ABSTRACT
Aim To investigate the absorption characteristics of gallic acid in the intestine, and to provide a theoretical basis for improving the bioavailability of tannins. Methods Single-pass intestinal perfusion (SPIP) model was used for rat in situ and HPLC to determine the concentration of gallic acid. The absorption rate constant Ka and effective apparent permeability coefficient Peff of gallic acid in each intestinal segment were calculated. The effects of different intestinal segments, drug concentrations, pH value, P-glycoprotein (P-gp), and multidrug resistance protein2 (MRP2) on intestinal absorption were assessed. Results The absorption rate constant (Ka) of gallic acid decreased following the sequence of jejunum > duodenum > ileum ≈ colon. With the increase of drug concentration, there was no significant difference in the absorption of gallic acid. The acidic environment (pH 5. 5) was conducive to the absorption of gallic acid. After the addition of P-gp and MRP2 inhibitors, the absorption of gallic acid was significantly different from that without P-gp and MRP2 inhibitors (P < 0. 05). Conclusions Gallic acid can be well absorbed in the intestine of rats, and is best absorbed in jejunum. The absorption mechanism is determined to be passive diffusion. The gallic acid absorption process is affected by the efflux of P-gp and MRP2, which may be the P-gp and MRP2 substrates.
ABSTRACT
Objective: A urinary metabonomics method based on liquid chromatography-mass spectrometry (HPLC-MS) was used to inspect the effect of tannins from Granati Pericarpium on endogenous metabolism of rats with glomeruloscerosis, the potential biomarkers were searched and the metabolic pathways were analyzed to provide relevant theory for treatment of glomeruloscerosis. Methods: Forty-eight SD rats were divided into control group, model group, benazepril hydrochloridec group, and three doses of pomerganate tannis groups. Glomerular sclerosis model was established by unilateral nephrectomy combined with two tail iv adriamycin; 24 h urine of rats was collected after the rats were orally given tannins from Granati Pericarpium for 8 weeks; HPLC-MS was used for testing and analyzing the urine; Principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used for data treatment of each group to search the potential biomarkers and build the metabolicomics pathways. Results: The urinary metabolism of rats was clustering. Ten potential biomakers were screened by analysis and identification of important variables; The metabonomics pathways involved tryptophan, alanine, aspartate, glutamate metabolism, etc. Conclusion: The trend of endogenous metabolism of rats with glomeruloscerosis is normal after intervened by tannis in pomegranate tannins from Granati Pericarpium. It provides the basement with the further research of clarifying the mechanism of tannins from Granati Pericarpium inpacting on rats with glomeruloscerosis.
ABSTRACT
Ellagitannins is a kind of phenolic compounds with many biological activities. Recent studies have found that the effective ingredients of these compounds have close relationship with their colon-derived bacteria metabolites, that is urolithins. The objective of this study was to review the structure characteristics, types and distribution of urolithins, improvement in diseases related to prostate, breast and colon, as well as anti-cancer, anti-oxidation, anti-inflammation and other biological activities. The present review will lay the foundation for development and utilization of urolithins.
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OBJECTIVE: To study the in vivo metabolism of granatum tannins by liquid chromatography-mass spectrometry and clarify their metabolic pathways. METHODS: The rat urine samples were collected after intragastric administration of tannins preparation of Punica granatum L. husk. The analysis was performed on a Venusil MP-C18 column with gradient elution system of acetonitrile and water containing 0.1% formic acid. Using electrospray ionization (ESI) in negative ion mode with scanning range from m/z 100 to 1000, the metabolites were identified by comparing the MS spectra and MS data with the literatures. RESULTS: Seven metabolites were detected in the rat urine, among which six were identified according to their second mass spectra to be U-1 (urolithin B), U-2 (urolithin A methyl ether), U-3 (urolithin A), U-4 (urolithin A glucuronide), U-5 (ellagic acid) and U-6 (urolithin C). CONCLUSION: Tannins in Punica granatum L. husk are metabolized after oral administration mainly through hydrolysis, glucuronidation gly-cosidation, decomposition and methylation reaction to generate a series of derivatives of urolithin. These results preliminarily indicate the metabolic pathway and material basis of the pharmacological activity of tannins in Punica granatum L. husk in rats.
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Objective: To study the improvement of tannins from Granati Pericarpium on renal fibrosis in rat. Methods: SD rats were randomly divided into five groups, Sham operation, model, Valsartan, high-dose (60 mg/kg), and low-dose (20 mg/kg) tannins groups. Renal fibrosis model of rats was constructed using left ureter ligation method except the rats in the Sham operation group in which the left side ureter of rats was not ligated or cut. The ig administration started at the day of operation, Urinary protein of 24 h, the concentration of Ca2+ and P3+ in urine, and the levels of Scr and BUN in serum were detected in 1-3 week after the operation. The staining of HE and Masson to the kidney tissue was carried out to investigate how tannins from Granati Pericarpium could impact the indexes of renal fibrosis in rats on the morphological basis. Results: The results of urine and blood test showed that the levels of urine protein, Scr, and BUN were deviated from the normal level. The concentration of Ca2+ was increased, while the concentration of P3+ was reduced. The staining of HE and Masson showed that the renal tissue was damaged, the left side of kidney was found renal fibrosis, tannins from Granati Pericarpium could improve the renal fibrosis in rats in some extent. Conclusion: Tannins from Granati Pericarpium have the great improvement on the renal fibrosis in rats and are able to adjust the disorders of Ca2+ and P3+ in rats.