Inhibition of a novel Dickkopf-1-LDL receptor-related proteins 5 and 6 axis prevents diabetic cardiomyopathy in mice.

BACKGROUND AND AIMS: Anti-hypertensive agents are one of the most frequently used drugs worldwide. However, no blood pressure-lowering strategy is superior to placebo with respect to survival in diabetic hypertensive patients. Previous findings show that Wnt co-receptors LDL receptor-related proteins 5 and 6 (LRP5/6) can directly bind to several G protein-coupled receptors (GPCRs). Because angiotensin II type 1 receptor (AT1R) is the most important GPCR in regulating hypertension, this study examines the possible mechanistic association between LRP5/6 and their binding protein Dickkopf-1 (DKK1) and activation of the AT1R and further hypothesizes that the LRP5/6-GPCR interaction may affect hypertension and potentiate cardiac impairment in the setting of diabetes. METHODS: The roles of serum DKK1 and DKK1-LRP5/6 signalling in diabetic injuries were investigated in human and diabetic mice. RESULTS: Blood pressure up-regulation positively correlated with serum DKK1 elevations in humans. Notably, LRP5/6 physically and functionally interacted with AT1R. The loss of membrane LRP5/6 caused by injection of a recombinant DKK1 protein or conditional LRP5/6 deletions resulted in AT1R activation and hypertension, as well as ß-arrestin1 activation and cardiac impairment, possibly because of multiple GPCR alterations. Importantly, unlike commonly used anti-hypertensive agents, administration of the anti-DKK1 neutralizing antibody effectively prevented diabetic cardiac impairment in mice. CONCLUSIONS: These findings establish a novel DKK1-LRP5/6-GPCR pathway in inducing diabetic injuries and may resolve the long-standing conundrum as to why elevated blood DKK1 has deleterious effects. Thus, monitoring and therapeutic elimination of blood DKK1 may be a promising strategy to attenuate diabetic injuries.

Huoxin pill prevents acute myocardial ischaemia injury via inhibition of Wnt/ß-catenin signaling.

Myocardial infarction (MI) is one of the leading causes of death worldwide, and due to the widespread and irreversible damage caused, new therapeutic treatments are urgently needed in order to limit the degree of ischaemic damage following MI. Aberrant activation of Wnt/ß-catenin signalling pathway often occurs during cardiovascular diseases including MI, which results in excess production of reactive oxygen species (ROS) and further promotes myocardial dysfunction. Huoxin pill (HXP) is a Traditional Chinese Medicine formula that has been widely used in the treatment of coronary heart disease and angina; however, its mechanisms remain unclear. Here, we performed mouse models of MI and examined the effects and mechanisms of HXP in protecting against MI-induced ischaemic damage. Our study showed that administration with HXP robustly protected against MI-induced cardiac injuries, decreased infarct size and improved cardiac function. Moreover, HXP attenuated ischaemia-induced DNA damage occurrence in vivo and H2 O2 -induced DNA damage occurrence in vitro, via potent inhibition of adverse Wnt/ß-catenin signalling activation. Our study thus elucidated the role and mechanism of HXP in protecting against MI and oxidative stress-induced injuries and suggests new therapeutic strategies in ischaemic heart disease via inhibition of Wnt/ß-catenin signalling pathway.

Network pharmacology-based analysis in determining the mechanisms of Huoxin pill in protecting against myocardial infarction.

CONTEXT: Huoxin pill (HXP) is a commonly used TCM prescription for treatment of cardiovascular diseases. However, its mechanism in protecting against myocardial infarction (MI) remains unknown. OBJECTIVE: We performed a network pharmacology analysis to explore the bioactive ingredients, therapeutic effects, and mechanisms of HXP in protecting against MI. MATERIALS AND METHODS: HPLC was used to identify major bioactive compounds, and overlap with MI target genes were visualised. 10-Week old C57BL/6 mice were randomly assigned as: Sham-operated control, MI + Phosphate buffered saline (PBS), and MI + HXP (3 mg/mL and 9 mg/mL) treatment groups, received oral gavage administration once every two-days starting from 1-week prior to MI, and subsequently MI models were established for one-week before sacrifice. RESULTS: AKT1, VEGFA, TNF and RELA were identified as core target proteins among eighty-five candidate bioactive compounds identified in HXP with overlapping MI-related genes. HXP protection against MI was mainly via regulation of inflammatory pathways, notably TNF signalling pathway. Mouse models of MI and cardiac myoblasts demonstrated that HXP improved MI-induced injury via improving regulation of inflammatory response. DISCUSSION AND CONCLUSION: Stellasterol, deoxycholic acid, kaempferol, and quercetin are important active compounds contained in HXP with anti-inflammatory properties in the therapeutic treatment of MI. Due to the straightforward nature and effectiveness of taking oral HXP medications, our findings provide a theoretical basis for the clinical application of HXP in treating patients with angina or myocardial ischaemia. Future research into the combination of surgical procedures or medications that restore blood flow together with HXP as supportive medication would be worthwhile.

