Novel dietary strategies to manage sarcopenia.

PURPOSE OF REVIEW: Sarcopenia is a wasting disease, mostly age-related in which muscle strength and mass decline, such as physical performance. With aging, both lower dietary protein intake and anabolic resistance lead to sarcopenia. Moreover, aging and sarcopenia display low-grade inflammation, which also worsen muscle condition. In this review, we focused on these two main targets to study dietary strategies. RECENT FINDINGS: The better understanding in mechanisms involved in sarcopenia helps building combined dietary approaches including physical activity that would slow the disease progression. New approaches include better understanding in the choice of quality proteins, their amount and schedule and the association with antioxidative nutrients. SUMMARY: First, anabolic resistance can be countered by increasing significantly protein intake. If increasing amount remains insufficient, the evenly delivery protein schedule provides interesting results on muscle strength. Quality of protein is also to consider for decreasing risk for sarcopenia, because varying sources of proteins appears relevant with increasing plant-based proteins ratio. Although new techniques have been developed, as plant-based proteins display a lower availability, we need to ensure an adapted overall amount of proteins. Finally, specific enrichment with leucine from whey protein remains the dietary combined approach most studied and studies on citrulline provide interesting results. As cofactor at the edge between anabolic and antioxidative properties, vitamin D supplementation is to recommend. Antioxidative dietary strategies include both fibers, vitamins, micronutrients and polyphenols from various sources for positive effects on physical performance. The ω 3 -polyunsaturated fatty acids also display positive modifications on body composition. Gut microbiota modifiers, such as prebiotics, are promising pathways to improve muscle mass and function and body composition in sarcopenic patients. Nutritional interventions could be enhanced by combination with physical activity on sarcopenia. In healthy older adults, promoting change in lifestyle to get near a Mediterranean diet could be one of the best options. In sarcopenia adults in which lifestyle changes appears unprobable, specific enrichement potentialized with physical activity will help in the struggle against sarcopenia. Longitudinal data are lacking, which makes it hard to draw strong conclusions. However, the effects of a physical activity combined with a set of nutrition interventions on sarcopenia seems promising.

Sex-dependent circadian alterations of both central and peripheral clock genes expression and gut-microbiota composition during activity-based anorexia in mice.

RATIONALE: Patients with anorexia nervosa (AN) often present sleep disorders and circadian hormonal dysregulation. The role of the microbiota-gut-brain axis in the regulation of feeding behavior has emerged during the last decades but its relationships with the circadian rhythm remains poorly documented. Thus, we aimed to characterize the circadian clock genes expression in peripheral and central tissues in the activity-based anorexia mouse model (ABA), as well as the dynamics of the gut-microbiota composition. METHODS: From day 1 to day 17, male and female C57Bl/6 mice were submitted or not to the ABA protocol (ABA and control (CT) groups), which combines a progressive limited access to food and a free access to a running wheel. At day 17, fasted CT and ABA mice were euthanized after either resting (EoR) or activity (EoA) phase (n = 10-12 per group). Circadian clock genes expression was assessed by RT-qPCR on peripheral (liver, colon and ileum) and central (hypothalamic suprachiasmatic nucleus or SCN) tissues. Cecal bacterial taxa abundances were evaluated by qPCR. Data were compared by two-way ANOVA followed by post-tests. RESULTS: ABA mice exhibited a lower food intake, a body weight loss and an increase of diurnal physical activity that differ according with the sex. Interestingly, in the SCN, only ABA female mice exhibited altered circadian clock genes expression (Bmal1, Per1, Per2, Cry1, Cry2). In the intestinal tract, modification of clock genes expression was also more marked in females compared to males. For instance, in the ileum, female mice showed alteration of Bmal1, Clock, Per1, Per2, Cry1, Cry2 and Rev-erbα mRNA levels, while only Per2 and Cry1 mRNAs were affected by ABA model in males. By contrast, in the liver, clock genes expression was more markedly affected in males compared to females in response to ABA. Finally, circadian variations of gut-bacteria abundances were observed in both male and female mice and sex-dependent alteration were observed in response to the ABA model. CONCLUSIONS: This study shows that alteration of circadian clock genes expression at both peripheral and central levels occurs in response to the ABA model. In addition, our data underline that circadian variations of the gut-microbiota composition are sex-dependent.

