Agnieszka Żak-Gołąb

The Influence of Weight Loss on Serum Osteoprotegerin Concentration in Obese Perimenopausal Women

Objective: To assess the influence of weight reduction therapy on serum osteoprotegerin (OPG) concentration in obese patients and compare these results with normal‐weight controls.

Gut microbiota, microinflammation, metabolic profile, and zonulin concentration in obese and normal weight subjects.

The association between gut microbiota and circulating zonulin level, a marker of intestinal permeability, has not been studied yet. The aim of the study is the assessment of plasma zonulin, haptoglobin and proinflammatory cytokines (TNF-α and IL-6) levels in relation to composition of gut microbiota in obese and normal weight subjects. Circulating inflammation markers, such as TNF-α, sTNFR1, sTNFR2, IL-6, zonulin, and haptoglobin levels were measured and semiquantitative analysis of gut microbiota composition was carried out in 50 obese and 30 normal weight subjects without concomitant diseases. Higher circulating zonulin, TNF-α, sTNFR1, sTNFR2, and IL-6 levels were found in the obese subjects. Plasma zonulin level correlated positively with age (r = 0.43, P < 0.001), body mass (r = 0.30, P < 0.01), BMI (r = 0.33, P < 0.01), fat mass and fat percentage (r = 0.31, P < 0.01 and r = 0.23, P < 0.05, resp.). Positive correlations between bacterial colony count and sTNFR1 (r = 0.33, P < 0.01) and plasma zonulin (r = 0.26, P < 0.05) but not haptoglobin levels were found. Additionally, plasma zonulin level was proportional to daily energy intake (r = 0.27, P < 0.05) and serum glucose concentration (r = 0.18, P < 0.05) and inversely proportional to diet protein percentage (r = −0.23, P < 0.05). Gut microbiota-related systemic microinflammation in the obese is reflected by circulating zonulin level, a potential marker of interstitial permeability.

The indexes of arterial structure and function in women with simple obesity: a preliminary study

Obesity is associated with an increased risk of cardiovascular disorders. The aim of the present study was to compare the indexes of arterial structure and function in women with simple obesity and healthy individuals. Twenty-two women with simple obesity (body mass index [BMI]: 33.6 ± 2.9 kg/m2, age: 29.7 ± 6.2 years), and 34 healthy women were included in the study. Healthy subjects were divided into two subgroups according to their age (<35 and >45 years): Control A-16 young women (age <35 years, BMI: 24.0 ± 3.0 kg/m2), and Control B-18 older women (age >45 years, BMI: 25.8 ± 2.9 kg/m2). Noninvasive, high-resolution, vascular ultrasound was used to evaluate the endothelial-dependent vasodilatation: flow-mediated dilatation of brachial artery (FMD); the arterial structure: intima-media thickness (IMT) of common carotid artery (CCA); and the compliance parameters corresponding to structural changes in large arteries (PWV: pulse wave velocity; PP: pulse pressure; TAC: total arterial compliance; Ao C: aorta compliance, CCA C: CCA compliance, stiffness indexes). Endothelial-dependent vasodilatation as represented by FMD was comparable in the obese group (16.8% ± 7.9%; median: 15.5%) and healthy subjects (Control A: 14.1% ± 4.7%; median: 13.6%; Control B: 13.9% ± 6.5%; median: 13.0%). The mean value of IMT was significantly increased (P < 0.05) in Control B group (0.67 ± 0.07 mm) in comparison to both obese patients (0.58 ± 0.09 mm) and Control A group (0.53 ± 0.05 mm). The compliance parameters (PWV, AoC, CCA C, stiffness indexes) were impaired in obese patients and Control B patients as compared to Control A individuals. PWV and stiffness indexes were significantly increased, and the AoC, CCA C-diameter, CCA C-area were significantly decreased. Simple obesity constitutes an important risk factor accelerating arterial stiffness in women.

Influence of Calcium and Vitamin D Supplementation on Weight and Fat Loss in Obese Women

Background: Dairy products not only reduce the risk of hypertension and cardiovascular diseases but may play a role in the treatment of obesity. As there is some evidence that calcium (Ca) and vitamin D may play a role in effective weight management, we decided to evaluate the influence of Ca and vitamin D supplementation on weight and fat loss in obese women. Material and Methods: Forty obese women were enrolled in this study. Subjects were divided into 2 groups comparable with body mass index (BMI) and age. Group 1 was provided with calcium carbonate and 1-(OH)-vitamin D supplementation. Group 2 was provided with only a diet. Subjects participated in a 3-month weight reduction therapy (balanced diet, modification of life style, and regular physical exercise). Blood samples (serum concentration of Ca, phosphorus (P), parathormone (PTH), 25-(OH)-D3) and clinical characteristics (weight, height, BMI, body composition) were taken at baseline and after the 3-month program. Results: No significant differences of body weight, body fat content, serum parathormone, 25-(OH)-D3 concentration, and plasma total Ca and P concentration were observed between analyzed groups both before and after the treatment. Additionally, we did not observe any significant influence of Ca and vitamin D supplementation on weight and fat loss. Conclusion: Ca plus vitamin D supplementation during a 3-month low caloric diet has no additional effect on weight and fat loss in obese women.

