Anticoagulant management by low-dose of low molecular weight heparin in patients with nonvalvular atrial fibrillation following hemorrhagic transformation and complicated with venous thrombosis: Five case reports and literature review.

ABSTRACT: For patients with nonvalvular atrial fibrillation (NVAF) following hemorrhagic infarction (HI)/hemorrhage transformation (HT) and complicated with venous thrombosis, the management of anticoagulation is controversial. Our study intends to explore the safety and effectiveness of using low-dose of low molecular weight heparin (LMWH) to treat NVAF patients with HI (or HT) and complicated with venous thrombosis.Between January 2018 and January 2019, NVAF related acute ischemic stroke patients with HT/HI, hospitalized in the department of neurology or rehabilitation in our hospital, are enrolled retrospectively. Among them, those who were found to have venous thrombosis and undergo anticoagulation (LMWH) during the treatment were extracted. We investigate the efficacy and safety in those patients who have been treated with anticoagulant of LMWH.Five cases accepted LMWH within 3 weeks attributed to the appearance of venous thrombosis, and all of them did not display new symptomatic bleeding or recurrent stroke. However, based on the results of a head computed tomography scan, there were 2 cases of slightly increased intracranial hemorrhage, and then we reduced the dose of anticoagulant. In addition, color ultrasound showed that venous thrombosis disappeared or became stable.Patients with NVAF following HI/HT have a higher risk of thromboembolism. Early acceptance of low-dose LMWH as an anticoagulant is relatively safe and may gain benefit. However, in the process of anticoagulant therapy, we should follow-up head computed tomography/magnetic resonance imaging frequently, as well as D-dimer values, limb vascular ultrasound. Besides, the changes of symptoms and signs should be focused to judge the symptomatic bleeding or recurrent stroke. Furthermore, it is better to adjust anticoagulant drug dosage according to specific conditions.

Photodynamic Therapy Mediated by Aloe-Emodin Inhibited Angiogenesis and Cell Metastasis Through Activating MAPK Signaling Pathway on HUVECs.

Photodynamic therapy is a clinically used, minimally invasive therapeutic procedure that involves the application of photosensitizers which can locate in target cells and so be irradiated at a corresponding wavelength. Laser light irradiation activation of photosensitizers generates free reactive oxygen species, which induces selective cytotoxic activity in target cells. Within recent years, aloe-emodin as a photosensitizer has been successfully applied in photodynamic therapy applications. Angiogenesis plays an important role in tumor growth and metastasis; thus, the development of a novel target treatment for angiogenesis is essential in order to improve treatment therapeutics for cancer treatment. An essential step in angiogenesis involves the formation of tube-like structures during matrix degradation, rearrangement, and apoptosis of endothelial cells. In the present study, we investigated the mechanisms of photocytotoxicity induced by aloe-emodin in human umbilical vein endothelial cells. Analysis of cell proliferation results noted a significant decrease in cultured cells which received various concentrations of aloe-emodin and photodynamic therapy-induced light doses. Additionally, mitochondrial mechanisms of apoptotic cell death were observed in aloe-emodin photodynamic therapy-treated cells, as tube formation assays noted angiogenesis suppression after treatment. The capacity of migration and invasion of human umbilical vein endothelial cells was measured using the transwell assay and demonstrated that aloe-emodin photodynamic therapy significantly inhibited the migration and invasion of human umbilical vein endothelial cells. The expression of p38, extracellular signal-regulated kinase, the c-Jun N-terminal kinases, and vascular endothelial growth factor suggested that the cellular metastasis was related to mitogen-activated protein kinase signal pathway. Furthermore, disorganization of F action cytoskeleton components was observed after aloe-emodin photodynamic therapy. Overall, the findings from this study suggest that aloe-emodin photodynamic therapy inhibited angiogenesis and cellular metastasis in human umbilical vein endothelial cells by activating the mitogen-activated protein kinase apoptotic signaling cell death pathway.

Inhibition of breast cancer cell growth by methyl pyropheophenylchlorin photodynamic therapy is mediated though endoplasmic reticulum stress-induced autophagy in vitro and vivo.

Autophagy and ER stress participated in the inhibition of MPPa-PDT on tumor growth, but the molecular links between them remain undefined. We just explore the molecular mechanism between them in vitro and vivo. CCK-8 assay and flow cytometer were used to detect the cytotoxicity and mode of cell death after MPPa-PDT. Furthermore, the role of autophagy was verified in MPPa-PDT. Confocal microscopy was used to show the intracellular distribution of MPPa. ER stress markers and PERK signaling pathway were detected by western blot. While in vivo, tumor histology and immunohistochemistry were performed to show the effect of MPPa-PDT in mice. After MPPa-PDT, cells viability decreased in dose-dependent manner. Besides, the cell apoptosis increased along with the increasing of Beclin-1and LC3B II but declining of P62. When pretreated with 3-MA, LC3B II formation and the cytotoxicity declined. MPPa-PDT caused increasing of ER stress markers (GRP78, CHOP) as MPPa accumulated in ER. However, pretreatment with ER stress inhibitor 4PBA, the expression of GRP78 and LC3B II was blocked but the PERK signaling pathway activated and the expression of P62 increased. In vivo, the tumor growth was significantly inhibited by MPPa-PDT. Besides, the appearance of ER stress and autophagy was further demonstrated by immunohistochemistry. Our findings demonstrate that autophagy mediated by MPPa-PDT was regulated by ER stress, via PERK signaling pathway, to kill MDA-MB-231 cells in vitro and vivo.

