MiR-214-3p promotes proliferation and inhibits estradiol synthesis in porcine granulosa cells

2,3,7,8-Tetrachlorodibenzo-p-Dioxin Suppresses Mesenchymal Cell Proliferation and Migration Through miR-214-3p in Cleft Palate

OBJECTIVE

The aetiology of CL/P is complicated, with both genetic and environmental factors. This study aimed to investigate the association between TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) exposure and changes in the expression of miR-214-3p in the context of cleft palate.

DESIGN

In this study, we established a fetal mouse cleft palate model using TCDD and differentially expressed miRNAs were analysed by microarray analysis and verified by qRT-PCR. Finally, we demonstrated the effects of TCDD and microRNAs on the proliferation and migration of mesenchymal cells by using CCK8, EDU, Transwell, and wound-healing assays.

RESULTS

Our findings revealed significant upregulation of miRNAs such as miR-214-3p, miR-296-5p, and miR-33-5p in the TCDD intervention group, while miRNAs like miR-92a-3p, miR-126a-3p, and miR-411-5p were significantly downregulated. Notably, qRT-PCR testing confirmed a significant difference in miR-214-3P expression. Further investigations involved the overexpression of miR-214-3p, reducing cell proliferation and migration in primary mouse embryonic palatal mesenchymal (MEPM) cells.

CONCLUSIONS

These results are consistent with the finding that TCDD suppresses palatal mesenchymal cell proliferation and migration through miR-214-3p. In conclusion, miR-214-3p probably plays a role in TCDD-induced cleft palates in mice.

Preliminary construction of non-coding RNAs and ceRNA regulatory networks mediated by exosomes in porcine follicular fluid

BACKGROUND

Follicles are fundamental units of the ovary, regulated intricately during development. Exosomes and ovarian granulosa cells (OGCs) play pivotal roles in follicular development, yet the regulatory mechanisms governing exosomes remain elusive.

RESULTS

High-throughput sequencing was employed to evaluate the complete transcript expression profiles of six samples (three porcine ovarian granulosa cells-exosome co-culture samples (GCE) and three porcine ovarian granulosa cells (POGCs) samples). Differential expression analysis revealed 924 lncRNAs, 35 circRNAs, 49 miRNAs, and 9823 mRNAs in the GCE group. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated enrichment of differentially expressed transcripts in pathways related to cell proliferation and apoptosis. Furthermore, a ceRNA regulatory network comprising 43 lncRNAs, 6 circRNAs, 11 miRNAs, and 126 mRNAs was constructed based on intergene co-expression correlations. Seven miRNAs associated with cell proliferation and apoptosis regulation were identified within this network, encompassing 92 subnet pairs as candidate genes for further exploration of exosome regulatory mechanisms. Additionally, preliminary verification at the cellular level demonstrated that exosomal miR-200b enhances the viability of POGCs.

CONCLUSIONS

Transcriptome analysis unveiled a pivotal candidate ceRNA network potentially implicated in exosome-mediated regulation of granulosa cell proliferation and apoptosis, thereby influencing porcine follicular development. These findings offer insights into the molecular mechanisms of follicular fluid exosome regulation, encompassing both coding and non-coding RNA perspectives.

MiR-223 inhibits proliferation and steroid hormone synthesis of ovarian granulosa cell via the AKT signaling pathway by targeting CRIM1 in chicken

