Effect of Quercetin on Atherosclerosis Based on Expressions of ABCA1, LXR-α and PCSK9 in ApoE-/- Mice.

OBJECTIVE: To investigate the effect of quercetin on ATP binding cassette transporter A1 (ABCA1), liver X receptor (LXR), and proprotein convertase subtilisin/kexin type 9 (PCSK9) expressions in apoE-knockout (ApoE-/-) mice. METHODS: The high-fat diet-induced atherosclerosis (AS) in ApoE-/- mice was established. Thirty-six mice were divided into 3 groups using random number table method: model group (n=12), quercetin group (n=12), and atorvastatin group (n=12), with C57BL/6J mice of the same strain and age as the control group (n=12). Quercetin group and atorvastatin group were administrated with quercetin and atorvastatin by oral gavage, with doses of 12.5 and 4 mg/(kg•d), respectively. Animals in the control and model groups were given an equal volume of distilled water by oral gavage once per day for a total of 12 weeks. Western blot and immunohistochemical methods were employed to determine the aortic ABCA1, LXR-α and PCSK9 protein expression. Enzyme linked immunosorbent assay method was used to detect the expression of serum total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-10, combined with tissue pathological examination. RESULTS: ApoE-/- mice fed with a high-fat diet had notable atherosclerosis lesions, with reduced ABCA1, LXR-α and IL-10 levels (all P<0.01), elevated PCSK9, TNF-α and IL-6 expression, and increased TC and LDL-C contents (all P<0.01). After quercetin intervention, the areas of AS plaques and the expressions of PCSK9, TNF-α and IL-6 were significantly reduced (all P<0.01), while the expressions of ABCA1 and LXR-α were increased significantly (all P<0.01). CONCLUSION: Quercetin effectively interfered with AS development by regulating the expressions of ABCA1, LXR- α and PCSK9 in ApoE-/- mice.

Tiaoxin Recipe, a Chinese herbal formula, inhibits microRNA-34a expression in the APPswe/PS1ΔE9 mouse model of Alzheimer's disease.

OBJECTIVE: To investigate the effect and underlying mechanisms of Tiaoxin Recipe (a Chinese herbal formula) treatment on Alzheimer's disease (AD). METHODS: Twelve-week-old APPswe/PS1ΔE9 (APP/PS1) double transgenic mice were used as a model of AD-afflicted mice. One group of mice was treated with Tiaoxin Recipe by gastrogavage for 12 weeks, while two other groups were given intraperitoneal injections of nicotinamide adenine dinucleotide or FK866 for 4 weeks. Morris water maze and thioflavin S staining tests were performed to evaluate cognitive impairment and amyloid plaque deposition, respectively. Serum amyloid-ß1-42 (Aß1-42) content was detected using an enzyme-linked immunosorbent assay, and quantitative reverse transcription-polymerase chain reaction was performed to examine the expression levels of microRNA-34a (miR-34a) in cortex and hippocampus samples of the study mice. RESULTS: Compared with the normal control group, the memory and learning abilities of the APP/PS1 model group were found to be impaired (P < 0.01), as shown by the increased levels of senile plaque deposition in cortex and hippocampus (P < 0.01), miR-34a expression (P < 0.01) and serum Aß1-42 content (P < 0.01). Treatment with Tiaoxin Recipe significantly reduced memory impairment (P < 0.01) by reducing amyloid plaque accumulation in cortex and hippocampus (P < 0.01), miR-34a expression (P < 0.01) and serum Aß1-42 content (P < 0.01) in APP/PS1 mice. CONCLUSION: Tiaoxin Recipe is a viable complementary or alternative therapeutic treatment that is capable of delaying the development of early-stage AD by inhibiting the expression of miR-34a.

Quercetin protects against ox­LDL­induced injury via regulation of ABCAl, LXR­α and PCSK9 in RAW264.7 macrophages.

