Adipogenesis is the process by which precursor stem cells differentiate into lipid laden adipocytes. Adipogenesis is regulated by a complex and highly orchestrated gene expression program. In mammalian cells, the peroxisome proliferator-activated receptor γ (PPARγ), and the CCAAT/enhancer binding proteins (C/EBPs) such as C/EBPα, β and δ are considered the key early regulators of adipogenesis, while fatty acid binding protein 4 (FABP4), adiponectin, and fatty acid synthase (FAS) are responsible for the formation of mature adipocytes. Excess accumulation of lipids in the adipose tissue leads to obesity, which is associated with cardiovascular diseases, type II diabetes and other pathologies. Thus, investigating adipose tissue development and the underlying molecular mechanisms is vital to develop therapeutic agents capable of curbing the increasing incidence of obesity and related pathologies. In this review, we address the process of adipogenic differentiation, key transcription factors and proteins involved, adipogenic regulators and potential anti-adipogenic bioactive molecules.

This study was conducted to examine the effects of fructooligosaccharide (FOS) supplementation on growth performance, lymphoid organ weight, intestinal morphology, and immunological status in broilers (n=180) challenged with Salmonella Enteritidis lipopolysaccharides (LPS). Birds were randomly assigned into a 3×2 factorial arrangement that included 1) 3 dietary treatments from d one to 21: positive control (PC), wheat-corn-soybean meal based diet contained antibiotics (virginiamycin and monensin); negative control (NC), as PC without antibiotics; and NC+FOS, as NC supplemented with 0.5% FOS, and 2) 2 intraperitoneal injections: 2 mg/kg Salmonella Enteritidis LPS or sterile phosphate buffered saline (PBS) on d 21. Growth performance and relative lymphoid organ weight were not significantly different among the treatments. Villus height, crypt depth, and total mucosa thickness were significantly increased (P<0.05) in the ileum of broiler chickens fed NC+FOS when compared to PC and NC. Birds in NC+FOS treatment had reduced heterophil but increased monocyte count when compared to NC (P<0.05). Significant diet×challenge interaction was observed on natural IgY levels (P<0.0001), and a significant dietary effect was observed on specific IgY levels in chickens fed NC+FOS (P=0.003). Supplementation of FOS also increased the expression of interleukin (IL)-1ß, -10, and interferon (IFN)-γ mRNA in the ileum of the birds. In summary, Salmonella Enteritidis LPS challenge established significant differences in the immune responses in broiler chickens. FOS supplementation increased ileal mucosa thickness and elevated the expressions of certain cytokine genes. It also led to the alteration of leukocyte compositions and serum IgY levels in response to LPS challenge, suggesting FOS supplementation may be effective to induce protective outcomes in gut health and immunity of broiler chickens.

BackgroundThe bi-directional communication between the oocyte and its companion cumulus cells (CCs) is crucial for development and functions of both cell types. Transcripts that are exclusively expressed either in oocytes or CCs and molecular mechanisms affected due to removal of the communication axis between the two cell types is not investigated at a larger scale. The main objectives of this study were: 1. To identify transcripts exclusively expressed either in oocyte or CCs and 2. To identify those which are differentially expressed when the oocyte is cultured with or without its companion CCs and vice versa.ResultsWe analyzed transcriptome profile of different oocyte and CC samples using Affymetrix GeneChip Bovine Genome array containing 23000 transcripts. Out of 13162 genes detected in germinal vesicle (GV) oocytes and their companion CCs, 1516 and 2727 are exclusively expressed in oocytes and CCs, respectively, while 8919 are expressed in both. Similarly, of 13602 genes detected in metaphase II (MII) oocytes and CCs, 1423 and 3100 are exclusively expressed in oocytes and CCs, respectively, while 9079 are expressed in both. A total of 265 transcripts are differentially expressed between oocytes cultured with (OO + CCs) and without (OO - CCs) CCs, of which 217 and 48 are over expressed in the former and the later groups, respectively. Similarly, 566 transcripts are differentially expressed when CCs mature with (CCs + OO) or without (CCs - OO) their enclosed oocytes. Of these, 320 and 246 are over expressed in CCs + OO and CCs - OO, respectively.While oocyte specific transcripts include those involved in transcription (IRF6, POU5F1, MYF5, MED18), translation (EIF2AK1, EIF4ENIF1) and CCs specific ones include those involved in carbohydrate metabolism (HYAL1, PFKL, PYGL, MPI), protein metabolic processes (IHH, APOA1, PLOD1), steroid biosynthetic process (APOA1, CYP11A1, HSD3B1, HSD3B7). Similarly, while transcripts over expressed in OO + CCs are involved in carbohydrate metabolism (ACO1, 2), molecular transport (GAPDH, GFPT1) and nucleic acid metabolism (CBS, NOS2), those over expressed in CCs + OO are involved in cellular growth and proliferation (FOS, GADD45A), cell cycle (HAS2, VEGFA), cellular development (AMD1, AURKA, DPP4) and gene expression (FOSB, TGFB2).ConclusionIn conclusion, this study has generated large scale gene expression data from different oocyte and CCs samples that would provide insights into gene functions and interactions within and across different pathways that are involved in the maturation of bovine oocytes. Moreover, the presence or absence of oocyte and CC factors during bovine oocyte maturation can have a profound effect on transcript abundance of each cell types, thereby showing the prevailing molecular cross-talk between oocytes and their corresponding CCs.