IGFBP-4 enhances VEGF-induced angiogenesis in a mouse model of myocardial infarction.

Vascular endothelial growth factor (VEGF) is a well-known angiogenic factor, however its ability in promoting therapeutic angiogenesis following myocardial infarction (MI) is limited. Here, we aimed to investigate whether dual treatment with insulin-like growth factor binding protein-4 (IGFBP-4), an agent that protects against early oxidative damage, can be effective in enhancing the therapeutic effect of VEGF following MI. Combined treatment with IGFBP-4 enhanced VEGF-induced angiogenesis and prevented cell damage via enhancing the expression of a key angiogenic factor angiopoietin-1. Dual treatment with the two agents synergistically decreased cardiac fibrosis markers collagen-I and collagen-III following MI. Importantly, while the protective action of IGFBP-4 occurs at an early stage of ischemic injury, the action of VEGF occurs at a later stage, at the onset angiogenesis. Our findings demonstrate that VEGF treatment alone is often not enough to protect against oxidative stress and promote post-ischemic angiogenesis, whereas the combined treatment with IGFBP4 and VEGF can utilize the dual roles of these agents to effectively protect against ischemic and oxidative injury, and promote angiogenesis. These findings provide important insights into the roles of these agents in the clinical setting, and suggest new strategies in the treatment of ischemic heart disease.

Deletion of low-density lipoprotein-related receptor 5 inhibits liver Cancer cell proliferation via destabilizing Nucleoporin 37.

BACKGROUND: LRP5/6 are co-receptors in Wnt/ß-catenin pathway. Recently, we discovered multiple ß-catenin independent functions of LRP5/6 in tumor cells and in the diseased heart. Nucleoporin 37 (NUP37) is an important component of the nuclear pore complex (NPC), whose elevated expression is associated with worsened prognosis in liver cancer. Previous studies have shown that NUP37 interacted with YAP and activated YAP/TEAD signaling in liver cancer. Our preliminary findings showed a nuclear location of LRP5. We thus tested the hypothesis that LRP5 may act as a genuine regulator of YAP/TEAD signaling via modulating NUP37 in a ß-catenin-independent way. METHODS: We performed siRNA knockdown of LRP5, LRP6, or ß-catenin in liver cancer HepG2 cells to determine the effect on tumor cell proliferation. Protein expressions and interaction between LRP5 and NUP37 were determined using immunoprecipitation and western blot analyses. RESULTS: HepG2 cell proliferation was markedly inhibited by knockdown of LRP5 but not LRP6 or ß-catenin, suggesting that LRP5 has a specific, ß-catenin-independent role in inhibiting HepG2 cell proliferation. Knockdown of NUP37 by siRNA inhibited the proliferation of HepG2 cells, whereas overexpression of NUP37 reversed the decrease in cell proliferation induced by LRP5 knockdown. Immunoprecipitation assays confirmed that LRP5 bound to NUP37. Furthermore, LRP5 overexpression restored NUP37 knockdown-induced downregulation of YAP/TEAD pathway. CONCLUSIONS: LRP5 deletion attenuates cell proliferation via destabilization of NUP37, in a ß-catenin-independent manner. LRP5 therefore acts as a genuine regulator of YAP/TEAD signaling via maintaining the integrity of the NPC, and implicates a therapeutic strategy in targeting LRP5 for inhibiting liver cancer cell proliferation.

Opposing Roles of Wnt Inhibitors IGFBP-4 and Dkk1 in Cardiac Ischemia by Differential Targeting of LRP5/6 and ß-catenin.

