Embryonic caffeine exposure acts via A1 adenosine receptors to alter adult cardiac function and DNA methylation in mice

Evidence indicates that disruption of normal prenatal development influences an individual's risk of developing obesity and cardiovascular disease as an adult. Thus, understanding how in utero exposure to chemical agents leads to increased susceptibility to adult diseases is a critical health related issue. Our aim was to determine whether adenosine A1 receptors (A1ARs) mediate the long-term effects of in utero caffeine exposure on cardiac function and whether these long-term effects are the result of changes in DNA methylation patterns in adult hearts. Pregnant A1AR knockout mice were treated with caffeine (20 mg/kg) or vehicle (0.09% NaCl) i.p. at embryonic day 8.5. This caffeine treatment results in serum levels equivalent to the consumption of 2–4 cups of coffee in humans. After dams gave birth, offspring were examined at 8–10 weeks of age. A1AR+/+ offspring treated in utero with caffeine were 10% heavier than vehicle controls. Using echocardiography, we observed altered cardiac function and morphology in adult mice exposed to caffeine in utero. Caffeine treatment decreased cardiac output by 11% and increased left ventricular wall thickness by 29% during diastole. Using DNA methylation arrays, we identified altered DNA methylation patterns in A1AR+/+ caffeine treated hearts, including 7719 differentially methylated regions (DMRs) within the genome and an overall decrease in DNA methylation of 26%. Analysis of genes associated with DMRs revealed that many are associated with cardiac hypertrophy. These data demonstrate that A1ARs mediate in utero caffeine effects on cardiac function and growth and that caffeine exposure leads to changes in DNA methylation.

Hidden dangers in the kitchen: common foods toxic to dogs and cats

Many foods and food additives that are safe for human consumption can be extremely toxic to pets. Recognizing the clinical signs and clinicopathologic changes associated with these toxins allows prompt initiation of appropriate therapy. As with many other toxins, decontamination and supportive care are the mainstays of therapy for food toxicosis. Educating owners about foods and food additives that are unsafe for dogs and cats can help prevent toxicosis.

Using lysosomal membrane stability of haemocytes in Ruditapes philippinarum as a biomarker of cellular stress to assess contamination by caffeine, ibuprofen, carbamazepine and novobiocin

Although pharmaceuticals have been detected in the environment only in the range from ng/L to microg/L, it has been demonstrated that they can adversely affect the health status of aquatic organisms. Lysosomal membrane stability (LMS) has previously been applied as an indicator of cellular well-being to determine health status in bivalve mussels. The objective of this study is to evaluate LMS in Ruditapes philippinarum haemolymph using the neutral red retention assay (NRRA). Clams were exposed in laboratory conditions to caffeine (0.1, 5, 15, 50 microg/L), ibuprofen (0.1, 5, 10, 50 microg/L), carbamazepine and novobiocin (both at 0.1, 1, 10, 50 microg/L) for 35 days. Results show a dose-dependent effect of the pharmaceuticals. The neutral red retention time measured at the end of the bioassay was significantly reduced by 50% after exposure to environmental concentrations (p < 0.05) (caffeine = 15 microg/L; ibuprofen = 10 microg/L; carbamazepine = 1 microg/L and novobiocin = 1 microg/L), compared to controls. Clams exposed to these pharmaceuticals were considered to present a diminished health status (retention time < 45 min), significantly worse than controls (96 min) (p < 0.05). The predicted no environmental effect concentration (PNEC) results showed that these pharmaceuticals are very toxic at the environmental concentrations tested. Measurement of the alteration of LMS has been found to be a sensitive technique that enables evaluation of the health status of clams after exposure to pharmaceuticals under laboratory conditions, thus representing a robust Tier-1 screening biomarker.

