Modulation of NRF2/KEAP1 Signaling by Phytotherapeutics in Periodontitis.

Periodontitis affects up to 40% of adults over 60 years old and is a consequence of gingivitis. Periodontitis is characterized by a chronic inflammation, periodontal damage, and alveolar bone resorption. The nuclear factor erythroid 2-related factor 2 (NFE2L2 or NRF2)/Kelch-like ECH-Associated Protein 1 (KEAP1) (NRF2/KEAP1) signaling pathway plays a key role in periodontitis by modulating redox balance and inflammation of the periodontium. However, NRF2 expression is decreased in gingival tissues of patients with periodontitis while oxidative stress is significantly increased in this pathology. Oxidative stress and lipopolysaccharide (LPS) produced by gram-negative bacteria favor the production of inflammatory causing periodontal inflammation and favoring alveolar bone. In this review, we analyzed the current literature regarding the role of natural and synthetic compounds in modulating the NRF2/KEAP1 pathway in in vitro and in vivo models of periodontitis in order to evaluate new potential treatments of periodontitis that can improve the outcome of this disease.

Mechanisms of action of mineral fibres in a placental syncytiotrophoblast model: An in vitro toxicology study.

Asbestos has been widely used due to its unique characteristics. It is known that exposure to asbestos causes serious damage to health but one species, chrysolite, is still used because it is considered less toxic and not biopersistent in some countries. The aim of our study was to investigate if cellular process underlying the proliferation, differentiation and cell death of placental tissues could be modify in presence of asbestos fibres (50 µg/ml final concentration), long chrysolite fibres (CHR-L) and short chrysolite fibres (CHR-S), using BeWo cell line, an in vitro model that mimics the syncytiotrophoblast (STB), the outer layer of placental villi. Our data demonstrated that none of the fibres analysed alter syncytiotrophoblast formation but all of them induce ROS formation and reduced cell proliferation. Moreover, we showed that only CHR-L fibre induced was able to induce irreversible DNA alterations that carried cells to apoptosis. In fact, BeWo cells exposed to CHR-L fibre showed a significant increase in cleaved CASP3 protein, a marker of apoptosis. These data suggest that CHR-L may induce death of the placental villi leading to impaired placental development. The impairment of placental development is the basis of many gestational pathologies such as preeclampsia and intrauterine growth retardation. Since these pathologies are very dangerous for foetal and maternal life, we suggest to the gynaecologists to carefully evaluate the area of maternal residence, the working environment, the food used, and the materials used daily to avoid contact with these fibres as much as possible.

Role of SLC7A11/xCT in Ovarian Cancer.

Ovarian cancer is one of the most dangerous gynecologic cancers worldwide and has a high fatality rate due to diagnosis at an advanced stage of the disease as well as a high recurrence rate due to the occurrence of chemotherapy resistance. In fact, chemoresistance weakens the therapeutic effects, worsening the outcome of this pathology. Solute Carrier Family 7 Member 11 (SLC7A11, also known as xCT) is the functional subunit of the Xc- system, an anionic L-cystine/L-glutamate antiporter expressed on the cell surface. SLC7A11 expression is significantly upregulated in several types of cancers in which it can inhibit ferroptosis and favor cancer cell proliferation, invasion and chemoresistance. SLC7A11 expression is also increased in ovarian cancer tissues, suggesting a possible role of this protein as a therapeutic target. In this review, we provide an overview of the current literature regarding the role of SLC7A11 in ovarian cancer to provide new insights on SLC7A11 modulation and evaluate the potential role of SLC7A11 as a therapeutic target.

First Trimester CD93 as a Novel Marker of Preeclampsia and Its Complications: A Pilot Study.