Within the poultry industry, hens' reproductive performance is of great economic significance. The development and growth of follicles is a key aspect of hen egg production, and ovarian follicle growth and development are closely associated with granulosa cells (GCs) proliferation and the synthesis of steroid hormones. It has been confirmed by numerous studies that microRNAs (miRNAs) play important roles in the steroid hormone synthesis and proliferation of GCs. In this study, we examined the main miRNAs influencing hens' ability to reproduce, identified the miR-223 that is mainly expressed in atretic follicles based on sequencing, and investigated its role in GCs. Then, we used miR-223 mimic and inhibitor to knockdown or overexpress miR-223 expression. The result showed that miR-223 significantly inhibits both the steroid hormone synthesis and the proliferation of GCs. Subsequently, the results of the dual luciferase reporter experiment and bioinformatics prediction demonstrated that cysteine rich transmembrane BMP regulator 1 (CRIM1) was a downstream target gene of miR-223, and overexpression of miR-223 prevented CRIM1 expression. The function of CRIM1 was further investigated, and we observed a significant reduction in the synthesis of steroid hormones and the proliferation of GCs after transfection with CRIM1 siRNA. The opposite function of miR-223 was observed for CRIM1 in our study. Additionally, we demonstrated the involvement of the miR-223/CRIM1 axis in GCs through modulation of the AKT signaling pathway. Our data demonstrate the pivotal role of the miR-223 in the proliferation and steroid hormone synthesis of chicken GCs, which helps to explain how non-coding RNA (ncRNA) affects chicken reproductive function.

Hesperidin Alleviated Intestinal Barrier Injury, Mitochondrial Dysfunction, and Disorder of Endoplasmic Reticulum Mitochondria Contact Sites under Oxidative Stress

As primary flavonoids extracted from citrus fruits, hesperidin has been attracting attention widely for its capacity to act as antioxidants that are able to scavenge free radicals and reactive oxygen species (ROS). Many factors have made oxidative stress a risk factor for the occurrence of intestinal barrier injury, which is a serious health threat to human beings. However, little data are available regarding the underlying mechanism of hesperidin alleviating intestinal injury under oxidative stress. Recently, endoplasmic reticulum (ER) mitochondria contact sites (ERMCSs) have aroused increasing concerns among scholars, which participate in mitochondrial dynamics and Ca2+ transport. In our experiment, 24 piglets were randomly divided into 4 groups. Piglets in the diquat group and hesperidin + diquat group received an intraperitoneal injection of diquat (10 mg/kg), while piglets in the hesperidin group and hesperidin + diquat group received hesperidin (300 mg/kg) with feed. The results indicated that hesperidin alleviated growth restriction and intestinal barrier injury in piglets compared with the diquat group. Hesperidin ameliorated oxidative stress and restored antioxidant capacity under diquat exposure. The mitochondrial dysfunction was markedly alleviated via hesperidin versus diquat group. Meanwhile, hesperidin alleviated ER stress and downregulated the PERK pathway. Furthermore, hesperidin prevented the disorder of ERMCSs by downregulating the level of ERMCS proteins, decreasing the percentage of mitochondria with ERMCSs/total mitochondria and the ratio of ERMCSs length/mitochondrial perimeter. These results suggested hesperidin could alleviate ERMCS disorder and prevent mitochondrial dysfunction, which subsequently decreased ROS production and alleviated intestinal barrier injury of piglets under oxidative stress.

Hypoxia-Inducible Factor 1α Affects Yak Oocyte Maturation and Early Embryonic Development by Regulating Autophagy

In animal assisted reproductive technology, the production of high-quality oocytes is crucial. The yak, having lived in the Qinghai-Tibet Plateau for an extended period, has reproductive cells that are regulated by hypoxia-inducible factor 1α (HIF-1α). This study aimed to investigate the impact of HIF-1α on yak oocyte maturation and early embryonic development in vitro through the regulation of autophagy. The in vitro maturation process of yak oocytes involved the addition of the HIF-1α inducer DFOM and the inhibitor LW6 to examine their effects on yak oocyte maturation, early embryonic development, cell autophagy, cytochrome P450s (CYP450s) enzyme expression, and cumulus diffusion factors. The findings revealed that DFOM significantly upregulated the expression of HIF-1α, resulting in increased the cumulus diffusion area, elevated first polar body expulsion rate of oocytes, enhanced mitochondrial and actin levels, decreased ROS production, and reduced early apoptosis levels of oocytes. Moreover, DFOM promoted the expression of autophagy-related proteins, CYP450s enzymes, and cumulus diffusion factors, thereby enhancing oocyte maturation and early embryonic development. Conversely, LW6 exhibited opposite effects. The inhibition of autophagy levels with 3-MA during DFOM treatment yielded similar outcomes. Furthermore, reducing autophagy led to increased apoptosis levels at all stages of early embryonic development, as well as a significant decrease in total cell number and ICM/TE ratio of blastocysts. Studies have shown that during the in vitro maturation of yak oocytes, HIF-1α can affect the cumulus expansion area of oocytes by regulating autophagy, the first polar body excretion rate, mitochondrial level, actin level, ROS and early apoptosis level, the CYP450s enzyme, and the expression of cumulus expansion factors, thereby improving the in vitro maturation and early embryonic development of yak oocytes. These findings offer valuable insights into the reproductive regulation mechanism of yaks in hypoxic environments and suggest potential strategies for the advancement of yak assisted reproductive technology.

