Diet restriction and exercise alleviate cognitive reduction of high fat diet (HFD)-induced obese mice by rescuing inflammation-mediated compromised insulin signaling pathway through activating AMPK/SIRT1 signal pathway and suppressing TLR4 signal pathway

Obesity,caused by excessive energy,leads to body weight gain and various diseases,including cognitive impairment.Current studies suggest that diet restriction such as optimal fasting and regular exercise are crucial for improving cognitive capacity.However,further exploration is needed to understand the specific mechanisms of high fat diet(HFD)-induced cognitive decline in obesity.In the present study,4-month-old mice were subjected to HFD feeding for 18 weeks,followed by aerobic exercise and high-intensity intermittent exercise,regular diet feeding,and intermittent fasting for 8 weeks,and then used to evaluate cognitive capacity,inflammation,compromised insulin signaling pathway,and apoptosis in hippocampal tissue,as well as AMPK/SIRT1 and TLR4 signal pathways.Obese mice revealed impaired cognitive capacity as compared with mice fed with regular diets.In contrast,aerobic exercise,high-intensity intermittent exercise,regular diet,and intermittent fasting could inhibit apoptosis caused by inflammation-mediated compromised insulin signaling pathway in hippocampal tissues through activating the AMPK/SIRT1 signal pathway and suppressing the TLR4 signal pathway,thereby rescuing the cognitive impairment of obese mice.Therefore,diet restriction and exercise interventions may play a positive role in reverting obesity-induced cognitive impairment.

The Effect of Macronutrient Restrictions on Gut Microbiome and Biochemical Parameters of Wistar Albino Rats

Macronutrients serve as a source of energy for both gut microbiota and its host. An increase or decrease in macronutrients can either increase or decrease the composition of gut microbiota, leading to gut dysbiosis which has been implicated in many diseases state including non-communicable diseases. To achieve this, seven diets were formulated by restricting 60% of each macronutrient. These diets were fed on 42 albino rats (Wistar), divided into 7 groups of 6 rats each. Group 1 was fed on a normal laboratory chow diet (ND), group 2 received a fat-restricted diet (FRD), group 3 received a protein-restricted diet, (PFD), group 4 received a carbohydrate-restricted diet (CRD), group 5 received a protein and fat-restricted diet (PFRD), group 6 re-ceived a carbohydrate and fat-restricted diet (CFRD) and group 7 received a carbohydrate and protein-restricted diet (CPRD). Feed and water intake were given ad libitum and daily weight and food intake were recorded. The experiment went on for 4 weeks after which animals were sacrificed and intestinal content and blood were collected for analysis (gut microbial composition, glucose, insulin levels, serum lipid, and enzyme). Compared to the control group results showed a decrease in Bacteroides (40.50 - 14.00 CFU), HDL (68.20 - 40.40 mg/dl), and AST (66.62 - 64.74 U/L) in FRD. An increase in AST (66.6 - 69.43 U/L), Bifidobacterial (59.50 - 92.00 CFU) and decreased Bacteroides (40.5 - 19.5 CFU) for PRD was also recorded. CRD reduced Lactobacillus (73 - 33.5 CFU), total bacterial count (129 - 48 CFU), HDL (68.2 - 30.8 mg/dl), and cholesterol (121.44 - 88.65 mg/dl) whereas intestinal composition of E. coli (30.5 - 51.5 CFU) increased. PFRD increased Lactobacillus (73.00 - 102.5 CFU), Bifidobacterial (59.5 - 100 CFU), HDL (68.2 - 74.7 mg/dl), and Triglyceride (111.67 - 146.67 mg/dl) concentration. Meanwhile, a reduction in Bifidobacterial (59.5 - 41.5 CFU), and an increasing of AST (66.62 - 70.30 U/l) were recorded for CFRD. However, Bacteroides (40.5 69.5 CFU), LDL (30.95 - 41.98 mg/dl) increased and Bifidobacterial (59.5 - 38.00 CFU) and HDL (68.2 - 53.5 mg/dl) decreased for CPRD. This work, therefore, concludes that macronutrient restriction causes significant changes in serum marker and enzyme profile, and gut microbial composition which can cause gut dysbiosis and later on could expose the host to inflammatory diseases in the long run.

