Zearalenone induces oxidative stress and autophagy in goat Sertoli cells

Heme Oxygenase-1 Regulates Zearalenone-Induced Oxidative Stress and Apoptosis in Sheep Follicular Granulosa Cells

Zearalenone (ZEA) is a common non-steroidal estrogenic mycotoxin found in a range of animal feeds and poses a serious threat to the reproductive health of farm animals and humans. However, the mechanism underlying ZEA-induced reproductive toxicity in sheep remains unknown. Granulosa cells are crucial for egg maturation and the fertility of female sheep. In this study, we aimed to examine the impact of different ZEA concentrations on sheep follicular granulosa cells and to elucidate the potential molecular mechanism underlying ZEA-induced toxicity using transcriptome sequencing and molecular biological approaches. Treating primary sheep follicular granulosa cells with different concentrations of ZEA promoted the overproduction of reactive oxygen species (ROS), increased lipid peroxidation products, led to cellular oxidative stress, decreased antioxidant enzyme activities, and induced cell apoptosis. Using transcriptome approaches, 1395 differentially expressed genes were obtained from sheep follicular granulosa cells cultured in vitro after ZEA treatment. Among them, heme oxygenase-1 (HMOX1) was involved in 11 biological processes. The protein interaction network indicated interactions between HMOX1 and oxidative and apoptotic proteins. In addition, N-acetylcysteine pretreatment effectively reduced the ZEA-induced increase in the expression of HMOX1 and Caspase3 by eliminating ROS. Hence, we suggest that HMOX1 is a key differential gene involved in the regulation of ZEA-induced oxidative stress and apoptosis in follicular granulosa cells. These findings provide novel insights into the prevention and control of mycotoxins in livestock.

Effects of Reactive Oxygen and Nitrogen Species on Male Fertility

Significance: In recent decades, male fertility has been severely reduced worldwide. The causes underlying this decline are multifactorial, and include, among others, genetic alterations, changes in the microbiome, and the impact of environmental pollutants. Such factors can dysregulate the physiological levels of reactive species of oxygen (ROS) and nitrogen (RNS) in the patient, generating oxidative and nitrosative stress that impairs fertility. Recent Advances: Recent studies have delved into other factors involved in the dysregulation of ROS and RNS levels, such as diet, obesity, persistent infections, environmental pollutants, and gut microbiota, thus leading to new strategies to solve male fertility problems, such as consuming prebiotics to regulate gut flora or treating psychological conditions. Critical Issues: The pathways where ROS or RNS may be involved as modulators are still under investigation. Moreover, the extent to which treatments can rescue male infertility as well as whether they may have side effects remains, in most cases, to be elucidated. For example, it is known that prescription of antioxidants to treat nitrosative stress can alter sperm chromatin condensation, which makes DNA more exposed to ROS and RNS, and may thus affect fertilization and early embryo development. Future Directions: The involvement of extracellular vesicles, which might play a crucial role in cell communication during spermatogenesis and epididymal maturation, and the relevance of other factors such as sperm epigenetic signatures should be envisaged in the future.

Zearalenone Induces Blood-Testis Barrier Damage through Endoplasmic Reticulum Stress-Mediated Paraptosis of Sertoli Cells in Goats

Zearalenone (ZEA) is present worldwide as a serious contaminant of food and feed and causes male reproductive toxicity. The implication of paraptosis, which is a nonclassical paradigm of cell death, is unclear in ZEA-induced male reproductive disorders. In this study, the toxic effects of ZEA on the blood-testis barrier (BTB) and the related mechanisms of paraptosis were detected in goats. ZEA exposure, in vivo, caused a significant decrease in spermatozoon quality, the destruction of seminiferous tubules, and damage to the BTB integrity. Furthermore, ZEA exposure to Sertoli cells (SCs) in vitro showed similar dysfunction in structure and barrier function. Importantly, the formation of massive cytoplasmic vacuoles in ZEA-treated SCs corresponded to the highly swollen and dilative endoplasmic reticulum (ER), and paraptosis inhibition significantly alleviated ZEA-induced SC death and vacuolization, which indicated the important contribution of paraptosis in ZEA-induced BTB damage. Meanwhile, the expression of ER stress marker proteins was increased after ZEA treatment but decreased under the inhibition of paraptosis. The vacuole formation and SC death, induced by ZEA, were remarkably blocked by ER stress inhibition. In conclusion, these results facilitate the exploration of the mechanisms of the SC paraptosis involved in ZEA-induced BTB damage in goats.

A Cohort Study Investigating Zearalenone Concentrations and Selected Steroid Levels in Patients with Sigmoid Colorectal Cancer or Colorectal Cancer

THE AIM

In this study was to determine if sigmoid colorectal cancer (SCC) and colorectal cancer (CRC) in women (W) and men (M) is accompanied by zearalenone (ZEN) mycotoxicosis and changes in selected steroid levels.

MATERIALS AND METHODS

This cohort study was conducted on female and male patients selected from a population based on the presence of SCC or CRC, which was accompanied by the presence or absence (control group) of ZEN in their blood. The control group consisted of 17 patients with symptoms of SCC and CRC, where ZEN and its metabolites were not detected in the peripheral blood. The experimental groups comprised a total of 16 patients with SCC and CRC, where ZEN, but not its metabolites, was detected in their peripheral blood samples.

