Study of the Effects of L-tryptophane Nanoparticles on Motor Behavior in Alzheimer's Experimental Models.

BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease characterized by the progressive and incapacitating decay of cognitive, neuropsychiatric, and behavioral manifestations. L-tryptophan is the precursor amino acid of serotonin, which is a neurotransmitter responsible for mood balance and the sense of well-being and can be administered in the form of nanoparticles. OBJECTIVE: This study analyzed the effectiveness of L-tryptophan nanoparticles and L-tryptophan on behavioral physiological alterations resulting from AD in animal models. METHODS: The sample consisted of 50 Rattus norvegicus rats, divided in 10 groups with 5 animals each: one negative control (NC), three positive control groups (C3, C7, and C21), three groups treated with L-tryptophan nanoparticles (T3N, T7N, and T21N) at the concentration of 1.5 mg, and three groups treated with L-tryptophan (T3L, T7L, and T21L) at the concentration of 1.5 mg. The rats underwent stereotactic surgery to induce AD through the injection of amyloid beta-amyloid peptide1-42 in the intracerebroventricular region. All rats were submitted to pre- and post-surgery and post-treatment motor behavior evaluation through the Later Water Maze (LWM) and elevated cross-labyrinth (ECL). Histological analysis was performed to verify the presence of senile plaques, and the statistical analysis used the unpaired T-test. RESULTS: Significant intergroup differences were observed in some of the evaluated parameters between treated and untreated groups. CONCLUSION: It was concluded that the treatment with L-tryptophan nanoparticles was beneficial to improve behavioral reactions in the Alzheimer's model.

Formulation, characterization, and in vitro/in vivo studies of capsaicin-loaded albumin nanoparticles.

Capsaicin (CAP) is a secondary metabolite with high therapeutic potential. It displays several bioactive properties including hypolipidemic, antioxidant, anti-inflammatory and analgesic effects. However, CAP presents toxicity to healthy cells and poor pharmacokinetic profile, which is characterized by toxic metabolites and short half-life. In this study, CAP-loaded albumin nanoparticles were obtained by the desolvation-coacervation method. The preparation process was optimized by the application of a factorial design. Nanoparticles presented diameter of about 200 nm, quasi-spherical morphology, encapsulation efficiency of 98.3 ±â€¯7.4%, and negative zeta potential. The in vitro release assay demonstrated a biphasic profile, characterized by a fast release over 12 h followed by a prolonged release rate. Nanoencapsulated CAP showed significant antioxidant activity in an in vitro assay which was concentration - and time-dependent. In addition, the in vivo study demonstrated for the first time that both free and nanoencapsulated drug reduced TNF-alpha concentrations in the absence of inflammatory stimuli model. These novel findings indicate that albumin nanoparticles are potential CAP carriers and that this new drug formulation may be useful in several conditions, including cancer, inflammation, and neuropathic pain.

The effects of transcranial LED therapy (TCLT) on cerebral blood flow in the elderly women.

During aging processes, there is a range of functional changes, where we can highlight the disease related to the central nervous system, such as Alzheimer disease and others forms of dementia. This study investigated the effects of transcranial light emitting diode (LED) on cerebral blood flow in healthy elderly women analyzed by transcranial Doppler ultrasound (TCD) of the right and left middle cerebral artery and basilar artery. Twenty-five noninstitutionalized elderly women (mean age 72 years old), with a cognitive status >24, were assessed using transcranial Doppler ultrasound on two separate occasions: pre-irradiation and post-transcranial LED therapy (TCLT). Prior to this, they answered two questionnaires: the perceived stress scale and the general health questionnaire. TCLT (627 nm, 70 mW/cm(2), 10 J/cm(2)) was performed at four points of the frontal and parietal region for 30 s each, totaling 120 s two times per week for 4 weeks. Paired t-test results showed that there was a significant improvement after TCLT with increase in the systolic and diastolic velocity of the left middle cerebral artery (25 and 30%, respectively) and basilar artery (up to 17 and 25%), as well as a decrease in the pulsatility index and resistance index values of the three cerebral arteries analyzed (p < 0.05). TCD parameters showed improvement in the blood flow on the arteries analyzed. TCLT promoted a blood and vasomotor behavior of the basilar and middle cerebral arteries in healthy elderly women.

Macro and microscopic analysis of island skin grafts after low-level laser therapy.

OBJECTIVE: To observe the effects of low intensity laser therapy in inflammation, wound healing and epithelialization of island skin grafts. METHODS: Twenty rats were subjected to this grafting technique and divided subsequently into two equal groups, one treated with laser and the other control. RESULTS: there was less inflammation, faster healing, epithelialization and keratinization in the laser-treated animals when compared to the untreated. CONCLUSION: Low intensity laser therapy is helpful to island skin grafting.

Análises macro e microscópicas de enxertos cutâneos por semeadura após laserterapia de baixa intensidade / Macro and microscopic analysis of island skin grafts after low-level laser therapy

OBJETIVO: observar se a laserterapia de baixa intensidade acelera o processo inflamatório, a cicatrização e epitelização de enxertos cutâneos por semeadura. MÉTODOS: vinte ratos foram submetidos a esta técnica de enxertia e divididos em dois grupos iguais, um tratado com laser e outro controle. RESULTADOS: houve menor tempo de reação inflamatória, maior velocidade de cicatrização, epitelização e queratinização nos animais tratados com laser em relação aos não tratados. CONCLUSÃO: a laserterapia de baixa intensidade é efetiva no auxílio ao tratamento de enxertos por semeadura.

OBJECTIVE: To observe the effects of low intensity laser therapy in inflammation, wound healing and epithelialization of island skin grafts. METHODS: Twenty rats were subjected to this grafting technique and divided subsequently into two equal groups, one treated with laser and the other control. RESULTS: there was less inflammation, faster healing, epithelialization and keratinization in the laser-treated animals when compared to the untreated. CONCLUSION: Low intensity laser therapy is helpful to island skin grafting.