Protective effect of N-acetyl cysteine on the mitochondrial dynamic imbalance in temporal lobe epilepsy: Possible role of mTOR.

Understanding the underlying molecular mechanisms involved in epilepsy is critical for the development of more effective therapies. It is believed that mTOR (Mechanistic Target of Rapamycin kinases) activity and the mitochondrial dynamic balance change during epilepsy. mTOR affects mitochondrial fission by stimulating the translation of mitochondrial fission process 1 (MTFP1). In This study, the protective role of N-acetylcysteine was studied in temporal lobe epilepsy (TLE) through the regulation of mTOR and mitochondrial dynamic proteins. Rats received N-acetylcysteine (oral administration) seven days before induction of epilepsy, followed by one day after epilepsy. TLE was induced by microinjection of kainite into the left lateral ventricle. The total mTOR and Drp1 levels in the hippocampus were evaluated by western blotting. MFN1 was assessed using immunohistochemistry, and the expression of Fis.1 and MTFP1 (fission-related proteins) and OPA (fusion-related protein) were detected by real-time PCR. The mitochondrial membrane potential was measured by Rhodamin 123. The results showed that 72 h after induction of epilepsy, the mTOR protein level increased, and the balance of the mitochondrial dynamic was disturbed; however, oral administration of NAC decreased the mTOR protein level and improved the mitochondrial dynamic. These findings indicate that NAC plays a neuroprotective role in temporal lobe epilepsy, probably through decreasing the mTOR protein level, which can improve the imbalance in the mitochondrial dynamic.

Mitochondrial ATP-sensitive potassium channel, MitoKATP, ameliorates mitochondrial dynamic disturbance induced by temporal lobe epilepsy.

Temporal lobe epilepsy leads to a disturbance in the function and dynamic of the mitochondria. The mitoKATP channel is an important factor in controlling mitochondrial function. In this study, the protective role of mitoKATP was studied in temporal lobe epilepsy through the regulation of mitochondrial dynamic proteins. After induction of epilepsy, 5-HD (the inhibitor of mitoKATP) was administered daily for either 24 or 72 h. The results revealed an imbalance in dynamic proteins after epilepsy, specifically in the first 72 h. The disturbance in the mitochondrial dynamic worsened after blocking mitoKATP. In conclusion, mitoKATP has an important role in balancing mitochondrial dynamic proteins in epilepsy.

The possible role of progranulin on anti-inflammatory effects of metformin in temporal lobe epilepsy.

Temporal lobe epilepsy (TLE) is the most prevalent and drug-resistant form of parietal epilepsy. TLE is accompanied by neuroinflammation in the brain, which involves reactive glial cells. Metformin is an old antidiabetic drug with anti-inflammatory and neuroprotective effects. Considering the importance of inflammation in epilepsy, we have investigated the effect of metformin on astrogliosis markers as well as pro and anti-inflammatory cytokines and its effect on progranulin expression (an important neuroprotective protein in epilepsy) in a rat TLE model. TLE was induced by intracerebroventricular microinjection of kainic acid. Metformin was orally administered for two weeks before the induction of epilepsy. Astrogliosis markers (GFAP and S100B), as well as IL-1ß and IL- 10 levels, were detected by ELISA. The progranulin level was measured by Western blotting and immunohistochemistry in the hippocampus. Our results showed basal levels of GFAP, S100B, and pro-inflammatory cytokine increased in the epileptic rats but were significantly ameliorated after pretreatment with metformin. However, anti-inflammatory cytokine and progranulin also increased in the pre-treated rats and metformin alone group. An increment in the progranulin level emphasizes the importance of this protein in epilepsy. Hence, metformin may exert at least some of its anti-inflammatory effects by increasing progranulin level. In sum, we have concluded that progranulin can be a key mediator in epilepsy, and the anti-inflammatory action of metformin in status epilepticus is through increasing the secretion of IL-10 and inhibiting IL-1 ß and astrogliosis.

Protective effect of diosgenin on LPS/D-Gal-induced acute liver failure in C57BL/6 mice.

Acute liver failure (ALF) is a deadly clinical syndrome, which leads to a rapid loss of normal liver function. Diosgenin is a natural steroidal sapogenin found in various plant families. Various studies have shown that diosgenin have therapeutic or preventive effect in various diseases such as cancer, cardiovascular disorders, type 2 diabetes, and neurodegenerative disorders. In this study, we evaluated effects of diosgenin on mice model of ALF. Animal model of ALF was induced by intraperitoneal injection of lipopolysaccharide (LPS)/d-galactosamine (D-Gal). The male C57BL/6 mice were randomly divided into 3 groups: control group, LPS/D-Gal group, and LPS/D-Gal + diosgenin group (50 mg/kg). Mice in the LPS/D-Gal group received a combination of LPS (50 µg/kg) and D-Gal (400 mg/kg) intraperitoneally. LPS/D-Gal + diosgenin group received diosgenin twice orally 24 h and 1 h before receiving LPS/D-Gal. Markers of liver injury including ALT, AST and ALP were measured in blood samples in addition to determination of oxidative stress and inflammatory markers including MDA, nitrite, ROS, catalase, SOD, Nrf2, IL-1ß, IL-6, TLR4, TNF-α and NF-κB in hepatic tissue. Administration of diosgenin could greatly reduce serum levels of ALT, AST, and ALP. Besides, hepatic levels of MDA, ROS, IL-1ß, IL-6, TLR4, TNF-α, and NF-κB significantly decreased and SOD activity and Nrf2 level increased in comparison with the LPS/D-Gal group. In addition, myeloperoxidase activity as a marker of neutrophil infiltration decreased following diosgenin administration. In summary, diosgenin led to reduction of liver injury indices and oxidative stress and inflammatory events and diosgenin has probably hepatoprotecive effects in ALF.