Roles of chronic low-grade inflammation in the development of ectopic fat deposition. Mediators Inflamm. 2014;2014:418185. [PMID: 25143667 PMCID: PMC4131072 DOI: 10.1155/2014/418185]

Muscle aging and sarcopenia: The pathology, etiology, and most promising therapeutic targets

Sarcopenia is a progressive muscle wasting disorder that severely impacts the quality of life of elderly individuals. Although the natural aging process primarily causes sarcopenia, it can develop in response to other conditions. Because muscle function is influenced by numerous changes that occur with age, the etiology of sarcopenia remains unclear. However, recent characterizations of the aging muscle transcriptional landscape, signaling pathway disruptions, fiber and extracellular matrix compositions, systemic metabolomic and inflammatory responses, mitochondrial function, and neurological inputs offer insights and hope for future treatments. This review will discuss age-related changes in healthy muscle and our current understanding of how this can deteriorate into sarcopenia. As our elderly population continues to grow, we must understand sarcopenia and find treatments that allow individuals to maintain independence and dignity throughout an extended lifespan.

Inflammation-associated intramyocellular lipid alterations in human pancreatic cancer cachexia

BACKGROUND

Cancer cachexia is a multifactorial metabolic syndrome characterized by systemic inflammation and ongoing skeletal muscle loss resulting in weakness, poor quality of life, and decreased survival. Whereas lipid accumulation in skeletal muscle is associated with cancer cachexia as well as the prognosis of cancer patients, surprisingly little is known about the nature of the lipids that accumulate in the muscle during cachexia, and whether this is related to inflammation. We aimed to identify the types and distributions of intramyocellular lipids in patients with and without cancer cachexia.

METHODS

Rectus abdominis muscle biopsies were collected during surgery of patients with pancreatic ductal adenocarcinoma (n = 10 without cachexia, n = 20 cachectic without inflammation (CRP < 10 mg/L), n = 10 cachectic with inflammation (CRP ≥ 10 mg/L). L3-CT scans were analysed to assess body composition based on validated thresholds in Hounsfield units (HU). Muscle sections were stained with Oil-Red O and H&E to assess general lipid accumulation and atrophy. Untargeted lipidomic analyses were performed on laser-microdissected myotubes using LC-MS/MS. The spatial distribution of intramyocellular lipids with differential abundance between groups was visualized by mass-spectrometry imaging. Genes coding for inflammation markers and enzymes involved in de novo ceramide synthesis were studied by qPCR.

RESULTS

Muscle radiation attenuation was lower in cachectic patients with inflammation (median 24.3 [18.6-30.8] HU) as compared with those without inflammation (34.2 [29.3-38.7] HU, P = 0.033) or no cachexia (37.4 [33.9-42.9] HU, P = 0.012). Accordingly, intramyocellular lipid content was lower in non-cachectic patients (1.9 [1.6-2.1]%) as compared with those with cachexia with inflammation (5.5 [4.5-7.3]%, P = 0.002) or without inflammation (4.8 [2.6-6.0]%, P = 0.017). Intramyocellular lipid accumulation was associated with both local IL-6 mRNA levels (rs = 0.57, P = 0.015) and systemic CRP levels (rs = 0.49, P = 0.024). Compared with non-cachectic subjects, cachectic patients had a higher relative abundance of intramyocellular glycerophospholipids and a lower relative abundance of glycerolipids. Furthermore, increases in several intramyocellular lipids such as SM(d36:1), PC(34:1), and TG(48:1) were found in cachectic patients with inflammation and correlated with specific cachexia features. Altered intramyocellular lipid species such as PC(34:1), LPC(18:2), and TG(48:1) showed an uneven distribution in muscle sections of cachectic and non-cachectic patients, with areas featuring abundance of these lipids next to areas almost devoid of them.

CONCLUSIONS

Intramyocellular lipid accumulation in patients with cachexia is associated with both local and systemic inflammation, and characterized by changes in defined lipid species such as glycerolipids and glycerophospholipids.

Obesity-related glomerulopathy: recent advances in inflammatory mechanisms and related treatments

Obesity-related glomerulopathy, which is an obesity-triggered kidney damage, has become a significant threat to human health. Several studies have recently highlighted the critical role of inflammation in obesity-related glomerulopathy development. Additionally, excess adipose tissue and adipocytes in patients with obesity produce various inflammatory factors that cause systemic low-grade inflammation with consequent damage to vascular endothelial cells, exacerbating glomerular injury. Therefore, we conducted a comprehensive review of obesity-related glomerulopathy and addressed the critical role of obesity-induced chronic inflammation in obesity-related glomerulopathy pathogenesis and progression, which leads to tubular damage and proteinuria, ultimately impairing renal function. The relationship between obesity and obesity-related glomerulopathy is facilitated by a network of various inflammation-associated cells (including macrophages, lymphocytes, and mast cells) and a series of inflammatory mediators (such as tumor necrosis factor α, interleukin 6, leptin, adiponectin, resistin, chemokines, adhesion molecules, and plasminogen activator inhibitor 1) and their inflammatory pathways. Furthermore, we discuss a recently discovered relationship between micronutrients and obesity-related glomerulopathy inflammation and the important role of micronutrients in the body's anti-inflammatory response. Therefore, assessing these inflammatory molecules and pathways will provide a strong theoretical basis for developing therapeutic strategies based on anti-inflammatory effects to prevent or delay the onset of kidney injury.

Intestinal Dysbiosis in Subjects with Obesity from Western Mexico and Its Association with a Proinflammatory Profile and Disturbances of Folate (B9) and Carbohydrate Metabolism

Obesity is a public health problem with a growing prevalence worldwide. In Mexico, it is estimated that one out of three adults suffer from obesity. In these patients, the intestinal microbiota (IM) undergoes pathological changes that are associated with a dysbiotic state; however, the microbiota profile of adult subjects with obesity from western Mexico has not been described. To assess this, fecal samples were obtained from 65 participants (Obese = 38; Control = 27). The microbial composition was characterized by 16S rRNA amplicon sequencing. The IM of the group with obesity revealed a clear decrease in richness and diversity (p < 0.001), as well as a significant increase in proinflammatory bacterial groups, mainly genera belonging to the Negativicutes class, Escherichia/Shigella, and Prevotella. Likewise, an increase in short-chain fatty acid-producing bacteria was found, especially the genus Lachnoclostridium. Additionally, PICRUSt2 analysis showed a depletion of vitamin B9 metabolism and an increase in saccharolytic pathways. The IM of patients with obesity possesses a dysbiotic, proinflammatory environment, possibly contributing to lipogenesis and adiposity. Thus, assessing the IM will allow for a better understanding of the pathophysiology of metabolic diseases of high prevalence, such as obesity. These findings are described for the first time in the adult population of western Mexico.

Fatty Pancreas Is a Risk Factor for Pancreatic Cancer: A Systematic Review and Meta-Analysis of 2956 Patients

Pancreatic cancer (PC) is one of the most lethal cancers worldwide. Recently, fatty pancreas (FP) has been studied thoroughly, and although its relationship to PC is not fully understood, FP is suspected to contribute to the development of PC. We aimed to assess the association between PC and FP by conducting a systematic review and meta-analysis. We systematically searched three databases, MEDLINE, Embase, and CENTRAL, on 21 October 2022. Case-control and cross-sectional studies reporting on patients where the intra-pancreatic fat deposition was determined by modern radiology or histology were included. As main outcome parameters, FP in patients with and without PC and PC in patients with and without FP were measured. Proportion and odds ratio (OR) with a 95% confidence interval (CI) were used for effect size measure. PC among patients with FP was 32% (OR 1.32; 95% CI 0.42-4.16). However, the probability of having FP among patients with PC was more than six times higher (OR 6.13; 95% CI 2.61-14.42) than in patients without PC, whereas the proportion of FP among patients with PC was 0.62 (95% CI 0.42-0.79). Patients identified with FP are at risk of developing PC. Proper screening and follow-up of patients with FP may be recommended.

