OSTEOGROW – novi lijek za koštanu regeneraciju

Molecular processes required for bone repair are a prerequisite for the development of new biological procedures for stimulation of bone healing. Currently, there is no adequate therapy available that can accelerate long bone fractures healing. Specifically there is a need for the development of a new osteogenic device that will offer safe healing in particular of the trabecular bone. The Osteogrow project has developed a new therapy that promises to be safe and cost-effective and might decrease the need for secondary interventions. The Osteogrow device contains an autologous blood coagulum (ABC) made from the peripheral blood and recombinant bone morphogenetic protein 6 (BMP6). BMP6 has been selected as compared to BMP2 or BMP7/OP1 as it does not bind avidly to the BMP antagonist Noggin. ABC was chosen as a substrate for the delivery since BMP6 binds tightly to the number of plasma proteins resulting in the sustained and linear release over seven to ten days without provoking inflammation and immune responses. With support of the EU FP7 grant we have completed the preclinical development of Osteogrow and started Osteogrow first in humans (FIH) clinical studies. Osteogrow is tested clinically in two indications: the distal radial fracture and high tibial osteotomy to establish the safety and potential efficacy for Osteogrow for regeneration of the metaphyseal bone. Beyond currently tested clinical indications, this therapy would also be employed for posterolateral spinal fusion to treat degenerative spine disorders.Molekularni procesi potrebni za regeneraciju kosti su preduvjet za razvoj novih bioloških postupaka neophodnih za stimulaciju koštanog cijeljenja. U ovome trenutku na tržištu ne postoji adekvatna terapija koja može ubrzati cijeljenje prijeloma dugih kostiju. Postoji potreba za razvojem nove koštane naprave koji će ponuditi sigurno i ekonomično liječenje. Projekt Osteogrow razvio je potpuno novu terapiju koja obećava da će biti sigurna i isplativa te će smanjiti potrebu za sekundarnim intervencijama. Osteogrow sadrži autologni krvni ugrušak (ABC) kao nosač koji se sastoji od periferne krvi u koji se dodaje rekombinantni protein BMP6 (engl. Bone Morphogenetic Protein). BMP6 je odabran kao poželjni koštani morfogentski protein u usporedbi s BMP2 ili BMP7 / OP1 jer se ne veže na BMP antagonist, Noggin. Autologni krvni ugrušak odabran je kao nosač BMP6 molekule, jer se veliki broj proteina plazme čvrsto veže na BMP6. Uz potporu EU FP7 programa završena su pretklinička testiranja Osteogrow-a i započela je prva primjena Osteogrow lijeka u ljudi (FIH) unutar odobrene kliničke studije. Osteogrow se testira unutar dvije indikacije: distalna radijalna fraktura i visoka osteotomija goljenične kosti koje su odabrane kako bi se utvrdila sigurnost i potencijalna učinkovitost Osteogrow lijeka u regeneraciji metafizalne kosti. Osim trenutno testiranih kliničkih indikacija, ova terapija će se koristiti za liječenje degenerativnih bolesti kralježnice

