Blood vessel organoids generated by base editing and harboring single nucleotide variation in Notch3 effectively recapitulate CADASIL-related pathogenesis.

Human blood vessel organoids (hBVOs) offer a promising platform for investigating vascular diseases and identifying therapeutic targets. In this study, we focused on in vitro modeling and therapeutic target finding of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the most common form of hereditary stroke disorder caused by mutations in the NOTCH3 gene. Despite the identification of these mutations, the underlying pathological mechanism is elusive, and effective therapeutic approaches are lacking. CADASIL primarily affects the blood vessels in the brain, leading to ischemic strokes, migraines, and dementia. By employing CRISPR/Cas9 base-editing technology, we generated human induced pluripotent stem cells (hiPSCs) carrying Notch3 mutations. These mutant hiPSCs were differentiated into hBVOs. The NOTCH3 mutated hBVOs exhibited CADASIL-like pathology, characterized by a reduced vessel diameter and degeneration of mural cells. Furthermore, we observed an accumulation of Notch3 extracellular domain (Notch3ECD), increased apoptosis, and cytoskeletal alterations in the NOTCH3 mutant hBVOs. Notably, treatment with ROCK inhibitors partially restored the disconnection between endothelial cells and mural cells in the mutant hBVOs. These findings shed light on the pathogenesis of CADASIL and highlight the potential of hBVOs for studying and developing therapeutic interventions for this debilitating human vascular disorder.

Effect of the sodium-glucose cotransporter-2 inhibitor, DWP16001, as an add-on therapy to insulin for diabetic dogs: A pilot study.

BACKGROUND: Sodium-glucose cotransporter-2 (SGLT2) inhibitors are a novel class of anti-hyperglycaemic agents. OBJECTIVE: This study aimed to evaluate the safety and the adjuvant glycaemic control effect of an SGLT2 inhibitor, DWP16001, in diabetic dogs receiving insulin treatment. METHODS: Nineteen diabetic dogs receiving insulin treatment (NPH, porcine lente and glargine insulin) were divided into two groups according to dosing frequency: DWP TOD group (n = 10) and DWP SID group (n = 9). In the DWP TOD group, 0.025 mg/kg of DWP16001 was administered once every 3 days, whereas, in the DWP SID group, 0.025 mg/kg of DWP16001 was administered once a day. Food intake was maintained during the trial period. Hypoglycaemia, ketoacidosis or unexpected life-threatening reactions were assessed as adverse effects before and after DWP16001 administration. We compared insulin requirement reduction and blood glucose level control between two groups. RESULTS: No specific adverse effects were observed during the clinical trial, and haematological parameter remained unchanged. Moreover, the fasting glucose levels and daily insulin dose in the DWP TOD group were lower than the pre-administration values, but not significantly different for 8 weeks. Systolic blood pressure, fructosamine and insulin dose decreased significantly in the DWP SID group compared to the DWP TOD group at 8 weeks (p < 0.05) without affecting food consumption. Among these patients, 10 patients were monitored while receiving DWP16001 for 12 months (DWP TOD group n = 5, DWP SID group n = 5). The fasting glucose and fructosamine levels and daily insulin dose were reduced in both groups at 12 months compared with those before receiving DWP16001. CONCLUSION: When DWP16001, an SGLT2 inhibitor, was supplied to dogs with type 1 diabetes, no adverse effects were observed, and it was confirmed that the administered insulin dose can be reduced in controlling blood glucose.

In vitro evaluation of the antitumor activity of axitinib in canine mammary gland tumor cell lines.