Identification of biomarkers responsive to chronic exposure to pharmaceuticals in target tissues of Carcinus maenas

A 28-day bioassay was performed with Carcinus maenas to evaluate chronic effects caused by exposure to caffeine and ibuprofen (0.1-50 μg L(-1)) in sea water. Lysosomal membrane stability (LMS) was evaluated in hemolymph applying the neutral red retention assay (NRRA); several biomarkers including ethoxyresorufin O-deethylase (EROD), dibenzylfluorescein dealkylase (DBF), glutathione S-transferase (GST), glutathione peroxidase (GPX), lipid peroxidation (LPO) and DNA damage were studied in gill, hepatopancreas, muscle and gonad tissues. In crabs exposed to environmental concentrations of the drugs, retention time was reduced by 50%. EROD and DBFOD activities were induced by caffeine in muscle and hepatopancreas tissues (p < 0.05); GST activity was activated by ibuprofen in gill, hepatopancreas and muscle at the highest concentrations tested (p < 0.05). All tissues showed GPX activity and LPO induction (p < 0.05). Crabs exposed to caffeine and ibuprofen showed evidence of DNA damage mainly in hepatopancreas tissues (p < 0.05). Environmental concentrations of pharmaceuticals induce LMS and the biochemical responses studied in this crab. This methodology is a suitable technique for assessing pharmaceutical toxicity in the marine environment.

Chronic caffeine intake increases androgenic stimuli, epithelial cell proliferation and hyperplasia in rat ventral prostate

Coffee intake has been associated with a low risk of developing cancer, including prostate cancer, which is one of the most commonly diagnosed cancer in men. However, few studies have evaluated the chronic effects of caffeine, which is the most abundant methylxanthine in coffee, on prostate morphology and physiology. In the present study, we investigated the effects of chronic, low-dose caffeine intake on rat prostate morphology from puberty to adulthood. Five-week-old male Wistar rats were randomized into two experimental groups: caffeine-treated (20 ppm in drinking water, n = 12) and control (n = 12). The ventral and dorsolateral prostates were dissected, weighted and submitted to morphological, morphometrical and immunohistochemical analysis of cellular proliferation, apoptosis and androgen receptor (AR) tissue expression. The testosterone (T) and dihydrotestosterone (DHT) concentrations were measured in the plasma. Our results show that caffeine intake increased the concentrations of T and DHT, organ weight, epithelial cell proliferation and AR tissue expression in the ventral prostatic lobe. All the ventral prostates from the caffeine-treated animals presented various degrees of epithelial and stromal hyperplasia. Our results suggest that chronic caffeine intake from puberty increases androgenic signalling and cell proliferation in the rat prostate gland and can be related to the development of benign prostatic hyperplasia.

Distribution and temporal evolution of pharmaceutically active compounds alongside sewage sludge treatment. Risk assessment of sludge application onto soils

In this work, the distribution and the ecotoxicological risk of sixteen pharmaceutically active compounds belonging to seven different therapeutic groups (five anti-inflammatory drugs, two antibiotics, an anti-epileptic drug, a β-blocker, a nervous stimulant, four estrogens and two lipid regulators) have been studied in sewage sludge from wastewater treatment plants. Only three of the sixteen pharmaceutical compounds were never detected in sludge while eleven of the studied pharmaceuticals were still detected in compost. Mean concentration levels of the pharmaceutically active compounds ranged between 24.9 and 4105 μg/kg dm, 14.5-944 μg/kg dm, 3.29-636 μg/kg dm and 9.19-974 μg/kg dm in primary, secondary, digested sludge and compost, respectively. An increase in the concentration levels of most of the pharmaceuticals was observed from summer to winter (mean values in primary and secondary sludge were 304 and 85.1 μg/kg dm in summer and 435 and 175 μg/kg dm in winter, respectively) probably due to an increase of their consumption during the coldest season and a reduction of the microbial activity under colder temperatures. The highest ecotoxicological risk, in digested sludge and compost, was due to the estrogenic compound 17β-estradiol. The ecotoxicological risk significantly decreased after the application of digested sludge or compost to the soils (risk quotient values ranged between 0.04 and 252 in digested sludge and 0.002-37.8 in compost and decreased to 8·10(-4)-1.92 in digested sludge-amended soil and 1·10(-4)-0.23 in compost-amended soil).

