Aim: Amyotrophic lateral sclerosis (ALS) is a progressive disease of unknown etiology, characterized by degeneration of motoneurons and skeletal muscle strength decline that progressively evolves to respiratory failure and death. A key point in the therapeutic approach is to understand the pathological processes associated with disease evolution. In spite of intensive research on the molecular/cellular mechanisms involved in ALS initiation and progression disease etiology, unfortunately, poorly understood and there is no efficient specific/decisive treatment for ALS patients. The aims of the present study are to identify specific factors in the cerebrospinal fluid (CSF) of ALS patients and to test their potential relevance to the etiology of this disease. Methods: Peptides were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS). Motor activity of mice was tested by the Rota-rod test and peptide-induced inflammation was assessed by induction nitric oxide synthase activity in BV2 microglia cells. Results: Analysis of CSF samples of ALS patients (n = 15) detected two peptides, C-terminal fragments of transthyretin and osteopontin, which were absent in a control group (n = 15). In addition to being potential biomarker candidates, the relevancy of these peptides to the disease etiology was tested by assessing their effects on motor activity in mice and inflammation model in cell culture. Intranasal administration of the peptides reduced motor activity in the Rota-rod test and activated lipopolysaccharide-induced inflammation in BV2 microglia cells. Conclusions: These findings suggest that during ALS onset and progression two potentially neurotoxic peptides are formed, released, or penetrated the central nervous system thus inducing neuroinflammation and neurodegeneration.
Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative motor neuron disease that involves activation of the immune system and inflammatory response in the nervous system. Reduced level of the immuno-modulatory and anti-inflammatory protein alpha-1-antitrypsin (AAT) is associated with inflammation-related pathologies. The objective of the present is to determine AAT levels and IL-23 in the cerebrospinal fluid (CSF) of ALS patients and control group.
The use of chemical warfare agents is of serious concern for the military and civilian populations. The experience of the twentieth and twenty-first centuries reveals that nerve agents and mustard gas are the main chemicals used for mass destruction. The vesicating effect of mustard gas is the main focus of this review. Its powerful irritating activities in the dermal, pulmonary and ocular systems stem from alkylation of macromolecules and induction of inflammatory response and oxidative stress. This review describes the pathological processes occurring upon exposure to mustard gas and the molecular and cellular events leading to its devastating health effects. Based on its mechanism of action, a series of potential antidotes and their combinations was proposed as countermeasures for mustard gas toxicity. In spite of the intensive research and information on this vesicant, much effort is needed for further elucidation of its mode of action and improvement of antidotal activity.
Methylmercury (MeHg) is an environmental neurotoxicant associated with aberrant central nervous system (CNS) functions. In this study, we examined the protective effect of a novel anti-inflammatory and cytoprotective nonapeptide, termed IIIM1, against MeHg-induced toxicity in cultured rat neonatal primary astrocytes. Astrocytes were pretreated for 66 h with 5 μg/ml IIIM1 (4.95 μM) followed by 6 h exposure to MeHg (5 μM). MeHg significantly increased F(2)-isoprostane generation, a lipid peroxidation biomarker of oxidative injury and this effect was significantly reduced upon pre-treatment with IIIM1. The MeHg-induced increase in levels of prostaglandin E(2) (PGE(2)), biomarkers of inflammatory responses, was also decreased in the peptide-treated cells. Mass spectrometry analysis revealed no chemical or binding interaction between MeHg and IIIM1, indicating that intracellular cytoprotective mechanism of action accounts for the neuroprotection rather than direct intracellular neutralization of the neurotoxicant with the peptide. These findings point to therapeutic potential for IIIM1 in a plethora of conditions associated with reactive oxygen species (ROS) generation. The implication of these findings may prove beneficial in designing new treatment modalities that efficiently suppress neurotoxicity, triggered not only by MeHg, but also by other metals and environmental agents, as well as chronic disease conditions that inherently increase reactive radical production and inflammatory signaling.
