Evolutionary anatomical and functional characteristics of the intrinsic shoulder and brachial muscles in the northern anteater (Tamandua mexicana).

Tamandua mexicana is an anteater species native from Mexico to Peru. This species is of great evolutionary interest because it belongs to one of the oldest clades of placental mammals in the American continent. This study aimed to describe the origin, insertion, and arterial supply of the intrinsic shoulder and brachial muscles of T. mexicana. We also compared the masses of the functional groups. Gross dissections were performed on both thoracic limbs of 13 cadavers. ANOVA followed by Tukey's test was used for statistical analyses. The subscapularis muscle presents a hiatus to the common tendon of the caput breve of the biceps brachii and coracobrachialis muscles. A variant accessory muscle, the m. articularis humeri lateralis, was found on the lateral surface of the shoulder joint. M. deltoideus pars acromialis has two bellies. The teres major muscle is perforated by the aponeurotic origin of the m. tensor fasciae antebrachii. The triceps brachii has two capita longi. The caput mediale is fused with the m. anconeus medialis. The caput laterale can have an accessory belly as an anatomical variant. Among the functional groups, a significant difference was found between the elbow extensors and flexors, with the latter having the lowest mass. In conclusion, the intrinsic muscles of T. mexicana presented unique features for the species, as well as arrangements in mass distribution that evidence a possible evolutionary convergence among species of the Superorder Xenarthra.

Three-Dimensional Printing of Graphene Oxide/Poly-L-Lactic Acid Scaffolds Using Fischer-Koch Modeling.

Accurately printing customizable scaffolds is a challenging task because of the complexity of bone tissue composition, organization, and mechanical behavior. Graphene oxide (GO) and poly-L-lactic acid (PLLA) have drawn attention in the field of bone regeneration. However, as far as we know, the Fischer-Koch model of the GO/PLLA association for three-dimensional (3D) printing was not previously reported. This study characterizes the properties of GO/PLLA-printed scaffolds in order to achieve reproducibility of the trabecula, from virtual planning to the printed piece, as well as its response to a cell viability assay. Fourier-transform infrared and Raman spectroscopy were performed to evaluate the physicochemical properties of the nanocomposites. Cellular adhesion, proliferation, and growth on the nanocomposites were evaluated using scanning electron microscopy. Cell viability tests revealed no significant differences among different trabeculae and cell types, indicating that these nanocomposites were not cytotoxic. The Fischer Koch modeling yielded satisfactory results and can thus be used in studies directed at diverse medical applications, including bone tissue engineering and implants.

Placental scaffolds as a potential biological platform for embryonic stem cells differentiation into hepatic-like cells lineage: A pilot study.

Hepatic microenvironment plays an essential role in liver regeneration, providing the necessary conditions for cell proliferation, differentiation and tissue rearrangement. One of the key factors for hepatic tissue reconstruction is the extracellular matrix (ECM), which through collagenous and non-collagenous proteins provide a three-dimensional structure that confers support for cell adhesion and assists on their survival and maintenance. In this scenario, placental ECM may be eligible for hepatic tissue reconstruction, once these scaffolds hold the major components required for cell support. Therefore, this preliminary study aimed to access the possibility of mouse embryonic stem cells differentiation into hepatocyte-like cells on placental scaffolds in a three-dimensional dynamic system using a Rotary Cell Culture System. Following a four-phase differentiation protocol that simulates liver embryonic development events, the preliminary results showed that a significant quantity of cells adhered and interacted with the scaffold through outer and inner surfaces. Positive immunolabelling for alpha fetus protein and CK7 suggest presence of hepatoblast phenotype cells, and CK18 and Albumin positive immunolabelling suggest the presence of hepatocyte-like phenotype cells, demonstrating the presence of a heterogeneous population into the recellularized scaffolds. Periodic Acid Schiff-Diastase staining confirmed the presence of glycogen storage, indicating that differentiate cells acquired a hepatic-like phenotype. In conclusion, these preliminary results suggested that mouse placental scaffolds might be used as a biological platform for stem cells differentiation into hepatic-like cells and their establishment, which may be a promissing biomaterial for hepatic tissue reconstruction.

Perfusion and Ultrasonication Produce a Decellularized Porcine Whole-Ovary Scaffold with a Preserved Microarchitecture.

