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The gut microbiota refers to the trillions of microorganisms residing in the intestine and is integral in multiple physiological processes of the host. Recent research has shown that gut bacteria play a role in metabolic disorders such as obesity, diabetes, and cardiovascular diseases. The mechanisms by which the gut microbiota affects metabolic diseases are by two major routes: (1) the innate immune response to the structural components of bacteria (e.g., lipopolysaccharide) resulting in inflammation and (2) bacterial metabolites of dietary compounds (e.g., SCFA from fiber), which have biological activities that regulate host functions. Gut microbiota has evolved with humans as a mutualistic partner, but dysbiosis in a form of altered gut metagenome and collected microbial activities, in combination with classic genetic and environmental factors, may promote the development of metabolic disorders. This paper reviews the available literature about the gut microbiota and aforementioned metabolic disorders and reveals the gaps in knowledge for future study.

The influence of calcium and dairy food intake on energy balance is the object of a growing scientific literature. This manuscript presents the information discussed by subject experts during a symposium on calcium and obesity, initially planned to document in a comprehensive manner the role of calcium and dairy food on energy balance and body composition. This manuscript is organized into 13 propositions statements which either resume the presentation of an invited speaker or integrate recent developments in calcium-related obesity research. More specifically, the effects of calcium and dairy consumption on body weight and adiposity level, appetite, weight loss intervention outcome, lipid-lipoprotein profile and the risk to develop metabolic syndrome are discussed together with the metabolic mechanisms proposed to explain these effects. Taken together, the observations presented in this manuscript suggest that calcium and dairy food intake can influence many components of energy and fat balance, indicating that inadequate calcium/dairy intake may increase the risk of positive energy balance and of other health problems.

This randomized, double-blind, placebo-controlled study was conducted to compare the effect of a 15-week weight-reducing programme (2 2900 kJ/d) coupled with a calcium plus vitamin D (calciumþ D) supplementation (600 mg elemental calcium and 5 mg vitamin D, consumed twice a day) or with a placebo, on body fat and on spontaneous energy/macronutrient intake. Sixty-three overweight or obese women (mean age 43 years, mean BMI 32 kg/m 2 ) reporting a daily calcium intake , 800 mg participated in present study. Anthropometric variables, resting energy expenditure and spontaneous energy intake were measured before and after the 15-week programme. The calciumþ D supplementation induced no statistically significant increase in fat mass loss in response to the programme. However, when analyses were limited to very low-calcium consumers only (initial calcium intake #600 mg/d, n 7 for calciumþ D, n 6 for placebo), a significant decrease in body weight and fat mass (P,0·01) and in spontaneous dietary lipid intake (P,0·05) was observed in the calciumþ D but not in the placebo group. In very low-calcium consumers, change in fat mass was positively correlated with change in lipid intake. During the weight-reducing programme, a calciumþ D supplementation was necessary in female overweight/obese very low-calcium consumers to reach significant fat mass loss that seemed to be partly explained by a decrease in lipid intake. We propose that this change in lipid intake could be influenced by a calcium-specific appetite control. The hypothesis that calcium/dairy supplementation might accentuate fat mass loss in the context of a weight-reducing programme in obese individuals compared to a non-supplemented control condition has been demonstrated in some (1,2) , but not all (3) studies. One explanation for this discrepancy could be the difference in habitual calcium intake of participants. Indeed, based on results showing that women consuming less than 600 mg calcium/d had an increased percentage body fat (4) , the existence of a threshold of usual calcium intake below which a supplementation in this mineral would effectively promote fat mass loss is possible. The first objective of the present study was to investigate this hypothesis and to assess the impact of a calcium plus vitamin D (calciumþD) supplementation on the outcome of a weightreducing programme in female low-and very low-calcium consumer (VL-CC) overweight/obese subjects.Up to now, the potential effect of calcium on energy balance and adiposity has been explained by a suppression of calcitriol (1,25-dihydroxyvitamin D) which decreases intra-adipocyte calcium influx and concentration (5) leading to a reduced lipogenic gene expression and stimulation of lipolysis and adipocytes uncoupling protein 2 expression (6,7) .Moreover, a diet high in calcium was also shown to increase 24 h lipid oxidation (8) and to reduce lipid absorption due to the intestinal formation of calcium-fatty acids insoluble 'soaps' that are excreted in the faeces (9) . From another perspective, the idea of ...

The epidemic of obesity is developing faster than the scientific understanding of an efficient way to overcome it, as reflected by the low success rate of short-and long-term weight loss interventions. From a clinical standpoint, this suggests that the body tends to defend a set point of possible genetic origin in the context of a weight-reducing program. As described in this paper, this limited therapeutic success may depend on adaptive thermogenesis, which represents in this case the decrease in energy expenditure (EE) beyond what could be predicted from the changes in fat mass or fat-free mass under conditions of standardized physical activity in response to a decrease in energy intake. This issue has been documented in recent studies that have shown in obese individuals adhering to a weight reduction program a greater than predicted decrease in EE, which in some cases was quantitatively sufficient to overcome the prescribed energy restriction, suggesting a role for adaptive thermogenesis in unsuccessful weight loss interventions and reduced body weight maintenance. As also discussed in this paper, this 'adaptive thermogenesis' can be influenced by environmental factors, which have not been frequently considered up to now. This is potentially the case for plasma organochlorine concentration and oxygen desaturation in obstructive sleep apnea syndrome. It is concluded that health professionals should be aware that in some vulnerable individuals, adaptive thermogenesis can be multicausal, and has the capacity to compensate, at least partly, for the prescribed energy deficit, possibly going beyond any good compliance of some patients.

