Toshie Iseri

Aldehyde dehydrogenase activity helps identify a subpopulation of murine adipose-derived stem cells with enhanced adipogenic and osteogenic differentiation potential

AIM To identify and characterize functionally distinct subpopulation of adipose-derived stem cells (ADSCs). METHODS ADSCs cultured from mouse subcutaneous adipose tissue were sorted fluorescence-activated cell sorter based on aldehyde dehydrogenase (ALDH) activity, a widely used stem cell marker. Differentiation potentials were analyzed by utilizing immunocytofluorescece and its quantitative analysis. RESULTS Approximately 15% of bulk ADSCs showed high ALDH activity in flow cytometric analysis. Although significant difference was not seen in proliferation capacity, the adipogenic and osteogenic differentiation capacity was higher in ALDHHi subpopulations than in ALDHLo. Gene set enrichment analysis revealed that ribosome-related gene sets were enriched in the ALDHHi subpopulation. CONCLUSION High ALDH activity is a useful marker for identifying functionally different subpopulations in murine ADSCs. Additionally, we suggested the importance of ribosome for differentiation of ADSCs by gene set enrichment analysis.

Comparison of postoperative pain and inflammation reaction in dogs undergoing preventive laparoscopic-assisted and incisional gastropexy

This study compared the effects of postoperative pain and inflammation reaction after preventive laparoscopic-assisted gastropexy (LAG) and incisional gastropexy (IG) in 10 clinically normal Beagles. Surgical time, incision length, visual analog scale (VAS) score, University of Melbourne Pain Scale (UMPS) score, and plasma C-reactive protein (CRP), plasma cortisol (COR), and serum interleukin-6 (IL-6) levels were evaluated. The VAS and UMPS scores and COR and IL-6 levels were recorded at 0.5, 1, 2, 4, 8, 12, 18 and 24 hr after surgery. CRP level was recorded at 12, 24 and 48 hr after surgery. The VAS and UMPS scores showed no significant intergroup differences. Compared to IG, LAG had significantly lower surgical time (45 ± 9.91 min vs 64 ± 5.30 min; P<0.05), incision length (46 ± 8.21 mm vs 129 ± 19.49 mm; P<0.05), CRP level (12 hr after surgery; 4.58 ± 1.58 mg/dl vs 12.4 ± 1.34 mg/dl; P<0.01), and COR level (1 hr after surgery; 10.79 ± 3.07 µg/dl vs 15.9 ± 3.77 µg/dl; P<0.05). IL-6 levels showed no significant intergroup differences at any time point. However, LAG resulted in lower IL-6 levels than did IG at all postoperative time points. Neither procedure resulted in significant surgical complications. LAG produced lower surgical stress than did IG, suggesting that LAG is a safe, minimally invasive, and highly useful technique for preventing canine gastric dilatation-volvulus. Nevertheless, since this study used experimental models, its usefulness should be evaluated in future cases.

Aldehyde dehydrogenase activity identifies a subpopulation of canine adipose-derived stem cells with higher differentiation potential

Adipose-derived stem cells (ADSCs) are abundant and readily obtained, and have been studied for their clinical applicability in regenerative medicine. Some surface antigens have been identified as markers of different ADSC subpopulations in mice and humans. However, it is unclear whether functionally distinct subpopulations exist in dogs. To address this issue, we evaluated aldehyde dehydrogenase (ALDH) activity—a widely used stem cell marker in mice and humans—by flow cytometry. Approximately 20% of bulk ADSCs showed high ALDH activity. Compared to cells with low activity (ALDHLo), the high-activity (ALDHHi) subpopulation exhibited a higher capacity for adipogenic and osteogenic differentiation. This is the first report of distinct ADSC subpopulations in dogs that differ in terms of adipogenic and osteogenic differentiation potential.

Craniocervical junction abnormalities with atlantoaxial subluxation caused by ventral subluxation of C2 in a dog

Craniocervical junction abnormalities with atlantoaxial subluxation caused by ventral subluxation of C2 were diagnosed in a 6-month-old female Pomeranian with tetraplegia as a clinical sign. Lateral survey radiography of the neck with flexion revealed atlantoaxial subluxation with ventral subluxation of C2. Computed tomography revealed absence of dens and atlanto-occipital overlapping. Magnetic resonance imaging showed compression of the spinal cord and indentation of caudal cerebellum. The diagnosis was Chiari-like malformation, atlantoaxial subluxation with ventral displacement of C2, atlanto-occipital overlapping, and syringomyelia. The dog underwent foramen magnum decompression, dorsal laminectomy of C1, and ventral fixation of the atlantoaxial joint. Soon after the operation, voluntary movements of the legs were recovered. Finally, the dog could stand and walk without assistance. The dog had complicated malformations at the craniocervical junction but foramen magnum decompression and dorsal laminectomy for Chiari-like malformation, and ventral fixation for atlantoaxial subluxation resulted in an excellent clinical outcome.

