Effects of Consuming Beverages Sweetened with Fructose, Glucose, High-Fructose Corn Syrup, Sucrose, or Aspartame on OGTT-Derived Indices of Insulin Sensitivity in Young Adults.

(1) Background: Clinical results on the effects of excess sugar consumption on insulin sensitivity are conflicting, possibly due to differences in sugar type and the insulin sensitivity index (ISI) assessed. Therefore, we compared the effects of consuming four different sugars on insulin sensitivity indices derived from oral glucose tolerance tests (OGTT). (2) Methods: Young adults consumed fructose-, glucose-, high-fructose corn syrup (HFCS)-, sucrose-, or aspartame-sweetened beverages (SB) for 2 weeks. Participants underwent OGTT before and at the end of the intervention. Fasting glucose and insulin, Homeostatic Model Assessment-Insulin Resistance (HOMA-IR), glucose and insulin area under the curve, Surrogate Hepatic Insulin Resistance Index, Matsuda ISI, Predicted M ISI, and Stumvoll Index were assessed. Outcomes were analyzed to determine: (1) effects of the five SB; (2) effects of the proportions of fructose and glucose in all SB. (3) Results: Fructose-SB and the fructose component in mixed sugars negatively affected outcomes that assess hepatic insulin sensitivity, while glucose did not. The effects of glucose-SB and the glucose component in mixed sugar on muscle insulin sensitivity were more negative than those of fructose. (4) Conclusion: the effects of consuming sugar-SB on insulin sensitivity varied depending on type of sugar and ISI index because outcomes assessing hepatic insulin sensitivity were negatively affected by fructose, and outcomes assessing muscle insulin sensitivity were more negatively affected by glucose.

Should dolutegravir always be withheld in people with HIV on dolutegravir with incident diabetes mellitus? a case report.

Dolutegravir (DTG), an integrase strand transfer inhibitor is currently the recommended first and second line anti-retroviral therapy (ART) anchor agent by the World Health Organization due to its favorable side effect profile, high efficacy and genetic barrier to resistance.Despite its very good side effect profile, there have been multiple case reports of ART experienced patients developing hyperglycemia within weeks to a few months after switching to DTG preceded by weight loss. At population level, however, DTG as well as other integrase inhibitors have been demonstrated to have a reduced risk of incident diabetes mellitus (T2DM) compared to other HIV drug classes.Following multiple similar reports of accelerated hyperglycemia in Uganda during the first pilot year of DTG use, the Uganda Ministry of Health recommended withholding dolutegravir in all patients who develop diabetes. Whether this recommendation should be applied to all patients with incident T2DM remains to be demonstrated.We present a clinical case of an HIV positive ART naïve man who was diagnosed with T2DM after 36 weeks on DTG. We describe changes in blood glucose, glycated hemoglobin, insulin resistance and pancreatic beta cell function before and after withholding DTG. We demonstrated that he was phenotypically different from the reported cases of accelerated hyperglycemia and he continued to have worsening insulin resistance despite withholding DTG. His blood glucose improved with dietary T2DM management. It is possible he had an inherent risk of developing T2DM independent of his exposure to DTG. This put in question whether DTG should universally be withheld in PLHIV with incident T2DM in Uganda.

Should dolutegravir always be withheld in people with HIV on dolutegravir with incident diabetes mellitus? A case report.

Dolutegravir (DTG), an integrase strand transfer inhibitor is currently the recommended first and second line anti-retroviral therapy (ART) anchor agent by the World Health Organization. This followed widespread reports of primary resistance to non-nucleoside reverse transcriptase inhibitors. Despite its very good side effect profile, there have been multiple case reports of ART experienced patients developing hyperglycemia within weeks to a few months after switching to DTG preceded by weight loss. At population level, however, dolutegravir as well as other integrase inhibitors have been demonstrated to have a reduced risk of incident diabetes mellitus (T2DM) compared to other HIV drug classes. Following multiple similar reports of accelerated hyperglycemia in Uganda during the first pilot year of DTG use, the Uganda Ministry of Health recommended withholding dolutegravir in all patients who develop diabetes. Whether this recommendation should be applied to all patients with incident T2DM remains to be demonstrated. We present a clinical case of an HIV positive ART naïve man who was diagnosed with T2DM after 36 weeks on dolutegravir. We describe changes in blood glucose, glycated hemoglobin, insulin resistance and pancreatic beta cell function before and after withholding DTG. We demonstrated that he was phenotypically different from the reported cases of accelerated hyperglycemia and he continued to have worsening insulin resistance despite withholding DTG. His blood glucose improved with dietary T2DM management. It is possible he had an inherent risk of developing T2DM independent of his exposure to DTG. This put in question whether DTG should universally be withheld in PLHIV with incident T2DM in Uganda.