BACKGROUND: Axitinib, a potent and selective inhibitor of vascular endothelial growth factor (VEGF) receptor (VEGFR) tyrosine kinase 1,2 and 3, is used in chemotherapy because it inhibits tumor angiogenesis by blocking the VEGF/VEGFR pathway. In veterinary medicine, attempts have been made to apply tyrosine kinase inhibitors with anti-angiogenic effects to tumor patients, but there are no studies on axitinib in canine mammary gland tumors (MGTs). OBJECTIVES: This study aimed to confirm the antitumor activity of axitinib in canine mammary gland cell lines. METHODS: We treated canine MGT cell lines (CIPp and CIPm) with axitinib and conducted CCK, wound healing, apoptosis, and cell cycle assays. Additionally, we evaluated the expression levels of angiogenesis-associated factors, including VEGFs, PDGF-A, FGF-2, and TGF-ß1, using quantitative real-time polymerase chain reaction. Furthermore, we collected canine peripheral blood mononuclear cells (PBMCs), activated them with concanavalin A (ConA) and lipopolysaccharide (LPS), and then treated them with axitinib to investigate changes in viability. RESULTS: When axitinib was administered to CIPp and CIPm, cell viability significantly decreased at 24, 48, and 72 h (p < 0.001), and migration was markedly reduced (6 h, p < 0.05; 12 h, p < 0.005). The apoptosis rate significantly increased (p < 0.01), and the G2/M phase ratio showed a significant increase (p < 0.001). Additionally, there was no significant change in the viability of canine PBMCs treated with LPS and ConA. CONCLUSION: In this study, we confirmed the antitumor activity of axitinib against canine MGT cell lines. Accordingly, we suggest that axitinib can be applied as a new treatment for patients with canine MGTs.

Anti-cancer effects of DHP107 on canine mammary gland cancer examined through in-vitro and in-vivo mouse xenograft models.

BACKGROUND: Canine mammary gland cancer (CMGC) is a common neoplasm in intact bitches. However, the benefit of adjuvant chemotherapy is unclear. The aim of this study was to investigate the anti-proliferative effects of paclitaxel on CMGC in in-vitro and in-vivo settings. RESULTS: Paclitaxel dose-dependently inhibited viability and induced G2/M phase cell cycle arrest and apoptosis in both primary and metastatic CMGC cell lines (CIPp and CIPm). In animal experiments, the average tumour volume decreased significantly in proportion to the administered oral paclitaxel dose. By examining tumour tissue using a TUNEL assay and immunohistochemical staining with anti-CD31 as a marker of endothelial differentiation, respectively, it was confirmed that oral paclitaxel induced apoptosis and exerted an anti-angiogenetic effect in tumour tissues. Further, downregulation of cyclin D1 in tumour tissues suggested that oral paclitaxel induced cell cycle arrest in tumour tissues in-vivo. CONCLUSIONS: Our results suggest that paclitaxel may have anti-cancer effects on CMGC through cell cycle arrest, induction of apoptosis, and anti-angiogenesis. This study could provide a novel approach to treat CMGC.

Anticancer effect of superoxide dismutase on canine mammary gland tumour in vitro.

BACKGROUND: Reactive oxygen species (ROS) have been shown to promote tumour growth and metastasis in human cell lines. The superoxide anion (•O2 - ) is produced during ROS formation and is involved in tumour cell signalling. OBJECTIVES: Superoxide dismutase (SOD) has been applied to canine mammary gland tumours to investigate its antitumour effects in vitro. METHODS: Cell proliferation, cell cycle cell migration assays, reverse transcription-quantitative polymerase chain reaction, and western blot analysis were performed to determine the effects of SOD on canine mammary tumour cell line. RESULTS: SOD treatment resulted in anti-proliferative effects and mediated cell cycle arrest in the canine mammary gland tumour cell lines (CIPp and CIPm). It also downregulated the expression of N-cadherin and Vimentin. CONCLUSIONS: The results confirmed that SOD inhibits tumour cell proliferation and migration, thus supporting the potential applications of SOD as a chemotherapeutic agent for canine mammary gland tumours.

Changes in Urinary Exosomal Nuclear Matrix Protein-22 in Dogs With Urothelial Carcinoma: A Pilot Study.