Quercetin is a flavonoid that has anti­inflammatory, anti­oxidant and lipid metabolic effects. It has also been reported to reduce the risk of cardiovascular disease. The present study measured the effects of quercetin on the expression of ATP­binding cassette transporter 1 (ABCAl), ATP­binding cassette sub­family G member 1 (ABCG1), liver X receptor­α (LXR­α), proprotein convertase subtilisin/kexin type 9 (PCSK9), p53, p21 and p16 induced by oxidized low density lipoprotein (ox­LDL). RAW264.7 macrophages were exposed to ox­LDL with or without 20 µmol/l quercetin and cell proliferation and senescence were quantified using ß­gal staining. Superoxide dismutase (SOD), malondialdehyde (MDA) and lipid droplets were measured in the cytoplasm using oil red staining, while intracellular and total cholesterol (TC) were measured using filipin staining and a TC kit. Immunofluorescent studies and western blot analysis were performed to quantify the expression of ABCAl, ABCG1, LXR­α, PCSK9, p53, p21 and p16. Quercetin increased RAW264.7 cell viability and reduced lipid accumulation, senescence, lipid droplets, intracellular cholesterol and TC. It was concluded that quercetin inhibits ox­LDL­induced lipid droplets in RAW264.7 cells by upregulation of ABCAl, ABCG1, LXR­α and downregulation of PCSK9, p53, p21 and p16.

[Chinese herbal medicine for patients with mild to moderate Alzheimer disease based on syndrome differentiation: a randomized controlled trial].

BACKGROUND: Alzheimer disease (AD) is a chronic neurodegenerative disease that is characterized by its gradual progression. At present, the cause and mechanism of AD are yet unclear, and there is no effective therapy for treating it. With development of global aging, the prevalence rate of AD is increasing. The life quality of elderly people is affected severely by AD that is ultimately life-threatening. Recently, study on treating AD with traditional Chinese medicine (TCM) has deepened. OBJECTIVE: To explore the therapeutic effects of a syndrome differentiation-based TCM regime in treating patients with mild to moderate AD for improving cognition, and to evaluate the changes in brain function of AD patients observed by resting-state functional magnetic resonance imaging (fMRI) technique. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: Adopting the internationally recognized criteria developed by National Institute of Neurological and Communicative Diseases and Stroke/Alzheimer's Disease and Related Disorders Association, the clinical trial was conducted on 131 patients with mild to moderate AD from 5 communities and 7 social welfare institutions. Participants were accepted after informed consent was received, and laboratory tests and a head imaging study were conducted. The patients were randomly divided into Chinese medicine group (CMG) (66 cases) or Western medicine group (WMG) (65 cases). Patients in the CMG were treated monthly with Chinese medicine according to syndrome differentiation. Patients in the WMG were treated with donepezil at a dose of 5 mg once daily. The therapeutic course lasted 48 weeks. MAIN OUTCOME MEASURES: The scores of Mini-Mental State Examination (MMSE), Fuld Object-Memory Evaluation (FOM), Block Design (BD) and Digit Span (DS) were used to evaluate the cognitive function; resting-state fMRI was used for observing brain function. The questionnaires and fMRI were performed before and after treatments. RESULTS: The cognitive functions of the patients in the CMG and WMG were improved after treatment. MMSE score was improved significantly in both groups (P<0.05 or P<0.001). After 48 weeks of treatment, 70.91% patients in the CMG had an improved MMSE score and 20% got worse, however, 55.77% patients in the WMG were improved in MMSE score and 34.62% got worse. Scores of FOM denominator and BD increased significantly in both groups; scores of FOM numerator and DS were also increased in the CMG (P<0.05 or P<0.01). The results of fMRI suggested that both Chinese medicine and donepezil treatment improved the connectivity between posterior cingulated gyrus and specific areas in the brain. The influence range of Chinese medicine primarily impacted on the left parietal lobe, being less than the influence range of donepezil, which primarily affected both sides of frontal lobes. CONCLUSION: TCM treatment based on syndrome differentiation is effective in improving cognitive function of patients with mild to moderate AD and increasing the brain function by increasing connectivity between posterior cingulated gyrus and specific areas in the brain.

ß-amyloid peptide binds and regulates ectopic ATP synthase α-chain on neural surface.

Accumulation of the amyloid ß protein (Aß) in the brain is an important step in the pathogenesis of Alzheimer's disease. Many molecules could bind with Aß, among which some molecules mediate Aß neuronal toxicity. Thus, it is of interest to study the binding proteins of Aß, and the functions that might be affected by Aß. In the present study, we observed that accumulation of α-subunit of ATP synthase is associated with aggregates of Aß proteins in amyloid plaques of amyloid precursor protein/presennillin-1 transgenic mice, and identified the α-subunit of ATP synthase as one of the Aß binding proteins on the plasma membrane of neural cells by Western blot and mass spectrometry. In order to evaluate the consequences of the interaction between Aß and surface α-subunit of ATP synthase, the extracellular ATP generation was analyzed, which showed that aggregated Aß partially inhibited the extracellular generation of ATP, but was unable to significantly induce a decrease in cell surface ATP synthase α on neurons. These results suggest that the cell surface ATP synthase α is a binding protein for Aß on neural cells, the functional inhibition of surface ATP synthase might be involved in machinery of brain malfunction in Aß-mediated pathogenesis of Alzheimer's disease.

