Angiotensin II upregulates endothelial lipase expression via the NF-kappa B and MAPK signaling pathways

Blocking H1R signal aggravates atherosclerosis by promoting inflammation and foam cell formation

Atherosclerosis (AS) is a chronic inflammatory arterial disease, in which abnormal lipid metabolism and foam cell formation play key roles. Histamine is a vital biogenic amine catalyzed by histidine decarboxylase (HDC) from L-histidine. Histamine H1 receptor (H1R) antagonist is a commonly encountered anti-allergic agent in the clinic. However, the role and mechanism of H1R in atherosclerosis have not been fully elucidated. Here, we explored the effect of H1R on atherosclerosis using Apolipoprotein E-knockout (ApoE-/-) mice with astemizole (AST, a long-acting H1R antagonist) treatment. The results showed that AST increased atherosclerotic plaque area and hepatic lipid accumulation in mice. The result of microarray study identified a significant change of endothelial lipase (LIPG) in CD11b+ myeloid cells derived from HDC-knockout (HDC-/-) mice compared to WT mice. Blocking H1R promoted the formation of foam cells from bone marrow-derived macrophages (BMDMs) of mice by up-regulating p38 mitogen-activated protein kinase (p38 MAPK) and LIPG signaling pathway. Taken together, these findings demonstrate that blocking H1R signal aggravates atherosclerosis by promoting abnormal lipid metabolism and macrophage-derived foam cell formation via p38 MAPK-LIPG signaling pathway. KEY MESSAGES: Blocking H1R signal with AST aggravated atherosclerosis and increased hepatic lipid accumulation in high-fat diet (HFD)-fed ApoE-/- mice. Blocking H1R signal promoted macrophage-derived foam cell formation via p38 MAPK-LIPG signaling pathway.

Developmental Impacts of Epigenetics and Metabolism in COVID-19

Developmental biology is intricately regulated by epigenetics and metabolism but the mechanisms are not completely understood. The situation becomes even more complicated during diseases where all three phenomena are dysregulated. A salient example is COVID-19, where the death toll exceeded 6.96 million in 4 years, while the virus continues to mutate into different variants and infect people. Early evidence during the pandemic showed that the host's immune and inflammatory responses to COVID-19 (like the cytokine storm) impacted the host's metabolism, causing damage to the host's organs and overall physiology. The involvement of angiotensin-converting enzyme 2 (ACE2), the pivotal host receptor for the SARS-CoV-2 virus, was identified and linked to epigenetic abnormalities along with other contributing factors. Recently, studies have revealed stronger connections between epigenetics and metabolism in COVID-19 that impact development and accelerate aging. Patients manifest systemic toxicity, immune dysfunction and multi-organ failure. Single-cell multiomics and other state-of-the-art high-throughput studies are only just beginning to demonstrate the extent of dysregulation and damage. As epigenetics and metabolism directly impact development, there is a crucial need for research implementing cutting-edge technology, next-generation sequencing, bioinformatics analysis, the identification of biomarkers and clinical trials to help with prevention and therapeutic interventions against similar threats in the future.

Vasculoprotective Potential of Baicalein in Angiotensin II-Infused Abdominal Aortic Aneurysms through Inhibiting Inflammation and Oxidative Stress

Aortic wall inflammation, abnormal oxidative stress and progressive degradation of extracellular matrix proteins are the main characteristics of abdominal aortic aneurysms (AAAs). The nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome dysregulation plays a crucial role in aortic damage and disease progression. The first aim of this study was to examine the effect of baicalein (5,6,7-trihydroxy-2-phenyl-4H-1-benzopyran-4-one) on AAA formation in apolipoprotein E-deficient (ApoE-/-) mice. The second aim was to define whether baicalein attenuates aberrant vascular smooth muscle cell (VSMC) proliferation and inflammation in VSMC culture. For male ApoE-/- mice, a clinically relevant AAA model was randomly divided into four groups: saline infusion, baicalein intraperitoneal injection, Angiotensin II (Ang II) infusion and Ang II + baicalein. Twenty-seven days of treatment with baicalein markedly decreased Ang II-infused AAA incidence and aortic diameter, reduced collagen-fiber formation, preserved elastic structure and density and prevented smooth muscle cell contractile protein degradation. Baicalein inhibited rat VSMC proliferation and migration following the stimulation of VSMC cultures with Ang II while blocking the Ang II-inducible cell cycle progression from G0/G1 to the S phase in the synchronized cells. Cal-520 AM staining showed that baicalein decreased cellular calcium in Ang II-induced VSMCs; furthermore, a Western blot assay indicated that baicalein inhibited the expression of PCNA and significantly lowered levels of phospho-Akt and phospho-ERK, along with an increase in baicalein concentration in Ang II-induced VSMCs. Immunofluorescence staining showed that baicalein pretreatment reduced NF-κB nuclear translocation in Ang II-induced VSMCs and furthered the protein expressions of NLRP3 while ASC and caspase-1 were suppressed in a dose-dependent manner. Baicalein pretreatment upregulated Nrf2/HO-1 signaling in Ang II-induced VSMCs. Thus, 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining showed that its reactive oxygen species (ROS) production decreased, along with the baicalein pretreatment. Our overall results indicate that baicalein could have therapeutic potential in preventing aneurysm development.

