TRAF6 promotes spinal microglial M1 polarization to aggravate neuropathic pain by activating the c-JUN/NF-kB signaling pathway.

BACKGROUND: The neuropathic pain with complex networks of neuroinflammatory activation severely limits clinical therapeutic research. TNF receptor-associated factor 6 (TRAF6) is associated with multiple inflammatory diseases. However, there remains confusion about the effects and mechanisms of TRAF6 in neuropathic pain. METHODS: A chronic constriction injury (CCI) model was developed to simulate neuralgia in vivo. We overexpressed or knocked down TRAF6 in CCI mice, respectively. Activation of microglia by TRAF6, the inflammatory response, and disease progression were inspected using WB, qRT-PCR, immunofluorescence, flow cytometry, and ELISA assays. Moreover, the mechanism of M1/M2 polarization activation of microglia by TRAF6 was elaborated in BV-2 cells. RESULTS: TRAF6 was enhanced in the spinal neurons and microglia of the CCI mice model compared with the sham operation group.. Down-regulation of TRAF6 rescued the expression of Iba-1. In response to mechanical and thermal stimulation, PWT and PWL were improved after the knockdown of TRAF6. Decreased levels of pro-inflammatory factors were observed in TRAF6 knockdown groups. Meanwhile, increased microglial M1 markers induced by CCI were limited in mice with TRAF6 knockdown. In addition, TRAF6 overexpression has the precise opposite effect on CCI mice or microglia polarization. We also identifed that TRAF6 activated the c-JUN/NF-kB pathway signaling; the inhibitor of c-JUN/NF-kB could effectively alleviate the neuropathic pain induced by upregulated TRAF6 in the CCI mice model. CONCLUSION: In summary, this study indicated that TRAF6 was concerned with neuropathic pain, and targeting the TRAF6/c-JUN/NF-kB pathway may be a prospective target for treating neuropathic pain.

Molecular signaling and mechanisms of low-level laser-induced gene expression in cells involved in orthodontic tooth movement.

BACKGROUND: The study aimed to observe molecular signaling, including reactive oxygen species (ROS) and mitochondrial membrane potential (ΔΨm), to evaluate the alteration of gene expression by low-level laser therapy (LLLT) and the correlation between its mechanisms and the NF-kB pathway in cells involved in orthodontic tooth movement. METHODS: Osteoblast-like cells (MG63), immortalized periodontal ligament cells (iPDL), and M1 macrophage-like cells were irradiated by 980-nm LLLT with energy densities of 1 and 10 J/cm2 ΔΨm and intracellular ROS were monitored using fluorescent probes. The changes of mRNA expression were assessed using reverse transcription polymerase chain reaction (RT-PCR). NF-kB inhibitor, ROS scavenger, and ΔΨm suppressor were used to analyze signals associated with the regulation of gene expression. Finally, Western blot analysis was performed to confirm NF-kB signaling after LLLT. RESULTS: We found the increases of ΔΨm and ROS in all three cell types after LLLT, but no significant difference was observed between 1 and 10 J/cm2 LLLT. Regarding gene expression, some target genes were upregulated in MG63 6 h, 12 h, and 1 day after LLLT and in iPDL cells 12 h and 1 day after LLLT. However, no changes occurred in M1 cells. The inhibitor that significantly reduced most changes in gene expression was NF-kB inhibitor. Western blot analysis showed the increase in p-IkBα level after LLLT in iPDL and MG63, but not in M1. CONCLUSION: The 980-nm LLLT increased ΔΨm and ROS production in all three cell types. However, changes in gene regulation were found only in MG63 and iPDL cells, which related to the NF-kB pathway.

Melittin Treats Periprosthetic Osteolysis in a Rat Model by Inhibiting the NF-kB Pathway and Regulating the Ratio of Receptor Activator of Nuclear Factor Kappa B Ligand/Osteoprotegerin.