INTRODUCTION: CD93 plays a crucial role in endothelial homeostasis and angiogenesis. Recently its role in hypertension has been investigated, holding promise for novel targeted diagnostic and therapeutic strategies. AIM: We assessed for the first time differences in first trimester serum CD93 levels in women who lately developed preeclampsia (PE) vs. normotensive pregnancy (NP). METHODS: First trimester serum CD93 concentrations were assessed in a multicenter cohort of 83 women (34 PE and 49 NP) by ELISA Immunoassay. RESULTS: Serum CD93 was lower in women who developed PE vs. NP (111.8 ± 24.4 vs. 137.5 ± 22.3 ng/ml; p < 0.001). Serum CD93 was associated with a decreased risk of developing PE (OR 0.950, 95% CI 0.922-0.978) and composite neonatal outcome (OR 0.952, CI 0.923-0.982), after adjustment for confounders. CONCLUSIONS: PE is accompanied by decreased serum CD93 levels. CD93 might play a role during placentation leading to defective angiogenesis, vascular dysfunction, and PE development.

Cellular Modulators of the NRF2/KEAP1 Signaling Pathway in Prostate Cancer.

Prostate cancer is the second most common malignancy in men worldwide. Prostate cancer can be treated by surgery, radiotherapy and hormone therapy. The latter, in the form of androgen-deprivation therapy is needed to reduce prostate cancer progression at an advanced stage. Several studies demonstrated that oxidative stress is involved in cancer occurrence, development and progression and the Nuclear factor erythroid 2-related factor 2 (NRF2)/Kelch Like ECH Associated Protein 1 (KEAP1) pathway is affected by reactive oxygen species (ROS). Furthermore, the NRF2/KEAP1 signaling pathway has been investigated by several studies related to anti-androgen therapy, biochemical recurrence and radiotherapy. In this review we analysed the current literature regarding the indirect modulators involved in NRF2/KEAP1 pathway regulation and their role as possible therapeutic targets in prostate cancer cells.

Melanoma and subcutaneous adipose tissue: Role of peritumoral adipokines in disease characterization and prognosis.

In the last decades, the concept of adipose organ has emerged, giving adipose tissue an active endocrine and immunologic function through the secretion of multiple cytokines and chemokines that seem to be implicated in the development and progression of several cancer, including cutaneous melanoma. In this pilot experimental study, we analyzed the expression in the peritumor subcutaneous adipose tissue of the most significant adipokines involved in the processes of carcinogenesis and metastasis in a population of melanoma patients and in two control groups composed of melanocytic nevi and epidermoid cysts, respectively. We correlated the results obtained with the main disease prognostic factors observing a statistically significant increase in the expression of PAI1, LEP, CXCL1, NAMPT, and TNF-α at the level of the peritumor tissue of the melanoma samples compared to the control groups and a correlation of the same with the histopathological prognostic factor of melanoma. Our preliminary study shows that the overexpression of PAI1, LEP, CXCL1, NAMPT, and TNF-α may contribute to the growth and to the local aggressiveness of cutaneous melanoma. It opens the hypothesis of a direct oncogenic role of subcutaneous adipose tissue and adipokines in the tumorigenesis of melanoma.

Modulation of NRF2/KEAP1 Signaling in Preeclampsia.

Placentation is a key and tightly regulated process that ensures the normal development of the placenta and fetal growth. Preeclampsia (PE) is a hypertensive pregnancy-related disorder involving about 5-8% of all pregnancies and clinically characterized by de novo maternal hypertension and proteinuria. In addition, PE pregnancies are also characterized by increased oxidative stress and inflammation. The NRF2/KEAP1 signaling pathway plays an important role in protecting cells against oxidative damage due to increased reactive oxygen species (ROS) levels. ROS activate NRF2, allowing its binding to the antioxidant response element (ARE) region present in the promoter of several antioxidant genes such as heme oxygenase, catalase, glutathione peroxidase and superoxide dismutase that neutralize ROS, protecting cells against oxidative stress damages. In this review, we analyze the current literature regarding the role of the NRF2/KEAP1 pathway in preeclamptic pregnancies, discussing the main cellular modulators of this pathway. Moreover, we also discuss the main natural and synthetic compounds that can regulate this pathway in in vivo and in vitro models.

Role of Natural and Synthetic Compounds in Modulating NRF2/KEAP1 Signaling Pathway in Prostate Cancer.

