Biosynthesis and bioavailability of long-chain polyunsaturated fatty acids in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has a high occurrence in most countries. Recent studies estimate its prevalence to be near 30% in United States, Italian and Japanese general adult populations. NAFLD commonly presents along with obesity and insulin resistance (IR), pathologies that share with NAFLD metabolic and inflammatory components. These conditions, particularly NAFLD, are associated with alterations in the bioavailability of long-chain polyunsaturated fatty acids (LCPUFAs). In the human population, the bioavailability of LCPUFAs depends both on endogenous biosynthesis and diet amount of preformed LCPUFAs. However, the lower liver LCPUFAs product/precursor ratio namely (20:5n?3 + 22:6n?3)/18:3n?3, 20:4n?6/18:2n?6 present in common Western diets, makes critical an adequate pathway activity to ensure minimum bioavailability of LCPUFAs in most Western populations. The key step of this biosynthesis involves Δ5 and Δ6-desaturases, whose activities are altered in NAFLD. During the disease, the presence of molecular activators of these two enzymes does not correlate with the scarce LCPUFAS biosynthesis observed. The key to this apparent contradiction, or at least part of it, could be explained on the basis of the possible sensitivity of the desaturases to oxidative stress; a metabolic condition strongly linked to inflammatory pathologies such as NAFLD, obesity and IR and that, according to latest research, not only would be consequence but also possibly a cause of these diseases. The present review is focused on the relationship between NAFLD and the bioavailability of LCPUFAs, with special reference to the role that oxidative stress could play in the modulation of the liver fatty acid desaturase activity.     

Obstructive Sleep Apnea Predisposes to Nonalcoholic Fatty Liver Disease in Patients with Polycystic Ovary Syndrome

ObjectiveSome studies have shown a higher prevalence of nonalcoholic fatty liver disease (NAFLD) and obstructive sleep apnea (OSA) in patients with polycystic ovary syndrome (PCOS). The objective of this study was to assess NAFLD in PCOS women with and without OSA. A possible role of high serum androgen levels in the development of OSA in PCOS women was also investigated.MethodsBiochemical, hormonal, and polysomnography parameters were determined in 38 premenopausal PCOS patients. NAFLD was evaluated by ultrasound. Testosterone was measured by an immunoassay.ResultsSerum androgen levels and the prevalence of NAFLD (83.3% vs. 26.9%; P < .001) were higher in patients with OSA than those without OSA. The mean apnea-hypopnea index (AHI) was higher in patients with NAFLD than in those without NAFLD (16.87 events [ev]/h vs. 1.57 ev/h; P < .002). On multivariate logistic regression, where body mass index ≥ 30 kg/m², homeostasis model assessment for insulin resistance ≥ 2.7, and OSA (AHI ≥ 5 ev/h) were independent variables, only OSA was an independent predictor of NAFLD (odds ratio [OR], 7.63; P = .044). Free testosterone levels ≥ 1.07 ng/dL were also independently associated with OSA (OR, 8.18; P = .023).ConclusionIn PCOS women, the occurrence of OSA strongly predisposes them to development of NAFLD and a worse metabolic profile; hence, treatment of OSA might be beneficial for NAFLD. (Endocr Pract. 2014;20:244-251)     

Cellular cholesterol accumulation modulates high fat high sucrose (HFHS) diet-induced ER stress and hepatic inflammasome activation in the development of non-alcoholic steatohepatitis

Non-alcoholic steatohepatitis (NASH), is the form of non-alcoholic fatty liver disease posing risk to progress into serious long term complications. Human and pre-clinical models implicate cellular cholesterol dysregulation playing important role in its development. Mouse model studies suggest synergism between dietary cholesterol and fat in contributing to NASH but the mechanisms remain poorly understood. Our laboratory previously reported the primary importance of hepatic endoplasmic reticulum cholesterol (ER-Chol) in regulating hepatic ER stress by comparing the responses of wild type, Ldlr −/− xLcat +/+ and Ldlr −/− xLcat −/− mice, to a 2% high cholesterol diet (HCD). Here we further investigated the roles of ER-Chol and ER stress in HFHS diet-induced NASH using the same strains. With HFHS diet feeding, both WT and Ldlr −/− xLcat +/+ accumulate ER-Chol in association with ER stress and inflammasome activation but the Ldlr −/− xLcat −/− mice are protected. By contrast, all three strains accumulate cholesterol crystal, in correlation with ER-Chol, albeit less so in Ldlr −/− xLcat −/− mice. By comparison, HCD feeding per se (i) is sufficient to promote steatosis and activate inflammasomes, and (ii) results in dramatic accumulation of cholesterol crystal which is linked to inflammasome activation in Ldlr −/− xLcat −/− mice, independent of ER-Chol. Our data suggest that both dietary fat and cholesterol each independently promote steatosis, cholesterol crystal accumulation and inflammasome activation through distinct but complementary pathways. In vitro studies using palmitate-induced hepatic steatosis in HepG2 cells confirm the key roles by cellular cholesterol in the induction of steatosis and inflammasome activations. These novel findings provide opportunities for exploring a cellular cholesterol-focused strategy for treatment of NASH.     