Fatty infiltration of the pancreas: a systematic concept analysis

Fatty infiltration of the pancreas (FIP) has been recognized for nearly a century, yet many aspects of this condition remain unclear. Regular literature reviews on the diagnosis, consequences, and management of FIP are crucial. This review article highlights the various disorders for which FIP has been established as a risk factor, including type 2 diabetes mellitus (T2DM), pancreatitis, pancreatic fistula (PF), metabolic syndrome (MS), polycystic ovary syndrome (PCOS), and pancreatic duct adenocarcinoma (PDAC), as well as the new investigation tools. Given the interdisciplinary nature of FIP research, a broad range of healthcare specialists are involved. This review article covers key aspects of FIP, including nomenclature and definition of pancreatic fat infiltration, history and epidemiology, etiology and pathophysiology, clinical presentation and diagnosis, clinical consequences, and treatment. This review is presented in a detailed narrative format for accessibility to clinicians and medical students.

Inhibition of DHCR24 activates LXRα to ameliorate hepatic steatosis and inflammation

Liver X receptor (LXR) agonism has theoretical potential for treating NAFLD/NASH, but synthetic agonists induce hyperlipidemia in preclinical models. Desmosterol, which is converted by Δ24-dehydrocholesterol reductase (DHCR24) into cholesterol, is a potent endogenous LXR agonist with anti-inflammatory properties. We aimed to investigate the effects of DHCR24 inhibition on NAFLD/NASH development. Here, by using APOE*3-Leiden. CETP mice, a well-established translational model that develops diet-induced human-like NAFLD/NASH characteristics, we report that SH42, a published DHCR24 inhibitor, markedly increases desmosterol levels in liver and plasma, reduces hepatic lipid content and the steatosis score, and decreases plasma fatty acid and cholesteryl ester concentrations. Flow cytometry showed that SH42 decreases liver inflammation by preventing Kupffer cell activation and monocyte infiltration. LXRα deficiency completely abolishes these beneficial effects of SH42. Together, the inhibition of DHCR24 by SH42 prevents diet-induced hepatic steatosis and inflammation in a strictly LXRα-dependent manner without causing hyperlipidemia. Finally, we also showed that SH42 treatment decreased liver collagen content and plasma alanine transaminase levels in an established NAFLD model. In conclusion, we anticipate that pharmacological DHCR24 inhibition may represent a novel therapeutic strategy for treatment of NAFLD/NASH.

Anthocyanin supplementation improves obesity-related inflammatory characteristics: A systematic review and meta-analysis of randomized controlled trials

The relationship between anthocyanin intake and obesity-related inflammatory markers remains unclear in existing research. To investigate this, we hypothesized that anthocyanin supplementation could reduce plasma concentrations of inflammatory markers, including C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), vascular cell adhesion molecule-1, and other cytokines in obesity. We conducted a systematic search of PubMed, Web of Science, Scopus, SinoMed, and other related literature and identified 16 randomized controlled trials that met our inclusion criteria. Our findings showed that anthocyanin intake was significantly associated with a reduction in vascular cell adhesion molecule-1 mean plasma concentrations (-53.56 ng/mL; 95% confidence interval [CI], -82.10 to -25.03). We also observed a modest decrease in CRP (-0.27 ng/mL; 95% CI, -0.58 to 0.05), TNF-α (-0.20 ng/mL; 95% CI, -0.54 to 0.15), and IL-6 (-0.53 ng/mL; 95% CI, -1.16 to 0.10) mean plasma concentrations. Subgroup analysis revealed that anthocyanin intake tended to decrease CRP and IL-6 concentrations in overweight or dyslipidemic individuals. Additionally, the intervention duration subgroup analysis showed that anthocyanin supplementation had a stronger effect on plasma IL-6 and TNF-α in participants after 8 to 12 weeks of intervention. In conclusion, our meta-analysis indicated that anthocyanin supplementation can effectively reduce obesity-related inflammatory markers associated with chronic low-grade inflammation.

Disrupted leptin-fatty acid biosynthesis is an early manifestation of metabolic abnormalities in schizophrenia

BACKGROUND

Insulin resistance (IR) and impaired energy expenditure (IEE) are irreparable metabolic comorbidities in schizophrenia. Although mechanism(s) underlying IR and IEE remains unclear, leptin and fatty acid signaling, which has profound influence on insulin secretion/sensitivity, glucose metabolism and energy expenditure, could be disrupted. However, no association of plasma leptin with erythrocyte membrane fatty acids, body mass index (BMI), and psychotic symptoms in the same cohort of untreated patients with first-episode psychosis (FEP) or medicated patients with chronic schizophrenia (CSZ) is presented before. These studies are crucial for deciphering the role of leptin and fatty acids in the development of IR and IEE in schizophrenia.

AIM

To determine the association between plasma leptin, erythrocyte membrane fatty acids, particularly, saturated fatty acids (SFAs), BMI and psychotic symptoms in patients with FEP and CSZ.

METHODS

In this study, twenty-two drug naive patients with FEP, twenty-one CSZ patients treated with atypical antipsychotic drugs, and fourteen healthy control (CNT) subjects were analyzed. Plasma leptin was measured using sandwich mode enzyme-linked immunosorbent assay. Erythrocyte membrane SFAs were measured using ultrathin capillary gas chromatography. BMI was calculated by using the formula: weight (kg)/height (m²). Psychiatric symptoms were evaluated at baseline using brief psychiatric rating scale (BPRS), and positive and negative syndrome scale (PANSS). The total BPRS scores, positive and negative symptom scores (PANSS-PSS and PANSS-NSS, respectively) were recorded. Pearson correlation coefficient (r) analyses were performed to find the nature and strength of association between plasma leptin, PANSS scores, BMI and SFAs, particularly, palmitic acid (PA).

RESULTS

In patients with FEP, plasma leptin not BMI was significantly lower (P = 0.034), whereas, erythrocyte membrane SFAs were significantly higher (P < 0.005) compared to the CNT subjects. Further, plasma leptin showed negative correlation with erythrocyte membrane SFAs-PA (r = −0.4972, P = 0.001), PANSS-PSS (r = −0.4034, P = 0.028), and PANSS-NSS (r = −0.3487, P = 0.048). However, erythrocyte membrane SFAs-PA showed positive correlation with PANSS-PSS (r = 0.5844, P = 0.0034) and PANSS-NSS (r = 0.5380, P = 0.008). In CSZ patients, plasma leptin, BMI, and erythrocyte membrane SFAs, all were significantly higher (P < 0.05) compared to the CNT subjects. Plasma leptin showed positive correlation with BMI (r = 0.312, P = 0.032) but not with PANSS scores or erythrocyte membrane SFAs-PA. However, erythrocyte membrane SFAs-PA showed positive correlation with PANSS-NSS only (r = 0.4729, P = 0.031). Similar changes in the plasma leptin and erythrocyte membrane SFAs have also been reported in individuals at ultra-high risk of developing psychosis; therefore, the above findings suggest that leptin-fatty acid biosynthesis could be disrupted before the onset of psychosis in schizophrenia.

CONCLUSION

Disrupted leptin-fatty acid biosynthesis/signaling could be an early manifestation of metabolic comorbidities in schizophrenia. Large-scale studies are warranted to validate the above findings.

