Asli Aykaç, Ahmet Özer Şehirli. Clin Psychopharmacol Neurosci 2020;18:174-87. https://doi.org/10.9758/cpn.2020.18.2.174

Methotrexate (MTX) is an effective cytotoxic agent which is used to treat malignancies and inflammatory diseases. Origanum onites (O. onites) is found throughout the Eastern Mediterranean region and has been used in traditional medicine. The essential oils (EOs) of O. onites rich in highly bioactive phytochemicals such as carvacrol (CVR) and has antiviral, antioxidant, anticancer and proapoptotic properties. The aim of this study was to investigate the protective effects of CVR and O. onites-EO treatment in MTX-induced hepatorenal toxic rats' liver and kidney tissues. The bcl-2/bax ratio, glutathione (GSH) level, malondialdehyde (MDA) level, and myeloperoxidase (MPO) activity of liver and kidney tissues were evaluated in the MTX-induced rat model. Results showed that the administration of CVR or O. onites-EO significantly increased bcl-2/bax expression and GSH levels as well as reduced MDA level and MPO activity in the kidney and liver tissues of MTX-induced rat model. In conclusion, our results suggest that O. onites-EO and CVR have protective effect in MTX-induced hepatorenal toxic rats' liver and kidney tissues by decreasing oxidative stress and apoptosis.

Despite many years of research, radical treatment of Alzheimer's disease (AD) has still not been found. Amyloid-β (Aβ) peptide is known to play an important role in the pathogenesis of this disease. AD is characterized by three main changes occurring in the central nervous system: (1) Aβ plaque accumulation that prevents synaptic communication, (2) the accumulation of hyperphosphorylated tau proteins that inhibit the transport of molecules inside neurons, and (3) neuronal cell loss of the limbic system. Mechanisms leading to Aβ accumulation in AD are excessive Aβ production as a result of mutations in amyloid precursor protein or genes, and impairment of clearance of Aβ due to changes in Aβ aggregation properties and/or Aβ removal processes. Human ATP-binding cassette (ABC) transporters are expressed in astrocyte, microglia, neuron, brain capillary endothelial cell, choroid plexus, choroid plexus epithelial cell, and ventricular ependymal cell. ABC transporters have essential detoxification and neuroprotective roles in the brain. The expression and functional changes in ABC transporters contribute to the accumulation of Aβ peptide. In conclusion, the review was aimed to summarize and highlight accumulated evidence in the literature focusing on the changing functions of human ABC transporter members, in AD pathogenesis and progression.