The macrophage migration inhibitory factor protein superfamily in obesity and wound repair

The rising number of obese individuals has become a major burden to the healthcare systems worldwide. Obesity includes not only the increase of adipose tissue mass but importantly also the altered cellular functions that collectively lead to a chronic state of adipose tissue inflammation, insulin resistance and impaired wound healing. Adipose tissue undergoing chronic inflammation shows altered cytokine expression and an accumulation of adipose tissue macrophages (ATM). The macrophage migration inhibitory factor (MIF) superfamily consists of MIF and the recently identified homolog D-dopachrome tautomerase (D-DT or MIF-2). MIF and D-DT, which both bind to the CD74/CD44 receptor complex, are differentially expressed in adipose tissue and have distinct roles in adipogenesis. MIF positively correlates with obesity as well as insulin resistance and contributes to adipose tissue inflammation by modulating ATM functions. D-DT, however, is negatively correlated with obesity and reverses glucose intolerance. In this review, their respective roles in adipose tissue homeostasis, adipose tissue inflammation, insulin resistance and impaired wound healing will be reviewed.

The macrophage migration inhibitory factor protein superfamily in obesity and wound repair

The rising number of obese individuals has become a major burden to the healthcare systems worldwide. Obesity includes not only the increase of adipose tissue mass but importantly also the altered cellular functions that collectively lead to a chronic state of adipose tissue inflammation, insulin resistance and impaired wound healing. Adipose tissue undergoing chronic inflammation shows altered cytokine expression and an accumulation of adipose tissue macrophages (ATM). The macrophage migration inhibitory factor (MIF) superfamily consists of MIF and the recently identified homolog D-dopachrome tautomerase (D-DT or MIF-2). MIF and D-DT, which both bind to the CD74/CD44 receptor complex, are differentially expressed in adipose tissue and have distinct roles in adipogenesis. MIF positively correlates with obesity as well as insulin resistance and contributes to adipose tissue inflammation by modulating ATM functions. D-DT, however, is negatively correlated with obesity and reverses glucose intolerance. In this review, their respective roles in adipose tissue homeostasis, adipose tissue inflammation, insulin resistance and impaired wound healing will be reviewed.

Derivação gástrica em Y-de-Roux e a atividade inflamatória do tecido adiposo / Roux-en-Y gastric bypass and inflammatory activity of the adipose tissue

OBJETIVO: Avaliar os indicadores de estresse oxidativo e marcadores inflamatórios em obesos antes e depois da gastroplastia vertical com bandagem em Y-de-Roux. MÉTODOS: Vinte obesos classe III foram submetidos à gastroplastia vertical com bandagem em Y-de-Roux, sendo sete homens e 13 mulheres, com idade média de 39 anos e 20 indivíduos não obesos, nove homens e 11 mulheres, média de idade de 38 anos. Foram determinados os níveis de malondialdeído no plasma, índice de estresse, capacidade antioxidante total, catalase e glutationa reduzida e oxidada, e marcadores inflamatórios (proteína C reativa e á-1 glicoproteína ácida). No grupo obeso, estes parâmetros foram determinados antes e 2, 6 e 12 meses após a gastroplastia vertical com bandagem em Y-de-Roux. RESULTADOS: No pré-operatório, o grupo obeso apresentou níveis elevados de marcadores inflamatórios, de estresse oxidativo (níveis de malondialdeído e índice de estresse) e menores níveis de indicadores de defesa antioxidante em relação ao grupo controle. O emagrecimento foi acompanhado de redução progressiva do níveis de malondialdeído e do índice de estresse. Foi observado aumento da concentração de glutationa reduzida e da capacidade antioxidante total e redução dos níveis de marcadores inflamatórios. CONCLUSÃO: A redução do peso melhora o estado inflamatório e os níveis de estresse oxidativo.

OBJECTIVE: To evaluate the oxidative stress and inflammatory markers in obese patients before and after Roux-en-Y vertical banded gastroplasty. METHODS: We studied 20 class III obese patients undergoing Roux-en-Y vertical banded gastroplasty, seven men and 13 women, mean age 39 years, and 20 non-obese subjects, nine males and 11 females, mean age 38 years. We determined the plasma levels of malondialdehyde, stress an index, total antioxidant capacity, catalase, reduced and oxidized glutathione and inflammatory markers (C reactive protein and á-1 acid glycoprotein). In the obese group, these parameters were determined before and 2, 6 and 12 months after gastroplasty. RESULTS: Preoperatively, the obese group showed elevated levels of inflammatory markers of oxidative stress (malondialdehyde levels and stress index) and lower levels of indicators of antioxidant defense compared to the control group. Weight loss was accompanied by gradual reduction in the levels of malondialdehyde and stress index. We found an increased concentration of reduced glutathione and total antioxidant status and reduced levels of inflammatory markers. CONCLUSION: Weight loss improves the inflammatory state and oxidative stress levels.

relation between asthma, body fat distribution and serum adiponectin in obese Egyptian children

