JNK and Jag1/Notch2 co-regulate CXCL16 to facilitate cypermethrin-induced kidney damage

Maternal exposure to beta-Cypermethrin disrupts placental development by dysfunction of trophoblast cells from oxidative stress

As a broad-spectrum and efficient insecticide, beta-Cypermethrin (β-CYP) poses a health risk to pregnancy. It matters the mechanisms of maternal exposure to β-CYP for impacting reproductive health. The placenta, a transient organ pivotal for maternal-fetal communication during pregnancy, plays a crucial role in embryonic development. The effect of β-CYP exposure on the placenta and its underlying molecular mechanisms remain obscure. The objective of this study was to investigate the effect of β-CYP exposure on placental development and the function of trophoblast, as well as the underlying mechanisms through CD-1 mouse model (1, 10, 20 mg/kg.bw) and in vitro HTR-8/SVneo cell model (12.5, 25, 50, 100 μM). We found slower weight gain and reduced uterine wet weight in pregnant mice with maternal exposure to β-CYP during pregnancy, as well as adverse pregnancy outcomes such as uterine bleeding and embryo resorption. The abnormal placental development in response to β-CYP was noticed, including imbalanced placental structure and disrupted labyrinthine vascular development. Trophoblasts, pivotal in placental development and vascular remodeling, displayed abnormal differentiation under β-CYP exposure. This aberration was characterized by thickened trophoblast layers in the labyrinthine zone, accompanied by mitochondrial and endoplasmic reticulum swelling within trophoblasts. Further researches on human chorionic trophoblast cell lines revealed that β-CYP exposure induced apoptosis in HTR-8/SVneo cells. This induction resulted in a notable decrease in migration and invasion abilities, coupled with oxidative stress and the inhibition of the Notch signaling pathway. N-acetylcysteine (an antioxidant) partially restored the impaired Notch signaling pathway in HTR-8/SVneo cells, and mitigated cellular functional damage attributed to β-CYP exposure. Collectively, exposure to β-CYP induced oxidative stress and then led to inhibition of the Notch signaling pathway and dysfunction of trophoblast cells, ultimately resulted in abnormal placenta and pregnancy. These findings indicate Reactive Oxygen Species as potential intervention targets to mitigate β-CYP toxicity. The comprehensive elucidation contributes to our understanding of β-CYP biosafety and offers an experimental basis for preventing and managing its reproductive toxicity.

The protective effect of caffeic acid phenethyl ester in the nephrotoxicity induced by α-cypermethrin

Alpha cypermethrin (α-CYP) is an insecticide, a member of the group of synthetic pyrethroid pesticides. This study aims to assess the histopathological and biochemical subacute effects of α-CYP on the renal tissues of 48 male Spraque-Dawley adult rats. In this study, the rats were divided into six groups: control, α-CYP (10 mg kg-1), α-CYP (20 mg kg-1), caffeic acid phenethyl ester (CAPE) (10 µmol kg-1), α-CYP + CAPE (10 mg kg-1), and α-CYP + CAPE (20 mg kg-1) groups. The percentage of weight gain was found to be dose-dependent on α-CYP in all groups. As a result of exposure, the normal histological structure of renal tissue was also observed in the control and CAPE groups, while glomerular atrophy and haemorrhage, enlargement of Bowman capsule, glomerular lobulation, and degeneration in distal and proximal tubules were noted in the α-CYP-treated groups with an increased frequency and severity in parallel with the dose increase. Although the severity and intensity of lesions decreased in the α-CYP + CAPE groups, they were statistically insignificant (p > 0.05). A decrease in the antioxidant parameter levels and an increase in oxidant parameters were observed in parallel with the negative effects of the antioxidant system in the α-CYP-treated groups. The groups exposed to CAPE in combination with α-CYP exhibited a therapeutic trend towards normalization in biochemical parameters due to the antioxidant character of CAPE. However, considering the statistical difference between the groups treated with α-CYP alone and CAPE alone, it was observed that the therapeutic features of those chemicals were not robust.

Deacetylation induced nuclear condensation of HP1γ promotes multiple myeloma drug resistance

Acquired chemoresistance to proteasome inhibitors is a major obstacle in managing multiple myeloma but key regulators and underlying mechanisms still remain to be explored. We find that high level of HP1γ is associated with low acetylation modification in the bortezomib-resistant myeloma cells using SILAC-based acetyl-proteomics assay, and higher HP1γ level is positively correlated with poorer outcomes in the clinic. Mechanistically, elevated HDAC1 in the bortezomib-resistant myeloma cells deacetylates HP1γ at lysine 5 and consequently alleviates the ubiquitin-mediated protein degradation, as well as the aberrant DNA repair capacity. HP1γ interacts with the MDC1 to induce DNA repair, and simultaneously the deacetylation modification and the interaction with MDC1 enhance the nuclear condensation of HP1γ protein and the chromatin accessibility of its target genes governing sensitivity to proteasome inhibitors, such as CD40, FOS and JUN. Thus, targeting HP1γ stability by using HDAC1 inhibitor re-sensitizes bortezomib-resistant myeloma cells to proteasome inhibitors treatment in vitro and in vivo. Our findings elucidate a previously unrecognized role of HP1γ in inducing drug resistance to proteasome inhibitors of myeloma cells and suggest that targeting HP1γ may be efficacious for overcoming drug resistance in refractory or relapsed multiple myeloma patients.

Evaluation of Toxic Effects Induced by Sub-Acute Exposure to Low Doses of α-Cypermethrin in Adult Male Rats

To contribute new information to the pyrethroid pesticide α-cypermethrin toxicity profile, we evaluated its effects after oral administration to Wistar rats at daily doses of 2.186, 0.015, 0.157, and 0.786 mg/kg bw for 28 days. Evaluations were performed using markers of oxidative stress, cholinesterase (ChE) activities, and levels of primary DNA damage in plasma/whole blood and liver, kidney, and brain tissue. Consecutive exposure to α-cypermethrin affected the kidney, liver, and brain weight of rats. A significant increase in concentration of the thiobarbituric acid reactive species was observed in the brain, accompanied by a significant increase in glutathione peroxidase (GPx) activity. An increase in GPx activity was also observed in the liver of all α-cypermethrin-treated groups, while GPx activity in the blood was significantly lower than in controls. A decrease in ChE activities was observed in the kidney and liver. Treatment with α-cypermethrin induced DNA damage in the studied cell types at almost all of the applied doses, indicating the highest susceptibility in the brain. The present study showed that, even at very low doses, exposure to α-cypermethrin exerts genotoxic effects and sets in motion the antioxidative mechanisms of cell defense, indicating the potential hazards posed by this insecticide.