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1.
J Gen Virol ; 101(10): 1027-1036, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32706330

RESUMO

Mammalian orthoreovirus (MRV) has been identified in humans, livestock and wild animals; this wide host range allows individual MRV to transmit into multiple species. Although several interspecies transmission and genetic reassortment events of MRVs among humans, livestock and wildlife have been reported, the genetic diversity and geographic distribution of MRVs in Africa are poorly understood. In this study, we report the first isolation and characterization of MRVs circulating in a pig population in Zambia. In our screening, MRV genomes were detected in 19.7 % (29/147) of faecal samples collected from pigs by reverse transcription PCR. Three infectious MRV strains (MRV-85, MRV-96 and MRV-117) were successfully isolated, and their complete genomes were sequenced. Recombination analyses based on the complete genome sequences of the isolated MRVs demonstrated that MRV-96 shared the S3 segment with a different MRV isolated from bats, and that the L1 and M3 segments of MRV-117 originated from bat and human MRVs, respectively. Our results suggest that the isolated MRVs emerged through genetic reassortment events with interspecies transmission. Given the lack of information regarding MRVs in Africa, further surveillance of MRVs circulating among humans, domestic animals and wildlife is required to assess potential risk for humans and animals.


Assuntos
Fezes/virologia , Orthoreovirus de Mamíferos/genética , Orthoreovirus de Mamíferos/isolamento & purificação , Infecções por Reoviridae/veterinária , Doenças dos Suínos/virologia , Suínos/virologia , Animais , Animais Selvagens/classificação , Animais Selvagens/virologia , Quirópteros/virologia , Genoma Viral , Especificidade de Hospedeiro , Filogenia , Prevalência , Vírus Reordenados/genética , Recombinação Genética , Infecções por Reoviridae/epidemiologia , Infecções por Reoviridae/virologia , Doenças dos Suínos/epidemiologia , Proteínas Virais/genética , Sequenciamento Completo do Genoma , Zâmbia/epidemiologia
2.
BMC Vet Res ; 14(1): 152, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29720166

RESUMO

BACKGROUND: Sodium pentosan polysulfate (NaPPS) was testified as a chondroprotective drug in with a detailed rationale of the disease-modifying activity. This study was undertaken to determine whether anti-osteoarthritis drug, NaPPS inhibited osteoclasts (OC) differentiation and function. Canine bone marrow mononuclear cells (n = 6) were differentiated to OC by maintaining with receptor activator of nuclear factor kappa B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) for up to 7 days with the treatment of NaPPS at concentration of 0, 0.2, 1 and 5 µg/mL. Differentiation and function of OC were accessed using tartrate-resistant acid phosphate (TRAP) staining and bone resorption assay, while monitoring actin ring formation. Invasion and colocalization patterns of fluorescence-labeled NaPPS with transcribed gene in OC were monitored. Gene expression of OC for cathepsin K (CTK), matrix metallopeptidase-9 (MMP-9), nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), c-Fos, activator protein-1(AP-1) and carbonic anhydrase II was examined using real-time PCR. RESULTS: Significant inhibition of OC differentiation was evident at NaPPS concentration of 1 and 5 µg/mL (p < 0.05). In the presence of 0.2 to 5 µg/mL NaPPS, bone resorption was attenuated (p < 0.05), while 1 and 5 µg/mL NaPPS achieved significant reduction of actin ring formation. Intriguingly, fluorescence-labeled NaPPS invaded in to cytoplasm and nucleus while colocalizing with actively transcribed gene. Gene expression of CTK, MMP-9 and NFATc1 were significantly inhibited at 1 and 5 µg/mL (p < 0.05) of NaPPS whereas inhibition of c-Fos and AP-1 was identified only at concentration of 5 µg/mL (p < 0.05). CONCLUSIONS: Taken together, all the results suggest that NaPPS is a novel inhibitor of RANKL and M-CSF-induced CTK, MMP-9, NFATc1, c-Fos, AP-1 upregulation, OC differentiation and bone resorption which might be a beneficial for treatment of inflammatory joint diseases and other bone diseases associated with excessive bone resorption.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Poliéster Sulfúrico de Pentosana/farmacologia , Actinas/metabolismo , Animais , Células Cultivadas , Cães , Humanos , Fator Estimulador de Colônias de Macrófagos/metabolismo , Osteoclastos/citologia , Ligante RANK/metabolismo , Fatores de Transcrição/antagonistas & inibidores
3.
Trop Med Infect Dis ; 9(7)2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39058203

