RÉSUMÉ
BACKGROUND: Alzheimer's disease (AD) is a typical neurodegenerative disease with a complex etiology. Until now, there has been no effective treatment available for AD; however, improving energy dysmetabolism, the key pathological event in the early stage of AD, can effectively delay the progression of AD. OBJECTIVE: This paper aims to investigate the therapeutic effect and potential mechanism of the new Tiaoxin recipe on early AD. METHODS: APP/PS1 mice were divided into a model group, a new Tiaoxin recipe group, and a donepezil group, and C57/BL mice were used for the control group. Mouse cognitive and learning abilities were tested using the Morris water maze test and a new object-recognition experiment. The 42 amino acid form of amyloid ß peptide (Aß1-42) content was detected by enzyme-linked immunosorbent assay, the senile plaque area was detected by thioflavin S staining, and the senescence-associated ß-galactosidase (SA-ß-gal)-positive area was detected by chemical staining. Also, the adenosine triphosphate (ATP), nicotinamide adenine dinucleotide (NAD+), and nicotinamide adenine dinucleotide hydride (NADH) contents were detected using a biochemical method, and the cluster of differentiation 38 (CD38) and silent mating-type information regulation 2 homolog 3 (SIRT3) protein expression levels were detected by immunofluorescence and Western blot analysis. RESULTS: Compared with those of the control group, the learning and memory abilities of the model group were impaired; the senile plaque deposition, Aß1-42 content, and SA-ßgal-positive staining area were increased; the ATP concentration, NAD+ concentration, and NAD+/NADH ratio were decreased; the CD38 protein expression level was increased; and the SIRT3 protein expression level was decreased. Following intervention with the new Tiaoxin recipe, the learning and memory abilities were improved; the senile plaque deposition, Aß1-42 content, and SA-ßgal-positive area were reduced; the ATP concentration, NAD+ concentration, and NAD+/NADH ratio were increased; CD38 protein expression was decreased, and SIRT3 protein expression was increased. CONCLUSION: This study shows that the new Tiaoxin Recipe can improve cognitive ability and reduce the Aß1-42 content and senile plaque deposition in APP/PS1 mice, which may occur through the downregulation of CD38 protein expression, upregulation of SIRT3 protein expression, restoration of the NAD+ level, promotion of ATP synthesis, mitigation of energy metabolism disorders.
RÉSUMÉ
BACKGROUND: In Alzheimer's disease (AD), the neuroinflammatory response mediated by the activation of senescent microglia is closely related to energy dysmetabolism. However, the mechanism underlying the interaction between the energy metabolism of aging microglia and neuroinflammation remains unclear. METHODS: We used biochemical methods, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, and western blot to determine the effects and mechanism of CD38 knockdown on energy metabolism and neuroinflammation in Aß1-40 injured BV2 cells. Using AD model mice, we detected CD38 enzyme activity, energy metabolism factors (ATP, NAD +, and NAD + /NADH), and neuroinflammatory factors (IL-1ß, IL-6, and TNF-α) following the addition of CD38 inhibitor. Using a combination of biochemical analysis and behavioral testing, we analyzed the effects of the CD38 inhibitor on energy metabolism disorder, the neuroinflammatory response, and the cognition of AD mice. RESULTS: Following Aß1-40 injury, SA-ß-Gal positive cells and senescence-related proteins P16 and P21 increased in BV2 cells, while energy-related molecules (ATP, NAD +, and NAD + /NADH) and mitochondrial function (mitochondrial ROS and MMP) decreased. Further studies showed that CD38 knockdown could improve Aß1-40-induced BV2 cells energy dysmetabolism and reduce the levels of IL-1ß, IL-6, and TNF-α. In vivo results showed an increase in senile plaque deposition and microglial activation in the hippocampus and cortex of 34-week-old APP/PS1 mice. Following treatment with the CD38 inhibitor, senile plaque deposition decreased, the number of Iba1 + BV2 cells increased, the energy metabolism disorder was improved, the proinflammatory cytokines were reduced, and the spatial learning ability was improved. CONCLUSIONS: Our results confirm that senescent microglia appeared in the brain of 34-week-old APP/PS1 mice, and that Aß1-40 can induce senescence of BV2 cells. The expression of CD38 increases in senescent BV2 cells, resulting in energy metabolism disorder. Therefore, reducing CD38 expression can effectively improve energy metabolism disorder and reduce proinflammatory cytokines. Following intervention with the CD38 inhibitor in APP/PS1 mice, the energy metabolism disorder was improved in the hippocampus and cortex, the level of proinflammatory cytokines was reduced, and cognitive impairment was improved.
