TRAF6 Restricts p53 Mitochondrial Translocation, Apoptosis, and Tumor Suppression.

Mitochondrial p53 is involved in apoptosis and tumor suppression. However, its regulation is not well studied. Here, we show that TRAF6 E3 ligase is a crucial factor to restrict mitochondrial translocation of p53 and spontaneous apoptosis by promoting K63-linked ubiquitination of p53 at K24 in cytosol, and such ubiquitination limits the interaction between p53 and MCL-1/BAK. Genotoxic stress reduces this ubiquitination in cytosol by S13/T330 phosphorylation-dependent translocation of TRAF6 from cytosol to nucleus, where TRAF6 also facilitates the K63-linked ubiquitination of nuclear p53 and its transactivation by recruiting p300 for p53 acetylation. Functionally, K63-linked ubiquitination of p53 compromised p53-mediated apoptosis and tumor suppression. Colorectal cancer samples with WT p53 reveal that TRAF6 overexpression negatively correlates with apoptosis and predicts poor response to chemotherapy and radiotherapy. Together, our study identifies TRAF6 as a critical gatekeeper to restrict p53 mitochondrial translocation, and such mechanism may contribute to tumor development and drug resistance.

Tafenoquine and its derivatives as inhibitors for the severe acute respiratory syndrome coronavirus 2.

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has severely affected human lives around the world as well as the global economy. Therefore, effective treatments against COVID-19 are urgently needed. Here, we screened a library containing Food and Drug Administration (FDA)-approved compounds to identify drugs that could target the SARS-CoV-2 main protease (Mpro), which is indispensable for viral protein maturation and regard as an important therapeutic target. We identified antimalarial drug tafenoquine (TFQ), which is approved for radical cure of Plasmodium vivax and malaria prophylaxis, as a top candidate to inhibit Mpro protease activity. The crystal structure of SARS-CoV-2 Mpro in complex with TFQ revealed that TFQ noncovalently bound to and reshaped the substrate-binding pocket of Mpro by altering the loop region (residues 139-144) near the catalytic Cys145, which could block the catalysis of its peptide substrates. We also found that TFQ inhibited human transmembrane protease serine 2 (TMPRSS2). Furthermore, one TFQ derivative, compound 7, showed a better therapeutic index than TFQ on TMPRSS2 and may therefore inhibit the infectibility of SARS-CoV-2, including that of several mutant variants. These results suggest new potential strategies to block infection of SARS-CoV-2 and rising variants.

Skp2-Mediated RagA Ubiquitination Elicits a Negative Feedback to Prevent Amino-Acid-Dependent mTORC1 Hyperactivation by Recruiting GATOR1.

The regulation of RagA(GTP) is important for amino-acid-induced mTORC1 activation. Although GATOR1 complex has been identified as a negative regulator for mTORC1 by hydrolyzing RagA(GTP), how GATOR1 is recruited to RagA to attenuate mTORC1 signaling remains unclear. Moreover, how mTORC1 signaling is terminated upon amino acid stimulation is also unknown. We show that the recruitment of GATOR1 to RagA is induced by amino acids in an mTORC1-dependent manner. Skp2 E3 ligase drives K63-linked ubiquitination of RagA, which facilitates GATOR1 recruitment and RagA(GTP) hydrolysis, thereby providing a negative feedback loop to attenuate mTORC1 lysosomal recruitment and prevent mTORC1 hyperactivation. We further demonstrate that Skp2 promotes autophagy but inhibits cell size and cilia growth through RagA ubiquitination and mTORC1 inhibition. We thereby propose a negative feedback whereby Skp2-mediated RagA ubiquitination recruits GATOR1 to restrict mTORC1 signaling upon sustained amino acid stimulation, which serves a critical mechanism to maintain proper cellular functions.

Your height affects your health: genetic determinants and health-related outcomes in Taiwan.

