Long-term obesity is associated with depression and neuroinflammation

ABSTRACT Objective: Obesity is characterized by a state of chronic, low-intensity systemic inflammation frequently associated with insulin resistance and dyslipidemia. Materials and methods: Given that chronic inflammation has been implicated in the pathogenesis of mood disorders, we investigated if chronic obesity that was initiated early in life - lasting through adulthood - could be more harmful to memory impairment and mood fluctuations such as depression. Results: Here we show that pre-pubertal male rats (30 days old) treated with a high-fat diet (40%) for 8-months gained ~50% more weight when compared to controls, exhibited depression and anxiety-like behaviors but no memory impairment. The prefrontal cortex of the obese rats exhibited an increase in the expression of genes related to inflammatory response, such as NFKb, MMP9, CCl2, PPARb, and PPARg. There were no alterations in genes known to be related to depression. Conclusion: Long-lasting obesity with onset in prepuberal age led to depression and neuroinflammation but not to memory impairment.

Casinga-cheirosa organic extract impairment over Balb-c male mice behavioral phenotype

ABSTRACT Laetia suaveolens (Poepp.) Benth., Salicaceae, popularly known as "casinga-cheirosa", "caferana", or "laranjinha", is native to Brazil but not endemic to this country. A crude organic extract was obtained from the leaves and stem and intraperitoneally administered in male Balb-c mice. Its behavioral effects were evaluated in the open field and elevated plus maze in a two-stage experiment that assessed ten different parameters related to behavior as locomotion, emotionality, and anxiety. In the first stage of the experiment, intraperitoneal the crude organic extract administration dose-dependently impaired locomotion and emotionality 30–120 min after administration. A significant decrease in defecation was observed, which was related to emotionality. No alterations in the elevated plus maze were found; thus, this apparatus was not used in the next stage of the experiment. In the second stage, the previously determined non-lethal dose of 0.1563 g/kg was intraperitoneally administered, which impaired locomotion and rearing frequency and increased immobility time. Necropsy revealed smooth intestine hemorrhage. Rutin, leucoside, nicotiflorin, guaijaverin, and astragalin were isolated from the crude organic extract. This is the first time that these compounds have been identified in L. suaveolens. In conclusion, the crude organic extract impaired locomotion and emotionality and caused hemorrhage in male Balb-c mice, indicating that its consumption can be harmful to humans and animals. The present results provide a basis for further studies on the pharmacology, toxicology, and natural product chemistry of the crude organic extract.

Neonatal lipopolysaccharide exposure induces sexually dimorphic sickness behavior in adult rats

The aim of the present study was to evaluate whether neonatal exposure to lipopolysaccharide (LPS; 50 µg/kg, i.p., on postnatal day 2) induces depressive- and/or anxiety-like effects and sexually dimorphic responses in rats challenged with LPS (100 µg/kg, i.p.) in adulthood. The results revealed that males presented a less depressive state in the forced swim test and exhibited no changes in general motor activity in the open field test. Females exhibited an increase in sickness behavior, revealing different behavioral strategies in response to a bacterial disease. The male rats also exhibited higher cell proliferation, reflected by bone marrow and peripheral blood counts, and female rats exhibited a decrease in corticosterone levels. No changes were observed in the elevated plus maze or peripheral cytokine levels (interleukin-1β and tumor necrosis factor-α). Neonatal exposure to LPS induced sexually dimorphic behavioral, neuroendocrine, and immune effects after an LPS challenge in adulthood, differentially affecting male and female susceptibility to disease later in life...

Influence of the intraperitoneal administration of antitumor Abarema auriculata extract on mice behavior

The organic extract EB689, obtained from the stem of Abarema auriculata (Benth.) Barneby & J.W.Grimes, Fabaceae, commonly known as "saboeiro-ferro", was chemically studied, as well as its influence over behavioral effects such as locomotion, emotionality and anxiety, after intra-peritonial administration were assessed. The open-field and elevated-plus maze were used in experiments divided into two stages. The first stage aimed for the identification of the main effects over behavior using a reduced number of animals against half-fold diluted doses of EB689. The same variables were also tested in a second stage of the experiment using the non-lethal intra-peritoneal dose of 4.8 mg/kg in a larger number of animals. It was observed that EB689 clearly decreased locomotion, which was probably caused by internal hemorrhage causing hypovolemic shock. Although it is the first time lupeol and eucryphin are described in A. auriculata, it is still not clear if they are involved in the toxicology of A. auriculata. The undesirable effects of EB689 are better understood, the basis for further pharmacological assays aiming antitumor activity are supported.

Sexual experience did not affect the long-term sexual behavior inhibition of male rats treated with fluoxetine

Antidepressants, including tricyclics, monoamine oxidase inhibitors and selective serotonin reuptake inhibitors cause sexual dysfunctions such as decreased sexual desire, erectile difficulties, and delayed ejaculation. Studies have shown that treatment with fluoxetine inhibits several components of sexual behavior in male rats. It is known that sexual experience improves the sexual behavior of male rats. Thus, the effects of sexual experience were examined in male rats during long-term treatment with fluoxetine or vehicle. Rats treated with 10mg/kg fluoxetine or vehicle daily (28 days) were observed for sexual behavior at the 14th, 21st, and 28th day of treatment. Long-term administration of fluoxetine increased the mount latency in control rats in the first session; no differences were observed in other parameters on the same day. Still in the control group, the mount and intromission latencies gradually decreased, whereas the number of intromissions and ejaculations increased over the sessions. The group in long-term treatment with fluoxetine also showed reduced mount and intromission latencies, although latencies remained significantly higher as compared to the control group. Fluoxetine-treated rats showed increased mount and intromission rates on the 28th day of treatment in relation to the first day. These data suggest that the impairment caused by long-term treatment with fluoxetine persists throughout the sessions despite the rats’ sexual experience.