Dolutegravir use over 48 weeks is not associated with worsening insulin resistance and pancreatic beta cell function in a cohort of HIV-infected Ugandan adults.

BACKGROUND: The Uganda Ministry of Health issued restrictive guidelines on the use of dolutegravir (DTG) in persons stratified to have a heightened risk of diabetes mellitus. This followed multiple reports of persons with HIV (PWH) presenting with accelerated hyperglycemia after a few weeks to months of exposure to DTG. Having demonstrated a low incidence of diabetes mellitus and improving blood glucose trajectories in a cohort of ART naïve Ugandan PWH on DTG, we sought to determine whether the observed improvement in blood glucose did not mask background compensated insulin resistance. METHODS: In this analysis, 63 patients underwent serial oral glucose tolerance tests over 48 weeks. Using fasting serum insulin and glucose, we calculated insulin resistance and pancreatic beta cell function by homeostatic modelling (HOMA IR and HOMA%ß respectively). Absolute mean changes between baseline and post-baseline blood glucose, pancreatic beta cell function and insulin resistance were computed by subtracting each post-baseline value from the baseline value and compared using student t-test. Multiple linear regression models were used to determine the factors associated with changes in pancreatic beta cell function and insulin resistance. RESULTS: Of the 63 participants, 37 (58%) were female. Median age was 31 (IQR: 28-37). Despite a trend towards an initial increase in both HOMA IR and HOMA%ß at 12 weeks followed by a decline through 36 weeks to 48 weeks, the HOMA IR and HOMA%ß at 48 weeks were not significantly different from baseline i.e. (difference in mean HOMA IR from baseline: 0.14, 95%CI: -0.46, 0.733, p = 0.648) and (difference in mean HOMA %ß from baseline: 6.7, 95%CI: -13.4, 26.8, p = 0.506) respectively. CONCLUSION: We demonstrated insignificant changes in both insulin resistance and pancreatic beta cell function in clinically stable young adult Ugandan PWH on dolutegravir for 48 weeks. We add to the body of evidence demonstrating glucose metabolic safety of dolutegravir in ART naïve patients. Ugandan guidelines should reconsider restricting DTG initiation in ART naive adults at high risk for diabetes.

Blood glucose outcomes of anti-retroviral therapy naïve Ugandan people with HIV with pre-diabetes mellitus initiated on dolutegravir for 48 weeks.

Background: The Uganda ministry of Health recommends frequent blood glucose monitoring for the first six months on dolutegravir, in people with HIV (PWH) having pre-diabetes mellitus (pre-DM). We sought to determine if indeed PWH with pre-diabetes started on dolutegravir had worse blood glucose outcomes at 48 weeks compared to those with normal blood glucose. Methods: In this matched cohort study, we compared 44 PWH with pre-DM and 88 PWH with normal blood glucose at baseline. The primary outcome was change in mean fasting blood glucose (FBG) from baseline to week 48 and 2-hour blood glucose (2hBG) from baseline to week 36 compared between the two groups. Results: There was significant increase in FBG in PWH with normal blood glucose (mean change in FBG(FBG): 3.9mg/dl, 95% confidence interval (95% CI): (2.2, 5.7), p value (p) = < 0.0001) and decrease in those with pre-DM (FBG: -6.1mg/dl, 95%CI (-9.1, -3.2), p = < 0.0001) at 48 weeks. 2hBG at 36 weeks was significantly lower than at baseline in both groups with the magnitude of reduction larger in those with pre-DM at 12 weeks (adjusted differences in mean drop in 2hBG (a2hBG): -19.69mg/dl, 95%CI (-30.19, -9.19), p = < 0.0001) and 36 weeks (a2hBG: -19.97mg/dl, 95%CI (-30.56, -9.39), p = < 0.0001). Conclusion: We demonstrated that Ugandan ART naïve PWH with pre-diabetes at enrollment have consistent improvement in both fasting blood glucose and glucose tolerance over 48 weeks on dolutegravir. Intensified blood glucose monitoring of these patients in the first six months of dolutegravir may be unnecessary.

