Studies on Na,K-ATPase inhibition revealed that oleandrin had an IC50 (nM) of 620. Oleandrin's inhibition of Na,K-ATPase indicates that it may impede sodium pump action in order to cause toxicity [1]. Undifferentiated CaCO-2 cells showed sensitivity to oleandrin at doses ranging from 0.2 to 25 nM, with an IC50 of 8.25 nM. In contrast, differentiated CaCO-2 cells could only achieve a maximum growth inhibition of 20% when treated with oleandrin at concentrations as high as 25 nM [2].

Studies were conducted on oleandrin's effects on glioma growth in vivo. Hence, the right striatum of SCID or C57BL/6 mice was transplanted with human U87MG (5×104), U251, GBM19 (5×105), or murine (syngeneic) GL261 (7.5×104) cells, respectively. , and ten days later, oleandrin was administered intraperitoneally every day for seven days. In vivo glioma cell models in mice and humans exhibit a dose-dependent reduction in tumor growth due to oleandrin. High doses of oleandrin (3 mg/kg) were fatal in both models, as would be expected based on the known lethal dose in rodents. The survival time of mice injected with U87MG cells was significantly extended from 32.6±1.4 days to 53.8±9.6 days (n=5-11; p<0.01, log-rank test) by oleandrin doses below the lethal dose (0.3 mg/kg) and from 23.37±1.2 days to 34.38±3.3 days (n=5-11; p<0.01, log-rank test) for mice injected with GL261 cells [3].

Absorption, Distribution and Excretion
Pharmacokinetic studies were conducted on the cardiac glycoside (3)H oleandrin of Anvirzel, administered intravenously (40 μg/kg) orally (80 μg/kg). Oleandrin was rapidly absorbed after oral administration (reaching Cmax in 20 minutes), but its elimination half-life (2.3 ± 0.5 hours) was longer than that after intravenous administration (0.4 ± 0.1 hours). The AUC0-∞ values after intravenous and oral administration were 24.6 ± 11.1 and 14.4 ± 4.3 ng·hr/mL, respectively, with an oral bioavailability of approximately 30%. Following intravenous administration, the concentration of oleandrin in the liver was approximately twice that in the heart or kidney tissues. Oleandrin (the aglycone of oleandrin) was also found in these tissues. Five minutes after injection, over 60% of the total radioactivity in the liver was derived from oleandrin, while 28% of the administered dose was present in the form of oleandrin. Twenty-four hours after injection, 8% of the total radioactivity was excreted in the urine, including oleandrin (4.4% of the injected dose) and oleandrin (1.9%). 66% of the injected radioactivity was present in the feces, with equal levels of oleandrin and oleandrin. The uptake of oleandrin in brain tissue after intraperitoneal injection of oleandrin (3 mg/kg) or oleander extract (700 mg/kg) was investigated. The oleandrin content in brain tissue after injection of the extract was higher than after injection of the same dose of oleandrin, as determined by liquid chromatography-tandem mass spectrometry (LC/MS/MS). Data suggest that certain components of the oleander extract may enhance the transport of oleandrin across the blood-brain barrier. The toxicity observed in rabbits treated with oleander infusion or decoction was attributed to the oleandrin content in various organs. The highest concentrations of oleandrin were found in the heart, stomach, kidneys, and blood, while it was not detected in the lungs and brain.

Toxicity Summary
Identification and Uses: Oleandrin is a solid. It is a cardiac glycoside found in oleander (Nerium oleander) and yellow oleander (Thevetia peruviana). Human Exposure and Toxicity: Ingestion of oleandrin can cause nausea, vomiting, abdominal pain, diarrhea, arrhythmia, and hyperkalemia. Typical symptoms of oleander poisoning include dilated pupils, accompanied by dizziness, convulsions, coma, and bradycardia. Accidental ingestion can lead to arrhythmia and even death. Several fatal and non-fatal cases of poisoning have been reported. Animal Studies: In areas where oleander is distributed, oleander poisoning should be included in the differential diagnosis of equines exhibiting abdominal pain, especially when azotemia or arrhythmia is detected simultaneously. Ecotoxicity studies: Exposure of the freshwater spotted grouper (C. punctatus) to sublethal doses of oleandrin for 24 and 96 hours significantly altered the activities of total protein, total free amino acids, nucleic acids, glycogen, pyruvate, lactate, and proteases, phosphatases, alanine aminotransferase, aspartate aminotransferase, and acetylcholinesterase in liver and muscle tissue.

