Moderate quantity of lard mixed with sunflower oil attenuate lipid accumulation in mice

Lard, a fat rich in saturated fatty acids (SFAs), is regarded as a risk factor for metabolic diseases. In the present study, effect of different lard blended with sunflower oil diets on lipid accumulation in adipose tissue, liver, and serum by mouse model was researched. Body weight, body fat percentage, cross-sectional area of adipocytes, liver triglycerides (TGs), and oil red stained area in mice liver of lard blend sunflower oil (L-SFO) group were significantly lower than those of sunflower oil (SFO) group, whereas no significant differences were observed between mice of lard and L-SFO groups. Serum TG and free fatty acid levels were significantly lower in L-SFO group than in other two groups. Furthermore, data showed that sunflower oil decreased contents of hormone-sensitive lipase and carnitine palmitoyl transferase 1 (CPT-1) and increased fatty acid synthase activity in liver tissue. A mixture of lard and sunflower oil rather than only sunflower oil or lard might promote body fat loss and reduce lipid accumulation in adipose tissue, serum, and liver by promoting hydrolysis of TG, increasing β-oxidation of fatty acids. These data suggested that mixing lard and vegetable oil (e.g. sunflower oil) for cooking, or alternate using lard and vegetable oil could be beneficial for reducing body fat.     

辽宁阜新农村居民心肌梗死的流行病学特征及危险因素调查

目的了解北方农村地区成年人群心肌梗死的流行病学特征和相关危险因素,为北方农村地区心肌梗死的防治和干预提供科学依据。方法采用随机分层整群抽样对辽宁省阜新地区的7个乡镇≥35岁30214名农村常驻(≥5年)成年人进行了调查。由培训过的医师对调查对象进行了血压测量和常见心肌梗死危险因素资料的收集。结果辽宁省农村居民心肌梗死患病率为0.29%,标化率为0.28%;男性患病率为0.26%(标化率0.25%),女性患病率为0.32%(标化率0.31%),性别间差异无显著性(χ2=0.90,P=0.342)。随着年龄和血压分级的增高,心肌梗死患病率呈明显增高趋势。多元Logistic逐步回归分析表明年龄、超重、肥胖、高血压家族史、高血压、吸烟和爱吃咸食等因素是心肌梗死患病的危险因素。其中肥胖人群患心肌梗死的调整优势比是体质正常人群的6.08倍(95%CI为2.84～13.03)。结论辽宁省农村居民心肌梗死患病率较高,肥胖、高血压是心肌梗死最显著的危险因素,而许多居民对心肌梗死危险因素的防治知识非常匮乏。应提高农村居民对心肌梗死危险因素和相关知识的认识度,以降低心肌梗死的患病危险性。     

Adult human mesenchymal stem cell differentiates into adipocytes

AIM:To investigate the differentiation from human mesenchymal stem cells (hMSC) to adipocytes.METHODS: hMSC were separated from rib marrow and expanded in culture medium. To detect the surface antigens, the labeled cells were analysed on a FACScan flow cytometer. hMSC were induced with dexamethasone, insulin, 1-methy1-3-isobutylxanthine and indomethacin which acted as adipocyte differentiation inducer. The cells were stained with Oil Red O. The number of adipocytes were counted on a phase-contrast microscope.RESULTS: hMSC were expanded as undifferentiated cells in culture for more than 5 passages. The isolated cultured MSC comprised a single phenotypic population and displayed a fibroblast-like morphology. These expanded, attached MSC were uniformly positive for CD29, CD44, CD90, CD105, CD166 and didn't express CD14, CD34, CD45, CD11a. After induced with induction medium, lipid vacuoles were first detectable within the cells at 48 hours. Two weeks later, more than 85% MSC differentiated into adipocytes which displayed a perinuclear accumlation of lipid vacuoles, as detected by Oil Red O. CONCLUSION:hMSC can be induced to differentiate into adipocytes.     

