1,3-Butanediol Administration Increases β-Hydroxybutyrate Plasma Levels and Affects Redox Homeostasis, Endoplasmic Reticulum Stress, and Adipokine Production in Rat Gonadal Adipose Tissue

Ketone bodies (KBs) are an alternative energy source under starvation and play multiple roles as signaling molecules regulating energy and metabolic homeostasis. The mechanism by which KBs influence visceral white adipose tissue physiology is only partially known, and our study aimed to shed light on the effects they exert on such tissue. To this aim, we administered 1,3-butanediol (BD) to rats since it rapidly enhances β-hydroxybutyrate serum levels, and we evaluated the effect it induces within 3 h or after 14 days of treatment. After 14 days of treatment, rats showed a decrease in body weight gain, energy intake, gonadal-WAT (gWAT) weight, and adipocyte size compared to the control. BD exerted a pronounced antioxidant effect and directed redox homeostasis toward reductive stress, already evident within 3 h after its administration. BD lowered tissue ROS levels and oxidative damage to lipids and proteins and enhanced tissue soluble and enzymatic antioxidant capacity as well as nuclear erythroid factor-2 protein levels. BD also reduced specific mitochondrial maximal oxidative capacity and induced endoplasmic reticulum stress as well as interrelated processes, leading to changes in the level of adipokines/cytokines involved in inflammation, macrophage infiltration into gWAT, adipocyte differentiation, and lipolysis

Effects of environmental cocaine concentrations on COX and caspase-3 activity, GRP-78, ALT, CRP and blood glucose levels in the liver and kidney of the European eel (Anguilla anguilla)

Abstract Cocaine is one of the most widely used illicit drugs in the world, and as a result of incomplete removal by sewage treatment plants it is found in surface waters, where it represents a new potential risk for aquatic organisms. In this study we evaluated the influence of environmental concentrations of cocaine on the liver and the kidney of the European eel (Anguilla anguilla). The eels were exposed to 20 ng L−1 of cocaine for fifty days, after which, three and ten days after the interruption of cocaine exposure their livers and kidneys were compared to controls. The general morphology of the two organs was evaluated, as well as the following parameters: cytochrome oxidase (COX) and caspase-3 activities, as markers of oxidative metabolism and apoptosis activation, respectively; glucose-regulated protein (GRP)78 levels, as a marker of endoplasmic reticulum (ER)-stress; blood glucose level, as stress marker; serum levels of alanine aminotransferase (ALT), as a marker of liver injury and serum levels of C-reactive protein (CRP), as a marker of the inflammatory process. The liver showed morphologic alterations such as necrotic areas, karyolysis and pyknotic nuclei, while the kidneys had dilated glomeruli and the renal tubules showed pyknotic nuclei and karyolysis. In the kidney, the alterations persisted after the interruption of cocaine exposure. In the liver, COX and caspase-3 activities increased (COX: P = 0.01; caspase-3: P = 0.032); ten days after the interruption of cocaine exposure, COX activity returned to control levels (P = 0.06) whereas caspase-3 activity decreased further (P = 0.012); GRP78 expression increased only in post-exposure recovery specimens (three days: P = 0.007 and ten days: P = 0.008 after the interruption of cocaine exposure, respectively). In the kidney, COX and caspase-3 activities increased (COX: P = 0.02; caspase-3: P = 0.019); after the interruption of cocaine exposure, COX activity remained high (three days: P = 0.02 and ten days: P = 0.029 after the interruption of cocaine exposure, respectively) whereas caspase-3 activity returned to control values (three days: P = 0.69 and ten days: P = 0.67 after the interruption of cocaine exposure, respectively). Blood glucose and serum ALT and CRP levels increased (blood glucose: P = 0.01; ALT: P = 0.001; CRP: 0.015) and remained high also ten days after the interruption of cocaine exposure (blood glucose: P = 0.009; ALT: P = 0.0031; CRP: 0.036). These results suggest that environmental cocaine concentrations adversely affected liver and kidney of this species

High-lard and high-fish-oil diets differ in their effects on function and dynamic behaviour of rat hepatic mitochondria

