Bullatacin / ROS Cancer Research Results

BUL, Bullatacin: Click to Expand ⟱
Features:

Bullatacin - Annonaceous Acetogenin

Type: Annonaceous acetogenin / bioactive natural compound

Sources: Bullatacin occurs in plants of the Annonaceae family and has been isolated from Annona atemoya.

Function: Bullatacin is a highly cytotoxic annonaceous acetogenin that interferes with cellular energy metabolism and mitochondrial electron transport. It has also been reported to inhibit NADH oxidase activity and alter intracellular signaling associated with tumor-cell survival.

Cancer: Preclinical studies demonstrate potent antiproliferative and pro-apoptotic activity. Bullatacin inhibits hepatoma-cell proliferation, induces apoptosis, and has shown antitumor activity in experimental tumor models. Reported mechanisms include inhibition of mitochondrial energy metabolism, NADH oxidase activity, and reductions in intracellular cAMP and cGMP signaling. Clinical anticancer efficacy has not been established.

Bullatacin — a highly lipophilic Annonaceous acetogenin and potent mitochondrial poison isolated from plants of the Annonaceae family, including Annona atemoya and Annona bullata. It is formally classified as a natural-product acetogenin and experimental cytotoxic/antitumor agent. Bullatacin is best characterized as a mitochondrial complex I inhibitor that suppresses oxidative phosphorylation and cellular ATP production. It has unusually high cytotoxic potency in several cancer-cell models, including multidrug-resistant cells, but has no established therapeutic use in humans. Its mechanism overlaps substantially with that of other neurotoxic Annonaceous acetogenins.

Primary mechanisms (ranked):

  1. Mitochondrial respiratory-chain complex I inhibition, causing impaired NADH oxidation, oxidative phosphorylation suppression, and ATP depletion.
  2. Mitochondrial ROS generation and loss of mitochondrial membrane potential, activating cytochrome-c release, caspase-9, caspase-3, PARP cleavage, and intrinsic apoptosis.
  3. Endoplasmic-reticulum stress activation and immunogenic cell death, including surface calreticulin/HSP90 exposure and later release of HMGB1, HSP70, and HSP90.
  4. Reduction of intracellular cAMP and cGMP signaling, associated with increased apoptosis in hepatoma cells.
  5. Inhibition of plasma-membrane NADH oxidase activity in susceptible tumor cells.
  6. Preferential vulnerability of some multidrug-resistant cancer cells through severe ATP depletion, potentially compromising ATP-dependent resistance mechanisms.

Bioavailability / PK relevance: Human pharmacokinetics have not been established. Bullatacin is highly lipophilic, but there is insufficient validated systemic PK information to define clinically achievable plasma or tumor concentrations. Effective experimental concentrations can be in the low-nanomolar range, and antitumor activity has been demonstrated in some mouse models after parenteral dosing. However, efficacy and toxicity appear to have a narrow and model-dependent relationship. There is no established oral dose, therapeutic window, formulation, or human exposure target.

In-vitro vs systemic exposure relevance: Bullatacin frequently produces cellular effects at nanomolar concentrations, including approximately 10 nM in colon-cancer immunogenic-cell-death studies and an approximately 7.8 nM one-day ED50 in hepatoma cells. These concentrations cannot presently be compared reliably with achievable human systemic exposure because human PK data are lacking. The mitochondrial complex-I mechanism is concentration-driven and is not cancer-specific; systemic exposure therefore raises substantial normal-tissue and neurological safety concerns.

Clinical evidence status: Preclinical only. Evidence consists predominantly of biochemical studies, cancer-cell experiments, and animal tumor models. Some murine models have demonstrated tumor-growth inhibition, while at least one ovarian tumor model found no survival benefit within nonlethal dosing ranges. No established human anticancer trials, approved indication, or regulatory therapeutic use for bullatacin was identified. The Annonaceous acetogenin class has an important neurotoxicity signal, including experimental mitochondrial complex-I-mediated neurodegeneration and epidemiologic associations between chronic Annonaceae exposure and atypical parkinsonism.

