Interferon-gamma carrying nanoemulsion with immunomodulatory and anti-tumor activities.

The therapeutic administration of cytokines has been introduced aiming to modulate the immune response system, seeking for different approaches to face pathologies such as cancer, auto immune and infectious diseases. The objective of this study was to investigate the effects of a stable oil-in-water (O/W) nanoemulsion system carrying the cytokine Interferon gamma (IFN-γ) on the activity of phagocytes and MCF-7 human breast cancer cells. Nanoemulsions were prepared through ultra-homogenization, and they consisted of distilled water, triglycerides of capric acid/caprylic, sorbitan-oleate, polysorbate 80, and 1-butanol. IFN-γ (100 ng ml-1 ) was incorporated into two O/W nanoemulsion formulations, and these formulations were characterized in terms of their preliminary and accelerated physicochemical stability, rheological properties, droplet size, polydispersity and surface charge. We identified the most optimal IFN-γ nanoemulsion (IFN-γNE2), which remained stable under extreme temperature variations for 90 days, contained an average dose of 97 ng ml-1 of IFN-γ and exhibited a biocompatible pH and a relative stable rheological profile. Cell viability and intracellular Ca2+ release assays conducted showed that IFN-γNE2 reduced the cell viability of MCF-7 cells without affecting the cell viability of phagocytes. Furthermore, IFN-γNE2 was able to induce cellular activity of phagocytes as evidenced by increased intracellular Ca2+ release in these cells. Our findings on this IFN-γ nanoemulsion suggest that it can be a promising therapeutic agent for immunostimulation and cancer treatment.

O-Glycosylation with O-linked ß-N-acetylglucosamine increases vascular contraction: Possible modulatory role on Interleukin-10 signaling pathway.

AIMS: The interleukin-10 (IL-10) is an immuno-regulatory cytokine that plays a protective effect in the vasculature. IL-10 binding to its receptor, activating the IL-10/JAK1/STAT3 cascade to exert its effects. Therefore, STAT3 phosphorylation is essential for IL-10 actions. O-Glycosylation with linked ß-N-acetylglucosamine (O-GlcNAc) is a post-translational modification able to regulate many proteins by interfering with protein on a phosphorylation level. Our aim was to determine whether O-GlcNAc promotes the inhibition of IL-10-pathway (JAK1/STAT3/IL-10), inactivationg its action in the vasculature. MAIN METHODS: Mice (C57BL/6) aortic segments were incubated with vehicle or Thiamet G (0.1 mM, for 24 h) to increase global O-GlcNAc levels. Aortas from knockout mice for IL-10 were also used. Vascular reactivity and western blot tests were performed to evaluate protein expression. KEY FINDINGS: High levels of O-GlcNAc, induced by Thiamet G incubation, increased vascular expression of JAK1, but decreased expression and activity of STAT3. In addition, IL-10 levels were diminished in arteries treated with Thiamet G. Absence of IL-10, as well as augmented O-GlcNAcylation, increased vascular reactivity to constrictor stimuli, an effect that was abolished by ERK 1/2 inhibitor. High levels of O-GlcNAc and the absence of IL-10 also leads to increased vascular expression of ERK1/2. SIGNIFICANCE: Our data suggest that O-GlcNAc modification seems to (dys)regulate IL-10 signaling pathway and consequently, compromise the protective effect of this cytokine in vasculature. It is possible that there is a promising relationship in pathophysiological conditions where changes in O-GlcNAcylation and IL-10 levels are observed, such as hypertension and diabetes.

Relationship between Proinflammatory Cytokines/Chemokines and Adipokines in Serum of Young Adults with Obesity.

BACKGROUND AND OBJECTIVE: The adipose tissue has been recognized as an important endocrine organ, which is metabolically active and expresses and secretes various inflammatory cytokines. Inflammation is involved in obesity-related complications. As such, the present study investigated the correlation between biochemical parameters, serum proinflammatory cytokines and adipokines in individuals with obesity. METHODS: Based on the body mass index (BMI), 30 subjects were divided into 3 groups: eutrophic (GC, n = 10), overweight (GOW, n = 10) and obese (GOB, n = 10). Serum glucose, cholesterol (total-C, HDLC and LDL-C), triglycerides, total proteins, uric acid and insulin were determined, as well as cytokines IL-8, TNF-α, IL-1ß, and IL-6, leptin and adiponectin. RESULTS: GOB showed the highest glucose, total and LDL-C, triglycerides, uric acid, insulin, leptin, IL- 8, IL-1ß, IL-6, TNF-α and lowest adiponectin levels. In general, adiponectin exhibited an inverse correlation with BMI, abdominal circumference, LDL-C, IL-6, TNF-α, leptin and leptin-adiponectin ratio (LAR) and a positive correlation with HDL-C. Leptin was positively correlated with BMI, abdominal circumference, insulin, IL-6, TNF-α and LAR and negatively correlated with HDL-C and adiponectin. The LAR was positively correlated with BMI, waist circumference, insulin, TNF-α and negatively associated with HDL-C. CONCLUSION: The results confirm that obesity changes the lipid and glycemic profiles of individuals, increases the proinflammatory adipokine levels and reduces those of anti-inflammatory adipokines, promoting a state of chronic inflammation.