The Ca(2+)- and calmodulin-dependent protein phosphatase calcineurin is inhibited by the immunosuppressant drug cyclosporin A in the presence of cyclophilin A or B. Of the two isoforms, cyclophilin B is more potent by a factor of 2-5 when either the phosphoprotein [32P]casein or the [32P]phosphoserine [Ser(32P)] form of the 19-residue bovine cardiac cAMP-dependent protein kinase regulatory subu...

Candida lusitaniae is an emerging fungal pathogen that infects immunocompromised patients including HIV/AIDS, cancer, and neonatal pediatric patients. Though less prevalent than other Candida species, C. lusitaniae is unique in its ability to develop resistance to amphotericin B. We investigated the role of the calcium-activated protein phosphatase calcineurin in several virulence attributes of...

Memory extinction refers to a gradual decrease of the previously acquired response when exposed to conditional stimulus without pairing with unconditional stimulus. Here we show for the first time that fear training-induced phosphorylation of specific substrates in the rat amygdala is reduced after extinction trials and is accompanied by an increase in the protein level and enzymatic activity o...

Here, we demonstrate that the Ca(2+)/calmodulin-sensitive phosphatase calcineurin is a necessary downstream mediator for osteoclast differentiation. Using quantitative PCR, we detected the calcineurin isoforms Aalpha, Abeta, Agamma (catalytic), and B1 (regulatory) in osteoclast precursor RAW-C3 cells. We found that, although the expression of these isoforms remained relatively unchanged during ...

The calcineurin inhibitors, tacrolimus and cyclosporine, are commonly used immunosuppressants, and transplant patients on these medications often develop gastrointestinal symptoms. This in vitro study investigated their effects on intestinal cellular respiration (the process of delivering nutrients and O2 to the mitochondria, oxidation of reduced metabolic fuels, passage of electrons to O2, and...

Azoles target the ergosterol biosynthetic enzyme lanosterol 14alpha-demethylase and are a widely applied class of antifungal agents because of their broad therapeutic window, wide spectrum of activity, and low toxicity. Unfortunately, azoles are generally fungistatic and resistance to fluconazole is emerging in several fungal pathogens. We recently established that the protein phosphatase calci...

In vitro studies have demonstrated that cyclosporine A (CsA) acts by inhibiting the phosphatase activity of calcineurin, an important mediator of T-cell activation. The relationship of CsA administration in vivo, calcineurin activity, and graft-versus-host disease (GVHD) has yet to be studied. The calcineurin activities of mononuclear cells isolated from 62 bone marrow transplant recipients and...

The immunosuppressive calcineurin inhibitors cyclosporine A and tacrolimus alter T-cell subsets and can cause hypertension, vascular dysfunction, and renal toxicity. We and others have reported that cyclosporine A and tacrolimus decrease anti-inflammatory regulatory T cells and increase proinflammatory interleukin-17-producing T cells; therefore, we hypothesized that inhibition of these effects...

Cutaneous lupus erythematosus (CLE) encompasses a variety of lesions that may be refractory to systemic or topical agents. Discoid lupus erythematosus (DLE) and subacute cutaneous lupus erythematosus (SCLE) are the most common lesions in clinical practice. The topical calcineurin inhibitors, tacrolimus and pimecrolimus, have been used to treat resistant cutaneous lupus since 2002 and inhibit th...

      Schimke immune-osseous dysplasia (SIOD) is a rare autosomal recessive disorder presented with specific facial features, skeletal dysplasia, steroid resistance nephrotic syndrome (SRNS) and cellular immune insufficiency. This is a SIOD case reported from Iran. He was 5 years old boy when evaluated for proteinuria and short stature. In appearance, we detected hyperpigmented macules, kyphosc...