SummaryGametophytic self-incompatibility (GSI) systems involving the expression of stylar ribonucleases have been described and extensively studied in many plant families including the Solanaceae, Rosaceae and Scrophulariaceae. Pollen recognition and rejection is governed in the style by specific ribonucleases called SRNases, but in many self-incompatibility (SI) systems, modifier loci that can modulate the SI response have been described at the genetic level. Here, we present at the molecular level, the isolation and characterization of two Solanum chacoense homologues of the Nicotiana HT modifier that had been previously shown to be necessary for the SI reaction to occur in N. alata (McClure et al., 1999). HT homologues from other solanaceous species have also been isolated and a phylogenetic analysis reveals that the HT genes fall into two groups. In S. chacoense, these small proteins named ScHT-A and ScHT-B are expressed in the style and are developmentally regulated during anthesis identically to the S-RNases as well as following compatible and incompatible pollination. To elucidate the precise role of each HT isoform, antisense ScHT-A and RNAi ScHT-B lines were generated. Conversion from SI to self-compatibility (SC) was only observed in RNAi ScHT-B lines with reduced levels of ScHT-B mRNA. These results confirm the role of the HT modifier in solanaceous SI and indicate that only the HT-B isoform is directly involved in SI.

Wheat is the most widely adapted crop to abiotic stresses and considered an excellent system to study stress tolerance in spite of its genetic complexity. Recent studies indicated that several hundred genes are either up- or down-regulated in response to stress treatment. To elucidate the function of some of these genes, an interactome of proteins associated with abiotic stress response and development in wheat was generated using the yeast two-hybrid GAL4 system and specific protein interaction assays. The interactome is comprised of 73 proteins, generating 97 interactions pairs. Twenty-one interactions were confirmed by bimolecular fluorescent complementation in Nicotiana benthamiana. A confidence-scoring system was elaborated to evaluate the significance of the interactions. The main feature of this interactome is that almost all bait proteins along with their interactors were interconnected, creating a spider web-like structure. The interactome revealed also the presence of a "cluster of proteins involved in flowering control" in three- and four-protein interaction loops. This network provides a novel insight into the complex relationships among transcription factors known to play central roles in vernalization, flower initiation and abscisic acid signaling, as well as associations that tie abiotic stress with other regulatory and signaling proteins. This analysis provides useful information in elucidating the molecular mechanism associated with abiotic stress response in plants.

Two studies were conducted to compare characteristics of consumers and non-consumers of vitamin and/or dietary supplements (study 1) and to assess the effect of a multivitamin and mineral supplementation during a weight-reducing programme (study 2). Body weight and composition, energy expenditure, and Three-Factor Eating Questionnaire scores were compared between consumers and non-consumers of micronutrients and/or dietary supplements in the Québec Family Study (study 1). In study 2, these variables and appetite ratings (visual analogue scales) were measured in forty-five obese non-consumers of supplements randomly assigned to a double-blind 15-week energy restriction (22930 kJ/d) combined with a placebo or with a multivitamin and mineral supplement. Compared with non-consumers, male consumers of vitamin and/or dietary supplements had a lower body weight (P, 0·01), fat mass (P,0·05), BMI (P,0·05), and a tendency for greater resting energy expenditure (P¼ 0·06). In women, the same differences were observed but not to a statistically significant extent. In addition, female supplements consumers had lower disinhibition and hunger scores (P,0·05). In study 2, body weight was significantly decreased after the weight-loss intervention (P,0·001) with no difference between treatment groups. However, fasting and postprandial appetite ratings were significantly reduced in multivitamin and mineralsupplemented women (P,0·05). Usual vitamin and/or dietary supplements consumption and multivitamin and mineral supplementation during a weight-reducing programme seems to have an appetite-related effect in women. However, lower body weight and fat were more detectable in male than in female vitamin and/or dietary supplements consumers.Obesity: Weight loss: Micronutrients: Energy expenditure: Appetite Above the fundamental roles of physical activity and a macronutrient-balanced diet in the maintenance of a healthy body weight, evidence is pointing toward other dietary factors, admittedly of a lower impact range, that could affect energy balance on a long-term basis and therefore represent an avenue worth considering under obesity treatment circumstances. Ca is a good example of this, as low consumption of this micronutrient has been shown to be inversely associated with body weight and adiposity in many studies (1 -3) . More recently, it was observed in a large cohort of 15 655 individuals that overweight or obese men and women who had a high consumption of multivitamins, vitamin B 6 , vitamin B 12 or Cr had gained less weight than those who had not consumed these supplements over 8-12 years (4) .How vitamins and minerals could be implicated in the regulation of body energy stores is not known. For instance, one could propose that they influence the control of food intake through their roles in neurotransmitter synthesis and regulation in the central nervous system. Vitamins C and B 6 are good examples of this, since they are respectively involved in the hydroxylation and decarboxylation of tryptophan for the synthesis of serotoni...