The Potential Protective Effect of Iridoid Glycosides Isolated From Osmanthus fragrans Seeds Against the Development of Immune Liver Injury in Mice.

Objective: The iridoid glycosides were extracted and separated from Osmanthus fragrans seeds, and the potential protective effect of Osmanthus fragrans seed extract on concanavalin A-induced immune liver injury in mice was studied. Methods: Osmanthus fragrans seeds were extracted by 95% ethanol reflux. Then, the iridoid glycosides were enriched by extraction refined through petroleum ether (60°C-90°C), ethyl acetate, and water-saturated n-butanol in sequence, so as to purify the n-butanol part (Osmanthus fragrans seed's n-butanol extraction, OFSN) by macroporous resin. Specnuezhenide and Nuezhenoside G13 were used as the reference substances to determine the concentration of iridoid glycosides by HPLC. On this basis, a mouse immune liver injury model was established by tail intravenous concanavalin A (20 mg/kg); the contents of serum ALT, AST, IFN-γ, and TNF-α and the contents of liver tissue MDA and SOD were determined; the pathological changes of the liver by HE staining were observed; and the expression levels of p38MAPK and p-p38mapk in liver tissue were detected by WB. Results: The linearity, precision, repeatability, recovery, and stability of HPLC all met the requirements by validating with the methodology. The contents of Specnuezhenide and Nuezhenoside G13 in the n-butanol extracts were 39.20% and 39.88%, respectively. Actually, their contents can reach up to 82.56% and 87.9% after being purified by macroporous resin. The results of animal experiments show that OFSN could significantly reduce the liver and spleen index, reduce the ALT and AST contents in plasma and the MDA content in liver tissue, and then increase the SOD content. Besides, OFSN could also reduce the plasma IFN-γ and TNF-α levels. The HE staining result indicates that the pathological changes in the liver tissues of mice treated with OFSN are alleviated to different degrees while the WB result suggests that OFSN could significantly inhibit the expression of p-p38mapk. Conclusion: Osmanthus fragrans seeds are rich in iridoid glycosides, which has a good protective effect on mouse immune liver injury caused by concanavalin A. The mechanism may be related to inhibiting the phosphorylation of p38MAPK, inhibiting the release of inflammatory mediators, improving the antioxidant capacity of liver cells, and weakening the occurrence of lipid peroxidation.

Hawthorn Leaf Flavonoids Protect against Diabetes-Induced Cardiomyopathy in Rats via PKC-α Signaling Pathway.

OBJECTIVES: DCM has become one of the main reasons of death in diabetic patients. In this study, we aimed to explore the hawthorn leaf flavonoids (HLF) protective effect against diabetes-induced cardiac injury and the underlying mechanisms in experimental rats. METHODS: Experimental diabetic model was induced by intraperitoneal injection of streptozotocin (STZ, 40 mg/kg) in rats after feeding with high-fat diet for 8 weeks. The diabetic rats received a 16-week treatment of different doses of HLF (50, 100, and 200). The morphological changes of myocardial cells were observed by light microscope; the concentration of antioxidant indicator and TNF-α and the expression of PKC-α mRNA, PKC-α, and NF-κB proteins were assessed as well. RESULTS: STZ-induced diabetes mellitus prompted blood glucose, cardiac injury, oxidative stress, and inflammation, accompanied with suppressed body weight. On the contrary, HLF administration improved body weight and blood glucose and attenuated myocardial structural abnormalities in diabetic rats. In addition, HLF decreased MDA level and enhanced SOD activities, inhibited TNF-α expression, and downregulated PKC-α mRNA, PKC-α, and NF-κB which were induced by diabetes. CONCLUSIONS: HLF has a protective effect against diabetic cardiomyopathy in rats. The mechanism may be involved in reducing oxidative stress and inflammation via inactivation of the PKC-α signaling pathway.

Metabonomics study on Polygonum multiflorum induced liver toxicity in rats by GC-MS.

Polygonum multiflorum, a traditional Chinese medicinal herb, is widely used in liver and liver nourishing. Recent years, drug regulatory departments reported that Polygonum multiflorum caused serious adverse reaction in clinic, especially liver injury. In this study, we detected the changes in rat serum and liver tissue metabolites through gas chromatography-mass spectrometry (GC-MS). Mass spectrometry, partial least squares-discriminate analysis (PLS-DA) and other diversified techniques were used to analyze the differences among their metabolites. Compared to the control group, the serum concentrations of L-threonine and serine in water extraction groups increased. The serum concentrations of 9,12-octadecadienoic acid, hexadecanoic acid, oleic acid, D-glucose and octadecanoic acid in alcohol extraction groups increased, while lactic acid decreased to a great extent. For liver tissue, compared to the control group, the concentrations of myo-inositol, oleic acid and cholesterol in water extraction groups increased, while those of hexadecanoic acid, octadecanoic acid, ribitol and butanedioic acid decreased to a great extent. The concentrations of myo-inositol, phosphoric acid, uridine, oleic acid, cholesterol and butanoic acid in alcohol extraction groups increased to a great extent, while those of hexadecanoic acid, octadecanoic acid, ribitol and butanedioic acid decreased. The results indicate that Polygonum multiflorum induces the metabolic disorders of energy metabolism, amino acid and lipid metabolism. What's more, liver injury of alcohol extraction group was more serious than group of water extraction.

Effects of Polygonum multiflorum on the activity of cytochrome P450 isoforms in rats.

Polygonum multiflorum is a traditional Chinese medicinal herb used in clinical medicine to nourish the liver and kidney. However, in recent years, there have been increased reports of clinical adverse reactions associated with Polygonum multiflorum preparations, especially due to liver injury. The cocktail method can be used to assess the influence of Polygonum multiflorum on the activity of cytochrome P450 (CYP450) isoforms CYP2B6, CYP2C19, CYP2C9, CYP1A2, CYP3A4, and CYP2D6, which were reflected by changes in pharmacokinetic parameters in six specific probe drugs: bupropion, omeprazole, tolbutamide, phenacetin, midazolam, and metoprolol. Comprised the experimental rats were randomly divided into five groups: control group, alcohol extraction A group, alcohol extraction B group, water extraction A group, and water extraction B group. Each group five male rats and five female rats. Each of the groups received treatments by gavage as follows: control group was given normal saline, alcohol extraction A group was given 15 g/kg alcohol extract of Polygonum multiflorum (E15), alcohol extraction B group was given with 30 g/kg alcohol extract (E30), water extraction A group was given 15 g/kg water extract (W15), and water extraction B group was given 30 g/kg water extract (W30). The extract solution was orally administered once a day for 28 consecutive days. The mixture of six probe drugs was given by gavage, and blood samples were collected through the tail vein at different time points. Probe drug concentration in rat plasma was measured by liquid chromatography-mass spectrometry (LC-MS). In the treatment and control groups, Polygonum multiflorum alcoholic extract inhibited the activity of CYP2C19 and CYP2C9 and induced the activity of CYP1A2. Polygonum multiflorum aquous extract inhibited the activity of CYP2B6, CYP2C19, CYP2C9, CYP1A2, and CYP2D6. Pathological sections showed that in the alcohol extract group the liver was degenerated inconspicuously, and in the water extract group, the cytoplasm had vacuoles and particulate matter. The arrangement of liver cells was irregular.