Role of Metalloproteinases in Diabetes-associated Mild Cognitive Impairment.

Diabetes has been linked to an increased risk of mild cognitive impairment (MCI), a condition characterized by a subtle cognitive decline that may precede the development of dementia. The underlying mechanisms connecting diabetes and MCI involve complex interactions between metabolic dysregulation, inflammation, and neurodegeneration. A critical mechanism implicated in diabetes and MCI is the activation of inflammatory pathways. Chronic low-grade inflammation, as observed in diabetes, can lead to the production of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1 beta (IL-1ß), and interferon-gamma (IFNγ), each of which can exacerbate neuroinflammation and contribute to cognitive decline. A crucial enzyme involved in regulating inflammation is ADAM17, a disintegrin, and metalloproteinase, which can cleave and release TNF-α from its membrane-bound precursor and cause it to become activated. These processes, in turn, activate additional inflammation-related pathways, such as AKT, NF-κB, NLP3, MAPK, and JAK-STAT pathways. Recent research has provided novel insights into the role of ADAM17 in diabetes and neurodegenerative diseases. ADAM17 is upregulated in both diabetes and Alzheimer's disease, suggesting a shared mechanism and implicating inflammation as a possible contributor to much broader forms of pathology and pointing to a possible link between inflammation and the emergence of MCI. This review provides an overview of the different roles of ADAM17 in diabetes-associated mild cognitive impairment diseases. It identifies mechanistic connections through which ADAM17 and associated pathways may influence the emergence of mild cognitive impairment.

3D culture of mesenchymal stem cells from the yolk sac to generate intestinal organoid.

Organoids are in vitro models that originated from the three-dimensional culture of stem cells with the ability to reproduce part of the in vivo structural and functional specificities of body organs. Intestinal organoids have great relevance in cell therapy, as they provide more accurate information about tissue composition and architecture in relation to two-dimensional culture, in addition to serving as a study model for host interaction and drug testing. The yolk sac (YS) is a promising source of mesenchymal stem cells (MSCs), which are multipotent stem cells with self-renewal ability and potential to differentiated into mesenchymal lineages. Besides this, the YS is responsible for the formation of intestinal epithelium during embryonic development. Thus, the aim of this study was to verify if the three-dimensional in vitro culture of stem cells derived from the canine YS is capable of developing intestinal organoids. MSCs from the canine YS and gut cells were isolated and characterized, then three-dimensionally cultured in Matrigel. In both cells lineages, spherical organoids were observed and after 10 days the gut cells formed crypt-like buds and villus-like structures. Despite having the same induction of differentiation process and having the expression of intestinal markers, the MSC from the YS morphology was not in the form of crypt budding. The hypothesis is that these cells could generate structures equivalent to the intestinal organoids of the colon that other studies showed formed only spherical structures. The culture of MSC from the YS, as well as the establishment of protocols for 3D cultivation of this tissue, is relevant, as it will serve as a tool in various applications in basic and scientific biology.

Initial Characterization of 3D Culture of Yolk Sac Tissue.

The role of the yolk sac (YS) in miscarriage is not yet clear, largely due to ethical reasons that make in vivo studies difficult to conduct. However, 3D cultures could provide a solution to this problem by enabling cells to be arranged in a way that more closely mimics the structure of the YS as it exists in vivo. In this study, three domestic species (porcine, canine, and bovine) were chosen as models to standardize 3D culture techniques for the YS. Two techniques of 3D culture were chosen: the Matrigel® and Hanging-Drop techniques, and the 2D culture technique was used as a standardized method. The formed structures were initially characterized using scanning electron microscopy (SEM), immunohistochemistry (IHC), and quantitative real-time PCR (RT-qPCR). In general, the 3D culture samples showed better organization of the YS cells compared to 2D cultures. The formed structures from both 3D methods assemble the mesothelial layer of YS tissue. Regarding the IHC assay, all in vitro models were able to express zinc and cholesterol transport markers, although only 3D culture techniques were able to generate structures with different markers pattern, indicating a cell differentiation process when compared to 2D cultures. Regarding mRNA expression, the 3D models had a greater gene expression pattern on the Hemoglobin subunit zeta-like (HBZ) gene related to the YS tissue, although no significant expression was found in Alpha-fetoprotein (AFP), indicating a lack of endodermal differentiation in our 3D model. With the initial technique and characterization established, the next step is to maintain the cultures and characterize the diversity of cell populations, stemness, functions, and genetic stability of each 3D in vitro model.

