The Mitochondrial Genome And Human Mitochondrial Diseases

To date, more than 100 point mutations and several hundreds of structural rearrangements of mitochondrial DNA (mtDNA) are known too be connected with characteristic neuromuscular and other mitochondrial syndromes varying from those causing death at the neonatal stage to diseases with late ages of onset. The immediate cause of mitochondrial disorders is a defective oxidative phosphorylation. Wide phenotypic variation and the heteroplasmy phenomenon, which some authors include in mutation load, are characteristic of human mitochondrial diseases. As the numbers of cases identified and pedigrees described increase, data on the genotype-phenotype interaction and the structure and frequency of pathogenic and conditionally pathogenic mtDNA mutations in human populations are rapidly accumulated. The data on the genetics and epidemiology of mitochondrial diseases are not only important for differential diagnosis and genetic counseling. Since both neutral and mildly pathogenic mutations of mtDNA are progressively accumulated in maternal phyletic lines, molecular analysis of these mutations permits not only reconstruction of the genealogical tree of modern humans, but also estimation of the role that these mutations play in natural selection.     

Eyelid discoid lupus erythematosus and contact dermatitis: a case report

We report a patient with discoid lupus erythematosus (DLE) and associated allergic contact dermatitis (ACD) in the eyelids. In women, ACD caused by nail varnish is frequent and often seen in the eyelids. ACD caused by drugs (e.g. neomycin) is also frequent in this region. However, DLE with periorbital presentation without evidence of systemic or other cutaneous involvement is rare.     

Symposium: reproduction in baboons. The baboon oviduct: characteristics of an oestradiol-dependent oviduct-specific glycoprotein

The baboon oviductal epithelium differentiates into a tall columnarepithelium consisting of ciliated and secretory cells duringthe follicular phase of the menstrual cycle in response to risingoestradiol levels. The apical tips of these secretory cellsare filled with membrane-bound secretory granules. During theluteal phase when progesterone levels are elevated, the epitheliumregresses and deciliation occurs. Analysis of secretory proteinsobtained from explant culture media by SDS-PAGE followed byfluorography or Western Blots has revealed that the baboon oviductsynthesizes and secretes a high molecular weight glycoproteinduring the follicular phase of the cycle. Immunocytochemistrydemonstrated that the oviductal glycoprotein is localized tothe secretory granules of epithelial secretory cells, is oviductspecific, and that following secretion the oviductal glycoproteinbinds to the zona pellucida and periviteline space of ovulatedoocytes and embryos within the oviduct. Similar proteins havebeen characterized in other mammalian species. cDNA data showthat the complete coding sequence is 2228 bp for a protein of623 amino acids. A Genbank search showed that baboon oviductalglycoprotein has high homology to other oviductal glycoproteinsequences at both the nucleotide and amino acid levels. Studiesconducted to date probing the biological function of oviductalglycoprotein indicate that this protein plays a role in prefertilizationreproductive events (sperm capacitation; sperm-zona binding;zona penetration). Additional experiments are needed to reveala specific function and mechanism for this molecule.     

Effects of the calcium antagonist felodipine on renal haemodynamics, tubular sodium handling, and blood pressure in cyclosporin-treated dermatological patients