The application of decellularized scaffolds for artificial tissue reconstruction has been an approach with great therapeutic potential in regenerative medicine. Recently, biomimetic ovarian tissue reconstruction was proposed to reestablish ovarian endocrine functions. Despite many decellularization methods proposed, there is no established protocol for whole ovaries by detergent perfusion that is able to preserve tissue macro and microstructure with higher efficiency. This generated biomaterial may have the potential to be applied for other purposes beyond reproduction and be translated to other areas in the tissue engineering field. Therefore, this study aimed to establish and standardize a protocol for porcine ovaries' decellularization based on detergent perfusion and ultrasonication to obtain functional whole-ovary scaffolds. For that, porcine ovaries (n = 5) were perfused with detergents (0.5% SDS and 1% Triton X-100) and submitted to an ultrasonication bath to produce acellular scaffolds. The decellularization efficiency was evaluated by DAPI staining and total genomic DNA quantification. ECM morphological evaluation was performed by histological, immunohistochemistry, and ultrastructural analyses. ECM physico-chemical composition was evaluated using FTIR and Raman spectroscopy. A cytocompatibility and cell adhesion assay using murine fibroblasts was performed. Results showed that the proposed method was able to remove cellular components efficiently. There was no significant ECM component loss in relation to native tissue, and the scaffolds were cytocompatible and allowed cell attachment. In conclusion, the proposed decellularization protocol produced whole-ovaries scaffolds with preserved ECM composition and great potential for application in tissue engineering.

Calotropis procera (Aiton) Dryand (Apocynaceae): State of the art of its uses and Applications.

Calotropis procera (Aiton) Dryand (Apocynaceae), popularly known as milkweed, has been traditionally used to treat diseases particularly associated with gastric disorders, skin disease and inflammatory processes. The present study aimed to review the current scientific evidence regarding the pharmacological effects of C. procera extracted phytochemicals and possible research opportunities as complementary and alternative medicine. Scientific publications were searched in various electronic databases (PubMed, Scopus, Web of Science, Google Scholar, Springer, Wiley, and Mendeley) using the following search terms: Calotropis procera, medicinal plants, toxicity, phytochemical characterization, and biological effects. Collected data showed that cardenolides, steroid glycoside and flavonoids are the main classes of phytochemicals identified in C. procera latex and leaves. In addition, lignans, terpenes, coumarins, and phenolic acids have been reported. These metabolites have been correlated with their biological activities, including mainly antioxidant, anti-inflammatory, antitumoral, hypoglycemic, gastric protective, anti-microbial, insecticide, anti-fungal, anti-parasitic, among others. However, some of the studies were carried out with only a single dose or with a high dose not achievable under physiological conditions. Therefore, the validity of C. procera biological activity may be questionable. Not less important to highlight are the risks associated with its use and the possibility of accumulation of heavy metals that can be toxic. Furthermore, there are no clinical trials with C. procera to date. In conclusion, the need of bioassayguided isolation of bioactive compounds, bioavailability and efficacy, as well as pharmacological and toxicity studies, are needed using in vivo models and clinical trials in order to support the traditionally claimed health benefits.

Term alpaca placenta glycosylation profile and its correlation with pregnancy maintenance and fetal survival.

Alpaca is a South American camelid, particularly present in Peruvian highlands, where oxygen concentration and atmospheric pressure are very low. Due to this fact, gestational physiology has adapted to preserve the conceptus' and mother's health. In this context, several cellular and molecular features play an essential role during and at the end of gestation. Structural carbohydrates act on maternal-fetal communication, recognize exogenous molecules, and contribute to placental barrier selectivity. Therefore, this study aimed to characterize the structural carbohydrate profiles that are present in the term alpaca placenta, kept in their natural habitat of around 4,000 m height. For this propose, 12 term alpaca placentas were collected, and the material was obtained at the time of birth from camelids raised naturally in the Peruvian highlands, in the Cusco region. All placenta samples were processed for histological analysis. A lectin histochemical investigation was performed using 13 biotinylated lectins, allowing us to determine the location of carbohydrates and their intensity on a semi-quantitative scale. Our results demonstrated that during term gestation, the epitheliochorial alpaca placenta shows a high presence of carbohydrates, particularly glucose, α-linked mannose, N-acetylglucosamine ß (GlcNAc), galactose (αGal), and N-acetylgalactosamine α (GalNAc), present in the trophoblast, amnion epithelium, and mesenchyme, as well as the presence of sialic acid residues and low affinity for fucose. In fetal blood capillaries, the presence of bi- and tri-antennary complex structures and α-linked mannose was predominated. In conclusion, we characterized the glycosylation profile in the term alpaca placenta. Based on our data, compared to those reported in the bibliography, we suggest that these carbohydrates could participate in the labor of these animals that survive in Peruvian extreme environments.

