Interactions of Oleanolic Acid, Apigenin, Rutin, Resveratrol and Ferulic Acid with Phosphatidylcholine Lipid Membranes—A Spectroscopic and Machine Learning Study

Biologically active compounds present in the diet can interact with biological membranes (such as cell membranes), changing their properties. Their mutual interactions can influence their respective activities. In this study, we analyzed the interactions of oleanolic acid and phenolic compounds such as apigenin, rutin, resveratrol and ferulic acid with phosphatidylcholine membranes. Spectroscopic methods (fluorescence spectroscopy, dynamic light scattering) and machine learning were applied. The results of structural studies were compared with the antioxidant activity of the investigated substances in lipid membranes. In liposomes loaded with oleanolic acid, the pro-oxidant activity of resveratrol arises from changes in membrane structure, leading to an increased exposure of its hydrophilic region to external radicals. A similar mechanism may be involved in the pro-oxidant action of oleanolic acid. By contrast, apigenin, rutin and ferulic acid are present at the membrane surface. Their presence in this region protects the bilayer from radicals generated in the aqueous phase. Lower antioxidant activity observed in the case of ferulic aid is probably related to weaker interactions of this compound with the membrane, compared to the investigated flavonoids. Appropriate machine learning models for predicting oleanolic acid and phenolic compounds have been developed for the future application of intelligent predictive systems to optimizing manufacturing processes involving liposomes. The most effective regression model turned out to be the MLP 1:1-100-50-50-6:1, identifying resveratrol with a determination index of 0.83

Wpływ światła na syntezę alkaloidów w łubinie wąskolistnym (Lupinus angustifolius). I. Akumulacja alkaloidów [Influence of light on the alkaloids synthesis in Lupinus angustifolius. I. Alkaloids accumulation]

It was established that the time of irradiation as well as the intensity of light have a fundamental effect on the synthesis and accumulation of alkaloids in Lupinus angustifolius plants. The increase of time and intensity of irradiation caused the increase of the percentage of alkaloids in plants up to some maximum. A further increase of illumination caused the decrease of the percentage of alkaloids. This regularity also concerns the ester fraction of alkaloids in Lupinus angustifolius

Wpływ światła na syntezę alkaloidów w łubinie wąskolistnym (Lupinus angustifolius). I. Akumulacja alkaloidów [Influence of light on the alkaloids synthesis in Lupinus angustifolius. I. Alkaloids accumulation]

It was established that the time of irradiation as well as the intensity of light have a fundamental effect on the synthesis and accumulation of alkaloids in Lupinus angustifolius plants. The increase of time and intensity of irradiation caused the increase of the percentage of alkaloids in plants up to some maximum. A further increase of illumination caused the decrease of the percentage of alkaloids. This regularity also concerns the ester fraction of alkaloids in Lupinus angustifolius

Peripheral mitochondrial dysfunction in Alzheimer's disease: focus on lymphocytes

Alzheimer's disease (AD) is the most common progressive neurodegenerative disease. Today, AD affects millions of people worldwide and the number of AD cases will increase with increased life expectancy. The AD brain is marked by severe neurodegeneration like the loss of synapses and neurons, atrophy and depletion of neurotransmitter systems in the hippocampus and cerebral cortex. Recent findings suggest that these pathological changes are causally induced by mitochondrial dysfunction and increased oxidative stress. These changes are not only observed in the brain of AD patients but also in the periphery. In this review, we discuss the potential role of elevated apoptosis, increased oxidative stress and especially mitochondrial dysfunction as peripheral markers for the detection of AD in blood cells especially in lymphocytes. We discuss recent not otherwise published findings on the level of complex activities of the respiratory chain comprising mitochondrial respiration and the mitochondrial membrane potential (MMP). We obtained decreased basal MMP levels in lymphocytes from AD patients as well as enhanced sensitivity to different complex inhibitors of the respiratory chain. These changes are in line with mitochondrial defects obtained in AD cell and animal models, and in post-mortem AD tissue. Importantly, these mitochondrial alterations where not only found in AD patients but also in patients with mild cognitive impairment (MCI). These new findings point to a relevance of mitochondrial function as an early peripheral marker for the detection of AD and MCI