Growth characteristics in laboratory animals fed zinc-deficient, copper-deficient, of histidine-supplemented diets

Host-microbiota interaction helps to explain the bottom-up effects of climate change on a small rodent species

The population cycles of small rodents have puzzled biologists for centuries. There is a growing recognition of the cascading effects of climate change on the population dynamics of rodents. However, the ultimate cause for the bottom-up effects of precipitation is poorly understood, from a microbial perspective. Here, we conducted a precipitation manipulation experiment in the field, and three feeding trials with controlled diets in the laboratory. We found precipitation supplementation facilitated the recovery of a perennial rhizomatous grass (Leymus chinensis) species, which altered the diet composition and increase the intake of fructose and fructooligosaccharides for Brandt’s vole. Lab results showed that this nutrient shift was accompanied by the modulation of gut microbiota composition and functional pathways (especially for the degradation or biosynthesis of L-histidine). Particularly, the relative abundance of Eubacterium hallii was consistently increased after feeding voles with more L. chinensis, fructose or fructooligosaccharide. These modulations ultimately increased the production of short chain fatty acids (SCFAs) and boosted the growth of vole. This study provides evidence that the precipitation pulses cascades through the plant community to affect rodent gut microbiome. Our results highlight the importance of considering host-microbiota interaction when investigating rodent population responses to climate change.

Animal Models of Undernutrition and Enteropathy as Tools for Assessment of Nutritional Intervention

: Undernutrition is a major public health problem leading to 1 in 5 of all deaths in children under 5 years. Undernutrition leads to growth stunting and/or wasting and is often associated with environmental enteric dysfunction (EED). EED mechanisms leading to growth failure include intestinal hyperpermeability, villus blunting, malabsorption and gut inflammation. As non-invasive methods for investigating gut function in undernourished children are limited, pre-clinical models are relevant to elucidating the pathophysiological processes involved in undernutrition and EED, and to identifying novel therapeutic strategies. In many published models, undernutrition was induced using protein or micronutrient deficient diets, but these experimental models were not associated with EED. Enteropathy models mainly used gastrointestinal injury triggers. These models are presented in this review. We found only a few studies investigating the combination of undernutrition and enteropathy. This highlights the need for further developments to establish an experimental model reproducing the impact of undernutrition and enteropathy on growth, intestinal hyperpermeability and inflammation, that could be suitable for preclinical evaluation of innovative therapeutic intervention.

Do children with Wilson's disease have distinct craniofacial morphology? A cephalometric study

OBJECTIVES

Patients with Wilson's disease (WD) develop osseous changes such as osteoporosis, spontaneous fractures, areas of sclerosis and demineralization of maxillary and mandibular bones, and neurologic symptoms including swallowing dysfunctions, which may affect dento-facial growth. However, dento-maxillo-facial structures of these patients have never been investigated. The present study aimed to discover if subjects with WD have different dentofacial structures.

METHODS

Lateral cephalometric films of 13 children (5 males and 8 females) with WD and of 15 normal subjects (6 males and 9 females) were evaluated. Mean ages of the patients and controls were 12.62 ± 3.09 years and 12.01 ± 1.38 years, respectively. Lateral cephalometric cranial films of all subjects were taken in the same cephalostat in a habitual and unstrained body posture. Thirteen linear and 11 angular parameters were measured to describe the craniofacial characteristics of the subjects.

RESULTS

Statistical analysis showed that there is no statistically significant difference between parameters of normal children and children with WD, with the exception of palatal plane inclination. The inclination of palatal plane was higher in children with WD than in normal subjects.

CONCLUSIONS

Children with WD and healthy children have approximately the same dento-maxillo-facial structures. However, increased palatal plane inclination may be a finding of WD.