Autophagy, a critical element in the aging male reproductive disorders and prostate cancer: a therapeutic point of view.

Autophagy is a highly conserved, lysosome-dependent biological mechanism involved in the degradation and recycling of cellular components. There is growing evidence that autophagy is related to male reproductive biology, particularly spermatogenic and endocrinologic processes closely associated with male sexual and reproductive health. In recent decades, problems such as decreasing sperm count, erectile dysfunction, and infertility have worsened. In addition, reproductive health is closely related to overall health and comorbidity in aging men. In this review, we will outline the role of autophagy as a new player in aging male reproductive dysfunction and prostate cancer. We first provide an overview of the mechanisms of autophagy and its role in regulating male reproductive cells. We then focus on the link between autophagy and aging-related diseases. This is followed by a discussion of therapeutic strategies targeting autophagy before we end with limitations of current studies and suggestions for future developments in the field.

Normoxic HIF-1α Stabilization Caused by Local Inflammatory Factors and Its Consequences in Human Coronary Artery Endothelial Cells.

Knowledge about normoxic hypoxia-inducible factor (HIF)-1α stabilization is limited. We investigated normoxic HIF-1α stabilization and its consequences using live cell imaging, immunoblotting, Bio-Plex multiplex immunoassay, immunofluorescence staining, and barrier integrity assays. We demonstrate for the first time that IL-8 and M-CSF caused HIF-1α stabilization and translocation into the nucleus under normoxic conditions in both human coronary endothelial cells (HCAECs) and HIF-1α-mKate2-expressing HEK-293 cells. In line with the current literature, our data show significant normoxic HIF-1α stabilization caused by TNF-α, INF-γ, IL-1ß, and IGF-I in both cell lines, as well. Treatment with a cocktail consisting of TNF-α, INF-γ, and IL-1ß caused significantly stronger HIF-1α stabilization in comparison to single treatments. Interestingly, this cumulative effect was not observed during simultaneous treatment with IL-8, M-CSF, and IGF-I. Furthermore, we identified two different kinetics of HIF-1α stabilization under normoxic conditions. Our data demonstrate elevated protein levels of HIF-1α-related genes known to be involved in the development of atherosclerosis. Moreover, we demonstrate an endothelial barrier dysfunction in HCAECs upon our treatments and during normoxic HIF-1α stabilization comparable to that under hypoxia. This study expands the knowledge of normoxic HIF-1α stabilization and activation and its consequences on the endothelial secretome and barrier function. Our data imply an active role of HIF-1α in vivo in the vasculature in the absence of hypoxia.

A Barrier to Defend - Models of Pulmonary Barrier to Study Acute Inflammatory Diseases.

Pulmonary diseases represent four out of ten most common causes for worldwide mortality. Thus, pulmonary infections with subsequent inflammatory responses represent a major public health concern. The pulmonary barrier is a vulnerable entry site for several stress factors, including pathogens such as viruses, and bacteria, but also environmental factors e.g. toxins, air pollutants, as well as allergens. These pathogens or pathogen-associated molecular pattern and inflammatory agents e.g. damage-associated molecular pattern cause significant disturbances in the pulmonary barrier. The physiological and biological functions, as well as the architecture and homeostatic maintenance of the pulmonary barrier are highly complex. The airway epithelium, denoting the first pulmonary barrier, encompasses cells releasing a plethora of chemokines and cytokines, and is further covered with a mucus layer containing antimicrobial peptides, which are responsible for the pathogen clearance. Submucosal antigen-presenting cells and neutrophilic granulocytes are also involved in the defense mechanisms and counterregulation of pulmonary infections, and thus may directly affect the pulmonary barrier function. The detailed understanding of the pulmonary barrier including its architecture and functions is crucial for the diagnosis, prognosis, and therapeutic treatment strategies of pulmonary diseases. Thus, considering multiple side effects and limited efficacy of current therapeutic treatment strategies in patients with inflammatory diseases make experimental in vitro and in vivo models necessary to improving clinical therapy options. This review describes existing models for studyying the pulmonary barrier function under acute inflammatory conditions, which are meant to improve the translational approaches for outcome predictions, patient monitoring, and treatment decision-making.

