Microarray gene expression profiling and bioinformatics analysis of premature ovarian failure in a rat model

Dehydroepiandrosterone modulates the PTEN/PI3K/AKT signaling pathway to alleviate 4-vinylcyclohexene diepoxide-induced premature ovarian insufficiency in rats

Dehydroepiandrosterone (DHEA) is frequently integrated as an adjuvant in over a quarter of controlled ovarian hyperstimulation (COH) protocols, despite the ongoing debate regarding its impact. This study aimed to evaluate the efficacy and mechanism of action of DHEA on ovarian follicular development and ovarian response in rats with varying ovarian reserves. The study involved 75 rats categorized into 15 distinct groups. The ovarian tissues of rats in both the normal ovarian reserve group and the premature ovarian insufficiency (POI) group, induced by 4-vinylcyclohexene diepoxide (VCD) injection, were subjected to histomorphological and biochemical analyses following the administration of DHEA, either alone or in combination with COH. Follicle counting was performed on histological sections obtained from various tissues. Serum concentrations of anti-Müllerian hormone (AMH) and the quantification of specific proteins in ovarian tissue, including phosphatase and tensin homolog of chromosome 10 (PTEN), phosphoinositide 3-kinase (PI3K), phosphorylated protein kinase B (pAKT), cyclooxygenase 2 (COX-2), caspase-3, as well as assessments of total antioxidant status and total oxidant status, were conducted employing the ELISA method. The impact of DHEA exhibited variability based on ovarian reserve. In the POI model, DHEA augmented follicular development and ovarian response to the COH protocol by upregulating the PTEN/PI3K/AKT signaling pathway, mitigating apoptosis, inflammation, and oxidative stress, contrary to its effects in the normal ovarian reserve group. In conclusion, it has been determined that DHEA may exert beneficial effects on ovarian stimulation response by enhancing the initiation of primordial follicles and supporting antral follicle populations.

Current understanding of the genomic abnormities in premature ovarian failure: chance for early diagnosis and management

Premature ovarian failure (POF) is an insidious cause of female infertility and a devastating condition for women. POF also has a strong familial and heterogeneous genetic background. Management of POF is complicated by the variable etiology and presentation, which are generally characterized by abnormal hormone levels, gene instability and ovarian dysgenesis. To date, abnormal regulation associated with POF has been found in a small number of genes, including autosomal and sex chromosomal genes in folliculogenesis, granulosa cells, and oocytes. Due to the complex genomic contributions, ascertaining the exact causative mechanisms has been challenging in POF, and many pathogenic genomic characteristics have yet to be elucidated. However, emerging research has provided new insights into genomic variation in POF as well as novel etiological factors, pathogenic mechanisms and therapeutic intervention approaches. Meanwhile, scattered studies of transcriptional regulation revealed that ovarian cell function also depends on specific biomarker gene expression, which can influence protein activities, thus causing POF. In this review, we summarized the latest research and issues related to the genomic basis for POF and focused on insights gained from their biological effects and pathogenic mechanisms in POF. The present integrated studies of genomic variants, gene expression and related protein abnormalities were structured to establish the role of etiological genes associated with POF. In addition, we describe the design of some ongoing clinical trials that may suggest safe, feasible and effective approaches to improve the diagnosis and therapy of POF, such as Filgrastim, goserelin, resveratrol, natural plant antitoxin, Kuntai capsule et al. Understanding the candidate genomic characteristics in POF is beneficial for the early diagnosis of POF and provides appropriate methods for prevention and drug treatment. Additional efforts to clarify the POF genetic background are necessary and are beneficial for researchers and clinicians regarding genetic counseling and clinical practice. Taken together, recent genomic explorations have shown great potential to elucidate POF management in women and are stepping from the bench to the bedside.

PKC-βII is downregulated in the premature ovarian failure SD rat model

We investigated the role of protein kinase c (PKC) -α and -β during the ovarian follicular dynamics using estrous cycle, gonadotropin-induced ovulation, and antral follicle culture, 4-vinylcyclohexene diepoxide (VCD)-induced premature ovarian failure (POF) in the SD rat models. We found the higher activity of PKC during the proestrus stage along with expression of PKC-α during the estrus and metestrus stages of the estrous cycle while PKC-β expression was increased during the diestrus, proestrus, and estrus stages. In response to pregnant mare gonadotropin (PMSG)-induced follicular recruitment and ovulation, the phosphorylated (Thr-642) PKC-β was increased. PKC activity inhibition by hispidin during the proestrus stage resulted in decreased antral follicles and corpus luteum. Treatment with hispidin resulted in the downregulation of granulosa cell (GC) biomarker, follicle stimulating hormone receptor (FSHR) expression in the cultured pre-antral follicle. During the forskolin-induced luteinization of human granulosa cells, the expression level of PKC-α and β (I and II) was decreased. In the POF condition, the activity of total PKC and the expression levels of PKC-α and β (I and II) were increased. Immunostaining depicted ubiquitous expression of PKC-α in the ovary during the estrous cycle and POF conditions. Taken together, we conclude the association of PKC-α and -β (I and II) during ovarian follicular dynamics where the expression level of PKC-α is increased, but the expression level of PKC-β (I and II) is suppressed in the POF condition in the SD rat model.

