Evaluation of leptin levels in subjects at risk for type 1 diabetes

The impact of transgenic papaya (TPY10-4) fruit supplementation on immune responses in ovalbumin-sensitised mice

BACKGROUND

A transgenic papaya line (TPY10-4) that is resistant to both papaya ringspot virus (PRSV) and papaya leaf distortion mosaic virus (PLDMV) has been developed in Taiwan. This study investigated the immunomodulatory properties of transgenic TPY10-4 and its native (TCK) papaya fruits using an ovalbumin (OVA)-sensitised mouse model. Both green and ripe papaya fruits at low (0.2 g powder kg(-1) body weight (BW)) and high (1.6 g powder kg(-1) BW) doses were administered to experimental mice by intragastric gavage for 5 weeks. Changes in serum total immunoglobulin A (IgA), IgE, IgG and IgM levels, OVA-specific IgE, IgG1 and IgG2a titres and Th1/Th2 cytokine secretions using splenocytes were determined.

RESULTS

Transgenic TPY10-4 or native TCK papaya fruit supplementation did not significantly affect body, visceral organ and relative tissue weights, total IgE antibody levels, OVA-specific IgE and IgG1 antibody titres or OVA-stimulated interferon-γ (IFN-γ), interleukin-2 (IL-2), IL-4, IL-5 and IL-10 secretions using splenocytes. However, transgenic papaya fruits markedly increased serum total IgM levels.

CONCLUSION

This study suggests that transgenic TPY10-4 papaya fruits do not increase the allergenic potential of OVA by oral administration but may have a protective immunity via increasing the serum total IgM level.

Non-alcoholic fatty liver disease: the new epidemic and the need for novel nutritional approaches

The epidemic of non-alcoholic fatty liver disease (NAFLD) in the United States is staggering, and there is an enormous void in our understanding of the clinical epidemiology other than the common themes of obesity and insulin resistance. There is also a public health need to better define effective treatments of NAFLD, including dietary interventions and appropriate nutritional supplements. There is, however, a wealth of basic science that helps to set the stage for defining the mechanisms leading to liver pathology. In this article we will attempt to put these concepts in perspective to highlight the need for future research including the use of medicinal food.

Systemic lupus erythematosus in the elderly

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, characterized by multisystemic involvement. Late onset SLE represents a specific sub-group of the disorder, beginning above 50-65 years of age. The incidence of late onset SLE ranges in the interval of 12-18% and the course of the disease is considered to be more benign. According to several authors, skin manifestations, photosensitivity, arthritis and nephritis, occur rarely in the elderly patients with late SLE onset; prevalence of serositis, lung involvement and Sjögren's syndrome were observed more often. Late onset SLE patients manifested higher rate of positive findings of rheumatoid factors, as well as of anti-Ro and anti-La antibodies; and the lower occurrence of anti-RNP antibodies and hypocomplementaemia. A slow onset of the disorder, non-specific manifestations at the beginning of the illness and less frequent prevalence of SLE in the elderly often result in late diagnosis. Treatment of the disease depends on its clinical manifestations. NSAID's, antimalarials or low doses of glucocorticoids are used for the less severe forms. Immunosuppressives and higher doses of glucocorticoids are the treatments of choice for more severe organ involvements and complications. A multidisciplinary approach is recommended for the treatment of late onset SLE patients.

Smoking cessation: significance and implications for children

A number of people in the USA who are still current smokers remain a staggering figure. Although this number continues to decrease, there is still a considerable amount of second-hand smoke. More importantly and for the purpose of this review, the detrimental effects of passive smoke in children is significant. We will not review the specific health effects of passive smoke, but for pediatricians, in particular, it is important to place in perspective programs that are available to influence the parents of children to stop smoking. Indeed, approximately 25% of all children aged 3-11 live in a household with at least one smoker. Despite the increasing number of communities in the states that have instituted restrictions or complete bans on smoking in the workplace and in many public areas, the principal site of smoking remains the home.

Leptin in autoimmunity: many questions, some answers

It has recently become apparent that several molecules involved in the control of metabolism also play an important function in the regulation of immune responses. Among those molecules, the adipocyte-derived cytokine leptin has been shown to significantly influence innate and adaptive immune responses both in normal and in pathological conditions. For example, levels of leptin are typically low in infection and high in autoimmunity, both systemically and at the site of inflammation. Moreover, in addition to its long-known effects on the promotion of T helper 1 immune responses and cell-mediated immunity, leptin has more recently been found capable to constrain proliferation of regulatory T cells. As such, leptin represents not only a link between metabolism and immune responses in general but also a pivotal modulator of the magnitude of selected mechanisms of peripheral immunity in relation to body fat mass. We review here the most recent advances on the role of leptin in the control of immune tolerance and critically discuss how strategies aimed at neutralizing the leptin axis could represent innovative tools for the therapy of autoimmune disorders.

Adiponectin and leptin: potential tools in the differential diagnosis of pediatric diabetes?

The incidence of type 1 and type 2 diabetes mellitus in the pediatric population has increased over the past decade. The practitioner is often faced with the challenge of differentiating between type 1 and type 2 diabetes at the time of initial diagnosis because of the overlap of clinical and laboratory characteristics between these two entities. Adipokines are proteins secreted by the adipose tissue. Leptin and adiponectin are two adipokines that have been extensively studied in vitro, in animal studies, and in human subjects with type 1 and type 2 diabetes. Leptin and adiponectin play a significant role in the regulation of lipid and carbohydrate metabolism. Adiponectin increases insulin sensitivity in both the liver and skeletal muscle. Leptin decreases appetite, increases energy expenditure, suppresses insulin synthesis and secretion and increases insulin sensitivity. Changes in the secretion or sensitivity to leptin and adiponectin may contribute to the development of type 1 and type 2 diabetes. Adiponectin is higher in adult and pediatric patients with type 1 diabetes compared to those with type 2 diabetes. Data regarding leptin levels are contradictory. Most studies report decreased serum leptin at the time of diagnosis in type 1 diabetes compared to type 2 diabetes subjects and non-diabetic controls. This paper will review basic research and clinical evidence supporting the role of adiponectin and leptin in the development of type 1 and type 2 diabetes and discuss their potential use as tools in the differential diagnosis of pediatric diabetes.