This study aims to explore the effect of Buyang Huanwu Decoction glycosides on the inflammatory response of apolipoprotein E~(-/-)(ApoE~(-/-)) mice and RAW264.7 cells through nuclear factor kappa-B(NF-κB) signaling pathway. In the in vivo experiment, ApoE~(-/-) mice were fed with high-fat diets for 12 weeks to induce the animal model of atherosclerosis, and 75 μg·mL~(-1) oxidized low-density lipoprotein(Ox-LDL) incubated RAW264.7 cells for 24 h to establish the atherosclerosis cell model. Automatic biochemical analyzer, hematoxylin-eosin(HE) staining, enzyme-linked immunosorbent assay(ELISA), Western blot, and droplet digital polymerase chain reaction(PCR) were used to determine the blood lipid levels, aortic intimal thickness, inflammatory factor content, NF-κB pathway-related proteins, and mRNA expression levels, and evaluate arterial atherosclerotic lesions and anti-atherosclerotic mechanisms of the drug. The model of atherosclerosis was successfully established in ApoE~(-/-) mice after 12 weeks of feeding with high-fat diets. In the model group, the plasma levels of total cholesterol(TC), triglyceride(TG), and low-density lipoprotein cholesterol(LDL-C) were increased(P<0.01), the intima of the blood vessels was thickened, the levels of inflammatory factors tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) were increased, and the protein and mRNA expressions of NF-κB and inhibitor of NF-κB(IκBα) were significantly increased as compared with the control group. Compared with the model group, the high-dose Buyang Huanwu Decoction glycoside group decreased the plasma levels of TC, TG, and LDL-C, reduced the plaque area and thickness and the content of inflammatory factor TNF-α, and inhibited the protein and mRNA expressions of NF-κB and IκBα, with the effect same as Buyang Huanwu Decoction. In the in vivo experiment, 75 μg·mL~(-1) Ox-LDL stimulated RAW264.7 cells for 24 h to successfully establish a foam cell model. As compared with the control group, the nuclear amount of NF-κB and the protein and mRNA expressions of IκBα in the model group increased. Compared with the model group, the middle-dose and high-dose Buyang Huanwu Decoction glycoside groups decreased the nuclear amount of NF-κB and the protein and mRNA expressions of IκBα. The above results show that the glycosides are the main effective substances of Buyang Huanwu Decoction against atherosclerosis, which inhibit the NF-κB pathway and reduce the inflammatory response, thus playing the role against atherosclerotic inflammation same as Buyang Huanwu Decoction.
Mice ; Animals ; NF-kappa B/metabolism* ; NF-KappaB Inhibitor alpha/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Glycosides/pharmacology* ; Cholesterol, LDL ; Atherosclerosis/genetics* ; Signal Transduction ; Inflammation/drug therapy* ; Interleukin-6 ; Apolipoproteins E/pharmacology* ; RNA, Messenger/metabolism*

OBJECTIVE: To study the role of apolipoprotein E (APOE) in regulating endometrial cancer metastasis and explore the signaling pathway in the regulatory mechanism. METHODS: Human endometrial cancer cell line HEC-1B was transfected with a control siRNA (siCtrl) or a specific siRNA targeting APOE (siAPOE) or with either pEGFP-N1 plasmid or an APOEoverexpressing plasmid. The changes in migration, proliferation, apoptosis and cell cycle of the transfected cells were examined using wound healing assay, Transwell migration assay, MTT assay, flow cytometry, and Hoechst staining. The activity of the ERK/MMP9 signaling pathway in the transfected cells was assessed using RT-qPCR and Western blotting. The expression level of APOE in clinical specimens of endometrial cancer tissues were detected using immunohistochemistry and its correlation with differentiation of endometrial cancer tissues was analyzed. RESULTS: Wound healing assay and Transwell migration assay showed that compared with those in siCtrl group, HEC-1B cells transfected with siAPOE showed significantly reduced migration ability (P < 0.05), whereas APOE overexpression significantly promoted the migration of the cells (P < 0.05). Neither APOE knockdown nor overexpression produced significant effects on HEC-1B cell proliferation as shown by MTT assay and flow cytometry. Hoechst staining revealed that transfection with siAPOE did not significantly affect apoptosis of HEC-1B cells. APOE knockdown obviously reduced and APOE overexpression enhanced ERK phosphorylation and MMP9 expression in HEC-1B cells (P < 0.05). Treatment with U0126 partially reversed the effects of APOE overexpression on ERK phosphorylation, migration and MMP9 expression in HEC-1B cells (P < 0.05). APOE is highly expressed in clinical samples of endometrial cancer tissues as compared with the adjacent tissues. CONCLUSION APOE is highly expressed in endometrial cancer tissues to promote cancer cell migration by enhancing ERK phosphorylation and MMP9 expression.
Female ; Humans ; Matrix Metalloproteinase 9/metabolism* ; Cell Line, Tumor ; Signal Transduction ; Endometrial Neoplasms/genetics* ; Cell Proliferation ; Apoptosis ; Cell Movement ; RNA, Small Interfering ; Apolipoproteins E ; Apolipoproteins/pharmacology*