Mitochondria-associated endoplasmic reticulum membranes involve in oxidative stress-induced intestinal barrier injury and mitochondrial dysfunction under diquat exposing

Many factors induced by environmental toxicants have made oxidative stress a risk factor for the intestinal barrier injury and growth restriction, which is serious health threat for human and livestock and induces significant economic loss. It is well-known that diquat-induced oxidative stress is implicated in the intestinal barrier injury. Although some studies have shown that mitochondria are the primary target organelle of diquat, the underlying mechanism remains incompletely understood. Recently, mitochondria-associated endoplasmic reticulum membranes (MAMs) have aroused increasing concerns among scholars, which participate in mitochondrial dynamics and signal transduction. In this study, we investigated whether MAMs involved in intestinal barrier injury and mitochondrial dysfunction induced by diquat-induced oxidative stress in piglets and porcine intestinal epithelial cells (IPEC-J2 cells). The results showed that diquat induced growth restriction and impaired intestinal barrier. The mitochondrial reactive oxygen species (ROS) was increased and mitochondrial membrane potential was decreased following diquat exposure. The ultrastructure of mitochondria and MAMs was also disturbed. Meanwhile, diquat upregulated endoplasmic reticulum stress marker protein and activated PERK pathway. Furthermore, loosening MAMs alleviated intestinal barrier injury, decrease of antioxidant enzyme activity and mitochondrial dysfunction induced by diquat in IPEC-J2 cells, while tightening MAMs exacerbated diquat-induced mitochondrial dysfunction. These results suggested that MAMs may be associated with the intestinal barrier injury and mitochondrial dysfunction induced by diquat in the jejunum of piglets.

The novel circRNA circ_0045881 inhibits cell proliferation and invasion by targeting mir-214-3p in triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer (BC). The circRNA-miRNA‒mRNA axis is a promising biomarker for the early diagnosis and prognosis of BC. However, the critical circRNA mediators involved in TNBC progression and the underlying regulatory mechanism involved remain largely unclear.

METHODS

In this study, we carried out a circRNA microarray analysis of 6 TNBC patients and performed a gene ontology (GO) analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was used to characterize important circRNAs involved in TNBC progression. The interaction between circRNAs and miRNAs was determined by dual luciferase and RNA immunoprecipitation (RIP) assays. Moreover, Transwell, wound healing and Cell Counting Kit-8 (CCK8) assays were performed with altered circRNA or miRNA expression in MDA-MB-231 and BT-549 cells to investigate the roles of these genes in cell invasion, migration and proliferation.

RESULTS

A total of 78 circRNAs were differentially expressed in TNBC tissues, and the hsa_circ_0045881 level was significantly decreased in TNBC tissues and cells. Lentivirus-mediated hsa_circ_0045881 overexpression in MDA-MB-231 and BT-549 cells significantly reduced cell invasion and migration capacity. Additionally, hsa_circ_0045881 interacted with miR-214-3p in MDA-MB-231 cells. miR-214-3p mimics in MDA-MB-231 and BT-549 cells significantly enhanced cell invasion, migration and proliferation, but the other combinations of inhibitors had opposite effects on cell activity.