BACKGROUND: Height is an important anthropometric measurement and is associated with many health-related outcomes. Genome-wide association studies (GWASs) have identified hundreds of genetic loci associated with height, mainly in individuals of European ancestry. METHODS: We performed genome-wide association analyses and replicated previously reported GWAS-determined single nucleotide polymorphisms (SNPs) in the Taiwanese Han population (Taiwan Biobank; n = 67,452). A genetic instrument composed of 251 SNPs was selected from our GWAS, based on height and replication results as the best-fit polygenic risk score (PRS), in accordance with the clumping and p-value threshold method. We also examined the association between genetically determined height (PRS251) and measured height (phenotype). We performed observational (phenotype) and genetic PRS251 association analyses of height and health-related outcomes. RESULTS: GWAS identified 6843 SNPs in 89 genomic regions with genome-wide significance, including 18 novel loci. These were the most strongly associated genetic loci (EFEMP1, DIS3L2, ZBTB38, LCORL, HMGA1, CS, and GDF5) previously reported to play a role in height. There was a positive association between PRS251 and measured height (p < 0.001). Of the 14 traits and 49 diseases analyzed, we observed significant associations of measured and genetically determined height with only eight traits (p < 0.05/[14 + 49]). Height was positively associated with body weight, waist circumference, and hip circumference but negatively associated with body mass index, waist-hip ratio, body fat, total cholesterol, and low-density lipoprotein cholesterol (p < 0.05/[14 + 49]). CONCLUSIONS: This study contributes to the understanding of the genetic features of height and health-related outcomes in individuals of Han Chinese ancestry in Taiwan.

Lupeol suppresses migration and invasion via p38/MAPK and PI3K/Akt signaling pathways in human osteosarcoma U-2 OS cells.

Lupeol, one of the common components from the fruits and natural foods, has been reported to exert antitumor activities in many human cancer cell lines; however, its effects on osteosarcoma cell metastasis were not elucidated. In the present study, lupeol at 10-25 µM induced cell morphological changes and decreased total viable cell number in U-2 OS cells. Lupeol (5-15 µM) suppressed cell mobility, migration, and invasion by wound healing and transwell chamber assays, respectively. Lupeol inhibited the activities of MMP-2 and -9 in U-2 OS cells by gelatin zymography assay. Lupeol significantly decreased PI3K, pAKT, ß-catenin, and increased GSK3ß. Furthermore, lupeol decreased the expressions of Ras, p-Raf-1, p-p38, and ß-catenin. Lupeol also decreased uPA, MMP-2, MMP-9, and N-cadherin but increased VE-cadherin in U-2 OS cells. Based on these observations, we suggest that lupeol can be used in anti-metastasis of human osteosarcoma cells in the future.

Cantharidin decreased viable cell number in human osteosarcoma U-2 OS cells through G2/M phase arrest and induction of cell apoptosis.

Cantharidin (CTD), a sesquiterpenoid bioactive substance, has been reported to exhibit anticancer activity against various types of cancer cells. The aim of the present study was to investigate the apoptosis effects and the underlying mechanisms of CTD on osteosarcoma U-2 OS cells. Results showed that CTD induced cell morphologic changes, reduced total viable cells, induced DNA damage, and G2/M phase arrest. CTD increased the production of reactive oxygen species and Ca2+, and elevated the activities of caspase-3 and -9, but decreased the level of mitochondrial membrane potential. Furthermore, CTD increased the ROS- and ER stress-associated protein expressions and increased the levels of pro-apoptosis-associated proteins, but decreased that of anti-apoptosis-associated proteins. Based on these observations, we suggested that CTD decreased cell number through G2/M phase arrest and the induction of cell apoptosis in U-2 OS cells and CTD could be a potential candidate for osteosarcoma treatments.

Anti-apoptotic effect of San Huang Shel Shin Tang cyclodextrin complex (SHSSTc) on CCl4 -induced hepatotoxicity in rats.

The metabolic loading is heavier in liver especially when injured or inflammation. San Huang Shel Shin Tang (SHSST) was an old traditional herbal decoction, which composed with Rheum officinale Baill, Scutellaria baicalnsis Geprgi and Coptis chinensis Franch (1:1:2 in weight), can provide a liver protection effects. We used a beta-cyclodextrin (ß-CD) drug modification method in reduce of the necessary dose of the SHSST. As the results, the FAS-FADD expressions leaded apoptosis in CCl4 intraperitoneal (IP) injection induced acute liver injury in rats. Silymarin, baicalein, SHSST, and SHSST ß-CD complex (SHSSTc) pretreatments protected liver through the decreasing of the expressions of FAS-FADD and downstream caspase-3 and caspase-8. Particularly, SHSSTc (30 mg/kg day) treatment enhanced cell survival pathway activation through the PI3K, Akt and Bad phosphorylation. Compared with SHSST as well as silymarin and baicalein, SHSSTc provided a magnificent liver protection effect, especially in survival pathway activation/TUNEL-apoptotic cell reduction/serum cholesterol level suppression. All these data suggested that ß-CD complex modified the SHSST and promoted the bioavailability and liver protection effects. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 663-670, 2016.

