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[Display omitted] • Novel 25 dehydroabietic acid derivatives. • D1 shows the strongest relaxation effect in vitro and in vivo. • D1 has multi-targets effect. Using dehydroabietic acid as the lead compound for structural modification, 25 dehydroabietic acid derivatives were synthesized. Among them, compound D1 not only showed the strongest relaxation effect on the aortic vascular ring in vitro (Emax = 99.5 ± 2.1%, EC 50 = 3.03 ± 0.96 µM), but also significantly reduced systolic and diastolic blood pressure in rats at a dose of 2.0 mg/kg in vivo. Next, the vascular protective effect of the best active D1 and its molecular mechanism were further investigated by HUVECs. The results showed that D1 induced endothelium-dependent diastole in the rat thoracic aorta in a concentration-dependent manner. Endothelium removal or aortic ring pretreatment with NG-nitro- l -arginine methylester (l -NAME), 1 H -[1,2,4]-oxadiazolo-[4,3-a]-quinoxalin-1-one (ODQ), and tetraethylammonium (TEA) significantly inhibited D1 -induced relaxation. In addition, wortmannin, KT5823, triciribine, diltiazem, BaCl 2 , 4-aminopyridine, indomethacin, propranolol, and atropine attenuated D1 -induced vasorelaxation. D1 increased the phosphorylation of eNOS in HUVECs Furthermore, D1 attenuated the expression of TNF-α-induced cell adhesion molecules such as ICAM-1 and VCAM-1. However, this effect was attenuated by the eNOS inhibitors l -NAME and asymmetric dimethylarginine (ADMA). The findings suggest that D1 -induced vasorelaxation through the PI3K/Akt/eNOS/NO/cGMP/PKG pathway by activating the K Ca , K ir and K V channels or muscarinic and β-adrenergic receptors, and inhibiting the l -type Ca2+ channels, which is closely related to the hypotensive action of the agent. Furthermore, D1 exhibits an inhibitory effect on vascular inflammation, which is associated with the observed vascular protective effects. [ABSTRACT FROM AUTHOR]

[Display omitted] • MgIG mitigated LPS-induced liver damage by inhibiting apoptosis and inflammation. • MgIG increased the expression of IL-22 in LPS-induced mice. • MgIG inhibited TLR4/NF-κB pathways and induced autophagy in LPS-treated mice. • MgIG has hepatoprotective effects partially by IL-22-activated autophagy. Liver disease has become a major cause of premature mortality worldwide. It is well known that dysregulated inflammation response plays a crucial role in most liver diseases. As a Chinese medicinal herb, Magnesium isoglycyrrhizinate (MgIG) has been proven to have good hepatoprotective activity and has been used in clinic to treat liver disease. However, the mechanisms by which MgIG regulates LPS-induced liver injury and inflammation in vivo remain elusive. In our study, MgIG pretreatment mitigated LPS-induced liver damage by suppressing apoptosis and inflammation via regulating macrophage/neutrophil infiltration. MgIG ameliorated the effects of LPS on pro-oxidant enzymes (NOX1/2/4) and anti-oxidant enzymes (SOD1/2). Interestingly, we found that the level of the hepatoprotective cytokine interleukin (IL)–22 was significantly upregulated in MgIG-treated liver tissues, which might be a potential mechanism of MgIG against liver injury. Moreover, we found that MgIG treatment not only inhibited TLR4/MyD88/NF-κB signaling pathway, but also activated autophagy. Furthermore, IL-22 treatment activated autophagy and inhibited TLR4/NF-κB signaling pathway in vitro , suggesting that IL-22-activated autophagy and -inhibited inflammation also participated in the protective effects of MgIG. Altogether, our results uncovered the potential mechanisms of the hepatoprotective effects of MgIG, which provided critical evidence to support the use of MgIG to prevent and treat liver diseases. [ABSTRACT FROM AUTHOR]