Activation of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase during high fat diet feeding

The liver plays a central role in regulating cholesterol homeostasis. High fat diets have been shown to induce obesity and hyperlipidemia. Despite considerable advances in our understanding of cholesterol metabolism, the regulation of liver cholesterol biosynthesis in response to high fat diet feeding has not been fully addressed. The aim of the present study was to investigate mechanisms by which a high fat diet caused activation of liver 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) leading to increased cholesterol biosynthesis. Mice were fed a high fat diet (60% kcal fat) for 5 weeks. High fat diet feeding induced weight gain and elevated lipid levels (total cholesterol and triglyceride) in both the liver and serum. Despite cholesterol accumulation in the liver, there was a significant increase in hepatic HMG-CoA reductase mRNA and protein expression as well as enzyme activity. The DNA binding activity of sterol regulatory element binding protein (SREBP)-2 and specific protein 1 (Sp1) were also increased in the liver of mice fed a high fat diet. To validate the in vivo findings, HepG2 cells were treated with palmitic acid. Such a treatment activated SREBP-2 as well as increased the mRNA and enzyme activity of HMG-CoA reductase leading to intracellular cholesterol accumulation. Inhibition of Sp1 by siRNA transfection abolished palmitic acid-induced SREBP-2 and HMG-CoA reductase mRNA expression. These results suggest that Sp1-mediated SREBP-2 activation contributes to high fat diet induced HMG-CoA reductase activation and increased cholesterol biosynthesis. This may play a role in liver cholesterol accumulation and hypercholesterolemia.     

Dysregulation Of The Hypothalamic-Pituitary-Adrenal Axis Increases Central Body Fat Accumulation In Males Affected By Diabetes Mellitus And Late-Onset Hypogonadism

Objective: Functional hypercortisolism (FH) is a condition which occurs in some clinical states, such as major depression, eating disorders, numerous psychiatric conditions, and diabetes mellitus (DM) and which exerts several negative systemic effects. No data exist on the potentially harmful role of FH on body composition. In this retrospective study, we evaluated the influence of hypothalamic-pituitary-adrenal (HPA) axis dysregulation on body composition in men affected by DM-associated late-onset hypogonadism (LOH).Methods: Fourteen subjects affected by FH (FH-LOH) and 18 subjects not affected (N-LOH) were studied. Clinical, hormonal, and body composition measures were considered.Results: The 2 groups had comparable age and weight. FH-LOH patients had lower levels of total (2 ± 0.27 ng/mL versus 2.31 ± 0.26 ng/mL; P = .003) and free (39.5 ± 6.44 pg/mL versus 46.8 ± 7.23 pg/mL; P = .005) (median, 38.7 &lsqb;interquartile range, 36.1 to 41.3] pg/mL versus median, 46.1 &lsqb;interquartile range, 40.4 to 52.7] pg/mL) testosterone compared to N-LOH patients. Abdominal fat amount was greater in FH-LOH than in N-LOH patients, even after adjustment for total testosterone. None of the bivariate correlations between body composition measures and hormonal variables were significant in N-LOH. Conversely, in FH-LOH, cortisol area under the curve (AUC) was found to be positively and significantly correlated with trunk (r = 0.933; P<.001) and abdominal fat (r = 0.852; P<.001) and negatively with lean leg (r = -0.607; P = .021). All of these associations were further confirmed upon linear regression analysis in FH-LOH (respectively, unstandardized β = 10.988 &lsqb;P<.001]; β = 1.156 &lsqb;P<.001]; β = -7.675 &lsqb;P = .021]). Multivariate regression analysis confirmed AUC cortisol as a predictor of trunk and abdominal fat in FH-LOH.Conclusion: Dysregulation of the HPA axis in LOH-associated DM seems to be involved in abdominal fat accumulation.Abbreviations:ACTH = adrenocorticotropic hormoneAUC = area under the curveCRH = corticotropin-releasing hormoneCT = computed tomographyDEXA = dual-energy X-ray absorptiometryDM = diabetes mellitusFH = functional hypercortisolismFH-LOH = subjects affected by functional hypercortisolismFSH = follicle-stimulating hormoneHPA = hypothalamic-pituitary-adrenalLH = luteinizing hormoneLOH = late-onset hypogonadismN-LOH = subjects not affected by functional hypercortisolismOST = overnight low-dose dexamethasone suppression testSHBG = sex hormone–binding globulinUFC = urinary free cortisol     

Nonfunctioning Adrenal Incidentalomas are not Clinically Silent: A Longitudinal Cohort Study