Lumbrokinase from earthworm extract ameliorates second-hand smoke-induced cardiac fibrosis.

Exposure to tobacco smoke has epidemiologically been linked to the occurrence of cardiovascular disease among nonsmokers but the associated molecular events are not well elucidated yet. When Sprague Dawley rats were exposed to second-hand tobacco cigarette smoke twice a day for a 30 days period at an exposure rate of 10 cigarettes/30 min, they showed adverse effects including reduced left ventricle weight, increased cardiac damages, deteriorated cardiac features, and cardiac fibrosis. Exposure to second-hand smoking (SHS) increased the molecular markers of cardiac fibrosis such as urokinase plasminogen activator and matrix metallopeptidases. The modulations in the protein levels were led by the activation of extracellular signal-regulated kinases (ERK1/2), the transcription factor-specificity protein 1 (SP1), and the fibrogenic master switch-connective for epithelial-mesenchymal transition tissue growth factor there by indicating their effective role in SHS-induced myocardial infraction. Dilong, an edible earthworm extract used in Chinese medicine and its bioactive fibrinolytic enzyme product-lumbrokinase, when administered in rats, restricted the SHS exposure induced cardiac fibrosis and provided cardio-protection. The results show that lumbrokinase and dilong administration can efficiently prevent epidemiological incidence of cardiac disease among SHS-exposed nonsmokers.

Attenuation of Magnesium Sulfate on CoCl2-Induced Cell Death by Activating ERK1/2/MAPK and Inhibiting HIF-1α via Mitochondrial Apoptotic Signaling Suppression in a Neuronal Cell Line.

Magnesium sulfate (MgSO4) ameliorates hypoxia/ischemia-induced neuronal apoptosis in a rat model. This study aimed to investigate the mechanisms governing the anti-apoptotic effect of MgSO4 on cobalt chloride (CoCl2)-exposed NB41A3 mouse neuroblastoma cells. MgSO4 increased the viability of NB41A3 cells treated with CoCl2 in a dose-dependent manner. MgSO4 treatment was shown to lead to an increase in the anti-apoptotic Bcl-2 family proteins, with a concomitant decrease in the pro-apoptotic proteins. MgSO4 also attenuated the CoCl2-induced disruption of mitochondrial membrane potential (ΔΨ(m)) and reduced the release of cytochrome c form the mitochondria to the cytosol. Furthermore, exposure to CoCl2 caused activation of the hypoxia-inducible factor 1α (HIF-1α). On the other hand, MgSO4 markedly reduced CoCl2-induced HIF-1α activation and suppressed HIF-1α downstream protein BNIP3. MgSO4 treatment induced ERK1/2 activation and attenuated CoCl2-induced activation of p38 and JNK. Addition of the ERK1/2 inhibitor U0126 significantly reduced the ability of MgSO4 to protect neurons from CoCl2-induced mitochondrial apoptotic events. However, incubation of cultures with the p38 and JNK inhibitors did not significantly affect MgSO4-mediated neuroprotection. MgSO4 appears to suppress CoCl2-induced NB41A3 cell death by activating ERK1/2/ MAPK pathways, which further modulates the role of Bcl-2 family proteins and mitochondria in NB41A3 cells. Our data suggest that MgSO4 may act as a survival factor that preserves mitochondrial integrity and inhibits apoptotic pathways.

Endothelin-1 enhances cell migration through COX-2 up-regulation in human chondrosarcoma.

