Urinary and cutaneous complications of sulphur mustard poisoning preceding pulmonary and ocular involvement: an unusual sequence of symptoms

Alteration of miRNA expression in a sulfur mustard resistant cell line

BACKGROUND

MicroRNAs (miRNAs) are responsible for post-transcriptional control of protein expression. Numerous miRNAs have been identified to be responsible for the resistance of tumor cells to cytostatic drugs. Possibly, the same miRNAs also play a role in the sulfur mustard (SM)-resistance of the keratinocyte cell line HaCaT/SM as alkylating cytostatics exhibit similar cytotoxic effects as SM.

METHODS

Basal expression levels of 1920 miRNAs in total were analyzed in HaCaT/SM compared to the origin human keratinocyte cell line HaCaT. The effect for selected miRNAs on cell survival was analyzed using antagomirs for ectopic miRNA level decrease or miRNA mimics for increase. Cell survival was calculated as SM dose-dependent-curves.

RESULTS

Out of 1920 miRNAs analyzed, 49 were significantly up- and 29 were significantly downregulated in HaCaT/SM when compared to HaCaT controls. Out of these, 36 could be grouped in miRNA families. Most of the 15 miRNA family members showed either a common increase or decrease. Only the members of miR-10, miR-154, miR-430 and miR-548 family showed an inconsistent picture. The ectopic increase of miR-181 in HaCaT/SM had a positive effect on cell survival in the presence of SM.

CONCLUSION

In summary, the extensive differences in miRNA expression pattern between these cell lines indicate that specific miRNAs may play a role in the resistance mechanism against sulfur mustard. The miR-125b-2 and miR-181b alone are not responsible for the resistance development against SM, but an ectopic increase of miR-181 even enhances the SM resistance of HaCaT/SM. Improving the resistance in normal keratinocytes by treatment with either both miRNAs together or a different combination might be used as an initial step in development of an innovative new drug or prophylactic agent against SM.

Effects of sulfur mustard on mesenchymal stem cells

Chronic wound healing disorders that occur as a result of a sulfur mustard (SM) exposure present a particular challenge. These chronic wounds are similar to other chronic wounds. In the past, it has been shown that mesenchymal stem cells (MSC) play an important role in the healing of chronic wounds. An important property to support wound healing is their ability to migrate. However, we were able to show that SM leads to a reduction in MSC migration even at low concentrations. Currently, exposed MSCs are still able to differentiate. Further alterations are not known. The current investigation therefore focused onto the question how SM affects MSC.

MATERIAL & METHODS

The effect of SM on MSC was investigated. Here, the alkylation of DNA was considered, and DNA adducts were quantified over a period of 48h. The modification of the nuclei under the influence of SM was analyzed as well as proliferation of the cells by immunohistochemical staining with Ki-67 and quantification. For the quantification of the apoptosis rate, antibodies against cleaved Caspase-3, 8, and apoptosis inducing factor (AIF) were used. The senescence analysis was performed after histological staining against β-galactosidase. Quantifications were carried out by using the TissueQuest System and the software TissueFAX.

RESULTS

SM exposure of MSC results in a dose dependent formation of nuclear DNA adducts. 4h after exposure the cells display a decreasing concentration of DNA adducts. This process is accompanied by a change of nuclei shape but without an increase of apoptosis induction. In parallel the number of cells undergoing senescence increases as a function of the SM concentration.

DISCUSSION

SM exposure of MSC leads to adduct formation on chromosomal DNA. These DNA adducts can be reduced without MSC are undergoing apoptosis. This indicates an active DNA damage response (DDR) pathway in combination with the formation of persistent nuclear DNA damage foci. This process is accompanied by a reduced capability of proliferation and a transition into the senescent state.

Mycosis fungoides two decades after exposure to sulphur mustard: a follow-up of 1100 victims

BACKGROUND

Sulphur mustard (SM) is an alkylating chemical warfare agent which causes acute and chronic injuries to the eyes, skin, lung and respiratory tract.

OBJECTIVE

We aimed to investigate the relationship between SM poisoning and Mycosis fungoides (MF) as a late consequence.

MATERIAL AND METHODS

In this retrospective study, the medical files of 1100 Iranian veterans confirmed to have exposure to SM agent during the Iraq-Iran war of the 1980s were reviewed.

RESULTS

All 10 cases with MF were confirmed by clinical and histopathological examinations. The mean age of the studied subjects was 43.3 ± 9.8 (years). In comparison to MF incidence rate in Iranian general population (0.39/100 000 person-years), we found an incidence rate of 0.799/100 000 person-years for MF among those who had short-term exposure to SM. The most common sites for SM lesions were flexural and thin skin areas. The main limitation was the retrospective design.

CONCLUSION

This study indicates that the risk of MF in those exposed to SM may increase over time. Therefore, their follow-up is recommended.

