Glutamate, Glutamine, GABA and Oxidative Products in the Pons Following Cortical Injury and Their Role in Motor Functional Recovery.

Brain injury leads to an excitatory phase followed by an inhibitory phase in the brain. The clinical sequelae caused by cerebral injury seem to be a response to remote functional inhibition of cerebral nuclei located far from the motor cortex but anatomically related to the injury site. It appears that such functional inhibition is mediated by an increase in lipid peroxidation (LP). To test this hypothesis, we report data from 80 rats that were allocated to the following groups: the sham group (n = 40), in which rats received an intracortical infusion of artificial cerebrospinal fluid (CSF); the injury group (n = 20), in which rats received CSF containing ferrous chloride (FeCl2, 50 mM); and the recovery group (n = 20), in which rats were injured and allowed to recover. Beam-walking, sensorimotor and spontaneous motor activity tests were performed to evaluate motor performance after injury. Lipid fluorescent products (LFPs) were measured in the pons. The total pontine contents of glutamate (GLU), glutamine (GLN) and gamma-aminobutyric acid (GABA) were also measured. In injured rats, the motor deficits, LFPs and total GABA and GLN contents in the pons were increased, while the GLU level was decreased. In contrast, in recovering rats, none of the studied variables were significantly different from those in sham rats. Thus, motor impairment after cortical injury seems to be mediated by an inhibitory pontine response, and functional recovery may result from a pontine restoration of the GLN-GLU-GABA cycle, while LP may be a primary mechanism leading to remote pontine inhibition after cortical injury.

Sensorimotor Intervention Recovers Noradrenaline Content in the Dentate Gyrus of Cortical Injured Rats.

Nowadays, a consensus has been reached that designates the functional and structural reorganization of synapses as the primary mechanisms underlying the process of recovery from brain injury. We have reported that pontine noradrenaline (NA) is increased in animals after cortical ablation (CA). The aim of the present study was to explore the noradrenergic and morphological response after sensorimotor intervention (SMI) in rats injured in the motor cortex. We used male Wistar adult rats allocated in four conditions: sham-operated, injured by cortical ablation, sham-operated with SMI and injured by cortical ablation with SMI. Motor and somatosensory performance was evaluated prior to and 20 days after surgery. During the intervening period, a 15-session, SMI program was implemented. Subsequently, total NA analysis in the pons and dentate gyrus (DG) was performed. All groups underwent histological analysis. Our results showed that NA content in the DG was reduced in the injured group versus control, and this reduction was reverted in the injured group that underwent SMI. Moreover, injured rats showed reduction in the number of granule cells in the DG and decreased dentate granule cell layer thickness. Notably, after SMI, the loss of granule cells was reverted. Locus coeruleus showed turgid cells in the injured rats. These results suggest that SMI elicits biochemical and structural modifications in the hippocampus that could reorganize the system and lead the recovery process, modulating structural and functional plasticity.

Alpha2-adrenergic receptor activation reinstates motor deficits in rats recovering from cortical injury.

Norepinephrine plays an important role in motor functional recovery after a brain injury caused by ferrous chloride. Inhibition of norepinephrine release by clonidine is correlated with motor deficits after motor cortex injury. The aim of this study was to analyze the role of α2-adrenergic receptors in the restoration of motor deficits in recovering rats after brain damage. The rats were randomly assigned to the sham and injury groups and then treated with the following pharmacological agents at 3 hours before and 8 hours, 3 days, and 20 days after ferrous chloride-induced cortical injury: saline, clonidine, efaroxan (a selective antagonist of α2-adrenergic receptors) and clonidine + efaroxan. The sensorimotor score, the immunohistochemical staining for α2A-adrenergic receptors, and norepinephrine levels were evaluated. Eight hours post-injury, the sensorimotor score and norepinephrine levels in the locus coeruleus of the injured rats decreased, and these effects were maintained 3 days post-injury. However, 20 days later, clonidine administration diminished norepinephrine levels in the pons compared with the sham group. This effect was accompanied by sensorimotor deficits. These effects were blocked by efaroxan. In conclusion, an increase in α2-adrenergic receptor levels was observed after injury. Clonidine restores motor deficits in rats recovering from cortical injury, an effect that was prevented by efaroxan. The underlying mechanisms involve the stimulation of hypersensitive α2-adrenergic receptors and inhibition of norepinephrine activity in the locus coeruleus. The results of this study suggest that α2 receptor agonists might restore deficits or impede rehabilitation in patients with brain injury, and therefore pharmacological therapies need to be prescribed cautiously to these patients.

Elaboración de gel y shampoo para el control de las manifestaciones clínicas de la caspa (Dermatitis Seborreica) elaborado a partir de extracto de jengibre (Zingiber officinale): Estudio piloto / Preparation of gel and shampoo for the control of clinical manifestations of dandruff (Seborrheic Dermatitis) made from ginger extract (Zingiber officinale): Pilot study

La investigación se realizó con el fin de evaluar la utilización del rizoma de jengibre (Zingiber officinale) para la prevención de la aparición de caspa en el cuero cabelludo; comprobando si existe una diferencia en la actividad antifúngica si se elabora el cosmético a base del parénquima o a base de la corteza. De este modo, aprovechar el uso completo de la raíz de jengibre; lo que contribuye a un menor costo económico para la industria cosmética. Para ello, se realizaron los ensayos microbiológicos correspondientes para su uso seguro en humanos, según lo que indica la norma RTCA 71.03.45:07 para productos cosméticos. Así mismo, se efectuaron las pruebas organolépticas y físicoquímicas a los productos preparados, las características para el shampoo a base de polvo de jengibre fueron: apariencia líquida, color amarillo, olor característico a jengibre y consistencia homogénea, se obtuvo un pH de 5.5, viscosidad de 3400 cps, la calidad de la espuma era cerrada y de 6 mm. En el caso del gel a base de polvo de jengibre, obtuvo apariencia viscosa, color amarillo, olor característico a jengibre y consistencia homogénea, para este producto se obtuvo un pH de 6.9 y una viscosidad de 6360 cps. Para evaluar la propiedad antifúngica del gel y shampoo, se efectuó un estudio de un mes. Se formaron 4 grupos (cada grupo de 8 voluntarios de sexo masculino), a los que se les proporcionó el producto: gel a base de parénquima, gel a base de corteza, shampoo a base de parénquima o shampoo a base de corteza de jengibre. Se ejecutaron las evaluaciones semanalmente a partir de su inicio, para esto se llevó un control iconográfico de cada paciente y un Scotch Tape test para evaluar la presencia del hongo Pityrosporum ovale en su forma activa e inactiva. Los datos fueron evaluados a partir de estadística descriptiva, por lo cual, se obtuvo que el gel es el mejor vehículo para el tratamiento contra la caspa, ya que se alcanzó el 12.5 % de control total de las manifestaciones (microbiológicas y clínicas) en pacientes de este grupo, ningún paciente presentó control total de las manifestaciones (microbiológicas y clínicas) de los que utilizaron el shampoo. Además, se presentó el 31.25% de control de manifestaciones microbiológicas y el 18.75% en control de las manifestaciones clínicas en pacientes que utilizaron gel a base de jengibre, mientras que en pacientes que utilizaron shampoo a base de jengibre, el 12.50% adquirió control de las manifestaciones clínicas y el 18.75% presentó control de las manifestaciones microbiológicas.