Sujet(s)
Maladie d'Alzheimer , Maladie d'Alzheimer/métabolisme , Animaux , Encéphale , Modèles animaux de maladie humaine , Hippocampe , Souris , Souris transgéniques , MicroglieRÉSUMÉ
BACKGROUND: In Alzheimer's disease (AD), the neuroinflammatory response mediated by the activation of senescent microglia is closely related to energy dysmetabolism. However, the mechanism underlying the interaction between the energy metabolism of aging microglia and neuroinflammation remains unclear. METHODS: We used biochemical methods, enzyme-linked immunosorbent assay (ELISA), immunofluorescence, and western blot to determine the effects and mechanism of CD38 knockdown on energy metabolism and neuroinflammation in Aß1-40 injured BV2 cells. Using AD model mice, we detected CD38 enzyme activity, energy metabolism factors (ATP, NAD +, and NAD +/NADH), and neuroinflammatory factors (IL-1ß, IL-6, and TNF-α) following the addition of CD38 inhibitor. Using a combination of biochemical analysis and behavioral testing, we analyzed the effects of the CD38 inhibitor on energy metabolism disorder, the neuroinflammatory response, and the cognition of AD mice. RESULTS: Following Aß1-40 injury, SA-ß-Gal positive cells and senescence-related proteins P16 and P21 increased in BV2 cells, while energy-related molecules (ATP, NAD +, and NAD +/NADH) and mitochondrial function (mitochondrial ROS and MMP) decreased. Further studies showed that CD38 knockdown could improve Aß1-40-induced BV2 cells energy dysmetabolism and reduce the levels of IL-1ß, IL-6, and TNF-α. In vivo results showed an increase in senile plaque deposition and microglial activation in the hippocampus and cortex of 34-week-old APP/PS1 mice. Following treatment with the CD38 inhibitor, senile plaque deposition decreased, the number of Iba1 +BV2 cells increased, the energy metabolism disorder was improved, the proinflammatory cytokines were reduced, and the spatial learning ability was improved. CONCLUSIONS: Our results confirm that senescent microglia appeared in the brain of 34-week-old APP/PS1 mice, and that Aß1-40 can induce senescence of BV2 cells. The expression of CD38 increases in senescent BV2 cells, resulting in energy metabolism disorder. Therefore, reducing CD38 expression can effectively improve energy metabolism disorder and reduce proinflammatory cytokines. Following intervention with the CD38 inhibitor in APP/PS1 mice, the energy metabolism disorder was improved in the hippocampus and cortex, the level of proinflammatory cytokines was reduced, and cognitive impairment was improved.
Sujet(s)
Animaux , Souris , Maladie d'Alzheimer/métabolisme , Encéphale , Souris transgéniques , Microglie , Modèles animaux de maladie humaine , HippocampeRÉSUMÉ
The BuShen JiangZhi (BSJZ) recipe is a Chinese medicine compound with the effect of tonifying the kidney, replenishing essence, and lowering blood fat to unblock vessels. The purpose of this study is to explore whether the mechanism of BSJZ for effective intervention in the treatment of AS is related to mmu_circRNA_22187 and aminopeptidase N (Anpep). ApoE-/- mice were induced by a high-fat diet to replicate the AS model. 24 ApoE-/- mice were randomly divided into model group (group M), BSJZ group (group BS), and 12 C57BL/6 mice of the same genetic background and same weeks of age as the normal control group (group C). Mice in the BS group were given an aqueous solution of BSJZ by gavage, while mice in groups C and M were given the same volume of distilled water. HE and Oil Red O staining were used to detect the pathomorphology and lipid accumulation of mouse aortic sinus. Arraystar version 2.0 mouse circRNA chip was used to scan with Agilent Scanner G2505C, and the differential circRNAs expression profile of mice aorta was obtained. Scatter plot, volcano plot, and cluster map, respectively, visualized the differentially expressed circRNAs, as well as the types of circRNAs and the chromosomes' distribution, screened and compared the differentially expressed circRNAs intersection between groups by Venny software, and then combined ceRNA bioinformatics analysis to construct a ceRNA network. The results showed that BSJZ could significantly reduce the area of AS plaque and lipid accumulation in the aortic sinus of ApoE-/- mice induced by a high-fat diet. The bioinformatics analysis showed that mmu_circRNA_22187 may be a key circRNA of BSJZ intervention in the treatment of AS. Compared with group C, the expressions of Anpep mRNA and protein were upregulated in group M. After the intervention of BSJZ, the expressions of Anpep mRNA and protein were downregulated. Therefore, BSJZ could effectively treat AS which might be related to the regulation of mmu_circRNA_22187 and Anpep.
