Fucoxanthin regulates Nrf2/Keap1 signaling to alleviate myocardial hypertrophy in diabetic rats / 南方医科大学学报

OBJECTIVE@#To investigate the protective effect of fucoxanthin (FX) against diabetic cardiomyopathy and explore the underlying mechanism.@*METHODS@#Rat models of diabetes mellitus (DM) induced by intraperitoneal injection of streptozotocin (60 mg/kg) were randomized into DM model group, fucoxanthin treatment (DM+FX) group and metformin treatment (DM+ Met) group, and normal rats with normal feeding served as the control group. In the two treatment groups, fucoxanthin and metformin were administered after modeling by gavage at the daily dose of 200 mg/kg and 230 mg/kg, respectively for 12 weeks, and the rats in the DM model group were given saline only. HE staining was used to examine the area of cardiac myocyte hypertrophy in each group. The expression levels of fibrotic proteins TGF-β1 and FN proteins in rat hearts were detected with Western blotting. In the cell experiment, the effect of 1 μmol/L FX on H9C2 cell hypertrophy induced by exposure to high glucose (HG, 45 mmol/L) was evaluated using FITC-labeled phalloidin. The mRNA expression levels of the hypertrophic factors ANP, BNP and β-MHC in H9C2 cells were detected using qRT-PCR. The protein expressions of Nrf2, Keap1, HO-1 and SOD1 proteins in rat heart tissues and H9C2 cells were determined using Western blotting. The DCFH-DA probe was used to detect the intracellular production of reactive oxygen species (ROS).@*RESULTS@#In the diabetic rats, fucoxanthin treatment obviously alleviated cardiomyocyte hypertrophy and myocardial fibrosis, increased the protein expressions of Nrf2 and HO-1, and decreased the protein expressions of Keap1 in the heart tissue (P < 0.05). In H9C2 cells with HG exposure, fucoxanthin significantly inhibited the enlargement of cell surface area, lowered the mRNA expression levels of ANP, BNP and β-MHC (P < 0.05), promoted Nrf2 translocation from the cytoplasm to the nucleus, and up-regulated the protein expressions its downstream targets SOD1 and HO-1 (P < 0.05) to enhance cellular antioxidant capacity and reduce intracellular ROS production.@*CONCLUSION@#Fucoxanthin possesses strong inhibitory activities against diabetic cardiomyocyte hypertrophy and myocardial fibrosis and is capable of up-regulating Nrf2 signaling to promote the expression of its downstream antioxidant proteins SOD1 and HO-1 to reduce the level of ROS.

Mosquito coil exposure associated with small cell lung cancer: A report of three cases.

Mosquito coils, which are commonly used as residential insecticides in Asia, contain different concentrations of octachlorodipropyl ether (S-2) as a synergist or an active ingredient. As bis(chloromethyl) ether (BCME) is an extremely potent lung carcinogen that can be produced by the thermolytic degradation of S-2, contact with mosquito coils is likely to expose individuals to a certain level of BCME, and therefore increase the risk of lung cancer. However, the significance of exposure is uncertain, as clinical and epidemiological studies concerning mosquito coil users and workers are lacking. The present study describes three cases of small cell lung cancer treated at the Shanghai Pulmonary Hospital that were likely to be the result of exposure to mosquito coils. All patients had worked in the mosquito coil manufacturing industry, with an mean occupational duration of 9.1 years, and presented with similar respiratory symptoms, such as cough and dyspnea. Upon diagnosis, no metastasis to other organs was identified in any of the cases. Subsequently, the three patients were treated with chemotherapy as well as radiotherapy in one case, however, all patients succumbed to the disease, with a mean overall survival time of 10.7 months. We conclude that contact with mosquito coils is likely to expose individuals to a level of S-2 that may increase the risk of SCLC.

Efficacy of pemetrexed in a patient with brain metastases during crizotinib treatment.

ALK-positive patients with non-small-cell lung cancer (NSCLC) exhibit more aggressive clinical progression, a poorer response to chemotherapy, and less favorable survival outcomes in comparison with ALK-negative patients. Although crizotinib has proved effective in treating ALK-positive NSCLC, this agent penetrates the blood-brain barrier poorly and CNS progression is common. As pemetrexed, a multitargeted antifolate chemotherapeutic agent, has demonstrated benefit in the control of brain metastases in patients with NSCLC, treatment with pemetrexed was added to crizotinib in a young male patient with ALK-positive NSCLC who had developed brain metastases during crizotinib therapy. After four cycles of pemetrexed chemotherapy, the patient's brain lesions were significantly reduced in size and a chest CT scan showed that the lung lesions had stabilized.