Objective: The association between nonfunctioning adrenal incidentalomas (NFAIs) and cardiometabolic diseases remains controversial. This retrospective cohort study investigated whether NFAIs are related with prevalent and incident cardiometabolic diseases.Methods: This study included 154 patients with biochemically confirmed NFAIs and 1:3 age and sex-matched controls without adrenal incidentalomas (n = 462) among subjects who underwent abdominal computed tomography at a single healthcare center in 2003–2012. Electronic medical records were reviewed for comorbidities at baseline and during a mean follow-up of 7.5 years. The logistic regression analysis for prevalent cardiometabolic diseases and the survival analysis for incident cardiometabolic diseases were performed.Results: The subjects were 55.7 ± 8.8 years of age and predominantly male (73.1%). The NFAI group had a higher body mass index compared to the age and sex-matched control group (25.1 ± 2.8 vs. 24.0 ± 2.8 kg/m²; P<.001). In a cross-sectional design, covariate-adjusted logistic regression showed significantly higher odds ratios (ORs) for diabetes mellitus and hypertension in the NFAI group (adjusted OR [95% confidence interval [CI]], 1.89 [1.17 to 3.06] and 2.26 [1.47 to 3.50], respectively). The NFAI group had a 2-fold higher risk of insulin resistance (adjusted ORs [95% CI], 2.03 [1.06 to 3.90]). Moreover, NFAI subjects with diabetes mellitus had a greater increase in size of adrenal lesions than those without diabetes mellitus (3.4 ± 5.5 vs. 1.4 ± 5.5 mm; P =.048). However, in the survival analysis, the incidence of any cardiometabolic diseases did not differ between the NFAI and control groups.Conclusion: NFAIs are related to prevalent diabetes mellitus or hypertension in our cross-sectional study. However, the presence of NFAIs did not affect the development of cardiometabolic diseases.Abbreviations: ACTH = adrenocorticotropic hormone; AI = adrenal incidentaloma; BMI = body mass index; CI = confidence interval; CT = computed tomography; HbA1c = hemoglobin A1c; HOMA-IR = homeostasis model assessment of insulin resistance; HU = Hounsfield units; MACE = mild autonomous cortisol excess; NFAI = nonfunctioning adrenal incidentaloma; OR = odds ratio     

Clinical Profile of Nonalcoholic Fatty Liver Disease Among Young Patients With Type 1 Diabetes Mellitus Seen at a Diabetes Speciality Center in India

ObjectiveTo estimate the prevalence and clinical profile of nonalcoholic fatty liver disease (NAFLD) among young type 1 diabetes mellitus (T1DM) patients at a tertiary care diabetes center in India.MethodsElectronic medical records of T1DM patients (age at first diagnosis of T1DM ≤ 25 years) registered between January 1992 and May 2013 who had undergone ultrasonography and denied history of any alcohol intake (n = 736) were reviewed. NAFLD was diagnosed if there was any degree of fatty liver. Retinopathy was initially assessed by direct and indirect ophthalmoscopy and later by retinal photography. Nephropathy was diagnosed if urine protein excretion was > 500 mg/day, and neuropathy was diagnosed if a patient’s vibration perception threshold on biothesiometry was ≥ 20 V.ResultsA total of 204/736 (27.7%) T1DM patients had NAFLD. Compared to T1DM subjects without NAFLD those with NAFLD had higher body mass index (BMI) (18.9 ± 4.2 vs. 20.2 ± 4.7 kg/m², P < .001), waist circumference (67.9 ± 13.2 vs. 71.9 ± 13.3 cm, P < .05), systolic blood pressure (110 ± 15 vs. 116 ± 18 mm Hg, P < .001) and diastolic blood pressure (72 ± 9 vs. 74 ± 10 mm Hg, P < .05), while fasting blood glucose (201 ± 101 vs. 183 ± 101 mg/dL, P < .05) and alkaline phosphatase (419 [12.5] vs. 315 [15.8], P < .001) levels were lower in patients with T1DM with NAFLD. Multiple logistic regression analysis showed a significant association between NAFLD and retinopathy (odds ratio [OR]: 2.01, 95% confidence interval [CI]: 1.13-3.43; P = .017, after adjusting for sex, duration of diabetes, overweight/obesity, hypertension, fasting plasma glucose, nephropathy, and nephropathy (OR: 1.89, 95% CI: 1.02-3.50; P = .042), after adjusting for sex and fasting plasma glucose.ConclusionsThis study suggests that NAFLD is also seen among T1DM patients and that it has an independent and significant association with retinopathy and nephropathy. (Endocr Pract. 2014;20:1249-1257)     

Decreased Inpatient Mortality in Obese Patients With Abdominal Nets

ObjectiveNeuroendocrine tumors (NETs) of the abdomen are rare tumors with an incidence of 3.56 per 100,000 in the general population. Obesity is a growing public health problem with varying effects on the severities of other diseases. We investigated the association between obesity and inpatient morbidity/mortality in patients with abdominal NETs utilizing the Nationwide Inpatient Sample (NIS).MethodsWe analyzed data from the NIS database to investigate the association between obesity and abdominal NETs using patient information from 22,096 patient discharges from January 1, 2009 to December 31, 2010.ResultsWe demonstrate that obesity is strongly associated with decreased rates of inpatient mortality in patients with NET (odds ratio [OR] = 0.6, multivariate P = .02) and that malnutrition is associated with a nearly 5-fold higher risk of inpatient mortality (multivariate P < .0005). We did not find a statistical interaction between obesity and malnutrition; however, patients who were both malnourished and obese had a lower mortality risk than purely malnourished patients.ConclusionsOur data suggests that nutritional status may be an important factor in inpatient mortality in patients with NETs, with obesity being protective. (Endocr Pract. 2014;20:1309-1314)     

Relationship Between the Environmental Endocrine Disruptor Bisphenol a and Dyslipidemia: A Five-Year Prospective Study

