Early Osteogenic-Induced Adipose-Derived Stem Cells and Canine Bone Regeneration Potential Analyzed Using Biodegradable Scaffolds.

The complex process of bone regeneration is influenced by factors such as inflammatory responses, tissue interactions, and progenitor cells. Currently, multiple traumas can interfere with fracture healing, causing the prolonging or failure of healing. In these cases, bone grafting is the most effective treatment. However, there are several drawbacks, such as morbidity at the donor site and availability of suitable materials. Advantages have been provided in this field by a variety of stem cell types. Adipose-derived stem cells (ASCs) show promise. In the radiological examination of this study, it was confirmed that the C/S group showed faster regeneration than the other groups, and Micro-CT also showed that the degree of bone formation in the defect area was highest in the C/S group. Compared to the control group, the change in cortical bone area in the defect area decreased in the sham group (0.874), while it slightly increased in the C/S group (1.027). An increase in relative vascularity indicates a decrease in overall bone density, but a weak depression filled with fibrous tissue was observed outside the compact bone. It was confirmed that newly formed cortical bone showed a slight difference in bone density compared to surrounding normal bone tissue due to increased distribution of cortical bone. In this study, we investigated the effect of bone regeneration by ADMSCs measured by radiation and pathological effects. These data can ultimately be applied to humans with important clinical applications in various bone diseases, regenerative, and early stages of formative differentiation.

Case report: Fatal neonatal sepsis associated with Escherichia fergusonii infection in a common bottlenose dolphin (Tursiops truncatus).

A 25-day-old male common bottlenose dolphin (Tursiops truncatus) died suddenly while swimming at a dolphinarium. The gross examination revealed ulceration on the dorsal and pectoral fins and rostrum. Severe congestion, hemorrhage, and edema were observed in the gastrointestinal tract, liver, mesenteric lymph nodes, lungs, and kidneys. Fibrinosuppurative arthritis of the atlantooccipital joint and extension of fibrin into the spinal canal caused compression of the spinal cord. Histopathological examination revealed tracheitis, fibrinosuppurative bronchopneumonia and enteritis. In the central nervous system, meningeal vessel congestion in the brain, and intraparenchymal hemorrhages with neurodegeneration were observed in the spinal cord. Based on the histopathological findings, representative samples, including lung, liver, mesenteric lymph node, blood obtained from the jugular vein, and fluid sample of the ascites, were inoculated on tryptic soy agar and blood agar for routine bacterial isolation. Each isolated bacterial colony was streaked aseptically onto tryptic soy agar and blood agar for pure culture. After then, polymerase chain reaction (PCR) was performed for further identification of pathogenic microorganisms. PCR identified Escherichia fergusonii, Shewanella haliotis, Enterococcus faecalis, and Staphylococcus schleiferi. E. fergusonii was considered the primary etiologic agent in this case since it was the only species identified in all representative samples. The cause of death in this animal was E. fergusonii sepsis. To the best of our knowledge, this is the first case of neonatal sepsis associated with E. fergusonii infection in a dolphin, and suggests E. fergusonii as an opportunistic pathogen associated with sepsis in dolphins.

Histopathological Features of Myxoid Pleomorphic Liposarcoma in an African Pygmy Hedgehog (Atelerix Albiventris).

Myxoid pleomorphic liposarcoma is characterized by pathological features of both pleomorphic liposarcoma and myxoid liposarcoma, as the name suggests. In this case, a myxoid pleomorphic liposarcoma was observed in a 5-year-old male African pygmy hedgehog. It consisted of ~60% of the myxoid substance area with proliferating round cells and ~30% of pleomorphic neoplastic cells. The subject presented with extrapulmonary metastasis, but a good prognosis during 6 months of follow-up, which is similar to the characteristics of myxoid liposarcoma. The histopathological features of myxoid pleomorphic liposarcoma may reflect the features of either myxoid liposarcoma or pleomorphic liposarcoma depending on the proportion of each histopathological feature. The proportion of the pleomorphic area and the myxoid area may offer information on the prognosis and metastasis of myxoid pleomorphic liposarcoma, which will be helpful for setting up a treatment plan. Thus, analyzing the proportion of pleomorphic area and myxoid area could be suggested as one of the ways to predict clinical outcomes. In addition to the fact that this is the first case of a myxoid pleomorphic liposarcoma in hedgehogs, this case is meaningful, considering the unique histopathological characteristics and rare incidence of myxoid pleomorphic liposarcoma that could be important in humans as well.

Long-term treatment of allogeneic adipose-derived stem cells in a dog with rheumatoid arthritis.