RÉSUMÉ
BACKGROUND: The most widely used frailty phenotype and frailty indexes are either time-consuming or complicated, thus restricting their generalization in clinical practice; and therefore, an easier and faster screening tool is needed to be developed. OBJECTIVE: To select sensitive symptoms in traditional Chinese medicine (TCM) and study whether they can improve the risk prediction of frailty. METHODS: This is a cross-sectional study enrolling 2249 Chinese elderly community dwellers. Data were collected via face-to-face inquiries, anthropometric measurements, laboratory tests, and community health files. Frailty was the main outcome measure, and it was evaluated by Fried's frailty phenotype (FP). The ordinal logistic regression model was used to identify the factors associated with frailty. The risk assessment plot was used to compare the discriminative ability for frailty among models with and without TCM symptoms. RESULTS: The identified sensitive influential factors for frailty included age, education level, dietary habits, chronic obstructive pulmonary disease, diabetes, cerebral infarction, osteoporosis, cold limbs, lethargy and laziness in speaking and moving, weakness of lower limbs, slow movement, dry mouth and throat, and glazed expression. The risk prediction for "frailty cumulative components ≥1" was not significantly increased, while for "frailty cumulative components ≥2", a new model developed with the above selected TCM symptoms had a higher AUC than the baseline model without it (0.79 VS 0.81, P=0.002). And the NRI and IDI for the new model were 41.4% (P=0.016) and 0.024% (P=0.041), respectively. CONCLUSION: This research might provide an easier and faster way for early identification and risk prediction of frailty in elderly community dwellers.
RÉSUMÉ
As a systemic syndrome characterized by age-associated degenerative skeletal muscle atrophy, sarcopenia leads to a risk of adverse outcomes in the elderly. Age-related iron accumulation is found in the muscles of sarcopenia animal models and patients, but the role of iron in sarcopenia remains poorly understood. It has been recently found that iron overload in several diseases is involved in ferroptosis, an iron- dependent form of programmed cell death. However, whether this excess iron can result in ferroptosis in muscles is still unclear. In our present study, we found that ferric citrate induced ferroptosis in C2C12 cells, as well as impaired their differentiation from myoblasts to myotubes. Due to the decreased muscle mass and fiber size, 40-week-old senescence accelerated mouse prone 8 (SAMP8) mice were used as a sarcopenia model, in whose muscles the iron content and markers of ferroptosis were found to increase, compared to 8-week- old SAMP8 controls. Moreover, our results showed that iron overload upregulated the expression of P53, which subsequently repressed the protein level of Slc7a11 (solute carrier family 7, member 11), a known ferroptosis-related gene. The downregulation of Slc7a11 then induced the ferroptosis of muscle cells through the accumulation of lipid peroxidation products, which may be one of the causes of sarcopenia. The findings in this study indicate that iron plays a key role in triggering P53- Slc7a11-mediated ferroptosis in muscles, and suggest that targeting iron accumulation and ferroptosis might be a therapeutic strategy for treating sarcopenia.
Sujet(s)
Ferroptose , Fer/métabolisme , Muscles squelettiques/métabolisme , Sarcopénie/métabolisme , Système y+ de transport d'acides aminés/métabolisme , Animaux , Lignée cellulaire , Modèles animaux de maladie humaine , Mâle , Souris , Développement musculaire , Muscles squelettiques/anatomopathologie , Sarcopénie/anatomopathologieRÉSUMÉ
The purpose of the current study was to investigate the mechanism by which fisetin improves atherosclerosis (AS) by regulating lipid metabolism and senescence in apolipoprotein E-deficient (apoE-/-) mice. An AS model was established by feeding apoE-/- mice a high-fat diet. Mice were randomly divided into the model group (n=18), the fisetin group (n=18) and the atorvastatin group (n=18). The control group (n=18) was composed of wild-type C57BL/6 mice of the same age and genetic background. The fisetin and atorvastatin groups were respectively treated with aqueous solutions of fisetin (12.5 mg/kg) and atorvastatin (2 mg/kg) via oral gavage daily for 12 weeks. The pathological morphology, lipid accumulation, collagen deposition of the aortic sinus were observed, serum lipids, superoxide dismutase (SOD) and malondialdehyde (MDA) levels and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were measured in the peripheral blood serum. Additionally, the expressions of proprotein convertase subtilisin/kexin type 9 (PCSK9), lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), tumor suppressor protein p53 (p53), cyclin-dependent kinase inhibitor 1A (p21) and multiple tumor suppressor-1 (p16) were analyzed in the aorta. The results of the current study indicated that compared with the control group, a large area of AS plaque in the aortic sinus that contained a large amount of red-stained lipids and decreased collagen fiber content were found in the model group, which exhibited higher total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), oxidized low-density lipoprotein (ox-LDL) and MDA levels; higher ALT and AST activities, lower high-density lipoprotein cholesterol (HDL-C) and SOD levels and increased expression levels of PCSK9, LOX-1, p53, p21 and p16. Fisetin is a phytochemical and bioflavonoid that serves a potential role in chronic diseases including AS, obesity, diabetes and cancer due to its wide biological activities, such as regulating lipid metabolism and anti-aging, anti-oxidation and anti-inflammatory. Atorvastatin is recognized as a first-line treatment drug for AS; therefore it was used as a positive control in the current study. Following fisetin and atorvastatin treatment, both the AS plaque and the lipid accumulation in the aortic sinus were significantly reduced, and the expressions of PCSK9, LOX-1 and aging markers, including p53, p21 and p16 were downregulated.
