L-Proline as a Cryoprotective Agent for the Preservation of Galea Spixii Skin Fibroblasts.

Somatic cell biobanking is a promising strategy for developing reproductive techniques. Although cryopreservation, a technique used for creating biobanks, has been performed on Galea spixii, structural and physiological damage to its cells highlight the need to optimize the cryoprotective solution being used. Therefore, the osmoprotective activity of 5 mM L-proline was evaluated as an alternative cryoprotectant for G. spixii fibroblast conservation. The concentration was defined based on previous studies conducted on mammalian cells. Cells derived from the skin of six individuals were cultured until the fifth passage were cryopreserved under the following treatments: (i) control (non-cryopreserved); (ii) a solution with 10% dimethyl sulfoxide (Me2SO), 10% fetal bovine serum (FBS), and 0.2 M sucrose; (iii) a solution with 10% Me2SO, 10% FBS, and 5 mM L-proline; and (iv) a solution with 10% Me2SO, 10% FBS, 0.2 M sucrose, and 5 mM L-proline. Tests were conducted to analyze cell morphology, viability, metabolism, proliferation, and apoptosis; reactive oxygen species (ROS) levels; and mitochondrial membrane activity (ΔΨm). A reduction in the number of viable cells (72.3% ± 1.2%) was observed in the sucrose-containing group compared to the control (86.7% ± 2.0%) and L-proline (88.4% ± 1.8% and 87.8% ± 2.1%) groups. After apoptotic analysis, a reduction in the number of viable cells was observed in the group with sucrose alone (74.6% ± 4.1%) compared to the control group (88.2% ± 1.1%). The ROS levels (1.03 ± 0.5 and 1.07 ± 0.5, respectively) and ΔΨm values (0.99 ± 0.42 and 1.22 ± 0.73, respectively) observed in the groups with L-proline were similar to that observed in the control group (1.00 ± 0.5 and 1.00 ± 0.4, respectively). Moreover, no difference was observed between groups for cell morphology, metabolism, or proliferation. Thus, L-proline is a cryoprotectant agent that can be used during G. spixii fibroblast cryopreservation, alone or with sucrose. In addition, we developed an adequate biobank for G. spixii, whereby stored cells could be used for reproductive techniques.

Age and sex effects on histological features and in vitro culturing of Antillean manatee (Trichechus manatus manatus, Linnaeus 1758) dermis.

The biobanks from dermal biopsies represent an interesting strategy for biodiversity conservation. Nevertheless, the morphological and cellular patterns of the dermis can be influenced by the age and sex of the individual. Therefore, evaluating these factors is interesting for forming biobanks of Antillean manatees. These animals, representatives of marine fauna, have had their population reduced, and biobanks are essential for their conservation. Then, we evaluated the effects of age (3.5 years vs. 3.6-16 years vs. 23.6 years) and sex (males vs. females) on morphological and cellular parameters using histological and in vitro culture techniques. Regardless of age, no differences were observed for dermal thickness, collagen fibres, tissue proliferative activity and viable cell recovery. Nonetheless, fibroblast reduction was observed in groups aged 23.6 years compared to other animals (p < 0.05). Additionally, cells from animals aged 3.6-16 years showed more significant mitochondrial damage than the other groups (p < 0.05). Regardless of sex, no differences were observed for dermal thickness, collagen fibres, tissue proliferative activity and viable cell recovery; however, females had fewer fibroblasts than males (p < 0.05). Cells from females showed lower mitochondrial damage when compared to cells from males. In summary, although age and sex do not influence dermal thickness and cell recovery, variations in the number of fibroblasts and mitochondrial characteristics were observed among the groups. These differences may be significant for understanding the dermis aspects to be correlated to biobank systems.

Different Methods for Seminal Plasma Removal and Sperm Selection on the Quality and Fertility of Collared Peccary Sperm.

Methods for seminal plasma (SP) removal and the selection of collared peccary sperm for fertilization were compared. The experiments evaluated the following: the (I) impact of centrifugation for SP removal before swim-up for sperm selection and (II) a comparison of different Percoll® gradient densities (PG 45-90% and PG 35-70%). Non-selected sperm served as the control. Sperm quality was assessed based on motility patterns, morphology, membrane functional integrity, viability, reactive oxygen species (ROS), glutathione (GSH), and DNA integrity. Subsequently, the most successful group in the previous experiment and washing by centrifugation (WC) were compared for motility patterns and fertilization using pig oocytes. Swim-up decreased motility and enhanced ROS compared to the control. Centrifugation before swim-up harmed integrity and viability compared to the control. PG 45-90% (96.8 vs. 69.7 vs. 40.7 µm/s) allowed for a better velocity average pathway (VAP), a better velocity straight line, and better linearity (LIN) than those of the control and PG 35-70% (88.4 vs. 56.0 vs. 27.3 µm/s). Thus, PG 45-90% was used for fertilization. PG 45-90% obtained a higher VAP, a higher amplitude of the lateral head, straightness, and higher LIN than those of the control and WC. Cleavage (25.2-26.3%) and morula (8.1-10.5%) rates did not differ between the groups. Therefore, PG 45-90% and WC were efficient in isolating collared peccary sperm capable of fertilizing pig oocytes.