Anorexia nervosa is an eating disorder with a female predominance. However, the underlying pathophysiological mechanisms are still incompletely understood. Patients with anorexia nervosa often show alterations in circadian rhythm, including sleep disorders and modifications in hormone circadian rhythm. The circadian rhythm is controlled in the central nervous system, particularly in the suprachiasmatic nucleus, but clocks have also been described in peripheral tissues. To better understand the putative role of circadian rhythm in the pathophysiology of anorexia nervosa, we have conducted an experimental study in a rodent model of anorexia nervosa called "activity-based anorexia" on both males and females. Interestingly, we observed that the expression of genes involved in the circadian rhythm is affected by the activity-based anorexia model in both the suprachiasmatic nucleus and peripheral tissues, such as the small intestine and liver. In addition, gut­microbiota also shows circadian variation. Interestingly, the anorexia-induced alterations of circadian variations (clock genes expression and gut­microbiota composition) are sex- and tissue-dependent. For instance, female mice exhibited more marked alterations in the ileum, whereas, in males, modifications were more pronounced in the liver. This study highlights sex-dependent alterations of circadian clock genes expression and of gut­microbiota in response to the anorexia rodent model. Further experiments should be performed to investigate the contribution of these mechanisms in the etiology of anorexia nervosa and the higher prevalence in females.

Effects of Glutamine, Curcumin and Fish Bioactive Peptides Alone or in Combination on Intestinal Permeability in a Chronic-Restraint Stress Model.

Irritable bowel syndrome (IBS), a multifactorial intestinal disorder, is often associated with a disruption in intestinal permeability as well as an increased expression of pro-inflammatory markers. The aim of this study was to first test the impact of treatment with glutamine (Gln), a food supplement containing natural curcumin extracts and polyunsaturated n-3 fatty acids (Cur); bioactive peptides from a fish protein hydrolysate (Ga); and a probiotic mixture containing Bacillus coagulans, Lactobacillus acidophilus, Lactobacillus gasseri and Lactobacillus helveticus. These compounds were tested alone on a stress-based IBS model, the chronic-restraint stress model (CRS). The combination of Gln, Cur and Ga (GCG) was also tested. Eight-week-old C57Bl/6 male mice were exposed to restraint stress for two hours every day for four days and received different compounds every day one week before and during the CRS procedure. Plasma corticosterone levels were measured as a marker of stress, and colonic permeability was evaluated ex vivo in Ussing chambers. Changes in the gene expression of tight junction proteins (occludin, claudin-1 and ZO 1) and inflammatory cytokines (IL1ß, TNFα, CXCL1 and IL10) were assessed using RT-qPCR. The CRS model led to an increase in plasma corticosterone and an increase in colonic permeability compared with unstressed animals. No change in plasma corticosterone concentrations was observed in response to CRS with the different treatments (Gln, Cur, Ga or GCG). Stressed animals treated with Gln, Cur and Ga alone and in combination showed a decrease in colonic permeability when compared to the CRS group, while the probiotic mixture resulted in an opposite response. The Ga treatment induced an increase in the expression of the anti-inflammatory cytokine IL-10, and the GCG treatment was able to decrease the expression of CXCL1, suggesting the synergistic effect of the combined mixture. In conclusion, this study demonstrated that a combined administration of glutamine, a food supplement containing curcumin and polyunsaturated n-3 fatty acids, and bioactive peptides from a fish hydrolysate was able to reduce colonic hyperpermeability and reduce the inflammatory marker CXCL1 in a stress-based model of IBS and could be of interest to patients suffering from IBS.

Involvement of acid sensing ion channel (ASIC)-3 in an acute urinary bladder-colon cross sensitization model in rodent.

Introduction: Irritable bowel syndrome and bladder pain syndrome are both characterized by pain in response to organ distension. Epidemiologic studies showed that these two syndromes are often overlapped. Such overlap may be due to sharing of common extrinsic innervations between the colorectum and the urinary bladder, where cross-sensitization of the urinary bladder and the colon would occur in response to mechanical distension of either organ. The aim of this project was to develop and characterize a rodent model of urinary bladder-colon sensitization and to assess the role of the acid sensing ion channel (ASIC)-3. Methods: Double retrograde labelling was performed to identify extrinsic primary afferent neurons innervating both the colon (Fluororuby) and urinary bladder (Fluorogold) in the L6-S1 dorsal root ganglia (DRG) in Sprague Dawley rats. The phenotype of the colon/urinary bladder co-innervating primary afferent neurons was assessed using immunohistochemistry directed against ASIC-3. Cross-organ sensitization was induced in Sprague Dawley rats by using an echography-guided intravesical administration of acetic acid (0.75%) under brief isoflurane anesthesia. Colonic sensitivity was assessed in conscious rats by measuring abdominal contraction during isobaric colorectal distension (CRD). Measurement of urinary bladder and colonic paracellular permeabilities and tissue myeloperoxidase assay were performed. The involvement of ASIC-3 was assessed by use of S1 intrathecal administration of the ASIC-3 blocker, APETx2 (2.2 µM). Results: Immunohistochemistry showed that 73.1% of extrinsic primary afferent neurons co-innervating the colon and the urinary bladder express ASIC-3. By contrast, extrinsic primary afferent neurons innervating the colon only or the urinary bladder only were positive for ASIC-3 in 39.3% and 42.6%, respectively. Echography-guided intravesical administration of acetic acid resulted in colonic hypersensitivity to colorectal distension. This effect started 1 h post-injection and lasted up to 24 h, and was not longer seen after 3 days after injection. No colonic hyperpermeability and no difference in urinary bladder and colon MPO activity was observed between control and acetic acid-treated rats. Colonic sensitization by intravesical acetic acid administration was prevented by S1 intrathecal administration of APETx2. Conclusion: We developed an acute pelvic cross-organ sensitization model in conscious rat. In this model, cross-organ sensitization is likely to involve S1-L6 extrinsic primary afferents co-innervating the colon and urinary bladder through an ASIC-3 pathway.

