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The effects of levofloxacin on rabbit anterior cruciate ligament cells in vitro
... Tan et al. (2012) found that levofloxacin significantly reduced cell viability and hyaluronan level, while increasing apoptosis and activecaspase-3 levels in rabbit fibroblast-like synoviocyte cells (FLS) and indicated that levofloxacin have cytotoxic effect on FLS cells. Deng et al. (2011) observed that levofloxacin increased apoptosis in rabbit anteriorcruciate ligament cells (ACL) treated with levofloxacin but reduced the amount of extracellular matrix and they reported that levofloxacin have cytotoxic effect on these cells. Kayraldiz et al. (2017) found that treatment with the different doses of levofloxacin for 24 and 48h did not affect the SCE frequency, but highest levofloxacin concentration (100μg/ml) caused a significant increase in the CA level. ...
... along 2 and 4 weeks, and after one week withdrawal of levofloxacin dosing, there was a significant increase in the CA levels after 2 weeks of levofloxacin dosing in both groups as compared to control group, but after 4 weeks dosing the CA values in both treated groups (G1 and G2) regain normal since the animals of these groups revealed no significant P>0.05 changes after 1 week of levofloxacin withdrawal in comparison with control group. CA results of our study are in consistent with the findings of (Itoh et al., 2002;Shimada et al., 1992;Zhu et al., 2013) from the CHL cells; (Tan et al., 2012;Deng et al., 2011) in rabbit ACL cell, and (Kayraldiz et al., 2017) in human peripheral lymphocytes. Similarly with (Reus et al., 2012;Shimada et al., 1992;Zhu et al., 2013), levofloxacin resulted with no significant increase in MN frequency in all treated animals groups as compared to control group. ...
... There were significant P<0.05 decreases observed in MI and NDI after 4 weeks of treated animals groups as compared to control group with continuous regain to normal values after 1 week of levofloxacin withdrawal in comparison with control group. The study reported cytotoxic effect of levofloxacin same as what they found on FLS and rabbit ACL cells (Tan et al., 2012;Deng et al., 2011), and in contrary to that found by Kayraldiz et al. (2017). Albertini et al. (1995); Oliphant and Green, (2002) describes an evaluation of the predictive capacity of the in vivo rat peripheral lymphocytes using different concentrations of levofloxacin. ...
This study was conducted to evaluate the cytogenetic effects of levofloxacin in male rats. It was carried out on fifty four of the albino male rats, they were divided equally into three main groups and orally dosed levofloxacin and assigned as, the first group was dosed with the therapeutic dose 7.5mg/kg/bw, the second group was dosed with the double therapeutic dose 15mg/kg/bw, the third group was dosed with distilled water and became a control group. The three groups were divided into three subgroups equally according to dosing period of 2 weeks, 4 weeks, 1 week after discontinuation of dosing. Collection of blood and scarification of group animals were done at the end of each period. The results showed, that there were no significant P > 0.05 differences in both the micronuclei assay and in chromosomal aberration among the experimental groups, while the results of both nuclear division index and mitotic index showed, a significant P < 0.05 decrease in their values in both dosed drug groups after the fourth week of the dosage compared to other treated periods and control group. The results of the comet assay showed, varying of results with significant P < 0.05 decreases in both treated groups compared to the control group.We concluded that levofloxacin is a cytotoxic but not genotoxic agent.
... Tan et al. (2012) found that levofloxacin significantly reduced cell viability and hyaluronan level, while increasing apoptosis and activecaspase-3 levels in rabbit fibroblast-like synoviocyte cells (FLS) and indicated that levofloxacin have cytotoxic effect on FLS cells. Deng et al. (2011) observed that levofloxacin increased apoptosis in rabbit anteriorcruciate ligament cells (ACL) treated with levofloxacin but reduced the amount of extracellular matrix and they reported that levofloxacin have cytotoxic effect on these cells. Kayraldiz et al. (2017) found that treatment with the different doses of levofloxacin for 24 and 48h did not affect the SCE frequency, but highest levofloxacin concentration (100μg/ml) caused a significant increase in the CA level. ...
