Effect of a High-Fructose Weight-Maintaining Diet on Lipogenesis and Liver Fat

CONTEXT

Consumption of high-fructose diets promotes hepatic fatty acid synthesis (de novo lipogenesis [DNL]) and an atherogenic lipid profile. It is unclear whether these effects occur independent of positive energy balance and weight gain.

OBJECTIVES

We compared the effects of a high-fructose, (25% of energy content) weight-maintaining diet to those of an isocaloric diet with the same macronutrient distribution but in which complex carbohydrate (CCHO) was substituted for fructose.

DESIGN, SETTING, AND PARTICIPANTS

Eight healthy men were studied as inpatients for consecutive 9-day periods. Stable isotope tracers were used to measure fractional hepatic DNL and endogenous glucose production (EGP) and its suppression during a euglycemic-hyperinsulinemic clamp. Liver fat was measured by magnetic resonance spectroscopy.

RESULTS

Weight remained stable. Regardless of the order in which the diets were fed, the high-fructose diet was associated with both higher DNL (average, 18.6 ± 1.4% vs 11.0 ± 1.4% for CCHO; P = .001) and higher liver fat (median, +137% of CCHO; P = .016) in all participants. Fasting EGP and insulin-mediated glucose disposal did not differ significantly, but EGP during hyperinsulinemia was greater (0.60 ± 0.07 vs 0.46 ± 0.06 mg/kg/min; P = .013) with the high-fructose diet, suggesting blunted suppression of EGP.

CONCLUSION

Short-term high-fructose intake was associated with increased DNL and liver fat in healthy men fed weight-maintaining diets.

Induction of Energy Expenditure by Sitagliptin Is Dependent on GLP-1 Receptor

Sitagliptin (SG) increases serum GLP-1 (Glucagon-like peptide-1) through inhibition of the hormone degradation. Resistant starch (RS) induces GLP-1 expression by stimulating L-cells in the intestine. Sitagliptin and resistant starch may have a synergistic interaction in the induction of GLP-1. This possibility was tested in current study in a mouse model of type 2 diabetes. Hyperglycemia was induced in the diet-induced obese mice by a signal injection of streptozotocin (STZ). Sitagliptin (0.4g/100g diet) was tested in the mice (n = 55) with dietary RS (HAM-RS2) at three dosages (0, 15, or 28g/100g diet). Energy and glucose metabolism were monitored in the evaluation of synergistic activity, and GLP-1 activity was determined in the GLP-1 receptor knockout (KO) mice. In the wild type mice, body weight and adiposity were reduced by sitagliptin, which was enhanced by RS (28g). Serum GLP-1 was induced and energy expenditure was enhanced by sitagliptin. Fasting glucose, insulin, and leptin levels were decreased by sitagliptin. The sitagliptin effects were lost in the KO mice (n = 25) although induction of serum GLP-1 by sitagliptin was even stronger in KO mice. The data suggests that sitagliptin is able to reduce adiposity and insulin resistance through induction of energy expenditure. The effect of sitagliptin is partially enhanced by RS. GLP-1 receptor may regulate serum GLP-1 by facilitating the hormone clearance.

Analysis of the liver lipidome reveals insights into the protective effect of exercise on high-fat diet-induced hepatosteatosis in mice

The accumulation of lipid at ectopic sites, including the skeletal muscle and liver, is a common consequence of obesity and is associated with tissue-specific and whole body insulin resistance. Exercise is well known to improve insulin resistance by mechanisms not completely understood. We performed lipidomic profiling via mass spectrometry in liver and skeletal muscle samples from exercise-trained mice to decipher the lipid changes associated with exercise-induced improvements in whole body glucose metabolism. Obesity and insulin resistance were induced in C57BL/6J mice by high-fat feeding for 4 wk. Mice then underwent an exercise training program (treadmill running) 5 days/wk (Ex) for 4 wk or remained sedentary (Sed). Compared with Sed, Ex displayed improved (P < 0.01) whole body metabolism as measured via an oral glucose tolerance test. Deleterious lipid species such as diacylglycerol (P < 0.05) and cholesterol esters (P < 0.01) that accumulate with high-fat feeding were decreased in the liver of trained mice. Furthermore, the ratio of phosphatidylcholine (PC) to phosphatidylethanolamine (PE) (the PC/PE ratio), which is associated with membrane integrity and linked to hepatic disease progression, was increased by training (P < 0.05). These findings occurred without corresponding changes in the skeletal muscle lipidome. A concomitant decrease (P < 0.05) was observed for the fatty acid transporters CD36 and FATP4 in the liver, suggesting that exercise stimulates a coordinated reduction in fatty acid entry into hepatocytes. Given the important role of the liver in the regulation of whole body glucose homeostasis, hepatic lipid regression may be a key component by which exercise can improve metabolism.

