Augmentation of NAD+ by Dunnione Ameliorates Imiquimod-Induced Psoriasis-Like Dermatitis in Mice

Background

Dunnione has anti-inflammatory properties arising from its ability to alter the ratio of NAD⁺/NADH through NAD(P)H quinone oxidoreductase 1 (NQO1) enzymatic action, followed by subsequent inhibition of NF-κB and inflammatory cytokines. Psoriasis is a chronic, inflammatory skin disorder in which the IL-23/Th17 axis plays an important role in inflammation. However, it is unclear whether modulation of NAD⁺ levels affects psoriasis, such as skin inflammation. Therefore, in this study, we investigated the effect of NAD⁺/NADH ratio modulation on imiquimod (IMQ)-induced, psoriasis-like skin inflammation in mice.

Methods

Psoriasis-like skin inflammation was generated by daily topical application of IMQ cream. The severity of dermatitis was assessed using the Psoriasis Area Severity Index (PASI) and histochemistry. Expression of inflammatory cytokines was detected by enzyme-linked immunosorbent assay and quantitative PCR. Acetylation of NF-κB p65 and STAT3 was determined by Western blotting.

Results

Dunnione improved IMQ-induced epidermal hyperplasia and inflammation, consistent with decreased levels of inflammatory cytokines (IL-17, IL-22, and IL-23) in skin lesions. Moreover, we found that an increase in the NAD⁺/NADH ratio by dunnione restored SIRT1 activity, thereby reduced imiquimod-induced STAT3 acetylation, which modulates the expression of psoriasis-promoting inflammatory cytokines, such as IL-17, IL-22, and IL-23.

Conclusion

Pharmacological modulation of cellular NAD⁺ levels could be a promising therapeutic approach for psoriasis-like skin disease.

Modulation of Cellular NAD+ Attenuates Cancer-Associated Hypercoagulability and Thrombosis via the Inhibition of Tissue Factor and Formation of Neutrophil Extracellular Traps

Cancer-associated thrombosis is the second-leading cause of mortality in patients with cancer and presents a poor prognosis, with a lack of effective treatment strategies. NAD(P)H quinone oxidoreductase 1 (NQO1) increases the cellular nicotinamide adenine dinucleotide (NAD⁺) levels by accelerating the oxidation of NADH to NAD⁺, thus playing important roles in cellular homeostasis, energy metabolism, and inflammatory responses. Using a murine orthotopic 4T1 breast cancer model, in which multiple thrombi are generated in the lungs at the late stage of cancer development, we investigated the effects of regulating the cellular NAD⁺ levels on cancer-associated thrombosis. In this study, we show that dunnione (a strong substrate of NQO1) attenuates the prothrombotic state and lung thrombosis in tumor-bearing mice by inhibiting the expression of tissue factor and formation of neutrophil extracellular traps (NETs). Dunnione increases the cellular NAD⁺ levels in lung tissues of tumor-bearing mice to restore the declining sirtuin 1 (SIRT1) activity, thus deacetylating nuclear factor-kappa B (NF-κB) and preventing the overexpression of tissue factor in bronchial epithelial and vascular endothelial cells. In addition, we demonstrated that dunnione abolishes the ability of neutrophils to generate NETs by suppressing histone acetylation and NADPH oxidase (NOX) activity. Overall, our results reveal that the regulation of cellular NAD⁺ levels by pharmacological agents may inhibit pulmonary embolism in tumor-bearing mice, which may potentially be used as a viable therapeutic approach for the treatment of cancer-associated thrombosis.

Emergency attendances and hospitalisations for complications after transrectal ultrasound-guided prostate biopsies: a five-year retrospective multicentre study

INTRODUCTION

Transrectal ultrasound-guided (TRUS) prostate biopsy is an established procedure for diagnosis of prostate cancer. Complications after TRUS biopsy are not well reported in Hong Kong. This study evaluated the 5-year incidences of TRUS biopsy complications and potential risk factors for those complications.

METHODS

This was a retrospective review of biopsies performed from 2013 to 2017 in two local hospitals, using data retrieved from electronic medical records. The primary outcome was the occurrence of complications requiring either emergency attendances or hospitalisations within 30 days after biopsy. Potential risk factors were examined using multiple logistic regression analysis.

RESULTS

In total, 1699 men were included (mean age ± standard deviation: 67 ± 7 years; median prostate-specific antigen level: 7.9 μg/L [interquartile range, 5.5-12.6 μg/L]); 4.3% had pre-biopsy bacteriuria. Overall, 5.7% and 3.8% of post-biopsy complications required emergency attendances and hospitalisations, respectively. Gross haematuria and rectal bleeding requiring emergency attendances developed in 2.1% and 0.4% of men; 0.8% and 0.4% required hospitalisations. Furthermore, 1.5% of men developed acute urinary retention requiring hospitalisations; 1.9% and 1.2% had post-biopsy infections requiring emergency attendances and hospitalisations, respectively, and 0.9% had urosepsis requiring hospitalisations. Prostate volume >48 cc was associated with an increased risk of post-biopsy retention (odds ratio 2.75, 95% confidence interval: 1.23-4.17).

CONCLUSIONS

The rate of overall complications after TRUS biopsy was low. The most common complications requiring emergency attendances and hospitalisations were gross haematuria and acute urinary retention, respectively. Prostate volume >48 cc increased the risk of post-biopsy urinary retention.

Abstract 2717: Role of NAD+ level by NQO1 enzymatic action in regulation of hair regrowth that prevents chemotherapy-induced alopecia

Various types of chemotherapeutic agents are widely used to treat a variety of human neoplasms. Nonetheless, its clinical use is hampered because of severe adverse side effects such as alopecia, neutropenia, pain, cachexia, conception impairment etc. Chemotherapy-induced alopecia (CIA) is one of the fundamental unsolved problems of clinical oncology that often encountered in cancer treatment. CIA has been reported to be caused by skin inflammation through oxidative stress, DNA damage, and inflammatory responses. However, the best remedy for CIA is still not established. In a new strategy, we show that WK0202 compound as a strong NQO1 substrate that modulates the intracellular NAD+ levels by NAD(P)H quinone oxidoreductase 1 (NQO1) enzymatic action and plays important role in hair regrowth response to single (cyclophosphamide-CYP) or combined (taxol, adriamycin and cyclophosphamide-TAC) cancer therapy. Particularly, we demonstrated that cellular NAD+ levels as well as SIRT1 activity and its expression was decreased in skin with hair follicles after CYP and TAC treatment, and PARP-1 hyperactivation was associated with CIA through increased nuclear factor (NF)-κB p65 and p53 acetylation in wild type, NQO1-/- and K14-/- C57BL/6 mice. However, an increase in NAD+ levels by WK0202 completely restored SIRT1 activity and its expression, and subsequently deacetylated NF-κB p65 and p53 in wild type, however not in NQO1-/- and K14-/- mice thereby attenuating CIA. Therefore, modulation of NAD+ levels by NQO1 may be a novel therapeutic approach to prevent chemotherapy-associated hair loss, including CIA.

Citation Format: Dipendra Khadka, Gi-Su Oh, Hyung-Jin Kim, SeungHoon Lee, Su-bin Lee, Subham Sharma, Seon Young Kim, Tae Hwan Kwak, Sei-Hoon Yang, Hyuk Sim, Hong-Seob So. Role of NAD+ level by NQO1 enzymatic action in regulation of hair regrowth that prevents chemotherapy-induced alopecia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2717.

