Argemone oil induces genotoxicity in mice

Context: Argemone mexicana L. is native to Mexico and the plant extracts are used in traditional medicine in India and South American countries. Argemone oil (AO) is a common adulterant of mustard oil in India and causes serious pathophysiological consequences leading to outbreaks of epidemic dropsy among consumers. In vivo cytogenetic studies on the toxicological effects of AO and its component alkaloids are limited. Objective: The present study was undertaken to evaluate the safety of AO by assessment of their in vivo genotoxic potential in bone marrow cells of mice. Materials and methods: AO mixed in corn oil in the proportions of 0.01, 0.1, and 1?ml AO/kg body weight in a total volume of 10?ml/kg body weight and a single undiluted dose of AO (10?ml/kg body weight) were administered intraperitoneally in separate groups of male Swiss Albino mice for 24?h. In addition, a single concentration of sanguinarine (SG) (50?mg/kg body weight) was also administered. Genotoxicity was evaluated by chromosome aberration (CA) and sister chromatid exchange (SCE) tests. Bromodeoxyuridine (BrdU) differential technique was used to study the effect on cell replication by the calculation of average generation time (AGT). Results: The minimum effective concentrations that produced significant frequencies of CA and SCE were 0.1 and 0.01?ml/kg, respectively. AO and SG induced an insignificant increase of AGT indicating that they are non-cytotoxic in the concentrations tested.

Discussion and conclusion: Our results confirm that AO is genotoxic even at low concentrations and its usage should be checked.     

Assessing the risk of epidemic dropsy from black salve use

Epidemic dropsy is a potentially life‐threatening condition resulting from the ingestion of argemone oil derived from the seeds of Argemone mexicana Linn. Exposure to argemone oil is usually inadvertent, arising from mustard cooking oil adulteration. Sanguinarine, an alkaloid present in argemone oil, has been postulated as a causative agent with the severity of epidemic dropsy correlating with plasma sanguinarine levels. Cases of epidemic dropsy have also been reported following the topical application of argemone containing massage oil. Black salve, a topical skin cancer therapy also contains sanguinarine, but at significantly higher concentrations than that reported for contaminated massage oil. Although not reported to date, a theoretical risk therefore exists of black salve inducing epidemic dropsy. This literature review explores the presentation and pathophysiology of epidemic dropsy and assesses the risk of it being induced by black salve.     

Antioxidant status of erythrocytes and their response to oxidative challenge in humans with argemone oil poisoning

Oxidative damage of biomolecules and antioxidant status in erythrocytes of humans from an outbreak of argemone oil (AO) poisoning in Kannauj (India) and AO intoxicated experimental animals was investigated. Erythrocytes of the dropsy patients and AO treated rats were found to be more susceptible to 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) induced peroxidative stress. Significant decrease in RBC glutathione (GSH) levels (46, 63%) with concomitant enhancement in oxidized glutathione (172, 154%) levels was noticed in patients and AO intoxicated animals. Further, depletion of glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G-6-PDH) and glutathione-S-transferase (GST) (42-52%) was observed in dropsy patients. Oxidation of erythrocyte membrane lipids and proteins was increased (120-144%) in patients and AO treated animals (112-137%) along with 8-OHdG levels in whole blood (180%) of dropsy patients. A significant reduction in alpha-tocopherol content (68%) was noticed in erythrocytes of dropsy patients and hepatic, plasma and RBCs of AO treated rats (59-70%) thereby indicating the diminished antioxidant potential to scavenge free radicals or the limited transport of alpha-tocopherol from liver to RBCs leading to enhanced oxidation of lipids and proteins in erythrocytes. These studies implicate an important role of erythrocyte degradation in production of anemia and breathlessness in epidemic dropsy.     

