Nutrients utilization in obese individuals with and without hypertriglyceridemia

Advances in Phenotyping Obesity and in Its Dietary and Pharmacological Treatment: A Narrative Review

In recent times, it has become evident that there are individuals who, from a metabolic point of view, are affected by obesity but have a normal body mass index. There are also metabolically healthy individuals with a high body mass index who are thus are considered as to be affected by obesity obese. Understanding that individuals with obesity are phenotypically heterogeneous is a relatively novel concept which, although present in the scientific literature, unfortunately has not yet had an impact in clinical practice. However, common dietary approaches are not effective in treating large numbers of obese patients with obesity. This narrative review, based on the material searched via PubMed and the Web of Science up to October 2021, proposes a downsizing of the role of the body mass index in identifying the individual with “true obesity” since it is only partially useful, and suggests a new approach which also integrates the body composition and assessment of metabolic parameters. This approach leads to personalized therapies that work best for each obesity phenotype in reducing the risk of non-communicable diseases.

Effect of Dietary Strategies on Respiratory Quotient and Its Association with Clinical Parameters and Organ Fat Loss: A Randomized Controlled Trial

The relation between changes in respiratory quotient (RQ) following dietary interventions and clinical parameters and body fat pools remains unknown. In this randomized controlled trial, participants with moderate abdominal obesity or/and dyslipidemia (n = 159) were randomly assigned to a Mediterranean/low carbohydrate (MED/LC, n = 80) or a low fat (LF, n = 79) isocaloric weight loss diet and completed a metabolic assessment. Changes in RQ (measured by indirect calorimeter), adipose-tissue pools (MRI), and clinical measurements were assessed at baseline and after 6 months of intervention. An elevated RQ at baseline was significantly associated with increased visceral adipose tissue, hepatic fat, higher levels of insulin and homeostatic insulin resistance. After 6 months, body weight had decreased similarly between the diet groups (−6 ± 6 kg). However, the MED/LC diet, which greatly improved metabolic health, decreased RQ significantly more than the LF diet (−0.022 ± 0.007 vs. −0.002 ± 0.008, p = 0.005). Total cholesterol and diastolic blood pressure were independently associated with RQ changes (p = 0.045). RQ was positively associated with increased superficial subcutaneous-adipose-tissue but decreased renal sinus, pancreatic, and intramuscular fats after adjusting for confounders. Fasting RQ may reflect differences in metabolic characteristics between subjects affecting their potential individual response to the diet.

PPAR-Alpha Agonist Fenofibrate Combined with Octreotide Acetate in the Treatment of Acute Hyperlipidemia Pancreatitis

At present, there are more and more patients with acute hypertriglyceridemia pancreatitis in clinical practice. Common treatment measures include fasting and water withdrawal, fluid resuscitation, and somatostatin. In recent years, studies have pointed out that the PPARa agonist fenofibrate may help improve the condition of such patients. Therefore, through clinical research and analysis, we reported for the first time that fenofibrate combined with octreotide acetate has a more excellent effect in the treatment of patients with acute hypertriglyceridemia pancreatitis, and from the perspective of signal pathways, we revealed that the combination of the two drugs has an effect on NF-κB P65. The synergistic inhibitory effect proves that the combined treatment is beneficial to control inflammation, protect liver function, and improve the prognosis of patients. It is worthy of clinical promotion.

Association of basal metabolic rate and fuel oxidation in basal conditions and during exercise, with plasma S-klotho: the FIT-AGEING study

S-klotho, the shed form of α-klotho, is thought to be an ageing suppressor with functions related to the physiology of energy metabolism. However, it remains unknown whether ageing biomarkers such as S-klotho and/or chronological ageing are associated in any way with basal metabolic rate (BMR) and fuel oxidation in basal conditions and during exercise. The present work investigates the association of BMR and fuel oxidation in basal conditions and during exercise, with plasma S-klotho in middle-aged, sedentary adults. BMR was measured by indirect calorimetry in 74 such subjects (53% women; age 53.7±5.1 years) following standard procedures, and their fuel oxidation estimated via stoichiometric equations. The maximal fat oxidation during exercise (MFO) and the intensity of exercise that elicits MFO (Fat_max) were determined using a walking graded exercise test. No relationship was seen between BMR and plasma S-klotho (P>0.1), although both basal fat oxidation and MFO showed positive associations with this protein (both P<0.001); these relationships persisted after controlling for age, sex and fat mass. However, no significant associations were seen between BMR, basal fat oxidation or MFO and chronological age (all P>0.1). The present findings suggest that basal fat oxidation and MFO are strongly associated with plasma S-klotho in middle-aged sedentary adults. These results support the idea that metabolic flexibility is a powerful predictor of biological ageing.