Slc25a17 acts as a peroxisomal coenzyme A transporter and regulates multiorgan development in zebrafish

Slc25a17 is known as a peroxisomal solute carrier, but the in vivo role of the protein has not been demonstrated. We found that the zebrafish genome contains two slc25a17 genes that function redundantly, but additively. Notably, peroxisome function in slc25a17 knockdown embryos is severely compromised, resulting in an altered lipid composition. Along the defects found in peroxisome-associated phenotypic presentations, we highlighted that development of the swim bladder is also highly dependent on Slc25a17 function. As Slc25a17 showed substrate specificity towards coenzyme A (CoA), injecting CoA, but not NAD⁺ , rescued the defective swim bladder induced by slc25a17 knockdown. These results indicated that Slc25a17 acts as a CoA transporter, involved in the maintenance of functional peroxisomes that are essential for the development of multiple organs during zebrafish embryogenesis. Given high homology in protein sequences, the role of zebrafish Slc25a17 may also be applicable to the mammalian system.

Augmentation of NAD+ levels by enzymatic action of NAD(P)H quinone oxidoreductase 1 attenuates adriamycin-induced cardiac dysfunction in mice

BACKGROUND

Adriamycin (ADR) is a powerful chemotherapeutic agent extensively used to treat various human neoplasms. However, its clinical utility is hampered due to severe adverse side effects i.e. cardiotoxicity and heart failure. ADR-induced cardiomyopathy (AIC) has been reported to be caused by myocardial damage and dysfunction through oxidative stress, DNA damage, and inflammatory responses. Nonetheless, the remedies for AIC are even not established. Therefore, we illustrate the role of NAD⁺/NADH modulation by NAD(P)H quinone oxidoreductase 1 (NQO1) enzymatic action on AIC.

METHODS AND RESULTS

AIC was established by intraperitoneal injection of ADR in C57BL/6 wild-type (WT) and NQO1 knockout (NQO1^-/-) mice. All Mice were orally administered dunnione (named NQO1 substrate) before and after exposure to ADR. Cardiac biomarker levels in the plasma, cardiac dysfunction, oxidative biomarkers, and mRNA and protein levels of pro-inflammatory mediators were determined compared the cardiac toxicity of each experimental group. All biomarkers of Cardiac damage and oxidative stress, and mRNA levels of pro-inflammatory cytokines including cardiac dysfunction were increased in ADR-treated both WT and NQO1^-/- mice. However, this increase was significantly reduced by dunnione in WT, but not in NQO1^-/- mice. In addition, a decrease in SIRT1 activity due to a reduction in the NAD⁺/NADH ratio by PARP-1 hyperactivation was associated with AIC through increased nuclear factor (NF)-κB p65 and p53 acetylation in both WT and NQO1^-/- mice. While an elevation in NAD⁺/NADH ratio via NQO1 enzymatic action using dunnione recovered SIRT1 activity and subsequently deacetylated NF-κB p65 and p53, however not in NQO1^-/- mice, thereby attenuating AIC.

CONCLUSION

Thus, modulation of NAD⁺/NADH by NQO1 may be a novel therapeutic approach to prevent chemotherapy-associated heart failure, including AIC.

PEX5 regulates autophagy via the mTORC1-TFEB axis during starvation

Defects in the PEX5 gene impair the import of peroxisomal matrix proteins, leading to nonfunctional peroxisomes and other associated pathological defects such as Zellweger syndrome. Although PEX5 regulates autophagy process in a stress condition, the mechanisms controlling autophagy by PEX5 under nutrient deprivation are largely unknown. Herein, we show a novel function of PEX5 in the regulation of autophagy via Transcription Factor EB (TFEB). Under serum-starved conditions, when PEX5 is depleted, the mammalian target of rapamycin (mTORC1) inhibitor TSC2 is downregulated, which results in increased phosphorylation of the mTORC1 substrates, including 70S6K, S6K, and 4E-BP-1. mTORC1 activation further suppresses the nuclear localization of TFEB, as indicated by decreased mRNA levels of TFEB, LIPA, and LAMP1. Interestingly, peroxisomal mRNA and protein levels are also reduced by TFEB inactivation, indicating that TFEB might control peroxisome biogenesis at a transcriptional level. Conversely, pharmacological inhibition of mTOR resulting from PEX5 depletion during nutrient starvation activates TFEB by promoting nuclear localization of the protein. In addition, mTORC1 inhibition recovers the damaged-peroxisome biogenesis. These data suggest that PEX5 may be a critical regulator of lysosomal gene expression and autophagy through the mTOR-TFEB-autophagy axis under nutrient deprivation.

A protein essential for the formation of peroxisomes—cellular organelles that perform diverse metabolic functions—also regulates cellular ‘recycling centers’ that break biomolecules down into nutrients. Researchers led by Raekil Park at the Gwangju Institute of Science and Technology in South Korea have now linked this protein, known as PEX5, to the function of another critical cellular organelle. Lysosomes participate in a process called autophagy, in which non-essential or damaged cellular components and biomolecules are digested to generate nutrients in times of deprivation. Park’s team determined that in the absence of PEX5, starved cells lose the ability to effectively initiate autophagy. They also identified the molecular pathways affected by PEX5 deficiency. These findings indicate a strong functional link between the peroxisome and lysosome, and could aid the development of treatments for certain metabolic disorders.

Expression Profile of Three Splicing Factors in Pleural Cells Based on the Underlying Etiology and Its Clinical Values in Patients with Pleural Effusion

Splicing factors (SFs) are involved in oncogenesis or immune modulation, the common underlying processes giving rise to pleural effusion (PE). The expression profiles of three SFs (HNRNPA1, SRSF1, and SRSF3) and their clinical values have never been assessed in PE. The three SFs (in pellets of PE) and conventional tumor markers were analyzed using PE samples in patients with PE (N = 336). The sum of higher-molecular weight (Mw) forms of HNRNPA1 (Sum-HMws-HNRNPA1) and SRSF1 (Sum-HMws-SRSF1) and SRSF3 levels were upregulated in malignant PE (MPE) compared to benign PE (BPE); they were highest in cytology-positive MPE, followed by tuberculous PE and parapneumonic PE. Meanwhile, the lowest-Mw HNRNPA1 (LMw-HNRNPA1) and SRSF1 (LMw-SRSF1) levels were not upregulated in MPE. Sum-HMws-HNRNPA1, Sum-HMws-SRSF1, and SRSF3, but neither LMw-HNRNPA1 nor LMw-SRSF1, showed positive correlations with cancer cell percentages in MPE. The detection accuracy for MPE was high in the order of carcinoembryonic antigen (CEA, 85%), Sum-HMws-HNRNPA1 (76%), Sum-HMws-SRSF1 (68%), SRSF3, cytokeratin-19 fragments (CYFRA 21-1), LMw-HNRNPA1, and LMw-SRSF1. Sum-HMws-HNRNPA1 detected more than half of the MPE cases that were undetected by cytology and CEA. Sum-HMws-HNRNPA1, but not other SFs or conventional tumor markers, showed an association with longer overall survival among patients with MPE receiving chemotherapy. Our results demonstrated different levels of the three SFs with their Mw-specific profiles depending on the etiology of PE. We suggest that Sum-HMws-HNRNPA1 is a supplementary diagnostic marker for MPE and a favorable prognostic indicator for patients with MPE receiving chemotherapy.

Effects of Banxia Xiexin Decoction () on Cisplatin-Induced Apoptosis of Human A549 Lung Cancer Cells

OBJECTIVE

To examinie the synergistic effects of Banxia Xiexin Decoction (, Known as Banhasasim-tang in Korean) extract (BXDE) on cisplatin-induced cytotoxicity in the A549 human lung cancer cell lines.

METHODS

A549 cells were treated with varying concentrations (50-200 μg/mL) of cisplatin and BXDE alone or in combination for 96 h. We used 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan assay and flow cytometry to analyze cell viability and apoptosis, respectively.