Ozone therapy: protocol for treating canine parvovirus infection.

Canine Parvovirus infection is a disease caused by Canine Parvovirus (CPV) that results in hemorrhagic gastroenteritis and secondary infections, mainly in puppies between six weeks and six months old that are not immunized. Since there is no specific treatment for the condition, supportive therapy based on antibiotics, antiemetics, and non-steroidal anti-inflammatory drugs is traditionally used. Ozone therapy is an economical treatment that has bactericidal, fungicidal, and antiviral properties, besides promoting oxygenation and tissue regeneration, as well as anti-inflammatory and analgesic effects, and was used as a complementary therapy in this study. Therefore, four mixed-breed dogs, aged between 2 and 3 months, with no previous immunization against CPV and testing positive for the virus in a rapid test were selected. The animals were randomly distributed into two groups, being 1: the control group (n=2) that received only supportive treatment; and 2: the experimental group (n=2), that in addition to conventional therapy received intravenously 500 mL of ozonized Ringer's Lactate solution. Before treatment and after 24 and 48 hours, the following clinical signs were evaluated: episodes of emesis and diarrhea, weight, hydration, blood glucose level, abdominal pain, and blood count. One control group animal died within the first hours of hospitalization. Both animals in the experimental group presented faster resolution of diarrheal episodes and shorter hospitalization time when compared to the surviving animal that received only supportive treatment. Although further studies are needed, ozone therapy showed promising results for the treatment of canine parvovirus.

A Parvovirose canina é uma doença infecciosa causada pelo Parvovírus Canino (CPV) que resulta em gastroenterite hemorrágica e infecções secundárias, principalmente em cachorros entre seis semanas e seis meses de idade não imunizados. Como não existe tratamento específico para a doença, utiliza-se tradicionalmente terapia de suporte baseada em antibióticos, antieméticos, e anti-inflamatórios não esteroides. A Ozonioterapia é um tratamento econômico com propriedades bactericidas, fungicidas e antivirais, além de promover a oxigenação e a regeneração dos tecidos, efeitos anti-inflamatórios e analgésicos, e foi utilizada como terapia complementar neste estudo. Neste estudo, foram selecionados quatro cães sem raça definida, com idades entre 2 e 3 meses, sem imunização prévia contra CPV, que testaram positivo para o vírus em um teste rápido. Os animais foram distribuídos aleatoriamente em dois grupos, sendo 1: o grupo controle (n=2) que recebeu apenas tratamento de suporte; e 2: o grupo experimental (n=2), que além da terapia convencional recebeu por via intravenosa 500 mL de Lactato de Ringer ozonizado. Antes do tratamento, após 24 e 48 horas, foram avaliados os seguintes sinais clínicos: episódios de êmese e diarreia, peso, hidratação, glicemia, dores abdominais, e hemograma. Um animal do grupo controle foi a óbito nas primeiras horas de internação. Ambos os animais do grupo experimental apresentaram uma resolução mais rápida dos episódios de diarreia e um tempo de internação mais curto quando comparado com o animal sobrevivente que recebeu apenas tratamento de suporte. Embora sejam necessários mais estudos, a ozonoterapia demonstrou resultados promissores para o tratamento do parvovírus canino.

Addition of synthetic polymer in the freezing solution of mesenchymal stem cells from equine adipose tissue as a future perspective for reducing of DMSO concentration.

The regenerative therapies with stem cells (SC) has been increased by the cryopreservation, permitting cell storage for extended periods. However, the permeating cryoprotectant agents (CPAs) such as dimethylsulfoxide (DMSO) can cause severe adverse effects. Therefore, this study evaluated equine mesenchymal stem cells derived from adipose tissue (eAT-MSCs) in fresh (Control) or after slow freezing (SF) in different freezing solutions (FS). The FS comprise DMSO and non-permeating CPAs [Trehalose (T) and the SuperCool X-1000 (X)] in association or not, totalizing seven different FS: (DMSO; T; X; DMSO+T; DMSO+X; T+X, and DMSO+T+X). Before and after cryopreservation were evaluated, viability, colony forming unit (CFU), and cellular differentiation capacity. After freezing-thawing, the viability of the eAT-MSCs reduced (P< 0.05) in all treatments compared to the control. However, the viability of frozen eAT-MSCs in DMSO (80.3 ± 0.6) was superior (P<0.05) to the other FS. Regarding CFU, no difference (P>0.05) was observed between fresh and frozen cells. After freezing-thawing, the eAT-MSCs showed osteogenic, chondrogenic, and adipogenic lineages differentiation potential. Nonetheless, despite the significative reduction in the osteogenic differentiation capacity between fresh and frozen cells, no differences (P > 0.05) were observed among FS. Furthermore, the number of chondrogenic differentiation cells frozen in DMSO+X solution reduced (P<0.05) comparing to the control, without differ (P>0.05) to the other FS. The adipogenic differentiation did not differ (P>0.05) among treatments. In conclusion, although these findings confirm the success of DMSO to cryopreserve eAT-MSCs, the Super Cool X-1000 could be a promise to reduce the DMSO concentration in a FS.