Bullatacin Mechanistic Profile

Rank Pathway / Axis Cancer Cells Normal Cells TSF Primary Effect Notes / Interpretation
1 Mitochondrial Complex I and Oxidative Phosphorylation Complex I ↓
NADH oxidation ↓
ATP ↓
Complex I ↓ (exposure-dependent)
ATP ↓
P/R Energetic collapse and growth inhibition Core mechanism of Annonaceous acetogenins. Bullatacin inhibits mitochondrial electron transport at complex I. This mechanism is not inherently cancer-specific.
2 Mitochondrial ROS and Intrinsic Apoptosis ROS
Mitochondrial membrane potential ↓
Cytochrome c ↑
Caspase-9 ↑
Caspase-3 ↑
PARP cleavage ↑
Apoptosis ↑
Potential ROS ↑ and mitochondrial injury ↑ (context-dependent) R/G Mitochondria-dependent apoptotic cell death ROS generation is mechanistically important in ABCB1-overexpressing KBv200 cells. N-acetylcysteine reduces both ROS generation and apoptosis. Caspase-9 rather than caspase-8 is dominant in this model.
3 Endoplasmic Reticulum Stress and Immunogenic Cell Death ER stress ↑
Calreticulin surface exposure ↑
HSP90 surface exposure ↑
HMGB1 release ↑
HSP70 release ↑
Macrophage phagocytosis ↑
Not established R/G Immunogenic tumor-cell death Demonstrated in SW480 and HT-29 colon cancer cells at approximately 10 nM. Early ICD markers emerge within hours, whereas extracellular DAMP release develops later.
4 cAMP and cGMP Signaling cAMP ↓
cGMP ↓
Apoptosis ↑
Not established P/R/G Suppression of cyclic-nucleotide survival signaling Reductions begin rapidly and become pronounced over several hours. Pharmacologic elevation of cAMP or cGMP partially antagonized bullatacin-induced apoptosis in hepatoma cells.
5 Plasma Membrane NADH Oxidase NADH oxidase ↓ ↔ in rat liver plasma-membrane preparations P/R Suppression of tumor-cell plasma-membrane redox activity Inhibition was reported in HeLa and HL-60 plasma membranes but not rat liver plasma membranes. This showed greater tumor selectivity than mitochondrial respiratory inhibition in the experimental system.
6 Multidrug Resistance and ATP Dependence ATP ↓↓
ABCB1-overexpressing cell survival ↓
Apoptosis ↑
Not established R/G Preferential killing of some multidrug-resistant cells Some P-glycoprotein-positive and multidrug-resistant tumor cells are unusually sensitive. Evidence supports ATP depletion rather than direct ABCB1 inhibition as the major explanation.
7 Cell Proliferation DNA synthesis ↓
Proliferation ↓
Viability ↓
Potential proliferation and viability ↓ (dose-dependent) G Potent cytostatic and cytotoxic activity Low-nanomolar activity has been reported in several tumor models, although potency varies markedly among cell types and experimental systems.
8 Clinical Translation Constraint Therapeutic exposure not established Mitochondrial toxicity ↑
Potential neurotoxicity ↑
G Limits systemic therapeutic development No human PK, validated therapeutic window, clinical efficacy, or approved formulation. Class-related complex-I inhibition raises concern for neuronal ATP depletion and neurodegeneration. Animal efficacy has also been inconsistent across tumor models.

P: 0–30 min    R: 30 min–3 hr    G: >3 hr



ROS, Reactive Oxygen Species: Click to Expand ⟱
Source: HalifaxProj (inhibit)
Type:
Reactive oxygen species (ROS) are highly reactive molecules that contain oxygen and can lead to oxidative stress in cells. They play a dual role in cancer biology, acting as both promoters and suppressors of cancer.
ROS can cause oxidative damage to DNA, leading to mutations that may contribute to cancer initiation and progression. So normally you want to inhibit ROS to prevent cell mutations.
However excessive ROS can induce apoptosis (programmed cell death) in cancer cells, potentially limiting tumor growth. Chemotherapy typically raises ROS.
-mitochondria is the main source of reactive oxygen species (ROS) (and the ETC is heavily related)
ROS Homeostasis in Cancer Cells and Its Potential as a Therapeutic Target