Invasion of intestinal cells by Staphylococcus warneri, a member of the human gut microbiota.

Coagulase negative staphylococci (CoNS) are a heterogeneous group of bacteria that colonize different types of human epithelia. These bacteria have a highly variable pathogenic potential ranging from avirulent species to major nosocomial pathogens. Staphylococcus warneri is a CoNS species considered to be nonpathogenic. Here, we identify that S. warneri is a natural member of both human and mouse gut microbiota. In addition, we demonstrate that this bacterium is able to get internalized into human cells. We show that S. warneri efficiently invades several human cell types and, more specifically, intestinal epithelial cells, using actin-dependent mechanisms. In contrast to bona fide pathogens, S. warneri does not actively replicate within intestinal cells or resist killing by macrophages. Together, our results highlight that bacteria from the human gut microbiota that are not associated with a high pathogenic potential, can actively invade intestinal cells and may, in this way, impact intestinal physiology.

Mental health and health behaviours among patients with eating disorders: a case-control study in France.

BACKGROUND: Eating disorders (ED) are a public health concern due to their increasing prevalence and severe associated comorbidities. The aim of this study was to identify mental health and health behaviours associated with each form of EDs. METHODS: A case-control study was performed: cases were patients with EDs managed for the first time in a specialized nutrition department and controls without EDs were matched on age and gender with cases. Participants of this study filled self-administered paper questionnaire (EDs group) or online questionnaire (non-ED group). Collected data explored socio-demographics, mental health including anxiety and depression, body image, life satisfaction, substances and internet use and presence of IBS (Irritable Bowel Syndrome). RESULTS: 248 ED patients (broad categories: 66 Restrictive, 22 Bulimic and 160 Compulsive) and 208 non-ED subjects were included in this study. Mean age was 36.0 (SD 13.0) and 34.8 (SD 11.6) in ED and non-ED groups, respectively. Among patients and non-ED subjects, 86.7% and 83.6% were female, respectively. Body Shape Questionnaire mean score was between 103.8 (SD 46.1) and 125.0 (SD 36.2) for EDs and non-ED group, respectively (p < 0.0001). ED patients had a higher risk of unsatisfactory friendly life, anxiety, depression and IBS than non-ED s (all p < 0.0001) Higher risk of anxiety, depression and IBS was found for the three categories of EDs. Higher risk of smoking was associated only with restrictive ED, while or assault history and alcohol abuse problems were associated only with bulimic ED. The risk of binge drinking was lower in all EDs categories than in non-ED. CONCLUSION: This study highlights the common comorbidities shared by all EDs patients and also identifies some specific features related to ED categories. These results should contribute to the conception of future screening and prevention programs in at risk young population as well as holistic care pathways for ED patients. This case-control study evaluated mental health and health behaviours associated with the main categories of Eating Disorders (EDs). Cases were patients with EDs initiating care in a specialized nutrition department and controls without ED were matched on age and gender with cases. Self-administered paper questionnaires were filled by ED 248 patients (66 Restrictive, 22 Bulimic and 160 Compulsive) and online questionnaire by 241 non-ED controls. Body image satisfaction was significantly worse in ED patients than in controls. (p < 0.0001). Dissatisfactory life, anxiety, depression and irritable bowel syndrome were more found in patients with all EDs categories than in non-ED (p < 0.0001). Smoking risk was increased only in restrictive patients while and assault history and alcohol abuse was increased only in bulimic patients. These results highlight the global burden of ED and related comorbidities and provide useful information for future screening, prevention and care programs.