This study was designed to evaluate the role of short-chain fatty acid butyrate acid on intestinal morphology and function, and atherosclerotic plaque formation in apolipoprotein E-knockout (ApoE
Animals ; Apolipoproteins E/genetics* ; Atherosclerosis/prevention & control* ; Butyrates/pharmacology* ; Caco-2 Cells ; Diet, High-Fat/adverse effects* ; Fatty Acids, Volatile ; Humans ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Plaque, Atherosclerotic

Objective To investigate the role of proteasome inhibitor bortezomib (BTZ) in inflammatory response in abdominal aortic aneurysm (AAA) formation induced by angiotensin Ⅱ (Ang Ⅱ). Methods Ang Ⅱ-induced ApoEmice AAA models were established. Forty male ApoEmice (8-10-week-old) were randomly and equally divided into four groups:Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group.HE staining,immunohistochemical staining,and flow cytometry were used to analyze the inflammatory response. Real-time quantitative polymerase chain reaction (qPCR) was used to analyze the mRNA expression of intercellular cell adhesion molecule-1 (ICAM-1). Western blotting was used to analyze the activation of nuclear factor κB signaling (NF-κB). Results The mean maximum suprarenal aortic diameter (Dmax) of Sham group,BTZ group,Ang Ⅱ group,and Ang Ⅱ+BTZ group were (1.00±0.01),(0.99±0.01),(1.50±0.13),and (1.20±0.04)mm,respectively (F=8.959,P=0.000). The Dmax of Ang Ⅱ group was significantly larger than those of Sham group (P=0.000) and Ang Ⅱ+BTZ group (P=0.015). The incidence of AAA in Ang Ⅱ group,Ang Ⅱ+BTZ group,and Sham group were 60%,17%,and 0,respectively. HE staining revealed that the abdominal aortic wall thickening was more severe in Ang Ⅱ group than in Sham group and Ang Ⅱ+BTZ group,similar with the infiltration of inflammatory cells. Immunohistochemical staining demonstrated that the CD3T lymphocyte count was significantly higher in Ang Ⅱ group than in Sham group (107.9±15.9 vs. 0,P=0.000) and Ang Ⅱ+BTZ group (107.9±15.9 vs. 0.8±0.5,P=0.000). Flow cytometry also demonstrated that the proportion of the CD3T lymphocytes of the Ang Ⅱ group [(13.50±0.69)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(10.40±0.78)%] at week 1 (t=3.009,P=0.040),and the proportion of the CD3T lymphocytes of the Ang Ⅱ group [(22.70±0.93)%] was significantly higher than that in the Ang Ⅱ+BTZ group [(15.10±0.97)%] at week 4 (t=5.654,P=0.005). The qPCR analysis showed that the mRNA expression of ICAM-1 was significantly up-regulated in Ang Ⅱ group than in Sham group (1.93±0.54 vs. 1.00±0.15,P=0.011) and Ang Ⅱ+BTZ group (1.93±0.54 vs. 0.83±0.08,P=0.009). Western blot analysis showed a lower phosphorylation level of inhibitor of NF-κB in the Ang Ⅱ group compared with the Sham group or Ang Ⅱ+BTZ group,accompanied with an increased phosphorylation level of p65. Conclusion Proteasome inhibitor BTZ can attenuate AAA formation partially by regulating T lymphocytes infiltration through regulating the mRNA expression of ICAM-1 regulated by the activation of NF-κB signaling pathway.
Angiotensin II ; adverse effects ; Animals ; Aortic Aneurysm, Abdominal ; chemically induced ; drug therapy ; Apolipoproteins E ; genetics ; Bortezomib ; pharmacology ; Intercellular Adhesion Molecule-1 ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; NF-kappa B ; metabolism ; Phosphorylation ; Proteasome Inhibitors ; pharmacology ; Random Allocation ; Signal Transduction ; T-Lymphocytes ; cytology

