Association of whole mtDNA, an NADPH G11914A variant, and haplogroups with high physical performance in an elite military troop.

Physical performance is a multifactorial and complex trait influenced by environmental and hereditary factors. Environmental factors alone have been insufficient to characterize all outstanding phenotypes. Recent advances in genomic technologies have enabled the investigation of whole nuclear and mitochondrial genome sequences, increasing our ability to understand interindividual variability in physical performance. Our objective was to evaluate the association of mitochondrial polymorphic loci with physical performance in Brazilian elite military personnel. Eighty-eight male military personnel who participated in the Command Actions Course of the Army were selected. Total DNA was obtained from blood samples and a complete mitochondrial genome (mtDNA) was sequenced using Illumina MiSeq platform. Twenty-nine subjects completed the training program (FINISHED, 'F'), and fifty-nine failed to complete (NOT_FINISHED, 'NF'). The mtDNA from NF was slightly more similar to genomes from African countries frequently related to endurance level. Twenty-two distinct mtDNA haplogroups were identified corroborating the intense genetic admixture of the Brazilian population, but their distribution was similar between the two groups (FST=0.0009). Of 745 polymorphisms detected in the mtDNA, the position G11914A within the NADPH gene component of the electron transport chain, was statistically different between F and NF groups (P=0.011; OR: 4.286; 95%CI: 1.198-16.719), with a higher frequency of the G allele in group F individuals). The high performance of military personnel may be mediated by performance-related genomic traits. Thus, mitochondrial genetic markers such as the ND4 gene may play an important role on physical performance variability.

Association of whole mtDNA, an NADPH G11914A variant, and haplogroups with high physical performance in an elite military troop

Physical performance is a multifactorial and complex trait influenced by environmental and hereditary factors. Environmental factors alone have been insufficient to characterize all outstanding phenotypes. Recent advances in genomic technologies have enabled the investigation of whole nuclear and mitochondrial genome sequences, increasing our ability to understand interindividual variability in physical performance. Our objective was to evaluate the association of mitochondrial polymorphic loci with physical performance in Brazilian elite military personnel. Eighty-eight male military personnel who participated in the Command Actions Course of the Army were selected. Total DNA was obtained from blood samples and a complete mitochondrial genome (mtDNA) was sequenced using Illumina MiSeq platform. Twenty-nine subjects completed the training program (FINISHED, 'F'), and fifty-nine failed to complete (NOT_FINISHED, 'NF'). The mtDNA from NF was slightly more similar to genomes from African countries frequently related to endurance level. Twenty-two distinct mtDNA haplogroups were identified corroborating the intense genetic admixture of the Brazilian population, but their distribution was similar between the two groups (FST=0.0009). Of 745 polymorphisms detected in the mtDNA, the position G11914A within the NADPH gene component of the electron transport chain, was statistically different between F and NF groups (P=0.011; OR: 4.286; 95%CI: 1.198-16.719), with a higher frequency of the G allele in group F individuals). The high performance of military personnel may be mediated by performance-related genomic traits. Thus, mitochondrial genetic markers such as the ND4 gene may play an important role on physical performance variability.

Effect of tryptamine antagonists on self-stimulation. Interaction with amphetamine.

In order to investigate the role played by serotonergic mechanisms in self-stimulation (SS) behavior, the effects of two tryptamine antagonists, cyproheptadine and methysergide on SS were measured. Also the influence of antitryptaminic drug pre-treatment on the facilitatory effect of amphetamine, a pro-adrenergic drug, on SS was studied. Rats with brain electrodes permanently implanted at the lateral hypothalamus and trained to lever-press for response-contingent brain electric stimulus presentation were used. Stimulus current was maintained at threshold level. Both tryptamine antagonists used potentiated the enhancing effect of amphetamine on low SS rates, displacing to the left its dose-effect curve; cyproheptadine was at least three times more potent than methysergide. In addition, cyproheptadine, but not methysergide, caused dose-related increases in SS rate, when given alone. These results suggest that brain serotonergic systems play an inhibitory role in SS, opposing the facilitatory influence of adrenergic mechanisms.

Reversal of the increase in apomorphine-induced stereotypy and aggression in REM sleep deprived rats by dopamine agonist pretreatments.

REM sleep deprivation (REMSD) induces augmented responses to dopaminergic agonists. Prolonged administration of neuroleptics induces a similar state, probably by the production of supersensitivity of dopaminergic receptors. Such a supersensitive state could be induced by REMSD as a result of impairment of dopamine neurotransmission. In order to test this hypothesis, bromocriptine, nomifensine, amphetamine, L-dopa, imipramine and electroconvulsive shock (ECS) were administered to rats during REMSD, and aggressive and stereotyped behaviors were measured. Amphetamine and L-dopa pretreatment attenuated the increases in apomorphine-induced stereotypy and aggression in REMSD rats, but ECS selectively reduced apomorphine-induced aggression. The other drugs tested were ineffective on both behavioral tests. Such a selective action may reflect different effects of ECS on different dopaminergic systems such as those involved with stereotypy and aggression. The results suggest that REMSD induces an increase in dopaminergic sensitivity which may be reversed by pretreatment with some dopaminergic agonists.

Antiulcerogenic effects of two Maytenus species in laboratory animals.

Leaves of Maytenus species are commonly used in Brazil for the treatment of gastric ulcers, dyspepsias and other gastric problems. The present study evaluated the antiulcerogenic potential of a boiling water extract of equal parts of M. aquifolium and M. ilicifolia leaves against ulcer lesions induced by indomethacin and cold-restraint stress in rats. Ranitidine and cimetidine were used as reference drugs. The oral and intraperitoneal administration of the extract had a potent antiulcerogenic effect against both types of ulcers. The extract was shown to cause an increase in volume and pH of gastric juice of the animals with the pH effects comparable to those of cimetidine. The results tend to confirm the popular use of the plant.

Pharmacology of lemongrass (Cymbopogon citratus Stapf). I. Effects of teas prepared from the leaves on laboratory animals.

Cymbopogon citratus is one of the most used plants in Brazilian folk medicine for the treatment of nervous and gastrointestinal disturbances. It is also used in many other places to treat feverish conditions. The usual way to use it is by ingesting an infusion made by pouring boiling water on fresh or dried leaves (which is called "abafado" in Portuguese). Abafados obtained from lemongrass harvested in three different areas of Brazil (Ceará, Minas Gerais and São Paulo States) were tested on rats and mice in an attempt to add experimental confirmation to its popular medicinal use. Citral, the main constituent of the essential oil in Brazilian lemongrass, was also studied for comparison. Oral doses of abafados up to 40 times (C40) larger than the corresponding dosage taken by humans, or of 200 mg/kg of citral, were unable to decrease body temperature of normal rats and/or rats made hyperthermic by previous administration of pyrogen. However, both compounds acted when injected by intraperitoneal route. Oral administration of doses C20 -C100 of abafados and 200 mg/kg of citral did not change the intestinal transit of a charcoal meal in mice, nor did it decrease the defecation scores of rats in an open-field arena. Again, by intraperitoneal route both compounds were active. The possible central nervous system depressant effect of the abafados was investigated by using batteries of 12 tests designed to detect general depressant, hypnotic, neuroleptic, anticonvulsant and anxiolytic effects. In all the tests employed, oral doses of abafados up to C208 or of citral up to 200 mg/kg were without effect. Only in a few instances did intraperitoneal doses demonstrate effects. These data do no lend support to the popular oral therapeutic use of lemongrass to treat nervous and intestinal ailments and feverish conditions.