Topoisomerase I
- Rat lens aldose reductase (RLAR): IC₅₀ = 140.1 μM (45.2 μg/mL) [1]
- Human recombinant aldose reductase (HRAR): IC₅₀ = 154.2 μM (51.2 μg/mL) [1]
- DNA topoisomerase I: induces topoisomerase I‑mediated DNA cleavage at concentrations from 2.5 μM to 250 μM (no IC₅₀ reported); activity is lower than that of camptothecin [2]

- Groenlandicine showed RLAR inhibitory activity with an IC₅₀ of 45.2 μg/mL (140.1 μM). At 50 μg/mL, it exhibited 52.4% and 60.3% inhibition in duplicate experiments. [1]
- Groenlandicine also inhibited HRAR with an IC₅₀ of 51.2 μg/mL (154.2 μM). At 75 μg/mL, inhibition percentages were 76.9% and 69.2%; at 50 μg/mL, 53.9% and 53.9%; at 25 μg/mL, 23.1% and 15.4%. [1]
- In topoisomerase I‑mediated DNA cleavage assays, Groenlandicine induced nicked DNA in a concentration‑dependent manner from 2.5 μM to 250 μM. Quantitative densitometry showed that its cleavage activity was comparable to that of epiberberine but lower than that of camptothecin. [2]
- Groenlandicine did not induce topoisomerase II‑mediated DNA cleavage at concentrations up to 250 μM. [2]

- RLAR inhibition assay: The rat lens aldose reductase (RLAR) activity was measured using a modified method. The reaction mixture (1.0 mL) contained 100 mM sodium phosphate buffer (pH 6.2), 0.4 mM NADPH, 50 mM DL‑glyceraldehyde as substrate, and the test sample (dissolved in 100% DMSO, final concentration 10–100 μg/mL for extracts/fractions or 12.5–50 μg/mL for compounds). The enzyme reaction was started by adding the substrate, and the decrease in NADPH absorbance at 340 nm was recorded for 4 minutes. The inhibition percentage was calculated as [1 – (ΔA sample/min – ΔA blank/min) / (ΔA control/min – ΔA blank/min)] × 100. Quercetin (IC₅₀ 0.4 μg/mL) was used as a positive control. [1]
- HRAR inhibition assay: Human recombinant aldose reductase (HRAR, 0.4 unit) activity was examined according to the method of Nishimura et al. The reaction mixture (1.0 mL) contained 100 mM sodium phosphate buffer (pH 6.2), 0.15 mM NADPH, 10 mM DL‑glyceraldehyde, 5 μL of HRAR, and various concentrations of test samples (25–75 μg/mL dissolved in 100% DMSO). The decrease in NADPH absorption at 340 nm was measured over 1 minute. Inhibition percentage was calculated similarly to the RLAR assay, and quercetin was used as reference. [1]
- Topoisomerase I‑mediated DNA cleavage assay: The reaction buffer (50 mM Tris‑HCl pH 7.5, 100 mM KCl, 0.5 mM dithiothreitol, 0.5 mM EDTA, 30 μg/mL bovine serum albumin) containing 0.48 μg of supercoiled pUL402 DNA and the test compound (dissolved in DMSO/methanol) was mixed with calf thymus topoisomerase I. After incubation at 37 °C for 30 min, the reaction was terminated by adding 5% SDS and 2.5 mg/mL proteinase K, followed by another 30 min incubation at 37 °C. Samples were analyzed by 1.2% agarose gel electrophoresis in Tris‑borate‑EDTA buffer containing 0.1% SDS at 2 V/cm overnight. Gels were stained with thiolium bromide, and the amount of nicked DNA (indicating cleavable complex formation) was quantified by densitometry. Camptothecin was used as a positive control. [2]
- Topoisomerase II‑mediated DNA cleavage assay: The same reaction buffer was supplemented with 1 mM ATP and 10 mM MgCl₂. The reaction contained 0.48 μg of pUL402 DNA, calf thymus topoisomerase II, and the test compound. Incubation and termination were as described for topoisomerase I, and linear DNA (full‑length) was measured as an indicator of topoisomerase II‑mediated cleavage. VP‑16 was used as a positive control. [2]

[1]. Inhibitory activities of the alkaloids from Coptidis Rhizoma against aldose reductase. Arch Pharm Res. 2008 Nov;31(11):1405-12.

[2]. Inhibitors of DNA topoisomerase I and II isolated from the Coptis rhizomes. Planta Med. 1995 Oct;61(5):414-8.

- Groenlandicine, along with epiberberine and coptisine, was found to be an active aldose reductase inhibitor, whereas the major alkaloids berberine and palmatine showed no AR inhibition in this study. The presence of a dioxymethylene group in the D ring and the oxidized form of the dioxymethylene group in the A ring of protoberberine‑type alkaloids is partly responsible for the AR inhibitory activity. [1]
- In topoisomerase assays, Groenlandicine selectively induced topoisomerase I‑mediated DNA cleavage without affecting topoisomerase II, distinguishing it from berberrubine (which targets topoisomerase II). This selectivity suggests a structure‑activity relationship where specific substituents on the protoberberine core determine topoisomerase specificity. [2]

C19H16NO4

322.3346

321.1

38691-95-1

3084708

Orange to red solid

1.449

1

4

1

24

474

0

O1C([H])([H])OC2C([H])=C([H])C3=C([H])C4C5=C([H])C(=C(C([H])=C5C([H])([H])C([H])([H])[N+]=4C([H])=C3C1=2)O[H])OC([H])([H])[H]

PGIOBGCIEGZHJH-UHFFFAOYSA-O

InChI=1S/C19H15NO4/c1-22-18-8-13-12(7-16(18)21)4-5-20-9-14-11(6-15(13)20)2-3-17-19(14)24-10-23-17/h2-3,6-9H,4-5,10H2,1H3/p+1

16-methoxy-5,7-dioxa-1-azoniapentacyclo[11.8.0.03,11.04,8.014,19]henicosa-1(13),2,4(8),9,11,14,16,18-octaen-17-ol

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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

DMSO : ~1 mg/mL (~3.10 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.)