Zika Virus Causes Testis Damage and Leads to Male Infertility in Mice.

Zika virus (ZIKV) persists in the semen of male patients, a first for flavivirus infection. Here, we demonstrate that ZIKV can induce inflammation in the testis and epididymidis, but not in the prostate or seminal vesicle, and can lead to damaged testes after 60 days post-infection in mice. ZIKV induces innate immune responses in Leydig, Sertoli, and epididymal epithelial cells, resulting in the production of pro-inflammatory cytokines/chemokines. However, ZIKV does not induce a rapid and abundant cytokine production in peritubular cell and spermatogonia, suggesting that these cells are vulnerable for ZIKV infection and could be the potential repositories for ZIKV. Our study demonstrates a correlation between ZIKV and testis infection/damage and suggests that ZIKV infection, under certain circumstances, can eventually lead to male infertility.

A novel polypeptide encoded by the circular RNA ZKSCAN1 suppresses HCC via degradation of mTOR.

BACKGROUND: hsa_circ_0001727 (circZKSCAN1) has been reported to be a tumor-associated circRNA by sponging microRNAs. Intriguingly, we found that circZKSCAN1 encoded a secretory peptide (circZKSaa) in the liver. The present study aims to elucidate the potential role and molecular mechanism of circZKSaa in the regulation of hepatocellular carcinoma (HCC) progression. METHODS: The circRNA profiling datasets (RNA-seq data GSE143233 and GSE140202) were reanalyzed and circZKSCAN1 was selected for further study. Mass spectrometry, polysome fractionation assay, dual-luciferase reporter, and a series of experiments showed that circZKSCAN1 encodes circZKSaa. Cell proliferation, apoptosis, and tumorigenesis in nude mice were examined to investigate the functions of circZKSaa. Mechanistically, the relationship between the circZKSaa and mTOR in HCC was verified by immunoprecipitation analyses, mass spectrometry, and immunofluorescence staining analyses. RESULTS: Receiver operating characteristic (ROC) analysis demonstrated that the secretory peptide circZKSaa encoded by circZKSCAN1 might be the potential biomarker for HCC tissues. Through a series of experiments, we found that circZKSaa inhibited HCC progression and sensitize HCC cells to sorafenib. Mechanistically, we found that the sponge function of circZKSCAN1 to microRNA is weak in HCC, while overexpression of circZKSaa promoted the interaction of FBXW7 with the mammalian target of rapamycin (mTOR) to promote the ubiquitination of mTOR, thereby inhibiting the PI3K/AKT/mTOR pathway. Furthermore, we found that the high expression of cicZKSCAN1 in sorafenib-treated HCC cells was regulated by QKI-5. CONCLUSIONS: These results reveal that a novel circZKSCAN1-encoded peptide acts as a tumor suppressor on PI3K/AKT/mTOR pathway, and sensitizes HCC cells to sorafenib via ubiquitination of mTOR. These findings demonstrated that circZKSaa has the potential to serve as a therapeutic target and biomarker for HCC treatment.

circMRPS35 promotes malignant progression and cisplatin resistance in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death worldwide. Circular RNAs (circRNAs), a novel class of non-coding RNA, have been reported to be involved in the etiology of various malignancies. However, the underlying cellular mechanisms of circRNAs implicated in the pathogenesis of HCC remain unknown. In this study, we identified a functional RNA, hsa_circ_0000384 (circMRPS35), from public tumor databases using a set of computational analyses, and we further identified that circMRPS35 was highly expressed in 35 pairs of HCC from patients. Moreover, knockdown of the expression of circMRPS35 in Huh-7 and HCC-LM3 cells suppressed their proliferation, migration, invasion, clone formation, and cell cycle in vitro, and it suppressed tumor growth in vivo as well. Mechanically, circMRPS35 sponged microRNA-148a-3p (miR-148a), regulating the expression of Syntaxin 3 (STX3), which modulated the ubiquitination and degradation of phosphatase and tensin homolog (PTEN). Unexpectedly, we detected a peptide encoded by circMRPS35 (circMRPS35-168aa), which was significantly induced by chemotherapeutic drugs and promoted cisplatin resistance in HCC. These results demonstrated that circMRPS35 might be a novel mediator in HCC progress, and they raise the potential of a new biomarker for HCC diagnosis and prognosis, as well as a novel therapeutic target for HCC patients.

Serum amyloid A exhibits pH dependent antibacterial action and contributes to host defense against Staphylococcus aureus cutaneous infection.