RESULTS

The exposure of cells to cisplatin and BXDE alone or in combination decreased cell viability dose- and time-dependently (P<0.05), which was found to be mediated by the apoptotic pathway as confirmed by the increase in the annexin V⁺/propidium iodide- stained cell population and a ladder pattern of discontinuous DNA fragments. Furthermore, the apoptosis was inhibited by the pan-caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (OMe) fluoromethylketone (z-VAD-FMK).

CONCLUSIONS

BXDE significantly potentiated apoptotic effects of cisplatin in A549 cells. Moreover, apoptosis induced by BXDE might be the pivotal mechanism mediating its chemopreventative action against cancer.

Albiflorin ameliorates obesity by inducing thermogenic genes via AMPK and PI3K/AKT in vivo and in vitro

OBJECTIVE

Brown adipose tissue (BAT) activation has been identified as a possible target to treat obesity and to protect against metabolic diseases by increasing energy consumption. We explored whether albiflorin (AF), a natural compound, could contribute to lowering the high risk of obesity with BAT and primary brown preadipocytes in vivo and in vitro.

MATERIALS/METHODS

Human adipose tissue-derived mesenchymal stem cells (hAMSCs) were cultured with adipogenic differentiation media with or without AF. Male C57BL/6J mice (n=5 per group) were fed a high-fat diet (HFD) for six weeks with or without AF. Brown preadipocytes from the interscapular BAT of mice were cultured with or without AF.

RESULTS

In white adipogenic differentiation of hAMSCs, AF treatment significantly reduced the formation of lipid droplets and the expression of adipogenesis-related genes. In HFD-induced obese C57BL/6J mice, AF treatment significantly reduced body weight gain as well as the weights of the white adipose tissue, liver and spleen. Furthermore, AF induced the expression of genes involved in thermogenic function in BAT. In primary brown adipocytes, AF effectively stimulated the expressions of thermogenic genes and markedly up-regulated the AMP-activated protein kinase (AMPK) signaling pathway. Pretreatment with phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 nullified the induction of the thermogenic genes by AF in primary brown adipocytes. Moreover, AF activated beige cell marker genes induced by the pharmacological activation of peroxisome proliferator-activated receptor γ in hAMSCs.

CONCLUSION

This study shows that AF prevents the development of obesity in hAMSCs and mice fed an HFD and that it is also capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes by AMPK and PI3K/AKT.

β-Lapachone suppresses the lung metastasis of melanoma via the MAPK signaling pathway

β-Lapachone is a natural quinone compound from Lapacho trees, which has various pharmacological effects such as anti-bacterial, anti-fungal, anti-viral, and anti-inflammatory activities. However, the effect of β-lapachone on metastasis of melanoma cells is unclear. In this study, β-lapachone reduced cell viability of metastatic melanoma cancer cell lines B16F10 and B16BL6 through induction of apoptosis via the mitogen-activated protein kinase (MAPK) pathway. Additionally, flow cytometry results showed that β-lapachone increased DNA content in the G0/G1 phase of the cell cycle. Analysis of the mechanisms of these events indicated that β-lapachone regulated the expression of Bcl-2, Bcl-xL, and Bax, resulting in the activation of caspase-3, -8, -9, and poly-ADP-ribose polymerase (PARP). Moreover, the β-lapachone-administered group showed significantly decreased lung metastasis in the experimental mouse model. In conclusion, our study demonstrates the inhibitory effect of β-lapachone on lung metastasis of melanoma cells and provides a new insight into the role of β-lapachone as a potential antitumor agent.

Increased Cellular NAD+ Level through NQO1 Enzymatic Action Has Protective Effects on Bleomycin-Induced Lung Fibrosis in Mice

Background

Idiopathic pulmonary fibrosis is a common interstitial lung disease; it is a chronic, progressive, and fatal lung disease of unknown etiology. Over the last two decades, knowledge about the underlying mechanisms of pulmonary fibrosis has improved markedly and facilitated the identification of potential targets for novel therapies. However, despite the large number of antifibrotic drugs being described in experimental pre-clinical studies, the translation of these findings into clinical practices has not been accomplished yet. NADH:quinone oxidoreductase 1 (NQO1) is a homodimeric enzyme that catalyzes the oxidation of NADH to NAD⁺ by various quinones and thereby elevates the intracellular NAD⁺ levels. In this study, we examined the effect of increase in cellular NAD⁺ levels on bleomycin-induced lung fibrosis in mice.

Methods

C57BL/6 mice were treated with intratracheal instillation of bleomycin. The mice were orally administered with β-lapachone from 3 days before exposure to bleomycin to 1-3 weeks after exposure to bleomycin. Bronchoalveolar lavage fluid (BALF) was collected for analyzing the infiltration of immune cells. In vitro, A549 cells were treated with transforming growth factor β1 (TGF-β1) and β-lapachone to analyze the extracellular matrix (ECM) and epithelial-mesenchymal transition (EMT).

Results

β-Lapachone strongly attenuated bleomycin-induced lung inflammation and fibrosis, characterized by histological staining, infiltrated immune cells in BALF, inflammatory cytokines, fibrotic score, and TGF-β1, α-smooth muscle actin accumulation. In addition, β-lapachone showed a protective role in TGF-β1–induced ECM expression and EMT in A549 cells.

Conclusion

Our results suggest that β-lapachone can protect against bleomycin-induced lung inflammation and fibrosis in mice and TGF-β1–induced EMT in vitro, by elevating the NAD⁺/NADH ratio through NQO1 activation.

Arctigenin Inhibits Adipogenesis by Inducing AMPK Activation and Reduces Weight Gain in High-Fat Diet-Induced Obese Mice

Although arctigenin (ARC) has been reported to have some pharmacological effects such as anti-inflammation, anti-cancer, and antioxidant, there have been no reports on the anti-obesity effect of ARC. The aim of this study is to investigate whether ARC has an anti-obesity effect and mediates the AMP-activated protein kinase (AMPK) pathway. We investigated the anti-adipogenic effect of ARC using 3T3-L1 pre-adipocytes and human adipose tissue-derived mesenchymal stem cells (hAMSCs). In high-fat diet (HFD)-induced obese mice, whether ARC can inhibit weight gain was investigated. We found that ARC reduced weight gain, fat pad weight, and triglycerides in HFD-induced obese mice. ARC also inhibited the expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα) in in vitro and in vivo. Furthermore, ARC induced the AMPK activation resulting in down-modulation of adipogenesis-related factors including PPARγ, C/EBPα, fatty acid synthase, adipocyte fatty acid-binding protein, and lipoprotein lipase. This study demonstrates that ARC can reduce key adipogenic factors by activating the AMPK in vitro and in vivo and suggests a therapeutic implication of ARC for obesity treatment. J. Cell. Biochem. 117: 2067-2077, 2016. © 2016 Wiley Periodicals, Inc.

The fatty acid chain elongase, Elovl1, is required for kidney and swim bladder development during zebrafish embryogenesis

Very long chain fatty acids are required for sphingolipid synthesis, lipid homeostasis, myelin formation, epidermal permeability, and retinal function. Seven different enzymes are known to be involved in the elongation cycle of fatty acids, with different chain-length specificities. Elovl1 is one of those enzymes whose function has been linked mainly to the synthesis of sphingolipids and the epidermal barrier. However, the role of Elovl1 in organogenesis is not clear. In zebrafish, 2 Elovl1 genes, elovl1a and elovl1b, are highly expressed in the swim bladder, and elovl1b is also expressed in the kidney. We found that both elovl1 knockdown embryos contain increased levels of long chain fatty acids from carbon number 14 to 20 as compared to control embryos. Oil-Red-O staining shows that yolk lipid consumption is greatly reduced, whereas lipid droplets accumulate within the swim bladder. Notably, knockdown of either elovl1a or elovl1b affects the expression of genes involved in swim bladder development and impairs inflation of the swim bladder. Consistent with its expression in the pronephros, knockdown of elovl1b alone affects the expression of genes required for kidney development and reduces renal clearance. Our findings strongly suggest that both elovl1 genes are a key determinant of swim bladder and kidney development in zebrafish, which may be comparatively applicable to lung and kidney development in humans.

