Safflower has long been used to treat cerebrovascular diseases in China. We previously reported that kaempferol derivatives of safflower can bind DJ-1, a protein associated with Parkinson's disease (PD), and flavonoid extract of safflower exhibited neuroprotective effects in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of PD. In this study, a standardized safflower flavonoid extract (SAFE) was isolated from safflower and mainly contained flavonoids. Two marker compounds of SAFE, kaempferol 3-O-rutinoside and anhydrosafflor yellow B, were proven to suppress microtubule destabilization and decreased cell area, respectively. We confirmed that SAFE in dripping pill form could improve behavioural performances in a 6-hydroxydopamine (6-OHDA)-induced rat model of PD, partially via the suppression of α-synuclein overexpression or aggregation, as well as the suppression of reactive astrogliosis. Using an MRI tracer-based method, we found that 6-OHDA could change extracellular space (ECS) diffusion parameters, including a decrease in tortuosity and the rate constant of clearance and an increase in the elimination half-life of the tracer in the 6-OHDA-lesioned substantia nigra. SAFE treatment could partially inhibit the changes in ECS diffusion parameters, which might provide some information about neuronal loss and astrocyte activation. Consequently, our results indicate that SAFE is a potential therapeutic herbal product for treatment of PD.Parkinson's disease (PD) is the second most common disorder of the central nervous system (CNS), and its incidence is increasing among people over the age of 60 years 1 . PD is pathologically characterized by the loss of dopaminergic neurons in the substantia nigra (SN) and the formation of cytoplasmic inclusion bodies; however, the aetiology of PD remains elusive. The clinical features of PD include muscular rigidity, resting tremor, bradykinesia, and postural instability. By the time patients are diagnosed with PD, approximately 80% of the striatal dopamine terminals have been lost 2 , and destruction of terminal fields may precede cell body loss in the SN 3 . In rats, the unilateral intracerebral injection of 6-hydroxydopamine (6-OHDA) results in a selective degeneration of dopaminergic neurons, and this is a widely used animal model of PD. 6-OHDA induces a neurodegenerative process in the nigrostriatal system through the inhibition of mitochondrial complex function, which can lead to the induction of oxidative stress, inflammation 4-6 , abnormal protein aggregation 7,8 , elevated iron levels 9 and ultimately cell death. Dopamine replacement therapy remains the first line strategy in PD treatment. However, its effectiveness cannot modify the progression of the neurodegenerative process. Additionally, dopamine replacement therapy is associated with side-effects that include fluctuations in motor response and dyskinesia 10 . Increasing attention 1
Abstract:Parkinson's disease (PD) is a major age-related neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra par compacta (SNpc). Rotenone is a neurotoxin that is routinely used to model PD to aid in understanding the mechanisms of neuronal death. Safflower (Carthamus tinctorius. L.) has long been used to treat cerebrovascular diseases in China. This plant contains flavonoids, which have been reported to be effective in models of neurodegenerative disease. We previously reported that kaempferol derivatives from safflower could bind DJ-1, a protein associated with PD, and that a flavonoid extract from safflower exhibited neuroprotective effects in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of PD. In this study, a standardized safflower flavonoid extract (SAFE) was isolated from safflower and found to primarily contain flavonoids. The aim of the current study was to confirm the neuroprotective effects of SAFE in rotenone-induced Parkinson rats. The results showed that SAFE treatment increased body weight and improved rearing behavior and grip strength. SAFE (35 or 70 mg/kg/day) treatment reversed the decreased protein expression of tyrosine hydroxylase, dopamine transporter and DJ-1 and increased the levels of dopamine and its metabolite. In contrast, acetylcholine levels were decreased. SAFE treatment also led to partial inhibition of PD-associated changes in extracellular space diffusion parameters. These changes were detected using a magnetic resonance imaging (MRI) tracer-based method, which provides novel information regarding neuronal loss and astrocyte activation. Thus, our results indicate that SAFE represents a potential therapeutic herbal treatment for PD.
