ABSTRACT
Background: The current work investigated the effect of melatonin on differentiation of adipose mesenchymal stem cells (AD-MSCs) into dopamine producing cells and its effect on autophagy process and alpha-Synuclein (α-Syn) secretion. Methods: AD-MSCs were characterized by flow cytometry and divided into 4 groups; i) control group (AD-MSCs without any treatment), ii) M+MSCs group (MSCs treated with 1 µM melatonin for 12 days), iii) DN group (MSCs cultured in neurobasal A medium and essential neuronal growth factors for 12 days) and iv) DN+M group (MSCs cultured in neurobasal A medium and 1µM melatonin for 12 days. By the end of experiments, the dopamine and α-Syn levels using ELISA, the expression of MAP-2, m-TOR and α-Syn genes at the level of mRNA and detection of autophagosomes formation using transmission electron microscope were performed. Results: We found that the isolated cells were MSCs due to their positivity expression for CD105 and CD90 and negativity expression for CD34 and CD45. The concentration of dopamine was significantly higher and α-Syn concentration was significantly lower in DN+M group when compared to other groups (P< 0.005). Also, this group showed the highly expression for MAP-2 gene and less expression for m-TOR and α-Syn genes (P< 0.005). Moreover, there was significantly increase in autophagosomes formation in this group than another group (P< 0.005). Conclusions: It is concluded that the melatonin promotes the differentiation of rat AD-MSCs into dopaminergic cells via induction of autophagy process and reduction of α-Syn secretion.
ABSTRACT
Background: To examine the impact of aging on the response of rats to pentylenetetrazole (PTZ)-induction of epilepsy and the possible role of oxidative stress and nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase (HO)-1 pathway in this response. Methods: Forty male albino rats were equally allocated into 4 groups; 1) Young control (YC) group, aged 8-12 weeks, 2) Old control (OC) group, aged 24 months, 3) PTZ-Young group: young rats received PTZ (50 mg/Kg, i.p. every other day) for 2 weeks and 4) PTZ-Old group: as group 3 but rats were old. The seizure score stage and latency to the first jerk were recorded in rats. Redox state markers in brain tissues including malondialdehyde (MDA), catalase and total antioxidant capacity (TAC) were evaluated. Also, the expression of Nrf2 and HO-1 genes were measured in the brain tissues. Results: Old rats showed an early and a significant rise in the seizure score with PTZ administration and a significant drop in the seizure latency compared to young rats (P <0.01). Also, old rats showed a significantly higher MDA concentration and a significantly lower TAC and catalase activity than young rats (P <0.01). Moreover, the expression of Nrf2 and HO-1 was significantly lowered in old rats compared to young rats with PTZ administration (P < 0.01). Conclusion: Aging increases the vulnerability of rats to PTZ-induced epilepsy. An effect might come down to the up-regulation of oxidative stress and the down regulation of antioxidant pathways including Nrf2 and HO-1.
