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Alzheimer's disease (AD) is expected to affect more than 22 million people worldwide by 2025, causing devastating suffering and enormous costs to families and society. AD is a multifactorial disease, with a complex pathological mosaic. In rodents, AD-like dementia can be induced by cerebral microinjection of A[beta] peptide, leading to amyloid deposits, amnesia and various features of neurodegeneration. Marapuama (Ptychopetalum olacoides) is regarded as a 'brain tonic' in the Amazon region and shows a nootropic profile in rodents. AIM OF THE STUDY: Because a specific extract (POEE) of Marapuama was shown to possess promnesic and anti-amnesic properties, the aim of this study was to verify if POEE is also effective against A[beta](1-42)-induced cognitive deficit in mice. Additionally, A[beta] deposits (Congo red), GFAP immunoreactivity (immunohistochemistry), and neurodegenerative changes in the hippocampal pyramidal layer (Nissl) were examined as measures of A[beta](1-42)-induced neurodegeneration. MATERIALS AND METHODS: CF1 mice were subjected to the experimental Alzheimer model with the A[beta](1-42) i.c.v. administration. The effects of POEE 800mg/kg were evaluated over 14 consecutive days of treatment. RESULTS: The data show that 14 days of oral treatment with POEE (800mg/kg) was effective in preventing A[beta]-induced cognitive impairment, without altering the levels of BDNF and with parallel reductions in A[beta] deposits and astrogliosis. CA1 hippocampus loss induced by A[beta](1-42) was also diminished in POEE-treated mice. CONCLUSION: This study offers evidence of functional and neuroprotective effects of two weeks treatment with a Ptychopetalum olacoides extract against A[beta] peptide-induced neurotoxicity in mice. Given the multifactorial nature of neurodegeneration, the considerable potential for an AChE inhibitor displaying associated neuroprotective properties such as here reported warrants further clinic evaluation. [ABSTRACT FROM AUTHOR]

With the recognition that high levels of sustained stress are associated with the natural course of countless illnesses, effective anti-stress agents have gained importance. Improved endurance to particularly stressful periods is one of the medicinal claims for Marapuama (Ptychopetalum olacoides Bentham, PO), a popular Amazonian herbal. The purpose of this study was to evaluate if PO possesses anti-stress properties. To this end, an extract from PO (POEE) was evaluated on anxiety and glucose levels in mice submitted to the unpredictable chronic mild stress (UCMS) paradigm. POEE did not present anxiolytic effects, but was able to prevent (p<0.01) the UCMS-induced anxiety as assessed by the light/dark test (time spent in the lit area, POEE 100 and 300mg/kg 235.9+/-20.6s and 250.4+/-17.4s, respectively, compared to DMSO 104.7+/-24.4s). Likewise, although POEE did not induce noticeable effects on glycemia, it effectively (p<0.01) prevented the UCMS-induced hyperglycemia (POEE 100 and 300mg/kg 106.4+/-6.7mg/dl and 107.3+/-3.3mg/dl, respectively, compared to DMSO 134.6+/-5.9mg/dl). Additionally, POEE (50-200mg/kg i.p. and 800mg/kg p.o.) significantly (p<0.01 and p<0.05, respectively) increased the time to hypoxia-induced convulsion (by 38%, 51%, 59% and 27%, respectively for i.p. and p.o. treatments). The data indicate that POEE counteracts some of the effects brought about by chronic stress. This study combined with the identified antioxidant and neuroprotective properties, as well as the claimed benefits associated with stressful periods suggest that Ptychopetalum olacoides (Marapuama) might possess adaptogen-like properties. [ABSTRACT FROM AUTHOR]