Preventive Effect of Raw Liubao Tea Polyphenols on Mouse Gastric Injuries Induced by HCl/Ethanol via Anti-Oxidative Stress

Abstract

Liubao tea is a type of traditional Chinese tea, belonging to the dark teas. This study is a basic research of the contained polyphenols (active substances) and detected preventive effects of polyphenols of raw Liubao tea (PRLT) on mouse gastric injuries induced by HCl/ethanol. High-pressure liquid chromatography was used to analyze the components of PRLT. Furthermore, a mouse gastric injury model was established to observe the preventive effects. PRLT was shown to contain gallic acid, EGC (epigallocatechin), catechin, caffeine, EC (epicatechin), EGCG (epigallocatechin gallate), GCG (gallocatechin gallate), and ECG (epicatechin gallate). The results of the in vivo study indicate that PRLT can inhibit the observed increase of gastric juice volume and decrease of gastric juice pH caused by gastric injury. PRLT can decrease the serum levels of IL-6 (interleukin-6), IL-12 (interleukin-12), TNF-α (tumor necrosis factor-α), and IFN-γ (interferon-γ) in mice with gastric injuries. Moreover, it can also increase the serum levels of SS (somatostatin) and VIP (vasoactive intestinal peptide) and reduce the serum levels of both SP (substance P) and ET-1 (endothelin-1). PRLT was also shown to increase SOD (superoxide dismutase) and GSH (glutathione) levels and decrease MDA (malondialdehyde) level. The detection of mRNA and protein in gastric tissues indicates that PRLT could also up-regulate the expression of Cu/Zn-SOD (copper/zinc superoxide dismutase), Mn-SOD (manganese superoxide dismutase), CAT (catalase), nNOS (neuronal nitric oxide synthase), and eNOS (endothelial nitric oxide synthase) and down-regulate the expression of both iNOS (inducible nitric oxide synthase) and COX-2 (cyclooxygenase-2). Thus, PRLT possess a good preventive effect on gastric injury, which is directly related to the contained active substance. PRLT show good anti-oxidative and preventive effect in gastric injury and offer promising application value.

Preventive effect of flavonoids from Wushan Shencha (Malus doumeri leaves) on CCl4‐induced liver injury

“…The supernatant was separated by centrifugation. After two extractions, the supernatant was adjusted to pH 4.0 with 12% hydrochloric acid, and then, the flavonoid extract was obtained by rotary evaporation (R‐1001‐VN; Zhengzhou Greatwall Scientific Industrial and Trade Co., Ltd.) (Qian et al, ).…”

Preventive Effect of Liupao Tea Polyphenols on HCl/Ethanol-Induced Gastric Injury in Mice

“…Once iNOS is activated, the enzymatic activity will last for a long time and produce a large amount of NO. A low concentration of NO can effectively help cells resist gene mutation and can activate the defense ability of the organism, but a high concentration of NO causes loss of gene mutation control, stimulates gene mutation and aggravates tissue damage [26]. LTPs can increase the expression of nNOS and eNOS in the gastric tissue of mice with gastric injury and reduce the expression of iNOS, thus inhibiting the inflammatory response, protecting gastric mucosa, and inhibiting gastric injury.…”

Preventive effect of Lactobacillus plantarum HFY09 on HCl/ethanol-induced gastric injury in mice

“…After the 15th day, the mice were fasted for 24 h and were then treated with induction solution HCl/ethanol solution (60% ethanol and 40% 150 mmol/L HCl mixture) by gavage. The induced dose was 10 mL/kg [5,13]. Except for the normal group, the other groups were given the same dose of HCl/ethanol solution, and the normal group was given the same volume of normal saline.…”

“…Real time fluorescent quantitative PCR (Q-PCR) is a method for measuring the total amount of products after each polymerase chain reaction (PCR) cycle using fluorescent chemicals in a DNA amplification reaction. [13,16]. The objective genes and housekeeper gene were all reacted by fluorescence quantitative PCR to obtain cycle threshold (CT) values, and calculate the relative expression of mRNA in samples by relative comparison and quantitative method (2 −ΔΔCt method) [17,18].…”