| 1. |
- Buratovic, Sonja, 1986-, et al.
(författare)
-
Effects on adult cognitive function after neonatal exposure to clinically relevant doses of ionising radiation and ketamine in mice
- 2018
-
Ingår i: British Journal of Anaesthesia. - : ELSEVIER SCI LTD. - 0007-0912 .- 1471-6771. ; 120:3, s. 546-554
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Radiological methods for screening, diagnostics and therapy are frequently used in healthcare. In infants and children, anaesthesia/sedation is often used in these situations to relieve the patients' perception of stress or pain. Both ionising radiation (IR) and ketamine have been shown to induce developmental neurotoxic effects and this study aimed to identify the combined effects of these in a murine model. Methods: Male mice were exposed to a single dose of ketamine (7.5 mg kg(-1) body weight) s.c. on postnatal day 10. One hour after ketamine exposure, mice were whole body irradiated with 50-200 mGy gamma radiation (Cs-137). Behavioural observations were performed at 2, 4 and 5 months of age. At 6 months of age, cerebral cortex and hippocampus tissue were analysed for neuroprotein levels. Results: Animals co-exposed to IR and ketamine displayed significant (P <= 0.01) lack of habituation in the spontaneous behaviour test, when compared with controls and single agent exposed mice. In the Morris Water Maze test, co-exposed animals showed significant (P <= 0.05) impaired learning and memory capacity in both the spatial acquisition task and the relearning test compared with controls and single agent exposed mice. Furthermore, in co-exposed mice a significantly (P <= 0.05) elevated level of tau protein in cerebral cortex was observed. Single agent exposure did not cause any significant effects on the investigated endpoints. Conclusion: Co-exposure to IR and ketamine can aggravate developmental neurotoxic effects at doses where the single agent exposure does not impact on the measured variables. These findings show that estimation of risk after paediatric low-dose IR exposure, based upon radiation dose alone, may underestimate the consequences for this vulnerable population.
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
- Hallgren, Stefan, 1978-, et al.
(författare)
-
Adult dose-response-related behavioral effects of 4 different pesticides, after neonatal exposure
- 2014
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- There are several different types of pesticides globally used, all with their own characteristics and toxicological potency. In the present study we have exposed male mice neonatally to different doses of four different types of pesticides, carbaryl (carbamate) chlorpyrifos (organophosphate), cypermethrin (pyrethroid) and endosulfan (organochlorine), and tested them for spontaneous behavior in a novel home environment at adult age. The doses used were 0.5 – 20 mg carbaryl/kg bw, 0.1 – 5.0 mg chlorpyrifos/kg bw, 0.1 – 5.0 mg cypermethrin/kg bw and 0.05 – 20 mg endosulfan/kg bw. All four pesticides induced adult disturbances in the spontaneous behavior in a novel home environment, affecting cognitive function, at 2 months of age. Carbaryl induced a dose-response related effect on spontaneous behavior from 5 mg/kg bw and up, while chlorpyrifos only induced a weak effect with the highest dose tested (5 mg/kg bw). The pyrethroid cypermethrin induced dose-response related neurotoxicity from 0.5 mg/kg bw and up. The organochlorine endosulfan also induced dose-response related neurotoxicity from 0.1 mg/kg bw and up These disturbances also persisted when the animals were re-observed at 4 months of age, indicating that these effects are long-lasting or even irreversible. From this study we conclude that endosulfan seem to be the most potent, of these four compounds, to induce cognitive behavioral effects in the adult after neonatal exposure, while carbaryl has the lowest potency to induce these types of neurotoxic effects.
|
|
| 6. |
- Hallgren, Stefan, 1978-, et al.
(författare)
-
Postnatal exposure to PFOS, but not PBDE 99, disturb dopaminergic gene transcription in the mouse CNS
- 2016
-
Ingår i: Environmental Toxicology and Pharmacology. - : Elsevier BV. - 1382-6689 .- 1872-7077. ; 41, s. 121-126
-
Tidskriftsartikel (refereegranskat)abstract
- The CNS of breast feeding infants and toddlers may be exposed to persistent organic pollutants via lactational transfer. Here, 10 days old mice were exposed to single oral doses of either PFOS, PBDE99 or vehicle control and were examined for changes in dopaminergic gene transcription in CNS tissue collected at 24 h or 2 months post exposure.qPCR analyses of brain tissue from mice euthanized 24 h post exposure revealed that PFOS affected transcription of Dopamine receptor-D5 (DRD5) in cerebral cortex and Tyrosine hydroxylase (TH) in the hippocampus. At 2 months of age, mice neonatally exposed to PFOS displayed decreased transcription of Dopamine receptor-D2 (DRD2) and TH in hippocampus. No significant changes in any of the tested genes were observed in PBDE99 exposed mice. This indicates that PFOS, but not PBDE99, affects the developing cerebral dopaminergic system at gene transcriptional level in cortex and hippocampus, which may account for some of the mechanistic effects behind the aetiology of neuropsychiatric disorders.
|
|
| 7. |
|
|
| 8. |
- Lee, Iwa, et al.
(författare)
-
Developmental neurotoxic effects of two pesticides : behavior and biomolecular studies on chlorpyrifos and carbaryl
- 2015
-
Ingår i: Toxicology and Applied Pharmacology. - : Elsevier BV. - 0041-008X .- 1096-0333. ; 288:3, s. 429-438
-
Tidskriftsartikel (refereegranskat)abstract
- In recent times, an increased occurrence of neurodevelopmental disorders, such as neurodevelopmental delays and cognitive abnormalities has been recognized. Exposure to pesticides has been suspected to be a possible cause of these disorders, as these compounds target the nervous system of pests. Due to the similarities of brain development and composition, these pesticides may also be neurotoxic to humans. We studied two different pesticides, chlorpyrifos and carbaryl, which specifically inhibit acetylcholinesterase (AChE) in the nervous system. The aim of the study was to investigate if the pesticides can induce neurotoxic effects, when exposure occurs during a period of rapid brain growth and maturation. The results from the present study show that both compounds can affect protein levels in the developing brain and induce persistent adult behavior and cognitive impairments, in mice neonatally exposed to a single oral dose of chlorpyrifos (0.1, 1.0 or 5 mg/kg body weight) or carbaryl (0.5, 5.0 or 20.0 mg/kg body weight) on postnatal day 10. The results also indicate that the developmental neurotoxic effects induced are not related to the classical mechanism of acute cholinergic hyperstimulation, as the AChE inhibition level (8–12%) remained below the threshold for causing systemic toxicity. The neurotoxic effects are more likely caused by a disturbed neurodevelopment, as similar behavioral neurotoxic effects have been reported in studies with pesticides such as organochlorines, organophosphates, pyrethroids and POPs, when exposed during a critical window of neonatal brain development.
|
|
| 9. |
|
|
| 10. |
|
|