BACKGROUND: Deterioration of renal function and rise in blood pressure are clinically important side-effects of cyclosporin (CsA) treatment. Calcium antagonists may have a renoprotective effect against CsA nephrotoxicity. PURPOSE: To investigate the effect of the dihydropyridine calcium-channel blocker felodipine on renal haemodynamics, tubular sodium handling, and blood pressure in CsA- treated patients with no primary renal disease, 18 patients with various CsA-treated dermatological diseases were allocated to receive either felodipine 5 mg (extended release tablets) once daily for 4 weeks followed by placebo for 4 weeks, or vice versa, in a prospective, randomized, double-blind study. The patients were investigated before treatment and at the end of each treatment period. RESULTS: After felodipine, both glomerular filtration rate (GFR) and renal plasma flow (RPF) were significantly higher compared to placebo (89.4 +/- 17.5 (mean +/- SD) vs 79.0 +/- 15.9 ml/min and 412.0 +/- 107.6 vs 326.1 +/- 78.0 ml/min respectively, P < 0.001 for both), and filtration fraction (FF) was lower (0.22 +/- 0.03 vs 0.25 +/- 0.03, P < 0.001). Both systolic and diastolic blood pressure were lower after felodipine compared to placebo (116 +/- 11/71 +/- 7 vs 133 +/- 18/83 +/- 10 mmHg, P < 0.001 for both). Furthermore, proximal output of sodium, i.e. fractional excretion of lithium, was higher after felodipine (26.9 +/- 7.3% vs 20.4 +/- 5.5%, P < 0.001) as well as total sodium excretion (0.33 +/- 0.19 vs 0.19 +/- 0.08 mmol/min, P < 0.001). CONCLUSIONS: It is concluded, that felodipine 5 mg once daily for 4 weeks increased GFR, RPF, and sodium excretion in cyclosporin-treated dermatological patients with no primary renal disease. Furthermore, felodipine lowers blood pressure in these patients. The effects of felodipine may be due to an antagonizing effect against CsA-induced nephrotoxicity.      

Genistein aglycone improves skin repair in an incisional model of wound healing: a comparison with raloxifene and oestradiol in ovariectomized rats

Background and purpose:

Oestrogen loss at menopause is frequently related to poor wound healing. Genistein has been tested in anti-ageing cosmetic preparations with interesting results on skin health. Here, we investigated the effects of the genistein aglycones, given systemically, in an incisional model of wound healing, compared to systemic oestradiol and raloxifene.

Experimental approach:

Six months after ovariectomy (OVX), rats were randomly assigned to groups of 12 animals each and treated daily with genistein aglycone (1 and 10 mg·kg⁻¹ s.c.), raloxifene hydrochloride (0.05 and 0.5 mg·kg⁻¹ s.c.) or 17-α-ethinyl oestradiol (0.003 and 0.03 mg·kg⁻¹ s.c.) for 12 weeks. Untreated OVX and sham OVX rats were used as controls. Then, 14 or 7 days before the end of the experiment, an incisional wound healing procedure was performed and skin specimens were collected to evaluate molecular, histological and functional measurements.

Key results:

Seven and fourteen days after wounding, samples from OVX rats showed a decrease in transforming growth factor-β1, tissue transglutaminase 2 and vascular endothelial growth factor compared to samples from sham OVX rats. Oestradiol, raloxifene and genistein all significantly modified this decrease, but the lowest genistein dose exerted a greater effect than the other treatments. Moreover, the lowest dose of genistein was the most effective in improving skin healing and wound tensile strength.

Conclusions and implications:

Genistein aglycone might be an alternative therapy for the management of skin wound healing.     

Isogenic cell models of cystic fibrosis-causing variants in natively expressing pulmonary epithelial cells

BackgroundAssessment of approved drugs and developmental drug candidates for rare cystic fibrosis (CF)-causing variants of the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) requires abundant material from relevant models.MethodsIsogenic cell lines harboring CFTR variants in the native genomic context were created through the development and utilization of a footprint-less, CRISPR/Cas9 gene editing pipeline in 16HBE14o- immortalized bronchial epithelial cells.ResultsIsogenic, homozygous cell lines for three CFTR variants (F508del and the two most common CF-causing nonsense variants, G542X and W1282X) were established and characterized. The F508del model recapitulates the known molecular pathology and pharmacology. The two models of nonsense variants (G542X and W1282X) are sensitive to Nonsense Mediated mRNA Decay (NMD) and responsive to reference compounds that inhibit NMD and promote ribosomal readthrough.ConclusionsWe present a versatile, efficient gene editing pipeline that can be used to create CFTR variants in the native genomic context and the utilization of this pipeline to create homozygous cell models for the CF-causing variants F508del, G542X, and W1282X. The resulting cell lines provide a virtually unlimited source of material with specific pathogenic mutations that can be used in a variety of assays, including functional assays.