Association between Endometriosis, Irritable Bowel Syndrome and Eating Disorders: ENDONUT Pilot Study.

Background and aim: Irritable bowel syndrome (IBS), eating disorders (ED) and endometriosis share common pathophysiological mechanisms, involving alterations of the gut−brain axis. The aim of the ENDONUT pilot study was to investigate an association between these three diseases by screening for IBS and ED in patients with endometriosis. Method: We included patients from the CIRENDO cohort (Inter-Regional North-West Cohort of women with ENDOmetriosis) with a recent documented diagnosis of endometriosis of less than 4 years, regardless of age, date of onset of symptoms, type of endometriosis (digestive or not), with or without endometriosis-related digestive surgery. Validated questionnaires were used to screen for IBS (Rome IV, Francis score), ED (SCOFF-F, EAT-26), and anxiety/depression (HAD). Anthropometric data and lifestyle habits were also collected. The primary composite endpoint was SCOFF-F and ROME-IV scores. Results: Among 100 patients meeting inclusion criteria, 54 patients completed all the questionnaires. Of these, 19 had a positive SCOFF-F score (35.2%), 26 had a positive ROME-IV score (48.1%), and 14 patients (25.9%) had both a positive SCOFF-F score and a positive ROME-IV score (p = 0.006). Patients with positive SCOFF-F and ROME-IV scores had significantly higher HAD-anxiety and depression scores (p < 0.05). Conclusion: These results suggest a significant association between IBS, ED and endometriosis. The prevalence of IBS and ED in our population is higher than in the general population. Larger studies are needed to confirm these results, to better understand this triad, and to improve the diagnostic and multidisciplinary therapeutic management of these patients.

Intestinal Epithelial Toll-like Receptor 4 Deficiency Modifies the Response to the Activity-Based Anorexia Model in a Sex-Dependent Manner: A Preliminary Study.

The role of microbiota in eating disorders has recently emerged. Previous data reported that lipopolysaccharides induce anorexia and a decrease of body weight through the activation of toll-like receptor 4 (TLR4). In the activity-based anorexia (ABA) mouse model, an increase of TLR4 expression in intestinal epithelial cells (IEC) has been described. We thus aimed to characterize the role of TLR4 in IEC in the ABA model in male and female mice. For this purpose, Vill-CreERT2-TLR4 LoxP, which are depleted for TLR4 in IEC in response to 4-OH tamoxifen, were submitted (ABA) or not (CT) to the ABA procedure that combined free access to a running wheel and progressive time-limited access to food. We thus compared CT and ABA TLR4IEC-/- mice to CT and ABA TLR4IEC+/+ mice. In response to the ABA model, TLR4IEC+/+ male and female mice exhibited a body weight loss associated to a decrease of lean mass. In TLR4IEC-/- male mice, body weight loss was delayed and less pronounced compared to TLR4IEC+/+ male mice. We did not observe a difference of body weight loss in female mice. The body composition remained unchanged between TLR4IEC-/- and TLR4IEC+/+ mice in both sexes. In both sexes, ABA TLR4IEC+/+ mice exhibited an increase of food-anticipatory activity, as well as an increase of immobility time during the open field test. However, female TLR4IEC-/- mice showed a decrease of the time spent at the centre and an increase of the time spent at the periphery of the open field area, whereas we did not observe differences in the male mice. In conclusion, the invalidation of TLR4 in IEC modified the response to the ABA model in a sex-dependent manner. Further studies should decipher the underlying mechanisms.

A Panax quinquefolius-Based Preparation Prevents the Impact of 5-FU on Activity/Exploration Behaviors and Not on Cognitive Functions Mitigating Gut Microbiota and Inflammation in Mice.

Chemotherapy-related cognitive impairment (CRCI) and fatigue constitute common complaints among cancer patient survivors. Panax quinquefolius has been shown to be effective against fatigue in treated cancer patients. We developed a behavioral C57Bl/6j mouse model to study the role of a Panax quinquefolius-based solution containing vitamin C (Qiseng®) or vitamin C alone in activity/fatigue, emotional reactivity and cognitive functions impacted by 5-Fluorouracil (5-FU) chemotherapy. 5-FU significantly reduces the locomotor/exploration activity potentially associated with fatigue, evokes spatial cognitive impairments and leads to a decreased neurogenesis within the hippocampus (Hp). Qiseng® fully prevents the impact of chemotherapy on activity/fatigue and on neurogenesis, specifically in the ventral Hp. We observed that the chemotherapy treatment induces intestinal damage and inflammation associated with increased levels of Lactobacilli in mouse gut microbiota and increased expression of plasma pro-inflammatory cytokines, notably IL-6 and MCP-1. We demonstrated that Qiseng® prevents the 5-FU-induced increase in Lactobacilli levels and further compensates the 5-FU-induced cytokine release. Concomitantly, in the brains of 5-FU-treated mice, Qiseng® partially attenuates the IL-6 receptor gp130 expression associated with a decreased proliferation of neural stem cells in the Hp. In conclusion, Qiseng® prevents the symptoms of fatigue, reduced chemotherapy-induced neuroinflammation and altered neurogenesis, while regulating the mouse gut microbiota composition, thus protecting against intestinal and systemic inflammation.