Decellularized Vascular Scaffolds Derived from Bovine Placenta Blood Vessels. / Scaffolds Vasculares Descelularizados Provenientes de Vasos Sanguíneos de Placenta Bovina.

OBJECTIVES: Diseases associated with the circulatory system are the main causes of worldwide morbidity and mortality, implying the need for vascular implants. Thus, the production of vascular biomaterials has proven to be a promising alternative to therapies used in studies and research related to vascular physiology. The present project aims to achieve the artificial development of blood vessels through the recellularization of vascular scaffolds derived from bovine placental vessels. METHODS: The chorioallantoic surface of the bovine placenta was used to produce decellularized biomaterials. For recellularization, 2.5 x 104 endothelial cells were seeded above each decellularized vessel fragment during three or seven days, when culture were interrupted, and the fragments were fixed for cell attachment analysis. Decellularized and recellularized biomaterials were evaluated by basic histology, scanning electron microscopy, and immunohistochemistry. RESULTS: The decellularization process produced vessels that maintained natural structure and elastin content, and no cells or gDNA remains were observed. Endothelial precursor cells were also attached to lumen and external surface of the decellularized vessel.Conclusion: Our results show a possibility of future uses of this biomaterial in cardiovascular medicine, as in the development of engineered vessels.

FUNDAMENTO: As doenças associadas ao aparelho circulatório são as principais causas de morbidade e mortalidade em todo o mundo, implicando a necessidade de implantes vasculares. Assim, a produção de biomateriais vasculares tem se mostrado uma alternativa promissora às terapias utilizadas em estudos e pesquisas relacionados à fisiologia vascular. OBJETIVOS: O presente projeto visa ao desenvolvimento artificial de vasos sanguíneos pela recelularização de scaffolds vasculares derivados de vasos placentários bovinos. MÉTODOS: A superfície corioalantoide da placenta bovina foi utilizada para produzir biomateriais descelularizados. Para a recelularização, 2,5 x 104 células endoteliais foram semeadas acima de cada fragmento de vaso descelularizado durante três ou sete dias, quando a cultura foi interrompida e os fragmentos foram fixados para análise de adesão celular. Biomateriais descelularizados e recelularizados foram avaliados por histologia básica, microscopia eletrônica de varredura e imuno-histoquímica. RESULTADOS: o processo de descelularização produziu vasos que mantiveram a estrutura natural e o conteúdo de elastina, e não foram observadas células e gDNA remanescentes. Além disso, células precursoras endoteliais se ligaram ao lúmen e à superfície externa do vaso descelularizado. CONCLUSÃO: nossos resultados mostram a possibilidade de usos futuros desse biomaterial na medicina cardiovascular, como, por exemplo, no desenvolvimento de vasos artificiais.

Immunofluorescence Analysis of Estrogen and Progesterone Receptors and Ki-67 Nuclear Protein in Canine Uteri Treated with Medroxyprogesterone Acetate During Anestrus / Análisis de Inmunofluorescencia de Receptores de Estrógeno y Progesterona y Proteína Nuclear Ki-67 en Úteros Caninos Tratados con Acetato de Medroxiprogesterona Durante el Anestr

SUMMARY: Estradiol and progesterone receptors play an essential role in the changes occurring in the uterus during the estrus cycle in dogs (Canis lupus familiaris). In order to investigate the potential effect of progestational agent medroxyprogesterone acetate (MPA) when is used during anestrus on the expression of estradiol receptors [ER], progesterone receptors [PR] and nuclear protein Ki67, we evaluated uterine tissue immunohistochemically. Uteri were grouped as nulliparous (control, n=11), multiparous (n=11) and treated with MPA (n=11; nulliparous with two treatments; 5mg/kg; i.m.). The amount and location of PR, ER and Ki67 were studied on the epithelial surface, apical and basal regions of the endometrium and myometrium using immunohistochemical techniques with a spectral confocal microscope and analyzed by ANOVA. Differences in ER were observed between the multiparous and MPA-treated groups in the apical region of the endometrium (p=0.0022). Differences in cell proliferation were detected between the nulliparous and multiparous groups (p=0.0037) and nulliparous and MPA-treated groups (p=0.0003) in the basal region of the endometrium. In conclusion, two doses of MPA (5mg/kg; i.m.) do not have a significant effect on the expression of ER and PR; however, they inhibit cell proliferation in the basal region of the endometrium, which includes the stroma, subepithelial cell layer, compact layer, and spongy layer. The clinical and long-term effect of this treatment should be evaluated in subsequent studies.