Objective: To investigate whether serum bisphenol A (BPA) concentration is related to the occurrence of dyslipidemia.Methods: A total of 574 adults were enrolled at baseline and followed up for 5 years. Concentrations of serum BPA, triglycerides (TGs), low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol were measured. Dyslipidemia was defined as the existence of one or more of the following conditions: high-LDL-cholesterolemia (LDL ≥140 mg/dL), hypertriglyceridemia (TGs ≥150 mg/dL), or low-HDL-cholesterolemia (HDL <40 mg/dL). Participants were stratified into tertiles according to low, median, and high baseline serum BPA levels. Multivariable linear and logistic regression models were used. Data from baseline and follow-up were used for cross-sectional and longitudinal analyses, respectively.Results: In the cross-sectional analysis, compared to subjects in the low BPA tertile, those in the high BPA tertile showed a higher level of LDL cholesterol (108.1 ± 24.4 mg/dL versus 119.5 ± 26.9 mg/dL; P<.05) and a lower level of HDL cholesterol (46.2 ± 11.7 mg/dL versus 39.5 ± 7.5 mg/dL; P<.05). In multivariable linear regression models, Z-transformed BPA was positively associated with LDL cholesterol (β= 0.13, P = .002) and negatively associated with HDL cholesterol (β= -0.28; P<.001). After cross-sectionally adjusting for confounders, subjects in higher BPA exposure was associated with a higher prevalence of low-HDL-cholesterolemia. Longitudinally, in subjects without low-HDL-cholesterolemia at baseline, each SD increment in baseline BPA was associated with a higher incidence of low-HDL-cholesterolemia after adjustment for confounders (odds ratio [95% confidence interval; CI] 2.76, 95% CI 1.21, 6.29).Conclusion: Cross-sectionally, higher BPA exposure is associated with a higher prevalence of low-HDL-cholesterolemia. Longitudinally, baseline BPA is an independent predictor of the 5-year incidence of low-HDL-cholesterolemia.Abbreviations: BMI = body mass index; BPA = bisphenol A; CI = confidence interval; CVD = cardiovascular disease; EIMDS = environment, inflammation and metabolic diseases study; HDL = high density lipoprotein; LDL = low density lipoprotein; OR = odds ratio; PPAR = peroxisome proliferator-activated receptor; SBP = systolic blood pressure; TG = triglyceride; Z-BPA = Z-transformed bisphenol A     

Evaluation of Para- and Perirenal Fat Thickness and its Association with Metabolic Disorders in Polycystic Ovary Syndrome

Objective: The aim of this study was to compare para- and perirenal fat (PFT) and subcutaneous abdominal fat (SFT) measurements between patients with polycystic ovary syndrome (PCOS) and control subjects and to assess the possible relation with metabolic disorders.Methods: This study included 68 patients with PCOS and 40 age- and body mass index (BMI)-matched healthy controls. We evaluated anthropometric, hormonal, and metabolic parameters, and abdominal ultrasonography was performed to measure PFT and SFT.Results: The mean PFT values were 6.1 ± 2.9 mm in patients with PCOS and 4.3 ± 2.3 mm in healthy controls (P = .002). SFT values were also higher in the patient group (9.6 ± 5 mm) compared to healthy subjects (3.5 ± 0.5 mm) (P = .017). A significant positive correlation was found between PFT and BMI (r = 0.368), waist circumference (WC) (r = 0.441), Ferriman-Gallwey (FG) score (r = 0.313), blood pressure (systolic, SBP, r = 0.213; diastolic, DBP, r = 0.215), plasma glucose (r = 0.195), homeostasis model assessment-insulin resistance (HOMA-IR, r = 0.273), SFT (r = 0.555). Conversely, negative correlations were found between PFT and estradiol (r = -0.218) and sex hormone-binding globulin (SHBG, r = -0.304). Nonobese PCOS patients (6.1 ± 3.07 mm) had higher PFT values than nonobese controls (3.47 ± 1.5 mm); however, SFT measurements did not differ (P = .086). In multiple linear regression analysis, SFT (P = .006) was a significant and independent predictor for PFT, along with WC (P = .023). In a stepwise model, SFT was the predictor of PFT (P = .001).Conclusion: PFT values were higher particularly in nonobese PCOS patients compared to nonobese control subjects. There was a significant interaction between PCOS and obesity on PFT.Abbreviations: BMI = body mass index; CT = computed tomography; DBP = diastolic blood pressure; FPG = fasting plasma glucose;; HDL-cholesterol = high-density lipoprotein cholesterol; HOMA-IR = homeostasis model assessment-insulin resistance; hsCRP = high-sensitivity C-reactive protein; LDL-cholesterol = low-density lipoprotein cholesterol; LH = luteinizing hormone; NCAH = nonclassic congenital adrenal hyperplasia; 17-OHP = 17-hydroxyprogesterone; PCOS = polycystic ovary syndrome; PFT = para- and perirenal fat; SAT = subcutaneous abdominal adipose tissue; SBP = systolic blood pressure; SFT = abdominal subcutaneous fat thickness; TG = triglyceride; US = ultrasound; VAT = visceral abdominal adipose tissue; WC = waist circumference     

Supplemental L-arginine improves feed conversion and modulates lipid metabolism in male and female broilers from 29 to 42 days of age

