Mechanism of N-Methyl-N-Nitroso-Urea-Induced Gastric Precancerous Lesions in Mice.

Early diagnosis and treatment of gastric precancerous lesions (GPL) are key factors for reducing the incidence and morbidity of gastric cancer. The study is aimed at examining GPL in mice induced by N-methyl-N-nitroso-urea (MNU) and to illustrate the underlying mechanisms of tumorigenesis. In this study, we utilized an in vivo MNU-induced GPL mouse model, and histopathological changes of the gastric mucosa were observed by hematoxylin and eosin (H&E-stain) and alcian blue (AB-PAS-stain). The level of miR-194-5p in the gastric mucosa was determined by real-time polymerase chain reaction. We used transmission electron microscopy to observe the effects of MNU on gastric chief cells and parietal cells. We performed immunohistochemical detection of HIF-1α, vWF, Ki-67, and P53, while the changes in the protein expression of key genes in LKB1-AMPK and AKT-FoxO3 signaling pathways were detected by western blot analysis. We demonstrated that the miR-194-5p expression was upregulated under hypoxia in GPL gastric tissues, and that a high miR-194-5p expression level closely related with tumorigenesis. Mechanistically, miR-194-5p exerted the acceleration of activities related to metabolic reprogramming through LKB1-AMPK and AKT-FoxO3 pathways. Furthermore, similar to miR-194-5p, high expression levels of AMPK and AKT were also related to the metabolic reprogramming of GPL. Moreover, we revealed the correlation between the expression levels of miR-194-5p, p-AMPKα, p-AKT, and FoxO3a. These findings suggest that miR-194-5p/FoxO3 pathway is important for the reversal of metabolic reprogramming in GPL. Thus, exploring strategies to regulate the miR-194-5p/FoxO3a pathway may provide an efficient strategy for the prevention and treatment of GPL.

Panax ginseng C.A. Meyer (Rg3) Ameliorates Gastric Precancerous Lesions in Atp4a-/- Mice via Inhibition of Glycolysis through PI3K/AKT/miRNA-21 Pathway.

Gastric cancer, one of the most common types of cancers, develops over a series of consecutive histopathological stages. As such, the analysis and research of the gastric precancerous lesions (GPLs) play an important role in preventing the occurrence of gastric cancer. Ginsenoside Rg3 (Rg3), an herbal medicine, plays an important role in the prevention and treatment of various cancers. Studies have demonstrated a correlation between glycolysis and gastric cancer progression. Herein, the aim of the present study was to clarify the potential role for glycolysis pathogenesis in Rg3-treated GPL in Atp4a-/- mice. The GPL mice model showed chronic gastritis, intestinal metaplasia, and more atypical hyperplasia in gastric mucosa. According to the results of HE and AB-PAS staining, it could be confirmed that GPL mice were obviously reversed by Rg3. Additionally, the increased protein levels of PI3K, AKT, mTOR, HIF-1α, LDHA, and HK-II, which are crucial factors for evaluating GPL in the aspect of glycolysis pathogenesis in the model group, were downregulated by Rg3. Meanwhile, the miRNA-21 expression was decreased and upregulated by Rg3. Furthermore, the increased gene levels of Bcl-2 and caspase-3 were attenuated in Rg3-treated GPL mice. In conclusion, the findings of this study imply that abnormal glycolysis in GPL mice was relieved by Rg3 via regulation of the expressions of PI3K, AKT, mTOR, HIF-1α, LDHA, HK-II, and miRNA-21. Rg3 is an effective supplement for GPL treatment and can be harnessed to inhibit proliferation and induce apoptosis of GPL cells.

Dynamic characterization of intestinal metaplasia in the gastric corpus mucosa of Atp4a-deficient mice.

