Association of anti-obesity activity of N-acetylcysteine with metallothionein-II down-regulation

People with upper body or visceral obesity have a much higher risk of morbidity and mortality from obesity-related metabolic disorders than those with lower body obesity. In an attempt to develop therapeutic strategies targeting visceral obesity, depot- specific differences in the expression of genes in omental and subcutaneous adipose tissues were investigated by DNA array technology, and their roles in adipocyte differentiation were further examined. We found that levels of metallothionein-II (MT-II) mRNA and protein expression were higher in omental than in subcutaneous adipose tissues. The study demonstrates that MT-II may play an important role in adipocyte differentiation of 3T3L1 preadipocytes, and that N-acetylcysteine (NAC) inhibits the adipocyte differentiation of 3T3L1 cells by repressing MT-II in a time- and dose-dependent manner. Furthermore, the intraperitoneal administration of NAC to rats and mice resulted in a reduction of body weights, and a marked reduction in visceral fat tissues. These results suggest that MT-II plays important roles in adipogenesis, and that NAC may be useful as an anti-obesity drug or supplement.     

Fenofibrate regulates obesity and lipid metabolism with sexual dimorphism

To determine whether the PPARalpha agonist fenofibrate regulates obesity and lipid metabolism with sexual dimorphism, we examined the effects of fenofibrate on body weight, white adipose tissue (WAT) mass, circulating lipids, and the expression of PPARalpha target genes in both sexes of high fat diet-fed C57BL/6J mice. Both sexes of mice fed a high-fat diet for 14 weeks exhibited increases in body weight, visceral WAT mass, as well as serum triglycerides and cholesterol, although these effects were more pronounced among males. Feeding a high fat diet supplemented with fenofibrate (0.05% w/w) reduced all of these effects significantly in males except serum cholesterol level. Females on a fenofibrate-enriched high fat diet had reduced serum triglyceride levels, albeit to a smaller extent compared to males, but did not exhibit decreases in body weight, WAT mass, and serum cholesterol. Fenofibrate treatment resulted in hepatic induction of PPARalpha target genes encoding enzymes for fatty acid beta-oxidation, the magnitudes of which were much higher in males compared to females, as evidenced by results for acyl-CoA oxidase, a first enzyme of the beta-oxidation system. These results suggest that observed sexually dimorphic effects on body weight, WAT mass and serum lipids by fenofibrate may involve sexually related elements in the differential activation of PPARalpha.     

BAFF knockout improves systemic inflammation via regulating adipose tissue distribution in high-fat diet-induced obesity

Obesity is recognized as a chronic low-grade inflammatory state due to adipose tissue expansion being accompanied by an increase in the production of proinflammatory adipokines. Our group is the first to report that B-cell-activating factor (BAFF) is produced from adipocytes and functions as a proinflammatory adipokine. Here, we investigated how loss of BAFF influenced diet-induced obesity in mice by challenging BAFF^−/− mice with a high-fat diet for 10 weeks. The results demonstrated that weight gain in BAFF^−/− mice was >30% than in control mice, with a specific increase in the fat mass of the subcutaneous region rather than the abdominal region. Expression of lipogenic genes was examined by quantitative real-time PCR, and increased lipogenesis was observed in the subcutaneous adipose tissue (SAT), whereas lipogenesis in the epididymal adipose tissue (EAT) was reduced. A significant decrease in EAT mass resulted in the downregulation of inflammatory gene expression in EAT, and more importantly, overall levels of inflammatory cytokines in the circulation were reduced in obese BAFF^−/− mice. We also observed that the macrophages recruited in the enlarged SAT were predominantly M2 macrophages. 3T3-L1 adipocytes were cultured with adipose tissue conditioned media (ATCM), demonstrating that EAT ATCM from BAFF^−/− mice contains antilipogenic and anti-inflammatory properties. Taken together, BAFF^−/− improved systemic inflammation by redistributing adipose tissue into subcutaneous regions. Understanding the mechanisms by which BAFF regulates obesity in a tissue-specific manner would provide therapeutic opportunities to target obesity-related chronic diseases.     