The excessive accumulation of abdominal fat in broilers is an economic waste. Supplemental dietary L-arginine has been shown to reduce lipogenesis in broilers, but studies on this subject are still scarce. Two experiments were conducted in a 5 × 2 factorial design, with five L-arginine concentrations in diets (0, 3, 6, 9 and 12 g/kg) provided to male and female broilers, from 29 to 42 days of age, reared in boxes or cages, with six replicates of 23 broilers per box and six replicates of three broilers per cage, totalling 1560 broilers. Data on performance, carcass and cuts yield, abdominal fat deposition, chemical composition of the breast, lipid profile and liver enzyme activity were evaluated in experiment 1. In experiment 2, the balance and retention of nitrogen, metabolizability coefficients and metabolizable energy of feed were determined and the treatments were evaluated in six replicates of three broilers per cage, totalling 180 broilers. In both experiments, there was no interaction (P > 0.05) between L-arginine concentration in the diet and sex of the broilers for all parameters evaluated. Male broilers showed higher (P < 0.05) weight gain, noble cuts yield, levels of CP and mineral matter in the breast, better feed conversion (P < 0.05) and lower (P < 0.05) malic enzyme activity in the liver and abdominal fat deposition. On the other hand, regardless of sex, the increase in L-arginine concentration in the diet improved (P < 0.05) the feed conversion in addition to reducing (P < 0.05) serum levels of total cholesterol and low-density lipoprotein cholesterol, the malic enzyme activity in the liver and abdominal fat deposition. In conclusion, male broilers had better productive results than females. However, supplementing the diet of male or female broilers from 29 to 42 days of age with L-arginine at a concentration of 6.87 g/kg represents a nutritional strategy to improve feed conversion and reduce circulating triacylglycerol and cholesterol levels, NADPH synthesis by liver malic enzyme and abdominal fat deposition, without negatively affecting the carcass and noble cuts yield, the amount of nitrogen excreted by the broilers and the energy value of the feed.     

Impact of Type 2 Diabetes on Nonalcoholic Steatohepatitis and Advanced Fibrosis in Patients with Nonalcoholic Fatty Liver Disease

Objective: Type 2 diabetes mellitus (T2DM) is a risk factor for nonalcoholic fatty liver disease (NAFLD). The aim of this study was to investigate the effect of T2DM on nonalcoholic steatohepatitis (NASH) and advanced fibrosis.Methods: A total of 221 NAFLD patients who had undergone a liver biopsy were included in this study. Subjects were divided into a non-T2DM group and a T2DM group based on glycemic control. NASH was diagnosed by the joint presence of steatosis, ballooning, and lobular inflammation. The steatosis, activity, and fibrosis (SAF) score and NAFLD activity score (NAS) were used to evaluate the severity of NAFLD. The severity of liver fibrosis was evaluated based on the fibrosis stage.Results: The total percentages of NASH and advanced fibrosis in this study were 95.0% and 50.2%, respectively. The percentages of NASH and advanced fibrosis in NAFLD patients with T2DM were 96.1% and 56.5%, respectively, which were higher than those in the non-T2DM group. SAF score (especially activity and fibrosis stage) and NAS (especially ballooning) were higher in NAFLD patients with T2DM than in NAFLD patients without T2DM. Glycemic control and insulin resistance were positively associated with SAF, NAS, and fibrosis stage. Additionally, T2DM elevated the risk of a high NAS and advanced fibrosis.Conclusion: T2DM increases the risk of serious NASH and advanced fibrosis in patients with NAFLD. Liver biopsy can be performed in NAFLD patients with T2DM to confirm the stage of NAFLD. Screening of NASH and advanced fibrosis in NAFLD patients with T2DM is needed.Abbreviations: ALT = alanine aminotransferase; APO = apolipoprotein; AST = aspartate aminotransferase; BMI = body mass index; CI = confidence interval; FPG = fasting plasma glucose; GGT = gamma-glutamyl transferase; HbA1c = hemoglobin A1c; HDL-c = high-density-lipoprotein cholesterol; ¹H-MRS = proton magnetic resonance spectroscopy; HOMA-IR = homeostasis model assessment of insulin resistance; 2hPG = postprandial plasma glucose at 2 hours; LDL-c = low-density-lipoprotein cholesterol; LFC = liver fat content; NAFLD = nonalcoholic fatty liver disease; NAS = NAFLD activity score; NASH = nonalcoholic steatohepatitis; OGTT = oral glucose tolerance test; OR = odds ratio; T2DM = type 2 diabetes mellitus; TC = total cholesterol; TG = triglyceride; SAF = steatosis, activity, and fibrosis; US-FLI = ultrasonographic fatty liver indicator     

n-3 Fatty acids combined with flavan-3-ols prevent steatosis and liver injury in a murine model of NAFLD

Non-alcoholic fatty liver disease (NAFLD) affects 25% of adults and at present no licensed medication has been approved. Despite its complex patho-physiology, dietary strategies aiming at delaying or preventing NAFLD have taken a reductionist approach, examining the impact of single components. Accumulating evidence suggests that n-3 LC-PUFAs are efficacious in regulating lipogenesis and fatty acid oxidation. In addition, plant derived flavonoids are also emerging as a dietary strategy for NAFLD prevention, with efficacy attributed to their insulin sensitising and indirect antioxidant effects. Based on knowledge of their complementary molecular targets, we aimed to demonstrate that the combination of n-3 LC-PUFA (n-3) and flavan-3-ols (FLAV) prevents NAFLD. In a high-fat high-fructose (HF/HFr) fed C57Bl/6 J mouse model, the independent and interactive impact of n-3 and FLAV on histologically defined NAFLD, insulin sensitivity, weight gain, intestinal and hepatic gene expression, intestinal bile acids were examined. Only the combination of FLAV and n-3 (FLAVn-3) prevented steatosis as evidenced by a strong reduction in hepatocyte ballooning. While FLAV reduced body (? 28–30%), adipose tissue (? 45–50%) weights and serum insulin (? 22–25%) as observed following an intra-peritoneal glucose tolerance test, n-3 downregulated the expression of Srebf1 and the lipogenic genes (Acaca, Fasn). Significant impacts of interventions on intestinal bile acid metabolism, farnesoid X receptor (Fxr) signalling in the intestine and liver, and hepatic expression of fatty acid transporters (Fabp4, Vldlr, Cd36) were also evident. FLAVn-3 may be a novel intervention for NAFLD. Future research should aim to demonstrate its efficacy in the prevention and treatment of human NAFLD.     