Skin tumor promotion by argemone oil/alkaloid in mice: Evidence for enhanced cell proliferation,ornithine decarboxylase,cyclooxygenase-2 and activation of MAPK/NF-κB pathway

Consumption of argemone oil (AO) contaminated edible oil causes “Epidemic Dropsy”. Previously, we have shown that AO and isolated sanguinarine possess genotoxicity and skin tumor initiating activity. Here, we evaluate tumor-promoting potential of AO/sanguinarine alkaloid and investigate the molecular mechanisms involved therein. Single topical application of AO (50–400 μl/mouse) or sanguinarine alkaloid (1.5–12.0 μmol/mouse) afforded significant increase in (i) ornithine decarboxylase (ODC) activity, (ii) uptake of [³H]-thymidine in DNA, (iii) cyclooxygenase-2 (COX-2), proliferating cell nuclear antigen (PCNA) and ODC protein expressions, (iv) phosphorylation of extracellular signal-regulated kinase (ERK)1/2, c-jun-N-terminal kinase (JNK)1/2 and p38 mitogen-activated protein (MAP) kinases, (v) increased NF-κB activation and (vi) no significant increase in dark basal keratinocytes. Subsequently, when AO and sanguinarine alkaloid was tested either as complete or stage I or stage II tumor promoter in 7, 12-dimethyl benz(a)anthracene (DMBA)-initiated mice, there was enhanced tumor incidence, tumor body burden and higher % of mice with tumors, when AO (0.1 ml) or isolated sanguinarine (1.5 μmol) was tested as stage II tumor promoter. However, no tumors were found when AO or sanguinarine alkaloid was tested either as complete or stage I tumor promoter. These results indicate that AO/ sanguinarine alkaloid possesses tumor-promoting potential at stage II level involving MAPK/NF-κB pathway.     

In vivo DNA damaging potential of sanguinarine alkaloid, isolated from argemone oil, using alkaline Comet assay in mice.

Consumption of mustard oil contaminated with argemone oil is well known to cause clinical manifestation referred to as "Epidemic Dropsy". Our prior studies have shown that argemone oil produces genotoxic effects in mice [Ansari, K.M., et al., 2004. Int. J. Cancer 112, 890]. Since, sanguinarine alkaloid is the major component of argemone oil, the in vivo DNA damaging potential of the isolated alkaloid was investigated in blood and bone marrow cells of mice using alkaline Comet assay. Swiss albino male mice were given single intraperitoneal administration of 1.35, 2.70, 5.40, 10.80 and 21.60 mg sanguinarine alkaloid/kg b wt., while controls were treated with saline in the same manner. The results revealed a dose dependent increase in DNA damage in blood and bone marrow cells following 24 h treatment of sanguinarine alkaloid. All the three parameters of Comet assay including olive tail moment (OTM), tail length and tail DNA showed significant (p<0.05) increases in blood and bone marrow cells at respective doses of 10.80 and 5.40 mg alkaloid/kg b wt. However, some of the parameters were significantly increased even at lower doses of sanguinarine alkaloid (2.70 mg/kg b wt.). The frequency of cells exhibiting greater DNA damage were found to be increased by sanguinarine alkaloid in a concentration dependent manner. These results indicate that single exposure of sanguinarine alkaloid causes DNA damage in blood and bone marrow cells of mice, which could be responsible for the genotoxicity of argemone oil.     

Effect of argemone oil and argemone alkaloid,sanguinarine on Sertoli–germ cell coculture

Several incidences of reduction in the fertility (sperm count) have been reported in India and worldwide as well. Adulteration of food and consumption of adulterated mustard oil with argemone oil (AO) are presumed to be the factors for reduction in sperm count. In the present study we have studied the exfoliation of germ cells from Sertoli cell, its viability after detachment, cytotoxicity and execution of apoptosis via mitochondrial pathway for different concentration of AO, argemone alkaloid (AA) and its major constituent sanguinarine (SA). A dose dependent increase in germ cell detachment and decrease in viability of detached germ cells were observed (P < 0.05). A significant inhibition was observed via 3-(4,5-dimethylthiazol-2-yl)-2,5-dipehyl tetrazolium bromide (MTT) assay in the proliferative activity of germ cell and leakage of cytosolic enzyme was observed via Lactate dehydrogenase(LDH) assay (P < 0.05). A time and dose dependent inhibition of mitochondrial membrane potential was observed (P < 0.05). Treatment of Sertoli–germ cells with the lowest concentration of AO/AA and SA for 24 h resulted in 5.2- , 4.4- and 3.6-fold increase in the percentage of early apoptotic cells, respectively. This increase was enhanced to 8.3, 4.75 and 5.81-fold, respectively at 48 h in detached germ cells undergoing early apoptosis. These results suggest that alterations in germ cell apoptosis by a disruption in contact mediated communication between the Sertoli cells and germ cells, may subsequently lead to testicular impairment.     