Los receptores de estradiol y progesterona juegan un rol fundamental en los cambios que se producen en el útero durante el ciclo estral de las perras (Canis lupus familiaris). El objetivo de este estudio fue evaluar las expresiones de ER-a y PR en el útero y la proliferación de células endometriales detectando la expresión nuclear de la proteína Ki67 en perras expuestas a la progestina sintética MPA y compararlas con perras nulíparas y multíparas expuestas a progesterona luteal. Úteros fueron agrupados como nulíparas (control, n=11), multíparas (n=11) y tratadas con MPA (n=11; nulíparas con dos tratamientos; 5 mg/kg; i.m.). La expresión de PR, ER-a y Ki67 fue evaluada en la regiones apicales y basales del endometrio y miometrio con un microscopio confocal espectral. Se observó diferencias en ER-a entre los grupos multíparas y tratados con MPA en la región apical del endometrio (p=0,0022). Se detectaron diferencias en la proliferación celular entre los grupos de nulíparas y multíparas (p=0,0037) y los grupos de nulíparas y tratados con MPA (p=0,0003) en la región basal del endometrio. En conclusión, dos dosis de MPA (5mg/kg; i.m.) no tienen un efecto significativo sobre la expresión de ER y PR; sin embargo, inhiben la proliferación celular en la región basal del endometrio, el cual incluye a estroma, capa de células subepiteliales, estratos compacto y esponjoso. El efecto clínico a largo plazo de este tratamiento debe ser evaluado en estudios posteriores.

Biomaterials for Testicular Bioengineering: How far have we come and where do we have to go?

Traditional therapeutic interventions aim to restore male fertile potential or preserve sperm viability in severe cases, such as semen cryopreservation, testicular tissue, germ cell transplantation and testicular graft. However, these techniques demonstrate several methodological, clinical, and biological limitations, that impact in their results. In this scenario, reproductive medicine has sought biotechnological alternatives applied for infertility treatment, or to improve gamete preservation and thus increase reproductive rates in vitro and in vivo. One of the main approaches employed is the biomimetic testicular tissue reconstruction, which uses tissue-engineering principles and methodologies. This strategy pursues to mimic the testicular microenvironment, simulating physiological conditions. Such approach allows male gametes maintenance in culture or produce viable grafts that can be transplanted and restore reproductive functions. In this context, the application of several biomaterials have been proposed to be used in artificial biological systems. From synthetic polymers to decellularized matrixes, each biomaterial has advantages and disadvantages regarding its application in cell culture and tissue reconstruction. Therefore, the present review aims to list the progress that has been made and the continued challenges facing testicular regenerative medicine and the preservation of male reproductive capacity, based on the development of tissue bioengineering approaches for testicular tissue microenvironment reconstruction.

Embryonic-placental relationship in Lagostomus maximus as compared to other hystricognath rodents and eutherian mammals.

Reproductive specializations in caviomorphs (infraorder Hystricognathi), are very peculiar within the Order Rodentia. These include long gestations, the birth of offspring with an extreme degree of precociality, and short lactation periods. This study describes the embryo-placental relationship of viable implantation sites (IS) of the plains viscacha, Lagostomus maximus, after 46 post-coital days. The observations recorded in this study are comparatively discussed with those of other hystricognaths and eutherians. At this stage, the embryo resembles that of other eutherians. At this time of embryo development, the placenta exhibits a size, shape, and organization similar to that it will have in its mature state. Besides, the subplacenta is already highly folded. These characteristics are adequate to sustain the development of future precocial offspring. The mesoplacenta, a structure present in other hystricognaths and related to uterine regeneration is described for the first time in this species. This detailed description of the placental and embryonic structure contributes to the knowledge of the reproductive and developmental biology of the viscacha, as well as that of hystricognaths. These characteristics will allow testing other hypotheses related to the morphology and physiology of the placenta and subplacenta, and their relationship with the growth and development of precocial offspring in Hystricognathi.

