Prevalence of obesity has steadily increased over the past three decades both in the United States and worldwide. Recent studies have shown the role of dietary polyphenols in the prevention of obesity and obesity-related chronic diseases. Here we evaluated the impact of commonly consumed polyphenols, including green tea catechins and epigallocatechin gallates, resveratrol, and curcumin, on obesity and obesity-related-inflammation. Cellular studies demonstrated that these dietary polyphenols reduce viability of adipocytes and proliferation of preadipocytes, suppress adipocyte differentiation and triglyceride accumulation, stimulate lipolysis and fatty acid β-oxidation, and reduce inflammation. Concomitantly, the polyphenols modulate signaling pathways including the AMP-activated protein kinase, peroxisome proliferator activated receptor γ, CCAAT/enhancer binding protein α, PPAR gamma activator 1-alpha, sirtuin 1, sterol regulatory element binding protein-1c, uncoupling proteins 1 and 2, and nuclear factor kappa B that regulate adipogenesis, antioxidant and anti-inflammatory responses. Animal studies strongly suggest that commonly consumed polyphenols described in this review have a pronounced effect on obesity as shown by lower body weight, fat mass, and triglycerides through enhancing energy expenditure and fat utilization, and modulating glucose hemostasis. Limited human studies have been conducted in this area, and are inconsistent about the anti-obesity impact of dietary polyphenols, probably due to the various study designs and lengths, variation among subjects (age, gender, ethnicity), chemical forms of the dietary polyphenols used and confounding factors such as other weight reducing agents. Future randomized controlled trials are warranted to reconcile the discrepancies between preclinical efficacies and inconclusive clinic outcomes of these polyphenols.

We demonstrate that uniform dispersion of TiO(2) on graphene is critical for the photocatalytic effect of the composite. The hydrothermal method was employed to synthesize TiO(2) nanowires (NW) and then fabricate graphene-TiO(2) nanowire nanocomposite (GNW). Graphene oxide (GO) reduction to graphene and hybridization between TiO(2) NWs and graphene by forming chemical bonding was achieved in a one-step hydrothermal process. Graphene-TiO(2) nanoparticle (NP) nanocomposite (GNP) was also synthesized. Photocatalytic performance and related properties of NP, NW, GNP, and GNW were comparatively studied. It was found that by incorporation of graphene, GNP and GNW have higher performance than their counterparts. More importantly, it was found that NWs, in comparison with NPs, have more uniform dispersion on graphene with less agglomeration, resulting in more direct contact between TiO(2) and graphene, and hence further improved electron-hole pairs (EHPs) separation and transportation. The adsorbability of GNW is also found to be higher than GNP. The result reveals that the relative photocatalytic activity of GNW is much higher than GNP and pure NWs or NPs.

Nanotechnology is an innovative approach that has potential applications in nutraceutical research. Phytochemicals have promising potential for maintaining and promoting health, as well as preventing and potentially treating some diseases. However, the generally low solubility, stability, bioavailability and target specificity, together with the side-effects seen when used at high levels, have limited their application. Indeed, nanoparticles can increase solubility and stability of phytochemicals, enhance their absorption, protect them from premature degradation in the body, and prolong their circulation time. Moreover, these nanoparticles exhibit high differential uptake efficiency in the target cells (or tissue) over normal cells (or tissue)through preventing them from prematurely interacting with the biological environment, enhanced permeation and retention effect in disease tissues, and improving their cellular uptake, resulting in decreased toxicity, In this review we outline the commonly used biocompatible and biodegradable nanoparticles including liposomes, emulsions, solid lipid nanoparticles, nanostructured lipid carriers, micelles and poly (lactic-co-glycolic acid) (PLGA) nanoparticles. We then summarize studies that have used these nanoparticles as carriers for EGCG, quercetin, resveratrol and curcuminadministration to enhance their aqueous solubility, stability, bioavailability, target specificity, and bioactivities.

Nanocrystalline SnO 2 particles have been synthesized by a simple sol-gel method. The structural and optical properties of these SnO 2 particles are investigated using X-ray powder diffraction, transmission electron microscopy, UV-visible absorption, and photoluminescence spectroscopy. The oxygen-vacancies-related photoluminescence of pure, cerium-, and manganese-doped SnO 2 nanoparticles was systematically investigated. The origin of the luminescence is assigned to the recombination of electrons in a conduction band with holes in the V o •• center. Experimental results reveal that increasing calcining temperature can decrease the oxygenvacancies-related luminescence intensity of the sample. After introducing Ce 3+ /Mn 2+ ions into the host, the oxygen-vacancies-related luminescence has been enhanced remarkably resulting from the formation of many more oxygen vacancies. The dependence of the oxygen-vacancies-related luminescence intensity on the Ce 3+ / Mn 2+ concentration is also discussed.

Strategies to reduce obesity have become public health priorities as the prevalence of obesity has risen in the United States and around the world. While the anti-inflammatory and hypotriglyceridemic properties of long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) are well known, their antiobesity effects and efficacy against metabolic syndrome, especially in humans, are still under debate. In animal models, evidence consistently suggests a role for n-3 PUFAs in reducing fat mass, particularly in the retroperitoneal and epididymal regions. In humans, however, published research suggests that though n-3 PUFAs may not aid weight loss, they may attenuate further weight gain and could be useful in the diet or as a supplement to help maintain weight loss. Proposed mechanisms by which n-3 PUFAs may work to improve body composition and counteract obesity-related metabolic changes include modulating lipid metabolism; regulating adipokines, such as adiponectin and leptin; alleviating adipose tissue inflammation; promoting adipogenesis and altering epigenetic mechanisms.