Skin manifestations in sulfur mustard exposed victims with ophthalmologic complications: Association between early and late phase

Context

Sulfur mustard (SM) was used during the Iraq-Iran war (1980–1988). Exposed veterans continue to suffer from its ocular, skin, and respiratory complications.

Objective

We aimed to evaluate associations between early (at the time of acute exposure) and decades later skin manifestations in individuals with severe ophthalmologic complications secondary to sulfur mustard exposure.

Materials and methods

One hundred forty-nine veterans with severe ocular injuries were evaluated for acute and chronic skin complications. Logistic regression models were used to examine the associations between early and late skin manifestations.

Results

Late skin complaints were observed in nearly all survivors who had early skin lesions (131 out of 137; 95.62%). Seven out of 12 patients (58.33%) who did not have early skin lesions ultimately developed late skin complications. There was a significant relationship between the presence of lesions at the time of exposure and developing late skin complaints (two-sided Fisher's exact test, OR = 15.59, p < 0.001). There was an association between having at least one early skin lesion and occurrence of late skin complications. Survivors with blisters at the time of chemical exposure were more likely to complain of itching (95% CI: 3.63–25.97, p < 0.001), burning (OR = 11.16; 95% CI: 2.97–41.89, p < 0.001), pigmentation changes (OR = 10.17; 95% CI: 2.54–40.75, p = 0.001), dryness (OR = 6.71, 95% CI: 1.22–37.01, p = 0.03) or cherry angioma (OR = 2.59; 95% CI:1.21–5.55, p = 0.01) during the late phase. Using multivariate logistic models, early blisters remained significantly associated with latent skin complaints. Of note, the genitalia and great flexure areas were the most involved anatomical sites for both early and late skin lesions in SM exposed survivors.

Conclusion

According to this study, the presence of blisters at the time of exposure to SM is the most important predictor of developing dermatologic complications decades later in patients with severe ophthalmologic complications from sulfur mustard exposure.

Development of the sulfur mustard resistant keratinocyte cell line HaCaT/SM

Pairs of corresponding cytotoxic drug sensitive and resistant cell lines are powerful tools to develop treatment strategies. Developing cytotoxic drug resistant cell lines is a well-established method in cancer research. In more than fifty years of sulfur mustard (SM) resistant research such a cell pair has never been produced. Hereinafter we describe the first successful approach to develop a SM resistant keratinocyte cell line. Starting with the SM sensitive keratinocyte cell line HaCaT we used a strategy of continuous exposure with gradually increased concentrations. Cells were cultured in total for more than 40 months starting with an initial concentration of 0.07μM SM twice a week up to a final concentration of 7.2μM SM. The achieved cell line HaCaT/SM had an LC50 resistance increase of 4.7-fold and an LC90 increase of 8.2-fold. Hereinafter we demonstrate the production of the first sulfur mustard (SM) resistant cell line. The new achieved cell line called HaCaT/SM is able to tolerate a continuous exposure of an SM concentration, which is associated with an inhibitory effect of 93% within the original HaCaT cells, which were used as starting point.

Alteration of miRNA expression in early endothelial cells after exposure with sub-lethal sulfur mustard concentrations

BACKGROUND/AIM

Sulfur mustard (SM) is known to induce chronic wound healing disorders as well as disturbed endothelial regeneration. It is known that wound healing as well as endothelial regeneration are controlled by micro-RNA (miRNA). As nothing is known today about the effect of SM onto miRNA expression we wanted to investigate whether there is an effect of sub-lethal concentrations of SM onto the miRNA expression of endothelial cells.

METHODS

Early endothelial cells (EEC) were incubated with different sub-lethal concentrations of sulfur mustard (SM) in-vitro. Cells were subsequently analyzed with respect to survival and colony-forming capacity. In addition, the nuclear structure was investigated with respect to apoptosis, micronuclei or abnormal forming using the MAA assay. Six hundred sixty-seven different miRNA species from both, treated and untreated EEC were quantified.

RESULTS

The sub-lethal concentrations IC1, IC5 or IC10 were used. While performing the MAA assay the cells showed a time dependent change in nucleus structure from normal to abnormal, without significant changes in apoptosis being observed. In the colony-forming assay a weak cell proliferation capacity was revealed. Under all conditions they lost their capacity to form colonies. Out of 667 investigated miRNAs in total 66 showed a significant change in expression upon incubation with SM. 19 miRNAs were up-regulated and 47 down-regulated. The strongest correlation between SM concentration and up-regulation was found for mmu-miR-92a-3p* (hsa-miR-92a). Seven miRNAs showed a change in expression similar to endothelial cells from younger or older mice.

CONCLUSION

The presented work demonstrates that sulfur mustard (SM) has an effect on miRNA expression in general. The observed changes in expression in early endothelial cells correlates to the known effects of SM. Further studies have to investigate if these findings are in direct dependence and if these relationships can be used to alleviate the sulfur mustard induced clinical damage.