The role of gut microbiota in the pathogenesis of obesity

Obesity is a disease that develops as a result of long-term positive energy balance. In recent years, the influence of gut microflora composition, as a potential factor affecting the energy balance and contributing to fat accumulation, has been studied. It seems that bacteria can affect host energy balance through several mechanisms, such as increased fermentation of undigested polysaccharides and obtaining extra energy from the portion of food, reduced expression of FIAF (fasting-induced adipocyte factor) in the enterocytes with inhibitory activity towards intestinal lipoprotein lipase, and the increased release of peptide YY that slows the intestinal motility. It is also believed that changes in the composition of gut microflora may be one of the factors that induce systemic microinflammation in the obese, an important link in the pathogenesis of obesity related complications, including dyslipidaemia, hypertension and type 2 diabetes. However, the results of previous studies are inconclusive. Many of them have been carried out in an animal model and were not confirmed in studies involving humans. These discrepancies may be due to different composition of the diet, distinct physiological gut microflora and the methodology used in these studies. The present article reviews the current literature on the potential role of gut microflora in the pathogenesis of obesity.

Long-term effects of lipase inhibition by orlistat on gastric emptying and orocecal transit time of a solid meal

BackgroundWe assessed the impact of a prolonged lipase inhibition upon gastric emptying (GE) and orocecal transit time (OCTT) of a 355-kcal low-fat solid meal.MethodsIn double-blind manner, 40 obese women BMI > 30 kg/m2, randomly allocated into two equal groups, took orally t.i.d. 120 mg orlistat or placebo during 8 weeks of a weight-reducing management. At randomization and after 2 months, GE was measured simultaneously with OCTT by means of a 13C-octanoic acid and a hydrogen breath test, respectively. Lipolytic activity was evaluated with a 13C-mixed triglyceride breath test (13C-MTGBT).ResultsA profound lipase inhibition by orlistat was confirmed by a 79.5% ± 16.9% reduction of the cumulative 6-h 13C recovery with 13CMTGBT. GE remained unchanged either in the orlistat (T1/2, 188 ± 35 min start versus 198 ± 36 min end) or the placebo (T1/2, 191 ± 35 min start versus 180 ± 39 min end) group. OCTT increased from 208 ± 54 min to 271 ± 64 min (P < 0.01) after orlistat treatment and did not change significantly (216 ± 76 vs. 234 ± 72 min) in the placebo group.ConclusionsNo adverse effect on the GE and a moderate prolongation of the OCTT of a low-fat solid meal is to be expected under a prolonged treatment with orlistat at a typical dosage regimen.

The influence of oral water load on energy expenditure and sympatho-vagal balance in obese and normal weight women.

Introduction Oral water load may increase the energy expenditure (EE) by stimulation of sympathetic dependent thermogenesis. Thus, drinking of water may be helpful in weight reduction. The aim of the study is to assess the influence of water load on energy expenditure and sympathetic activity in obese and normal weight women. Material and methods Forty-five women were included. Energy expenditure was measured twice, in the morning and after oral water load, by the indirect calorimetric method. The heart rate variability parameters low frequency (LF), high frequency (HF), LF/HF index, standard deviation of normal RR intervals (SDNN) and root mean square difference among successive RR normal intervals (rMSSD) were used for the indirect assessment of the sympatho-vagal balance. Results Resting energy expenditure (REE) was significantly higher in obese than in normal weight women (1529 ±396 kcal/day vs. 1198 ±373 kcal/day; p = 0.02). In both study groups after water load EE increased significantly (by 20% and by 12%, corresponding to 8.6 kcal/h and 5.2 kcal/h respectively), while, LF/HF index increased simultaneously. The increase of energy expenditure (EE) did not exceed the energetic cost of water heating, from room to body temperature – 15 kcal/1000 ml. There was no correlation between changes of energy expenditure (EE) and heart rate variability (HRV) parameters. Conclusions The increase of EE induced by water load is mostly related to the heating of the consumed water to body temperature. The assessment of autonomic balance by means of standard HRV indices had been found insufficient for detection of actually operating mechanisms.

Daily intake and serum concentration of menaquinone-4 (MK-4) in haemodialysis patients with chronic kidney disease.

OBJECTIVES Decreased concentration of menaquinone-4 (MK-4) seems to be an important risk factor of vascular calcification in haemodialysis (HD) patients. Optimal dietary intake, as well as serum MK-4 reference range, in HD has not been determined, yet. The aim of the present study was to assess daily vitamin K1 and MK-4 intakes and their relation to serum MK-4 concentration in HD patients. DESIGN AND METHODS Daily vitamin K1 and MK-4, micro- and macronutrients and energy intakes were assessed using 3-day food diary completed by patients and serum MK-4 concentration was measured by HPLC [limit of quantification (LOQ): 0.055 ng/mL] in 85 HD patients (51 males) and 22 apparently healthy subjects. RESULTS Daily MK-4 intake was significantly lower (by 29%) among HD, while K1 consumption was similar in both groups. Daily MK-4 intake was associated with fat and protein consumption in HD (r=0.43, p<0.001 and r=0.33, p=0.004, respectively). In HD serum MK-4 concentration was more frequently below LOQ (in 41% HD and 5% controls, p<0.001) and in those HD with quantifiable values was lower than in the controls (by 42%). The correlations between MK-4 concentrations and both MK-4 and K1 daily intakes were weaker in HD (r=0.38 and r=0.30 respectively) than in the control group (r=0.47 and r=0.45, respectively). In multiple regression analysis the variability of serum MK-4 concentrations in HD patients was explained by its daily intake. CONCLUSIONS Decreased serum MK-4 concentration in HD patients is caused by lower dietary MK-4 intake, mainly due to diminished meat consumption, and in addition, probably reduced K1 conversion.