---

Interactions
Oleandrin poisoning is common in children, and this plant extract is used in traditional Chinese medicine. Its toxicity is caused by oleandrin and its deglycosylated metabolite, oleandrinogen. Bufotalin and bufotoxin (toad cardiotoxin) are widely used in traditional Chinese medicine, such as in toad venom and deer antler velvet. There have been reports of severe poisoning from bufotalin after consuming toad soup. Utilizing the structural similarity between these toxins and digoxin, we demonstrated that these compounds in the blood can be rapidly detected by digoxin fluorescence polarization immunoassay. The cross-reactivity of these compounds with digoxin assays is much lower. For example, when 10 μg/mL of oleandrin was added to drug-free serum, we observed a digoxin equivalent concentration of 127.7 ng/mL, compared to only 2.4 ng/mL. Digibind neutralizes all the cardiotoxins studied, as evidenced by the significant decrease in free toxin concentrations. When 0, 10.0, 25.0, 50.0, 100, and 200 μg/mL of digoxin binder were added to aliquots of serum containing 50.0 μg/mL oleandrin, the average free concentrations were 30.6, 23.3, 16.0, 10.7, 7.8, and 5.5 μg/mL, respectively. Similarly, in a sample containing 50.0 μg/mL oleandrin (total concentration: 36.2 ng/mL), the free concentration was 14.5 ng/mL (digoxin equivalent) without the addition of a digoxin binder, while the free concentration was 5.4 ng/mL with the addition of 200 μg/mL digoxin binder. In another sample containing 500 ng/mL bufalin (total concentration: 156.9 ng/mL), the free bufalin concentration was 8.6 ng/mL without the addition of digebin, while no free bufalin was detected after the addition of 100.0 μg/mL digebin. Since this neutralization effect can also occur in vivo, digebin may be helpful in treating patients exposed to these toxins. Given the potential role of interleukin-8 (IL-8) in inflammation, angiogenesis, tumorigenesis, and metastasis, and the involvement of different cell types (especially neutrophils and macrophages) in these processes, regulating IL-8-mediated biological responses is crucial. The evidence presented in this report indicates that the cardiac glycoside oleandrin inhibits NF-κB activation in macrophages induced by interleukin-8 (IL-8), formyl peptide (FMLP), epidermal growth factor (EGF), or nerve growth factor (NGF), but has no inhibitory effect on NF-κB activation induced by interleukin-1 (IL-1) or tumor necrosis factor (TNF). Oleandrin inhibits IL-8-induced NF-κB-dependent gene expression, but has no inhibitory effect on TNF-induced NF-κB-dependent gene expression. Oleandrin inhibits the binding of IL-8, EGF, or NGF, but has no inhibitory effect on the binding of IL-1 or TNF. Oleandrin reduced IL-8 binding by nearly 79% without altering its affinity for the IL-8 receptor, and this inhibitory effect on IL-8 binding was also observed in isolated cell membranes. IL-8 antibodies, anti-IL-8 receptor antibodies, or protease inhibitors could not prevent the inhibitory effect of oleandrin on IL-8 binding. Phospholipids significantly protected the oleandrin-mediated inhibition of IL-8 binding, thereby restoring IL-8-induced NF-κB activation. Oleandrin altered membrane fluidity, which could be detected by the dose-dependent reduction in microviscosity parameters and the binding of diphenylhextriene (a lipid-binding fluorophore). In summary, our results indicate that oleandrin modulates the IL-8 receptor by altering membrane fluidity and microviscosity, thereby inhibiting IL-8-mediated biological responses in multiple cell types. This study may contribute to the modulation of IL-8-mediated biological responses associated with inflammation, metastasis, and angiogenesis. Oleandra (Nerium oleander) poisoning is a common health problem in many parts of the world. Oleander toxicity is caused by oleandrin and its aglycone metabolite oleandrin. Activated charcoal is an