Parietal cells of the gastric mucosa contain a complex and extensive secretory membrane system that harbors gastric H+, K+-adenosine triphosphatase (ATPase), the enzyme primarily responsible for gastric lumen acidification. Here, we describe the characterization of mice deficient in the H+, K+-ATPase α subunit (Atp4a-/-) to determine the role of this protein in the biosynthesis of this membrane system and the biology of the gastric mucosa. Atp4a-/- mice were produced by gene targeting. Wild-type (WT) and Atp4a-/- mice, paired for age, were examined at 10, 12, 14 and 16 weeks for histopathology, and the expression of mucin 2 (MUC2), α-methylacyl-CoA racemase (AMACR), Ki-67 and p53 proteins was analyzed by immunohistochemistry. For further information, phosphoinositide 3-kinase (PI3K), phosphorylated-protein kinase B (p-AKT), mechanistic target of rapamycin (mTOR), hypoxia-inducible factor 1α (HIF-1α), lactate dehydrogenase A (LDHA) and sirtuin 6 (SIRT6) were detected by Western blotting. Compared with the WT mice, hypochlorhydric Atp4a-/- mice developed parietal cell atrophy and significant antral inflammation (lymphocyte infiltration) and intestinal metaplasia (IM) with elevated MUC2 expression. Areas of dysplasia in the Atp4a-/- mouse stomach showed increased AMACR and Ki-67 expression. Consistent with elevated antral proliferation, tissue isolated from Atp4a-/- mice showed elevated p53 expression. Next, we examined the mechanism by which the deficiency of the H+, K+-ATPase α subunit has an effect on the gastric mucosa. We found that the expression of phosphorylated-PI3K, p-AKT, phosphorylated-mTOR, HIF-1α, LDHA and SIRT6 was significantly higher in tissue from the Atp4a-/- mice compared with the WT mice (P<0.05). The H+, K+-ATPase α subunit is required for acid-secretory activity of parietal cells in vivo, the normal development and cellular homeostasis of the gastric mucosa, and attainment of the normal structure of the secretory membranes. Chronic achlorhydria and hypergastrinemia in aged Atp4a-/- mice produced progressive hyperplasia and mucolytic and IM, and activated the Warburg effect via PI3K/AKT/mTOR signaling.

Weipiling ameliorates gastric precancerous lesions in Atp4a-/- mice.

BACKGROUND: Altered cellular metabolism is considered to be one of the hallmarks of cancer (Coller, Am J Pathol 184:4-17, 2014; Kim and Bae, Curr Opin Hematol 25:52-59, 2018). However, few studies have investigated the role of metabolism in the development of gastric precancerous lesions (GPLs). Weipiling (WPL), a traditional Chinese medicine formula for treatment of GPLs. In this study, we evaluated the amelioration of GPLs by WPL and investigated the possible role of WPL in regulating glucose metabolism. METHODS: Firstly, the major components of WPL are chemically characterized by HPLC analytical method. In this study, we chose the Atp4a-/- mouse model (Spicer etal., J Biol Chem 275:21555-21565, 2000) for GPL analysis. Different doses of WPL were administered orally to mice for 10 weeks. Next, the pathological changes of gastric mucosa were assessed by the H&E staining and AB-PAS staining. In addition, TUNEL staining was used to evaluate apoptosis, and we further used immunohistochemically labelled CDX2, MUC2, ki-67, PTEN, and p53 proteins to assess the characteristic changes of gastric mucosa in precancerous lesions. The levels of such transporters as HK-II, PKM2, ENO1, MPC1, and LDHA were determined by Western blot analysis. Finally, we assessed the expression of mTOR, HIF-1α, AMPK, Rheb, TSC1 and TSC2 protein in the gastric mucosa of Atp4a-/-mice. RESULTS: In this work, we evaluated the protective effect of WPL on gastric mucosa in mice with precancerous lesions. The aberrant apoptosis in gastric mucosa of gastric pre-cancerous lesions was controlled by WPL (P<0.05). Furthermore, WPL suppressed the expression of CDX2, MUC2, ki-67, PTEN and p53, as the levels of these proteins decreased significantly compared with the model group (P<0.05). In parallel, WPL significantly suppressed the expression of transporters, such as HK-II, PKM2, ENO1, MPC1 and LDHA (P<0.05). In addition, mTOR, HIF-1a, AMPK, Rheb, TSC1 and TSC2 protein levels in gastric mucosa of Atp4a-/- mice in the high- and low-dose WPL groups were significantly lower than those in the model group (P<0.05), while the expression of TSC1 and TSC2 protein was significantly higher (P<0.05). CONCLUSIONS: Conclusively, WPL could ameliorate GPLs in Atp4a-/- mice by inhibiting the expression of transporters and suppressing the aberrant activation of mTOR/HIF-1α.