RÉSUMÉ
OBJECTIVE: To study the effect of Bushen Jiangzhi formula (BSJZF) on atherosclerosis (AS) in apolipoprotein E knockout (apoE-/-) mice and the underlying mechanism. METHODS: We used a high fat diet to induce AS in apoE-/- mice. The mice were randomly divided into four groups: model, BSJZF, atorvastatin, and 3-methyladenine groups. Syngeneic C57BL/6 mice of the same age were used for the control group. Autophagosomes in the aorta were examined by transmission electron microscopy. Morphology, lipid accumulation, and collagen deposition in the aorta were examined by hematoxylin and eosin, Oil Red O, and Masson's staining, respectively. Serum levels of tumor necrosis factor alpha (TNF-), interferon gamma (IFN-), and interleukin 10 (IL-10) were measured by enzyme-linked immunoassays. Protein expression of microtubule-associated protein light chain 3 (LC3), Beclin 1, and p62 in the aorta were examined by Western blot analyses. RESULTS: ApoE-/- mice fed a high fat diet exhibited AS symptoms including less autophagosomes in the aorta, higher serum levels of TNF-a, IFN-r, and p62, and lower serum levels of IL-10, LC3, and Beclin 1. Treatment with BSJZF significantly reduced the area of the aortic plaque, decreased expression of TNF-a, IFN-r, and p62, and increased expression of IL-10, LC3, and Beclin 1. CONCLUSION: Our findings suggest that BSJZF promotes autophagy and reduces inflammation by regulating the expression of autophagy-related proteins LC3, Beclin 1, and p62, thereby effectively treating AS.
Sujet(s)
Apolipoprotéines E/déficit , Athérosclérose/traitement médicamenteux , Autophagie/effets des médicaments et des substances chimiques , Médicaments issus de plantes chinoises/administration et posologie , Animaux , Aorte/effets des médicaments et des substances chimiques , Aorte/métabolisme , Apolipoprotéines E/génétique , Athérosclérose/génétique , Athérosclérose/métabolisme , Athérosclérose/physiopathologie , Alimentation riche en graisse/effets indésirables , Humains , Mâle , Souris , Souris de lignée C57BL , Souris knockout , Protéines associées aux microtubules/génétique , Protéines associées aux microtubules/métabolisme , Facteur de nécrose tumorale alpha/génétique , Facteur de nécrose tumorale alpha/métabolismeRÉSUMÉ
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/(kgâ¢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.
Sujet(s)
Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP/métabolisme , Athérosclérose/traitement médicamenteux , Athérosclérose/métabolisme , Récepteurs hépatiques X/métabolisme , Proprotéine convertase 9/métabolisme , Quercétine/pharmacologie , Animaux , Aorte/effets des médicaments et des substances chimiques , Alimentation riche en graisse , Souris , Souris de lignée C57BL , Souris invalidées pour les gènes ApoERÉSUMÉ
OBJECTIVE: To investigate the process by which quercetin suppresses atherosclerosis by upregulating MST1-mediated autophagy in RAW264.7 macrophages. METHODS: An in vitro foam cell model was established by culturing RAW264.7 macrophages with oxidized low-density lipoprotein (ox-LDL). The cells were treated with quercetin alone or in combination with the autophagy inhibitor, 3-methyladenine, and autophagy agonist, rapamycin. Cell viability was detected with a CCK-8 kit. Lipid accumulation was detected by oil red O staining, senescence was detected by SA-ß-gal (senescence-associated ß-galactosidase) staining, reactive oxygen species were detected by ROS assay kit. Autophagosomes and mitochondria were detected by transmission electron microscope (TEM), and expression of MST1, LC3-II/I, Beclin1, Bcl-2, P21, and P16 were detected by immunofluorescence and Western blot. RESULTS: Ox-LDL induced RAW264.7 macrophage-derived foam cell formation, reduced survival, aggravated cell lipid accumulation, and induced a senescence phenotype. This was accompanied by decreased formation of autophagosome; increased expression of P53, P21, and P16; and decreased expression of LC3-II/I and Beclin1. After intervention with quercetin, the cell survival rate was increased, and lipid accumulation and senescence phenotype were reduced. Furthermore, the expression of LC3-II/I and Beclin1 were increased, which was consistent with the ability of quercetin to promote autophagy. Ox-LDL also increased the expression of MST1, and this increase was blocked by quercetin, which provided a potential mechanism by which quercetin may protect foam cells against age-related detrimental effects. CONCLUSION: Quercetin can inhibit the formation of foam cells induced by ox-LDL and delay senescence. The mechanism may be related to the regulation of MST1-mediated autophagy of RAW264.7 cells.
