PI3K, AKT, and P-AKT levels in thin endometrium

Comprehensive review of the traditional uses and the potential benefits of epimedium folium

Epimedium Folium has been extensively utilized for medicinal purposes in China for a significant period. This review undertakes a comprehensive examination of literature pertaining to Epimedium and its metabolites over the past decade, drawing from databases such as PubMed. Through meticulous organization and synthesis of pertinent research findings, including disease models, pharmacological effects, and related aspects, this narrative review sheds light on the principal pharmacological activities and associated mechanisms of Epimedium in safeguarding the reproductive system, promoting bone health, mitigating inflammation, and combating tumors and viral infections. Consequently, this review contributes to a more profound comprehension of the recent advances in Epimedium research.

PI3K/AKT signaling alters glucose metabolism in uterine microenvironment of women with idiopathic recurrent spontaneous miscarriage

BACKGROUND

This study aims to identify metabolomic signatures in uterine fluid of women with idiopathic recurrent spontaneous miscarriage (IRSM) during window of implantation (WOI). Also, glucose transporters GLUT3 and GLUT4 and proteins of PI3K-Akt signaling pathway in endometrial tissue are assessed.

METHODS

Paired uterine fluid and endometrial biopsies were collected during WOI from women with IRSM (n = 24) and healthy women with azoospermic male partners as controls (n = 15). NMR metabolomics was used to identify the dysregulated metabolites in uterine fluid of IRSM women. Additionally, proteins and glucose transporters were investigated in the endometrial tissue using immunohistochemistry (IHC) and western blotting.

RESULTS

Uterine fluid metabolomics indicated eleven metabolites to be significantly downregulated in IRSM. While expression levels of PI3K (p85), PI3K (p110), p-Akt (Thr308), p-Akt (Ser473), GLUT3 and GLUT4 were significantly downregulated in endometrial tissue of these women, p-IKK α/β (Ser176/180) and p-NFkBp65 (Ser536) were significantly increased.

CONCLUSION

Our findings suggest that dysregulation of PI3K/Akt pathway in the uterine microenvironment could be a likely cause of endometrial dysfunction, thereby affecting implantation. Further studies on the downstream effects of the Akt signaling pathway in-vitro for improved understanding of the Akt-mediated cellular responses in IRSM is, therefore, warranted.

Gene pathway analysis of the endometrium at the start of the window of implantation in women with unexplained infertility and unexplained recurrent pregnancy loss: is unexplained recurrent pregnancy loss a subset of unexplained infertility?

This study aims to understand differences/similarities in the genetic profile of the endometrium at the start of window of implantation (WOI) in women with unexplained infertility (UI) and unexplained recurrent pregnancy loss (uRPL). Differentially expressed genes (DEGs) from the endometrium were evaluated using gene expression array and pathway enrichment analysis was performed to analyse gene expression pathways involved in both conditions. We found 2,171 genes arranged in 117 pathways and 730 genes arranged in 33 pathways differentially expressed in endometrium of patients in UI and uRPL, respectively. Complement-coagulation cascades, morphine addiction pathway, and PI3K-Akt signalling pathway were predominantly differentially expressed in UI. Cancer pathways, NF-κB signalling pathway, and actin cytoskeleton regulation pathway showed significant changes in uRPL. Forty-eight percent of DEGs and 84% of differentially expressed pathways in uRPL were found in the endometrium of UI patients. Unexpected close association in gene expression pathways between UI and uRPL is observed supporting the hypothesis 'uRPL is a clinical subset of UI'. Yet 100% DEGs overlap wasn't found suggesting the endometrium has still some different gene expression patterns at start of WOI in UI and uRPL. Lastly, diagnostic tools may be developed for uRPL because more specific genes-pathways are involved compared with UI, which shows broader genetic expression profile.