The Canine Pancreatic Extracellular Matrix in Diabetes Mellitus and Pancreatitis: Its Essential Role and Therapeutic Perspective.

Diabetes mellitus and pancreatitis are common pancreatic diseases in dogs, affecting the endocrine and exocrine portions of the organ. Dogs have a significant role in the history of research related to genetic diseases, being considered potential models for the study of human diseases. This review discusses the importance of using the extracellular matrix of the canine pancreas as a model for the study of diabetes mellitus and pancreatitis, in addition to focusing on the importance of using extracellular matrix in new regenerative techniques, such as decellularization and recellularization. Unlike humans, rabbits, mice, and pigs, there are no reports in the literature characterizing the healthy pancreatic extracellular matrix in dogs, in addition to the absence of studies related to matrix components that are involved in triggering diabetes melittus and pancreatitis. The extracellular matrix plays the role of physical support for the cells and allows the regulation of various cellular processes. In this context, it has already been demonstrated that physiologic and pathologic pancreatic changes lead to ECM remodeling, highlighting the importance of an in-depth study of the changes associated with pancreatic diseases.

Origin and Distribution of the Brachial Plexus in Two Procyonids (Procyon cancrivorus and Nasua nasua, Carnivora).

Procyon cancrivorus and Nasua nasua are two procyonids with different evolutionary adaptations to use their thoracic limbs. Therefore, this study aimed to characterize the differences in the brachial plexus between both species. Five P. cancrivorus and five N. nasua cadavers were used to perform this investigation with the permission of the bioethics committee and environmental license. Gross dissections were performed on the cervical, pectoral, and thoracic limb regions to find the origin and distribution of the brachial plexus. The brachial plexus of both species originated in a variant manner from C5-T1, C5-T2, C6-T1, or C6-T2. All brachial plexus nerves were observed and, interestingly, the musculocutaneous sent a communicating branch to the median nerve medially to the axillary artery, forming an ansa axillaris in both species. An ansa pectoralis was also observed medially to the axillary artery. Additionally, in P. cancrivorus, the musculocutaneous nerve innervates the pronator teres and flexor carpi radialis muscles and communicates with the median nerve at the elbow level to continue as a common trunk at the antebrachium. The brachial plexus has differences between both procyonids, although in both species, it could conserve a primitive arrangement present within the infraorder Arctoidea.

Evaluation of the ratio of different major and trace elements in the lens of dogs with cataract.

BACKGROUND: Understanding the elements that support cataract development and searching for available therapeutic methods is essential for scientific and social interest. For that purpose, the role of trace elements has been investigated in this study to better understand the development of cataracts in dogs. OBJECTIVE: The aim of this study was to evaluate the ratio of the major and trace elements by X-ray fluorescence spectrometry in dog cataract lenses to contribute to diagnostic, non-surgical, and ophthalmological preventive data. METHODS: A single lens with a cataract from each of a total of 88 dogs (cataract group) and a healthy lens from each of 6 dogs (control group) were evaluated. The elements calcium (Ca), iron (Fe), copper (Cu), zinc (Zn), magnesium (Mg), manganese (Mn), and potassium (K) were analyzed by energy dispersive X-ray fluorescence and X-ray microfluorescence. RESULTS: The results indicated an increase of Ca, Fe, Cu, and Zn, in association with the reabsorption mechanism of hypermature cataracts. CONCLUSIONS: The ratio of elements Ca, Fe, Cu, and Zn was different in cataract lenses than in healthy lenses, and our results may support the development of therapeutic strategies for cataracts in dogs. The Ca concentrations were distinct in the cataract development stages, and the Fe concentration was relatively higher in males when compared to females. Finally, this research stands out with a particular contribution to the understanding of both cataract formation and prevention.

New virtual platform for teaching comparative animal neuroanatomy based on metameric slices of the central nervous system.

With the limitations imposed by the COVID-19 pandemic, new technologies were used as methods to continue teaching and learning activities. This scenario brought forth the need to develop online tools for teaching. Therefore, this research aimed to develop a digital platform linking the knowledge about the central nervous system (CNS) anatomy from feline, equine, and sheep models. The platform was produced from the analysis of a collection of mesoscopic slides made from the sequenced cross-section of the CNS of a feline, an equine, and a sheep. All sections were analysed and stained using the Paul-Wiegert modified technique. The platform was organized in four modules: (1) Neuroanatomy of the Central Nervous System; (2) Neuroanatomy of Feline; (3) Neuroanatomy of Equine; and (4) Neuroanatomy of sheep. For each module, an explanatory document in PDF was developed, as well as video lectures and a descriptive atlas identifying the structures present in the encephalon and in the cervical part of the spinal cord. Even though there are numerous online platforms that allow the study of veterinary anatomy of different species and organs, the veterinary neuroanatomy platform presented here is the first platform that conjointly addresses the CNS anatomy of felines, equines, and sheep. Future research applying this platform as an aid to the study of neuroanatomy by students, teachers, and veterinary professionals should validate its use as a complementary tool for teaching and learning animal neuroanatomy.