CONCLUSIONS

Our data indicated that the circRNA has_circ_0045881 plays key roles in TNBC progression and that hsa_circ_0045881 might act as a sponge for miR-214-3p to modulate its levels in TNBC cells, thereby regulating cell invasion, metastasis and proliferation. hsa_circ_004588 might be a potential prognostic marker and therapeutic target for TNBC.

miR-10a-5p inhibits steroid hormone synthesis in porcine granulosa cells by targeting CREB1 and inhibiting cholesterol metabolism

During growth, proliferation, differentiation, atresia, ovulation, and luteinization, the morphology and function of granulosa cells (GCs) change. Estrogen and progesterone are steroid hormones secreted by GCs that regulate the ovulation cycle of sows and help maintain pregnancy. miR-10a-5p is highly expressed in GCs and can inhibit GC proliferation. However, the role of miR-10a-5p in the steroid hormone synthesis of porcine GCs is unclear. In this study, miR-10a-5p agomir or antagomir was transfected into GCs. Overexpression of miR-10a-5p in GCs inhibited steroid hormone secretion and significantly downregulated steroid hormone synthesis via 3β-hydroxy steroid dehydrogenase and cytochrome P450 family 19 subfamily A member 1. Interference with miR-10a-5p had the opposite effect. Bodipy and Oil Red O staining showed that overexpression of miR-10a-5p significantly reduced the formation of lipid droplets. Overexpression significantly inhibited the content of total cholesterol esters in GCs. The mRNA and protein levels of 3-hydroxy-3-methylglutaryl-CoA reductase and scavenger receptor class B member 1 decreased significantly, and the opposite effects were seen by interference with miR-10a-5p. Bioinformatic analysis of potential targets identified cAMP-responsive element binding protein 1 as a potential target and dual-luciferase reporter system analysis confirmed that miR-10a-5p directly targets the 3' untranslated region. These findings suggest that miR-10a-5p inhibits the expression of 3β-hydroxy steroid dehydrogenase and cytochrome P450 family 19 subfamily A member 1 to inhibit the synthesis of steroid hormones in GCs. In addition, miR-10a-5p inhibits the cholesterol metabolism pathway of GCs to modulate steroid hormone synthesis.

Circ_TNFRSF21 promotes cSCC metastasis and M2 macrophage polarization via miR-214-3p/CHI3L1

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is a highly invasive disease with the potential to metastasize and cause fatality. Therefore, it is crucial to understand the mechanism behind cSCC in order to devise effective strategies to combat this disease.

OBJECTIVE

We investigated the function of circ_TNFRSF21/miR-214-3p/CHI3L1 axis in cSCC.

METHODS

The features of circ_TNFRSF21 was characterized using Sanger sequencing, and RNase R/actinomycin D treatment. Genes and M1/M2 markers levels were assessed by qRT-PCR and IHC. The proliferation, migration, and invasion of cells were evaluated by CCK-8, colony formation, EdU incorporation, and transwell assays. Tumor growth and metastasis in vivo were evaluated by nude mouse xenograft model. Interactions of circ_TNFRSF21/miR-214-3p and miR-214-3p/CHI3L1 were validated by RNA immunoprecipitation and dual luciferase assay.

RESULTS

Circ_TNFRSF21 and CHI3L1 expression were elevated in both human cSCC tissues and cells, whereas miR-214-3p was reduced. Circ_TNFRSF21 silencing or miR-214-3p overexpression suppressed cSCC cell proliferation, migration, invasion, and M2 macrophage polarization. Circ_TNFRSF21 functioned as a sponge for miR-214-3p while miR-214-3p directly targeted CHI3L1. Knockdown of miR-214-3p reversed the effects of circ_TNFRSF21 knockdown on cSCC development, while CHI3L1 upregulation reversed the effects of miR-214-3p overexpression. Furthermore, knockdown of circ_TNFRSF21 inhibited cSCC tumor growth and metastasis in vivo.

CONCLUSION

Circ_TNFRSF21 plays a significant role in cSCC progression by enhancing cell proliferation, migration, invasion, and M2 macrophage polarization through inhibiting miR-214-3p and subsequent disinhibition of CHI3L1. These findings deepen our understanding of the molecular mechanism of cSCC and propose the circ_TNFRSF21/miR-214-3p/CHI3L1 axis as promising diagnosis markers or therapeutic targets for cSCC.