The purpose of the present study was to develop a peptide for treatment of multiple sclerosis (MS). We have tested the effect of a novel anti-inflammatory peptide (KGHYAERVG, termed IIIM1) on experimental autoimmune encephalitis (EAE), an animal model of MS. Our findings demonstrate significant reduction in neurological score following oral administration of IIIM1. Structural studies revealed that the entire peptide is required for activity. The peptide caused significant reduction in IL17, interferon gamma, IL23 and IL12 production by isolated splenocytes and concomitant elevation of anti-inflammatory cytokines. IIIM1 elevated T regulatory cells (Tregs, CD4(+)CD25(+)FoxP3(+)) in brain and spleen of EAE mice. Similar proliferative effect was observed in isolated human and mouse Tregs in vitro. Stimulation of Tregs by IIIM1 caused production of a new peptide termed RA1 present in Oryza Sativa Japonica group. This Japanese rice peptide ameliorated neurological symptoms in the EAE model. Similar beneficial effect was observed upon oral administration of an extract of Japanese rice. In conclusion, oral treatment with IIIM1 ameliorates EAE symptoms via stimulation of Tregs to proliferate and produce RA1 which reduces EAE symptoms. RA1 might be involved in the relatively low prevalence of MS in Japan and other Japanese rice-eating populations.
Anti-inflammatory drugs are often of limited use due to low efficacy and toxic effects. The present study describes the anti-inflammatory effects of a novel nonapeptide termed IIIM1, using the mouse hind paw edema as an experimental model of inflammation. Multiple prophylactic injections of IIIM1 resulted in a significant reduction in carrageenan-induced foot pad swelling, both in mice and rats. A single prophylactic treatment of the peptide caused the maximal effect at 7-9 days between the initial peptide treatment and the subsequent carrageenan injection. A reduced inflammatory reaction was observed in transgenic mice constitutively expressing the peptide. A marked decrease in oxidative burst was observed in activated peritoneal macrophages obtained from peptide-treated mice. Furthermore, the sera of IIIM1-treated mice caused a significant decrease in the oxidative burst of macrophages. In addition, the reduction of hind paw swelling in mice injected with the sera of IIIM1-treated mice strongly suggests the presence of a circulating inducible factor responsible for the anti-inflammatory effect of the peptide. Previous LC/MS/MS analysis revealed the presence of a new peptide, termed RA1, in the sera of IIIM1-treated mice. RA1 was identified as a fragment of the Oryza Sativa Japonica protein. The anti-inflammatory effect of RA1 as evidenced by the reduction in carrageenan-induced hind paw swelling corresponded with the decrease in the oxidative burst of macrophages treated in vitro with this peptide. In conclusion, both IIIM1 and RA1 represent potential agents for the efficient treatment of inflammatory diseases that are currently incurable using presently available drugs.
The increasing exposure to environmental neurotoxicants in the last decades caused serious health problems in the world population. Some of the neurotoxic agents are being used in agriculture and household such as insecticides and rodenticides and others are of natural origin like snake and scorpion venoms. Additional group of harmful substances is the chemical warfare agents including nerve and blistering agents that are known for their disastrous effects on neuronal tissues. The present paper presents a combination of epidemiological/clinical and molecular approaches for investigating the effect of certain groups of neurotoxicants on a variety of pathologies. The work of Finkelstein and coworkers describes epidemiological and clinical studies on acute and chronic organophosphate (OP)-induced neurotoxicity in certain populations in Israel. They mainly investigated the neurotoxic effects of low-level long-term exposure to OP in agricultural areas but also dealt with acute exposures as well. A molecular approach to OP mechanism of neuronal injury was described by Milatovic and coworkers. They demonstrated OP-induced oxidative injury in pyramidal neurons in the CA1 hippocampal area and its suppression by antioxidants. Lecht and coworkers described the novel snake venom angioneurins as important mediators of the physiological cross-talk between the cardiovascular and nervous systems. They also showed that under certain conditions these angioneurins may induce pathologies such as tumor development or disruption of the vascular barrier function during envenomation. Additional mechanistic/therapeutic approach was presented by Brodsky, Rosengarten, Proscura, Shapira and Wormser. They developed a novel anti-inflammatory peptide that reduced skin irritation induced by heat and sulfur mustard (SM) stimuli. Since SM causes neuropsychiatric symptoms and alterations in neurological functions this peptide may serve as a potential treatment of neuronal injuries caused by environmental neurotoxicants. These reviews highlight different aspects of neurotoxicity, addressing epidemiology and mechanisms of toxicity; and identifying novel potential therapies.