Analiza ekspresije gena u koštanom tkivu osteoporotičnih miševa

Ovaricetomized (OVX) animals represent an optimal model to investigate bone loss in osteoporosis. To further elucidate the underlying mechanisms of decreased bone formation and increased bone resorption following OVX, we conducted gene expression profiling experiments using bone samples of ovariectomized C57BL/6J mice. Following OVX, genes involved in immune response, cell cycle regulation, growth, apoptosis and bone resorption were upregulated, while genes that are important for regular cell processes, mitosis, metabolism of carbohydrates, extracellular matrix structure, angiogenesis, skeletal development and morphogenesis were downregulated. Among bone specific genes we observed upregulation of interleukin 7 (IL-7), IL-7 receptor and matrix metallopeptidase 8, while genes such as transforming growth factor-beta 3, procollagen type I and procollagen type VI exhibited marked decrease in expression. We also observed downregulation of two genes, parathyroid hormone receptor 1 and WD repeat domain 5, that are involved in skeletal development but were not previously reported to be altered in osteoporosis. We further performed gene set enrichment analysis (GSEA) in order to calculate enrichment of pathways specifically altered in murine bones following ovariectomy. In conclusion, OVX greatly influences expression of various genes involved in diverse biological processes confirming the notion that numerous pathways play an important role in pathophysiology of osteoporosis.Osteoporoza je najčešća metabolička bolest kostiju, obilježena smanjenom koštanom masom i poremećenom koštanom mikroarhitekturom. Prikladan životinjski model za istraživanje osteoporoze su ovarijektomirani miševi. Kako bismo pobliže istražili mehanizme smanjene koštane formacije i pojačane koštane razgradnje nakon ovarijektomije, proveli smo pokuse ekspresijskog profiliranja koristeći se uzorcima kostiju ovarijektomiranih miševa soja C57BL/6J. Nakon ovarijektomije pojačava se izražaj gena uključenih u imunološki odgovor, regulaciju staničnog ciklusa, apoptozu i koštanu razgradnju, dok se ekspresija gena bitnih za mitozu, metabolizam ugljikohidrata, razvoj kosti, strukturu izvanstaničnog matriksa i angiogenezu smanjuje. Od koštano specifičnih gena, interleukin 7 (IL-7), receptor za IL-7 i matriks metalopeptidazu 8 imali su pojačan izražaj, dok je za transformirajući čimbenik rasta -beta 3, prokolagen tipa I i tipa VI uočen smanjen genski izražaj. Također smo otkrili smanjen izražaj dvaju gena, i to receptora 1 za paratireoidni hormon i WD ponavljajuću domenu 5, koji su bitni za koštani razvoj, a promjena njihove regulacije nije do sada primijećena u osteoporozi. Kako bismo dodatno istražili obogaćenost pojedinih funkcionalnih skupina gena u kostima ovarijetkomiranih životinja, podatke smo analizirali s pomoću algoritma gene set enrichment analysis (GSEA). Zaključno, ovarijektomija značajno utječe na izražaj brojnih gena uključenih u različite biološke procese, što potvrđuje pretpostavku da mnogi molekularni putovi imaju važnu ulogu u patofiziologiji osteoporoze

VE-cadherin facilitates BMP-induced endothelial cell permeability and signaling

Several vascular disorders, such as aberrant angiogenesis, atherosclerosis and pulmonary hypertension, have been linked to dysfunctional BMP signaling. Vascular hyperpermeability via distortion of endothelial cell adherens junctions is a common feature of these diseases, but the role of BMPs in this process has not been investigated. BMP signaling is initiated by binding of ligand to, and activation of, BMP type I (BMPRI) and type II (BMPRII) receptors. Internalization of VE-cadherin as well as c-Src kinase-dependent phosphorylation have been implicated in the loosening of cell-cell contacts, thereby modulating vascular permeability. Here we demonstrate that BMP6 induces hyperpermeabilization of human endothelial cells by inducing internalization and c-Src-dependent phosphorylation of VE-cadherin. Furthermore, we show BMP-dependent physical interaction of VE-cadherin with the BMP receptor ALK2 (BMPRI) and BMPRII, resulting in stabilization of the BMP receptor complex and, thereby, the support of BMP6-Smad signaling. Our results provide first insights into the molecular mechanism of BMP-induced vascular permeability, a hallmark of various vascular diseases, and provide the basis for further investigations of BMPs as regulators of vascular integrity, both under physiological and pathophysiological conditions

A simple rodent subcutaneous assay for identification of new osteoinductive molecules: The key method for screening of novel bone regeneration implants

Treatment of large bone defects and degenerative diseases of the spine is among the most challeng- ing and still unresolved issues in clinical medicine. Therefore, substantial effort has been devoted to the development of novel bone regenerative therapies. Due to their potent osteoinductive properties, Bone Morphogenetic Proteins (BMPs) have been the basis for the development of novel strategies for bone regeneration. The use of animal models is an indispensable part of the preclinical testing of novel therapeutic solutions. The rat subcutaneous assay became the initial screening procedure for the evalu- ation of promising BMP-based osteoinductive devices for bone regeneration because only osteogenic BMPs can induce new bone at any ectopic rodent site. Moreover, this model is used for research on the mechanisms of ectopic bone formation as well as for the evaluation of the inflammatory response to different materials. In this review, we provided an overview of the assay development and previously conducted studies with different methods (flow cytometry, histological and microCT analyses) for the study outcome evaluation. Moreover, we addressed essential issues in the experimental design such as the follow-up period and the sample size. The rat subcutaneous bone induction assay layed the founda- tion for isolation and identification of BMPs followed by testing of new osteogenic devices in higher animal species and humans