Cigarette Smoke Extract Disturbs Mitochondria-Regulated Airway Epithelial Cell Responses to Pneumococci.

Mitochondrial functionality is crucial for the execution of physiologic functions of metabolically active cells in the respiratory tract including airway epithelial cells (AECs). Cigarette smoke is known to impair mitochondrial function in AECs. However, the potential contribution of mitochondrial dysfunction in AECs to airway infection and airway epithelial barrier dysfunction is unknown. In this study, we used an in vitro model based on AECs exposed to cigarette smoke extract (CSE) followed by an infection with Streptococcus pneumoniae (Sp). The levels of oxidative stress as an indicator of mitochondrial stress were quantified upon CSE and Sp treatment. In addition, expression of proteins associated with mitophagy, mitochondrial content, and biogenesis as well as mitochondrial fission and fusion was quantified. Transcriptional AEC profiling was performed to identify the potential changes in innate immune pathways and correlate them with indices of mitochondrial function. We observed that CSE exposure substantially altered mitochondrial function in AECs by suppressing mitochondrial complex protein levels, reducing mitochondrial membrane potential and increasing mitochondrial stress and mitophagy. Moreover, CSE-induced mitochondrial dysfunction correlated with reduced enrichment of genes involved in apical junctions and innate immune responses to Sp, particularly type I interferon responses. Together, our results demonstrated that CSE-induced mitochondrial dysfunction may contribute to impaired innate immune responses to Sp.

Role of air pollutants in airway epithelial barrier dysfunction in asthma and COPD.

Chronic exposure to environmental pollutants is a major contributor to the development and progression of obstructive airway diseases, including asthma and COPD. Understanding the mechanisms underlying the development of obstructive lung diseases upon exposure to inhaled pollutants will lead to novel insights into the pathogenesis, prevention and treatment of these diseases. The respiratory epithelial lining forms a robust physicochemical barrier protecting the body from inhaled toxic particles and pathogens. Inhalation of airborne particles and gases may impair airway epithelial barrier function and subsequently lead to exaggerated inflammatory responses and airway remodelling, which are key features of asthma and COPD. In addition, air pollutant-induced airway epithelial barrier dysfunction may increase susceptibility to respiratory infections, thereby increasing the risk of exacerbations and thus triggering further inflammation. In this review, we discuss the molecular and immunological mechanisms involved in physical barrier disruption induced by major airborne pollutants and outline their implications in the pathogenesis of asthma and COPD. We further discuss the link between these pollutants and changes in the lung microbiome as a potential factor for aggravating airway diseases. Understanding these mechanisms may lead to identification of novel targets for therapeutic intervention to restore airway epithelial integrity in asthma and COPD.

Airway tight junctions as targets of viral infections.

The apical junctional complexes (AJCs) of airway epithelial cells are a key component of the innate immune system by creating barriers to pathogens, inhaled allergens, and environmental particles. AJCs form between adjacent cells and consist of tight junctions (TJs) and adherens junctions (AJs). Respiratory viruses have been shown to target various components of the AJCs, leading to airway epithelial barrier dysfunction by different mechanisms. Virus-induced epithelial permeability may allow for allergens and bacterial pathogens to subsequently invade. In this review, we discuss the pathophysiologic mechanisms leading to disruption of AJCs and the potential ensuing ramifications. We focus on the following viruses that affect the pulmonary system: respiratory syncytial virus, rhinovirus, influenza viruses, immunodeficiency virus, and other viruses such as coxsackievirus, adenovirus, coronaviruses, measles, parainfluenza virus, bocavirus, and vaccinia virus. Understanding the mechanisms by which viruses target the AJC and impair barrier function may help design therapeutic innovations to treat these infections.

Helicobacter pylori Recombinant CagA Regulates Th1/Th2 Balance in a BALB/c Murine Model.