"Reactive oxygen species (ROS) are two electron reduction products of oxygen, including superoxide anion, hydrogen peroxide, hydroxyl radical, lipid peroxides, protein peroxides and peroxides formed in nucleic acids 1. They are maintained in a dynamic balance by a series of reduction-oxidation (redox) reactions in biological systems and act as signaling molecules to drive cellular regulatory pathways."
"During different stages of cancer formation, abnormal ROS levels play paradoxical roles in cell growth and death 8. A physiological concentration of ROS that maintained in equilibrium is necessary for normal cell survival. Ectopic ROS accumulation promotes cell proliferation and consequently induces malignant transformation of normal cells by initiating pathological conversion of physiological signaling networks. Excessive ROS levels lead to cell death by damaging cellular components, including proteins, lipid bilayers, and chromosomes. Therefore, both scavenging abnormally elevated ROS to prevent early neoplasia and facilitating ROS production to specifically kill cancer cells are promising anticancer therapeutic strategies, in spite of their contradictoriness and complexity."
"ROS are the collection of derivatives of molecular oxygen that occur in biology, which can be categorized into two types, free radicals and non-radical species. The non-radical species are hydrogen peroxide (H 2O 2 ), organic hydroperoxides (ROOH), singlet molecular oxygen ( 1 O 2 ), electronically excited carbonyl, ozone (O3 ), hypochlorous acid (HOCl, and hypobromous acid HOBr). Free radical species are super-oxide anion radical (O 2•−), hydroxyl radical (•OH), peroxyl radical (ROO•) and alkoxyl radical (RO•) [130]. Any imbalance of ROS can lead to adverse effects. H2 O 2 and O 2 •− are the main redox signalling agents. The cellular concentration of H2 O 2 is about 10−8 M, which is almost a thousand times more than that of O2 •−".
"Radicals are molecules with an odd number of electrons in the outer shell [393,394]. A pair of radicals can be formed by breaking a chemical bond or electron transfer between two molecules."

Recent investigations have documented that polyphenols with good antioxidant activity may exhibit pro-oxidant activity in the presence of copper ions, which can induce apoptosis in various cancer cell lines but not in normal cells. "We have shown that such cell growth inhibition by polyphenols in cancer cells is reversed by copper-specific sequestering agent neocuproine to a significant extent whereas iron and zinc chelators are relatively ineffective, thus confirming the role of endogenous copper in the cytotoxic action of polyphenols against cancer cells. Therefore, this mechanism of mobilization of endogenous copper." > Ions could be one of the important mechanisms for the cytotoxic action of plant polyphenols against cancer cells and is possibly a common mechanism for all plant polyphenols. In fact, similar results obtained with four different polyphenolic compounds in this study, namely apigenin, luteolin, EGCG, and resveratrol, strengthen this idea.
Interestingly, the normal breast epithelial MCF10A cells have earlier been shown to possess no detectable copper as opposed to breast cancer cells [24], which may explain their resistance to polyphenols apigenin- and luteolin-induced growth inhibition as observed here (Fig. 1). We have earlier proposed [25] that this preferential cytotoxicity of plant polyphenols toward cancer cells is explained by the observation made several years earlier, which showed that copper levels in cancer cells are significantly elevated in various malignancies. Thus, because of higher intracellular copper levels in cancer cells, it may be predicted that the cytotoxic concentrations of polyphenols required would be lower in these cells as compared to normal cells."

Majority of ROS are produced as a by-product of oxidative phosphorylation, high levels of ROS are detected in almost all cancers.
-It is well established that during ER stress, cytosolic calcium released from the ER is taken up by the mitochondrion to stimulate ROS overgeneration and the release of cytochrome c, both of which lead to apoptosis.

Note: Products that may raise ROS can be found using this database, by:
Filtering on the target of ROS, and selecting the Effect Direction of ↑