BACKGROUND/AIM: Nuclear matrix protein-22 (NMP-22) is widely used in human medicine as a prognostic and diagnostic tool for urothelial carcinoma (UC). In addition, the use of urinary exosomes as a liquid biopsy tool is emerging for the diagnosis of certain types of cancer in human medicine. This study aimed to investigate the change in urinary exosomal NMP-22 for the diagnosis of UC in dogs. PATIENTS AND METHODS: Among canine patients who visited the veterinary hospital, urine was collected from those whose owners provided consent. A total of 23 dogs (UC group, n=6; control group, n=17) were included in the analysis. After exosomes were isolated from the urine, NMP-22 was measured using enzyme-linked immunosorbent assay. RESULTS: In the UC group, the expression of NMP-22 in urinary exosomes was significantly higher than that in non-UC groups (p<0.0001). CONCLUSION: NMP-22 is significantly increased in exosomes in the urine of dogs diagnosed with UC, suggesting that urinary exosome NMP-22 can be considered as one of the liquid biopsy tools for diagnosing UC in dogs.

Retrospective evaluation of prognosis and survival with various immunosuppressants in 82 dogs diagnosed with meningoencephalitis of unknown etiology (2010-2021).

BACKGROUND: Meningoencephalomyelitis of unknown etiology (MUE) is a comprehensive term for non-infectious inflammatory brain diseases of the central nervous system (CNS) caused by abnormal autoimmune responses. This study aims to compare the differences in survival and clinical response of MUE according to the adjuvant immunosuppressant use. Medical records of 82 dogs diagnosed with MUE were reviewed retrospectively. RESULTS: The overall survival time was 769 days (range 14-2687 days). The median survival time for each adjunctive was: leflunomide 1035 days (range 126-2163 days), mycophenolate mofetil 865 days (range 39-2191 days), cyclosporin 441 days (range 11-2176 days), cytosine arabinoside 754 days (range 6-1898 days) and a combination of mycophenolate mofetil and cytosine arabinoside 132 days (range 23-1227 days). There was no significant difference in the incidence rate of adverse events according to the immunosuppressants, but moderate to severe anemia was confirmed in 3 patients (18.7%) in the leflunomide group. CONCLUSIONS: The survival time and response rate of MUE dogs differed depending on which adjunctive immunosuppressants were used. Leflunomide showed a long survival time and a relatively good response rate in dogs with MUE. However, a large-scale further study with standardized doses of immunosuppressants and supportive treatment and constant monitoring interval is needed.

Case report: Fatal insulin overdose in a dog with type 1 diabetes mellitus-characteristics and successful management.

Administering more than 10 times the therapeutic dose of insulin is extremely rare in diabetic dogs and is life threatening with hypoglycemia and seizures if not accompanied by appropriate treatment. A 15-year-old, castrated male miniature poodle dog managed for diabetes presented with depression, disorientation, ataxia, and cluster seizures. The dog had been administered 11.1 U/kg of neutral protamine hegadorn (NPH) insulin (10 times the prescribed dose) 3 h before the onset of symptoms. Blood analysis revealed hypoglycemia, with a circulating glucose level of <50 mg/dL. To treat the hypoglycemia-induced seizures, dextrose was repeatedly administered intravenously. Repeated generalized seizures were treated with anticonvulsants and intermittent mannitol. Since refractory hypoglycemia persisted 24 h after the insulin overdose, it was decided to proceed with glucagon treatment (15-30 ng/kg/min titrated to the blood glucose level after a loading dose of 50 ng/kg intravenous bolus infusion). After 37 h of glucagon treatment, blood glucose levels stabilized. After entering a hyperglycemic state, NPH insulin was administered to manage insulin-dependent diabetes mellitus. This is the first case documented of successful treatment with glucagon, anticonvulsants and intermittent mannitol for refractory hypoglycemia and seizure caused by fatal insulin overdose. Thus, it has great clinical value in veterinary medicine.

Amelioration of DSS-induced colitis in mice by TNF-α-stimulated mesenchymal stem cells derived from feline adipose tissue via COX-2/PGE2 activation.

