Influence of reproductive status,sex hormones and temperature on plasma IGF-I concentrations in sunshine bass (Morone chrysops × Morone saxatilis)

Insulin-like growth factor-I (IGF-I) concentrations in male and female sunshine bass (Morone chrysops × Morone saxatilis) were determined in March, early April, and late April in outdoor ponds at a commercial farm. Female fish were always larger than male fish; however, plasma IGF-I concentrations tended to be higher in male fish and increased as pond temperature and feeding increased in both sexes. Gonadal development was greatest in both sexes in March and declined to a regressed state by the end of April and the same pattern of change occurred with plasma estrogen and testosterone. Growth and IGF-I concentrations in sunshine bass fed estrogen, methyl testosterone, or a control diet were also determined. Growth was reduced in fish fed both sex hormones. Fish fed the control diet had the highest IGF-I levels, androgen-fed fish had intermediate levels, and estrogen-fed fish had the lowest IGF-I concentrations after 4 weeks on the diet. Plasma IGF-I concentrations appeared to respond to increasing temperature in the ponds, and were inversely related to gonadal development and sex hormones. Exogenous sex hormones resulted in a decrease in plasma IGF-I, feeding activity and growth.     

Ionoregulatory and endocrine responses to disturbed salt and water balance in Mozambique tilapia exposed to confinement and handling stress

This study assessed the endocrine and ionoregulatory responses by tilapia (Oreochromis mossambicus) to disturbances of hydromineral balance during confinement and handling. In fresh water (FW), confinement and handling for 0.5, 1, 2 and 6 h produced elevations in plasma cortisol and glucose; a reduction in plasma osmolality was observed at 6 h. Elevations in plasma prolactins (PRL₁₇₇ and PRL₁₈₈) accompanied this fall in osmolality while no effect upon growth hormone (GH) was evident; an increase in insulin-like growth-factor I (IGF-I) occurred at 0.5 h. In seawater (SW), confinement and handling increased plasma osmolality and glucose between 0.5 and 6 h; no effect on plasma cortisol was seen due to variable control levels. Concurrently, both PRLs were reduced in stressed fish with only transient changes in the GH/IGF-I axis. Next, the branchial expression of Na⁺/K⁺/2Cl^? cotransporter (NKCC) and Na⁺/Cl^? cotransporter (NCC) was characterized following confinement and handling for 6 h. In SW, NKCC mRNA levels increased in stressed fish concurrently with elevated plasma osmolality and diminished gill Na⁺, K⁺-ATPase activity; NCC was unchanged in stressed fish irrespective of salinity. Taken together, PRL and NKCC participate in restoring osmotic balance during acute stress while the GH/IGF-I axis displays only modest responses.     

Selection of physiological and metabolic adaptations to food deprivation in the Pyrenean newt Calotriton asper during cave colonisation

Food restriction is one of the major and most common constraints that subterranean animals face in their biotope. Cave-dwelling organisms thus have to cope with fasting periods that can extend from a month to a year. However, adaptive fasting resistance previously found in subterranean fauna has only been highlighted by direct comparisons with phylogenetically distant epigean organisms, which could severely impact conclusions. Here we report physiological and metabolic responses to 42 days of fasting followed by 10 days of refeeding in two populations (one subterranean and one epigean) of Calotriton asper. In the fed state (control), the hypogean population exhibited a hypometabolism together with higher glycogen (+ 25% in liver and muscles) and triglyceride stores (+ 50% in muscles). During the fasting period, cave individuals exhibited a 20% decrease in VO₂ whereas epigean individuals experienced no significant change. In addition, the energetic reserves always remained higher in the hypogean population. According to phylogenic and biogeographic data, cave colonization by this species dates back to less than 10,000 years, suggesting a rapid selection of adaptive traits related to fasting. This study strongly suggests that cave colonization induces a decrease in metabolism together with a higher capacity to accumulate energy reserves and therefore to withstand unpredictable fasting periods.     