Evaluation of a Supervised Adapted Physical Activity Program Associated or Not with Oral Supplementation with Arginine and Leucine in Subjects with Obesity and Metabolic Syndrome: A Randomized Controlled Trial.

Background: In patients with obesity and metabolic syndrome (MetS), lifestyle interventions combining diet, in particular, and physical exercise are recommended as the first line treatment. Previous studies have suggested that leucine or arginine supplementation may have beneficial effects on the body composition or insulin sensitivity and endothelial function, respectively. We thus conducted a randomized controlled study to evaluate the effects of a supervised adapted physical activity program associated or not with oral supplementation with leucine and arginine in MetS-complicated patients with obesity. Methods: Seventy-nine patients with obesity and MetS were randomized in four groups: patients receiving arginine and leucine supplementation (ALs group, n = 20), patients on a supervised adapted physical activity program (APA group, n = 20), patients combining ALs and APA (ALs+APA group, n = 20), and a control group (n = 19). After the baseline evaluation (m0), patients received ALs and/or followed the APA program for 6 months (m6). Body composition, MetS parameters, lipid and glucose metabolism markers, inflammatory markers, and a cardiopulmonary exercise test (CPET) were assessed at m0, m6, and after a 3-month wash-out period (m9). Results: After 6 months of intervention, we did not observe variable changes in body weight, body composition, lipid and glucose metabolism markers, inflammatory parameters, or quality of life scores between the four groups. However, during the CPET, the maximal power (Pmax and Ppeak), power, and O2 consumption at the ventilatory threshold (P(VT) and O2(VT)) were improved in the APA and ALs+APA groups (p < 0.05), as well as the forced vital capacity (FVC). Between m6 and m9, a gain in fat mass was only observed in patients in the APA and ALs+APA groups. Conclusion: In our randomized controlled trial, arginine and leucine supplementation failed to improve MetS in patients with obesity, as did the supervised adapted physical activity program and the combination of both. Only the cardiorespiratory parameters were improved by exercise training.

Fatty acids produced by the gut microbiota dampen host inflammatory responses by modulating intestinal SUMOylation.

The gut microbiota produces a wide variety of metabolites, which interact with intestinal cells and contribute to host physiology. The effect of gut commensal bacteria on host protein SUMOylation, an essential ubiquitin-like modification involved in various intestinal functions, remains, however, unknown. Here, we show that short chain fatty acids (SCFAs) and branched chain fatty acids (BCFAs) produced by the gut microbiota increase protein SUMOylation in intestinal cells in a pH-dependent manner. We demonstrate that these metabolites inactivate intestinal deSUMOylases and promote the hyperSUMOylation of nuclear matrix-associated proteins. We further show that BCFAs inhibit the NF-κB pathway, decrease pro-inflammatory cytokine expression, and promote intestinal epithelial integrity. Together, our results reveal that fatty acids produced by gut commensal bacteria regulate intestinal physiology by modulating SUMOylation and illustrate a new mechanism of dampening of host inflammatory responses triggered by the gut microbiota.

Accuracy of bioimpedance equations for measuring body composition in a cohort of 2134 patients with obesity.