Neuronal cell surface ATP synthase mediates synthesis of extracellular ATP and regulation of intracellular pH.

The ATP synthase is known to play important roles in ATP generation and proton translocation within mitochondria. Here, we now provide evidence showing the presence of functional ecto-ATP synthase on the neuronal surface. Immunoblotting revealed that the α, ß subunits of ATP synthase F1 portion are present in isolated fractions of plasma membrane and biotin-labelled surface protein from primary cultured neurons; the surface distribution of α, ß subunits was also confirmed by immunofluorescence staining. Moreover, α and ß subunits were also found in fractions of plasma membrane and lipid rafts isolated from rat brain, and flow cytometry analysis showed α subunits on the surface of acutely isolated brain cells. Activity assays showed that the extracellular ATP generation of cultured neurons could be compromised by α, ß subunit antibodies and ATP synthase inhibitors. pH(i) (intracellular pH) analysis demonstrated that at low extracellular pH, α or ß subunit antibodies decreased pHi of primary cultured neurons. Therefore, ATP synthase on the surface of neurons may be involved in the machineries of extracellular ATP generation and pH(i) homoeostasis.

Effect of probucol and losartan on growth factors after balloon angioplasty in rabbits / 中南大学学报(医学版)

OBJECTIVE@#To investigate the effect of probucol and losartan on the prevention of restenosis after balloon angioplasty in hypercholesterolaemic rabbits, and to examine the expression of growth factors.@*METHODS@#Forty male New Zealand white rabbits were randomly divided into high cholesterol diet group, probucol group, losartan group and combined drugs group. After one week of diet, all rabbits were injured on iliac arteries with balloon. Four weeks after the injury, the morphology of the iliac arteries of the rabbits were observed, and the insulin-like growth factor-I receptor (IGF-IR) and vascular endothelial growth factor (VEGF) were examined by immunohistochemical methods.@*RESULTS@#Compared with the high cholesterol diet group, the lumen areas of the probucol group, losartan group and combined drugs group were larger (P < 0.01), the intimal areas were smaller (P < 0.05), and the expression of IGF-IR and VEGF significantly decreased (P < 0.05). There was no statistically significant difference among the three groups.@*CONCLUSION@#Probucol and losartan can prevent the restenosis of rabbits' iliac artery from balloon injury, and inhibit the expression of IGF-IR and VEGF. There is no statistical difference between combined drugs and single drug administration.

Cox regression analysis on influencing factors of coronary heart disease among people over 40 years of age / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the affecting factors on coronary heart disease among people over 40 years of age in Guangxi area, China.</p><p><b>METHODS</b>Baseline data was gathered through the Third National Blood Pressure Survey in 1991 in China. A total number of 11 818 adults over 40 years old had been studied in Guangxi province. Data of morbidity and mortality of coronary heart disease was obtained.</p><p><b>RESULTS</b>Cardiovascular events were related to systolic blood pressure, diastolic blood pressure, pulse pressure, smoking, BMI regardless of their myocardial infarct (MI) history. Cox regression analysis showed that the relative risk for cardiovascular events increased by 21 [95% confidence interval (CI): 9.06-48.44] times for those people having MI history. When pulse pressure, systolic blood pressure, diastolic blood pressure increased by every 10 mm Hg, the relative risk for cardiovascular events increased by 1.29 (95% CI: 1.11-1.49), 1.18 (95% CI: 1.02-1.22), 1.13 (95% CI: 1.05-1.28) respectively. There was 1.23 (95% Cl: 1.05-1.45) times higher in smoker than non-smoker on relative risk for cardiovascular events. When BMI increasing 1, the relative risk for cardiovascular events would increase 1.03 (95% CI: 1.01-1 .05) times.</p><p><b>CONCLUSION</b>Hypertension, smoking, increase of BMI were the risk factors of coronary heart disease among people who were over 40 years of age.</p>