BACKGROUND: Chondrosarcoma is a type of highly malignant tumor with a potent capacity of local invasion and distant metastasis. The effect of endothelin-1 (ET-1) on migration activity in human chondrosarcoma cells is not clearly understood. Here, we found that ET-1 increased the migration and expression of cyclooxygenase (COX)-2 in human chondrosarcoma cells. METHODS: ET-1-mediated COX-2 expression was assessed by qPCR and Western blot analysis. The mechanisms of action of ET-1 in different signaling pathways were studied using Western blotting. Knockdown of proteins was achieved by transfection with siRNA. Chromatin immunoprecipitation assays were used to study in vivo binding of c-Jun to the COX-2 promoter. RESULTS: Human chondrosarcoma tissues had significant expression levels of ET-1 and COX-2, which were higher than that in normal cartilage. Exogenous ET-1 increased cell migration and the expression of COX-2. In addition, COX-2 protein levels and cell migration ability were abolished by ET receptor antagonists. Activation of the mitogen-activated protein kinase (MAPK) and activator protein-1 (AP-1) pathways after ET-1 treatment was demonstrated, and ET-1-induced COX-2 expression and cell migration activity were inhibited by the specific inhibitor and mutant of MAPK and AP-1 cascades. ET-1 increased the binding of c-Jun to the AP-1 element on the COX-2 promoter. Furthermore, knockdown of ET-1 decreased cell metastasis in vitro and in vivo. CONCLUSIONS: Our results indicated that ET-1 enhances the cell migration of chondrosarcoma by increasing COX-2 expression through the ET receptors, MAPK, and AP-1 signal transduction pathway. GENERAL SIGNIFICANCE: We link high ET-1 and COX-2 expression to chondrosarcoma.

Gelsolin (GSN) induces cardiomyocyte hypertrophy and BNP expression via p38 signaling and GATA-4 transcriptional factor activation.

Cardiomyocyte hypertrophy is an adaptive response of the heart to various types of stress. During the period of stress accumulation, the transition from physiological hypertrophy to pathological hypertrophy results in the promotion of heart failure. Gelsolin (GSN) is a member of the actin-binding proteins, which regulate dynamic actin filament organization by severing and capping. Moreover, GSN also regulates cell morphology, differentiation, movement, and apoptosis. In this study, we used H9c2 and H9c2-GSN stable clones in an attempt to understand the mechanisms of GSN overexpression in cardiomyocytes. These data showed that the overexpression of GSN in H9c2-induced cardiac hypertrophy and increased the pathological hypertrophy markers atrial natriuretic peptide brain natriuretic peptide. Furthermore, we found that E-cadherin expression decreased with the overexpression of GSN in H9c2, but ß-catenin expression increased. These data presume that the cytoskeleton is loose. Further, previous studies show that the mitogen-activated protein kinase pathway can induce cardiac hypertrophy. Our data showed that p-p38 expression increased with the overexpression of GSN in H9c2, and the transcription factor p-GATA4 expression also increased, suggesting that the overexpression of GSN in H9c2-induced cardiac hypertrophy seemed to be regulated by the p38/GATA4 pathway. Moreover, we used both the p38 inhibitor (SB203580) and GSN siRNA to confirm our conjecture. We found that both of these factors significantly suppressed gelsolin-induced cardiac hypertrophy through p38/GATA4 signaling pathway. Therefore, we predict that the gene silencing of GSN and/or the downstream blocking of GSN along the p38 pathway could be applied to ameliorate pathological cardiac hypertrophy in the future.

Oral Lactobacillus reuteri GMN-32 treatment reduces blood glucose concentrations and promotes cardiac function in rats with streptozotocin-induced diabetes mellitus.

Impaired regulation of blood glucose levels in diabetes mellitus (DM) patients and the associated elevation of blood glucose levels are known to increase the risk of diabetic cardiomyopathy (DC). In the present study, a probiotic bacterium, Lactobacillus reuteri GMN-32, was evaluated for its potential to reduce blood glucose levels and to provide protection against DC risks in streptozotocin (STZ)-induced DM rats. The blood glucose levels of the STZ-induced DM rats when treated with L. reuteri GMN-32 decreased from 4480 to 3620 mg/l (with 107 colony-forming units (cfu)/d) and 3040 mg/l (with 109 cfu/d). Probiotic treatment also reduced the changes in the heart caused by the effects of DM. Furthermore, the Fas/Fas-associated protein with death domain pathway-induced caspase 8-mediated apoptosis that was observed in the cardiomyocytes of the STZ-induced DM rats was also found to be controlled in the probiotic-treated rats. The results highlight that L. reuteri GMN-32 treatment reduces blood glucose levels, inhibits caspase 8-mediated apoptosis and promotes cardiac function in DM rats as observed from their ejection fraction and fractional shortening values. In conclusion, the administration of L. reuteri GMN-32 probiotics can regulate blood glucose levels, protect cardiomyocytes and prevent DC in DM rats.

