Luteolin inhibits the TGF-ß signaling pathway to overcome bortezomib resistance in multiple myeloma.

Multiple myeloma (MM) is an incurable condition and the second most common hematological malignancy. Over the past few years, there has been progress in the treatment of MM, but most patients still relapse. Multiple myeloma stem-like cells (MMSCs) are believed to be the main reason for drug resistance and eventual relapse. Currently, there are not enough therapeutic agents that have been identified for eradication of MMSCs, and thus, identification of the same may alleviate the issue of relapse in patients. In the present study, we showed that luteolin (LUT), a natural compound obtained from different plants, such as vegetables, medicinal herbs, and fruits, effectively inhibits the proliferation of MM cells and overcomes bortezomib (BTZ) resistance in them in vitro and in vivo, mainly by decreasing the proportion of ALDH1+ cells. Furthermore, RNA sequencing after LUT treatment of MM cell lines and an MM xenograft mouse model revealed that the effects of the compound are mediated through inhibition of transforming growth factor-ß signaling. Similarly, we found that LUT also significantly reduced the proportion of ALDH1+ cells in primary CD138+ plasma cells. In addition, LUT could overcome the BTZ treatment-induced increase in the proportion of ALDH1+ cells, and the combination of LUT and BTZ had a synergistic effect against myeloma cells. Collectively, our findings suggested that LUT is a promising agent that manifests MMSCs to overcome BTZ resistance, alone or in combination with BTZ, and thus, is a potential therapeutic drug for the treatment of MM.

[Electroacupuncture promotes gastrointestinal motility by activating autophagy of Cajal interstitial cells via downregulating PI3K/Akt/mTOR signaling pathway in stomach of diabetic gastro-paresis rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Zusanli" (ST36), "Sanyinjiao" (SP6) and "Liangmen" (ST21) on gastrointestinal motility, blood glucose content and expression of autophagy-related proteins 1 light chain 3 (LC3), p62, phosphatidyli-nositol-3 kinase (PI3K), protein kinase B (Akt), p-Akt and mammalian target protein of rapamycin (mTOR) of interstitial cells of Cajal (ICCs) in the cultured gastric antrum cells in diabetic gastroparesis (DGP) rats, so as to reveal its mechanisms underlying improvement of DGP. METHODS: A total of 45 Sprague Dawley (SD) rats were randomly divided into blank control, model, EA, medication (3-methyladenine, 3-MA) and EA+3-MA groups, with 9 rats in each group. The DGP model was established by intraperitoneal injection of 2% streptozotocin (STZ) combined with high-fat and high sugar diet for 8 weeks. The gastric emptying rate was measured by using gavage of phenol red (to measure the propelling length of the phenol red/total length of small intestine ×100%). The symptom score (mental state, coat color and luster, behavior and activity, stool traits) of rats was observed every week and the blood glucose content was measured by using a glucometer. EA (20 Hz/100 Hz, 2 mA) was applied to unilateral ST36, SP6 and ST21 alternatively for 15 min, once daily, 5 days a week for 3 weeks. Rats of the 3-MA and 3-MA+EA groups received intraperitoneal injection of 3-MA (30 mg·kg-1·d-1, 10 mg/mL), once daily, 5 days a week for 3 weeks. After 15 days' intervention, the rats were operated for gastric emptying rate test, specimen collection, isolation, and culture of primary ICCs. The expression levels of microtubule associated protein LC3, p62, PI3K, Akt, p-Akt and mTOR of ICCs of cultured gastric antrum cells were detected using Western blot, and the number of autophagosomes in ICC of gastric antrum was observed under transmission electron microscope. RESULTS: Compared with the blank control group, the symptom score, blood glucose, and the expression levels of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins were increased significantly (P<0.01), while the gastric emptying rate and ratio of LC3Ⅱ/LC3Ⅰ and the expression level of class Ⅲ PI3K protein were significantly decreased (P<0.05, P<0.01) in the model group. In comparison with the model group, the increase of symptom score, blood glucose, and expression levels of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins and the decrease of gastric empty rate and LC3Ⅱ/LC3Ⅰ ratio and the expression level of class Ⅲ PI3K protein were all reversed in both EA and EA+3-MA groups (P<0.05, P<0.01), rather than in the 3-MA group. In addition, 3-MA also reversed modeling-induced increase of class Ⅰ PI3K, Akt, p-Akt and mTOR proteins expression (P<0.01). No significant differences were found between the EA and EA+3-MA in downregulating the levels of symptom score and blood glucose content, and in upregulating gastric empty rate(P>0.05). The effect of EA was notably superior to that of EA+3-MA in upregulating the ratio of LC3Ⅱ/LC3Ⅰ and the expression level of class Ⅲ PI3K protein, and in downregulating the expression of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins (P<0.05, P<0.01). The findings of transmission electron microscopy showed obvious swelling, breakage of some mitochondrial cristae in the ICC cells of antrum and no autophagosomes in the model group and 3-MA group, which was milder in the damage of mitochondrial cristae and marked increase in the autophagosomes in both EA and EA+3-MA groups. CONCLUSION: EA can improve the gastrointestinal motility and symptoms in DGP rats, which may be related to its functions in downregulating PI3K/Akt/mTOR signaling to promote autophagy level of ICC.

Curcumol and FTY720 synergistically induce apoptosis and differentiation in chronic myelomonocytic leukemia via multiple signaling pathways.