The effect of aloe-emodin-induced photodynamic activity on the apoptosis of human gastric cancer cells: A pilot study.

The aim of the present study was to explore the effect of aloe-emodin (AE)-induced photodynamic activity in human gastric cancer cells. AE was used as a photosensitizer to explore the effect of photodynamic therapy (PDT) in human gastric cancer cells (SGC-7901). An MTT assay was used to detect the effect of AE-induced PDT in optimal concentrations and illumination energy densities in human gastric cancer cells. Following AE-induced PDT, morphological changes of the cells and the rate of cell death were evaluated by TUNEL assay and flow cytometry, respectively. The expression levels of caspase-9 and caspase-3 were determined by western blot analysis. The AE and AE-induced PDT demonstrated a significant inhibitive effect on the proliferation of human gastric cancer cells in dose-dependent and energy-dependent manners. For subsequent experiments, 10 µM AE and 12.8 J/cm2 illumination energy density were used. Typical morphological changes of apoptosis were observed in the cells using a TUNEL assay 12 h subsequent to AE-induced PDT. The percentage of apoptotic cells treated with AE-induced PDT significantly increased when compared with the control group, the 10 µM AE group and the illumination group (P<0.05). Upregulation of caspase-9 and caspase-3 protein levels was also observed following AE-induced PDT. The present study revealed that 10 µM AE-induced PDT had an inhibitory effect on human gastric cancer cells, and it may induce cell apoptosis by upregulating caspase-9 and caspase-3, which indicated that the mitochondrial pathway may be involved. AE-induced PDT has the potential to be a novel therapy for the treatment of human gastric cancer. However, further investigations are required.

Enhancement of the Effect of Methyl Pyropheophorbide-a-Mediated Photodynamic Therapy was Achieved by Increasing ROS through Inhibition of Nrf2-HO-1 or Nrf2-ABCG2 Signaling.

BACKGROUND: Emerging evidence indicates that the transcription factor nuclear factor-E2-related factor 2 (Nrf2) plays an essential role in cellular defense against oxidative stress; its activation has been related to cytoprotection. OBJECTIVE: Here, we investigated the role of Nrf2 in improving the efficacy of methyl pyropheophorbide-amediated photodynamic therapy (Mppa-PDT) via the downregulation of Nrf2. METHOD: Human ovarian cancer A2780 cells and SKOV3 cells were treated with Mppa-PDT and siRNA transfection was performed to inhibit Nrf2. After treated with siRNA and Mppa-PDT, the cell viability was examined with CCK-8 assay; cell apoptosis was detected tested by flow cytometry with Annexin V-FITC/PI; the celluar reactive oxygen species (ROS) and mitochondrial membrane potential were measured with DCFHDA and JC-1 staining; expression of protein was assessed by western blot analysis. RESULTS: We found that Nrf2 translocated from the cytoplasm to the nucleus in vitro and in vivo, and the expression of Nrf2 and P-Nrf2 increased through a possible mechanism regulated by mitogen-activated protein kinase (MAPK) after Mppa-PDT treatment. Furthermore, cytotoxicity and apoptosis induced by Mppa-PDT increased after Nrf2down-regulation. Nrf2 down -regulation increased reactive oxygen species (ROS) levels by attenuating antioxidants or pumping Mppa out of cells,which resulted from the inhibition of Nrf2-HO-1 or Nrf2- ABCG2 signaling. In addition, SKOV3 cells exhibited increased resistance to Mppa-PDT, and the expression levels of P-Nrf2 and ABCG2 were higher in SKOV3 cells than in A2780 cells, suggesting that Nrf2-ABCG2 signaling might be involved in the intrinsic resistanceto Mppa-PDT. CONCLUSION: These results provided evidence that Nrf2 down-regulation can enhance the effect of Mppa-PDT.

Mitochondrial pathway and endoplasmic reticulum stress participate in the photosensitizing effectiveness of AE-PDT in MG63 cells.