Morphological, Ultrastructural, and Immunocytochemical Characterization and Assessment of Puma (Puma concolor Linnaeus, 1771) Cell Lines After Extended Culture and Cryopreservation.

Cell lines are valuable tools to safeguard genetic material from species threatened with extinction that is mainly due to human action. In this scenario, the puma constitutes a species whose population is being rapidly reduced in the ecosystems it inhabits. For the first time, we characterized puma skin-derived cell lines and assessed these cells after extended culture (experiment 1) and cryopreservation (experiment 2). Initially, we identified and characterized four dermal fibroblast lines using morphology, ultrastructure, and immunofluorescence assays. Moreover, we evaluated the effects of culture time (1st, 3rd, and 10th passages) and cryopreservation on their morphology, ultrastructure, viability, metabolism, proliferative activity, reactive oxygen species (ROS) levels, mitochondrial membrane potential (ΔΨm), and apoptosis. The cells showed a typical spindle-shaped morphology with centrally located oval nuclei. The cells were identified as fibroblasts by staining for vimentin. In vitro culture after the 1st, 3rd, and 10th passages did not alter most of the evaluated parameters. Cells in the 3rd and 10th passages showed a reduction in ROS levels (p < 0.05). The ultrastructure revealed morphological damage in the prolongments, and nuclei of cells derived from the 3rd and 10th passages. Moreover, cryopreservation resulted in a reduction in ΔΨm compared with that of noncryopreserved cells, suggesting that the optimization of cryopreservation methods for puma fibroblasts is essential. In conclusion, we found that viable fibroblasts could be obtained from puma skin, with slight changes after the 10th passage in in vitro culture and cryopreservation. This is the first report on the development of cell lines derived from pumas.

Evaluation of different skin regions derived from a postmortem jaguar, Panthera onca (Linnaeus, 1758), after vitrification for development of cryobanks from captive animals.

Biological resource banks represent valuable tools for the conservation of species vulnerable to extinction, such as the jaguar. Cryobanks of skins have the potential to safeguard rare genotypes, allowing the potential exploitation of biological samples in animal multiplication technologies and the study of genetic variability. Determination of the most suitable skin regions for tissue conservation can help increase the efficiency of cryobanks and the storage of biological samples. To this end, we evaluated the effects of vitrification of skin tissues from the ear, caudal, and femoral regions of a post-mortem jaguar belonging to a zoo in Brazil. Non-vitrified and vitrified samples were evaluated and compared using quantitative methods, focusing on skin thickness, cell quantification, number of perinuclear halos, collagen and elastic density, and proliferative activity. No differences were observed in skin thickness, number of perinuclear halos, elastic density, and proliferative activity between non-vitrified and vitrified tissues in skin from any region. However, vitrified tissues derived from femoral skin showed a reduction in the number of fibroblasts, epidermal cells and collagen density compared to non-vitrified tissues. In summary, the ear and caudal regions provided the best conservation of somatic tissues derived from jaguars, and skin samples from these regions are therefore the most suitable for the formation of cryobanks.

Ultrastructural and morphometric description of the ear skin and cartilage of two South American wild histricognate rodents (Dasyprocta leporina and Galea spixii) / Descrição ultraestrutural e morfométrica da pele e cartilagem auricular de dois roedores histricognatos silvestres da América do Sul (Dasyprocta leporina e Galea spixii)