Influence of caffeine on the survival of leaf-cutting ants Atta sexdens rubropilosa and in vitro growth of their mutualistic fungus

BACKGROUND

Leaf-cutting ants collect plant fresh material for the cultivation of their mutualistic fungus. Atta sexdens rubropilosa Forel (Hymenoptera: Formicidae) cause great economic losses through their foraging activity, mainly in agriculture. The main control method is the application of granulated toxic baits incorporated with an active ingredient (AI). The present goal is to evaluate the effect of caffeine on in vitro growth of the mutualistic fungus and on the survival of the leaf-cutting ants, aiming to verify the potential toxicity of this secondary metabolite over these organisms.

RESULTS

Three distinct patterns of fungal growth correlated with caffeine concentration were observed: (1) no effect (0.01% caffeine); (2) intermediate growth reduction (0.05% caffeine); (3) drastic growth reduction (0.10 and 0.50% caffeine). The highest caffeine concentration causes fungus death in the first week. As for insect survival, caffeine does not seem to exert any effect. The treatments with diet containing caffeine showed similar values of M50, irrespective of caffeine concentration.

CONCLUSION

As caffeine was shown to reduce growth of the mutualistic fungus of Atta sexdens rubropilosa, but with no conclusive effect on insect survival, a hypothetical explanation for the selection of different Coffea species by this leaf-cutting ant species might be associated with caffeine toxicity to the fungus.

Exploring the caffeine-induced teratogenicity on neurodevelopment using early chick embryo

Caffeine consumption is worldwide. It has been part of our diet for many centuries; indwelled in our foods, drinks, and medicines. It is often perceived as a "legal drug", and though it is known to have detrimental effects on our health, more specifically, disrupt the normal fetal development following excessive maternal intake, much ambiguity still surrounds the precise mechanisms and consequences of caffeine-induced toxicity. Here, we employed early chick embryos as a developmental model to assess the effects of caffeine on the development of the fetal nervous system. We found that administration of caffeine led to defective neural tube closures and expression of several abnormal morphological phenotypes, which included thickening of the cephalic mesenchymal tissues and scattering of somites. Immunocytochemistry of caffeine-treated embryos using neural crest cell markers also demonstrated uncharacteristic features; HNK1 labeled migratory crest cells exhibited an incontinuous dorsal-ventral migration trajectory, though Pax7 positive cells of the caffeine-treated groups were comparatively similar to the control. Furthermore, the number of neurons expressing neurofilament and the degree of neuronal branching were both significantly reduced following caffeine administration. The extent of these effects was dose-dependent. In conclusion, caffeine exposure can result in malformations of the neural tube and induce other teratogenic effects on neurodevelopment, although the exact mechanism of these effects requires further investigation.

Single and combined effects of selected pharmaceuticals at sublethal concentrations on multiple biomarkers in Carassius auratus

In this study, the sublethal effects of caffeine, sulfamethoxazole and their mixture on goldfish (Carassius auratus) were investigated, the biomarkers including acetylcholinesterase (AChE) in brain, 7-ethoxyresorufin O-deethylase (EROD), glutathione S-transferase (GST) and superoxide dismutase (SOD) in liver and vitellogenin (VTG) in serum were determined after 1, 2, 4, and 7 days of exposure. AChE activity was significantly inhibited by caffeine (≥0.4 mg/l), sulfamethoxazole (≥0.4 mg/l) and their mixtures (≥0.048 mg/l) during all exposure periods, and obvious concentration-response and time-response relationships were obtained. EROD, GST and SOD activities were significantly increased by individual compounds and mixtures in most cases. GST induction exhibited bell-shaped concentration-response curves. Serum VTG was significantly induced by 2 mg/l of caffeine, 10 mg/l of sulfamethoxazole and the mixtures at concentrations ≥1.2 mg/l. In general, the two pharmaceuticals induced similar biological responses. The joint effect of caffeine/sulfamethoxazole was additive with regard to AChE and GST activity variation and was antagonistic with regard to EROD and SOD induction. The results indicated that multiple biomarker response method might be a useful tool for describing an integrated toxicological effect of chemicals. VTG induction suggested that caffeine and sulfamethoxazole may cause a slightly feminization effect.