The brighter (and evolutionarily older) face of the metabolic syndrome: evidence from Trypanosoma cruzi infection in CD-1 mice

BACKGROUND

Infection with Trypanosoma cruzi, the protozoan parasite that causes Chagas disease, results in chronic infection that leads to cardiomyopathy with increased mortality and morbidity in endemic regions. In a companion study, our group found that a high-fat diet (HFD) protected mice from T. cruzi-induced myocardial damage and significantly reduced post-infection mortality during acute T. cruzi infection.

METHODS

In the present study metabolic syndrome was induced prior to T. cruzi infection by feeding a high fat diet. Also, mice were treated with anti-diabetic drug metformin.

RESULTS

In the present study, the lethality of T. cruzi (Brazil strain) infection in CD-1 mice was reduced from 55% to 20% by an 8-week pre-feeding of an HFD to induce obesity and metabolic syndrome. The addition of metformin reduced mortality to 3%.

CONCLUSIONS

It is an interesting observation that both the high fat diet and the metformin, which are known to differentially attenuate host metabolism, effectively modified mortality in T. cruzi-infected mice. In humans, the metabolic syndrome, as presently construed, produces immune activation and metabolic alterations that promote complications of obesity and diseases of later life, such as myocardial infarction, stroke, diabetes, Alzheimer's disease and cancer. Using an evolutionary approach, we hypothesized that for millions of years, the channeling of host resources into immune defences starting early in life ameliorated the effects of infectious diseases, especially chronic infections, such as tuberculosis and Chagas disease. In economically developed countries in recent times, with control of the common devastating infections, epidemic obesity and lengthening of lifespan, the dwindling benefits of the immune activation in the first half of life have been overshadowed by the explosion of the syndrome's negative effects in later life.

Abatacept improves whole-body insulin sensitivity in rheumatoid arthritis: an observational study

Rheumatoid arthritis (RA) is characterized by increased insulin resistance, a well-known risk factor for diabetes and cardiovascular diseases. The aim of the present study was to evaluate the effect of abatacept on insulin sensitivity in RA patients with moderate to severe disease despite treatment with methotrexate. Fifteen RA patients were recruited for the present study. Patients were evaluated at time 0 and after 6 months of the treatment with i.v. abatacept at the dosage recommended for weight range. Evaluation included oral glucose tolerance test (OGTT) at both time points. Insulin sensitivity was estimated with insulin sensitivity index (ISI) by Matsuda, a measure of whole-body insulin sensitivity. ISI significantly increased after the treatment with abatacept from 3.7 ± 2.6 to 5.0 ± 3.2 (P = 0.003) with a mean difference of 1.23. Analysis of glucose and insulin values during OGTT revealed a reduction of both glucose (303.9 ± 73.4 mg/dL min versus 269.2 ± 69.5 mg/dL min, P = 0.009) and insulin (208.4 ± 119.7 mg/dL min versus 158.0 ± 95.3 mg/dL min, P = 0.01) area under the curves (AUCs). Accordingly also glycated hemoglobin significantly improved (5.5 ± 0.4% versus 5.3 ± 0.3%, P = 0.04). No significant differences were found for measures of β-cell function insulinogenic index (1.11 ± 1.19 versus 1.32 ± 0.82, P = 0.77) and oral disposition index (2.0 ± 5.4 versus 6.0 ± 6.0, P = 0.25). Treatment with abatacept seems to be able to improve whole-body insulin sensitivity in RA patients without affecting β-cell function.

Modulation of the leptin receptor mediates tumor growth and migration of pancreatic cancer cells

Obesity has been implicated as a significant risk factor for development of pancreatic cancer. In the setting of obesity, a systemic chronic inflammatory response is characterized by alterations in the production and secretion of a wide variety of growth factors. Leptin is a hormone whose level increases drastically in the serum of obese patients. High fat diet induced obesity in mice leads to an overall increased body weight, pancreatic weight, serum leptin, and pancreatic tissue leptin levels. Here we report the contribution of obesity and leptin to pancreatic cancer growth utilizing an in vivo orthotopic murine pancreatic cancer model, which resulted in increased tumor proliferation with concomitant increased tumor burden in the diet induced obese mice compared to lean mice. Human and murine pancreatic cancer cell lines were found to express the short as well as the long form of the leptin receptor and functionally responded to leptin induced activation through an increased phosphorylation of AKT473. In vitro, leptin stimulation increased cellular migration which was blocked by addition of a PI3K inhibitor. In vivo, depletion of the leptin receptor through shRNA knockdown partially abrogated increased orthotopic tumor growth in obese mice. These findings suggest that leptin contributes to pancreatic tumor growth through activation of the PI3K/AKT pathway, which promotes pancreatic tumor cell migration.

