Study of the fetal and maternal microbiota in pregnant women with intrauterine growth restriction and its relationship with inflammatory biomarkers: A case-control study protocol (SPIRIT compliant)

In general terms, fetal growth restriction (FGR) is considered the impossibility of achieving the genetically determined potential size. In the vast majority of cases, it is related to uteroplacental insufficiency. Although its origin remains unknown and causes are only known in 30% of cases, it is believed to be related to an interaction of environmental and genetic factors with either a fetal or maternal origin. One hypothesis is that alterations in the gastrointestinal microbiota composition, and thus alteration in the immune response, could play a role in FGR development. We performed an observational, prospective study in a subpopulation affected with FGR to elucidate the implications of this microbiota on the FGR condition. A total of 63 fetuses with FGR diagnosed in the third trimester as defined by the Delphi consensus, and 63 fetuses with fetal growth appropriate for gestational age will be recruited. Obstetric and nutritional information will be registered by means of specific questionnaires. We will collect maternal fecal samples between 30 to 36 weeks, intrapartum samples (maternal feces, maternal and cord blood) and postpartum samples (meconium and new-born feces at 6 weeks of life). Samples will be analyzed in the Department of Biochemistry and Molecular Biology II, Nutrition and Food Technology Institute of the University of Granada (UGR), for the determination of the gastrointestinal microbiota composition and its relationship with inflammatory biomarkers. This study will contribute to a better understanding of the influence of gastrointestinal microbiota and related inflammatory biomarkers in the development of FGR. Trial registration: NCT04047966. Registered August 7, 2019, during the recruitment stage. Retrospectively registered. Ongoing research. Keywords: fetal growth restriction, gastrointestinal microbiota, inflammatory biomarker

Biological Effects of Maslinic Acid on Human Epithelial Cells Used in Tissue Engineering

In the present work, we evaluated the potential of maslinic acid (MA) to improve currently available keratinocyte culture methods for use in skin tissue engineering. Results showed that MA can increase cell proliferation and WST-1 activity of human keratinocytes after 24, 48, and 72 h, especially at the concentration of 5 μg/ml, without affecting cell viability. This effect was associated to a significant increase of KI-67 protein expression and upregulation of several genes associated to cell proliferation (PCNA) and differentiation (cytokeratins, intercellular junctions and basement membrane related genes). When human keratinocytes were isolated from skin biopsies, we found that MA at the concentration of 5 μg/ml significantly increased the efficiency of the explant and the cell dissociation methods. These results revealed the positive effects of MA to optimize human keratinocyte culture protocols for use in skin tissue engineering.PE-0395-2019 Consejería de Salud y Familias, Junta de Andalucía, SpainB-CTS-450-UGR20 (proyectos de I + D + i en el marco del Programa Operativo FEDER Andalucía 2014-2020, Universidad de Granada and Consejería de Transformación Económica, Industria, Conocimiento y Universidades)Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I + D + i) of the Spanish Ministry of Science and Innovation through grants FIS PI20/0317, FIS PI21/ 0980 and ICI19-00024 (BIOCLEFT) from Instituto de Salud Carlos III, co-financed by the European Regional Development Fun

Fibrin and Marine-Derived Agaroses for the Generation of Human Bioartificial Tissues: An Ex Vivo and In Vivo Study

Development of an ideal biomaterial for clinical use is one of the main objectives of current research in tissue engineering. Marine-origin polysaccharides, in particular agaroses, have been widely explored as scaffolds for tissue engineering. We previously developed a biomaterial based on a combination of agarose with fibrin, that was successfully translated to clinical practice. However, in search of novel biomaterials with improved physical and biological properties, we have now generated new fibrin-agarose (FA) biomaterials using 5 different types of agaroses at 4 different concentrations. First, we evaluated the cytotoxic effects and the biomechanical properties of these biomaterials. Then, each bioartificial tissue was grafted in vivo and histological, histochemical and immunohistochemical analyses were performed after 30 days. Ex vivo evaluation showed high biocompatibility and differences in their biomechanical properties. In vivo, FA tissues were biocompatible at the systemic and local levels, and histological analyses showed that biointegration was associated to a pro-regenerative process with M2-type CD206-positive macrophages. These results confirm the biocompatibility of FA biomaterials and support their clinical use for the generation of human tissues by tissue engineering, with the possibility of selecting specific agarose types and concentrations for applications requiring precise biomechanical properties and in vivo reabsorption times.Hispanagar SA, Burgos, Spain, through CDTI, Ministry of Science and Innovation, Spain, Programa Operativo Plurirregional de Crecimiento Inteligente (CRIN) IDI-20180052Spanish Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I + D + I) of the Spanish Ministry of Science and Innovation (Instituto de Salud Carlos III) FIS PI20/0317 FIS PI20/0318 FIS PI21/0980 ICI19/00024 ICI21/00010Junta de Andalucia PE-0395-2019 PI-0442-2019 PI-0086-2020Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades B-CTS-504-UGR2