Partial Replacement of Dietary Fat with Krill Oil or Coconut Oil Alleviates Dyslipidemia by Partly Modulating Lipid Metabolism in Lipopolysaccharide-Injected Rats on a High-Fat Diet

This study investigated the effects of partial replacement of dietary fat with krill oil (KO) or coconut oil (CO) on dyslipidemia and lipid metabolism in rats fed with a high-fat diet (HFD). Sprague Dawley rats were divided into three groups as follows: HFD, HFD + KO, and HFD + CO. The rats were fed each diet for 10 weeks and then intraperitoneally injected with phosphate-buffered saline (PBS) or lipopolysaccharide (LPS) (1 mg/kg). The KO- and CO-fed rats exhibited lower levels of serum lipids and aspartate aminotransferases than those of the HFD-fed rats. Rats fed with HFD + KO displayed significantly lower hepatic histological scores and hepatic triglyceride (TG) content than rats fed with HFD. The KO supplementation also downregulated the adipogenic gene expression in the liver. When treated with LPS, the HFD + KO and HFD + CO groups reduced the adipocyte size in the epididymal white adipose tissues (EAT) relative to the HFD group. These results suggest that KO and CO could improve lipid metabolism dysfunction.

Pancreatic steatosis: A frequent finding in a Chilean population

INTRODUCTION AND AIMS

Pancreatic steatosis is an incidental radiologic finding in asymptomatic patients, and its clinical importance is unclear. Primary aim: to study the prevalence of pancreatic steatosis (PS) in consecutive patients registered at our hospital, that underwent computed axial tomography (CAT) scanning of the abdomen and pelvis, excluding known pancreatic diseases. Secondary aim: to review the association of PS with the demographic and clinical data of the patients, as well as with hepatic steatosis (HS).

MATERIALS AND METHODS

An observational study was conducted on adult patients that had CAT scans of the abdomen and pelvis.

DEFINITIONS

a) tissue density was measured in Hounsfield units (HU) in five 1 cm² areas of the pancreas, three areas of the spleen, and in segments VI and VII of the liver; b) fatty pancreas: a difference < -10 HU between the mean pancreas and mean spleen densities; and c) fatty liver: density < 40 HU. We registered the epidemiologic and laboratory data of the patients. The association of those factors with the presence of PS was analyzed using SPSS version 24.0 software, and statistical significance was set at a p < 0.05.

RESULTS

Of the 203 patients, PS was found in 61 (30%). The patients with PS were significantly older and had a higher body mass index. We found no significant association with the rest of the parameters studied, nor with HS (55 patients). None of the patients had symptoms attributable to a disease of the exocrine pancreas.

CONCLUSIONS

Fatty infiltration of the pancreas is a frequent finding in CAT scans, and its clinical importance is unclear. Aging of the population and the increase in obesity underline the need for future studies on PS.

Patchouli alcohol ameliorates skeletal muscle insulin resistance and NAFLD via AMPK/SIRT1-mediated suppression of inflammation

Obesity-induced chronic low-grade inflammation and thus causes various metabolic diseases, such as insulin resistance and non-alcoholic fatty liver disease (NAFLD). Patchouli alcohol (PA), an active component extracted from patchouli, displayed anti-inflammatory effects on different cell types. However, the impact of PA on skeletal muscle insulin signaling and hepatic lipid metabolism remains unclear. This study aimed to investigate whether PA would affect insulin signaling impairment in myocytes and lipid metabolism in hepatocytes. Treatment with PA ameliorated palmitate-induced inflammation and aggravation of insulin signaling in C2C12 myocytes and lipid accumulation in HepG2 hepatocytes. Treatment of C2C12 myocytes and HepG2 cells with PA augmented AMP-activated protein kinase (AMPK) phosphorylation and Sirtuin 1 (SIRT1) expression in a dose-dependent manner. siRNA-mediated suppression of AMPK or SIRT1 mitigated the effects of PA on palmitate-induced inflammation and insulin resistance in C2C12 myocytes and lipid accumulation in HepG2 cells. Animal experiments demonstrated that PA administration increased AMPK phosphorylation and SIRT1 expression, and ameliorated inflammation, thereby attenuating skeletal muscle insulin resistance and hepatic steatosis in high-fat diet-fed mice. These results denote that PA alleviates skeletal muscle insulin resistance and hepatic steatosis through AMPK/SIRT1-dependent signaling. This study might provide a novel therapeutic approach for treating obesity-related insulin resistance and NAFLD.

Modulation of endothelium function by fatty acids

The endothelium acts as the barrier that prevents circulating lipids such as lipoproteins and fatty acids into the arterial wall; it also regulates normal functioning in the circulatory system by balancing vasodilation and vasoconstriction, modulating the several responses and signals. Plasma lipids can interact with endothelium via different mechanisms and produce different phenotypes. Increased plasma-free fatty acids (FFAs) levels are associated with the pathogenesis of atherosclerosis and cardiovascular diseases (CVD). Because of the multi-dimensional roles of plasma FFAs in mediating endothelial dysfunction, increased FFA level is now considered an essential link in the onset of endothelial dysfunction in CVD. FFA-mediated endothelial dysfunction involves several mechanisms, including dysregulated production of nitric oxide and cytokines, metaflammation, oxidative stress, inflammation, activation of the renin-angiotensin system, and apoptosis. Therefore, modulation of FFA-mediated pathways involved in endothelial dysfunction may prevent the complications associated with CVD risk. This review presents details as to how endothelium is affected by FFAs involving several metabolic pathways.

Macrophage migration inhibitory factor deficiency aggravates effects of fructose-enriched diet on lipid metabolism in the mouse liver

Dietary fructose can disturb hepatic lipid metabolism in a way that leads to lipid accumulation and steatosis, which is often accompanied with low-grade inflammation. The macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine with important role not only in the regulation of inflammation, but also in the modulation of energy metabolism in the liver. Thus, the aim of this study was to investigate the role of Mif deficiency in fructose-induced disturbances of hepatic lipid metabolism and ectopic lipid accumulation. Wild type (WT) and Mif deficient (MIF^-/- ) C57Bl/6J mice were used to analyze the effects of 9-week 20% fructose-enriched diet on hepatic lipid metabolism (both lipogenesis and β-oxidation) and histology, inflammatory status and glucocorticoid receptor (GR) signaling. The results showed fructose-induced elevation of lipogenic genes (fatty acid synthase (Fas) and stearoyl-CoA desaturase-1 (Scd1) and transcriptional lipogenic regulators (liver X receptor (LXR), sterol regulatory element binding protein 1c (SREBP1c), and carbohydrate response element-binding protein (ChREBP)). However, microvesicular fatty changes, accompanied with enhanced inflammation, were observable only in fructose-fed Mif deficient animals, and were most likely result of GR activation and facilitated uptake and decreased β-oxidation of FFA, as evidenced by elevated protein level of fatty acid translocase (FAT/CD36) and decreased carnitine palmitoyl transferase 1 (CPT1) level. In conclusion, the results show that Mif deficiency aggravates the effects of energy-rich fructose diet on hepatic lipid accumulation, most likely through enhanced inflammation and activation of GR signaling pathway.

Association between High-Sensitive C-Reactive Protein and the Development of Liver Damage in Japanese Male Workers

BACKGROUND

The aim of this study was to determine whether a causative relationship exists between the development of liver damage and increased high-sensitivity C-reactive protein (HsCRP) levels by long-term follow-up in Japanese workers.

METHODS

The target participants comprised 7830 male workers in a Japanese steel company. The prospective cohort study was performed over a 6-year period, and annual health screening information was analyzed by pooled logistic regression. The endpoint, regarded as the development of liver damage, was defined as aspartate aminotransferase (AST) ≥ 40 IU/L.

RESULTS

A significant relationship between the development of liver damage and increased HsCRP levels was observed after adjusting for confounding factors such as various physiological and blood chemistry parameters and lifestyle factors. The odds ratio of a 1.5-fold increase in HsCRP was 1.07 (95% confidence interval: 1.03-1.10, p < 0.001).

CONCLUSIONS

The results suggested that an increase of HsCRP is associated with the development of liver damage.

