The hippocampus shrinks in late adulthood, leading to impaired memory and increased risk for dementia. Hippocampal and medial temporal lobe volumes are larger in higher-fit adults, and physical activity training increases hippocampal perfusion, but the extent to which aerobic exercise training can modify hippocampal volume in late adulthood remains unknown. Here we show, in a randomized controlled trial with 120 older adults, that aerobic exercise training increases the size of the anterior hippocampus, leading to improvements in spatial memory. Exercise training increased hippocampal volume by 2%, effectively reversing age-related loss in volume by 1 to 2 y. We also demonstrate that increased hippocampal volume is associated with greater serum levels of BDNF, a mediator of neurogenesis in the dentate gyrus. Hippocampal volume declined in the control group, but higher preintervention fitness partially attenuated the decline, suggesting that fitness protects against volume loss. Caudate nucleus and thalamus volumes were unaffected by the intervention. These theoretically important findings indicate that aerobic exercise training is effective at reversing hippocampal volume loss in late adulthood, which is accompanied by improved memory function.

https://www.pnas.org/content/pnas/108/7/3017.full.pdf

Exercise training increases size of hippocampus and improves memory

[Crohn's disease].

Quantitative autoradiographic mapping of serotonin receptors in the rat brain. I. Serotonin-1 receptors.

4 CLINICAL PARTICULARS 4.1 Therapeutic Indications Trimetazidine is indicated in adults as add-on therapy for the symptomatic treatment of patients with stable angina pectoris who are inadequately controlled by or intolerant to first-line antianginal therapies. 4.2 Posology and method of administration Oral administration. Posology The dose is one tablet of 35mg of trimetazidine twice daily during meals. Special populations Renal impairment In patients with moderate renal impairment (creatinine clearance [30-60] ml/min) (see sections 4.4 and 5.2), the recommended dose is 1 tablet of 35mg in the morning during breakfast. Elderly Elderly patients may have increased trimetazidine exposure due to age-related decrease in renal function (see section 5.2). In patients with moderate renal impairment (creatinine clearance [30-60] ml/min), the recommended dose is 1 tablet of 35mg in the morning during breakfast. Dose titration in elderly patients should be exercised with caution (see section 4.4). Health Products Regulatory Authority

Summary of product characteristics

The metabotropic glutamate receptors (mGluRs) are family C G-protein-coupled receptors that participate in the modulation of synaptic transmission and neuronal excitability throughout the central nervous system. The mGluRs bind glutamate within a large extracellular domain and transmit signals through the receptor protein to intracellular signaling partners. A great deal of progress has been made in determining the mechanisms by which mGluRs are activated, proteins with which they interact, and orthosteric and allosteric ligands that can modulate receptor activity. The widespread expression of mGluRs makes these receptors particularly attractive drug targets, and recent studies continue to validate the therapeutic utility of mGluR ligands in neurological and psychiatric disorders such as Alzheimer's disease, Parkinson's disease, anxiety, depression, and schizophrenia.

Metabotropic Glutamate Receptors: Physiology, Pharmacology, and Disease

Several lines of evidence suggest a crucial involvement of glutamate in the mechanism of action of anxiolytic and/or antidepressant drugs. The involvement of group I mGlu receptors in anxiety and depression has also been proposed. Given the recent discovery of a selective and brain penetrable mGlu5 receptor antagonists, the effect of 2-methyl-6-(phenylethynyl)-pyridine (MPEP), i.e. the most potent compound described, was evaluated in established models of anxiety and depression.




Experiments were performed on male Wistar rats or male Albino Swiss or C57BL/6J mice. The anxiolytic-like effects of MPEP was tested in the conflict drinking test and the elevated plus-maze test in rats as well as in the four-plate test in mice. The antidepressant-like effect was estimated using the tail suspension test in mice and the behavioural despair test in rats.




MPEP (1 – 30 mg kg−1) induced anxiolytic-like effects in the conflict drinking test and the elevated plus-maze test in rats as well as in the four-plate test in mice. MPEP had no effect on locomotor activity or motor coordination. MPEP (1 – 20 mg kg−1) did shorten the immobility time in a tail suspension test in mice, however it was inactive in the behavioural despair test in rats.




These data suggest that selective mGlu5 receptor antagonists may play a role in the therapy of anxiety and/or depression, further studies are required to identify the sites and the mechanism of action of MPEP.






British Journal of Pharmacology (2001) 132, 1423–1430; doi:10.1038/sj.bjp.0703923

/pdf/potential-anxiolytic-and-antidepressant-like-effects-of-mpep-3rpiorzvv5.pdf

Potential anxiolytic- and antidepressant-like effects of MPEP, a potent, selective and systemically active mGlu5 receptor antagonist.