Gross anatomical description of the extrinsic and intrinsic scapular and brachial muscles of Sapajus apella (Linnaeus, 1758).

BACKGROUND: The robust brown capuchin monkey (Sapajus apella) is a South American primate with preferences for arboreal locomotion, which requires specific thoracic limb muscle adaptations. The present investigation studied the gross anatomy of the extrinsic and intrinsic scapular and brachial muscles. METHODS: Gross dissections were performed in both thoracic limbs of four formaldehyde-fixed specimens. RESULTS: Three rhomboideus muscles were present (capitis, cervicis, and thoracis). The trapezius muscle was divided into two parts (cervicis and thoracis). The pectoralis abdominalis and omotransversarius muscles were present. The anconeus muscle was found as an individual muscle or fused to the caput mediale of the triceps brachii muscle. The brachialis muscle had among one and two heads. The anconeus epitrochlearis was absent. CONCLUSION: These muscles of Sapajus apella are adapted for arboreal locomotion and some terrestrial habits, since these have many similarities with other primates with a similar locomotor patterns.

Evolutionary comparative analysis of the extrinsic thoracic limb muscles in three procyonids (Procyon cancrivorus Cuvier, 1798, Nasua nasua Linnaeus, 1766, and Potos flavus Schreber, 1774) based on their attachments and innervation.

The procyonids (Procyon cancrivorus, Nasua nasua and Potos flavus) are Neotropical carnivorans with the ability to climb trees; however, each one has different locomotor preferences. Thereby, P. flavus is highly arboreal, P. cancrivorus is mainly terrestrial with abilities to swim, and N. nasua is also fossorial. These activities not only require movements of the hands but stabilize the thoracic limb, an action performed by the extrinsic muscles. Besides, former descriptions performed in procyonid species have obsolete terms for these muscles, generating confusion about the comparison among species. Thereby, muscle innervation has also been used to support the evolutionary derivation of the muscles. Therefore, this study aimed to describe the attachments and innervations of these muscles in three procyonids. There were intra- and interspecific anatomical variations in the attachments of all extrinsic thoracic limb muscles. However, based on the innervation, several evolutionary derivations in procyonids could be found, such as: the cleidobrachialis muscle derived from the deltoideus muscle; the atlantoscapularis muscle of P. flavus derived from the serratus ventralis cervicis muscle; the pectoralis transversus muscle derived from the pectoralis profundus and superficiales muscles; and the pectoralis abdominalis muscle derived from the cutaneus trunci muscle. Some functions could be associated with locomotor habits, among them a highly developed pectoralis abdominalis in Nasua for its fossorial habits and the atlantoscapularis in Potos for its arboreal and prehensile habits. Thus, the extrinsic muscles in procyonids have evolved for locomotor preferences, but mainly due to their phylogenetic relationship within the family Procyonidae.

Current Trends on Bioengineering Approaches for Ovarian Microenvironment Reconstruction.

Ovarian tissue has a unique microarchitecture and a complex cellular and molecular dynamics that are essential for follicular survival and development. Due to this great complexity, several factors may lead to ovarian insufficiency, and therefore to systemic metabolic disorders and female infertility. Techniques currently used in the reproductive clinic such as oocyte cryopreservation or even ovarian tissue transplant, although effective, have several limitations, which impair their wide application. In this scenario, mimetic ovarian tissue reconstruction comes as an innovative alternative to develop new methodologies for germ cells preservation and ovarian functions restoration. The ovarian extracellular matrix (ECM) is crucial for oocyte viability maintenance, once it acts actively in folliculogenesis. One of the key components of ovarian bioengineering is biomaterials application that mimics ECM and provides conditions for cell anchorage, proliferation, and differentiation. Therefore, this review aims at describing ovarian tissue engineering approaches and listing the main limitations of current methods for preservation and reestablishment of ovarian fertility. In addition, we describe the main elements that structure this study field, highlighting the main advances and the challenges to overcome to develop innovative methodologies to be applied in reproductive medicine. Impact Statement This review presents the main advances in the application of tissue bioengineering in the ovarian tissue reconstruction to develop innovative solutions for ovarian fertility reestablishment.