BACKGROUND: Aseptic loosening around the prosthesis is a common cause of failure in total joint arthroplasty. Polyethylene wear particles trigger the release of inflammatory factors by macrophages. Key mediators involved in osteoclastogenesis include interleukin-6, tumor necrosis factor-α, receptor activator of nuclear factor kappa B (RANK), RANK ligand (RANKL), and bone protection hormone (Osteoprotegerin [OPG]). The purpose of our experiment was to see whether melittin can slow down the release of inflammatory mediators through the NF-kB pathway, regulate the RANKL/OPG ratio, reduce osteoclast formation, and delay the onset of arthritis in rats. METHODS: A total of 20 male Sprague-Dawley rats (10 months, Specific Pathogen Free, 350 g ± 20 g) were randomly divided into 5 groups: sham group, model group, melittin concentration 1 group (0.2 mg/kg), concentration 2 group (0.4 mg/kg), and concentration 3 group (0.6 mg/kg). All rats were implanted with TA2 high-purity titanium rods. A drill was used to create a bone canal along the long axis of the femur in the intercondylar notch. The model group and experimental groups were exposed to polyethylene particles, while the sham group did not receive any particles. RESULTS: The melittin group exhibited significantly increased serum levels of serum P, calcium-phosphorus product, OPG, PINP, PINP/CTX-I, and OPG/RANKKL (P < .05). In the experimental group, micro computed tomography scanning results revealed a decrease in the amount of bone defect around the prosthesis. Immunofluorescence analysis demonstrated a decrease in the expression of IKKα and P65, while the expression of OPG showed an upward trend. Both Hematoxylin-Eosin and Tartrate-Resistant Acid Phosphatase staining revealed less osteoclast and inflammatory cell infiltration in bone resorption pits. CONCLUSIONS: Our study demonstrates that melittin has the ability to inhibit the NF-kB pathway in a rat model, and reduce the impact of RANKL/OPG, thereby delaying osteoclast activity and alleviating periprosthetic osteolysis.

Kaempferol and Biomodified Kaempferol from Sophora japonica Extract as Potential Sources of Anti-Cancer Polyphenolics against High Grade Glioma Cell Lines.

The enzymatic hydrolysis of the extract of Sophora japonica by two glycosyl hydrolases (hesperidinase and galactosidase) was performed in order to obtain kaempferol (KPF)-enriched extract with an enhanced anticancer activity. The current study examined the effectiveness of both Sophora japonica extracts (before (KPF-BBR) and after (KPF-ABR) bioconversion reactions) in reducing cell viability and inducing apoptosis in human high-degree gliomas in vitro. Cytotoxicity was determined using an MTT assay. The effects of both compounds on the proliferation of glioma cell lines were measured using trypan blue exclusion, flow cytometry for cell cycle, wound healing (WH), and neurosphere formation assays. Cellular apoptosis was detected by DNA fragmentation and phosphatidylserine exposure. qPCR and luciferase assays evaluated NF-kB pathway inhibition. The survival rate of NG-97 and U-251 cells significantly decreased in a time- and dose-dependent manner after the addition of KPF-BBR or KPF-ABR. Thus, a 50% reduction was observed in NG-97 cells at 800 µM (KPF-BBR) and 600 µM (KPF-ABR) after 72 h. Both compounds presented an IC50 of 1800 µM for U251 after 72 h. The above IC50 values were used in all of the following analyses. Neither of the KPF presented significant inhibitory effects on the non-tumoral cells (HDFa). However, after 24 h, both extracts (KPF-BBR and KPF-ABR) significantly inhibited the migration and proliferation of NG-97 and U-251 cells. In addition, MMP-9 was downregulated in glioma cells stimulated by 12-O-tetradecanoylphorbol-13-acetate (TPA) plus KPF-BBR and TPA+KPF-ABR compared with the TPA-treated cells. Both KPF-BBR and KPF-ABR significantly inhibited the proliferation of glioma stem cells (neurospheres) after 24 h. DNA fragmentation assays demonstrated that the apoptotic ratio of KPF-ABR-treated cell lines was significantly higher than in the control groups, especially NG-97, which is not TMZ resistant. In fact, the flow cytometric analysis indicated that KPF-BBR and KPF-ABR induced significant apoptosis in both glioma cells. In addition, both KPF induced S and G2/M cell cycle arrest in the U251 cells. The qPCR and luciferase assays showed that both KPFs downregulated TRAF6, IRAK2, IL-1ß, and TNF-α, indicating an inhibitory effect on the NF-kB pathway. Our findings suggest that both KPF-BBR and KPF-ABR can confer anti-tumoral effects on human cell glioma cells by inhibiting proliferation and inducing apoptosis, which is related to the NF-κB-mediated pathway. The KPF-enriched extract (KPF-ABR) showed an increased inhibitory effect on the cell migration and invasion, characterizing it as the best antitumor candidate.

Dipotassium Glycyrrhizinate on Melanoma Cell Line: Inhibition of Cerebral Metastases Formation by Targeting NF-kB Genes-Mediating MicroRNA-4443 and MicroRNA-3620-Dipotassium Glycyrrhizinate Effect on Melanoma.