Serum amyloid A (SAA), one of the major highly conserved acute-phase proteins in most mammals, is predominantly produced by hepatocytes and also by a variety of cells in extrahepatic tissues. It is well-known that the expression of SAA is sharply increased in bacterial infections. However, the exact physiological function of SAA during bacterial infection remains unclear. Herein, we showed that SAA expression significantly increased in abscesses of Staphylococcus aureus cutaneous infected mice, which exert direct antibacterial effects by binding to the bacterial cell surface and disrupting the cell membrane in acidic conditions. Mechanically, SAA disrupts anionic liposomes by spontaneously forming small vesicles or micelles under acidic conditions. Especially, the N-terminal region of SAA is necessary for membrane disruption and bactericidal activity. Furthermore, we found that mice deficient in SAA1/2 were more susceptible to infection by S. aureus In addition, the expression of SAA in infected skin was regulated by interleukin-6. Taken together, these findings support a key role of the SAA in host defense and may provide a novel therapeutic strategy for cutaneous bacterial infection.

Macrophage deletion of Noc4l triggers endosomal TLR4/TRIF signal and leads to insulin resistance.

In obesity, macrophages drive a low-grade systemic inflammation (LSI) and insulin resistance (IR). The ribosome biosynthesis protein NOC4 (NOC4) mediates 40 S ribosomal subunits synthesis in yeast. Hereby, we reported an unexpected location and function of NOC4L, which was preferentially expressed in human and mouse macrophages. NOC4L was decreased in both obese human and mice. The macrophage-specific deletion of Noc4l in mice displayed IR and LSI. Conversely, Noc4l overexpression by lentivirus treatment and transgenic mouse model improved glucose metabolism in mice. Importantly, we found that Noc4l can interact with TLR4 to inhibit its endocytosis and block the TRIF pathway, thereafter ameliorated LSI and IR in mice.

A new threat to human reproduction system posed by Zika virus (ZIKV): From clinical investigations to experimental studies.

Zika virus (ZIKV) was first isolated in 1947 from a rhesus monkey in the Zika forest of Uganda. ZIKV has since been silently circulating in a number of equatorial countries for over 50 years. The largest outbreak in humans occurred in Brazil in 2015-2016. Unlike its flavivirus relatives, sexual and post-transfusion transmissions of ZIKV have been reported. In addition, fetal infection can result in microcephaly and congenital Zikv syndrome has been reported in neonates. Moreover, ZIKV RNA can persist for at least 6 months in semen and 11 weeks in vaginal secretions after the infection, suggesting potential tropism for the male and female genital tracts. Accordingly, it is important to determine whether genital ZIKV infection could have deleterious effects on the male and female reproductive systems.

MicroRNA-27a-3p affects estradiol and androgen imbalance by targeting Creb1 in the granulosa cells in mouse polycytic ovary syndrome model.

Polycystic ovary syndrome (PCOS) is a common endocrine abnormality in women characterized by a menstrual disturbance with chronic anovulation and hyperandrogenism, polycystic ovaries, and insulin resistance. MicroRNAs (miRNAs) are important fine-tune regulators involved in various physiological and pathological processes, but their actions are not fully understood. In this study, we observed the increased expression of miR-27a-3p in the ovaries of mice with PCOS and explored its functions in primary mouse granulosa cells (mGCs) and the mouse granulosa-like tumor cell line, KK-1, using several approaches. QPCR results showed that miR-27a-3p expression was significantly higher in mGCs at the preantral follicle (PrF) stage. Using flow cytometry and hormone analysis, we found that overexpression of miR-27a-3p promoted apoptosis and inhibited estradiol (E2) production in KK-1 cells. Moreover using a luciferase assay and Western blotting analysis, we verified that the gene of cyclic AMP response element (CRE)-binding protein 1 (Creb1) was a potential target of miR-27a-3p, which in effect hindered the expression of its downstream factor cytochrome P450 family 19 subfamily A polypeptide 1 (Cyp19a1). With the decrease of aromatase activity, testosterone (T) is reduced to dihydrotestosterone (DHT) and this exerts its effect of upregulation of the miR-27a-3p expression. The imbalance of androgen and E2 levels affected by miR-27a-3p and its function of promoting GC apoptosis could be involved in the pathophysiology of PCOS. Our results indicate that miR-27a-3p in PCOS GCs may play an important role in ovarian follicular development and provide new insights into GC dysfunction in PCOS.