Autophagy as a novel insight into mechanism of Danqi pill against post-acute myocardial infarction heart failure.

ETHNOPHARMACOLOGICAL RELEVANCE: Danqi Pill, composed of the root of Salvia miltiorrhiza Bunge and the root of Panax notoginseng, is effective in the clinical treatment of myocardial ischemia in coronary heart diseases. A number of studies have shown that autophagy plays an essential role in cardiac function and energy metabolism, and disordered autophagy is associated with the progression of heart failure. However, the effect and mechanism of Danqi pill on autophagy have not been reported yet. AIM OF THE STUDY: This study aims to elucidate whether Danqi pill restores autophagy to protect against HF and its potential mechanism. MATERIALS AND METHODS: Left anterior descending ligation was established to induce an HF rat model, H2O2-stimulated H9C2 cells model was conducted to clarify the effects and potential mechanism of Danqi pill. In vivo, Danqi pill (1.5 g/kg) were orally administered for four weeks and Fenofibrate (10 mg/kg) was selected as a positive group. In vitro, Danqi pill (10-200 µg/mL) was pre-cultured for 24 h and co-cultured with H2O2 stimulation for 4 h. Importantly, transmission electron microscopy and fluorescence GPF-mRFP-LC3 reporter system were combined to monitor autophagy flux. Furtherly, we utilized Compound C, a specific AMPK inhibitor, to validate whether the autophagy was mediated by AMPK-TSC2-mTOR pathway. RESULTS: Danqi pill significantly improved cardiac function and myocardial injury in HF rats. Intriguingly, Danqi pill potently regulated autophagy mainly by promoting the formation of autophagosomes in vivo. Further results demonstrated that expressions of p-AMPK (P < 0.001) and p-TSC2 (P < 0.001) in cardiac tissue were upregulated by Danqi pill, accompanied with downregulation of p-mTOR (P < 0.01) and p-ULK1(P < 0.01). In parallel with the vivo experiment, in vitro study indicated that Danqi pill dramatically restored autophagy flux and regulated expressions of critical autophagy-related molecules. Finally, utilization of Compound C abrogated the effects of Danqi pill on autophagy flux and the expressions of p-TSC2 (P < 0.05), p-mTOR (P < 0.01) and p-ULK1 (P < 0.05). CONCLUSION: Danqi pill could improve cardiac function and protect against cardiomyocytes injury by restoring autophagy via regulating the AMPK-TSC2-mTOR signaling pathway.

Pharmacoproteomics reveals the mechanism of Chinese dragon's blood in regulating the RSK/TSC2/mTOR/ribosome pathway in alleviation of DSS-induced acute ulcerative colitis.

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese dragon's blood (CDB), a crude drug extracted from Dracaena cochinchinensis (Lour.) S.C. Chen, has been historically applied for the treatment of various diseases, including ulcerative colitis (UC). Unfortunately, the underlying molecular mechanism remains unclear. MATERIALS AND METHODS: In this paper, the effects of CDB treatment on a mouse model of acute UC and proteomic variation in colonic tissue were investigated. The acute UC model in Balb/c mice was induced by administration of 2.5% (wt/vol) dextran sulfate sodium (DSS) in drinking water for 8 days. After the mice with UC were intragastrically administered CDB and intraperitoneally injected with rapamycin (RAPA, a specific inhibitor of mTORC1), the disease activity index (DAI) and histopathological score were recorded. An isobaric tags for relative and absolute quantification (iTRAQ) based LC-MS/MS proteomic technique was adopted to identify the differentially expressed proteins (DEPs) in colonic tissue. Bioinformatics analysis was used to discover the molecular functions and pathways of the DEPs. Finally, Western blot analysis and immunohistochemistry were used to verify the protein expression. RESULTS: The results showed that CDB treatment significantly ameliorated the symptoms and intestinal damage in acute UC, while RAPA treatment led to severe symptoms and intestinal damage. A total of 489 DEPs were reversed in the control check (CK) group and the CDB group. Most DEPs were enriched in the structural constituents of ribosomes and the ribosome pathway. CDB treatment significantly upregulated the expression of the mTOR, p-mTOR and p70S6K proteins and downregulated the expression of the Akt, p-Akt, and p4EBP1 proteins. However, RAPA treatment, unlike CDB, did not return the levels of mTOR, Akt, and their phosphorylated forms to nearly normal. CONCLUSIONS: In conclusion, the dysfunction of the mTOR/ribosome pathway resulting in the inhibition of ribosome synthesis played an important role in the development of acute UC in mice, and CDB, but not RAPA, was an alternative drug for the treatment of acute UC by enhancing ribosome synthesis via the mTOR/ribosome pathway and further promoting protein synthesis.

Electroacupuncture Upregulated Ghrelin in Rats with Functional Dyspepsia via AMPK/TSC2/Rheb-Mediated mTOR Inhibition.