Dolutegravir use over 48 weeks is not associated with worsening insulin resistance and pancreatic beta cell function in a cohort of HIV-infected Ugandan adults.

Background The Uganda Ministry of Health issued restrictive guidelines on the use of dolutegravir (DTG) in persons stratified to have a heightened risk of diabetes mellitus. This followed multiple reports of persons with HIV (PWH) presenting with accelerated hyperglycemia after a few weeks to months of exposure to DTG. Having demonstrated a low incidence of diabetes mellitus and improving blood glucose trajectories in a cohort of ART naïve Ugandan PWH on DTG, we sought to determine whether the observed improvement in blood glucose did not mask background compensated insulin resistance. Methods In this analysis, 63 patients underwent serial oral glucose tolerance tests over 48 weeks. Using fasting serum insulin and glucose, we calculated insulin resistance and pancreatic beta cell function by homeostatic modelling (HOMA IR and HOMA%ß respectively). Absolute mean changes between baseline and post-baseline blood glucose, pancreatic beta cell function and insulin resistance were computed by subtracting each post-baseline value from the baseline value and compared using student t-test. Multiple linear regression models were used to determine the factors associated with changes in pancreatic beta cell function and insulin resistance. Results Of the 63 participants, 37 (58%) were female. Median age was 31 (IQR: 28-37). Despite a trend towards an initial increase in both HOMA IR and HOMA%ß at 12 weeks followed by a decline through 36 weeks to 48 weeks, the HOMA IR and HOMA%ß at 48 weeks were not significantly different from baseline i.e. (difference in mean HOMA IR from baseline: 0.14, 95%CI: -0.46, 0.733, p = 0.648) and (difference in mean HOMA %ß from baseline: 6.7, 95%CI: -13.4, 26.8, p = 0.506) respectively.

Prevalence of Cardiometabolic Disease Risk Factors in People With HIV Initiating Antiretroviral Therapy at a High-Volume HIV Clinic in Kampala, Uganda.

Background: Cardiometabolic diseases are a leading cause of HIV-related morbidity and mortality, yet routine screening is not undertaken in high-burden countries. We aimed to assess the prevalence and risk factors of the metabolic syndrome (MetS) and its components in adult Ugandan people with HIV (PWH) initiating dolutegravir-based antiretroviral therapy (ART). Methods: We conducted a cross-sectional study using baseline sociodemographic and clinical data of PWH aged ≥18 years enrolled in the Glucose metabolism changes in Ugandan HIV patients on Dolutegravir (GLUMED) study from January to October 2021. MetS was defined as having ≥3 of the following: abdominal obesity, hypertension (HTN), hyperglycemia, elevated triglycerides, and low high-density lipoprotein cholesterol. Multiple logistic regression was used to assess associations between potential risk factors and MetS and its components. Results: Three hundred nine PWH were analyzed (100% ART-naïve, 59.2% female, median age 31 years, and median CD4 count 318 cells/mm3). The prevalence of MetS was 13.9%. The most common cardiometabolic condition was dyslipidemia (93.6%), followed by abdominal obesity (34.0%), hyperglycemia (18.4%), and HTN (8.1%). In adjusted analysis, MetS was associated with age >40 years (adjusted odds ratio [aOR], 3.33; 95% CI, 1.45-7.67) and CD4 count >200 cells/mm3 (aOR, 3.79; 95% CI, 1.23-11.63). HTN was associated with age >40 years (aOR, 2.96; 95% CI, 1.32-6.64), and dyslipidemia was associated with urban residence (aOR, 4.99; 95% CI, 1.35-18.53). Conclusions: Cardiometabolic risk factors were common in this young Ugandan cohort of PWH initiating dolutegravir-based ART, underscoring the need for programmatic implementation of surveillance and management of comorbidities in Uganda and similar settings.

