Autonomic nervous system in the control of energy balance and body weight: personal contributions.

The prevalence of obesity is increasing in the industrialized world, so that the World Health Organization considers obesity as a "pandemia" in rich populations. The autonomic nervous system plays a crucial role in the control of energy balance and body weight. This review summarizes our own data and perspectives, emphasizing the influence exerted by autonomic nervous system on energy expenditure and food intake, which are able to determine the body weight. Activation of the sympathetic discharge causes an increase in energy expenditure and a decrease in food intake, while reduction of food intake and body weight loss determines a reduction of the sympathetic activity. On the other hand, pathophysiological mechanisms of the obesity involve alterations of the sympathetic nervous system in accordance with the "Mona Lisa Hypothesis," an acronym for "most obesities known are low in sympathetic activity." Furthermore, the parasympathetic influences on the energy expenditure are analyzed in this review, showing that an increase in parasympathetic activity can induce a paradoxical enhancement of energy consumption.

Espresso coffee increases parasympathetic activity in young, healthy people.

Caffeine induces modifications of activity of the autonomic nervous system. This study analyzed the effect of a cup of espresso coffee on the heart rate variability (HRV) power spectral analysis, which is a method providing evaluation of the sympathetic and parasympathetic discharge. In young, healthy sedentary subjects (10 male, 10 female; aged 25-30 years), the HRV-power spectrum was evaluated over a period of 150 min after the administration of espresso coffee (caffeine, 75 mg) or decaffeinated coffee (caffeine, < 18 mg) in supine and seated position. Absolute values of the spectrum were summed in low (LF) and high frequencies (HF). The LF and HF spectra were used to estimate the sympathetic and parasympathetic activity, respectively. In the supine position, coffee increases HF, while decaffeinated coffee causes little modifications of HF. In the seated position, HF is not modified by coffee or decaffeinated coffee. Coffee and decaffeinated coffee do not induce any modification of LF in both positions. This experiment indicates that espresso coffee influences parasympathetic activity in the supine position.

Galactosilated dopamine increases attention without reducing activity in C57BL/6 mice.

Different strategies can be used to carry dopamine into the brain such as L-Dopa precursors or galactosilated form of DA (GAL-DA). The aim of this study was to investigate whether GAL-DA would reduce hyperactivity and increase non-selective attention (NSA) in a mouse model of attention deficit hyperactivity disorder (ADHD), as, i.e. C57BL/6 as did in NHE rats. Here we report that GAL-DA increases NSA in a spatial novelty in C57BL/6 mice. They received a single i.p. injection of GAL-DA (10 mg/kg or 100 mg/kg) or equimolar galactose vehicle. Another mouse strain the Swiss albino was introduced as inbred control group. Three hours after last injection mice were tested in a Làt-maze for 30-min. Behaviour was analyzed for horizontal (traveled distance) and vertical activity (orienting frequency and scanning durations) which shares cognitive and non-cognitive nature, respectively. Ten milligram per kilograms of GAL-DA, increases scanning duration in C57BL/6 mice. Thus a low dose of GAL-DA increases NSA without reducing hyperactivity in this mouse model of ADHD.