Scaffolds for bone tissue regeneration

Introduction. There are many types of scaffolds prepared in order to regenerate bone tissue defects [2]. In performed research were tested matrices of natural origin. Materials and methods. Collagen sponges were obtained from collagen extracted from the bovine Achilles tendon [3], which were cross-linked with 25% Glutaraldehyde (GA) vapors, and with 25 mM Riboflavin solution under the action of UV-A rays during one hour. Rabbit femoral and iliac wing bones were demineralized in 0.6 M HCl solution. Bone cells (BC) and mesenchymal stem cells (MSC) were isolated from rabbit [4, 5], to perform the MTT assay and to evalulate cellular adhesion on scaffolds with DAPI. The ultrastructure of the scaffolds was analyzed by scanning electron microscopy (SEM). Results. The MTT assay on BC and MSC showed a high cellular activity. Also, seeded cells had a good adhesion and proliferation on the prepared scaffolds at 7 and 14 days of culture. At SEM examination was determined a high porosity of both cross-linked sponges, and thin walls (2-4 µm) with many small cavities in them, through which the pores communicate. However, it is determined that the pores of sponges cross-linked with riboflavin generally have larger sizes (70-220 µm) compared to those cross-linked with GA (50-150 µm) (p <0.01). Also semnificative difference (p <0.01) between pore size was determined in demineralised femoral (25-80 µm) and iliac wing bones (140-520 µm), and with different wall thickness (p <0.01). Conclusions. The obtained scaffolds had a good biocompatibility and a very nonhomogeneous structure

Grefe obținute prin inginerie tisulară în tratamentul defectelor de cartilaj articular

Background. Articular cartilage lesions are common in patients with injuries of large joints. Cartilage defects can lead to the joint osteoarthritis. Mosaicplasty and tissue engineering techniques are used today in the treatment of such lesions. Objective of the study. The in vivo testing of obtained allogeneic demineralized and decellularized osteochondral graft (DDOG), combined with autologous bone marrow mesenchymal stem cells (MSC) and chondrocytes, for articular cartilage repair. Material and Methods. The rabbit distal femurs were demineralised in 0.6M HCl. Pieces of osteochondral tissue with 3.7 mm in diameter were cutted and decellularized in 1% SDS. The autologous MSC (n=7) and chondrocytes (n=7) were isolated and cultured, then seedet on the graft and transplanted in a knee osteochondral defect. In the control group the rabbits were treated by Mosaicplasty technique (n=7). Results. Cartilage regeneration was assessed by the Unicamp Partial Thickness Score (SGPU) at 12 weeks after transplantation. Practically we did not find a significant difference between the group treated with DDOG combined with MSC and the one treated with DDOG combined with chondrocytes even if the first one statistically shows better results (p˃ 0.5). At the same time, there is a significant difference between the results obtained after the treatment with DDOG combined with MSC compared to the control group (p˂ 0.1) and when comparing the group treated with DDOG combined with chondrocytes with the control group (p˂ 0.5). Conclusion. Utilisation of DDOG combined with MSC and chondrocytes is more effective in regeneration of a critical experimental cartilage defect if compared to Mosaicplasty. DDOG with MSC can be implemented in clinical practice because it is one step surgery and does not bring additional trauma to the joint. Introducere. Leziunile de cartilaj articular se întâlnesc frecvent la pacienți cu traumatisme ale articulațiilor mari. Defectele de cartilaj pot duce la degradarea artrozică a articulației. Mosaicplastia şi tehnicile de inginerie tisulară sunt utilizate și azi în tratamentul unor astfel de leziuni. Scopul lucrării. Testarea in vivo a grefei osteocondrale demineralizate şi decelularizate (GOOD) alogene, obţinute prin combinarea cu celule stem mezenchimale de măduvă osoasă (CSM) și condrocite autologe pentru repararea cartilajului articular. Material și Metode. Femure distale de iepure au fost demineralizate în 0.6M HCI. Bucăți de țesut osteochondral cu diametrul de 3.7 mm au fost tăiate și decelularizate în 1% SDS. Au foat izolate și cultivate CSM (n=7) și condrocite (n=7) autologe care apoi au fost fixate pe grefe și implantate în defecte osteochondrale la nivel de genunchi. Drept control au servit iepurii operați prin tehnica de Mosaicplastie (n = 7). Rezultate. Regenerarea cartilajului a fost evaluată prin Scorul de Grosime Parțială Unicamp (SGPU) la 12 săptămâni de la transplantare. Pratic nu am gasit diferență semnificativă între grupul tratat cu GODD combinat cu CSM și cel tratat cu GODD combinat cu condrocite, chiar dacă cel dintâi statistic prezintă rezultate mai bune (p˃ 0.5). Totodată, există o diferență semnificativă între rezultatele obținute după tratamentul cu GODD combinată cu CSM, comparativ cu grupul martor (p˂ 0.1) și la compararea grupului cu GODD combinat cu condrocite cu grupul martor (p˂ 0.5). Concluzii. Utilizarea GODD combinate cu CSM și condrocite sunt mai eficiente în regenerarea defectelor experimentale de cartilaj, comparativ cu Mosaicplastia. Utiizarea GODD cu CSM poate fi aplicată în clinică, deoarece este o intervenție chirurgicală într-un pas și nu aduce traume suplimentare articulației

