Role of interleukin-1beta in the development of malnutrition in chronic renal failure patients

Fibroblast Growth Factor 23 and Muscle Wasting: A Metabolic Point of View

Protein energy wasting (PEW), mostly characterized by decreased body stores of protein and energy sources, particularly in the skeletal muscle compartment, is highly prevalent in patients with moderate to advanced chronic kidney disease (CKD). Fibroblast growth factor 23 (FGF23) is an endocrine hormone secreted from bone and has systemic actions on skeletal muscle. In CKD, FGF23 is elevated and its coreceptor α-klotho is suppressed. Multiple lines of evidence suggest that FGF23 is interconnected with various mechanisms of skeletal muscle wasting in CKD, including systemic and local inflammation, exaggerated oxidative stress, insulin resistance (IR), and abnormalities in adipocytokine metabolism. Investigation of metabolic actions of FGF23 on muscle tissue could provide new insights into metabolic and nutritional abnormalities observed in patients with CKD.

Nutritional status and metabolic profile in neurologically impaired pediatric surgical patients

BACKGROUND

Malnutrition is reported in pediatric neuromotor disability and impacts the child's health. We described the nutritional and metabolic status in neurologically impaired (NI) children undergoing surgery.

METHODS

Anthropometry, body composition, hormonal and nutritional evaluations were performed in 44 NI subjects (13.7±8.0 years). Energy needs were calculated by Krick's formula. Metabolic syndrome (MS) was defined applying the following criteria (≥3 defined MS): fasting blood glucose >100 mg/dL and/or homeostasis model assessment for insulin resistance (HOMA-IR) >97.5th percentile, trygliceride level >95th percentile, high-density lipoprotein (HDL)-cholesterol level <5th percentile, systolic/diastolic pressure >95th percentile; whilebody mass index - standard deviation score (BMI-SDS) <2 and biochemical malnutrition markers (≥2) defined undernutrition.

RESULTS

Energy intake was not adequate in 73.8% of the patients; no correlation between energy intake and BMI was noted. Undernutrition was noted in 34.1% of patients and MS in 11.36% of subjects. Fifty percent of the patients presented with insulin resistance, which was not related to BMI, body composition or other MS components.

CONCLUSIONS

Nutritional and metabolic monitoring of disabled children and young adults is recommended to prevent adverse outcomes associated with malnutrition.

IL-6 572 C/G, 190 C/T, and 174 G/C gene polymorphisms in children's malnutrition

OBJECTIVES

The aim of the present study was to establish the correlations between the polymorphisms of the genes interleukin-6 (IL-6) 572, 190, and 174 in children's malnutrition.

METHODS

We assessed 283 hospitalized children and divided them into 2 groups: group I (control) included 110 patients with normal nutritional status, median (range) age 10.90 (1-18) years; and group II consisted of 173 malnourished patients, median (range) age 10.70 (1-18) years.

RESULTS

The 2 groups underwent IL-6 572 cytosine allele (C)/guanine allele (G), 190 C/thymine allele (T), and 174 G/C polymorphism testing, measurement of anthropometric indicators (mid-upper arm circumference and tricipital skinfold thickness [TST]), and paraclinical evaluation (protein, albumin). We observed that the GG and CG genotypes were more frequent in malnourished children for the IL-6 174 gene (P = 0.0001), whereas the CT heterozygous genotype was more frequent in the malnourished group for the IL-6 190 gene (P = 0.003). Body mass index (BMI), middle upper arm circumference (MUAC), TST, and low serum albumin levels correlated with the GG and CG genotypes of the IL-6 572 and IL-6 174 genes, and with the CT genotype of the IL-6 190 gene, in children with malnutrition, whereas the IL-6 190 TT genotype was a protective factor for malnutrition (P = 0.0001).

CONCLUSIONS

Malnutrition is more frequently associated in children with IL-6 174 G allele carriers (GG and CG genotypes), whereas IL-6 190 TT genotype has a protective function. In malnourished children, the IL-6 572/190/174 GG/CT/CG, GG/CT/GG, GG/CC/GG, and GG/CC/CG combined genotypes are more frequent.

The peptidic middle molecules: is molecular weight doing the trick?

Chronic kidney disease (CKD) is characterized by a gradual endogenous intoxication caused by the progressive accumulation of bioactive compounds that in normal conditions would be excreted and/or metabolized by the kidney. Uremic toxicity now is understood as one of the potential causes for the excess of cardiovascular disease and mortality observed in CKD. An important family of uremic toxins is that of the peptidic middle molecules, with a molecular weight ranging between 500 and 60,000 Da, which makes them, as a consequence, difficult to remove in the process of dialysis unless the dialyzer pore size is large enough. This review provides an overview of the main and best-characterized peptidic middle molecules and their role as potential culprits of the cardiometabolic complications inherent to CKD patients.

Ghrelin treatment of chronic kidney disease: improvements in lean body mass and cytokine profile

Chronic kidney disease (CKD) is associated with an increase in inflammatory cytokines and can result in cachexia with loss of muscle and fat stores. We previously demonstrated the efficacy of treating a model of cancer cachexia with ghrelin and a ghrelin receptor agonist. Currently, we examine a surgical model of CKD in rats, resulting in uremia and decreased accrual of lean body mass. Treatment with ghrelin and two ghrelin receptor agonists (BIM-28125 and BIM-28131) resulted in increased food intake and an improvement in lean body mass accrual that was related in part to a decrease in muscle protein degradation as assessed by muscle levels of the 14-kDa actin fragment resulting from cleaved actomyosin. Additionally, there was a decrease in circulating inflammatory cytokines in nephrectomized animals treated with ghrelin relative to saline treatment. Ghrelin-treated animals also had a decrease in the expression of IL-1 receptor in the brainstem and a decrease in expression of prohormone convertase-2, an enzyme involved in the processing of proopiomelanocortin to the anorexigenic peptide alpha-MSH. We conclude that ghrelin treatment in uremia results in improved lean mass accrual in part due to suppressed muscle proteolysis and possibly related to antiinflammatory effects.