BACKGROUND: Mesenchymal stem cells (MSCs) have been investigated as therapeutic agents for inflammatory bowel disease (IBD). Stimulation of MSCs with pro-inflammatory cytokines is an approach to enhance their immunomodulatory effects. However, further investigation is required to support their application in immune-mediated disorders and companion animals. OBJECTIVES: This study aimed to assess the therapeutic effect of tumor necrosis factor (TNF)-α-stimulated feline adipose tissue-derived MSCs (fAT-MSCs) in a dextran sulfate sodium (DSS)-induced colitis mouse model. METHODS: Colitis mice was made by drinking water with 3% DSS and fAT-MSCs were injected intraperitoneally. Colons were collected on day 10. The severity of the disease was evaluated and compared. Raw 264.7 cells were cultured with the conditioned medium to determine the mechanism, using quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: TNF-α-stimulated fAT-MSCs more improved severity of DSS-induced colitis in disease activity, colon length, histologic score, and inflammatory cytokine. In sectionized colon tissues, the group comprising TNF-α-stimulated fAT-MSCs had higher proportion of CD11b+CD206+ macrophages than in the other groups. In vitro, TNF-α-stimulation increased cyclooxygenase-2 (COX-2) expression and prostaglandin E2 (PGE2) secretion from fAT-MSCs. The conditioned medium from TNF-α-stimulated fAT-MSCs enhanced the expression of interleukin-10 and arginase-1 in LPS-activated Raw 264.7 cells. CONCLUSIONS: These results represent that TNF-α-stimulated fat-mscs ameliorate the inflamed colon more effectively. Furthermore, we demonstrated that the effectiveness was interlinked with the COX-2/PGE2 pathway.

Macrophage induces anti-cancer drug resistance in canine mammary gland tumor spheroid.

Tumor-associated macrophages (TAMs) play an important role in the tumor microenvironment by producing cytokines and growth factors. Furthermore, TAMs play multifunctional roles in tumor progression, immune regulation, metastasis, angiogenesis, and chemoresistance. Hypoxia in the tumor microenvironment induces tumor-supporting transformation of TAMs, which enhances tumor malignancy through developing anti-cancer resistance, for example. In this study, a hybrid spheroid model of canine mammary gland tumor (MGT) cell lines (CIPp and CIPm) and canine macrophages (DH82) was established. The effects of hypoxia induced by the spheroid culture system on the anti-cancer drug resistance of canine MGT cells were investigated. A hybrid spheroid was created using an ultralow-adhesion plate. The interactions between canine MGT cells and DH82 were investigated using a co-culture method. When co-cultured with DH82, cell viability and expression levels of tumor growth factors and multi-drug resistance genes were increased in canine MGT cells under doxorubicin. Additionally, doxorubicin-induced apoptosis and G2/M cell cycle arrest were attenuated in canine MGT cells co-cultured with DH82. In conclusion, the hybrid spheroid model established in this study reflects the hypoxic TME, allowing DH82 to induce anti-cancer drug resistance in canine MGT cells.

Changes in Lactate-related Fecal Microbiome in Hyperlactatemia Diabetic Dogs.

BACKGROUND/AIM: The correlation between the intestinal microbiome and endocrine disorders has recently been drawing attention as an important key for determining their pathology and clinical assessment. In this study, we evaluated the microbiome of dogs with insulin-dependent diabetes mellitus (IDDM) with respect to blood lactate. MATERIALS AND METHODS: Fecal samples were obtained from 17 subjects and real-time quantitative polymerase chain reaction determinations were performed to quantify the gene expression levels of lactate-producing and dysbiosis index-related bacteria. RESULTS: Expression levels of the lactate-producing bacteria Lactobacillus spp., Enterococcus spp., and Bifidobacterium spp., were confirmed in patients with high concentrations of lactate in the blood. The abundance of Enterococcus and Bifidobacterium was higher in diabetic dogs compared to that of non-diabetic dogs. When blood lactate concentrations were high, the abundance of Bifidobacterium also increased. CONCLUSION: Blood lactate levels influence the gut microbiome in dogs with IDDM. This study will help understand the gut microbiota in the context of diabetes in human and veterinary medicine.

