- Role of arsenic (+3 oxidation state) methyltransferase in arsenic mediated APL treatment: an in vitro investigation. [Journal Article]
- MMetallomics 2018 May 18
- Arsenic (+3 oxidation state) methyltransferase (AS3MT) is a key enzyme responsible for arsenic metabolism in humans, which facilitates conversion of arsenic trioxide (As2O3) to more reactive metaboli...
Arsenic (+3 oxidation state) methyltransferase (AS3MT) is a key enzyme responsible for arsenic metabolism in humans, which facilitates conversion of arsenic trioxide (As2O3) to more reactive metabolites such as monomethylarsonous acid (MMAIII) and dimethylarsinous acid (DMAIII). However, it is unclear whether the biotransformation of arsenic by AS3MT contributes to the promotion of acute promyelocytic leukemia (APL) therapy. In order to understand the probable role of AS3MT in APL patients, we evaluated the effects of arsenite (iAsIII) and three mixed arsenicals (i.e., iAsIII, MMAIII and DMAIII, to mimic active arsenic species in the blood) on NB4 cell differentiation and apoptosis. Although the mixed arsenicals exhibited about 2 fold less effect on the induction of NB4 cell differentiation and PML-RARα fusion protein degradation, they showed 5 times stronger ability to induce apoptosis when compared with iAsIII. More importantly, the proliferation of NB4 cells was significantly (p < 0.05) inhibited in a transwell system co-cultured with AS3MT-transfected HepG2 cells after exposure to iAsIII, suggesting that the generation of methylated metabolites restrained cell proliferation. These findings indicate that the therapeutic efficacy of As2O3 (i.e., iAsIII) in APL patients is probably associated with the production of methylated arsenic metabolites (i.e., MMAIII and DMAIII) by AS3MT.
- Arsenic Trioxide-Coated Stent Is an Endothelium-Friendly Drug Eluting Stent. [Journal Article]
- AHAdv Healthc Mater 2018 May 16; :e1800207
- An ideal vascular stent would both inhibit in-stent restenosis (ISR) and promote rapid re-endothelialization. In the current study, the performance of arsenic trioxide (ATO)-drug eluting stent (AES) ...
An ideal vascular stent would both inhibit in-stent restenosis (ISR) and promote rapid re-endothelialization. In the current study, the performance of arsenic trioxide (ATO)-drug eluting stent (AES) is compared with the bare metal stent, poly-lactic-co-glycolic acid-coating metal stent, and rapamycin-drug eluting stent (RES). In vivo AES is shown to prevent neointimal hyperplasia more efficiently than the others when implanted into the carotid arteries of rabbits. Moreover, AES promotes endothelial cells proliferation and re-endothelialization more quickly than RES. In vitro ATO exposure significantly increases the viability, proliferation, adhesion, and spreading of primary porcine coronary artery endothelial cells (PCAECs), which are critical for endothelialization. However, ATO exposure reduces the viability of porcine coronary artery smooth muscle cells (PCASMCs). The evaluation of mitochondrial morphology, membrane potential, and function demonstrates that ATO at 2 µmol L-1 causes enlargement of the mitochondrion, enhancement of mitochondrial membrane potential, and adenosine triphosphate (ATP) production in PCAECs but not in PCASMCs. Thus, both in vivo and in vitro studies demonstrate that AES is an effective strategy for rapid re-endothelialization and inhibition of ISR.
- Low-Dose Arsenic Trioxide Modulates the Differentiation of Mouse Embryonic Stem Cells. [Journal Article]
- CRChem Res Toxicol 2018 May 24
- Arsenic (As) is a well-known environmental pollutant, while arsenic trioxide (ATO) has been proven to be an effective treatment for acute promyelocytic leukemia, however, the mechanism underlying its...
Arsenic (As) is a well-known environmental pollutant, while arsenic trioxide (ATO) has been proven to be an effective treatment for acute promyelocytic leukemia, however, the mechanism underlying its dual effects is not fully understood. Embryonic stem cells (ESCs) exhibit properties of stemness and serve as a popular model to investigate epigenetic modifiers including environmental pollutants. Herein, the effects of low-dose ATO on differentiation were evaluated in vitro using a mouse ESCs (mESCs) cell line, CGR8. Cells treated with 0.2-0.5 μM ATO for 3-4 days had slight inhibition of proliferation with elevation of apoptosis, but obvious alterations of differentiation by morphological checking and alkaline phosphatase (AP) staining. Moreover, ATO exposure significantly decreased the mRNA expression of the stemness maintenance genes including Oct4, Nanog, and Rex-1 ( P < 0.01), whereas obviously increased some tissue-specific differentiation marker genes such as Gata4, Gata-6, AFP, and IHH. These alterations were consistent with the differentiation phenotype induced by retinoic acid (RA) and the expression patterns of distinct pluripotency markers such as SSEA-1 and Oct4. Furthermore, low-dose ATO led to a quantitative increase in Caspase 3 (CASP3) activation and subsequent cleavage of Nanog around 27 kDa, which corresponded with the mouse Nanog cleaved by CASP3 in a tube cleavage assay. Taken together, we suggest that low-dose ATO exposure will induce differentiation, other than apoptosis, of ESCs, such effects might be tuned partially by ATO-induced CASP3 activation and Nanog cleavage coupling with other differentiation related genes involved. The present findings provide a preliminary action mechanism of arsenic on the cell fate determination.