Prostate cancer is the second most common cancer in men worldwide. Prostate cancer can be treated by surgery or active surveillance when early diagnosed but, when diagnosed at an advanced or metastatic stage, radiation therapy or androgen-deprivation therapy is needed to reduce cancer progression. However, both of these therapies can cause prostate cancer resistance to treatment. Several studies demonstrated that oxidative stress is involved in cancer occurrence, development, progression and treatment resistance. The nuclear factor erythroid 2-related factor 2 (NRF2)/KEAP1 (Kelch-Like ECH-Associated Protein 1) pathway plays an important role in protecting cells against oxidative damage. Reactive oxygen species (ROS) levels and NRF2 activation can determine cell fate. In particular, toxic levels of ROS lead physiological cell death and cell tumor suppression, while lower ROS levels are associated with carcinogenesis and cancer progression. On the contrary, a high level of NRF2 promotes cell survival related to cancer progression activating an adaptive antioxidant response. In this review, we analyzed the current literature regarding the role of natural and synthetic compounds in modulating NRF2/KEAP1 signaling pathway in prostate cancer.

HTRA1 in Placental Cell Models: A Possible Role in Preeclampsia.

The HtrA serine peptidase 1 (HTRA1) is a multidomain secretory protein with serine-protease activity involved in the regulation of many cellular processes in both physiological and pathological conditions. HTRA1 is normally expressed in the human placenta, and its expression is higher in the first trimester compared to the third trimester, suggesting an important role of this serine protease in the early phases of human placenta development. The aim of this study was to evaluate the functional role of HTRA1 in in vitro models of human placenta in order to define the role of this serine protease in preeclampsia (PE). BeWo and HTR8/SVneo cells expressing HTRA1 were used as syncytiotrophoblast and cytotrophoblast models, respectively. Oxidative stress was induced by treating BeWo and HTR8/SVneo cells with H2O2 to mimic PE conditions in order to evaluate its effect on HTRA1 expression. In addition, HTRA1 overexpression and silencing experiments were performed to evaluate the effects on syncytialization, cell mobility, and invasion processes. Our main data showed that oxidative stress significantly increased HTRA1 expression in both BeWo and HTR8/SVneo cells. In addition, we demonstrated that HTRA1 has a pivotal role in cell motility and invasion processes. In particular, HTRA1 overexpression increased while HTRA1 silencing decreased cell motility and invasion in HTR8/SVneo cell model. In conclusion, our results suggest an important role of HTRA1 in regulating extravillous cytotrophoblast invasion and motility during the early stage of placentation in the first trimester of gestation, suggesting a key role of this serine protease in PE onset.

The Role of NQO1 in Ovarian Cancer.

Ovarian cancer is one of the most dangerous gynecologic malignancies showing a high fatality rate because of late diagnosis and relapse occurrence due to chemoresistance onset. Several researchers reported that oxidative stress plays a key role in ovarian cancer occurrence, growth and development. The NAD(P)H:quinone oxidoreductase 1 (NQO1) is an antioxidant enzyme that, using NADH or NADPH as substrates to reduce quinones to hydroquinones, avoids the formation of the highly reactive semiquinones, then protecting cells against oxidative stress. In this review, we report evidence from the literature describing the effect of NQO1 on ovarian cancer onset and progression.

Downregulation of argininosuccinate synthase 1 (ASS1) is associated with hypoxia in placental development.