Carbon monoxide reverses adipose tissue inflammation and insulin resistance upon loss of ovarian function

We hypothesized that carbon monoxide (CO) might suppress chronic inflammation, which led to metabolic disturbances. Ovariectomy (OVX) was performed in mice to mimic chronic inflammation secondary to loss of ovarian function. OVX increased fat mass and the infiltration of highly inflammatory CD11c cells into adipose tissue (AT), resulting in a disturbance of glucose metabolism. Treatment of CO attenuated these; CO decreased recruitment of CD11c-expressing cells in AT and reduced expression of CD11c in bone marrow-derived macrophages, protecting them from M1 polarization. Upregulated cGMP and decreased reactive oxygen species were responsible for the inhibitory activity of CO on CD11c expression; knockdown of soluble guanylate cyclase or heme oxygenase-1 using small interfering RNAs reduced this inhibition substantially. Improved OVX-induced insulin resistance (IR) by CO was highly associated with its activity to attenuate AT inflammation. Our results suggest a therapeutic value of CO to treat postmenopausal IR by reducing AT inflammation.

Effects of Piper nigrum extracts: Restorative perspectives of high-fat diet-induced changes on lipid profile, body composition, and hormones in Sprague-Dawley rats

CONTEXT

Piper nigrum Linn (Piperaceae) (PnL) is used in traditional medicine to treat gastric ailments, dyslipidemia, diabetes, and hypertension.

OBJECTIVE

The present study explores the possible protective effects of P. nigrum extracts on high-fat diet-induced obesity in rats.

MATERIALS AND METHODS

High-fat diet-induced obese rats were treated orally with 200 mg/kg bw of different extracts (hexane, ethylacetate, ethanol, and aqueous extracts) of PnL for 42 d. The effects of PnL extracts on body composition, insulin resistance, biochemical parameters, leptin, adiponectin, lipid profile, liver marker enzymes, and antioxidants were studied.

RESULTS AND DISCUSSION

The HFD control group rats showed a substantial raise in body weight (472.8 ± 9.3 g), fat% (20.8 ± 0.6%), and fat-free mass (165.9 ± 2.4 g) when compared with normal control rats whose body weight, fat%, and fat-free mass were 314.3 ± 4.4 g, 6.4 ± 1.4%, and 133.8 ± 2.2 g, respectively. Oral administration of ethyl acetate or aqueous extracts of PnL markedly reduced the body weight, fat%, and fat-free mass of HFD-fed rats. In contrast to the normal control group, a profound increase in plasma glucose, insulin resistance, lipid profile, leptin, thiobarbituric acid reactive substance (TBARS), and the activities of lipase and liver marker enzymes, and a decrease in adiponectin and antioxidant enzymes were noted in HFD control rats. Administration of PnL extracts to HFD-induced obese rats significantly (p < 0.05) restored the above profiles.

CONCLUSION

PnL extracts significantly reduced the body weight, fat%, and ameliorated HFD-induced hyperlipidemia and its constituents.

Relationship of p53 accumulation in peripheral tissues of high-fat diet-induced obese rats with decrease in metabolic and oncogenic signaling of insulin

This paper aimed to explore the role of p53 in adipose and some other peripheral tissues of a diet-induced obese model and targeted it using pharmacological approach to ameliorate diet-induced insulin resistance. Five week old male Wistar rats were randomly divided into three groups and fed on low-fat diet (13% control lean group), high-fat diet (41% obese group), or high-fat diet plus a single dose of pifithrin-α in the end of experiments (PFT group). Insulin, glucose, and other serum parameters were analyzed by standard colorimetric kits. Protein levels were evaluated by immunoblotting and immunofluorescence methods. After 12weeks, both body weight and insulin resistance were significantly higher in obese rats than in the control ones. P53 and PTEN protein levels were markedly elevated in peripheral tissues in addition to adipose tissues. AKT activation was decreased in the peripheral tissues of obese rats and was in correlation with the increase of p53 and PTEN level. Systemic pifithrin-α administration considerably diminished p53 levels and ameliorated AKT phosphorylation in all peripheral tissues including adipose tissues. Interestingly, the systemic inhibition of p53 was in correlation with improving insulin glucose at serum level. The present results clearly showed that p53 activation in peripheral tissues was in correlation with decreased insulin action. These results indicated p53 activation in the peripheral tissues of obese subjects as a protective mechanism against chronic insulin elevation, suggested that p53 could be a new target for the treatment of type 2 diabetes.

Interactive effects of oligofructose and obesity predisposition on gut hormones and microbiota in diet-induced obese rats

OBJECTIVE

Oligofructose (OFS) is a prebiotic that reduces energy intake and fat mass via changes in gut satiety hormones and microbiota. The effects of OFS may vary depending on predisposition to obesity. The aim of this study was to examine the effect of OFS in diet-induced obese (DIO) and diet-resistant (DR) rats.

METHODS

Adult, male DIO, and DR rats were randomized to: high-fat/high-sucrose (HFS) diet or HFS diet + 10% OFS for 6 weeks. Body composition, food intake, gut microbiota, plasma gut hormones, and cannabinoid CB(1) receptor expression in the nodose ganglia were measured.

RESULTS

OFS reduced body weight, energy intake, and fat mass in both phenotypes (P < 0.05). Select gut microbiota differed in DIO versus DR rats (P < 0.05), the differences being eliminated by OFS. OFS did not modify plasma ghrelin or CB(1) expression in nodose ganglia, but plasma levels of GIP were reduced and PYY were elevated (P < 0.05) by OFS.