- The apoptosis in arsenic-induced oxidative stress is associated with autophagy in the testis tissues of chicken. [Journal Article]
- PSPoult Sci 2018 May 14
- The aim of this study is to investigate whether arsenic (As) could induce testicular poisoning and influence the oxidative stress, apoptosis and autophagy in chickens. Seventy-two 1-day-old male Hy-l...
The aim of this study is to investigate whether arsenic (As) could induce testicular poisoning and influence the oxidative stress, apoptosis and autophagy in chickens. Seventy-two 1-day-old male Hy-line chickens were divided into 4 groups which were exposed to 0, 0.625, 1.25, and 2.5 mg/kg body weight (BW) of arsenic trioxide (As2O3) for 30, 60 and 90 days, respectively. Histological and ultrastructural changes, antioxidant enzyme activity, mRNA and protein levels of apoptosis and autophagy-related genes were detected. Oxidative stress injuries were obvious in the testes exposure to As2O3, which resulted in the decreased activities of antioxidant enzymes, such as catalase (CAT) and superoxide dismutases (SOD). Meanwhile, the changes of mRNA and protein levels of apoptosis and autophagy-related genes showed that As2O3 exposure induced enhanced testicular apoptosis and increased the levels of autophagy markers such as Microtubule associated protein light chains 3-II (LC3-II), dynein, Beclin-1, Autophagy associated gene 5 (ATG5) and ATG4B but not LC3-I and mammalian target of rapamycin (mTOR), and demonstrated the cross-talk between apoptosis and autophagy. Histological and ultrastructural abnormalities confirm the changes of the above indicators. Taken together, our findings provide deeper insights into roles of excessive apoptosis and autophagy in the aggravation of testicular damage, which could contribute to a better understanding of As2O3-induced testicular poisoning in chickens.
- [Preparation and in vitro evaluation of arsenic trioxide glioma targeting drug delivery system loaded by PAMAM dendrimers co-modified with RGDyC and PEG]. [Journal Article]
- ZZZhongguo Zhong Yao Za Zhi 2018; 43(8):1618-1625
- Arsenic trioxide (ATO) is an effective component of traditional Chinese medicine arsenic. The existing studies have shown its good inhibition and apoptosis ability on a variety of tumours. However, i...
Arsenic trioxide (ATO) is an effective component of traditional Chinese medicine arsenic. The existing studies have shown its good inhibition and apoptosis ability on a variety of tumours. However, its toxicity and difficulties in the permeability into the blood brain barrier (BBB) has the limitation in the application of glioma treatment. Polyamide-amine dendrimer (PAMAM) is a synthetic polymer with many advantages, such as a good permeability, stability and biocompatibility. Additionally, the 5th generation of PAMAM is an ideal drug carrier due to its three-dimensional structure. In this study, the 5th generation of PAMAM co-modified with RGDyC and PEG, then confirmed by ¹H-NMR. The average particle size of nanoparticles was about 20 nm according to the nanoparticle size-potential analyser and transmission electron microscopy. in vitro release showed that the nanocarrier not only has the sustained release effect, but also some pH-sensitive properties. The cell results showed that PAMAM co-modified with RGDyC and PEGAM has a lower cytotoxicity than the non-modified group in vitro. Accordingly, the drug delivery system has a better anti-tumour effect across the blood brain barrier (BBB) in vitro, which further proves the tumour targeting of RGDyC.
- Different administration patterns of docosahexaenoic acid in combating cytotoxic manifestations due to arsenic trioxide (acute promyelocytic leukemia drug) induced redox imbalance in hepatocytes. [Journal Article]
- POProstaglandins Other Lipid Mediat 2018 May 08; 136:64-75
- Docosahexaenoic acid (DHA) obtained from fish and plant sources is an essential dietary fatty acid and an important cell membrane structural component. The acute promyelocytic leukemia (APL) drug ars...