Abnormal expression and role of MicroRNA-214-3p/SLC8A1 in neonatal Hypoxic-Ischaemic encephalopathy

Neonatal hypoxic-ischaemic encephalopathy (HIE) refers to brain damage caused by intra-uterine distress and asphyxia/hypoxia during the perinatal and neonatal periods. MicroRNA (MiR)-214-3p plays a critical role in cell growth and apoptosis. The aim of this study was to investigate the expression and role of miR-214-3p in neonatal HIE development, and to explore the underlying mechanisms. The expression of miR-214-3p was significantly down-regulated, while that of Slc8a1, a direct target of miR-214-3p, was significantly up-regulated, in the brain tissue of neonatal HIE rats. The over-expression of miR-214-3p promoted the proliferation and inhibited the apoptosis of neurones, while its down-regulation had the opposite effect. Our results indicate that miR-214-3p expression was down-regulated in neonatal HIE rats, and the up-regulation of miR-214-3p expression protected against HIE development by inhibiting neuronal apoptosis.

Mitochondrial function and E2 synthesis are impaired following alteration of CLOCK gene expression in porcine ovarian granulosa cells

Circadian locomotor output cycles kaput (CLOCK) is a critical component of the mammalian circadian clock system and regulates ovarian physiology. However, the functions and mechanisms of CLOCK in porcine granulosa cells (GCs) are poorly understood. The present study focused on CLOCK's effects on estradiol synthesis. Similarity analysis showed that CLOCK is highly conserved between pigs and other species. The phylogenetic tree analysis indicated that porcine CLOCK was most closely related to that in Arabian camels. CLOCK significantly reduced E₂ synthesis in GCs. CLOCK reduced the expression of steroidogenesis-related genes at the mRNA and protein levels, including CYP19A1, CYP11A1, and StAR. CYP17A1 levels were significantly downregulated. We demonstrated that CLOCK dramatically decreased ATP content, mitochondrial copy number, and mitochondrial membrane potential (MMP) and increased reactive oxygen species levels in GCs. We observed that mitochondria were severely damaged with fuzzy and fractured cristae and swollen matrix. These findings suggest that mitochondrial function and E₂ synthesis are impaired following the alteration of CLOCK gene expression in porcine ovarian GCs.

Interacting Networks of the Hypothalamic-Pituitary-Ovarian Axis Regulate Layer Hens Performance

Egg production is a vital biological and economic trait for poultry breeding. The 'hypothalamic-pituitary-ovarian (HPO) axis' determines the egg production, which affects the layer hens industry income. At the organism level, the HPO axis is influenced by the factors related to metabolic and nutritional status, environment, and genetics, whereas at the cellular and molecular levels, the HPO axis is influenced by the factors related to endocrine and metabolic regulation, cytokines, key genes, signaling pathways, post-transcriptional processing, and epigenetic modifications. MiRNAs and lncRNAs play a critical role in follicle selection and development, atresia, and ovulation in layer hens; in particular, miRNA is known to affect the development and atresia of follicles by regulating apoptosis and autophagy of granulosa cells. The current review elaborates on the regulation of the HPO axis and its role in the laying performance of hens at the organism, cellular, and molecular levels. In addition, this review provides an overview of the interactive network regulation mechanism of the HPO axis in layer hens, as well as comprehensive knowledge for successfully utilizing their genetic resources.