OBJECTIVETo investigate the effects of the DPP4 inhibitor sitagliptin on the expressions of early growth response-1 (Egr-1) and fibronectin in the kidney of ApoE gene knockout mice.

METHODSEight-week-old male ApoE gene knockout mice were randomly divided into sitagliptin + apoE(-/-) group and apoE(-/-) group (n=6), with 6 C57BL mice as the normal control group. After feeding with high-fat diet and drug treatment for 16 weeks, the mice underwent intraperitoneal glucose tolerance test (IPGTT) and were measured for 24-h urinary albumin using ELISA. All the mice were then sacrificed to examine the changes of blood lipid profile and for detection of Egr-1 and fibronectin mRNA and proteins in the renal tissue using real-time PCR and Western blotting.

RESULTSThe mice in both apoE(-/-) group and sitagliptin+apoE(-/-) group all showed prominently increased blood lipids as compared with the control group (P<0.05) without significant differences between the two apoE(-/-) groups. The level of HDL was significantly higher in sitagliptin +apoE(-/-) group than in apoE(-/-) group (P<0.001) and control group (P<0.001). IPGTT showed no significant differences in the levels of blood glucose among the 3 groups. The excretion of urinary albumin was increased in apoE(-/-) group compared with the control group (P<0.01), but was significantly lower in sitagliptin+ apoE(-/-) group than in apoE(-/-) group (P<0.01). Real-time PCR and Western blotting showed significantly decreased mRNA and protein expressions of renal cortical Egr-1 and fibronectin in sitagliptin+apoE(-/-) group compared with apoE(-/-) group.

CONCLUSIONSitagliptin can reduce the renal expression of fibronectin by regulating the expression of Egr-1 to achieve renal protection.

Animals ; Apolipoproteins E ; genetics ; Diet, High-Fat ; Dipeptidyl-Peptidase IV Inhibitors ; pharmacology ; Early Growth Response Protein 1 ; metabolism ; Fibronectins ; metabolism ; Gene Knockout Techniques ; Kidney ; metabolism ; Lipids ; blood ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Real-Time Polymerase Chain Reaction ; Sitagliptin Phosphate ; pharmacology

OBJECTIVETo observe monocyte (Mo) development in wild type C57BL/6 mice and apoE gene knockout (apoE(-/-)) mice, and to evaluate the immuno-regulatory effect of Huanglian Jiedu Decoction (HJD) on peripheral Mo development in apoE(-/-) mice.

METHODSFour, 8, 12, and 16 weeks old female C57BL/6 mice were set up as control groups of different ages, while 4, 8, 12, and 16 weeks old female apoE(-/-) mice were set up as hyperlipidemia groups of different ages. Four-week old female C57BL/6 mice were recruited as a blank group. Four-week old female apoE(-/-) mice were randomly divided into the control group, the Western medicine group, and the Chinese medicine group by paired comparison, 5 in each group. Equivalent clinical dose was administered to mice according to body weight. Mice in the Western medicine group were administered with Atrovastatin at the daily dose of 10 mg/kg by gastrogavage, while those in the Chinese medicine group were administered with HJD at the daily dose of 5 g/kg by gastrogavage. Body weight was detected each week. After 4 weeks blood lipids levels (such as TG, TC, LDL-C, and HDL-C), and the proportions of Mo and Ly6c(hi) were detected.

