scholarly journals An engineered nanocomplex with Photodynamic and Photothermal synergistic properties for cancer treatment

2021 ◽  
Author(s):  
Eli Varon ◽  
Gaddi Blumrosen ◽  
Moshe Sinvani ◽  
Elina Haimov ◽  
Shlomi Polani ◽  
...  

Photodynamic therapy (PDT) and photothermal therapy (PTT) are promising therapeutic methods for cancer treatment; however, as single modality therapies, either PDT or PTT are still limited in their success rate. A dual application of both PDT and PTT, in a combined protocol, has gained immense interest. In this study, gold nanoparticles (AuNPs) are conjugated with a PDT agent, meso-tetrahydroxyphenylchlorin (mTHPC) photosensitizer, designed as nanotherapeutic agents that can activate a dual photodynamic/photothermal therapy. The AuNP-mTHPC complex is biocompatible, soluable, and photostable. PDT efficiency is high because of immediate reactive oxygen species (ROS) production upon mTHPC activation by the 650 nm laser which decreased mitochondrial membrane potential (∆ψm). Likewise, the AuNP-mTHPC complex is used as a photoabsorbing (PTA) agent for PTT, due to efficient plasmon absorption and excellent photothermal conversion characteristics of AuNPs under laser irradiation at 532 nm. Under the laser irradiation of a PDT/PTT combination, a twofold phototoxicity outcome follows, compared to PDT-only or PTT-only treatment. This indicates that PDT and PTT have synergistic effects together as a combined therapeutic method. Hence, applying our AuNP-mTHPC may be a potential treatment of cancer in the biomedical field.

Parasitology ◽  
2018 ◽  
Vol 145 (9) ◽  
pp. 1251-1259 ◽  
Author(s):  
Patricia Andrea Garavaglia ◽  
María Fernanda Rubio ◽  
Marc Laverrière ◽  
Laura Mónica Tasso ◽  
Laura Edith Fichera ◽  
...  

AbstractSeveral ortho-naphthoquinones (o-NQs) have trypanocidal activity against Trypanosoma cruzi, the aetiological agent of Chagas disease. Previously, we demonstrated that the aldo-keto reductase from this parasite (TcAKR) reduces o-NQs, such as β-lapachone (β-Lap) and 9,10-phenanthrenequinone (9,10-PQ), with concomitant reactive oxygen species (ROS) production. Recent characterization of TcAKR activity and expression in two T. cruzi strains, CL Brener and Nicaragua, showed that TcAKR expression is 2.2-fold higher in CL Brener than in Nicaragua. Here, we studied the trypanocidal effect and induction of several death phenotypes by β-Lap and 9,10-PQ in epimastigotes of these two strains. The CL Brener strain was more resistant to both o-NQs than Nicaragua, indicating that greater TcAKR activity is unlikely to be a major influence on o-NQ toxicity. Evaluation of changes in ROS production, mitochondrial membrane potential, phosphatidylserine exposure and monodansylcadaverine labelling evidenced that β-Lap and 9,10-PQ induce different death phenotypes depending on the combination of drug and T. cruzi strain analysed. To study whether TcAKR participates in o-NQ activation in intact parasites, β-Lap and 9,10-PQ trypanocidal effect was next evaluated in TcAKR-overexpressing parasites. Only β-Lap was more effective and induced greater ROS production in TcAKR-overexpressing epimastigotes than in controls, suggesting that TcAKR may participate in β-Lap activation.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Chih-Chiang Chien ◽  
Ming-Shun Wu ◽  
Shih-Wei Chou ◽  
Ganbolor Jargalsaikhan ◽  
Yen-Chou Chen

Abstract Background Our previous studies have shown that evodiamine (EVO) as paclitaxel and nocodazole could trigger apoptosis in various human cancer cells including human renal cell carcinoma cells, colorectal carcinoma cells, and glioblastoma cells. This study aims to investigate the anti-cancer effects of EVO on human anaplastic thyroid carcinoma (ATC) cells, and underlining mechanism. Methods Two different endogenous p53 status human anaplastic thyroid carcinoma (ATC) cells including SW1736 (wtp53) and KAT4B (mutp53) were applied in the present study. The cytotoxicity of EVO on ATC cells was measured by MTT assay, and apoptosis and G2/M arrest were detected by propidium iodide (PI) staining followed by flow cytometry. Expression of indicated proteins was evaluated by Western blotting analysis, and pharmacological studies using chemical inhibitors and siRNA were performed for elucidating underlying mechanism. The roles of mitochondrial membrane potential and reactive oxygen species were investigated by flow cytometry using DiOC6 and DCFH-DA dye, respectively. Results SW1736 (wtp53) cells showed a higher apoptotic percentage than KAT4B (mutp53) cells in response to EVO stimulation via a flow cytometric analysis. Mechanistic studies showed that increased p53 and its downstream proteins, and disrupted MMP with increased intracellular peroxide production participated in EVO-induced apoptosis and G2/M arrest of SW1736 cells. In EVO-treated KAT4B cells, significant increases in G2/M percentage but little apoptotic events by EVO was observed. Structure-activity analysis showed that an alkyl group at position 14 was critical for induction of apoptosis related to ROS production and MMP disruption in SW1736 cells. Conclusion Evidence indicated that the endogenous p53 status affected the sensitivity of ATC cells to EVO-induced apoptosis and G2/M arrest, revealing the potential role of p53 related to increased ROS production and disrupted MMP in the anticancer actions of EVO, and alkylation at position 14 of EVO is a critical substitution for apoptosis of ATC cells.