RESUMO

Rabies persists as a longstanding issue in Zambia, despite being preventable. The current control measures, including dog vaccination, population control, and movement restriction, guided by 'The Control of Dogs Act Chapter 247 of the Laws of Zambia', have not yielded the desired impact in many areas of the country including Manyinga and Mwansabombwe districts. These two districts continue to report low dog vaccination rates, unrestricted dog movements, and escalating cases of animal and human rabies, along with dog bites. Aligned with global aspirations to achieve zero human rabies cases by 2030, this study scrutinizes the determinants and obstacles hampering the execution of rabies control initiatives in Manyinga and Mwansabombwe. Spanning approximately 11 months, this cross-sectional study gathered pre- and post-vaccination data from 301 households in Manyinga and 100 households in Mwansabombwe. Questionnaires probed knowledge, attitudes, and practices related to rabies prevention and control. A transect survey, key informant interviews, and assessment of rabies vaccination and dog bite records complemented the data collection. Findings revealed that 88.0% of respondents from both districts possessed knowledge about rabies, confirming affected species and transmission. Moreover, 76.8% in Manyinga and 88.6% in Mwansabombwe were acquainted with rabies prevention and control methods. Concerning dog owners, 89.0% were aware of rabies, 66.0% understood its prevention and control, and the majority identified bites as the primary mode of transmission. Despite the high level of knowledge recorded during the survey, the implementation of preventive measures was low, which was attributed to low levels of law enforcement by the local government authority, inadequate staffing in the veterinary department, unwillingness to pay for dog vaccinations, and unavailability of rabies vaccine at the veterinary office in both districts. Vaccination coverage stood at 64.0% in Manyinga and 21.0% in Mwansabombwe. Notably, education and occupation exhibited a positive significant association with rabies knowledge. In terms of dog bite cases, Manyinga recorded 538 dog bite cases from 2017 to June 2022, while Mwansabombwe recorded 81 dog bite and 23 jackal bite cases from 2021 to June 2022. The study underscores critical knowledge gaps in rural areas and emphasizes the imperative for enhanced public education and awareness programs, improved rabies surveillance, free mass vaccination campaigns, and community engagement to augment vaccination coverage and knowledge about rabies.

4.
J Vet Med Sci ; 85(4): 515-522, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-36889691

RESUMO

Bupivacaine, levobupivacaine and ropivacaine are potent, long acting, amide-type local anesthetics that have several clinical applications including intra-articular administration. The objectives of this study were to evaluate their in vitro effects on cell viability and caspase activity to elucidate whether they activate the extrinsic or intrinsic pathways of apoptosis in canine articular chondrocytes. Chondrocytes in monolayer culture were treated with culture medium as the control, or with 0.062% (0.62 mg/mL) bupivacaine, 0.062% levobupivacaine, and 0.062% ropivacaine for 24 hr. Cell viability was evaluated using the live/dead, 3-(4,5-dimehylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT), and Cell Counting Kit-8 (CCK-8) assays. Evaluation of caspase-3, caspase-8, and caspase-9 activity was performed using colorimetric assays. The MTT and CCK-8 assays were used to evaluate the effect of caspase inhibitors on local anesthetic chondrotoxicity. All three local anesthetics decreased chondrocyte viability after 24 hr (P<0.001). Apoptosis was induced through both the extrinsic and intrinsic pathways. Bupivacaine increased caspase-3, caspase-8, and caspase-9 activity (P<0.001). Levobupivacaine increased caspase-3 (P=0.03) while ropivacaine did not significantly upregulate activity for all three caspases. Caspase inhibition did not suppress bupivacaine chondrotoxicity whereas inhibition of caspase-8 and caspase-9 decreased ropivacaine chondrotoxicity and mildly attenuated levobupivacaine chondrotoxicity. In summary, the level of chondrotoxicity, the type of caspase activated, the level of caspase activation, and the response to caspase inhibitors was dependent on the type of local anesthetic. Therefore, ropivacaine may be a safer choice for intra-articular administration compared to levobupivacaine and bupivacaine.