Physiological pathways involved in nutritional muscle dystrophy and healing in European sea bass (Dicentrarchus labrax) larvae

The potential muscle regeneration after nutritional dystrophy caused by high dietary DHA contents in fish and the physiological pathways involved are still unknown. To better understand this process, an experiment was conducted for 3 weeks in 14 day-old European sea bass larvae using different DHA ratios (1 or 5%). After this period, part of the larvae fed 5% DHA diet was switched to 1% DHA diet (“wash-out”) for another 2 weeks. Larvae fed 5% DHA diet showed altered oxidative status as indicated by the highest TBARS values, antioxidant enzymes (AOE) expression and incidence of muscular lesions. Accordingly, “washed-out” larvae showed lower dry weight and α-TOH content. IGF-I gene expression was elevated in 5% DHA larvae at 35 dph, suggesting increased muscle mitogenesis that was corroborated by the increase in myosin heavy chain expression. It can be concluded that high dietary DHA contents alter the oxidative status and cause muscular lesions in European sea bass larvae, with morphological and molecular aspects of mammalians muscular degenerative disease.     

Effects of dietary vitamin D3 administration on innate immune parameters of seabream (Sparus aurata L.)

The present study assesses the in vivo effect of vitamin D₃ or cholecalciferol on some innate immune parameters of the gilthead seabream (Sparus aurata L.). Cholecalciferol was orally administered to seabream specimens in a commercial pellet food supplemented with 0 (control); 3750; 18,750 or 37,500 U kg^?1 and fish were sampled after 1, 2 and 4 weeks of treatment. Serum and head– kidney leucocytes were obtained and humoral (peroxidase and complement activity) and cellular (leucocyte peroxidase content, phagocytic, respiratory burst and natural cytotoxic activities) innate immune parameters were measured. Diet supplementation with 37,500 U kg^?1 cholecalciferol for 2 or 4 weeks resulted in a significant increase in phagocytic ability or serum peroxidase content, respectively, whereas the 3750 and 18,750 U kg^?1 supplemented diets led to significant increases in the phagocytic capacity of leucocytes at week 2 compared with the values found in control fish. Natural cytotoxic activity was increased in leucocytes from fish fed for 1 week with 3750 U kg^?1 cholecalciferol. No significant differences were observed in complement activity or in respiratory burst activity in the assayed conditions. These results suggested that dietary vitamin D₃ administration has an effect on the innate immune parameters of gilthead seabream. The immunostimulant effect was greater on the cellular innate immune parameters assayed, suggesting that similar receptors to those present in mammals are involved in the action of this vitamin in the fish immune system.     

Fasting suppresses T cell-mediated immunity in female Mongolian gerbils (Meriones unguiculatus)

Immune defense is important for organisms' survival and fitness. Small mammals in temperate zone often face seasonal food shortages. Generally fasting can suppress immune function in laboratory rodents and little information is available for wild rodents. The present study tested the hypothesis that Mongolian gerbils (Meriones unguiculatus) could inhibit T cell-mediated immunity to adapt to acute fasting. Forty-two females were divided into the fed and fasted groups, in which the latter was deprived of food for 3 days. After 66 h fasting, half of the gerbils in each group were injected with phosphate buffered saline or phytohaemagglutinin (PHA) solution. T cell-mediated immunity assessed by PHA response was suppressed in the fasted gerbils compared with the fed gerbils. The fasted gerbils had lower body fat mass, wet and dry thymus mass, dry spleen mass, white blood cells, serum leptin and blood glucose concentrations, but higher corticosterone concentrations than those of the controls. Moreover, PHA response was positively correlated with body fat mass and serum leptin levels in the immunochallenged groups. Taken together, acute fasting leads to immunosuppression, which might be caused by low body fat mass and low serum leptin concentrations in female Mongolian gerbils.     

Effect of fasting on nychthemeral concentrations of plasma growth hormone (GH), insulin-like growth factor I (IGF-I), and cortisol in channel catfish (Ictalurus punctatus)

This experiment was conducted to characterize the effect of fasting versus satiety feeding on plasma concentrations of GH, IGF-I, and cortisol over a nychthemeron. Channel catfish fingerlings were acclimated for two weeks under a 12L:12D photoperiod, then fed or fasted for 21 d. On day 21, blood samples were collected every 2 h for 24 h. Weight of fed fish increased an average of 66.2% and fasted fish lost 21.7% of body weight on average. Average nychthemeral concentrations of plasma GH were not significantly different between fed (24.7 ng/mL) and fasted (26.8 ng/mL) fish, but average nychthemeral IGF-I concentrations were higher in fed (23.4 ng/mL) versus fasted (17.8 ng/mL) fish. An increase in plasma IGF-I concentrations was observed in fasted fish 2 h after a peak in plasma GH, but not in fed fish. Average nychthemeral plasma cortisol concentrations were higher in fed (14.5 ng/mL) versus fasted (11.0 ng/mL) fish after 21 d. Significant fluctuations and a postprandial increase in plasma cortisol were observed in fed fish and there was an overall increase in plasma cortisol of both fasted and fed fish during the scotophase. The present experiment indicates little or no effect of 21-d fasting on plasma GH levels but demonstrates fasting-induced suppression of plasma IGF-I and cortisol levels in channel catfish.     

