Calcitriol exerts anti-inflammatory effects in keratinocytes treated with autoantibodies from a patient with bullous pemphigoid.

BACKGROUND: The hormonally active vitamin D metabolite calcitriol and its analogues exert potent effects on cellular differentiation and regulation of immune responses. Although topical vitamin D analogues are widely used for treatment of psoriasis and vitamin D has been increasingly implicated in prevention and protection from several autoimmune diseases, experimental and clinical data in autoimmune bullous diseases are generally lacking. OBJECTIVE: Here, we investigated the effects of calcitriol on keratinocytes treated by bullous pemphigoid (BP) autoantibodies. METHODS: Human keratinocyte (HaCaT) cells were treated with purified human BP or normal IgG from one BP patient and healthy subject, respectively, in the absence or presence of calcitriol and effects on (i) cell viability, (ii) IL-6 and IL-8 secretion, (iii) STAT3 and NFκB activation, (iv) heat shock protein 70 (Hsp70) level, and (v) vitamin D receptor (VDR) expression were studied. RESULTS: We found that BP IgG-induced IL-6 and IL-8 release from HaCaT cells was reduced in the presence of non-toxic doses of calcitriol. Additionally, calcitriol blunted BP IgG-mediated STAT3 phosphorylation and NFκB activity, whereas Hsp70 and VDR expression were not affected. CONCLUSION: Although the results of this study are based on autoantibodies prepared from a single patient, they show that calcitriol protects from BP IgG-induced inflammatory processes in vitro, thus favouring its potential inclusion into the therapeutic repertoire of BP.

The significance of macroautophagy in health and disease.

During the past decade there has been a substantial increase in macroautophagy (herein simply referred to as autophagy) research due to a growing understanding of this process, coupled with improved new techniques for its detection. Autophagy (auto - self, phagy - eating) is defined as a fundamental lysosomal catabolic pathway responsible for degrading long-lived proteins, protein aggregates, oxidised lipids, damaged organelles, and even microbial invaders. Although autophagy occurs at basal levels in normal conditions, many different forms of metabolic stress, including starvation, hypoxia, high temperature, high culture density, hormones, and growth factor deprivation can dramatically stimulate an autophagic response. Autophagy plays a critical role in maintaining cellular homeostasis and genomic integrity and therefore has been implicated in many physiological activities such development, differentiation, and tissue remodelling.Consequently, defects in autophagy have been linked to various human diseases such as neurodegenerative and muscle disorders, cancers, cardiac failure, and inflammatory disorders. This mini-review summarises current knowledge in a field of mammalian autophagy and considers the significance of autophagy in human physiology and pathology.

Ultrastructural aspects of acute pancreatitis induced by 2, 2'-azobis (2-amidinopropane) dihydrochloride (AAPH) in rats.

Pathophysiology of acute pancreatitis (AP) has not been clearly established; nevertheless, accumulating evidence implicates highly reactive oxygen species (ROS) as important mediators of exocrine tissue damage. In this study, we used a water-soluble radical initiator, 2,2 -azobis-(2-amidinopropane) dihydrochloride (AAPH), to investigate the consequences of oxidative stress insult to the rat pancreas. The detailed characterisation of acini ultrastructural changes in the early course (3, 6, 12, 24 h) of AAPH-induced pancreatitis (40 mg/1 kg body weight) was performed. Considerable damage to the mitochondria in acinar cells manifested by increased translucence of the matrix, partial destruction of cristae, and formation of myelin figures were noted. At the same time, focal dilation, degranulation of rough endoplasmic reticulum, and reduced number of zymogen granules was observed. The most prominent ultrastructural feature was accumulation of highly polymorphic cytoplasmic vacuoles in acinar cells. Double membrane-bound autophagosomes, different in size and shape, with sequestered organelles, autophagolysosomes, and large, empty, single-membrane-bound vacuoles were observed within the cytoplasm. The results indicate that intensive and impaired autophagy mediates pathological accumulation of vacuoles in acinar cells. The rat model of acute pancreatitis induced by AAPH is useful to investigate the early events of oxidative stress insult to the pancreas.