Reduction of TLR4 mRNA stability and protein expressions through inhibiting cytoplasmic translocation of HuR transcription factor by E2 and/or ERα in LPS-treated H9c2 cardiomyoblast cells.

Our previous results have indicated that Akt mediates 17ß-estradiol (E2) and/or estrogen receptor α (ERα) to inhibit lipopolysaccharide (LPS)-induced JNK activity, tumor necrosis factor α (TNFα) protein expression, and exhibits cardioprotective effects. Toll-like receptor 4 (TLR4) mRNAs often contain AU-rich elements (AREs) in their 3'-untranslated regions (3'UTR) which have a high affinity for RNA-binding proteins. It is not known whether E2 and ERα affect TLR4 mRNA stability and TLR4 protein expression through regulating the RNA-binding proteins, human antigen R (HuR), tristetraprolin (TTP) and AU-binding factor 1 (AUF-1) in myocardial cells. Therefore, we investigated if the LPS in- duces these RNA-binding proteins to regulate TLR4 mRNAs of cardiomyocytes, and whether the E2/ERα reduces the TLR4 mRNA stability induced by LPS through the inhibition of RNA-binding protein expression. Using a doxycycline (Dox)-induced Tet-On ERα H9c2 myocardic cell model, we also aimed to identify whether E2 and/or ERα regulate LPS-induced TLR4 mRNA stability. The results of Western blotting and reverse transcription-PCR assays demonstrated that LPS significantly in- creased the level of cytoplasmic HuR protein and the stability of TLR4 mRNA, and farther induced TLR4 protein expression in H9c2 cells, an effect mediated through the JNK pathway. Interestingly, E2 and/or ERα decreased the cytoplasmic HuR protein level and TLR4 mRNA stability, and farther decreased the level of TLR4 protein induced by LPS in H9c2 cardiomyoblast cells. Therefore, LPS triggered HuR expression which led to enhanced TLR4 mRNA and upregulated TLR4 expression through JNK1/2 in myocardial cells.

Herbal supplement attenuation of cardiac fibrosis in rats with CCl4-induced liver cirrhosis.

Previously we found carbon tetrachloride (CCl4) induced cirrhosis associated cardiac hypertrophy and apoptosis. The purpose of this study is to determine whether further CCl4 treatment would induce cardiac cell fibrosis. The cardiac tissues were analyzed by H&E. histological staining, Trichrome Masson staining and Western blotting. The results showed that the CCl4-treated-only group exhibits more trichrome staining, meaning that more fibrosis is present. Moreover, CCl4 could further induce cardiac-fibrosis via TGF-ß-p-Smad2/3-CTGF pathway. However, our data showed that the CCl4- indcued cardiac abnormalities were attenuated by Ocimum gratissimum extract (OGE) and silymarin co- treatments. In conclusion, our results indicated that the OGE and silymarin may be a potential traditional herb for the protection of cardiac tissues from the CCl4 induced cirrhosis associated cardiac fibrosis through modulating the TGF-ß signaling pathway.

Induction of apoptosis in human DU145 prostate cancer cells by KHC-4 treatment.

Prostate cancer (CaP) is one of the most prevalent cancers worldwide and the incidence and mortality rates have been rapidly increasing in recent years in Taiwan. Therefore, it is important to development anti-cancer therapy. In this study, KHC-4 was identified from 2-phenyl-4-quionolone derivatives in human prostate cancer cells and as a potential antitumor agent. In this study, we have identified KHC-4 induced apoptosis effects in castration-resistant prostate cancer DU145 cells, and the IC50 value of KHC-4 was 0.1 µM. KHC-4 suppressed the survival signaling p-PI3K and p-Akt and protein levels of Bcl-2 and Bcl-xL, upregulated Bax, cytochrome c and Caspase 8/9 and induced apoptosis by mitochondrial-dependent pathway. In JC-1 assay monitored the loss of membrane potential in KHC-4 treatments. TUNEL assay results showed DNA fragmentation in KHC-4 induced apoptosis. We concluded that KHC-4 exerted anti-tumor effects in DU145 cells by induction of apoptosis.