Photodynamic therapy (PDT) is a promising treatment in cancer therapy, with a photosensitizer activated by visible light. Aloe-emodin (AE) is a promising photosensitive agent. In this study, the photosensitizing effects and possible mechanisms of AE-PDT in MG63 cells were evaluated. The efficiency of AE-PDT was analyzed by MTT assay. The mode of cell death was investigated by Hoechst 33,342 staining and flow cytometer. The intracellular distribution of AE was detected with confocal microscopy. The formation of reactive oxygen species (ROS) was detected by DCFH-DA. The mitochondrial membrane potential (MMP) was measured by Rhodamine 123. The expression of proteins including cytochrome c, caspase-3, -9, and -12, CHOP and GRP78 was detected by western blot. Apoptosis is the primary mode of cell death in our study, which occurs in a manner of depending on AE concentration and irradiation dose. Confocal microscopy showed that AE was primarily localized on the mitochondria and endoplasmic reticulum (ER) of MG63 cells. AE-PDT resulted in rapid increases of intracellular ROS production, which reached a peak at 2 h, followed by declining of mitochondrial membrane potential, releasing of cytochrome c from mitochondria into the cytoplasm, and up-regulation of caspase-3, -9, and -12, CHOP and GRP78. These results suggest that death of MG63 cells induced by AE-PDT is triggered by ROS. Meanwhile, Mitochondria and ER serve as the subcellular targets, which are responsible for AE-PDT-induced death of MG63 cells.

Exploring a Novel Target Treatment on Breast Cancer: Aloe-emodin Mediated Photodynamic Therapy Induced Cell Apoptosis and Inhibited Cell Metastasis.

Photodynamic therapy (PDT) as a clinical cancer therapy, is a mild therapy, which involves application of photosensitizers (PSs) located in target cells and then irradiated by corresponding wavelength. The activation of PSs generates radical oxygen species (ROS) to exert a selective cytotoxic activity for the target cells. Aloe-emodin (AE) has been found to be an anti-tumor agent in many studies, and has also been demonstrated as a photosensitizer, in the recent years. In order to study the mechanisms of aloe-emodin as a photosensitizer, we investigated the mechanisms of photo-cytotoxicity induced by aloe-emodin in breast cancer MCF-7 cells in the present study. Analysis of cell proliferation evidenced that there was a drastic depression after photodynamic treatment with a series of aloe-emodin concentrations and light doses. We observed changes in apoptosis and demonstrated that the mechanisms of apoptosis were involved in mitochondrial and endoplasmic reticulum death pathways. The capacity of adhesion, migration and invasion of breast cells was measured using WST8 and transwell assay and demonstrated that AE-PDT significantly inhibited adhesion, migration and invasion of MCF-7cells. The expression of MMP2, MMP9, VEGF and Nrf2 demonstrated that the metastasis was related to oxidative stress. Analysis of changes in cytoskeleton components (F-actin) evidenced cytoskeleton disorganization after treatment with AE-PDT. Taken together, the present results indicated that PDT with aloe-emodin effectively suppressed cancer development in MCF-7cells, suggesting the potential of AE as a new photosensitizer in PDT which can provide a new modility for treating cancer.

The effect of aloe emodin-encapsulated nanoliposome-mediated r-caspase-3 gene transfection and photodynamic therapy on human gastric cancer cells.

Gastric carcinoma (GC) has high incidence and mortality rates in China. Surgery and chemotherapy are the main treatments. Photodynamic therapy (PDT) has become a new treatment modality, appearing in recent experimental studies and clinical trials in various tumors. This study explores the combined effect of gene transfection with PDT on GC cells using aloe emodin (AE)-encapsulated nanoliposomes, which acted as gene carrier as well as one photosensitizer (PS). AE-encapsulated nanoliposomes (nano-AE) were prepared by reverse evaporation method. Electron microscopy and nano-ZS90 analyzer were used to detect its morphology, size, and wavelength. Western blot was used to detect the expression of the caspase-3 after transfection. MTT assay and flow cytometry were employed to determine the cytotoxic and apoptotic rates, respectively. Hoechst 33342 staining was adopted to detect the morphological changes in death gastric cancer cells. Cellular reactive oxygen species (ROS) contents were measured by DCFH-DA staining. Outcomes demonstrated that the nano-AE has good properties as gene delivery carriers as well as a PS. The group in which the recombinant plasmid of r-caspase-3 was transfected had higher protein expression of the caspase-3 than controls, meanwhile the proliferation rates of the transfected cells were inhibited by the nano-AE-mediated PDT in an energy-dependent manner. In addition, in the transfected cells, the death rate increased to 77.3% as assessed 12 h after PDT (6.4 J/cm(2) ). Hochest 33342 staining also revealed that the death rate increased significantly in the transfected group compared with other groups. Compared to control groups, the production of ROS in nano-AE PDT group had quadrupled in SGC-7901 cells as early as 1 h after PDT, while it is similar to the group of nano-AE transfection and PDT. Nano-AE-mediated r-caspase-3 gene transfection coupled with PDT could inhibit the proliferation rate and increase the apoptotic rate remarkably in human gastric cancer cells.