Glycyrrhizic acid (GA), a natural compound isolated from licorice (Glycyrrhiza glabra), has exhibited anti-inflammatory and anti-tumor effects in vitro. Dipotassium glycyrrhizinate (DPG), a dipotassium salt of GA, also has shown an anti-tumor effect on glioblastoma cell lines, U87MG and T98G. The study investigated the DPG effects in the melanoma cell line (SK-MEL-28). MTT assay demonstrated that the viability of the cells was significantly decreased in a time- and dose-dependent manner after DPG (IC50 = 36 mM; 24 h). DNA fragmentation suggested that DPG (IC50) induced cellular apoptosis, which was confirmed by a significant number of TUNEL-positive cells (p-value = 0.048) and by PARP-1 [0.55 vs. 1.02 arbitrary units (AUs), p-value = 0.001], BAX (1.91 vs. 1.05 AUs, p-value = 0.09), and BCL-2 (0.51 vs. 1.07 AUs, p-value = 0.0018) mRNA compared to control cells. The proliferation and wound-healing assays showed an anti-proliferative effect on DPG-IC50-treated cells, also indicating an inhibitory effect on cell migration (p-values < 0.001). Moreover, it was observed that DPG promoted a 100% reduction in melanospheres formation (p-value = 0.008). Our previous microRNAs (miRs) global analysis has revealed that DPG might increase miR-4443 and miR-3620 expression levels. Thus, qPCR showed that after DPG treatment, SK-MEL-28 cells presented significantly high miR-4443 (1.77 vs. 1.04 AUs, p-value = 0.02) and miR-3620 (2.30 vs. 1.00 AUs, p-value = 0.01) expression compared to control cells, which are predicted to target the NF-kB, CD209 and TNC genes, respectively. Both genes are responsible for cell attachment and migration, and qPCR revealed significantly decreased CD209 (1.01 vs. 0.54 AUs, p-value = 0.018) and TNC (1.00 vs. 0.31 AUs, p-value = 2.38 × 10−6) mRNA expression levels after DPG compared to untreated cells. Furthermore, the migration of SK-MEL-28 cells stimulated by 12-O-tetradecanoylphorbol-13-acetate (TPA) was attenuated by adding DPG by wound-healing assay (48 h: p-value = 0.004; 72 h: p-value = 7.0 × 10−4). In addition, the MMP-9 expression level was inhibited by DPG in melanoma cells stimulated by TPA and compared to TPA-treated cells (3.56 vs. 0.99 AUs, p-value = 0.0016) after 24 h of treatment. Our results suggested that DPG has an apoptotic, anti-proliferative, and anti-migratory effect on SK-MEL-28 cells. DPG was also able to inhibit cancer stem-like cells that may cause cerebral tumor formation.

Laminaria japonica fucoidan ameliorates cyclophosphamide-induced liver and kidney injury possibly by regulating Nrf2/HO-1 and TLR4/NF-κB signaling pathways.

BACKGROUND: During clinical practice, cyclophosphamide (CTX) can lead to liver and kidney injury in vivo. In this study, we established a liver and kidney injury model by injecting CTX (80 mg kg-1 d-1 ) into male ICR mice, and then mice were treated with saline and fucoidan (20 or 40 mg kg-1 ), respectively. Subsequently, the liver and kidney toxicity indices, the expression levels of malonic dialdehyde (MDA), inflammatory factors, and the main protein levels of the Nrf2/HO-1 and TLR4/NF-κB pathways were determined. RESULTS: Our results indicated that fucoidan could significantly decrease serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine (CRE), and urea (BUN) in the test group compared to the model group. Fucoidan administration caused reductions in MDA, interleukin-6 (IL-6), IL-1ß, and tumor necrosis factor alpha (TNF-α) levels and improved superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in the liver and kidney of CTX-induced mice. Fucoidan up-regulated the Nrf2/HO-1 pathway and enhanced the protein levels of Nrf2, HO-1, GCLM, and NQO1. Moreover, fucoidan down-regulated the TLR4/NF-κB pathway, as indicated by decreased levels of TLR4, NF-κB p65, NF-κB p50, and increased IκBα level in liver and kidney tissues. CONCLUSION: Our studies suggest that fucoidan can ameliorate CTX-induced liver and kidney injury, potentially via up-regulating the Nrf2/HO-1 pathway and inhibiting the TLR4/NF-κB pathway. © 2021 Society of Chemical Industry.