As terapias regenerativas com células-tronco (CT) têm sido incrementadas pela criopreservação, permitindo o armazenamento celular. No entanto, os agentes crioprotetores (ACPs) penetrantes, como DMSO, podem causar efeitos adversos graves. Portanto, este estudo avaliou células-tronco mesenquimais equinas derivadas de tecido adiposo (CTM-TAe) in natura (Controle) ou após congelamento lento (CL) em diferentes soluções de congelamento (SC). As SCs compreendem DMSO e ACPs não permeáveis [Trealose (T) e o SuperCool X-1000 (X)] associados ou não: (DMSO; T; X; DMSO+T; DMSO+X; T +X e DMSO+T+X). Antes e após a criopreservação foram avaliados, viabilidade, unidade formadora de colônia (UFC) e capacidade de diferenciação celular. Após o congelamento-descongelamento, a viabilidade das CTM-TAe reduziu (P< 0,05) em todos os tratamentos em relação ao controle. Entretanto, a viabilidade das CTM-TAe congeladas em DMSO (80,3 ± 0,6) foi superior (P<0,05) às demais SC. Em relação às UFC, não houve diferença (P>0,05) entre células frescas e congeladas. Após congelamento-descongelamento, as CTM-TAe apresentaram potencial de diferenciação de linhagens osteogênicas, condrogênicas e adipogênicas. No entanto, apesar da redução significativa na capacidade de diferenciação osteogênica entre células frescas e congeladas, não foram observadas diferenças (P > 0,05) entre SCs. Além disso, o número de células de diferenciação condrogênica congeladas em solução de DMSO+X reduziu (P<0,05) em relação ao controle, sem diferir (P>0,05) das demais SCs. A diferenciação adipogênica não diferiu (P>0,05) entre os tratamentos. Em conclusão, embora esses achados confirmem o sucesso do DMSO para criopreservar CTM-TAe, o Super Cool X-1000 pode ser uma promessa para reduzir a concentração de DMSO.

Potential application of aminiotic stem cells in veterinary medicine.

In regenerative medicine stem cell biology has become one of the most interesting and more often studied subject. The amniotic membrane is the innermost layer of the fetal membranes and is considered a potential tool to treat many pathologies. It is used because it can be collected from discarded fetal material and is a rich source of stem cells with high proliferation and plasticity ratio capable of proliferating and differentiate in vitro. We propose to elucidate the characteristics and potencial clinical application of cells derived of amniotic membrane in veterinary medicine.

Neurons-derived extracellular vesicles promote neural differentiation of ADSCs: a model to prevent peripheral nerve degeneration.

Potential mechanisms involved in neural differentiation of adipocyte derived stem cells (ADSCs) are still unclear. In the present study, extracellular vesicles (EVs) were tested as a potential mechanism involved in the neuronal differentiation of stem cells. In order to address this, ADSCs and neurons (BRC) were established in primary culture and co-culture at three timepoints. Furthermore, we evaluated protein and transcript levels of differentiated ADSCs from the same timepoints, to confirm phenotype change to neuronal linage. Importantly, neuron-derived EVs cargo and EVs originated from co-culture were analyzed and tested in terms of function, such as gene expression and microRNA levels related to the adult neurogenesis process. Ideal neuron-like cells were identified and, therefore, we speculated the in vivo function of these cells in acute sciatic nerve injury. Overall, our data demonstrated that ADSCs in indirect contact with neurons differentiated into neuron-like cells. Neuron-derived EVs appear to play an important role in this process carrying SNAP25, miR-132 and miR-9. Additionally, in vivo neuron-like cells helped in microenvironment modulation probably preventing peripheral nerve injury degeneration. Consequently, our findings provide new insight of future methods of ADSC induction into neuronal linage to be applied in peripheral nerve (PN) injury.