Genetic Polymorphisms of Ischemic Stroke in Asians

The increasing incidence of ischemic stroke emphasizes the necessity for early detection and preventive strategies. Diagnostic biomarkers currently available for ischemic stroke only become detectable shortly before the manifestation of stroke symptoms. Genetic variants associated with ischemic stroke offer a potential solution to address this diagnostic limitation. However, it is crucial to acknowledge that genetic variants cannot be modified in the same way as epigenetic changes. Nevertheless, individuals carrying risk or protective variants can modify their lifestyle to potentially influence the associated epigenetic factors. This study aims to summarize specific variants relevant to Asian populations that may aid in the early detection of ischemic stroke and explore their impact on the disease's pathophysiology. These variants give us important information about the genes that play a role in ischemic stroke by affecting things like atherosclerosis pathway, blood coagulation pathway, homocysteine metabolism, transporter function, transcription, and the activity of neurons regulation. It is important to recognize the variations in genetic variants among different ethnicities and avoid generalizing the pathogenesis of ischemic stroke.

Guanxinping ameliorates atherosclerosis via MAPK/NF-κB signaling pathway in ApoE-/- mice

BACKGROUND

Atherosclerosis (AS), one of the leading causes of deaths and disabilities, is a kind of vascular disease of lipid disorders and chronic inflammation. Guanxinping (GXP) has been administrated in the treatment of AS for nearly 20 years with satisfying clinical response. This study aimed to explore its underlying mechanisms of anti-atherosclerotic effect in AS.

METHODS

Male ApoE^-/- mice were randomized into five groups and fed with either standard diet (control group, CON) or high-fat diet (HFD) for 12 weeks. HFD mice were further divided randomly and either fed continually with HFD as a model group, or atorvastatin (ATO), or low-dose GXP (LGXP), or high-dose GXP (HGXP). After 12 weeks, the body weight, serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-c), and low-density lipoprotein cholesterol (LDL-c) were detected. Moreover, serum inflammation cytokines including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) concentrations were measured. The structure of aortic tissues was examined by hematoxylin-eosin staining. The mRNA expression of TNF-α, IL-6, and IL-1β were assessed by qPCR. The protein expressions of ICAM-1, VCAM-1, MCP-1, IL-6, IL-1β, p38MAPK, ERK1/2, JNK, IκB-α, and NF-κBp65 in the aorta were also detected.

RESULTS

GXP treatment reduced serum TG, TC, and LDL-c levels in ApoE^-/- mice. Moreover, GXP reduced lipid accumulation in the aorta of ApoE^-/- mice, induced by HFD. Furthermore, GXP ameliorated the aorta morphological damage and reduced the serum TNF-α, IL-6, and IL-1β levels. GXP also attenuated the protein expression of ICAM-1, VCAM-1, MCP-1, IL-6, IL-1β, p38MAPK, ERK1/2, JNK, and NF-κBp65, whereas it increased the IκBα level in aortic tissues of ApoE^-/- mice.

CONCLUSIONS

Our results show that GXP could ameliorate atherosclerosis, which is mediated by inhibition of the MAPK/NF-κB signaling pathway in ApoE^-/- mice. This study provides evidence that GXP might be a promising drug for the treatment of AS.

Prevention of Endothelial Dysfunction and Cardiovascular Disease by n-3 Fatty Acids-Inhibiting Action on Oxidative Stress and Inflammation

BACKGROUND

Prospective cohort studies and randomized controlled trials have shown the protective effect of n-3 fatty acids against cardiovascular disease (CVD). The effect of n-3 fatty acids on vascular endothelial cells indicates their possible role in CVD prevention.