Fenofibrate inhibits adipocyte hypertrophy and insulin resistance by activating adipose PPAR�� in high fat diet-induced obese mice

Peroxisome proliferator-activated receptor α (PPARα) activation in rodents is thought to improve insulin sensitivity by decreasing ectopic lipids in non-adipose tissues. Fenofibrate, a lipid-modifying agent that acts as a PPARα agonist, may prevent adipocyte hypertrophy and insulin resistance by increasing intracellular lipolysis from adipose tissue. Consistent with this hypothesis, fenofibrate decreased visceral fat mass and adipocyte size in high fat diet-fed obese mice, and concomitantly increased the expression of PPARα target genes involved in fatty acid β-oxidation in both epididymal adipose tissue and differentiated 3T3-L1 adipocytes. However, mRNA levels of adipose marker genes, such as leptin and TNFα, were decreased in epididymal adipose tissue by fenofibrate treatment. Fenofibrate not only reduced circulating levels of free fatty acids and triglycerides, but also normalized hyperinsulinemia and hyperglycemia in obese mice. Blood glucose levels of fenofibrate-treated mice were significantly reduced during intraperitoneal glucose tolerance test compared with obese controls. These results suggest that fenofibrate-induced fatty acid β-oxidation in visceral adipose tissue may be one of the major factors leading to decreased adipocyte size and improved insulin sensitivity.     

Application of bispecific antibody against antigen and hapten for immunodetection and immunopurification

We present a bispecific antibody that recognizes an antigen and a hapten and can be applied to various biological assays, including immunoblotting and immunoprecipitation. In immunoblot analysis of serum, an anti-C5 × anti-cotinine bispecific tandem single-chain variable fragment (scFv)-Fc fusion protein and cotinine-conjugated horseradish peroxidase (HRP) generated a clean signal without the high background that was observed in a parallel experiment using HRP-conjugated goat anti-rabbit immunoglobulin G (Fc-specific) antibody. In immunoprecipitation analysis of serum, use of the bispecific tandem scFv-Fc fusion protein and cotinine-crosslinked magnetic beads significantly reduced the amount of protein contaminants compared with a parallel experiment done with protein A agarose beads. In subsequent immunoblot analysis, use of cotinine–HRP as the secondary probe instead of HRP-conjugated goat anti-rabbit IgG (Fc-specific) antibody successfully eliminated the band corresponding to the bispecific tandem scFv-Fc fusion protein.     

Hypolipidemic effects of hydrolyzed xyloglucan

Xyloglucan is found in the primary cell walls of higher plants, where it plays important biological roles. It also exists in certain seeds, for example tamarind, as a reserve polysaccharide. Some xyloglucan oligosaccharides possess plant growth promotion activity. We prepared hydrolyzed xyloglucan from the tamarind seed xyloglucan using endo-(1 → 4)- β -glucanase and examined its effects on lipid metabolism in rats fed a high fat diet. Among the plasma lipids, total lipid, cholesterol, triglyceride and β - lipoprotein were each reduced 14 - 17% by hydrolyzed xyloglucan. Hydrolyzed xyloglucan significantly reduced both adipose tissue weight and plasma GOT. Among the hepatic lipids, total lipid, cholesterol, triglyceride and phospholipid were significantly reduced by hydrolyzed xyloglucan. These hypolipidemic effects may be important for the treatment and prevention of geriatric diseases, including diabetes and cardiac disorders.     

有机铬改善SD大鼠体组成效果及其机制探讨

为探讨两种形式有机铬吡啶羧酸铬（CrPic）和烟酸铬（CrNic）改善SD大鼠体组成的效果及其机制,将60只雄性SD大鼠随机等分为3组,第1组饲喂基础日粮作为对照组,第2和第3组分别以CrPic和CrNic形式添加300μg/kg铬,自由采食和饮水,6周后测定大鼠体组成和皮下脂肪组织中脂肪酸合成酶及激素敏感酯酶活性以及血清相关指标。结果表明,添加CrPic使大鼠瘦体质量提高了21．9％（P〈0．05）,体脂含量降低了22．6％（P〈0．05）;添加CrNic对大鼠瘦体质量和体脂含量没有产生显著影响（P〉0．05）;CrPic使大鼠皮下脂肪组织中脂肪酸合成酶活性降低了5．6％（P〈0．05）,激素敏感酯酶活性提高了63．1％（P〈0．05）,同时,大鼠血清中葡萄糖和胰岛素水平显著降低;CrNic对皮下脂肪组织中脂肪酸合成酶、激素敏感酯酶活性以及血清相关指标没有产生显著影响（P〉0．05）。提示CrPic能通过减弱机体脂肪合成代谢,增强脂肪分解代谢从而提高大鼠瘦体质量,降低体脂含量,其效果显著高于CrNic。     

Anti-obesity effects of Lysimachia foenum-graecum characterized by decreased adipogenesis and regulated lipid metabolism

