Chrysin is found in passion flower and honey. It is a flavonoid.
-To reach plasma levels that might more closely match the concentrations used in in vitro studies (typically micromolar), considerably high doses or advanced delivery mechanisms would be necessary.
Chrysin is widely summarized as modulating PI3K/Akt and MAPK pathways in cancer.
Chrysin — Chrysin is a naturally occurring flavone-class flavonoid found in honey, propolis, passionflower, and several plants. Its oncology relevance is mainly preclinical: it shows multi-pathway anticancer activity in cell and animal models, but native oral chrysin has very poor systemic bioavailability and no established approved oncology use.
Primary mechanisms (ranked):
- Suppression of PI3K/AKT survival signaling with downstream reduction in proliferation and survival programs.
- Induction of mitochondrial apoptosis through Bax/Bcl-2 shift, mitochondrial membrane potential loss, cytochrome c release, and caspase activation.
- Context-dependent ROS stress amplification in cancer cells, often linked to mitochondrial injury, ER stress, and apoptosis.
- ER stress / unfolded-protein-response activation leading to autophagy or stress-to-death coupling.
- Suppression of inflammatory, invasive, angiogenic, and metastatic signaling including NF-κB, MMPs, EMT, VEGF, and HIF-1α axes.
- Secondary antioxidant / NRF2-linked cytoprotection in some normal-cell or injury models, which is context-dependent and not necessarily anticancer-selective.
Bioavailability / PK relevance: Native oral chrysin has very poor systemic exposure because of low aqueous solubility, extensive intestinal/hepatic glucuronidation and sulfation, and efflux; human oral bioavailability has been reported as extremely low, often summarized as below 1%. Formulation strategies such as nanoparticles, lipid systems, micelles, cyclodextrins, or structural analogues are commonly proposed for systemic translation.
In-vitro vs systemic exposure relevance: Most anticancer studies use micromolar in-vitro concentrations that are unlikely to be reached in plasma after ordinary oral chrysin. Local intestinal exposure may be more plausible than systemic tumor exposure, but systemic anticancer claims should be treated as formulation-dependent.
LipoMicel may increase bioavailability
Clinical evidence status: Preclinical. Evidence is strong enough for mechanistic oncology interest in cell and animal models, including combination/sensitization studies, but there is no mature clinical oncology evidence establishing therapeutic benefit.
-Note half-life 2 hrs,
BioAv very poor often <1%
Pathways:
Graphical Pathways
- may induce
ROS production
- ROS↑ related:
MMP↓(ΔΨm),
ER Stress↑,
UPR↑,
GRP78↑,
Ca+2↑,
Cyt‑c↑,
Caspases↑,
DNA damage↑,
cl-PARP↑,
HSP↓
- May Lower AntiOxidant defense in Cancer Cells:
NRF2↓,
GSH↓
HO1↓
- May Raise
AntiOxidant
defense in Normal Cells:
ROS↓,
NRF2↑,
SOD↑,
GSH↑,
Catalase↑,
- lowers
Inflam">Inflammation :
NF-kB↓,
COX2↓,
Pro-Inflammatory Cytokines :
IL-1β↓,
TNF-α↓,
IL-6↓,
- inhibit Growth/Metastases :
TumMeta↓,
TumCG↓,
EMT↓,
MMP2↓,
MMP9↓,
TIMP2,
uPA↓,
VEGF↓,
ROCK1↓,
FAK↓,
RhoA↓,
NF-κB↓,
ERK↓
- reactivate genes thereby inhibiting cancer cell growth :
HDAC↓,
P53↑,
HSP↓,
- cause Cell cycle arrest :
TumCCA↑,
cyclin D1↓,
CDK2↓,
CDK4↓,
- inhibits Migration/Invasion :
TumCMig↓,
TumCI↓,
FAK↓,
ERK↓,
EMT↓,
TOP1↓,
TET1↓,
- inhibits
glycolysis
and
ATP depletion :
HIF-1α↓,
cMyc↓,
GLUT1↓,
LDH↓,
HK2↓,
PDKs↓,
HK2↓,
GRP78↑,
GlucoseCon↓
- inhibits
angiogenesis↓ :