Lipidomics Revealed Aberrant Metabolism of Lipids Including FAHFAs in Renal Tissue in the Progression of Lupus Nephritis in a Murine Model

Lupus nephritis (LN) is an inflammatory renal disease of patients with systemic lupus erythematosus with lots of immune complexes deposited in kidneys. Accumulated studies have demonstrated the close relationships among dyslipidaemia, inflammation, and autoimmune response, and oxidative stress in the patients. Lipids play numerous important roles in biological process and cellular functions. Herein, shotgun lipidomics was employed to quantitatively analyze cellular lipidomes in the renal tissue of MRL/lpr mice in the progression of LN (including pre-LN and LN state) with/without treated with glucocorticoids (GCs). The levels of cytokines (i.e., TNF-α (Tumor necrosis factor alpha) and IL-6 (Interleukin 6)) in the serum were measured by ELISA (enzyme-linked immunosorbent assay) kits. Renal histopathological changes and C3 deposition in the glomeruli of the mice were also determined. Lipidomics analysis revealed that the ectopic fat deposition and the aberrant metabolism of lipids that were relevant to oxidative stress (e.g., 4-hydroxyalkenal, ceramide, lysophospholipid species, etc.) always existed in the development of LN. Moreover, the anti-inflammatory FAHFA (fatty acid ester of hydroxyl fatty acid) species in the kidney tissue could largely reflect the severity of LN. Thus, they were a potential early biomarker for LN. In addition, the study also revealed that treatment with GCs could prevent the progression of LN, but greatly aggravate the aberrant metabolism of the lipids, particularly when used for a long time.

IL-10 Deficiency Aggravates Renal Inflammation, Fibrosis and Functional Failure in High-Fat Dieted Obese Mice

BACKGROUND:

High-fat diet-induced obesity is one of the major cause of chronic renal failure. This obesity-related renal failure is mainly caused by inflammatory processes. However, the role of the major anti-inflammatory cytokine interleukin (IL)-10 has not been researched intensively.

METHODS:

To evaluate the effect of IL-10 deficiency on obesity-related renal failure, the in vivo study was carried with four animal groups; (1) Low-fat dieted C57BL/6 mice, (2) Low-fat dieted IL-10 knockout (KO) mice, (3) High‐fat dieted C57BL/6 mice and (4) High‐fat dieted IL-10 KO mice group. The analysis was carried with blood/urine chemistry, H&E, Oil-Red-O, periodic acid-Schiff and Masson’s trichrome staining immunohistochemistry and real-time PCR methods.

RESULTS:

At week 12, high‐fat dieted IL-10 KO mice showed 1) severe lipid accumulation in kidneys, cholesterol elevation (in total, serum kidney) and low-density lipoprotein increasion through the SCAP-SREBP2-LDLr pathway; (2) serious histopathologic alterations showing glomerulosclerosis, tubulointerstitial fibrosis and immune cell infiltration; (3) increased pro‐inflammatory cytokines and chemokines expression; (4) enhanced renal fibrosis; and (5) serious functional failure with high serum creatinine and BUN and proteinuria excretion compared to other groups.

CONCLUSION:

IL-10 deficiency aggravates renal inflammation, fibrosis and functional failure in high-fat dieted obese mice, thus IL-10 therapy could be applied to obesity-related chronic renal failure.

Lutein attenuates excessive lipid accumulation in differentiated 3T3-L1 cells and abdominal adipose tissue of rats by the SIRT1-mediated pathway

OBJECTIVE

Obesity is now a worldwide disease and is mainly attributable to increased body fat deposition. In a growing number of epidemiological studies, lutein has been revealed to have different degrees of anti-obesity properties, but the potential underlying mechanisms that have been reported are limited. Therefore, we aimed to clarify the protective effects of lutein against excessive lipid accumulation, and we explored the role of SIRT1 and SIRT1-mediated pathways both in abdominal adipose tissue and mature 3T3-L1 cells during lutein administration.

METHODS

In our design, male Sprague-Dawley rats were fed either control or high-fat diets with or without 25 mg/kg·bw/day lutein for 5 weeks. Additionally, differentiated 3T3-L1 cells were incubated with 40 μM lutein or 10 μM Ex527 for 24 h.

RESULTS

Lutein supplementation decreased the body weight, abdominal fat index ratio, frequency and mean area of larger adipocytes in HE staining induced by the high-fat diet and then activated the expression of SIRT1 and thus upregulated FoxO1, ATGL, and HSL expression and downregulated SREBP-1, FAS, and ACC expression both in abdominal adipose tissue and differentiated 3T3-L1 cells. However, coincubation with Ex527 and lutein suppressed the activation of SIRT1 and reversed the expression of FoxO1, ATGL, HSL, SREBP-1, FAS, and ACC in comparison to those in the Lut group.

CONCLUSIONS

Overall, we suggest that the effects of lutein on attenuating excessive lipid accumulation are dependent on the SIRT1-mediated pathway in vivo and in vitro, which indicates that lutein administration may be a potential strategy for preventing excessive lipid accumulation and obesity.

Neglected extra-articular manifestations in rheumatoid arthritis patients with normal body mass index: reduced skeletal muscle overlapping overfat

Background:

Chronic inflammation in rheumatoid arthritis (RA) can induce reduced muscle mass (myopenia) and ectopic fat deposition probably showing normal body mass index (BMI). We aimed to investigate their body composition (BC) characteristics and clinical significance.

Methods:

BMI and BC were collected in consecutive RA patients and control subjects. Myopenia was defined by appendicular skeletal muscle mass index (ASMI) ⩽7.0 kg/m² in men and ⩽5.7 kg/m² in women. Overfat was defined by body fat percentage (BF%) as ⩾25% for men and ⩾35% for women.

Results:

There were 620 RA patients (57.6% with normal BMI) and 2537 control subjects (62.5% with normal BMI) recruited. After 1:1 age and sex matching with control subjects, RA patients with normal BMI (n = 240) showed significantly higher prevalence of myopenia (43.3% versus 22.1%) and overfat (19.2% versus 7.1%) as well as myopenia overlapping overfat (17.1% versus 3.3%). In all RA patients with normal BMI (n = 357), there were 18.2% patients with myopenia overlapping overfat who had the worst radiographic scores and highest rates of previous glucocorticoid treatment and hypertension. Compared with those without, normal BMI RA patients with previous glucocorticoid treatment (24.4% versus 10.3%) or hypertension (27.8% versus 13.6%) had a higher rate of myopenia overlapping overfat. Previous glucocorticoid treatment [odds ratio (OR) = 2.844, 95% confidence interval (CI) 1.441–5.614] and hypertension (OR = 2.452, 95% CI 1.283–4.685) were potential associated factors of myopenia overlapping overfat in RA patients with normal BMI.

Conclusion:

Myopenia overlapping overfat is an important extra-articular manifestation which should not be ignored in RA patients with normal BMI, especially with glucocorticoid treatment and hypertension.

Adipose-derived stem cell therapy shows promising results for secondary lymphedema

Lymphedema is mainly identified by progressive soft tissue swelling in impaired lymphatic system. Secondary lymphedema attributed to cancer therapy, parasite infection, and trauma remains a serious global disease. Patients with lymphedema suffer swelling, pain, and fatigue, with the dysfunction of the deformed extremities reducing the quality of life and increasing the risk of infection and lymphangiosarcoma. Adipose-derived stem cells (ADSCs) possess prominent regenerative potential to differentiate into multilineage cells, and produce various lymphangiogenic factors, making ADSC therapy a promising approach for lymphedema. The development of lymphedema consists of local inflammation, the fibrosis of lymphatic vessels, and the deposition of adipose fat. Existing animal models do not mimic the chronic inflammation environment, therefore suitable models are required in further studies. Some signal pathways and molecular mechanisms in physiological and pathological lymphagiogenesis remain unclear. In previous animal and human trials, ADSC therapy reduced edema in varying degrees. A larger number of trials with larger samples and longer follow-up periods are required to verify the efficiency and feasibility of ADSC therapy. ADSCs are of easy availability and immune exemption, making them a candidate for lymphedema treatment. Whether ADSCs enhance malignant characteristics or trigger the malignant change deserves further exploration and study before ADSC therapy can be made widely available.