Sujet(s)
Athérosclérose/anatomopathologie , Autophagie/effets des médicaments et des substances chimiques , Évolution de la maladie , Cellules spumeuses/métabolisme , Cellules spumeuses/anatomopathologie , Facteur de croissance des hépatocytes/métabolisme , Lipoprotéines LDL/pharmacologie , Protéines proto-oncogènes/métabolisme , Quercétine/pharmacologie , Adénine/analogues et dérivés , Adénine/pharmacologie , Animaux , Survie cellulaire/effets des médicaments et des substances chimiques , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Inhibiteur p16 de kinase cycline-dépendante/métabolisme , Inhibiteur p21 de kinase cycline-dépendante/métabolisme , Cellules spumeuses/effets des médicaments et des substances chimiques , Métabolisme lipidique/effets des médicaments et des substances chimiques , Souris , Cellules RAW 264.7 , Sirolimus/pharmacologie , Régulation positive/effets des médicaments et des substances chimiquesRÉSUMÉ
Alzheimer's disease (AD) is a neurodegenerative disease of the central nervous system that is characterized by progressive cognitive dysfunction and which ultimately leads to dementia. Studies have shown that energy dysmetabolism contributes significantly to the pathogenesis of a variety of agingassociated diseases and degenerative diseases of the nervous system, including AD. One focus of research thus has been how to regulate the expression of nicotinamide phosphoribosyltransferase (NAMPT) to prevent against neurodegenerative diseases. Therefore, the present study used 6monthold APPswe/PS1ΔE9 (APP/PS1) transgenic mice as early AD mouse models and sought to evaluate nicotinamide adenine dinucleotide (NAD+) and FK866 (a NAMPT inhibitor) treatment in APP/PS1 mice to study NAMPT dysmetabolism in the process of AD and elucidate the underlying mechanisms. As a result of this treatment, the expression of NAMPT decreased, the synthesis of ATP and NAD+ became insufficient and the NAD+/NADH ratio was reduced. The administration of NAD+ alleviated the spatial learning and memory of APP/PS1 mice and reduced senile plaques. Administration of NAD+ may also increase the expression of the key protein NAMPT and its related protein sirtuin 1 as well as the synthesis of NAD+. Therefore, increasing NAMPT expression levels may promote NAD+ production. Their regulation could form the basis for a new therapeutic strategy.
Sujet(s)
Acrylamides/antagonistes et inhibiteurs , Maladie d'Alzheimer/métabolisme , Cytokines/effets des médicaments et des substances chimiques , Cytokines/métabolisme , NAD/antagonistes et inhibiteurs , Nicotinamide phosphoribosyltransferase/effets des médicaments et des substances chimiques , Nicotinamide phosphoribosyltransferase/métabolisme , Pipéridines/antagonistes et inhibiteurs , Transduction du signal/physiologie , Acrylamides/pharmacologie , Amyloïde/métabolisme , Animaux , Comportement animal , Cytokines/génétique , Modèles animaux de maladie humaine , Hippocampe/effets des médicaments et des substances chimiques , Apprentissage/effets des médicaments et des substances chimiques , Mâle , Mémoire/effets des médicaments et des substances chimiques , Souris , Souris de lignée C57BL , Souris transgéniques , NAD/métabolisme , NAD/pharmacologie , Nicotinamide phosphoribosyltransferase/génétique , Pipéridines/pharmacologie , Sirtuine-1/métabolismeRÉSUMÉ
To test the hypothesis that the flavonoid compound, fisetin, protects macrophages from lipid accumulation and senescence through regulation of casein kinase 2-interacting protein-1 (CKIP-1)/REGγ (11S regulatory particles, 28â¯kDa proteasome activator, proteasome activator subunit 3) signaling. RAW264.7 macrophage cells were exposed to 100⯵g/ml oxidized low-density lipoprotein (ox-LDL) with or without 20⯵g/ml fisetin for 24â¯h. Cell viability was detected by CCK-8 after 1â¯h. Intracellular lipid accumulation was measured using Oil Red O staining. Total cholesterol (TC) and free cholesterol (FC) contents were measured using assay kits, and cell senescence was inferred by ß-gal staining. Protein expression levels of CKIP-1, REGγ, organic cation transporter 1 (Oct-1), lectin-like oxidized LDL receptor-1 (LOX-1), tumor suppressor protein p53 (p53), cell cycle regulatory protein p21 (p21), and multiple tumor suppressor-1 (p16) were detected by immunofluorescence and confirmed by Western blot. Stimulating RAW264.7 macrophage cells with 100⯵g/ml ox-LDL for 24â¯h induced the formation of foam cells, increased intracellular lipid accumulation, increased TC and FC content, and promoted cell senescence. Furthermore, cells induced with 100⯵g/ml ox-LDL for 24â¯h showed decreased CKIP-1 and REGγ protein, while the expressions of Oct-1, LOX-1, p53, p21 and p16 were increased. In contrast, treatment with 20⯵g/ml fisetin reversed 100⯵g/ml ox-LDL effects to increase cell viability, and decrease ß-gal staining, intracellular lipid levels and TC and FC levels. These beneficial effects were associated with increased CKIP-1 and REGγ and decreased Oct-1, LOX-1, p53, p21, and p16 protein expression. Results indicated that fisetin limited ox-LDL-mediated lipid accumulation and senescence in RAW264.7 macrophage-derived foam cells. The mechanism underlying these effects may involve regulation of CKIP-1/REGγ signaling.