Blood glucose trajectories and incidence of diabetes mellitus in Ugandan people living with HIV initiated on dolutegravir.

BACKGROUND: Following reports of anti-retroviral therapy (ART) experienced Ugandan people living with HIV (PLHIV) presenting with diabetic ketoacidosis weeks to months following a switch to dolutegravir (DTG), the Uganda Ministry of Health recommended withholding DTG in both ART naïve and experienced PLHIV with diabetes mellitus (T2DM), as well as 3-monthly blood glucose monitoring for patients with T2DM risk factors. We sought to determine if the risk of T2DM is indeed heightened in nondiabetic ART naïve Ugandan PLHIV over the first 48 weeks on DTG. METHODS: Between January and October 2021, 243 PLHIV without T2DM were initiated on DTG based ART for 48 weeks. Two-hour oral glucose tolerance tests (2-h OGTT) were performed at baseline, 12, and 36 weeks; fasting blood glucose (FBG) was measured at 24 and 48 weeks. The primary outcome was the incidence of T2DM. Secondary outcomes included: incidence of pre-Diabetes Mellitus (pre-DM), median change in FBG from baseline to week 48 and 2-h blood glucose (2hBG) from baseline to week 36. Linear regression models were used to determine adjusted differences in FBG and 2hBG from baseline to weeks 48 and 36 respectively. RESULTS: The incidence of T2DM was 4 cases per 1000 PY (1/243) and pre-DM, 240 cases per 1000 person years (PY) (54/243). There was a significant increase in FBG from baseline to week 48 [median change from baseline (FBG): 3.6 mg/dl, interquartile range (IQR): - 3.6, 7.2, p-value (p) = 0.005] and significant reduction in 2hBG (2hBG: - 7.26 mg/dl, IQR: - 21.6, 14.4, p = 0.024) at week 36. A high CD4 count and increased waist circumference were associated with 2hBG increase at week 36. CONCLUSION: We demonstrated a low incidence of T2DM in Ugandan ART-naïve patients receiving DTG. We also demonstrated that longitudinal changes in BG were independent of conventional risk factors of T2DM in the first 48 weeks of therapy. Restricting the use of dolutegravir in Ugandan ART naïve patients perceived to be high risk for diabetes mellitus may be unwarranted.

Association between integrase strand transfer inhibitor use with insulin resistance and incident diabetes mellitus in persons living with HIV: a systematic review and meta-analysis.

Whether integrase strand transfer inhibitors (INSTIs) are associated with a higher risk of incident type 2 diabetes mellitus (DM) than other antiretroviral therapies (ART) needs to be established.MEDLINE, Embase, Web of Science, and ClinicalTrials.gov registries were searched for studies published between 1 January 2000 and 15 June 2022. Eligible studies reported incident DM or mean changes in insulin resistance measured by Homeostatic Model for Insulin Resistance (HOMA-IR) in patients on INSTIs compared with other ARTs. We performed random-effects meta-analyses to obtain pooled relative risks (RRs) with 95% CIs.A total of 16 studies were pooled: 13 studies meta-analyzed for incident diabetes with a patient population of 72 404 and 3 for changes in HOMA-IR. INSTI therapy was associated with a lower risk of incident diabetes in 13 studies (RR 0.80, 95% CI 0.67 to 0.96, I2=29%), of which 8 randomized controlled trials demonstrated a 22% reduced risk (RR 0.88, 95% CI 0.81 to 0.96, I2=0%). INSTIs had a lower risk compared with non-nucleoside reverse transcriptase inhibitors (RR 0.75, 95% CI 0.63 to 0.89, I2=0%) but similar to protease inhibitor-based therapy (RR 0.78, 95% CI 0.61 to 1.01, I2=27%). The risk was lower in studies with longer follow-up (RR 0.70, 95% CI 0.53 to 0.94, I2=24%) and among ART-naïve patients (RR 0.78, 95% CI 0.65 to 0.94, I2=3%) but increased in African populations (RR 2.99, 95% CI 2.53 to 3.54, I2=0%).In conclusion, exposure to INSTIs was not associated with increased risk of DM, except in the African population. Stratified analyses suggested reduced risk among ART-naïve patients and studies with longer follow-up.International Prospective Register of Systematic Reviews (PROSPERO) registration number: CRD42021273040.