P2X7 Receptor in the Management of Energy Homeostasis: Implications for Obesity, Dyslipidemia, and Insulin Resistance

Whole-body energy metabolism entails the highly regulated balance between food intake, nutrient breakdown, energy generation (ATP), and energy storage for the preservation of vital functions and body mass. Purinergic signaling has attracted increasing attention in the regulatory mechanisms not only for the reverse processes of white adipose tissue lipogenesis and lipolysis, but also for brown adipocyte-dependent thermogenesis and leptin production. This regulatory role has remarkable implications in the handling of body's energy expenditure and energy reservoir. Hence, selected purinergic receptors can play a relevant function in lipid metabolism, endocrine activity, glucose uptake, ATP-dependent increased expression of uncoupling protein 1, and browning of adipose tissue. Indeed, purinergic P2 receptors regulate adipogenesis and lipid metabolism and are involved in adipogenic differentiation. In particular, the ionotropic ATP-activated P2X7 subtype is involved in fat distribution, as well as in the modulation of inflammatory pathways in white adipose tissue. Within this context, very recent evidence has established a direct function of P2X7 in energy metabolism. Specifically, either genetic deletion (P2X7 knockout mice) or subchronic pharmacological inhibition of the receptor produces a decrease of whole-body energy expenditure and, concurrently, an increase of carbohydrate oxidation. As further evidence, lipid accumulation, increased fat mass distribution, and weight gain are reported in P2X7-depleted mice. Conversely, the stimulation of P2X7 enhances energy expenditure. Altogether, this knowledge supports the role of P2X7 signaling in the fight against obesity and insulin resistance, as well as in the promotion of adaptive thermogenesis.

Differential impacts of late gestational over-and undernutrition on adipose tissue traits and associated visceral obesity risk upon exposure to a postnatal high-fat diet in adolescent sheep

We hypothesized that late gestation malnutrition differentially affects expandability of adipose tissues to predispose for early postnatal visceral adiposity. Twin-lambs born to dams fed HIGH (150%/110% of required energy/protein, respectively), NORM (100% of requirements) or LOW (50% of NORM) diets during the last trimester were used. Postnatally, lambs were raised on moderate (CONV) or high-carbohydrate-high-fat (HCHF) diets. Adipose tissues were sampled at autopsy at 6 months of age (~puberty) to characterize cellularity, adipocyte cross-sectional area and gene expression patterns. HIGH and LOW compared to NORM lambs had reduced intrinsic (under CONV diet) cellularity in subcutaneous and mesenteric (particularly LOW), and reduced obesity-induced (under HCHF diet) hyperplasia in subcutaneous, mesenteric and perirenal (particularly HIGH) adipose tissues. This corresponded with more pronounced HCHF diet-induced hypertrophy in mesenteric (particularly LOW), perirenal (particularly HIGH) and subcutaneous (particularly HIGH) adipose tissues, and tissue-specific reductions in mRNA expressions for lipid metabolism, angiogenesis and adipose development. Gene expression for inflammation and lipid metabolism markers were increased and decreased, respectively, in HCHF lambs (HCHF lambs became obese) in all tissues. Both prenatal over- and undernutrition predisposed for abdominal adiposity and extreme perirenal hypertrophy due to reduced intrinsic (observed under CONV diet) cellularity and impaired ability of subcutaneous, mesenteric and perirenal adipose tissues to expand by hyperplasia rather than hypertrophy on an obesogenic (HCHF) diet.

Pancreatic Steatosis: An Emerging Clinical Entity

Pancreatic steatosis is an emerging clinical entity whose pathophysiology, natural history, and long-term complications are poorly characterized in the current literature. Epidemiological and prospective studies have described prevalence rates between 16% and 35%. Although the natural history is not well known, there are strong associations with obesity, metabolic syndrome, type 2 diabetes mellitus, and nonalcoholic fatty liver disease. Ectopic fat accumulation of the pancreas can cause chronic, low-grade inflammation from adipocytokine imbalances that involve beta cells and acinar cells. This mechanism can lead to pancreatic endocrine and exocrine dysfunction and initiate carcinogenesis. Although it is associated with morbid conditions, pancreatic steatosis may be amendable to treatment with a healthy diet, less meat consumption, exercise, and smoking cessation. Pancreatic steatosis should factor into clinical decision-making and prognostication of patients with pancreatic and systemic disease. This review seeks to describe the pathophysiology, natural history, diagnosis, and complications of this emerging clinically relevant entity.

Pancreatic steatosis: an update

PURPOSE OF REVIEW

Pancreatic steatosis is a clinical entity with emerging significance and impacts patient health in a multitude of ways. It has a high prevalence in the global population with predilections for different demographics by age, sex and ethnicity. Understanding the pathophysiology, clinical features and complications of this entity may be important to understanding the consequences of the ongoing obesity global epidemic.

RECENT FINDINGS

Obesity and metabolic syndrome contribute to metabolic derangements that result in lipid mishandling by adipocytes. Adipocytokine imbalances in circulation and in the pancreatic microenvironment cause chronic, low-grade inflammation. The resulting beta cell and acinar cell apoptosis leads to pancreatic endocrine and exocrine dysfunction. Furthermore, these adipocytokines regulate cell growth, differentiation, as well as angiogenesis and lymphatic spread. These consequences of adipocyte infiltration are thought to initiate carcinogenesis, leading to pancreatic intraepithelial neoplasia and pancreatic ductal adenocarcinoma.

SUMMARY

Obesity will lead to millions of deaths each year and pancreatic steatosis may be the key intermediate entity that leads to obesity-related complications. Enhancing our understanding may reveal strategies for preventing mortality and morbidity related to the global epidemic of obesity. Further research is needed to determine the pathophysiology, long-term complications and effective treatment strategies for this condition.

Hot Water Extract of Curcuma longa L. Improves Serum Inflammatory Markers and General Health in Subjects with Overweight or Prehypertension/Mild Hypertension: A Randomized, Double-Blind, Placebo-Controlled Trial

To investigate the effect of a hot water extract of C. longa L. (WEC) containing anti-inflammatory agents, bisacurone, and turmeronol on chronic inflammation, a randomized double-blind placebo-controlled study was conducted in middle-aged and elderly subjects aged 50–69 years with overweight or prehypertension/mild hypertension. The subjects consumed 900 mg WEC tablets, containing 400 μg bisacurone, 80 μg turmeronol A and 20 μg turmeronol B (WEC group: n = 45), or placebo tablets without WEC (placebo group: n = 45) daily for 12 weeks. Serum inflammatory and metabolic markers were measured. The subjects also completed the MOS 36-item short-form health survey (SF-36) and the Profile of Mood States scale (POMS). In the WEC group, the serum levels of C-reactive protein, tumor necrosis factor-α, interleukin-6, and soluble vascular cell adhesion molecule-1 decreased significantly. Compared with the placebo group, the WEC group had significantly lower serum levels of glucose, hemoglobin A1c, and triglycerides, as well as higher serum levels of high-density lipoprotein cholesterol. The WEC group also showed significant improvement of SF-36 scores (for general health, vitality, mental health, and mental summary component) and POMS scores for positive mood states (vigor-activity and friendliness). In conclusion, WEC may ameliorate chronic low-grade inflammation, thus contributing to the improvement of associated metabolic disorders and general health.