Low doses of naloxone and MIF-1 peptides increases fluid consumption in rats

Three studies were done with albino rats to determine the effects of low doses of opiate antagonists on fluid intake. In Experiment 1, male rats were deprived of water for 12 hr and then randomly injected IP with 0.0, 0.01, 0.1, 1.0 or 10.0 mg/kg of naloxone. Ten min later they were given free access to a 20% sucrose solution and consumption was measured for the next 30 and 60 min on 2 consecutive days. Only animals injected with 1.0 or 10.0 mg/kg drank significantly less than controls. The other doses were not reliably different from controls but on Day 1 animals injected with 0.01 mg/kg of naloxone drank slightly more than controls. Experiment 2 followed the same procedure with lower doses of 0.0, 0.001, 0.01, and 0.1 mg/kg of naloxone. Although the effect of 0.1 mg/kg of naloxone was again not significant, this time animals injected with 0.001 and 0.01 mg/kg of naloxone consumed reliably more fluid than controls. Experiment 3 extended the findings to a peptide with opiate antagonistic properties and its analogs. Male and female rats were randomly assigned to receive an IP injection of 0.0, 0.01, 0.1, or 1.0 mg/kg of naloxone, MIF-1 (Pro-Leu-Gly-NH₂), the pGlu analog (pGlu-Leu-Gly-NH₂), or Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH₂). Measurement of intake occurred every 30 min or 600 min. Consumption was significantly increased. Rats injected with MIF-1 drank the most, followed in order by those injected with the pGlu analog, naloxone, Tyr-MIF-1, and controls. Dose was also reliable in a dose-dependent fashion, with animals receiving the lowest dose of 0.01 mg/kg drinking the most. None of the groups drank less than the controls. Sex was also significant in interactions with substance and dose. The results suggest that in some situations low doses of opiate antagonists may facilitate fluid consumption even though high doses are known to suppress the same behavior. The data also support the role of MIF-1 and MIF-1 analogs as opiate antagonists.     

Chemopreventive effects of mustard (Brassica compestris) on chemically induced tumorigenesis in murine forestomach and uterine cervix

As there is a strong correlation between diet and cancer, the dietary constituents that inhibit mutagenesis and/or carcinogenesis are of paramount importance for the prevention of human cancer. In the present study, cancer chemopreventive potentials of different doses of mustard (Brassica compestris) seed mixed diets were evaluated against benzo(a)pyrene [B(a)P]-induced forestomach tumorigenesis and 3-methylcholantrene (MCA)-induced uterine cervix tumorigenesis. Results showed a significant inhibition of stomach tumour burden (tumours/ mouse) by mustard seeds. Tumour burden was 7.08 +/- 2.47 in the B(a)P-treated control group, whereas it was reduced to 1.36 +/- 1.12 (P<0.001) by the 2.5% dose and 1.18 +/- 0.87 (P<0.001) by the 5% dose of mustard seeds. The cervical carcinoma incidence, as compared to MCA-treated control group (73.33%), was reduced to nil (P<0.05) by the 5% diet of mustard seeds and to 13.33% (P<0.05) by the 7.5% diet of mustard seeds. The effect of the 2.5% and 5% mustard seed mixed diets was also examined on the antioxidant enzymes, glutathione content, lactate dehydrogenase (LDH) and lipid peroxidation in the liver of Swiss albino mice. The glutathione-S-transferase-specific activity was increased (P<0.05) by the 2.5% dose, whereas there was no significant change in the activity of DT-diaphorase. In antioxidant systems, significant elevation of the specific activities of superoxide dismutase and catalase was observed with both doses of mustard seeds (P<0.05). The level of reduced glutathione (GSH) measured as nonprotein sulphydryl content was elevated by the 2.5% dose of mustard seeds only (P<0.05). Lipid peroxidation measured as formation of thiobarbituric acid reactive substances production showed significant inhibition (P<0.05) by the 5% dose of mustard seed mixed diet. LDH activity was decreased significantly (P<0.05) by both the doses. The results strongly suggest the cancer chemopreventive potentials of mustard seeds and their ability to enhance the antioxidant defence system and in turn provide protection against the toxic effects of carcinogens. It is likely that the use of mustard seeds in the diet may contribute to reducing the risk of cancer incidence and burden in the human population.     