Molecular and microscopic assessment of the effects of caffeine, acetaminophen, diclofenac, and their mixtures on river biofilm communities

The authors examined effects of three common contaminants, caffeine (CF), acetaminophen (AC), and diclofenac (DF), as well as their mixtures on the development, functioning, and biodiversity of river biofilm communities. Biofilms were cultivated in rotating annular reactors. Treatments included AC, CF, DF, AC + CF, AC + DF, CF + DF, AC + CF + DF at 5 µg/L, and their molar equivalent as carbon and nutrients. Incubations using ¹⁴C-labeled AC, DF, and CF indicated that 90% of the CF, 80% of the AC, and less than 2% of the DF were converted to CO₂. Digital imaging revealed a variety of effects on algal, cyanobacterial, and bacterial biomass. Algal biomass was unaffected by AC or CF in combination with DF but significantly reduced by all other treatments. Cyanobacterial biomass was influenced only by the AC + DF application. All treatments other than AC resulted in a significant decrease in bacterial biomass. Diclofenac or DF + CF and DF + AC resulted in increases in micrometazoan grazing. The denaturing gradient gel electrophoresis of Eubacterial community DNA, evaluated by principal component analysis and analysis of similarity, indicated that relative to the control, all treatments had effects on microbial community structure (r = 0.47, p < 0.001). However, the AC + CF + DF treatment was not significantly different from its molar equivalent carbon and nutrient additions. The Archaeal community differed significantly in its response to these exposures based on community analyses, confirming a need to integrate these organisms into ecotoxicological studies.

[Isolation, extractive concentration, and determination of caffeine in the studies of blood plasma]

The optimal conditions for the isolation of caffeine from human blood by means of acetone extraction are described with special reference to the peculiarities of extraction from aqueous solutions. The possibility of concentration and purification of caffeine from blood plasma using acetone and aceton-chlorophorm mixture (2:8) as the solvents is illustrated. In addition, purification by silica-gel thin layer chromatography is discussed. Thin layer chromatography, UV-spectrophotometry, and high performance liquid chromatography are considered as potential methods for the identification and quantitative determination of caffeine.

Expression of HSP70 in Mytilus californianus following exposure to caffeine

Caffeine, a biologically active drug with many known molecular targets, is recognized as a contaminant of marine systems. Although the concentrations of caffeine reported from aquatic systems are low (ng/l-μg/l), harmful ecological effects not detected by traditional toxicity tests could occur as a result of caffeine contamination. We used Hsp70, a molecular biomarker of cellular stress, to investigate the sub-lethal cellular toxicity of environmentally relevant concentrations of caffeine on the mussel Mytilus californianus, a dominant species in the rocky intertidal zone along the Oregon Coast. Hsp70 concentrations in the gill and mantle tissue of mussels exposed to 0.05, 0.2, and 0.5 μg/l of caffeine for 10, 20, and 30 days were compared to basal levels in control mussels. Hsp70 in the gill tissue of M. californianus had an initial attenuation of the stress protein followed by a significant up-regulation relative to controls in all but the 0.5 μg/l treatment. Hsp70 in the mantle tissue of mussels exposed to caffeine did not differ from control mussels. This study provides laboratory evidence that environmentally relevant concentrations of caffeine can exert an effect on M. californianus gill tissue at the molecular-level.

Evaluation of the reproductive and developmental risks of caffeine

A risk analysis of in utero caffeine exposure is presented utilizing epidemiological studies and animal studies dealing with congenital malformation, pregnancy loss, and weight reduction. These effects are of interest to teratologists, because animal studies are useful in their evaluation. Many of the epidemiology studies did not evaluate the impact of the "pregnancy signal," which identifies healthy pregnancies and permits investigators to identify subjects with low pregnancy risks. The spontaneous abortion epidemiology studies were inconsistent and the majority did not consider the confounding introduced by not considering the pregnancy signal. The animal studies do not support the concept that caffeine is an abortafacient for the wide range of human caffeine exposures. Almost all the congenital malformation epidemiology studies were negative. Animal pharmacokinetic studies indicate that the teratogenic plasma level of caffeine has to reach or exceed 60 µg/ml, which is not attainable from ingesting large amounts of caffeine in foods and beverages. No epidemiological study described the "caffeine teratogenic syndrome." Six of the 17 recent epidemiology studies dealing with the risk of caffeine and fetal weight reduction were negative. Seven of the positive studies had growth reductions that were clinically insignificant and none of the studies cited the animal literature. Analysis of caffeine's reproductive toxicity considers reproducibility and plausibility of clinical, epidemiological, and animal data. Moderate or even high amounts of beverages and foods containing caffeine do not increase the risks of congenital malformations, miscarriage or growth retardation. Pharmacokinetic studies markedly improve the ability to perform the risk analyses.