Single-Cell Phosphospecific Flow Cytometric Analysis of Canine and Murine Adipose-Derived Stem Cells

This study aimed to demonstrate single-cell phosphospecific flow cytometric analysis of canine and murine adipose-derived stem/stromal cells (ADSCs). ADSCs were obtained from clinically healthy laboratory beagles and C57BL/6 mice. Cell differentiation into adipocytes, osteocytes, and chondrocytes was observed for the cultured canine ADSCs (cADSCs) and murine ADSCs (mADSCs) to determine their multipotency. We also performed single-cell phosphospecific flow cytometric analysis related to cell differentiation and stemness. Cultured cADSCs and mADSCs exhibited the potential to differentiate into adipocytes, osteocytes, and chondrocytes. In addition, single-cell phosphospecific flow cytometric analysis revealed similar β-catenin and Akt phosphorylation between mADSCs and cADSCs. On the other hand, it showed the phosphorylation of different Stat proteins. It was determined that cADSCs and mADSCs show the potential to differentiate into adipocytes, osteocytes, and chondrocytes. Furthermore, a difference in protein phosphorylation between undifferentiated cADSCs and mADSCs was identified.

Identification of rhodamine 123-positive stem cell subpopulations in canine hepatocellular carcinoma cells

The majority of cases of chemotherapy for hepatocellular carcinoma (HCC) are not effective in human or veterinary medicine due to resistance against anticancer agents. In human medicine, hepatocellular carcinoma stem cells (HCSCs) were recently identified as cytokeratin 19 (CK19)-, cluster of differentiation (CD)-44-, and CD133-positive. However, there are few previous reports regarding canine HCSC (cHCSC). Additionally, to the best of our knowledge, the chemoresistance against anticancer agents of these cHCSCs has not been investigated. In the present study staining of cHCSCs was performed with rhodamine 123, a low-toxicity fluorescent dye for mitochondria, by flow cytometry. There were two subpopulations in the HCC cell line defined by their higher (RhoHi) and lower (RhoLo) fluorescence intensity of rhodamine 123. The RhoHi subpopulation demonstrated a higher Nanog gene expression, sphere-forming ability, and chemoresistance against gemcitabine. However, there was no significant difference between RhoHi and RhoLo regarding the proliferation rate and chemoresistance against mitoxantrone and doxorubicin. The present results indicate that the expression of rhodamine 123 identifies different stem cell subpopulations in a canine HCC cell line.

Computed tomography and magnetic resonance imaging of thoracic chordoma in a Bengal tiger (Panthera tigris tigris).

A Bengal tiger was presented for evaluation of weakness, ataxia and inappetance. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a mass extending from the T7-8 vertebral body to the left rib and compressing the spinal cord. On CT, the bone destruction and sequestrum were shown. On MRI, the multilobulated mass appeared hypo- to isointense in T1-weighted and hyperintense in T2-weighted images. The tiger died after imaging, most likely from renal failure. Chordoma without metastasis was diagnosed on necropsy. The imaging characteristics were similar to those found in chordoma in humans. This report describes the use of CT and MRI in an exotic species.

Chordoma of the thoracic vertebrae in a Bengal tiger (Panthera tigris tigris)

A 19-year-old female Bengal tiger (Panthera tigris tigris) was presented with hind limb weakness, ataxia and respiratory distress. Computed tomography revealed a mass between the left side of the T7 vertebra and the base of the left 7th rib. The tiger then died, and necropsy was performed. Grossly, the vertebral mass was 6 × 5.7 × 3 cm, and invaded the adjacent vertebral bone and compressed the T7 spinal cord. Histologically, the mass was composed of large, clear, vacuolated and polygonal cells with osteochondral matrix. Cellular and nuclear atypia were moderate. The vacuolated cells stained positively for cytokeratin and vimentin and negatively for S-100. Based on these findings, the present case was diagnosed as a vertebral chordoma; the first report in a tiger.