Totipotency of miR-184 in porcine granulosa cells

Estradiol (E₂) synthesis, cell proliferation and the apoptosis of porcine granulosa cells (GCs) affect follicular growth and development. The miR-184 level in ovary tissues of Yorkshire × Landrace sows was significantly higher in high-yielding sows than that in low-yielding sows, which was the same as in Yorkshire sows. However, the roles of miR-184 on E₂ granulosa cells (GCs) are still unclear. We found that miR-184 promoted E₂ synthesis and proliferation but inhibited apoptosis in GCs by targeting nuclear receptor subfamily 1 group D member 1 (NR1D1), cyclin dependent kinase inhibitor 1A (P21,CDKN1A) and homeodomain interacting protein kinase 2 (HIPK2) respectively. These findings indicated that miR-184 is a novel key factor that regulates the physiological functions of GCs.

gga-miR-449b-5p Regulates Steroid Hormone Synthesis in Laying Hen Ovarian Granulosa Cells by Targeting the IGF2BP3 Gene

MiRNAs have been found to be involved in the regulation of ovarian function as important post-transcriptional regulators, including regulators of follicular development, steroidogenesis, cell atresia, and even the development of ovarian cancer. In this study, we evaluated the regulatory role of gga-miR-449b-5p in follicular growth and steroid synthesis in ovarian granulosa cells (GCs) of laying hens through qRT-PCR, ELISAs, western blotting and dual-luciferase reporter assays, which have been described in our previous study. We demonstrated that gga-miR-449b-5p was widely expressed in granulosa and theca layers of the different-sized follicles, especially in the granulosa layer. The gga-miR-449b-5p had no significant effect on the proliferation of GCs, but could significantly regulate the expression of key steroidogenesis-related genes (StAR and CYP19A1) (p < 0.01) and the secretion of P4 and E2 (p < 0.01 and p < 0.05). Further research showed that gga-miR-449b-5p could target IGF2BP3 and downregulate the mRNA and protein expression of IGF2BP3 (p < 0.05). Therefore, this study suggests that gga-miR-449b-5p is a potent regulator of the synthesis of steroid hormones in GCs by targeting the expression of IGF2BP3 and may contribute to a better understanding of the role of functional miRNAs in laying hen ovarian development.

Fibroblast growth factor 21 (FGF21) promotes porcine granulosa cell estradiol production and proliferation via PI3K/AKT/mTOR signaling

The proliferation and steroidogenesis of mammalian ovarian granulosa cells (GCs) are related to follicular development. Previous studies found that fibroblast growth factor 21 (FGF21) regulated female fertility through the hypothalamic-pituitary-gonad axis. However, FGF21 receptors are expressed on GCs, so we speculate that it might affect female reproduction by regulating their physiological activities. Here, we showed that FGF21, fibroblast growth factor receptor-1(FGFR1), and beta-klotho (KLB) were expressed in porcine GCs. ELISA assays showed that estradiol (E₂) production was increased significantly when treating GCs with recombinant FGF21 (rFGF21). In addition, rFGF21 upregulated the mRNA and protein levels of E₂ synthesis-related genes including StAR, CYP11A1, and CYP19A1 in porcine GCs. Correspondingly, FGF21 siRNA inhibited E₂ levels and its synthesis-related gene expression. After rFGF21 treatment, CCK8 showed increased cell viability, and flow cytometry showed that the number of S phase increased, and cycle-related genes also increased. However, treatment with FGF21 siRNA to porcine GCs suppressed the cell cycle, viability, and EdU positive cell number. Consequently, FGF21/FGFR1/KLB forms a complex to activate the phosphatidylinositol-3-kinase (PI3K)/AKT/mTOR signaling pathway and further promote the proliferation and E₂ synthesis in porcine GCs. Collectively, these findings suggests that FGF21 regulates porcine ovarian folliculogenesis.

