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Curcumin (CUR) has antioxidant and anti-inflammatory effects that are beneficial to Alzheimer's disease (AD). However, the poor solubility and high instability of CUR compromise its application greatly. In this study, CUR-encapsulated chitosan-coated poly (lactic-co-glycolic acid) nanoparticles (CUR-CS-PLGA-NPs) and hydroxypropyl-β-cyclodextrin-encapsulated CUR complexes (CUR/HP-β-CD inclusion complexes) were developed and compared through intranasal administration. In vitro studies indicated that CUR in CUR/HP-β-CD inclusion complexes was stable under physiological conditions over 72 h with 95.41 ± 0.01% remaining, which was higher than 49.66 ± 3.91% remaining in CUR-CS-PLGA-NPs. Meanwhile, CUR/HP-β-CD inclusion complexes showed a higher cellular uptake level of CUR than CUR-CS-PLGA-NPs in SH-SY5Y cells. Both formulations could reduce CUR's cellular cytotoxicity and showed a comparable antioxidant effect. Both formulations displayed the anti-inflammatory effect at 20 μM CUR in BV-2 cells, which decreased TNF-α and IL-6 levels to approximately 70 and 40%, respectively, when compared to the positive control, respectively. In vivo pharmacokinetic studies indicated that after intranasal administration, the AUC values of CUR in the plasma and brain of the CUR/HP-β-CD inclusion complex group were 2.57-fold and 1.12-fold higher than those in the CUR-CS-PLGA-NP group at the same dose of 2 mg/kg, respectively. In conclusion, CUR/HP-β-CD inclusion complexes displayed better properties than CUR-CS-PLGA-NPs as a carrier for intranasal delivery of CUR for application in AD.

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A low‐viscosity crustal layer (LVCL) due to partial melt and/or hydration has been detected within the continental crust (e.g., in South China block), but its role in the development of hyperextended margins is still not entirely understood. Using 2‐D thermomechanical modeling, we simulate the lithospheric extension with a LVCL embedded within the continental crust. Results show that the ductile layer determines the width of highly thinned crust and the crustal thermal distribution. Detailed effects are found by varying the initial effective viscosity and thickness of the layer: (1) a rheologically weaker and/or thicker LVCL accommodates more deformation and thus results in a slow and distributed crustal thinning and (2) preferential removal of the lithospheric mantle places the crust in direct contact with the hot upwelling asthenosphere, promoting the development of highly thinned and hot continental crust. Both the widths of highly thinned crust and the thermal values increase when the rheology of the ductile layer decreases or the thickness increases. Furthermore, we obtain the crustal thickness and geothermal characteristics of the northern South China Sea (SCS) margin using reprocessed geophysical data and newly complied heat flow data. A detailed comparison of our modeling results with the northern SCS margin suggests that variation in the LVCL thickness may be a possible mechanism for the differential width of highly thinned crust and high heat flow zone along strike of the northern SCS margin.