Mesenchymal stem cells are highly resistant to sulfur mustard

The effect of sulfur mustard (SM) to the direct injured tissues of the skin, eyes and airways is well investigated. Little is known about the effect of SM to mesenchymal stem cells (MSC). However, this is an interesting aspect. Comparing the clinical picture of SM it is known today that MSC play an important role e.g. in chronic impaired wound healing. Therefore we wanted to get an understanding about how SM affects MSC and if these findings might become useful to get a better understanding of the effect of sulfur mustard gas with respect to skin wounds. We used mesenchymal stem cells, isolated from femoral heads from healthy donors and treated them with a wide range of SM to ascertain the dose-response-curve. With the determined inhibitory concentrations IC1 (1μM), IC5 (10μM), IC10 (20μM) and IC25 (40μM) we did further investigations. We analyzed the migratory ability and the differentiation capacity under influence of SM. Already very low concentrations of SM demonstrated a strong effect to the migratory activity whereas the differentiation capacity seemed not to be affected. Putting these findings together it seems to be likely that a link between MSC and the impaired wound healing after SM exposure might exist. Same as in patients with chronic impaired wound healing MSC had shown a reduced migratory activity. The fact that MSC are able to tolerate very high concentrations of SM and still do not lose their differentiation capacity may reveal new ways of treating wounds caused by sulfur mustard.

A clinicopathological approach to sulfur mustard-induced organ complications: a major review

CONTEXT

Sulfur mustard (SM), with an old manufacturing history still remains as potential threat due to easy production and extensive effects.

OBJECTIVES

Increasing studies on SM indicates the interest of researchers to this subject. Almost all human body organs are at risk for complications of SM. This study offers organ-by-organ information on the effects of SM in animals and humans.

METHODS

The data sources were literature reviews since 1919 as well as our studies during the Iraq-Iran war. The search items were SM and its all other nomenclatures in relation to, in vivo, in vitro, humans, animals, eye, ocular, ophthalmic, lungs, pulmonary, skin, cutaneous, organs and systemic. Amongst more than 1890 SM-related articles, 257 more relevant clinicopathologic papers were selected for this review.

RESULTS

SM induces a vast range of damages in nearly all organs. Acute SM intoxication warrants immediate approach. Among chronic lesions, delayed keratitis and blindness, bronchiolitis obliterans and respiratory distress, skin pruritus, dryness and cancers are the most commonly observed clinical sequelae.

CONCLUSION

Ocular involvements in a number of patients progress toward a severe, rapid onset form of keratitis. Progressive deterioration of respiratory tract leads to "mustard lung". Skin problems continue as chronic frustrating pruritus on old scars with susceptibility to skin cancers. Due to the multiple acute and chronic morbidities created by SM exposure, uses of multiple drugs by several routes of administrations are warranted.

Sézary syndrome, Kaposi sarcoma and generalized dermatophytosis 15 years after sulfur mustard gas exposure

BACKGROUND

The relationship between compromised immune system and the development of malignancy, generalized dermatitis, and infection after sulfur mustard gas exposure has been established.

MAIN OBSERVATION

We introduce a 58-year-old man with an abrupt, de novo and erythrodermic eruption in 2002 that was previously exposed to sulfur mustard during the Iran - Iraq war in 1987. Six weeks after the onset of diffuse eruption, he developed papules on the glans penis and generalized dermatophytosis. A biopsy of his eruption was consistent with cutaneous T-cell lymphoma/Sézary syndrome. A complete blood count demonstrated leukocytosis, eosinophilia and atypical lymphocytosis. Subsequently, Sézary syndrome was confirmed and T-cell count with increased CD4/CD8 in flow cytometry. The biopsy of his penile papules was consistent with Kaposi's sarcoma.

CONCLUSION

These findings suggest a causative relationship between sulfur mustard gas exposure, cutaneous T cell lymphoma and immune compromised state with opportunistic infections.

Mustard gas toxicity: the acute and chronic pathological effects

Ever since it was first used in armed conflict, mustard gas (sulfur mustard, MG) has been known to cause a wide range of acute and chronic injuries to exposure victims. The earliest descriptions of these injuries were published during and in the immediate aftermath of the First World War, and a further series of accounts followed the Second World War. More recently, MG has been deployed in warfare in the Middle East and this resulted in large numbers of victims, whose conditions have been studied in detail at hospitals in the region. In this review, we bring together the older and more recent clinical studies on MG toxicity and summarize what is now known about the acute and chronic effects of the agent on the eyes, skin, respiratory tract and other physiological systems. In the majority of patients, the most clinically serious long-term consequences of MG poisoning are on the respiratory system, but the effects on the skin and other systems also have a significant impact on quality of life. Aspects of the management of these patients are discussed.