Reproduction ◽  
2016 ◽  
Vol 152 (6) ◽  
pp. 695-704 ◽  
Author(s):  
Oriana Bonanno ◽  
Giulietta Romeo ◽  
Paola Asero ◽  
Franca Maria Pezzino ◽  
Roberto Castiglione ◽  
...  

The multifactorial pathological condition, that is, severe low sperm motility is a frequent cause of infertility. However, mechanisms underlying the development of this condition are not completely understood. Single abnormalities have been reported in sperm of patients with asthenozoospermia. In this study, we characterized, in 22 normozoospermic men and in 37 patients with asthenozoospermia, biochemical, molecular and genomic abnormalities that frequently occur in sperm of patients with asthenozoospermia. We evaluated a panel of sperm biomarkers that may affect the motility and fertilizing ability of sperm of patients with severe asthenozoospermia. Since reactive oxygen species (ROS) production is involved in the pathogenesis of such sperm abnormalities, we determined the association between ROS production and sperm abnormalities. High percentage of patients with severe asthenozoospermia showed increased basal and stimulated ROS production. Moreover, these patients showed increased mitochondrial DNA (mtDNA) copy number but decreased mtDNA integrity and they were associated with elevated ROS levels. Furthermore, mitochondrial membrane potential was also significantly decreased and again associated with high ROS production in these patients. However, the rate of nuclear DNA fragmentation was increased only in less than one-fifth of these patients. An important cohort of these patients showed multiple identical biochemical, molecular and genomic abnormalities, which are typical manifestations of oxidative stress. The most frequent association was found in patients with high ROS levels, increased mtDNA copy number and decreased integrity, and low MMP. A smaller cohort of the aforementioned patients also showed nDNA fragmentation. Therefore, patients with asthezoospermia likely present reduced fertilizing potential because of such composed abnormalities.


2017 ◽  
Vol 29 (5) ◽  
pp. 1039 ◽  
Author(s):  
J. M. Morrell ◽  
A. Lagerqvist ◽  
P. Humblot ◽  
A. Johannisson

Additional means are needed for evaluating the quality of stallion spermatozoa in semen doses for AI. Mitochondrial membrane potential (ΔΨm) has been linked to fertility in some species, but is rarely used in the evaluation of cooled stallion semen; metabolic activity may be associated with reactive oxygen species production (ROS). In the present study, ΔΨm and ROS production were measured in doses of cooled stallion semen. The effect of colloid centrifugation on these parameters was also investigated. In this case, colloid centrifugation involves centrifuging a sperm sample through a silane-coated silica colloid formulation to retrieve the most robust spermatozoa. High and low ΔΨm in cooled stallion semen varied between stallions and between ejaculates, but was not affected by single-layer centrifugation (SLC). The SLC-selected spermatozoa produced significantly less hydrogen peroxide than controls (P < 0.001), which could explain the increased longevity and retention of fertilising capacity seen in previous studies. For SLC samples, ΔΨm was positively associated with viable spermatozoa that were not producing reactive oxygen species (r = 0.49; P < 0.001) and negatively associated with ROS production (for superoxide: r = –0.4, P < 0.01; for hydrogen peroxide: r = –0.39, P < 0.05). There was no clear association between ΔΨm and ROS production in control samples.


2004 ◽  
Vol 164 (6) ◽  
pp. 803-809 ◽  
Author(s):  
Campbell W. Gourlay ◽  
Lindsay N. Carpp ◽  
Paul Timpson ◽  
Steven J. Winder ◽  
Kathryn R. Ayscough

Several determinants of aging, including metabolic capacity and genetic stability, are recognized in both yeast and humans. However, many aspects of the pathways leading to cell death remain to be elucidated. Here we report a role for the actin cytoskeleton both in cell death and in promoting longevity. We have analyzed yeast strains expressing mutants with either increased or decreased actin dynamics. We show that decreased actin dynamics causes depolarization of the mitochondrial membrane and an increase in reactive oxygen species (ROS) production, resulting in cell death. Important, however, is the demonstration that increasing actin dynamics, either by a specific actin allele or by deletion of a gene encoding the actin-bundling protein Scp1p, can increase lifespan by over 65%. Increased longevity appears to be due to these cells producing lower than wild-type levels of ROS. Homology between Scp1p and mammalian SM22/transgelin, which itself has been isolated in senescence screens, suggests a conserved mechanism linking aging to actin stability.