MiRNA-190a-5p promotes primordial follicle hyperactivation by targeting PHLPP1 in premature ovarian failure

We previously screened 6 differentially expressed miRNAs in ovarian tissues of 4-vinylcyclohexene diepoxide (VCD)-treated premature ovarian failure (POF) model in SD rats, including miRNA-190a-5p, miRNA-98-5p, miRNA-29a-3p, miRNA-144-5p, miRNA-27b-3p, miRNA-151-5p. In this study, to investigate the mechanisms causing the onset of POF, we first identified miRNAs with earlier differential expression at consecutive time points in the VCD-treated rat POF model and explored the mechanisms by which the target miRNAs promote POF. The SD rats were injected with VCD for 15 days to induce POF. Additionally, we collected rat blood and ovaries at the same time every day for 15 consecutive days, and luteinizing hormone (LH), follicle-stimulating hormone (FSH), Anti-Mullerian hormone (AMH), and estradiol (E2) serum levels were detected by ELISA. Six miRNAs expression were measured in rat ovaries by qRT-PCR. Dual-luciferase reporter gene assays were employed to predict and verify the target gene (PHLPP1) of target miRNAs (miRNA-190a-5p). Western blot was examined to detect the expression levels of PHLPP1, AKT, p-AKT, FOXO3a, p-FOXO3a, and LHR proteins on the target gene PHLPP1 and its participation in the primordial follicular hyperactivation-related pathways (AKT-FOXO3a and AKT-LH/LHR). During the VCD modeling POF rat ovaries, miRNA-190a-5p was the first to show significant differential expression, i.e., 6th of VCD treating, and PHLPP1 was verified to be a direct downstream target of it. Starting from the 6th of VCD treatment, the more significant the up-regulation trend of miRNA-190a-5p expression, the more obvious the down-regulation trend of PHLPP1 and LHR mRNA and protein expression, accompanied by the more severe phosphorylation of AKT and FOXO3a proteins, thus continuously over-activating the rat primordial follicle to promote the development of POF. In conclusion, miRNA-190a-5p may become a potential biomarker for early screening of POF, and it can continuously activate primordial follicles in rats by targeting the expression of PHLPP1 and key proteins in the AKT-FOXO3a and AKT-LH/LHR pathways.

Protective effect of alpha lipoic acid on 4-vinylcyclohexene diepoxide induced primary ovarian failure in female rats

OBJECTIVE

The effects of alpha lipoic acid (ALA) and its possible mechanisms in treating Primary ovarian failure (POF) model was studied with 4 vinylcyclohexene diepoxide (VCD).

MATERIAL AND METHODS

Rats were divided into 4 groups (n = 7) as Control, VCD, VCD + ALA and ALA. POF model was induced by applying VCD intraperitoneally and ALA was administered by oral gavage as 100 mg/day to the VCD + ALA and ALA groups.

RESULTS

At the end of 42 days, ovarian and uterine tissues were received. The number of primordial and primary follicles were increased and corpus luteum and cystic follicles were decreased in ovarian tissues in VCD + ALA group compared to VCD group. Caspase-3 immunoreactivity in follicular cells was decreased in VCD + ALA group compared to VCD group. eNOS immunoreactivity and eNOS levels were decreased in VCD group and increased in VCD + ALA group while iNOS immunoreactivity and iNOS levels were increased in VCD group, decreased in VCD + ALA group in ovary and uterine tissue. Plasma FSH and LH hormone levels were increased in the VCD but decreased in VCD + ALA group. Estradiol level decreased in the VCD group compared to the other groups. The MDA values were significantly increased in the VCD + ALA group compared to VCD group. In addition, the levels of GSH values were decreased in VCD + ALA group compared to VCD group.

CONCLUSION

Alpha lipoic acid treatment of rats with VCD-induced POF had a beneficial effect on reducing ovarian damage by improving histological, immunohistochemical, hormone level and oxidative stress markers. Our results show that ALA is an effective treatment of VCD-induced POF rats.