effective gastrointestinal cleanser that can limit the absorption of ingested toxins. A relatively new clay product, Bio-Sponge, with its active ingredient di-tri-octahedral montmorillonite, has also been recommended for adsorbing bacterial toxins in the gastrointestinal tract. Bio-Sponge has been used to prevent the absorption of oleander toxins in the gastrointestinal tract of livestock, but the adsorption effects of activated charcoal and Bio-Sponge on oleandrin and oleandrin have not been studied. This study conducted an in vitro experiment comparing the adsorption effects of three commercially available adsorbents: Bio-Sponge, ToxiBan granules, and ordinary activated charcoal. The results showed that ToxiBan granules had the strongest adsorption capacity, followed by ordinary activated charcoal, and then Bio-Sponge. Bio-sponge failed to adsorb oleandrin and oleandrin expected to be present in the gastrointestinal tract of poisoned animals. Based on this in vitro study, products containing activated charcoal were more effective than those containing di-tri-octahedral montmorillonite in binding oleander toxins and purifying the gastrointestinal tract. However, whether these adsorbents can improve clinical outcomes in oleander poisoning animals or humans remains to be evaluated. Cardiac glycosides, such as digoxin and ouabain, have previously been shown to have selective cytotoxicity against tumor cells rather than normal cells. Furthermore, these drugs have also been shown to be effective radiosensitizers. In this study, we investigated the relative radiosensitizing potential of oleandrin. Oleandrin is a cardiac glycoside found in an extract of a plant called Anvirzel, which recently completed a Phase I clinical trial as a novel anticancer drug. Data showed that oleandrin enhanced the radiation sensitivity of PC-3 human prostate cancer cells; the enhancement factor was 1.32 at a cell viability of 0.1. The extent of the radiosensitizing effect depended on the duration of cell exposure to the drug before radiotherapy. While only 1 hour of cell exposure to the drug was required to observe the radiosensitizing effect of oleandrin, 24-hour pretreatment significantly enhanced this effect. The sensitivity of PC-3 cells to oleandrin and radiation-induced apoptosis depends on caspase-3 activation. Caspase-3 activation is most pronounced when cells are simultaneously exposed to oleandrin and radiation. Inhibition of caspase-3 activation using Z-DEVD-FMK eliminates the oleandrin-induced radiation-enhanced response, indicating that both oleandrin and radiation induce apoptosis in the PC-3 cell line through a caspase-3-dependent mechanism. Ceramide (N-acetyl-D-sphingosine) is a second messenger in cell signaling, inducing transcription factors such as nuclear factor-κB (NF-κB) and activator protein-1 (AP-1), and participating in inflammation and apoptosis. Drugs that can inhibit these transcription factors may help block tumorigenesis and inflammation. Oleandrin (trans-3,4',5-trihydroxystilbene) is a polyphenolic cardiac glycoside extracted from oleander leaves and has been used for many years to treat heart disease in Russia and China. We investigated the effects of oleandrin on ceramide-induced NF-κB and AP-1 activation and apoptosis. Oleandrin blocked ceramide-induced NF-κB activation. This oleandrin-mediated NF-κB inhibition was not limited to human epithelial cells; it was also observed in human lymphocytes, insect cells, and mouse macrophages. NF-κB inhibition occurred concurrently with AP-1 inhibition. Oleandrin enhanced ceramide-induced generation of reactive intermediates, lipid peroxidation, cytotoxicity, caspase activation, and DNA fragmentation. Oleandrin showed no activity in primary cells. The anticancer, anti-inflammatory, and growth-regulating effects of oleandrin may be partly attributed to its inhibition of NF-κB and AP-1 activation and its enhancement of apoptosis.

