Effects of novel vaccines on weight loss in diet-induced-obese （DIO） mice

The purpose of the study was to test the therapeutic effects of novel vaccines for reducing weight gain and increasing weight loss in diet induced obesity (DIO) model. Male C57BL/6 J mice, fed a 60% Kcal fat diet for 8 weeks prior to the start of the study, were vaccinated via the intraperitoneal route with two formulations (JH17 & JH18) of chimeric-somatostatin vaccines at 1 and 22 days of the study. Control mice were injected with PBS. All mice continued to be feed the 60% Kcal fat diet for the 6 week study. Body weights were measured two times a week and food intake was measured weekly. At week 6, mice were euthanized and a terminal bleed was made and antibody levels to somatostatin and levels of insulin-like growth factor 1 (IGF-1) were determined. Vaccination with both vaccine formulations induced a statistically significant body weight change over the study period, as compared with PBS controls. Percentage of baseline body weight was also significantly affected by vaccination during the study period. Vaccinates finished the study at 104% and 107% of baseline weight, JH17 & JH18 respectively, while untreated controls reached 115% of baseline weight. Food intake per mouse was similar in all mouse groups during the entire study. Control mice did not demonstrate any antibody titers to somatostatin, while all vaccinated mice had measurable antibody responses (> 1:500,000 titer). IGF-1 levels were not statistically significant among the groups, but were elevated in the JH18 vaccinates (mean 440.4 ng/mL) when compared with PBS controls (mean 365.6 ng/mL). Vaccination with either JH17 or JH18 chimeric-somatostatin vaccines produced a statistically significant weight loss as compared with PBS controls (P < 0.0001), even though the DIO mice with continually fed a 60% Kcal fat diet. The weight loss/lower weight gain observations were even more significant, as all mice consumed similar amounts of food for the entire study. The presence of high levels of anti-somatostatin antibodies at 6 weeks was correlative with the weight observations and confirmed the success of vaccination.     

Potential effects of lignan-enriched flaxseed powder on bodyweight, visceral fat, lipid profile, and blood pressure in rats

The potential effects of secoisolariciresinol diglucoside lignan-enriched flaxseed powder (LEFP) on bodyweight, visceral fat, lipid profile, adipokines, and blood pressure were investigated using rats, divided into four groups (n=8); a normal control diet (NC), a normal control diet with 0.02% LEFP (NCL), a high-fat and high-fructose diet (HFD), or a high-fat and high-fructose diet with 0.02% LEFP (HFDL). Liver, heart, kidney, adipose tissues, and blood were collected following 12-weeks on the diets. The average body weight of the HFD group was significantly higher than those of the NC, NCL, and the HFDL groups (P<0.05). Also, the average weights of kidneys from the HFD and HFDL groups was higher than those of the NC and NCL groups (P<0.05), although not significantly different in the weights of livers and hearts. The visceral fat weight was significantly higher in rats in the HFD group, but notably reduced in the HFDL fed rats (P<0.05). Accordingly, plasma leptin increased significantly in rats fed the HFD diet, higher than rats fed the HFDL diet. Also, the rats in the HFDL group showed improved lipid profile, compared to the rats in the HFD group (P<0.05). Furthermore, a significant reduction in blood pressure was observed in the rats of the HFDL group compared to the HFD group (P<0.05). These data suggest that the LEFP supplementation may provide beneficial effects such as the reduction of bodyweight and fat accumulation, the lipid profile improvement, and blood pressure control.     

A proteomic analysis of serum from dogs before and after a controlled weight-loss program

The objective of this study was to investigate how weight-loss program would alter the proteome of the serum of Beagle dogs. For this purpose, serum samples from 5 Beagle dogs, before and after weight loss, were analyzed using 2-dimensional electrophoresis. Protein profiles of all samples were obtained, divided into 2 classes (obese and lean), and compared using specific 2-dimensional software, giving a total of 144 spot matches. Statistical analysis revealed 3 spot matches whose expressions were modulated in response to weight loss: 2 protein spots were upregulated and 1 protein spot was downregulated in the obese state in comparison with the lean state of the dogs. Mass spectrometric identification of differentially regulated spots revealed that these protein spots corresponded to retinol-binding protein 4, clusterin precursor, and α-1 antitrypsin, respectively, which could be considered potential markers of obesity and obesity-related disease processes in dogs.     

Prevalence and risk factors for the development of diabetes mellitus in Swedish cats

Background

The prevalence and risk factors for the development of feline diabetes mellitus (FDM) in Swedish cats have not previously been reported. The objective of the present pilot study was to indicate prevalence and possible risk factors for FDM in Swedish cats. Twenty diabetic cats from the database at the University Animal Hospital in Uppsala participated in the study, and these were matched with 20 healthy controls on sex and age. A mail-and-telephone questionnaire focusing on diet, activity and obesity was used.

