Attenuated Leishmanial sphingolipid induces apoptosis in A375 human melanoma cell via both caspase-dependent and -independent pathways

Parasites revive hope for cancer therapy

Parasites have attained a life-long stigma of being detrimental organisms with deleterious outcomes. Yet, recently, a creditable twist was verified that can dramatically change our perception of those parasites from being a source of misery to millions of people to a useful anti-cancerous tool. Various parasites have shown promise to combat cancer in different experimental models, including colorectal, lung, and breast cancers, among others. Helminths and protozoan parasites, as well as their derivatives such as Echinococcus granulosus protein KI-1, Toxoplasma gondii GRA15II, and Trypanosoma cruzi calreticulin, have demonstrated the ability to inhibit tumor growth, angiogenesis, and metastasis. This article provides an overview of the literature on various cancer types that have shown promising responses to parasite therapy in both in vitro and in vivo animal studies. Parasites have shown anti-neoplastic activity through a variety of mechanisms that collectively contribute to their anti-cancer properties. These include immunomodulation, inhibition of angiogenesis, and molecular mimicry with cancer cells. This review article sheds light on this intriguing emerging field and emphasizes the value of collaborative multidisciplinary research projects with funding agencies and pharmaceutical companies. Thus, these strategies would secure continuous exploration of this new avenue and accelerate the advancement of cancer therapy research. Although experimental studies are heavily conducted by leaps and bounds, further steps are definitely lagging. Upgrading research from the experimental level to the clinical trial would be a wise progression toward efficient exploitation of the anti-neoplastic capabilities of parasites, ultimately saving countless lives.

Non-thermal plasma induces apoptosis in melanoma cells via production of intracellular reactive oxygen species

Non-thermal atmospheric pressure dielectric barrier discharge (DBD) plasma may provide a novel approach to treat malignancies via induction of apoptosis. The purpose of this study was to evaluate the potential of DBD plasma to induce apoptosis in melanoma cells. Melanoma cells were exposed to plasma at doses that did not induce necrosis, and cell viability and apoptotic activity were evaluated by Trypan blue exclusion test, Annexin-V/PI staining, caspase-3 cleavage, and TUNEL® analysis. Trypan blue staining revealed that non-thermal plasma treatment significantly decreased the viability of cells in a dose-dependent manner 3 and 24 h after plasma treatment. Annexin-V/PI staining revealed a significant increase in apoptosis in plasma-treated cells at 24, 48, and 72 h post-treatment (p < 0.001). Caspase-3 cleavage was observed 48 h post-plasma treatment at a dose of 15 J/cm(2). TUNEL® analysis of plasma-treated cells demonstrated an increase in apoptosis at 48 and 72 h post-treatment (p < 0.001) at a dose of 15 J/cm(2). Pre-treatment with N-acetyl-L: -cysteine (NAC), an intracellular reactive oxygen species (ROS) scavenger, significantly decreased apoptosis in plasma-treated cells at 5 and 15 J/cm(2). Plasma treatment induces apoptosis in melanoma cells through a pathway that appears to be dependent on production of intracellular ROS. DBD plasma production of intracellular ROS leads to dose-dependent DNA damage in melanoma cells, detected by γ-H2AX, which was completely abrogated by pre-treating cells with ROS scavenger, NAC. Plasma-induced DNA damage in turn may lead to the observed plasma-induced apoptosis. Since plasma is non-thermal, it may be used to selectively treat malignancies.

Chlorpyrifos induces apoptosis and DNA damage in Drosophila through generation of reactive oxygen species

The present study investigated the apoptosis and DNA damage inducing potential of chlorpyrifos (CP) in Drosophila melanogaster. Third instar larvae of Drosophila were treated with different concentrations of CP (0.015-15.0 microg/L) for 2-48 h. Reactive oxygen species (ROS) generation, oxidative stress markers, DNA damage and apoptotic cell death end points were measured in them. A significant increase in DNA damage was concomitant with apoptotic mode of cell death in 15.0 microg/L CP-treated organisms for 24 and 48 h. Depolarization in mitochondrial membrane potential and increased casapase-3 and caspase-9 activities in these organisms indicated both as potential targets of CP. A significant positive correlation was observed among ROS generation, apoptosis and DNA damage. The study suggests that (i) ROS may be involved in inducing apoptosis and DNA damage in the CP-exposed larvae of Drosophila and (ii) D. melanogaster may be used as an alternative in vivo animal model for xenobiotics hazard assessment.

[Changes of mitochondrial apoptosis in spinal cord ischemia-reperfusion injury and the effects of Herba Erigerontis Breviscapi Injection preconditioning intervention in rabbits]

OBJECTIVE

To investigate the mechanisms of mitochondrial apoptosis in spinal cord ischemia-reperfusion injury and the effects of Herba Erigerontis Breviscapi Injection preconditioning intervention.

METHODS

Sixty Japanese rabbits were divided into sham-operated group, ischemia group, ischemia-reperfusion group (1, 6, 24 and 48 h), and Herba Erigerontis Breviscapi Injection group (1, 6, 24 and 48 h). Clamping the abdominal aorta was used to construct the rabbit model of spinal cord ischemia-reperfusion injury. The rabbits in the ischemia-reperfusion group and the Herba Erigerontis Breviscapi Injection group underwent reperfusion for 1, 6, 24, 48 h respectively after fifty-minute ischemia. The rabbits in the Herba Erigerontis Breviscapi Injection group were administered with Herba Erigerontis Breviscapi Injection at 9 mg/kg 30 minutes before ischemia. Rate of apoptotic cells was measured by flow cytometry; contents of caspase-9 and apoptosis-inducing factor (AIF) in cytoplasm and serum were measured by enzyme-linked immunosorbent assay.

RESULTS

Compared with the sham-operated group and the ischemia group, the rates of apoptotic cells, the contents of caspase-9 and AIF in cytoplasm were increased at all time points after reperfusion, and the contents of caspase-9 and AIF in serum were decreased after 1 h and 6 h reperfusion, and increased after 24 h and 48 h reperfusion in the ischemia-reperfusion group. Herba Erigerontis Breviscapi Injection intervention could decrease the rate of apoptotic cells and the contents of caspase-9 and AIF in cytoplasm and serum as compared with those in the ischemia-reperfusion group, and the effects appeared after 1 h reperfusion.

CONCLUSION

The apoptosis of nerve cells after spinal cord ischemia-reperfusion is related to the mitochondrial pathways. Herba Erigerontis Breviscapi Injection can inhibit nerve cell apoptosis by decreasing the contents of caspase-9 and AIF in cytoplasm and serum.