Argininosuccinate synthase (ASS1) is involved in nitric oxide production, which has a key role in placental development improving pregnancy outcomes. Syncytiotrophoblast and extravillous trophoblast differentiations are milestones of placental development and their impairment can cause pathologies, such as preeclampsia (PE) and fetal growth restriction (FGR). Immunohistochemistry and Western blotting were used to localize and quantify ASS1 in first trimester (8.2 ± 1.8 weeks), third trimester (38.6 ± 1.1 weeks), and PE (36.3 ± 1.5 weeks) placentas. In addition, cell cultures were used to evaluate ASS1 expression under hypoxic conditions and the syncytialization process. Our data showed that ASS1 is localized in the villous cytotrophoblast of first trimester, third trimester, and PE placentas, while the villous cytotrophoblast adjacent to the extravillous trophoblast of cell columns as well as the extravillous trophoblast were negative for ASS1 in first trimester placentas. In addition, ASS1 was decreased in third trimester compared to the first trimester placentas (p = 0.003) and no differences were detected between third trimester and PE placentas. Moreover, ASS1 expression was decreased in hypoxic conditions and syncytialized cells compared to those not syncytialized. In conclusion, we suggest that the expression of ASS1 in villous cytotrophoblast is related to maintaining proliferative phenotype, while ASS1 absence may be involved in promoting the differentiation of villous cytotrophoblast in extravillous cytotrophoblast of cell columns in first trimester placentas.

ZO-1 expression in normal human macula densa: Immunohistochemical and immunofluorescence investigations.

The macula densa (MD) is an anatomical structure having a plaque shape, placed in the distal end of thick ascending limb of each nephron and belonging to juxtaglomerular apparatus (JGA). The aim of the present investigation is to investigate the presence of ZO-1, a specific marker of tight juncions (TJs), in MD cells. Six samples of normal human renal tissue were embedded in paraffin for ZO-1 expression analysis by immunohistochemical and immunofluorescence techniques. We detected ZO-1 expression in the apical part of cell membrane in MD cells by immunohistochemistry. In addition, ZO-1 and nNOS expressions (a specific marker of MD) were colocalized in MD cells providing clear evidence of TJs presence in normal human MD. Since ZO-1 is responsible for diffusion barrier formation, its presence in the MD supports the existence of a tubulomesangial barrier that ensures a regulated exchange between MD and JGA effectors in renal and glomerular haemodynamic homeostasis.

NRF2 modulation in TRAMP mice: an in vivo model of prostate cancer.

BACKGROUND: Prostate cancer (PCa) is one of the most common cancers worldwide and oxidative stress is involved in its occurrence, development and progression. In fact, in transgenic adenocarcinoma of mouse prostate (TRAMP) mice, prostate cancer onset is associated with the methylation of the first five CpG in the nuclear factor erythroid 2-related factor 2 (NRF2) promoter, a key regulator of oxidative stress response, leading to its downregulation and accumulation of reactive oxygen species (ROS). It has been demonstrated that both natural and synthetic compounds can reactivate NRF2 expression inhibiting the methylation status of its promoter by downregulation of DNA methyltransferases (DNMTs) and histone deacetylases (HDACs). Interestingly, NRF2 re-expression significantly reduced prostate cancer onset in TRAMP mice highlighting an important role of NRF2 in prostate tumorigenesis. METHODS AND RESULTS: We analysed the current literature regarding the role of natural and synthetic compounds in modulating NRF2 pathway in TRAMP mice, an in vivo model of prostate cancer, to give an overview on prostate carcinogenesis and its possible prevention. CONCLUSION: We can conclude that specific natural and synthetic compounds can downregulate DNMTs and/or HDACs inhibiting the methylation status of NRF2 promoter, then reactivating the expression of NRF2 protecting normal prostatic cells from ROS damage and tumorigenesis.

Ciliary Neurotrophic Factor Modulates Multiple Downstream Signaling Pathways in Prostate Cancer Inhibiting Cell Invasiveness.