Sujet(s)
Autoantigènes/métabolisme , Protéines de transport/métabolisme , Flavonoïdes/pharmacologie , Cellules spumeuses/effets des médicaments et des substances chimiques , Lipoprotéines LDL/métabolisme , Proteasome endopeptidase complex/métabolisme , Animaux , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Flavonols , Cellules spumeuses/métabolisme , Métabolisme lipidique/effets des médicaments et des substances chimiques , Souris , Cellules RAW 264.7 , Transduction du signal/effets des médicaments et des substances chimiquesRÉSUMÉ
The present study examined the involvement of autophagy as a mechanism in the protective effect of quercetin (QUE) on atherosclerosis (AS) in ApoE-/- mice. An AS model was established by feeding ApoE-/- mice a high-fat diet (HFD). Mice were divided into four experimental groups: The model, QUE, 3-methyladenine (3-MA) and QUE + 3-MA groups. Additionally, age-matched wild-type C57BL/6 mice were used as a Control group. Autophagosomes in the aorta were examined using a transmission electron microscope. Aorta pathology, serum lipid accumulation and collagen deposition were determined by hematoxylin and eosin, Oil Red O and Masson staining, respectively. The levels of cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) were measured using ELISA assays. Protein levels of mTOR, microtubule associated protein 1 light chain 3a (LC3), P53 and cyclin dependent kinase inhibitor 1A (P21) in the aorta were analyzed using western blotting. ApoE-/- mice which were fed HFD exhibited substantial AS pathology, no autophagosomes, higher levels of TNF-α, IL-1ß, IL-18 and mTOR and lower ratios of LC3 II/I. All these alterations were ameliorated and aggravated by QUE and 3-MA treatment, respectively. The inhibition of AS by QUE may be associated with the enhancement of autophagy and upregulation of P21 and P53 expression.
RÉSUMÉ
The aim of this study was to investigate the mechanisms through which quercetin protects against atherosclerosis (AS) in apoE/ mice by regulating the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9), cluster of differentiation 36 (CD36), peroxisome proliferatoractivated receptor γ (PPARγ), liver X receptor α (LXRα) and ATP binding cassette transporter A1 (ABCA1). We established an animal model of highfat diet induced AS using apoE/ mice. H&E, Oil Red O and Masson's trichrome staining were performed on aortic sinus and liver tissue sections to evaluate the histopathology, lipid accumulation and collagen deposition, respectively. Filipin staining was performed to detect free cholesterol (FC) in the aortic sinus. ELISA was performed to measure the serum levels of lipids including total cholesterol (TC), triglyceride (TG), highdensity lipoproteincholesterol (HDLC), lowdensity lipoproteincholesterol (LDLC) and oxidized lowdensity lipoprotein (oxLDL), as well as the levels of inflammatory cytokines, including tumor necrosis factor (TNF)α, interleukin (IL)6 and IL10. Western blot analysis was performed to analyze the protein expression levels of PCSK9, CD36, PPARγ, LXRα and ABCA1 in both the aorta and liver tissue. H&E staining revealed the presence of atherosclerotic plaques in the aortic sinus. Oil Red O staining revealed the existence of massive redstained lipids in the aortic sinus and Masson's trichrome staining revealed decreased collagen fibers and increased plaque instability. Filipin staining revealed that free cholesterol levels in the aorta sinus were increased. In addition, H&E staining suggested hepatocyte structural disorder in the model group, and Oil Red O staining revealed a cytoplasm filled with lipid droplets, which contained a large amount of redstained lipids. Masson's trichrome staining revealed that the liver tissue of the model group had fewer collagen fibers compared with that of the control group. Moreover, the mice in the model group had higher serum TC, LDLC, oxLDL, TNFα and IL6 levels, and lower IL10 levels. The protein expression levels of PCSK9 and CD36 were increased, while those of PPARγ, LXRα and ABCA1 were decreased in the aortas and livers of the model group mice. However, treatment with quercetin attenuated all these effects. On the whole, these results demonstrate that quercetin prevents the development of AS in apoE/ mice by regulating the expression of PCSK9, CD36, PPARγ, LXRα and ABCA1.