Assuntos
Anestésicos Locais , Bupivacaína , Animais , Cães , Ropivacaina/toxicidade , Condrócitos , Levobupivacaína/farmacologia , Caspase 3 , Caspase 9/farmacologia , Caspase 8 , Inibidores de Caspase/farmacologia , Caspases
5.
Antibiotics (Basel) ; 11(7)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35884098

RESUMO

Pigs have been shown to be a reservoir for recently emerging livestock-associated Staphylococcus aureus (LA-SA), including methicillin resistant strains in many countries worldwide. However, there is sparse information about LA-SA strains circulating in Zambia. This study investigated the prevalence, phenotypic and genotypic characteristics of S. aureus from pigs and workers at farms and abattoirs handling pigs in Lusaka Province of Zambia. A total of 492 nasal pig swabs, 53 hand and 53 nasal human swabs were collected from farms and abattoirs in selected districts. Standard microbiological methods were used to isolate and determine antimicrobial susceptibility patterns of S. aureus. Polymerase Chain Reaction was used to confirm the species identity and detect antimicrobial resistance and virulence genes of isolates, whereas genetic diversity was evaluated using spa typing. Overall prevalence of S. aureus was 33.1%, 37.8% for pigs and 11.8% for humans. The isolates were resistant to several antibiotics with resistance ranging from 18% to 98% but were all susceptible to vancomycin. Typical LA-SA spa types were detected. The presence of plasmid mediated resistance genes such as tetM (12.8%), other resistance determinants and immune evasion cluster genes among the isolates is of great public health concern. Thus, continuous surveillance of S. aureus using a "One health" approach is warranted to monitor S.aureus infections and spread of antimicrobial resistance.

6.
Cartilage ; 13(2_suppl): 826S-838S, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33307758

RESUMO

OBJECTIVE: To investigate the role and characterize the molecular mechanisms regulating apoptosis and autophagy in nitric oxide (NO)-induced chondrocyte cell death. DESIGN: Cell apoptosis and autophagy were evaluated in chondrocytes treated with sodium nitroprusside (SNP) combined with the presence or absence of interleukin-1 beta (IL-1ß) and nutrient-deprived conditions. The concentration of nitrite was determined by Griess reaction. Activation of apoptosis and autophagy were determined by immunocytochemistry, Western blot, and quantitative real-time polymerase chain reaction (qPCR) analysis. Flow cytometry and MTT assay were used to assess cell viability. RESULTS: Cotreatment of chondrocytes with SNP and IL-1ß under nutrient-deprived condition potentially enhanced the effect of NO-induced cell death. Immunocytochemistry, Western blot, and qPCR analysis indicated that treatment of chondrocytes with SNP significantly reduced autophagic activity, autophagic flux, and multiple autophagy-related (Atg) genes expression. These findings were associated with an increase in ERK, Akt, and mTOR phosphorylation, whereas autophagy induction through mTOR/p70S6K inhibition by rapamycin significantly suppressed NO-induced cell apoptosis. Furthermore, the cleavage of poly(ADP-ribose) polymerase (PARP) and caspase-3 activation in response to apoptosis was weakly detected. These results corresponded with a significant increase in apoptosis-inducing factor (AIF) expression, suggesting the involvement of the caspase-independent pathway. CONCLUSIONS: These results demonstrate that in chondrocyte cultures with cells induced into an osteoarthritis state, NO inhibits autophagy and induces chondrocyte apoptosis mainly, but not completely through the caspase-independent pathway. Our data suggest that autophagy is a protective mechanism in the pathogenesis of osteoarthritis and could be proposed as a therapeutic target for degenerative joint diseases.


Assuntos
Condrócitos , Osteoartrite , Apoptose , Autofagia/fisiologia , Condrócitos/metabolismo , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacologia , Óxido Nítrico/uso terapêutico , Osteoartrite/tratamento farmacológico
7.
J Vet Med Sci ; 82(8): 1209-1218, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32641601

