Effect Of Short-term Dietary Restriction Research Articles

Effects of short-term dietary restriction on plasma metabolites and the subcutaneous fat area according to metabolic status in obese individuals: a case\u2013control study

BackgroundResearch elucidating the metabolic mechanisms that differentiate subtypes of obesity has been increasing. We aimed to investigate the effects of a 12-week dietary intervention on the metabolomic profiles of obese subjects.MethodsSubjects followed a 12-week dietary restriction protocol consisting of a 300 kcal/day reduction in their usual caloric intake. Twenty-nine obese subjects were included and divided into two groups: the metabolic status maintenance group (n = 17, controls) and the metabolic status improvement group (n = 12, tests). We analyzed the somatometric and biochemical parameters and performed ultra-performance liquid chromatography-mass spectrometry analysis of the plasma metabolites.ResultsAt 12 weeks, the fat percentage, whole fat area (WFA), subcutaneous fat area (SFA) at the L1 vertebra, and the levels of triglycerides, gamma-glutamyltransferase (gamma-GT), and leptin were markedly decreased in the metabolic status improvement group, while the level of high-density lipoprotein cholesterol increased compared with that in the metabolic status maintenance group. Metabolomic profiling at 12 weeks showed substantial differences in 4-aminobutyraldehyde (p = 0.005) and 4’-apo-β-carotenal (p = 0.024) between the two groups. Furthermore, an AUC value of 0.89 was obtained for the following seven featured biomarkers: triglycerides, gamma-GT, leptin, fat percentage, WFA, and SFA at the L1 vertebra, and 4-aminobutyraldehyde.ConclusionsWe demonstrated that 4-aminobutyraldehyde and related regional fat distribution parameters were strongly associated with obesity according to metabolic status. Thus, these biomarkers are potentially valuable in confirming the efficacy of short-term interventions and predicting metabolic status in obese individuals.Trials registration: This study was registered at ClinicalTrials.gov under NCT03135132 (registered 1 May 2017—retrospectively registered).

Short-term dietary restriction ameliorates brain injury after cardiac arrest by modulation of mitochondrial biogenesis and energy metabolism in rats.

BackgroundDietary restriction (DR) is a well-known intervention that increases lifespan and resistance to multiple forms of acute stress, including ischemia reperfusion injury. However, the effect of DR on neurological injury after cardiac arrest (CA) remains unknown.MethodsThe effect of short-term DR (one week of 70% reduced daily diet) on neurological injury was investigated in rats using an asphyxial CA model. The survival curve was obtained using Kaplan-Meier survival analysis. Serum S-100β levels were detected by enzyme linked immunosorbent assay. Cellular apoptosis and neuronal damage were assessed by terminal deoxyribonucleotide transferase dUTP nick end labeling assay and Nissl staining. The oxidative stress was evaluated by immunohistochemical staining of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Mitochondrial biogenesis was examined by electron microscopy and mitochondrial DNA copy number determination. The protein expression was detected by western blot. The reactive oxygen species (ROS) and metabolite levels were measured by corresponding test kits.ResultsShort-term DR significantly improved 3-day survival, neurologic deficit scores (NDS) and decreased serum S-100β levels after CA. Short-term DR also significantly attenuated cellular apoptosis, neuronal damage and oxidative stress in the brain after CA. In addition, short-term DR increased mitochondrial biogenesis as well as brain PGC-1α and SIRT1 protein expression after CA. Moreover, short-term DR increased adenosine triphosphate, β-hydroxybutyrate, acetyl-CoA levels and nicotinamide adenine dinucleotide (NAD+)/reduced form of NAD+ (NADH) ratios as well as decreased serum lactate levels.ConclusionsReduction of oxidative stress, upregulation of mitochondrial biogenesis and increase of ketone body metabolism may play a crucial role in preserving neuronal function after CA under short-term DR.

Effects of short-term dietary restriction and glutamine supplementation in vitro on the modulation of inflammatory properties.