Experimental study on preventing obesity by compound rhubarb preparation in rats

AIM: To investigate the effect of compound rhubarb preparation (Kintop) in preventing obesity in rats and its probable mechanism involved. METHODS:Twenty-six newborn SD rats were randomly grouped as rhubarb preparation plus high-energy forage group(n=8), high-energy forage control group(n=8) and ordinary forage control group(n=10). The rats in rhubarb preparation plus high-energy forage group and high-energy forage control group were fed with high-energy forage and those in ordinary forage control group were fed with ordinary forage. The rats in rhubarb preparation plus high-energy forage group were administered by compound rhubarb preparation (40 mg·100 g^-1 body weight·d^-1) from 9th to 17th week. The dynamic changes in body weight, celiac fat weight and adipocytes size were measured. Immunohistochemical analysis of leptin in celiac adipocytes (ABC method) and measurement of serum leptin level (RID method) were performed. RESULTS:The body weight and the wet weights of celiac fat were lower, their adipocytes were smaller and immunohistochemical stainings of leptin were weaker in rhubarb preparation plus high-energy forage group than those in high-energy forage control group. There was an obvious positive correlation between the expression of leptin and celiac fat tissue weight(r=0.8663, P＜0.05). But the changes in serum leptin were not significant between groups. CONCLUSION:Compound rhubarb preparation (40 mg·100 g^-1 body weight·d^-1) can prevent the obesity in rats fed with high-energy forage. The mechanism might involve the decrease in adipocyte leptin expression.     

Dietary energy restriction and successful weight loss in obese client-owned dogs

BACKGROUND: Obesity is the most common nutritional disease in dogs. Although weight loss by dietary caloric energy restriction is successful in experimental studies, there is limited information on success of such programs in client-owned dogs who are obese. Further, no information currently exists on the changes in body composition during weight loss in clinical cases. HYPOTHESIS: Key determinants of outcome of weight loss, including energy allocation and body composition, are influenced by both individual and weight program factors. ANIMALS: Nineteen client-owned dogs with naturally occurring obesity. METHODS: In this prospective clinical study, body composition was quantified by dual-energy X-ray absorptiometry before and after weight loss on an individually tailored program that incorporated a high-protein and moderate-fiber diet. RESULTS: Mean percentage weight loss was 18% (range, 6-29%), and mean rate of weight loss was 0.85% per week (range, 0.35-1.56%). Mean energy allocation required to achieve weight loss was 60% of maintenance energy requirement at target weight (MERTW) (range, 50-82%). Significant dietary noncompliance was reported (mean, 1.0% MERTW; range, 0.0-9.5%). The mean composition of tissue lost was 84: 15:1 (fat : lean : bone mineral content [BMC]). Lean tissue loss was positively associated with overall percentage of weight loss (Pearson correlation coefficient [Rp] = 0.591, P = .008), whereas BMC loss was greater in retrievers compared with other breeds (1.9% +/- 1.16% versus 0.8% +/- 0.44%; P = .008). CONCLUSIONS AND CLINICAL IMPORTANCE: This clinical study demonstrated body composition changes during weight loss in dogs. Conventional programs produced safe weight loss, but marked energy restriction was required and the rate of loss was slower than in experimental studies.     

Effect of GLP-1 receptor agonist on lipolysis in adipose tissue of obese mice and its underlying mechanism

AIM: To investigate the effects of glucagon-like peptide-1(GLP-1) receptor agonist exendin-4 on white adipose tissue (WAT) and the underlying mechanisms. METHODS: Male C57BL/6J mice (8 weeks) were challenged by high-fat diet for 12 weeks, and were randomly divided into saline group and exendin-4 group. The mRNA expression of sirtuin 1(SIRT1), adipose triglyceride lipase (ATGL), TNF-α and adiponectin of WAT was detected by real-time PCR. 3T3-L1 adipocytes or mouse embryonic fibroblasts cells were treated with exendin-4 for 24 h. The protein levels of SIRT1, ATGL and hormone-sensitive lipase (HSL) were determined by Western blot.RESULTS: Exendin-4 significantly decreased epididymal fat weight, fasting blood glucose and serum triglyceride levels (P<0.05), and reduced body weight and serum TNF-α level. The mRNA expression of SIRT1, ATGL and adiponectin in WAT was all significantly up-regulated by exendin-4, which were contrary to the down-regulation of TNF-α mRNA expression (P<0.05). Exendin-4 promoted the protein expression of SIRT1, ATGL, and HSL in 3T3-L1 adipocytes in a dose-dependent manner. Less lipid droplets with up-regulation of lipolytic protein expression were observed when combined with SIRT1 agonist treatment, which were suppressed by SIRT1 inhibitor. Deletion of SIRT1 led to larger adipocytes with more lipid droplets, and the effect of exendin-4 on the lipolysis disappeared when SIRT1 was deficient.CONCLUSION: Exendin-4 promotes lipolysis in WAT of obese mice via activation of SIRT1.