RESUMO

Pentosan polysulfate (PPS) is a semi-synthetic sulfated polysaccharide compound which has been shown the benefits on therapeutic treatment for osteoarthritis (OA) and has been proposed as a disease modifying osteoarthritis drugs (DMOADs). This study investigated the effects of PPS on cell proliferation, particularly in cell cycle modulation and phenotype promotion of canine articular chondrocytes (AC). Canine AC were treated with PPS (0-80 µg/ml) for 24, 48 and 72 hr. The effect of PPS on cell viability, cell proliferation and cell cycle distribution were analyzed by MTT assay, DNA quantification and flow cytometry. Chondrocyte phenotype was analyzed by quantitative real-time PCR (qPCR) and glycosaminoglycan (GAG) quantification. PPS significantly reduced AC proliferation through cell cycle modulation particularly by maintaining a significantly higher proportion of chondrocytes in the G1 phase and a significantly lower proportion in the S phase of the cell cycle in a concentration- and time-dependent manner. While the proportion of chondrocytes in G1 phase corresponded with the significant downregulation of cyclin-dependent kinase (CDK) 1 and 4. Furthermore, the study confirms that PPS promotes a chondrogenic phenotype of AC through significant upregulation of collagen type II (Col2A1) mRNA and GAG synthesis. The effect of PPS on the inhibition of chondrocyte proliferation while promoting a chondrocyte phenotype could be beneficial in the early stages of OA treatment, which transient increase in proliferative activity of chondrocytes with subsequent phenotypic shift and less productive in an essential component of extracellular matrix (ECM) is observed.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Poliéster Sulfúrico de Pentosana/farmacologia , Animais , Cartilagem Articular/citologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrogênese/efeitos dos fármacos , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Cães , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoartrite/veterinária
8.
J Vet Med Sci ; 82(6): 793-803, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32350166

RESUMO

This study investigated the effects of culture time on phenotype stability of canine articular chondrocytes (CACs) in non-passaged long-term monolayer culture. Third passage (P3) CACs isolated from four cartilage samples were seeded at three different initial seeding densities (0.2 × 104, 1.0 × 104 and 5.0 × 104 cells/cm2) and maintained in monolayer condition up to 8 weeks without undergoing subculture after confluence. The characteristic changes of chondrocytes during the culture period were evaluated based on the cell morphology, cell proliferation, glycosaminoglycans (GAGs) content, DNA quantification, mRNA expression and ultrastructure of chondrocytes. Chondrocytes maintained under post-confluence condition exhibited a capability to grow and proliferate up to 4 weeks. Alcian blue staining and Dimethylmethylene blue (DMMB) assay revealed that the extracellular matrix (ECM) synthesis was increased in a time-dependent manner from 2 to 8 weeks. The chondrocyte mRNA expression profile was dramatically affected by prolonged culture time, with a significant downregulation of collagen type I, whereas the expression of collagen type II, aggrecan, Sox9 and matrix metalloproteinase 13 (MMP-13) were significantly upregulated. In addition, transmission electron microscopy (TEM) result indicated dilation of rough endoplasmic reticulum (RER) in these long-term monolayer cultured chondrocytes. These findings demonstrate that the chondrocytes phenotype could be partially redifferentiated through the spontaneous redifferentiation process in long-term cultures using standard culture medium without the addition of chondrogenic supplements or tissue-culture scaffolds.


Assuntos
Cartilagem Articular/citologia , Diferenciação Celular , Condrócitos/citologia , Animais , Cartilagem Articular/metabolismo , Técnicas de Cultura de Células/métodos , Proliferação de Células , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/ultraestrutura , Colágeno/biossíntese , Cães , Matriz Extracelular/metabolismo , Glicosaminoglicanos/análise , Microscopia Eletrônica de Transmissão , RNA Mensageiro/metabolismo
9.
Res Vet Sci ; 122: 179-185, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529273