The immediate post-weaning period poses a major challenge on the survival of piglets. Similarly, newly hatched chicks face life threatening challenges due to enteric infections. In the past several years, in-feed antibiotics have been used to reduce these production problems and improve growth. However, in-feed antibiotics have been banned in many jurisdictions and therefore the most effective alternatives to in-feed antibiotics must be developed. To date, several studies have been conducted to develop alternatives to antibiotics. One of the potential candidates as alternatives to in-feed antibiotics is resistant starch (RS). Resistance starch is a type of starch that resists enzymatic digestion in the upper parts of the gastrointestinal tract and therefore passes to hindgut where it can be fermented by resident microorganisms. Microbial fermentation of RS in the hindgut results in the production of short chain fatty acids (SCFA). Production of SCFA in turn results in growth and proliferation of colonic and cecal cells, increased expression of genes involved in gut development, and creation of an acidic environment. The acidic environment suppresses the growth of pathogenic microorganisms while selectively promoting the growth of beneficial microbes. Thus, RS has the potential to improve gut health and function by modifying and stabilising gut microbial community and by improving the immunological status of the host. In this review, we discussed the roles of RS in modifying and stabilising gut microbiota, gut health and function, carcass quality, and energy metabolism and growth performance in pigs and poultry.

We have examined the effect of oleic acid (OA) concentrations and incubation time, along with chicken serum (CS), on adipogenic differentiation and expression of adipogenic transcripts in hen preadipocytes. Preadipocytes were treated with (i) an adipogenic cocktail (DMI) containing 500 nM dexamethasone, 0.5 mM 3-isobutyl-1-methylxanthine and 20 µg/mL insulin alone and DMI + 75, 150, 300 or 600 µM OA for 48 h; (ii) DMI + 300 µM OA (DMIOA) for 6, 12, 24 or 48 h; and (iii) foetal bovine serum (FBS), CS, DMI + FBS, DMI + CS, DMIOA + FBS and DMIOA + CS. While FABP4 was significantly expressed with increasing concentrations of OA, the expression of C/EBPβ, LEPR and FAS were unchanged compared with the control. PPARγ2 expression was unchanged across all time-points. A significantly higher level of C/EBPα was measured at 48 h, but the levels of C/EBPβ increased after 12 h. Levels of FABP4 significantly increased with the time of incubation after 12 h, but that of LPL was reduced (P < 0.05) at 6, 24 and 48 h. FABP4 was highly expressed in cells treated with CS, DMI + CS and DMIOA + CS compared to cells treated with FBS, DMI + FBS and DMIOA + FBS. In conclusion, increased concentrations of OA and incubation time increases lipid accumulation; FABP4 and C/EBPβ are potential transcription factors regulating OA induced adipogenesis of fat cells obtained from laying hen. CS is a potent inducer of adipogenic differentiation in hen preadipocytes.