Extracts of Ginkgo flavonoids and ginkgolides improve cerebral ischaemia-reperfusion injury through the PI3K/Akt/Nrf2 signalling pathway and multicomponent in vivo processes.

BACKGROUND: Cerebral ischaemia-reperfusion injury (CIRI) is a common disease characterized by severe attacks and a high disabling rate worldwide. Oxidative stress injury has been proposed as a major risk factor for CIRI. Ginkgo biloba extract (GBE) has been shown to elicit vascular protective effects, the main components of which are Ginkgo flavonoids (GF) and ginkgolides (GL). Our previous study showed that GF and GL played a central role in protecting CIRI, but the mechanism remains unclear. This study aimed to further reveal the protective effect mechanism of GF and GL in rats with CIRI. METHODS: The antioxidant activity in vitro was assessed by the DPPH method. The model used in this study was established by middle cerebral artery occlusion (MCAO) and reperfusion; the level of CIRI was assessed by nerve function score and TTC staining; we measured the oxidative stress indices in the brain cortex, including LDH, GSH-Px, and the protein contents of Akt, p-Akt, Nrf2, and HO-1; HPLC-MS was used to detect drug concentrations in rat plasma at different times after administration of GF and GL; and the pharmacokinetic parameters of each component were calculated by Drug and Statistic Version 3.2.6 (DAS 3.2.6) software and SPSS 17.0. RESULTS: Regarding the DPPH free radical scavenging ability, GF performed better free radical scavenging ability than GL. In terms of the nerve function score and TTC staining, there were no statistically significant differences among the GF, GL and combined groups; however, there were significant differences in reducing the activity of LDH and increasing the activity of GSH-Px in the three administration groups. For the expression of Akt, p-Akt, Nrf2, and HO-1, the combined group had a significant effect compared with that in the GF or GL group. In addition, there was a significant multicomponent interaction in vivo in the combined group compared with the GF or GL group. CONCLUSION: After GF and GL were used in combination, the effect of anti-CIRI was more pronounced. This result indicated that GF and GL might improve CIRI by activating the PI3K/Akt/Nrf2 signalling pathway and promoting multicomponent interactions in vivo.

Rhubarb anthraquinone glycosides protect against cerebral ischemia-reperfusion injury in rats by regulating brain-gut neurotransmitters.

Rhubarb anthraquinone glycosides (RAGs) have been proven to have significant therapeutic effects on ischemic stroke, and this effect may be related to the microbiome-gut-brain axis. In this study, an HPLC-FLD method was established to measure brain-gut neurotransmitters of rats with cerebral ischemia-reperfusion injury (CIRI), to explore whether the mechanism of RAGs against CIRI is related to the microbiome-gut-brain axis. A Shimadzu ODS-3 C18 column was used for chromatographic separation, and 5-hydroxytryptamine (5-HT), 5-hydroxy indole acetic acid (5-HIAA), glutamic acid (Glu), aspartic acid (Asp), and γ-aminobutyric acid (GABA) were determined simultaneously. The results showed that there is an excellent linear relationship (R2 ≥ 0.9990) and a high separation degree in the HPLC-FLD method. Whereas the contents of Asp and Glu in the brain and colon increased (p < 0.05), the contents of 5-HT, 5-HIAA, and GABA in the brain and colon decreased (p < 0.05) after CIRI. RAGs could effectively reduce the contents of Asp and Glu (p < 0.05), and increase the contents of 5-HT, 5-HIAA, and GABA in the brain and colon (p < 0.05). Combined with the previous experimental results, we can speculate that RAGs can regulate intestinal flora disorder caused by CIRI, and then regulate the imbalance between the release and decomposition of neurotransmitters caused by intestinal flora disorder.

Protective mechanism of rhubarb anthraquinone glycosides in rats with cerebral ischaemia-reperfusion injury: interactions between medicine and intestinal flora.