Disclosing the potential of eleganolone for Parkinson's disease therapeutics: Neuroprotective and anti-inflammatory activities.

The treatment of Parkinson´s disease (PD) has benefited from significant advances resulting from the increasing research efforts focused on new therapeutics. However, the current treatments for PD are mostly symptomatic, alleviating disease symptoms without reversing or retarding disease progression. Thus, it is critical to find new molecules that can result in more effective treatments. Within this framework, this study aims to evaluate the neuroprotective and anti-inflammatory effects of three compounds (eleganolone, eleganonal and fucosterol) isolated from the brown seaweed Bifurcaria bifurcata. In vitro neuroprotective effects were evaluated on a PD cellular model induced by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y human cells, while lipopolysaccharide (LPS) - stimulated RAW 264.7 macrophages were used to evaluate the anti-inflammatory potential. Additionally, the underlying mechanisms of action were also investigated. Compounds were isolated by preparative chromatographic methods and their structural elucidation attained by NMR spectroscopy. Among the tested compounds, eleganolone (0.1-1 µM; 24 h) reverted the neurotoxicity induced by 6-OHDA in about 20%. The neuroprotective effects were mediated by mitochondrial protection, reduction of oxidative stress, inflammation and apoptosis, and inhibition of NF-kB pathway. The results suggest that eleganolone may provide advantages in the treatment of neurodegenerative conditions and, therefore, should be considered for future preclinical studies.

Yishen capsule promotes podocyte autophagy through regulating SIRT1/NF-κB signaling pathway to improve diabetic nephropathy.

Diabetic nephropathy (DN) is a common complication of diabetes. Yishen capsule, composed of Chinese herbs, improves the clinical outcome in DN patients. However, its therapeutic potential and underlying mechanisms require further elucidation. Hence, our study aimed to investigate the underlying mechanisms and therapeutic potential of Yishen capsule in DN. Streptozotocin-induced DN rats were treated with Yishen capsules (1.25 g/kg/day) for 8 weeks. Then, blood glucose and urine protein levels were measured. Hematoxylin and eosin staining and western blot assays were used to examine the histologic changes and gene expression, respectively, in kidney samples. Mouse podocytes were treated with rat serum containing Yishen capsule and transmission electron microscopy was used to examine autophagosome formation. Cell counting kit-8 assay was performed to examine cell proliferation. Western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analyses were conducted to detect changes in gene expression. The localization of SIRT1 was examined in the podocytes using immunocytofluorescence assay. We found that Yishen capsule relieved pathological changes, decreased urine protein, increased SIRT1, LC3-II, and Beclin-1 expression, and reduced acetylated NF-κB p65 expression in vivo. In addition, rat serum containing Yishen capsule showed improved podocyte proliferation, promoted the mRNA and protein levels of LC3-II and Beclin-1, and induced nuclear translocation of SIRT1. Furthermore, it increased SIRT1 expression and decreased mRNA level of NF-κB in the serum. SIRT1 inhibitor increased the mRNA level of NF-κB. Our data suggests that Yishen capsule improves DN by promoting podocyte autophagy via the SIRT1/NF-κB pathway.

Loliolide, a New Therapeutic Option for Neurological Diseases? In Vitro Neuroprotective and Anti-Inflammatory Activities of a Monoterpenoid Lactone Isolated from Codium tomentosum.

Parkinsons Disease (PD) is the second most common neurodegenerative disease worldwide, and is characterized by a progressive degeneration of dopaminergic neurons. Without an effective treatment, it is crucial to find new therapeutic options to fight the neurodegenerative process, which may arise from marine resources. Accordingly, the goal of the present work was to evaluate the ability of the monoterpenoid lactone Loliolide, isolated from the green seaweed Codium tomentosum, to prevent neurological cell death mediated by the neurotoxin 6-hydroxydopamine (6-OHDA) on SH-SY5Y cells and their anti-inflammatory effects in RAW 264.7 macrophages. Loliolide was obtained from the diethyl ether extract, purified through column chromatography and identified by NMR spectroscopy. The neuroprotective effects were evaluated by the MTT method. Cells' exposure to 6-OHDA in the presence of Loliolide led to an increase of cells' viability in 40%, and this effect was mediated by mitochondrial protection, reduction of oxidative stress condition and apoptosis, and inhibition of the NF-kB pathway. Additionally, Loliolide also suppressed nitric oxide production and inhibited the production of TNF-α and IL-6 pro-inflammatory cytokines. The results suggest that Loliolide can inspire the development of new neuroprotective therapeutic agents and thus, more detailed studies should be considered to validate its pharmacological potential.