RESUMO

Pentosan polysulfate (PPS) is currently under investigation as a potential disease-modifying antiarthritic agent. In the present study the effects of PPS on arthritic profiles based on clinical score, ankle size, histological changes, and activity of inflammatory mediators using collagen-induced arthritic rat are reported. Model of arthritis was developed in Sprague Dawley rats by intradermal injection of bovine type II collagen emulsified with incomplete Freund's adjuvant. The rats were randomly divided into four groups: normal control, arthritic control, arthritic rats treated with PPS (at dose level 20 µg/g) and arthritic rats treated with meloxicam (2 µg/g). The treatment was continued daily until the day 30. Arthritic biomarkers (cartilage oligomeric matrix protein and tartrate-resistant acid phosphatase 5b) in synovial fluid, expression of inflammatory mediators (interleukin-1ß, and tumor necrosis factor-α) and osteoclast marker genes (cathepsin K, tartrate-resistant acid phosphatase) in synovial membrane were measured. Daily administration of PPS to the arthritic rats significantly decreased the severity of arthritis by effectively suppressing the symptoms of arthritis and improving the functional recovery based on clinical score and histopathological evidence. Intriguingly, identical downregulation pattern of arthritis profiles, biological markers as well as relative mRNA levels of osteoclast markers and cytokines were monitored in arthritic rats treated with PPS. In conclusion, PPS exerted protective effects against collagen-induced arthritis in rats. The results suggest that PPS acts as an anti-inflammatory and anti-arthritic agent in decreasing the arthritic effects in collagen-induced arthritic rats.


Assuntos
Artrite Experimental/tratamento farmacológico , Colágeno Tipo II/toxicidade , Poliéster Sulfúrico de Pentosana/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Bovinos , Colágeno Tipo II/química , Citocinas/genética , Citocinas/metabolismo , Adjuvante de Freund , Regulação da Expressão Gênica/efeitos dos fármacos , Lipídeos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/uso terapêutico
10.
J Vet Med Sci ; 80(11): 1681-1687, 2018 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-30210068

RESUMO

Although chondroinductive growth factors are considered necessary for chondrogenesis of bone marrow-derived mesenchymal stem cells (BMSC), independent and spontaneous chondrogenesis has been previously demonstrated in adult horses, bovine calves and adult human BMSC. Surprisingly, adult canine BMSC under similar culture conditions previously failed to demonstrate chondrogenesis. The present study evaluated independent chondrogenic potential of BMSC sourced from three young dogs in the absence of known chondroinductive factors. BMSC were culture expanded in 10% DMEM up to third passage (P3). At each passage, the phenotype of BMSC was evaluated by RT-PCR gel electrophoresis and qPCR. BMSC exhibited a chondrogenic phenotype in the absence of dexamethasone and TGF-ß1 as verified by the expression of Sox-9, type II collagen and aggrecan. Sox-9 was significantly downregulated (P<0.05) from P1-P3 compared to P0 while type II and X collagen, and aggrecan were significantly downregulated at P3 compared to P0. There was a significant (P<0.01) negative correlation between passaging and Sox-9, type II collagen and aggrecan gene expression. These results indicate that independent chondrogenic potential and phenotype retention of BMSC decreases in a passage-dependent pattern. Therefore, caution should be exercised for future experiments evaluating the chondrogenic potential of BMSC after extensive expansion cultures in 10% DMEM.


Assuntos
Condrogênese , Cães/anatomia & histologia , Células-Tronco Mesenquimais/citologia , Animais , Técnicas de Cultura de Células , Proliferação de Células , Dexametasona/farmacologia , Inoculações Seriadas , Fator de Crescimento Transformador beta1/farmacologia
11.
Res Vet Sci ; 114: 370-377, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28711819

RESUMO

The objective of this study was to assess the differentiation capability of synoviocytes derived from dogs with inflammatory joint conditions. Cranial cruciate ligament ruptured (CCLr) (n=12) and medial patella luxated (MPL) (n=10) knee joints of the dogs were used to collect the synovial membrane (SM). Synoviocytes were enzymatically released from the SM and analyzed by flow cytometry for specific cellular markers (CD44 and CD90) of mesenchymal stem cells (MSCs), while doing histopathology from another part of SM sections. Under specific culture conditions, synoviocytes were forced to differentiate into chondrogenesis, adipogenesis, osteogenesis and osteoclastogenesis to investigate the multipotency. Upon treatments phenotypes of cell cultures were analyzed by histopathology and by semi-quantitative reverse transcriptase polymerase chain reaction for the expression of each differentiation marker genes. Although flow cytometry showing similar MSCs populations in CCLr and MPL synovium, synovial cells derived from CCLr showed higher multipotency compared to MPL-derived samples. Further, synovial changes such as vascularity, mononuclear cell infiltration and cellular hypertrophy were more pronounced in CCLr-derived synovial tissue than in MPL. Taken together, these findings suggested that the differentiation capability of SM-derived multipotent stem cells varies with inflammatory severity occurring in different joint conditions.


