Effects of changing dietary fat content on plasma gut hormone concentrations in diet-induced obese and diet-resistant rats

Interleukin 6 and interleukin 17A serum levels and gene- polymorphisms in the development of early allograft rejection in living donor liver transplant recipients

The aim of this study is to evaluate the role of serum level of Interleukin 6(IL-6) and Interleukin 17 (IL-17) in liver transplantation outcome for living recipients, Analyze the relation between the gene polymorphism and the occurrence of rejection after liver transplantation and Study the relation between the gene polymorphism and the occurrence of different infectious complications. The study was conducted in March 2023 and included 60 healthy volunteers from the National Liver Institute (NLI) blood bank at Menoufia University and 120 live donation liver recipient patients at NLI. During one month of liver transplantation, the cytokine levels (IL-17, IL-6 proteins, IL-6 G-174C, and IL-17 A rs2275913 gene polymorphism) and CD4 levels for 60 patients of 120 live donation liver recipient patients whom early reject transplanted tissue and the same parameters were measured after 6 months follow up for non-reject group. The main finding of this study was that the post-transplant rejection group and the post-transplant non-rejection and control groups differed significantly in the genotype frequency (CC, CG, and GG) or alleles of IL-6 G-174C (p = 0.011). On the other hand IL-17A rs2275913 gene polymorphism and its alleles (p = 0.71) showed no statistically significant difference. We also observed that serum IL-17 levels, with 100% specificity and 100% sensitivity threshold, will be more sensitive and specific than serum IL-6 and CD4 count in differentiating post-transplant rejection from non-rejection patients. The results showed that there was no significant relationship between the genotypes and serum levels of interleukins and the type and degree of rejection. Proinflammatory cytokines might be useful indicators for distinguishing and early identifying unfavorable outcomes after transplantation, allowing for prompt and effective treatment intervention. To evaluate these findings, prospective clinical trials are required.

The modulatory role of high fat feeding on gastrointestinal signals in obesity

The gastrointestinal (GI) tract is a specialized sensory system that detects and responds to constant changes in nutrient- and bacterial-derived intestinal signals, thus contributing to controls of food intake. Chronic exposure to dietary fat causes morphological, physiological and metabolic changes leading to disruptions in the regulatory feeding pathways promoting more efficient fat absorption and utilization, blunted satiation signals and excess adiposity. Accumulating evidence demonstrates that impaired gastrointestinal signals following long-term high fat consumption are, at least partially, responsible for increased caloric intake. This review focuses on the role of dietary fat in modulating oral and post-oral chemosensory signaling elements responsible for lipid detection and responses, including changes in sensitivity to satiation signals, such as GLP-1, PYY and CCK and their impact on food intake and weight gain. Furthermore, the influence of the gut microbiota on mechanisms controlling energy regulation in the face of excessive fat exposure will be explored. The profound influence of dietary fats on altering complex regulatory feeding pathways can result in dysregulation of body weight and development of obesity, while restoration or manipulation of satiation signaling may prove an effective tool in prevention and treatment of obesity.

Slower gastric emptying in high-fat diet induced obese rats is associated with attenuated plasma ghrelin and elevated plasma leptin and cholecystokinin concentrations

Gastrointestinal (GI) motility and gut hormones have been considered to be involved in the development and maintenance of obesity. Our aim was to assess the relationships between gastric emptying (GE), GI transit and gut hormones and leptin concentrations in diet-induced obese rat model. Male 6-week-old Sprague-Dawley rats were fed with a high-fat (HF) diet for 8weeks to generate diet-induced obesity (DIO) and diet resistant (DR) rats. GE, GI transit and plasma ghrelin, cholecystokinin (CCK), PYY and leptin concentrations were determined in DIO, DR and control (CON) rats. The DIO rats had slower GE, higher plasma leptin and CCK concentrations, and lower plasma ghrelin concentration compared with CON and DR rats. GE was correlated with plasma ghrelin (r=0.402, P=0.028), CCK (r=-0.518, P=0.003) and leptin concentration (r=-0.514, P=0.004). The slower GE, which can be considered as an adaptive response aimed at HF diet induced obesity, may be mediated by changes of plasma ghrelin, CCK and leptin concentrations.

Alterations in lipid metabolism and thermogenesis with emergence of brown adipocytes in white adipose tissue in diet-induced obesity-resistant Lou/C rats

Recent studies describe the Lou/C rat as a model of resistance to age- and diet-induced obesity and suggest a preferential channeling of nutrients toward utilization rather than storage under standard feeding conditions. The purpose of the present study was to evaluate lipid metabolism of Lou/C and Wistar rats under a high-fat (HF) diet. Four-month-old male Lou/C and Wistar animals were submitted to a 40% HF diet for 5-9 wk. Evolution of food intake, body weight, and body composition, hormonal parameters, and expression of key transcription factors and enzymes involved in lipid metabolism were determined. Wistar rats developed obesity after 5 wk of HF diet, as previously described. Among the various parameters measured, accumulation of intraperitoneal fat was particularly evident in HF-fed Wistar rats. In these animals, thermogenesis was, however, stimulated as a likely compensatory mechanism against the development of obesity. On the contrary, Lou/C animals failed to develop obesity under such a diet, and intraperitoneal fat, not including epididymal and retroperitoneal fat depots, was virtually absent. Enzyme measurements confirmed lipid utilization rather than storage, which was accompanied by the striking emergence of uncoupling protein-1, characteristic of brown adipocytes, in white adipose tissue, particularly in the subcutaneous depot.