SHSST cyclodextrin complex prevents the fibrosis effect on CCl4-induced cirrhotic cardiomyopathy in rats through TGF-ß pathway inhibition effects.

Patients with liver cirrhosis also have subtle cardiac structure or function abnormalities. This cardiac dysfunction commonly occurs in 56% of waiting orthotopic liver transplantation (OLT) patients and is defined as cirrhotic cardiomyopathy (CCM). Up to now, there is no standard treatment because CCM does not have a solidly established diagnosis and is based on high clinical suspicion. The liver function of CCM is particularly limited, making patients vulnerable to more drug treatments. Here, we use silymarin (100 mg/kg/day), baicalein (30 mg/kg/day), San Huang Shel Shin Tang (SHSST, 30 mg/kg/day) and ß-cyclodextrin modified SHSST (SHSSTc, 30 and 300 mg/kg/day) treatments for a CCl4-induced CCM rat model. The results show that silymarin, baicalein and SHSST treatments can only slightly reduce the collagen accumulation in CCM rat hearts. However, SHSSTc treatment protects the heart in CCM and significantly inhibits collagen acumination and the fibrosis regulating transforming growth factor-ß (TGF-ß) pathway expression. SHSSTc treatments further reduced the heart weight and the ratio between left ventricular weight (LVW) and tibia length (TL). This experimental data show that water solubility improved ß-cyclodextrin modified Chinese herbal medicine formula (SHSSTc) can provide an excellent heart protection effect through TGF-ß pathway inhibition.

Identification of novel genetic susceptibility loci for calcium-containing kidney stone disease by genome-wide association study and polygenic risk score in a Taiwanese population.

Approximately 80% of kidney stone diseases contain calcium. Inherited genetic factors are among the variables that influence the development of calcium-containing kidney stone diseases (CKSD). Previous genome-wide association studies (GWAS) on stone diseases have been reported worldwide; however, these are not focused on calcium-containing stones. We conducted a GWAS to identify germline genetic polymorphisms associated with CKSD in a Medical Center in Taiwan; hence, this study was based primarily on a hospital-based database. CKSD was diagnosed using the chart records. Patients infected with urea-splitting-microorganisms and those with at least two urinary pH value below 5.5 were excluded. None of the patients had cystic stones based on stone analysis. Those over 40 years of age with no history of CKSD and no microscopic hematuria on urinalysis were considered as controls. The DNA isolated from the blood of 14,934 patients (63.7% male and 36.3% female) with CKSD and 29,868 controls (10,830 men and 19,038 women) at a medical center was genotyped for approximately 714,457 single nucleotide polymorphisms (SNPs) with minor allele frequency of ≥ 0.05. We used PLINK 1.9 to calculate the polygenic risk score (PRS) to investigate the association between CKSD and controls. The accuracy of the PRS was verified by dividing it into the training and testing groups. The statistical analyses were calculated with the area under the curve (AUC) using IBM SPSS version 22. We identified 432 susceptibility loci that reached a genome-wide threshold of P < 1.0 × 10- 5. A total of 132 SNPs reached a threshold of P < 5 × 10- 8 using a stricter definition of significance on chromosomes 4, 13, 16, 17, and 18. At the top locus of our study, SNPs in DGKH, PDILT, BCAS3, and ABCG2 have been previously reported. RN7SKP27, HDAC4, PCDH15, AP003068.2, and NFATC1 were novel findings in this study. PRS was adjusted for sex and age, resulting in an AUC of 0.65. The number of patients in the top quartile of PRS was 1.39 folds in the risk of CKSD than patients in the bottom quartile. Our data identified the significance of GWAS for patients with CKSD in a hospital-based study. The PRS also had a high AUC for discriminating patients with CKSD from controls. A total of 132 SNP loci of SNPs significantly associated with the development of CKSD. This first survey, which focused on patients with CKSD, will provide novel insights specific to CKSD and its potential clinical biomarkers.

