Immune response impairment, genotoxicity and morphological transformation induced by Taenia solium metacestode

126

Chromatin buds (CHB), broken eggs, or budding cell nuclei are structures similar to micronuclei (MN) in shape, structure, and size, which are linked to the main nuclei of cells by a thread or stalks of chromatin. They have been observed in numerous cell types and there are reports of their existence relating them with MN or with genotoxic events. However, there is no systematic study reporting their frequency and no experiment has been done to ascertain whether they are really induced by genotoxins. Furthermore, they have been discarded as genotoxic events with the argument that they are not formed in dividing cells. Studies are presented here that indicate that CHB can be considered as genotoxic events and that their origin is comparable to that of MN. Bromodeoxyuridine (BrdU) was used to label proliferating lymphocytes, which were later identified by means of an immunohistochemical method, using the H2O2-DAB stain. The results show that CHB are consistently formed where MN are seen. CHB were induced by the clastogen mitomycin C (MMC) as well as by the aneuploidogen colcemid, with frequencies similar to MN in both cases, and to multinucleated cells in the case of colcemid. CHB occur in lymphocytes of smokers with frequencies similar to those of MN, and we found that the infection with Taenia solium metacestodes induced a comparable increase of both MN and CHB frequency in lymphocytes from pigs.

Section: Discussionmentioning

confidence: 98%

Micronuclei and chromatid buds are the result of related genotoxic events

Serrano-García¹,

Montero‐Montoya²

2001

126

“…Neurocysticercosis is associated with several types of DNA damage in circulating lymphocytes from infected animals and patients [Herrera et al, 1994;. Micronuclei and chromatid buds are the result of related genotoxic events.…”

Section: Discussionmentioning

confidence: 99%

Genotoxicity of vesicular fluid and saline extract of Taenia solium metacestodes in somatic cells of Drosophila melanogaster

Silva

Costa-Cruz

Spanó

et al. 2006

Neurocysticercosis, the most common parasitic disease of the central nervous system, is caused by cysticerci of the helminth Taenia solium, which is prevalent in developing countries and is reemerging in affluent societies. This helminth is associated with brain tumors and hematological malignancies in humans. In the present study, we analyzed the genotoxicity of vesicular fluid (VF) and a saline extract (SE) of T. solium metacestodes in the Drosophila melanogaster wing somatic mutation and recombination test (SMART). Third-instar larvae derived from standard and high bioactivation crosses were treated for approximately 48 hr with 12.5, 25.0, and 50.0 microg/ml of VF and SE of T. solium metacestodes. Negative (phosphate buffered saline) and positive (10 mM urethane) controls were also included. The results showed that the two test compounds were genotoxic in both crosses of Drosophila. Nevertheless, further research is needed to determine the genotoxic potential of specific compounds present in VF and SE and their role in the development of cancer.

“…A putative small RNA molecule secreted by T. solium cysticerci [Molinari et al, 1990] has the capacity to transform Syrian hamster embryo cells in vitro [Herrera et al, 1994]. We have found that this molecule induces chromosome damage in human cultured lymphocytes, suggesting that this factor could induce genetic instability in infected individuals [Herrera and Ostrosky-Wegman, 2001].…”

Section: Modulation Of Proliferation-antiproliferation Pathways and Cmentioning

confidence: 97%

Role of infectious diseases in human carcinogenesis

Herrera

Benı́tez-Bribiesca

Mohar

et al. 2005

Self Cite

The burden of human infectious diseases remains a public health problem worldwide. At least 2 billion people are affected by viral infections, and a similar number by bacteria or helminths. The long-term effects of these maladies have raised particular concern since some infectious agents have been associated with chronic human diseases, especially cancer. It is estimated that 13-20% of the world cancer cases are associated with some virus, bacteria, or helminth, e.g., human papillomavirus, Helicobacter pylori, and Schistosoma haematobium that cause cervical, stomach, and urinary bladder cancer, respectively. Certain associations between infection and malignancy are strong and irrefutable; others are still speculative. This article reviews the infectious agents that have been associated with cancer and current knowledge about the mechanisms underlying these associations.