Effect of melatonin and caffeine interaction on caffeine induced oxidative stress and sleep disorders

Effect of interaction of melatonin and caffeine on caffeine induced oxidative stress and sleep disorders was studied. Fifteen wistar rats were randomly assigned into three study groups. The animals in group 1 (the control) received a placebo of 10.0 ml distilled water via gastric intubation. The hosts in groups 2 and 3 were treated with 100 mg caffeine/ kg, or melatonin/ kg, respectively, in a total volume of 10.0 ml vehicle. The experiment lasted for 30 days. One day after the final exposure, the animals were euthanized by inhalation of overdose of chloroform. Blood was collected by cardiac puncture. Serum was obtained by centrifugation (6000 Xg, 30 mins), and used for serum total protein and serum blood urea nitrogen levels. The brain of each rat was also harvested and processed into whole homogenate, frozen in liquid nitrogen (N2), and maintained at -80oC until used for total brain cholesterol and tryptophan levels. The results showed that interaction of melatonin and caffeine enhanced protein synthesis; stimulated gonadotrophin release,  and could be used as oral contraceptive for women, and may be beneficial in the treatment of impotence (androgen depression), leading to improved reproductive and sex life; stimulated tryptophan metabolism, which prevents vitamin B6 deficiency, anemia, negative nitrogen balance, tissue wasting and accumulation of xanthurenic acid, which promotes sleep; and could be beneficial in the treatment of hyper cholesterolemia, thereby preventing coronary heart disease, and post menopausal osteoporosis.

Terrestrial short-term ecotoxicity of a green formicide

When ants become annoying, large quantities of formicide are applied to terrestrial ecosystems in tropical regions, but awareness of the health and environmental impacts related to the use of synthetic pesticides has been increasing. The use of green pesticides to combat target organisms could reduce these impacts. In this regard, terrestrial ecotoxicity tests with higher plants (Brassica olaracea, Lactuca sativa and Mucuna aterrima), annelids (Eisenia foetida), Collembola (Folsomia candida) and soil enzyme activity analysis (diacetate fluorescein hydrolysis) were used to evaluate short-term terrestrial ecotoxicity of a green pesticide prepared from naturally-occurring organic compounds. At the highest formicide concentration tested in these experiments (i.e., 50 g kg(-1) soil) no toxicity toward terrestrial organisms was observed. The lack of short-term terrestrial ecotoxicity suggest that this green formicide can be classed as an environmentally friendly product as compared to the ecotoxicity of the most commonly used commercialized formicides.

Degradation of fifteen emerging contaminants at microg L(-1) initial concentrations by mild solar photo-Fenton in MWTP effluents

The degradation of 15 emerging contaminants (ECs) at low concentrations in simulated and real effluent of municipal wastewater treatment plant with photo-Fenton at unchanged pH and Fe=5 mg L(-1) in a pilot-scale solar CPC reactor was studied. The degradation of those 15 compounds (Acetaminophen, Antipyrine, Atrazine, Caffeine, Carbamazepine, Diclofenac, Flumequine, Hydroxybiphenyl, Ibuprofen, Isoproturon, Ketorolac, Ofloxacin, Progesterone, Sulfamethoxazole and Triclosan), each with an initial concentration of 100 microg L(-1), was found to depend on the presence of CO(3)(2-) and HCO(3)(-) (hydroxyl radicals scavengers) and on the type of water (simulated water, simulated effluent wastewater and real effluent wastewater), but is relatively independent of pH, the type of acid used for release of hydroxyl radicals scavengers and the initial H(2)O(2) concentration used. Toxicity tests with Vibrio fisheri showed that degradation of the compounds in real effluent wastewater led to toxicity increase.

