Green tea derivative (-)-epigallocatechin-3-gallate (EGCG) confers protection against ionizing radiation-induced intestinal epithelial cell death both in vitro and in vivo.

Radiation-induced intestinal injury (RIII) occurs during instances of intentional or accidental radiation exposure. However, there are few effective treatments available for the prevention or mitigation of RIII currently. (-)-Epigallocatechin-3-gallate (EGCG), a major polyphenol in green tea, possesses potent antioxidant activity and has been shown to be effective in ameliorating many oxidative stress-related diseases. The therapeutic effects and mechanism of EGCG on RIII have not yet been determined. In the present study, we investigated whether EGCG confers radioprotection against RIII. Our data demonstrated that administration of EGCG not only prolonged the survival time of lethally irradiated mice, but also reduced radiation-induced intestinal mucosal injury. Treatment with EGCG significantly increased the number of Lgr5+ intestinal stem cells (ISCs) and their progeny Ki67+ cells, and reduced radiation-induced DNA damage and apoptosis. Besides, EGCG displayed the same radioprotective effects in human intestinal epithelial HIEC cells as in mice, characterized by a decrease in the number of γH2AX foci and ferroptosis. Moreover, EGCG decreased the level of reactive oxygen species (ROS) and activated the transcription factor Nrf2 and its downstream targets comprising antioxidant proteins Slc7A11, HO-1 and GPX4. Treatment with the Nrf2 inhibitor ML385 abolished the protective effects of EGCG, indicating that Nrf2 activation is essential for EGCG activity. Taken together, our findings demonstrated that EGCG protects against RIII by scavenging ROS and inhibiting apoptosis and ferroptosis through the Nrf2 signal pathway, which could be a promising medical countermeasure for the alleviation of RIII.

[Determination of chlorogenic acid and luteoloside in lonicerae flos of different habitats and germplasms].

OBJECTIVE: To establish an UPLC-PDA method for simultaneous determination of chlorogenic acid and luteoloside in Lonicerae Flos. On the basis of developed method, the quality of Lonicerae Flos from nine habitats and two local germplasms introduced from Qufu in Shandong to Wuming in Guangxi was evaluated. METHODS: The analysis was performed on a Waters Acquity UPLC H-Class system. An Acquity UPLC BEH RP18 (100 mm x 2.1 mm,1.7 µm) column was used for all analyses. The investigated compounds were separated with a gradient mobile phase consisting of acetonitrile and 0.4% phosphoric acid solution at a flow rate of 0.2 mL/min, and the detection wavelength was set at 242 nm. RESULTS: The quality of Lonicerae Flos from Qufu was the best among Lonicerae Flos of nine habitats for its content of chlorogenic acid and luteoloside at 35.715 and 1.270 mg/g, respectively. The content of chlorogenic acid and luteoloside in Lonicerae Flos of "Jiufengyihao" and "Shuxing" introduced from Qufu to Wuming both complied with the standard of Chinese Pharmacopoeia (2010 edition). CONCLUSION: The developed UPLC-PDA method is simple, reliable and repeatable, which is helpful for the quality control of Lonicerae Flos. "Jiufengyihao" and "Shuxing" are potential germplasms for the introduction of Lonicerae Flos in Wuming.

[Eosinophils apoptosis, fas mRNA and bcl-2 mRNA expressions in asthma model of young rat and effects of achyranthes bidentata polysaccharides].

OBJECTIVE: Asthma is a chronic respiratory tract disorder characterized by airway hyperreaction (AHR), persistent airway inflammation, high serum IgE, overproduction of IL-4, IL-5 and IL-13 by allergen-specific Th2 cells. The morbidity and mortality of asthma have continued to increase despite the use of currently available therapeutic agents. The reputed effects of traditional Chinese medicines (TCMs) have led to increasing use of TCMs for treatment of asthma throughout the world. The aims of this study were to investigate in asthma model of young rat the mRNA expressions of apoptotic gene fas and bcl-2, eosinophils (EOS) apoptosis in airway, and effects of achyranthes bidentata polysaccharides (ABPS), a group of polysaccharides extracted from TCM Achyranthes bidentata blume, on treatment of asthma. METHODS: Fifty Sprague-Dawley (SD) rats were divided into five groups, 10 rats per group. Asthma in rats was induced by intraperitioneal sensitization and challenge with nebulized ovalbumin (OVA). A pretreatment with ABPS [50 mg/(kg x d)] was done according to three different schedules: consecutively 3 days at sensitization (T1), at challenge (T2) or both of the two periods (T3). Sham-treated rats (A) and naive rats (C) served as controls. The animals were sacrificed 24 hours after the last challenge. The mRNA expression of bcl-2 and fas in eosinophils presenting in airway and the apoptosis of eosinophils in airway were assessed by using in situ hybridization with oligonucleotide probe and TUNEL methods, respectively. RESULTS: (1) Twenty-four hours after the last antigen challenge, the mRNA expression of fas in eosinophils presenting in airway significantly decreased in group A [(43.4 +/- 10.0)%] compared with that in group C [(73.2 +/- 11.9)%] (P < 0.01). ABPS could increase the fas mRNA expression significantly in all the three groups [(59.0 +/- 8.1)%, (57.5 +/- 9.6)%, (76.2 +/- 2.7)%], compared with that in group A (P < 0.05, P < 0.05, P < 0.01, respectively). The expression of the bcl-2 mRNA in group C was (47.9 +/- 8.7)%, it was elevated to (67.4 +/- 7.3)% in group A (P < 0.01). The expression of the bcl-2 mRNA in ABPS treated T1 and T3 groups was significantly lowered [(57.7 +/- 12.7)%, (57.3 +/- 6.8)%, P < 0.05], but not in T2 group [(72.4 +/- 6.7)%]. (2) In group A, the EOS presenting in the airway increased significantly, but there were few apoptotic EOS; the percentage of apoptotic eosinophil was distinctly lower in group A than that in group C [(5.3 +/- 2.2)% vs. (15.9 +/- 2.4)%, P < 0.01]. Compared with that in group A, the eosinophil apoptosis ratio in those ABPS treated groups T1, T3 was evidently elevated [(8.7 +/- 2.9)%, (9.8 +/- 2.2)%, P < 0.05, P < 0.05], but ABPS treated at challenge (T2) could not change the eosinophil apoptosis ratio significantly (P > 0.05). CONCLUSION: (1) In asthmatic rat, the expressions of the genes fas and bcl-2 mRNA in EOS were changed evidently and the ratio of EOS apoptotosis reduced greatly. (2) ABPS could enhance the apoptosis of EOS by upregulating the expression of the genes fas and bcl-2 mRNA.