CONCLUSIONS

OFS was able to reduce body weight and adiposity in both prone and resistant obese phenotypes. OFS-induced changes in gut microbiota profiles in DIO and DR rats, along with changes in gut hormone levels, likely contribute to the sustained lower body weights.

Serum levels of AgRP protein in patients with schizophrenia on clozapine monotherapy

AIM

Agouti-related peptide (AgRP) is one of the hypothalamic hormones that works by increasing appetite and decreasing metabolism, thus leading to weight gain. The aim of the study was to find out if AgRP level in subjects with schizophrenia on clozapine monotherapy is higher compared with healthy controls.

METHODOLOGY

We determined fasting serum AgRP levels in 24 subjects with schizophrenia on clozapine monotherapy and 24 healthy, age- and sex-matched controls. Biochemical and anthropometric measurements were combined with body composition analysis.

RESULTS

There was no difference for AgRP levels between patients taking clozapine and control group (15.00±8.65 vs. 15.33±6.82 pg/mL, p =0.37). We found negative correlations between AgRP levels and total body fat (r =-0.34 and -0.48 in the whole study group and clozapine group, respectively) and positive correlations with lean body mass (r =0.38 and 0.49 in the whole study group and clozapine group, respectively), body water (r =0.34 and 0.49 in the whole study group and clozapine group, respectively) and basal metabolic rate (r =0.42 both in the clozapine and control groups). There were no correlations with age, height, weight, body mass index, fat mass index, abdominal, waist or hip circumferences, waist-hip ratio, blood pressure, total cholesterol, HDL, LDL, triglycerides, uric acid, glucose, insulin, clozapine dose or treatment duration, duration of treatment with antipsychotics and markers for insulin resistance.

CONCLUSION

We cannot conclude that treatment with clozapine is associated with increased level of AgRP. We did not find previously described differences in AgRP levels between obese and non-obese subjects or associations between AgRP and various metabolic parameters.

Beneficial effects of calcitriol on hypertension, glucose intolerance, impairment of endothelium-dependent vascular relaxation, and visceral adiposity in fructose-fed hypertensive rats

Besides regulating calcium homeostasis, the effects of vitamin D on vascular tone and metabolic disturbances remain scarce in the literature despite an increase intake with high-fructose corn syrup worldwide. We investigated the effects of calcitriol, an active form of vitamin D, on vascular relaxation, glucose tolerance, and visceral fat pads in fructose-fed rats. Male Wistar-Kyoto rats were divided into 4 groups (n = 6 per group). Group Con: standard chow diet for 8 weeks; Group Fru: high-fructose diet (60% fructose) for 8 weeks; Group Fru-HVD: high-fructose diet as Group Fru, high-dose calcitriol treatment (20 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding; and Group Fru-LVD: high-fructose diet as Group Fru, low-dose calcitriol treatment (10 ng / 100 g body weight per day) 4 weeks after the beginning of fructose feeding. Systolic blood pressure was measured twice a week by the tail-cuff method. Blood was examined for serum ionized calcium, phosphate, creatinine, glucose, triglycerides, and total cholesterol. Intra-peritoneal glucose intolerance test, aortic vascular reactivity, the weight of visceral fat pads, adipose size, and adipose angiotensin II levels were analyzed at the end of the study. The results showed that the fructose-fed rats significantly developed hypertension, impaired glucose tolerance, heavier weight and larger adipose size of visceral fat pads, and raised adipose angiotensin II expressions compared with the control rats. High- and low-dose calcitriol reduced modestly systolic blood pressure, increased endothelium-dependent aortic relaxation, ameliorated glucose intolerance, reduced the weight and adipose size of visceral fat pads, and lowered adipose angiotensin II expressions in the fructose-fed rats. However, high-dose calcitriol treatment mildly increased serum ionized calcium levels (1.44 ± 0.05 mmol/L). These results suggest a protective role of calcitriol treatment on endothelial function, glucose tolerance, and visceral adiposity in fructose-fed rats.

Dietary exposure to the endocrine disruptor tolylfluanid promotes global metabolic dysfunction in male mice

Environmental endocrine disruptors are implicated as putative contributors to the burgeoning metabolic disease epidemic. Tolylfluanid (TF) is a commonly detected fungicide in Europe, and previous in vitro and ex vivo work has identified it as a potent endocrine disruptor with the capacity to promote adipocyte differentiation and induce adipocytic insulin resistance, effects likely resulting from activation of glucocorticoid receptor signaling. The present study extends these findings to an in vivo mouse model of dietary TF exposure. After 12 weeks of consumption of a normal chow diet supplemented with 100 parts per million TF, mice exhibited increased body weight gain and an increase in total fat mass, with a specific augmentation in visceral adipose depots. This increased adipose accumulation is proposed to occur through a reduction in lipolytic and fatty acid oxidation gene expression. Dietary TF exposure induced glucose intolerance, insulin resistance, and metabolic inflexibility, while also disrupting diurnal rhythms of energy expenditure and food consumption. Adipose tissue endocrine function was also impaired with a reduction in serum adiponectin levels. Moreover, adipocytes from TF-exposed mice exhibited reduced insulin sensitivity, an effect likely mediated through a specific down-regulation of insulin receptor substrate-1 expression, mirroring effects of ex vivo TF exposure. Finally, gene set enrichment analysis revealed an increase in adipose glucocorticoid receptor signaling with TF treatment. Taken together, these findings identify TF as a novel in vivo endocrine disruptor and obesogen in mice, with dietary exposure leading to alterations in energy homeostasis that recapitulate many features of the metabolic syndrome.

