Protective effect of extract of the Camellia japonica L. on cerebral ischemia-reperfusion injury in rats

Favorable Effects of Astaxanthin on Brain Damage due to Ischemia- Reperfusion Injury

BACKGROUND

Activated inflammation and oxidant stress during cerebral ischemia reperfusion injury (IRI) lead to brain damage. Astaxanthin (ASX) is a type of carotenoid with a strong antioxidant effect.

OBJECTIVE

The aim of this study was to investigate the role of ASX on brain IRI.

METHODS

A total of 42 adult male Sprague-Dawley rats were divided into 3 groups as control (n=14) group, IRI (n=14) group and IRI + ASX (n=14) group. Cerebral ischemia was instituted by occluding middle cerebral artery for 120 minutes and subsequently, reperfusion was performed for 48 hours. Oxidant parameter levels and protein degradation products were evaluated. Hippocampal and cortex cell apoptosis, neuronal cell count, neurological deficit score were evaluated.

RESULTS

In the IRI group, oxidant parameter levels and protein degradation products in the tissue were increased compared to control group. However, these values were significantly decreased in the IRI + ASX group (p<0.05). There was a significant decrease in hippocampal and cortex cell apoptosis and a significant increase in the number of neuronal cells in the IRI + ASX group compared to the IRI group alone (p<0.05). The neurological deficit score which was significantly lower in the IRI group compared to the control group was found to be significantly improved in the IRI + ASX group (p<0.05).

CONCLUSION

Astaxanthin protects the brain from oxidative damage and reduces neuronal deficits due to IRI injury.

Neuroprotective roles of total flavones of Camellia on early brain injury andcognitive dysfunction following subarachnoid hemorrhage in rats

The present study was undertaken to explore the role of total flavones of Camellia (TFC) on cerebral injury following subarachnoid hemorrhage (SAH) in rats. We showed that the increase of malondialdehyde (MDA) level in brain tissues, leakages of neuron-specifc enolase (NSE) and lactate dehydrogenase (LDH) from brain tissues to serum at 48 h after SAH were significantly blocked by TFC treatment. Besides, TFC treatment could reduce brain edema and the Bax/Bcl-2 ratio in hippocampal tissues at mRNA and protein levels at 48 h after SAH. In addition, and the reduction of neurological scores at 7d after SAH were significantly inhibited by TFC treatment. We next sought to demonstrate the role of TFC on cognitive rehabilitation and the tau phosphorylation in hippocampal tissues at 30d after SAH. Not surprisingly, cognitive dysfunction and the upregulation of tau phosphorylation at Ser262 (p-tau-Ser262) in hippocampal tissues were markedly reduced by TFC treatment. These findings suggested that TFC has protective effect on SAH-induced EBI and subsequent cognitive dysfunction, which may be related to downregulating the Bax/Bcl-2-related apoptosis pathway and inhibition of tau phosphorylation.

A complex virome including two distinct emaraviruses associated with virus-like symptoms in Camellia japonica

Camellia japonica plants manifesting a complex and variable spectrum of viral symptoms like chlorotic ringspots, necrotic rings, yellowing with necrotic rings, yellow mottle, leaves and petals deformations, and flower color-breaking have been studied since 1940, mainly by electron microscopic analyses; however, a strong correlation between the symptoms and one or more well-characterized viruses was never verified. In this work, samples collected from symptomatic plants were analyzed using the next-generation sequencing technique, and a complex virome composed of members of the Betaflexiviridae and Fimoviridae families was identified. In particular, the genomic fragments typical of the emaravirus group were organized in the genomes of two new emaraviruses species, tentatively named Camellia japonica-associated emaravirus 1 and 2. They are the first emaraviruses described in camellia plants and found in symptomatic plants. At the same time, in both symptomatic and asymptomatic plants, five betaflexivirus isolates were detected that, based on amino acid sequence comparisons, can be considered two new isolates of the recently characterized camellia ringspot-associated virus 1 and 2 (CRSaV-1/2). These recently identified betaflexiviruses associated with C. japonica disease show an unusual hyper-conservation of the coat protein at the amino acid level. The GenBank/EMBL/DDBJ accession numbers of the sequences reported in this paper are MN385581, MN532567, MN532565, MN385582, MN532566, MN385573, MN385577, MN385574, MN385578, MN385575, MN385579, MN385576, MN385580, MN557024, MN557025, MN557026, MN557027, and MN557028.

Platycarya strobilacea leaf extract protects mice brain with focal cerebral ischemia by antioxidative property

The leaf extract of Platycarya strobilacea (PSL) has long been recognized as possessing various health-promoting activities. However, information on its possible protective effects against ischemic stroke is currently lacking. Here, using a mouse model of focal cerebral ischemia (fCI), we studied the protective potential of an oral supplement of PSL. Mice were randomly divided into four groups: SO, a group subjected to a sham-operation; VEH, pretreated with distilled water and subjected to middle cerebral artery occlusion and reperfusion (MCAO/R); PSL-L and PSL-H, pretreated with low (20 mg/kg) and high (100 mg/kg) doses of PSL, respectively, and subjected to the MCAO/R procedure. PSL was administered via an oral route daily for 8 days prior to surgery. We then measured the infarct volumes and sensorimotor deficits and studied the underlying antioxidant mechanisms by quantifying apoptosis, reactive oxygen species (ROS) generation, oxidative damages, and antioxidant enzymes in the ischemic cortex. The results showed a marked attenuation in infarct volume and sensorimotor deficits in both the PSL-L and PSL-H groups when compared with VEH. The terminal deoxynucleotidyl transferase dUTP nick end labeling and the immunohistochemical detection of the cleaved caspase-3 revealed that PSL could reduce cellular apoptosis in the ischemic lesion in a dose-dependent manner. The dihydroethidium-fluorescence, 4-hydroxynonenal, and 8-hydroxyl-2'-deoxyguanosine immunoreactivities in the ischemic lesion were markedly attenuated in the PSL-L group compared with the VEH group, indicating that PSL could attenuate ROS generation and the associated oxidative damage in the ischemic cortex. Finally, western blot results indicated that PSL can upregulate levels of heme oxygenase-1 (HO-1), an antioxidant enzyme, in the lesion area. Together, these results suggest that PSL can exert protective effects against fCI, and the mechanism may involve HO-1 upregulation.