Niclosamide suppresses RANKL-induced osteoclastogenesis and prevents LPS-induced bone loss

Niclosamide (5-chloro-salicyl-(2-chloro-4-nitro) anilide) is an oral anthelmintic drug used for treating intestinal infection of most tapeworms. Recently, niclosamide was shown to have considerable efficacy against some tumor cell lines, including colorectal, prostate, and breast cancers, and acute myelogenous leukemia. Specifically, the drug was identified as a potent inhibitor of signal transducer and activator of transcription 3 (STAT3), which is associated with osteoclast differentiation and function. In this study, we assessed the effect of niclosamide on osteoclastogenesis in vitro and in vivo. Our in vitro study showed that receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast differentiation was inhibited by niclosamide, due to inhibition of serine-threonine protein kinase (Akt) phosphorylation, inhibitor of nuclear factor-kappaB (IκB), and STAT3 serine(727). Niclosamide decreased the expression of the major transcription factors c-Fos and NFATc1, and thereafter abrogated the mRNA expression of osteoclast-specific genes, including TRAP, OSCAR, αv/β3 integrin (integrin αv, integrin β3), and cathepsin K (CtsK). In an in vivo model, niclosamide prevented lipopolysaccharide-induced bone loss by diminishing osteoclast activity. Taken together, our results show that niclosamide is effective in suppressing osteoclastogenesis and may be considered as a new and safe therapeutic candidate for the clinical treatment of osteoclast-related diseases such as osteoporosis.

Cartilage development requires the function of Estrogen-related receptor alpha that directly regulates sox9 expression in zebrafish

Estrogen-related receptor alpha (ESRRa) regulates a number of cellular processes including development of bone and muscles. However, direct evidence regarding its involvement in cartilage development remains elusive. In this report, we establish an in vivo role of Esrra in cartilage development during embryogenesis in zebrafish. Gene expression analysis indicates that esrra is expressed in developing pharyngeal arches where genes necessary for cartilage development are also expressed. Loss of function analysis shows that knockdown of esrra impairs expression of genes including sox9, col2a1, sox5, sox6, runx2 and col10a1 thus induces abnormally formed cartilage in pharyngeal arches. Importantly, we identify putative ESRRa binding elements in upstream regions of sox9 to which ESRRa can directly bind, indicating that Esrra may directly regulate sox9 expression. Accordingly, ectopic expression of sox9 rescues defective formation of cartilage induced by the knockdown of esrra. Taken together, our results indicate for the first time that ESRRa is essential for cartilage development by regulating sox9 expression during vertebrate development.

Dunnione ameliorates cisplatin-induced small intestinal damage by modulating NAD(+) metabolism

Although cisplatin is a widely used anticancer drug for the treatment of a variety of tumors, its use is critically limited because of adverse effects such as ototoxicity, nephrotoxicity, neuropathy, and gastrointestinal damage. Cisplatin treatment increases oxidative stress biomarkers in the small intestine, which may induce apoptosis of epithelial cells and thereby elicit damage to the small intestine. Nicotinamide adenine dinucleotide (NAD(+)) is a cofactor for various enzymes associated with cellular homeostasis. In the present study, we demonstrated that the hyper-activation of poly(ADP-ribose) polymerase-1 (PARP-1) is closely associated with the depletion of NAD(+) in the small intestine after cisplatin treatment, which results in downregulation of sirtuin1 (SIRT1) activity. Furthermore, a decrease in SIRT1 activity was found to play an important role in cisplatin-mediated small intestinal damage through nuclear factor (NF)-κB p65 activation, facilitated by its acetylation increase. However, use of dunnione as a strong substrate for the NADH:quinone oxidoreductase 1 (NQO1) enzyme led to an increase in intracellular NAD(+) levels and prevented the cisplatin-induced small intestinal damage correlating with the modulation of PARP-1, SIRT1, and NF-κB. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological NQO1 substrates could be a promising therapeutic approach for protecting against cisplatin-induced small intestinal damage.

Dunnione ameliorates cisplatin ototoxicity through modulation of NAD(+) metabolism

Ototoxicity is an important issue in patients receiving cisplatin chemotherapy. Numerous studies have demonstrated that cisplatin-induced ototoxicity is related to oxidative stress and DNA damage. However, the precise mechanism underlying cisplatin-associated ototoxicity is still unclear. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as an important regulator of energy metabolism and cellular homeostasis. Here, we demonstrate that the levels and activities of sirtuin-1 (SIRT1) are suppressed by the reduction of intracellular NAD(+) levels in cisplatin-mediated ototoxicity. We provide evidence that the decreases in SIRT1 activity and expression facilitated by increasing poly(ADP-ribose) polymerase-1 (PARP-1) activation and microRNA-34a levels through cisplatin-mediated p53 activation aggravate the associated ototoxicity. Furthermore, we show that the induction of cellular NAD(+) levels using dunnione, which targets intracellular NQO1, prevents the toxic effects of cisplatin through the regulation of PARP-1 and SIRT1 activity. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological agents could be a promising therapeutic approach for protection from cisplatin-induced ototoxicity.

Nicotinamide adenine dinucleotide: An essential factor in preserving hearing in cisplatin-induced ototoxicity

Ototoxicity is an important issue in patients receiving cisplatin chemotherapy. Numerous studies have demonstrated that several mechanisms, including oxidative stress, DNA damage, and inflammatory responses, are closely associated with cisplatin-induced ototoxicity. Although much attention has been directed at identifying ways to protect the inner ear from cisplatin-induced damage, the precise underlying mechanisms have not yet been elucidated. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as an important regulator of cellular energy metabolism and homeostasis. NAD(+) acts as a cofactor for various enzymes including sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs), and therefore, maintaining adequate NAD(+) levels has therapeutic benefits because of its effect on NAD(+)-dependent enzymes. Recent studies demonstrated that disturbance in intracellular NAD(+) levels is critically involved in cisplatin-induced cochlear damage associated with oxidative stress, DNA damage, and inflammatory responses. In this review, we describe the importance of NAD(+) in cisplatin-induced ototoxicity and discuss potential strategies for the prevention or treatment of cisplatin-induced ototoxicity with a particular focus on NAD(+)-dependent cellular pathways.

Bucillamine prevents cisplatin-induced ototoxicity through induction of glutathione and antioxidant genes

Bucillamine is used for the treatment of rheumatoid arthritis. This study investigated the protective effects of bucillamine against cisplatin-induced damage in auditory cells, the organ of Corti from postnatal rats (P2) and adult Balb/C mice. Cisplatin increases the catalytic activity of caspase-3 and caspase-8 proteases and the production of free radicals, which were significantly suppressed by pretreatment with bucillamine. Bucillamine induces the intranuclear translocation of Nrf2 and thereby increases the expression of γ-glutamylcysteine synthetase (γ-GCS) and glutathione synthetase (GSS), which further induces intracellular antioxidant glutathione (GSH), heme oxygenase 1 (HO-1) and superoxide dismutase 2 (SOD2). However, knockdown studies of HO-1 and SOD2 suggest that the protective effect of bucillamine against cisplatin is independent of the enzymatic activity of HO-1 and SOD. Furthermore, pretreatment with bucillamine protects sensory hair cells on organ of Corti explants from cisplatin-induced cytotoxicity concomitantly with inhibition of caspase-3 activation. The auditory-brainstem-evoked response of cisplatin-injected mice shows marked increases in hearing threshold shifts, which was markedly suppressed by pretreatment with bucillamine in vivo. Taken together, bucillamine protects sensory hair cells from cisplatin through a scavenging effect on itself, as well as the induction of intracellular GSH.

