhibits cell viability in a dose-dependent manner and is not cytotoxic to normal brain cells.

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Cell cycle analysis[2]
Cell Types: U251 Cell
Tested Concentrations: 30 µM
Incubation Duration: 12 hrs (hours)
Experimental Results: Induced cell cycle arrest in G2/M phase.

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Apoptosis analysis [2]
Cell Types: U251 Cell
Tested Concentrations: 30 µM
Incubation Duration: 12 h
Experimental Results: Cell apoptosis was induced, and the expression of cleaved-Caspase-3 and cleaved-Caspase-9 was Dramatically increased.
In vitro cell-based assays for Swainsonine use various cancer cell lines to study its antiproliferative and antimetastatic effects. Cells are treated with varying concentrations of the compound, and parameters such as cell viability (MTT or CCK-8 assays), cell migration (wound healing or transwell assays), and cell invasion (matrigel invasion assays) are assessed. Glycosylation patterns are analyzed by lectin-binding assays or Western blotting. Its immunomodulatory effects can be studied in immune cells by measuring cytokine production and cell proliferation. These studies help to characterize the compound's cellular mechanism of action.

Animal/Disease Models: 87 60-day-old male C57BL/6 mice [3]
Doses: 1 mg/kg (cisplatin; 0.25 mg/kg, ip, every other day for 10 days)
Route of Administration: ip; twice (two times) daily, The results lasted for ten days: the ascites volume of mice was Dramatically diminished by 63.5%, and the percentage of cells in G0/G1, S and G2 phases was Dramatically diminished.
In vivo animal studies for Swainsonine would likely employ models of cancer metastasis, such as experimental metastasis models or orthotopic tumor models. The compound is administered orally or intraperitoneally, and parameters such as tumor growth, metastasis, and survival are assessed. Tumor tissues are analyzed for markers of glycosylation, cell adhesion, and apoptosis. Its immunomodulatory effects can be studied in models of immune function. Pharmacokinetic studies in these models provide information about the compound's absorption, distribution, metabolism, and excretion.

Swainsonine has a molecular weight of 173.21 g/mol and a molecular formula of C₈H₁₅NO₃. Its chemical name is (1S,2R,8R,8aR)-octahydro-1,2,8-indolizinetriol. The compound is soluble in DMSO (10 mg/ml), ethanol (10 mg/ml), and water (8 mg/ml). It should be stored at -20°C to maintain its stability. As a small, polar molecule, it is expected to have reasonable oral bioavailability. Detailed pharmacokinetic parameters such as half-life, volume of distribution, and clearance have not been extensively characterized.

Toxicity Summary
Swanesenine inhibits the activity of glycoside hydrolases, particularly N-linked glycosylation enzymes. Inhibition of Golgi mannosidase II and other α-mannosidases leads to the accumulation of atypical heterozygous glycoproteins and oligosaccharides, as these substances cannot be processed normally. This also results in intracellular vacuolation. (L1248, A3092, A3093)
The toxicity profile of Swainsonine is a concern, as it is a potent inhibitor of α-mannosidase and can cause significant biological effects. Ingestion of plants containing Swainsonine, such as locoweed, can cause toxicosis in livestock, characterized by neurological symptoms, weight loss, and reproductive problems. The compound's effects on glycosylation can affect multiple organ systems. As a research compound, Swainsonine is not intended for human therapeutic use without further safety evaluation. Standard laboratory safety precautions should be followed when handling the compound.

[1]. Inhibition of lysosomal alpha-mannosidase by swainsonine, an indolizidine alkaloid isolated from Swainsona canescens. Biochem J. 1980 Nov 1;191(2):649-51.

[2]. Swainsonine represses glioma cell proliferation, migration and invasion by reduction of miR-92a expression. BMC Cancer. 2019 Mar 19;19(1):247. doi: 10.1186/s12885-019-5425-7.

[3]. Increased antitumor efficacy by the combined administration of swainsonine and cisplatin in vivo. Phytomedicine. 2011 Sep 15;18(12):1096-101.

Swainsonine is an indolithidine alkaloid isolated from the plant Swainsonine, with three hydroxyl substituents at positions 1, 2, and 8. It possesses antitumor activity, immunoadjuvant activity, EC 3.2.1.114 (mannosyl oligosaccharide 1,3-1,6-α-mannosidase) inhibitory activity, and plant metabolite activity. It is a potent α-mannosidase inhibitor derived from Swainsonine. Swainsonine also exhibits anti-metastatic, anti-proliferative, and immunomodulatory activities. It has been reported to exist in Slafractonia leguminicola, Oxytropis glabra, and other organisms with relevant data. Swanesenine is a plant toxin found in legumes (Fabaceae, Astragalus, and Swainsona) and certain fungi (Metarhizium anisopliae, Rhizoctonia solani). It is known to cause a potentially fatal central nervous system disease in livestock called "hysteria," a significant cause of economic losses in the livestock industry. Swanesenine, along with another bioactive compound from Rhizoctonia solani—slavamine—may cause a disease called "drooling" in livestock that ingest contaminated feed. (L1248, A3092) Swanesenine is an indolithidine alkaloid from the plant Swainsonine, a potent α-mannosidase inhibitor. It also possesses anti-metastatic, anti-proliferative, and immunomodulatory activities.

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Mechanism of Action
Tridolgosir competitively inhibits α-mannosidase II (αMII), an enzyme responsible for processing the N-linked sugars of newly synthesized glycoproteins, which are transported to the cell surface via the Golgi apparatus. The resulting highly branched sugar structures can bind to lectin-phytohemagglutinin (L-PHA) and are expressed in different types of tumors, leading to a metastatic phenotype. This metastatic phenotype is associated with increased tumor invasiveness in animals and can lead to other human malignancies. Inhibition of αMII reduces carbohydrates bound to L-PHA, thereby decreasing the activity of tumor-invasive and metastatic cells, slowing tumor growth, and increasing the content of "mixed" carbohydrates on the cell surface. Mixed carbohydrates may enhance cytokine activation in lymphocytes, thereby increasing the sensitivity of tumors to lymphokine-activated cells and natural killer cells.
Swainsonine is an indolizidine alkaloid and a potent, reversible inhibitor of α-mannosidase. It exhibits antimetastatic, antiproliferative, and immunomodulatory activity. The compound is found in plants such as Swainsona species and locoweed (Astragalus spp.). It has been studied for its potential therapeutic applications in cancer and viral infections. Not approved for clinical use; intended for research purposes only.

C8H15NO3

173.2096

173.105

72741-87-8

51683

Light yellow to brown solid powder

1.38±0.1 g/cm3

353.3±21.0 °C at 760 mmHg

144-145 ºC

209.7±20.7 °C

0.0±1.8 mmHg at 25°C

1.609

-0.79

3

4

0

12

176

4

C1C[C@H]([C@@H]2[C@@H]([C@@H](CN2C1)O)O)O

FXUAIOOAOAVCGD-WCTZXXKLSA-N

InChI=1S/C8H15NO3/c10-5-2-1-3-9-4-6(11)8(12)7(5)9/h5-8,10-12H,1-4H2/t5-,6-,7-,8-/m1/s1

(1S,2R,8R,8aR)-1,2,3,5,6,7,8,8a-octahydroindolizine-1,2,8-triol

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~10 mg/mL (~57.73 mM)
Ethanol : ~10 mg/mL (~57.73 mM)
H2O : ~3.57 mg/mL (~20.61 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)