The influence of feeding and fasting on plasma metabolites in the dogfish shark (Squalus acanthias)

Dogfish sharks are opportunistic predators, eating large meals at irregular intervals. Here we present a synthesis of data from several previous studies on responses in plasma metabolites after natural feeding and during prolonged fasting (up to 56 days), together with new data on changes in plasma concentrations of amino acids and non-esterified fatty acids. Post-prandial and long-term fasting responses were compared to control sharks fasted for 7 days, a typical inter-meal interval. A feeding frenzy was created in which dogfish were allowed to feed naturally on dead teleosts at two consumed ration levels, 2.6% and 5.5% of body weight. Most responses were more pronounced at the higher ration level. These included increases in urea and TMAO concentrations at 20 h, followed by stability through to 56 days of fasting. Ammonia levels were low and exhibited little short-term response to feeding, but declined to very low values during the extended fast. Glucose and β-hydroxybutyrate both fell after feeding, the latter to a greater and more prolonged extent (up to 60 h), whereas acetoacetate did not change. During prolonged fasting, glucose concentrations were well regulated, but β-hydroxybutyrate increased to 2–3-fold control levels. Total plasma amino acid concentrations increased in a biphasic fashion, with peaks at 6–20 h, and 48–60 h after the meal, followed by homeostasis during the extended fast. Essential and non-essential amino acids generally followed this same pattern, though some exhibited different trends after feeding: taurine, β-alanine, and glycine (decreases or stability), alanine and glutamine (modest prolonged increases), and threonine, serine, asparagine, and valine (much larger short-term increases). Plasma non-esterified fatty acid concentrations declined markedly through 48 h after the 2.6% meal. These data are interpreted in light of companion studies showing elevations in aerobic metabolic rate, urea production, rectal gland function, metabolic base excretion, and activation of ornithine–urea cycle and aerobic enzymes after the meal, and muscle N-depletion but maintenance of osmolality and urea production during long-term fasting.     

Environmental light color affects the stress response of Nile tilapia

We investigated the effects of environmental light colors (blue, yellow and white) on the stress responses (measured by changes in ventilatory frequency – VF) of Nile tilapia to confinement. After 7 days of light treatment, the VF was similar for fish in each color. On the 8th day, fish were confined for 15 min. After release, the post-confinement VF was measured six times (first period: 0, 2 and 4 min; second period: 6, 8 and 10 min). Irrespective of the light color treatment, confinement increased the VF to higher levels during the first post-confinement period than during the second one. When color was analyzed, irrespective of time, fish under white light increased their VF post-confinement, and blue light prevented this effect. We conclude that blue light is the preferred color for Nile tilapia in terms of reducing stress. This finding is in contrast to previous choice test studies that indicated that yellow is their preferred color.     

Effect of a commercial trout diet on liver ultrastructure of fed and fasted yearling coho salmon, Oncorhynchus kisutch Walbaum

Yearling coho salmon were fed either a commercial trout (TC) diet or a diet consisting of homogenized adult Pacific Ocean coho salmon (PS), supplemented with vitamins and minerals. The hepatosomatic index of the TC-fed fish killed 12 h after the last feed or after 4 or 8 weeks of fasting were significantly larger ( P 0.05) than comparable PS-fed groups.
'Light' and'dark' hepatocyte cell types were evident in all groups although the dark cells were less numerous in the fasted fish. Hepatocytes of fasted fish contained markedly more endoplasmic reticulum than fed fish. Hepatocytic glycogen content of the TC-fed fish was higher than in PS-fed fish. Whereas in the TC-fed group hepatic glycogen was still evident in fish fasted for 8 weeks, the hepatocytes of the fasted PS-fed group contained little or no glycogen. The suitability of commercial fish diets for salmonids is discussed.     

Metabolic control of phosphorylase conversion in muscle. Effect of fasting and refeeding on the response of rat diaphragm glycogen phosphorylase, cyclic AMP Dependent protein kinase, and phosphorylase b kinase to adrenergic stimulation.