Cisplatin-induced Kidney Dysfunction and Perspectives on Improving Treatment Strategies

Cisplatin is one of the most widely used and highly effective drug for the treatment of various solid tumors; however, it has dose-dependent side effects on the kidney, cochlear, and nerves. Nephrotoxicity is the most well-known and clinically important toxicity. Numerous studies have demonstrated that several mechanisms, including oxidative stress, DNA damage, and inflammatory responses, are closely associated with cisplatin-induced nephrotoxicity. Even though the establishment of cisplatin-induced nephrotoxicity can be alleviated by diuretics and pre-hydration of patients, the prevalence of cisplatin nephrotoxicity is still high, occurring in approximately one-third of patients who have undergone cisplatin therapy. Therefore it is imperative to develop treatments that will ameliorate cisplatin-nephrotoxicity. In this review, we discuss the mechanisms of cisplatin-induced renal toxicity and the new strategies for protecting the kidneys from the toxic effects without lowering the tumoricidal activity.

Rubi Fructus (Rubus coreanus) activates the expression of thermogenic genes in vivo and in vitro

OBJECTIVE

To investigate the anti-obesity effect of Rubi Fructus (RF) extract using brown adipose tissue (BAT) and primary brown preadipocytes in vivo and in vitro.

METHODS

Male C57BL/6 J mice (n=5 per group) were fed a high-fat diet (HFD) for 10 weeks with or without RF. Brown preadipocytes from the interscapular BAT of mice (age, post-natal days 1-3) were cultured with differentiation media (DM) including isobutylmethylxanthine, dexamethasone, T3, indomethacin and insulin with or without RF.

RESULTS

In HFD-induced obese C57BL/6 J mice, long-term RF treatment significantly reduced weight gain as well as the weights of the white adipose tissue, liver and spleen. Serum levels of total cholesterol and low-density lipoprotein cholesterol were also reduced in the HFD group which received RF treatment. Furthermore, RF induced thermogenic-, adipogenic- and mitochondria-related gene expressions in BAT. In primary brown adipocytes, RF effectively stimulated the expressions of thermogenic- and mitochondria-related genes. In addition, to examine whether LIPIN1, a regulator of adipocyte differentiation, is regulated by RF, Lipin1 small interfering RNA (siRNA) and RF were pretreated in primary brown adipocytes. Pretreatment with Lipin1 siRNA and RF downregulated the DM-induced expression levels of thermogenic- and mitochondria-related genes. Moreover, RF markedly upregulated AMP-activated protein kinase. Our study shows that RF is capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes.

CONCLUSIONS

This study demonstrates that RF prevents the development of obesity in mice fed with a HFD and that it is also capable of stimulating the differentiation of brown adipocytes through the modulation of thermogenic genes, which suggests that RF has potential as a therapeutic application for the treatment or prevention of obesity.

NAD(+) Metabolism in Age-Related Hearing Loss

Age-related hearing loss (ARHL), a degenerative disorder characterized by age-dependent progressive increase in the threshold of auditory sensitivity, affects 40% of people over the age of 65, and it has emerged as an important social and public health problem. Various factors, including genetic and environmental components, are known to affect both the onset and severity of ARHL. In particular, age-dependent changes in cellular oxidative stress and inflammatory responses accompanied by altered cellular signaling and gene expression progressively affect the function of the auditory system and eventually lead to hearing impairment. Recent findings suggest that a disturbance of intracellular NAD(+) levels is clinically related to the progression of age-associated disorders. Therefore, maintenance of optimal intracellular NAD(+) levels may be a critical factor for cellular senescence, and thus, understanding its molecular signaling pathways would provide critical insights into the prevention and treatment of ARHL as well as other age-related diseases. In this review, we describe the role of NAD(+) metabolism in aging and age-related diseases, including ARHL, and discuss a potential strategy for prevention or treatment of ARHL with a particular interest in NAD(+)-dependent cellular pathways.

The role of autophagy induced by pemetrexed in lung adenocarcinoma cells

Autophagy is known as an important regulatory mediator for cell survival or death and its important role in cancer. Pemetrexed (PTX) has been used in chemotherapy for lung cancer. However, the underlying molecular mechanisms have not been fully clarified. To investigate the role of autophagy induced by PTX in A549 cells, we performed MTT assay, acridine orange staining, western blotting, Annexin V/PI by using the 3-MA autophagy inhibitor. PTX induced autophagy after 48 h treatment in A549 cells. Furthermore, PTX showed acidic vesicular organelles (AVOs) and expressed LC3-II in A549 cells. The induction of autophagy by PTX was inhibited by 3-MA which was confirmed by reduced AVOs. When the autophagy was inhibited, Annexin V was increased. In addition, PARP cleavage was increased as shown by western blotting. Taken together, PTX induced autophagy in A549 cells and these cellular events possibly cause the apoptotic and/or necrotic cell death of A549 cells.

Capsaicin ameliorates cisplatin-induced renal injury through induction of heme oxygenase-1

Cisplatin is one of the most potent chemotherapy agents. However, its use is limited due to its toxicity in normal tissues, including the kidney and ear. In particular, nephrotoxicity induced by cisplatin is closely associated with oxidative stress and inflammation. Heme oxygenase-1 (HO-1), the rate-limiting enzyme in the heme metabolism, has been implicated in a various cellular processes, such as inflammatory injury and anti-oxidant/oxidant homeostasis. Capsaicin is reported to have therapeutic potential in cisplatin-induced renal failures. However, the mechanisms underlying its protective effects on cisplatin-induced nephrotoxicity remain largely unknown. Herein, we demonstrated that administration of capsaicin ameliorates cisplatin-induced renal dysfunction by assessing the levels of serum creatinine and blood urea nitrogen (BUN) as well as tissue histology. In addition, capsaicin treatment attenuates the expression of inflammatory mediators and oxidative stress markers for renal damage. We also found that capsaicin induces HO-1 expression in kidney tissues and HK-2 cells. Notably, the protective effects of capsaicin were completely abrogated by treatment with either the HO inhibitor ZnPP IX or HO-1 knockdown in HK-2 cells. These results suggest that capsaicin has protective effects against cisplatin-induced renal dysfunction through induction of HO-1 as well as inhibition oxidative stress and inflammation.

Visceral adipose tissue is significantly associated with hearing thresholds in adult women

OBJECTIVE

Metabolic syndrome is a risk factor for age-related hearing impairment (ARHI). There are metabolic differences between abdominal adipose tissue present in subcutaneous and visceral areas. In this study, we investigated the association between abdominal fat composition, measured by computerized tomography (CT), and hearing thresholds.

PATIENTS AND METHODS

We recruited 662 adults aged 40-82 years with normal or symmetrical sensorineural hearing loss who underwent fat measurement by CT. Linear regression models were used to address the association between risk factors, including abdominal fat composition, and average hearing levels at low and high frequencies.

RESULTS

After adjusting for age, systemic disease and other variables, a positive association between visceral adipose tissue (VAT) area and average hearing threshold was observed in women. In men, there was no significant association between abdominal fat composition and hearing threshold.