Comparative dermal absorption of 2,3,7,8-tetrachlorodibenzo-p-dioxin and three polychlorinated dibenzofurans

Polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs) are toxic environmental contaminants which have the potential to accumulate in human tissues. In order to examine the potential for systemic exposure following dermal exposure, the absorption, distribution, and elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,7,8-tetrachlorodibenzofuran (TCDF), 1,2,3,7,8-pentachlorodibenzofuran (1PeCDF), and 2,3,4,7,8-pentachlorodibenzofuran (4PeCDF) were evaluated in male F344 rats. TCDD (0.00015, 0.001, 0.01, 0.1, 0.5, and 1.0 mumol/kg) and the three PCDFs (0.1, 0.5, and 1.0 mumol/kg) were applied to a preclipped region on the back of the rat and covered with a perforated cap. The rats were held in individual metabolism cages for 3 days. In animals administered 0.1 mumol/kg, the absorption of TCDF was greater than that of 4PeCDF, 1PeCDF, and TCDD. Relative absorption (percentage of administered dose) declined with increasing dose while the absolute absorption (microgram/kg) increased nonlinearly with dose. Absorption of TCDF at 0.1 mumol/kg was 48% of the administered dose which was significantly greater than that of the other compounds. At this dose, absorption of 4PeCDF was greater than that of TCDD. Absorption at the higher doses was similar for all four compounds. Maximum relative absorption of TCDD (approximately 40% of the administered dose) was obtained at 0.001 and 0.00015 mumol/kg. Major tissue depots for these four chemicals included liver, adipose, skin, and muscle tissue; however, the liver:fat ratio for 4PeCDF was approximately fourfold higher than that for the other three compounds. When normalized to 100% of dose absorbed, the distribution of 4PeCDF-derived radioactivity in liver and adipose tissue was similar to that previously observed after oral and iv administration. In animals administered 0.1 mumol TCDF or 1PeCDF/kg, 56 and 32% of the respective absorbed dose was excreted as polar metabolites within 3 days. Very little of the absorbed dose of either TCDD (approximately 10%) or 4PeCDF (approximately 2%) was eliminated. Results indicate that the dermal absorption of these compounds is incomplete and that systemic toxicity following acute dermal exposure to levels found in the environment is unlikely.     

Effects of androstenedione on in utero development in rats.

This study was conducted to characterize the effect of androstenedione on estrous cyclicity, mating behavior and fetal development. Thirty-day old rats received corn oil alone or androstenedione (in corn oil) at one of four concentrations (0, 1.0, 5.0, 10.0 or 30.0 mg/kg body weight) by gavage for two weeks prior to mating, during the mating period and throughout gestation. Dose related increases in serum androstenedione, estradiol and estrone were observed in all androstenedione treated animals at gestation day 20. A statistically significant increase in serum testosterone concentration was observed in the 30 mg/kg dose group. Feed and fluid consumption were not affected by androstenedione treatment during the pre-mating or gestational periods, however a statistically significant decrease in the number of females with regular estrous cycles was observed in the 10.0 and 30.0 mg/kg dose groups. Exposure to androstenedione did not affect mean body weight gain during pre-mating or gestation. Slight not statistically significant reductions in the number of implants, number of viable fetuses and number of viable male fetuses were observed in the 30.0 mg/kg androstenedione group. Reductions were not observed in the number of corpora lutea. Fetal growth in terms of fetal weight, crown-rump length, anogenital distance and the number of external abnormalities was not affected by androstenedione exposure. At the doses given, androstenedione had no specific effect on the development of individual bones, including sternebrae. Dose related effects of androstenedione were not observed on the development of soft tissues. A statistically significant increase in moderately enlarged ureter at the kidney was observed in both the 1.0 and 5.0 mg/kg dose groups. Organ weights (expressed per gram of body weight or per gram of brain weight) were not affected by androstenedione treatment.     

Dose-dependent metabolism and hepatic distribution of phenprocoumon in rats

The dose-dependency of phenprocoumon disposition was determined in rats by iv administration of 0.1 and 1.0 mg/kg doses to separate groups of animals. The intrinsic clearance (unbound clearance) was 33% lower in the animals given 1.0 mg/kg dose than in the animals given 0.1 mg/kg dose. The apparent unbound volume of distribution was 55% lower and the elimination rate constant 54% higher in the high dose group than in the lower dose group. Binding of phenprocoumon to liver showed saturability with a two- to threefold higher apparent unbound fraction of phenprocoumon in liver in animals given the high dose in comparison to animals given the low dose.     