The influence of fasting and refeeding on the response to adrenergic stimulation of several enzymes involved in glycogen metabolism has been investigated in the isolated, intact rat diaphragm. The in vitro response of the phosphorylase system to terbutaline was found to decrease markedly following fasting. A pronounced increase in this response was seen upon refeeding. This increased responsiveness was normalized by incubation of isolated tissues with palmitate (1.5 mM). Plasma free fatty acid concentration was increased in fasted rats compared to the value found in refed animals. The effect of terbutaline on cyclic AMP concentration and protein kinase activity was not significantly influenced by fasting and refeeding while fasting decreased the effect of terbutaline upon phosphorylase b kinase. Diaphragm glycogen levels were reduced by more than 50% in rats fasted for 24 hours and were significantly increased upon refeeding compared to fed rats. The results indicate that the nutritional state can modulate the sensitivity of the interconverting system for phosphorylase. It is suggested that this modulation might depend upon fatty acid metabolism.     

Effect of thermal stress on metabolic and oxidative stress biomarkers of Hoplosternum littorale (Teleostei,Callichthyidae)

The present study aimed to investigate in Hoplosternum littorale (Hancock, 1828) the effects of different water temperatures (10 °C, 25 °C-control group- and 33 °C) on physiologic and metabolic traits following acute (1 day) and chronic (21 days) exposures. We analyzed several biomarker responses in order to achieve a comprehensive survey of fish physiology and metabolism under the effect of this natural stressor. We measured morphological indices, biochemical and hematological parameters as well as oxidative stress markers. To evaluate energy consumption, muscle and hepatic total lipid, protein and glycogen concentrations were also quantified. Extreme temperatures exposures clearly resulted in metabolic adjustments, being liver energy reserves and plasma metabolites the most sensitive parameters detecting those changes. We observed reduced hepatosomatic index after acute and chronic exposure to 33 °C while glycogen levels decreased at both temperatures and time of exposure tested. Additionally, acute and chronic exposures to 10 °C increased liver lipid content and plasma triglycerides. Total protein concentration was higher in liver and lower in plasma after chronic exposures to 10 °C and 33 °C. Acute exposition at both temperatures caused significant changes in antioxidant enzymes tested in the different tissues without oxidative damage to lipids. Antioxidant defenses in fish failed to protect them when they were exposed for 21 days to 10 °C, promoting higher lipid peroxidation in liver, kidney and gills. According to multivariate analysis, oxidative stress and metabolic biomarkers clearly differentiated fish exposed chronically to 10 °C. Taken together, these results demonstrated that cold exposure was more stressful for H. littorale than heat stress. However, this species could cope with variations in temperature, allowing physiological processes and biochemical reactions to proceed efficiently at different temperatures and times of exposure. Our study showed the ability of H. littorale to resist a wide range of environmental temperatures and contributes for the understanding of how this species is adapted to environments with highly variable physicochemical conditions.     

A Single-Center Open-Label Study To Investigate The Efficacy And Safety Of Repeated Subcutaneous Injections Of Lanreotide Autogel In Patients With Acromegaly Previously Treated With Octreotide

ObjectiveTo evaluate the efficacy of lanreotide Autogel, a depot preparation of a long-acting somatostatin analogue, in patients with acromegaly who were previously treated with octreotide.MethodsIn a prospective single-center, open-label, comparative study, 13 patients were switched from octreotide treatment (baseline) to lanreotide Autogel therapy at a fixed dosage of 90 mg/4 wk. After 6 injections, the dosage was titrated to 60, 90, or 120 mg/4 wk, on the basis of growth hormone (GH) levels, for a further 6 injections. Mean GH and insulinlike growth factor-I (IGF-I) levels were determined at baseline, during treatment (to 48 weeks), and up to 8 weeks after the last injection.ResultsThere was no significant change in the proportion of patients with GH and IGF-I control from baseline to week 48 (GH, 85% to 89%; IGF-I, 46% to 62%). Mean GH levels changed little from baseline, but mean IGF-I levels were significantly lower after 32 weeks (P < .05) and 48 weeks (P < .02). Data collected at 6 and 8 weeks after the last injection suggested that the efficacy of lanreotide Autogel can persist for longer than 4 weeks.ConclusionThis small study suggests that lanreotide Autogel is at least as effective as octreotide in the control of acromegaly and may last for longer than the recommended 4 weeks. It appears to be a useful alternative to long-acting octreotide in the treatment of acromegaly. (Endocr Pract. 2010;16:191-197)     

Increased survival of neonatal pigs by supplementing medium-chain triglycerides in late-gestating sow diets