Dietary Restriction Reduces Blood Lipids and Ameliorates Liver Function of Mice with Hyperlipidemia

Dietary restriction（DR） can delay senescence, prolong lifespan of mammals and improve their learning-memory activity. The purpose of the study was to explore the effects of DR on hypolipidemic action and liver function of mice with hyperlipidemia. To investigate these effects, hyperlipidemia mouse models were established with high-fat diet（HFD）（34% of energy）, then randomly divided into HFD group, DR30% group and DR50% group. Mice in DR30% and DR50% group were respectively supplied with HFD as much as about 70% and 50% of the consumption of HFD in the mice of HFD group. Rats in control group were fed routinely. After DR for 5 weeks, the average body weight, liver weight, liver index, serum lipids and glucose levels in both DR groups decreased significantly as compared with the HFD group（P〈0.05 or P〈0.01）, so did alanine aminotransferase（ALT）, aspartate aminotransferase（AST）, lactate dehydrogenase（LDH） levels and the ratio of LDL-C/HDL-C in the DR50% group（P〈0.05 or P〈0.01）. Histopathology examination of liver tissues further proved ameliorative effect of DR on liver function. Western blotting showed that DR significantly increased the expression of silent mating type information regulation 2 homolog 1（SIRT1） in liver and adipose, while notably decreased the expression of peroxisome proliferators-activated receptors-gamma（PPARγ） in adipose（P〈0.05 or P〈0.01）. The increase of SIRT1 and decrease of PPARγ may be a mechanism by which DR reduces blood lipids and ameliorates liver function.

Restricting carbohydrates to fight head and neck cancer——is this realistic?

Head and neck cancers(HNCs) are aggressive tumors that typically demonstrate a high glycolytic rate, which results in resistance to cytotoxic therapy and poor prognosis. Due to their location these tumors specifically impair food intake and quality of life, so that prevention of weight loss through nutrition support becomes an important treatment goal. Dietary restriction of carbohydrates(CHOs) and their replacement with fat, mostly in form of a ketogenic diet(KD), have been suggested to accommodate for both the altered tumor cell metabolism and cancer-associated weight loss. In this review, I present three specific rationales for CHO restriction and nutritional ketosis as supportive treatment options for the HNC patient. These are(1) targeting the origin and specific aspects of tumor glycolysis;(2) protecting normal tissue from but sensitizing tumor tissue to radiation- and chemotherapy induced cell kill;(3) supporting body and muscle mass maintenance. While most of these benefits of CHO restriction apply to cancer in general, specific aspects of implementation are discussed in relation to HNC patients. While CHO restriction seems feasible in HNC patients the available evidence indicates that its role may extend beyond fighting malnutrition to fighting HNC itself.

Age-specific mortality and fecundity of a spider mite under diet restriction and delayed mating

Numerous experimental life-history studies on aging are mainly baised on two classical models—fruit fly Drosophila melanogaster(Meigen)and nematode Caenorhab-ditis elegans(Maupas)—with relatively little attention given to other organisms with different life-history characters.Two-spotted spider mite Tetranychus urticae Koch(Acari:Tetranychidae)differs from many other arthropods in that the females continue their growth in the early adult stage and can reproduce sexually and asexually.In this study,the influences of dietary restriction and delayed mating on the aging patterns of the spider mite were examined with the prevailing survival and reproduction trade-off hypothesis of aging being tested.Significant sex-specific responses of the spider mites were found.The females showed longevity extension on diet restriction(fasting for 2 days in every 4 days)compared with their counterparts being fed ad libitum,and after delayed mating for 9 days,while the males displayed a decrease in lifespan when experiencing diet restriction but were not significantly influenced by delayed mating.Path analysis was used to investigate the relationship between mite survival and reproduction traits,including longevity,female lifetime reproduction,age at first reproduction,early reproductive efforts and late reproductive efforts,yielding no evidence for trade-offs between these life-history traits.The additive effects of dietary restriction and delayed mating in lifespan extension of female spider mites were confirmed,proving that diet restriction is a robust anti-aging intervention,and that later onset of reproduction can prolong adult lifespan in females.

