Epiphyseal lymphoid infiltrates of the knee in adolescents.

We present three adolescents with focal lesions of the distal femur that were shown to be benign aggregates of small lymphocytes and plasma cells of unknown origin. The patients were within the age of 12 and 14 years. All lesions presented with similar MRI findings and provided the same histopathological findings in the biopsy.

Structural optimization of 2,5-thiophene amides as highly potent and selective 17β-hydroxysteroid dehydrogenase type 2 inhibitors for the treatment of osteoporosis.

Inhibition of 17β-HSD2 is an attractive mechanism for the treatment of osteoporosis. We report here the optimization of human 17β-HSD2 inhibitors in the 2,5-thiophene amide class by varying the size of the linker (n equals 0 and 2) between the amide moiety and the phenyl group. While none of the phenethylamides (n = 2) were active, most of the anilides (n = 0) turned out to moderately or strongly inhibit 17β-HSD2.

Triazole ring-opening leads to the discovery of potent nonsteroidal 17β-hydroxysteroid dehydrogenase type 2 inhibitors.

17β-Hydroxysteroid dehydrogenase type 2 (17β-HSD2) catalyzes the oxidation of the highly potent steroids: the estrogen estradiol (E2) and the androgen testosterone (T) to the less active estrone and androstenedione, respectively. Inhibition of this enzyme may help maintain the local E2 level in bone tissue when the circulating E2 level drops and is therefore a novel and promising approach for the treatment of osteoporosis. In this work, a series of new nonsteroidal and achiral 17β-HSD2 inhibitors, namely N-benzyl-diphenyl-3(or 4)-carboxamide and N-benzyl-5-phenyl-thiophene-2-carboxamide was designed and the compounds were synthesized in a two to three steps reaction.

Introduction of an electron withdrawing group on the hydroxyphenylnaphthol scaffold improves the potency of 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2) inhibitors.

Estrogen deficiency in postmenopausal women or elderly men is often associated with the skeletal disease osteoporosis. The supplementation of estradiol (E2) in osteoporotic patients is known to prevent bone fracture but cannot be administered because of adverse effect. As 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2) oxidizes E2 to its inactive form estrone (E1) and has been found in osteoblastic cells, it is an attractive target for the treatment of osteoporosis.

Discovery of a new class of bicyclic substituted hydroxyphenylmethanones as 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2) inhibitors for the treatment of osteoporosis.

E2 deficiency in elderly people has directly an effect on the skeleton and can lead to osteoporosis. As 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2) catalyses the conversion between active 17β-hydroxysteroid estradiol (E2) and testosterone (T) into their less active 17-ketosteroid and has been found in bones, 17β-HSD2 inhibitor may provide a new approach in the onset of osteoporosis. Bicyclic substituted hydroxyphenylmethanone derivatives were synthesised as steroidomimetics of the substrate E2 and were evaluated for their 17β-HSD2 inhibition and their selectivity toward 17β-HSD1, catalysing the reverse reaction the conversion of estrone (E1) into E2.

17β-HSD2 inhibitors for the treatment of osteoporosis: Identification of a promising scaffold.

17β-Hydroxysteroid dehydrogenase type 2 (17β-HSD2) catalyses the conversion of active 17β-hydroxysteroids into the less active 17-ketosteroids thereby controlling the availability of biologically active estrogens (E2) and androgens (T) in the tissues. The skeletal disease osteoporosis occurs mainly in post-menopausal women and in elderly men when the levels of estrogens and androgens, respectively, decrease. Since 17β-HSD2 is present in osteoblasts, inhibition of this enzyme may provide a new and promising approach to prevent the onset of osteoporosis, keeping a certain level in estrogens and androgens in bone cells of ageing people.

17β-Hydroxysteroid dehydrogenases (17β-HSDs) as therapeutic targets: protein structures, functions, and recent progress in inhibitor development.

17β-Hydroxysteroid dehydrogenases (17β-HSDs) are oxidoreductases, which play a key role in estrogen and androgen steroid metabolism by catalyzing final steps of the steroid biosynthesis. Up to now, 14 different subtypes have been identified in mammals, which catalyze NAD(P)H or NAD(P)(+) dependent reductions/oxidations at the 17-position of the steroid. Depending on their reductive or oxidative activities, they modulate the intracellular concentration of inactive and active steroids.

New drug-like hydroxyphenylnaphthol steroidomimetics as potent and selective 17β-hydroxysteroid dehydrogenase type 1 inhibitors for the treatment of estrogen-dependent diseases.

Inhibition of 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1) is a novel and attractive approach to reduce the local levels of the active estrogen 17β-estradiol in patients with estrogen-dependent diseases like breast cancer or endometriosis. With the aim of optimizing the biological profile of 17β-HSD1 inhibitors from the hydroxyphenylnaphthol class, structural optimizations were performed at the 1-position of the naphthalene by introduction of different heteroaromatic rings as well as substituted phenyl groups. In the latter class of compounds, which were synthesized applying Suzuki-cross coupling, the 3-methanesulfonamide 15 turned out to be a highly potent 17β-HSD1 inhibitor (IC(50) = 15 nM in a cell-free assay).