Two experiments were conducted to study the efficacy and causes of medium-chain triglycerides (MCT) in sow diet in improving the survival of neonatal pigs. In Experiment 1, beginning on d84 of gestation and continuing through d28 of lactation, 51 sows were fed corn–soybean meal diet mixed with either soybean oil (SO; n=17), coconut oil (CO; n=18), or MCT (n=16) in a proportion of 9 : 1 by weight. The highest improvement in survival of pigs by sows fed MCT (p<0.01) or CO (p<0.05) was observed during the first three days after birth in pigs weighing <1100 g at birth, compared with sows fed SO. Their three-day survival was 98.6, 80.0 and 47.6%, respectively, for MCT, CO and SO groups. In Experiment 2, beginning on d84 of gestation and continuing through farrowing, 24 sows, 8 sows per treatment, were fed diets as in Experiment 1. Liver glycogen content of pigs 4 h after born from sows fed MCT (p<0.10) and CO (p<0.01), and muscle glycogen of pigs from sows fed MCT (p<0.01) and CO (p<0.10) were increased, compared to those of pigs from sows fed SO. Plasma albumin was increased by MCT and CO (p<0.01), relative to SO. The results suggest that MCT or CO in sow diets may enhance the body glycogen stores and maturity of pigs at birth and, hence, their survival, particularly in pigs with low birth weight during the first three days of life.     

Growth performance and starch utilization in common carp (Cyprinus carpio L.) in response to dietary chromium chloride supplementation

A nutrition trial was conducted on juvenile common carp (Cyprinus carpio), initial mean body weight 15 ± 0.4 g within a controlled facility at 25 ± 0.5 °C. Six diets containing various levels of supplementary Cr (0, 0.2, 0.5, 1.0, 1.5, and 2.0) mg Cr/kg of diet as Cr chloride hexahydrate were fed to carp for a period of 10 weeks. Lower growth performance was observed in fish fed on the control diet and the diet supplemented with the highest level of Cr (2.0 mg Cr/kg). Although fish fed 0.5 mg Cr/kg showed the best growth performance, this was not significantly different (P > 0.05) from fish fed 1.0 mg Cr/kg. The regression of plasma glucose concentration was linear (R² = 0.97 and P value = 0.001) as the Cr content of the diet increased (up to 1.5 mg Cr/kg).Cr carcass content was elevated with an increasing level of dietary Cr supplementation up to 1.5 mg Cr/kg; but fish fed on the diet supplemented with the highest level of Cr (2.0 mg Cr/kg) showed a decrease in Cr carcass content.Histological examination to evaluate the impact of different Cr supplementation on liver and gut tissues showed notable changes. The higher level of Cr (2.0 mg Cr/kg) in the diet gave rise to elevated hepatocyte vacuolization and changes in gut tissue morphology.It appeared that Cr chloride significantly improved growth within a defined range (0.2–1.5) mg Cr/kg without any negative impact, while 2.0 mg Cr/kg in carp diet seems to be the threshold for the initiation of toxicity.     

High mTORC1 signaling is maintained,while protein degradation pathways are perturbed in old murine skeletal muscles in the fasted state

This study investigated age-associated changes to protein synthesis and degradation pathways in the quadriceps muscles of male C57BL/6J mice at 5 ages, between 4 and 24 months (m). Sarcopenia was evident by 18 m and was accompanied by hyper-phosphorylation of S6K1, indicating increased mTORC1 signaling. Proteasomal and autophagosomal degradation pathways were also impacted by aging. In the 1% NP40 insoluble protein fraction, the abundance of MuRF1 increased at 24 m, while p62 increased at 15 m, and remained elevated at older ages. In addition, we investigated how protein synthesis and degradation pathways are modulated by fasting in young (4 m) and old (24 m) muscles, and showed that old mice respond to fasting less robustly compared with young. Overnight fasting for 16 h caused de-phosphorylation of AKT and molecules downstream of mTORC1 (S6K1, rpS6 and 4E-BP1) in young, but not old muscles. A longer time of fasting (24 h) was required to reduce phosphorylation of these molecules in old mice. Induction of MuRF1 and Fbxo32 mRNA was also more robust in young compared with old muscles following fasting for 16 h. In addition, a 16 h fast reduced ULK1 phosphorylation at the mTORC1 specific site Ser757 only in young muscles. The striking accumulation of insoluble p62 protein in muscles of all old male mice (fed or fasted), suggests age-related dysregulation of autophagy and protein aggregation. These data provide an insight into the mechanisms of metabolic responses that affect protein homeostasis in old skeletal muscles, with applications to design of clinical interventions that target sarcopenia.     