CONCLUSION

Our findings show an association between VAT and hearing impairment in women. A reduction in visceral adiposity may help to prevent hearing loss in women.

Activation of β-catenin by inhibitors of glycogen synthase kinase-3 ameliorates cisplatin-induced cytotoxicity and pro-inflammatory cytokine expression in HEI-OC1 cells

Cisplatin is used in the treatment of a wide variety of solid tumors, but its use is limited by its serious adverse effects, including ototoxicity. Glycogen synthase kinase-3 (GSK-3) is a ubiquitously expressed serine/threonine kinase that regulates a variety of cellular functions by phosphorylating its substrates. However, the otoprotective effect of GSK-3 inhibitors is poorly understood. Here, we investigated whether GSK-3 is involved in cisplatin-induced ototoxicity in HEI-OC1 cells and organs of Corti (OCs). GSK-3 inhibitors suppressed cisplatin-induced apoptosis determined by decreased p53 activity, and also decreased expression of PARP and p53 target genes such as p21 and PUMA. The effect of GSK-3 inhibitors was mediated by markedly increased nuclear β-catenin that in turn blocked nuclear translocation of NF-κB. siRNA-mediated β-catenin knockdown markedly increased the expression of NF-κB target genes, such as TNF-α and IL-6. Our data suggest that the GSK-3/β-catenin pathway may play a central role in cisplatin-mediated cytotoxicity in HEI-OC1 cells and hair cells of OCs in vitro.

Developmental roles of D-bifunctional protein-A zebrafish model of peroxisome dysfunction

The peroxisome is an intracellular organelle that responds dynamically to environmental changes. Various model organisms have been used to study the roles of peroxisomal proteins in maintaining cellular homeostasis. By taking advantage of the zebrafish model whose early stage of embryogenesis is dependent on yolk components, we examined the developmental roles of the D-bifunctional protein (Dbp), an essential enzyme in the peroxisomal β-oxidation. The knockdown of dbp in zebrafish phenocopied clinical manifestations of its deficiency in human, including defective craniofacial morphogenesis, growth retardation, and abnormal neuronal development. Overexpression of murine Dbp rescued the morphological phenotypes induced by dbp knockdown, indicative of conserved roles of Dbp during zebrafish and mammalian development. Knockdown of dbp impaired normal development of blood, blood vessels, and most strikingly, endoderm-derived organs including the liver and pancreas - a phenotype not reported elsewhere in connection with peroxisome dysfunction. Taken together, our results demonstrate for the first time that zebrafish might be a useful model animal to study the role of peroxisomes during vertebrate development.

Autophagy induction by low-dose cisplatin: the role of p53 in autophagy

The majority of chemotherapy treatments for lung cancer use cisplatin; however, its use is limited as it has several side-effects. Autophagy (or type II cell death) is an important mechanism by which programmed cell death occurs. The purpose of this study was to determine whether low-dose cisplatin treatment induces autophagy in lung cancer cells. We also examined whether autophagy inhibition results in p53-mediated apoptosis. NCI-H460 (wild-type p53) and NCI-H1299 (null-type p53) cells were treated with 5 or 20 µM cisplatin for 12, 24 or 48 h. An MTT assay was performed to measure the cell viability following cisplatin treatment. To detect cisplatin-induced autophagy, cell morphology (autophagic vacuole) and LC3 localization were examined. The outcome of autophagy inhibition was determined using 3-methyladenine (3-MA) to detect Annexin V (+), propidium iodide (PI) (-) and acridine orange (+) cells by FACS analysis. To determine whether cisplatin induced autophagy, we examined the role of p53 as a cell survival regulator in autophagy. Low-doses of cisplatin (5 µM) induced cell death and this was augmented by 3-MA in both cell lines. Autophagic vacuoles and cytoplasmic LC3 formation was more evident in H460 cells than in H1299 cells. The induction of autophagy by low-dose cisplatin was increased by 2-fold in H460 compared to H1299 cells. However, the tests for apoptosis showed no difference between the 2 cell lines. Following 3-MA pretreatment, cisplatin-induced autophagy was found to be markedly reduced (a 3-fold reduction) in wild-type p53 compared to null-type p53 cells. However, cisplatin-induced apoptosis increased in wild-type p53 compared to null-type p53 cells. Autophagy induction and apoptotic shift after autophagy inhibition may be mediated by p53 activation in lung cancer cells treated with low-dose cisplatin.

Pharmacological activation of NQO1 increases NAD⁺ levels and attenuates cisplatin-mediated acute kidney injury in mice

Cisplatin is a widely used chemotherapeutic agent for the treatment of various tumors. In addition to its antitumor activity, cisplatin affects normal cells and may induce adverse effects, such as ototoxicity, nephrotoxicity, and neuropathy. Various mechanisms, such as DNA adduct formation, mitochondrial dysfunction, oxidative stress, and inflammatory responses, are critically involved in cisplatin-induced adverse effects. As NAD⁺ is a cofactor for various enzymes associated with cellular homeostasis, we studied the effects of increased NAD⁺ levels by means of NAD(P)H:quinone oxidoreductase 1 (NQO1) activation using a known pharmacological activator (β-lapachone) in wild-type and NQO1^−/− mice on cisplatin-induced renal dysfunction in vivo. The intracellular NAD⁺/NADH ratio in renal tissues was significantly increased in wild-type mice co-treated with cisplatin and β-lapachone compared with the ratio in mice treated with cisplatin alone. Inflammatory cytokines and biochemical markers for renal damage were significantly attenuated by β-lapachone co-treatment compared with those in the cisplatin alone group. Notably, the protective effects of β-lapachone in wild-type mice were completely abrogated in NQO1^−/− mice. Moreover, β-lapachone enhanced the tumoricidal action of cisplatin in a xenograft tumor model. Thus, intracellular regulation of NAD⁺ levels through NQO1 activation might be a promising therapeutic target for the protection of cisplatin-induced acute kidney injury.

Curculigo orchioides protects cisplatin-induced cell damage

Cisplatin is commonly used as a chemotherapeutic agent against many human cancers. However, it generates reactive oxygen species (ROS) and has serious dose-limiting side effects, including ototoxicity. The roots of Curculigo orchioides (C. orchioides) have been used to treat auditory diseases such as tinnitus and hearing loss in Chinese traditional medicine. In the present study, we investigated the protective effects of an ethanol extract obtained from C. orchioides rhizome (COR) on cisplatin-induced cell damage in auditory cells (HEI-OC1). COR (2.5-25 μg/ml) inhibited cisplatin-induced HEI-OC1 cell damage in a dose-dependent manner. To investigate the protective mechanism of COR on cisplatin cytotoxicity in HEI-OC1 cells, we measured the effects of COR on ROS generation and lipid peroxidation in cisplatin-treated cells as well as its scavenging activities against superoxide radicals, hydroxyl radicals, hydrogen peroxide, and DPPH radicals. COR (1-25 μg/ml) had scavenging activities against superoxide radicals, hydroxyl radicals, hydrogen peroxide, and DPPH radicals, as well as reduced lipid peroxidation. In in vivo experiments, COR was shown to reduce cochlear and peripheral auditory function impairments through cisplatin-induced auditory damage in mice. These results indicate that COR protects from cisplatin-induced auditory damage by inhibiting lipid peroxidation and scavenging activities against free radicals.

