c-myb Proto-Oncogene Is Expressed by Quiescent Scleroderma Fibroblasts and, Unlike B-myb Gene, Does Not Correlate With Proliferation

Systemic sclerosis (scleroderma) is characterized by excessive deposition of extracellular matrix constituents. Although it has been proposed that tissue fibrosis is due to increased fibroblast synthesis of various collagen polypeptides, there is some experimental evidence that patients with systemic sclerosis have a defect in the control of fibroblast growth. The myb family of genes includes, among others, the c-myb proto-oncogene and the structurally related gene, B-myb, which are both implicated in the regulation of differentiation and/or proliferation of hematopoietic and nonhematopoietic cells. To elucidate the molecular basis responsible for scleroderma fibroblast proliferation, we therefore elected to investigate the expression of c-myb and B-myb genes in scleroderma and control cells. Using the reverse transcriptase polymerase chain reaction technique, we detected c-myb transcripts in scleroderma skin fibroblasts rendered quiescent by serum deprivation. Under the game experimental conditions, c-myb message was not found in normal skin fibroblasts, but, after serum stimulation, c-myb RNA was clearly evident from 3 to 72h in both normal and pathologic cells. Treatment of these cells with c-myb antisense oligonucleotides caused downregulation of c-myb expression, and the inhibition of scleroderma fibroblast proliferation was 42%, whereas in normal fibroblasts the inhibition was weaker (22%). In contrast to c-myb, in normal and scleroderma fibroblasts the level of expression of B-myb correlated with cell proliferation assessed by cell count, and densitometric analysis showed that B-myb message was 1.5–5 times higher in most of pathologic cells studied. The antisense B-myb oligonucleotides had a weaker antiproliferative effect compared with antisense c-myb, inhibiting scleroderma and normal fibroblasts by 23% and 13%, respectively. These data suggest that the B-myb and c-myb genes may play a role in scleroderma fibroblast proliferation and function

Therapeutic Effects of the Superoxide Dismutase Mimetic Compound Mn(II)Me2DO2A on Experimental Articular Pain in Rats.

Superoxide anion () is overproduced in joint inflammation, rheumatoid arthritis, and osteoarthritis. Increased production leads to tissue damage, articular degeneration, and pain. In these conditions, the physiological defense against , superoxide dismutases (SOD) are decreased. The complex MnL4 is a potent SOD mimetic, and in this study it was tested in inflammatory and osteoarticular rat pain models. In vivo protocols were approved by the animal Ethical Committee of the University of Florence. Pain was measured by paw pressure and hind limb weight bearing alterations tests. MnL4 (15 mg kg−1) acutely administered, significantly reduced pain induced by carrageenan, complete Freund’s adjuvant (CFA), and sodium monoiodoacetate (MIA). In CFA and MIA protocols, it ameliorated the alteration of postural equilibrium. When administered by osmotic pump in the MIA osteoarthritis, MnL4 reduced pain, articular derangement, plasma TNF alpha levels, and protein carbonylation. The scaffold ring was ineffective. MnL4 (10−7 M) prevented the lipid peroxidation of isolated human chondrocytes when was produced by RAW 264.7. MnL4 behaves as a potent pain reliever in acute inflammatory and chronic articular pain, being its efficacy related to antioxidant property. Therefore MnL4 appears as a novel protective compound potentially suitable for the treatment of joint diseases

Phytoestrogens: food or drug?

Within the past several years, the relation between diet and health has been accepted by the mainstream nutrition community and in this connection interest in the physiological role of bioactive compounds present in plants has dramatically increased over the last decade

Cystic bone angiomatosis: A case report treated with aminobisphosphonates and review of the literature