BACKGROUND: Myocardial infarction is one of the leading causes of morbidity and mortality worldwide, triggering irreversible myocardial cell damage and heart failure. The role of low-density lipoprotein receptor-related proteins 5 and 6 (LRP5/6) as coreceptors of the Wnt/ß-catenin pathway in the adult heart remain unknown. Insulin-like growth factor binding protein 4 and dickkopf-related protein 1 (Dkk1) are 2 secreted LRP5/6 binding proteins that play a crucial role in heart development through preventing Wnt/ß-catenin pathway activation. However, their roles in the adult heart remain unexplored. METHODS: To understand the role of LRP5/6 and ß-catenin in the adult heart, we constructed conditional cardiomyocyte-specific LRP5/6 and ß-catenin knockout mice and induced surgical myocardial infarction. We also directly injected recombinant proteins of insulin-like growth factor binding protein 4 and Dkk1 into the heart immediately following myocardial infarction to further examine the mechanisms through which these proteins regulate LRP5/6 and ß-catenin. RESULTS: Deletion of LRP5/6 promoted cardiac ischemic insults. Conversely, deficiency of ß-catenin, a downstream target of LRP5/6, was beneficial in ischemic injury. It is interesting to note that although both insulin-like growth factor binding protein 4 and Dkk1 are secreted Wnt/ß-catenin pathway inhibitors, insulin-like growth factor binding protein 4 protected the ischemic heart by inhibiting ß-catenin, whereas Dkk1 enhanced the injury response mainly through inducing LRP5/6 endocytosis and degradation. CONCLUSIONS: Our findings reveal previously unidentified dual roles of LRP5/6 involved in the cardiomyocyte response to ischemic injury. These findings suggest new therapeutic strategies in ischemic heart disease by fine-tuning LRP5/6 and ß-catenin signaling within the Wnt/ß-catenin pathway.

Supply chain carbon footprinting and responsibility allocation under emission regulations.

Reduction of greenhouse gas emissions has become an enormous challenge for any single enterprise and its supply chain because of the increasing concern on global warming. This paper investigates carbon footprinting and responsibility allocation for supply chains involved in joint production. Our study is conducted from the perspective of a social planner who aims to achieve social value optimization. The carbon footprinting model is based on operational activities rather than on firms because joint production blurs the organizational boundaries of footprints. A general model is proposed for responsibility allocation among firms who seek to maximize individual profits. This study looks into ways for the decentralized supply chain to achieve centralized optimality of social value under two emission regulations. Given a balanced allocation for the entire supply chain, we examine the necessity of over-allocation to certain firms under specific situations and find opportunities for the firms to avoid over-allocation. The comparison of the two regulations reveals that setting an emission standard per unit of product will motivate firms to follow the standard and improve their emission efficiencies. Hence, a more efficient and promising policy is needed in contrast to existing regulations on total production.

Overexpanded CAG repeats in ATN1 cause an Early-Onset Case of Dentatorubral-Pallidoluysian atrophy with novel phenotypes and a literature Review of Chinese patients.

OBJECTIVE: Dentatorubral-pallidoluysian atrophy (DRPLA) is an inherited neurodegenerative disease caused by CAG overexpansion (≥48 tandem copies) in ATN1. The aim of this research was to explore the genetic cause of a large Chinese DRPLA pedigree and to review the characteristics of Chinese DRPLA patients. METHODS: Suspected variants were screened by high-throughput sequencing. The number of CAG repeats was assessed by polymerase chain reaction using FAM-labeled primers followed by capillary electrophoresis. Literature on previously reported DRPLA cases with overexpanded ATN1 CAG repeats in China was reviewed. RESULTS: After contracting a lung infection, the proband suffered early-onset DRPLA symptoms and novel phenotypes, transitioning from insomnia to stupor. The numbers of CAG repeats in the proband, her grandfather, father, mother, brother, and aunt were 8/81, 17/54, 10/57, 8/10, 10/10, and 10/17, respectively. Possible incomplete penetrance was observed in this pedigree. CONCLUSION: We described a large Chinese DRPLA pedigree in which the proband carried the largest CAG expansion reported in China. We also reviewed the characteristics of Chinese DRPLA patients and broadened the phenotypic spectrum.

Species distribution modeling combined with environmental DNA analysis to explore distribution of invasive alien mosquitofish (Gambusia affinis) in China.