Effects of Isocaloric Fructose Restriction on Ceramide Levels in Children with Obesity and Cardiometabolic Risk: Relation to Hepatic De Novo Lipogenesis and Insulin Sensitivity.

Sugar intake, particularly fructose, is implicated as a factor contributing to insulin resistance via hepatic de novo lipogenesis (DNL). A nine-day fructose reduction trial, controlling for other dietary factors and weight, in children with obesity and metabolic syndrome, decreased DNL and mitigated cardiometabolic risk (CMR) biomarkers. Ceramides are bioactive sphingolipids whose dysregulated metabolism contribute to lipotoxicity, insulin resistance, and CMR. We evaluated the effect of fructose reduction on ceramides and correlations between changes observed and changes in traditional CMR biomarkers in this cohort. Analyses were completed on data from 43 participants. Mean weight decreased (-0.9 ± 1.1 kg). The majority of total and subspecies ceramide levels also decreased significantly, including dihydroceramides, deoxyceramides and ceramide-1-phoshates. Change in each primary ceramide species correlated negatively with composite insulin sensitivity index (CISI). Change in deoxyceramides positively correlated with change in DNL. These results suggest that ceramides decrease in response to dietary fructose restriction, negatively correlate with insulin sensitivity, and may represent an intermediary link between hepatic DNL, insulin resistance, and CMR.

Association between integrase strand transfer inhibitor (INSTIs) use with insulin resistance and incident diabetes mellitus in persons living with HIV: A systematic review and meta-analysis protocol.

INTRODUCTION: Poeple living with HIV have higher prevalence of diabetes mellitus and metabolic perturbations compared to non-HIV populations. Diabetes and metabolic syndrome co-morbidities add significant burden to HIV care. Currently, WHO recommends integrase strand transfer inhibitors (INSTIs) as the first or second line therapy in people with HIV due to overall good tolerability and safety profile. However, whether INSTI use increases the risk of incident diabetes (with or without metabolic syndrome) compared to other anti-retroviral therapies (ART) is controversial. In this systematic review and meta-analysis, we aim to examine this risk in HIV-positive populations receiving INSTIs compared to other ART regimens (not containing INSTIs). METHODS AND ANALYSIS: The study will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement and the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. This protocol adheres to the Standard Protocol Items for reporting systematic reviews and meta-analyses checklist. Eligibility criteria will be original peer-reviewed published articles and conference abstracts with no language or geographical restriction; that report the ocurrence of diabetes mellitus as a discrete outcome or part of metabolic syndrome, in adult PLWHIV receiving INSTIs compared to other ART regimens. PubMed/ Medline, Web of Science, Embase and Cochrane Database of Systematic Reviews will be searched from 1st- January-2000 to 31st-January-2022. Per our a priori, screening, inclusion and data extraction will be conducted separately by two investigators, and a senior researcher will be consulted in case of disagreement. The quality of included studies will be assessed by the Newcastle-Ottawa Scale (NOS) for cohort and case-control studies and the revised Cochrane risk-of-bias tool (ROB2) for randomized controlled trials. The quantitative synthesis of the study outcomes will be explored in different subgroups and sensitivity analyses. Meta regression will also be performed to further test the predictors of the outcome. ETHICS AND DISSEMINATION: Ethical approval is waived as the study is a review of published litterature. The analyses will be presented in conferences and published as a scientific article. TRIAL REGISTRARTION: PROSPERO registration number is; CRD42021273040.

Separation of postprandial lipoproteins: improved purification of chylomicrons using an ApoB100 immunoaffinity method.

