Effects of chewing on appetite, food intake and gut hormones: A systematic review and meta-analysis

Aim: To conduct a systematic review of the effects of chewing on appetite, food intake and gut hormones, and a meta-analysis of the effects of chewing on self-reported hunger. Objectives: To seek insights into the relationship between chewing, appetite, food intake and gut hormones, and to consider potentially useful recommendations to promote benefits of chewing for weight management. Materials and methods: Papers were obtained from two electronic databases (Medline and Cochrane), from searches of reference lists, and from raw data collected from the figures in the articles. A total of 15 papers were identified that detailed 17 trials. All 15 papers were included in the systematic review; however, a further five studies were excluded from the meta-analysis because appropriate information on hunger ratings was not available. The meta-analysis was conducted on a total of 10 papers that detailed 13 trials. Results: Five of 16 experiments found a significant effect of chewing on satiation or satiety using self-report measures (visual analogue scales, VASs). Ten of 16 experiments found that chewing reduced food intake. Three of five studies showed that increasing the number of chews per bite increased relevant gut hormones and two linked this to subjective satiety. The meta-analysis found evidence of both publication bias and between study heterogeneity (IA2=93.4%, tau2=6.52, p<0.001) which decreased, but remained, when covariates were considered. Analysis of the heterogeneity found a substantial effect of the fasting period where the duration of fasting influenced the decrease in hunger due to chewing. Prolonged mastication significantly reduces self-reported hunger levels (hunger: -2.31 VAS point, 95% CI [-4.67, -1.38], p<0.001). Conclusions: Evidence currently suggests that chewing may decrease self-reported hunger and food intake, possibly through alterations in gut hormone responses related to satiety. Although preliminary, the results identify a need for additional research in the area. Focused, uniform, experimental designs are required to clearly understand the relationships that exist between mastication, appetite, satiety, food intake and, ultimately, body weight

Neuroendocrine factors regulate retinoic acid receptors in normal and hypoplastic lung development

Congenital diaphragmatic hernia (CDH) is characterised by a spectrum of lung hypoplasia and consequent pulmonary hypertension, leading to high morbidity and mortality rates. Moreover, CDH has been associated with an increase in the levels of pulmonary neuroendocrine factors, such as bombesin and ghrelin, and a decrease in the action of retinoic acid (RA). The present study aimed to elucidate the interaction between neuroendocrine factors and RA. In vitro analyses were performed on Sprague-Dawley rat embryos. Normal lung explants were treated with bombesin, ghrelin, a bombesin antagonist, a ghrelin antagonist, dimethylsulfoxide (DMSO), RA dissolved in DMSO, bombesin plus RA and ghrelin plus RA. Hypoplastic lung explants (nitrofen model) were cultured with bombesin, ghrelin, bombesin antagonist or ghrelin antagonist. The lung explants were analysed morphometrically, and retinoic acid receptor (RAR) α, β and γ expression levels were assessed via Western blotting. Immunohistochemistry analysis of RAR was performed in normal and hypoplastic lungs 17.5 days post-conception (dpc). Compared with the controls, hypoplastic lungs exhibited significantly higher RARα/γ expression levels. Furthermore considering hypoplastic lungs, bombesin and ghrelin antagonists decreased RARα/γ expression. Normal lung explants (13.5 dpc) treated with RA, bombesin plus RA, ghrelin plus RA, bombesin or ghrelin exhibited increased lung growth. Moreover, bombesin and ghrelin increased RARα/γ expression levels, whereas the bombesin and ghrelin antagonists decreased RARα/γ expression. This study demonstrates for the first time that neuroendocrine factors function as lung growth regulators, sensitising the lung to the action of RA through up-regulation of RARα and RARγ.P.P.-T. was supported by the Fundação para a Ciência e a Tecnologia (ref. SFRH/BD/73660/2010). R.S.M. was supported by the ON.2 SR&TD Integrated Program (N-01-01-01-24-01-07) (ref. UMINHO/BPD/31/2013). The funding bodies had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Guidelines for the management of pregnancy in women with cystic fibrosis

Women with cystic fibrosis (CF) now regularly survive into their reproductive years in good health and wish to have a baby. Many pregnancies have been reported in the literature and it is clear that whilst the outcome for the baby is generally good and some mothers do very well, others find either their CF complicates the pregnancy or is adversely affected by the pregnancy. For some, pregnancy may only become possible after transplantation. Optimal treatment of all aspects of CF needs to be maintained from the preconceptual period until after the baby is born. Clinicians must be prepared to modify their treatment to accommodate the changing physiology during pregnancy and to be aware of changing prescribing before conception, during pregnancy, after birth and during breast feeding. This supplement offers consensus guidelines based on review of the literature and experience of paediatricians, adult and transplant physicians, and nurses, physiotherapists, dietitians, pharmacists and psychologists experienced in CF and anaesthetist and obstetricians with experience of CF pregnancy. It is hoped they will provide practical guidelines helpful to the multidisciplinary CF teams caring for pregnant women with CF

ETUDE DES MECANISMES CELLULAIRES ET MOLECULAIRES DE LA REGULATION DE LA MOBILISATION DES RESERVES HEPATIQUES DE VITAMINE A (DOCTORAT (NUTRITION))

CLERMONT FD-BCIU-Santé (631132104) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Do the lactotripeptides isoleucine-proline-proline and valine-proline-proline reduce systolic blood pressure in European subjects? A meta-analysis of randomized controlled trials.

BACKGROUND: The milk-derived peptides isoleucine-proline-proline (IPP) and valine-proline- proline (VPP) have been shown to reduce systolic blood pressure (SBP). This decrease is convincingly shown in subjects of Asian origin, but less consistent results have been obtained in European populations. METHODS: A meta-analysis was conducted in accord with the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) requirements, to assess the effect of IPP and VPP on SBP in Europeans, and to explore some determinants of this effect. RESULTS: Ninety-one publications on the effect of IPP and VPP on SBP in Europeans were identified, and 14 trials with 15 sets of data (n = 1,306) met the inclusion criteria for the meta-analysis. A random-effects model (using the restricted maximum likelihood (REML) estimator) was used for the analysis. Although not all individual trials showed a statistically significant effect of IPP or VPP in reducing SBP, the combination of all data for the two peptides yielded a statistically significantly greater effect for IPP/VPP than for placebo. The decrease in SBP with IPP/VPP was 1.28mm Hg (95% CI, -2.09 to -0.48, P = 0.0017) and the decrease in diastolic BP (DBP) was 0.59mm Hg (95% CI, -1.18 to -0.01, P = 0.047). There was no evidence in the meta-analysis of any publication bias or of heterogeneity (P = 0.13). Among other features, a significant effect was seen for age, with each additional year of age reducing the effect on SBP by 0.09mm Hg. This might be related to isolated systolic hypertension, a condition often encountered in the elderly, who may be poorly responsive to first-line treatments for hypertension. CONCLUSION: The peptides IPP and VPP are effective in moderately reducing SBP in European subjects, as is known for Asian populations. These two peptides could therefore have a role in controlling blood pressure (BP), a prospect that merits their further study