Lnc2300 is a cis-acting long noncoding RNA of CYP11A1 in ovarian granulosa cells

The high level of progesterone and 17β-estradiol ratio (P4/E2) in follicular fluid has been considered as a biomarker of follicular atresia. CYP11A1, the crucial gene encoding the rate-limiting enzyme for steroid hormone synthesis, has been reported differently expressed in the ovary during follicular atresia. However, the regulation mechanism of CYP11A1 expression during follicular atresia still remains unclear. Here, we have demonstrated that lnc2300, a novel pig ovary-specific highly expressed cis-acting long noncoding RNA (lncRNA) transcribed from chromosome 7, has the ability to induce the expression of CYP11A1 and inhibit the apoptosis of porcine granulosa cells (GCs). Mechanistically, lnc2300, mainly located in the cytoplasm of porcine GCs, sponges and suppresses the expression of miR-365-3p through acting as a competing endogenous RNA (ceRNA), which further relieves the inhibitory effects of miR-365-3p on the expression of CYP11A1. Besides, CYP11A1 is validated as a direct functional target of miR-365-3p in porcine GCs. Functionally, lnc2300 is an antiapoptotic lncRNA that reduces porcine GC apoptosis by inhibiting the proapoptotic function of miR-365-3p. In summary, our findings reveal a cis-acting regulation mechanism of CYP11A1 through lncRNA, and define a novel signaling pathway, lnc2300/miR-365-3p/CYP11A1 axis, which is involved in the regulation of GC apoptosis and follicular atresia.

Effects of Curcumin on Mitochondrial Function, Endoplasmic Reticulum Stress, and Mitochondria-Associated Endoplasmic Reticulum Membranes in the Jejunum of Oxidative Stress Piglets

Mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) are not only critical for the communication between two organelles but also crucial for cellular processes such as energy metabolism, calcium signaling, and mitochondrial dynamics. The effects of curcumin on jejunal mitochondria, ER, and MAMs in piglets under diquat-induced oxidative stress were assessed. Twenty-four piglets (35 days old, weaned at 21 days, 9.54 ± 0.28 kg, six piglets per group) were used in the study: (1) control group; (2) control + curcumin group; (3) diquat group; and (4) diquat + curcumin group. Curcumin was mixed with the basic diet at 200 mg/kg and fed to piglets. Piglets were administered intraperitoneally of 0.9% saline solution or diquat at 10 mg/kg body weight on the first day. Compared with the diquat group, curcumin improved jejunal morphology and barrier function. Meanwhile, curcumin improved mitochondrial function and ultrastructure, alleviated endoplasmic reticulum stress (ERS), and inhibited apoptosis induced by diquat. Moreover, curcumin prevented excessive MAM formation and alleviated MAM disorder. In conclusion, dietary curcumin ameliorated jejunal damage and mitochondrial dysfunction, attenuated ERS, and alleviated MAM disorder in oxidative stress piglets induced by diquat.

Bmal1 promotes prostaglandin E2 synthesis by upregulating Ptgs2 transcription in response to increasing estradiol levels in day 4 pregnant mice

Prostaglandin G/H synthase 2 (PTGS2) is a rate-limiting enzyme in prostaglandin synthesis. The present study assessed the role of the uterine circadian clock on Ptgs2 transcription in response to steroid hormones during early pregnancy. We demonstrated that the core clock genes (Bmal1, Per2, Nr1d1, and Dbp), Vegf, and Ptgs2, and their encoded proteins, have rhythmic expression in the mouse uterus from days 3.5 to 4.5 (D3.5-4.5) of pregnancy. Progesterone (P4) treatment of cultured uterus endometrial stromal cells (UESCs) isolated from mPer2Luciferase reporter gene knock-in mice on D4 induced a phase shift in PER2::LUCIFERASE oscillations. This P4-induced phase shift of PER2::LUCIFERASE oscillations was significantly attenuated by the P4 antagonist RU486. Additionally, the amplitude of PER2::LUCIFERASE oscillations was increased by estradiol (E2) treatment in the presence of P4. Consistently, the mRNA levels of clock genes (Bmal1 and Per2), Vegf, and Ptgs2 were markedly increased by E2 treatment of UESCs in the presence of P4. Treatment with E2 also promoted prostaglandin E2 (PGE2) synthesis by UESCs. Depletion of Bmal1 in UESCs by small-interfering RNA (siRNA) decreased the transcript levels of clock genes (Nr1d1 and Dbp), Vegf, and Ptgs2 compared with nonsilencing siRNA treatment. Bmal1 knockdown also inhibited PGE2 synthesis. Moreover, the mRNA expression levels of clock genes (Nr1d1 and Dbp), Vegf, and Ptgs2, and their respective proteins were significantly decreased in the uterus of Bmal1-/- mice. Thus, these data suggest that Bmal1 in mice promotes PGE2 synthesis by upregulating Ptgs2 in response to increases in E2 on D4 of pregnancy.NEW & NOTEWORTHY Rhythmic expression of Bmal1 and Ptgs2 was observed in the uterus isolated from D3.5-4.5 of pregnant mice. E2 increased the expression of Bmal1 and Ptg2 in UESCs isolated from mice on D4. The expression of Ptgs2 was significantly decreased in Bmal1-siRNA treated UESCs. Bmal1 knockdown also inhibited PGE2 synthesis. Thus, these data suggest that Bmal1 in mice promotes PGE2 synthesis by upregulating Ptgs2 in response to increases in E2 on D4 of pregnancy.