Overwinter fasting and re-feeding in rainbow trout: plasma growth hormone and cortisol levels in relation to energy mobilisation

This study investigated the roles of cortisol and growth hormone (GH) during a period of fasting in overwintering salmonid fish. Indices of carbohydrate (plasma glucose, liver glycogen), lipid (plasma free fatty acids (FFAs)) and protein metabolism (plasma protein, total plasma amino acids) were determined, together with plasma GH, cortisol and somatolactin (SL) levels at intervals in three groups of rainbow trout (continuously fed; fasted for 9 weeks then fed; fasted for 17 weeks). In fasted fish, a decline in body weight and condition factor was accompanied by reduced plasma glucose and hepatic glycogen and increased plasma FFA. No consistent elevation of plasma GH occurred until after 8 weeks of fasting when plasma GH levels increased ninefold. No changes were observed in plasma total protein and AA until between weeks 13 and 17 when both were reduced significantly. When previously fasted fish resumed feeding, plasma glucose and FFA, and hepatic glycogen levels rapidly returned to control values and weight gain resumed. No significant changes in plasma cortisol levels, related to feeding regime, were evident at any point during the study and there was no evidence that SL played an active role in the response to fasting. The results suggest that overwinter fasting may not represent a significant nutritional stressor to rainbow trout and that energy mobilisation during fasting may be achieved without the involvement of GH, cortisol or SL.     

Fasting plasma levels of nesfatin-1 in patients with type 1 and type 2 diabetes mellitus and the nutrient-related fluctuation of nesfatin-1 level in normal humans

The novel satiety factor nesfatin-1 has been shown to decrease food intake and body weight in rodents after i.c.v. injection. However, no further developments regarding the true patho-physiological relevance of nesfatin-1 in obesity and type 1 diabetes mellitus (T1 DM) and type 2 diabetes mellitus (T2 DM) have been reported. A recent study by Stengel et al. demonstrated that a down-regulation of NUCB2 mRNA in gastric endocrine cells was observed after 24-h fasting. They raised the possibility that nesfatin/NUCB2 gene expression may be regulated by nutritional status, suggesting that nesfatin-1 in the stomach might play a role in satiety. In the present study, fasting levels in plasma nesfatin-1, insulin and glucose were measured and analyzed in healthy subjects and in patients with T1 DM and T2 DM. Plasma nesfatin-1 levels were measured 6 times before and after oral glucose ingestion in healthy subjects. No sex differences in plasma nesfatin-1 were found. The mean fasting plasma nesfatin-1 levels were slightly but not significantly higher in T1 DM patients compared to healthy subjects. However, fasting plasma nesfatin-1 levels were significantly lower in T2 DM patients compared to healthy subjects and T1 DM patients. Plasma nesfatin-1 did not change acutely, although a small rise in circulating nesfatin-1 occurred within 30 min after the beginning of an oral glucose ingestion (from a mean basal value of 0.99 ± 0.23 ng/ml to a maximum of 1.08 ± 0.24 ng/ml). No significant difference in plasma nesfatin-1 before and after an oral glucose was observed. In conclusion, we showed that fasting nesfatin-1 was significantly lower in T2 DM patients compared to healthy subjects and T1 DM patients. The significance of this result is unclear but the reduction in fasting nesfatin-1 may be one of the appetite-related hormones involved in diabetic hyperphagia. In addition, neither glucose nor saline ingestions affected plasma nesfatin-1, suggesting that gastric chemosensation is not sufficient for the nesfatin-1 response under the present conditions.     

Dietary fatty acids and oxidative stress in the heart mitochondria

Our study compared the effects of different oils on oxidative stress in rat heart mitochondria, as well as on plasma parameters used as risk factors for cardiovascular disease. The rats were fed for 16 weeks with coconut, olive, or fish oil diet (saturated, monounsaturated, or polyunsaturated fatty acids, respectively). The cardiac mitochondria from rats fed with coconut oil showed the lowest concentration of oxidized proteins and peroxidized lipids. The fish oil diet leads to the highest oxidative stress in cardiac mitochondria, an effect that could be partly prevented by the antioxidant probucol. Total and LDL cholesterols decreased in plasma of rats fed fish oil, compared to olive and coconut oils fed rats. A diet enriched in saturated fatty acids offers strong advantages for the protection against oxidative stress in heart mitochondria.