Phytochemical Profile, Antioxidant Activity, and Cytotoxicity Assessment of Tagetes erecta L. Flowers

Tagetes erecta L. is a popular ornamental plant of the Asteraceae family, which is widely cultivated not only for its decorative use, but also for the extraction of lutein. Besides carotenoid representatives, which have been extensively studied, other important classes of secondary metabolites present in the plant, such as polyphenols, could exhibit important biological activities. The phytochemical analysis of a methanolic extract obtained from T. erecta inflorescences was achieved using liquid chromatography–mass spectrometry (LC-MS) techniques. The extract was further subjected to a multistep purification process, which allowed the separation of different fractions. The total extract and its fractions contain several polyphenolic compounds, such as hydroxybenzoic and hydroxycinnamic acid derivatives, flavonols (especially quercetagetin glycosides), and several aglycons (e.g., quercetin, patuletin). One of the fractions, containing mostly quercetagitrin, was subjected to two different antioxidant assays (metal chelating activity and lipoxygenase inhibition) and to in vitro cytotoxicity assessment. Generally, the biological assays showed promising results for the investigated fraction compared to the initial extract. Given the encouraging outcome of the in vitro assays, further purification and structural analysis of compounds from T. erecta extracts, as well as further in vivo investigations are justified

New ibuprofen derivatives with thiazolidine-4-one scaffold with improved pharmaco-toxicological profile

International audienceBackground Aryl-propionic acid derivatives with ibuprofen as representative drug are very important for therapy, being recommended especially for anti-inflammatory and analgesic effects. On other hand 1,3-thiazolidine-4-one scaffold is an important heterocycle, which is associated with different biological effects such as anti-inflammatory and analgesic, antioxidant, antiviral, antiproliferative, antimicrobial etc. The present study aimed to evaluated the toxicity degree and the anti-inflammatory and analgesic effects of new 1,3-thiazolidine-4-one derivatives of ibuprofen. Methods For evaluation the toxicity degree, cell viability assay using MTT method and acute toxicity assay on rats were applied. The carrageenan-induced paw-edema in rat was used for evaluation of the anti-inflammatory effect while for analgesic effect the tail-flick test, as thermal nociception in rats and the writhing assay, as visceral pain in mice, were used. Results The toxicological screening, in terms of cytotoxicity and toxicity degree on mice, revealed that the ibuprofen derivatives ( 4a-n ) are non-cytotoxic at 2 μg/ml. In addition, ibuprofen derivatives reduced carrageenan-induced paw edema in rats, for most of them the maximum effect was recorded at 4 h after administration which means they have medium action latency, similar to that of ibuprofen. Moreover, for compound 4d the effect was higher than that of ibuprofen, even after 24 h of administration. The analgesic effect evaluation highlighted that 4 h showed increased pain inhibition in reference to ibuprofen in thermal (tail-flick assay) and visceral (writhing assay) nociception models. Conclusions The study revealed for ibuprofen derivatives, noted as 4 m, 4 k, 4e, 4d , a good anti-inflammatory and analgesic effect and also a safer profile compared with ibuprofen. These findings could suggest the promising potential use of them in the treatment of inflammatory pain conditions