... along 2 and 4 weeks, and after one week withdrawal of levofloxacin dosing, there was a significant increase in the CA levels after 2 weeks of levofloxacin dosing in both groups as compared to control group, but after 4 weeks dosing the CA values in both treated groups (G1 and G2) regain normal since the animals of these groups revealed no significant P>0.05 changes after 1 week of levofloxacin withdrawal in comparison with control group. CA results of our study are in consistent with the findings of (Itoh et al., 2002;Shimada et al., 1992;Zhu et al., 2013) from the CHL cells; (Tan et al., 2012;Deng et al., 2011) in rabbit ACL cell, and (Kayraldiz et al., 2017) in human peripheral lymphocytes. Similarly with (Reus et al., 2012;Shimada et al., 1992;Zhu et al., 2013), levofloxacin resulted with no significant increase in MN frequency in all treated animals groups as compared to control group. ...
... There were significant P<0.05 decreases observed in MI and NDI after 4 weeks of treated animals groups as compared to control group with continuous regain to normal values after 1 week of levofloxacin withdrawal in comparison with control group. The study reported cytotoxic effect of levofloxacin same as what they found on FLS and rabbit ACL cells (Tan et al., 2012;Deng et al., 2011), and in contrary to that found by Kayraldiz et al. (2017). Albertini et al. (1995); Oliphant and Green, (2002) describes an evaluation of the predictive capacity of the in vivo rat peripheral lymphocytes using different concentrations of levofloxacin. ...
This study was carried out to investigate the cytogenetic effect of Levofloxacin after In-ovo inoculation. Forty eight fertilized eggs were used, divided equally into eight groups and inoculated through shell puncture above air cell with materials in equestion and incubated for two different periods three and seven days. They were assigned as group one and group two 10 µg Levofloxacin, group three and group four 20µg levofloxacin, group five and group six considered positive control 0.05 µg Mitomycin-C, group seven and group eight (Phosphate Buffer Saline) considered negative control groups. All eggs from in-ovo experiments were subjected to cytogenetic tests, such as Mitotic Index, Replicative Index and Sister Chromatid exchange. Eighty fertilized eggs were handled with the same manner of in-ovo inoculation and used for calculation Hatchability index and weekly body weight. The results revealed significant (P
... Sode's research indicated that quinolone use might triple the risk of Achilles tendon rupture [7]. Recent studies showed that levofloxacin could trigger cytotoxic effects on anterior cruciate ligament and fibroblast-like synoviocytes of rabbits [2,8,9]. The mechanism of toxic effects of fluoroquinolones on tendon cells in vitro has been well defined [1]. ...
... Previous studies showed that when combined with IL-1b, ciprofloxacin could increase the expression of MMPs in human tendon cells after being incubated with ciprofloxacin at a concentration of 150 μM (50 μg/ml) for 48 h, but in the absence of IL-1b, ciprofloxacin caused no significant effects on the expression of certain MMPs, even at a high concentration [10,15]. In another study, levofloxacin was found to significantly increase the mRNA expression of MMP-3 and MMP-13 in a concentration-dependent manner, even at the low concentration of 14 μM without IL-1b [8], which was in line with the result in our study that levofloxacin showed similar cytotoxicity on RAF cells. These above-mentioned results seem to indicate that ACL (anterior cruciate ligament) cells and AF cells are more susceptible to cytotoxicity by fluoroquinolones than This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License tendon cells or that levofloxacin is more cytotoxic than ciprofloxacin. ...
Background
Fluoroquinolones are in wide clinical use as safe and effective antibiotics. Articular cartilage, tendons, and epiphyseal growth plates have been recognized as targets of fluoroquinolone-induced connective tissue toxicity. However, the effects of fluoroquinolones on annulus fibrosus (AF) cells are still unknown.
Material/Methods
The main objective of this study was to investigate the effects of levofloxacin, a typical fluoroquinolone antibiotic drug, on rat AF cells in vitro. Rat annulus fibrosus (RAF) cells were treated with levofloxacin at different concentrations (0, 10, 20, 30, 40, 60, 80, and 90 μg/ml) and were assessed to determine the possible cytotoxic effects of levofloxacin. Inverted phase-contrast microscopy was used to accomplish the morphological observation of apoptosis of treated cells. Western blot and real-time quantitative RT-PCR (qPCR) was used to explore the expression of active caspase-3 and MMP-3. Flow cytometry was used to measure the apoptotic incidences.