Tumour necrosis factor stimulated gene 6 intrinsically regulates PD-L1 expressions in breast cancer cells, leading to modulation of tumour microenvironment.

Recent studies have shown that tumour cells express tumour necrosis factor-inducible gene 6 (TSG-6) and its protein, which is known to play a key role in regulating excessive immune responses and proliferation and growth of mesenchymal stem cells (MSCs). It has not been confirmed whether the inhibition of TSG-6 for tumour cells can suppress tumour cell growth and regulate the activation of immune cells in the tumour microenvironment (TME). TSG-6-specific small interfering RNA was transfected into canine and human breast cancer cells (CIPp, CIPm and BT-20). TSG-6-down-regulated (siTSG-6) cells showed decreased cell proliferation, migration, and invasion abilities. Decreased mRNA expressions of NF-κB, STAT3 and Sox2, confirming that TSG-6 is an upper factor governing tumour growth and metastasis. Notably, siTSG-6 cells showed significantly decreased expression levels of CD44 and PD-L1. Direct and indirect co-culture of canine peripheral blood mononuclear cells (cPBMCs) and the siTSG-6 cells showed significant activation in M1 type macrophages and cytotoxic T cells. They also showed a tendency to decrease in the expression of CTLA-4 and increase in the expression of PD-1. In conclusion, this study suggests that the down-regulation of TSG-6 in breast cancer cells could not only suppress tumour growth and metastasis, and but also regulate TME. Since modulation of immune checkpoint proteins occurs in both tumour cells and immune cells, inhibiting TSG-6 and its protein within the TME could be novel therapeutic target for anticancer treatment.

Evaluation of serum interleukin 2 receptor and beta-2-microglobulin as prognostic factors for canine lymphoma: A pilot study.

Interleukin 2 receptor (IL-2R) is released from activated T cell lymphocytes and related to proliferation of B cells and T cells. Beta-2-microglobulin (B2M) is synthesized from all nucleated cells and constitutes a major histocompatibility complex class I antigen. In human medicine, high concentrations of these two factors have been found to be related to prognosis in aggressive non-Hodgkin's lymphoma. In this pilot study, we aimed to assess the correlation between the serum concentration of IL-2R and B2M and the diagnosis and prognosis of canine lymphoma. This study included 8 healthy dogs and 17 dogs with lymphoma. To measure the serum concentration of IL-2R and B2M, a commercial enzyme-linked immunosorbent assay was used. In dogs with lymphoma, IL-2R concentrations were significantly high at the time of diagnosis, but B2M concentrations were not. In relapsed dogs, both IL-2R and B2M concentrations were significantly higher than those in the control and chemotherapy response groups. When the serum concentrations of IL-2R and B2M during chemotherapy were monitored in four relapsed dogs, B2M levels were more closely related with relapse. This study demonstrated that serum IL-2R and B2M concentration can be a diagnostic or prognostic tool for canine lymphoma. Monitoring of serum B2M concentration seems to be useful for predicting relapse.

Hypoxia Increases the Proliferative and Metastatic Ability of Canine Mammary Tumor Cells via Up-regulation of TSG-6.

BACKGROUND/AIM: HIF1α-induced hypoxia is a major characteristic of solid tumors that plays an important role in cancer growth, metastasis, and chronic inflammation. Tumor necrosis factor (TNF) stimulated gene (TSG)-6 is a strong regulator of anti-inflammatory pathways, but its role in cancer cells remains unclear. We hypothesized that hypoxia up-regulates TSG-6, thereby increasing the metastatic and growth potential of cancer cells. MATERIALS AND METHODS: Primary and metastatic canine mammary gland tumor (MGT) cell lines (CIPp and CIPm), were transfected with TSG-6 specific siRNA and treated with cobalt chloride (CoCl2) for 48 h to chemically induce a hypoxia environment. The expression of hypoxia-inducible factor-1-alpha (HIF1α) was evaluated by RT-qPCR and western blot analysis. The metastatic ability of cancer cells and cell cycle distribution were assessed with extracellular matrix invasion assays and flow cytometry. RESULTS: HIF1α up-regulation, induced by CoCl2, was significantly inhibited in the TSG-6-knockdown group in both canine MGT cell lines. The change in the expression levels of HIF1α corresponded to the change of invading cells in the TSG-6-knockdown group. TSG-6-knockdown in the hypoxia group showed decreased proliferation, associated with G2/M phase arrest. CONCLUSION: HIF1α expression in hypoxic condition is regulated by TSG-6 expression in canine MGT. TSG-6-knockdown causes down-regulation of HIF1α, thereby reducing the metastatic and proliferative abilities of cancer cells. TSG-6 in canine MGT has a potential as a therapeutic target in anti-cancer therapy.