Effects of succinylcholine on the recovery of block produced by mivacurium in rats

This study investigates the effects of succinylcholine on the recovery of neuromuscular blockade produced by mivacurium in rats. In 48 anesthetized animals, the sciatic nerve was prepared and stimulated, and twitches of the flexor digitorum longus muscle were recorded. Animals were randomly divided into four groups (n = 12 each): bolus dose of succinylcholine 0.1 mg/kg (GroupSch), bolus dose of mivacurium 0.15 mg/kg (GroupMiv), bolus dose of mivacurium 0.15 mg/kg, followed by succinylcholine 0.1 mg/kg at 25% neuromuscular recovery from mivacurium (Group-MivSch(25)), or bolus dose of mivacurium 0.15 mg/kg, followed by succinylcholine 0.1 mg/kg at 75% neuromuscular recovery from mivacurium (GroupMivSch(75)). Onset times of neuromuscular block following succinylcholine in mivacurium-treated groups were comparable and significantly shorter than in GroupSch (p < 0.001). Duration of action of succinylcholine was more prolonged when it was given in the presence of deeper neuromuscular block induced by mivacurium (p < 0.001 in GroupMivSch(25) and p < 0.01 in GroupMivSch(75)). Our results suggest that, in rats, mivacurium administration has a significant potentiating effect on a subsequent succinylcholine-induced neuromuscular block.     

Dose-dependent metabolism and hepatic distribution of phenprocoumon in rats

The dose-dependency of phenprocoumon disposition was determined in rats by iv administration of 0.1 and 1.0 mg/kg doses to separate groups of animals. The intrinsic clearance (unbound clearance) was 33% lower in the animals given 1.0 mg/kg dose than in the animals given 0.1 mg/kg dose. The apparent unbound volume of distribution was 55% lower and the elimination rate constant 54% higher in the high dose group than in the lower dose group. Binding of phenprocoumon to liver showed saturability with a two- to threefold higher apparent unbound fraction of phenprocoumon in liver in animals given the high dose in comparison to animals given the low dose.     

Enhancing effects of mustard oil on preneoplastic hepatic foci development in Wistar rats

Dietary habits are known to be the major contributory factor in the development of cancer. Mustard oil, which is extensively used in India and elsewhere as a flying and cooking medium, is reported to induce an inflammatory response. The development of altered hepatic foci is an early carcinogenic change in rat liver in diethylnitrosamine (DEN)-induced hepatocarcinogenesis. In the present study, the development of preneoplastic lesions was observed following administration of mustard oil (0.5 mL/day for 8 weeks) in DEN-initiated and partially hepatomized Wistar rats. A significant decrease in the relative and absolute liver weight of mustard oil-exposed rats was recorded. The results revealed a significant increase in the number and area of placental glutathione-S-transferase (GST-P) and gamma-glutamyl transpeptidase (GGT)-positive foci in mustard oil-administered animals. The GST-P- and GGT-positive foci were more prominent in the animals given boiled (up to 300 degrees C for 3 hours) mustard oil in comparison to the animals given fresh mustard oil. These results indicate the possible tumourigenic risk associated with mustard oil consumption.     

Chronic inhalation of carbon monoxide: effects on the respiratory and cardiovascular system at doses corresponding to tobacco smoking

Carbon monoxide (CO) is a dangerous poison in high concentrations, but the long-term effects of low doses of CO, as in the gaseous component of tobacco smoke, are not well known. The aims of our study were to evaluate the long-term effects of inhaled CO on the respiratory and cardiovascular system at doses corresponding to tobacco smoking and its effect on tumourigenesis and pulmonary neuroendocrine (NE) cells. Female Wistar rats were exposed to either CO (200 ppm) for 20 h/day (n=51) or air (n=26) for 72 weeks. Carboxyhaemoglobin was 14.7+/-0.3% in CO exposed animals and 0.3+/-0.1% in controls. In the lungs, no signs of pathology similar to that associated with cigarette smoking were observed, and no differences in number of pulmonary NE cells were observed between the groups. Chronic CO inhalation induced a 20% weight increase of the right ventricle (p=0.001) and a 14% weight increase of the left ventricle and interventricular septum (p<0.001). Histological examination of the myocardium did not reveal any signs of scarring. In the aorta and femoral artery, no signs of atherosclerosis were observed in CO exposed rats. No exposure related carcinogenic effects were observed. Spontaneous tumours were identified in 29% of CO exposed animals and in 28% of the controls. Our results suggest that low dose CO exposure is probably not responsible for the respiratory pathology associated with tobacco smoking. The effects on the cardiovascular system seem to involve myocardial hypertrophy, but not atherogenesis.     