Adipose Tissue Dysfunction as Determinant of Obesity-Associated Metabolic Complications

Obesity is a critical risk factor for the development of type 2 diabetes (T2D), and its prevalence is rising worldwide. White adipose tissue (WAT) has a crucial role in regulating systemic energy homeostasis. Adipose tissue expands by a combination of an increase in adipocyte size (hypertrophy) and number (hyperplasia). The recruitment and differentiation of adipose precursor cells in the subcutaneous adipose tissue (SAT), rather than merely inflating the cells, would be protective from the obesity-associated metabolic complications. In metabolically unhealthy obesity, the storage capacity of SAT, the largest WAT depot, is limited, and further caloric overload leads to the fat accumulation in ectopic tissues (e.g., liver, skeletal muscle, and heart) and in the visceral adipose depots, an event commonly defined as “lipotoxicity.” Excessive ectopic lipid accumulation leads to local inflammation and insulin resistance (IR). Indeed, overnutrition triggers uncontrolled inflammatory responses in WAT, leading to chronic low-grade inflammation, therefore fostering the progression of IR. This review summarizes the current knowledge on WAT dysfunction in obesity and its associated metabolic abnormalities, such as IR. A better understanding of the mechanisms regulating adipose tissue expansion in obesity is required for the development of future therapeutic approaches in obesity-associated metabolic complications.

Visceral adipose tissue is associated with poor diet quality and higher fasting glucose in adults with cystic fibrosis

BACKGROUND

Body fat distribution and diet quality influence clinical outcomes in general populations but are understudied in individuals with cystic fibrosis (CF). The aim of this pilot study was to assess body fat distribution and diet quality in relation to fasting glucose and lung function in adults with CF.

METHODS

Subjects were 24 adults (ages 18-50) with CF and 25 age-matched controls. The Healthy Eating Index 2015 (HEI-2015) was calculated from 3-day food records and data were adjusted per 1000 kcal. Whole and regional body composition, including visceral adipose tissue (VAT), was assessed by dual energy X-ray absorptiometry.

RESULTS

Subjects with CF reported more added sugar intake [26.1 (IQR 18.1) vs. 12.9 (12.5) g/1000 kcal, p < 0.001] and had lower HEI-2015 scores [48.3 (IQR 9.9) vs. 63.9 (27.3), p < 0.001] compared to controls. There were no differences in BMI, total body fat, or lean body mass (LBM) between subjects with CF and controls (p > 0.05 for all), although subjects with CF had higher VAT than control subjects [0.3 (IQR 0.3) vs 0.1 (0.3) kg, p = 0.02]. Among subjects with CF, VAT was positively associated with added sugar intake (p < 0.001) and fasting blood glucose (p = 0.04). Lung function was positively associated with BMI (p = 0.005) and LBM (p = 0.03) but not with adiposity indicators.

CONCLUSIONS

These novel data link body fat distribution with diet quality and fasting glucose levels in adults with CF, whereas LBM was associated with lung function. This study highlights the importance of increasing diet quality and assessing body composition and fat distribution in the CF population.

Impaired Adipogenesis and Dysfunctional Adipose Tissue in Human Hypertrophic Obesity

The subcutaneous adipose tissue (SAT) is the largest and best storage site for excess lipids. However, it has a limited ability to expand by recruiting and/or differentiating available precursor cells. When inadequate, this leads to a hypertrophic expansion of the cells with increased inflammation, insulin resistance, and a dysfunctional prolipolytic tissue. Epi-/genetic factors regulate SAT adipogenesis and genetic predisposition for type 2 diabetes is associated with markers of an impaired SAT adipogenesis and development of hypertrophic obesity also in nonobese individuals. We here review mechanisms for the adipose precursor cells to enter adipogenesis, emphasizing the role of bone morphogenetic protein-4 (BMP-4) and its endogenous antagonist gremlin-1, which is increased in hypertrophic SAT in humans. Gremlin-1 is a secreted and a likely important mechanism for the impaired SAT adipogenesis in hypertrophic obesity. Transiently increasing BMP-4 enhances adipogenic commitment of the precursor cells while maintained BMP-4 signaling during differentiation induces a beige/brown oxidative phenotype in both human and murine adipose cells. Adipose tissue growth and development also requires increased angiogenesis, and BMP-4, as a proangiogenic molecule, may also be an important feedback regulator of this. Hypertrophic obesity is also associated with increased lipolysis. Reduced lipid storage and increased release of FFA by hypertrophic SAT are important mechanisms for the accumulation of ectopic fat in the liver and other places promoting insulin resistance. Taken together, the limited expansion and storage capacity of SAT is a major driver of the obesity-associated metabolic complications.

Mechanosensitive Ion Channel Piezo1 Regulates Diet-Induced Adipose Inflammation and Systemic Insulin Resistance

Adipocytes function as an energy buffer and undergo significant size and volume changes in response to nutritional cues. This adipocyte plasticity is important for systemic lipid metabolism and insulin sensitivity. Accompanying the adipocyte size and volume changes, the mechanical pressure against cell membrane also changes. However, the role that mechanical pressure plays in lipid metabolism and insulin sensitivity remains to be elucidated. Here we show that Piezo1, a mechanically-activated cation channel stimulated by membrane tension and stretch, was highly expressed in adipocytes. Adipose Piezo1 expression was increased in obese mice. Adipose-specific piezo1 knockout mice (adipose-Piezo1^-/-) developed insulin resistance, especially when challenged with a high-fat diet (HFD). Perigonadal white adipose tissue (pgWAT) weight was reduced while pro-inflammatory and lipolysis genes were increased in the pgWAT of HFD-fed adipose-Piezo1^-/- mice. The adipose-Piezo1^-/- mice also developed hepatic steatosis with elevated expression of fatty acid synthesis genes. In cultured adipocytes, Piezo1 activation decreased, while Piezo1 inhibition elevated pro-inflammatory gene expression. TLR4 antagonist TAK-242 abolished adipocyte inflammation induced by Piezo1 inhibition. Thus, adipose Piezo1 may serve as an adaptive mechanism for adipocyte plasticity restraining pro-inflammatory response in obesity.

Ascorbic Acid Attenuates Multifidus Muscles Injury and Atrophy After Posterior Lumbar Spine Surgery by Suppressing Inflammation and Oxidative Stress in a Rat Model

STUDY DESIGN

A rat model of multifidus muscles injury and atrophy after posterior lumbar spine surgery.

OBJECTIVE

We determined the effect of ascorbic acid (AA) on the postoperative multifidus muscles in rat model.

SUMMARY OF BACKGROUND DATA

Previous studies show oxidative stress and inflammation are two main molecular mechanisms in multifidus muscle injury and atrophy after posterior lumbar surgery. AA may have a protective effect in postoperative multifidus muscles.

METHODS

Rats were divided into sham surgery, control surgery, and surgery plus AA groups. Multifidus muscles of the control and AA groups were excised from the osseous structures. The muscles were retracted continuously for 2 hours. In the sham and AA groups, AA was administered via oral gavage daily in the first week. In each group, the oxidative stress was evaluated by measuring malondialdehyde (MDA) and Total superoxide dismutase (T-SOD). The inflammation, fat degeneration, or fibrosis of multifidus muscle were evaluated by quantitative real-time polymerase chain reaction (q-PCR), histology, or immunohistochemical analysis.

RESULTS

T-SOD activity was significantly lower in the control group than that in the AA group in the first week. MDA levels were significantly higher in the AA group. Interleukin-6 and tumor necrosis factor-α in multifidus muscles also showed significant differences when treated with AA. The inflammation score on histology was significantly lower in the AA group postoperatively in the first week. In the long run, marker genes for fibrosis and fat degeneration, and fibrosis and fat degeneration scores, were significantly lower in the AA than the control group on days 14 and 28 postoperatively.

CONCLUSION

In conclusion, AA attenuated the oxidative stress and inflammation response in the postoperative multifidus muscles, and remarkable differences were observed from the histological assessment and related marker genes expression. Our results provided important insight into the anti-inflammatory and anti-oxidative effects of AA in the postoperative multifidus muscles.

LEVEL OF EVIDENCE

N/A.

