Effects of metyrapone and dexamethasone upon pro-gamma-MSH plasma levels in depressed patients and healthy controls

Molecular Mechanisms and Therapeutics for the GAA·TTC Expansion Disease Friedreich Ataxia

Friedreich ataxia (FRDA), the most common inherited ataxia, is caused by transcriptional silencing of the nuclear FXN gene, encoding the essential mitochondrial protein frataxin. Currently, there is no approved therapy for this fatal disorder. Gene silencing in FRDA is due to hyperexpansion of the triplet repeat sequence GAA·TTC in the first intron of the FXN gene, which results in chromatin histone modifications consistent with heterochromatin formation. Frataxin is involved in mitochondrial iron homeostasis and the assembly and transfer of iron-sulfur clusters to various mitochondrial enzymes and components of the electron transport chain. Frataxin insufficiency leads to progressive spinocerebellar neurodegeneration, causing symptoms of gait and limb ataxia, slurred speech, muscle weakness, sensory loss, and cardiomyopathy in many patients, resulting in death in early adulthood. Numerous approaches are being taken to find a treatment for FRDA, including excision or correction of the repeats by genome engineering methods, gene activation with small molecules or artificial transcription factors, delivery of frataxin to affected cells by protein replacement therapy, gene therapy, or small molecules to increase frataxin protein levels, and therapies aimed at countering the cellular consequences of reduced frataxin. This review will summarize the mechanisms involved in repeat-mediated gene silencing and recent efforts aimed at development of therapeutics.

Affective disorders and endocrine disease. New insights from psychosomatic studies

This is a review of psychosomatic interactions between affective disorders (depressive and anxiety disturbances, irritable mood) and endocrine disease. Particular reference is made to stressful life events in the pathogenesis of endocrine disease, psychopathology of hormonal disturbances, and pathophysiology of hypothalamic-pituitary-adrenal axis function in depression and Cushing's disease. These psychosomatic interactions may lead to appraisal of common etiological mechanisms in endocrine and psychiatric disorders, of the value of retaining the category of organic affective syndromes in psychiatric classification, and of the need for research on quality-of-life measures in endocrine disease. The establishment of "psychoendocrine units," where both endocrinologists and psychiatrists should work, is advocated. Such psychoendocrine units may serve and benefit clinical populations who currently defy traditional medical subdivisions.

The elevation of plasma beta-endorphin levels in major depression

Day-time plasma beta-endorphin/beta-lipotrophic hormone (beta-ENDO/beta-LPH), ACTH and cortisol have been determined in 26 patients with major depression and 25 controls. beta-ENDO/beta-LPH and cortisol were significantly elevated in patients, while ACTH was not. Cortisol levels were significantly negatively correlated with age in controls as were beta-ENDO/beta-LPH and ACTH. In patients, by contrast, cortisol levels were positively, albeit not significantly, related to age. Peptide levels were not related to age in the patient group. Instead, beta-ENDO/beta-LPH was negatively correlated with clinical ratings of symptom severity in patients and positively associated with an acute psychosocial precipitant. The findings cast further light on beta-ENDO/beta-LPH as a measure of hypothalamic-pituitary over activity in depressive illness. A negative association with symptom severity suggests that beta-ENDO/beta-LPH responses are, like those of ACTH, down-regulated in the course of depressive illness.