China has become one of the most serious countries suffering from biological invasions in the world. In the context of global climate change, invasive alien species (IAS) are likely to invade a wider area, posing greater ecological and economic threats in China. Western mosquitofish (Gambusia affinis), which is known as one of the 100 most invasive alien species, has distributed widely in southern China and is gradually spreading to the north, causing serious ecological damage and economic losses. However, its distribution in China is still unclear. Hence, there is an urgent need for a more convenient way to detect and monitor the distribution of G. affinis to put forward specific management. Therefore, we detected the distribution of G. affinis in China under current and future climate change by combing Maxent modeling prediction and eDNA verification, which is a more time-saving and reliable method to estimate the distribution of species. The Maxent modeling showed that G. affinis has a broad habitat suitability in China (especially in southern China) and would continue to spread in the future with ongoing climate change. However, eDNA monitoring showed that occurrences can already be detected in regions that Maxent still categorized as unsuitable. Besides temperature, precipitation and human influence were the most important environmental factors affecting the distribution of G. affinis in China. In addition, by environmental DNA analysis, we verified the presence of G. affinis predicted by Maxent in the Qinling Mountains where the presence of G. affinis had not been previously recorded.

Resveratrol prevents Ang II-induced cardiac hypertrophy by inhibition of NF-κB signaling.

BACKGROUND: Pathological cardiac hypertrophy is a hallmark of various cardiovascular diseases (CVD) including chronic heart failure (HF) and an important target for the treatment of these diseases. Aberrant activation of Angiotensin II (Ang II)/AT1R signaling pathway is one of the main triggers of cardiac hypertrophy, which further gives rise to excessive inflammation that is mediated by the key transcription factor NF-κB. Resveratrol (REV) is a natural polyphenol with multiple anti-inflammatory and anti-oxidative effects, however the ability of REV in preventing Ang II-induced cardiac hypertrophy in combination with NF-κB signaling activation remains unclear. METHODS: Murine models of cardiac hypertrophy was conducted via implantation of Ang II osmotic pumps. Primary neonatal rat cardiomyocyte and heart tissues were examined to determine the effect and underlying mechanism of REV in preventing Ang II-induced cardiac hypertrophy. RESULTS: Administrations of REV significantly prevented Ang II-induced cardiac hypertrophy, as well as robustly attenuated Ang II-induced cardiac fibrosis, and cardiac dysfunction. Furthermore, REV not only directly prevented Ang II/AT1R signal transductions, but also prevented Ang II-induced expressions of pro-inflammatory cytokines and activation of NF-κB signaling pathway. CONCLUSIONS: Our study provides important new mechanistic insight into the cardioprotective effects of REV in preventing Ang II-induced cardiac hypertrophy via inhibiting adverse NF-κB signaling activation. Our findings further suggest the therapeutic potential of REV as a promising drug for the treatment of cardiac hypertrophy and heart failure.

Babao Dan Alleviates Cancer Cachexia in Mice Via Inhibiting IL-6/STAT3 Signaling Pathway.

BACKGROUND: Cancer cachexia is a common but severe condition that causes muscle wasting, body weight loss, and progressive functional impairment, affecting over 50% of cancer patients. Currently, there are no effective treatments that can alleviate cachexia, and hence the discovery of new therapeutics that can effectively prevent or even reverse cancer cachexia is crucial. Babao Dan (BBD) is a Traditional Chinese Medicine (TCM) formula that has been used clinically in combating various cancers, however, its therapeutic potential in alleviating cancer cachexia remains unexplored. Our current study aims to determine the anti-cachectic effects of BBD treatment in alleviating cancer cachexia, as well as determining the underlying mechanisms involved. METHODS: Mouse models of cancer cachexia were induced via implantation of CT26 colon adenocarcinoma cells, and the anti-cachectic effects and mechanisms of BBD were determined via examinations of body weight and muscle mass, as well as serum and muscle markers of cachexia and muscle atrophy. RESULTS: CT26 tumor implantation reduced in the rapid occurrence of cancer cachexia characterized by marked reductions in body weight and muscle mass, functional decrease in muscle function and accelerated deaths. BBD administration not only demonstrated robust anti-cachectic ability via preventing decreases in body weight, muscle mass, and muscle atrophy, but also markedly prolonged survival. The effects of BBD in alleviating cancer cachexia and its associated adverse effects were due to its ability in preventing the activation of IL-6/STAT3 signaling post-CT26 tumor implantation. CONCLUSION: Our findings demonstrated the robust ability of BBD in preventing cancer cachexia and alleviating the main cachexia-induced symptoms as well as prolonging survival via inhibiting activation of IL-6/STAT3 signaling pathway. Therefore, our study demonstrating the strong anti-cachectic effects of BBD in mice may provide a theoretical basis for the use of BBD as a safe and effective drug in the treatment of cancer cachexia.