Dietary restriction (DR) is a nutritional intervention that exerts profound effects on biochemical and immunologic parameters, modulating some inflammatory properties. Glutamine (GLN) is a conditionally essential amino acid that can modulate inflammatory properties. However, there is a lack of data evaluating the effects of DR and GLN supplementation, especially in relation to inflammatory cytokine production and the expression of transcription factors such as nuclear factor (NF)-κB. We subjected 3-mo-old male Balb/c mice to DR by reducing their food intake by 30%. DR animals lost weight and showed reduced levels of serum triacylglycerols, glucose, cholesterol, and calcium as well as a reduction in bone density. Additionally, blood, peritoneal, and spleen cellularity were reduced, lowering the number of peritoneal F4/80- and CD86-positive cells and the total number of splenic CD4- and CD8-positive cells. The production of interleukin (IL)-10 and the expression of NF-κB in splenic cells were not affected by DR or by GLN supplementation. However, peritoneal macrophages from DR animals showed reduced IL-12 and tumor necrosis factor-α production and increased IL-10 production with reduced phosphorylation of NF-κB expression. Additionally, GLN was able to modulate cytokine production by peritoneal cells from the control group, although no effects were observed in cells from the DR group. DR induces biochemical and immunologic changes, in particular by reducing IL-12 and tumor necrosis factor-α production by macrophages and clearly upregulating IL-10 production, whereas GLN supplementation did not modify these parameters in cells from DR animals.

Effect of chronic unpredictable stress on short term dietary restriction and its modulation by multivitamin-mineral supplementation

Dietary restriction (DR) lowers steady-state levels of oxidative stress and alters behavioral, physiological and biochemical responses in mammals. However, various factors effect its application in humans like socio-cultural, appetite and the daily life stress. Physiological and psychological stress owing to fast-paced lifestyles, translates into oxidative stress. In this work, the role of chronic unpredictable stress (CUS) on the effects of short term DR in mice in terms of biochemical and oxidative stress parameters was investigated. Further, the modulatory role of multivitamin-mineral supplement (MVM) on CUS and DR induced biochemical changes was studied to delineate the role of micronutrient supplementation. DR treatment increased the antioxidant status in the circulation and liver of mice but in the presence of chronic stressors there was a significant shift towards the pro-oxidant state. A decrease was found in the activities of antioxidant enzymes superoxide dismutase, catalase, and glutathione-S-transferase and glutathione reductase in the rats exposed to CUS with DR (CUS+DR), with an increased malondialdehyde and a decreased glutathione (GSH) levels as compared to the controls. Liver function enzymes–glutamate oxaloacetate transaminase and glutamate pyruvate transaminase were increased and a significant DNA damage was observed. Oral MVM supplement significantly improved this oxidative deterioration. Hence, MVM supplementation appears to potentially offer an effective intervention in the DR regimen to combat daily life physical and mental stress.

Dietary Restriction Modifies Certain Aspects of the Postoperative Acute Phase Response

Lifespan extension is achieved through long-term application of dietary restriction (DR), and benefits of short-term dietary restriction on acute stress and inflammation have been observed. So far, the effects of short-term DR in humans are relatively unknown. We hypothesized that short-term DR in humans reduces the acute phase response following a well defined surgical trauma. Thirty live kidney donors were randomized between 30% preoperative dietary restriction followed by 1 d of fasting (n=17) or a 4 d ad libitum regimen (n=13) prior to surgery. Leukocyte subsets and numbers and serum cytokine levels were determined. Whole blood was stimulated with lipopolysaccharide (LPS) and cytokine production was determined. A clear trend towards lower numbers of postoperative circulating leukocytes was observed in the DR group. IL-8 serum levels were significantly higher in the DR group over the first 6 postoperative d (P=0.018). After LPS stimulation, significantly less TNF-α (P=0.001) was produced by blood obtained postoperatively compared with preoperative blood from the DR group. This was not observed in the control group. A relatively short preoperative dietary restriction regimen was able to modify certain aspects of the postoperative acute phase response. These data warrant further studies into the dietary conditions that improve stress resistance in humans. (Dutch Trial Registry number: NTR1875).

Adipose Gene Expression Response of Lean and Obese Mice to Short-term Dietary Restriction*

Overweight and obesity lead to higher morbidity risks, which are alleviated even by mild weight loss. To gain insight in the molecular effects of weight loss in adipose tissue, we analyzed the effects of short-term dietary restriction (DR) on mice fed a low-fat diet (lean mice) or a high-fat diet (obese mice). Female C57Bl6/J mice on both diets were on DR until an average body weight loss of 20%, which was achieved in 8 to 12 days depending on body weight at the start of DR. Plasma free fatty acids and blood glucose levels decreased significantly on DR. In the (restricted) low-fat diet groups, gene expression analysis using adipose-enriched cDNA microarrays revealed only two transcripts to be significant differentially expressed by DR: up-regulation of malic enzyme (Mod1) and down-regulation of major urinary protein 1 (Mup1). Real-time polymerase chain reaction analysis confirmed these findings and showed, for the high-fat diet groups, an identical expression pattern for Mup1, whereas Mod1 showed an opposed gene expression pattern for the high-fat diet groups. In conclusion, initial weight loss induces transcriptional changes only in a very small number of adipose genes, which also depends on the (restricted) diet used.

