Oral microbiota and Alzheimer's disease: Do all roads lead to Rome?

Alzheimer's disease (AD) is a progressive neurodegenerative pathology affecting milions of people worldwide associated with deposition of senile plaques. While the genetic and environmental risk factors associated with the onset and consolidation of late onset AD are heterogeneous and sporadic, growing evidence also suggests a potential link between some infectious diseases caused by oral microbiota and AD. Oral microbiota dysbiosis is purported to contribute either directly to amyloid protein production, or indirectly to neuroinflammation, occurring as a consequence of bacterial invasion. Over the last decade, the development of Human Oral Microbiome database (HOMD) has deepened our understanding of oral microbes and their different roles during the human lifetime. Oral pathogens mostly cause caries, periodontal disease, and edentulism in aged population, and, in particular, alterations of the oral microbiota causing chronic periodontal disease have been associated with the risk of AD. Here we describe how different alterations of the oral microbiota may be linked to AD, highlighting the importance of a good oral hygiene for the prevention of oral microbiota dysbiosis.

Aporphines and Parkinson's Disease: Medical Tools for the Future.

Parkinson's disease is a motor dysfunction that has been widely studied but many of the reports on commercial drugs for the treatment of this disease have afforded some undesirable side effects that generate an extensive and unviable treatment by economic costs and due to the bioavailability of the assayed compounds. At present, some molecules are used as L-DOPA agonists or can change the dopamine concentrations in the CNS. Thus, the use of aporphine-type alkaloids has given a real alternative due to the diverse natural sources where can be isolated or to obtain them by means of conventional syntheses. Isoquinoline alkaloids as liriodenine, phenanthrene-type alkaloids, alkoxy-hydroxyaporphine, aminothiazole-aporphine or lipoic ester aporphine derivatives are some of the examples to be considered in this mini-review, wherein the applied pharmacological effects to reduce the motor disorders and the possible medical properties of these alkaloids on the dopaminergic receptors are analyzed.