MiR-590-3p regulates cardiomyocyte P19CL6 proliferation, apoptosis and differentiation in vitro by targeting PTPN1 via JNK/STAT/NF-kB pathway.

Cardiomyocyte differentiation is a multi-step process which involves a number of signalling pathways. microRNAs exhibit regulatory functions in various diseases and are involved in the signalling pathways in multiple physiological processes, but the specific functions of particular mRNAs is often not fully understood. of an example of this is that the role of miR-590-3p in the differentiation of cardiomyocytes remains unclear. In the current study, RT-qPCR was used to determine the expression of miR-590-3p in cardiomyocytes differentiated from the embryonic carcinoma cell line P19CL6. MTT, EdU, caspase-3 activity and flow cytometry assays were performed to examine the influence of miR-590-3p on cell behaviour. A luciferase assay was used to confirm binding between miR-590-3p and PTPN1. Western blotting was used to determine the relationship between the JNK/STAT/NF-kB pathway and PTPN1. The results inferred that miR-590-3p became heavily expressed in differentiated P19CL6. Knockdown miR-590-3p suppressed the cell proliferation while at the same time, accelerated apoptosis. Moreover, PTPN1 was identified as the target of miR-590-3p. More importantly, PTPN1 overexpression activated the JNK/STAT/NF-kB pathway and limited the differentiation of P19CL6. Thus the conclusions from this study are that miR-590-3p has the potential to regulate the proliferation, apoptosis and differentiation of cardiomyocyte P19CL6 in vitro by targeting PTPN1 via the JNK/STAT/NF-kB pathway.

Temporal changes of NF-κB signaling pathway genes in bacterial stimulated whole blood- a host mechanism associated with sepsis.

Bacterial sepsis affects both neonates and adults worldwide. There is no specific anti-sepsis treatment. Disease management mainly depends on early diagnosis. The gold standard blood culturing method is routinely practiced; it requires 24-48 h for confirmation. Understanding the disease mechanism may help in the early detection of sepsis. We studied the temporal change in NF-kB pathway genes in adult whole blood upon bacterial stimulations across time intervals (2-6 h). Four experimental conditions were investigated (1: Gram-positive, 2: Gram-negative, 3: Gram-positive + Gram-negative stimulated and compared with 4: un-stimulated group) to show host selection of canonical or non-canonical pathway against invading pathogens. Gene expression analysis showed significant variations (p < 0.5) in TLR2, TLR4, TRAF6, NIK, RelA, and RelB upon bacterial stimulants. Further, the correlation analysis showed the coherent behaviour of genes in selecting the canonical or non-canonical pathway. TLR2 sensed by gram-positive bacteria that immediately activates the canonical pathway through RelA, whereas other bacterial stimulants activate the non-canonical pathway via TLR4, NIK, and RelB. In addition, the inflammatory markers showed a significant increase in response to bacterial stimulants, suggesting the immediate activation of innate immunity. Overall, our results show the bacterial specific and time-dependent activation of the NF-kB pathway, which through a light towards the early detection of bacterial sepsis.

Glycyrrhizin ameliorates inflammatory pain by inhibiting microglial activation-mediated inflammatory response via blockage of the HMGB1-TLR4-NF-kB pathway.

Chronic inflammatory pain is a severe clinical problem that greatly affects patients' quality of life and causes huge economic burden. Microglia-mediated neuroinflammation exerts critical roles in the pathogenic progression of inflammatory pain. Recent evidence corroborates the anti-inflammatory and neuroprotective efficacy of glycyrrhizin; however, its function in inflammatory pain remains poorly elucidated. In the present study, glycyrrhizin suppressed LPS-induced activation of microglial cell BV2 by inhibiting NO production and expression of microglial marker IBA-1. Intriguingly, LPS-induced high expression and generation of inflammatory cytokines (i.e., IL-6, TNF-α and IL-1ß) was notably reversed by glycyrrhizin pre-treatment. Mechanistic analysis confirmed that high expression of high-mobility group box 1 (HMGB1) in LPS-activated microglia was inhibited following glycyrrhizin. More importantly, restoring HMGB1 expression by recombinant adenovirus vector of Ad-HMGB1 counteracted glycyrrhizin-restrained inflammatory response in microglia upon LPS stimulation. Furthermore, glycyrrhizin dampened the activation of subsequent TLR4-NF-κB pathway in LPS-stimulated microglia, which was abrogated by HMGB1 elevation. Furthermore, blocking this pathway by si-TLR4 transfection reversed the effects of HMGB1 overexpression on the inhibitor roles of glycyrrhizin in microglia-triggered inflammation. Additionally, glycyrrhizin administration also alleviated CFA-evoked mechanical allodynia and thermal hyperalgesia in inflammatory pain model of mice, concomitant with suppression in inflammatory response and microglial activation. Simultaneously, elevation of HMGB1, TLR4 and p65-NF-κB protein expression induced by CFA injection was also abrogated after glycyrrhizin. Accordingly, this study reveal that glycyrrhizin may act as a promising therapeutic avenue for the treatment of inflammatory pain.