---

Non-human toxicity values
LD50: Human-like intravenous injection 300 μg/kg

[1]. Inhibition of Na,K-ATPase by oleandrin and oleandrigenin, and their detection by digoxin immunoassays. Clin Chem. 1996 Oct;42(10):1654-8.

[2]. Cellular location and expression of Na+, K+-ATPase α subunits affect the anti-proliferative activity of oleandrin. Mol Carcinog. 2014 Apr;53(4):253-63.

[3]. The Glycoside Oleandrin Reduces Glioma Growth with Direct and Indirect Effects on Tumor Cells. J Neurosci. 2017 Apr 5;37(14):3926-3939.

Therapeutic Uses
This study aimed to investigate the mechanism of action and differential cytotoxic effects of Anvirzel, an extract from Nerium oleander (Apocynaceae), and its derivative oleandrin on human, canine, and mouse tumor cells. Cells were treated with different concentrations of Anvirzel (1.0 ng/mL to 500 μg/mL) or oleandrin (0.01 ng/mL to 50 μg/mL) under continuous and pulsed/recovery culture conditions. The cytotoxicity of these compounds was then determined. Both Anvirzel and oleandrin induced cell death in human cancer cells, but not in mouse cancer cells; oleandrin exhibited higher cytotoxic efficacy than Anvirzel. Treatment of canine oral cancer cells with Anvirzel resulted in a moderate cellular response with some abnormal metaphase and cell death. Based on these results, we conclude that the effects of Anvirzel and oleandrin are species-specific. When testing the anticancer efficacy of a novel compound, it is necessary to use not only mouse cancer cells but also a variety of cancer cells, including human cancer cells. Oleandrin, extracted from the leaves of oleander (Nerium oleander), has been shown to have anti-inflammatory and tumor cell growth-inhibiting effects. The evidence presented in this article suggests that oleandrin may have anti-tumor promoting effects. We investigated the effects of topical application of oleandrin on conventional and novel biomarkers of skin tumor promotion induced by the CD1 mouse skin tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Applying oleandrin (2 mg per mouse) to the mouse skin for 30 minutes, followed by application of TPA (3.2 nmol per mouse), significantly inhibited TPA-mediated skin edema and hyperplasia, epidermal ornithine decarboxylase (ODC) activity, and ODC and cyclooxygenase-2 (COX-2) protein expression in a time-dependent manner. To identify novel biomarkers for skin tumor promotion, we found that TPA application to mouse skin induced early increases in phosphatidylinositol 3-kinase (PI3K) expression, Akt phosphorylation at threonine 308, and nuclear factor κB (NF-κB) activation. Applying oleandrin to mouse skin before TPA significantly reduced TPA-induced PI3K expression and Akt phosphorylation, and inhibited NF-κB activation. NF-κB is a eukaryotic transcription factor that plays a crucial role in regulating the expression of specific genes involved in inflammation, apoptosis, and cell proliferation. Our Western blot analysis revealed that oleandrin application to mouse skin inhibited TPA-induced NF-κB and IKKα activation, as well as IκBα phosphorylation and degradation. Our data suggest that oleandrin may be a potent anti-tumor promoter because it inhibited multiple biomarkers of TPA-induced tumor promotion in an in vivo animal model. One could envision using chemopreventive agents such as oleandrin in emollients or patches for the chemoprevention or treatment of skin cancer. NF-κB is a ubiquitous and well-defined protein responsible for regulating complex physiological processes. Under certain physiological and pathological conditions, it plays a crucial role in controlling cellular signaling in the body. NF-κB has multiple functions, including regulating the gene expression of genes encoding pro-inflammatory cytokines (e.g., IL-1, IL-2, IL-6, TNF-α), chemokines (e.g., IL-8, MIP-1α, MCP-1, RANTES, eosinophil chemokines), adhesion molecules (e.g., ICAM, VCAM, E-selectin), inducible enzymes (COX-2 and iNOS), growth factors, some acute-phase proteins, and immune receptors. These molecules play a key role in controlling most inflammatory processes. Because NF-κB is an important and highly attractive drug target for treating a variety of inflammatory diseases, including arthritis, asthma, and autoimmune diseases, much effort has been devoted to finding compounds that can selectively interfere with this pathway over the past decade. In recent years, a large number of plant-derived substances have been evaluated as potential inhibitors of the NF-κB pathway. These compounds are diverse, including lignans (manasantin, (+)-sosenestine, (-)-sosenestine methyl ether), sesquiterpenes (costunolone, patenolide, tripterygium lactone, tripterygium alcohol A), diterpenes (excanine, carmebacoline), triterpenes (avesin, oleandrin), and polyphenols (resveratrol, epigallocatechin gallate, quercetin). In this short review, we will explore the medicinal chemistry of these compounds and their inhibitory effects on NF-κB.
/EXPL THER/ Chemotherapy and radiotherapy for cancer face two major challenges: tumor resistance to treatment (chemotherapy resistance and radiotherapy resistance) and nonspecific toxicity to normal cells. Many plant-derived polyphenols have been extensively studied due to their potential chemopreventive properties and pharmacological safety. These compounds include genistein, curcumin, resveratrol, silymarin, phenethyl caffeate, flavonol pyridinol, emodin, green tea polyphenols, piperine, oleandrin, ursolic acid, and betulinic acid. Recent studies have shown that these plant polyphenols may enhance the sensitivity of tumor cells to chemotherapy drugs and radiotherapy by inhibiting pathways leading to treatment resistance. Furthermore, these substances have been found to protect cells from treatment-related toxicities. This article will explore how these polyphenols protect normal cells and enhance the sensitivity of tumor cells to treatment.
/EXPL THER/ The main active ingredient of the plant candidate drug PBI-05204 (supercritical CO₂ extract of oleander) is the cardiac glycoside oleandrin. PBI-05204 exhibits potent anticancer activity and is currently undergoing a Phase I clinical trial for the treatment of patients with solid tumors. We have previously demonstrated that oleandrin, which is structurally related to oleandrin, has significant neuroprotective effects in brain slices and whole-body animal models of ischemic injury. However, oleandrin itself is not suitable as a drug development candidate, and the FDA-approved cardiac glycoside digoxin cannot cross the blood-brain barrier. This article reports that both oleandrin and the whole extract of PBI-05204 significantly protect nerve tissue damaged by hypoxia and hypoglycemia (such as ischemic stroke). More importantly, we found that the neuroprotective activity of PBI-05204 was maintained for several hours after delayed administration following hypoxia and hypoglycemia treatment. Our evidence suggests that the neuroprotective activity of PBI-05204 is mediated by oleandrin and/or other cardiac glycoside components, but other non-cardiac glycoside components of PBI-05204 may also contribute to the observed neuroprotective activity. Finally, we directly demonstrated using a novel in vivo neuroprotective model that the protective activities of both oleandrin and PBI-05204 can penetrate the blood-brain barrier. In summary, these findings suggest that PBI-05204 has clinical application potential in the treatment of ischemic stroke and the prevention of related neuronal death.

