Investigation of serum amino acids involved in gallic acid detoxification of formaldehyde by liquid chromatography/tandem mass spectrometry and neutral loss scan.

RATIONALE: Gallic acid is one of the most common polyphenols in natural products and human diet. The consumption of gallic acid reduces the incidence of cardiovascular diseases, chronic metabolic disorders and cancers. Most previous publications focused on the antioxidative or prooxidative properties of gallic acid. In the present work, gallic acid as a trapping agent of blood formaldehyde was investigated by liquid chromatography/tandem mass spectrometry (LC/MS/MS) and neutral loss scan. METHODS: Serum samples incubated with gallic acid were subjected to LC/MS/MS analysis using an LTQ XL ion trap mass spectrometer. The adduct ions of gallic acid-formaldehyde-amino acids were explored by investigation of their fragmentation patterns and neutral loss scan experiments. RESULTS: A series of Mannich adducts (namely, gallic acid-formaldehyde-alanine, gallic acid-formaldehyde-proline, gallic acid-formaldehyde-leucine or gallic acid-formaldehyde-isoleucine and gallic acid-formaldehyde-phenylalanine) were identified as metabolites by neutral loss scan experiments. CONCLUSIONS: This work demonstrated that serum amino acids are involved in gallic acid detoxification of formaldehyde. Because excessive formaldehyde in blood is implicated in a variety of disease pathologies, detoxification of formaldehyde, especially endogenous formaldehyde, may be another health beneficial effect of gallic acid. It also suggested that more attention should be paid to Mannich-type metabolites of polyphenol-formaldehyde-amino acids in research into the pharmacokinetics and bioavailability of polyphenols.

Effects of First High-Dose Atorvastatin Loading in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Percutaneous Coronary Intervention.

To determine the effects of 80-mg atorvastatin administration for the first time in patients with acute ST segment elevation myocardial infarction (STEMI) before emergency percutaneous coronary intervention (PCI). A total of 118 patients with STEMI who underwent emergency PCI were enrolled in this study. The patients were divided into 80-mg group (n = 59) and 40-mg group (n = 59), according to the loading dose of atorvastatin firstly before operation. The occurrence of no-reflows and changes of HbA1c were observed preoperatively and postoperatively on second and fifth days. All patients were followed up for 1 year with major adverse cardiac events (MACE) recorded. The incidence of no-reflow in 80-mg group was obviously lower than in 40-mg group (13.56% vs. 25.42%) (χ = 4.374, P = 4.374). The preoperative HbA1c levels exhibited no significant difference between 80-mg group and 40-mg group (P > 0.05). The postoperative HbA1c levels in 2 groups showed a trend of gradual decline, which were lower in 80-mg group than in 40-mg group for second day, fifth day, first month, sixth month, and 12th month (all P < 0.05). The postoperative incidence of MACE in 80-mg group was significantly lower than in 40-mg group for sixth and 12th months (both P < 0.05). The incidence of MACE in patients with reflow in 80-mg and 40-mg groups was significantly higher than in patients with no-reflow who were in 80-mg and 40-mg groups for postoperative 12th month (both P < 0.05). The first loading high dose of atorvastatin can significantly prevent occurrence of postoperative no-reflow in patients with STEMI after PCI, reduce HbA1c levels and the incidence of MACE. Clinical randomized controlled trial with larger sample size is required to confirm this finding.

Tanshinone IIA protects against myocardial ischemia reperfusion injury by activating the PI3K/Akt/mTOR signaling pathway.

OBJECTIVE: To determine the mechanism by which Tanshinone IIA (Tan IIA) relieves myocardial ischemia reperfusion injury (MIRI) in rats via the PI3K/Akt/mTOR signaling pathway. METHODS: Sprague-Dawley (SD) rats received an intravenous injection of Tan IIA and LY294002 and were divided into the sham, control (myocardial ischemia reperfusion), Tan-L (low-dose Tan IIA), Tan-H (high-dose Tan IIA), Tan-L+LY (low-dose Tan IIA+LY294002), Tan-H+LY (high-dose Tan IIA+LY294002) and LY (LY294002) groups. Cardiomyocytes obtained from neonatal rats were treated with hypoxia reoxygenatin, Tan IIA and LY294002 and divided into the blank, control, Tan-L, Tan-H, Tan-L+LY, Tan-H+LY and LY groups. Creatine kinase MB isoenzyme (CK-MB) and lactic dehydrogenase (LDH) levels in serum and cardiomyocytes were measured. Area of necrosis/area at risk (AN/AAR) was determined with double staining of TTC and Evan's blue; viability and apoptosis of cardiomyocytes with MTT and TUNEL assays; SOD, MDA, H2O2, SDH and COX levels in heart mitochondria together with PI3K/Akt/mTOR and eNOS expressions and phosphorylation with Western blotting. RESULTS: The Tan-L and Tan-H groups showed a remarkable decrease in AN/AAR, serum CK-MB and LDH, mitochondrial MDA and H2O2 levels but an increase in SOD activity, SDH and COX levels compared with the control group. However, compared with the Tan-L and Tan-H groups, the Tan-L+LY, Tan-H+LY and LY groups indicated an inverse tendency of those indicators. As shown by MTT and TUNEL, the control group had more severe cell damage than the blank group. Furthermore, cell damage and apoptosis were less severe in the Tan-L and Tan-H groups than in the control group, while the Tan-L+LY, Tan-H+LY and LY groups showed an opposite tendency when compared with the Tan-L and Tan-H groups. Meanwhile, the Tan-L and Tan-H groups showed significantly higher expression levels of PI3K, p-Akt/Akt, mTOR and p-eNOS/eNOS than the control group, whereas the Tan-L+LY, Tan-H+LY and LY groups had lower expression levels than the Tan-L and Tan-H groups. CONCLUSION: Our study provided evidence that Tan IIA could activate the PI3K/Akt/mTOR signaling pathway to relieve MIRI in rats.