Geraniol, alone and in combination with pioglitazone, ameliorates fructose-induced metabolic syndrome in rats via the modulation of both inflammatory and oxidative stress status

Geraniol (GO) potent antitumor and chemopreventive effects are attributed to its antioxidant and anti-inflammatory properties. In the current study, the potential efficacy of GO (250 mg/kg) in ameliorating metabolic syndrome (MetS) induced by fructose in drinking water was elucidated. Moreover, the effect of pioglitazone (5 and 10 mg/kg; PIO) and the possible interaction of the co-treatment of GO with PIO5 were studied in the MetS model. After 4 weeks of treatment, GO and/or PIO reduced the fasting blood glucose and the glycemic excursion in the intraperitoneal glucose tolerance test. GO and PIO5/10 restrained visceral adiposity and partly the body weight gain. The decreased level of peroxisome proliferator activated receptor (PPAR)-γ transcriptional activity in the visceral adipose tissue of MetS rats was increased by single treatment regimens. Though GO did not affect MetS-induced hyperinsulinemia, PIO5/10 lowered it. Additionally, GO and PIO5/10 suppressed glycated hemoglobin and the receptor for advanced glycated end products (RAGE). These single regimens also ameliorated hyperuricemia, the disrupted lipid profile, and the elevated systolic blood pressure evoked by MetS. The rise in serum transaminases, interleukin-1β, and tumor necrosis factor-α, as well as hepatic lipid peroxides and nitric oxide (NO) was lowered by the single treatments to different extents. Moreover, hepatic non-protein thiols, as well as serum NO and adiponectin were enhanced by single regimens. Similar effects were reached by the combination of GO with PIO5; however, a potentiative interaction was noted on fasting serum insulin level, while synergistic effects were reflected as improved insulin sensitivity, as well as reduced RAGE and triglycerides. Therefore, GO via the transcriptional activation of PPAR-γ reduces inflammation and free radical injury produced by MetS. Thereby, these effects provide novel mechanistic insights on GO management of MetS associated critical risk factors. Moreover, the co-administration of GO to PIO5 exalted the antidiabetic drug anti-MetS efficacy.

Medium-Chain Triglyceride Activated Brown Adipose Tissue and Induced Reduction of Fat Mass in C57BL/6J Mice Fed High-fat Diet

OBJECTIVE

To investigate activation of brown adipose tissue (BAT) stimulated by medium-chain triglyceride (MCT).

METHODS

30 Male C57BL/6J obese mice induced by fed high fat diet (HFD) were divided into 2 groups, and fed another HFD with 2% MCT or long-chain triglyceride (LCT) respectively for 12 weeks. Body weight, blood biochemical variables, interscapular brown fat tissue (IBAT) mass, expressions of mRNA and protein of beta 3-adrenergic receptors (β3-AR), uncoupling protein-1 (UCP1), hormone sensitive lipase (HSL), protein kinase A (PKA), and adipose triglyceride lipase (ATGL) in IBAT were measured.

RESULTS

Significant decrease in body weight and body fat mass was observed in MCT group as compared with LCT group (P<0.05) after 12 weeks. Greater increases in IBAT mass was observed in MCT group than in LCT group (P<0.05). Blood TG, TC, LDL-C in MCT group were decreased significantly, meanwhile blood HDL-C, ratio of HDL-C/LDL-C and norepinephrine were increased markedly. Expressions of mRNA and protein of β3-AR, UCP1, PKA, HSL, ATGL in BAT were greater in MCT group than in LCT group (P<0.05).

CONCLUSION

Our results suggest that MCT stimulated the activation of BAT, possible via norepinephrine pathway, which might partially contribute to reduction of the body fat mass in obese mice fed high fat diet.

Rare sugar D-psicose prevents progression and development of diabetes in T2DM model Otsuka Long-Evans Tokushima Fatty rats

BACKGROUND

The fundamental cause of overweight and obesity is consumption of calorie-dense foods. We have introduced a zero-calorie sweet sugar, d-psicose (d-allulose), a rare sugar that has been proven to have strong antihyperglycemic and antihyperlipidemic effects, and could be used as a replacement of natural sugar for the obese and diabetic subjects.