C32H48O9

576.72

576.329

465-16-7

11541511

White to off-white solid powder

1.26

693.7±55.0 °C at 760 mmHg

250ºC

217.2±25.0 °C

0.0±4.9 mmHg at 25°C

1.567

2.3

2

9

6

41

1080

13

C[C@H]1[C@@H]([C@H](C[C@@H](O1)O[C@H]2CC[C@]3([C@@H](C2)CC[C@@H]4[C@@H]3CC[C@]5([C@@]4(C[C@@H]([C@@H]5C6=CC(=O)OC6)OC(=O)C)O)C)C)OC)O

JLPDBLFIVFSOCC-XYXFTTADSA-N

InChI=1S/C32H48O9/c1-17-29(35)24(37-5)14-27(39-17)41-21-8-10-30(3)20(13-21)6-7-23-22(30)9-11-31(4)28(19-12-26(34)38-16-19)25(40-18(2)33)15-32(23,31)36/h12,17,20-25,27-29,35-36H,6-11,13-16H2,1-5H3/t17-,20+,21-,22-,23+,24-,25-,27-,28-,29-,30-,31+,32-/m0/s1

[(3S,5R,8R,9S,10S,13R,14S,16S,17R)-14-hydroxy-3-[(2R,4S,5S,6S)-5-hydroxy-4-methoxy-6-methyloxan-2-yl]oxy-10,13-dimethyl-17-(5-oxo-2H-furan-3-yl)-1,2,3,4,5,6,7,8,9,11,12,15,16,17-tetradecahydrocyclopenta[a]phenanthren-16-yl] acetate

PBI-05204 PBI 05204 PBI05204

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 : ~100 mg/mL (~173.39 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (4.33 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

---

Solubility in Formulation 2: ≥ 2.5 mg/mL (4.33 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
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.

---

View More

Solubility in Formulation 3: ≥ 2.5 mg/mL (4.33 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

---

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