The anti-cancer efficacies of diffractaic, lobaric, and usnic acid:

Area of Science:

• Biochemistry
• Pharmacology
• Neuroscience

Background:

• Glioblastoma multiforme (GBM) is an aggressive primary brain tumor with high mortality despite standard treatments.
• Lichen secondary metabolites possess diverse bioactive functions, including demonstrated anti-cancer efficacy against various cancer types.
• Standard GBM therapies often result in significant side effects, necessitating the exploration of novel therapeutic agents.

Purpose of the Study:

• To investigate the effects of three lichen secondary metabolites—diffractaic acid (DA), lobaric acid (LA), and (+)-usnic acid (UA)—on glioblastoma multiforme (GBM) and primary rat cerebral cortex (PRCC) cells.
• To evaluate the impact of these metabolites on cell proliferation, oxidative status, and DNA damage.
• To determine the potential of these natural compounds as therapeutic agents for GBM.

Main Methods:

• Human U87MG glioblastoma cells and primary rat cerebral cortex (PRCC) cells were treated with varying concentrations of DA, LA, and UA.
• Cellular responses including lactate dehydrogenase release and 8-hydroxy-2'-deoxyguanosine levels were measured to assess toxicity and DNA damage.
• Inhibitory concentration 50% (IC50) values were calculated for each metabolite against both cell types.

Main Results:

• Lactate dehydrogenase and 8-hydroxy-2'-deoxyguanosine levels increased in a dose-dependent manner in both PRCC and U87MG cells upon exposure to the metabolites.
• Lobaric acid (LA) exhibited the lowest IC50 values (5.77 mg/L for U87MG, 9.08 mg/L for PRCC), indicating high toxicity.
• Diffractaic acid (DA) and (+)-usnic acid (UA) demonstrated significant antioxidant capacity in healthy PRCC cells at a concentration of 10 mg/L.

Conclusions:

• Lobaric acid (LA) displays potent cytotoxicity against both GBM and normal brain cells, highlighting its potential as a GBM therapeutic agent.
• Diffractaic acid (DA) and (+)-usnic acid (UA) possess antioxidant properties beneficial for healthy brain cells.
• Further research into lobaric acid (LA) is warranted for its potential role in future glioblastoma multiforme treatments.