RESULTSCompared with 4-week-old homogenic mice, the proportion of Mo decreased in 16-week-old C57BL/6 mice (P < 0.05). Levels of TC and TG, and the proportion of Ly6c(hi) subtype increased, but the proportion of Mo de- creased in 8-week-old apoE(-/-) mice (P <0. 05). Levels of TC, TG, and LDL-C increased in 12-week-old apoE(-/-) mice (P < 0.05). Levels of TC, TG, LDL-C, and HDL-C increased in 16-week-old apoE(-/-) mice (P < 0.05, P < 0.01). Compared with 8-week-old homogenic mice, the proportion of Mo decreased in 16-week-old C57BL/6 mice (P < 0.05); levels of TC and LDL-C increased in 12-week-old apoE(-/-) mice (P < 0.05); levels of TC and HDL-C increased in 16-week-old apoE(-/-) mice (P < 0.05, P < 0.01). Compared with C57BL/6 mice of the same age, TC and TG increased, HDL-C decreased (P < 0.01) in 4-and 8-week-old apoE(-/-) mice (P < 0.01); levels of TC, TG, LDL-C increased, and HDL-C level decreased in 12- and 16-week-old apoE(-/-) mice (P < 0.05, P < 0.01); the proportion of Mo increased in 4-week-old apoE(-/-) mice (P < 0.05); proportions of Mo and Ly6c(hi) increased in 8-week-old apoE(-/-) mice (P < 0.05). Compared with the blank control group, levels of TC, TG, and LDL-C, proportions of Mo and Ly6c(hi) increased (P < 0.01, P < 0.05), but HDL-C level decreased (P <0. 01) in the control group after intervention. Compared with the control group, body weight gained less in the Western medicine group and the Chinese medicine group (P < 0.05); the proportion of Ly6c(hi) subtype decreased in the Chinese medicine group (P < 0.05).

CONCLUSIONSIn development process blood lipids levels in apoE(-/-) mice are not only associated with age. Blood lipids levels induced growth changes in natural immune system are also correlated with age. In early stage of lipids development HJD intervention could correct this special immune disorder in apoE(-/-) mice.

Animals ; Apolipoproteins E ; genetics ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Gene Knockout Techniques ; Hyperlipidemias ; Lipids ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Monocytes ; physiology

OBJECTIVETo study the effect of polydatin on the expression level of miR-214 and liver function in atherosclerotic mice.

METHODSForty male ApoE(-/-) mice were randomly allocated into 4 groups (n=10), namely the model group, low- and high-dose polydatin groups, and simvastin group, with 10 male C57BL/6J mice serving as the normal control group. Mouse models of atherosclerosis were established by feeding the ApoE(-/-) mice with a high-fat diet. After 12 weeks of treatment, blood levels of glucose, lipids, AST, and ALT and the contents of T-SOD and MDA in the liver tissue were detected. The pathologies of the liver were examined with HE staining, and miR-214 expression in the liver was detected using quantitative real-time PCR.

RESULTSCompared with the normal control mice, the mice in the model group showed significantly increased blood glucose, serum TC, TG, LDL-C, ALT, and AST levels, and MDA contents in the liver (P<0.01), with significantly decreased serum HDL-C level and SOD and miR-214 levels in liver (P<0.01). Polydatin treatment significantly ameliorated such changes in blood glucose, serum ALT, AST, TC, TG, LDL-C, and HDL-C levels, and MDA, SOD, and miR-214 contents in liver tissue (P<0.05).

CONCLUSIONs Polydatin can reduce blood glucose and lipid levels and protect the liver function in atherosclerotic mice possibly by up-regulating the expression of miR-214 and T-SOD and down-regulating MDA in the liver.