INTRODUCTION: Measuring body composition is an important issue to phenotype patients with obesity and to follow the nutritional care efficiency. Bioelectrical Impedance Analysis (BIA) is a simple and rapid technique. However, validity of BIA in patients with obesity remains controversial. Thus, we aimed to evaluate the validity of several BIA equations to assess body composition in a large cohort of patients with obesity by using dual X ray absorptiometry (DXA) as reference. METHODS: Seven BIA equations have been retrospectively applied on electrical data measured by BIA in patients with obesity with BMI equal or higher than 30 kg/m2 and results were compared to DXA-derived fat mass (FM) and fat-free mass (FFM). BIA and DXA were done the same day after an overnight fasting. Results were compared with Bland-Altman method and Pearson correlation. We also calculated the accuracy defined as the percentage of patients with DXA-BIA difference within ± 10% of DXA measures for FFM and FM. RESULTS: Data from 2134 patients with class I and II obesity (ob1/2, n = 1452, 47.4 ± 14.2 y; 35.0 ± 2.7 kg.m-2) and class III obesity (ob3, n = 682, 48.2 ± 13.9 y; 44.1 ± 3.5 kg.m-2) were analyzed. The best results to evaluate FFM both in ob1/2 and ob3 groups were obtained with Roubenoff's equation: Bland Altman bias at -1.96 and -0.82 kg, Pearson correlation r at 0.93 and 0.87, accuracy at 75.7% and 83.3%, respectively. However, limits of agreements at 95% were high: [-9.42; 5.49 kg] and [-8.16; 6.52 kg]. For FM evaluation, Roubenoff's equation also showed best results for ob1/2 group (bias at -1.17 kg; correlation r at 0.89 and accuracy at 79.1%) but not for ob3 group. In this latter group, Deurenberg's equation exhibited the best results (bias at 2.09 kg; correlation r at 0.81 and accuracy at 76.8%). However, limits of agreements remained high. CONCLUSION: In patients with obesity, Roubenoff BIA equation should be recommended to assess fat free mass, even if limits of agreements remain high.

Intestinal permeability and appetite regulating peptides-reactive immunoglobulins in severely malnourished women with anorexia nervosa.

BACKGROUND & AIMS: In the last decades, the role of microbiota-gut-brain axis has emerged in the regulation of eating behavior and in the pathophysiology of anorexia nervosa (AN) that remains poorly understood. Particularly, a gut-derived dysregulation of immune response has been proposed leading to immunoglobulins directed against appetite-regulating peptides. However, intestinal permeability in patients with anorexia nervosa has been poorly documented. METHODS: In the present prospective case-control study, we thus compared intestinal permeability, appetite-regulating peptides and their reactive immunoglobulins measured in severely malnourished women with AN (n = 17; 28 [21-35] y; 14.9 [14.1-15.2] kg/m2) to healthy volunteers (HV, n = 34; 26 [23-35] y; 22.3 [20.6-23.6] kg/m2). RESULTS: Patients with AN exhibited an increased urinary lactulose/mannitol ratio, both in 0-5 h (0.033 [0.013-0.116]) and 5-24 h samples (0.115 [0.029-0.582]), when compared to HV (0.02 [0.008-0.045], p = 0.0074 and 0.083 [0.019-0.290], p = 0.0174, respectively), suggesting an increased intestinal permeability. Urinary excretion of sucralose and plasma zonulin were not different. The levels of plasma total ghrelin and desacyl-ghrelin were increased in patients with AN compared to HV, whereas plasma leptin concentration was decreased. In addition, αMSH remained unchanged compared to HV. Finally, we did not observe any modification of the levels of total or free αMSH, leptin or ghrelin-reactive immunoglobulin G and M, as well as for their affinity properties. Only, a weak decrease of the dissociation constant (kd) for acyl-ghrelin-reactive IgG was observed in patients with AN (p = 0.0411). CONCLUSIONS: In conclusion, severely malnourished patients with AN show a higher intestinal permeability than HV without evidence of an effect on appetite regulating peptides-reactive immunoglobulins.

Bladder-colon chronic cross-sensitization involves neuro-glial pathways in male mice.

BACKGROUND: Irritable bowel syndrome and bladder pain syndrome often overlap and are both characterized by visceral hypersensitivity. Since pelvic organs share common sensory pathways, it is likely that those syndromes involve a cross-sensitization of the bladder and the colon. The precise pathophysiology remains poorly understood. AIM: To develop a model of chronic bladder-colon cross-sensitization and to investigate the mech-anisms involved. METHODS: Chronic cross-organ visceral sensitization was obtained in C57BL/6 mice using ultrasound-guided intravesical injections of acetic acid under brief isoflurane anesthesia. Colorectal sensitivity was assessed in conscious mice by measuring intracolonic pressure during isobaric colorectal distensions. Myeloperoxidase, used as a marker of colorectal inflammation, was measured in the colon, and colorectal permeability was measured using chambers. c-Fos protein expression, used as a marker of neuronal activation, was assessed in the spinal cord (L6-S1 level) using immunohistochemistry. Green fluorescent protein on the fractalkine receptor-positive mice were used to identify and count microglia cells in the L6-S1 dorsal horn of the spinal cord. The expression of NK1 receptors and MAPK-p38 were quantified in the spinal cord using western blot. RESULTS: Visceral hypersensitivity to colorectal distension was observed after the intravesical injection of acetic acid vs saline (P < 0.0001). This effect started 1 h post-injection and lasted up to 7 d post-injection. No increased permeability or inflammation was shown in the bladder or colon 7 d post-injection. Visceral hypersensitivity was associated with the increased expression of c-Fos protein in the spinal cord (P < 0.0001). In green fluorescent protein on the fractalkine receptor-positive mice, intravesical acetic acid injection resulted in an increased number of microglia cells in the L6-S1 dorsal horn of the spinal cord (P < 0.0001). NK1 receptor and MAPK-p38 levels were increased in the spinal cord up to 7 d after injection (P = 0.007 and 0.023 respectively). Colorectal sensitization was prevented by intrathecal or intracerebroventricular injections of minocycline, a microglia inhibitor, by intracerebroventricular injection of CP-99994 dihydrochloride, a NK1 antagonist, and by intracerebroventricular injection of SB203580, a MAPK-p38 inhibitor. CONCLUSION: We describe a new model of cross-organ visceral sensitization between the bladder and the colon in mice. Intravesical injections of acetic acid induced a long-lasting colorectal hypersensitivity to distension, mediated by neuroglial interactions, MAPK-p38 phosphorylation and the NK1 receptor.