Chronic myelomonocytic leukemia (CML) is a myeloid tumor characterized by MDS (myelodysplastic syndrome) and MPN (myeloproliferative neoplasms). Allogeneic hematopoietic stem cell transplantation, chemotherapy, interferon, and targeted therapy are the main treatment methods for CML. Tyrosine kinase inhibitors (TKIs) are also a treatment option, and patients are currently recommended to take these drugs throughout their lives to prevent CML recurrence. Therefore, there is a need to investigate and identify other potential chemotherapy drugs. Currently, research on CML treatment with a single drug has shown little progress. Fingolimod (FTY720), an FDA-approved drug used to treat relapsing multiple sclerosis, has also shown great potential in the treatment of lymphocytic leukemia. In our study, we find that FTY720 and curcumol have a significant inhibitory effect on K562 cells, K562/ADR cells, and CD34+ cells from CML patients. RNAseq data analysis shows that regulation of apoptosis and differentiation pathways are key pathways in this process. Besides, BCR/ABL-Jak2/STAT3 signaling, PI3K/Akt-Jnk signaling, and activation of BH3-only genes are involved in CML inhibition. In a K562 xenograft mouse model, therapy with curcumol and FTY720 led to significant inhibition of tumor growth and induction of apoptosis. To summarize, curcumol and FTY720 synergistically inhibit proliferation involved in differentiation and induce apoptosis in CML cells. Therefore, synergistic treatment with two drugs could be the next choice of treatment for CML.

Electroacupuncture Relieves Suppression of Autophagy in Interstitial Cells of Cajal of Diabetic Gastroparesis Rats.

Background: The incidence of diabetic gastroparesis (DGP) is mainly blamed to abnormity of interstitial cells of Cajal (ICCs). Autophagy could degrade damaged proteins and organelles to keep intracellular homeostasis, and it could directly influence structure and number of cells. In this study, we aimed to figure out the relationship between DGP and autophagy of ICCs. Methods: Sixty Sprague-Dawley (SD) rats were randomly divided into normal control group (NC, 10) and modeling group (50). Rats in the modeling group were injected 2% streptozotocin (STZ) and fed with high-glucose and high-fat diet for 8 weeks in order to establish DGP rat model. After modeling, 30 successfully modeled rats were randomly selected and separated into diabetic gastroparesis group (DGP, 10), GDP rats with electroacupuncture group (EA, 10), and GDP rats with metoclopramide group (MP, 10). When the intervention was completed, blood glucose was measured by ONE TOUCH glucometer and gastrointestinal propulsive rate was detected through measuring optical density. Autophagosomes were observed under transmission electron microscope (TEM). The expression of LC3 protein and P62 protein was measured by Western blot. When ICCs were transfected with GFP-RFP-LC3 plasmid, autophagy flux was observed by laser scanning confocal microscope. Results: (1) After intervention, compared with blood glucose of rats in the NC group, all of the DGP, EA, and MP groups were remarkably increased (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01); compared with the DGP group, the blood glucose of the EA and MP groups was decreased greatly (P < 0.01). (2) Compared with gastrointestinal propulsive rate of rats in the NC group, no matter gastric emptying rate or intestinal propulsive rate, the EA and MP groups were significantly reduced (P < 0.01); compared with the NC group, gastric emptying rate and intestinal propulsive rate in the EA group were obviously decreased (P < 0.05, P < 0.01); compared with the DGP group, the EA and MP groups were increased significantly (P < 0.01). (3) Compared with the NC group, intensity of RFP and GFP in the DGP group was obviously increased (P < 0.05, P < 0.01), in other words, the DGP group accompanying suppression of autophagy; compared with the DGP group, intensity of RFP and GFP in the EA group was decreased significantly (P < 0.05, P < 0.01). (4) There was no autophagosome in the NC group, and an autophagosome existed in the DGP group. Both EA and MP groups found autophagy. (5) When coming to LC3 II/LC3 I, compared with the NC group, the ratio was enhanced in the DGP and EA groups (P < 0.01, P < 0.05); compared with the DGP group, LC3 II/LC3 I was dramatically decreased in the MP and EA groups (P < 0.01). (6) As the substrate of degradation, the expression of P62 in the other three groups was significantly increased (P < 0.01) compared with the NC group; compared with the DGP group, the amount of P62 in the EA and MP groups was reduced greatly (P < 0.01). Conclusion: The impaired autophagy flux in ICCs is the pathological basis of diabetic gastroparesis, blaming to fusion dysfunction of autophagosome and lysosome and electroacupuncture (EA) could ease the suppression of autophagy to improve gastric motility.

Effects and molecular mechanisms of Ninghong black tea extract in nonalcoholic fatty liver disease of rats.

The aim of this study is to observe the effects of Ninghong black tea extract on fat deposition and high-fat diet-induced nonalcoholic fatty liver disease (NAFLD) and to explore the potential mechanisms of these effect. Under 2% Ninghong black tea extract diet feeding in rat model, the results showed that Ninghong black tea extract decreased the body fat ratio and the number of lipid droplets in the liver and significantly alleviated NAFLD in the rat model. The real-time fluorescence quantitative polymerase chain reaction results showed that Ninghong black tea extract significantly upregulated the expression of peroxisome proliferator-activated receptor α (PPARα), which is important in fatty acid ß-oxidation, and microsomal triglyceride transfer protein (MTP), which plays an important role in the synthesis of very low density lipoprotein (VLDL). By promoting the expression of PPARα and MTP in liver tissue and thereby promoting fatty acid ß-oxidation and VLDL synthesis, Ninghong black tea extract relieves high-fat diet-induced NAFLD.