Targets to raise ROS (to kill cancer cells):
• NADPH oxidases (NOX): NOX enzymes are involved in the production of ROS.
    -Targeting NOX enzymes can increase ROS levels and induce cancer cell death.
    -eNOX2 inhibition leads to a high NADH/NAD⁺ ratio which can lead to increased ROS
• Mitochondrial complex I: Inhibiting can increase ROS production
• P53: Activating p53 can increase ROS levels(by inducing the expression of pro-oxidant genes)
Nrf2 inhibition: regulates the expression of antioxidant genes. Inhibiting Nrf2 can increase ROS levels
• Glutathione (GSH): an antioxidant. Depleting GSH can increase ROS levels
• Catalase: Catalase converts H2O2 into H2O+O. Inhibiting catalase can increase ROS levels
• SOD1: converts superoxide into hydrogen peroxide. Inhibiting SOD1 can increase ROS levels
• PI3K/AKT pathway: regulates cell survival and metabolism. Inhibiting can increase ROS levels
HIF-1α inhibition: regulates genes involved in metabolism and angiogenesis. Inhibiting HIF-1α can increase ROS
• Glycolysis: Inhibiting glycolysis can increase ROS levels • Fatty acid oxidation: Cancer cells often rely on fatty acid oxidation for energy production.
-Inhibiting fatty acid oxidation can increase ROS levels
• ER stress: Endoplasmic reticulum (ER) stress can increase ROS levels
• Autophagy: process by which cells recycle damaged organelles and proteins.
-Inhibiting autophagy can increase ROS levels and induce cancer cell death.
• KEAP1/Nrf2 pathway: regulates the expression of antioxidant genes.
    -Inhibiting KEAP1 or activating Nrf2 can increase ROS levels and induce cancer cell death.
• DJ-1: regulates the expression of antioxidant genes. Inhibiting DJ-1 can increase ROS levels
• PARK2: regulates the expression of antioxidant genes. Inhibiting PARK2 can increase ROS levels
SIRT1 inhibition:regulates the expression of antioxidant genes. Inhibiting SIRT1 can increase ROS levels
AMPK activation: regulates energy metabolism and can increase ROS levels when activated.
mTOR inhibition: regulates cell growth and metabolism. Inhibiting mTOR can increase ROS levels
HSP90 inhibition: regulates protein folding and can increase ROS levels when inhibited.
• Proteasome: degrades damaged proteins. Inhibiting the proteasome can increase ROS levels
Lipid peroxidation: a process by which lipids are oxidized, leading to the production of ROS.
    -Increasing lipid peroxidation can increase ROS levels
• Ferroptosis: form of cell death that is regulated by iron and lipid peroxidation.
    -Increasing ferroptosis can increase ROS levels
• Mitochondrial permeability transition pore (mPTP): regulates mitochondrial permeability.
    -Opening the mPTP can increase ROS levels
• BCL-2 family proteins: regulate apoptosis and can increase ROS levels when inhibited.
• Caspase-independent cell death: a form of cell death that is regulated by ROS.
    -Increasing caspase-independent cell death can increase ROS levels
• DNA damage response: regulates the repair of DNA damage. Increasing DNA damage can increase ROS
• Epigenetic regulation: process by which gene expression is regulated.
    -Increasing epigenetic regulation can increase ROS levels

-PKM2, but not PKM1, can be inhibited by direct oxidation of cysteine 358 as an adaptive response to increased intracellular reactive oxygen species (ROS)

ProOxidant Strategy:(inhibit the Mevalonate Pathway (likely will also inhibit GPx)
-HydroxyCitrate (HCA) found as supplement online and typically used in a dose of about 1.5g/day or more
-Atorvastatin typically 40-80mg/day, -Dipyridamole typically 200mg 2x/day Combined effect research
-Lycopene typically 100mg/day range (note debatable as it mainly lowers NRF2)

Dual Role of Reactive Oxygen Species and their Application in Cancer Therapy
ROS-Inducing Interventions in Cancer — Canonical + Mechanistic Reference
-generated from AI and Cancer database
ROS rating:  +++ strong | ++ moderate | + weak | ± mixed | 0 none
NRF2:        ↓ suppressed | ↑ activated | ± mixed | 0 none
Conditions:  [D] dose  [Fe] metal  [M] metabolic  [O₂] oxygen
             [L] light [F] formulation [T] tumor-type [C] combination