Phytochemical, in-vitro biological and chemo-preventive profiling of Arisaema jacquemontii Blume tuber extracts.

BACKGROUND: Arisaema jacquemontii is traditionally used in treatment of different diseases. In this study, phytochemical, in vitro biological and chemo-preventive screening of A. jacquemontii was carried out to explore its pharmacological potential. METHODS: The dried tuber of A. jacquemontii was extracted in 11 organic solvent mixture of different polarity. The extracts were screened for phytochemical assays (phenolics and flavonoids), antioxidants potential (free radical scavenging activity, total antioxidant activity, reducing power), biological activities (antibacterial, antifungal, cytotoxic, antileishmanial, protein kinase inhibition), and chemopreventive activities using different cell lines through standard protocols. RESULTS: Significant amount phenolic contents were determined in EtOH and MeOH extracts (210.3 ± 3.05 and 193.2 ± 3.15 µg GAE/mg, respectively). Maximum flavonoid content was determined in MeOH extract (22.4 ± 4.04 µg QE/mg). Noteworthy, DPPH scavenging activity was also recorded for MeOH extract (87.66%) followed by MeOH+EtOAc extract (85.11%). Considerable antioxidant capacity (7.8 ± 0.12 µg AAE/mg) and reducing power (3.1 ± 0.15 µg AAE/mg) was observed in extract of MeOH. The LC50 against brine shrimp and leishmanial parasite was found 9.01 and 12.87 µg/mL for n-Hex and CHCl3 extracts, respectively. The highest zone of inhibition against Streptomyces hyphae formation (12.5 ± 1.77 mm) by n-Hex extract. Growth zone of inhibition 13.8 ± 1.08 mm was recorded for EtOAc and MeOH extracts, respectively against Micrococcus luteus while 10.0 ± 0.11 mm for MeOH extract against Aspergillus flavus. In-vitro cytotoxic assay showed that n-Hex extract had higher cytotoxicity against DU-145 prostate cancer and HL-60 cancer cell lines. NF-kB and MTP potential showed 34.01 and 44.87 µg/mL for n-Hex and CHCl3 extracts, respectively in chemo-preventive potential. CONCLUSION: The study concludes that Arisaema jacquemontii bears significant phytochemical activity and pharmacological activities, this plant can be further explored for isolation of active component against a number of aliments.

miRNA-20a upregulates TAK1 and increases proliferation in osteosarcoma cells.

AIM: The aim of this study is to explore the function of miR-20a in osteosarcoma. MATERIALS & METHODS: miR-20a expression was measured by real-time PCR. miR-20a mimics, inhibitor and scramble siRNA were transfected into osteosarcoma cells to observe effects on colony formation and tumor growth. Moreover, relationships of miR-20a with TAK1 were investigated by western blot and luciferase activity. RESULTS: We found that miR-20a was downregulated in osteosarcoma, and overexpression of miR-20a reduced colony formation and tumor growth. Furthermore, the data revealed that the function of miR-20a was probably exerted via targeting the TAK1 expression. Overexpression of miR-20a sensitizes the osteosarcoma cells to chemotherapeutic drugs. CONCLUSION: Our data identify the role of miR-20a in osteosarcoma growth, indicating its potential application in chemotherapy.

High IKKα expression is associated with reduced time to recurrence and cancer specific survival in oestrogen receptor (ER)-positive breast cancer.