Abstract Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by a loss of immunologic tolerance, production of auto-antibodies and inflammatory damage in multiple organs. We have tested the effect of anti-inflammatory peptide, a H2A histone fragment, termed IIIM1 on MRL/lpr mice, an animal model of SLE. Oral administration of IIIM1 at early stage of disease caused reduction in proteinuria and serum anti-dsDNA antibodies. Starting the treatment at advanced stage of disease resulted in prolonged animal survival, decreased lymphadenosis and reduced levels of pathogenic or abnormal double negative CD4-CD8- cells and B220+ cells in lymph nodes and spleen. We discovered that IIIM1 induces the production of an additional peptide, a fragment of alpha-1-antitrypsin, termed UBE. Relatively low dose (1µg/kg) of UBE reduced proteinuria and hematuria in MRL/lpr mice. The beneficial effect of the peptide was corroborated by histological examination. Furthermore, a significant reduction in serum IL17, IL12 and anti dsDNA antibodies was observed in the UBE-treated mice. Isolated CD4 cells incubated with the peptide showed similar cytokine profile. Decreased levels of double negative CD4-CD8- and B220+ cells were determined in lymph organs of UBE-treated animals. The beneficial effects of both UBE and IIIM1 suggest these peptides as potential drugs for SLE.
The primary purpose of the present study was to investigate the mechanism of the counter-irritating activity of topical iodine against skin lesions induced by chemical and thermal stimuli. The hypothesis that iodine exerts its activity by inducing an endogenous anti-inflammatory factor was confirmed by exposing guinea pig skin to heat stimulus followed by topical iodine treatment and skin extraction. Injection of the extract into naïve guinea pigs reduced heat-induced irritation by 69%. The protective factor, identified as a new nonapeptide (histone H2A 36-44, H-Lys-Gly-Asn-Tyr-Ala-Glu-Arg-Ileu-Ala-OH), caused reduction of 40% in irritation score in heat-exposed guinea pigs. The murine analog (H-Lys-Gly-His-Tyr-Ala-Glu-Arg-Val-Gly-OH, termed IIIM1) reduced sulfur mustard (SM)-induced ear swelling at a dose-dependent bell-shape manner reaching peak activity of 1 mg/kg. Cultured keratinocytes transfected with the peptide were more resistant towards SM than the control cells. The peptide suppressed oxidative burst in activated neutrophils in a concentration-dependent manner. In addition, the peptide reduced glucose oxidase-induced skin edema in mice at a dose-dependent bell-shape manner. Apart from thermal and chemical-induced skin irritation this novel peptide might be of potential use in chronic dermal disorders such as psoriasis and pemphigus as well as non-dermal inflammatory diseases like multiple sclerosis, arthritis and colitis.
Exposures to skin irritants frequently occur in daily life at the workplace, in laboratories and during housekeeping. Apart from the physical protective countermeasures, there is a need for pharmacological preparations for the topical treatment of the exposed skin to prevent the development of burns. Exposure of the skin to a chemical irritant initiates an inflammatory response which progressively intensifies, leading to epidermal and dermal lesions. Topical treatment with povidone-iodine (PI) or iodine ointment significantly reduced skin damage induced by mustard gas (sulfur mustard), hydrofluoric acid and other chemical irritants. Human studies showed the efficacy of PI and iodine against thermal burns. The combination of anti-inflammatory agents and iodine increased the counterirritating activity. Both human and experimental animal studies demonstrated that the ointment should be immediately applied after occurrence: the earlier the treatment, the better the therapeutic effect. In addition, the ointment should be left on the skin long enough for achieving the therapeutic effect. This simple topical treatment can prevent suffering, skin transplantation and complications associated with skin burns.
One of the major limitations of current methods of biological detection of exposure to hazardous environmental agents is their inability to detect long-term exposures. In the current study we examined the potential of a new bioassay based on the hypothesis that serum of exposed individuals contains a toxic factor(s) produced by an affected cell/tissue. The procedure included exposure of neuronal PC12 cell cultures to sera of rats treated once with the organophosphate chlorpyrifos. Samples taken 4 weeks after chlorpyrifos exposure reduced nerve growth factor (NGF)-induced neurite outgrowth by 40%. This effect lasted 6 weeks after treatment, whereas motor activity and cholinesterase activity returned to normal levels within 1 week. These results demonstrate the potential of the proposed method to detect environmental exposures long after they have occurred.