BACKGROUND: Prostate cancer (PCa) remains the most common diagnosed tumor and is the second-leading cause of cancer-related death in men. If the cancer is organ-confined it can be treated by various ablative therapies such as RP (radical prostatectomy), RT (radiation therapy), brachytherapy, cryosurgery or HIFU (High-Intensity Focused Ultrasound). However, advanced or metastatic PCa treatment requires systemic therapy involving androgen deprivation, but such patients typically progress to refractory disease designated as castration-resistant prostate cancer (CRPC). Interleukin-6 (IL-6) has been established as a driver of prostate carcinogenesis and tumor progression while less is known about the role of ciliary neurotrophic factor (CNTF), a member of the IL-6 cytokine family in prostate cancer. Moreover, MAPK/ERK, AKT/PI3K and Jak/STAT pathways that regulate proliferative, invasive and glucose-uptake processes in cancer progression are triggered by CNTF. METHODS: We investigate CNTF and its receptor CNTFRα expressions in human androgen-responsive and castration-resistant prostate cancer (CRPC) by immunohistochemistry. Moreover, we investigated the role of CNTF in proliferative, invasive processes as well as glucose uptake using two cell models mimicking the PCa (LNCaP cell line) and CRPC (22Rv1 cell line). CONCLUSIONS: Our results showed that CNTF and CNTFRa were expressed in PCa and CRPC tissues and that CNTF has a pivotal role in prostate cancer environment remodeling and as a negative modulator of invasion processes of CRPC cell models.

HtrA1 in Gestational Diabetes Mellitus: A Possible Biomarker?

BACKGROUND: The high-temperature requirement A 1 (HtrA1) is a multidomain secretory protein with serine-protease activity, expressed in many tissues, including placenta, where its expression is higher in the first trimester, suggesting an association of this serine protease in early phases of human placenta development. In this study, we evaluated maternal serum HtrA1 levels in the first and third trimester of gestation. In particular, we evaluated a possible role of HtrA1 as an early marker of gestational diabetes mellitus (GDM) in the first trimester of gestation. METHODS: We evaluated HtrA1 serum levels in the third trimester (36-40 weeks) in normal pregnancies (n = 20) and GDM pregnancies (n = 20) by using ELISA analysis. Secondly, we performed the same analysis by using the first trimester sera (10-12 weeks) of healthy pregnant women that will develop a normal pregnancy (n = 210) or GDM (n = 28) during pregnancy. RESULTS: We found that HtrA1 serum levels in the third trimester were higher in pregnancies complicated by GDM. Interestingly, higher HtrA1 serum levels were also found in the first trimester in women developing GDM later during the second-third trimester. No significant differences in terms of maternal age and gestational age were found between cases and controls. Women with GDM shown significantly higher pre-pregnancy BMI values compared to controls. Moreover, the probability of GDM occurrence significantly increased with increasing HtrA1 levels and BMI values. The ROC curve showed a good accuracy in predicting GDM, with an AUC of 0.74 (95%CI: 0.64-0.92). CONCLUSIONS: These results suggest an important role of HtrA1 as an early predictive marker of GDM in the first trimester of gestation, showing a significative clinical relevance for prevention of this disease.

Scattered Tubular Cells Markers in Macula Densa of Normal Human Adult Kidney.

BACKGROUND: The scattered tubular cells (STCs) are a population of resident progenitor tubular cells with expansion, self-renewal and epithelial differentiation abilities. Although these cells are localized within the proximal (PTs) and distal (DTs) tubules in a normal adult kidney, their presence has never been demonstrated in human macula densa (MD). The purpose of the present study is to describe the presence of STCs in MD using specific markers such as prominin-1 (CD133), cytokeratin 7 (KRT7) and vimentin (VIM). METHODS: We analyzed two sets of three consecutive serial sections for each sample. The first sections of each set were immunostained for nNOS to identify MD, the second sections were immune-stained for CD133 (specific STCs marker) while the third sections were analyzed for KRT7 (another STCs specific marker) and VIM (that stains the basal pole of the STCs) in the first and second sets, respectively, in order to study the co-expression of KRT7 and VIM with the CD133 marker. RESULTS: CD133 was localized in some MD cells and in the adjacent DT cells. Moreover, CD133 was detected in the parietal epithelial cells of Bowman's capsule and in some proximal tubules (PT). KRT7-positive cells were identified in MD and adjacent DT cells, while KRT7 positivity was mostly confined in both DT and collecting ducts (CD) in the other areas of the renal parenchyma. CD133 and KRT7 were co-expressed in some MD and adjacent DT cells. Some of the latter cells were positive both for CD133 and VIM. CD133 was always localized in the apical part of the cells, whereas the VIM expression was evident only in the cellular basal pole. Although some cells of MD expressed VIM or CD133, none of them co-expressed VIM and CD133. CONCLUSIONS: The presence of STCs was demonstrated in human adult MD, suggesting that this structure has expansion, self-renewal and epithelial differentiation abilities, similar to all other parts of renal tubules.