It is believed that brain derived neurotrophic factor (BDNF) plays an important role in neuronal growth, transmission, modulation and plasticity. Single bout of exercise can increase plasma BDNF concentration [BDNF](p) in humans. It was recently reported however, that elevated [BDNF](p) positively correlated with risk factors for metabolic syndrome and type 2 diabetes mellitus in middle age group of subjects. On the other hand it is well established that endurance training decreases the risk of diabetes and development of metabolic syndrome. In the present study we have examined the effect of 5 weeks of moderate intensity endurance training on the basal and the exercise induced changes in [BDNF](p) in humans. Thirteen young, healthy and physically active men (mean +/- S.E: age 22.7 +/- 0.5 yr, body height 180.2 +/- 1.7 cm, body weight 77.0 +/- 2.5 kg, V(O2max) 45.29 +/- 0.93 ml x kg-1 x min(-1)) performed a five week endurance cycling training program, composed mainly of moderate intensity bouts. Before training [BDNF]p at rest have amounted to 10.3 +/- 1.4 pg x ml(-1). No effect of a single maximal incremental cycling up to V(O2max) on its concentration was found (10.9 +/- 2.3 pg x ml(-1), P=0.74). The training resulted in a significant (P=0.01) increase in [BDNF]p at rest to 16.8 +/- 2.1 pg x ml(-1), as well as in significant (P=0.0002) exercise induced increase in the [BDNF](p) (10.9 +/- 2.3 pg x ml(-1) before training vs. 68.4 +/- 16.0 pg x ml(-1) after training). The training induced increase in resting [BDNF](p) was accompanied by a slight decrease in insulin resistance (P=0.25), calculated using the homeostatic model assessment version 2 (HOMA2-IR), amounting to 1.40 +/- 0.13 before and 1.15 +/- 0.13 after the training. Moreover, we have found that the basal [BDNF](p) in athletes (n=16) was significantly higher than in untrained subjects (n=13) (29.5 +/- 9.5 pg x ml(-1) vs. 10.3 +/- 1.4 pg x ml(-1), P=0.013). We have concluded that endurance training of moderate intensity increases both basal as well as the end-exercise [BDNF](p) in young healthy men. This adaptive response, contrariwise to the recent findings in patients with metabolic disorders, was accompanied by a slight decrease in insulin resistance.

/pdf/endurance-training-increases-plasma-brain-derived-269fmbv8jo.pdf

Endurance training increases plasma brain-derived neurotrophic factor concentration in young healthy men

It is well documented that physical activity can induce a number of various stimuli which are able to enhance the strength and endurance performance of muscles. Moreover, regular physical activity can preserve or delay the appearance of several metabolic disorders in the human body. Physical exercise is also known to enhance the mood and cognitive functions of active people, although the physiological backgrounds of these effects remain unclear. In recent years, since the pioneering study in the past showed that physical activity increases the expression of the brain derived neurothophic factor (BDNF) in the rat brain, a number of studies were undertaken in order to establish the link between that neurothrophin and post-exercise enhancement of mood and cognitive functions in humans. It was recently demonstrated that physical exercise can increase plasma and/or serum BDNF concentration in humans. It was also reported that physical exercise or electrical stimulation can increase the BDNF expression in the skeletal muscles. In the present review, we report the current state of research concerning the effect of a single bout of exercise and training on the BDNF expression in the brain, in both the working muscles as well as on its concentrations in the blood. We have concluded that there may be potential benefits of the exercise-induced enhancement of the BDNF expression and release in the brain as well as in the peripheral tissues, resulting in the improvement of the functioning of the body, although this effect, especially in humans, requires more research.

/pdf/the-effect-of-physical-activity-on-the-brain-derived-71410sbi7t.pdf

The effect of physical activity on the brain derived neurotrophic factor: from animal to human studies.

Metabotropic glutamate receptor ligands as possible anxiolytic and antidepressant drugs

A growing body of evidence implicates a derangement of zinc homeostasis in mood disorders. In general, unipolar depression is connected with low blood zinc levels that are increased by effective antidepressant therapy. A placebo-controlled, double blind pilot study of zinc supplementation in antidepressant therapy was conducted in patients who fulfilled DSM IV criteria for major (unipolar) depression. Patients received zinc supplementation (6 patients; 25 mg of Zn2+ once daily) or placebo (8 patients) and were treated with standard antidepressant therapy (tricyclic antidepressants, selective serotonin reuptake inhibitors). Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI) were used to assess efficacy of antidepressant therapy, and patients' status was evaluated before the treatment and 2, 6 and 12 weeks after its commencement. Antidepressant treatment significantly reduced HDRS scores by the 2nd week of treatment in both groups, and lowered BDI scores at the 6th week in zinc-treated group. Zinc supplementation significantly reduced scores in both measures after 6- and 12-week supplementation when compared with placebo treatment. This preliminary study is the first demonstration of the benefit of zinc supplementation in antidepressant therapy. The mechanism(s) may be related to modulation of glutamatergic or immune systems by zinc ion.

/pdf/effect-of-zinc-supplementation-on-antidepressant-therapy-in-pczftccrj7.pdf

Andrzej Pilc

Papers

Potential anxiolytic- and antidepressant-like effects of MPEP, a potent, selective and systemically active mGlu5 receptor antagonist.

Endurance training increases plasma brain-derived neurotrophic factor concentration in young healthy men

The effect of physical activity on the brain derived neurotrophic factor: from animal to human studies.

Metabotropic glutamate receptor ligands as possible anxiolytic and antidepressant drugs

Effect of zinc supplementation on antidepressant therapy in unipolar depression: a preliminary placebo-controlled study.