Mitochondria are unique organelles to perform critical functions such as energy production, lipid oxidation, calcium homeostasis, and steroid hormone synthesis in eukaryotic cells. The proper functioning of mitochondria is crucial for cellular survival, homeostasis, and bioenergetics. Mitochondrial structure and function are maintained by the mitochondrial quality control system, which consists of the processes of mitochondrial biogenesis, mitochondrial dynamics (fusion/fission), mitophagy, and mitochondrial unfolded protein response UPRMT. Mitochondrial dysfunction and/or damage is associated with the initiation and progression of several human diseases, including neurodegenerative, cardiovascular, age-related diseases, diabetes, and cancer. Environmental stress and contaminants may exacerbate the sensitivity of mitochondria to damage which causes mitochondrial dysfunction. There is growing evidence about the impact of nanoplastics (NPs) and microplastics (MPs) on mitochondrial health and function. MPs/NPs were reported to trigger oxidative stress and reactive oxygen species production, which eventually change mitochondrial membrane potential. MPs/NPs can cross through the biological barriers in the human body and be internalized by the cells, potentially altering mitochondrial dynamics, bioenergetics, and signaling pathways, thus impacting cellular metabolism and function. This review states the effects of MPs/NPs on mitochondrial homeostasis and function as well as on mitochondrial membrane dynamics, mitophagy, and mitochondrial apoptosis are discussed.
To investigate the effects of di- n-hexyl phthalate (DHP) and dicyclohexyl phthalate (DCHP) on the development of fetus and placenta in utero, pregnant rats were exposed to DHP or DCHP at dosages of 0, 20, 100, and 500 mg/kg bw/day, by gavage, on gestational days 6–19. Anogenital distance (AGD) and AGD–body weight1/3 ratio of female fetuses decreased in all treatment groups in a non-dose–response way. The ossification centers of bones and the intensity of Alizarin red stain of the fetuses decreased in all treatment groups. The white blood cell levels of fetuses in DHP and DCHP exposed groups increased at all dosages. Mean cell hemoglobin, hemoglobin concentrations, and hemoglobin levels of all DHP and DCHP treated male and female fetuses were reduced. Histopathologic changes (hemorrhage in labyrinth, degeneration of spongiotrophoblast, hemorrhage, decreased and irregular vessel formation, and edema in the basal zone) were observed in placentas at high dosages of DHP and DCHP. In contrast, there was no change in weight gain of dams in DHP and DCHP exposed groups compared to control, but resorption rate, reduced fetal weight, delayed ossification, placental disruption, and hematologic parameters clearly indicated that in utero DHP and DCHP exposure resulted in intrauterine growth retardation in rats.
Phthalates are diester derivatives of phthalic acid widely used in many commercial applications. The aim of this study is therefore to evaluate possible genotoxicity of di- n-hexyl phthalate (DHP) and dicyclohexyl phthalate (DCHP) at different concentrations using single-cell gel electrophoresis (comet) and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end-labeling (TUNEL) assays in testes samples of male rat pups. DCHP and DHP in corn oil were administered to the pregnant rats by gavage at the doses of 0 (vehicle), 20, 100, and 500 mg kg−1 day−1 from gestational day 6 (GD6) to GD19. After delivery, male rats were allowed to grow until prepubertal, pubertal, and adulthood. At necropsy, the blood samples were collected from heart and were excised immediately. The apoptotic cells of prepubertal, pubertal, and adult testis were detected using TUNEL assay. The comet assay was performed on blood lymphocytes and testes samples of adult male rats. The comet assay results showed that tail length, tail intensity, olive tail moment (OTM), and percentage of DNA present in tail were higher when DHP content was increased. Judging from the values of OTM and percentage of DNA, DHP could significantly induce DNA breakage at doses of 100 and 500 mg kg−1 day−1 compared with the control group. An increase in TUNEL-positive cells of prepubertal, pubertal, and adult testicular cells was observed in the treated groups. In conclusion, prenatal exposure to DHP and DCHP may possess genotoxic risk to testicular cells of rats at all stages of development, even at adulthood.