Practice Patterns in Screening for Metabolic Disease in Women with PCOS of Diverse Race-Ethnic Backgrounds

ObjectivesWomen with polycystic ovary syndrome (PCOS) are at high risk for metabolic disorders, which prompted the American Association of Clinical Endocrinologists (AACE) to publish a 2005 position statement recommending screening for metabolic disease.The purposes of the present study were to 1) to examine changes in screening rates for obesity, type 2 diabetes (T2D), metabolic syndrome (MetS), hyperlipidemia (HL), nonalcoholic fatty liver disease (NAFLD), and hypertension (HTN) in women with PCOS after publication of the 2005 AACE position statement and 2) to determine if screening rates and metabolic disorders vary by race-ethnicity.MethodsPCOS cases in 2006 (n = 547) and 2011 (n = 1,159) and metabolic disorders were identified by International Classification of Diseases, 9th revision (ICD9) code. Screening rates for metabolic disorders were determined by the presence of blood tests (hemoglobin A1c [HbA_1c], lipid profile, alanine aminotransferase/aspartate aminotransferase [ALT/AST]).ResultsIn 2006, ≤ 25% of PCOS patients underwent recommended screening tests: HbA1c 18%; lipid profile < 20%; ALT/AST ≤ 25%. By 2011, only HbA1c testing had increased (18% to 21%). Obesity increased from 35% to 40%, while other metabolic disorders remained stable. Black women had the highest rates of obesity and HTN in 2011 (Obesity: Black 48%, Hispanic 44%, White 33%, Other 31%, P < .0001; HTN: Black 18%, Hispanic 9%, White 10%, Other 7%, P < .0001). Blacks and Hispanics were screened more often with ALT/AST testing (Black 27/27%, Hispanic 28/27%, White 23/22%, Other 17/18%, P = .02/.03). Screening rates were higher in the endocrine clinic for all metabolic disorders than in other clinics (P < .05).ConclusionDespite the publication of recommendations in 2005, screening rates for metabolic disease in women with PCOS remained low across all race-ethnicities in 2011. (Endocr Pract. 2014;20:855-863)     

High-Dose Glucocorticoid Treatment Does Not Induce Severe Hyperglycemia in Young Patients with Autoimmune Diseases by Cgms

Objective: High-dose glucocorticoids (HDG) are used in the treatment of autoimmune diseases. Glucocorticoids-induced hyperglycemia (GIH) is often described in elderly patients. In young patients with autoimmune diseases, however, the risk for GIH has not been well characterized.Methods: We recruited 24 inpatients (median age, 32 years; interquartile range, 25–42) with exacerbations of autoimmune diseases, receiving 1 to 2 mg/kg/day prednisone or equivalent methylprednisone. Fourteen subjects were naïve to glucocorticoids (group 1) and 10 subjects were on glucocorticoid maintenance (≤15 mg/day prednisone at least 3 months) (group 2) prior to HDG. All subjects were monitored by continuous glucose monitoring system (CGMS) for 3 days.Results: GIH developed in 21 (91%) subjects, 11/13 in group 1 and 10/10 in group 2. The main peak of glucose excursion (128.7 ± 6.4 mg/dL, group 1; 143.9 ± 10.0 mg/dL, group 2) occurred at 2 to 3 pm. Another peak occurred before sleep. Two-hour mean postprandial glucose levels were normal in both groups: breakfast, 105.0 ± 28.4 versus 125.6 ± 24.4 mg/dL, P = .065; lunch, 115.7 ± 21.1 versus 135.9 ± 29.0 mg/dL, P = .082; dinner, 122.8 ± 18.5 versus 137.8 ± 26.4 mg/dL, P = .144 in groups 1 and 2, respectively. There was a positive association between pretreatment hemoglobin A1C and peak glucose levels (P<.0001). Notably, 35% of our subjects experienced early morning hypoglycemia (65.2 ± 2.8 mg/dL).Conclusion: In hospitalized young patients with auto-immune diseases, CGMS data revealed that short-term consistent HDG treatment induced mild hyperglycemia, peaking in the early afternoon and before sleep. Early morning hypoglycemia was found in 35%.Abbreviations: A1C = hemoglobin A1C; AUC = the area under the curve; BG = blood glucose; BMI = body mass index; CGMS = continuous glucose monitoring system; DM = diabetes mellitus; FBG = fasting blood glucose; GA = glycated albumin; GCs = glucocorticoids; GIH = glucocorticoids-induced hyperglycemia; HDG = high-dose glucocorticoids; HOMA-IR = Homeostasis Model Assessment-Insulin Resistance; IG = interstitial glucose; IQR = interquartile range; PUMCH = Peking Union Medical College Hospital; SLE = systemic lupus erythematosus     