Controlled cholesterol efflux from the aortic smooth muscle cells triggers microheterogeneity of plasma membrane lipids and induces modification of the mitochondrial topology.

It is generally accepted that phospholipids of plasma membrane display lateral segregation into small microdomains commonly known as lipid rafts. Such lateral lipid organization is under the control of cholesterol. Cholesterol depletion evolved by methyl-beta-cyclodextrin (MCD) has been found to induce further marked perturbation in lateral lipid organization, evidenced in the high field part of electron paramagnetic resonance spectra of plasma membranes labelled with a spectroscopic probe, namely 5-doxyl-stearic acid (5DOXS). Such perturbation of surface lipid topo-logy has been found to induce distinct changes in the mitochondrial morpho-logy, i.e. switch from filamentous form into small granular form.

Hippocampal capillaries in different age groups of chronically ethanol-intoxicated rats. Morphometrical studies.

The influence of chronic ethanol intoxication on the terminal vascularization of particular hippocampal fields and layers was investigated in different age groups of rats. Thirty-six male Wistar rats aged 6 weeks were used in the study. For twelve months 24 of them drank only 25% ethanol--12 starting at 6-week-age and 12 at 3-month-age. The control group of 12 rats drank only water. As an effect of long-term ethanol exposure on hippocampal capillaries we observed the increase in the terminal vessel diameter and the decrease in microvascular length, surface, and volume densities. These changes varied between different age groups and between particular hippocampal regions. The observed age and regional differentiation of ethanol-related microvascular changes did not correlate well with the damaging effects of alcohol on corresponding neuronal elements, which emphasizes the very complicated pathogenesis of ethanol-induced injuries.

Morphological changes of aortal smooth muscle cells exposed to calcitriol in culture.

INTRODUCTION: A number of observations suggest that vitamin D plays an important role in maintaining normal cardiovascular function, through its receptors in cardiac muscle or in aortal smooth muscle cells (SMCs). The purpose of this study was to determine the effect of vitamin D active metabolite--calcitriol [1,25(OH)2D3] on aortal SMCs. MATERIAL AND METHODS: The cells were isolated from the aortal media of newborn rats by enzymatic digestion and maintained for 6 weeks in primary culture. 1.2 microM of calcitriol was added to the medium every second day. RESULTS: Light microscopic investigations revealed that the control SMCs formed multilayer with characteristic 'hills and valleys'. Uniform cellular growth patterns were observed after calcitriol treatment. Ultrastructural studies indicated more rapid modulation of SMCs from the 'contractile' to the 'synthetic' phenotype following calcitriol treatment. Elastic fibers were more abundant in treated than in control cultures. The scanning electron microscope showed an increase of regular microvilli on the surface of SMCs. Morphometrical analysis of nuclei demonstrated phenotypic heterogeneity in populations of aortal SMCs. These results suggest that 1) calcitriol can induce changes in the phenotype and in the growth pattern of aortal SMCs, which may be associated with the onset or progression of the atherosclerosis process, 2) the basis of phenotypic changes is related to the stimulation of proliferative activity in these cells.

Kaposi's sarcoma following long-term immunosuppressive therapy: clinical, histologic, and ultrastructural study.

Multifocal Kaposi's sarcoma in a patient with chronic myeloid leukemia treated with busulfan, a cytostatic and suppressive drug, is reviewed. After five years of treatment, during which temporary remissions occurred, the patient experienced a relapse of leukemia and a considerable immune deficiency. This was expressed by a decrease in the ratio of CD4/CD8 lymphocytes in the peripheral blood. The relation of Kaposi's sarcoma with leukemia, as well as with the state of immunity in this case, does not evoke any doubts. Verification of oncologic treatment brought about a remission of leukemia, an improvement in the patient's immune state, as well as an inhibition of new foci of the Kaposi's sarcoma in the skin in the course of a few months of follow-up evaluation.

Interstitial tissue fraction. The prognostic marker in membranoproliferative glomerulonephritis in children.

