Carotenoids (Car), β-Carotene (I), 8′-apo-β-caroten-8′-al (II), and canthaxanthin (III), incorporated into activated Cu-MCM-41 were examined by UV/vis and EPR spectroscopies. A Cu 2+ -Car complex was formed for I and III but not for II. Formation of a complex results in distortion of the all-trans carotenoid geometry and a tetragonal geometry for Cu 2+ . The binding energies of Car and Cu 2+ , the changes in the maximum absorption, and the bond lengths of Car after the formation of the Cu 2+ -Car complex were examined by semiempirical ZINDO/1 and ZINDO/S calculations. Formation of a complex between Car and Cu 2+ favors both forward and back electron transfer (ET) reactions due to the short distance (∼2 Å) between Car and Cu 2+ , and reversible ET appears upon temperature cycling.

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Objective-To study the effects of a short-term very-low calorie diet (VLCD) on intramyocellular lipid (IMCL), total body fat, and insulin sensitivity in a group of obese non-diabetic and Type 2 Diabetic (T2DM) patients.Research Methods and Procedures-Seven untreated T2DM and 5 obese non-diabetic individuals were studied before and after a 6-day VLCD using proton-magnetic resonance spectroscopy to quantify IMCL, DXA to assess body fat, and hyperinsulinemic-euglycemic clamps to measure peripheral insulin sensitivity.Results-In both groups, decrements in total body fat mass and BMI were small but statistically significant. In contrast, the diet resulted in a pronounced reduction in IMCL compared to baseline values in non-diabetics (56% decrease) and T2DM (40% decrease), P<0.05, and this was accompanied by an overall 9.3% increase in maximally-stimulated glucose disposal rate (P<0.01). IMCL was significantly correlated with insulin sensitivity, (r=−0.69; P<0.01) and waist circumference (r = 0.72 and 0.83, baseline and post-diet respectively, both P < 0.01), but neither IMCL nor insulin sensitivity was related to measures of general adiposity such as BMI, % body fat, or total body fat (P=NS).Conclusions-Short-term VLCD is accompanied by small decrements in general adiposity, marked decrease in IMCL, and an increase in insulin sensitivity in non-diabetic and T2DM subjects. Therefore, rapid amelioration of insulin resistance by VLCD can be partially explained by loss of IMCL in both non-diabetics and in T2DM in the absence of substantial changes in total body fat. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. NIH Public Access Author ManuscriptMetabolism. Author manuscript; available in PMC 2009 January 1. Published in final edited form as:Metabolism. 2008 January ; 57(1): 1-8. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author ManuscriptThese observations are consistent with the idea that insulin resistance is more directly related to IMCL rather than body fat per se.

Weight restoration is an important first step in treating patients with anorexia nervosa (AN), because it is essential for medical stabilization and reversal of long-term complications. Tube feeding may help facilitate weight restoration, but its role in treatment remains unclear. This study aimed to review the literature describing the efficacy, safety, tolerance, and long-term effects of nasogastric (NG) refeeding for patients with AN. Four electronic databases were systematically searched through May 2018. Boolean search terms included "anorexia nervosa," "refeeding," and "nasogastric tube feeding." Ten studies were eligible for inclusion: 8 retrospective chart reviews, 1 prospective cohort, and 1 randomized controlled trial. Nine of the studies were performed in-hospital. In 8 studies, NG nutrition resulted in an average rate of weight gain exceeding 1 kg/wk. In 4 of 5 studies including an oral-only control group, mean weekly weight gain and caloric intake were significantly higher in tube-fed patients. Six studies provided prophylactic phosphate supplementation, all with <1% occurrence rate of refeeding hypophosphatemia. Seven studies reported on other physiological disturbances, 6 evaluated medical and gastrointestinal side effects, 3 considered psychological outcomes, and 4 assessed patients postdischarge. Results indicated that NG feeding was not associated with an increased risk for adverse outcomes. Overall, in these studies, NG nutrition was considered safe and well tolerated, and effectively increased caloric intake and rate of weight gain in patients with AN. However, results are limited by weaknesses in study designs, and more rigorous methods are needed for development of evidence-based, standardized refeeding protocols.