Purpose: Helicobacter pylori is recognized as one of the prevalent causes of human gastricinfection. In the present study, the role of mixed immunization with H. pylori lipopolysaccharide(LPS) and recombinant cytotoxin-associated gene A (rCagA) as a stimulator of host immuneresponses was determined. Methods: BALB/c mice were immunized with different formulations by the systemic administrationat 14-day intervals. The effects of the formulations plus CpG adjuvants were assessed before andpost-immunization in separated studies. Moreover, the expression of Th1/Th2 cytokines wasquantified in sera of immunized mice using reverse transcription polymerase chain reaction (RTPCR)test and the protein levels confirmed with enzyme linked immunosorbent assay (ELISA).Finally, the specific antibody levels in sera were studied by ELISA and the tendency of cellularresponse was examined by IgG1/IgG2a ratio. Results: Data of Western blotting verified the presence of constructed protein. Analysisof lymphocyte proliferation showed that CpG-conjugated rCagA increases lymphocytesproliferation compared to the control group. Also, it was shown that formulations containing LPSand rCagA promote a Th1 response indicated by interferon-gamma expression and induced Th1/Th2 balance. Additionally, the specific IgG1, total IgG and IgG2a levels elevated in response toall treatments. Ultimately, the IgG2a/IgG1 ratio in the mice immunized with rCagA-containingformulations increased. Conclusion: These results indicated that rCagA protein carried with CpG adjuvant not onlymaintained its antigenicity throughout the experiment but also induced robust Th1-biasedimmune responses. Therefore, it holds promise for the production of an efficient vaccine against H. pylori infection.

Early Career Members at the ERS Lung Science Conference 2020: metabolic alterations in lung ageing and disease.

The Lung Science Conference 2020 brought together leading experts in the field to discuss the latest cutting-edge science, as well as various career development opportunities for early career members https://bit.ly/2XZ5YGQ.

Mitochondria: at the crossroads of regulating lung epithelial cell function in chronic obstructive pulmonary disease.

Disturbances in mitochondrial structure and function in lung epithelial cells have been implicated in the pathogenesis of various lung diseases, including chronic obstructive pulmonary disease (COPD). Such disturbances affect not only cellular energy metabolism but also alter a range of indispensable cellular homeostatic functions in which mitochondria are known to be involved. These range from cellular differentiation, cell death pathways, and cellular remodeling to physical barrier function and innate immunity, all of which are known to be impacted by exposure to cigarette smoke and have been linked to COPD pathogenesis. Next to their well-established role as the first physical frontline against external insults, lung epithelial cells are immunologically active. Malfunctioning epithelial cells with defective mitochondria are unable to maintain homeostasis and respond adequately to further stress or injury, which may ultimately shape the phenotype of lung diseases. In this review, we provide a comprehensive overview of the impact of cigarette smoke on the development of mitochondrial dysfunction in the lung epithelium and highlight the consequences for cell function, innate immune responses, epithelial remodeling, and epithelial barrier function in COPD. We also discuss the applicability and potential therapeutic value of recently proposed strategies for the restoration of mitochondrial function in the treatment of COPD.

Treating cancer with microRNA replacement therapy: A literature review.

microRNAs (miRNAs) are small non-coding RNAs that regulate gene expression post-transcriptionally by interfering with the translation of one or more target mRNAs. The unique miRNA sequences are involved in many physiological and pathological processes. Dysregulation of miRNAs contributes to the pathogenesis of all types of cancer. Notably, the diminished expression of tumor suppressor miRNAs, such as members of the Let-7 and miR-34 family, promotes tumor progression, invasion and metastasis. The past lustrum in particular, has witnessed substantial improvement of miRNA replacement therapy. This approach aims to restore tumor suppressor miRNA function in tumor cells using synthetic miRNA mimics or miRNA expression plasmids. Here, we provide a comprehensive review of recent advances in miRNA replacement therapy for treatment of cancer and its advantages over conventional gene therapy. We discuss a wide variety of delivery methods and vectors, as well as obstacles that remain to be overcome. Lastly, we review efforts to reverse epigenetic alterations, which affect miRNA expression in cancer cells, and the promising observation that restoring miRNA function re-sensitizes resistant tumor cells to chemotherapeutic drugs. The fact that various miRNA replacement therapies are currently in clinical trial demonstrates the great potential of this approach to treat cancer.

Airway Epithelial Barrier Dysfunction in Chronic Obstructive Pulmonary Disease: Role of Cigarette Smoke Exposure.

