RESUMO
Ochratoxin A (OTA), a secondary fungal metabolite with nephrotoxicity, is widespread in numerous kinds of feeds and foodstuffs. Ursolic acid (UA), a water-insoluble pentacyclic triterpene acid, exists in a wide range of food materials and medicinal plants. Our earlier researches provided preliminary evidence that mitochondria- and mitochondria-associated endoplasmic reticulum membranes (MAMs)-located stress-responsive Lon protease 1 (Lonp1) had a protective function in OTA-induced nephrotoxicity, and the renoprotective function of UA against OTA partially due to Lonp1. However, whether other MAMs-located protiens, such as endoplasmic reticulum stress (ERS)-responsive Sigma 1-type opioid receptor (Sig-1R), contribute to the protection of UA against OTA-induced nephrotoxicity together with Lonp1 needs further investigation. In this study, the cell viability, reactive oxygen species, and protein expressions of human proximal tubule epithelial-originated kidney-2 (HK-2) cells varied with OTA and/or UA/CDDO-me/AVex-73/Sig-1R siRNA treatments were determined. Results indicated that a 24 h-treatment of 5 µM OTA could significantly induce mitochondrial-mediated apoptosis via repressing Lonp1 and Sig-1R, thereby enhancing the protein expressions of GRP78, p-PERK, p-eIF2α, CHOP, IRE1α, and Bax, and inhibiting the protein expression of Bcl-2 in HK-2 cells, which could be remarkably relieved by a 2 h-pre-treatment of 4 µM UA (P < 0.05). In conclusion, through mutual promotion between Lonp1 and Sig-1R, UA could effectively relieve OTA-induced apoptosis in vitro and break the vicious cycle between oxidative stress and ERS, which activated the mitochondrial apoptosis pathway.
Assuntos
Protease La , Humanos , Endorribonucleases , Proteínas Serina-Treonina Quinases , Mitocôndrias , Apoptose , Estresse do Retículo Endoplasmático , Proteínas Mitocondriais , Proteases Dependentes de ATP , Ácido UrsólicoRESUMO
A system was developed for home-based stroke motor rehabilitation of the ankle. A study was conducted to test the hypothesis that moving while concentrating will lead to greater recovery than movement alone. Sixteen post-stroke subjects participated, one half in a tracking training group and the other have in a move group. The tracking training group tracked a target waveform by moving their ankle to control the tracking cursor while the move group moved their ankle approximately the same amount but without target following. Over four weeks subjects completed 3600 trials. The results showed that the Tracking group had more improvement in ankle dorsiflexion compared to the Move group. The remaining assessment criteria showed no significant differences between the groups.