The Influence of Obesity and Weight Loss on the Bioregulation of Innate/Inflammatory Responses: Macrophages and Immunometabolism

Effects of different lipid sources on performance, blood lipid parameters, immune system activity, and expression of TNFα and TLR4 genes in broiler chickens

This study aimed to explore the effects of different lipid sources on the performance, blood lipid parameters, immune system activity, and the expression of TNFα and TLR4 genes in broiler chickens. A total of 500 one-day-old male chicks of the ROSS 308 commercial strain were allocated into four treatment groups with five replicates each (each replicate comprised of 25 chickens), following a randomized design. The treatments were as follows: (1) a diet incorporating palm oil (PO, a source of saturated fatty acids); (2) a diet incorporating flaxseed oil (FO, a source of omega-3); (3) a diet incorporating soybean oil (SO, a source of omega-6); and (4) a diet incorporating olive oil (OO, a source of omega-9). According to the findings, the broiler chickens exhibited a significant increase in body weight gain (BWG) throughout the study when their diet consisted of unsaturated oils, as opposed to a diet including PO. Conversely, the feed conversion ratio (FCR) significantly decreased (P<0.01). The treatment with FO resulted in the highest percentage of lymphocytes and antibody titers against Newcastle and Gumboro diseases, showing a significant difference compared to the treatment with PO (P<0.01). Moreover, the relative expression of TNFα and TLR4 genes was the lowest following the FO treatment, indicating a significant decrease compared to the treatment with PO. Overall, the present findings demonstrated that incorporating omega-3 fatty acids into the diet was more effective in enhancing the growth performance, immune system, and health of broiler chickens.

Putrescine alleviates the oxidative damage of cumulus-oocyte complex via improving fatty acid oxidation

BACKGROUND

Fatty acid oxidation of cumulus-oocyte complex (COC) provides sufficient energy for oocyte maturation. But, the relationship between fatty acid oxidation and oxidative stress in aging follicles, as well as the effect of putrescine, is still unclear.

METHODS

The porcine COCs were randomly divided into four groups and cultured in in vitro maturation (IVM) medium with or without 1 mmol/L putrescine, with 50 μmol/L hydrogen peroxide (H2O2) or with 50 μmol/L H2O2 plus 1 mmol/L putrescine. Oocyte maturation was assessed by the first polar body extrusion. The expressions of genes involved in fatty acid oxidation were detected, and the mitochondrial function was analyzed by themembrane potential.

RESULTS

The maturation rate of oocyte was significantly lower in the H2O2 group when compared with the control group (P＜0.001), and putrescine significantly increased this rate in the H2O2 plus putrescine group when compared with the H2O2 group (P＜0.001). The expressions of LKB1, STRAD, ACC2, AMPKα1 and AMPKα2 mRNAs in cumulus cells (CCs) were significantly downregulated by H2O2 treatment, and partly rescued by putrescine addition (P＜0.05-0.001). However, the changes of LKB1, STRAD, ACC2, AMPKα1 and AMPKα2 mRNAs in oocytes were inapparent. The mitochondrial membrane potential of CCs in the H2O2 group was significantly lower than that in the control group, while putrescine addition significantly increased the mitochondrial membrane potential (P＜0.001).

CONCLUSION

The decrease of oocyte maturation due to oxidative stress is related with the decreased fatty acid oxidation, and putrescine may alleviate the COCs damage via improving fatty acid oxidation.

Elevated body mass index increased the risk of recurrence in Chinese patients with chronic rhinosinusitis

BACKGROUND

Elevated body mass index (BMI) has been associated with an increased prevalence of chronic rhinosinusitis (CRS). However, the impact of BMI on the risk of recurrence of CRS is unknown. This study aimed to investigate the association between BMI and the risk of CRS recurrence.

MATERIAL AND METHODS

A retrospective cohort study was conducted and recruited 1057 CRS patients who underwent functional endoscopic sinus surgery (FESS). All subjects were classified into four groups: "underweight", "normal weight", "overweight", and "obese". Multivariate regression analysis was performed to examine the associations between BMI categories and other factors and the risk of CRS recurrence.

RESULTS

The rate of recurrent CRS was significantly higher in the overweight group and obese group than in the normal weight group (P < 0.05). Unadjusted and adjusted logistic regression analyses demonstrated that overweight and obesity exhibited an increased risk of CRS recurrence as compared to patients with normal weight (P < 0.05). Furthermore, all patients were divided into primary CRS group and recurrent CRS group, and the BMI, duration of disease and rate of allergic rhinitis were vastly increased in the recurrent group than in the primary group (P < 0.05). Univariate and multivariate regression analysis showed that BMI and duration of disease were the dominant risk factors of CRS recurrence (P < 0.05).

CONCLUSION

Overweight and obesity presented significant impacts on the CRS recurrence, and elevated BMI were associated with an increased risk of CRS recurrence independently from traditional risk factors. A longer duration of disease was correlated with a higher risk of CRS recurrence.