RESULTS

In groups SCC and CRC, the ZEN levels were very high, in the range from 214 to 289 ng/mL of blood. Considerable variations were observed in the concentrations of steroid hormones. Estradiol (E2) levels ranged from 166.25 (group C) to 325 pg/mL (group CRC) in women and from 98 (group C) to 95.5 pg/mL (group CRC) in men. Progesterone (P4) levels ranged from 12.09 (group C) to 13.64 ng/mL (group SCC) in women and from 6.98 (group CRC) to 12.01 ng/mL (group C) in men.

CONCLUSIONS

These results indicate that post-menopausal women and similarly aged elderly men have a high and individualized demand for estrogen that is relatively effectively met by ZEN, which triggers qualitative changes in estrogen receptors. The shortage of ZEN metabolites (values under the sensitivity of the method) confirmed the high estrogen demand in the studied subjects. The presence or absence of ZEN could have influenced the therapeutic outcomes in the analyzed patients.

chi-miR-130b-3p regulates the ZEA-induced oxidative stress damage through the KEAP1/NRF2 signaling pathway by targeting SESN2 in goat GCs

As a dominant mycotoxin, zearalenone (ZEA) has attracted extensive attention due to its estrogen-like effect and oxidative stress damage in cells. In order to find a way to relieve cell oxidative stress damage caused by ZEA, we treated goat granulosa cells (GCs) with ZEA and did a whole transcriptome sequencing. The results showed that the expression level of Sesterin2 (SESN2) was promoted extremely significantly in the ZEA group (p < .01). In addition, our research demonstrated that SESN2 could regulate oxidative stress level in GCs through Recombinant Kelch Like ECH Associated Protein 1 (KEAP1)/Nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway. The overexpression of SESN2 could reduce the oxidative damage, whereas knockdown of SESN2 would aggravate the oxidative damage caused by ZEA. What's more, microRNA (miRNA) chi-miR-130b-3p can bind to SESN2 3'-untranslated region (3'UTR) to regulate the expression of SESN2. The mimics/inhibition of chi-miR-130b-3p would have an effect on oxidative damage triggered by ZEA in GCs as well. In summary, these results elucidate a new pathway by which chi-miR-130b-3p affects the KEAP1/NRF2 pathway in GCs by modulating SESN2 expression in response to ZEA-induced oxidative stress damage.

Enhanced autophagy reversed aflatoxin B1-induced decrease in lactate secretion of dairy goat Sertoli cells

The deleterious effects of aflatoxins, especially aflatoxin B1 (AFB1) which are widespread at all stages of food production, on the reproductive system have been widely reported in males. However, it is still far from fully understood about the toxic effect and molecular mechanism after exposure to AFB1 in various testicular cells, especially Sertoli cells (SCs) which provide various energy materials and support to the developing germ cells as nurse cells. In this work, we examined the effects of AFB1 in dairy goat SCs on lactate production and autophagy, and the role of autophagy on AFB1-induced reduction in lactate production. Mechanistically, AFB1 destroyed the energy balance and reduced the secretion of lactate in dairy goat SCs (P < 0.01), resulting in a reduced level of ATP (P < 0.01) and phosphorylation of AMPK (P < 0.01). Subsequently, activated AMPK triggers autophagy by directly phosphorylating ULK1 (P < 0.05). The enhancement of autophagy partially reversed the AFB1-induced decrease in lactate secretion by promoting glucose utilization (P < 0.01) and increasing the expression of proteins related to lactate secretion in dairy goat SCs (P < 0.05) such as GLUT1, GLUT3, LDHA, and MCT4. Collectively, our study suggests that AFB1 inhibits the secretion of lactate which supply for germ cell development by damaging the "Warburg-like" metabolism of dairy goat SCs. Moreover, autophagy contributes to the resistance of glucose metabolism damage induced by AFB1. DATA AVAILABILITY: All data generated or analyzed in this study are available from the corresponding authors upon request.

Inhibition of Mitochondrial Fission Alleviates Zearalenone-Induced Mitochondria-Associated Endoplasmic Reticulum Membrane Dysfunction in Piglet Sertoli Cells

This study aimed to investigate the effects of zearalenone (ZEA) on piglet Sertoli cell (SC)-mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) based on mitochondrial fission, and to explore the molecular mechanism of ZEA-induced cell damage. After the SCs were exposed to the ZEA, the cell viability decreased, the Ca2+ levels increased, and the MAM showed structural damage. Moreover, glucose-regulated protein 75 (Grp75) and mitochondrial Rho-GTPase 1 (Miro1) were upregulated at the mRNA and protein levels. However, phosphofurin acidic cluster protein 2 (PACS2), mitofusin2 (Mfn2), voltage-dependent anion channel 1 (VDAC1), and inositol 1,4,5-trisphosphate receptor (IP3R) were downregulated at the mRNA and protein levels. A pretreatment with mitochondrial division inhibitor 1 (Mdivi-1) decreased the ZEA-induced cytotoxicity toward the SCs. In the ZEA + Mdivi-1 group, the cell viability increased, the Ca2+ levels decreased, the MAM damage was repaired, and the expression levels of Grp75 and Miro1 decreased, while those of PACS2, Mfn2, VDAC1, and IP3R increased compared with those in the ZEA-only group. Thus, ZEA causes MAM dysfunction in piglet SCs through mitochondrial fission, and mitochondria can regulate the ER via MAM.