Point application with Angong Niuhuang sticker protects hippocampal and cortical neurons in rats with cerebral ischemia.

Angong Niuhuang pill, a Chinese materia medica preparation, can improve neurological functions after acute ischemic stroke. Because of its inconvenient application and toxic components (Cinnabaris and Realgar), we used transdermal enhancers to deliver Angong Niuhuang pill by modern technology, which expanded the safe dose range and clinical indications. In this study, Angong Niuhuang stickers administered at different point application doses (1.35, 2.7, and 5.4 g/kg) were administered to the Dazhui (DU14), Qihai (RN6) and Mingmen (DU4) of rats with chronic cerebral ischemia, for 4 weeks. The Morris water maze was used to determine the learning and memory ability of rats. Hematoxylin-eosin staining and Nissl staining were used to observe neuronal damage of the cortex and hippocampal CA1 region in rats with chronic cerebral ischemia. The middle- and high-dose point application of Angong Niuhuang stickers attenuated neuronal damage in the cortex and hippocampal CA1 region, and improved the memory of rats with chronic cerebral ischemia with an efficacy similar to interventions by electroacupuncture at Dazhui (DU14), Qihai (RN6) and Mingmen (DU4). Our experimental findings indicate that point application with Angong Niuhuang stickers can improve cognitive function after chronic cerebral ischemia in rats and is neuroprotective with an equivalent efficacy to acupuncture.

[Effect of curcumin on radiosensitization of CNE-2 cells and its mechanism].

OBJECTIVE: To investigate the effect of curcumin (Cur) on radiosensitivity of nasopharyngeal carcinoma cell CNE-2 and its mechanism. METHOD: The effect of curcumin on radiosensitivity was determined by the clone formation assay. The cell survival curve was fitted by Graph prism 6. 0. The changes in cell cycle were analyzed by flow cytometry (FCM). The differential expression of long non-coding RNA was detected by gene chip technology. Part of differentially expressed genes was verified by Real-time PCR. RESULT: After 10 micro mol L-1 Cur had worked for 24 h, its sensitization enhancement ratio was 1. 03, indicating that low concentration of curcumin could increase the radiosensitivity of nasopharyngeal carcinoma cells; FCM displayed a significant increase of G2 phase cells and significant decrease of S phase cells in the Cur combined radiation group. In the Cur group, the GUCY2GP, H2BFXP, LINC00623 IncRNA were significantly up-regulated and ZRANB2-AS2 LOC100506835, FLJ36000 IncRNA were significantly down-regulated. CONCLUSION: Cur has radiosensitizing effect on human nasopharyngeal carcinoma CNE-2 cells. Its mechanism may be related to the changes in the cell cycle distribution and the expression of long non-coding IncRNA.

Xiao Yao San Improves Depressive-Like Behaviors in Rats with Chronic Immobilization Stress through Modulation of Locus Coeruleus-Norepinephrine System.

Most research focuses on the hypothalamic-pituitary-adrenal (HPA) axis, hypothalamus-pituitary-thyroid (HPT) axis, and hypothalamus-pituitary-gonadal (HPGA) axis systems of abnormalities of emotions and behaviors induced by stress, while no studies of Chinese herbal medicine such as Xiao Yao San (XYS) on the mechanisms of locus coeruleus-norepinephrine (LC-NE) system have been reported. Therefore, experiments were carried out to observe mechanism of LC-NE system in response to chronic immobilization stress (CIS) and explore the antidepressant effect of XYS. Rat model was established by CIS. LC morphology in rat was conducted. The serum norepinephrine (NE) concentrations and NE biosynthesis such as tyrosine hydroxylase (TH), dopamine-ß-hydroxylase (DBH), and corticotrophin-releasing-factor (CRF) in LC were determined. Results showed that there were no discernible alterations in LC in rats. The serum NE concentrations, positive neurons, mean optical density (MOD), and protein levels of TH, DBH, and CRF in model group were significantly increased compared to the control group. But XYS-treated group displayed a significantly decreased in NE levels and expressions of TH, DBH, and CRF compared to the model group. In conclusion, CIS can activate LC-NE system to release NE and then result in a significant decrease in rats. XYS treatment can effectively improve depressive-like behaviors in rats through inhibition of LC-NE neurons activity.