Preeclampsia and severe acute respiratory syndrome coronavirus 2 infection: a systematic review.

OBJECTIVE: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the coronavirus disease 2019 (COVID-19) disease that has rapidly spread worldwide, causing hundreds of thousand deaths. Normal placentation is characterized by many processes strictly regulated during pregnancy. If placentation is impaired, it can lead to gestational disorders, such as preeclampsia that is a multisystem disorder that occurs in 2-8% of pregnancies worldwide. METHODS: We performed a systematic search to understand the potential involvement of SARS-CoV-2 in preeclampsia onset using the databases, PubMed and Web of Science until 31 January 2022. RESULTS: SARS-CoV-2 infection not only causes damage to the respiratory system but also can infect human placenta cells impairing pivotal processes necessary for normal placenta development. The inflammatory response trigged by COVID-19 disease is very similar to that one found in preeclampsia pregnancies suggesting a possible link between SARS-CoV-2 infection and preeclampsia onset during pregnancy. CONCLUSION: Some studies showed that pregnancies affected by COVID-19 had higher incidence of preeclampsia compared with SARS-CoV-2-negative ones. However, increased blood pressure found in COVID-19 pregnancies does not allow to associate COVID-19 to preeclampsia as hypertension is a common factor to both conditions. At present, no diagnostic tools are available to discriminate real preeclampsia from preeclampsia-like syndrome in patients with SARS-CoV-2 infection. Thus, new specific diagnostic tools are necessary to assure an appropriate diagnosis of preeclampsia in these patients, especially in case of severe COVID-19 disease.

Modulation of matrix metalloproteases by ciliary neurotrophic factor in human placental development.

Ciliary neurotrophic factor (CNTF) is a pleiotropic cytokine that signals through a receptor complex containing a specific subunit, CNTF receptor α (CNTFRα). The two molecules are constitutively expressed in key structures for human placental growth and differentiation. The possible role of CNTF in enhancing cell proliferation and/or invasion during placental development and remodelling was investigated using HTR-8/SVneo and BeWo cells, taken respectively as cytotrophoblast and syncytiotrophoblast models. In both cell lines, treatment with human recombinant (hr) CNTF activated JAK2/STAT3 signalling and inhibited the ERK pathway. Interestingly, in HTR-8/SVneo cells, 50 ng hrCNTF induced significant downregulation of matrix metalloprotease (MMP)-1 and significant upregulation of MMP-9. Moreover, pharmacological inhibition of JAK2/STAT3 signalling by AG490 and curcumin resulted in MMP-9 downregulation; it activated the ERK signalling pathway and upregulated MMP-1 expression. Collectively, these data suggest a role for CNTF signalling in extravillous cytotrophoblast invasion through the modulation of specific MMPs.

Role of NRF2 in Ovarian Cancer.

Among gynaecologic malignancies, ovarian cancer is one of the most dangerous, with a high fatality rate and relapse due to the occurrence of chemoresistance. Many researchers demonstrated that oxidative stress is involved in tumour occurrence, growth and development. Nuclear factor erythroid 2-related factor 2 (NRF2) is an important transcription factor, playing an important role in protecting against oxidative damage. Increased levels of Reactive Oxygen Species (ROS) activate NRF2 signalling, inducing the expression of antioxidant enzymes, such as haem oxygenase (HO-1), catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD), that protect cells against oxidative stress. However, NRF2 activation in cancer cells is responsible for the development of chemoresistance, inactivating drug-mediated oxidative stress that normally leads to cancer cells' death. In this review, we report evidence from the literature describing the effect of NRF2 on ovarian cancer, with a focus on its function in drug resistance, NRF2 natural and synthetic modulators and its protective function in normal ovarian preservation.