The Lyophilization Process Maintains the Chemical and Biological Characteristics of Royal Jelly

The alternative use of natural products, like royal jelly (RJ), may be an important tool for the treatment of infections caused by antibiotic-resistant bacteria. RJ presents a large number of bioactive substances, including antimicrobial compounds. In this study, we carried out the chemical characterization of fresh and lyophilized RJ and investigated their antibacterial effects with the purpose of evaluating if the lyophilization process maintains the chemical and antibacterial properties of RJ. Furthermore, we evaluated the antibacterial efficacy of the main fatty acid found in RJ, the 10-hydroxy-2-decenoic acid (10H2DA). Chromatographic profile of the RJ samples showed similar fingerprints and the presence of 10H2DA in both samples. Furthermore, fresh and lyophilized RJ were effective against all bacteria evaluated; that is, the lyophilization process maintains the antibacterial activity of RJ and the chemical field of 10H2DA. The fatty acid 10H2DA exhibited a good antibacterial activity against Streptococcus pneumoniae. Therefore, it may be used as an alternative and complementary treatment for infections caused by antibiotic-resistant S. pneumoniae

Investigation of different sources of bone marrow mesenchymal stem cells and biomaterials for the generation of functional humanized ossicles in vivo

O nicho hematopoiético fornece um microambiente adequado para as células-tronco hematopoiéticas (CTHs) residirem, e é responsável pelo destino destas células quanto à quiescência, autorrenovação e diferenciação. Neste nicho, diferentes tipos celulares (células endoteliais, estromais, osteoblastos, entre outros), fatores solúveis e concentração de oxigênio cooperam para dar suporte às CTHs e hematopoese. Pouco é conhecido sobre a identidade dos tipos celulares que compõem o microambiente hematopoiético in vivo. Sabe-se que células-tronco mesenquimais (CTMs) são capazes de dar suporte às CTHs. As CTMs são definidas como uma população clonogênica, multipotente, podendo se diferenciar ex vivo em células da linhagem mesenquimal. Embora encontradas em vários tecidos, elas foram primeiramente isoladas da medula óssea (MO), onde estão presentes em diferentes compartimentos do nicho medular, podendo ser encontradas na região perivascular da MO bem como próxima ao endósteo. Sendo assim, as CTMs residentes no nicho hematopoiético podem representar duas populações com características distintas para dar suporte às CTHs durante a hematopoese. Nas últimas décadas, diferentes tipos celulares têm sido cultivados em cultivo 3D com biomateriais/scaffolds e implantados in vivo visando a geração de modelos de organoides (micro tecidos) a fim de recapitular o comportamento destes tecidos para estudos de morfogênese e função. Portanto, é relevante adaptar o cultivo de CTMs humanas em biomateriais que mimetizam a estrutura do microambiente da CTH in vivo, e induzir a formação de um ossículo humanizado (hOss) contendo nicho heterotópico in vivo para recapitular um microambiente de MO humanizado. Este tipo de modelo permite melhorar o cenário dos estudos de xenotransplante com células hematopoiéticas sadias e malignas. Assim, este trabalho tem como objetivo produzir um hOss heterotópico a partir de CTMs humanas da MO e osso esponjoso cultivadas com células endoteliais e biomateriais osteocondutores. Tal conhecimento proporcionará entender a regulação das CTHs mediada pelo nicho, podendo, futuramente, ajudar no melhoramento das respostas clínicas dos transplantes de MO.The hematopoietic niche provides a suitable microenvironment for hematopoietic stem cells (HSC) to reside, and is responsible for the fate of these cells in terms of quiescence, self-renewal and differentiation. In the niche, different cell types (endothelial, stromal, osteoblast cells, among others), soluble factors and oxygen concentration cooperate to support HSC and hematopoiesis. Little is known about the identity of the cell types that make up the hematopoietic microenvironment in vivo. It is known that mesenchymal stem cells (MSC) are capable of supporting HSC. MSC are defined as a clonogenic, multipotent population that can differentiate ex vivo into mesenchymal lineage cells. Although found in several tissues, they were first isolated from the bone marrow (BM), where they are present in different compartments of the medullary niche, and can also be found in the perivascular region of the BM as well as close to the endosteum. Therefore, MSC residing in the hematopoietic niche may represent two populations with distinct characteristics to support HSC during hematopoiesis. In recent decades, different cell types have been cultivated in 3D culture with biomaterials/scaffolds and implanted in vivo aiming at the generation of organoid models (micro tissues) in order to recapitulate the behavior of these tissues for studies of morphogenesis and function. Therefore, it is relevant to adapt the cultivation of human MSC in biomaterials that mimic the structure of the HSC microenvironment in vivo, and induce the formation of a humanized ossicle (hOss) containing heterotopic niche in vivo to recapitulate a humanized BM microenvironment. This kind of model improves the scenario of xenotransplantation studies of healthy and malignant hematopoietic cells. Thus, this work aims to produce a heterotopic hOss from human MSC from BM and trabecular bone cultivated with endothelial cells and osteoconductive biomaterials. Such knowledge will provide an understanding of the niche-mediated regulation of HSC, which may help, in the future, to improve the clinical responses of BM transplants