OBJECTIVE

Here, we describe the effect of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on endothelial dysfunction-caused by inflammation and oxidative stress-and their role in the development of CVD.

METHODS

We reviewed epidemiological studies done on n-3 fatty acids in CVD. The effect of DHA and EPA on vascular endothelial cells was examined with regard to changes in various markers, such as arteriosclerosis, inflammation, and oxidative stress, using cell and animal models.

RESULTS

Epidemiological studies revealed that dietary intake of EPA and DHA was associated with a reduced risk of various CVDs. EPA and DHA inhibited various events involved in arteriosclerosis development by preventing oxidative stress and inflammation associated with endothelial cell damage. In particular, EPA and DHA prevented endothelial cell dysfunction mediated by inflammatory responses and oxidative stress induced by events related to CVD. DHA and EPA also increased eNOS activity and induced nitric oxide production.

CONCLUSION

The effects of DHA and EPA on vascular endothelial cell damage and dysfunction may involve the induction of nitric oxide, in addition to antioxidant and anti-inflammatory effects. n-3 fatty acids inhibit endothelial dysfunction and prevent arteriosclerosis. Therefore, the intake of n-3 fatty acids may prevent CVDs, like myocardial infarction and stroke.

Protective Effects of Inflammation of Curcumae Longae Rhizoma 30% EtOH Extract on Acute Reflux Esophagitis Rats

Gastroesophageal reflux disease (GERD) is induced by the reflux of stomach contents or gastric acid, pepsin into the esophagus for prolonged periods of time due to defection of the lower esophageal sphincter. Reflux esophagitis is a disease found in less than 50% of GERD patients. This study is aimed at evaluating the protective effect of Curcumae longae Rhizoma 30% EtOH extract (CLR) in acute reflux esophagitis (ARE) rats. CLR measured antioxidant activity through in vitro experiments. Based on the results, we performed experiments in vivo. Before 90 min ARE induction, CLR was administered orally by concentration. ARE was derived by linking the metastatic junction between pylorus and forestomach and corpus in Sprague-Dawley rats. And rats were sacrificed 5 h after surgery. We analyzed the expression of antioxidant and inflammatory-related markers by western blot and observed the production of alanine aminotransferase (ALT), aspartate aminotransferase (AST), reactive oxygen species (ROS), peroxynitrite (ONOO⁻), and thiobarbituric acid reactive substance (TBARS). The administration of CLR reduced esophagus tissue damage in rats with acute reflux esophagitis and decreased the elevated ALT, AST, ROS, ONOO⁻, and TBARS. In addition, CLR effectively increased antioxidant-related factors and reduced inflammatory protein. Overall, these results suggest that CLR would be used as a therapeutic material in protection and treatment for ARE. Overall, CLR treatment informed that markedly ameliorated inactivation of NF-κB led to the inhibition of the expressions of proinflammatory proteins. These results suggest that CLR would be used as a therapeutic material in protection and treatment for ARE.

Cholesterol Homeostasis Modulates Platinum Sensitivity in Human Ovarian Cancer

Despite initial chemotherapy response, ovarian cancer is the deadliest gynecologic cancer, due to frequent relapse and onset of drug resistance. To date, there is no affordable diagnostic/prognostic biomarker for early detection of the disease. However, it has been recently shown that high grade serous ovarian cancers show peculiar oxidative metabolism, which is in turn responsible for inflammatory response and drug resistance. The molecular chaperone TRAP1 plays pivotal roles in such metabolic adaptations, due to the involvement in the regulation of mitochondrial respiration. Here, we show that platinum-resistant ovarian cancer cells also show reduced cholesterol biosynthesis, and mostly rely on the uptake of exogenous cholesterol for their needs. Expression of FDPS and OSC, enzymes involved in cholesterol synthesis, are decreased both in drug-resistant cells and upon TRAP1 silencing, whereas the expression of LDL receptor, the main mediator of extracellular cholesterol uptake, is increased. Strikingly, treatment with statins to inhibit cholesterol synthesis reduces cisplatin-induced apoptosis, whereas silencing of LIPG, an enzyme involved in lipid metabolism, or withdrawal of lipids from the culture medium, increases sensitivity to the drug. These results suggest caveats for the use of statins in ovarian cancer patients and highlights the importance of lipid metabolism in ovarian cancer treatment.