Docosahexaenoic acid (DHA) obtained from fish and plant sources is an essential dietary fatty acid and an important cell membrane structural component. The acute promyelocytic leukemia (APL) drug arsenic trioxide (As2O3), causes hepatotoxicity. We evaluated the protective potential of DHA as pre/combination/post-administration patterns against As2O3 induced toxicity. The therapeutic concentration of As2O3 (10 μM) resulted in cytotoxicity with a significant (p < 0.05) variation from the control group. Reduced cell viability, morphological alterations, enhanced LDH release and apoptosis were observed. The oxidative stress markers (lipid peroxidation, nitric oxide, and ROS) and hepatic enzymes (AST and ALT) and intracellular calcium levels were found to be elevated by the As2O3 administration. Reduction in levels of mitochondrial membrane potential, cellular free radical scavenging potential, intracellular proteins, ATPases and major antioxidants (catalase, SOD, GSH, and GPx) were also observed. Administration of DHA along with As2O3 as pre/combination administration patterns offered protection against As2O3 induced cytotoxicity at significant levels (p < 0.05) from As2O3 alone treated group. The cell viability and morphology were protected with reduced LDH release and apoptosis. The hepatic enzymes and oxidative stress markers were reduced with replenishment of mitochondrial membrane potential, free radical scavenging potential, intracellular proteins, ATPases and antioxidant levels. DHA pre/combination administration patterns showed protective potential against As2O3 with pre-treatment being the best and the post-treatment method failed to produce any protective effect.
- What has traditional Chinese medicine delivered for modern medicine? [Journal Article]
- ERExpert Rev Mol Med 2018 May 11; 20:e4
- The field of Traditional Chinese Medicine (TCM) represents a vast and largely untapped resource for modern medicine. Exemplified by the success of the antimalarial artemisinin, the recent years have ...
The field of Traditional Chinese Medicine (TCM) represents a vast and largely untapped resource for modern medicine. Exemplified by the success of the antimalarial artemisinin, the recent years have seen a rapid increase in the understanding and application of TCM-derived herbs and formulations for evidence-based therapy. In this review, we summarise and discuss the developmental history, clinical background and molecular basis of an action for several representative TCM-derived medicines, including artemisinin, arsenic trioxide, berberine and Salvia miltiorrhiza or Danshen. Through this, we highlight important examples of how TCM-derived medicines have already contributed to modern medicine, and discuss potential avenues for further research.
- Low Autophagy (ATG) Gene Expression Is Associated with an Immature AML Blast Cell Phenotype and Can Be Restored during AML Differentiation Therapy. [Journal Article]
- OMOxid Med Cell Longev 2018; 2018:1482795
- Autophagy is an intracellular degradation system that ensures a dynamic recycling of a variety of building blocks required for self-renewal, homeostasis, and cell survival under stress. We used prima...
Autophagy is an intracellular degradation system that ensures a dynamic recycling of a variety of building blocks required for self-renewal, homeostasis, and cell survival under stress. We used primary acute myeloid leukemia (AML) samples and human AML cell lines to investigate the regulatory mechanisms of autophagy and its role in AML differentiation. We found a significantly lower expression of key autophagy- (ATG-) related genes in primary AML as compared to healthy granulocytes, an increased autophagic activity during all-trans retinoic acid- (ATRA-) induced neutrophil differentiation, and an impaired AML differentiation upon inhibition of ATG3, ATG4D, and ATG5. Supporting the notion of noncanonical autophagy, we found that ATRA-induced autophagy was Beclin1-independent compared to starvation- or arsenic trioxide- (ATO-) induced autophagy. Furthermore, we identified PU.1 as positive transcriptional regulator of ATG3, ATG4D, and ATG5. Low PU.1 expression in AML may account for low ATG gene expression in this disease. Low expression of the autophagy initiator ULK1 in AML can partially be attributed to high expression of the ULK1-targeting microRNA-106a. Our data clearly suggest that granulocytic AML differentiation relies on noncanonical autophagy pathways and that restoring autophagic activity might be beneficial in differentiation therapies.
- Management of patients with acute promyelocytic leukemia. [Review]
- LLeukemia 2018 Apr 24
- With the introduction of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) acute promyelocytic leukemia (APL) has become from a detrimental to one of the most curable malignant diseases in hu...
With the introduction of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) acute promyelocytic leukemia (APL) has become from a detrimental to one of the most curable malignant diseases in humans. In particular, the chemotherapy-free regimen with ATO/ATRA has been proven to be highly effective in de novo APL and has become standard first-line therapy in younger adult, non-high-risk patients. Nevertheless, early death is still a major issue in APL, particularly in older patients, emphasizing the need of rapid diagnostics and supportive care together with immediate access to ATRA-based therapy. Despite the dramatic progress achieved in therapy of APL challenging situations occur, particularly in patients excluded from controlled studies with clinical knowledge mainly based on case reports and registries. Rapid identification and treatment of newly diagnosed patients as well as the management of toxicities and complications remain challenging. We offer up-to-date information and guidance regarding treatment of APL. Based on a literature review of existing scientific evidence we also discuss the approach to high-risk, elderly, pregnant and pediatric patients, treatment in patients with renal failure as well as of therapy-related or relapsed/refractory APL.
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- Arsenic trioxide induces apoptosis and inhibits the growth of human liver cancer cells. [Journal Article]
- LSLife Sci 2018 May 05
- CONCLUSIONS: Results clearly suggest that As2O3 restricted growth and induces apoptosis more in liver cancer cells as compared to normal cells. This finding suggests that it could be a promising potential therapeutic agent against liver cancer which need further testing by in-vivo investigations.