Estrogen disorders: Interpreting the abnormal regulation of aromatase in granulosa cells (Review)

Ovarian granulosa cells (GCs) are the most important source of estrogen. Therefore, aromatase (estrogen synthase), which is the key enzyme in estrogen synthesis, is not only an important factor of ovarian development, but also the key to estrogen secretion by GCs. Disorders of the ovarian estrogen secretion are more likely to induce female estrogen-dependent diseases and fertility issues, such as ovarian cancer and polycystic ovary syndrome. Hence, aromatase is an important drug target; treatment with its inhibitors in estrogen-dependent diseases has attracted increasing attention. The present review article focuses on the regulation and mechanism of the aromatase activity in the GCs, as well as the specific regulation of aromatase promoters. In GCs, follicle-stimulating hormone (FSH) is dependent on the cyclic adenosine monophosphate (cAMP) pathway to regulate the aromatase activity, and the regulation of this enzyme is related to the activation of signaling pathways, such as phosphatidylinositol 3-kinase (PI3K) and extracellular signal-regulated kinase (ERK). In addition, endocrine-disrupting substance and other related factors affect the expression of aromatase, which eventually create an imbalance in the estrogen secretion by the target tissues. The present review highlights these useful factors as potential inhibitors for target therapy.

Circadian clock gene BMAL1 controls testosterone production by regulating steroidogenesis-related gene transcription in goat Leydig cells

Testosterone is produced by Leydig cells (LCs) and undergoes diurnal changes in serum levels in rats, mice, and humans, but little is known in goats. The present study revealed that goat serum testosterone levels displayed diurnal rhythmic changes (peak time at ZT11.2). Immunohistochemical staining showed that BMAL1, a circadian clock protein, is highly expressed in goat LCs. ELISA revealed that both hCG (0-5 IU/ml) and 22R-OH-cholesterol (0-30 μM) addition stimulated testosterone synthesis in primary goat LCs in a dose-dependent manner. Treating goat LCs with hCG (5 IU/ml) significantly increased intracellular cAMP levels. Additionally, real-time quantitative polymerase chain reaction (PCR) analysis revealed that the circadian clock (BMAL1, PER1, PER2, DBP, and NR1D1) and steroidogenesis-related genes (SF1, NUR77, StAR, HSD3B2, CYP17A1, CYP11A1, and HSD17B3) showed rhythmic expression patterns in goat LCs following dexamethasone synchronization. Several Bmal1-Luc circadian oscillations were clearly observed in dexamethasone-treated goat LCs transfected with the pLV6-Bmal1-Luc plasmid. BMAL1 knockdown significantly downregulated mRNA levels of PER2, NR1D1, DBP, StAR, HSD3B2, SF1, NUR77, and GATA4, and dramatically decreased StAR and HSD3B2 protein levels and testosterone production. In contrast, BMAL1 overexpression significantly increased the mRNA and protein expression levels of StAR and HSD17B3 and enhanced testosterone production. Reporter assays revealed that goat BMAL1, or in combination with mouse CLOCK, activated goat HSD17B3 transcription in vitro. These data indicate that BMAL1 contributes to testosterone production by regulating transcription of steroidogenesis-related genes in goat LCs, providing a basis for further exploring the underlying mechanism by which the circadian clock regulates ruminant reproductive capability.