The aim of our study was to examine the relationship between tumour IKKα expression and breast cancer recurrence and survival. Immunohistochemistry was employed in a discovery and a validation tissue microarray to assess the association of tumour IKKα expression and clinico-pathological characteristics. After siRNA-mediated silencing of IKKα, cell viability and apoptosis were assessed in MCF7 and MDA-MB-231 breast cancer cells. In both the discovery and validation cohorts, associations observed between IKKα and clinical outcome measures were potentiated in oestrogen receptor (ER) positive Luminal A tumours. In the discovery cohort, cytoplasmic IKKα was associated with disease-free survival (p = 0.029) and recurrence-free survival on tamoxifen (p < 0.001) in Luminal A tumours. Nuclear IKKα and a combination of cytoplasmic and nuclear IKKα (total tumour cell IKKα) were associated with cancer-specific survival (p = 0.012 and p = 0.007, respectively) and recurrence-free survival on tamoxifen (p = 0.013 and p < 0.001, respectively) in Luminal A tumours. In the validation cohort, cytoplasmic IKKα was associated with cancer-specific survival (p = 0.023), disease-free survival (p = 0.002) and recurrence-free survival on tamoxifen (p = 0.009) in Luminal A tumours. Parallel experiment with breast cancer cells in vitro demonstrated the non-canonical NF-κB pathway was inducible by exposure to lymphotoxin in ER-positive MCF7 cells and not in ER-negative MDA-MB-231 cells. Reduction in IKKα expression by siRNA transfection increased levels of apoptosis and reduced cell viability in MCF7 but not in MDA-MB-231 cells. IKKα is an important determinant of poor outcome in patients with ER-positive invasive ductal breast cancer and thus may represent a potential therapeutic target.

p62/SQSTM1 as an oncotarget mediates cisplatin resistance through activating RIP1-NF-κB pathway in human ovarian cancer cells.

Platinum-based therapeutic strategies have been widely used in ovarian cancer treatment. However, drug resistance has greatly limited therapeutic efficacy. Recently, tolerance to cisplatin has been attributed to other factors unrelated to DNA. p62 (also known as SQSTM1) functions as a multifunctional hub participating in tumorigenesis and may be a therapeutic target. Our previous study showed that p62 was overexpressed in drug-resistant ovarian epithelial carcinoma and its inhibition increased the sensitivity to cisplatin. In this study, we demonstrate that the activity of the NF-κB signaling pathway and K63-linked ubiquitination of RIP1 was higher in cisplatin-resistant ovarian (SKOV3/DDP) cells compared with parental cells. In addition, cisplatin resistance could be reversed by inhibiting the expression of p62 using siRNA. Furthermore, deletion of the ZZ domain of p62 that interacts with RIP1 in SKOV3 cells markedly decreased K63-linked ubiquitination of RIP1 and inhibited the activation of the NF-κB signaling pathway. Moreover, loss of the ZZ domain from p62 led to poor proliferative capacity and high levels of apoptosis in SKOV3 cells and made them more sensitive to cisplatin treatment. Collectively, we provide evidence that p62 is implicated in the activation of NF-κB signaling that is partly dependent on RIP1. p62 promotes cell proliferation and inhibits apoptosis thus mediating drug resistance in ovarian cancer cells.

An intracellular adrenomedullin system reduces IL-6 release via a NF-kB-mediated, cAMP-independent transcriptional mechanism in rat thymic epithelial cells.

Thymic epithelial cells (TECs) play a key role in the regulation of central immune tolerance by expressing autoantigens and eliminating self-reactive T cells. In a previous paper we reported that adrenomedullin (ADM) and its co-receptor protein RAMP2 are located intracellularly in newborn human thymic epithelial cells (TECs). This work has two main aims: (1) to examine the cellular localization of ADM and its receptor in TECs of adult Wistar rats to validate this animal model for the study of the ADM system and its function(s) in thymus; (2) to investigate the potential modulating effect of ADM on the NF-kB pathway, which is involved through the production of cytokines such as IL-6, in the maturation of T-lymphocytes and immunological tolerance. Our results show that, similarly to human newborn TECs, ADM is localized to the cytoplasm of adult rat TECs, and RAMP2 is expressed in the nucleus but not in the plasma membrane. Pretreatment of TECs for 4h with ADM significantly reduced lipopolysaccharide (LPS)-induced release of IL-6 (P<0.001) and expression of the p65 subunit of NF-kB, while doubled the expression of IkBα (P<0.001), the physiological inhibitor of NF-kB nuclear translocation. These effects were not mediated by activation of the cAMP pathway, a signalling cascade that is rapidly activated by ADM in cells that express plasma membrane RAMP2, but were the consequence of a reduction in the transcription of p65 (P<0.001) and an increase in the transcription of IkBα (P<0.05). On the basis of these findings we propose that in rat TECs ADM reduces IL-6 secretion by modulating NF-kB genes transcription through an interaction with a receptor localized to the nucleus. This may partly explain the protective effects of ADM in autoimmune diseases and points to the ADM system of TECs as a novel potential target for immunomodulating drugs.

