Protective effects of silibinin against ethanol- or acetaldehyde-caused damage in liver cell lines involve the repression of mitochondrial fission.

Silibinin is a natural polyphenolic flavonoid, isolated from the seeds of the milk thistle of Silybum marianum (L.) Gaertn. Silibinin has been widely used clinically as a traditional medicine for liver diseases. This study investigated the protective role of silibinin in ethanol- or acetaldehyde-induced apoptosis in human carcinomatous liver HepG2 cells and immortalized liver HL7702 cells, focusing on elucidation of the underlying mechanism in vitro. The toxicity of ethanol or acetaldehyde was evaluated by MTT assay. Apoptosis-related proteins, mitochondrial fission-associated proteins and mitochondrial fusion-associated proteins were analyzed by western blotting and immunofluorescence microscopy. Present experimental results demonstrated that silibinin improved cell viability, reduced the enzyme activities of AST/ALT and ALDH/ADH, inhibited apoptosis and recovered mitochondrial function in ethanol- or acetaldehyde-treated HepG2 or HL7702 cells. Silibinin reduced the expression of mitochondrial fission-associated proteins, dynamin-related protein 1 (DRP1), but increased mitochondrial fusion-associated proteins, optic atrophy 1 (OPA1) and mitofusin 1 (MFN1). Accordingly, inhibition of DRP1 activity with its pharmacological inhibitor or siDRP1 efficiently attenuated ethanol- or acetaldehyde-induced apoptosis, whereas activation of DRP1 by using staurosporine (STS) further increased apoptosis in ethanol- or acetaldehyde-treated HepG2 or HL7702 cells. The results show that silibinin protects cells against ethanol- or acetaldehyde-induced mitochondrial fission that results in apoptosis.

Seven new neuroprotective sesquineolignans isolated from the seeds of Crataegus pinnatifida.

The investigation of the ethanol extract of the seeds of Crataegus pinnatifida led to the isolation of seven new 8-O-4' type sesquineolignans crasesquineolignan A-G (1-7), along with a reported analogue, leptolepisol B (8). The chemical structures of these compounds were elucidated based on complex analysis of their MS, 1D and 2D NMR data. All the isolated compounds were tested for their neuroprotective effects against the damage of human neuroblastoma SH-SY5Y cells induced by H2O2, and most of them showed significant neuroprotective activity. Among them, compound 4 (77.58%) showed the best protective effect, even better than the positive control (69.26%) at 25 µM.

Timosaponin AIII: A novel potential anti-tumor compound from Anemarrhena asphodeloides.

Timosaponin AIII, a major steroidal saponin found in Anemarrhena asphodeloides Bge., which has been widely used as anti-pyretic, anti-diabetic, anti-inflammatory, anti-platelet aggregator and anti-depressant agents in traditional Chinese medicine. Recent pharmacological study showed that timosaponin AIII had potent cytotoxicity, which was potential to be developed as an anticancer agent, however the molecular mechanism underlying the anticancer activity has not been fully elucidated. This review aims to give a systematic summary of the study of timosaponin AIII to reveal its anti-tumor activities by investigating invasion and migration, apoptosis, autophagy and reversing multi-drug resistance. Furthermore, we also make an overview of the mechanisms identified till now. These meaningful findings may provide novel insights on exploiting timosaponin AIII as a new anti-tumor agent.

Neuroprotective Effects of 1,2-Diarylpropane Type Phenylpropanoid Enantiomers from Red Raspberry against H2O2-Induced Oxidative Stress in Human Neuroblastoma SH-SY5Y Cells.

Red raspberry (Rubus idaeus L.) is an edible fruit-producing species belonging to the Rosaceae family. In our search for the health-promoting constituents from this fruit, four pairs of enantiomeric phenylpropanoids (1a/1b-4a/4b), including three new compounds (1a and 2a/2b), were isolated from red raspberry. Their structures were elucidated by a combination of the extensive NMR spectroscopic data analyses, high-resolution electrospray ionization mass spectrometry and comparison between the experimental measurements of electronic circular dichroism (ECD) and calculated ECD spectra by time-dependent density functional theory (TDDFT). In addition, their neuroprotective effects against H2O2-induced oxidative stress in human neuroblastoma SH-SY5Y cells were investigated, and the results showed enantioselectivity, in which that 3a exhibited noticeable neuroprotective activity, while its enatiomer 3b exhibited no obvious protective effect. Further study demonstrated that 3a could selectively inhibit the apoptosis induction and reactive oxygen species (ROS) accumulation by enhancing the activity of catalase (CAT) in H2O2-treated human neuroblastoma SH-SY5Y cells. These findings shed much light on a better understanding of the neuroprotective effects of these enantiomers and provide new insights into developing better treatment of neurodegenerative diseases in the future.