Cystic angiomatosis (CA) is a rare disease characterized by multifocal hemangiomatous and/or lymphangiomatous lesions of the skeleton with possible visceral organ involvement. The exact pathogenetic mechanism of the disease is still unknown. We describe a patient affected by CA of bone treated with surgical procedures and subsequently with intravenous aminobisphosphonates for 7 years. During the follow-up progression of lesions, the painful symptoms, markers of bone turnover, computed tomographic examination, and bone mineral density were evaluated. Aminobisphosphonate therapy showed an immediate effectiveness in reducing bone pain, with a significant decrease in circulating bone alkaline phosphatase and stable radiological findings during clinical follow-up. In addition, at baseline, high levels of bone biomarkers and cytokines (osteoprotegerin, osteopontin, and interleukin-6) capable of controlling bone metabolism and angiomatosis were identified. Aminobisphosphonate treatment produced a decrease of all these increased markers. Local cell therapy with bone marrow osteoblast precursors did not produce any measurable clinical improvement. Aminobisphosphonate therapy represents an elective treatment for bone angiomatosis syndromes, but further studies are necessary to understand the molecular basis of these disorders and of their pharmacological treatment. © 2013 Springer Science+Business Media New York

Methodological models for in vitro amplification and maintenance of human articular chondrocytes from elderly patients

Articular cartilage defects, an exceedingly common problem closely correlated with advancing age, is characterized by lack of spontaneous resolution because of the limited regenerative capacity of adult articular chondrocytes. Medical and surgical therapies yield unsatisfactory short-lasting results. Recently, cultured autologous chondrocytes have been proposed as a source to promote repair of deep cartilage defects. Despite encouraging preliminary results, this approach is not yet routinely applicable in clinical practice, but for young patients. One critical points is the isolation and ex vivo expansion of large enough number of differentiated articular chondrocytes. In general, human articular chondrocytes grown in monolayer cultures tend to undergo dedifferentiation. This reversible process produces morphological changes by which cells acquire fibroblast-like features, loosing typical functional characteristics, such as the ability to synthesize type II collagen. The aim of this study was to isolate human articular chondrocytes from elderly patients and to carefully characterize their morphological, proliferative, and differentiative features. Cells were morphologically analyzed by optic and transmission electron microscopy (TEM). Production of periodic acid-schiff (PAS)-positive cellular products and of type II collagen mRNA was monitored at different cellular passages. Typical chondrocytic characteristics were also studied in a suspension culture system with cells encapsulated in alginate-polylysine-alginate (APA) membranes. Results showed that human articular chondrocytes can be expanded in monolayers for several passages, and then microencapsulated, retaining their morphological and functional characteristics. The results obtained could contribute to optimize expansion and redifferentiation sequences for applying cartilage tissue engineering in the elderly patients

Clodronate acts on human osteoclastic cell proliferation, differentiation and function in a bioreversible manner

Background. Clodronate is used in high bone resorption diseases. Its action was defined as “cytotoxic” based on the induced cellular ATP loss, without any experimental verification of reversibility. In the present report the reversibility of clodronate action was tested on cultured human osteoclastic cell cultures. As “in vitro” bioeffects of clodronate are reversible, this compound should not be defined as “cytotoxic”

Fatal Neurodissemination and SARS-CoV-2 Tropism in K18-hACE2 Mice Is Only Partially Dependent on hACE2 Expression

Animal models recapitulating COVID-19 are critical to enhance our understanding of SARS-CoV-2 pathogenesis. Intranasally inoculated transgenic mice expressing human angiotensin-converting enzyme 2 under the cytokeratin 18 promoter (K18-hACE2) represent a lethal model of SARS-CoV-2 infection. We evaluated the clinical and virological dynamics of SARS-CoV-2 using two intranasal doses (10(4) and 10(6) PFUs), with a detailed spatiotemporal pathologic analysis of the 10(6) dose cohort. Despite generally mild-to-moderate pneumonia, clinical decline resulting in euthanasia or death was commonly associated with hypothermia and viral neurodissemination independent of inoculation dose. Neuroinvasion was first observed at 4 days post-infection, initially restricted to the olfactory bulb suggesting axonal transport via the olfactory neuroepithelium as the earliest portal of entry. Absence of viremia suggests neuroinvasion occurs independently of transport across the blood-brain barrier. SARS-CoV-2 tropism was neither restricted to ACE2-expressing cells (e.g., AT1 pneumocytes), nor inclusive of some ACE2-positive cell lineages (e.g., bronchiolar epithelium and brain vasculature). Absence of detectable ACE2 protein expression in neurons but overexpression in neuroepithelium suggest this as the most likely portal of neuroinvasion, with subsequent ACE2 independent lethal neurodissemination. A paucity of epidemiological data and contradicting evidence for neuroinvasion and neurodissemination in humans call into question the translational relevance of this model