The toxicity of brominated sesame oil and brominated soybean oil in miniature swine

Miniature swine were fed brominated sesame oil at dietary levels of 0, 5, 25, 50 or 500 mg/kg of body weight for 17 weeks and brominated soybean oil at levels of 0, 5, 50 or 500 mg/kg of body weight for 28 weeks. Growth rate and food intake were decreased only at the high dose level in the brominated sesame oil study. In both studies, signs of lethargy and ataxia occurred in pigs fed the highest dose, and were probably due to a dose-related increase in serum bromine concentrations. Marked elevations in lactic dehydrogenase (LDH), serum glutamic-oxalacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) values were seen at the highest dose level with both substances and these enzyme activities were increased at the 50 mg/kg dose level in the brominated sesame oil study. Histopathologic lesions were confined to animals given the highest dose level of either oil. Marked fatty degeneration of the hepatic plate cells and renal tubular epithelial cells were seen in both studies. In the brominated sesame oil study, neutral fat was moderately increased in the myocardium of the pigs fed 500 mg/kg. However, marked diffuse accumulation of LDH, marked diffuse fatty degeneration and focal degeneration, and/or necrosis of individual or small groups of cardiac muscle fibers were seen in the group fed brominated soybean oil at 500 mg/kg. A moderate to marked testicular atrophy was also observed in this group.A dose-related accumulation of total and hexane-soluble bromine was observed in all tissues examined in both studies; the highest concentrations occurred in adipose tissue of the pigs given the highest dose level. Kidneys, livers, hearts and thyroids of these groups also contained large amounts of bromine. In pigs given the 50 mg/kg dose level, total and hexane-soluble bromine concentrations were higher in the brominated sesame oil study than in the longer brominated soybean oil study and may be responsible for the elevations in LDH, SGPT and SGOT activities in this group.     

Pharmacokinetics of chlorambucil in patients with chronic lymphocytic leukaemia: comparison of different days, cycles and doses

The effects of repeated treatment cycles and different doses on intraindividual variation in oral bioavailability of chlorambucil and its first, active, and more toxic metabolite, phenylacetic acid mustard, were studied. Chlorambucil and phenylacetic acid mustard concentrations were measured with HPLC on Day 1 and on Day 4 in 15 timed blood samples from 11 chronic lymphocytic leukaemia patients receiving chlorambucil therapy cycles. Bioavailability was evaluated also after the first chlorambucil doses of six consecutive treatment cycles repeated every 4 weeks with increasing chlorambucil doses starting with 0.8 mg/kg/4 days, and increased by 0.1 mg/kg/4 days cycle. Area under the concentration-time-curve (AUC) from t=0 to infinite was in average 3.2 hr* microg/ml for the first cycle, and decreased by 17% in four days (P<0.05). The mean distribution half-life of chlorambucil was 0.49 hr and the terminal elimination half-life 2.45 hr. The bioavailability of chlorambucil decreased further when 4-day treatment cycles were repeated. For the fifth cycle, dose-corrected AUC for the first 2 hr was 33% smaller than that for the first cycle (P for trend <0.01). Data suggest accelerated metabolism and elimination of chlorambucil and phenylacetic acid mustard, but reduced oral bioavailability of chlorambucil cannot be excluded. However, except for AUC, none of the pharmacokinetic parameters of chlorambucil changed significantly during the first 4-day treatment period. The maximal plasma concentration and AUC of phenylacetic acid mustard did not change significantly during repeated treatment cycles. According to this trial a dose adjustment of chlorambucil is not necessary during a short-term course, but may be necessary when treatment cycles are repeated. An average increase in the chlorambucil dose of 10% per cycle maintains similar plasma concentration of chlorambucil.     