Metabolic Perturbations and Severe COVID-19 Disease: Implication of Molecular Pathways

Coronavirus disease (COVID-19) is caused by SARS-CoV-2 virus, which can result in serious respiratory illnesses such as pneumonia leading to respiratory failure. It was first reported in Wuhan, Hubei, China, in December 2019 and rapidly spread globally, becoming a pandemic in March 2020. Among comorbidities observed in SARS-CoV-2 positive patients, hypertension (68.3%) and type 2-diabetes (30.1%) are the most frequent conditions. Although symptoms are highly heterogeneous (ranging from absence of symptoms to severe acute respiratory failure), patients with metabolic-associated diseases often experience worse COVID-19 outcomes. This review investigates the association between metabolic disorders and COVID-19 severity, exploring the molecular mechanisms potentially underlying this relationship and those that are responsible for more severe COVID-19 outcomes. In addition, the role of the main biological processes that may connect metabolic alterations to SARS-CoV-2 infection such as hyperglycemia, immune system deregulation, ACE-2 receptor modulation, and inflammatory response is described. The impact of metabolic disorders on the prognosis of COVID-19 has major implications in public health especially for countries affected by a high incidence of metabolic diseases.

Angiotensin II increases angiogenesis by NF-κB-mediated transcriptional activation of angiogenic factor AGGF1

Angiogenic factor with G-patch and FHA domains 1 (AGGF1) is involved in vascular development, angiogenesis, specification of hemangioblasts, and differentiation of veins. When mutated, however, it causes Klippel-Trenaunay syndrome, a vascular disorder. In this study, we show that angiotensin II (AngII)-the major effector of the renin-angiotensin system and one of the most important regulators of the cardiovascular system-induces the expression of AGGF1 through NF-κB, and that AGGF1 plays a key role in AngII-induced angiogenesis. AngII significantly up-regulated the levels of AGGF1 mRNA and protein in HUVECs at concentrations of 10-40 μg/ml but not >60 μg/ml. AngII type 1 receptor (AT1R) inhibitor losartan inhibited AngII-induced up-regulation of AGGF1, whereas AT2R inhibitor PD123319 further increased AngII-induced up-regulation of AGGF1. Up-regulation of AGGF1 by AngII was blocked by NF-κB inhibitors, and p65 binds directly to a binding site at the promoter/regulatory region of AGGF1 and transcriptionally activates AGGF1 expression. AngII-induced endothelial tube formation was blocked by small interfering RNAs (siRNAs) for RELA (RELA proto-oncogene, NF-κB subunit)/p65 or AGGF1, and the effect of RELA siRNA was rescued by AGGF1. AngII-induced angiogenesis from aortic rings was severely impaired in Aggf1^+/- mice, and the effect was restored by AGGF1. These data suggest that AngII acts as a critical regulator of AGGF1 expression through NF-κB, and that AGGF1 plays a key role in AngII-induced angiogenesis.-Si, W., Xie, W., Deng, W., Xiao, Y., Karnik, S. S., Xu, C., Chen, Q., Wang, Q. K. Angiotensin II increases angiogenesis by NF-κB-mediated transcriptional activation of angiogenic factor AGGF1.

Effects of Tianxiangdan Granule treatment on atherosclerosis via NF‑κB and p38 MAPK signaling pathways

