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PubMed2006

PPAR: a new pharmacological target for neuroprotection in stroke and neurodegenerative diseases.

PPARs (peroxisome-proliferator-activated receptors) are ligand-activated transcriptional factor receptors belonging to the so-called nuclear receptor family. The three isoforms of PPAR (alpha, beta/delta and gamma) are involved in regulation of lipid or glucose metabolism. Beyond metabolic effects, PPARalpha and PPARgamma activation also induces anti-inflammatory and antioxidant effects in different organs. These pleiotropic effects explain why PPARalpha or PPARgamma activation has been tested as a neuroprotective agent in cerebral ischaemia. Fibrates and other non-fibrate PPARalpha activators as well as thiazolidinediones and other non-thiazolidinedione PPARgamma agonists have been demonstrated to induce both preventive and acute neuroprotection. This neuroprotective effect involves both cerebral and vascular mechanisms. PPAR activation induces a decrease in neuronal death by prevention of oxidative or inflammatory mechanisms implicated in cerebral injury. PPARalpha activation induces also a vascular protection as demonstrated by prevention of post-ischaemic endothelial dysfunction. These vascular effects result from a decrease in oxidative stress and prevention of adhesion proteins, such as vascular cell adhesion molecule 1 or intercellular cell-adhesion molecule 1. Moreover, PPAR activation might be able to induce neurorepair and endothelium regeneration. Beyond neuroprotection in cerebral ischaemia, PPARs are also pertinent pharmacological targets to induce neuroprotection in chronic neurodegenerative diseases.

Brain↗

PubMed2002

[Systemic sclerosis and pregnancy].

PURPOSE: Pregnancy in a patient with systemic sclerosis (SSc) may pose a double problem to the medical team: influence of SSc on pregnancy and consequences of pregnancy to SSc manifestations. CURRENT KNOWLEDGE AND KEY POINTS: Concepts have evolved. SSc was considered for a long time not only as not very propitious for pregnancy but also as a strict contraindication for procreation because risks for the mother and the baby were thought to be major. Currently, fertility is thought to be normal. Miscarriages and small-for-gestation age infants rate do not seem to be higher in SSc. Maternal and perinatal mortality is also not higher in SSc without severe visceral manifestations, i.e. without either pulmonary hypertension, or cardiac or respiratory insufficiency. Conversely, there is a significantly higher frequency of premature infants in SSc. As regards influence of pregnancy on SSc, the greatest fear is the occurrence of renal crisis, which may be life threatening for both mother and child. Each elevation of blood pressure, even if this increase is mild, should be considered as potentially very serious. However, pregnancy itself does not seem to increase the risk of renal crisis. Consequences of pregnancy to SSc manifestations are various but usually mild. FUTURE PROSPECTS AND PROJECTS: SSc is not a strict contraindication for pregnancy only if severe organ involvement, diffuse subset of SSc or recent onset of the disease has been ruled out. Physicians should be aware of specific problems, which SSc is possibly posing during pregnancy. Finally, it has been recently suggested that pregnancies could be involved in the pathogenesis of SSc through persisting microchimerism of fetal origin.

Acute Disease↗