Bacterial Lipopolysaccharides Induce Steroid Sulfatase Expression and Cell Migration through IL-6 Pathway in Human Prostate Cancer Cells

Metabolic Fingerprinting of Feces from Calves, Subjected to Gram-Negative Bacterial Endotoxin

Gram-negative bacteria have a well-known impact on the disease state of neonatal calves and their mortality. This study was the first to implement untargeted metabolomics on calves’ fecal samples to unravel the effect of Gram-negative bacterial endotoxin lipopolysaccharide (LPS). In this context, calves were challenged with LPS and administered with fish oil, nanocurcumin, or dexamethasone to evaluate treatment effects. Ultra-high-performance liquid-chromatography high-resolution mass spectrometry (UHPLC-HRMS) was employed to map fecal metabolic fingerprints from the various groups before and after LPS challenge. Based on the generated fingerprints, including 9650 unique feature ions, significant separation according to LPS group was achieved through orthogonal partial least squares discriminant analysis (Q² of 0.57 and p-value of 0.022), which allowed the selection of 37 metabolites as bacterial endotoxin markers. Tentative identification of these markers suggested that the majority belonged to the subclass of the carboxylic acid derivatives—amino acids, peptides, and analogs—and fatty amides, with these subclasses playing a role in the metabolism of steroids, histidine, glutamate, and folate. Biological interpretations supported the revealed markers’ potential to aid in disease diagnosis, whereas beneficial effects were observed following dexamethasone, fish oil, and nanocurcumin treatment.

Human steroid sulfatase enhances aerobic glycolysis through induction of HIF1α and glycolytic enzymes

Human steroid sulfatase (STS) has been linked with poor prognosis in steroid-associated tumors and represents an important clinical target in cancers, yet the mechanism of STS-induced carcinogenesis remains unclear. To correlate STS with cancer metabolism, we determined the effects of STS on aerobic glycolysis. STS overexpression increased cellular levels of lactic acid, the final product of aerobic glycolysis. Moreover, STS suppressed the oxygen consumption rate (OCR), which represents mitochondrial respiration. Inhibition of STS by the specific inhibitor STX064 recovered STS-induced OCR repression and lactic acid over-production. DHEA, but not DHEA-S, suppressed the OCR level and enhanced lactic acid production. To understand the molecular mechanism of STS-induced cancer metabolism, we measured the expression of glycolytic enzymes hexokinase 2 (HK2) and pyruvate kinase M2 (PKM2), which was highly upregulated by STS and DHEA at both protein and mRNA levels. HIF1α is a key mediator of aerobic glycolysis, and STS enhanced HIF1α promoter activity, mRNA expression, and protein expression. Down-regulation of HIF1α by siRNA suppressed the HK2 and PKM2 expression induced by both STS and DHEA. HIF1α siRNA also recovered the OCR repression and lactic acid over-production induced by both STS and DHEA. To explore the mechanism in vivo, we produced transgenic mice overexpressing STS and found that STS expression was particularly enhanced in the lung. Consistent with our in vitro results, the expression of HIF1α, HK2, and PKM2 was also increased in mouse lung tissues. In conclusion, we suggest that STS may induce aerobic glycolysis through enhancing HIF1α expression.

microRNA-211-3p has a Role in the Effects of Lipopolysaccharide on Endoplasmic Reticulum Stress in Cultured Human Skin Fibroblasts

Background

Lipopolysaccharide (LPS) in bacterial infection of skin wounds delays wound healing. This study aimed to investigate the effects of LPS and endoplasmic reticulum stress in cultured skin fibroblasts and microRNA-211-3p (miR-211-3p) signaling.

Material/Methods

Human skin fibroblasts were cultured in increasing concentrations of LPS at 0 ng/ml, 5 ng/ml, 10 ng/ml, and 20 ng/ml for 0, 12 h, 24 h, 36 h, and 48 h. Cell proliferation was determined using the MTT assay. Protein expression levels of the transcription factors GRP78, CHOP, p-JNK, and the endoplasmic reticulum stress apoptosis proteins, caspase-12 and Bcl-2, were determined by Western blot. The expression of miR-211-3p in human skin fibroblasts was detected by quantitative polymerase chain reaction (qPCR).