VEGF↓,
HIF-1α↓,
Notch↓,
PDGF↓,
EGFR↓,
- Others: PI3K↓,
AKT↓,
STAT↓,
Wnt↓,
AMPK↓,
ERK↓,
JNK,
TrxR,
- Synergies:
chemo-sensitization,
chemoProtective,
RadioSensitizer,
Others(review target notes),
Neuroprotective,
Cognitive,
Renoprotection,
Hepatoprotective,
CardioProtective,
- Selectivity:
Cancer Cells vs Normal Cells
Chrysin Mechanistic Profile
| Rank |
Pathway / Axis |
Cancer Cells |
Normal Cells |
TSF |
Primary Effect |
Notes / Interpretation |
| 1 |
PI3K AKT survival signaling |
PI3K↓; AKT phosphorylation↓; survival signaling↓ |
↔ |
R, G |
Growth and survival suppression |
Central hub mechanism reported across multiple tumor models; also supports chemosensitization. |
| 2 |
Mitochondrial apoptosis |
MMP↓; Bax↑; Bcl-2↓; cytochrome c↑; caspase-9/3↑ |
↔ or lower sensitivity |
R, G |
Intrinsic apoptosis execution |
One of the most consistent anticancer endpoints, usually downstream of stress and survival-pathway suppression. |
| 3 |
Mitochondrial ROS stress |
ROS↑ (context-dependent); oxidative stress↑; lipid peroxidation↑ |
ROS↓ or antioxidant protection (context-dependent) |
P, R, G |
Stress amplification |
Direction is dose- and model-dependent; cancer models often show pro-oxidant stress, while normal injury models may show antioxidant behavior. |
| 4 |
ER stress and UPR |
ER stress↑; GRP78↑; UPR↑; autophagy or apoptosis↑ |
↔ |
R, G |
Stress-to-death coupling |
Important in several chrysin cancer models and in some drug-combination effects. |
| 5 |
NF-κB inflammatory transcription |
NF-κB↓; COX-2↓; IL-6↓; TNF-α↓ |
Inflammatory injury signaling↓ |
R, G |
Anti-inflammatory and anti-survival signaling |
May contribute to reduced proliferation, invasion, and cytokine-driven tumor support. |
| 6 |
Invasion EMT and MMPs |
EMT↓; MMP-2↓; MMP-9↓; uPA↓; migration↓; invasion↓ |
↔ |
G |
Anti-invasive phenotype |
Mechanistically relevant for metastasis models but generally later and context-dependent. |
| 7 |
Angiogenesis and HIF-1α VEGF signaling |
HIF-1α↓; VEGF↓; angiogenic output↓ |
↔ |
G |
Anti-angiogenic support |
Reported in preclinical models; may overlap with oxidative stress and DNA damage response pathways. |
| 8 |
Glycolysis and metabolic stress |
GLUT1↓; HK2↓; LDH↓; PDK1↓; lactate production↓; ATP↓ |
↔ |
G |
Metabolic suppression |
Relevant but less central than apoptosis and survival signaling; strongest interpretation is model-dependent. |
| 9 |
NRF2 antioxidant axis |
NRF2↓ or antioxidant defense↓ (model-dependent) |
NRF2↑; SOD↑; GSH↑; catalase↑ (context-dependent) |
R, G |
Context-dependent redox selectivity |
Potentially useful but also interpret carefully because NRF2 activation can be protective in normal cells and sometimes undesirable in cancer cells. |
| 10 |
Chemosensitization and radiosensitization |
Drug-induced toxicity↑; apoptosis↑; resistance signaling↓ |
Chemoprotection reported in some injury models |
G |
Adjunct sensitization |
Promising preclinical adjunct signal, but not clinically established. |
| 11 |
Clinical Translation Constraint |
Systemic exposure low after native oral dosing |
Dose and formulation constraints |
G |
Translation limitation |
Very poor oral bioavailability is the dominant practical constraint; formulation or local GI targeting is likely required. |
Time-Scale Flag (TSF): P / R / G
- P: 0–30 min (primary/physical–chemical effects; rapid signaling / phosphorylation shifts)
- R: 30 min–3 hr (acute stress-response and redox signaling)
- G: >3 hr (gene-regulatory adaptation and phenotype-level outcomes)
|