NLRC5 deficiency promotes myocardial damage induced by high fat diet in mice through activating TLR4/NF-κB.

The metabolic syndrome could be induced by high fat diet, leading to cardiovascular diseases, such as myocardial damage. Inflammation response and oxidative stress have been reported to be involved in high fat-induced heart injury, and the molecular mechanism is not fully understood. The NOD-like protein family member, NLRC5, could interact with IKKα to inhibit IKK complex activation. In our study, high fat diet-feeding mice showed cardiac fibrosis, inflammation and oxidative stress through collagen accumulation, TLR4/NF-κB and MAPKs signaling pathways activation. NLRC5 knockout mice fed with high fat showed accelerated fibrosis and inflammation response by promoting α-SMA, Collagen I, Collagen III, TLR4/MyD88, phosphorylated IKKα, IκBα and NF-κB expression. And no effect on oxidative stress was observed in wild type and NLRC5-deficiency samples in in vivo studies. Moreover, NLRC5-knockout and -knockdown cardiac muscle cells challenged with LPS also exhibited aggravated fibrosis levels and inflammatory response without any influences on ROS production in in vitro studies. In conclusion, the findings indicated that NLRC5 showed important effects on high fat-induced heart injury via fibrosis and inflammation modulation, providing an essential target for improving myocardial damage induced by high fat diet.

Liquiritigenin attenuates cardiac injury induced by high fructose-feeding through fibrosis and inflammation suppression.

Diabetes combined with cardiomyopathy is considered as an essential complication, showing diastolic persistently and causing cardiac injury, which is linked to fibrosis progression and inflammation response. Fibrosis and inflammation response are two markers for cardiomyopathy. Liquiritigenin is a flavanone, isolated from Radix glycyrrhiza, which exhibits various biological properties, including anti-cancer and anti-inflammatory activities. Here, in our study, the protective effects and anti-inflammatory activity of liquiritigenin were explored in mice and cardiac muscle cells treated by fructose to reveal the possible mechanism by which liquiritigenin attenuates cardiac injury. The mice were separated into five groups. The diabetic model of mouse was established with 30% high fructose feeding. Liquiritigenin dramatically reduced the lipid accumulation induced by high fructose diet. Compared to mice only treated with high fructose, mice in the presence of liquiritigenin after fructose feeding developed less cardiac fibrosis with lower levels of alpha smooth muscle-actin (α-SMA), Collagen type I, Collagen type II, TGF-ß1 and Procol1a1. Additionally, liquiritigenin markedly down-regulated inflammatory cytokines secretion and phosphorylated NF-κB via inhibiting IKKα/IκBα signaling pathway. Our results indicate that liquiritigenin has a protective role in high fructose feeding-triggered cardiac injury through fibrosis and inflammation response suppression by inactivating NF-κB signaling pathway. Thus, liquiritigenin may be a potential candidate for diabetes-associated cardiac injury.

Relation between development of cardiovascular disease and the C242T CYBA polymorphism of the NADPH oxidase in ESRD patients.

BACKGROUND: The development of cardiovascular disease in ESRD patients is considered to be associated with oxidative stress. NAD(P)H oxidase has attracted attention as mechanisms of generating oxidative stress. We investigated the relation between the genotype of the C242T CYBA polymorphism of the NADPH oxidase and the development of cardiovascular disease in ESRD patients. METHODS: A total of 289 ESRD patients were recruited and allocated to one of the two groups: patients without cardiovascular disease (group N; n=192) and patients developing cardiovascular disease (group D; n=97). The C242T CYBA polymorphism was determined by RFLP-PCR methods. RESULTS: The frequency of the C242T CT+TT genotype was significantly lower in group D than in group N (9.1 vs. 20.2%). In multiple Logistic regression analysis, systolic blood pressure, smoking history and this gene polymorphism were shown to be independent variables for the development of cardiovascular disease in ESRD patients. CONCLUSIONS: These results suggest that assessment of the C242T CYBA polymorphism of the NADPH oxidase may be useful in identifying the risk for developing cardiovascular disease in ESRD patients.

[Effect of simvastatin on the reserve of heart function and endothelial function in X-syndrome].