Regular diet is non-inferior to restricted diet after polypectomy with decreased hospitalization length of stay and cost:a randomized–controlled trial

Background There are no data comparing a regular diet with a restricted diet after endoscopic polypectomy in patients with colorectal polyps.The current guidelines also did not provide the detailed information of dietary patterns after polypectomy.In this study,we aimed to evaluate the safety and efficacy of different diets on post-polypectomy outcomes.Methods A total of 302 patients with colorectal polyps who underwent polypectomy were prospectively enrolled between March 2019 and December 2019 in Nanfang Hospital(Guangzhou,China).Enrolled patients were then randomly assigned to a regular diet group or a restricted diet group after polypectomy.The study is a non-inferior design and the primary end point was the post-operative adverse events(AE)rate.Secondary end points included length of stay(LOS)and hospitalization cost.Results Among all the included patients,148 patients received a restricted diet and 154 patients received a regular diet after polypectomy.A total of 376 polyps were removed,with 183 polyps in the restricted diet group and 193 polyps in the regular diet group.Shorter LOS(4.0±1.4 vs 4.8±1.7,P<0.001)and lower hospitalization costs(7,701.63±2,579.07 vs 8,656.05±3,138.53,P=0.001)were observed in the regular diet group.In particular,there was no significant difference in 3-day AE rates between the restricted diet and the regular diet group(1.35%[2/148]vs 2.60%[4/154],P=0.685).Subgroup analysis looking at the number of polyps removed in each patient and different treatmentmodalities also showed similar findings.Conclusion Regular diet should be recommended after polypectomy for polyps<20mm as it can shorten LOS and save hospitalization costs.

Relationships Between Estimated Hourly Energy Balance and Body Composition in Professional Cheerleaders

Purpose We sought to describe and examine the interrelationships between energy intake,body composition,and estimated energy balance.Methods Using self-reported hourly food intake and formula-based energy expenditure(EE)protocols,19 female profes-sional cheerleaders(mean age 25.4 years)were assessed to obtain energy balance(EB)for a typical training day.Energy intake(EI)was predicted using the USDA Food Composition Database SR27,and EE was predicted using the Harris-Benedict equation plus a MET-based relative intensity activity scale.Body composition was predicted using a multi-current,8-mode segmental bioelectrical impedance analysis system.Hourly and daily EB was calculated from EI and EE data.Results Subjects reported a 24 h EI significantly below(P<0.001)the unadjusted predicted energy requirement(1482 kcal vs.2199 kcal,respectively),resulting in an average negative net EB of−720 kcal.Carbohydrate intake was significantly below the minimum recommended level(3.1 g/kg vs.6 g/kg,P<0.001)while protein and fat intakes met the recommended levels.Higher fat intake(g/kg)was significantly associated with a higher EI kcal/kg(r=0.726;P<0.001),which was sig-nificantly associated(r=−0.55;P=0.01)with a lower body fat percent(BF%).Using the median of BF%(20.9)as the cut point,participants with fewer hours in a negative EB had lower BF%(P=0.043)and those with lower BF%spent more time in an EB of±300 kcal(P=0.013).Conclusions These athletes reported low energy intakes that resulted in large EB deficits and/or more hours in a negative EB,which could be counterproductive for achieving a lean body composition overtime.

Low Expression of FGF23 and Its Effect on Rats with Intrauterine Growth Retardation

Objective:To explore the levels of fibroblast growth factor 23(FGF23)during pregnancy and its relationship with intrauterine growth restriction(IUGR).Methods:Pregnant rats were classified into an ad libitum rat chow group(ad libitum rat chow,AD group,n=25)and an undernutrition group(50%of their daily food requirement,UN group,n=25).The levels of maternal serum FGF23,tissue homogenate FGF23,and bone gla protein in fetal rats,and placental FGF23 mRNA and protein expression were examined by enzyme-linked immunosorbent assay,real-time qPCR analysis respectively.Finally,the effect of recombinant FGF23 on the viability of MG-63 cells was determined by cell proliferation assay.Data were analyzed with independent two-tailed t test and one-way analysis of variance.Spearman rank-order correlation coefficients(continuous variables)was performed to determine the relationship of results.Results:The diet restriction induced IUGR in rat offsprings,and the UN group exhibited a significantly lower FGF23 level(P<0.05,n=5).The FGF23 level was increased and peaked in maternal serum on gestation day(GD)15,but peaked in fetal and placenta on GD20.Moreover,the tissue homogenate levels of FGF23 and bone gla protein in fetal rats in both groups were positively correlated(r=0.923,P<0.05;r=0.925,P<0.05,respectively,n=15),FGF23 was localized to both decidual and labyrinth zones,with remarkably higher expression on GD20,P<0.05,n=5.In vitro,recombinant human FGF23 enhanced MG-63 cell viability,P<0.05,n=5.Conclusion:Prenatal undernutrition could decrease the FGF23 expression in fetal rats caused by the mother through the placenta,and induced the IUGR and hindered the ossification.And the FGF23 levels are peaked on GD15 mother but peaked on GD20 placenta and fetuses,these might be associated with the over compensation of maternal placenta on GD20.