The epithelial lining of the airway forms the first barrier against environmental insults, such as inhaled cigarette smoke, which is the primary risk factor for the development of chronic obstructive pulmonary disease (COPD). The barrier is formed by airway epithelial junctions, which are interconnected structures that restrict permeability to inhaled pathogens and environmental stressors. Destruction of the epithelial barrier not only exposes subepithelial layers to hazardous agents in the inspired air, but also alters the normal function of epithelial cells, which may eventually contribute to the development of COPD. Of note, disruption of epithelial junctions may lead to modulation of signaling pathways involved in differentiation, repair, and proinflammatory responses. Epithelial barrier dysfunction may be particularly relevant in COPD, where repeated injury by cigarette smoke exposure, pathogens, inflammatory mediators, and impaired epithelial regeneration may compromise the barrier function. In the current review, we discuss recent advances in understanding the mechanisms of barrier dysfunction in COPD, as well as the molecular mechanisms that underlie the impaired repair response of the injured epithelium in COPD and its inability to redifferentiate into a functionally intact epithelium.

Urtica dioica Extract Inhibits Proliferation and Induces Apoptosis and Related Gene Expression of Breast Cancer Cells In Vitro and In Vivo.

INTRODUCTION: Currently, because the prevalence of breast cancer and its consequent mortality has increased enormously in the female population, a number of studies have been designed to identify natural products with special antitumor properties. The main purpose of the present study was to determine the effect of Urtica dioica on triggering apoptosis and diminishing growth, size, and weight of the tumor in an allograft model of BALB/c mice. MATERIALS AND METHODS: In the present study, a BALB/c mouse model of breast cancer (4T1) was used. After emergence of tumor, 2 groups of mice received the extract, 1 group at a dose of 10 mg/kg and 1 group at a dose of 20 mg/kg, by intraperitoneal injection for 28 days. During the test and after removal of the tumor mass, the size and weight of the tumor were measured. To assess the induction of apoptosis in the cancer cells, the TUNEL (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling) assay was performed. The Ki-67 test was used to evaluate tumor proliferation. RESULTS: The results showed that the tumor size in the mice treated with the extract decreased significantly. The weight of the tumor mass in the treated mice after resection was less than that in the control group. The TUNEL assay findings revealed that apoptosis occurred in the treated group. The Ki-67 test findings also demonstrated that administration of the extract suppressed the growth of tumor cells. CONCLUSION: These results suggest that U. dioica extract can decrease the growth of breast tumors and induce apoptosis in tumor cells; thus, it might represent an ideal therapeutic tool for breast cancer.

Function of microRNA-143 in different signal pathways in cancer: New insights into cancer therapy.

MicroRNAs (miRNAs) are small non-coding RNAs which participate in the post-transcriptional regulation of gene expression. They play important roles in cellular events such as growth and differentiation. Deregulation of miRNAs is frequently evident in human cancers where their aberrant expression is associated with uncontrolled proliferation, metastasis, impaired cell cycle and DNA damage response. The miRNAs are important in cancer as ∼50% of miRNA genes are located in cancer-associated regions such as fragile sites of genome. MiRNA-143 is defined as an important tumor suppressor in a variety of neoplasms including solid tumors and B-cell malignancies. MiRNA-143 is involved in the pathogenesis of cancers by directly targeting several mRNAs such as Bcl-2, KRAS, HK2, DNMT3A, TP53 and MMP-13. In this study, an overview of the miRNA-143 function in different signaling pathways in cancer will be provided.

The Urtica dioica extract enhances sensitivity of paclitaxel drug to MDA-MB-468 breast cancer cells.