Results
Our study showed that levofloxacin, with concentrations at 30, 60, and 90 μg/ml, induced dose-dependent RAF cell apoptosis and higher expression of caspase-3 and MMP-3. More apoptotic cells were observed by inverted phase-contrast microscopy. Moreover, levofloxacin increased the activity of caspase-3, and it also reduced cell viability with different concentrations ranging from 10 to 80 μg/ml.
Conclusions
Our study results suggest that levofloxacin has cytotoxic effects on RAF cells, characterized by enhancing apoptosis and reducing cell viability, and indicate a potential toxic effect of fluoroquinolones on RAF cells.
... Levofloxacin hemihydrate (LEV hereafter) is a broad-spectrum antibiotic which is a third-generation fluroquinolone. It is the levo isomer of oflaxacin [28][29][30] soluble up to 25 mg/mL in water and having bitter taste [31]. According to the biopharmaceutical classification system, it has been classified as a class-I drug which has no severe solubility or bioavailability problems [32]. ...
To overcome the issue of multidrug resistant (MDR) microbes, the exploration of ways to improve the antimicrobial efficiency of existing antibiotics is one of the promising approaches. In search of synthons with higher efficiency, in current investigations, cocrystal and amorphous salt of levofloxacin hemihydrate (LEV) were developed with phthalimide (PTH) and caffeic acid (CFA). New materials were characterized with the help of FT-IR, Raman spectroscopy, powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Shifting, attenuation, appearance/disappearance and broadening of bands were observed in the FT-IR and Raman spectra of the materials as evidence of the required product. The PXRD diffraction pattern observed for LEV-PTH indicated cocrystal while halo diffractogram of LEV-CFA revealed amorphous nature. DSC/TG analysis confirmed the hydrated nature of the cocrystal/salt. The dissolution rate and antimicrobial activity against selected strains, K.pneumonia, E. coli and S. typhi of parent drug and the new material were compared. The zone of inhibition (ZI) observed for 5 µg LEV-PTH was 30.4 + 0.36 (K. pneumonia), 26.33 + 0.35 (E. coli) and 30.03 + 0.25 mm (S. typhi) while LEV-CFA salt (5 µg) against the same strains inhibited 33.96 ± 0.25, 31.66 ± 0.35 and 27.93 ± 0.40 mm, respectively. These novel formulations enhance the dissolution rate as well as antibacterial efficiency and are expected to be potent against MDR bacterial strains.
... Os antibióticos do tipo quinolonas se mostram como escolha por serem amplamente utilizados clinicamente devido à sua potente atividade antibacteriana, excelente penetração tecidual e alta biodisponibilidade1 6 . No entanto, foi relatado que quinolonas induzem efeitos adversos no sistema musculoesquelético, incluindo cartilagem articular, ligamentos e tendões 16,17 . ...