Chromosome shattering: a mitotic catastrophe due to chromosome condensation failure

Chromosome shattering has been described as a special form of mitotic catastrophe, which occurs in cells with unrepaired DNA damage. The shattered chromosome phenotype was detected after application of a methanol/acetic acid (MAA) fixation protocol routinely used for the preparation of metaphase spreads. The corresponding phenotype in the living cell and the mechanism leading to this mitotic catastrophe have remained speculative so far. In the present study, we used V79 Chinese hamster cells, stably transfected with histone H2BmRFP for live-cell observations, and induced generalized chromosome shattering (GCS) by the synergistic effect of UV irradiation and caffeine posttreatment. We demonstrate that GCS can be derived from abnormal mitotic cells with a parachute-like chromatin configuration (PALCC) consisting of a bulky chromatin mass and extended chromatin fibers that tether centromeres at a remote, yet normally shaped spindle apparatus. This result hints at a chromosome condensation failure, yielding a "shattered" chromosome complement after MAA fixation. Live mitotic cells with PALCCs proceeded to interphase within a period similar to normal mitotic cells but did not divide. Instead they formed cells with highly abnormal nuclear configurations subject to apoptosis after several hours. We propose a factor depletion model where a limited pool of proteins is involved both in DNA repair and chromatin condensation. Chromosome condensation failure occurs when this pool becomes depleted.

Safety assessment of heat-sterilized green tea catechin preparation: a 6-month repeat-dose study in rats

Evidence suggests that the purported health benefits associated with green tea consumption are related to tea catechins. In the present study, potential adverse effects of a standardized heat-sterilized green tea catechin (GTC-H) preparation was investigated following gavage administration to rats at doses of 0, 120, 400, 1200 mg/kg/day for 6 months. A decaffeinated high-dose group (1200 mg/kg/day) (GTC-HDC), was included for comparison. A possibly test article-related clinical finding of intermittent increased activity was noted in the 400 and 1200 mg/kg/day GTC-H groups, but was not considered to be adverse. Lower body weight gains without any decrease in food consumption were noted in the high-dose (1200 mg/kg/day)-treated GTC-H and GTC-HDC females. In the high-dose male GTC-H group, a lower total motor activity count for the 60-min session was noted prior to dosing at the study week 25 evaluations compared to the control group. Similar changes were not observed in the GTC-HDC group. Based on the results of this study, the no-observed-adverse-effect level (NOAEL) for GTC-H was 1200 mg/kg/day for males, the highest dose tested, and 400mg/kg/day for females based on reduced body weight gains. The NOAEL for GTC-HDC was 1200 mg/kg/day for males and could not be determined in females.

Proteomic assessment of caffeine effects on coral symbionts

Caffeine isthe mostwidely consumed and excreted psychoactive drug in the world. It is a ubiquitous tracer of urban wastewater, but its ecological effects are notwell understood. We hypothesized that caffeine exposure is associated with coral bleaching. Here we report the effects of caffeine on four species of coral algae endosymbionts belonging to three widely distributed clades: Clade A Symbiodinium microadriaticum (A), Clade B Symbiodinium sp. from Aiptasia pallida (B6), Clade B Symbiodinium sp. from Pseudoterogorgia bipinnata (B7), and Clade C Symbiodinium goreaui (C). To assess the effect of caffeine on algal physiology we used two-dimensional polyacrylamide gel electrophoresis and peptide mass spectrometry to identify protein sensitive to caffeine exposure. The results show several upregulated and several downregulated polypeptides in all algae species tested. The heat-shock proteins are among the commonly affected proteins, suggesting that caffeine exposure associated with sewage discharge into natural waters may exacerbate the effects of stress from other environmental factors such as changes in ocean temperature and pH.

