A permethrin/allethrin mixture induces genotoxicity and cytotoxicity in human peripheral blood lymphocytes.

Two pyrethroids, permethrin and allethrin, are often combined for large-scale use in public health programs to control vector-borne diseases. In this study, the genotoxic potential of a commercial formulation of permethrin and allethrin was examined using cultured human peripheral blood lymphocytes (PBL). Genotoxicity was evaluated using the cytokinesis-block micronucleus cytome (CBMN cyt) assay by measuring the frequency of micronuclei (MN), nuclear division index (NDI), formation of nucleoplasmic bridges (NPB) and nuclear buds (NBUD), as well as apoptotic and necrotic cells. Human PBL were treated with different concentrations of a permethrin/allethrin mixture (1/0.01, 5/0.07, and 10/0.14 µg/ml) for 24 or 36 h. The highest concentration (10/0.14 µg/ml) of permethrin/allethrin mixture significantly increased MN frequency and percent apoptotic cells after incubations for 24 or 36 h. The NDI was markedly decreased in response to treatment with 5/0.07 or 10/0.14 µg/ml permethrin/allethrin for both 24 and 36 h. Exposure to the permethrin/allethrin mixture did not significantly alter formation of NBUD, NPB, or percent necrotic cells. The MN frequency was significantly correlated with the number of apoptotic and necrotic cells but inversely correlated with NDI. Data demonstrated that a mixture of permethrin and allethrin induced concentration- and time-dependent cytotoxic and genotoxic damage to human PBL in vitro.

Serum Kynurenines Correlate With Depressive Symptoms and Disability in Poststroke Patients: A Cross-sectional Study.

BACKGROUND: Poststroke depression (PSD) is related to adverse functional and cognitive prognosis in stroke patients. The participation of kynurenine pathway metabolites in depression has been previously proposed; however, there are few studies on its role in PSD and disability in stroke. OBJECTIVE: To investigate if there is a correlation between serum kynurenines levels with poststroke anxiety and depression symptoms and disability scales. METHODS: A cross-sectional case-control study was conducted in patients with first stroke, of >1 month and <1 year of evolution, with no history of previous psychiatric or neurological disorders; the Hospital Anxiety and Depression Scale (HADS), Montreal Cognitive Assessment (MoCA), functional evaluations (Barthel index, Functional Independence Measure [FIM]) were applied and serum kynurenines (Kyns) were determined. RESULTS: Sixty patients were included; significant depressive symptoms were found in 63% of the cases; a significant and positive correlation was obtained between levels of 3-hydroxykynurenine (3-HK) with HADS-T (r = 0.30, P = .025) and HADS-D (r = 0.28, P = .039). Depressed patients showed significantly higher levels of 3HK (P = .048) and KYNA (P = .0271) than nondepressed patients; the 3HK levels were inversely correlated with functional scales: Barthel index (r = -0.31, P = .02), FIM (r = -0.40, P = .01); in addition, serum 3HK levels were significantly higher in patients with poor sleep quality (P = .0190). CONCLUSIONS: Serum Kyns show correlation with the presence and severity of depressive symptoms and with the disability and sleep quality. Kyns may be a potential marker of depression risk and disability in stroke in future.

Neurological effects of inorganic arsenic exposure: altered cysteine/glutamate transport, NMDA expression and spatial memory impairment.

Inorganic arsenic (iAs) is an important natural pollutant. Millions of individuals worldwide drink water with high levels of iAs. Chronic exposure to iAs has been associated with lower IQ and learning disabilities as well as memory impairment. iAs is methylated in tissues such as the brain generating mono and dimethylated species. iAs methylation requires cellular glutathione (GSH), which is the main antioxidant in the central nervous system (CNS). In humans, As species cross the placenta and are found in cord blood. A CD1 mouse model was used to investigate effects of gestational iAs exposure which can lead to oxidative damage, disrupted cysteine/glutamate transport and its putative impact in learning and memory. On postnatal days (PNDs) 1, 15 and 90, the expression of membrane transporters related to GSH synthesis and glutamate transport and toxicity, such as xCT, EAAC1, GLAST and GLT1, as well as LAT1, were analyzed. Also, the expression of the glutamate receptor N-methyl-D-aspartate (NMDAR) subunits NR2A and B as well as the presence of As species in cortex and hippocampus were investigated. On PND 90, an object location task was performed to associate exposure with memory impairment. Gestational exposure to iAs affected the expression of cysteine/glutamate transporters in cortex and hippocampus and induced a negative modulation of NMDAR NR2B subunit in the hippocampus. Behavioral tasks showed significant spatial memory impairment in males while the effect was marginal in females.