OBJECTIVE: To determine the therapeutic effect of simvastatin combined with traditional medicine on patients with X-syndrome, and on the reserve of heart function and endothelial function. METHODS: Forty patients with X-syndrome were recruited from September 2006 to September 2007 and randomly divided into 2 groups (a simvastatin group and a control group). The control group received routine treatment including beta receptor blocker, calcium-channel blocker (CCB) and long active nitrate. The simvastatin group received simvastatin and the routine treatment. The clinical condition and exercise test (TET) were performed before and after the treatment.The levels of triglyeride (TG), total cholesterol (TC), low density lipoprotein (LDL-C), high density lipoprotein (HDL-C), endothelin-1 (ET-1) and nitric oxide (NO) were measured. RESULTS: The frequencies of chest pain in the simvastatin group were lower than those in the control group. The levels of ET-1, ET-1/NO, TG, TC, and LDL-C were significantly decreased in the simvastatin group as compared with the control group after the treatment. The levels of HDL-C and NO were significantly increased in the simvastatin group as compared with the control group after the treatment. The time in TET was significantly increased in the simvastatin group as compared with the control group. The frequencies of chest pain were positively related to the level of ET-1/NO and negatively related to the time in TET. CONCLUSION: Simvastatin is effective for patients with X-syndrome and may improve the endothelial function and the reserve of heart function.

Association of angiotensin-converting enzyme and endothelial Nitric Oxide synthase gene polymorphisms with vascular disease in ESRD patients in a Chinese population.

BACKGROUND: The effect of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and endothelial Nitric Oxide synthase (eNOS) gene G894 --> T on vascular disease in end-stage renal disease (ESRD) patients was rarely studied previously. We investigated such effect in a Chinese population. METHODS: A total of 153 ESRD patients with vascular disease (88 men and 65 women; mean age +/- SD: 54.0 +/- 13.2) were recruited. Polymerase chain reaction was used to classify the ACE genotypes as II, ID and DD and the eNOS genotypes as GG, GT, and TT. Analyses were performed in ESRD patients with vascular disease (n = 153) and the age-matched controls (n = 148). RESULTS: The frequencies of ACE DD and eNOS TT genotypes and ACE D and eNOS T alleles in ESRD patients with vascular disease were significantly higher than those in the controls (P < 0.05). There was a significant interaction between ACE I/D alleles and eNOS G894 --> T polymorphism: adjusted odds ratio 2.128 (95%CI 1.022-4.434, P = 0.017). CONCLUSIONS: These results indicated that the etiology of vascular disease in ESRD patients is associated with ACE and eNOS (G894 --> T) gene polymorphisms. Our data also suggest that an interaction effect may exist between ACE (I/D) and eNOS (G894 --> T) polymorphism in increasing the risk of vascular complications in ESRD patients.

[Effect of diet control combined with aerobic exercise on the metabolic syndrome].

OBJECTIVE: To observe the efficacy of diet control and aerobic exercises on the patients with metabolic syndrome(MS). METHODS: Sixty sedentary patients with MS were randomly divided into a diet control group, an aerobic exercise group, and a diet control combined with aerobic exercise group, each group with 20 persons. Patients in the simple diet control group ate a low-salt, low-cholesterol, low-calorie and high-cellulose diet; patients in the simple aerobic exercises group performed aerobic exercise 30 minutes every time, 3-5 times per week for 12 weeks; while patients in the combination therapy group performed aerobic exercises and diet control. Fasting serum insulin and free fatty acid (FFA) were measured by radio immunity and enzyme-colorimetric method. Serum leptin concentration was measured by enzyme linked immunosorbent assay (ELISA). Homeostasis model assessment (HOMA) insulin resistance index was calculated using the homeostasis model assessment equation. Twenty healthy subjects were selected as the control group. RESULTS: Serum concentration of FFA, blood pressure, and leptin and insulin resistance index (IRI)of patients with MS significantly increased compared with those of the controls. After 12 weeks, IRI and body mass index (BMI)significantly decreased but blood fat and leptin did not change significantly in the diet control group. IRI and BMI significantly decreased, and triglyceride, FFA and leptin also significantly decreased in the combination therapy group. CONCLUSION: Simple diet control and aerobic exercises are beneficial for patients with MS. It could significantly improve the effect of diet control combined with aerobic exercises on patients with metabolic syndrome.

[Effect of BST on synapse protein SYT and SYN in the hippocampus of chronic stress depression in rats].

OBJECTIVE: To explore the effects of Baisong tablets (BST) on synapse protein synatotagmin (SYT) and synaptophysin (SYN) of hippocampus in chronic stress depression in rats. METHODS: Twenty eight male Sprague-Dawley rats were randomly allocated to 4 groups: a normal control group,a model group,a fluoxetine (FXT) group and a BST group. The normal control rats were fed in a natural environment. Rats of the model, FXT and BST groups were singly housed and given an chronic unpredicted sequence of mild stressors. The distribution and expression differences of SYT and SYN in the hippocampus of rats in different groups were investigated with in situ hybridization and immunoblotting. RESULTS: Expressions of SYT and SYN in the hippocampus of model rats were significantly reduced, compared with that of the normal control (P<0.05); and the expressions of SYT and SYN were significantly increased in the hippocampus of the FXT and BST groups, compared with that of the model group (P<0.05). CONCLUSION: The expressions of SYT and SYN protein and their mRNA decrease in the hippocampus of stress-model rats. BST can up-regulate their expression.