Spatio-temporal characteristics and multi-scenario simulation analysis of ecosystem service value in coastal wetland: A case study of the coastal zone of Hainan Island, China.

Coastal wetland ecosystems harbor rich biodiversity and possess significant ecosystem service value (ESV). Therefore, it offers a range of crucial ecosystem services (ES) for human well-being and socio-economic development. Taking the Hainan Island coastal zone (HICZ) as a case study, the spatio-temporal characteristics of land use and land cover change (LULCC), and its associated ESV in wetland landscapes were analyzed over three time points (2000, 2010 and 2020). We explored the spatio-temporal evolution trajectory of ESV on the basis of geo-information tupu. Then, future land use simulation (FLUS) was employed to predict wetland patterns and ESV under three different scenarios: business as usual (BAU), ecological conservation first (ECF), and economic development first (EDF). The results showed that over the past two decades, a significant proportion (exceeding 80%) of the overall wetland region was comprised of offshore and coastal wetlands (OCW) as well as constructed wetlands (CW); these formed the matrix of the landscape. The area of building land (BL) continued to exhibit a consistent upward trend. Expanding by 2.18 times, it represented the most significant increase in the rate of dynamic changes in BL. The main ES in the HICZ corresponded to the regulation services (53.57%) and the support services (27.58%). The ESV of wetland losses accounted for 45.17% (43.08 × 108 yuan) of the total loss. The spatial differentiation of ESV in the HICZ was larger in the southwest and the northeast regions, while it was comparatively lower in the north. The transformation in the area of early and late change types accounted for 236.46 km2 and 356.69 km2, respectively. The scenario ECF was achieved with an optimal development of ESV (1807.72 × 108 yuan), which was coordinated with the high-level of development of regional ES functions and the economy. These findings provide valuable information for the sustainable development as well as the protection of ecology and environment of the coastal zone under the background of the construction of Hainan pilot free trade zone in the future.

Neuroprotection of rhubarb extract against cerebral ischaemia-reperfusion injury via the gut-brain axis pathway.

BACKGROUND: The gut-brain axis (GBA) plays a central role in cerebral ischaemia-reperfusion injury (CIRI). Rhubarb, known for its purgative properties, has demonstrated protective effects against CIRI. However, it remains unclear whether this protective effect is achieved through the regulation of the GBA. AIM: This study aims to investigate the mechanism by which rhubarb extract improves CIRI by modulating the GBA pathway. METHODS: We identified the active components of rhubarb extract using LC-MS/MS. The model of middle cerebral artery occlusion (MCAO) was established to evaluate the effect of rhubarb extract. We conducted 16S rDNA sequencing and untargeted metabolomics to analyze intestinal contents. Additionally, we employed HE staining, TUNEL staining, western blot, and ELISA to assess intestinal barrier integrity. We measured the levels of inflammatory cytokines in serum via ELISA. We also examined blood-brain barrier (BBB) integrity using Evans blue (EB) penetration, transmission electron microscopy (TEM), western blot, and ELISA. Neurological function scores and TTC staining were utilized to evaluate neurological outcomes. RESULTS: We identified twenty-six active components in rhubarb. Rhubarb extract enhanced α-diversity, reduced the abundance of Enterobacteriaceae, and partially rectified metabolic disorders in CIRI rats. It also ameliorated pathological changes, increased the expressions of ZO-1, Occludin, and Claudin 1 in the colon, and reduced levels of LPS and d-lac in serum. Furthermore, it lowered the levels of IL-1ß, IL-6, IL-10, IL-17, and TNF-α in serum. Rhubarb extract mitigated BBB dysfunction, as evidenced by reduced EB penetration and improved hippocampal microstructure. It upregulated the expressions of ZO-1, Occludin, Claudin 1, while downregulating the expressions of TLR4, MyD88, and NF-κB. Similarly, rhubarb extract decreased the levels of IL-1ß, IL-6, and TNF-α in the hippocampus. Ultimately, it reduced neurological function scores and cerebral infarct volume. CONCLUSION: Rhubarb effectively treats CIRI, potentially by inhibiting harmful bacteria, correcting metabolic disorders, repairing intestinal barrier function, alleviating BBB dysfunction, and ultimately improving neurological outcomes.

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.