Results

Cell proliferation of human skin fibroblasts decreased with increasing concentrations of LPS in a dose-dependent and time-dependent way. Protein levels of GRP78, CHOP, p-JNK, caspase-12, and Bcl-2 were increased 8 h and 12 h after LPS treatment compared with 0 h and 4 h after treatment. However, the expression of miR-211-3p was decreased in human skin fibroblasts after treatment with LPS. When miR-211-3p was overexpressed, the endoplasmic reticulum stress/CHOP related proteins, including GRP78, CHOP, p-JNK, caspase-12, and Bcl-2 were unchanged after the addition of LPS. Overexpression of miR-211-3p also reduced inhibitory effects of LPS on the growth of human skin fibroblasts.

Conclusions

This study showed that microRNA-211-3p had a role in the effects of LPS on endoplasmic reticulum stress and CHOP activation in cultured human skin fibroblasts.

Estrogen receptor β suppresses inflammation and the progression of prostate cancer

Previous studies demonstrated that estrogen receptor β (ERβ) signaling alleviates systemic inflammation in animal models, and suggested that ERβ-selective agonists may deactivate microglia and suppress T cell activity via downregulation of nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB). In the present study, the role of ERβ in lipopolysaccharide (LPS)-induced inflammation and association with NF-κB activity were investigated in PC-3 and DU145 prostate cancer cell lines. Cells were treated with LPS to induce inflammation, and ELISA was performed to determine the expression levels of inflammatory cytokines, including tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein 1 (MCP-1), interleukin (IL)-1β and IL-6. MTT and Transwell assays, and Annexin V/propidium iodide staining were conducted to measure cell viability, apoptosis and migration, respectively. Protein expression was determined via western blot analysis. LPS-induced inflammation resulted in elevated expression levels of TNF-α, IL-1β, MCP-1 and IL-6 compared with controls. ERβ overexpression significantly inhibited the LPS-induced production of TNF-α, IL-1β, MCP-1 and IL-6. In addition, the results indicated that ERβ suppressed viability and migration, and induced apoptosis in prostate cancer cells, which was further demonstrated by altered expression of proliferating cell nuclear antigen, B-cell lymphoma 2-associated X protein, caspase-3, E-cadherin and matrix metalloproteinase-2. These effects were reversed by treatment with the ERβ antagonist PHTPP or ERβ-specific short interfering RNA. ERβ overexpression reduced the expression levels of p65 and phosphorylated NF-κB inhibitor α (IκBα), but not total IκBα expression in LPS-treated cells. In conclusion, ERβ suppressed the viability and migration of the PC-3 and DU145 prostate cancer cell lines and induced apoptosis. Furthermore, it reduced inflammation and suppressed the activation of the NF-κB pathway, suggesting that ERβ may serve roles as an anti-inflammatory and anticancer agent in prostate cancer.

Induction of Integrin Signaling by Steroid Sulfatase in Human Cervical Cancer Cells

Steroid sulfatase (STS) is an enzyme responsible for the hydrolysis of aryl and alkyl sulfates. STS plays a pivotal role in the regulation of estrogens and androgens that promote the growth of hormone-dependent tumors, such as those of breast or prostate cancer. However, the molecular function of STS in tumor growth is still not clear. To elucidate the role of STS in cancer cell proliferation, we investigated whether STS is able to regulate the integrin signaling pathway. We found that overexpression of STS in HeLa cells increases the protein and mRNA levels of integrin β1 and fibronectin, a ligand of integrin α5β1. Dehydroepiandrosterone (DHEA), one of the main metabolites of STS, also increases mRNA and protein expression of integrin β1 and fibronectin. Further, STS expression and DHEA treatment enhanced phosphorylation of focal adhesion kinase (FAK) at the Tyr 925 residue. Moreover, increased phosphorylation of ERK at Thr 202 and Tyr 204 residues by STS indicates that STS activates the MAPK/ERK pathway. In conclusion, these results suggest that STS expression and DHEA treatment may enhance MAPK/ERK signaling through up-regulation of integrin β1 and activation of FAK.

Anti-inflammatory effect of Varthemia iphionoides extracts against prostate cancer in vitro