Resting metabolic rate, abdominal fat pad and liver metabolic gene expression in female rats provided a snacking diet from weaning to adulthood

Our female rat model with continuous, ad libitum access to snacks and chow from weaning to adulthood closely mimics human feeding behavior from childhood onwards. It causes weight gain, enlarged abdominal fat pads, reduced insulin sensitivity and leptin resistance without an increase in total caloric intake. Our current study investigated if this change in energy partitioning is due to a decrease in resting metabolic rate (RMR). In addition, we determined if carbohydrate and lipid metabolism changes in abdominal fat pads and liver. RMR, using indirect calorimetry, was determined in control and snacking rats every two weeks from Days 28-29 to Days 76-77. RMR decreased with age in both groups, but there was no difference between snacking and control rats at any age. At termination, abdominal fat pads (parametrial, retroperitoneal and mesenteric) and liver samples were collected for determination of gene expression for 21 genes involved in carbohydrate and lipid metabolism using RT-qPCR. Analysis of gene expression data showed a striking difference between metabolic profiles of control and snacking rats in abdominal fat pads and liver, with a distinct segregation of genes for both lipid and carbohydrate metabolism that correlated with an increase in body weight and fat pad weights. Genes involved in lipogenesis were upregulated in abdominal fat pads, while genes involved in adipogenesis, and lipid recycling were upregulated in the liver. In conclusion, snacking in addition to chow from weaning in female rats causes a repartitioning of energy that is not due to depressed RMR in snacking rats. Rather, snacking from weaning causes a shift in gene expression resulting in energy partitioning toward enhanced abdominal fat pad lipogenesis, and adipogenesis and lipid recycling in liver.

Do Intestinal Unicellular Parasites Have a Role in the Inflammatory and Redox Status among the Severely Obese?

The diagnosis of obesity comprises subjects with totally different phenotypes and metabolic profiles. Systemic inflammation and oxidative stress derived from the white adipose tissue are suggested as the link between this disease and the development of insulin resistance and metabolic comorbidities. The presence of unicellular eukaryotic parasites colonizing the human gut ecosystem is a common circumstance, and yet their influence on the inflammatory and redox status of the obese host has not been assessed. Herein, a set of inflammatory and redox biomarkers were assessed together with a parasitological analysis of 97 severely obese subjects. Information was also collected on insulin resistance and on the antioxidant composition of the diet. The global prevalence of intestinal unicellular parasites was 49.5%, with Blastocystis sp. the most prevalent protozoan found (42.3%). Colonized subjects displayed a higher total antioxidant capacity and a trend towards higher extracellular superoxide dismutase activity, regardless of their insulin resistance status, along with lower reduced glutathione/oxidized glutathione (GSH/GSSG) ratios in plasma in the insulin-resistant subgroup. No changes in malondialdehyde levels, or in inflammatory cytokines in plasma, were found in regard to the colonization status. In conclusion, enteric eukaryotic unicellular parasites may play an important role in modulating the antioxidant defenses of an obese host, thus could have beneficial effects with respect to the development of systemic metabolic disorders.

An Exploratory Critical Review on TNF-α as a Potential Inflammatory Biomarker Responsive to Dietary Intervention with Bioactive Foods and Derived Products

This review collects and critically examines data on the levels of tumour necrosis factor-alpha (TNF-α) in lean, overweight and obese subjects, and the effects of intervention with different foods and food products containing bioactive constituents in overweight/obese individuals. We additionally explore the influence of different single nucleotide polymorphisms (SNPs) on TNF-α levels and compare the response to food products with that to some anti-obesity drugs. Our aim was to provide an overview of the variability, consistency, and magnitude of the reported effects of dietary factors on TNF-α, and to envisage the reliability of measuring changes in the levels of this cytokine as a biomarker responsive to food intervention in association with the reduction in body weight. Regarding the circulating levels of TNF-α, we report: (i) a large intra-group variability, with most coefficients of variation (CV%) values being ≥30% and, in many cases, >100%; (ii) a large between-studies variability, with baseline TNF-α values ranging from <1.0 up to several hundred pg/mL; (iii) highly variable effects of the different dietary approaches with both statistically significant and not significant decreases or increases of the protein, and the absolute effect size varying from <0.1 pg/mL up to ≈50 pg/mL. Within this scenario of variability, it was not possible to discern clear differentiating limits in TNF-α between lean, overweight, and obese individuals or a distinct downregulatory effect on this cytokine by any of the different dietary approaches reviewed, i.e., polyunsaturated fatty acids (PUFAs), Vitamin-D (VitD), mixed (micro)nutrients, (poly)phenols or other phytochemicals. Further, there was not a clear relationship between the TNF-α responses and body weight changes. We found similarities between dietary and pharmacological treatments in terms of variability and limited evidence of the TNF-α response. Different factors that contribute to this variability are discussed and some specific recommendations are proposed to reinforce the need to improve future studies looking at this cytokine as a potential biomarker of response to dietary approaches.