Sulfur mustard (SM), also termed mustard gas, is a potent vesicant that elicits an inflammatory response upon exposure of the skin. Evaluation of mouse ear 3 h after SM exposure revealed acute inflammatory-cell aggregates in the vascular beds accompanied by strongly TNF-alpha-positive neutrophils. Eight hours after SM exposure, this phenomenon became intensified and associated with infiltration into the adjacent dermis. In ear skin topically treated with iodine, however, no inflammatory cells were observed 3 h after SM exposure; 8 h postexposure, blood vessels contained very few TNF-alpha-positive inflammatory cells. Since TNF-alpha induction was shown to be associated with reactive oxygen species production, we studied the effect of iodine on activated peritoneal mouse neutrophils. Iodine elicited a concentration-dependent reduction in the oxidative burst of activated neutrophils. Iodine also scavenged hydroxyl radicals generated by glucose oxidase in a concentration-dependent manner. The involvement of TNF-alpha in SM-induced skin toxicity was confirmed by reduction of 49 and 30% in ear edema following administration of 1 and 2 mu g anti-TNF-alpha antibodies, respectively. These findings were corroborated by quantitative analysis of the histological findings showing 46% reduction in acute inflammation and no signs of subacute inflammation in the treated group, in contrast to the control group treated with SM only. Other epidermal (microblister formation, ulceration, and necrosis) and dermal (neutrophilia, hemorrhage, and necrosis) parameters also showed marked reductions in the antibodies-treated group in comparison to controls. The combination of iodine and antiTNF-alpha antibodies might constitute a new approach for treatment of SM-exposed individuals.
Sulfur mustard (SM) is powerful alkylator and highly cytotoxic blisterogen in both humans and animals. This study in male guinea pigs shows that, at an early stage (5 h) after SM exposure, a marked increase occurred in epithelial nuclear vacuolation, epidermal thickening, and dermal acute inflammation. Topical iodine treatment reduced the severity of these parameters. The rate of DNA synthesis expressed by incorporation of bromodeoxyuridine was reduced upon topical treatment with iodine only or SM only by 46 and 72%, respectively. Iodine treatment following SM exposure exerted an effect similar to that of SM only, indicating that DNA synthesis is not directly involved in the mechanism of action of iodine-induced protection.
Previous studies have shown the antidotal efficacy of topical iodine at 15 and 30 min post-exposure to sulfur mustard (SM). Here we demonstrate efficacy at longer intervals (20, 30, 45, and 60 min, respectively, for data) using an improved topical povidone-iodine preparation termed N66, which contains steroidal and non-steroidal anti-inflammatory agents. In the mouse, N66 reduced severity of ear edema by 43, 47, 44, and 36%; ear epidermal ulceration by 74, 58, 45, and 58%; and epidermal necrosis by 54, 34, 26, and 31% at the respective time points. A similar effect was observed with encrustation. The healing marker, grade of acanthotic area, showed dramatic increases of 39.6-, 25.3-, 20.9-, and 22-fold. Severity of the dermal parameters, acute inflammation and dermal necrosis, was reduced by 63, 34, 34, and 38% and 80, 54, 54, and 59%, respectively. In guinea pig skin, topical treatment with N66 45 min post-exposure reduced the SM-induced ulceration area by 75%. The histological parameters subepidermal microblister formation, epidermal ulceration, epidermal necrosis, and encrustation were reduced by 63, 61, 41, and 41%, respectively. The healing marker, grade of acanthotic area, was elevated by 73%. N66 induced a statistically significant reduction in two dermal markers for tissue damage: acute inflammation (33%) and dermal necrosis (48%). Reduced skin damage was also observed in areas adjacent the treated sites. The pharmacologically active components of N66 showed additive effect. These findings suggest that the povidone-iodine preparation combined with anti-inflammatory agents functions as a potent antidote against skin lesions induced by SM at relatively long intervals between exposure and treatment.
Recently we have shown that post-exposure treatment with povidone iodine (PI) protects against nitrogen and sulfur mustard-induced skin lesions. Since proteolytic activity is involved in skin damage caused by chemical irritants, we have studied the effect of iodine on mechlorethamine (HN2)-induced skin collagenolytic activities in the haired guinea pig model. The matrix metalloproteinase-9 (MMP-9) activity increased by 30, 46, 12 and 23% after 3, 24, 48 and 72 h of HN2 exposure, respectively, whereas the MMP-2 was elevated by 8, 65, 8 and 30%, respectively. Topical treatment with PI at 15 and 120 min after HN2 exposure decreased the MMP-9 activity by 67% and 60%, respectively, when skin was analyzed 3 h after exposure. The same trend was observed in the MMP-2 and MMP-1 activities after PI treatment. A stronger effect of PI treatment 15 min following exposure was observed in skin analyzed 24 h after exposure, i.e. a decrease of 83% and 88% in MMP-9 and MMP-2 activities, respectively. Similar findings were observed with an interval of 120 min between HN2 exposure and PI treatment. A much weaker effect was observed on MMP-1 activity. A similar trend of PI-induced reduction in the three types of collagenase activity was found in skin analyzed 48 and 72 h after exposure. Reduced collagenolytic activity may serve as one of the mechanisms by which iodine protects the skin against chemical insult.