Individuals with Metabolically Healthy Overweight/Obesity Have Higher Fat Utilization than Metabolically Unhealthy Individuals

The mechanisms underlying the change in phenotype from metabolically healthy to metabolically unhealthy obesity are still unclear. The aim of this study is to investigate whether a difference in fasting fat utilization exists between overweight/obese individuals with a favorable cardiovascular risk profile and those with Metabolic Syndrome and Type 2 diabetes. Furthermore, we sought to explore whether there is an association between fasting fat utilization and insulin resistance. In this cross-sectional study, 172 overweight/obese individuals underwent a nutritional assessment. Those with fasting glucose ≥ 126 mg/dL or antidiabetic treatment were considered to be diabetics. If at least three of the NCEP criteria were present, they had Metabolic Syndrome, while those with less criteria were considered to be healthy overweight/obese. An indirect calorimetry was performed to estimate Respiratory Quotient, an index of nutrient utilization. A lower Respiratory Quotient (i.e., higher fat utilization) was found in healthy overweight/obese individuals than in those with Metabolic Syndrome and Type 2 diabetes (0.85 ± 0.05; 0.87 ± 0.06; 0.88 ± 0.05 respectively, p = 0.04). The univariate and multivariable analysis showed a positive association between the Respiratory Quotient and HOMA-IR (slope in statistic (B) = 0.004; β = 0.42; p = 0.005; 95% Confidence interval = 0.001-0.006). In this study, we find, for the first time, that the fasting Respiratory Quotient is significantly lower (fat utilization is higher) in individuals who are metabolically healthy overweight/obese than in those with metabolically unhealthy obesity. In addition, we demonstrated the association between fat utilization and HOMA-IR, an insulin resistance index.

Age-related changes in basal substrate oxidation and visceral adiposity and their association with metabolic syndrome

PURPOSE

Ageing is directly associated with visceral fat (VAT) deposition and decline of metabolically active cellular mass, which may determine age-related shifts in substrate oxidation and increased cardiometabolic risk. We tested whether VAT and fasting respiratory quotient (RQ, an index of macronutrient oxidation) changed with age and if they were associated with increased risk of metabolic syndrome (MetSyn).

METHODS

A total of 2819 adult participants (age range: 18-81 years; men/women: 894/1925) were included; we collected history, anthropometric measures, biochemistry, smoking habits, and physical activity. The body mass index range was 18.5-60.2 kg/m(2). Gas exchanges (VO2 and VCO2) were measured by indirect calorimetry in fasting conditions, and RQ was calculated. Body composition was measured by bioelectrical impedance. Abdominal subcutaneous fat and VAT were measured by ultrasonography. MetSyn was diagnosed using harmonised international criteria. Multivariate linear and logistic regression models were utilised.

RESULTS

VAT increased with age in both men (r = 0.31, p < 0.001) and women (r = 0.37, p < 0.001). Basal RQ was not significantly associated with age (p = 0.49) and VAT (p = 0.20); in addition, basal RQ was not a significant predictor of MetSyn (OR 3.31, 0.57-19.08, p = 0.27). VAT was the primary predictor of MetSyn risk in a fully adjusted logistic model (OR 4.25, 3.01-5.99, p < 0.001).

CONCLUSIONS

Visceral adiposity remains one of the most important risk factors for cardiometabolic risk and is a significant predictor of MetSyn. Post-absorptive substrate oxidation does not appear to play a significant role in age-related changes in body composition and cardiometabolic risk, except for a correlation with triglyceride concentration.

Association between low C-peptide and low lumbar bone mineral density in postmenopausal women without diabetes

In this population-based, cross-sectional study in Italian postmenopausal females not affected by diabetes, we showed a link between serum C-peptide and lumbar bone mineral density, suggesting that C-peptide exerts an insulin-independent effect on bone mass.

INTRODUCTION

It is well known that type 1 (T1) diabetes, characterized by insulin and C-peptide deficiency, is associated with a low lumbar bone mineral density and an increased risk for fracture. While a role for insulin in the pathogenesis of osteoporosis has been demonstrated, the association between C-peptide and the bone mineral density has not been investigated. We conducted a study in a cohort of 84 postmenopausal women without diabetes to clarify the association between serum C-peptide and the lumbar bone mineral density.

METHODS

Participants underwent a bone mineral density evaluation by DXA and biochemical analysis including the C-peptide assay.

RESULTS

rteen percent of the population had osteoporosis and 38% had osteopenia. With ANOVA test, we showed that women with the lowest C-peptide concentration had lower lumbar mineral density in comparison to those in all other C-peptide concentration group (p = 0.02 among groups after adjustment). The univariate and multivariate analysis showed that C-peptide was positively associated with both lumbar T-score and Z-score besides other well-known factors like age (with T-score p < 0.001; beta = -0.38) and BMI (with T-score p = 0.009; beta = 0.34), while insulin was not correlated with the lumbar bone mineral density. The area under the receiver operating characteristic (ROC) curve for C-peptide to predict the absence of lumbar osteoporosis was 0.74 (SE = 0.073; p = 0.013).

CONCLUSIONS

These results suggest that C-peptide may exert an insulin- and BMI-independent effect on lumbar bone mineral density and that further large-scale studies are needed in order to clarify its role in bone mineralization especially in subjects without diabetes.