Granuloma pouch assay

Proliferation of granulation tissue on the inside of a subcutaneous (s.c.) air pocket was induced in rats by administration of 0.5 ml of 0.25% croton oil (granuloma pouch). Two days after induction of the granuloma, i.e., during the period of maximal cell growth, a single dose of 0.6 mg or 0.1 mg N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) was administered into the pouch. Fibrosarcomas of various histopathological types developed in 87% of the rats receiving the high dose and in 64% of the low dose animals. The mean latency period was 47.5 and 51.7 weeks respectively. Only one local sarcoma developed in rats treated with 0.6 mg MNNG by the s.c. route, and no tumors were observed in the groups treated with 0.1 mg s.c. The appearance of local sarcomas in the granuloma pouch tissue is correlated with previously reported frequency of point mutations (OUA^R and HGPRT⁻) induced in granuloma fibroblasts with the same doses of MNNG. Possible mechanisms explaining the marked enhancement of the carcinogenic effect of MNNG in the granuloma pouch assay are discussed.     

Efficacy of Aloe vera/olive oil cream versus betamethasone cream for chronic skin lesions following sulfur mustard exposure: a randomized double-blind clinical trial

Background: Chronic pruritic skin lesions are among the common late complications of sulfur mustard intoxication. In the present randomized double-blind clinical trial, therapeutic efficacy of Aloe vera/olive oil combination cream in the alleviation of these lesions was evaluated and compared to that of betamethasone 0.1% cream.

Methods: Sixty-seven Iranian chemical warfare-injured veterans were randomized to apply A. vera/olive oil (n?=?34, completers?=?31) or betamethasone 0.1% (n?=?33, completers?=?32) cream twice daily for 6 weeks. Evaluation of pruritus severity was performed using a pruritic score questionnaire and visual analogue scale (VAS).

Results: Both treatments were associated with significant reductions in the frequency of pruritus (p?<?0.05), burning sensation (p?<?0.01 and p?<?0.001 in A. vera/olive oil and betamethasone group, respectively), scaling (p?<?0.01 and p?<?0.05) and dry skin (p?<?0.001) at the end of trial. Fissure and excoriation were only reduced in the A. vera group (p?<?0.05). The change in the frequency of hyper- and hypopigmentation lesions, blisters, erythema and lichenification did not reach statistical significance in any of the groups (p?>?0.05). Mean pruritus (p?<?0.05) and VAS scores (p?<?0.01 and p?<?0.05) were significantly decreased by the end of trial in both groups. The rate of improvement in the pruritus severity [defined as being classified in a less severe category (mild, moderate and severe)] was found to be comparable between the groups (p?>?0.05).

Conclusion: A. vera/olive oil cream was at least as effective as betamethasone 0.1% in the treatment of sulfur mustard-induced chronic skin complications and might serve as a promising therapeutic option for the alleviation of symptoms in mustard gas-exposed patients.     

Andiroba oil (Carapa guianensis Aubl) shows cytotoxicity but no mutagenicity in the ACPP02 gastric cancer cell line

Andiroba (Carapa guianensis Aubl) is an Amazonian plant whose oil has been widely used in traditional medicine for various purposes, including anti-inflammation. Research reports indicate that the oil can confer antitumor activity due to the presence of fatty acids, which can directly influence cell death mechanisms. Thus, andiroba oil (AO) has gained interest for its potential to be used in antineoplastic therapies. Here, we report an in vitro analysis of the cytotoxic and mutagenic potential of AO in the gastric cancer cell line, ACP02. Cell survival was assessed by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, differential staining with ethidium bromide and acridine orange assessed apoptosis-necrosis, and mutagenesis was assessed by the micronucleus test. The apolar oil was first diluted in 0.1% dimethyl sulfoxide (DMSO) and then further diluted to six concentrations (0.01, 0.1, 1, 10 and 100 μg/mL and 1 mg/mL) in RPMI medium. Controls included RPMI alone (negative control) and 0.1% DMSO diluted in medium (vehicle control). The MTT test showed that AO significantly reduced cell viability (P < .05) only when the highest tested concentration was applied for 48 hours. The apoptosis/necrosis test showed that the highest concentration of AO induced cell death by apoptosis at 24 and 48 hours. There was no statistically significant increase in the frequency of micronuclei. The ability of the AO to decrease the viability of ACP02 cells via apoptosis, without exerting mutagenic effects, suggests that the oil could be useful as an alternative therapeutic agent for primary tumors of stomach cancer.