AIM

Above mentioned efficacy of d-psicose (d-allulose) has been confirmed in our previous studies on type 2 diabetes mellitus (T2DM) model Otsuka Long-Evans Tokushima Fatty (OLETF) rats with short-term treatment. In this study we investigated the long-term effect of d-psicose in preventing the commencement and progression of T2DM with the mechanism of preservation of pancreatic β-cells in OLETF rats.

METHODS

Treated OLETF rats were fed 5% d-psicose dissolved in water and control rats only water. Nondiabetic control rats, Long-Evans Tokushima Otsuka (LETO), were taken as healthy control and fed water. To follow the progression of diabetes, periodic measurements of blood glucose, plasma insulin, and body weight changes were continued till sacrifice at 60 weeks. Periodic in vivo body fat mass was measured. On sacrifice, pancreas, liver, and abdominal adipose tissues were collected for various staining tests.

RESULTS

d-Psicose prevented the commencement and progression of T2DM till 60 weeks through the maintenance of blood glucose levels, decrease in body weight gain, and the control of postprandial hyperglycemia, with decreased levels of HbA1c in comparison to nontreated control rats. This improvement in glycemic control was accompanied by the maintenance of plasma insulin levels and the preservation of pancreatic β-cells with the significant reduction in inflammatory markers. Body fat accumulation was significantly lower in the treatment group, with decreased infiltration of macrophages in the abdominal adipose tissue.

CONCLUSION

Our findings suggest that the rare sugar d-psicose could be beneficial for the prevention and control of obesity and hyperglycemia with the preservation of β-cells in the progression of T2DM.

The effect of early-life stress and chronic high-sucrose diet on metabolic outcomes in female rats

Early-life stress affects metabolic outcomes and choice of diet influences the development of metabolic disease. Here we tested the hypothesis that chronic sugar intake exacerbates metabolic deficits induced by early-life stress. Early-life stress was induced in Sprague-Dawley rats using limited nesting material in early lactation (LN, postnatal days 2-9), and siblings were given chow alone or with additional sucrose post weaning (n = 9-17 per group). Female control and LN siblings had unlimited access to either chow plus water, or chow and water plus 25% sucrose solution (Sucrose), from 3-15 weeks of age. Weekly body weight and food intake were measured. Glucose and insulin tolerance were tested at 13 and 14 weeks of age, respectively. Rats were killed at 15 weeks. Hepatic triglyceride and markers of lipid synthesis - fatty acid synthase, acetyl-CoA carboxylase alpha and oxidation - and peroxisome proliferator-activated receptor gamma coactivator 1-alpha (Pgc-1α) were examined. Mediators of hepatic glucocorticoid metabolism, specifically 11-beta hydroxysteroid dehydrogenase-1 (11βHSD-1), 5-α reductase, and glucocorticoid and mineralocorticoid receptor mRNAs were also measured. Sucrose increased caloric intake in both groups, but overall energy intake was not altered by LN exposure. LN exposure had no further impact on sucrose-induced glucose intolerance and increased plasma and liver triglycerides. Hepatic markers of fat synthesis and oxidation were concomitantly activated and 11βHSD-1 mRNA expression was increased by 53% in LN-Sucrose versus Con-Sucrose rats. Adiposity was increased by 26% in LN-Sucrose versus Con-Sucrose rats. Thus, LN exposure had minimal adverse metabolic effects despite high-sugar diet postweaning.

A dietary phytochemical blend prevents liver damage associated with adipose tissue mobilization in ovariectomized rats

OBJECTIVE

Menopausal reduction in estrogen causes increased adipose accumulation, leading many to turn to dietary supplements to prevent and treat such changes. Enhanced adipose mobilization stimulated by some supplements can increase the risk of non-alcoholic fatty liver disease (NAFLD). Cytoprotective and anti-obesity compounds may prevent the lipotoxicity associated with mobilization.

METHODS

A phytochemical blend was tested in aged, ovariectomized rats. Rats were given the AIN-93M basal diet or a diet containing varying doses of phytochemicals with 2.4 IU/g vitamin D [diet 1: 1000 mg/kg genistein (G); diet 2: 500 mg/kg (G), 200 mg/kg resveratrol (R), and 1000 mg/kg quercetin (Q); diet 3: 1000 mg/kg (G), 400 mg/kg (R), and 2000 mg/kg (Q)].

RESULTS

Serum free fatty acids and hepatic triglycerides were elevated with diets 2 and 3. Despite this increase, the phytochemical blends did not increase apoptotic, cell repair, or remodeling gene expression. The highest phytochemical dose prevented increases in serum alanine aminotransferase.

CONCLUSIONS

Adverse hepatic effects secondary to ovariectomy were mitigated through the inclusion of a dietary phytochemical blend in aged ovariectomized rats. The use of such compounds may not only help with weight management and disease risk in menopausal women, but may also prevent the lipotoxicity in NAFLD.