Etoposide-cisplatin alternating with vinorelbine-cisplatin versus etoposide-cisplatin alone in patients with extensive disease combined with small cell lung cancer.

BACKGROUND: The aim of this study was to evaluate the efficacy of alternating etoposide-cisplatin and vinorelbine-cisplatin (EP-NP) compared with an etoposide-cisplatin (EP) regimen for advanced combined small cell carcinomas. MATERIALS AND METHODS: Histologically confirmed combined small cell carcinoma patients who met the inclusion criteria were randomly assigned (1:1) into either the EP-NP setting (group A) or the EP setting (group B). The primary endpoint was progression-free survival in patients who received at least one dose of treatment. RESULTS: Eighty-two patients entered into this trial, 42 in group A and 40 in group B. The objective response rates in group A and group B were 42.9% and 32.5%, respectively (p=0.334). Survival analysis showed that median progression-free survival was 6.1 months in group A, which was significantly longer than the 4.1 months in group B (p=0.041). However, as to overall survival, no significant difference was found between the two groups (11.0 vs 10.1 months in groups A and B, respectively, p=0.545). No unexpected side effects were observed in either group. CONCLUSIONS: The EP-NP regimen for combined small cell carcinomas prolonged progression- free survival compared with the EP regimen. Further clinical investigations are warranted.

Epithelial-to-mesenchymal transition markers to predict response of Berberine in suppressing lung cancer invasion and metastasis.

BACKGROUND: The effects of berberine on the metastatic potential of lung cancer cells and its underlying mechanisms have not been fully elucidated. Since epithelial-to-mesenchymal transition is a cellular process associated with cancer invasion and metastasis, we attempted to investigate the potential use of berberine as an inhibitor of TGF-ß1-induced epithelial-to-mesenchymal in A549 cells. METHODS: In this study, we investigated the anticancer activity of berberine against A549 cells in vitro and in vivo. BBR-induced apoptosis of the human lung cancer cells was determined by flow cytometry. The ability of BBR to inhibit TGF-ß-induced EMT was examined by QRT-PCR and Western blotting. The impact of BBR on A549 cell migration and invasion was evaluated by transwell assay. RESULTS: We demonstrated that TGF-ß1 induced epithelial-to-mesenchymal to promote lung cancer invasion and metastasis. Berberine inhibited invasion and migration of A549 cells, increased expression of the epithelial phenotype marker E-cadherin, repressed the expression of the mesenchymal phenotype marker Vimentin, as well as decreased the level of epithelial-to-mesenchymal -inducing transcription factors Snail1 and Slug during the initiation of TGF-ß1-induced epithelial-to-mesenchymal. Furthermore, berberine inhibited growth of lung cancer cells in vivo xenograft. CONCLUSIONS: Our findings provided new evidence that berberine is an effective inhibitor of the metastatic potential of A549 cells through suppression of TGF-ß1-induced epithelial-to-mesenchymal.

Combined inhibition of insulin-like growth factor-1 receptor enhances the effects of gefitinib in a human non-small cell lung cancer resistant cell line.

The type I insulin-like growth factor receptor (IGF-1R) signaling pathway is an important growth-regulatory pathway that is prevalent in a variety of cancer types, including human non-small cell lung cancer (NSCLC). To observe the combined effects of gefitinib and AG1024-induced IGF-1R inhibition on the growth of NSCLC, PC9/G cells, a NSCLC cell line with acquired resistance to gefitinib, were treated with AG1024 and gefitinib, alone or in combination. The proliferative activity of PC9/G cells upon different treatments was assessed by CCK-8, and the median-effects principle was used to assess the effect of the combined treatment. Apoptotic rates of the PC9/G cells for the different treatment groups were analyzed by flow cytometry. The expression of phosphorylated epidermal growth factor receptor (p-EGFR), phosphorylated-Akt (p-Akt), and phosphorylated extracellular signal-regulated kinase (p-ERK) in PC9/G cells was examined by Western blotting. PC9/G cells exhibited apoptotic features after treatment with AG1024 and gefitinib alone, and their proliferation rates were inhibited to different degrees. The treatment of AG1024 combined with gefitinib resulted in a synergistic effect in inducing apoptosis, inhibiting cell proliferation and decreasing the expression of p-EGFR, p-Akt and p-ERK. In conclusion, combined inhibition of IGF-1R signaling enhances the anti-proliferative and pro-apoptotic effects of gefitinib in NSCLC gefinitib-resistant cells. Moreover, the addition of an anti-IGF-1R strategy to gefitinib treatment may be more effective than a single-agent approach.