Seven new sesquineolignans isolated from the seeds of hawthorn and their neuroprotective activities.

Seven new sesquineolignans (1-7) were isolated from the 70% ethanolic extract of the hawthorn seeds. Their structures were established by comprehensive spectroscopic analyses including 1D, 2D NMR, CD and HRESIMS data. The neuroprotective activity of the isolated sesquilignans towards H2O2-induced damage in human neuroblastoma SH-SY5Y cells was investigated. All of these sesquineolignans exhibited significant neuroprotective activity towards damaged SH-SY5Y cells, compared with the positive control (Trolox). Among them, 6 displayed the most potent neuroprotective ability with the survival rate of 90.74% at the concentration of 50µM. Moreover, Hoechst 33258 staining and Annexin V/PI analysis proved that 6 could protect damaged SH-SY5Y cells through inhibiting cellular apoptosis.

Effect of hyperbaric oxygen preconditioning on spleen lymphocytes and cell adhesion molecules after skin transplantation in mice.

The aim of this study was to explore the effect of hyperbaric oxygen (HBO) preconditioning on the rejection of skin allograft in mice and its molecular mechanism. BALB/c donor mice and C57BL/6 recipients received hyperbaric oxygen preconditioning once a day for 7 days. After skin transplantation, the recipients were treated with cyclosporine A (CsA) intraperitoneally. Immunofluorescent staining technique and flow cytometry were used to observe the influence HBO on percentage of spleen lymphocytes CD3+, CD4+, CD8+ and cell adhesion molecule LFA-1 (CD11a/CD18). The results showed that as compared with control, the numbers of CD3+, CD4+, CD8+, CD4+CD11a+, CD4+ CD18+, CD8+CD11a+, CD8+CD18+ lymphocytes of spleen decreased in HBO preconditioning groups and CsA group, and decreased markedly in HBO preconditioning combined with CsA group (p<0.05); the general state of recipient mice in HBO preconditioning combined with CsA group was better than that of recipient mice received HBO preconditioning or CsA only. It is concluded that the method of HBO preconditioning combined with traditional immunosuppressive agent CsA has remarkable advantage in inhibiting the rejection of skin graft. Its molecular protective mechanism is correlated with the expression of adhesive molecules on T cell subsets.

Effect of hyperbaric oxygen on acute graft-versus-host disease after allogeneic bone marrow transplantation.

The objective of this study was to investigate the function and mechanism of hyperbaric oxygen (HBO) in antagonizing acute graft-versus-host disease (aGVHD) and improving the rate of survival. The lethally irradiated C57BL/6 recipients were injected with bone marrow and lymphocyte of spleen from BALB/c donors and were treated with HBO, cyclosporine A (CsA) and methotrexate (MTX). T lymphocytes and subsets, adhesion molecules and cytokines were detected by flow cytometry, ELISA and RT-PCR respectively. The results showed that the survival rate in HBO group was much higher than that in allogenetic bone marrow transplantation (allo-BMT) group and CsA + MTX group; the numbers of CD3(+), CD4(+), CD8(+), CD4(+)CD11a(+), CD4(+)CD18(+), CD8(+)CD11a(+), CD8(+)CD18(+) lymphocytes in spleen were decreased markedly by HBO and CsA + MTX (p < 0.05); the levels of IL-2 and TNFalpha mRNA and their serum concentrations in HBO group were much lower than those in allo-BMT group but were higher than those in CsA + MTX group; the levels of IL-4 and IL-10 mRNA in HBO group were much higher than those in allo-BMT group and CsA + MTX group. It is concluded that HBO has more remarkable advantage in improving the rate of survival than CsA + MTX, its mechanism of anti-aGVHD is tightly correlated with the transform of T cell and its subsets and the expression of adhesion molecules and cytokines.