Varthemia iphionoides is a Jordanian medicinal plant with several health-promoting properties, including antibacterial, antioxidant and anticancer activities. However, its anti-inflammatory properties have been poorly investigated up to date. The current study aimed to investigate the anti-inflammatory effect of V. iphionoides by measuring the production of interleukin-6 in response to a pro-inflammatory stimulus (bacterial lipopolysaccharide) in in vitro cell models of human MRC-5 and PC3 cells. We observed a significant reduction in lipopolysaccharide-induced interleukin-6 release in response to V. iphionoides (125 µg/mL) in both non-cancerous fibroblast MRC-5 and prostate cancerous PC3 cells. However, the anti-inflammatory effect of this medicinal plant was stronger when MRC-5 cells were treated with an aqueous extract, while the methanolic extract was more potent in PC3 cells. The effect of V. iphionoides in reducing interleukin-6 production was not due to its cytotoxicity, and future studies are required to elucidate the mechanisms of action by which this medicinal plant modulates inflammatory responses. In conclusion, the results of our study represent the first report of the potential protective effect of water and methanolic extracts of V. iphionoides against pro-inflammatory stimuli in fibroblasts and cancer cells of human origin, and it is critically important to identify the phytochemical compounds responsible for this effect.

3D Spheroid Culture Enhances the Expression of Antifibrotic Factors in Human Adipose-Derived MSCs and Improves Their Therapeutic Effects on Hepatic Fibrosis

Three-dimensional (3D) cell culture has been reported to increase the therapeutic potentials of mesenchymal stem cells (MSCs). However, the action mechanisms of 3D MSCs vary greatly and are far from being thoroughly investigated. In this study, we aimed to investigate the therapeutic effects of 3D spheroids of human adipose-derived MSCs for hepatic fibrosis. Our results showed that 3D culture enhanced the expression of antifibrotic factors by MSCs, including insulin growth factor 1 (IGF-1), interleukin-6 (IL-6), and hepatocyte growth factor (HGF). In vitro studies indicated conditioned medium of 3D cultured MSCs protected hepatocytes from cell injury and apoptosis more effectively compared with 2D cultured cells. More importantly, when transplanted into model mice with hepatic fibrosis, 3D spheroids of MSCs were more beneficial in ameliorating hepatic fibrosis and improving liver function than 2D cultured cells. Therefore, the 3D culture strategy improved the therapeutic effects of MSCs and might be promising for treatment of hepatic fibrosis.

Lipopolysaccharides attenuates growth of HS cells through the JNK pathway

Rheumatoid arthritis is characterized by inflammation of the synovial membrane, which can result in joint destruction within the first few years after onset. Lipopolysaccharides (LPS) are glycolipids found in abundance on the outer membranes of all Gram-negative bacteria and incite a vigorous inflammatory response. We studied the potential involvement of mitogen-activated protein kinase serine/threonine kinases in LPS-induced growth of HS synovial cells. Various concentrations of LPS were applied to cultured HS cells and growth rate, as well as changes in the phosphorylation states of extracellular regulated kinase 1/2, Jun N-terminal kinase (JNK), and p38 were determined. As results, growth of LPS-treated HS cells was inhibited primarily by phosphorylated JNK and this phosphorylation was mediated by the LPS receptor. Our results suggest that LPS inhibits growth of HS cells primarily through the JNK pathway.

Novel effects of FTY720 on perinuclear reorganization of keratin network induced by sphingosylphosphorylcholine: Involvement of protein phosphatase 2A and G-protein-coupled receptor-12

Sphingosylphosphorylcholine (SPC) evokes perinuclear reorganization of keratin 8 (K8) filaments and regulates the viscoelasticity of metastatic cancer cells leading to enhanced migration. Few studies have addressed the compounds modulating the viscoelasticity of metastatic cancer cells. We studied the effects of sphingosine (SPH), sphingosine 1-phosphate (S1P), FTY720 and FTY720-phosphate (FTY720P) on SPC-induced K8 phosphorylation and reorganization using Western blot and confocal microscopy, and also evaluated the elasticity of PANC-1 cells by atomic force microscopy. FTY720, FTY720P, SPH, and S1P concentration-dependently inhibited SPC-evoked phosphorylation and reorganization of K8, and migration of PANC-1 cells. SPC triggered reduction and narrow distribution of elastic constant K and conversely, FTY720 blocked them. A common upstream regulator of JNK and ERK, protein phosphatase 2A (PP2A) expression was reduced by SPC, but was restored by FTY720 and FTY72P. Butyryl forskolin, a PP2A activator, suppressed SPC-induced K8 phosphorylation and okadaic acid, a PP2A inhibitor, induced K8 phosphorylation. Gene silencing of PP2A also led to K8 phosphorylation, reorganization and migration. We also investigated the involvement of GPR12, a high-affinity SPC receptor, in SPC-evoked keratin phosphorylation and reorganization. GPR12 siRNA suppressed the SPC-triggered phosphorylation and reorganization of K8. GPR12 overexpression stimulated keratin phosphorylation and reorganization even without SPC. FTY720 and FTY720P suppressed the GPR12-induced phosphorylation and reorganization of K8. The collective data indicates that FTY720 and FTY720P suppress SPC-induced phosphorylation and reorganization of K8 in PANC-1 cells by restoring the expression of PP2A via GPR12. These findings might be helpful in the development of compounds that modulate the viscoelasticity of metastatic cancer cells and various SPC actions.