Confirmed cases of severe fever with thrombocytopenia syndrome in companion cats with a history of tick exposure in the Republic of Korea.

Severe fever with thrombocytopenia syndrome (SFTS) is a zoonotic disease, and its clinical information and prevalence are important. This study was conducted on 22 feline patients from the Republic of Korea (ROK), suspected to suffer from a tick-borne disease. Four cats were positive for SFTS, and genotypes B-1, B-3, D, and F were identified. Clinical symptoms, such as anorexia, jaundice, thrombocytopenia, leukopenia, and hyperbilirubinemia, were detected. This is the first report of SFTS virus genotypes B-1, D, and F from cats in the ROK. Moreover, our results suggest that jaundice may be an indicator of SFTS in cats.

Effects of Cyclooxygenase-2 in Canine Melanoma-derived Extracellular Vesicles on Tumor Microenvironment In Vitro.

BACKGROUND/AIM: Tumor cell-derived extracellular vesicles (TEVs) promote tumor growth and metastasis; thus, they have drawn the attention of researchers. TEVs regulate the tumor microenvironment by facilitating crosstalk between immune and stromal cells. Macrophages are one of the key components involved in malignant behavior in melanomas. Generally, when activated, macrophages polarize into M1 (pro-inflammatory) or M2 (anti-inflammatory, pro-tumor) phenotypes. However, the role of canine melanoma-derived EVs in macrophage polarization is elusive. In this study, we aimed to analyze the pro- and anti-inflammatory cytokines that are common markers for M1 or M2 macrophages in vitro. MATERIALS AND METHODS: The analysis was performed under coculture conditions of canine melanoma-derived (LMeC) EVs with canine macrophages (DH82). Quantitative reverse transcription polymerase chain reaction, western blotting, and immunofluorescence were used. RESULTS: Canine melanoma-derived EVs polarized M1 macrophages (inducible nitric oxide synthase, tumor necrosis factor α) into M2 macrophages [cluster of differentiation (CD)206, interleukin-10] and cyclooxygenase-2 is a major factor in macrophage polarization in canine melanoma-derived EVs. Furthermore, we also found that melanoma-derived EVs induced the expression of angiogenic cytokines (vascular endothelial growth factor, transforming growth factor ß) in endothelial cells. CONCLUSION: Melanoma-derived EVs perform an immunomodulatory function and can be used as targets in anti-inflammatory treatment.

Isolated hypoaldosteronism managed by DOCP in a dog with chronic kidney disease and hypercortisolism.

A 13-year-old spayed female Schnauzer dog with chronic kidney disease (CKD; International Renal Interest Society stage 2, non-proteinuric, normotensive), diabetes mellitus, hypercortisolism and myxomatous mitral valve degeneration (American College of Veterinary Internal Medicine stage B2) presented with electrolyte imbalance that had progressed to hyperkalaemia and hyponatremia, with a sodium to potassium (Na:K) ratio of 19.6. Cortisol levels after the adrenocorticotropic hormone stimulation test were within the therapeutic range, but aldosterone levels were below the reference range; hence, isolated hypoaldosteronism was diagnosed. After administration of deoxycorticosterone pivalate (DOCP), the electrolyte imbalance improved with a Na:K ratio of 27.7. This is the first report of the management of isolated hypoaldosteronism and hypercortisolism using trilostane and DOCP in a dog. This case highlights the importance of recognizing isolated hypoaldosteronism after long-term treatment with trilostane in a canine patient with CKD.