Animals ; Apolipoproteins E ; genetics ; Atherosclerosis ; drug therapy ; Blood Glucose ; analysis ; Diet, High-Fat ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Glucosides ; pharmacology ; Lipids ; blood ; Liver ; drug effects ; Male ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; MicroRNAs ; metabolism ; Stilbenes ; pharmacology ; Superoxide Dismutase ; metabolism

OBJECTIVETo investigate the pathologies of aortic root atherosclerotic lesion in uremic apoE-/- mice and explore the effect of serum from patients with chronic renal insufficiency (CRI) and the uremic toxin, indoxyl sulfate (IS), on the expression of cholesterol transporting receptors and lipid accumulation in macrophages in vitro.

METHODSThe uremic apoE-/- mouse model was established by surgical operation. Frozen sections of the aortic root were collected from uremic apoE-/- mice, sham-operated apoE-/- mice and C57BL/6J mice and stained with oil red O to calculate the relative area of atherosclerotic plaque. Murine macrophage RAW264.7 cell line was treated for 12 h with different concentrations of IS or serum samples from CRI patients and healthy individuals, and the mRNA expressions of cholesterol transporting receptors (SR-A1, CD36, ABCA1, ABCG1 and SR-B1) were detected. After treatment for 24 h, the cells were induced into foam cells to determine lipid contents using oil red O staining.

RESULTSThe relative area of the atherosclerotic plaques in the aortic root increased significantly in uremic apoE-/- mice compared with that in sham-operated apoE-/- mice. CRI serum (5%) and IS (250 µmol/L) obviously increased the mRNA expression of CD36 and lipid accumulation in the macrophages, but did not affect the mRNA expression of other cholesterol transporting receptors.

CONCLUSIONCRI can accelerate the progression of atherosclerosis through the mechanism that IS in CRI serum promotes lipid accumulation in macrophages by enhancing the mRNA expression of CD36, which contributes to the formation of foam cells.

Animals ; Apolipoproteins E ; Cell Line ; Foam Cells ; chemistry ; Humans ; Indican ; pharmacology ; Lipids ; chemistry ; Macrophages ; chemistry ; Mice ; Mice, Inbred C57BL ; Plaque, Atherosclerotic ; pathology ; Renal Insufficiency, Chronic ; blood

UNLABELLEDOBJECTIVE : To study the anti-atherosclerotic mechanism of bear bile powder (BBP) in Shexiang Tongxin Dripping Pill (STDP) , and to provide scientific evidence for treating atherosclerosis (AS) by its therapeutic characteristics of cool resuscitation.

METHODSAS model was duplicated using ApoE-/- gene knocked mice fed with high-fat diet. Thirty ApoE-/- deficient male mice were divided into four groups according to body weight using random digit table, i.e., the model group (A, n =9), the STDP group (B, n=E7), the STDP without BBP group (C, n =7), and the BBP group (D, n =9). Besides, another 9 C57BL/6J male mice of the same age were recruited as a normal control group (E). All mice in Group B, C, and D were respectively administered with corresponding drugs (30, 30, and 0. 33 mg/kg) by gastrogavage. Equal volume of normal saline was administered to mice in Group A and E. All medication lasted for 8 successive weeks. Serum levels of inflammatory cytokines such as interleukin 2 (IL-2), interleukin 6 (IL-6), tumor necrosis factor a (TNF-α), interferon y (IFNγ), and oxidized low-density lipoprotein (ox-LDL) were measured by ELISA. Serum levels of malondialdehyde (MDA), activities of glutathione (GSH) and superoxide dismutase (SOD) were determined using biochemical assay. Contents of reactive oxygen species (ROS) in the aortic root was detected by dihydroethidum (DHE) fluorescent probe. Expression levels of microRNAs (such as miR-20, miR-21, miR-126, and miR-155) were detected by real-time PCR.