Elevated levels of triglyceride-rich lipoproteins (TRLs), both fasting and postprandial, are associated with increased risk for atherosclerosis. However, guidelines for treatment are defined solely by fasting lipid levels, even though postprandial lipids may be more informative. In the postprandial state, circulating lipids consist of dietary fat transported from the intestine in chylomicrons (CMs; containing ApoB48) and fat transported from the liver in VLDL (containing ApoB100). Research into the roles of endogenous versus dietary fat has been hindered because of the difficulty in separating these particles by ultracentrifugation. CM fractions have considerable contamination from VLDL (purity, 10%). To separate CMs from VLDL, we produced polyclonal antibodies against ApoB100 and generated immunoaffinity columns. TRLs isolated by ultracentrifugation of plasma were applied to these columns, and highly purified CMs were collected (purity, 90-94%). Overall eight healthy unmedicated adult volunteers (BMI, 27.2 ± 1.4 kg/m2; fasting triacylglycerol, 102.6 ± 19.5 mg/dl) participated in a feeding study, which contained an oral stable-isotope tracer (1-13C acetate). We then used this technique on plasma samples freshly collected during an 8 h human feeding study from a subset of four subjects. We analyzed fractionated lipoproteins by Western blot, isolated and derivatized triacylglycerols, and calculated fractional de novo lipogenesis. The results demonstrated effective separation of postprandial lipoproteins and substantially improved purity compared with ultracentrifugation protocols, using the immunoaffinity method. This method can be used to better delineate the role of dietary sugar and fat on postprandial lipids in cardiovascular risk and explore the potential role of CM remnants in atherosclerosis.

Isocaloric Fructose Restriction Reduces Serum d-Lactate Concentration in Children With Obesity and Metabolic Syndrome.

OBJECTIVE: To investigate the link between dietary sugar consumption and two separate pathogenetic mechanisms associated with metabolic syndrome: de novo lipogenesis (DNL) and nonenzymatic glycation. DESIGN AND PARTICIPANTS: We assessed changes in serum d-lactate (the detoxification end-product of methylglyoxal) concentration in response to 9 days of isocaloric fructose restriction in 20 children with obesity and metabolic syndrome, and examined correlations with changes in DNL, liver fat, insulin sensitivity, and other metrics of hepatic metabolism. INTERVENTIONS: Nine days of dietary sugar restriction, with substitution of equal amounts of refined starch. MAIN OUTCOME MEASURES: On days 0 and 10, children had laboratory evaluation of d-lactate levels and other analytes, and underwent oral glucose tolerance testing, magnetic resonance spectroscopy to quantify fat depots, and 13C-acetate incorporation into triglyceride (TG) to measure DNL. RESULTS: d-Lactate was associated with baseline liver fat fraction (P < 0.001) and visceral adipose tissue (P < 0.001) but not with subcutaneous adipose tissue. At baseline, d-lactate was positively correlated with DNL-area under the curve (AUC) (P = 0.003), liver fat fraction (P = 0.02), TG (P = 0.004), and TG/high-density lipoprotein ratio (P = 0.002). After 9 days of isocaloric fructose restriction, serum d-lactate levels reduced by 50% (P < 0.0001), and changes in d-lactate correlated with both changes in DNL-AUC and measures of insulin sensitivity. CONCLUSION: Baseline correlation of d-lactate with DNL and measures of insulin sensitivity and reduction in d-lactate after 9 days of isocaloric fructose restriction suggest that DNL and nonenzymatic glycation are functionally linked via intermediary glycolysis in the pathogenesis of metabolic syndrome and point to fructose as a key dietary substrate that drives both pathways.

An ethanolic extract of Artemisia scoparia inhibits lipolysis in vivo and has antilipolytic effects on murine adipocytes in vitro.

An ethanolic extract of Artemisia scoparia (SCO) has metabolically favorable effects on adipocyte development and function in vitro and in vivo. In diet-induced obese mice, SCO supplementation significantly reduced fasting glucose and insulin levels. Given the importance of adipocyte lipolysis in metabolic health, we hypothesized that SCO modulates lipolysis in vitro and in vivo. Free fatty acids and glycerol were measured in the sera of mice fed a high-fat diet with or without SCO supplementation. In cultured 3T3-L1 adipocytes, the effects of SCO on lipolysis were assessed by measuring glycerol and free fatty acid release. Microarray analysis, qPCR, and immunoblotting were used to assess gene expression and protein abundance. We found that SCO supplementation of a high-fat diet in mice substantially reduces circulating glycerol and free fatty acid levels, and we observed a cell-autonomous effect of SCO to significantly attenuate tumor necrosis factor-α (TNFα)-induced lipolysis in cultured adipocytes. Although several prolipolytic and antilipolytic genes were identified by microarray analysis of subcutaneous and visceral adipose tissue from SCO-fed mice, regulation of these genes did not consistently correlate with SCO's ability to reduce lipolytic metabolites in sera or cell culture media. However, in the presence of TNFα in cultured adipocytes, SCO induced antilipolytic changes in phosphorylation of hormone-sensitive lipase and perilipin. Together, these data suggest that the antilipolytic effects of SCO on adipose tissue play a role in the ability of this botanical extract to improve whole body metabolic parameters and support its use as a dietary supplement to promote metabolic resiliency.