Sujet(s)
Antioxydants/pharmacologie , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Quercétine/pharmacologie , Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP/génétique , Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP/métabolisme , Analyse de variance , Animaux , Marqueurs biologiques/sang , Antigènes CD36/génétique , Antigènes CD36/métabolisme , Lipides/sang , Foie/effets des médicaments et des substances chimiques , Foie/métabolisme , Foie/anatomopathologie , Récepteurs hépatiques X/génétique , Récepteurs hépatiques X/métabolisme , Souris , Souris knockout , Récepteur PPAR gamma/génétique , Récepteur PPAR gamma/métabolismeRÉSUMÉ
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 12â¯weeks, while two other groups were given intraperitoneal injections of nicotinamide adenine dinucleotide or FK866 for 4â¯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 (Pâ¯<â¯0.01), as shown by the increased levels of senile plaque deposition in cortex and hippocampus (Pâ¯<â¯0.01), miR-34a expression (Pâ¯<â¯0.01) and serum Aß1-42 content (Pâ¯<â¯0.01). Treatment with Tiaoxin Recipe significantly reduced memory impairment (Pâ¯<â¯0.01) by reducing amyloid plaque accumulation in cortex and hippocampus (Pâ¯<â¯0.01), miR-34a expression (Pâ¯<â¯0.01) and serum Aß1-42 content (Pâ¯<â¯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.
Sujet(s)
Maladie d'Alzheimer/génétique , Maladie d'Alzheimer/thérapie , Peptides bêta-amyloïdes/génétique , Médicaments issus de plantes chinoises/pharmacologie , microARN/génétique , Animaux , Cortex cérébral/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Hippocampe/effets des médicaments et des substances chimiques , Mâle , Médecine traditionnelle chinoise , Souris , Souris transgéniques , Plantes médicinales/composition chimique , RT-PCRRÉSUMÉ
Liver X receptor alpha (LXRα) plays important roles in lipid metabolism and inflammation. Therefore, it is essential for protection against atherosclerosis (AS). In AS plaques, the key cells involved in lipid metabolism and inflammation are macrophages. However, the mechanism by which LXRα regulates macrophage involvement in AS formation remains unclear. In this study, we first confirmed the effects of an LXRα agonist (T0901317) and antagonist (GSK2033) on foam cell formation and inflammation in vivo and in vitro. Indeed, T0901317 reduced the number of macrophages in AS plaques and decreased the number of migrated macrophages, as assessed using an in vitro transwell assay. Next, we investigated the relationship between the reduction in macrophages in AS plaques and cytokine levels or foam cell formation. The results show that T0901317 reduced the number of high cholesterol-induced M1 macrophages by converting them into M2 macrophages in vivo and in vitro. Due to this phenotypic transition of macrophages, the inflammatory response was alleviated, and lipid metabolism was enhanced in AS plaques. This effect was achieved by promoting the expression of reverse transporters (ATP-binding cassette transporter member 1 and ATP-binding cassette subfamily G member 1) and inhibiting the phosphorylation of nuclear factor-κB-mediated phosphorylation.
RÉSUMÉ
OBJECTIVE: To evaluate the efficacy of Shoushen granule, prepared with four Chinese medicinals, on the targeted regulation of adenosine triphosphate binding cassette transporter A1 (ABCA1) through proprotein convertase subtilisin/kexin type 9 (PCSK9) and toll-like receptor 4 (TLR4) / nuclear factor kappa-B (NF-κB) signaling pathway to affect atherosclerosis (AS) in ApoE-knockout (ApoE-/-) mice. METHODS: ApoE-/- mice fed with a high-fat diet were used for AS modeling and divided into Model, Shoushen, and Atorvastatin groups. C57BL/6J mice at the same age and background strain were included in the Control group. Western blot and immunohistochemistry were used to measure ABCA1, PCSK9, TLR4, and NF-κB protein expression in mouse aortas. Enzyme-linked immuno sorbent assay was used to measure mouse serum tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), monocyte chemoattractant protein 1 (MCP-1), and intercellular cell adhesion molecule-1 (ICAM-1) expression. Serum lipid profiles and histopathology were also assessed. Shoushen granule were composed of Heshouwu (Radix Polygoni Multiflori) 15 g, Gouqizi (Fructus Lycii) 15 g, Sheng shanzha (Raw Fructus Crataegus Pinnatifidae) 10 g, and Sanqi (Radix Notoginseng) 3 g. RESULTS: ApoE-/- mice fed with a high-fat diet had notable AS lesions, with reduced ABCA1 and IL-10 levels, elevated PCSK9, TLR4, NF-κB, TNF-α, MCP-1, and ICAM-1 expression, and increased total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) contents. With drug interventions, the areas of AS plaques were significantly reduced, the ABCA1 and IL-10 levels were increase, while the PCSK9, TLR4, NF-κB, TC, and LDL-C contents, and the TNF-α, MCP-1, and ICAM-1 expression were reduced. CONCLUSION: Shoushen granule effectively interfered with AS development by antagonizing the expression of key factors of the PCSK9 and TLR4/NF-κB signaling pathway to upregulate ABCA1 expression.