Gut microbiota depletion affects nutritional and behavioral responses to activity-based anorexia model in a sex-dependent manner.

BACKGROUND & AIMS: In the last decade, the role of the microbiota-gut-brain axis in eating behavior and anxiety-depressive disorders has gained increasing attention. Although a gut microbiota dysbiosis has been reported in anorectic patients, its pathophysiological role remains poorly understood. Thus, we aimed to characterize the potential role of gut microbiota by evaluating the effects of its depletion in the Activity-Based Anorexia (ABA) mouse model both in male and female mice. METHODS: Male and female C57Bl/6 mice were submitted (ABA group) or not (CT group) to the ABA protocol, which combines access to a running wheel with a progressive limited food access. Gut microbiota was previously depleted or not by a cocktail of antibiotics (ATB) delivered by oral gavages. We monitored body composition, anxiety-like behavior, leptin and adiponectin plasma levels, hypothalamic and hippocampal neuropeptides mRNA levels, as well as dopamine (DRD) and serotonin (5HT1 and 4) receptors mRNA expression. RESULTS: In response to the ABA model, the body weight loss was less pronounced in ATB-treated ABA compared to untreated ABA, while food intake remained unaffected by ATB treatment. ATB-treated ABA exhibited increased fat mass and decreased lean mass compared to untreated ABA both in male and female mice, whereas but plasma adipokine concentrations were affected in a sex-dependent manner. Only male ABA mice showed a reduced anticipatory physical activity in response to ATB treatment. Similarly, anxiety-like behavior was mainly affected in ATB-treated ABA male mice compared to ATB-treated ABA female mice, which was associated with male-specific alterations of hypothalamic CRH mRNA and hippocampal DRD and 5-HT1A mRNA levels. CONCLUSIONS: Our study provides evidence that ATB-induced gut microbiota depletion triggers alterations of nutritional and behavioral responses to the activity-based anorexia model in a sex-dependent manner.

How the Covid-19 epidemic is challenging our practice in clinical nutrition-feedback from the field.

The viral epidemic caused by the new Coronavirus SARS-CoV-2 is responsible for the new Coronavirus disease-2019 (Covid-19). Fifteen percent of the Covid-19 patients will require hospital stay, and 10% of them will need urgent respiratory and hemodynamic support in the intensive care unit (ICU). Covid-19 is an infectious disease characterized by inflammatory syndrome, itself leading to reduced food intake and increased muscle catabolism. Therefore Covid-19 patients are at high risk of being malnourished, making the prevention of malnutrition and the nutritional management key aspects of care. Urgent, brutal and massive arrivals of patients needing urgent respiratory care and artificial ventilation lead to the necessity to reorganize hospital care, wards and staff. In that context, nutritional screening and care may not be considered a priority. Moreover, at the start of the epidemic, due to mask and other protecting material shortage, the risk of healthcare givers contamination have led to not using enteral nutrition, although indicated, because nasogastric tube insertion is an aerosol-generating procedure. Clinical nutrition practice based on the international guidelines should therefore adapt and the use of degraded procedures could unfortunately be the only way. Based on the experience from the first weeks of the epidemic in France, we emphasize ten challenges for clinical nutrition practice. The objective is to bring objective answers to the most frequently met issues to help the clinical nutrition caregivers to promote nutritional care in the hospitalized Covid-19 patient. We propose a flow chart for optimizing the nutrition management of the Covid-19 patients in the non-ICU wards.

Gut microbiota alteration in a mouse model of Anorexia Nervosa.