Lysimachia foenum-graecum has been used as an oriental medicine with anti-inflammatory effect. The anti-obesity effect of L. foenum-graecum extract (LFE) was first discovered in our screening of natural product extract library against adipogenesis. To characterize its anti-obesity effects and to evaluate its potential as an anti-obesity drug, we performed various obesity-related experiments in vitro and in vivo. In adipogenesis assay, LFE blocked the differentiation of 3T3-L1 preadipocyte in a dose-dependent manner with an IC50 of 2.5 μg/ml. In addition, LFE suppressed the expression of lipogenic genes, while increasing the expression of lipolytic genes in vitro at 10 μg/ml and in vivo at 100 mg/kg/day. The anti-adipogenic and anti-lipogenic effect of LFE seems to be mediated by the inhibition of PPARγ and C/EBPα expression as shown in in vitro and in vivo, and the suppression of PPARγ activity in vitro. Moreover, LFE stimulated fatty acid oxidation in an AMPK-dependent manner. In high-fat diet (HFD)-induced obese mice (n = 8/group), oral administration of LFE at 30, 100, and 300 mg/kg/day decreased total body weight gain significantly in all doses tested. No difference in food intake was observed between vehicle- and LFE-treated HFD mice. The weight of white adipose tissues including abdominal subcutaneous, epididymal, and perirenal adipose tissue was reduced markedly in LFE-treated HFD mice in a dose-dependent manner. Treatment of LFE also greatly improved serum levels of obesity-related biomarkers such as glucose, triglycerides, and adipocytokines leptin, adiponectin, and resistin. All together, these results showed anti-obesity effects of LFE on adipogenesis and lipid metabolism in vitro and in vivo and raised a possibility of developing LFE as anti-obesity therapeutics.     

Annexin A6 is highly abundant in monocytes of obese and type 2 diabetic individuals and is downregulated by adiponectin in vitro

Adiponectin stimulates cholesterol efflux in macrophages and low adiponectin may in part contribute to disturbed reverse cholesterol transport in type 2 diabetes. Monocytes express high levels of annexin A6 that could inhibit cholesterol efflux and it was investigated whether the atheroprotective effects of adiponectin are accompanied by changes in annexin A6 levels. Adiponectin reduces annexin A6 protein whereas mRNA levels are not affected. Adiponectin-mediated activation of peroxisome proliferator-activated receptor α (PPARα) and AMP-activated protein kinase (AMPK) does not account for reduced annexin A6 expression. Further, fatty acids and lipopolysaccharide that are elevated in obesity do not influence annexin A6 protein levels. Annexin A6 in monocytes from overweight probands or type 2 diabetic patients is significantly elevated compared to monocytes of normal-weight controls. Monocytic annexin A6 positively correlates with body mass index and negatively with systemic adiponectin of the blood donors. Therefore, the current study demonstrates that adiponectin reduces annexin A6 in monocytes and thereby may enhance cholesterol efflux. In agreement with these in vitro finding an increase of monocytic annexin A6 in type 2 diabetes monocytes was observed.     

Potential of <Emphasis Type="Italic">Crocus sativus</Emphasis> (saffron) and its Constituent,Crocin, as Hypolipidemic and Antioxidant in Rats

The aim of the present study was to evaluate the hypolipidemic and antioxidant potential of saffron and its active constituent, crocin, in hyperlipidemic rats. The animals fed either with normal fat diet or high fat diet were administered orally saffron (25, 50, and 100 mg/kg) or crocin (4.84, 9.69, and 19.38 mg/kg) in their respective groups for five consecutive days. Biochemical estimations of triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), alkaline phosphatase (ALP), aspartate transaminase (AST), alanine aminotransferase (ALT), malondialdehyde (MDA), glutathione peroxidase enzyme activity (GSHPx), total glutathione (GSH), and oxidized glutathione (GSSG) in serum and superoxide dismutase (SOD), catalase (CAT), thiobarbituric acid reactive species (TBARS), ferric reducing/antioxidant power (FRAP), and total sulfhydryl (SH) groups in liver tissue homogenate were carried out. Both saffron and crocin were effective in decreasing the elevated levels of TG, TC, ALP, AST, ALT, MDA, GSHPx, GSH, and GSSG in serum and increasing SOD, CAT, FRAP, and SH values in liver tissue with reduction in TBARS. The saffron was found to be superior to crocin indicating the involvement of other potential constituents of saffron apart from crocin for its synergistic behavior of quenching the free radicals and ameliorating the damages of hyperlipidemia.     