Childhood obesity is an emerging global public health challenge. That is because the prevalence of obesity among children and adolescents has increased greatly in all parts of the world. A number of studies have reported an inverse relation between respiratory function and various indices of obesity or fat distribution [El-Baz et al., 2009]. Adiponectin, an antiinflammatory adipocytokine, circulates at lower levels in the obese, which is thought to contribute to obesity-related inflammatory disease as bronchial asthma [Medoff et al., 2009]. The aim of this work was to assess the correlation between the bronchial asthma, obesity, fat distribution and serum adiponectin in obese Egyptian children. The present study included a group of obese fifty [50] children [25 boys and 25 girls] without the co morbidities of the metabolic syndrome; aged 7-18 years, mean age [14.2 +/- 3.9]. Obesity without the co morbidities of the metabolic syndrome was defined as a BMI above the 85th percentiles according to BMI Charts of Egyptian Growth Charts for boys and girls from 2-21 years [2002]. They were compared to thirty [30] lean sex and age matched controls mean age [14.1 +/- 4.8] [15 boys and 15 girls] with BMI between the 10[th] and 75[th] percentile. Anthropometric measurements [body weight, BMI, WC and fat mass% by DEXA] were done for all children together with pulmonary function test and assessment of serum adiponectin levels. Weight, Waist circumference [WC], Body mass index [BMI], fat mass% and adiponectin were significant higher in obese compared to non obese groups [p<0.001 for all]. Parameters of pulmonary function was significant lower in obese compared to non obese groups as regard forced vital capacity [FVC], forced expiratory volume in one second [FEV1], peak expiratory flow maximum [PEF] and forced midexpiratory flow 25%[FEF25%] [p<0.01 for all]. while no significant difference was found between both groups as regard FEV1/FVC ratio and forced midexpiratory flow rate[FEF25-75%][p>0.05 for both]. A negative association of BMI with parameters of pulmonary function was found but only FEV1, FVC and FEF 25% were statistically significant [p<0.01 for all]. As regard WC it was negatively correlated with FEV1, FVC and FEF 25% [p<0.01 for all] but no correlation was found with other parameters of pulmonary functions [p>0.05]. In the present study a negative correlation was found between fat mass% and parameters of pulmonary function but none of them was statistically significant [p>0.05 for all]. A negative significant correlation was found between adiponectin and age in obese group [p>0.05] .As regard anthropometric parameters in obese group a significant negative correlation was found between adiponectin and BMI, WC and fat mass% [p<0.01 for all] while no correlation was found with body weight [p>0.05]. As regard of pulmonary function parameters a negative significant correlation was found between serum adiponectin and FVC and PEF% [p<0.01 for both] while a negative correlation was found between adiponectin and FEF 25% but this correlation was statistically insignificant [p>0.05], While no correlation was found with FEV1/FVC ratio [p>0.05]. The increasing prevalence of overweight and obesity among Egyptian children may be an important contributor to the increasing incidence and prevalence of asthma. Adiponectin may be one of the signals linking obesity with asthma

Impact of adiposity on immunological parameters / Impacto da adiposidade nos parâmetros imunológicos

Studies evaluating immune function in obese humans and experimental animals indicate that the excess adiposity is associated with impaired in immune responses. Obesity is related to a higher rate of infections and to some types of cancer. Nutritional, metabolic and endocrine factors are implicated in the immunological changes. The adipose tissue directly produces substances with various functions related to immune system. Furthermore, some investigations suggest that certain types of weight reduction strategies can alter the immune function. Nevertheless, long-term studies should be carried out to address whether these changes positively affects the ability of these obese individuals to control infections and tumor development.

Estudos acerca da função imunológica em animais experimentais e humanos obesos indicam que o excesso de adiposidade associa-se ao prejuízo da resposta imune. A obesidade está relacionada a uma taxa maior de infecções e a alguns tipos de câncer. Fatores nutricionais, metabólicos e endócrinos estão implicados nessas alterações imunológicas. O próprio tecido adiposo produz diretamente substâncias com várias funções relacionadas ao sistema imune. Além disso, algumas investigações sugerem que certas estratégias para perda de peso podem alterar a função imune. Entretanto, estudos em longo prazo são necessários para avaliar se tais alterações afetam positivamente a capacidade desses pacientes obesos de controlar infecções e desenvolver tumores.

Adipocinas, tejido adiposo y su relación con células del sistema inmune / Adipocytokines, adipose tissue and its relationship with immune system cells

Adipocinas o adipocitocinas son los términos para referirse a las proteínas secretadas por el tejido adiposo. Entre ellas destacan la pro teína estimuladora de acilación (ASP), TNF-a, IL-6, la resistina, la leptina y la adiponectina, con influencia sobre la sensibilidad a la insulina, así como el angiotensinógeno y el inhibidor del activador de plasminógeno (PAI-1) que tienen efecto sobre la vascularización. Diversos estudios indican que existe relación entre los adipocitos y las células del sistema inmune, consecuencia de un mecanismo de supervivencia y adaptación metabólica bajo condiciones adversas. Ahora se sabe que las adipocinas contribuyen a la inflamación y la resistencia a la insulina que presenta el sujeto obeso. Estas adaptaciones, conjuntamente con el estrés y el confort de la vida moderna, han contribuido al deterioro del organismo y han desencadenado la inflamación originada en el tejido adiposo. El objetivo de esta revisión es analizar la información que ha llevado al descubrimiento y esclarecimiento de la fisiología del tejido adiposo en relación con la secreción de diversas proteínas y de la inflamación originada en el mismo. En este sentido, las terapias dirigidas al tratamiento de las enfermedades relacionadas con la obesidad deberán orientarse a modificar el proceso inflamatorio originado en el tejido adiposo.

A dipokines or adipocytokines are the proteins secreted by the adipose tissue. These bioactive molecules include proteins that modify insulin sensitivity (acylation stimulating protein (ASP), TNF-a, IL- 6, resistin, leptin and adiponectin), and proteins that have known effects on vascularity (angiotensinogen and the plasminogen inhibitor protein PAI-1). Several studies have found a close relationship between adipocytes and immune cells as a consequence of evolutionary mechanisms that favor metabolic adaptation and survival under adverse conditions. It is known that adipokines contribute to the inflammation and insulin resistance present in obese individuals. The aim of this review is to analyze current information related to the physiology of the adipose tissue, with a special emphasis on the secretion of adipokines and their role in inflammation. We recommend that therapies addressing the treatment of obesity related disorders should focus on modifying the inflammatory process that originates in the adipose tissue.