BACKGROUND: Although there are growing demands for stem cell-based therapy for companion animals in various diseases, a few clinical trials have been reported. Moreover, most of them are the results from only one or a few times of stem cell injection. OBJECTIVES: The aim of this study is to describe a long-term treatment with allogeneic adipose-derived stem cells (ASCs) in a dog with rheumatoid arthritis (RA), which is a rare canine disease. METHODS: The dog with RA received intravascular injection of allogeneic ASCs derived from two healthy donors once a month for 11 months. To assess therapeutic effects of ASCs, orthopedic examination and clinical evaluation was performed. Cytokines of tumor necrosis factor-α and interleukin-6 in the plasma were measured using ELISA analysis. RESULTS: Despite this repeated and long-term administration of allogeneic ASCs, there were no side effects such as immunorejection responses or cell toxicity. The orthopedic examination score for the dog decreased after ASCs treatment, and the clinical condition of the dog and owner's satisfaction were very good. CONCLUSIONS: Although ASCs has been suggested as one of the options for RA treatment because of its anti-inflammatory and immunosuppressive functions, it has never been used to treat RA in dogs. The present report describes a case of canine RA treated with allogeneic ASCs for long-term in which the dog showed clinical improvement without adverse effects.

Sirt2 positively regulates muscle regeneration after Notexin-induced muscle injury.

Sirt2 regulates various biological processes by deacetylating target genes. Despite roles in regulating proliferation, cell cycle, and glucose metabolism, which are closely associated with skeletal muscle physiology, Sirt2 functions in this tissue remain unclear. In this study, genetic deletion of Sirt2 delayed muscle regeneration after Notexin-induced muscle injury. Gene expressions of myogenic regulatory factors, including Myf5, MyoD, and Myogenin, and cell cycle regulators, such as cyclin D1 and CDK2, were repressed in Sirt2 knockout mice after injury. Also, Sirt2 knockout mice presented muscle atrophy after muscle injury which is associated with the down-regulation of anabolic signaling and the up-regulation of catabolic signaling, in particular, increased atrogin1 transcriptional expression. Thus, Sirt2 positively regulated skeletal muscle regeneration after muscle injury by regulating transcriptional expression involved in myogenesis, cell cycle, and anabolic and catabolic signaling. Based on the in vivo analyses, Sirt2 could function as an interventional therapeutic for chronic myopathy, which is characterized by impaired muscle regeneration and muscle atrophy.

Vitamin C alleviates alcoholic liver injury by suppressing neutrophil infiltration in senescence marker protein 30-knockout mice irrespective of its antioxidant effects.

AIMS: Alcoholic liver disease (ALD) comprises an important component in chronic liver diseases, and its clinical significance has increased due to the high consumption of alcohol worldwide. Vitamin C is a potent antioxidant, and several previous studies have suggested that its therapeutic role in ALD is derived from its antioxidant role. However, its anti-inflammatory role in ALD remains to be elucidated. Especially, the relationship between vitamin C and infiltration of neutrophils in ALD has not been discussed to date. For the reason, the present study investigated the precise role of vitamin C in neutrophil infiltration in ALD. MAIN METHODS: In the present study, wild-type C57BL/6 and vitamin C-deficient senescence marker protein 30-knockout mice were pair-fed with a Lieber-DeCarli control or ethanol diet. Ethanol-fed groups were fed with increasing concentrations of EtOH (Lieber-DeCarli control diet for 5 days, 3% EtOH diet for a week, and 5% diet for 2 weeks) with or without vitamin C supplementation. KEY FINDINGS: Vitamin C dramatically attenuated the ethanol-mediated liver disease in the vitamin C-deficient ethanol-fed mice group by suppressing the infiltration of neutrophils accompanied by less CD68-positive cell infiltration. This attenuating role of vitamin C in neutrophil infiltration in the liver is associated with its protective effect for the ethanol-mediated intestinal damage in vitamin C-deficient ethanol-fed mice. SIGNIFICANCE: This study provides a novel possibility of vitamin C to be used as an anti-inflammatory therapeutic agent associated with neutrophil infiltration in ALD, thereby helping to establish strategies for attenuating ALD.

The role of Sirtuin 2 in sustaining functional integrity of the liver.

AIM: Sirtuin 2 (SIRT2) is a NAD+-dependent deacetylase involved in various biological functions via deacetylation of proteins, including histone protein. Hepatic fat accumulation from aging and excess caloric intake contribute to development of non-alcoholic fatty liver disease. The study aim was to elucidate the role of SIRT2 in lipid metabolism homeostasis. MATERIALS AND METHODS: SIRT2+/+ (C57BL/6) and SIRT2-/- were randomly assigned to normal diet or high-fat diet (HFD) groups and fed for 6 weeks. Histological features of the livers were evaluated by hematoxylin and eosin and Masson's trichrome staining, and the levels of selected factors were determined by quantitative reverse transcription-polymerase chain reaction and western blot analysis. KEY FINDINGS: Although the SIRT2-/- mice were viable, their livers exhibited higher glycogen accumulation, and skeletal muscle showed features of increased metabolic demand. The SIRT2-/- mice attenuated HFD-induced weight gain, visceral adipose tissue formation, and fat accumulation in the liver in which the expressions of genes involved in metabolic substrate transport were modified. Additionally, the hepatocellular senescence and upregulated cell-cycle factors upon HFD intake in SIRT2-/- livers suggested a role of SIRT2 in gene expression during abnormal metabolism. Moreover, the fibrotic phenotype of liver tissue without fat accumulation and the increased expression of genes involved in liver fibrosis in the HFD-fed SIRT2-/- mice indicated that SIRT2 had a role in hepatocyte and hepatic stellate cell activation. SIGNIFICANCE: Our results indicated that SIRT2 has a critical role in regulating lipid metabolic homeostasis and in sustaining liver integrity by modulating related gene expression.