Assuntos
Lesões do Ligamento Cruzado Anterior/veterinária , Diferenciação Celular , Doenças do Cão/metabolismo , Luxações Articulares/etiologia , Células-Tronco Mesenquimais/fisiologia , Ruptura/veterinária , Sinoviócitos/metabolismo , Animais , Lesões do Ligamento Cruzado Anterior/etiologia , Doenças do Cão/etiologia , Cães/lesões , Feminino , Inflamação/etiologia , Inflamação/veterinária , Luxações Articulares/veterinária , Masculino , Patela/fisiopatologia , Ruptura/etiologia
12.
J Vet Med Sci ; 79(7): 1182-1190, 2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28552861

RESUMO

Mesenchymal stem cells (MSC) are a potential alternative source of differentiated chondrocytes for cartilage tissue regeneration and repair of osteoarthritic (OA) joints. We investigated the effects of pentosan polysulfate (PPS) and polysulfated glycosaminoglycan (PSGAG) on chondrogenesis of canine bone marrow-derived mesenchymal stem cells (cBMSC) in alginate and micromass cultures (MMC). Chondrogenic differentiation medium (CDM) was supplemented with PPS or PSGAG at concentrations of 0 (positive control; PC), 1, 3 and 5 µg/ml. 10% DMEM was used as negative control. Chondrocyte phenotype was analyzed by quantitative real-time PCR (qPCR) for alginate cultures and Alcian blue staining for proteoglycan (PG) synthesis for MMC. In alginate culture, PPS and PSGAG showed no significant effect on type II collagen, aggrecan and HIF-2α mRNA expression. PPS had no significant effect on type I collagen whereas PSGAG significantly upregulated (P<0.05) it at all concentrations relative to other treatments. PPS demonstrated a dose-dependent inhibitory effect on type X collagen mRNA with significant inhibition observed at 5 µg/ml compared to the NC. PSGAG showed an inverse effect on type X collagen with 1 µg/ml significantly inhibiting its expression while increase in the concentration correspondingly increased type X collagen expression. In MMC, PPS significantly enhanced chondrogenesis and PG deposition whereas PSGAG inhibited chondrogenesis and promoted a fibrocartilage-like phenotype with reduced PG deposition. While PPS enhances chondrogenesis of cBMSC in MMC, the response of MSC to chondroinductive factors is culture system-dependent and varies significantly between alginate and MMC.


Assuntos
Condrogênese/efeitos dos fármacos , Glicosaminoglicanos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Poliéster Sulfúrico de Pentosana/farmacologia , Alginatos , Animais , Células Cultivadas , Condrócitos/efeitos dos fármacos , Doenças do Cão/terapia , Cães , Ácido Glucurônico , Ácidos Hexurônicos , Osteoartrite/terapia , Osteoartrite/veterinária , Reação em Cadeia da Polimerase em Tempo Real
13.
PLoS One ; 12(5): e0177144, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28472120

RESUMO

Osteoarthritic (OA) chondrocytes are shown to express inducible nitric oxide synthase (iNOS) which produces high concentrations of nitric oxide (NO), particularly when stimulated with proinflammatory cytokines. NO is involved in OA cartilage degradation. On the other hand, c-Jun N-terminal Kinase (JNK) pathway mediates the activation and transcription of c-Jun, which is required for interleukin-1 (IL-1)-induction of matrix metalloproteinases-13 (MMP-13) in OA pathogenesis. Therefore, the selective inhibition of iNOS and c-Jun is a promising target for treatment and prevention of OA. The purpose of the study was to investigate the inhibitory effects of pentosan polysulfate (PPS) on IL-1ß-induced iNOS, c-Jun and HIF-α isoforms upregulation in canine articular chondrocytes (CACs). Primary (P0) chondrocytes were isolated and cultured from femoral head cartilages of three (3) dogs. First passage (P1) chondrocytes were preincubated with 0, 1, 5, 15 and 40 µg/mL of PPS for 4 hr before treatment with 10 ng/mL rhIL-1ß for a further 8 hr. In addition, we evaluated the effects of single and multiple cytokine with or without LPS on iNOS protein induction. PPS significantly inhibited (P < 0.05) IL-1ß-induced iNOS, c-Jun and HIF-1α mRNA upregulation in a dose-dependent pattern. iNOS mRNA was significantly inhibited at 15 and 40 µg/mL whereas c-Jun and HIF-1α were significantly downregulated at 5, 15 and 40 µg/mL of PPS compared to chondrocytes treated with only rhIL-1ß. Intriguingly, CACs were recalcitrant to single IL-1ß, TNF-α or LPS-induction of iNOS protein including to a combination of IL-1ß+TNF-α, IL-1ß+LPS except to TNF-α+LPS and IL-1ß+TNF-α+LPS suggestive of a protective mechanism from iNOS detrimental effects on perpetuating OA. IL-1ß+TNF-α+LPS-induced iNOS protein expression was significantly abrogated by PPS. We demonstrate for the first time that PPS is a novel inhibitor of IL-1ß-induced iNOS, c-Jun, and HIF-1α mRNA upregulation and iNOS protein induction which may be beneficial for prevention and treatment OA.