Thyroid-stimulating Hormone Levels Are Inversely Associated With Serum Total Bile Acid Levels: a Cross-Sectional Study

Objective: Bile acids (BAs) synthesized from cholesterol play a critical role in eliminating excess cholesterol to maintain cholesterol homeostasis. BAs are also signaling molecules that are involved in the regulation of lipid, glucose, and energy metabolism. Thyroid-stimulating hormone (TSH) has been found to decrease liver BA synthesis via a sterol regulatory element-binding protein 2/hepatocyte nuclear factor 4 alpha/cholesterol 7α-hydroxylase (SREBP-2/HNF-4α/CYP7A1) pathway in vivo and in vitro. However, the relationship between serum TSH and total BA levels in humans is still unclear.Methods: This was a single-center cross-sectional study of 339 subclinical hypothyroidism (SCH) patients and an equal number of controls matched by age and sex from 11,000 subjects.Results: Serum total BA levels significantly decreased (3.11 ± 2.05 vs. 5.87 ± 2.39, P<.01), while total cholesterol (TC) levels increased (5.02 ± 0.65 vs. 4.88 ± 0.63, P<.01) in subclinical hypothyroidism (SCH) patients compared to control subjects. Serum TSH and BA levels were significantly and negatively correlated in subclinical hypothyroid patients who were also hypercholesterolemic (r_s = -0.189, P = .004). Each 1 μIU/mL increase in TSH level was associated with a decrease in log-transformed values of total BAs (logTBAs) by 0.182 after controlling for confounding factors relevant to BA metabolism. The relationship between TSH and serum total BAs was more significant in subjects younger than 65 years.Conclusion: Our results suggested that TSH is correlated with the total BA level in SCH patients independent of thyroid hormone, which suggests a potential physiological role of TSH and the importance of maintaining normal range TSH in SCH patients.Abbreviations:BA = bile acidCYP7A1 = cholesterol 7α-hydroxylaseFBG = fasting blood glucoseHDL-C = highdensity lipoprotein cholesterolLDL-C = low-density lipoprotein cholesterollogTBAs = log-transformed values of total BAsSCH = subclinical hypothyroidismTC = total cholesterolTG = triglycerideTH = thyroid hormoneTSH = thyroid-stimulating hormone     

Arterial Wall Stiffness and the Risk of Atherosclerosis in Egyptian Patients with Overt and Subclinical Hypothyroidism

Objective: Hypothyroidism is associated with an increased risk of atherosclerosis. Pulse wave velocity (PWV) is an index of arterial wall stiffness widely used for noninvasive assessment of early atherosclerosis. We assessed PWV in Egyptian patients with hypothyroidism.Methods: The study included 100 Egyptian females aged 18 to 55 years. They were classified into three groups: group I, 40 women with overt hypothyroidism; group II, 40 women with subclinical hypothyroidism; and group III, 20 euthyroid women as a control group. The three groups were age matched. Doppler ultrasonography was used to calculate the heart-femoral PWV.Results: PWV was significantly higher in women with overt and subclinical hypothyroidism as compared with the control group (9.55 ± 1.81 m/s and 9.30 ± 1.28 m/s, respectively vs. 7.82 ± 2.14 m/s; P<.001 and <.01, respectively). There was a positive correlation between thyroid-stimulating hormone (TSH) and PWV in women with overt hypothyroidism and in those with subclinical hypothyroidism (P<.05 for both). Multivariate regression analysis showed that age and diastolic blood pressure were independent determinants of PWV in women with overt and subclinical hypothyroidism (P<.01 for all). TSH was also an independent determinant of PWV in both groups (P<.05 for both).Conclusion: PWV is significantly higher in Egyptian women with overt and subclinical hypothyroidism as compared with normal control subjects. This denotes early increase in arterial wall stiffness in patients with hypothyroidism, even in the subclinical phase. The positive correlation between PWV and TSH in both groups of patients suggests that the risk of atherosclerosis is proportionate to the severity of hypothyroidism.Abbreviations: ABI = ankle/brachial index; baPWV = brachial-ankle pulse wave velocity; BP = blood pressure; CIMT = carotid intima-media thickness; ECG = electrocardiogram; FT4 = free thyroxine; HDL = high-density lipoprotein; hfPWV = heart-femoral pulse wave velocity; LDL = low-density lipoprotein; PTT = pulse transit time; PWV = pulse wave velocity; SCH = subclinical hypothyroidism; TSH = thyroid-stimulating hormone     

Xanthohumol lowers body weight and fasting plasma glucose in obese male Zucker fa/fa rats

Obesity contributes to increased risk for several chronic diseases including cardiovascular disease and type 2 diabetes. Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus), was tested for efficacy on biomarkers of metabolic syndrome in 4 week old Zucker fa/fa rats, a rodent model of obesity. Rats received daily oral doses of xanthohumol at 0, 1.86, 5.64, and 16.9 mg/kg BW for 6 weeks. All rats were maintained on a high fat (60% kcal) AIN-93G diet for 3 weeks to induce severe obesity followed by a normal AIN-93G (15% kcal fat) diet for the last 3 weeks of the study. Weekly food intake and body weight were recorded. Plasma cholesterol, glucose, insulin, triglyceride, and monocyte chemoattractant protein-1 (MCP-1) levels were assessed using commercial assay kits. Plasma and liver tissue levels of XN and its metabolites were determined by liquid–chromatography tandem mass spectrometry. Plasma and liver tissue levels of xanthohumol were similar between low and medium dose groups and significantly (p < 0.05) elevated in the highest dose group. There was a dose-dependent effect on body weight and plasma glucose levels. The highest dose group (n = 6) had significantly lower plasma glucose levels compared to the control group (n = 6) in male but not female rats. There was also a significant decrease in body weight for male rats in the highest dose group (16.9 mg/kg BW) compared to rats that received no xanthohumol, which was also not seen for female rats. Plasma cholesterol, insulin, triglycerides, and MCP-1 as well as food intake were not affected by treatment. The findings suggest that xanthohumol has beneficial effects on markers of metabolic syndrome.     