The effect of melatonin on oxidative stress and apoptosis in experimental diabetes mellitus-related ovarian injury.

We aimed to evaluate the effect of melatonin on oxidative stress and ovarian injury in rats. Twenty-four Sprague-Dawley albino rats were divided into three groups: Group 1 as nondiabetic healthy controls (n = 8), group 2 as nontreated diabetic rats (n = 8) and group 3 as melatonin-treated diabetic rats (n = 8). After overt diabetes was produced by intraperitoneal injection of streptozosin, 20 mg/kg/day of melatonin was given intraperitoneally to group 3 for a week. NF-kB and caspase-3 immunoexpressions, lipid peroxidation, the activities of antioxidative enzymes, total oxidant capacity and total antioxidant capacity were assessed. Immunoexpressions of NF-kB and caspase-3 were significantly lower in group 3 than group 2. There was a significant decrease in superoxide dismutase activity in group 2 than group 1 and a significant increase in group 3 compared with group 2. We observed a nonsignificant decrease in catalase activity between group 1 and group 2 and a nonsignificant increase between group 2 and group 3. There was a nonsignificant increase in the plasma level of total oxidant status in group 2 than group 1, but a significant decrease was observed in group 3 compared to group 2. Total antioxidant status was significantly lower in group 2 compared with group 1 and group 3. In conclusion, melatonin ameliorates the negative effects of oxidative stress on DM-related ovarian injury.

Insight into IKBKG/NEMO locus: report of new mutations and complex genomic rearrangements leading to incontinentia pigmenti disease.

Incontinentia pigmenti (IP) is an X-linked-dominant Mendelian disorder caused by mutation in the IKBKG/NEMO gene, encoding for NEMO/IKKgamma, a regulatory protein of nuclear factor kappaB (NF-kB) signaling. In more than 80% of cases, IP is due to recurrent or nonrecurrent deletions causing loss-of-function (LoF) of NEMO/IKKgamma. We review how the local architecture of the IKBKG/NEMO locus with segmental duplication and a high frequency of repetitive elements favor de novo aberrant recombination through different mechanisms producing genomic microdeletion. We report here a new microindel (c.436_471delinsT, p.Val146X) arising through a DNA-replication-repair fork-stalling-and-template-switching and microhomology-mediated-end-joining mechanism in a sporadic IP case. The LoF mutations of IKBKG/NEMO leading to IP include small insertions/deletions (indel) causing frameshift and premature stop codons, which account for 10% of cases. We here present 21 point mutations previously unreported, which further extend the spectrum of pathologic variants: 14/21 predict LoF because of premature stop codon (6/14) or frameshift (8/14), whereas 7/21 predict a partial loss of NEMO/IKKgamma activity (two splicing and five missense). We review how the analysis of IP-associated IKBKG/NEMO hypomorphic mutants has contributed to the understanding of the pathophysiological mechanism of IP disease and has provided important information on affected NF-kB signaling. We built a locus-specific database listing all IKBKG/NEMO variants, accessible at http://IKBKG.lovd.nl.

Alpha T-catenin: a crucial tumor suppressor in cancer pathogenesis.

Alpha T-catenin has recently been identified as a crucial tumor suppressor in various cancer types, with roles that go beyond just providing structural support in adherens junctions. This review brings together recent findings on alpha T-catenin's important involvement in key signaling pathways related to cancer progression. We present strong evidence of its regulatory role in Wnt signaling, a pathway often disrupted in colorectal cancer, and explain how it inhibits cell proliferation and tumor growth. We also discuss the significant downregulation of alpha T-catenin in colorectal cancers and its potential as a prognostic marker. Moreover, this review looks at how increasing alpha T-catenin levels can reduce tumor growth and spread, suggesting new therapeutic strategies. Additionally, we reveal alpha T-catenin's unexpected impact on NF-κB signaling in basal E-cadherin-negative breast cancer, expanding its importance across different cancer types. By bringing these findings together, we provide a thorough understanding of alpha T-catenin's tumor-suppressing actions, setting the stage for new targeted therapies and diagnostic tools in cancer treatment.