Qingda granule prevents obesity-induced hypertension and cardiac dysfunction by inhibiting adverse Akt signaling activation.

Obesity rates have rapidly increased worldwide and obesity-related diseases such as hypertension and cardiovascular diseases have become leading factors for global morbidity and mortality. Currently, there are no effective treatments that can prevent or reverse obesity long-term, and hence the prevention of obesity-related adverse effects such as hypertension is critical. Qingda granule (QDG) is a condensed Traditional Chinese Medicine (TCM) formula that has been used clinically for treating hypertension, however, its effectiveness in obesity-induced hypertension and cardiac dysfunction remains explored. Mouse models of obesity via long-term feeding of high-fat high-fructose diet (HFFD) were established to examine the effect and mechanism of QDG in protecting against obesity-induced hypertension and cardiac dysfunction. C57BL/6 mice were fed with either normal diet or HFFD over a period of 16 weeks and administered with either saline or QDG for assessment of obesity-induced blood pressure and cardiac function. QDG administration demonstrated robust anti-hypertensive effects and significantly attenuated HFFD-induced elevations in blood pressures. Moreover, QDG treatment also demonstrated robust cardioprotective effects during obesity-induced hypertension by markedly improving cardiac function and preventing cardiac hypertrophy. QDG protected against obesity-induced hypertension and cardiac dysfunction was due to its ability to prevent adverse chronic activation of Akt signaling pathway during long-term feeding of HFFD. Long-term usage of QDG treatments exhibited no observable side effects and also completely prevented obesity-induced organ damage, demonstrating the feasibility and safety of prolonged use. Our findings thus elucidated the role of QDG in preventing obesity-induced hypertension and cardiac hypertrophy via inhibiting adverse activation of Akt signaling activation. Therefore, our study provides the theoretical basis for the utilization of QDG as both a safe and effective drug in the therapeutic treatment of metabolic diseases such as obesity-induced hypertension.

Huoxin pill prevents excessive inflammation and cardiac dysfunction following myocardial infarction by inhibiting adverse Wnt/ß­catenin signaling activation.

BACKGROUND: Myocardial infarction (MI) is the most common cause of cardiac injury, resulting in widespread and irreversible damage to the heart. The incidence of MI gives rise to the excessive production of inflammatory cytokines that further promotes myocardial dysfunction. Wnt/ß-catenin signaling pathway is adversely activated during MI and plays an important role in the modulation of the inflammatory response following tissue injury. Huoxin pill (HXP) is a Traditional Chinese Medicine formulation that has been long used in the treatment of cardiovascular diseases, however its mechanisms of cardioprotection remain unclear. METHODS: We performed murine models of MI in order to model myocardial ischemic damage and examine the effect and underlying mechanism of HXP in protecting against myocardial ischemic injury. We further constructed conditional cardiomyocyte-specific ß-catenin knockout mice and induced surgical MI in order to better understand the role of Wnt/ß-catenin signaling following myocardial infarction in the adult heart. RESULTS: HXP administration strongly protected against cardiac ischemic injury, improved cardiac function, and markedly decreased the expression of pro-inflammatory cytokines following MI. Nuclear activation of ß­catenin resulted in significantly increased nuclear translocation and activation of NF-κB. In contrast, cardiomyocyte-specific deletion of ß-catenin decreased NF-κB activation and exhibited beneficial effects following ischemic injury. Hence, HXP protected against MI-induced ischemic injury and excessive inflammatory response via inhibiting Wnt/ß­catenin signaling. CONCLUSIONS: Our study elucidated the role of HXP in protecting against ischemic myocardial injury via preventing MI-induced inflammatory response, which was mediated by its ability to inhibit adverse Wnt/ß­catenin signaling activation. Thus, our study provides the basis for the implementation of HXP as an effective therapeutic strategy in protecting against myocardial ischemic diseases.