Relationship Between Handgrip Strength and Nonalcoholic Fatty Liver Disease: Nationwide Surveys

BACKGROUND

The association of handgrip strength with nonalcoholic fatty liver disease (NAFLD) has not been studied yet. This study investigated the relationship between handgrip strength and NAFLD in South Korean adults.

METHODS

Referring to the Korea National Health and Nutrition Examination Survey 2014 and 2015 database, South Korean adults (n = 8001, women: 55.5%) aged 19-80 years having complete data were considered for this study. Relative handgrip strength (RHGS) [average handgrip strength of both hands divided by body mass index (BMI)], hepatic steatosis index (HSI), BMI, and components of metabolic syndrome were measured. Demographics, treatment of concurrent illnesses, and health-related behaviors were assessed by using standardized questionnaires. NAFLD was defined by the HSI >36.0, alcohol consumption <20 grams/day, and negative biomarkers for chronic hepatitis B and C.

RESULTS

The prevalence of NAFLD was 30.3% ± 0.7%. Complex sample logistic regression analysis revealed that individuals with lower RHGS [per 1 standard deviation (SD) decrease] manifested higher odds of suffering from NAFLD (adjusted odds ratio: 1.47, 95% confidence interval: 1.35-1.60). Furthermore, lower RHGS was associated with higher odds for NAFLD throughout the strata of sex, age group, education, BMI category, metabolic syndrome, treatment history of illnesses, smoking status, alcohol consumption, or physical activity. The odds for NAFLD increased in the range of 1.40-1.63 with 1 SD decrease in RHGS according to the strata.

CONCLUSIONS

This study of South Korean adults suggests that lower handgrip strength is associated with NAFLD regardless of sociodemographic characteristics, weight status, metabolic syndrome, concurrent illnesses, and lifestyle.

αMSH inhibits adipose inflammation via reducing FoxOs transcription and blocking Akt/JNK pathway in mice

Alpha melanocyte stimulating hormone (αMSH) abates inflammation in multiple tissues, while Forkhead box proteins O (FoxOs) stimulate inflammatory cascade. However, the relationship between αMSH and FoxOs in adipose inflammation remains unclear. In this study, we used LPS-induced inflammation model, attempted to interpret the function of αMSH in inflammation and the interactions with FoxOs. Results indicated that upon inflammatory situation, the secretion of αMSH and the expression of its receptor MC5R were greatly decreased, but FoxOs expressions were elevated. After the treatment with αMSH, LPS-induced adipose inflammation together with FoxOs expressions was significantly reduced. Conversely, when Foxo1, Foxo3a or Foxo4 overexpressed in αMSH treated inflammatory mouse model, all the anti-inflammatory impacts of αMSH were found disappeared. We further studied the mechanisms by which αMSH exerts its anti-inflammatory impacts and how FoxOs reverse αMSH's function. Foxo4 was found as a negative regulator for MC5R transcription in αMSH inhibited inflammation. Moreover, a negative role was found of αMSH in regulating both Akt and JNK signal pathways by observing the enhanced the anti-inflammatory impacts of pathway-specific inhibitors with αMSH treatment. Our findings demonstrate αMSH plays a key role in the prevention of adipose inflammation and inflammatory diseases by down-regulating Akt/JNK signal pathway and negatively interacting with FoxOs, which brings up αMSH as a novel candidate factor in the adipose anti-inflammation process in obesity.

Investigation of Blood Betatrophin Levels in Obese Children with Non-Alcoholic Fatty Liver Disease

PURPOSE

The prevalence of obesity has significantly increased among children and adolescents worldwide and is becoming an important health care problem in parallel with the increased prevalence of obesity pediatric non-alcoholic fatty liver disease. Betatrophin is a newly define hormone that is commonly secreted by liver and plays role in glucose tolerance. This study aimed to investigate the relationship between serum betatrophin levels and non-alcoholic fatty liver disease in obese children.

METHODS

The study included 40 obese children with a body mass index (BMI) above 95th centile, and 35 non-obese subjects with a BMI 3-85th centile, whose age and gender were similar to those of the patient group. For the evaluation of metabolic parameters fasting serum glucose, insulin, alanine aminotransferase, aspartate aminotransferase, lipid profile and serum betatrophin levels were measured. Total cholesterol: high-density lipoprotein cholesterol and low-density lipoprotein cholesterol: high-density lipoprotein cholesterol ratios were calculated as "atherogenic indices."

RESULTS

Serum betatrophin levels of the obese subjects were similar to that of non-obese subjects (p=0.90). Betatrophin levels were not correlated with the metabolic parameters.

CONCLUSION

In the present study, levels of betatrophin are not different between obese and insulin resistant children and non-obese subjects, and they are not correlated with atherogenic indices. To elucidate the exact role of betatrophin in obesity, further studies are required to identify the betatrophin receptor and/or other possible cofactors.

The Clinical Implications of Fatty Pancreas: A Concise Review

Fatty pancreas is a newly recognized condition which is poorly investigated until today as compared to nonalcoholic fatty liver disease. It is characterized by pancreatic fat accumulation and subsequent development of pancreatic and metabolic complications. Association of fatty pancreas have been described with type 2 diabetes mellitus, acute and chronic pancreatitis and even pancreatic carcinoma. In this review article, we provide an update on clinical implications, pathogenesis, diagnosis, treatment and outcomes.

C-C chemokine receptor type 5 deficiency exacerbates alcoholic fatty liver disease through pro-inflammatory cytokines and chemokines-induced hepatic inflammation

BACKGROUND AND AIM

Chemokines and chemokine receptors implicated with alcoholic liver disease. Studies have shown that inflammation and oxidative stress induce fat molecules aggregation in liver. We evaluated the relationship between alcoholic fatty liver disease and C-C chemokine receptor 5 (CCR5) and impact of inflammation and oxidative stress in fat molecule deposition.

METHODS

Lieber-DeCarli diet containing ethanol or isocaloric control diets were fed to wild-type and CCR5 knockout mice for 10 days and gavaged with a single dose of ethanol or isocaloric maltose dextrin at 11th day. Cytokine, chemokine, and reactive oxygen species levels were measured in liver tissues to study the role of CCR5 in alcoholic fatty liver disease.

RESULTS

C-C chemokine receptor type 5 knockout mice exacerbated ethanol-induced liver injury. Serum levels of aspartate aminotransferase and alanine aminotransferase were higher in CCR5 knockout mice than wild-type mice, and CCR5 knockout mice showed more severe lipid accumulation in liver tissue than wild-type mice after ethanol feeding. Increased expressions of pro-inflammatory cytokines TNF-α and IL-6 and chemokines CCL2, CCL3, CCL4, and CCL5 result in exacerbation of hepatitis in CCR5 knockout mice after ethanol feeding. Oxidative stress induced by reactive oxygen species was more severe in CCR5 knockout mice, and increasing level of fatty acid import and decreasing level of lipid degradation resulted in lipid accumulation in ethanol-fed CCR5 knockout mice.

CONCLUSION

Deficiency of CCR5 exacerbates alcoholic fatty liver disease by hepatic inflammation induced by pro-inflammatory cytokines and chemokines and oxidative stress.

Impact of Mediterranean diet on metabolic syndrome, cancer and longevity

Obesity symbolizes a major public health problem. Overweight and obesity are associated to the occurrence of the metabolic syndrome and to adipose tissue dysfunction. The adipose tissue is metabolically active and an endocrine organ, whose dysregulation causes a low-grade inflammatory state and ectopic fat depositions. The Mediterranean Diet represents a possible therapy for metabolic syndrome, preventing adiposopathy or "sick fat" formation.The Mediterranean Diet exerts protective effects in elderly subjects with and without baseline of chronic diseases. Recent studies have demonstrated a relationship between cancer and obesity. In the US, diet represents amount 30-35% of death causes related to cancer. Currently, the cancer is the second cause of death after cardiovascular diseases worldwide. Furthermore, populations living in the Mediterranean area have a decreased incidence of cancer compared with populations living in Northern Europe or the US, likely due to healthier dietary habits. The bioactive food components have a potential preventive action on cancer. The aims of this review are to evaluate the impact of Mediterranean Diet on onset, progression and regression of metabolic syndrome, cancer and on longevity.

