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Alterations in the structure, function, and microcirculation of the thalamus, a key brain region involved in pain pathways, have previously been demonstrated in patients with painless and painful diabetic peripheral neuropathy (DPN). However, thalamic neurotransmitter levels including γ-aminobutyric acid (GABA) (inhibitory neurotransmitter) and glutamate (excitatory neurotransmitter) in different DPN phenotypes are not known. We performed a magnetic resonance spectroscopy study and quantified GABA and glutamate levels within the thalamus, in a carefully characterized cohort of participants with painless and painful DPN. Participants with DPN (painful and painless combined) had a significantly lower GABA:H2O ratio compared with those without DPN (healthy volunteers [HV] and participants with diabetes without DPN [no DPN]). Participants with painless DPN had the lowest GABA:H2O ratio, which reached significance compared with HV and no DPN, but not painful DPN. There was no difference in GABA:H2O in painful DPN compared with all other groups. A significant correlation with GABA:H2O and neuropathy severity was also seen. This study demonstrates that lower levels of thalamic GABA in participants with painless DPN may reflect neuroplasticity due to reduced afferent pain impulses, whereas partially preserved levels of GABA in painful DPN may indicate that central GABAergic pathways are involved in the mechanisms of neuropathic pain in diabetes. Article Highlights: The thalamus has been shown to play a key role in the cerebral mechanisms of diabetic peripheral neuropathy (DPN), but neurotransmitter levels have not been explored. We sought to determine the levels of excitatory (glutamate) and inhibitory (γ-aminobutyric acid [GABA]) neurotransmitter levels in the thalamus in participants with painful and painless DPN. Thalamic GABA levels were reduced in participants with painless DPN, with partially preserved levels seen in painful DPN. Alterations of thalamic GABAergic pathways could be involved in the central mechanisms of both painful and painless DPN. [ABSTRACT FROM AUTHOR]

BackgroundAnxiety and depression are common psychological comorbidities that impact the quality of life (QoL) of patients. In this systematic review, we 1) determined the impact of anxiety and depression on outcomes in patients with osteoarthritis (OA) and 2) summarized unique challenges these comorbidities present to current OA management.Patients and methodsA systematic literature search was performed using the OVID Medline and EMBASE databases until April 2016. Full-text research articles published in English from the year 2000 onward with a sample size of >100 were included in this review. Eligible research articles were reviewed and the following data were extracted: study author(s), year of publication, study design, and key findings.ResultsA total of 38 studies were included in the present review. The present study found that both anxiety and/or depression were highly prevalent among patients with OA. Patients with OA diagnosed with these comorbidities experienced more pain, had frequent hospital visits, took more medication, and reported less optimal outcomes. Management strategies in the form of self-care, telephone support, audio/video education programs, and new pharmacotherapies were reported with favorable results.ConclusionAnxiety and depression adversely impact the QoL of patients with OA. Physicians/caregivers are highly recommended to consider these comorbidities in patients with OA. Ultimately, a holistic individualized management approach is necessary to improve patient outcomes.

Maladaptive wound healing responses to chronic tissue injury result in organ fibrosis. Fibrosis, which entails excessive extracellular matrix (ECM) deposition and tissue remodeling by activated myofibroblasts, leads to loss of proper tissue architecture and organ function; however, the molecular mediators of myofibroblast activation have yet to be fully identified. Here we identify soluble ephrin-B2 (sEphrin-B2) as a new profibrotic mediator in lung and skin fibrosis. We provide molecular, functional and translational evidence that the ectodomain of membrane-bound ephrin-B2 is shed from fibroblasts into the alveolar airspace after lung injury. Shedding of sEphrin-B2 promotes fibroblast chemotaxis and activation via EphB3 and/or EphB4 receptor signaling. We found that mice lacking ephrin-B2 in fibroblasts are protected from skin and lung fibrosis and that a disintegrin and metalloproteinase 10 (ADAM10) is the major ephrin-B2 sheddase in fibroblasts. ADAM10 expression is increased by transforming growth factor (TGF)-[beta]1, and ADAM10-mediated sEphrin-B2 generation is required for TGF-[beta]1-induced myofibroblast activation. Pharmacological inhibition of ADAM10 reduces sEphrin-B2 levels in bronchoalveolar lavage and prevents lung fibrosis in mice. Consistent with the mouse data, ADAM10-sEphrin-B2 signaling is upregulated in fibroblasts from human subjects with idiopathic pulmonary fibrosis. These results uncover a new molecular mechanism of tissue fibrogenesis and identify sEphrin-B2, its receptors EphB3 and EphB4 and ADAM10 as potential therapeutic targets in the treatment of fibrotic diseases., Author(s): David Lagares (corresponding author) [1]; Parisa Ghassemi-Kakroodi [2]; Caroline Tremblay [2]; Alba Santos [1]; Clemens K Probst [1]; Alicia Franklin [1]; Daniela M Santos [1]; Paula Grasberger [1]; Neil [...]