Babao Dan is a robust anti-tumor agent via inhibiting wnt/ß-catenin activation and cancer cell stemness.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese Medicine (TCM) is being increasingly used worldwide due to its diverse efficacy and relatively low side effects. Babao Dan (BBD) is a well-known TCM formula that is currently used for the effective treatment of various cancers, however its underlying molecular mechanism remains unknown. AIM OF THE STUDY: Tumor growth and tumor recurrence are characterized by two distinct populations of cells, namely the well-differentiated cancer cells composing the majority of tumor bulk, and cancer stem cells (CSCs) involved in tumor relapse, which are both strongly associated with excessive activation of Wnt/ß-catenin signaling. Our study aims to elucidate the underlying molecular mechanisms associated with the anti-tumor proliferative effects of Babao Dan (BBD). MATERIALS AND METHODS: We used a hepatoblastoma cell line HepG2 with stem cell-like traits that harbors a constitutively active mutant of ß-catenin in order to study the anti-tumor ability of BBD via targeting Wnt/ß-catenin signaling. RESULTS: BBD robustly attenuated both the intrinsic and extrinsic activation of Wnt/ß-catenin pathway in HepG2 hepatoblastoma cells, as well as Wnt target genes. Moreover, BBD significantly inhibited both the proliferation of well-differentiated cancer cells, as well as the stem-like property of CSCs as evidenced by EpCAM, a Wnt target gene and a novel marker of cancer cell stemness. In addition, mice administered with BBD using HepG2 cell line derived xenograft model had marked reductions in tumor size and weight, as well as significantly decreased expressions of Wnt target genes and cancer cell stemness. CONCLUSION: Our findings elucidated the underlying molecular mechanisms associated with the robust anti-tumor effects of BBD via potent inhibition of Wnt/ß-catenin signaling, and implicate its use in the clinical treatment of cancers.

Primary anaplastic large cell lymphoma of the central nervous system in a child: A case report.

INTRODUCTION: To report the clinical characteristics of primary central nervous system T-cell lymphoma with anaplastic lymphoma kinase-1 (ALK-1) positive in an 8-year-old male. PATIENT CONCERNS: The patient presented cognitive impairment, dizziness, vomiting, fever, and convulsions during the disease, followed by progressive and persistent severe headache, progressive increase of intracranial pressure, indifference, disorder of consciousness, mild increase in white blood cells in cerebrospinal fluid, progressive decrease of sugar, progressive increase of protein, abnormal signal of left parietal-occipital, local meningeal enhancement, and cerebrospinal fluid cytology. DIAGNOSIS: He was diagnosed with ALK-1-positive central nervous system T-cell lymphoma. INTERVENTIONS: Meropenem and vancomycin were administered to counter the infection, while dexamethasone alleviated the inflammation. OUTCOMES: The patient died of cerebral hernia due to intracranial hypertension in the eighth week of the disease. CONCLUSIONS: PCNS ALK-1-positive anaplastic large cell lymphoma is extremely rare. Also, it is difficult to distinguish from central meningeal lymphoma and central nervous system infection, which might lead to delayed diagnosis. However, early diagnosis depends on the pathological diagnosis of brain tissue biopsy.

LRP6 Ectodomain Prevents SDF-1/CXCR4-Induced Breast Cancer Metastasis to Lung.

PURPOSE: Lung metastasis is an important cause of breast cancer-related deaths, in which SDF-1/CXCR4 signaling pathway plays a critical role. Single transmembrane protein LRP6 is viewed as an oncogene via activating the Wnt/ß-catenin signaling pathway. Our work aims to investigate the relationship between SDF-1/CXCR4 and LRP6 in breast cancer lung metastasis. EXPERIMENTAL DESIGN: We examined the expressions and functions of SDF-1/CXCR4 and LRP6 as well as their relationship in breast cancer in vitro and in vivo. RESULTS: LRP6 ectodomain (LRP6N) directly bound to CXCR4 and competitively prevented SDF-1 binding to CXCR4. LRP6N prevented SDF-1/CXCR4-induced metastasis to lung and prolonged survival in mice bearing breast tumors, whereas LRP6 knockdown activated SDF-1/CXCR4 signal transduction and promoted lung metastasis and tumor death. Furthermore, patients with breast cancer with high CXCR4 expression had poor prognosis, which was exacerbated by low LRP6 expression but improved by high LRP6 expression. Interestingly, a secreted LRP6N was found in the serum of mice and humans, which was downregulated by the onset of cancer metastasis in both mice bearing breast cancer as well as in patients with breast cancer. CONCLUSIONS: LRP6N might be a promising diagnostic marker for the early detection of breast cancer metastasis as well as an inhibitor of SDF-1/CXCR4-induced breast cancer metastasis. LRP6N also provides an interesting link between Wnt signaling and SDF-1/CXCR4 signaling, the two key pathways involved in cancer development.