The effect of short-term dietary restriction on reference and working memory in adult rats

Thirty-two rats were divided into dietary restricted or ad libitum feeding groups at 70 days of age in order to examine the effects of short-term dietary restriction on performance of the Morris water maze task (a reference memory task) and delayed-matching-to-place (DMTP) task (a working memory task). The dietary restricted rats were kept at a body weight of 280g throughout training. When they reached 93 days old, behavioral training was initiated. Half rats from each group were trained with the water maze task first, followed by the DMTP task, and the other rats in the reversed order. Regardless of the order of the tasks, dietary restriction had no effect on performance on the water maze task. In the DMTP task, restricted rats performed significantly poorer than ad lib rats at 30 minutes delay, but not at 30 seconds delay. These results suggest that dietary restriction has no effect on reference and working memory tasks when the memory load is light, but it causes impairment on the working memory task when the memory load is heavier.

Malnutrition impairs CD11b/CD18 expression on circulating polymorphonuclear neutrophils and subsequent exudation into inflammatory sites in the early phase of glycogen-induced murine peritonitis.

The effects of malnutrition on polymorphonuclear neutrophil (PMN) exudation are not well understood. The purpose of this study was to examine the effects of short-term dietary restriction on adhesion molecule expression on circulating PMNs and PMN exudation into the inflamed site in a glycogen-induced peritonitis model. Twelve mice were randomly assigned to one of two groups. The ad libitum and diet-restricted groups received mouse chow ad libitum (estimated consumption: 132 g/kg per day) and 33 g/kg per day, respectively, for 7 days. Then, 2 mL of a 1% glycogen solution was intraperitoneally administered to all mice. After 4 hours, the animals were killed. Whole blood was drawn by cardiac puncture. Peritoneal exudative cells were harvested by lavaging the peritoneal cavity. Expressions of CD11b, CD18, and CD62L were measured by flow cytometry. Dietary restriction did not affect the numbers of circulating leukocytes, PMNs, or monocytes. However, CD11b and CD18 expressions on circulating PMNs were significantly lower in the diet-restricted than in the ad libitum group. In contrast, CD62L expression on circulating PMNs was not affected by dietary restriction. The number of exudative PMNs was significantly lower in the diet-restricted group than in the ad libitum group. The expressions of CD11b, CD18 and CD62L on exudative PMNs were unaffected by dietary restriction. There was a significant positive correlation between exudative PMN numbers and CD18 expression on circulating PMNs. Severe dietary restriction in our murine model decreased beta2 integrin expression on circulating PMNs and inhibited PMN exudation into inflamed sites in the early phase of inflammation. These events may increase susceptibility to bacterial infection. Nutritional replenishment may improve host defense in part by enhancing PMN adhesion molecule expression.

Effects of short-term dietary restriction on survival of mammary ascites tumor-bearing rats.

We studied the effects of short-term dietary restriction on the survival of 3-4-month-old tumor-free and tumor-bearing Fisher rats. The diet-restricted food regimen consisted of alternate day ad libitum feeding followed by alternate day fasting. Diet-unrestricted control rats were fed ad libitum daily. Six tumor-free rats on the diet-restricted regimen compensated for the dietary restriction by an increase in food consumption during the alternate feeding days, and lost an average of only 2-3% of their weight in 13 days. Six tumor-free rats on a daily ad libitum feeding regimen gained an average of 6.8% in 15 days. The above dietary-restricted regimen was initiated 1 week before 24 rats were inoculated intraperitoneally with 15 million Mat 13762 ascites tumor cells. Sixteen of 24 (66.7%) diet-restricted tumor-bearing hosts and 5/24 (20.8%) diet-unrestricted tumor-bearing hosts survived at 9 days after tumor inoculation (p less than 0.005). Twelve of 24 (50%) diet-restricted tumor-bearing hosts, and 3 of 24 (12.5%) diet-unrestricted tumor-bearing hosts, survived at 10 days after tumor inoculation (p less than 0.025). Thus, the survival of tumor-bearing rats was enhanced by short-term relatively mild dietary restrictions. We suggest that relatively mild dietary restrictions should be included in clinical trials designed to inhibit cancer growth and enhance the survival of human cancer patients.

Effect of dietary restriction on plasma cholesterol and cholesterol excretion in the White Carneau pigeon

The effect of short-term dietary restriction on plasma cholesterol and cholesterol balance was examined in young White Carneau pigeons. Dietary restriction of 1 month increased plasma cholesterol significantly and subsequently decreased to initial levels at 3 months. The fecal excretion of neutral sterols was significantly reduced ( P < 0.001) at both 1 and 3 months following dietary restriction, while the fecal excretion of bile acids showed no significant changes.