Experiments found that luteolin-induced CH27 cell apoptosis was accompanied by activation of antioxidant enzymes, such as superoxide dismutase and catalase, but not through the production of reactive oxygen species and disruption of mitochondrial membrane potential. Therefore, the effects of luteolin on CH27 cell apoptosis were suspected to result from the antioxidant rather than the prooxidant action of luteolin.
Anti-Inflammatory - Luteolin displays specific anti-inflammatory effects at micromolar concentrations which are only partly explained by its anti-oxidant capacities. The anti-inflammatory activity includes activation of anti-oxidative enzymes, suppression of the NFκB pathway and inhibition of pro-inflammatory substances.
In vivo, luteolin reduced increased vascular permeability and was effective in animal models of inflammation after parenteral and oral application.
Some data for oral and topical bioavailability exist, but more quantitative research in this field is needed to evaluate the physiological and therapeutical potential of luteolin.
To better understand the immuno-modulatory effects of this important flavonoid, they performed a genome-wide expression analysis in pro-inflammatory challenged microglia treated with luteolin and conducted a phenotypic and functional characterization.
Findings confirm the inhibitory effects of luteolin on pro-inflammatory cytokine expression in microglia. Moreover, our transcriptomic data suggest that this flavonoid is a potent modulator of microglial activation and affects several signaling pathways leading to a unique phenotype with anti-inflammatory, anti-oxidative, and neuroprotective characteristics.
With the identification of several novel luteolin-regulated genes, our findings provide a molecular basis to understand the versatile effects of luteolin on microglial homeostasis. The data also suggest that luteolin could be a promising candidate to develop immuno-modulatory and neuroprotective therapies for the treatment of neurodegenerative disorders.
Anti-Depressant - In the present study, they sought to identify which constituent of CJ might be responsible for its antidepressant effects and determine probable mechanism of action. The ethanol extract of CJ was administered to mice then behavioral changes were evaluated in the forced-swimming test (FST) and open-field test (OFT).
Altogether, the present results suggest that the antidepressant-like effect of CJ was most probably induced by its constituent luteolin, mediated through potentiation of the GABAA receptor-Cl(-) ion channel complex.
The effect of luteolin on CA1 pyramidal layer thickness was also examined. The results demonstrated that luteolin significantly ameliorated the spatial learning and memory impairment induced by STZ treatment. STZ significantly reduced the thickness of CA1 pyramidal layer and treatment of luteolin completely abolished the inhibitory effect of STZ.
Results suggest that luteolin has a potentially protective effect on learning defects and hippocampal structures in AD.
Brain and Nerve Protection - The natural flavonoid luteolin has antioxidant, anti-inflammatory, mast cell–blocking, and neuroprotective effects. It was shown to improve cognitive performance in a mouse model of ASD, but its effect in humans has not been adequately studied.
The goal of this study was to assess the effectiveness and tolerability in white children with ASD of a dietary supplement containing 2 flavonoids (>95% pure), luteolin (100 mg/capsule, from chamomile) and quercetin (70 mg/capsule), and the quercetin glycoside rutin (30 mg/capsule) from the Sophora japonica leaf, formulated in olive kernel oil to increase oral absorption.
A total of 40 children completed the protocol. There was a significant improvement in adaptive functioning as measured by using the VABS age-equivalent scores (8.43 months in the communication domain, 7.17 months in daily living skills, and 8 months in the social domain; P < 0.005), as well as in overall behavior as indicated by the reduction (26.6%–34.8%) in Aberrant Behavior Checklist subscale scores.
These results are encouraging in that the combination of the flavonoids luteolin and quercetin seemed to be effective in reducing ASD symptoms, with no major adverse effects.
Anti-Cancer - In the present study, they investigated the chemo-sensitizing effect of luteolin in both cisplatin-resistant ovarian cancer cell line and a mice xenotransplant model. In vitro, CCK-8 assay showed that luteolin inhibited cell proliferation in a dose-dependent manner, and luteolin enhanced anti-proliferation effect of cisplatin on cisplatin-resistant ovarian cancer CAOV3/DDP cells.
They suggest that luteolin in combination with cisplatin could potentially be used as a new regimen for the treatment of ovarian cancer.