BACKGROUND: Anthraquinone glycosides extracted from rhubarb have been proven to have significant therapeutic effects on ischaemic stroke. It is well known that anthraquinone glycosides are not easily absorb. Thus, how can rhubarb anthraquinone glycosides (RAGs) exert protective effects on the brain? Is this protective effect related to interactions between RAGs and intestinal flora? METHODS: The model used in this study was established by middle cerebral artery occlusion (MCAO) and reperfusion. Twenty-seven adult male Sprague-Dawley (SD) rats were randomly divided into 3 groups: the normal group (A) (non-MCAO + 0.5% sodium carboxymethyl cellulose (CMC-Na)), model group (B) (MCAO + 0.5% CMC-Na) and medicine group (C) (MCAO + RAGs (15 mg/(kg day)). The rats were fed by gavage once a day for 7 days. Fresh faeces were collected from the normal group to prepare the intestinal flora incubation liquid. Add RAGs, detect the RAGs and the corresponding anthraquinone aglycones by HPLC-UV at different time points. On the 8th day, the rats were euthanized, and the colonic contents were collected and analysed by high-throughput sequencing. In addition, 12 adult male SD rats were randomly divided into 2 groups: the normal group (D) (non-MCAO + RAGs (15 mg/(kg day)) and model group (E) (MCAO + RAGs (15 mg/(kg day)). The rats were fed by gavage immediately after reperfusion. Blood was collected from the orbital venous plexus, and the RAGs and anthraquinone aglycones were detected by HPLC-UV. RESULTS: The abundance and diversity of the intestinal flora in rats decreased after cerebral ischaemia-reperfusion injury (CIRI). RAGs could effectively improve the abundance of the intestinal flora. In addition, in vitro metabolism studies showed that RAGs were converted into anthraquinone aglycones by intestinal flora. In the in vivo metabolism studies, RAGs could not be detected in the plasma; in contrast, the corresponding anthraquinone aglycones could be detected. Absorption of RAGs may be inhibited in rats with CIRI. CONCLUSIONS: CIRI may lead to intestinal flora disorder in rats, and after the administration of RAGs, the abundance of intestinal flora can be improved. RAGs can be metabolized into their corresponding anthraquinone aglycones by intestinal flora so that they can be absorbed into the blood.

Correction: A multi-center randomized prospective study on the treatment of infant bronchiolitis with interferon α1b nebulization.

[This corrects the article DOI: 10.1371/journal.pone.0228391.].

A multi-center randomized prospective study on the treatment of infant bronchiolitis with interferon α1b nebulization.

BACKGROUND: The respiratory syncytial virus (RSV) is the main cause of bronchiolitis in infants and interferon (IFN) α is a commercial antiviral drug. The nebulization of IFN α1b could be a viable treatment method. In this study, the therapeutic effects and safety of IFN α1b delivery via nebulization in infant bronchiolitis were investigated in this multi-center prospective study. METHODS AND FINDINGS: Bronchiolitis patients admitted to 22 hospitals who met the inclusion criteria were enrolled and randomly allocated to four groups: control, IFN Intramuscular Injection, IFN Nebulization 1 (1 µg/kg), and IFN Nebulization 2 (2 µg/kg) groups. All patients were observed for 7 days. The therapeutic effects and safety of different IFN delivery doses and delivery modes were evaluated. Coughing severity change, as scored by the researchers and parents, between days 1 and 3 was significantly different between the IFN Nebulization 2 and control groups. Lowell wheezing score change between days 3 and 5 was significantly different between IFN Nebulization 1 and control groups. There were no significant differences among the four groups regarding the number of consecutive days with fever, three-concave sign, fatigue and sleepiness, and loss of appetite. There were no cases of severe complications, no recurrence of fever, and no regression of mental status. CONCLUSIONS: IFN-α1b could more effectively alleviate coughing and wheezing in bronchiolitis. IFN-α1b nebulization had significant advantages in shortening the duration of wheezing and alleviating coughing.