Effect of AKT silence on malignant biological behavior of renal cell carcinoma cells

BACKGROUND

As the most common malignant tumor of primary renal tumor, renal cell carcinoma (RCC) is the highly invasive disease with high mortality. AKT is a serine/threonine kinase that play a critical role in the phosphoinositide 3-kinase (PI3K) signaling pathway, and it is an attractive target for RCC treatment. The aim of present study was to investigate the effect of AKT silence on malignant behavior of renal cell carcinoma cells.

METHODS

AKT expression was quantified by immunohistochemistry in tumor tissues and normal tissues. The human RCC cell lines Caki-2 cell were chosen for this study. The optimal silencing siRNA was subsequently selected by RT-qPCR and western blot. The effect of AKT silence on RCC cells was investigated by CCK8 assay, transwell assay, scratch test and flow cytometry. The AKT1 expression in human renal cell carcinoma tissue was detected by immunohistochemical staining.

RESULTS

The AKT in Caki-2 cells was silenced successfully. The results shown AKT silence could inhibit cell proliferation, invasion, and, migration. In addition, AKT silence could promote Caki-2 cell apoptosis with prevention of RCC cells move from G1 phase to S phase. Immunohistochemical staining revealed significant difference of expression of AKT1 in RCC tissues and normal renal tissues. Taken together, AKT family members might involve in malignant growth of RCC, and might be a potential therapeutic target.

CONCLUSION

Our data show that AKT silence inhibited cell proliferation, invasion, and, migration of Caki-2 cell, and promoted Caki-2 cell apoptosis. Moreover, AKT silence prevented RCC cells move from G1 phase to S phase. Therefore, AKT may act as an effective therapeutic target for RCC.

The expressions of matrix metalloproteinase-9, estrogen receptor, and progesterone receptor in thin endometrial tissue and their significance

OBJECTIVE

This study aims to investigate the expressions of matrix metalloproteinase-9 (MMP-9), estrogen receptor (ER), and progesterone receptor (PR) in thin endometrium.

METHODS

Patients who received treatment in our hospital between January 2018 and September 2020 were enrolled. Endometrial thickness was measured using transvaginal ultrasound; in patients with a midluteal phase endometrial thickness of <7 mm, a sample of endometrial tissue was obtained using a hysteroscope, and the MMP-9, ER, and PR expressions were detected using immunohistochemistry. In addition, the number of endometrial glands was calculated in a complete field of view under a low-power (100×) microscope, and the serum estrogen and progesterone levels were determined. Following hormone therapy, the midluteal phase endometrial thickness was measured again using transvaginal ultrasound, and the patients were divided into two groups: the thin endometrium group and the normal endometrium group (n = 50, each). Patients in the thin endometrium group had an endometrial thickness of <7 mm, while patients in the normal endometrium group had an endometrial thickness of 7-10 mm.

RESULTS

The number of endometrial glands as well as the ER and MMP-9 expressions were lower in the thin endometrium group than in the normal endometrium group; the differences were statistically significant (p < .05). The receiver operator characteristic curve revealed that ER and MMP-9 had a high prediction accuracy in patients with refractory thin endometrium, while the number of endometrial glands was moderately predictive.

CONCLUSION

Compared with other patients with thin endometrium, patients with refractory thin endometrium had a reduced the number of endometrial glands and significantly lower ER and MMP-9 expressions.

Down-regulation of PBK inhibits proliferation of human endometrial stromal cells in thin endometrium

BACKGROUND

Thin endometrium (TE) is a challenging clinical issue in the reproductive medicine characterized by inadequate endometrial thickness, poor response to estrogen and no effective treatments currently. At present, the precise pathogenesis of thin endometria remains to be elucidated. We aimed to explore the related molecular mechanism of TE by comparing the transcriptome profiles of late-proliferative phase endometria between TE and matched controls.

METHODS

We performed a bulk RNA-Seq (RNA-sequencing) of endometrial tissues in the late-proliferative phase in 7 TE and 7 matched controls for the first time. Differential gene expression analysis, gene ontology enrichment analysis and protein-protein interactions (PPIs) network analysis were performed. Immunohistochemistry was used for molecular expression and localization in endometria. Human endometrial stromal cells (HESCs) were isolated and cultured for verifying the functions of hub gene.