Conditioning Factors for High Cardiovascular Risk in Patients with Cushing Syndrome

Objective: To characterize the alterations in carbohydrate and lipoprotein metabolism, to evaluate markers of lipoprotein functionality, and to identify the presence of novel atherogenic risk factors in patients with Cushing syndrome (CS) in comparison with sex- and age-matched controls.Methods: In an open, cross-sectional study, 32 nontreated patients with active CS were consecutively recruited from the Endocrinology Service at “José de San Martín” Clinical Hospital, University of Buenos Aires, Argentina, between April 11, 2010 and December 11, 2012. The patients were compared with sex- and age-matched controls.Results: Versus controls, patients with CS presented with excess weight, central obesity, and hypercortisolism. They also exhibited an insulin-resistant state, with high resistin levels (median [interquartile range], 16 [10 to 22] ng/mL versus 6 [5 to 9] ng/mL; P<.0001), a more atherogenic lipoprotein profile, high oxidized low-density lipoprotein levels (oxLDL; mean ± SD, 100 ± 31 U/L versus 75 ± 32 U/L; P<.05) and high sensitive C-reactive protein levels (median [interquartile range], 1.2 [0.6 to 3.1] mg/L versus 0.6 [0.3 to 1.1] mg/L; P<.05), and increased leukocyte count (mean ± SD, 9.5 ± 2.6 × 10³ cells/μL versus 6.5 ± 1.4 × 10³ cells/μL; P<.0001). Multivariate analyses showed that the increase in waist circumference was associated with both the diagnosis of CS and the degree of insulin resistance. Resistin concentration was related to a greater extent to the diagnosis of CS than to homeostasis model assessment–insulin resistance. Triglyceride and oxLDL levels were only significantly associated with the diagnosis of CS.Conclusion: Hypercortisolism is related to the increase observed in triglycerides and oxLDL levels, and, in combination with insulin resistance, acts to increase waist circumference and amplify the inflammatory process, key factors for the development of cardiovascular disease.Abbreviations: apo = apolipoprotein ARE = arylesterase CETP = cholesteryl ester transfer protein CRP = C-reactive protein CS = Cushing syndrome CV = coefficient of variation HDL = high-density lipoprotein HDL-C = high-density-lipoprotein cholesterol HOMA = homeostasis model assessment LDL = low-density lipoprotein LDL-C = low-density-lipoprotein cholesterol Lp-PLA₂ = lipoprotein-associated phospholipase A₂ oxLDL = oxidized LDL PON = paraoxonase TG = triglyceride     

Meat eating and nutritional quality of lambs sired by high and low muscle density rams

Intramuscular fat (IMF) content affects eating and nutritional quality of lamb meat. Muscle density measured by computer tomography is an in vivo proxy measure of IMF content that affects eating and nutritional quality of lamb meat. Lambs sired by high muscle density (HMD) or low muscle density (LMD) rams, selected for slaughter on commercial criteria were measured for meat quality and nutritional traits. A restricted maximum likelihood model was used to compare lamb traits. Additionally, regression analysis of sire estimated breeding value (EBV) for muscle density was performed for each meat quality trait. Muscle density EBV had a negative regression with IMF content (P < 0.001). For each unit increase in muscle density EBV, there was a significant decrease in loin (− 1.69 mg/100 g fresh weight) and topside IMF (− 0.03 mg/100 g fresh weight). Muscle density EBV had a negative regression with grouped saturated and monounsaturated fatty acids concentration (and monounsaturated proportion P < 0.001). Muscle density EBV had a negative regression with loin sensory traits tenderness, juiciness and overall liking and many novel tenderness sensory traits measured (P < 0.05). Selecting for LMD EBV increased IMF content and favourable meat eating quality traits. In contrast, sire muscle density EBV had a positive regression with loin polyunsaturated:saturated fat ratio and grouped polyunsaturated proportion traits (including total polyunsaturated proportion, total omega-6 (n-6) and total omega-3 (n-3) fatty acids (P < 0.001). This is explained by the fact that as sire muscle density EBV increases, polyunsaturated fatty acid proportion increases and the proportion of saturated and monounsaturated fatty acid content decreases. Muscle density EBV had a positive regression with shear force and the novel toughness sensory traits (P < 0.05). Selection for HMD EBV's increased shear force and toughness traits, which is unfavourable for the consumer. Low muscle density sired meat had higher meat colour traits chroma/saturation (+ 0.64, SD 2.30, P = 0.012), redness (+ 0.52, SD 1.91, P = 0.012) and yellowness (+ 0.31, SD 1.49, P = 0.08) compared to HMD sired meat. Selection for LMD could be used within a breeding programme to increase IMF content and enhance both meat colour and improve eating quality parameters.