Lumbrokinase attenuates side-stream-smoke-induced apoptosis and autophagy in young hamster hippocampus: correlated with eNOS induction and NFκB/iNOS/COX-2 signaling suppression.

Recent studies have found that cigarette smoke is epidemiologically linked to an increased risk for impaired cognitive development in adolescents. This study evaluated the influence of side stream smoke (SSS) exposure on hippocampal apoptosis and of the lumbrokinase (LK) effects on SSS induced apoptosis in young hamster hippocampus. Twenty male hamsters at six weeks of age were randomly divided into control group, SSS group (exposed to tobacco cigarettes smoke at doses of 10 cigarettes for 30 min twice a day for 1 month), and SSS hamsters with LK treatment (1.2 mg/kg, ip) for twice a week for 1 month. TUNEL assay and Western blotting were performed. The TUNEL-positive apoptotic cells, as well as Fas-dependent activity and mitochondria-dependent apoptotic pathways, such as Fas, FADD, activated caspase-8, t-Bid, activated caspase-9, and activated caspase-3, were significantly increased in the SSS-exposed hippocampus compared to the control and highly attenuated in the LK treatment group. Additionally, SSS exposure significantly increased the autophagy marker proteins, Beclin-1, ATG7, and LC3-II levels, in the hippocampus compared to those in the control group and obviously attenuated after LK treatment. LK also reduced hippocampus injury by enhancing eNOS expression and remarkably inhibited the proinflammatory NFκB/iNOS/COX-2 signaling activity. We found that the detrimental effects of SSS on the hippocampus are truly mediated by cell apoptosis and autophagy. However, LK reduced the hippocampus apoptosis and autophagy related injuries induced by SSS in a widespread manner. We suggest that LK presents protective effects on hippocampus apoptosis and has therapeutic potential against abnormal hippocampal function.

RNA helicase A is a DNA-binding partner for EGFR-mediated transcriptional activation in the nucleus.

EGF induces the translocation of EGF receptor (EGFR) from the cell surface to the nucleus where EGFR activates gene transcription through its binding to an AT-rich sequence (ATRS) of the target gene promoter. However, how EGFR, without a DNA-binding domain, can bind to the gene promoter is unclear. In the present study, we show that RNA helicase A (RHA) is an important mediator for EGFR-induced gene transactivation. EGF stimulates the interaction of EGFR with RHA in the nucleus of cancer cells. The EGFR/RHA complex then associates with the target gene promoter through binding of RHA to the ATRS of the target gene promoter to activate its transcription. Knockdown of RHA expression in cancer cells abrogates the binding of EGFR to the target gene promoter, thereby reducing EGF/EGFR-induced gene expression. In addition, interruption of EGFR-RHA interaction decreases the EGFR-induced promoter activity. Consistently, we observed a positive correlation of the nuclear expression of EGFR, RHA, and cyclin D1 in human breast cancer samples. These results indicate that RHA is a DNA-binding partner for EGFR-mediated transcriptional activation in the nucleus.

Suppression of TLR-4-related inflammatory pathway and anti-fibrosis effects of probiotic-fermented purple sweet potato yogurt in hearts of spontaneously hypertensive rats.

Inflammation plays an important role in triggering fibrosis of cardiovascular disease and hypertension. Gamma-aminobutyric acid (GABA) has hypotensive effect; GABA concentration could be enhanced in milk fermented with lactic acid bacteria (LAB). This study evaluated the effect of probiotic-fermented purple sweet potato yogurt (PSPY) on the toll-like receptor 4 (TLR-4)-related inflammatory components, and on fibrosis in the heart of spontaneously hypertensive rat (SHR). TLR4-related pathway and fibrosis-associated proteins TGFbeta and FGF2 were significantly increased in SHR hearts, but were highly suppressed in 10% PSPY-fed rats. Microscopic examination with Masson trichrome staining of left ventricle further demonstrated that 10% and 100% PSPY both significantly reduced interstitial fibrosis in SHR hearts. These findings indicated that oral administration of 10% probiotic-fermented PSPY was strong enough to lower cardiac fibrosis in SHR rats through the suppression of TLR-4-related inflammatory pathway. Therefore, PSPY may be included in diets to help prevent cardiac fibrosis in patients with hypertension.