OBJECTIVE: To explain the differences in the clinical course of membranoproliferative glomerulonephritis (MPGN) in children and to find some prognostic markers at the disease onset that correlate with the disease outcome. STUDY DESIGN: We reviewed clinical histories and laboratory findings, reexamined kidney biopsies performed at the disease onset and evaluated volume relations between kidney components in children with the diagnosis of MPGN. RESULTS: Children were divided into three groups based on their final clinical status: I. children without features of active nephropathy, II. children with persistent nephropathy, and III. children who died of kidney disease and those who had chronic renal insufficiency. Reevaluation of kidney biopsies led to a change in the histopathologic diagnosis in several cases in all three groups. Morphometric analysis showed increasing interstitial tissue volume from group I through group III in MPGN and other forms of glomerulonephritis diagnosed after reevaluation. All the morphologic, clinical and laboratory features estimated by means of multivariate analysis of variance showed statistically significant individual characteristics of each group defined by clinical outcome. CONCLUSION: Increased interstitial tissue volume in the kidney biopsy at the disease onset is a negative prognostic factor in MPGN.

Effects of vitamin D on aortic smooth muscle cells in culture.

Earlier investigations on vitamin-induced experimental atherosclerosis in rats suggested that smooth muscle cells (SMCs) play a pivotal role in development of these vascular abnormalities. This study demonstrates the effects of vitamin D (ergocalciferol) on SMCs of rat aorta in tissue culture. SMCs were obtained from aortas of newborn rats by enzymatic digestion and maintained for 6 wk in primary culture with vitamin D (1.2 nm) in the culture medium. The effects of vitamin D on SMCs, as compared with control SMCs cultures, were evaluated by light and electron microscopy. Growth of SMCs was characterized by cell counting, measurement of DNA and protein content, and by analysis of the nucleolar organizing regions. Vitamin D had no effect on proliferation of SMCs but stimulated synthesis and intercellular deposition of elastic fibres and had a stabilizing effect on the musculo-elastic multilayer formed by the cultured cells. In addition, it prevented degeneration of SMCs, with long-term preservation of the typical phenotype in primary culture.

[Complete heart block treated with electrotherapy in a 30-year-old pregnant women with Kearns-Sayre syndrome]. / Blok calkowity serca wymagajacy elektroterapii u 30-letniej ciezarnej z zespolem Kearns-Sayre.

Kearns-Sayre syndrome (KSS) is a form of mitochondrial myopathy in which specific clinical features, namely progressive external ophthalmoplegia, pigmentary retinal degeneration and onset before age 20 occur. It can also be associated with cardiac conduction defects, neurological and variety of endocrine and metabolic disorders. Recognition of mtDNA deletion as the genetic basis of KSS has confirmed the validity of clinical criteria. The purpose of the report is to describe a 30-year-old woman presenting typical clinical features of KSS. On muscle biopsy ragged red fibres and mitochondrial abnormalities on electron microscopy were seen. In spite of menstrual disturbances she became pregnant and delivered health child. In 30 week of pregnancy the VVI pacemaker was implanted because of syncope most probably related to paroxysmal complete heart block.

Comparative morphometric analysis of terminal vascularization of hippocampal CA1 and CA3 sectors in Mongolian gerbils.

Comparative morphometric analysis of terminal vascularization (vessels with a diameter lower than 12.5 microns) in the ischemia-sensitive sector CA1 and the ischemia-resistant sector CA3 of Ammon's horn in Mongolian gerbils was performed. Basing on numerous computer-counted parameters characterizing the terminal vascular network in both hippocampal sectors and its relationship to the surrounding tissue, it was shown that a number of capillary vessels, their average diameter, and exchange and flow surfaces were to a statistically significant degree lower in the pyramidal layer of the CA1 sector as compared with those in CA3 sector. The number of pyramidal neurons in the pyramidal layer, counted per surface unit was in sector CA1 higher than in sector CA3. The obtained data indicate clearly an angioarchitectonically dependent lower microvascular capacity of sector CA1. However, these differences do not indicate per se a leading role of the vascular factor in the pathomechanism of selective vulnerability to ischemia. They may be a factor facilitating neuronal damage evoked by the excitotoxic action of glutamate, observed in CA1 sector as a result of forebrain ischemia.