RESULTSThe fluorescence intensity of the aorta was obviously enhanced in Group A. But it was obviously attenuated in Group B, C, and D, and the attenuation was the most in Group B. Compared with Group E, serum levels of IL-2, IL-6, TNF-α, IFN-γ, oxLDL, and MDA all increased (P <0. 01), GSH contents and SOD activities decreased (P <0. 01), expression levels of miR-126, miR-21, and miR-155 in aorta increased (P <0. 01), and the expression level of miR-20 decreased in Group A (P<0. 01). Compared with Group A, serum levels of IL-2, IL-6, TNF-α, IFN-γ, oxLDL, and MDA were all down-regulated (P <0. 01), GSH contents and SOD activities were up-regulated (P <0. 01), expression levels of miR-126, miR-21, and miR-155 in aorta were down-regulated in Group B, C, and D (P <0. 01). The expression level of miR20 was up-regulated in Group B and D (P <0. 01). Compared with Group B, serum levels of IL-2, IL-6, TNF-α, IFN-γ increased (P <0.01); GSH contents and SOD activities decreased, levels of MDA and oxLDL increased (P <0. 01) in Group C and D. Expression levels of miR-20 and miR-155 were down-regulated in Group C and D (P <0. 01).

CONCLUSIONSSTDP played roles in significantly regulating inflammatory factors and oxidative stress factors. Its mechanism might be possibly associated with regulating expressions of miR-126, miR-21, miR-155, and miR-20 in aorta. BBP played significant roles in STDP.

Animals ; Aorta ; Apolipoproteins E ; metabolism ; Atherosclerosis ; Bile ; Cytokines ; Diet, High-Fat ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; therapeutic use ; Interleukin-6 ; metabolism ; Lipoproteins, LDL ; metabolism ; Male ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred C57BL ; Oxidative Stress ; Plaque, Atherosclerotic ; drug therapy ; Reactive Oxygen Species ; Superoxide Dismutase ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism ; Ursidae

OBJECTIVETo investigate the effect and molecular mechanisms of different doses of 8-hydroxy dihydroberberine (Hdber) for the treatment of hyperlipidemia in rats.

METHODSA rat model of hyperlipidemia was established by feeding rats a high-fat diet for 4 weeks in 70 rats of 80 animals, and 10 rats were randomly selected as control group. The hyperlipidemic rats were then randomly divided into the following groups: a model group (MOD); a berberine group [BBR, 156 mg/(kg day)]; Hdber groups, which were treated with different doses of Hdber [78, 39 and 19.5 mg/(kg day)]; and a simvastatin group [SIM, 4 mg/(kg day)]. The corresponding therapy was administered to the rats of each treatment via gastric tubes. Normal animals were used as a control group. The blood levels of various lipids, including total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, free fatty acid (FFA), apolipoprotein AI(Apo-AI) and apolipoprotein B (Apo-B) were examined. The protein expressions of low-density lipoprotein receptor (LDL-R), sterol regulatory element-binding protein 2 (SREBP-2), 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) and proprotein convertase subtilisin/kexin type 9 (PCSK-9) in liver tissues were determined by Western blot analysis.

RESULTSCompared with the control group of rats, the model group demonstrated a deteriorated blood lipid profile and exhibited increased expression levels of PCSK-9 protein in their liver tissues (P<0.01). In addition, the high-fat diet decreased the expression levels of LDL-R, SREBP-2 and HMGCR proteins in murine liver tissues. However, the addition of berberine or Hdber reversed the blood lipid profile changes (P<0.05 or P<0.01), decreased the expression levels of PCSK-9 proteins (P<0.01), and increased the expression levels of LDL-R proteins in the hyperlipidemic rats (P<0.01). These compounds did not significantly influence the expression levels of SREBP-2 and HMGCR proteins in the hyperlipidemic rats.

CONCLUSIONSHdber is effective in the treatment of hyperlipidemia in rats. The therapeutic mechanisms of Hdber may be associated with increasing the expression of LDL-R protein and decreasing the expression of PCSK-9 protein in liver tissues.

Animals ; Apolipoprotein A-I ; blood ; Apolipoproteins B ; blood ; Berberine ; analogs & derivatives ; pharmacology ; therapeutic use ; Hydroxymethylglutaryl CoA Reductases ; metabolism ; Hyperlipidemias ; blood ; drug therapy ; Lipids ; blood ; Liver ; drug effects ; metabolism ; Male ; Proprotein Convertase 9 ; Rats, Wistar ; Receptors, LDL ; metabolism ; Serine Endopeptidases ; metabolism ; Sterol Regulatory Element Binding Protein 2 ; metabolism