Item ROS NRF2 Condition Mechanism Class Remarks
ROS">Piperlongumine +++ [D][T] ROS-dominant
ROS">Shikonin +++↓/±[D][T]ROS-dominant
ROS">Vitamin K3 (menadione) +++[D]ROS-dominant
ROS">Copper (ionic / nano) +++[Fe][F]ROS-dominant
ROS">Sodium Selenite +++[D]ROS-dominant
ROS">Juglone +++[D]ROS-dominant
ROS">Auranofin +++[D]ROS-dominant
ROS">Photodynamic Therapy (PDT) +++0[L][O₂]ROS-dominant
ROS">Radiotherapy / Radiation +++0[O₂]ROS-dominant
ROS">Doxorubicin +++[D]ROS-dominant
ROS">Cisplatin ++[D][T]ROS-dominant
ROS">Salinomycin ++[D][T]ROS-dominant
ROS">Artemisinin / DHA ++[Fe][T]ROS-dominant
ROS">Sulfasalazine ++[C][T]ROS-dominant
ROS">FMD / fasting ++[M][C][O₂]ROS-dominant
ROS">Vitamin C (pharmacologic) ++[Fe][D]ROS-dominant
ROS">Silver nanoparticles ++±[F][D]ROS-dominant
ROS">Gambogic acid ++[D][T]ROS-dominant
ROS">Parthenolide ++[D][T]ROS-dominant
ROS">Plumbagin ++[D]ROS-dominant
ROS">Allicin ++[D]ROS-dominant
ROS">Ashwagandha (Withaferin A) ++[D][T]ROS-dominant
ROS">Berberine ++[D][M]ROS-dominant
ROS">PEITC ++[D][C]ROS-dominant
ROS">Methionine restriction +[M][C][T]ROS-secondary
ROS">DCA +±[M][T]ROS-secondary
ROS">Capsaicin +±[D][T]ROS-secondary
ROS">Galloflavin +0[D]ROS-secondary
ROS">Piperine +±[D][F]ROS-secondary
ROS">Propyl gallate +[D]ROS-secondary
ROS">Scoulerine +?[D][T]ROS-secondary
ROS">Thymoquinone ±±[D][T]Dual redox
ROS">Emodin ±±[D][T]Dual redox
ROS">Alpha-lipoic acid (ALA) ±[D][M]NRF2-dominant
ROS">Curcumin ±↑/↓[D][F]NRF2-dominant
ROS">EGCG ±↑/↓[D][O₂]NRF2-dominant
ROS">Quercetin ±↑/↓[D][Fe]NRF2-dominant
ROS">Resveratrol ±[D][M]NRF2-dominant
ROS">Sulforaphane ±↑↑[D]NRF2-dominant
ROS">Lycopene 0Antioxidant
ROS">Rosmarinic acid 0Antioxidant
ROS">Citrate 00Neutral


Scientific Papers found: Click to Expand⟱
7969- BUL,    Bullatacin triggered ABCB1-overexpressing cell apoptosis via the mitochondrial-dependent pathway
- NA, Cerv, KBv200
ROS↑, MMP↓, cl‑Casp3↑, cl‑Casp9↓, cl‑PARP↑, Cyt‑c↑, eff↓,
7976- BUL,    Antitumor activity and toxicity relationship of annonaceous acetogenins
- in-vitro, HCC, H22
toxicity↓, TumCG↓, *toxicity↑, *ROS↑, *Ca+2↑, *BAX↑,

Showing Research Papers: 1 to 2 of 2

* indicates research on normal cells as opposed to diseased cells
Total Research Paper Matches: 2

Pathway results for Effect on Cancer / Diseased Cells:


Redox & Oxidative Stress(tgid=1)

ROS↑, 1,  

Mitochondria & Bioenergetics(tgid=3)

MMP↓, 1,  

Cell Death(tgid=5)

cl‑Casp3↑, 1,   cl‑Casp9↓, 1,   Cyt‑c↑, 1,  

DNA Damage & Repair(tgid=10)

cl‑PARP↑, 1,  

Proliferation, Differentiation & Cell State(tgid=12)

TumCG↓, 1,  

Drug Metabolism & Resistance(tgid=21)

eff↓, 1,  

Functional Outcomes(tgid=23)

toxicity↓, 1,  
Total Targets: 9

Pathway results for Effect on Normal Cells:


Redox & Oxidative Stress(tgid=1)

ROS↑, 1,  

Cell Death(tgid=5)

BAX↑, 1,  

Migration(tgid=13)

Ca+2↑, 1,  

Functional Outcomes(tgid=23)

toxicity↑, 1,  
Total Targets: 4

Scientific Paper Hit Count for: ROS, Reactive Oxygen Species
Query results interpretion may depend on "conditions" listed in the research papers.
Such Conditions may include : 
  -low or high Dose
  -format for product, such as nano of lipid formations
  -different cell line effects
  -synergies with other products 
  -if effect was for normal or cancerous cells
Filter Conditions: Pro/AntiFlg:%  IllCat:%  CanType:%  Cells:%  prod#:468  Target#:275  State#:%  Dir#:%
wNotes=0 sortOrder:rid,rpid

 

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