Risk factors and associated complications for postoperative urinary retention after lumbar surgery for lumbar spinal stenosis.

BACKGROUND CONTEXT: Postoperative urinary retention (POUR) is a very common postoperative complication of all surgeries (5%-70%) that may lead to complications such as urinary tract infection (UTI), bladder overdistension, autonomic dysregulation, and increased postoperative length of stay (LOS). Within the field of spine surgery, the reported incidence rate of POUR is highly variable (5.6%-38%). Lack of clear stratification of surgical level, spinal pathology, and inadequate sample size are major limitations of available studies concerning POUR following spine surgery, which may lead to inconsistency in the incidence of POUR and the ability to model its occurrence and consequences. PURPOSE: This study examines the incidence, predictive factors, and complications of POUR in patients undergoing elective posterior lumbar decompression with or without fusion for lumbar stenosis to eliminate bias from studying procedures done in different anatomical regions and with different approaches. Additionally, this study intends to identify the consequences of POUR. STUDY DESIGN AND SETTING: A retrospective consecutive cohort analysis was performed to examine patients undergoing posterior lumbar decompression who did and did not develop POUR. PATIENT SAMPLE: All patients undergoing posterior lumbar decompression with or without fusion for lumbar stenosis with claudication from January 2014 through December 2015 at our institution were evaluated. Patients under the age of 18 and patients with spinal malignancies or infections were excluded. OUTCOME MEASURES: Physiological measures included identification of POUR by evidence of reinsertion of a Foley catheter, use of straight catheterization postoperatively, or by a clear medical diagnosis with pharmacologic treatment. Other physiological measures included identification of development of UTI, sepsis, acute kidney injury (AKI), surgical site infection (SSI), or readmission within 90 days after surgery, as well as LOS and discharge disposition. METHODS: The electronic medical record was searched for all patients meeting inclusion and exclusion criteria. Postoperative urinary retention was defined as reinsertion of a Foley catheter, use of straight catheterization postoperatively, or a clear medical diagnosis with pharmacologic treatment. Statistical analysis was performed in R statistical software package version 3.3.2. Multiple variable selection techniques were used to determine appropriate variables for regression models, and logistic models were fit to the development of POUR and postoperative complications, whereas a linear regression model was used for LOS. RESULTS: Data were collected on 1,592 consecutive patients. Among the sample population, the mean age at surgery was 67 (standard deviation 10.1) and 45% of patients were women. The incidence rate of POUR was 17.1% (273/1592). Increased age (odds ratio [OR]=1.04; 95% confidence interval [CI], 1.02-1.06; p<.001), benign prostatic hyperplasia (BPH) (OR=1.92; 95% CI, 1.32-2.78); p<.001), previous AKI (OR=3.29; 95% CI, 1.11-9.29; p=.025), and previous UTI (OR=1.69; 95% CI, 1.24-2.24; p<.001) significantly increased the probability of developing POUR. Factors including increased body mass index, coronary artery disease, congestive heart failure, diabetes mellitus, chronic obstructive pulmonary disease, tobacco use, and fusion were found to be non-significant and were excluded from the model. With respect to complications, POUR was found to be associated with development of UTI (OR=4.50; 95% CI, 3.14-6.45; p<.001), sepsis (OR=4.05; 95% CI, 1.16-13.55; p=.022), increased LOS (p<.001), increased likelihood to be discharged to a skilled nursing facility (SNF) (OR of discharge to home=0.44; 95% CI, 0.32-0.62; p<.001), and increased risk of readmission within 90 days of the index surgery (OR=1.60; 95% CI, 1.11-2.26; p=.009). Development of POUR did not increase the risk of developing AKI (OR=2.45; 95% CI, 0.93-6.30; p=.063) or a SSI (OR=1.09; 95% CI, 0.56-2.02; p=.79). CONCLUSIONS: Overall, POUR was a significant risk factor for the development of UTI, sepsis, increased LOS, discharge to a SNF, and readmission within 90 days. Surgeons and anesthesiologists should take preventative measures against POUR in individuals with increased age, BPH, AKI, and UTI within 90 days before surgery, as these factors were found to significantly increase the risk of POUR.