Red ginseng protects against gentamicin-induced balance dysfunction and hearing loss in rats through antiapoptotic functions of ginsenoside Rb1

The authors evaluated the protective effects of Korean red ginseng (KRG) against gentamicin (GM)-induced unilateral vestibular and hearing dysfunction and investigated its effective mechanism using in vitro cell cultures. Vestibular function was comprehensively evaluated by a scoring system that ranged from 0 (normal) to 3 (worst) points, using head tilt, tail hanging, and swimming tests. The GM group showed significantly more deteriorated vestibular function (0 point--5 rats, 1 point--1 rat, 2 points--3 rats, and 3 points--3 rats) than the KRG+GM group (0 point--9 rats and 1 point--1 rat) (p<0.01). The hearing thresholds were better in the KRG+GM group than in the GM group (p<0.05). Quantitative analysis of hair cell damage in the scanning electron microscopy was closely related with vestibular and hearing functional results. In vitro study showed that ginsenoside Rb1 (gRb1) attenuated reactive oxygen species production, suppressed JNK activation, up-regulated Bcl-xL and down-regulated Bax, cytochrome c, caspase 3, and cleaved poly (ADP-ribose) polymerase in GM-treated VOT-E36 cells. These findings suggest that KRG including gRb1 component protects against vestibular/hearing dysfunction by inhibiting apoptotic pathways when ototoxicity is induced by unilateral intratympanic injection with GM in rats.

Impact of Nucleotide Mutations at the HNF3- and HNF4-Binding Sites in Enhancer 1 on Viral Replication in Patients with Chronic Hepatitis B Virus Infection

Background/Aims

The hepatitis B virus (HBV) genome contains binding sites for hepatocyte nuclear factors (HNF) 3 and 4 in the core domain of enhancer 1 (Enh1), and mutations in this domain have a strong impact on virus replication. We aimed to identify frequent base-mutation sites in the core domain of Enh1 and to examine the impact of these mutations on viral replication.

Methods

We studied virological characteristics and genetic sequences in 387 patients with chronic hepatitis B. We evaluated functional differences associated with specific mutations within the core domain of Enh1.

Results

Mutations in the core domain were found with significant frequency in C1126 (122/387 [31.5%], the binding site for HNF3) and in C1134 (106/387 [27.4%], the binding site for HNF4). A single mutation at nt 1126 (C1126) was identified in 17/123 (13.8%), and 105/123 (85.4%) had double mutations (C1126/1134). The level of HBV DNA (log10 copies/mL) was lower in single mutants (C1126, 5.81±1.25) than in wild (6.80±1.65) and double mutants (C1126/1134, 6.81±1.54). Similarly, the relative luciferase activity of C1126 and C1126/C1134 was 0.18 and 1.12 times that of the wild-type virus, respectively.

Conclusions

Mutations in the HNF3 binding site inhibit viral replication, whereas mutations at the HNF4 binding site restore viral replication.

Serum YKL-40 levels correlate with infarct volume, stroke severity, and functional outcome in acute ischemic stroke patients

Background and Purpose

YKL-40 is associated with various neurological disorders. However, circulatory YKL-40 levels early after onset of acute ischemic stroke (AIS) have not been systematically assessed. We aimed to identify the temporal changes and clinical usefulness of measuring serum YKL-40 immediately following AIS.

Methods

Serum YKL-40 and C-reactive protein (CRP) levels were monitored over time in AIS patients (n = 105) and compared with those of stroke-free controls (n = 34). Infarct volume and stroke severity (National Institutes of Health Stroke Scale; NIHSS) were measured within 48 hours of symptom onset, and functional outcome (modified Rankin Scale; mRS) was measured 3 months after AIS.

Results

Within 12 hours of symptom onset, levels of YKL-40 (251 vs. 41 ng/mL) and CRP (1.50 vs. 0.96 µg/mL) were elevated in AIS patients compared to controls. The power of YKL-40 for discriminating AIS patients from controls was superior to that of CRP (area under the curve 0.84 vs. 0.64) and YKL-40 (r = 0.26, P<0.001) but not CRP levels were correlated with mRS. On day 2 of admission (D2), YKL-40 levels correlated with infarct volume and NIHSS. High YKL-40 levels predicted poor functional outcome (odds ratio 5.73, P = 0.03). YKL-40 levels peaked on D2 and declined on D3, whereas CRP levels were highest on D3.

Conclusions

Our results demonstrate serial changes in serum YKL-40 levels immediately following AIS and provide the first evidence that it is a valid indicator of AIS extent and an early predictor of functional outcome.

(-)-Epigallocatechin-3-gallate protects against NO-induced ototoxicity through the regulation of caspase- 1, caspase-3, and NF-κB activation

Excessive nitric oxide (NO) production is toxic to the cochlea and induces hearing loss. However, the mechanism through which NO induces ototoxicity has not been completely understood. The aim of this study was to gain further insight into the mechanism mediating NO-induced toxicity in auditory HEI-OC1 cells and in ex vivo analysis. We also elucidated whether and how epigallocatechin-3-gallate (EGCG), the main component of green tea polyphenols, regulates NO-induced auditory cell damage. To investigate NO-mediated ototoxicity, S-nitroso-N-acetylpenicillamine (SNAP) was used as an NO donor. SNAP was cytotoxic, generating reactive oxygen species, releasing cytochrome c, and activating caspase-3 in auditory cells. NO-induced ototoxicity also mediated the nuclear factor (NF)-κB/caspase-1 pathway. Furthermore, SNAP destroyed the orderly arrangement of the 3 outer rows of hair cells in the basal, middle, and apical turns of the organ of Corti from the cochlea of Sprague-Dawley rats at postnatal day 2. However, EGCG counteracted this ototoxicity by suppressing the activation of caspase-3/NF-κB and preventing the destruction of hair cell arrays in the organ of Corti. These findings may lead to the development of a model for pharmacological mechanism of EGCG and potential therapies against ototoxicity.

Rehmannia glutinosaActivates Intracellular Antioxidant Enzyme Systems in Mouse Auditory Cells

Steamed roots of Rehmannia glutinosa (R. glutinosa) have been traditionally used in Oriental medicine for the treatment of auditory diseases such as tinnitus and hearing loss. To investigate whether the ethanol extract of steamed roots of R. glutinosa (SRG) increases activity of antioxidant enzymes and the level of glutathione (GSH), we measured activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR) and GSH level in HEI-OC1 cells after treatment with 5–50 μg/ml of SRG. The SOD and CAT activities were significantly increased in the presence of SRG compared to the control group. Maximal activities of SOD and CAT were observed in these cells exposed to 10 μg/ml of SRG. The GPX activity also increased dramatically in response to the treatment with SRG in a dose-dependent manner. The GR activity was only increased in the presence of 50 μg/ml of SRG compared to the control group. The level of GSH gradually increased in the presence of 5–50 μg/ml of SRG. In the cytotoxicity test, 5–50 μg/ml of SRG did not show any significant cytotoxicity. These results suggest that the traditional use of R. glutinosa for the treatment of auditory diseases may be explained, in part, by activation of intracellular antioxidant enzyme systems. Further studies are necessary to clarify the active constituents of SRG responsible for such biomolecular activities.

Protective Effect of a Chrysanthemum indicum containing Formulation in Cadmium-Induced Ototoxicity

Chungshinchongyitang (CSCYT) is an herbal drug formula containing Chrysanthemum indicum and 13 other herbs used for treating auditory diseases. Irreversible hearing loss is a characteristic effect of a number of heavy metals. Cadmium ( Cd2+ ) is an environmental contaminant that causes a variety of adverse effects. In the present study, we investigate the protective effects of CSCYT against Cd2+ induced ototoxicity in vitro and ex vivo. The findings of this study show that CSCYT prevents the destruction of hair cell arrays induced by Cd2+ in the rat organ of Corti primary explants. CSCYT inhibited cell death, release of cytochrome c and generation of reactive oxygen species induced by Cd2+ in HEI-OC1 auditory cell line. In addition, we also demonstrated that CSCYT exerted its effect by modulating of apoptosis via the caspase-3 activation and extracellular signal-regulated kinase activation. These results are expected to improve the understanding of the pharmacological mechanism of CSCYT and aid in the development of potential therapeutic strategies against ototoxicity.

