Hyperbaric oxygen therapy ameliorates pathophysiology of 3xTg-AD mouse model by attenuating neuroinflammation.

There is a real need for new interventions for Alzheimer's disease (AD). Hyperbaric oxygen therapy (HBOT), the medical administration of 100% oxygen at conditions greater than 1 atmosphere absolute, has been used successfully to treat several neurological conditions, but its effects on AD pathology have never been thoroughly examined. Therefore, we exposed old triple-transgenic (3xTg) and non-transgenic mice to HBOT followed by behavioral, histological, and biochemical analyses. HBOT attenuated neuroinflammatory processes by reducing astrogliosis, microgliosis, and the secretion of proinflammatory cytokines (IL-1ß and TNFα) and increasing expression of scavenger receptor A, arginase1, and antiinflammatory cytokines (IL-4 and IL-10). Moreover, HBOT reduced hypoxia, amyloid burden, and tau phosphorylation in 3xTg mice and ameliorated their behavioral deficits. Therefore, we suggest that HBOT has multifaceted effects that reduce AD pathologies, even in old mice. Given that HBOT is used in the clinic to treat various indications, including neurological conditions, these results suggest HBOT as a novel therapeutic intervention for AD.

Low-level laser therapy ameliorates disease progression in a mouse model of Alzheimer's disease.

Low-level laser therapy (LLLT) has been used to treat inflammation, tissue healing, and repair processes. We recently reported that LLLT to the bone marrow (BM) led to proliferation of mesenchymal stem cells (MSCs) and their homing in the ischemic heart suggesting its role in regenerative medicine. The aim of the present study was to investigate the ability of LLLT to stimulate MSCs of autologous BM in order to affect neurological behavior and ß-amyloid burden in progressive stages of Alzheimer's disease (AD) mouse model. MSCs from wild-type mice stimulated with LLLT showed to increase their ability to maturate towards a monocyte lineage and to increase phagocytosis activity towards soluble amyloid beta (Aß). Furthermore, weekly LLLT to BM of AD mice for 2 months, starting at 4 months of age (progressive stage of AD), improved cognitive capacity and spatial learning, as compared to sham-treated AD mice. Histology revealed a significant reduction in Aß brain burden. Our results suggest the use of LLLT as a therapeutic application in progressive stages of AD and imply its role in mediating MSC therapy in brain amyloidogenic diseases.

Toll-like receptors expression and signaling in glia cells in neuro-amyloidogenic diseases: towards future therapeutic application.

Toll-like receptors (TLRs) are known to be expressed by innate immune response cells and to play a critical role in their activation against foreign pathogens. It was recently suggested that TLRs have an important role in the crosstalk between neurons and glial cells in the central nervous system (CNS). TLR signaling was reported to be associated with a yin-yang effect in the CNS. While TLR signaling was linked to neurogenesis, it was also found to be involved in the pathogenesis of neurodegenerative diseases. This paper will focus on TLR signaling in glial cells in neurodegenerative diseases such as Alzheimer's disease, prion diseases, amyotrophic lateral sclerosis, and Parkinson's disease. Understanding the pattern of TLR signaling in the glial cells may lead to the identification of new targets for therapeutic application.