Vitamin C Deficiency Inhibits Nonalcoholic Fatty Liver Disease Progression through Impaired de Novo Lipogenesis.

Despite the increasing clinical importance of nonalcoholic fatty liver disease (NAFLD), little is known about its underlying pathogenesis or specific treatment. The senescence marker protein 30 (SMP30), which regulates the biosynthesis of vitamin C (VC) in many mammals, except primates and humans, was recently recognized as a gluconolactonase. However, the precise relation between VC and lipid metabolism in NAFLD is not completely understood. Therefore, this study aimed to clearly reveal the role of VC in NAFLD progression. SMP30 knockout (KO) mice were used as a VC-deficient mouse model. To investigate the precise role of VC on lipid metabolism, 13- to 15-week-old SMP30 KO mice and wild-type mice fed a 60% high-fat diet were exposed to tap water or VC-containing water (1.5 g/L) ad libitum for 11 weeks. Primary mouse hepatocytes isolated from the SMP30 KO and wild-type mice were used to demonstrate the relation between VC and lipid metabolism in hepatocytes. Long-term VC deficiency significantly suppressed the progression of simple steatosis. The high-fat diet-fed VC-deficient SMP30 KO mice exhibited impaired sterol regulatory element-binding protein-1c activation because of excessive cholesterol accumulation in hepatocytes. Long-term VC deficiency inhibits de novo lipogenesis through impaired sterol regulatory element-binding protein-1c activation.

Effects of losartan and l-serine in a mouse liver fibrosis model.

Hepatic fibrosis is a common liver disease caused by excessive collagen deposition in the liver. Since liver transplantation is the only current treatment for cirrhosis with worsened fibrosis, a new strategy to develop anti-fibrosis drugs with no adverse effects is necessary. In recent studies, amino acids have been applied as a type of therapy in various fields. l-serine plays a major role in antioxidant production via the maintenance of nicotinamide adenine dinucleotide phosphate hydride production in the mitochondria. l-serine may reduce fibrotic lesions in a mouse model of chronic liver injury. This study used 27 six-week-old C57BL/6 mice and injected them three times a week for eight weeks with carbon tetrachloride (CCl4) (1.5 mg/kg, 10% v/v CCl4 in olive oil) to create a hepatic fibrosis mouse model. The mice, which weighed approximately 20-30 g, were randomly classified into four groups: 1) the olive oil group, which received intraperitoneal injection of olive oil (1.5 mg/kg, 3 times per week for 8 weeks); 2) the CCl4-only group; 3) the CCl4 + losartan (10 mg/kg, PO, 5 days on, weekend off for 8 weeks) group; and 4) the CCl4 + l-serine (100 g/L, free access for 8 weeks) group. Hematoxylin and eosin staining and Masson's trichrome staining showed reduced inflammatory cell deposition and collagen deposition in the liver tissue in the l-serine supplemented group. l-serine was found to reduce the spread of hepatic fibrosis and has potential use in clinical settings. Based on these histopathological observations, l-serine is a potential anti-fibrosis drug.

Nuclear VEGFR-2 Expression of Hepatocytes Is Involved in Hepatocyte Proliferation and Liver Regeneration During Chronic Liver Injury.

BACKGROUND/AIM: The pathological role of vascular endothelial growth factor receptor 2 (VEGFR-2) in chronic liver injury and liver regeneration is not fully understood. This study analysed the role of VEGFR-2 in liver fibrosis and its regeneration process. MATERIALS AND METHODS: We administered intraperitoneally 50 mg/kg to 300 mg/kg thioacetamide (TAA) to 9-week-old male mice for 17 weeks. We measured levels of VEGFR-2 protein and identified the location of cells that specifically express VEGFR-2. RESULTS: VEGFR-2 is rarely expressed in normal hepatocytes. However, high VEGFR-2 expression in liver sinusoidal endothelial cells was noted in the TAA group. Conversely, the group that experienced regeneration from liver fibrosis showed significantly higher VEGFR-2 expression in the nucleus of hepatocytes compared to the other groups. CONCLUSION: VEGFR-2 plays a pivotal role in the nucleus of hepatocytes during liver regeneration and VEGFR-2 may be closely related to cell division. Therefore, VEGFR-2 may be a new therapeutic target for liver regeneration.