OSTEOGROW – nova terapija za koštanu regeneraciju

Cilj ovog istraživanja je procijeniti djelotvornost rhBMP6 (Genera istraživanja) u cijeljenju kritičnog defekta lakatne kosti kod kunića u usporedbi s komercijalno dostupnim nosačem. Model je prethodno opisan u nekoliko objavljenih studija i odobren od strane etičkog povjerenstva Medicinskog fakulteta Sveučilišta u Zagrebu u cilju testiranja sigurnosti i učinkovitosti nove naprave. U navedenom pokusu korišteni su odrasli mužjaci novozelandskih bijelih kunića. Koštani defekti ispunjeni su autolognim krvnim ugruškom sa ili bez dodatka rhBMP6 te rhBMP7 na kolagenoj spužvici kao nosaču. Životinje su praćene u periodu od 8 tjedana. Stvaranje novog koštanog tkiva praćeno je radiografski svaka dva tjedna nakon implantacije. Rezultati pokazuju da su implantati koji su se sastojali od autolognog ugruška i rhBMP6 rezultirali potpunim premoštenjem koštanog defekta ulne. Niti jedna od kontrolnih životinja koje su tretirane samo autolognim ugruškom kao nosačem (bez BMP6) nije postigla premoštenje koštanog defekta. Cijeljenje koštanog defekta korištenjem autolognog ugruška s rhBMP6 u usporedbi s kolagenom spužvicom natopljenom rhBMP7 bilo je puno brže i učinkovitije, bez znakova lokalne upale i edema. Novi autologni nosač s rhBMP6 na novi i učinkovit način rješava problem poticanja i stvaranja novog koštanog tkiva te premoštenje koštanog defekta i tako predstavlja novo moguće rješenje za sve nedostatke koji su proizašli korištenjem postojećih komercijalno dostupnih nosača

Osteogenic Protein-1 Is Produced by Human Fetal Trophoblasts In Vivo and Regulates the Synthesis of Chorionic Gonadotropin and Progesterone by Trophoblasts In Vitro

Peer Reviewe

Treatment of Osteoporosis

Osteoporoza je jedna od najčešćih metaboličkih bolesti i zahvaća 8 % do 10 % stanovništva. Budući da je prijelom najteža posljedica osteoporoze, vrlo je važno otkriti bolesnike koji imaju rizik nastanka prijeloma, dati im farmakološku terapiju i savjetovati im promjenu načina života. Nekoliko je lijekova pokazalo sposobnost smanjenja broja prijeloma kralježnice i/ili perifernog skeleta u bolesnika s osteoporozom. Antiresorptivni su lijekovi temelj terapije, ali su i anabolički lijekovi odnedavno proširili mogućnosti liječenja. Antiresorptivni lijekovi, estrogeni, selektivni modulatori estrogenskih receptora, bisfosfonati i kalcitonin, djeluju tako da smanjuju koštanu pregradnju. Paratireoidni hormon potiče novo stvaranje kosti popravljajući arhitekturu i gustoću kosti. Stroncijev ranelat smanjuje rizik osteoporotičnih prijeloma djelujući na oboje - smanjenje razgradnje i povećanje izgradnje kosti. Druga potencijalna liječenja osteoporoze također su opisana u ovome članku.Osteoporosis is among the most frequent metabolic diseases affecting 8 % to 10 % of the population. Since the most disturbing outcome of osteoporosis is a fracture, it is important to identify patients at risk and intervene with pharmacologic therapies and lifestyle changes. Several drugs have shown their ability to reduce vertebral and/or peripheral fractures in patients with osteoporosis. Antiresorptive agents are a basis of therapy, but anabolic drugs have recently widened therapeutic options. Antiresorptive medications, estrogens, selective estrogen receptor modulators, bisphosphonates and calcitonins, work by reducing the rates of bone remodeling. Parathyroid hormone stimulates new bone formation, repairing architectural defects and improving bone density. Strontium ranelate reduces the risk for osteoporotic fractures by both inhibiting bone resorption and increasing bone formation. Other potential therapies for osteoporosis are also reviewed in this article