Evaluation of New Pharmaceuticals Using In Vivo Neutron Inelastic Scattering and Neutron Activation Analysis

Nutritional status of patients can be evaluated by monitoring changes in body composition, including depletion of protein and muscle, adipose tissue distribution and changes in hydration status, bone or cell mass. Fast neutron activation (for N and P) and neutron inelastic scattering (for C and O) are used to assess in vivo elements characteristic of specific body compartments. The fast neutrons are produced with a sealed deuterium-tritium (D-T) neutron generator. This method provides the most direct assessment of body composition. Non-bone phosphorus for muscle is measured by the ³¹P(n,)²⁸Al reaction, and nitrogen for protein via the (n,2n) fast neutron reaction. Inelastic neutron scattering is used for the measurement of total body carbon and oxygen. Carbon is used to derive body fat, after subtracting carbon contributions due to protein, bone and glycogen. Carbon-to-oxygen (C/O) ratio is used to measure distribution of fat and lean tissue in the body and to monitor small changes of lean mass and its quality. In addition to evaluating the efficacy of new treatments, the system is used to study the mechanisms of lean tissue depletion with aging and to investigate methods for preserving function and quality of life in the elderly.     

GC determination of nicotine in subcutaneous adipose tissue obtained by minimal trauma tissue biopsy

Summary Nicotine has been analyzed by gas chromatography nitrogen-phosphorus detection in tissue samples obtained by repeated minimal trauma tissue biopsies from human subcutaneous adipose tissue. For sample preparation, a single extraction step of the tissue samples with chloroform was performed at 30–45°C. Calibration curves generated with spiked porcine subcutaneous adipose tissue were linear over a concentration range from 0.20 to 100 μg g⁻¹, therefore, the limit of quantification was fixed at 0.20 μg g⁻¹. The limit of detection was found to be 0.05 μg g⁻¹ adipose tissue. The recovery of nicotinespiked porcine subcutaneous adipose tissue by chloroform extraction was 100±8%. The performance of the assay was not affected by the complex lipid matrix. The method was employed for analysis in a clinical study on nicotine penetration from a transdermal delivery system through the skin of moderate smokers. Presented at Balaton Symposium on High Performance Separation Methods, Siófok, Hungary, September 1–3, 1999.     

Improvement of Obesity and Dyslipidemic Activity of Amomum tsao-ko in C57BL/6 Mice Fed a High-Carbohydrate Diet

Amomum tsao-ko Crevost et Lemaire (Zingiberaceae) is a medicinal herb found in Southeast Asia that is used for the treatment of malaria, abdominal pain, dyspepsia, etc. The aim of this study was to investigate the effect of an ethanol extract of Amomum tsao-ko (EAT) on obesity and hyperlipidemia in C57BL/6 mice fed a high-carbohydrate diet (HCD). First, the mice were divided into five groups (n = 6/group) as follows: normal diet, HCD, and HCD+EAT (100, 200, and 400 mg/kg/day), which were orally administered with EAT daily for 84 days. Using microcomputed tomography (micro-CT) analysis, we found that EAT inhibited not only body-weight gain, but also visceral fat and subcutaneous fat accumulation. Histological analysis confirmed that EAT decreased the size of fat tissues. EAT consistently improved various indices, including plasma levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein, high-density lipoprotein, atherogenic index, and cardiac risk factors, which are related to dyslipidemia—a major risk factor for heart disease. The contents of TC and TG, as well as the lipid droplets of HCD-induced hepatic accumulation in the liver tissue, were suppressed by EAT. Taken together, these findings suggest the possibility of developing EAT as a therapeutic agent for improving HCD-induced obesity and hyperlipidemia.     

Methanolic Extract of Piper sarmentosum Attenuates Obesity and Hyperlipidemia in Fructose-Induced Metabolic Syndrome Rats

Obesity and hyperlipidemia are metabolic dysregulations that arise from poor lifestyle and unhealthy dietary intakes. These co-morbidity conditions are risk factors for vascular diseases. Piper sarmentosum (PS) is a nutritious plant that has been shown to pose various phytochemicals and pharmacological actions. This study aimed to investigate the effect of PS on obesity and hyperlipidemia in an animal model. Forty male Wistar rats were randomly divided into five experimental groups. The groups were as follows: UG—Untreated group; CTRL—control; FDW—olive oil + 20% fructose; FDW-PS—PS (125 mg/kg) + 20% fructose; FDW-NGN—naringin (100 mg/kg) + 20% fructose. Fructose drinking water was administered daily for 12 weeks ad libitum to induce metabolic abnormality. Treatment was administered at week 8 for four weeks via oral gavage. The rats were sacrificed with anesthesia at the end of the experimental period. Blood, liver, and visceral fat were collected for further analysis. The consumption of 20% fructose water by Wistar rats for eight weeks displayed a tremendous increment in body weight, fat mass, percentage fat, LDL, TG, TC, HMG-CoA reductase, leptin, and reduced the levels of HDL and adiponectin as well as adipocyte hypertrophy. Following the treatment period, FDW-PS and FDW-NGN showed a significant reduction in body weight, fat mass, percentage fat, LDL, TG, TC, HMG-CoA reductase, and leptin with an increment in the levels of HDL and adiponectin compared to the FDW group. FDW-PS and FDW-NGN also showed adipocyte hypotrophy compared to the FDW group. In conclusion, oral administration of 125 mg/kg PS methanolic extract to fructose-induced obese rats led to significant amelioration of obesity and hyperlipidemia through suppressing the adipocytes and inhibiting HMG-CoA reductase. PS has the potential to be used as an alternative or adjunct therapy for obesity and hyperlipidemia.     