Dietary carbohydrates and fatty liver disease: de novo lipogenesis.

PURPOSE OF REVIEW: To review recent evidence for the role of dietary carbohydrate in de novo lipogenesis (DNL) and nonalcoholic fatty liver disease (NAFLD). RECENT FINDINGS: A large body of evidence suggests that increased hepatic DNL is a significant pathway contributing to the development of NAFLD. Dietary carbohydrates, in particular, fructose, have been shown to stimulate DNL and increase liver fat, although it is debated whether this is due to excess energy or fructose per se. Recent dietary intervention studies conducted in energy balance show that high-fructose diets increase DNL and liver fat, whereas fructose restriction decreases DNL and liver fat. SUMMARY: The association of high-carbohydrate and high-sugar diets with NAFLD may in part be explained by the effect of sugar on increasing hepatic DNL.

Conversion of Sugar to Fat: Is Hepatic de Novo Lipogenesis Leading to Metabolic Syndrome and Associated Chronic Diseases?

Epidemiologic studies suggest a link between excess sugar consumption and obesity, fatty liver disease, metabolic syndrome, and type 2 diabetes mellitus. One important pathway that may link these metabolic diseases to sugar consumption is hepatic conversion of sugar to fat, a process known as de novo lipogenesis (DNL). Mechanistic studies have shown that diets high in simple sugars increase both DNL and liver fat. Importantly, removal of sugar from diets of children with obesity for only 9 days consistently reduced DNL and liver fat and improved glucose and lipid metabolism. Although the sugar and beverage industries continue to question the scientific evidence linking high-sugar diets to metabolic diseases, major health organizations now make evidence-based recommendations to limit consumption of simple sugars to no more than 5% to 10% of daily intake. Clear recommendation about moderating sugar intake to patients may be an important nonpharmacologic tool to include in clinical practice.

Effects of Dietary Fructose Restriction on Liver Fat, De Novo Lipogenesis, and Insulin Kinetics in Children With Obesity.

BACKGROUND & AIMS: Consumption of sugar is associated with obesity, type 2 diabetes mellitus, nonalcoholic fatty liver disease, and cardiovascular disease. The conversion of fructose to fat in liver (de novo lipogenesis [DNL]) may be a modifiable pathogenetic pathway. We determined the effect of 9 days of isocaloric fructose restriction on DNL, liver fat, visceral fat (VAT), subcutaneous fat, and insulin kinetics in obese Latino and African American children with habitual high sugar consumption (fructose intake >50 g/d). METHODS: Children (9-18 years old; n = 41) had all meals provided for 9 days with the same energy and macronutrient composition as their standard diet, but with starch substituted for sugar, yielding a final fructose content of 4% of total kilocalories. Metabolic assessments were performed before and after fructose restriction. Liver fat, VAT, and subcutaneous fat were determined by magnetic resonance spectroscopy and imaging. The fractional DNL area under the curve value was measured using stable isotope tracers and gas chromatography/mass spectrometry. Insulin kinetics were calculated from oral glucose tolerance tests. Paired analyses compared change from day 0 to day 10 within each child. RESULTS: Compared with baseline, on day 10, liver fat decreased from a median of 7.2% (interquartile range [IQR], 2.5%-14.8%) to 3.8% (IQR, 1.7%-15.5%) (P < .001) and VAT decreased from 123 cm3 (IQR, 85-145 cm3) to 110 cm3 (IQR, 84-134 cm3) (P < .001). The DNL area under the curve decreased from 68% (IQR, 46%-83%) to 26% (IQR, 16%-37%) (P < .001). Insulin kinetics improved (P < .001). These changes occurred irrespective of baseline liver fat. CONCLUSIONS: Short-term (9 days) isocaloric fructose restriction decreased liver fat, VAT, and DNL, and improved insulin kinetics in children with obesity. These findings support efforts to reduce sugar consumption. ClinicalTrials.gov Number: NCT01200043.