Sulfur mustard (SM, mustard gas) is a chemical warfare vesicant that rapidly penetrates the skin due to its hydrophobicity. This study measured the rate of SM disappearance from the skin after topical application of the vesicant. In both fur-covered and hairless animals, the remaining toxicant levels measured 60 min after exposure to undiluted SM were 0.6% and 0.3%, respectively, of the initially applied SM amount. However, SM concentration reached 0.4% of the initial dose 3 h following exposure in female fur-covered guinea pigs. SM quantities extracted from skin of male fur-covered and hairless guinea pigs immediately after 16 min of exposure to SM vapor were 12.2 and 21.8 µg, respectively; levels declined to 1.6 and 1.7 µg at 30 and 15 min following termination of exposure of male fur-covered and hairless guinea pigs, respectively. Three swabbing treatments of undiluted SM-exposed skin with gauze pads soaked in 0.5% hypochlorite caused 68% reduction in skin SM content. Similar findings were obtained when hypochlorite was replaced by water (64% reduction). SM content in the gauze pads was 59, 38 and 25 µg, respectively, for the first, second and third decontamination processes with water. No SM was detected in the gauze pads soaked with hypochlorite. In vitro studies showed that incubation of SM with 0.5% hypochlorite at a ratio of 10:1 (v/v) did not cause SM inactivation, whereas 4% hypochlorite reduced SM levels by 17%. However, at a decontaminant:SM ratio of 1000:1, 0.5% and 4% hypochlorite reduced SM levels by 92% and 99%, respectively. These findings are important for health authorities and regulatory agencies in planning precautionary steps to be taken in case of emergency and in routine laboratory work.
In a previous study we demonstrated the protective effect of topical iodine as postexposure treatment for sulfur mustard (SM) application. The iodine treatment results in significantly reduced inflammation and necrosis and increased epidermal hyperplasia. The expression and localization of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in paraffin-embedded skin samples from that study were evaluated in the present investigation. We compared the immunoreactivity of iNOS and COX-2 using five samples from each of the following four test sites: untreated control sites, SM-exposed sites, sites treated with iodine mixture 15 min after SM exposure, and sites treated with iodine 30 min after SM exposure. All animals were killed 2 days after irritant exposure. iNOS immunoreactivity was present only in skin sites exposed to SM without iodine treatment. The ulcerated skin was covered with a relatively thick band of exudate composed of iNOS-immunostained polymorphonuclear cells and macrophages. In untreated skin, COX-2 immunostaining was limited to the thin suprabasal epidermal layer. In SM-exposed skin, induction of COX-2 was noted in inflammatory cells located close to the site of epidermal injury. In skin sites treated with iodine 15 or 30 min after SM exposure, the regenerating hyperplastic epithelium showed moderate cytoplasmic staining localized to the epithelium overlying the basal layer. This pattern of staining was also present in the nearby dermal fibroblasts. Thus, in contrast to the skin samples exposed to SM without iodine treatment, the epidermal layer expressing immunohistochemical positivity for COX-2 was thicker and corresponded to the epidermal hyperplasia noted in samples treated with iodine. It is well documented that prostaglandins (PGs) promote epidermal proliferation, thereby contributing to the repair of injured skin. That the induction of the COX-2 shown in our study may also play a role in the healing process is indicated by the present evidence. The results suggest that nitric oxide radicals (NO .) are involved in mediating the damage induced by the SM and that iodine-related reduction in acute epidermal inflammation is associated with reduced iNOS expression.
Mustard gas (sulfur mustard, HD) is a powerful vesicant employed as a chemical weapon. The present study demonstrates the effect of povidone iodine (PI) ointment against skin toxicity caused by HD. Gross and histopathological examinations showed that application of PI 20 min or less following exposure to the vesicant resulted in marked skin protection. The shorter, interval between exposure and treatment, the better was the protection achieved. Povidone iodine was also effective against other mustards, such as carboxybutylchloroethyl sulfide (CBCS) and mechlorethamine. The fact that PI protected the skin against agents that cannot be oxidized, such as iodoacetic acid, divinylsulfone and cantharidine, indicated that the antidotal effect of PI was unrelated to oxidation of the nitrogen and sulfur atoms of the mustards. Furthermore, NMR spectroscopy of CBCS treated with iodine did not show oxidation of the sulfur atom. Clinical experience with patients after accidential heat burns (mostly of grade I) has shown that topical application of PI ointment immediately after the stimulus significantly reduced, and often prevented, skin lesions. Apart from being a safe and widely used disinfectant, PI ointment is recommended as an efficient protective agent against skin toxicity caused by hazardous chemicals and by heat stimuli.