Steroid sulfatase in the human MG-63 preosteoblastic cell line: Antagonistic regulation by glucocorticoids and NFκB

Steroid sulfatase (STS) converts sulfated steroids into active forms in cells. Preosteoblastic cells possess STS, but its role and regulation in bone are unclear. We examined STS activity and gene expression during differentiation of human MG-63 preosteoblasts. STS activity and gene expression were decreased during differentiation in cells treated with osteogenic supplement containing dexamethasone (DEX). DEX also inhibited STS activity and expression in undifferentiated cells, and the glucocorticoid antagonist RU486 reversed DEX inhibition of STS. These data may have implications for glucocorticoid-induced osteoporosis. The NFκB activators lipopolysaccharide and phorbol myristate acetate increased STS expression in undifferentiated and differentiated MG-63 cells, while the NFκB inhibitor BAY-11-7082 partially blocked these responses. The antagonistic actions of glucocorticoids and NFkB on STS expression are similar to the regulation of inflammatory response proteins. We propose a model of STS regulation whereby inflammation leads to increased STS, resulting in increased estrogen, which modulates the inflammatory response.

Evidence of estrone-sulfate uptake modification in young and middle-aged rat prostate

High plasma exposure to estrogens is often associated with prostate cancer. Reducing this phenomenon may present therapeutic benefits. The involvement of estrone sulphate (E1S), the most abundant circulating estrogen in men, has been partially studied in this age-related pathology. To investigate the consequences of plasma E1S overload on blood and prostate sex steroid levels and inflammatory tissue responses, young and middle-aged male rats were treated with E1S with or without steroid sulfatase (STS) inhibitor STX64 for 21 consecutive days. A plasma and prostate tissue steroid profile was determined. STS activity, mRNA expression of E1S organic anion transporting polypeptides (slco1a2, slco2b1, slco4a1) and pro-inflammatory cytokines (Il1-beta, Il6, TNF-alpha) were evaluated in prostate tissue according to age and treatment group. A significant correlation between plasma and prostate steroid levels related to hormone treatment was observed in all rat age groups. However, while the E1S level in prostate tissue increased in middle-aged treated rats (p<0.0001), no significant variation was observed in young treated rats. The protective effect of STX64 during E1S infusion was observed by the maintenance of low free estrogen concentrations in both plasma and tissue. However, this protection was not associated with mRNA expression stability of pro-inflammatory cytokines in older rat prostate. These results suggest that E1S uptake in rat prostate cells increases during aging. Therefore, if a similar phenomenon existed in men, preventively reducing the STS activity could be of interest to limit uptake of estrogens in prostate when high E1S plasma level is assayed.

Syk/Src-targeted anti-inflammatory activity of Codariocalyx motorius ethanolic extract

ETHNOPHARMACOLOGICAL RELEVANCE

Codariocalyx motorius (Houtt.) H. Ohashi (Fabaceae) is one of several ethnopharmacologically valuable South Asian species prescribed as an herbal medicine for various inflammatory diseases. Due to the lack of systematic studies on this plant, we aimed to explore the inhibitory activity of Codariocalyx motorius toward inflammatory responses using its ethanolic extract (Cm-EE).

MATERIALS AND METHODS

Lipopolysaccharide (LPS)-treated macrophages and a HCl/EtOH-induced gastritis model were used for evaluation of the anti-inflammatory activity of Cm-EE. HPLC and spectroscopic analysis were employed to identify potential active components. Mechanistic approaches to determine target enzymes included kinase assays, reporter gene assays, and overexpression of target enzymes.

RESULTS

Cm-EE strongly suppressed nitric oxide (NO) and prostaglandin E2 (PGE2) release. Cm-EE-mediated inhibition was observed at the transcriptional level in the form of suppression of NF-κB (p65) translocation and activation. This extract also lowered the levels of phosphorylation of Src and Syk, their kinase activity, and their formation of signalling complexes by binding to the downstream enzyme p85/PI3K. In accord with these findings, the phosphorylation of p85 induced by overexpression of Src or Syk was also diminished by Cm-EE. Orally administered Cm-EE clearly inhibited gastritic ulcer formation and the phosphorylation of IκBα and Src in HCl/EtOH-treated stomachs of mice. By phytochemical analysis, luteolin and its glycoside, apigenin-7-O-glucuronide, and scutellarein-6-O-glucuronide were identified as major components of Cm-EE. Among these, it was found that luteolin was able to strongly suppress NO and PGE2 production under the same conditions.