Short-term isocaloric fructose restriction lowers apoC-III levels and yields less atherogenic lipoprotein profiles in children with obesity and metabolic syndrome.

BACKGROUND AND AIMS: Dietary fructose may play a role in the pathogenesis of metabolic syndrome (MetS). In a recently published study of obese children with MetS, we showed that isocaloric fructose restriction reduced fasting triglyceride (TG) and LDL-cholesterol (LDL-C). In these ancillary analyses, we tested the hypothesis that these effects were also accompanied by improved quantitative and qualitative changes in LDL and HDL subclasses and their apolipoproteins; as well as change in VLDL, particularly apoC-III. METHODS: Obese children with MetS (n = 37) consumed a diet that matched self-reported macronutrient composition for nine days, with the exception that dietary fructose was reduced from 11.7 ± 4.0% to 3.8 ± 0.5% of daily calories and substituted with glucose (in starch). Participants underwent fasting biochemical analyses on Days 0 and 10. HDL and LDL subclasses were analyzed using the Lipoprint HDL and LDL subfraction analysis systems from Quantimetrix. RESULTS: Significant reductions in apoB (78 ± 24 vs. 66 ± 24 mg/dl) apoC-III (8.7 ± 3.5 vs. 6.5 ± 2.6 mg/dl) and apoE (4.6 ± 2.3 vs. 3.6 ± 1.1 mg/dl), all p < 0.001) were observed. LDL size increased by 0.87 Å (p = 0.008). Small dense LDL was present in 25% of our cohort and decreased by 68% (p = 0.04). Small HDL decreased by 2.7% (p < 0.001) and large HDL increased by 2.4% (p = 0.04). The TG/HDL-C ratio decreased from 3.1 ± 2.5 to 2.4 ± 1.4 (p = 0.02). These changes in fasting lipid profiles correlated with changes in insulin sensitivity. CONCLUSIONS: Isocaloric fructose restriction for 9 days improved lipoprotein markers of CVD risk in children with obesity and MetS. The most dramatic reduction was seen for apoC-III, which has been associated with atherogenic hypertriglyceridemia.

In vivo triglyceride synthesis in subcutaneous adipose tissue of humans correlates with plasma HDL parameters.

BACKGROUNDS AND AIMS: Low concentrations of plasma HDL-C are associated with the development of atherosclerotic cardiovascular diseases and type 2 diabetes. Here we aimed to explore the relationship between the in vivo fractional synthesis of triglycerides (fTG) in subcutaneous (s.q.) abdominal adipose tissue (AT), HDL-C concentrations and HDL particle size composition in non-diabetic humans. METHODS: The fTG in s.q. abdominal AT was measured in 16 non-diabetic volunteers (7 women, 9 men; Age: 49 ± 20 years; BMI: 31 ± 5 kg/m; Fasting Plasma Glucose: 90 ± 10 mg/dl) after (2)H2O labeling. HDL-C concentration and subclasses, large (L-HDL), intermediate (I-HDL) and small (S-HDL) were measured. RESULTS: Linear regression analyses demonstrated significant associations of fTG with plasma concentration of HDL-C (r = 0.625,p = 0.009) and percent contribution of L-HDL (r = 0.798,p < 0.001), I-HDL (r = -0.765,p < 0.001) and S-HDL (r = -0.629, p = 0.009). When analyses were performed by gender, the associations remained significant in women (HDL-C: r = 0.822,p = 0.023; L-HDL: r = 0.892,p = 0.007; I-HDL: r = -0.927,p = 0.003) but not men. CONCLUSIONS: Our study demonstrated an in vivo association between subcutaneous abdominal adipose tissue lipid dynamics and HDL parameters in humans, but this was true for women not men. Positive association with L-HDL and negative with I-HDL suggest that subcutaneous abdominal adipose tissue lipid dynamics may play an important role in production of mature functional HDL particles. Further studies evaluating the mechanism responsible for these associations and the observed gender differences are important and warranted to identify potential novel targets of intervention to increase the production of atheroprotective subclasses of HDL-Cs and thus decreasing the risks of development of atherosclerotic conditions.