The British journal of nutrition
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Review Meta Analysis
Effectiveness and safety of orally administered immunotherapy for food allergies: a systematic review and meta-analysis.
The aim of using oral and sublingual immunotherapy with food allergies is to enable the safe consumption of foods containing these allergens in patients with food allergies. In the present study, a systematic review of intervention studies was undertaken; this involved the searching of eleven international databases for controlled clinical trials. We identified 1152 potentially relevant papers, from which we selected twenty-two reports of twenty-one eligible trials (i.e. eighteen randomised controlled trials and three controlled clinical trials). ⋯ Pooling of the safety data revealed an increased risk of local (i.e. minor oropharyngeal/gastrointestinal) adverse reactions with immunotherapy (RR 1·47, 95 % CI 1·11, 1·95); there was a non-significant increased average risk of systemic adverse reactions with immunotherapy (RR 1·08, 95 % CI 0·97, 1·19). There is strong evidence that orally administered immunotherapy can induce immunomodulatory changes and thereby promote desensitisation to a range of foods. However, given the paucity of evidence on longer-term safety, effectiveness and cost-effectiveness, orally administered immunotherapy should not be used outside experimental conditions presently.
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Maternal dietary Zn deficiency during fetal development induces substantial cognitive dysfunctions in the resultant offspring. The mechanism underlying this effect is unclear. The present study evaluated whether the impairments caused by gestational and lactational Zn deficiency are mediated by the hippocampal calmodulin-dependent protein kinase II α (α-CaMKII)/brain-derived neurotrophic factor (BDNF) signalling pathway as well as whether they can be restored by postnatal Zn supplementation. ⋯ The results demonstrated that the ZD group exhibited a significantly longer latency period in the Morris water maze as well as a significantly decreased LTP amplitude compared with the CO and PF groups. α-CaMKII and BDNF protein expression in the hippocampus was significantly reduced in the ZD group. Postnatal Zn supplementation restored the cognitive dysfunction induced by gestational Zn deficiency but could not completely reverse the decreased LTP and α-CaMKII/BDNF protein levels. Our findings suggest that the α-CaMKII/BDNF signalling pathway may be involved in Zn deficiency-induced cognitive and synaptic impairments.
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Controlled Clinical Trial
Glutamate supplementation is associated with improved glucose metabolism following carbohydrate ingestion in healthy males.
Glutamate is linked to the glycolytic process, particularly when co-ingested with carbohydrate, but its effects on glucose metabolism are poorly characterised. The present study aimed to (1) specifically examine the effects of carbohydrate administration on circulating glutamate concentrations and (2) investigate the effect of increased glutamate availability, independent of carbohydrate ingestion, on glucose metabolism. A total of nine participants underwent four trials: (1) glutamate supplement+carbohydrate drink (GLU+CHO); (2) glutamate supplement+placebo drink (GLU); (3) placebo supplement+carbohydrate drink (CHO); (4) placebo supplement+placebo drink (CON). ⋯ The glucose response to a carbohydrate load was blunted when glutamate was increased in the circulation (peak serum glucose: 5.50 (SE 0.54) mmol/l during the GLU+CHO trial v. 7.69 (SE 0.53) mmol/l during the CHO trial, P< 0.05). On average, c-peptide results revealed that insulin secretion did not differ between the GLU+CHO and CHO trials; however, four participants demonstrated increased insulin secretion during the GLU+CHO trial and five participants demonstrated decreased insulin secretion under the same conditions. In conclusion, when administration is staggered, MSG and carbohydrate supplementation can be used to manipulate plasma glutamate; however, future studies should control for this dichotomous insulin response.
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Comparative Study
Comparison of physical activity energy expenditure in Japanese adolescents assessed by EW4800P triaxial accelerometry and the doubly labelled water method.
The present study compared the accuracy of triaxial accelerometry and the doubly labelled water (DLW) method for measuring physical activity (PA) in Japanese adolescents. A total of sixty adolescents aged 12-15 years were analysed. The total energy expenditure (TEE) was measured over 7 d by the DLW method and with an EW4800P triaxial accelerometer (Panasonic Corporation). ⋯ RMR(p), TEE, PA energy expenditure (PAEE) and PAL using RMR(p), and PAL using RMR(m) assessed by the DLW method and accelerometry. The present data showed that while accelerometry estimated TEE accurately, it did not provide the precise measurement of PAEE and PAL. The error in accelerometry was attributed to the prediction error of RMR and assessment in exercise.
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Randomized Controlled Trial
Co-administration of methyl donors along with guanidinoacetic acid reduces the incidence of hyperhomocysteinaemia compared with guanidinoacetic acid administration alone.
Guanidinoacetic acid (GAA) is the natural biosynthetic precursor of creatine, in a metabolic reaction that requires only a methyl group transfer. The use of GAA as a food additive for restoring creatine load in human tissues is rather unexplored and data on efficacy and safety are limited. In particular, an increase in serum homocysteine after GAA administration can be regarded as critical and should be prevented. ⋯ Hyperhomocysteinaemia was found in 55.6 % of participants supplemented with GAA, while no participant experienced hyperhomocysteinaemia in the group supplemented with GAA and methyl donors (P= 0.01). In summary, both interventions strongly influenced creatine metabolism, resulting in a significant increase in fasting serum creatine. The concomitant supplementation of methyl donors along with GAA largely precluded the elevation of serum homocysteine caused by GAA administration alone.