Buddleja officinalis Maximowicz extract inhibits lipid accumulation on adipocyte differentiation in 3T3-L1 cells and high-fat mice

Obesity is a global health problem. It is also known to be a risk factor for the development of metabolic disorders, type 2 diabetes, systemic hypertension, cardiovascular disease, dyslipidemia, and atherosclerosis. In this study, we elucidated that Buddleja officinalis Maximowicz extract significantly inhibited lipid accumulation during 3T3-L1 adipocyte differentiation. Furthermore, Buddleja officinalis Maximowicz extract reduced the body weight gain induced through feeding a high-fat diet to C57BL/6 mice. The treatment of Buddleja officinalis Maximowicz extract significantly reduced the adipose tissue weight to 2.7/100 g of body weight in high-fat mice. When their adipose tissue morphology was investigated for histochemical staining, the distribution of cell size in the high-fat diet groups was hypertrophied compared with those from Buddleja officinalis Maximowicz extract-treated mice. In addition, in Buddleja officinalis Maximowicz extract-treated mice, a significant reduction of serum triglyceride and T-cholesterol was observed at to 21% and 17%, respectively. The discovery of bioactive compounds from diet or dietary supplementation is one of possible ways to control obesity and to prevent or reduce the risks of various obesity-related diseases. These results support that Buddleja officinalis Maximowicz extract is expected to create the therapeutic interest with respect to the treatment of obesity.     

Protective Effect of Cudrania tricuspidata Extract against High-Fat Diet Induced Nonalcoholic Fatty Liver Disease through Nrf-2/HO-1 Pathway

Nonalcoholic fatty liver disease is the most common chronic disease affecting a wide range of the world’s population and associated with obesity-induced metabolic syndrome. It is possibly emerging as a leading cause of life-threatening liver diseases for which a drug with a specific therapeutic target has not been developed yet. Previously, there have been reports on the benefits of Cudrania tricuspidata (CT) for treating obesity and diabetes via regulation of metabolic processes, such as lipogenesis, lipolysis, and inflammation. In this study, we investigated the ameliorative effect of orally administered 0.25% and 0.5% (w/w) CT mixed with high-fat diet (HFD) to C57BL/6J mice for 7 weeks. It was found that body weight, fat mass, hepatic mass, serum glucose level, and liver cholesterol levels were significantly reduced after CT treatment. In CT-treated HFD-fed mice, the mRNA expression levels of hepatic lipogenic and inflammatory cytokine-related genes were markedly reduced, whereas the expression level of epididymal lipogenic genes was increased. The mRNA expression level of beta-oxidation and Nrf-2/HO-1 genes significantly increased in CT-treated obese mice livers. We propose that CT alleviates hepatic steatosis by reducing oxidative stress and inflammation.     

Determination of ent-kaurene in subcutaneous fat of Iberian pigs by gas chromatography multi-stage mass spectrometry with the aim to differentiate between intensive and extensive fattening systems

This work presents a gas chromatography multi-stage mass spectrometry (GC-MS³) method for the determination of ent-kaurene in subcutaneous fat of Iberian pig, present in adipose tissue of animals due to pasture ingestion (extensive fattening system). The method comprises a saponification and a liquid-liquid extraction of the unsaponifiable fraction, followed by an isolation of the hydrocarbon fraction by high performance liquid chromatography (HPLC) and analysis by GC-MS³ (ion trap) with electronic ionization. The GC-MS³ analysis allows the isolation and characterization of specific fragments from the original (MS¹) molecular structure, and particularly, those fragments originated from the precursor ion (m/z = 229) characteristic of ent-kaurene. The MS/MS product fragment m/z = 213 is used as a further precursor fragment giving rise to a MS³ spectrum specific for ent-kaurene. The limit of detection of the MS³ technique is lower than 0.2 μg kg⁻¹ and a linear regression has been found between 0.2 and 112 μg kg⁻¹. This method is applicable for the determination of the fattening system of the Iberian pig.