Sujet(s)
Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP/métabolisme , Athérosclérose/traitement médicamenteux , Médicaments issus de plantes chinoises/administration et posologie , Facteur de transcription NF-kappa B/métabolisme , Proprotéine convertase 9/métabolisme , Subtilisine/métabolisme , Récepteur de type Toll-4/métabolisme , Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP/génétique , Animaux , Apolipoprotéines E/génétique , Apolipoprotéines E/métabolisme , Athérosclérose/génétique , Athérosclérose/métabolisme , Humains , Mâle , Souris , Souris de lignée C57BL , Souris knockout , Souris invalidées pour les gènes ApoE , Facteur de transcription NF-kappa B/génétique , Proprotéine convertase 9/génétique , Transduction du signal/effets des médicaments et des substances chimiques , Subtilisine/génétique , Récepteur de type Toll-4/génétiqueRÉSUMÉ
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.
Sujet(s)
Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP/biosynthèse , Lipoprotéines LDL/métabolisme , Récepteurs hépatiques X/biosynthèse , Macrophages/métabolisme , Proprotéine convertase 9/biosynthèse , Quercétine/pharmacologie , Régulation positive/effets des médicaments et des substances chimiques , Animaux , Inhibiteur p16 de kinase cycline-dépendante/biosynthèse , Inhibiteur p21 de kinase cycline-dépendante/biosynthèse , Macrophages/anatomopathologie , Souris , Cellules RAW 264.7 , Protéine p53 suppresseur de tumeur/biosynthèseRÉSUMÉ
Shen-Zhi-Ling (SZL) oral liquid is a traditional Chinese medicine formula that is mainly used for the clinical treatment of mild to moderate Alzheimer's disease (AD). The aim of the present study was to investigate the effects and underlying mechanisms of SZL treatment on AD. APP/PS1 transgenic mice were utilized to evaluate the effect of SZL treatment (0.5 g/20 g/day). Morris water maze and Thioflavin S staining analyses were used to evaluate the cognitive impairment and ß-amyloid plaques, respectively, while quantitative polymerase chain reaction and western blot analysis were performed to examine the mRNA and protein expression levels of heme oxygenase 1 (HO-1) and biliverdin reductase (BVR). Furthermore, immunofluorescence staining was used to measure the BVR and HO-1 protein levels in the hippocampus. The findings of the current study demonstrated that SZL treatment was able to ameliorate the impairment of memory and reduce the accumulation of amyloid plaques, and its ameliorating effects may be attributed to the modulation of the HO-1/BVR system in the hippocampus. These results indicate that SZL may be a possible complementary and alternative therapy to delay the development of AD.
RÉSUMÉ
BACKGROUND: Previous studies have reported the relation between the adiponectin polymorphisms and the risk of ischemic stroke. However, the findings is inclusive. In the present study, we performed a meta-analysis to clarify the relation between the adiponectin polymorphisms and the stroke. METHODS: Relevant studies were identified by searching PubMed, EMBASE, ISI Web of Science, ScienceDirect, Wiley Online Library, Wanfang database in China, and Chinese National Knowledge Infrastructure databases (CNKI) through July 2013 and other method such as reviewing the reference of retrieved literatures. We selected literatures that reported Odds ratio (OR) and 95% confidence interval (CI) for the relation between the ischemic stroke and the adiponectin genetic polymorphisms. With 1720 stroke cases and 5549 controls, were included. Our results showed that rs2241766 was associated with the risk of ischemic stroke in a recessive model (GG vs (TT+TG), OR = 1.29, 95% CI: 1.01-1.64, p = 0.04). However, rs1501299 and rs266729 were not found to be associated with ischemic stroke in our analysis. CONCLUSION: The present study suggested that rs2241766 polymorphism of adiponectin gene was associated with the risk for ischemic stroke.