Study of the fetal and maternal microbiota in pregnant women with intrauterine growth restriction and its relationship with inflammatory biomarkers A case-control study protocol (SPIRIT compliant)

In general terms, fetal growth restriction (FGR) is considered the impossibility of achieving the genetically determined potential size. In the vast majority of cases, it is related to uteroplacental insufficiency. Although its origin remains unknown and causes are only known in 30% of cases, it is believed to be related to an interaction of environmental and genetic factors with either a fetal or maternal origin. One hypothesis is that alterations in the gastrointestinal microbiota composition, and thus alteration in the immune response, could play a role in FGR development. We performed an observational, prospective study in a subpopulation affected with FGR to elucidate the implications of this microbiota on the FGR condition. A total of 63 fetuses with FGR diagnosed in the third trimester as defined by the Delphi consensus, and 63 fetuses with fetal growth appropriate for gestational age will be recruited. Obstetric and nutritional information will be registered by means of specific questionnaires. We will collect maternal fecal samples between 30 to 36 weeks, intrapartum samples (maternal feces, maternal and cord blood) and postpartum samples (meconium and new-born feces at 6 weeks of life). Samples will be analyzed in the Department of Biochemistry and Molecular Biology II, Nutrition and Food Technology Institute of the University of Granada (UGR), for the determination of the gastrointestinal microbiota composition and its relationship with inflammatory biomarkers. This study will contribute to a better understanding of the influence of gastrointestinal microbiota and related inflammatory biomarkers in the development of FGR. Trial registration: NCT04047966. Registered August 7, 2019, during the recruitment stage. Retrospectively registered. Ongoing research.Instituto de Salud Calos IIIFondos de Desarrollo Regional Europeos (FEDER) PI17/0121

Evaluation of Marine Agarose Biomaterials for Tissue Engineering Applications

Five agarose types (D1LE, D2LE, LM, MS8 and D5) were evaluated in tissue engineering and compared for the first time using an array of analysis methods. Acellular and cellular constructs were generated from 0.3–3%, and their biomechanical properties, in vivo biocompatibility (as determined by LIVE/DEAD, WST-1 and DNA release, with n = 6 per sample) and in vivo biocompatibility (by hematological and biochemical analyses and histology, with n = 4 animals per agarose type) were analyzed. Results revealed that the biomechanical properties of each hydrogel were related to the agarose concentration (p < 0.001). Regarding the agarose type, the highest (p < 0.001) Young modulus, stress at fracture and break load were D1LE, D2LE and D5, whereas the strain at fracture was higher in D5 and MS8 at 3% (p < 0.05). All agaroses showed high biocompatibility on human skin cells, especially in indirect contact, with a correlation with agarose concentration (p = 0.0074 for LIVE/DEAD and p = 0.0014 for WST-1) and type, although cell function tended to decrease in direct contact with highly concentrated agaroses. All agaroses were safe in vivo, with no systemic effects as determined by hematological and biochemical analysis and histology of major organs. Locally, implants were partially encapsulated and a pro-regenerative response with abundant M2- type macrophages was found. In summary, we may state that all these agarose types can be safely used in tissue engineering and that the biomechanical properties and biocompatibility were strongly associated to the agarose concentration in the hydrogel and partially associated to the agarose type. These results open the door to the generation of specific agarose-based hydrogels for definite clinical applications such as the human skin, cornea or oral mucosa.Hispanagar SA, Burgos, Spain, through CDTI, Ministry of Science and Innovation, Spain, Programa Operativo Plurirregional de Crecimiento Inteligente (CRIN) IDI-20180052ISCIII thorough AES AC17/00013Junta de Andalucía PE-0395-2019Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+i) from Ministerio de Ciencia, Innovación y Universidades (Instituto de Salud Carlos III) FIS PI17/0391Fondo Europeo de Desarrollo Regional ERDF-FEDER, European Union PI20/031

Optimization of human skin keratinocyte culture protocols using bioactive molecules derived from olive oil