Skin and cartilage have been the main source for the recovery of somatic cells to be used in conservation strategies in wild mammals. In this sense, an important step for the cryopreservation of these samples is to recognize the properties of the skin and cartilage. Thus, knowing that the skin may differ among species and aiming to contribute to the establishment of cryobanks, the study examined the differences in the ear skin and cartilage of wild rodents from South America, agouti (Dasyprocta leporina) and spix's yellow-toothed cavy (Galea spixii). Ultrastructural and quantitative methods were used to measure skin and cartilage thickness, density of collagen and elastic fibers, cell type number and distribution, and proliferative activity. Although ultrastructural analysis revealed a similar pattern between species, morphometric analysis of the skin and cartilage showed differences between agoutis and cavies regarding thickness of epidermis layers (corneum: 5.3±2.5μm vs. 3.9±0.6μm; intermediate: 16.4±6.2μm vs. 23.4±8.1μm; basal: 9.9±2.1μm vs. 4.8±0.5μm), dermis (183.1±44.0μm vs. 258.2±22.9μm), total skin (211.8±46.0μm vs. 290.3±23.7μm) and perichondrium (27.6±6.1μm vs. 10.5±1.8μm). A greater number of epidermal cells (61.7±15.2 vs. 24.8±7.6) and chondrocytes (32.7±9.0 vs. 27.5±4.7) were observed in agouti, while the cavy presented a greater number of melanocytes (12.6±4.7 vs. 29.9±6.2), keratinocytes (14.7±4.2 vs. 29.8±7.6), and fibroblasts (103.6±24.7 vs. 112.2±11.3). Moreover, a higher percentage of collagen fibers and proliferative activity was observed in the skin of cavies, when compared to the skin of agoutis. Therefore, there are differences between agouti and cavy for ear skin and cartilage, requiring the establishment of species-specific cryopreservation protocols.(AU)

A pele e cartilagem têm sido uma importante fonte de recuperação de células somáticas a serem utilizadas em estratégias de conservação em mamíferos silvestres. Nesse contexto, uma importante etapa para criopreservação é conhecer, inicialmente, as propriedades que compõem a pele e cartilagem. Sabendo, então, que a pele pode diferir-se entre espécies e com o objetivo de contribuir para o estabelecimento de criobancos, o estudo evidenciou as diferenças da pele e da cartilagem do pavilhão auricular apical de cutias (Dasyprocta leporina) e preás (Galea spixii) que são roedores silvestres presentes na América do Sul. Para tanto, métodos ultraestruturais e quantitativos foram utilizados para mensurar a espessura da pele e da cartilagem, densidade de fibras colágenas e elásticas, número e distribuição dos tipos celulares e atividade proliferativa. Embora as propriedades ultraestruturais em cutias e preás tenham se mostrado semelhantes, avaliações acerca da morfometria da pele e da cartilagem demonstrou diferenças, especialmente nas camadas epidérmicas (córnea: 5,3±2,5μm vs. 3,9±0,6μm; espinhosa: 16,4±6,2μm vs. 23,4±8,1μm; basal: 9,9±2,1μm vs. 4,8±0,5μm), derme (183,1±44,0μm vs. 258,2±22,9μm), pele total (211,8±46,0μm vs. 290,3±23,7μm) e pericôndrio (27,6±6,1μm vs. 10,5±1,8μm). Além disso, um número maior de células epidérmicas (61,7±15,2 vs. 24,8±7,6) e condrócitos (32,7±9,0 vs. 27,5±4,7) foram observados em cutias, enquanto em preás um maior número de melanócitos (12,6±4,7 vs. 29,9±6,2), queratinócitos (14,7±4,2 vs. 29,8±7,6) e fibroblastos (103,6±24,7 vs. 112,2±11,3) foram evidenciados. Ainda, em preás, uma maior porcentagem de fibras colágenas e da atividade proliferativa foram observadas quando comparadas a pele de cutias. Portanto, existem diferenças entre cutias e preás para pele e cartilagem do pavilhão auricular, exigindo desta forma um estabelecimento de protocolos de criopreservação específica para cada uma destas espécies.(AU)

Effects of Vitrification Techniques on the Somatic Tissue Preservation of Agouti (Dasyprocta leporina Linnaeus, 1758).

The cryobanks of agouti somatic tissues represent a promising tool for the conservation of this species and of those that are phylogenetically related and endangered. For these purposes, one strategy to guarantee the quality of samples after warming would be to choose the appropriate tissue vitrification technique. Therefore, we evaluated the effects of two different techniques, direct vitrification in cryovials (DVC) and solid-surface vitrification (SSV), on the preservation of ear somatic tissues derived from agoutis kept in a scientific center of creation. Noncryopreserved somatic tissues were used as controls. Although SSV reduced the thickness of the dermis and cartilage (p < 0.05), the epidermal thickness of these samples was observed to be similar to controls (p > 0.05). Notably, the number of fibroblasts was not altered with either technique. However, both vitrification methods led to an increase in the number of perinuclear halos, with a particularly strong increase observed in DVC-derived fragments (p < 0.05). Compared with the DVC group, SSV showed a larger number of normal chondrocytes and smaller number of degenerate chondrocytes. Furthermore, the number of empty lacunae in SSV-derived fragments remained similar to controls (p > 0.05). In summary, SSV was found to be a more efficient method for vitrifying agouti somatic tissues compared with DVC. These results are important for the proper formation of agouti somatic banks, an essential step in the study of biological resources in this species.