Long-term glucocorticoid infusion impairs epididymal adipocyte metabolism and maturation and affects miR-150-5p actions.

The most common form of hypercortisolism is iatrogenic Cushing's syndrome. Lipodystrophy and metabolic disorders can result from the use of exogenous glucocorticoids (GC). Adipocytes play an important role in the production of circulating exosomal microRNAs, and knockdown of Dicer promotes lipodystrophy.

Intrauterine food restriction impairs the lipogenesis process in the mesenteric adipocytes from low-birth-weight rats into adulthood.

Background: Intrauterine food restriction (IFR) during pregnancy is associated with low birth weight (LBW) and obesity in adulthood. It is known that white adipose tissue (WAT) plays critical metabolic and endocrine functions; however, this tissue's behavior before weight gain and obesity into adulthood is poorly studied. Thus, we evaluated the repercussions of IFR on the lipogenesis and lipolysis processes in the offspring and described the effects on WAT inflammatory cytokine production and secretion.

Dexamethasone-Induced Adipose Tissue Redistribution and Metabolic Changes: Is Gene Expression the Main Factor? An Animal Model of Chronic Hypercortisolism.

Chronic hypercortisolism has been associated with the development of several metabolic alterations, mostly caused by the effects of chronic glucocorticoid (GC) exposure over gene expression. The metabolic changes can be partially explained by the GC actions on different adipose tissues (ATs), leading to central obesity. In this regard, we aimed to characterize an experimental model of iatrogenic hypercortisolism in rats with significant AT redistribution.

Physiological concentrations of β-hydroxybutyrate do not promote adipocyte browning.

Aims: Previous work has demonstrated that ketogenic diets promote white fat browning; however, the exact mechanisms underlying this phenomenom have yet to be elucidated. Recently, an in vitro study showed that supraphysiological concentrations of β-hydroxybutyrate (βHB) had a strong influence on the induction of adipocyte browning. On the other hand, concentrations in the physiological range, achieved through ketogenic diets and prolonged fasting produce values of 1-3 mM and 4-7 mM, respectively.

Chronic treatment with dexamethasone alters clock gene expression and melatonin synthesis in rat pineal gland at night.

Background: Melatonin is a neuroendocrine hormone that regulates many functions involving energy metabolism and behavior in mammals throughout the light/dark cycle. It is considered an output signal of the central circadian clock, located in the suprachiasmatic nucleus of the hypothalamus. Melatonin synthesis can be influenced by other hormones, such as insulin and glucocorticoids in pathological conditions or during stress.

Combined treatment with melatonin and insulin improves glycemic control, white adipose tissue metabolism and reproductive axis of diabetic male rats.

Aims: Melatonin treatment has been reported to be capable of ameliorating metabolic diabetes-related abnormalities but also to cause hypogonadism in rats. We investigated whether the combined treatment with melatonin and insulin can improve insulin resistance and other metabolic disorders in rats with streptozotocin-induced diabetes during neonatal period and the repercussion of this treatment on the hypothalamic-pituitary-gonadal axis.

Main Methods: At the fourth week of age, diabetic animals started an 8-wk treatment with only melatonin (0.

Chronic low-dose glucocorticoid treatment increases subcutaneous abdominal fat, but not visceral fat, of male Wistar rats.

Aim: Most studies developed to investigate the effects of glucocorticoids chronic treatment on white adipose tissue uses high doses of these hormones. This study analyzes some effects of a chronic, continuous and steady infusion of low-dose hydrocortisone and the relationship with lipid accumulation in white adipose depots in rats.

Main Methods: Nineteen male Wistar rats were divided into control (CON) and cortisol (CORT) groups.

Oral β-hydroxybutyrate increases ketonemia, decreases visceral adipocyte volume and improves serum lipid profile in Wistar rats.

Background: Ketosis can be induced in humans and in animals by fasting or dietary interventions, such as ketogenic diets. However, the increasing interest on the ketogenic state has motivated the development of alternative approaches to rapidly increase ketonemia using less drastic interventions. Here, it was tested whether oral intake of a β-hydroxybutyrate (βHB) mineral salt mixture could increase ketonemia in Wistar rats without any other dietary changes, thereby being a useful model to study ketones effects alone on metabolism.

Early suppression of adipocyte lipid turnover induces immunometabolic modulation in cancer cachexia syndrome.

Cancer cachexia is a multifactorial syndrome characterized by body weight loss, atrophy of adipose tissue (AT) and systemic inflammation. However, there is limited information regarding the mechanisms of immunometabolic response in AT from cancer cachexia. Male Wistar rats were inoculated with 2 × 10 of Walker 256 tumor cells [tumor bearing (TB) rats].

Atkins diet program rapidly decreases atherogenic index of plasma in trained adapted overweight men.

Background: The Atkins diet program is a great example of the application of low carbohydrate diets for obesity, with the intention of weight loss and improvement in cardiovascular risk (CV risk). A good CV risk predictor is the atherogenic index of plasma (AIP) calculated as log (TG/HDL [mmol]), which is strongly affected by serum triglycerides, which in turn is associated with the carbohydrate intake. This study determined the effect of the initial phase of Atkins diet program, consisting in 20 g/day of carbohydrate intake with positive urinary ketones measure, in AIP of 12 adult overweight trained adapted men.

Metabolic adaptations in the adipose tissue that underlie the body fat mass gain in middle-aged rats.

Little is known about adipocyte metabolism during aging process and whether this can influence body fat redistribution and systemic metabolism. To better understand this phenomenon, two animal groups were studied: young-14 weeks old-and middle-aged-16 months old. Periepididymal (PE) and subcutaneous (SC) adipocytes were isolated and tested for their capacities to perform lipolysis and to incorporate D-[U-(14)C]-glucose, D-[U-(14)C]-lactate, and [9,10(n)-(3)H]-oleic acid into lipids.

Pinealectomy interferes with the circadian clock genes expression in white adipose tissue.

Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24-hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev-erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels.

Acute growth hormone administration increases myoglobin expression and Glut4 translocation in rat cardiac muscle cells.

Objective: Oxygen (O2) and glucose are important energy sources for the heart. This study sought to investigate the effects of acute growth hormone (GH) administration on the expression of myoglobin (Mb) and Glut4 glucose transporter, two important limiting factors for O2 and glucose utilization for energy production, in cardiac muscle cells of treated rats.

Methods: Male Wistar rats were sacrificed at 30, 45, 90 and 120 min after a single dose of intraperitoneal (ip) rat GH (1.