Skin damage due to severe burns can compromise patient life. Current tissue engineering methods allow the generation of human skin substitutes for clinical use. However, this process is time-consuming, as the keratinocytes required to generate artificial skin have a low proliferation rate in culture. In this study, we evaluated the pro-proliferative effects of three natural biomolecules isolated from olive oil: phenolic extract (PE), DL-3,4-dihydroxyphenyl glycol (DHFG), and oleuropein (OLP), on cultured human skin keratinocytes. The results showed that PE and OLP increased the proliferation of immortalized human skin keratinocytes, especially at concentrations of 10 and 5 µg/mL, respectively, without altering cell viability. In contrast, DHFG did not produce a significant improvement in keratinocyte proliferation. In normal human skin keratinocytes obtained from skin biopsies, we found that PE, but not OLP, could increase the number of keratinocyte colonies and the area occupied by these cells. Furthermore, this effect was associated with increased KI-67 and Proliferating cell nuclear antigen (PCNA) gene expression. Thus, we propose that PE positively affects keratinocyte proliferation and could be used in culture protocols to improve bioartificial skin generation by tissue engineering

Generation and Evaluation of Novel Biomaterials Based on Decellularized Sturgeon Cartilage for Use in Tissue Engineering

Because cartilage has limited regenerative capability, a fully efficient advanced therapy medicinal product is needed to treat severe cartilage damage. We evaluated a novel biomaterial obtained by decellularizing sturgeon chondral endoskeleton tissue for use in cartilage tissue engineering. In silico analysis suggested high homology between human and sturgeon collagen proteins, and ultra-performance liquid chromatography confirmed that both types of cartilage consisted mainly of the same amino acids. Decellularized sturgeon cartilage was recellularized with human chondrocytes and four types of human mesenchymal stem cells (MSC) and their suitability for generating a cartilage substitute was assessed ex vivo and in vivo. The results supported the biocompatibility of the novel scaffold, as well as its ability to sustain cell adhesion, proliferation and differentiation. In vivo assays showed that the MSC cells in grafted cartilage disks were biosynthetically active and able to remodel the extracellular matrix of cartilage substitutes, with the production of type II collagen and other relevant components, especially when adipose tissue MSC were used. In addition, these cartilage substitutes triggered a pro-regenerative reaction mediated by CD206- positive M2 macrophages. These preliminary results warrant further research to characterize in greater detail the potential clinical translation of these novel cartilage substitutes.Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+i) of the Spanish Ministry of Economy and Competitiveness (Instituto de Salud Carlos III), Grant FIS PI20/0317FEDER funds (European Union)Consejería de Salud y Familias, Junta de Andalucía, Spain - PI-0257-201

Evaluation of Marine Agarose Biomaterials for Tissue Engineering Applications

Five agarose types (D1LE, D2LE, LM, MS8 and D5) were evaluated in tissue engineering and compared for the first time using an array of analysis methods. Acellular and cellular constructs were generated from 0.3-3%, and their biomechanical properties, in vivo biocompatibility (as determined by LIVE/DEAD, WST-1 and DNA release, with n = 6 per sample) and in vivo biocompatibility (by hematological and biochemical analyses and histology, with n = 4 animals per agarose type) were analyzed. Results revealed that the biomechanical properties of each hydrogel were related to the agarose concentration (p < 0.001). Regarding the agarose type, the highest (p < 0.001) Young modulus, stress at fracture and break load were D1LE, D2LE and D5, whereas the strain at fracture was higher in D5 and MS8 at 3% (p < 0.05). All agaroses showed high biocompatibility on human skin cells, especially in indirect contact, with a correlation with agarose concentration (p = 0.0074 for LIVE/DEAD and p = 0.0014 for WST-1) and type, although cell function tended to decrease in direct contact with highly concentrated agaroses. All agaroses were safe in vivo, with no systemic effects as determined by hematological and biochemical analysis and histology of major organs. Locally, implants were partially encapsulated and a pro-regenerative response with abundant M2-type macrophages was found. In summary, we may state that all these agarose types can be safely used in tissue engineering and that the biomechanical properties and biocompatibility were strongly associated to the agarose concentration in the hydrogel and partially associated to the agarose type. These results open the door to the generation of specific agarose-based hydrogels for definite clinical applications such as the human skin, cornea or oral mucosa.This research was funded by grant IDI-20180052 (Agarmatriz), leaded by Hispanagar SA, Burgos, Spain, through CDTI, Ministry of Science and Innovation, Spain, Programa Operativo Plurirregional de Crecimiento Inteligente (CRIN); award no. AC17/00013 (NanoGSkin project) by ISCIII thorough AES 2017 within the EuroNanoMed framework; grant PE-0395-2019 from Consejería de Salud y Familias, Junta de Andalucía, Spain; and by the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (I+D+i) from Ministerio de Ciencia, Innovación y Universidades (Instituto de Salud Carlos III), grants FIS PI17/0391, and PI20/0317 (co-financed by Fondo Europeo de Desarrollo Regional ERDF-FEDER, European Union).Ye