2011 ◽  
Vol 106 (11) ◽  
pp. 922-933 ◽  
Author(s):  
Natalia Rukoyatkina ◽  
Ulrich Walter ◽  
Andreas Friebe ◽  
Stepan Gambaryan

SummaryPlatelet activation is an irreversible process resulting in platelet apoptosis and necrosis, and circulating platelets contain many components of the apoptotic machinery. Cyclic guanosine monophosphate (cGMP) generated by nitric oxide (NO) activated soluble guanylyl cyclase (sGC) plays a crucial role in preventing platelet activation. However, in addition to activation of sGC, cGMP-independent NO effects in platelets have been described. To differentiate between cGMP-dependent and -independent NO effects on platelet apoptosis and reactive oxygen species (ROS) production, we generated platelet-specific sGC-deficient mice (PS-GCKO). Platelet apoptosis was induced by a combination of thrombin/convulxin (Thr/Cvx) and assessed by phosphatidylserine (PS) surface exposure, and loss of the mitochondrial membrane potential. NO-induced inhibition of PS externalisation was mediated only by cGMP-dependent mechanisms. Inhibition of the mitochondrial membrane potential decrease at low NO concentration was also cGMP-dependent but became cGMP-independent at high NO concentrations. In contrast, inhibition of ROS formation at any NO concentration was mediated by cGMP-independent mechanisms, very likely due to direct radical scavenging. NO inhibits platelet apoptosis by cGMP-dependent mechanisms and ROS production by cGMP-independent mechanisms. The PS-GCKO mouse model is an important tool for the differentiation of cGMP-dependent and -independent NO effects on platelets.


Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3132
Author(s):  
Thais P. Pivetta ◽  
Caroline E. A. Botteon ◽  
Paulo A. Ribeiro ◽  
Priscyla D. Marcato ◽  
Maria Raposo

Photodynamic therapy (PDT) and photothermal therapy (PTT) are photo-mediated treatments with different mechanisms of action that can be addressed for cancer treatment. Both phototherapies are highly successful and barely or non-invasive types of treatment that have gained attention in the past few years. The death of cancer cells because of the application of these therapies is caused by the formation of reactive oxygen species, that leads to oxidative stress for the case of photodynamic therapy and the generation of heat for the case of photothermal therapies. The advancement of nanotechnology allowed significant benefit to these therapies using nanoparticles, allowing both tuning of the process and an increase of effectiveness. The encapsulation of drugs, development of the most different organic and inorganic nanoparticles as well as the possibility of surfaces’ functionalization are some strategies used to combine phototherapy and nanotechnology, with the aim of an effective treatment with minimal side effects. This article presents an overview on the use of nanostructures in association with phototherapy, in the view of cancer treatment.


2020 ◽  
Vol 19 (3) ◽  
pp. 549-555 ◽  
Author(s):  
Adaze B. Enogieru ◽  
Sylvester I. Omoruyi ◽  
Okobi E. Ekpo

Purpose: To investigate the neuroprotective activity of the aqueous extract of Sutherlandia frutescens (SF) against 1-methyl-4-phenylpyridinium (MPP+)-induced toxicity in SH-SY5Y neuroblastoma cells. Methods: SH-SY5Y neuroblastoma cells were divided into different treatment groups: untreated cells, cells treated with MPP+ alone (2 mM), cells pretreated with SF (20 μg) prior to MPP+ (2 mM) treatment and cells treated with SF (20 μg) alone. Twenty-four hours after treatment with MPP+, cell viability was assessed by MTT assay, and changes in cell morphology, intracellular reactive oxygen species (ROS) production, mitochondrial membrane potential (MMP) as well as caspases 3/7 and 9 activities were determined. Results: Treatment of SH-SY5Y cells with MPP+ alone significantly altered cellular morphology, increased ROS production (p = 0.005), induced a significant loss of MMP (p = 0.0011) and caused significant apoptotic cell death, via the activation of caspases 3/7 and 9 (p ≤ 0.0359). These effects were however significantly (p ≤ 0.0359) attenuated in cells pre-treated with the aqueous leaf extract of SF, indicating the possible neuroprotective activity of the SF extract. Conclusion: The results of this study suggest that the aqueous leaf extract of SF may be neuroprotective against MPP+-induced toxicity via apoptotic cell death and inhibition of ROS production. Further mechanistic studies are required to validate the results of the present study using additional PD models, different extract preparations and active compounds derived from SF. Keywords: Parkinson’s disease, MPP+, Sutherlandia frutescens, Reactive oxygen species, Apoptosis, Neurodegeneration


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