Twelve-month treatment with Liraglutide ameliorates Visceral Adiposity Index and common cardiovascular risk factors in type 2 diabetes outpatients

AIM

In addition to the effects on glycemic control and body weight, GLP-1 receptor agonists may favorably affect other major cardiovascular disease (CVD) risk factors, although currently available data are still sparse. In this retrospective study, we evaluated the effects of 12-month treatment with liraglutide on major CVD risk factors in 115 type 2 diabetes outpatients (60 men and 55 women), on stable hypoglycemic, anti-hypertensive and/or lipid-lowering therapy.

METHODS

Clinical and anthropometric data, metabolic and lipid profile, as well as the Visceral Adiposity Index (VAI), an obesity-related CVD risk factor, were measured in all participants at baseline and after 12-month treatment.

RESULTS

Treatment with liraglutide was associated with a significant reduction from baseline values of fasting blood glucose (-42.1 mg/dl, P < 0.05), HbA1c (-1.5 %, -17 mmol/mol, P < 0.05), body weight (-7.1 kg, P < 0.05), waist circumference (-6.8 cm, P < 0.001), total-cholesterol (-27.4 mg/dl, P < 0.05), LDL-cholesterol (-25.4 mg/dl, P < 0.05), triglycerides (-56.1 mg/dl, P < 0.05), and non-HDL-C (-36.6 mg/dl, P < 0.05) and an increase of HDL-cholesterol concentrations (+9.3 mg/dl, P < 0.001), a significant reduction in both systolic and diastolic blood pressure (-14.7 mmHg, P < 0.001 and -9.0 mmHg, P < 0.05, respectively) and a decrease of VAI values (-1.6, P < 0.001). All these differences were independent of changes in BMI and comparable in men and women.

CONCLUSIONS

In conclusion, 12-month treatment with liraglutide in add-on to on-going hypoglycemic therapy significantly ameliorates all major CVD risk factors and reduces cardiometabolic risk, as estimated by VAI values.

Effects of genistein in combination with conjugated estrogens on endometrial hyperplasia and metabolic dysfunction in ovariectomized mice

Tissue-selective estrogen complex (TSEC), which combines a selective estrogen receptor modulator (SERM) with one or more estrogens, is a novel approach to menopausal therapy. It has been demonstrated that the phytoestrogen genistein (GEN) exhibits mixed estrogen receptor agonist and antagonist activity, suggesting that GEN may have potential for use as a natural SERM. We evaluated, for the first time, the effects of GEN, conjugated estrogens (CE), and their pairing effects as a TSEC treatment on estrogen-induced endometrial hyperplasia and metabolic dysfunction in ovariectomized (OVX) mice fed a high-fat diet. CE replacement prevented fat accumulation in the adipose tissue and liver, improved glucose homeostasis, and induced endometrial hyperplasia in OVX mice. GEN at 100 mg/kg showed CE mimetic effects in preventing ovariectomy-induced metabolic dysfunctions without endometrial stimulation. Combination treatments with CE and GEN prevented metabolic dysfunctions more strongly than CE alone, but at both low and high doses, GEN did not reverse CE-induced endometrial hyperplasia. In addition, we found that in a TSEC regimen, a typical SERM raloxifene maintains the metabolic benefits of CE while simultaneously protecting the endometrium in OVX mice. These findings indicate that GEN acts as an estrogen agonist in metabolic regulation, but has no SERM function in the uteri of OVX mice.

Miglitol protects against age-dependent weight gain in mice: A potential role of increased UCP1 content in brown adipose tissue

Miglitol is an absorbable alpha-glucosidase inhibitor that is used to control post-prandial hyperglycemia. We previously found that miglitol stimulates brown adipose tissue and prevents diet-induced obesity in mice that are fed a high-fat, high-carbohydrate diet. In this study, we examined whether miglitol can also protect against aging-dependent weight gain in mice that are fed a normal chow diet. Male C57Bl/6J mice were fed normal chow with or without miglitol (800 ppm) for 12 weeks, starting at 12 weeks of age. Food intake and body weight were monitored. After 12 weeks, adiposity, energy expenditure, and locomotor activities were measured. After sacrifice, weight of the epididymal white adipose tissue and adipocyte size were measured. Finally, Ucp1 gene expression and UCP1 protein abundance in brown adipose tissue were quantified by RT-PCR and Western analyses, respectively. Miglitol prevented age-related weight gain without affecting growth of the animals. Miglitol-treated mice showed reduced adiposity and increased oxygen consumption compared to controls, accompanied by higher UCP1 protein abundance in brown adipose tissue. Food intake and locomotor activities were not affected. These results suggest that miglitol can protect against age-dependent weight gain. Elucidating the molecular targets of miglitol in brown adipose tissue and optimizing drug delivery and efficacy may provide new strategies to combat obesity.

Juice and water intake in infancy and later beverage intake and adiposity: could juice be a gateway drink?

OBJECTIVES

To examine the tracking and significance of beverage consumption in infancy and childhood.

METHODS

Among 1163 children in Project Viva, we examined associations of fruit juice and water intake at 1 year (0 oz, 1-7 oz [small], 8-15 oz [medium], and ≥16 oz [large]) with juice and sugar-sweetened beverage (SSB) intake and BMI z-score during early (median 3.1 years) and mid-childhood (median 7.7 years).