Background Mitochondria are dynamic organelles that frequently undergo fission and fusion processes, and imbalances in these processes may be involved in obesity and insulin resistance. Aims The present work had the following aims: (a) to evaluate whether the mitochondrial dysfunction present in the hepatic steatosis induced by a high-fat diet is associated with changes in mitochondrial dynamics and morphology; (b) to evaluate whether effects on the above parameters differ between high-lard and high-fish-oil diets, as it has been suggested that fish oil may have anti-obesity and anti-steatotic effects by stimulating fatty acids utilisation. Methods The development of hepatic steatosis and insulin resistance was monitored in rats fed a high-lard or high-fish-oil diet. Immunohistochemical and electronic microscopic observations were performed on liver sections. In isolated liver mitochondria, assessments of fatty acids oxidation rate, proton conductance and oxidative stress (by measuring H2O2 release and aconitase activity) were performed. Western blot and immunohistochemical analyses were performed to evaluate the presence of proteins involved in mitochondrial dynamics (i.e., fusion and fission processes). To investigate the fusion process, mitofusin 2 and autosomal dominant optic atrophy-1 (OPA1) were analysed. To investigate the fission process, the presence of dynamin-related protein 1 (Drp1) and fission 1 protein (Fis1) was assessed. Results High-lard feeding elicited greater hepatic lipid accumulation, insulin resistance with associated mitochondrial dysfunction, greater oxidative stress and a shift towards mitochondrial fission processes (versus high-fish-oil feeding, which had an anti-steatotic effect associated with increased mitochondrial fusion processes). Conclusions Different types of high-fat diets differ in their effect on mitochondrial function and dynamic behaviour, leading to different cellular adaptations to over-feeding

Effects of an high-fat diet enriched in lard or in fish oil on the hypothalamic amp-activated protein kinase and inflammatory mediators

The high fat diet (HFD) rich in lard induces obesity, inflammation and oxidative stress, and the deregulation of hypothalamic nuclei plays an important role in this mechanism. One important factor involved in the food intake and inflammation is adenosine monophosphate-dependent kinase (AMPK), a serine/threonine kinase activated by phosphorylation. Omega (&)3-polyunsaturated fatty acids (PUFA) are dietary compounds known to attenuate the obesity-related diseases, although the molecular mechanisms underlying their actions in the hypothalamus are not completely understood. We hypothesized that the beneficial effects of PUFA may be mediated by AMPK in the hypothalamus. To this aim, rats were fed a control diet (CD), or isocaloric HFD containing either fish oil (FD; rich in &3-PUFA) or lard (LD) for 6 weeks, and the activation of AMPK, inflammatory state (IKKb, TNF-a) and oxidative stress were analyzed in the hypothalamus. In addition, we also studied serum lipid profile, homeostatic model assessment (HOMA) index, and pro-inflammatory parameters. Our results showed, at the hypothalamic level of LD-fed rats, an increase of AMPK activation, inflammation and oxidative stress, while no modifications were detected in FD-fed animals compared to CD. In addition body weight gain, serum lipid profile, pro-inflammatory parameters and insulin resistance were reduced in FD animals compared to LD. In conclusion, our data indicate that the substitution of saturated by unsaturated fatty acids in the diet has beneficial effects on modulation of hypothalamic inflammation and function in obesity, underlying, at hypothalamic level, the interaction among insulin and/or leptin resistance, AMPK activation and hyperphagia

Effects of an high-fat diet enriched in lard or in fish oil on the hypothalamic amp-activated protein kinase and inflammatory mediators.

The high fat diet (HFD) rich in lard induces obesity, inflammation and oxidative stress, and the deregulation of hypothalamic nuclei plays an important role in this mechanism. One important factor involved in the food intake and inflammation is adenosine monophosphate-dependent kinase (AMPK), a serine/threonine kinase activated by phosphorylation. Omega (ω)3-polyunsaturated fatty acids (PUFA) are dietary compounds known to attenuate the obesity-related diseases, although the molecular mechanisms underlying their actions in the hypothalamus are not completely understood. We hypothesized that the beneficial effects of PUFA may be mediated by AMPK in the hypothalamus. To this aim, rats were fed a control diet (CD), or isocaloric HFD containing either fish oil (FD; rich in ω3-PUFA) or lard for 6 weeks, and the activation of AMPK, inflammatory state (IKKβ, TNF-α) and oxidative stress were analyzed in the hypothalamus. In addition, we also studied serum lipid profile, homeostatic model assessment (HOMA) index, and pro-inflammatory parameters. Our results showed, at the hypothalamic level of LD-fed rats, an increase of AMPK activation, inflammation and oxidative stress, while no modifications were detected in FD-fed animals compared to CD. In addition body weight gain, serum lipid profile, pro-inflammatory parameters and insulin resistance were reduced in FD animals compared to LD. In conclusion, our data indicate that the substitution of saturated by unsaturated fatty acids in the diet has beneficial effects on modulation of hypothalamic inflammation and function in obesity, underlying, at hypothalamic level, the interaction among insulin and/or leptin resistance, AMPK activation and hyperphagia