The present study aimed to determine the effects of Tianxiangdan Granule on nuclear factor (NF)-κB p65 and p38 mitogen-activated protein kinase (MAPK) inflammatory signaling pathways, and explored the possible mechanism underlying the effects of Tianxiangdan Granule on prevention and treatment of atherosclerosis. A total of 48 apolipoprotein E^−/− mice (age, 8 weeks) were selected and divided into two groups: The normal control group (n=12) and the modeling group (n=36). In the modeling group, mice were fed a high-fat diet and were maintained in an artificial climate box, in order to stimulate the climate and eating habit characteristics of Xinjiang. Every morning, ApoE−/− mice in the modeling group were placed in the artificial climate box at 10:00 am and were taken out at 09:00 pm and placed back in the room temperature environment. The temperature of the artificial climate box was set at 6±2°C, relative humidity was controlled at 25–32.8% and the light-dark cycle was 12 h/day. The purpose of this method was to establish the Huizhuo Tanzu type atherosclerosis model. Following successful generation of the model, mice in the modeling group were randomly divided into three groups: Model group (n=10), Tianxiangdan group (n=10) and atorvastatin group (n=10). After 12 weeks, mice were sacrificed and the serum levels of interleukin (IL)-1β and tumor necrosis factor (TNF)-α in each group were detected. Furthermore, the expression levels of NF-κB p65 and p38 MAPK in aortic tissue were detected. The results indicated that the concentrations of IL-1β and TNF-α were significantly higher in mice in the model group compared with in the normal control group (P<0.01), whereas the concentrations of IL-1β and TNF-α were lower in the Tianxiangdan and atorvastatin groups compared with in the model group (P<0.01). Furthermore, the protein expression levels of phosphorylated (p)-NF-κB p65 and p-p38 MAPK protein were higher in aortic tissues from the model group compared with in the normal control group (P<0.01), p-NF-κB p65 and p-p38 MAPK protein expression was reduced in the atorvastatin and Tianxiangdan groups compared with in the model group. The present study indicated that the mechanism underlying the effects of Tianxiangdan Granule on the prevention and treatment of atherosclerosis may be as follows: Tianxiangdan Granule may decrease the expression of the inflammatory cytokines IL-1β and TNF-α, and suppress activation of the NF-κB p65 and p38 MAPK signaling pathways.

Paeoniflorin inhibits proliferation of endometrial cancer cells via activating MAPK and NF-κB signaling pathways

Paeoniflorin (PAE), a principal bioactive component of Paeonia lactiflora Pall., appears to have antitumor properties. However, the pharmacological activity of PAE in endometrial cancer and the specific mechanisms have remained largely elusive. The present study aimed to determine the antitumor activity of PAE in the human endometrial cancer cell line RL95-2 and explore the potential mechanisms. Cell proliferation was assessed to evaluate the antitumor effect of PAE towards RL95-2 cells via a Cell Counting Kit-8 assay. Protein expression was examined to investigate changes in the signaling pathways of p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and nuclear factor (NF)-κB in RL95-2 cells during PAE treatment by western blot analysis. The results revealed that PAE significantly and dose- and time-dependently inhibited the proliferation of RL95-2 cells. In addition, PAE activated MAPK signaling pathways (p38, JNK and ERK) and the NF-κB signaling pathway. Furthermore, p38 MAPK and NF-κB inhibitors (SB203580 and MG-132, respectively) prevented PAE-induced proliferative inhibition in RL95-2 cells. However, ERK and JNK inhibitors (PD98059 and BI-78D3, respectively) did not produce such an inhibition. In conclusion, the present study demonstrated that PAE exerts its anti-proliferative activity via activating p38 MAPK and NF-κB signaling pathways in endometrial cancer cells, providing a potential new drug of choice for endometrial cancer therapy.

The role of endothelial lipase in lipid metabolism, inflammation, and cancer

Endothelial lipase (LIPG) plays a critical role in lipoprotein metabolism, cytokine expression, and the lipid composition of cells. Thus far, the extensive investigations of LIPG have focused on its mechanisms and involvement in metabolic syndromes such as atherosclerosis. However, recent developments have found that LIPG plays a role in cancer. This review summarizes the field of LIPG study. We focus on the role of LIPG in lipid metabolism and the inflammatory response, and highlight the recent insights in its involvement in tumor progression. Finally, we discuss potential therapeutic strategies for targeting LIPG in cancer, and the therapeutic potential of LIPG as a drug target.

Effect of TRPV4-p38 MAPK Pathway on Neuropathic Pain in Rats with Chronic Compression of the Dorsal Root Ganglion

The aim of this study was to investigate the relationships among TRPV4, p38, and neuropathic pain in a rat model of chronic compression of the dorsal root ganglion. Mechanical allodynia appeared after CCD surgery, enhanced via the intrathecal injection of 4α-phorbol 12,13-didecanoate (4α-PDD, an agonist of TRPV4) and anisomycin (an agonist of p38), but was suppressed by Ruthenium Red (RR, an inhibitor of TRPV4) and SB203580 (an inhibitor of p38). The protein expressions of p38 and P-p38 were upregulated by 4α-PDD and anisomycin injection but reduced by RR and SB203580. Moreover, TRPV4 was upregulated by 4α-PDD and SB203580 and downregulated by RR and anisomycin. In DRG tissues, the numbers of TRPV4- or p38-positive small neurons were significantly changed in CCD rats, increased by the agonists, and decreased by the inhibitors. The amplitudes of ectopic discharges were increased by 4α-PDD and anisomycin but decreased by RR and SB203580. Collectively, these results support the link between TRPV4 and p38 and their intermediary role for neuropathic pain in rats with chronic compression of the dorsal root ganglion.