RESULTS

In covariate adjusted models, juice intake at 1 year was associated with greater juice and SSB intake during early and mid-childhood and also greater adiposity. Children who drank medium and large amounts of juice at 1 year had higher BMI z-scores during both early (medium: β = 0.16 [95% CI = 0.01-0.32]; large: β = 0.28 [95% CI = 0.01-0.56]) and mid-childhood (medium: β = 0.23 [95% CI = 0.07-0.39]; large: β = 0.36 [95% CI = 0.08-0.64]). After covariate adjustment, associations between water intake at 1 year and beverage intake and adiposity later in childhood were null.

CONCLUSIONS

Higher juice intake at 1 year was associated with higher juice intake, SSB intake, and BMI z-score during early and mid-childhood. Assessing juice intake during infancy could provide clinicians with important data regarding future unhealthy beverage habits and excess adiposity during childhood.

Influence of early zoledronic acid administration on bone marrow fat in ovariectomized rats

Although the primary target cell of bisphosphonates is the osteoclast, increasing attention is being given to other effector cells influenced by bisphosphonates, such as osteoblasts and marrow adipocytes. Early zoledronic acid (ZA) treatment to ovariectomized (OVX) rats has been found to fully preserve bone microarchitecture over time. However, little is known regarding the influence of ZA on marrow adipogenesis. The purpose of this study was to monitor the ability of early administration of ZA in restoring marrow adiposity in an estrogen-deficient rat model. Thirty female Sprague-Dawley rats were randomly divided into sham-operated (SHAM), OVX + vehicle, and OVX + ZA groups (n=10/group). Dual-energy x-ray absorptiometry and water/fat magnetic resonance imaging were performed at baseline, 6 weeks, and 12 weeks after treatment to assess bone mineral density and marrow fat fraction. Serum biochemical markers, bone remodeling, and marrow adipocyte parameters were analyzed using biochemistry, histomorphometry, and histopathology, respectively. The expression levels of osteoblast, adipocyte, and osteoclast-related genes in bone marrow were assessed using RT-PCR. The OVX rats showed marked bone loss, first detected at 12 weeks, but estrogen deficiency resulted in a remarked increase in marrow fat fraction, first detected at 6 weeks compared with the SHAM rats (all P < .001). Similarly, the OVX rats had a substantially larger percent adipocyte area (+163.0%), mean diameter (+29.5%), and higher density (+57.3%) relative to the SHAM rats. Bone histomorphometry, levels of osteoclast-related gene expression, and a serum resorption marker confirmed that ZA significantly suppressed bone resorption activities. Furthermore, ZA treatment returned adipocyte-related gene expression and marrow adipocyte parameters toward SHAM levels. These data suggest that a single dose of early ZA treatment acts to reverse marrow adipogenesis occurring during estrogen deficiency, which may contribute to its capacity to reduce bone loss.

Evaluation of a new adipocytolytic solution: adverse effects and their relationship with the number of vials injected

Adipocytolytic therapies have always raised the interest of aesthetic medicine physicians, mainly because of the great potential to achieve spectacular results in localized adiposities reduction. In the last few decades, these results have been severely compromised due to the improper or reckless injection of these products, to the extent of some of them being banned in many countries. Today, there is a new adipocytolytic solution that has been approved, is effective, and has theoretic and empiric consensus regarding its safety. The aim of this study for which 331 therapeutic sessions were retrospectively analyzed is to provide evidence of its safety and efficacy.

Chronic glucocorticoid exposure-induced epididymal adiposity is associated with mitochondrial dysfunction in white adipose tissue of male C57BL/6J mice

Prolonged and excessive glucocorticoids (GC) exposure resulted from Cushing's syndrome or GC therapy develops central obesity. Moreover, mitochondria are crucial in adipose energy homeostasis. Thus, we tested the hypothesis that mitochondrial dysfunction may contribute to chronic GC exposure-induced epididymal adiposity in the present study. A total of thirty-six 5-week-old male C57BL/6J mice (∼20 g) were administrated with 100 µg/ml corticosterone (CORT) or vehicle through drinking water for 4 weeks. Chronic CORT exposure mildly decreased body weight without altering food and water intake in mice. The epididymal fat accumulation was increased, but adipocyte size was decreased by CORT. CORT also increased plasma CORT, insulin, leptin, and fibroblast growth factor 21 concentrations as measured by RIA or ELISA. Interestingly, CORT increased plasma levels of triacylglycerols and nonesterified fatty acids, and up-regulated the expression of both lipolytic and lipogenic genes as determined by real-time RT-PCR. Furthermore, CORT impaired mitochondrial biogenesis and oxidative function in epididymal WAT. The reactive oxygen species production was increased and the activities of anti-oxidative enzymes were reduced by CORT treatment as well. Taken together, these findings reveal that chronic CORT administration-induced epididymal adiposity is, at least in part, associated with mitochondrial dysfunction in mouse epididymal white adipose tissue.