RESULTS

Integrative data mining of our RNA-seq data in endometria revealed that most genes related to cell division and cell cycle were significantly inhibited, while inflammation activation, immune response and reactive oxygen species associated genes were upregulated in TE. PBK was identified as a hub of PPIs network, and its expression level was decreased by 2.43-fold in endometria of TE patients, particularly reduced in the stromal cells, which was paralleled by the decreased expression of Ki67. In vitro experiments showed that the depletion of PBK reduced the proliferation of HESCs by 50% and increased the apoptosis of HESCs by 1 time, meanwhile PBK expression was inhibited by oxidative stress (reduced by 76.2%), hypoxia (reduced by 51.9%) and inflammatory factors (reduced by approximately 50%). These results suggested that the insufficient expression of PBK was involved in the poor endometrial thickness in TE.

CONCLUSIONS

The endometrial transcriptome in late-proliferative phase showed suppressed cell proliferation in women with thin endometria and decreased expression of PBK in human endometrial stromal cells (HESCs), to which inflammation and reactive oxygen species contributed.

Integrated Transcriptomic Analysis of the miRNA-mRNA Interaction Network in Thin Endometrium

Although the thin endometrium (TE) has been widely recognized as a critical factor in implantation failure, the contribution of miRNA-mRNA regulatory network to the development of disease etiology remains to be further elucidated. This study performed an integrative analysis of the miRNA-mRNA expression profiles in the thin and adjacent normal endometrium of eight patients with intrauterine adhesion to construct the transcriptomic regulatory networks. A total of 1,093 differentially expressed genes (DEGs) and 72 differentially expressed miRNAs (DEMs) were identified in the thin adhesive endometrium of the TE group compared with the control adjacent normal endometrial cells. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses showed that the DEGs and the target genes of DEM were significantly enriched in angiogenesis, cell growth regulation, and Wnt signaling pathway. Multiple hub genes (CAV1, MET, MAL2, has-mir-138, ARHGAP6, CLIC4, RRAS, AGFG1, has-mir-200, and has-mir-429) were identified by constructing the miRNA-mRNA regulatory networks. Furthermore, a miRNA-mRNA pathway function analysis was conducted, and the hub genes were enriched in the FoxO signaling pathway, cell growth regulation, inflammatory response regulation, and regulation of autophagy pathways. Our study is the first to perform integrated mRNA-seq and miRNA-seq analyses in the thin adhesive endometrium and the control adjacent normal endometrial cells. This study provides new insights into the molecular mechanisms underlying the formation of thin endometrium.

Effects of phosphorylated estrogen receptor alpha on apoptosis in human endometrial epithelial cells

It is known that the activities of estrogen receptor α (ERα) can be modulated by epidermal growth factor (EGF) through the phosphatidylinostitol 3-kinase-alpha serine/threonine protein kinase (PI3K-AKT) pathway by phosphorylation. To clarify how ERα functions are regulated in endometrial cells during menstrual cycle, molecules related to phosphorylation of ERα (pERα) were examined. It was found that the expression of phosphorylated AKT on serine 473 (pAKT-Ser473) was increased during the proliferative phase, but decreased in the secretory phase. Although the expression of pAKT on threonine 308 in the proliferative phase was only identified in the wall of arterioles, it was strongly expressed in the cytoplasm of endometrial glandular cells after entering the secretory phase. Further observations revealed that while the expression of pERα-Ser104 was constant, pERα-Ser118 was expressed following a cyclic pattern similar to that of the pAKT-Ser473. Following treatment with specific inhibitors for EGFR-PI3K-AKT pathway, it was found that while the expression of pERα-Ser118 and pERα-Ser167 was inhibited, the induced apoptosis could be antagonized by the addition of estrogen, indicating that a mitochondrial pathway is involved. Therefore, pAKT and pERα or ERα could act cooperatively on coiled arterioles and endometrial cells in order to control menstrual cycle.