Maintenance of Hypoimmunogenic Features via Regulation of Endogenous Antigen Processing and Presentation Machinery.

Universally acceptable donor cells have been developed to address the unmet need for immunotypically matched materials for regenerative medicine. Since forced expression of hypoimmunogenic genes represses the immune response, we established universal pluripotent stem cells (PSCs) by replacing endogenous ß2-microglobulin (ß2m) with ß2m directly conjugated to human leukocyte antigen (HLA)-G, thereby simultaneously suppressing HLA-I expression and the natural killer (NK) cell-mediated immune response. These modified human PSCs retained their pluripotency and differentiation capacity; however, surface presentation of HLA-G was absent from subsequently differentiated cells, particularly cells of neural lineages, due to the downregulation of antigen processing and presentation machinery (APM) genes. Induction of APM genes by overexpression of NLR-family CARD domain-containing 5 (NLRC5) or activator subunit of nuclear factor kappa B (NF-κB) heterodimer (RelA) recovered the surface expression of HLA-G and the hypoimmunogenicity of neural cells. Our findings enhance the utility of hypoimmunogenic cells as universal donors and will contribute to the development of off-the-shelf stem-cell therapeutics.

Evaluation of endothelial cell-specific molecule-1 as a biomarker of glycocalyx damage in canine myxomatous mitral valve disease.

BACKGROUND: Endothelial cell-specific molecule-1 (ESM-1) has emerged as a potential biomarker for cardiovascular disease in humans. Myxomatous mitral valve disease (MMVD) is the most common heart disease in dogs, and we hypothesized that MMVD causes chronic inflammation that increases susceptibility to endothelial glycocalyx (eGCX) damage. In this study, we measured the concentration of ESM-1 in a group of dogs with MMVD and evaluated factors affecting eGCX damage. RESULTS: Sixty-four dogs (control, n = 6; MMVD, n = 58) were enrolled in this study. There was no significant difference in serum ESM-1 concentrations among the MMVD stages. The serum ESM-1 concentration was significantly higher in the death group than in the alive group in MMVD dogs. (p = 0.006). In five dogs with MMVD, serum ESM-1 concentrations tended to decrease when the cardiac drug (pimobendan, furosemide, and digoxin) dose was increased. CONCLUSIONS: In cases where MMVD progressed to decompensated heart failure with clinical symptoms and resulted in death, the concentration of serum ESM-1 increased significantly. Therefore, ESM-1 could be utilized as a new potential negative prognostic factor in patients with MMVD.

Retrospective analysis of efficacy and safety of oral paclitaxel for treatment of various cancers in dogs (2017-2021).

BACKGROUND: In humans, several safety evaluations have shown minimal adverse events with oral paclitaxel; however, its therapeutic efficacy and safety has not been well established in dogs with various cancers. OBJECTIVES: We aimed to retrospectively evaluate the efficacy and safety of oral paclitaxel in dogs with various cancers. METHODS: Twenty-one dogs diagnosed with various cancers were administered several doses of oral paclitaxel three times a month (group 1) or six times a month (group 2). RESULTS: The overall response rate was 6.25% (6.25%, complete response; 56.25%, stable disease; 37.5%, progressive disease) in dogs for which the treatment response could be evaluated. The median overall survival (OS) and progression-free survival (PFS) were 74 and 60.5 days, respectively. Regardless of the administration group, differences in OS and PFS of the two groups did not reach statistical significance. Most dogs tolerated the treatment regimen well, and although minor adverse events were observed in some dogs, they recovered after temporary drug discontinuation, dose reduction or symptomatic treatment. There was no significant difference in the prevalence of adverse events between the two groups. CONCLUSIONS: Based on the observed responses in certain types of cancers and the minimal adverse events, the study findings supported the efficacy and safety of oral paclitaxel administration in dogs. Thus, oral paclitaxel could play a role in the management of cancer in dogs.