Results

The prevalence of FDM during the years 2000–2004 based on the results of the hospital records in the present study was 21 per 10,000 cats. The diabetic cats were on average 9 years old when the disease signs were discovered (median, min-max 2–15). Among FDM cases, it was more common to be male (n=17 males vs n=3 females; P≤0.05). Ten out of twenty owners to cases (50%) reported their cats to be obese at the time of the diagnosis (median 9 years, min-max 2–15), as compared to five out of twenty (25%) controls at the same age. The median BW at the time for diagnosis was 5.5 kg (min-max 2.0-9.0) for cases, and 5.0 kg (min-max 3.0-8.0 kg) for controls, respectively. Despite that both cases and controls had the same median age at the time of the study (13 years, min-max 3–18), a significantly higher number of controls were alive at that age (n=16 controls vs 8 cases; P≤0.05). A significantly higher proportion of cases that were obese at the time of the FDM diagnosis were dead at the time of the study compared to the proportion of controls that were obese at a similar age (P≤0.05).The diets given at the time for diagnosis for cases compared to diet of the controls at a similar time were mainly commercial foods, and controls consumed a higher proportion of dry foods compared to cases (medians 79 vs 44% of DM intake/d, respectively; P≤0.05). Cases were less active compared to the controls (2.3 and 3.2 h/d, respectively; P≤0.05).

Conclusions

The results indicate that the proportions of dry foods in the diet, to perform low activity and to be obese could be identified as preliminary risk factors for FDM in Swedish cats, and should be taken into account in preventive measures as well as in the design of future epidemiological studies in this population.     

Correlation among plasma leptin,resistin an type 2 diabetes mellitus

AIM：To assess the association of resistin,obesity,serum lipid levels and insulin resistance with plasma leptin.METHODS：The concentrations of fasting serum glucose,insulin,lipid profiles,plasma resistin and leptin were assayed in 80 cases (including 37 controls with normal glucose tolerance and 43 patients with type 2 diabetes mellitus).RESULTS：Fasting plasma leptin level was positively correlated with sex,body mass index (BMI),waist circumference (WC),waist-hip ratio and fasting serum insulin (F Ins) （P<0.01）.Fasting plasma leptin level was negatively correlated with insulin sensitivity index (r=-0.373,P<0.01).There was no correlation between the concentrations of plasma leptin and FPG,TG,TC and resistin （P>0.05）.CONCLUSION：Fasting plasma leptin level is positively correlated with obesity and insulin resistance,not resistin.Leptin may play a role in the pathogenesis of type 2 diabetes mellitus.     

Leptin and obesity

Obesity is a severely public health problem the whole society faces, and it is correlated closely with many diseases, such as diabetes, hypertension, coronary heart disease, gallstone, and so on. Therefore it threatens people's survival quality severely. Obesity is a multiple-factor disease including genetic, metabolic and behavioral factor, and the gene is the main determining factor. With the development of molecular biology technique, people have founded several genes involved in obesity. Among these genes, the research on obese gene is the most profound. The protein leptin is the expression product of the obese gene. This review elucidates the structure, the main biological function, the mechanism of leptin and it's relationship with obesity.     

Improvement of insulin sensitivity by osteocalcin inhibits inflammation in the adipose tissue of obese mice

AIM: To explore the improving effect of osteocalcin on obesity-related insulin resistance and inflammation in the adipose tissue of obese mice.METHODS: The C57BL/6 mice were fed with high-fat diet for 12 weeks to obtain obese mice. Osteocalcin (30 ng/kg or 3 ng/kg) and saline solution (control) were intraperitoneally injected for other 4 weeks. The fat mass, body weight, serum triglycerides and serum free fatty acid were analyzed. Intraperitoneal glucose tolerance test and insulin tolerance test were carried out. Macrophage infiltration degree in the adipose tissue was observed by immunohistochemical staining. The mRNA expression of monocyte chemotactic protein-1 (MCP-1) and CD68 was detected by real-time fluorescence quantitative PCR.RESULTS: Osteocalcin (30 ng/kg or 3 ng/kg) treatment for 4 weeks significantly reduced the body weight, fat mass and insulin level, and improved abnormal glucose tolerance and insulin resistance in the obese mice. Moreover, the macrophage infiltration decreased, and the mRNA expression of MCP-1 and CD68 was down-regulated in the adipose tissue of obese mice treated with osteocalcin at 30 ng/kg.CONCLUSION: Osteocalcin at 30 ng/kg significantly reduces body weight and fat mass, and attenuates the severity of insulin resistance through down-regulating the mRNA expression of MCP-1 and CD68 and inbihiting macrophage infiltration in the adipose tissue of obese mice induced by high-fat diet.