Assuntos
Cartilagem Articular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Genes jun , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Interleucina-1beta/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/genética , Poliéster Sulfúrico de Pentosana/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Cães , Interleucina-1beta/fisiologia , RNA Mensageiro/genética , Regulação para Cima/fisiologia
14.
J Vet Med Sci ; 79(12): 2030-2035, 2017 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-29109351

RESUMO

The aim of this study was to investigate osteoclastogenic properties of inflammatory cytokines at different time-points of osteoclastogenesis. Bone marrow-derived macrophages from five healthy dogs were stimulated with the macrophage colony-stimulating factor, receptor activator of nuclear factor-κB ligand and inflammatory cytokines such as interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and IL-17. Osteoclasts (OC) formation and function were enhanced with TNF-α regardless of temporal differences. But in contrast, IL-1ß suppressed the osteoclastogenesis at early phase of the process while upregulating at the late phase. Furthermore, differentiation of OC precursors into OC was suppressed at high concentrations of IL-17. Collectively, the results revealed that suppressing TNF-α would be a promising strategy to inhibit inflammation-associated bone destruction in dogs.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Citocinas/farmacologia , Macrófagos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Ligante RANK/farmacologia , Animais , Células da Medula Óssea/citologia , Cães , Interleucina-17/farmacologia , Interleucina-1beta/farmacologia , Fator de Necrose Tumoral alfa/farmacologia
15.
Prev Vet Med ; 100(3-4): 252-5, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21612833

RESUMO

Faecal samples were collected from January 2010 through September 2010 to determine the prevalence of gastrointestinal (GI) helminths infestation in dogs in urban Lusaka and rural Katete Districts of Zambia. A total of 452 faecal samples (n=160 Katete, n=292 Lusaka) were examined by faecal flotation for the presence of helminth eggs and 82.5% of dogs were positive for GI helminths in Katete compared to 76% for Lusaka. Positive results with the presence of at least one parasite corresponded to 72.9% Ancylostoma caninum, 11% Toxocara canis, 4.8% Toxascaris leonina, 2.4% Dipylidium caninum, 0.7% Taeniidae and 0.3% T. vulpis, species for Lusaka while Katete recorded 70.6% A. caninum, 18.1% T. vulpis, 11.1% T. canis, 13.1% D. caninum, 3.8% T. leonina, and 0.6% Taeniidae. Except for T. vulpis and D. caninum (p<0.05) the results indicated no significant difference in the prevalence of the identified GI helminth between Lusaka and Katete. There was no significant difference in the prevalence between genders of GI helminth infestation demonstrated in this study and only A. caninum showed significant difference in prevalence by age category. The study also showed the presence of zoonotic intestinal helminths A. caninum, T. canis and D. caninum. The study highlights that there was no significant difference in spectrum and prevalence of GI helminths between urban and rural areas in Zambia. It further brings to light the importance of educating owners of dogs on the importance of regular deworming of dogs and control of ectoparasites in order to minimise the risk that these dogs pose to them and the public.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Gastroenteropatias/veterinária , Helmintos/isolamento & purificação , Análise de Variância , Animais , Cães , Fezes/parasitologia , Feminino , Gastroenteropatias/epidemiologia , Gastroenteropatias/parasitologia , Masculino , Prevalência , População Rural , População Urbana , Zâmbia/epidemiologia
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