Macrophages play a critical role in a variety of inflammatory diseases. Activation of Keap1/Nrf2/HO-1 signaling results in inactivation of macrophages and amelioration of inflammatory and autoimmune conditions. Hence, discovery for the activators of Keap1/Nrf2/HO-1 signaling has become a promising strategy for treatment inflammatory diseases. In the current study, the anti-inflammatory potential of 7-deacetylgedunin (7-DGD), a limonin chemical isolated from the fruits of Toona sinensis (A. Juss.) Roem, was intensively examined in vivo and in vitro for the first time. Results showed that 7-DGD alleviated mice mortality induced by LPS. Mechanistic study showed that 7-DGD suppressed macrophage proliferation via induction of cell arrest at the G0/G1 phase. Furthermore, 7-DGD inhibited iNOS expression, which is correlated with the increases of NQO1, HO-1 and UGT1A1 mRNA expression as well as HO-1 protein expression level in the cells. More importantly, 7-DGD markedly decreased Keap1 expression, promoted p62 expression, and facilitated Nrf2 translocation and localization in the nucleus of macrophages, and in turn up-regulates these anti-oxidant enzymes expression, eventually mediated anti-inflammatory effect. Collectively, 7-DGD suppresses inflammation in vivo and in vitro, indicating that the compound is valuable for further investigation as an anti-inflammatory agent in future.
Safflower (Carthamus tinctorius. L.), a Chinese materia medica, is widely used for the treatment of cardiovascular and cerebrovascular diseases, with flavonoids being the major active components. Multiple flavonoids in safflower bind to Parkinson’s disease (PD)-related protein DJ-1. Safflower flavonoid extract (SAFE) improved behavioral indicators in a 6-hydroxydopamine (6-OHDA)-induced rat model of PD; however, the underlying mechanisms remain unclear. We used a 6-OHDA-induced mouse model of PD and a primary neuron-astrocyte coculture system to determine the neuroprotective effects and mechanisms of SAFE. After three weeks of SAFE administration, behavioral indicators of PD mice were improved. SAFE regulated the levels of tyrosine hydroxylase (TH) and dopamine metabolism. It significantly inhibited the activation of astrocytes surrounding the substantia nigra and reduced Iba-1 protein level in the striatum of PD mice. SAFE reduced the plasma content of inflammatory factors and suppressed the activation of nod-like receptor protein 3 (NLRP3) inflammasome. In the coculture system, kaempferol 3-O-rutinoside and anhydrosafflor yellow B significantly improved neuronal survival, suppressed neuronal apoptosis, and reduced IL-1β and IL-10 levels in the medium. Thus, SAFE showed a significant anti-PD effect, which is mainly associated with flavonoid anti-inflammatory activities.
BACKGROUND: miR-138 is one of the down-regulated miRNAs during acute spinal cord injury. Mixed lineage kinase 3 (MLK3), a key factor of jun N-terminal kinase (JNK)/mitogen-activated protein kinase (MAPK) pathway, is the target of miR-138. The aim of this study was to investigate the role of miR-138 in H 2 O 2 -treated BV-2 cells. METHODS: Murine microglia BV-2 cells were treated with H 2 O 2 and tested for cell viability and miR-138 expression. The cells were then transfected with miR-138 agomir or miR-138 antagomir, and treated with 200 μM H 2 O 2 for 24 h. The cellular apoptosis was detected by Aennexin V/PI staining. Expression of miR-138, MLK3, and other factors of JNK/MAPK pathway was detected. RESULTS: After treatment of various concentrations of H 2 O 2 , the cell viabilities were reduced, and miR-138 expression was down-regulated. Compared to the control cells, over-expressing miR-138 in BV-2 cells reduced apoptosis rate from 24.2 % to 11.9 %. Western blot further showed that JNK, p-JNK, c-jun, p-c-jun, p38 MAPK, and p-p38 MAPK were down-regulated. Expression of pro-apoptosis factors iNOS and COX-2 were also downregulated. Transfection of miR-138 antagomir produced the opposite effect of the transfection of miR-138 agomir. CONCLUSION: miR-138 was able to reduce H 2 O 2 -induced apoptosis in BV-2 cells. The protective effect was related to the down-regulation of MLK3 proteins and sequentially inhibiting JNK/MAPK signaling pathway (Fig. 3, Ref. 27). Text in PDF www.elis.sk. KEY WORDS: miR-138, mixed lineage kinase 3, apoptosis, microglia, jun N-terminal kinase.Neurocritical care unit, the second affi liated hospital,
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