The Lyophilization Process Maintains the Chemical and Biological Characteristics of Royal Jelly

The alternative use of natural products, like royal jelly (RJ), may be an important tool for the treatment of infections caused by antibiotic-resistant bacteria. RJ presents a large number of bioactive substances, including antimicrobial compounds. In this study, we carried out the chemical characterization of fresh and lyophilized RJ and investigated their antibacterial effects with the purpose of evaluating if the lyophilization process maintains the chemical and antibacterial properties of RJ. Furthermore, we evaluated the antibacterial efficacy of the main fatty acid found in RJ, the 10-hydroxy-2-decenoic acid (10H2DA). Chromatographic profile of the RJ samples showed similar fingerprints and the presence of 10H2DA in both samples. Furthermore, fresh and lyophilized RJ were effective against all bacteria evaluated; that is, the lyophilization process maintains the antibacterial activity of RJ and the chemical field of 10H2DA. The fatty acid 10H2DA exhibited a good antibacterial activity against Streptococcus pneumoniae. Therefore, it may be used as an alternative and complementary treatment for infections caused by antibiotic-resistant S. pneumoniae

Endothelial Cells Tissue-Specific Origins Affects Their Responsiveness to TGF-β2 during Endothelial-to-Mesenchymal Transition

The endothelial-to-mesenchymal transition (EndMT) is a biological process where endothelial cells (ECs) acquire a fibroblastic phenotype after concomitant loss of the apical-basal polarity and intercellular junction proteins. This process is critical to embryonic development and is involved in diseases such as fibrosis and tumor progression. The signaling pathway of the transforming growth factor β (TGF-β) is an important molecular route responsible for EndMT activation. However, it is unclear whether the anatomic location of endothelial cells influences the activation of molecular pathways responsible for EndMT induction. Our study investigated the molecular mechanisms and signaling pathways involved in EndMT induced by TGF-β2 in macrovascular ECs obtained from different sources. For this purpose, we used four types of endothelial cells (coronary artery endothelial cells, CAECs; primary aortic endothelial cells PAECs; human umbilical vein endothelia cells, HUVECs; and human pulmonary artery endothelial cells, HPAECs) and stimulated with 10 ng/mL of TGF-β2. We observed that among the ECs analyzed in this study, PAECs showed the best response to the TGF-β2 treatment, displaying phenotypic changes such as loss of endothelial marker and acquisition of mesenchymal markers, which are consistent with the EndMT activation. Moreover, the PAECs phenotypic transition was probably triggered by the extracellular signal⁻regulated kinases 1/2 (ERK1/2) signaling pathway activation. Therefore, the anatomical origin of ECs influences their ability to undergo EndMT and the selective inhibition of the ERK pathway may suppress or reverse the progression of diseases caused or aggravated by the involvement EndMT activation