BACKGROUND: Gastrointestinal motility disorder is an important pathological basis for functional dyspepsia (FD). Epigastric ache and discomfort are the main symptoms of FD, and ghrelin deficiency is closely related to the occurrence and development of FD. While electroacupuncture (EA) alleviated the symptoms of FD patients and improved their quality of life, there is a lack of sufficient mechanistic evidence to support these beneficial effects. METHODS: An in vivo FD model was established in wild-type and mammalian target of rapamycin (mTOR) knockout (-/-) rats. FD rats were subjected to EA with or without mTOR agonists or inhibitors. Gastric emptying and intestinal propulsion were assessed, and pathological changes in the hypothalamus, gastric antrum, and small intestine were examined histologically. In addition, ghrelin expression and AMPK/TSC2/Rheb/mTOR activation were detected by quantitative reverse transcription polymerase chain reaction and western blot. RESULTS: EA alone or in combination with mTOR inhibitors improved gastrointestinal function in FD rats by increasing the rates of intestinal propulsion and gastric emptying, and pathological changes in the hypothalamus, gastric antrum, and small intestine were alleviated. This may be related to the significant upregulation of ghrelin expression and the effective activation of the AMPK/TSC2/Rheb/mTOR signaling pathway. Interestingly, EA also improved gastrointestinal function and ghrelin expression in mTOR (-/-) KO FD rats. CONCLUSION: Altering the level of ghrelin by regulating AMPK/TSC2/Rheb-mediated mTOR inhibition is an important way through which EA treats FD. The complex EA-mediated regulatory mechanisms of the brain-gut axis still require further exploration.

[Ginsenoside Rg_1 induces leukemia stem cell senescence via SIRT1/TSC_2 signal axis].

The aim of this paper was to investigate the effect of SIRT1/TSC_2 signal axis on leukemia stem cell senescence induced by ginsenoside Rg_1. CD34~+CD38~- leukemia stem cells(CD34~+CD38~-LSCs) was isolated by magnetic cell sorting(MACS) and divided into two groups. The control group cells were routinely cultured, 40 µmol·L~(-1) ginsenoside Rg_1 was added to the control group for co-culture in Rg_1 group. The effect of Rg_l to induce CD34~+CD38~-LSCs senescence were evaluated by senescence-associated ß-Galactosidase(SA-ß-Gal) staining, cell cycle assay, CCK-8 and Colony-Assay. The expression of senescence associated SIRT1, TSC_2 mRNA and protein was examined by Real-time fluorescence quantitative PCR(FQ-PCR) and Western blot. The results showed that the CD34~+CD38~-LSCs could effectively be isolated by MACS, and the purity of CD34~+CD38~-LSCs is up to(95.86±3.04)%. Compared with the control group, the percentage of positive cells expressed SA-ß-Gal in the Rg_1 group is increased, the senescence morphological changes were observed in the CD34~+CD38~-LSCs in the Rg_1 group. The proliferation inhibition rate and the number of cells entered G_0/G_1 phase in the Rg_1 group were increased, but the colony-formed ability was decreased, Rg_1 could significantly inhibit the proliferation and self-renewal ability of CD34~+CD38~-LSCs. The expression of SIRT1 and TSC_2 mRNA and protein were down regulated in the Rg_1 group compared with the control group. Our research implied that Rg_1 may induce the senescence of CD34~+CD38~-LSCs and SIRT1/TSC_2 signal axis plays a significant role in this process.

Potential therapeutic effect of curcumin, a natural mTOR inhibitor, in tuberous sclerosis complex.

BACKGROUND: Curcumin is a polyphenol natural product of the plant Curcuma longa. Recent studies suggest that curcumin inhibit mTOR activity in vitro, which prompts us to investigate curcumin function as a new class of mTOR inhibitor suitable for tuberous sclerosis complex (TSC) treatment. PURPOSE: We aim to investigate the efficacy of curcumin in the treatment of TSC related manifestations in animal model. STUDY DESIGN: Solid lipid curcumin particle (SLCP), a novel curcumin formulation, was used to treat TSC related manifestations in Tsc2 knockout mice. METHODS: The novel object recognition test was used to analyze the recognition memory function. The long-term potentiation was studied using electrophysiological analysis. Western blotting was used to assess the protein expression and activation status. RESULTS: Recognition memory deficit began as early as 4 weeks of age in both male and female Tsc2+/- mice. Oral administration with SLCP activates AMPK activity and inhibits mTOR activity in the brain tissue of Tsc2+/- mice, and can rescue the electrophysiological abnormality and object recognition memory loss in the mice. CONCLUSIONS: Our results suggest that SLCP could be an effective treatment for TSC patients.

Rationally Designed 3D Hydrogels Model Invasive Lung Diseases Enabling High-Content Drug Screening.

Cell behavior is highly dependent upon microenvironment. Thus, to identify drugs targeting metastatic cancer, screens need to be performed in tissue mimetic substrates that allow cell invasion and matrix remodeling. A novel biomimetic 3D hydrogel platform that enables quantitative analysis of cell invasion and viability at the individual cell level is developed using automated data acquisition methods with an invasive lung disease (lymphangioleiomyomatosis, LAM) characterized by hyperactive mammalian target of rapamycin complex 1 (mTORC1) signaling as a model. To test the lung-mimetic hydrogel platform, a kinase inhibitor screen is performed using tuberous sclerosis complex 2 (TSC2) hypomorphic cells, identifying Cdk2 inhibition as a putative LAM therapeutic. The 3D hydrogels mimic the native niche, enable multiple modes of invasion, and delineate phenotypic differences between healthy and diseased cells, all of which are critical to effective drug screens of highly invasive diseases including lung cancer.