Scaffolds Vasculares Descelularizados Provenientes de Vasos Sanguíneos de Placenta Bovina / Decellularized Vascular Scaffolds Derived from Bovine Placenta Blood Vessels

Resumo Fundamento As doenças associadas ao aparelho circulatório são as principais causas de morbidade e mortalidade em todo o mundo, implicando a necessidade de implantes vasculares. Assim, a produção de biomateriais vasculares tem se mostrado uma alternativa promissora às terapias utilizadas em estudos e pesquisas relacionados à fisiologia vascular. Objetivos O presente projeto visa ao desenvolvimento artificial de vasos sanguíneos pela recelularização de scaffolds vasculares derivados de vasos placentários bovinos. Métodos A superfície corioalantoide da placenta bovina foi utilizada para produzir biomateriais descelularizados. Para a recelularização, 2,5 x 104 células endoteliais foram semeadas acima de cada fragmento de vaso descelularizado durante três ou sete dias, quando a cultura foi interrompida e os fragmentos foram fixados para análise de adesão celular. Biomateriais descelularizados e recelularizados foram avaliados por histologia básica, microscopia eletrônica de varredura e imuno-histoquímica. Resultados o processo de descelularização produziu vasos que mantiveram a estrutura natural e o conteúdo de elastina, e não foram observadas células e gDNA remanescentes. Além disso, células precursoras endoteliais se ligaram ao lúmen e à superfície externa do vaso descelularizado. Conclusão nossos resultados mostram a possibilidade de usos futuros desse biomaterial na medicina cardiovascular, como, por exemplo, no desenvolvimento de vasos artificiais.

Background Diseases associated with the circulatory system are the main causes of worldwide morbidity and mortality, implying the need for vascular implants. Thus, the production of vascular biomaterials has proven to be a promising alternative to therapies used in studies and research related to vascular physiology. Objectives The present project aims to achieve the artificial development of blood vessels through the recellularization of vascular scaffolds derived from bovine placental vessels. Methods The chorioallantoic surface of the bovine placenta was used to produce decellularized biomaterials. For recellularization, 2.5 x 104 endothelial cells were seeded above each decellularized vessel fragment during three or seven days, when culture were interrupted, and the fragments were fixed for cell attachment analysis. Decellularized and recellularized biomaterials were evaluated by basic histology, scanning electron microscopy, and immunohistochemistry. Results The decellularization process produced vessels that maintained natural structure and elastin content, and no cells or gDNA remains were observed. Endothelial precursor cells were also attached to lumen and external surface of the decellularized vessel.Conclusion: Our results show a possibility of future uses of this biomaterial in cardiovascular medicine, as in the development of engineered vessels.

Mice placental ECM components may provide a three-dimensional placental microenvironment

Bioethical limitations impair deeper studies in human placental physiology, then most studies use human term placentas or murine models. To overcome these challenges, new models have been proposed to mimetize the placental three-dimensional microenvironment. The placental extracellular matrix plays an essential role in several processes, being a part of the establishment of materno-fetal interaction. Regarding these aspects, this study aimed to investigate term mice placental ECM components, highlighting its collagenous and non-collagenous content, and proposing a potential three-dimensional model to mimetize the placental microenvironment. For that, 18.5-day-old mice placenta, both control and decellularized (n = 3 per group) were analyzed on Orbitrap Fusion Lumos spectrometer (ThermoScientific) and LFQ intensity generated on MaxQuant software. Proteomic analysis identified 2317 proteins. Using ECM and cell junction-related ontologies, 118 (5.1%) proteins were filtered. Control and decellularized conditions had no significant differential expression on 76 (64.4%) ECM and cell junction-related proteins. Enriched ontologies in the cellular component domain were related to cell junction, collagen and lipoprotein particles, biological process domain, cell adhesion, vasculature, proteolysis, ECM organization, and molecular function. Enriched pathways were clustered in cell adhesion and invasion, and labyrinthine vasculature regulation. These preserved ECM proteins are responsible for tissue stiffness and could support cell anchoring, modeling a three-dimensional structure that may allow placental microenvironment reconstruction.