CONCLUSION

Syk/Src-targeted inhibition of NF-κB by Cm-EE could be a major anti-inflammatory mechanism contributing to its ethno pharmacological role as an anti-inflammatory herbal medicine.

Myrsine seguinii ethanolic extract and its active component quercetin inhibit macrophage activation and peritonitis induced by LPS by targeting to Syk/Src/IRAK-1

ETHNOPHARMACOLOGICAL RELEVANCE

Myrsine seguinii H. LÉVEILLÉ (syn. Rapanea neriifolia) (Myrsinaceae) is a medicinal plants traditionally used in Myanmar to treat infectious and inflammatory diseases. Since none of reports have systematically demonstrated the anti-inflammatory activity of this plant, we aimed to mechanistically understand the regulatory roles of the plant in inflammatory responses using the ethanolic extract of Myrsine seguinii (Ms-EE).

MATERIALS AND METHODS

Activated macrophages and peritonitis symptoms induced by lipopolysaccharide (LPS) were employed. HPLC analysis was used to identify active components. To characterize direct target enzymes, kinase assay was established.

RESULTS

Ms-EE inhibited the production of nitric oxide (NO) and prostaglandin (PG)E2 in RAW264.7 cells and peritoneal macrophages stimulated by LPS. This extract suppressed the mRNA expression of the inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 genes by down-regulating the activation of nuclear factor (NF)-κB and activator protein (AP-1). Interestingly, it was found that Ms-EE can directly suppress the enzyme activities of Syk, Src, and interleukin-1 receptor-associated kinase-1 (IRAK-1). Similarly, orally administered Ms-EE inhibited the phosphorylation of Src and Syk in peritoneal exudate-derived cells prepared from peritonitis. Finally, HPLC analysis clearly demonstrated that quercetin is a major active component with suppressing activity on the release of inflammatory mediators (NO and PGE2), and the enzyme activities of Src, Syk, and IRAK-1.

CONCLUSION

Ms-EE containing quercetin negatively modulates macrophage-mediated in vitro inflammatory responses and LPS-induced peritonitis by blocking the Src/Syk/NF-κB and IRAK-1/AP-1 pathways, which contributes to its major ethnopharmacological use as an anti-inflammatory herbal medicine.

Induction of steroid sulfatase expression in PC-3 human prostate cancer cells by insulin-like growth factor II

Human steroid sulfatase (STS) plays an important role in regulating the formation of biologically active estrogens and may be a promising target for treating estrogen-mediated carcinogenesis. The molecular mechanism of STS gene expression, however, is still not clear. Growth factors are known to increase STS activity but the changes in STS expression have not been completely understood. To determine whether insulin-like growth factor (IGF)-II can induce STS gene expression, the effects of IGF-II on STS expression were studied in PC-3 human prostate cancer cells. RT-PCR and Western blot analysis showed that IGF-II treatment significantly increased the expression of STS mRNA and protein in concentration- and time-dependent manners. To understand the signaling pathway by which IGF-II induces STS gene expression, the effects of specific PI3-kinase/Akt and NF-κB inhibitors were determined. When the cells were treated with IGF-II and PI3-kinase/Akt inhibitors, such as LY294002, wortmannin, or Akt inhibitor IV, STS expression induced by IGF-II was significantly blocked. Moreover, we found that NF-κB inhibitors, such as MG-132, bortezomib, Bay 11-7082 or Nemo binding domain (NBD) binding peptide, also strongly prevented IGF-II from inducing STS gene expression. We assessed whether IGF-II activates STS promoter activity using transient transfection with a luciferase reporter. IGF-II significantly stimulated STS reporter activity. Furthermore, IGF-II induced expression of 17β-hydroxysteroid dehydrogenase (HSD) 1 and 3, whereas it reduced estrone sulfotransferase (EST) gene expression, causing enhanced estrone and β-estradiol production. Taken together, these results strongly suggest that IGF-II induces STS expression via a PI3-kinase/Akt-NF-κB signaling pathway in PC-3 cells and may induce estrogen production and estrogen-mediated carcinogenesis.