Interaction of Ets-1 with HDAC1 represses IL-10 expression in Th1 cells

IL-10 is a multifunctional cytokine that plays a crucial role in immunity and tolerance. IL-10 is produced by diverse immune cell types, including B cells and subsets of T cells. Although Th1 produce IL-10, their expression levels are much lower than Th2 cells under conventional stimulation conditions. The potential role of E26 transformation-specific 1 (Ets-1) transcription factor as a negative regulator for Il10 gene expression in CD4(+) T cells has been implicated previously. In this study, we investigated the underlying mechanism of Ets-1-mediated Il10 gene repression in Th1 cells. Compared with wild type Th1 cells, Ets-1 knockout Th1 cells expressed a significantly higher level of IL-10, which is comparable with that of wild type Th2 cells. Upregulation of IL-10 expression in Ets-1 knockout Th1 cells was accompanied by enhanced chromatin accessibility and increased recruitment of histone H3 acetylation at the Il10 regulatory regions. Reciprocally, Ets-1 deficiency significantly decreased histone deacetylase 1 (HDAC1) enrichment at the Il10 regulatory regions. Treatment with trichostatin A, an inhibitor of HDAC family, significantly increased Il10 gene expression by increasing histone H3 acetylation recruitment. We further demonstrated a physical interaction between Ets-1 and HDAC1. Coexpression of Ets-1 with HDAC1 synergistically repressed IL-10 transcription activity. In summary, our data suggest that an interaction of Ets-1 with HDAC1 represses the Il10 gene expression in Th1 cells.

2',4',6'-Tris(methoxymethoxy) chalcone (TMMC) attenuates the severity of cerulein-induced acute pancreatitis and associated lung injury

Acute pancreatitis (AP) is an inflammatory disease involving acinar cell injury and rapid production and release of inflammatory cytokines, which play a dominant role in local pancreatic inflammation and systemic complications. 2',4',6'-Tris (methoxymethoxy) chalcone (TMMC), a synthetic chalcone derivative, displays potent anti-inflammatory effects. Therefore, we aimed to investigate whether TMMC might affect the severity of AP and pancreatitis-associated lung injury in mice. We used the cerulein hyperstimulation model of AP. Severity of pancreatitis was determined in cerulein-injected mice by histological analysis and neutrophil sequestration. The pretreatment of mice with TMMC reduced the severity of AP and pancreatitis-associated lung injury and inhibited several biochemical parameters (activity of amylase, lipase, trypsin, trypsinogen, and myeloperoxidase and production of proinflammatory cytokines). In addition, TMMC inhibited pancreatic acinar cell death and production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 by inhibiting NF-κB and extracellular signal-regulated protein kinase 1/2 (ERK1/2) activation. Neutralizing antibodies for TNF-α, IL-1β, and IL-6 inhibited cerulein-induced cell death in isolated pancreatic acinar cells. Moreover, pharmacological blockade of NF-κB/ERK1/2 reduced acinar cell death and production of TNF-α, IL-1β, and IL-6 in isolated pancreatic acinar cells. In addition, posttreatment of mice with TMMC showed reduced severity of AP and lung injury. Our results suggest that TMMC may reduce the complications associated with pancreatitis.

Berberine-induced apoptosis in human glioblastoma T98G cells is mediated by endoplasmic reticulum stress accompanying reactive oxygen species and mitochondrial dysfunction

Berberine has a wide range of biochemical and pharmacologic effects, including antitumor activity, but the mechanisms involved in berberine-induced apoptosis remain unclear. The purpose of the present study was to investigate the changes in oxidative stress and endoplasmic reticulum (ER)-related molecules, which are closely associated with cell death-signaling transduction pathways, in human glioblastoma T98G cells treated with berberine. Berberine significantly decreased the cell viability of T98G cells in a dose-dependent manner. Berberine increased the production of reactive oxygen species (ROS) and level of intracellular Ca(2+). Berberine induced ER stress as evidenced by the detection of ER stress-associated molecules such as phosphorylated protein kinase-like ER kinase, eukaryotic translation initiation factor-2α, glucose-regulated protein 78/immunoglobulin heavy chain-binding protein, and CCAAT/enhancer-binding protein (C/EBP)-homologous protein/growth arrest and DNA damage-inducible gene 153, which was associated with the activation of caspase-3. Furthermore, the administration of the antioxidants, N-acetylcysteine and glutathione, reversed berberine-induced apoptosis. Berberine also markedly enhanced apoptosis in T98G cells through the induction of a higher ratio of Bax/Bcl-2 proteins, disruption of the mitochondrial membrane potential, activation of caspase-9 and -3, and cleavage of the poly(ADP-ribose) polymerase (PARP). The inhibition of ER stress using salubrinal led to an increased the level of Bcl-2, whereas the level of Bax, cleavage of procaspase-9 and -3, and PARP were decreased when compared with cells treated with berberine alone, indicating that berberine-induced apoptosis is associated with mitochondrial dysfunction. These results demonstrate that berberine induces apoptosis via ER stress through the elevation of ROS and mitochondrial-dependent pathway in human glioblastoma T98G cells.

Cisplatin ototoxicity involves cytokines and STAT6 signaling network

We herein investigated the role of the STAT signaling cascade in the production of pro-inflammatory cytokines and cisplatin ototoxicity. A significant hearing impairment caused by cisplatin injection was observed in Balb/c (wild type, WT) and STAT4(-/-), but not in STAT6(-/-) mice. Moreover, the expression levels of the protein and mRNA of pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6, were markedly increased in the serum and cochlea of WT and STAT4(-/-), but not STAT6(-/-) mice. Organotypic culture revealed that the shape of stereocilia bundles and arrays of sensory hair cell layers in the organ of Corti from STAT6(-/-) mice were intact after treatment with cisplatin, whereas those from WT and STAT4(-/-) mice were highly distorted and disarrayed after the treatment. Cisplatin induced the phosphorylation of STAT6 in HEI-OC1 auditory cells, and the knockdown of STAT6 by STAT6-specific siRNA significantly protected HEI-OC1 auditory cells from cisplatin-induced cell death and inhibited pro-inflammatory cytokine production. We further demonstrated that IL-4 and IL-13 induced by cisplatin modulated the phosphorylation of STAT6 by binding with IL-4 receptor alpha and IL-13Rα1. These findings suggest that STAT6 signaling plays a pivotal role in cisplatin-mediated pro-inflammatory cytokine production and ototoxicity.

Up-regulation of hypoxia-inducible factor-1 alpha by cobalt chloride prevents hearing loss in noise-exposed mice

Since hypoxia-inducible factor-1α (HIF-1α) is the key transcription factor that enables cells to survive in hypoxia, we have investigated whether an upregulation of HIF-1α prevents the noise-induced hearing loss in BALB/c hybrid mice, which were intraperitoneally injected with CoCl(2) (a HIF-1α inducer) and exposed to white band noise with 120 dB peak equivalent sound pressure level for 3h once daily for 3 days. In the CoCl(2) treatment group, HIF-1α was found to be up-regulated in the cochlear tissues and the hearing loss was largely prevented. Histologically, the loss of sensory hair cells was also significantly lower in the CoCl(2) treatment group than the Control group. However, YC-1 (a HIF-1α inhibitor) attenuated the preventive effect of CoCl(2) on the noise-induced hearing loss. These results suggest that HIF-1α plays a crucial role in the prevention against noise trauma in the inner ear.