Evaluation of the acute, chronic and teratogenic effects of a mixture of eleven pharmaceuticals on the cnidarian, Hydra attenuata

Pharmaceuticals have recently emerged as novel pollutants of potential concern in the aquatic environment where they are commonly introduced as complex mixtures via municipal effluent. In the present experiment, the freshwater cnidarian Hydra attenuata was exposed to a mixture of 11 pharmaceuticals (ibuprofen, naproxen, gemfibrozil, bezafibrate, carbamazepine, sulfapyridine, oxytetracycline, novobiocin, trimethoprim, sulfamethoxazole and caffeine) up to 10000 times (x) the concentration found in municipal effluent. Hydra regeneration and teratogenicity was measured, having an IC(50) of 781x and was found to be non teratogenic with an A/D value of approximately 1. Toxicity was investigated using both lethal (based on morphology) and sub-lethal (based on morphology, feeding behaviour, hydranth number and attachment) endpoints. The pharmaceutical mixture incurred a significant decrease in morphology at 0.1, 10 and 100x but a significant increase at 1000x. All parameters were significantly reduced at 10000x. An EC(50) of 425x and 65x based on morphology and feeding respectively and a toxicity threshold (TT) of 3.2x were calculated. When compared to the toxicity of each pharmaceutical exposed individually as previously reported [Quinn B, Gagné F, Blaise C. An investigation into the acute and chronic toxicity of eleven pharmaceuticals found in wastewater effluent on the cnidarian, H. attenuata. Sci Total Environ 2008a; 389: 306-314], the compounds in the mixture were present at concentrations 2 to 3 orders of magnitude lower for the equivalent toxicity (EC(50) and TT). These results indicate that pharmaceuticals act additively in a mixture, having sub-lethal effects at environmentally relevant (microg/L-ng/L) concentrations and that their combined concentrations could potentially prove significantly ecotoxic to Hydra and possibly to other aquatic taxa.

Pancreatic intraepithelial neoplasia and ductal adenocarcinoma induced by DMBA in mice: effects of alcohol and caffeine

PURPOSE

To evaluate the effects of alcohol and caffeine in a pancreatic carcinogenesis mouse model induced by 7,12-dimethylbenzantracene (DMBA), according to the PanIN classification system.

METHODS

120 male, Mus musculus, CF-1 mice were divided into four groups. Animals received either water or caffeine or alcohol or alcohol + caffeine in their drinking water. In all animals, 1 mg of DMBA was implanted into the head of the pancreas. After 30 days, euthanasia was performed; excised pancreata were then fixed in formalin, stained with hematoxylin-eosin and categorized as follows: normal ducts, reactive hyperplasia, PanIN-1A, PanIN-1B, PanIN-2, PanIN-3 or adenocarcinoma.

RESULTS

PanIN lesions were verified in all groups. Adenocarcinoma was detected in 15% of animals in the caffeine group, 16.6% in the water group, 23.8% in the alcohol + caffeine group and 52.9% in the alcohol group (P<0.05).

CONCLUSIONS

The experimental pancreatic carcinogenesis mouse model using DMBA effectively induces PanIN lesions and pancreatic adenocarcinoma. This study verified the association between alcohol use and pancreatic adenocarcinoma; caffeine did not present the same effect.

Quantitative measure of cytotoxicity of anticancer drugs and other agents

Many anticancer drugs act on cancer cells to promote apoptosis, which includes impairment of cellular respiration (mitochondrial O(2) consumption). Other agents also inhibit cellular respiration, sometimes irreversibly. To investigate the sensitivity of cancer cells to cytotoxins, including anticancer drugs, we compare the profiles of cellular O(2) consumption in the absence and presence of these agents. Oxygen measurements are made at 37 degrees C, using glucose as a substrate, with [O(2)] obtained from the phosphorescence decay rate of a palladium phosphor. The rate of respiration k is defined as -d[O(2)]/dt in a sealed container. Different toxins produce different profiles of impaired respiration, implying different mechanisms for the drug-induced mitochondrial dysfunction. The decrease in the average value of k over a fixed time period, I, is proposed as a characteristic value to assess mitochondrial injury. The value of I depends on the nature of the toxin, its concentration, and the exposure time as well as on the cell type. Results for several cell types and 10 cytotoxins are presented here.