Multidisciplinary haematology as prognostic device in environmental and xenobiotic stress-induced response in fish

The variations of haematological parameters hematocrit, hemoglobin concentration, leukocyte and erythrocyte count have been used as pollution and physiological indicators of organic dysfunction in both environmental and aquaculture studies. These parameters are commonly applied as prognostic and diagnostic tools in fish health status. However, there are both extrinsic and intrinsic factors to consider when performing a blood test, because a major limitation for field researchers is that the "rules" for animal or human haematology do not always apply to wildlife. The main objective of this review is to show how some environmental and xenobiotic factors are capable to modulating the haematic cells. Visualizing the strengths and limitations of a haematological analysis in the health assessment of wild and culture fish. Finally, we point out the importance of the use of mitochondrial activities as part of haematological evaluations associated to environment or aquaculture stress

Skeletal muscle mitochondrial bioenergetics and morphology in high fat diet induced obesity and insulin resistance: Focus on dietary fat source

It has been suggested that skeletal muscle mitochondria play a key role in high fat (HF) diet induced insulin resistance (IR). Two opposite views are debated on mechanisms by which mitochondrial function could be involved in skeletal muscle IR. In one theory, mitochondrial dysfunction is suggested to cause intramyocellular lipid accumulation leading to IR. In the second theory, excess fuel within mitochondria in the absence of increased energy demand stimulates mitochondrial oxidant production and emission, ultimately leading to the development of IR. Noteworthy, mitochondrial bioenergetics is strictly associated with the maintenance of normal mitochondrial morphology by maintaining the balance between the fusion and fission processes. A shift toward mitochondrial fission with reduction of fusion protein, mainly mitofusin 2, has been associated with reduced insulin sensitivity and inflammation in obesity and IR development. However, dietary fat source during chronic overfeeding differently affects mitochondrial morphology. Saturated fatty acids induce skeletal muscle IR and inflammation associated with fission phenotype, whereas ω-3 polyunsaturated fatty acids improve skeletal muscle insulin sensitivity and inflammation, associated with a shift toward mitochondrial fusion phenotype. The present minireview focuses on mitochondrial bioenergetics and morphology in skeletal muscle IR, with particular attention to the effect of different dietary fat sources on skeletal muscle mitochondria morphology and fusion/fission balance

Mitochondrial Involvement in the Adaptive Response to Chronic Exposure to Environmental Pollutants and High-Fat Feeding in a Rat Liver and Testis

In our modern society, exposure to stressful environmental stimuli, such as pollutants and/or chronic high-fat feeding, continuously induce tissular/organ metabolic adaptation to promote cellular survival. In extreme conditions, cellular death and tissular/organ damage occur. Mitochondria, as a cellular energy source, seem to play an important role in facing cellular stress induced by these environmental stimuli. On the other hand, mitochondrial dysfunction and oxidative stress play a key role in environmental stress-induced metabolic diseases. However, little is known about the combined effect of simultaneous exposure to chronic high-fat feeding and environmental pollutants on metabolic alterations at a tissular and cellular level, including mitochondrial dysfunction and oxidative stress induction. Our research group recently addressed this topic by analysing the effect of chronic exposure to a non-toxic dose of the environmental pollutant dichlorodiphenyldichloroethylene (DDE) associated with high-fat feeding in male Wistar rats. In this review, we mainly summarize our recent findings on mitochondrial adaptive response and oxidative stress induction in the liver, the main tissue involved in fat metabolism and pollutant detoxification, and in male gonads, the main targets of endocrine disruption induced by both high-fat feeding and environmental pollutants