Impact of weight loss on inflammation and red blood cell biomarkers after laparoscopic gastric banding surgery

The role of iron metabolism in chronic diseases related to obesity

Obesity is one of the major public health problems threatening the world, as well as a potential risk factor for chronic metabolic diseases. There is growing evidence that iron metabolism is altered in obese people, however, the highly refined regulation of iron metabolism in obesity and obesity-related complications is still being investigated. Iron accumulation can affect the body’s sensitivity to insulin, Type 2 diabetes, liver disease and cardiovascular disease. This review summarized the changes and potential mechanisms of iron metabolism in several chronic diseases related to obesity, providing new clues for future research.

JTZ-951 (enarodustat), a hypoxia-inducible factor prolyl hydroxylase inhibitor, improves iron utilization and anemia of inflammation: Comparative study against recombinant erythropoietin in rat

Anemia with inflammation-induced defective iron utilization is a pathological condition observed in patients suffering from chronic kidney disease (CKD) or chronic inflammatory disease. There is no reasonable treatment for these conditions, because the effects of erythropoiesis stimulating agents (ESAs) or iron supplementation in the treatment of anemia are insufficient. JTZ-951 (enarodustat) has been characterized as a novel, orally bioavailable inhibitor of hypoxia-inducible factor prolyl hydroxylase (HIF-PH), and has been developed as a novel therapeutic agent for anemia with CKD. In this study, the effects of JTZ-951 on iron utilization during erythropoiesis and on anemia of inflammation were compared with those of recombinant human erythropoietin (rHuEPO) using normal rat and rat model of anemia of inflammation. In normal rats, under conditions in which JTZ-951 and rHuEPO showed similar erythropoietic effect, repeated doses of JTZ-951 induced erythropoiesis while retaining the hemoglobin content in red blood cells, while administration of rHuEPO resulted in decrease in some erythrocyte-related parameters. As for iron-related parameters during erythropoiesis, JTZ-951 exhibited more efficient iron utilization compared to rHuEPO. A single dose of JTZ-951 resulted in decrease in hepcidin expression observed within 24 h after administration, but a single dose of rHuEPO did not. In a rat model of anemia of inflammation (also known as a model with functional iron-deficiency), JTZ-951 showed erythropoietic effect, in contrast with rHuEPO. These results suggest that, unlike rHuEPO, JTZ-951 stimulates erythropoiesis by increasing iron utilization, and improves anemia of inflammation.

Impact of Intragastric Balloon Treatment on Adipokines, Cytokines, and Metabolic Profile in Obese Individuals

BACKGROUND

Obesity is accompanied by adipose tissue remodeling characterized by increased production of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, leptin and resistin and reduced secretion of adiponectin, which favors inflammation, metabolic disorders, and cardiovascular diseases. Although intragastric balloon (IGB) can be considered safe and effective for weight loss, its effect on serum levels of these biomarkers has been evaluated only in a few studies, while no previous study evaluated its effect on circulating levels of resistin, TNF-α, and IL-6. The aim of this study was to evaluate the changes in serum levels of metabolic and inflammatory biomarkers in obese patients submitted to IGB treatment.

METHODS

A prospective observational study involving 42 patients with obesity using IGB for 6 months. The patients were evaluated, on the day of insertion and withdrawal or adjustment of IGB, for the following: anthropometric measures and serum levels of adiponectin, leptin, resistin, TNF-α, IL-6, high-sensitivity C-reactive protein (hs-CRP), glucose, insulin, uric acid, triglycerides, and total cholesterol and fractions.

RESULTS

The body mass index decreased from 35.15 ± 0.41 to 29.50 ± 0.54 kg/m². There was a reduction (p < 0.05) in leptin, hs-CRP, glucose, insulin, HOMA-IR, and triglycerides, while the adiponectin/leptin ratio increased (p < 0.05). Moreover, weight loss presented (1) a positive association with the decrease in leptin, hs-CRP, glucose, insulin, HOMA-IR, uric acid, and total cholesterol and (2) a negative association with the reduction in adiponectin/leptin ratio.

CONCLUSIONS

The present study suggests that 6 months of IGB treatment in obese individuals reduce serum leptin and hs-CRP and improves insulin resistance and lipid profile which may decrease cardiovascular risk.