The Effects of NF-κB and c-Jun/AP-1 on the Expression of Prothrombotic and Proinflammatory Molecules Induced by Anti-β2GPI in Mouse

Our previous data demonstrated that nuclear factor-κB (NF-κB) and activator protein-1 (AP-1) are involved in the process of anti-β₂GPI/β₂GPI-induced tissue factor (TF) expression in monocytes. However, the role of NF-κB and AP-1 in pathogenic mechanisms of antiphospholipid syndrome (APS) in vivo has been rarely studied. This study aimed to investigate whether NF-κB and c-Jun/AP-1 are involved in anti-β₂GPI-induced expression of prothrombotic and proinflammatory molecules in mouse. IgG-APS or anti-β₂GPI antibodies were injected into BALB/c mice in the presence or absence of PDTC (a specific inhibitor of NF-κB) and Curcumin (a potent inhibitor of AP-1) treatment. Our data showed that both IgG-APS and anti-β₂GPI could induce the activation of NF-κB and c-Jun/AP-1 in mouse peritoneal macrophages. The anti-β₂GPI-induced TF activity in homogenates of carotid arteries and peritoneal macrophages from mice could significantly decrease after PDTC and/or Curcumin treatment, in which PDTC showed the strongest inhibitory effect, but combination of two inhibitors had no synergistic effect. Furthermore, anti-β₂GPI-induced expression of TF, VCAM-1, ICAM-1 and E-selectin in the aorta and expression of TF, IL-1β, IL-6 and TNF-α in peritoneal macrophages of mice were also significantly attenuated by PDTC and/or Curcumin treatment. These results indicate that both NF-κB and c-Jun/AP-1 are involved in regulating anti-β₂GPI-induced expression of prothrombotic and proinflammatory molecules in vivo. Inhibition of NF-κB and c-Jun/AP-1 pathways may be beneficial for the prevention and treatment of thrombosis and inflammation in patients with APS.

5-Fluoruracil blocked giant cell tumor progression by suppressing osteoclastogenesis through NF-kappaB signals and blocking angiogenesis

Giant cell tumor of bone (GCTB) is a bone destroying tumor comprised of spindle-like stromal cells and monocytes of myeloid lineage that are differentiated into osteoclast-like multinucleated giant cells. Nuclear factor-Kappa B (NF-κB) has been identified to be essential for GCT progression. Herein, we found that 5-Fluorouracil (5-FU), a widely used chemotherapeutics, is a promising anticancer agent for GCT both targeting spindle-like stromal cells and osteoclast giant cells through NF-κB pathway. In this study, in vitro 5-FU not only directly blocked both stromal cell- and RANKL-induced osteoclastogenesis through NF-κB pathway, but also indirectly inhibited osteoclast formation and angiogenesis by suppressing the expression of osteoclast-activating factors including IL-1β, MCP-1 and tumor angiogenesis factor VEGF in stromal cells. In vivo, we found that 5-FU blocked GCT progression through NF-κB pathway by utilizing our chick embryo chorioallantoic membrane (CAM) model. Taken together, our results suggest that 5-FU can inhibit GCT development by suppressing osteoclast formation through NF-κB pathway and blocking angiogenesis, and may serve as a novel agent in the treatment of GCT.