BACKGROUND & AIMS: Anorexia Nervosa is a severe disease depending on both biological, psychological and environmental factors. The gut microbiota has recently been proposed as one of the biological factors potentially involved in the onset or maintenance of Anorexia Nervosa. To unravel the potential role of the gut microbiota in this disease, we characterized the dysbiosis occurring in a mouse model of Anorexia and correlated bacteria level changes with different physiological parameters such as body weight, food intake or levels of hypothalamic neuropeptides. METHODS: We used the Activity-Based Anorexia (ABA) mouse model, which combines food restriction and physical activity, and which mimics core features of Anorexia Nervosa. We characterized the gut microbiota alteration in ABA mice by combining 16S rRNA gene sequencing and quantitative PCR analyses of targeted genera or species. RESULTS: We identified 68 amplicon sequence variants (ASVs) with decreased levels and 8 ASVs with increased levels in the cecal content of ABA mice compared to control mice. We observed in particular in ABA mice increases in the abundance of Clostridium cocleatum and several Lactobacillus species and a decrease in the abundance of Burkholderiales compared to control mice. Interestingly, we show that most of the observed gut microbiota alterations are due to food restriction and are not affected by physical activity. In addition, we identified several bacterial groups that correlate with mice body weight, food intake, lean and fat masses as well as with hypothalamic mRNA levels of NPY (Neuropeptide Y) and POMC (Pro-opiomelanocortin). CONCLUSIONS: Our study provides a comprehensive characterization of the gut microbiota dysbiosis occurring in the Activity-Based Anorexia mouse model. These data constitute a valuable resource to further decipher the role of the gut microbiota in the different facets of anorexia pathophysiology, such as functional gastrointestinal disorders, appetite regulation and mood disorders.

Hypermetabolism is a reality in amyotrophic lateral sclerosis compared to healthy subjects.

RATIONALE: Hypermetabolism (HM) in Amyotrophic lateral sclerosis (ALS) is the reflection of a high energy metabolic level, but this alteration seems controversial. The main objective of the study was to confirm the existence of HM during ALS compared to healthy subjects. METHODS: A cohort of ALS patients was compared to a control group without metabolic disorder. The assessment included anthropometric criteria measurements, body composition by bioelectric impedance analysis and resting energy expenditure (REE) by indirect calorimetry. HM was defined as a variation > +10% between measured and calculated REE. Statistical analysis used Mann-Withney and Chi2 tests. Multivariate analysis included logistic regression. RESULTS: 287 patients and 75 controls were included. The metabolic level was higher in ALS patients (1500 kcal/24 h [1290-1693] vs. 1230 kcal/24 h [1000-1455], p < 0.0001) as well as the REE/fat free mass ratio (33.5 kcal/kg/24 h [30.4-37.8] vs. 28.3 kcal/kg/24 h [26.1-33.6], p < 0.0001). 55.0% of ALS patients had HM vs. 13.3% of controls (p < 0.0001). HM was strongly and positively associated with ALS (OR = 9.50 [4.49-20.10], p < 0.0001). CONCLUSIONS: HM in ALS is a reality, which affects more than half of the patients and is associated with ALS. This work confirms a very frequent metabolic deterioration during ALS. The identification of HM can allow a better adaptation of the patients' nutritional intake.

The centenary of the Harris-Benedict equations: How to assess energy requirements best? Recommendations from the ESPEN expert group.

BACKGROUND & AIMS: The year 2019 marked the centenary of the publication of the Harris and Benedict equations for estimation of energy expenditure. In October 2019 a Scientific Symposium was organized by the European Society for Clinical Nutrition and Metabolism (ESPEN) in Vienna, Austria, to celebrate this historical landmark, looking at what is currently known about the estimation and measurement of energy expenditure. METHODS: Current evidence was discussed during the symposium, including the scientific basis and clinical knowledge, and is summarized here to assist with the estimation and measurement of energy requirements that later translate into energy prescription. RESULTS: In most clinical settings, the majority of predictive equations have low to moderate performance, with the best generally reaching an accuracy of no more than 70%, and often lead to large errors in estimating the true needs of patients. Generally speaking, the addition of body composition measurements did not add to the accuracy of predictive equations. Indirect calorimetry is the most reliable method to measure energy expenditure and guide energy prescription, but carries inherent limitations, greatly restricting its use in real life clinical practice. CONCLUSIONS: While the limitations of predictive equations are clear, their use is still the mainstay in clinical practice. It is imperative to recognize specific patient populations for whom a specific equation should be preferred. When available, the use of indirect calorimetry is advised in a variety of clinical settings, aiming to avoid under-as well as overfeeding.