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The objective of this study was to investigate the therapeutic effect of seawater pearl powder (SPP) on ultraviolet (UV) irradiation-induced photoaging in mouse skin. The protein and trace elements in SPP were detected by liquid chromatography-mass spectrometry, atomic fluorescence spectrometry, and inductively coupled plasma-atomic emission spectrometry. The effect of SPP on treating skin damage resulting from UV-induced photoaging was observed by gross physical appearance and histopathological analysis. Oxidative stress and melanin synthesis were analyzed using biochemical method. Western blotting was applied to analyze the phosphorylation and expression levels of matrix metalloproteinase-1 (MMP-1), collagen I, and proteins involved in the mitogen-activated protein kinase (MAPK) signaling pathways (p38, ERK, and JNK). The results show that SPP has a significant therapeutic effect on UV-induced photoaging of skin and improves and restores appearance and tissue structure of mouse skin. The major mechanism may be related to reduction of expression level of MMP-1 and enhancement of collagen I production via inhibition of MAPK signaling pathway after scavenging of excess reactive oxygen species (ROS) in the UV-induced photoaged skin of mice. Meanwhile, it may also be involved in reducing melanin content by inhibiting tyrosinase activity after scavenging excess ROS in the UV-induced photoaged skin of mice. Therefore, SPP could be a good substance to treat photoaging skin. Taking cost-effectiveness and efficacy into consideration, the optimal concentration of SPP for treating photoaging skin could be 100 mg/g.

This paper uses the China Global Investment Tracker database to map the investment panels of 31 countries along the “Belt and Road” in China, using the system GMM (generalised method of moments) estimation method to study the impact of host country corruption on Chinese OFDI (outward foreign direct investment). The conclusion is that the level of corruption in the host country and the Chinese OFDI total scale show a non-linear “U” relationship. From the perspective of intensive margin, the relationship between host country corruption and the average amount foreign investment from Chinese enterprises is not significant. From the perspective of extensive margin, corruption and the number of enterprises setting up factories in the host country also show U-shaped relationship, but the relationship with the number of investment industries is not significant.

Docosahexaenoic acid (DHA, 22:6n-3), a long-chain polyunsaturated fatty acid (PUFA) with important functions in normal human retinal activity and vision development, is recommended to promote brain and eye development. However, recent research has revealed that increased DHA level in the retina due to linoleic acid-rich diet heightens the vulnerability of the retina to photooxidative stress. Thus, many scholars have analyzed the potential risks of DHA intake on retinal damage. This study evaluated the potential adverse effects of DHA intake on individuals usually exposed to high-light intensity conditions using a visible light-induced retinal pigment epithelium (RPE) cell damage model in vitro. Results showed that DHA promoted the proliferation of RPE cells without any cytotoxicity under dark conditions. However, DHA supplement elicited deleterious effects on RPE cells under high-intensity light conditions. That is, DHA supplement inhibited cellular proliferation, destroyed cell membrane integrity, enhanced cellular senescence, increased vascular endothelial growth factor (VEGF) release, and decreased phagocytic function. Moreover, DHA supplement increased the intracellular and extracellular levels of reactive oxygen species and the extracellular level of lipid peroxidation products under high-intensity light conditions. These results demonstrate that DHA increases the vulnerability of the retina to light damage through lipid peroxidation.

Numerous studies have shown that anthocyanins usually have better in vitro bioactivity than in vivo bioactivity. This may be due to physiochemical degradation during gastrointestinal digestion and their poor bioavailability in in vivo studies. Therefore, this study aims to investigate the effects of anthocyanin structure on their stability under simulated gastrointestinal digestion and to assess their absorption in the intestines using Caco-2 human intestinal cell monolayers. The results show that gastric digestion does not significant affect blueberry anthocyanins in terms of composition and antioxidative activity. However, approximately 42% of the total anthocyanin and 29% of the antioxidative activity were lost during intestinal digestion. Structural analysis indicated that fewer free hydroxyl groups and more methoxy groups in the B-ring improve anthocyanin stability. The absorption trials demonstrated that more hydrophobic anthocyanins have better absorption efficiency than more hydrophilic anthocyanins. Furthermore, the glycoside structure also determines the absorption efficiency of anthocyanins.