The role of miRNAs in regulating adrenal and gonadal steroidogenesis

miRNAs are endogenous noncoding single-stranded small RNAs of ~22 nucleotides in length that post-transcriptionally repress the expression of their various target genes. They contribute to the regulation of a variety of physiologic processes including embryonic development, differentiation and proliferation, apoptosis, metabolism, hemostasis and inflammation. In addition, aberrant miRNA expression is implicated in the pathogenesis of numerous diseases including cancer, hepatitis, cardiovascular diseases and metabolic diseases. Steroid hormones regulate virtually every aspect of metabolism, and acute and chronic steroid hormone biosynthesis is primarily regulated by tissue-specific trophic hormones involving transcriptional and translational events. In addition, it is becoming increasingly clear that steroidogenic pathways are also subject to post-transcriptional and post-translational regulations including processes such as phosphorylation/dephosphorylation, protein‒protein interactions and regulation by specific miRNAs, although the latter is in its infancy state. Here, we summarize the recent advances in miRNA-mediated regulation of steroidogenesis with emphasis on adrenal and gonadal steroidogenesis.

Molecular pathogenesis involved in human idiopathic pulmonary fibrosis based on an integrated microRNA‑mRNA interaction network

Idiopathic pulmonary fibrosis (IPF) is considered to be an ailment of the lungs that cannot be cured, wherein the lung tissues are characterized by increased thickness and stiffness, and/or scars. Despite the fact that extensive success has been achieved regarding the molecular diagnostics and pathobiology, the basic pathogenesis associated with IPF has not yet been fully elucidated and requires further clarification. In the current research, the changes in microRNA (miRNA) and mRNA expression in IPF were investigated through an integrative network technique. The authentic miRNA and mRNA expression profiling datasets were downloaded from Gene Expression Omnibus, followed by identification of differentially expressed miRNAs and mRNAs with use of the Significance Analysis of Microarrays algorithm. Expansion of the molecular targets associated with miRNAs was performed with the use of CyTargetLinker in Cytoscape, which was succeeded by validation with the use of mRNA array expression profiling. The incorporated miRNA‑mRNA network covered 27 genes, in addition to 22 miRNAs that were associated with IPF development. As revealed by the functional enrichment analysis, the cytokine‑cytokine receptor interaction and glycine, serine and threonine metabolism signalling pathways were extensively associated with IPF development. Overall, the present incorporated network illustrated the key link between miRNA and genes in IPF; in particular, it was elucidated that miR‑409‑5p and has‑miR‑376c, together with their target genes (C‑C motif chemokine ligand 20 and oncostatin M), are likely candidates involved in the promotion of IPF initiation and progression.

Exploring the molecular mechanism associated with breast cancer bone metastasis using bioinformatic analysis and microarray genetic interaction network

BACKGROUND

Bone metastases are common in advanced breast cancer patients and frequently leading to skeletal-related morbidity and deterioration in the quality of life. Although chemotherapy and hormone therapy are able to control the symptoms caused by bone destruction, the underlying molecular mechanisms for the affinity of breast cancer cells towards skeletal bones are still not completely understood.

METHODS

In this study, bioinformatic analysis was performed on patients' microarray gene expression data to explore the molecular mechanism associated with breast cancer bone metastasis. Microarray gene expression profile regarding patients with breast cancer and disseminated tumor cells was downloaded from Gene Expression Omnibus (GEO) database (NCBI, NIH). Raw data were normalized and differently expressed genes were identified by using Significance Analysis of Microarrays (SAM) methods. Protein interaction networks were expanded using String. Moreover, molecular functions, biological processes and signaling pathway enrichment analysis were performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG).

RESULTS

We identified 66 differentially expressed genes. After submitting the set of genes to String, genetic interaction network was expanded, which consisted of 110 nodes and 869 edges. Pathway enrichment analysis suggested that adhesion kinase, ECM-receptor interaction, calcium signaling, Wnt pathways, and PI3K/AKT signaling pathway are highly associated with breast cancer bone metastasis.

CONCLUSION

In this study, we established a microarray genetic interaction network associated with breast cancer bone metastasis. This information provides some potential molecular therapeutic targets for breast cancer initiation and progression.