Inflammation, oxidative stress and renin angiotensin system in atherosclerosis

Atherosclerosis is a chronic inflammatory disease associated with cardiovascular dysfunction including myocardial infarction, unstable angina, sudden cardiac death, stroke and peripheral thromboses. It has been predicted that atherosclerosis will be the primary cause of death in the world by 2020. Atherogenesis is initiated by endothelial injury due to oxidative stress associated with cardiovascular risk factors including diabetes mellitus, hypertension, cigarette smoking, dyslipidemia, obesity, and metabolic syndrome. The impairment of the endothelium associated with cardiovascular risk factors creates an imbalance between vasodilating and vasoconstricting factors, in particular, an increase in angiotensin II (Ang II) and a decrease in nitric oxide. The renin-angiotensin system (RAS), and its primary mediator Ang II, also have a direct influence on the progression of the atherosclerotic process via effects on endothelial function, inflammation, fibrinolytic balance, and plaque stability. Anti-inflammatory agents [statins, secretory phospholipase A2 inhibitor, lipoprotein-associated phospholipase A2 inhibitor, 5-lipoxygenase activating protein, chemokine motif ligand-2, C-C chemokine motif receptor 2 pathway inhibitors, methotrexate, IL-1 pathway inhibitor and RAS inhibitors (angiotensin-converting enzyme inhibitors)], Ang II receptor blockers and ranin inhibitors may slow inflammatory processes and disease progression. Several studies in human using anti-inflammatory agents and RAS inhibitors revealed vascular benefits and reduced progression of coronary atherosclerosis in patients with stable angina pectoris; decreased vascular inflammatory markers, improved common carotid intima-media thickness and plaque volume in patients with diagnosed atherosclerosis. Recent preclinical studies have demonstrated therapeutic efficacy of vitamin D analogs paricalcitol in ApoE-deficient atherosclerotic mice.

Effect of paricalcitol and enalapril on renal inflammation/oxidative stress in atherosclerosis

AIM: To investigate the protective effect of paricalcitol and enalapril on renal inflammation and oxidative stress in ApoE-knock out mice.

METHODS: Animals treated for 4 mo as group (1) ApoE-knock out plus vehicle, group (2) ApoE-knock out plus paricalcitol (200 ng thrice a week), (3) ApoE-knock out plus enalapril (30 mg/L), (4) ApoE-knock out plus paricalcitol plus enalapril and (5) normal. Blood pressure (BP) was recorded using tail cuff method. The kidneys were isolated for biochemical assays using spectrophotometer and Western blot analyses.

RESULTS: ApoE-deficient mice developed high BP (127 ± 3 mmHg) and it was ameliorated by enalapril and enalapril plus paricalcitol treatments but not with paricalcitol alone. Renal malondialdehyde concentrations, p22^phox, manganese-superoxide dismutase, inducible nitric oxide synthase (NOS), monocyte chemoattractant protein-1, tumor necrosis factor-alpha and transforming growth factor-β1 levels significantly elevated but reduced glutathione, CuZn-SOD and eNOS levels significantly depleted in ApoE-knock out animals compared to normal. Administration of paricalcitol, enalapril and combined together ameliorated the renal inflammation and oxidative stress in ApoE-knock out animals.

CONCLUSION: Paricalcitol and enalapril combo treatment ameliorates renal inflammation as well as oxidative stress in atherosclerotic animals.

Angiotensin type 1 receptor mediates chronic ethanol consumption-induced hypertension and vascular oxidative stress

OBJECTIVES

We hypothesized that chronic ethanol intake enhances vascular oxidative stress and induces hypertension through renin-angiotensin system (RAS) activation.

METHODS AND RESULTS

Male Wistar rats were treated with ethanol (20% v/v). The increase in blood pressure induced by ethanol was prevented by losartan (10mg/kg/day; p.o. gavage), a selective AT1 receptor antagonist. Chronic ethanol intake increased plasma renin activity (PRA), angiotensin converting enzyme (ACE) activity, plasma angiotensin I (ANG I) and angiotensin II (ANG II) levels and serum aldosterone levels. No differences on plasma osmolality and sodium or potassium levels were detected after treatment with ethanol. Ethanol consumption did not alter ACE activity, as well as the levels of ANG I and ANG II in the rat aorta or mesenteric arterial bed (MAB). Ethanol induced systemic and vascular oxidative stress (aorta and MAB) and these effects were prevented by losartan. The decrease on plasma and vascular nitrate/nitrite (NOx) levels induced by ethanol was prevented by losartan. Ethanol intake did not alter protein expression of ACE, AT1 or AT2 receptors in both aorta and MAB. Aortas from ethanol-treated rats displayed decreased ERK1/2 phosphorylation and increased protein expression of SAPK/JNK. These responses were prevented by losartan. MAB from ethanol-treated rats displayed reduced phosphorylation of p38MAPK and ERK1/2 and losartan did not prevent these responses.

CONCLUSIONS

Our study provides novel evidence that chronic ethanol intake increases blood pressure, induces vascular oxidative stress and decreases nitric oxide (NO) bioavailability through AT1-dependent mechanisms.