INTRODUCTION: Due to the chemo resistant nature of cancer cells and adverse effects of current therapies, researchers are looking for the most efficient therapeutic approach which has the lowest side effects and the highest toxicity on cancer cells. The aim of the present study was to investigate the synergic effect of Urtica dioica extract in combination with paclitaxel on cell death and invasion of human breast cancer MDA-MB-468 cell line. MATERIALS AND METHODS: To determine the cytotoxic effects of Urtica dioica extract with paclitaxel, MTT assay was performed. The scratch test was exploited to assess the effects of Urtica dioica, Paclitaxel alone and combination on migration of cancer cells. The expression levels of snail-1, ZEB1, ZEB2, twist, Cdc2, cyclin B1 and Wee1 genes were quantified using qRT-PCR and western blot performed for snail-1expression. The effects of plant extract, Paclitaxel alone and combination on different phases of cell cycle was analyzed using flow cytometry. RESULTS: Results of MTT assay showed that Urtica dioica significantly destroyed cancer cells. Interestingly, Concurrent use of Urtica dioica extract with paclitaxel resulted in decreased IC50 dose of paclitaxel. Moreover, findings of scratch assay exhibited the inhibitory effects of Urtica dioica, Paclitaxel alone and combination on migration of MDA-MB-468 cell line. Our findings also demonstrated that the extract substantially decreased the Snail-1 and related gene expression. Ultimately, Cell cycle arrest occurred at G2/M phase post-treatment by deregulating Cdc2 and wee1. CONCLUSIONS: Our results demonstrated that the dichloromethane extract of Urtica dioica inhibit cell growth and migration. Also, Urtica dioica extract substantially increased sensitivity of breast cancer cells to paclitaxel. Therefore, it can be used as a potential candidate for treatment of breast cancer with paclitaxel.

The immunomodulatory activity of secondary metabolites isolated from Streptomyces calvus on human peripheral blood mononuclear cells.

BACKGROUND: The natural products derived from micro-organisms are potential candidates for the discovery of novel drugs. Streptomyces bacteria are prolific sources of secondary metabolites with a wide variety of biological activities. Streptomyces calvus (S. calvus) is one strain of this genus and may be an appropriate candidate for isolating new compounds. In this study, the immunomodulatory effects of S. calvus secondary metabolites on the expression of various cytokine genes by human peripheral blood mononuclear cells (PBMCs) were evaluated. METHODS: A bacterial sample was inoculated in Mueller Hinton Broth and secondary metabolites were extracted. PBMCs were isolated from venous blood and were treated with S. calvus secondary metabolites for 48 h. The cell proliferation was assessed by Methyl tetrazolium bromide (MTT) assay and quantitative real-time polymerase chain reaction (qRT-PCR) assays to survey mRNA expressions of selected pro-inflammatory and inhibitory cytokine genes. RESULTS: Secondary metabolites augmented interleukin-2 and interferon-γ gene expression in PBMCs at low doses and also reduced the levels of immunosuppressive cytokine interleukin-10. In addition, the proliferation of PBMCs substantially increased in response to metabolite treatment in a concentration-dependent manner (p < 0.001). CONCLUSION: This in vitro study revealed that the secondary metabolites from S. calvus can successfully stimulate human PBMCs. Therefore, these metabolites have the potential to serve as robust immunomodulators.

The Herbal Medicine Utrica Dioica Inhibits Proliferation of Colorectal Cancer Cell Line by Inducing Apoptosis and Arrest at the G2/M Phase.

BACKGROUND: One of the major causes of cancer death internationally and the third most prevalent cancer in the world has been diagnosed with colorectal cancer. Although current routine treatments of cancer have been successful in some extent, mortality caused by adverse effects of these strategies is still raising. Medicinal plants are potential sources of anticancer compounds and can be exploited as a powerful complementary tool. This study aimed to investigate the cytotoxic effects of nettle extract on mouse colorectal cancer cells, HCT. MATERIALS AND METHODS: In the present study, to evaluate the cytotoxicity of nettle extract, MTT assay and trypan blue were performed. Subsequently, DNA fragmentation and TUNEL test was carried out for determination of apoptosis. Real-time PCR test was used to quantify the expression of Caspase-3, Caspase-9, and Bcl-2 which is involved in apoptosis regulation. Finally, cell cycle analysis was conducted by using flow cytometry. RESULTS: The results of MTT assay showed that the dichloromethane extract of U. dioica extract significantly destroyed cancer cells HCT-116. DNA fragmentation and TUNEL test demonstrated that Utrica extract elicited apoptotic response in the cancer cells. The messenger RNA (mRNA) expression levels of Caspase-3 and Caspase-9 markedly increased, while the Bcl-2 gene was conversely downregulated. Findings of flow cytometry confirmed that cell cycle arrest has occurred at the G2 phase. CONCLUSION: Taken together, our experiment showed that subjecting HCT-116 cells to dichloromethane extract of nettle (U. dioica), increases turnover of these cells. Thus, it may be a useful agent in the treatment of colorectal cancer.