Effects of chronic unpredictable mild stress on ovarian reserve in female rats: Feasibility analysis of a rat model of premature ovarian failure

Premature ovarian failure (POF) results from a number of disorders. The POF model is primarily based on chemotherapeutic injury, and hence is not suitable for assessing the effects of chronic stress on ovarian function. Therefore, improved animal models are required to analyze the effects of chronic stress on ovarian reserve. The feasibility of the chronic unpredictable mild stress (CUMS) method for establishing a model of POF was examined. The depressive behavior exhibited by rats was evaluated with the open field and sucrose preference tests. Vaginal smears were obtained for assessment of the estrous cycle. The ovarian reserve of the animals was evaluated using the estrous cycle, ovarian histology and serum levels of gonadotropin releasing hormone (GnRH), follicle‑stimulating hormone (FSH), estradiol (E2), and anti‑Müllerian hormone (AMH). Compared with the control group, body weight, time spent in the center, horizontal movement, vertical frequency, consumption of sucrose, sucrose preference, number of small follicles from the rats, and serum E2, AMH and GnRH levels were significantly decreased in the CUMS group (all P<0.05). However, the estrous cycle was prolonged significantly (P<0.05) and serum FSH levels were increased significantly (P<0.01). These results suggested that the CUMS model rats exhibited depression‑like behaviors. CUMS may induce psychological stress and decrease ovarian reserve in female rats. Thus, the CUMS model may be used to assess the effects of chronic stress on female reproductive function.

A genome-wide association scan of biological processes involved in oral lichen planus and oral squamous cell carcinoma

BACKGROUND

In this study, the molecular mechanisms underlying malignant transformation from oral lichen planus (OLP) to oral squamous cell carcinoma (OSCC) were examined.

METHODS

High-throughput sequencing of long noncoding RNAs (lncRNAs) and mRNAs of normal subjects and patients with OLP and OSCC was conducted. RNA-seq reads were mapped, lncRNA and mRNA transcripts were assembled, and expression levels were estimated. The targets of lncRNAs were predicted. Finally, Gene Ontology (GO) and pathway enrichment analyses of differentially expressed genes (DEGs) and lncRNA targets were performed.

RESULTS

High-quality sequence data were generated and the mapping ratios for OSCC, normal, and OLP samples were high. In total, 820, 656, and 582 DEGs were obtained from OPL vs. normal, OSCC vs. normal, and OSCC vs. OPL, respectively. A total of 1721 known lncRNAs and 133 predicted lncRNAs and targets were obtained. Keratinization was significantly enriched by OSCC-related DEGs, but not OPL-related DEGs. The pathway of olfactory transduction was enriched by OPL- and OSCC-related DEGs. Defense response to virus and viral carcinogenesis were enriched by DEGs and lncRNA targets in all comparisons. GO term related to the metabolic process was enriched by lncRNA targets in the OPL vs normal comparison, and antigen processing and presentation via MHC class I was significantly enriched by lncRNA targets in the other 2 comparisons.

CONCLUSION

Keratinization and MHC class I antigen processing and presentation were activated during the malignant transformation from OLP to OSCC. Additionally, the olfactory transduction pathway may be important for OSCC.

Clarifying the molecular mechanism associated with carfilzomib resistance in human multiple myeloma using microarray gene expression profile and genetic interaction network

Carfilzomib is a Food and Drug Administration-approved selective proteasome inhibitor for patients with multiple myeloma (MM). However, recent studies indicate that MM cells still develop resistance to carfilzomib, and the molecular mechanisms associated with carfilzomib resistance have not been studied in detail. In this study, to better understand its potential resistant effect and its underlying mechanisms in MM, microarray gene expression profile associated with carfilzomib-resistant KMS-11 and its parental cell line was downloaded from Gene Expression Omnibus database. Raw fluorescent signals were normalized and differently expressed genes were identified using Significance Analysis of Microarrays method. Genetic interaction network was expanded using String, a biomolecular interaction network JAVA platform. Meanwhile, molecular function, biological process and signaling pathway enrichment analysis were performed based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Totally, 27 upregulated and 36 downregulated genes were identified and a genetic interaction network associated with the resistant effect was expanded basing on String, which consisted of 100 nodes and 249 edges. In addition, signaling pathway enrichment analysis indicated that cytokine–cytokine receptor interaction, autophagy, ErbB signaling pathway, microRNAs in cancer and fatty acid metabolism pathways were aberrant in carfilzomib-resistant KMS-11 cells. Thus, in this study, we demonstrated that carfilzomib potentially conferred drug resistance to KMS-11 cells by cytokine–cytokine receptor interaction, autophagy, ErbB signaling pathway, microRNAs in cancer and fatty acid metabolism pathways, which may provide some potential molecular therapeutic targets for drug combination therapy against carfilzomib resistance.