Baicalin alleviates H2O2­induced injury of H9c2 cardiomyocytes through suppression of the Wnt/ß­catenin signaling pathway.

Baicalin is one of the active ingredients extracted from the dry root of Scutellaria baicalensis Georgi, which has been reported to be effective in preventing myocardial ischemia reperfusion injury. However, the mechanisms underlying its cardioprotective activities remain to be elucidated. In the present study, H2O2­treated cardiomyocyte H9c2 cell line served as an in vitro model of oxidation­damaged cardiomyocytes to evaluate the effects of baicalin on the cardiac injury, and to investigate the underlying molecular mechanism. The results of the TOPFlash/Renilla reporter gene assay indicated that baicalin significantly suppressed the activation of proto­oncogene Wnt­1 (Wnt)/ß­catenin in 293 cells, in a dose dependent manner. In addition, baicalin significantly inhibited H2O2­induced loss of H9c2 cell viability in MTT assay. Furthermore, western blotting analysis demonstrated that baicalin markedly attenuated H2O2­induced cell apoptosis, as demonstrated by the down­regulation of cleaved caspase­3 and the increase in the apoptosis regulator Bcl­2 (Bcl­2)/apoptosis regulator BAX (Bax) ratio following baicalin treatment in H2O2­treated H9c2 cells. Furthermore, baicalin markedly decreased the expression of ß­catenin and downstream Axin­2 and myc proto­oncogene protein in H2O2­treated H9c2 cells. Knockdown of ß­catenin expression inhibited H2O2­induced cell apoptosis. Finally, LiCl (a ß­catenin stabilizer) induced apoptosis of H9c2 cells by upregulating the expression of ß­catenin, which was significantly neutralized by the treatment with baicalin. Taken together, it is hypothesized that baicalin exerts cardioprotective effects via suppression of the Wnt/ß­catenin signaling pathway.

LRP5/6 directly bind to Frizzled and prevent Frizzled-regulated tumour metastasis.

How Wnt signalling including canonical and non-canonical pathways are initiated at the cell surface is not completely understood. Here we report that Wnt receptor Frizzled (Frz) and theco-receptors LRP5 and LRP6 (LRP5/6) directly interact with each other and this interaction is regulated by the LRP6 ectodomain. Importantly, through direct binding to Frz, LRP5/6 are able to prevent Frz-regulated non-canonical pathway activation and further non-canonical pathway-mediated tumour metastasis. Knockdown of endogenous LRP5/6 promotes otherwise-nonaggressive tumour cells to migrate in vitro, whereas a soluble recombinant protein of LRP6 ectodomain suppresses migration and metastasis of otherwise-aggressive tumour cells in vitro and in vivo. Furthermore, the expression level of membrane LRP5/6 correlates inversely with metastasis in mouse and human breast cancer. Our study suggests a previously unrecognized mode of receptor interaction, revealing the mechanism of LRP5/6 in inhibition of non-canonical pathway, and a possible clinical use of the LRP6 ectodomain to impede metastasis.

LRP6 dimerization through its LDLR domain is required for robust canonical Wnt pathway activation.

Canonical Wnt/ß-catenin signaling pathway plays important roles in multiple aspects of cellular responses in development and diseases. It is currently thought that Wnt receptor Frizzled (Frz) exists separately to Wnt coreceptors LRP5 and LRP6 (LRP5/6), and that Wnt-Frz-LRP5/6 triple complex formation bridged by Wnt ligand is needed for canonical pathway activation. We recently showed that Frz and LRP5/6 interact with each other in the absence of Wnt ligand binding and this interaction maintains the Frz-LRP5/6 complex in an inactive state. Here, we further show that Wnt ligand stimulation induces conformational change of the Frz-LRP6 complex and leads to hexamer formation containing the core LDLR domain-mediated LRP6 homodimer that is stabilized by two pairs of Wnt3a and Frz8, that is, Wnt3a-Frz8-LRP6-LRP6-Frz8-Wnt3a. This LDLR-mediated LRP6 dimerization is essential for robust canonical Wnt pathway activation. Our study thus suggests a previously unrecognized mode of receptor interaction in Wnt signal initiation.