Splenectomy fails to attenuate immuno-hematologic changes after rodent vertical sleeve gastrectomy

Bariatric surgery is on the rise for long-term weight loss and produces various positive metabolic health benefits. The mechanisms that produce surgical weight loss are not yet fully understood. Previous studies showed vertical sleeve gastrectomy prior to gestation resulted in reduced peripheral blood lymphocytes measured during pregnancy due to an undetermined etiology. Further, elevated splenic weight has been associated with vertical sleeve gastrectomy surgery. We hypothesized that perhaps altered splenic filtration was trapping circulating lymphocytes and thus reducing peripheral blood lymphocytes in circulation and contributing to increased spleen weight. We posited whether removal of the spleen concomitant with the stomach surgery may result in an improved immune phenotype. We evaluated female long Evans rats having received Sham surgery or vertical sleeve gastrectomy, with or without splenectomy to determine the contribution of the spleen on metabolic and immune factors after vertical sleeve gastrectomy. Vertical sleeve gastrectomy animals lost significant amounts of body mass and fat mass and ate less in comparison to Sham females during the first five post-operative weeks, but there was no specific effect of the loss of spleen on body mass, fat mass, or food intake. During the post-operative week 6, animals were euthanized and blood recovered for cell sorting of immune cells. There was a reduction in CD3+ total T cells, CD3/CD4+ helper T cells, and CD3/CD8+ cytotoxic T cells, main effect of both bariatric surgery (P  < 0.0001) and splenectomy (P  < 0.01). Furthermore, there was a significant increase in CD45RA+ B cells as a result of splenectomy (P  < 0.001), but a significant reduction in B cells as a result of VSG surgery (P  < 0.05). The changes in total T cells but not B cells were strongly correlated with fat mass. Further studies are needed to understand the cause of the immune changes after surgical weight loss.

Metabolic surgery and iron homeostasis

Iron deficiency and anaemia after metabolic surgery, potentially modifiable nutritional complications, are becoming an increasing cause for concern as prevalence increases with time and there is limited evidence supporting the effectiveness of the current guidelines for prophylactic oral iron supplementation and treatment for deficiency. Abnormalities in iron nutrition predisposing to deficiency are common in severely obese patients, and the low-grade systemic inflammation, also common to these patients, reduces the effectiveness of oral iron supplementation. The surgical procedures result in alterations of foregut anatomy and physiology, which limit iron absorptive capacity and daily food intake. These alterations and the limited effects of oral iron supplementation explain the high prevalence of postoperative iron deficiency and anaemia. This review outlines current mechanisms concerning the pathogenesis of disordered iron nutrition in patients with severe obesity, current gaps in knowledge, and opportunities for quality improvement.

Weight loss achieved by bariatric surgery modifies high-density lipoprotein subfractions and low-density lipoprotein oxidation towards atheroprotection

OBJECTIVES

Weight loss achieved by laparoscopic adjustable gastric banding (LAGB) induces an increase in high-density lipoprotein cholesterol (HDLc) but a small effect on low-density lipoprotein (LDL), although changes in their quality (size and composition) are uncertain. Our aim was to study the impact of weight loss, achieved 13-months after LAGB, on inflammation and dyslipidemia, focusing on HDL and LDL subfractions, and oxidized LDL (oxLDL).

DESIGN & METHODS

We evaluated standard lipid profile, HDL and LDL subfractions, oxLDL, interleukin (IL)-6 and C-reactive protein (CRP), in twenty obese patients, before (T0) and 13-months after LAGB (T1), and in seventeen healthy controls.

RESULTS

At T1, patients showed lower body weight (12% median weight loss) and anthropometric indices; reduction in TG, atherogenic indices, oxLDL, oxLDL/LDL ratio, CRP and IL-6, and enhancement in HDLc; an increase in large HDL and intermediate HDL subfractions, and a decrease in small HDL subfraction; LDL subfractions were not modified. Percentual change (%Δ) of oxLDL, from T0 to T1, correlated significantly and positively with %Δ of small HDL subfraction and with %Δ of body mass index.

CONCLUSIONS

Weight loss induced atheroprotective changes on inflammation, and lipid profile, enhancing larger HDL, the more atheroprotective subfraction, reducing the less protective subclass, small HDL, and reducing oxLDL and oxLDL/LDL ratio. Quality of lipoproteins appears useful cardiovascular risk biomarkers, deserving further studies.

Successful treatment of obesity and insulin resistance via ketogenic diet status post Roux-en-Y

This is a single case of a 65-year-old American woman who presented with substantial weight gain and insulin resistance (IR) post-Roux-en-Y gastric bypass (RYGB) surgery. Before RYGB, she had reached 340 lbs (155 kg) and a body mass index (BMI) of 56.6 kg/m2 The surgery resulted in a 70 lbs (32 kg) weight loss, bringing her BMI, per cent total weight loss (%TWL) and per cent excess weight loss (%EWL) to 44.9 kg/m2, 20.6% and 36.8%, respectively. Unfortunately, her BMI would return to 53.6 kg/m2, nearly her pre-RYGB BMI. It was then she sought the guidance of a primary care physician with expertise in nutrition and medical management of obesity, who placed her on a ketogenic diet. One year later, she had lost 102 lbs (46.4 kg), resulting in a BMI, %TWL and %EWL of 36.6 kg/m2, 31.7%, and 63.1%, respectively, also further resulting in significant improvements of her inflammatory biomarkers. This case presentation will explore current literature, covering the effects of obesity on IR, pre-diabetes and other disease-provoking inflammatory biomarkers.