Circulating betatrophin concentration is negatively correlated with insulin resistance in obese children and adolescents

AIM

The current study aimed to investigate the relationship between serum betatrophin levels and metabolic and anthropometric parameters in obese children.

METHOD

The study included 40 obese children with a body mass index (BMI) above 95th centile, and 35 non-obese subjects with a BMI 3-85th centile, whose age and gender were similar to those of the patient group. Fasting serum glucose, insulin, lipid profile, alanine aminotransferase, aspartate aminotransferase, serum betatrophin, and leptin levels were measured to evaluate the metabolic parameters. Total cholesterol:high-density lipoprotein cholesterol and low-density lipoprotein cholesterol:high-density lipoprotein cholesterol ratios were calculated as "atherogenic indices".

RESULTS

Serum betatrophin levels of the obese subjects were significantly lower than that of non-obese subjects (p<0.05). Insulin resistant subjects had significantly lower betatrophin concentrations than those of non-insulin resistant subjects (p<0.05). Betatrophin levels were negatively correlated with the fasting serum insulin and, accordingly insulin resistance index.

CONCLUSION

Serum betatrophin levels are lower in obese and insulin resistant subjects and betatrophin might act as a potential biomarker of insulin resistance in obese children or adolescents.

Characterisation of betatrophin concentrations in childhood and adolescent obesity and insulin resistance

BACKGROUND AND OBJECTIVE

Betatrophin, a novel hormone, is correlated with insulin resistance and promotes pancreatic β-cell growth in mice. The aim of this study was to determine circulating betatrophin levels in overweight or obese children and adolescents.

METHODS

The following pairs of subjects were included: (i) normal-weight healthy (n = 27) and overweight or obese (n = 28); (ii) non-insulin-resistant overweight or obese (n = 25) and insulin-resistant obese (n = 15); (iii) normal-weight males (n = 18) and females (n = 20); (4) 5 to 8 yr olds (n = 20) and 8 to 14 yr olds (n = 18). Circulating betatrophin levels were measured using enzyme-linked immunosorbent assay (ELISA). In addition, clinical data were recorded and anthropometrical measurements were performed.

RESULTS

Circulating betatrophin levels were increased significantly in obese children and adolescents with insulin resistance (365.77 ± 30.86 pg/mL) compared with overweight or obese subjects without insulin resistance (274.25 ± 26.52 pg/mL; p < 0.05). However, no differences in betatrophin levels were seen between lean and overweight or obese children (323.18 ± 25.91 vs. 348.27 ± 18.91 pg/mL, respectively; p > 0.05). In the normal-weight cohort, males had higher serum betatrophin level than did females, and subjects <8 yr old had lower serum betatrophin levels compared with those >8 yr. Surprisingly, betatrophin concentrations were correlated negatively with body mass index (BMI), but not with the BMI Z-score, in non-insulin-resistant children and adolescents.

CONCLUSIONS

These results demonstrated that circulating betatrophin levels were increased in insulin-resistant obese children or adolescents and might act as a potential biomarker of insulin resistance in these populations. Furthermore, serum betatrophin concentrations might vary during the development of children and adolescents, as well as between genders.

Muscle function and fat content in relation to sarcopenia, obesity and frailty of old age--An overview

BACKGROUND AND AIM

In western countries, the proportion of people over age 60 is increasing faster than any other group. This is linked to higher rates of obesity. Older age, co-morbidities and obesity are all associated with frailty syndrome. In the core of both frailty and sarcopenia there are dysfunction and deterioration of the muscle and the fat tissues. This overview interlinks the phenotypes presented in older adults such as sarcopenia and frailty-alone and with relation to obesity, muscle function and fat tissue accumulation.

RECENT FINDINGS

Observational studies have well described the loss of muscle mass and strength through the years of adult life, both components of frailty and sarcopenia. They have shown that these changes are associated with dysmetabolism and functional deterioration, independent of common explanatory variables. In the metabolic mechanism core of this link, insulin resistance and higher ectopic fat accumulation may play a role. Basic experiments have partially validated this hypothesis. Whether there is a synergistic effect of obesity and frailty phenotype on morbidity risk is still questionable and currently under investigation; however, few cohort studies have shown that the frail-obese or sarcopenic-obese group have higher probability for metabolic complications.

SUMMARY

Muscle mass loss and fat accumulation in the muscle in the elderly, with or without the presence of obesity, may explain some of the functional and metabolic defects shown in the frail, sarcopenic population.

Nonalcoholic fatty pancreas disease and Nonalcoholic fatty liver disease: more than ectopic fat

OBJECTIVE

The aim of this study was to evaluate the metabolic effects of fatty pancreas (nonalcoholic fatty pancreas disease - NAFPD) in a group of obese paediatric patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

We included 121 consecutive children with echographic evidence of hepatic steatosis. All patients underwent to abdominal ultrasound to evaluate pancreatic echogenic pattern. We divided the patients into two groups on the basis of the presence of fatty pancreas. In all patients liver function tests, lipid and gluco-insulinemic profile were evaluated. A selected subset of patients (67) underwent to liver biopsy.

RESULTS

Of these 121 patients, 58 showed NAFPD and 63 patients exhibited a normal pancreatic echogenic pattern. No differences were found in age, transaminases serum levels, lipid profile and pancreatic enzymes between the two groups. The patients with NAFPD had a significantly higher z-BMI, fasting insulin, insulin resistance (HOMA-IR) and lower ISI respect to the group without fatty pancreas. The patients with fatty pancreas showed a more advanced form of liver disease, with higher values of fibrosis, ballooning and NAS score with respect to the group without NAFPD.

CONCLUSIONS

Our study demonstrated that NAFPD is a frequent condition in obese paediatric patients affected by NAFLD. Our data suggest that pancreatic fat should not be considered an inert accumulation of fat, but as an additional factor able to affect glucose metabolism and severity of liver disease, increasing the risk of develop metabolic syndrome.

PPARα-Deficient ob/ob Obese Mice Become More Obese and Manifest Severe Hepatic Steatosis Due to Decreased Fatty Acid Oxidation

Obesity poses an increased risk of developing metabolic syndrome and closely associated nonalcoholic fatty liver disease, including liver cancer. Satiety hormone leptin-deficient (ob/ob) mice, considered paradigmatic of nutritional obesity, develop hepatic steatosis but are less prone to developing liver tumors. Sustained activation of peroxisome proliferator-activated receptor α (PPARα) in ob/ob mouse liver increases fatty acid oxidation (FAO), which contributes to attenuation of obesity but enhances liver cancer risk. To further evaluate the role of PPARα-regulated hepatic FAO and energy burning in the progression of fatty liver disease, we generated PPARα-deficient ob/ob (PPARα(Δ)ob/ob) mice. These mice become strikingly more obese compared to ob/ob littermates, with increased white and brown adipose tissue content and severe hepatic steatosis. Hepatic steatosis becomes more severe in fasted PPARα(Δ)ob/ob mice as they fail to up-regulate FAO systems. PPARα(Δ)ob/ob mice also do not respond to peroxisome proliferative and mitogenic effects of PPARα agonist Wy-14,643. Although PPARα(Δ)ob/ob mice are severely obese, there was no significant increase in liver tumor incidence, even when maintained on a diet containing Wy-14,643. We conclude that sustained PPARα activation-related increase in FAO in fatty livers of obese ob/ob mice increases liver cancer risk, whereas deletion of PPARα in ob/ob mice aggravates obesity and hepatic steatosis. However, it does not lead to liver tumor development because of reduction in FAO and energy burning.