Tebuconazole Induces ER-Stress-Mediated Cell Death in Bovine Mammary Epithelial Cell Lines

Abstract

Tebuconazole (TEB) is a triazole fungicide used to increase crop production by controlling fungi, insects, and weeds. Despite their extensive use, people are concerned about the health risks associated with pesticides and fungicides. Numerous studies have defined the cellular toxicity of triazole groups in pesticides, but the mechanisms of TEB toxicity in bovine mammary gland epithelial cells (MAC-T cells) have not yet been studied. Damage to the mammary glands of dairy cows directly affects milk production. This study investigated the toxicological effects of TEB on MAC-T cells. We found that TEB decreases both cell viability and proliferation and activates apoptotic cell death via the upregulation of pro-apoptotic proteins, such as cleaved caspases 3 and 8 and BAX. TEB also induced endoplasmic reticulum (ER) stress via the upregulation of Bip/GRP78; PDI; ATF4; CHOP; and ERO1-Lα. We found that TEB induced mitochondria-mediated apoptotic MAC-T cell death by activating ER stress. This cell damage eventually led to a dramatic reduction in the expression levels of the milk-protein-synthesis-related genes LGB; LALA; CSN1S1; CSN1S2; and CSNK in MAC-T cells. Our data suggest that the exposure of dairy cows to TEB may negatively affect milk production by damaging the mammary glands.

Potential Involvement of Oxidative Stress, Apoptosis and Proinflammation in Ipconazole-Induced Cytotoxicity in Human Endothelial-like Cells

“…It also increased caspase 3/7 activity in three human cell lines (HepG2, HEK293 and JEG3) at a concentration of 50 ppm [41]; in rat kidney cells, caspase 3/7 was induced at 175-200 µg/L [44]; and propiconazole in zebrafish increased caspase 3/7 activity by 1 µg/L [45]. Likewise, studies such as ours also found that triazole fungicides are able to alter the gene expression of te cell death biomarkers BAX, BCL2, BNIP3, APAF1 and AKT1 [37,43,[46][47][48][49].…”

“…Epoxiconazole was able to induce caspase 3 activity in F98 glioma cells at a concentration of 12-50 µM [25,34], in PC12 cells at a concentration of 5-20 µM [33] and in neural stem cells at a concentration of 2-10 µM [24]; in three human cell lines (HepG2, HEK293 and JEG3), caspase 3/7 was induced at a concentration of 125 g/L [41]. Tebuconazole increased caspase 9 and caspase 3 activation in myocardial cells at doses of 0.9, 9 and 27 mg/kg b. w. [42]; in bovine mammary gland epithelial cells at 100-200 µM [43]; in HCT116 cells at increasing doses of 12. 5, 25, 50 and 75 µM [40]; and in cardiac cells at concentrations of 30 and 60 µM [10].…”

Anticancer Effects of Mitoquinone via Cell Cycle Arrest and Apoptosis in Canine Mammary Gland Tumor Cells

“…Subsequently, cDNA was synthesized using MMLV reverse transcriptase (Thermo Fisher Scientific, Waltham, MA, USA), with the cDNA serving as a template for qPCR. The qPCR procedure and data analysis methods were consistent with our previous study [74]. The specific qPCR primer sequences are provided in Table 1.…”

“…Beyond cancer, the beneficial effects of MitoQ on various diseases have been previously documented, including the inhibition of prostatic hyperplasia via androgen receptor and NOD-like receptor family pyrin domain-containing 3 inhibition [68][69][70][71][72][73][74]. Additionally, MitoQ has successfully completed phase I safety and phase II clinical trials for diverse diseases, including Parkinson's disease and hepatitis C. Numerous studies have demonstrated that MitoQ provides protection against oxidative stress-induced conditions in both cell lines and animal disease models [39].…”

“…Cancer cell viability was assessed using a 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay with the EZ-Cytox Viability Assay Kit (Daeil Lab Services Co., Seoul, Republic of Korea, #EZ1000) following the manufacturer's instructions. The protocol described in previous studies [74,75] was followed. Briefly, both CMT-U27 and CF41.Mg cells were seeded in 96-well plates at a density of 3 × 10 3 cells/well in culture medium and incubated for 12 h. MitoQ (0-20 µM) was added to the cultured medium and incubated for 24 h. The reagent was then added to the plate as per the manufacturer's protocol and our previous study [76].…”