A osteomielite é considerada uma doença incomum em pacientes saudáveis e de difícil diagnóstico e tratamento. Estudos sugerem que patologias infecciosas periodontais e peri-implantares como gengivites, periodontites e peri-implantites atuam como fatores mais comuns, predisponentes para osteomielites dos maxilares. Osteomielites crônicas exigem tratamento com cobertura antibiótica e procedimentos cirúrgicos. O tratamento envolve avaliação, determinação da etiologia, terapia antimicrobiana, desbridamento da lesão, remoção dos sequestros ósseos e decorticação óssea associada ao emprego sistêmico de antimicrobianos, geralmente de amplo espectro. O presente trabalho tem como objetivo relatar dois casos clínicos de osteomielite crônica infantil, bem como realizar uma análise comparativa de casos clínicos já publicados em artigos científicos. Pôde-se concluir que a associação de características clínicas, exames histopatológicos e achados radiográficos podem reunir características comuns para diversos tipos de osteomielite. Portanto, devem culminar em fatores contribuintes para o diagnóstico final. Em ambos os casos relatados, o tratamento foi eficaz utilizando terapia medicamentosa com o uso de anti-inflamatórios e antibióticos aliados a tratamento cirúrgico que consistiu em desbridamento da lesão. Ambos os pacientes foram acompanhados e proservados, não havendo recidiva. Descritores: Osteomielite; Antibacterianos; Patologia Bucal; Procedimentos Cirúrgicos Bucais.ReferênciasHupp JR, Ellis E, Tucker MR. Cirurgia oral e maxilofacial contemporânea. Rio de Janeiro: Elsevier; 2011.Lew DP, Waldvogel FA. Osteomyelitis. Lancet. 2004;364(9431):369-79.Baltieri BR, Gabrielli MAC, Gabrielli MFR, Pereira Filho VA, Lopes FS, Leite VA. Osteomielite em mandíbula de criança. Rev Odontol Unesp. 2014;43(N Especial):262.Gaetti Júnior E, Gaetti Jardim EC, Faverani LP, Landucci KC, Landucci LF. Osteomielite crônica dos maxilares: aspectos clínicos, terapêuticos e microbiológicos. Salusvita. 2008;27(1):125-39.Carek PJ, Dickerson LM, Sack JL . Diagnosis and management of osteomyelitis. Am Fam Physician. 2001;63(12):2413-20.6. Miloro M, Ghali GE, Larse PE, Waite PD. Princípios de cirurgia bucomaxilofacial de Peterson. 2ed. São Paulo: Santos; 2008.Neville BW, Damm DD, Allen CM, Bouquot JE. Patologia oral e maxilofacial. Rio de Janeiro: Elsevier; 2011.Watanabe T, Ono H, Morimoto Y, Otsuki Y, Shirai M, Endoh A et al. Skull involvement in a pediatric case of chronic recurrent multifocal osteomyelitis. Nagoya J Med Sci. 2015;77(3):493-500.Suei Y, Taguchi A, Tanimoto K. Diagnosis and classification of mandibular osteomyelitis. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2005;100(2):207-14.Masocatto DC, Oliveira MM, Mendonça JCG. Osteomielite crônica mandibular: relato de caso. Arch Health Invest.2017;6(2):48-52Ferraria N, Marques JG, Ramos F, Lopes G, Fonseca JG, Neves MC. Osteomielite crónica multifocal recorrente: série de 4 casos clínicos tratados com bifosfonatos. Acta Reumatol Port. 2014;39(1):38-45Paim LB, Liphaus BL, Rocha AC, Castellanos LZA, Silva CAA. Osteomielite crônica multifocal recorrente da mandíbula: relato de três casos. J Pediatr. 2003;79(5):467-70.Sousa MV, Malheiro R, Neves J, Varandas L, Conde M. Osteomielite crónica não bacteriana unifocal da mandíbula. Acta Reumatol Port. 2014:39;94-95Kadom N, Egloff A, Obeid G, Bandarkar A, Vezina G. Juvenile mandibular chronic osteomyelitis: multimodality imaging findings. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2011;111(3):e38-43.Theologie-Lygidakis N, Schoinohoriti O, Iatrou I. Surgical management of primary chronic osteomyelitis of the jaws in children: a prospective analysis of five cases and review of the literature. Oral Maxillofac Surg. 2011;15(1):41-50.Wang L, Wu Y, Tan Y, Fei X, Deng Y, Cao H et al. Cytotoxic effects of the quinolone levofloxacin on rabbit meniscus cells. J Appl Toxicol. 2014;34(8):870-77.Deng Y, Chen B, Qi Y, Magdalou J, Wang H, Chen L. The effects of levofloxacin on rabbit anterior cruciate ligament cells in vitro. Toxicol Appl Pharmacol. 2011;257(1):67-73.Obel G, Krogdahl A, Thygesen T, Godballe C. Juvenile mandibular chronic osteomyelitis: 3 cases and a literature review. J Oral Maxillofac Surg. 2013;71(2):305-9.
... in the Ames test, but significantly increased the number of cells containing structural aberration in CHL cells rather than structural aberrations.Tan et al. found that levofloxacin significantly reduced cell viability and hyaluronan level, while increasing apopitosis and active caspase-3 levels in rabbit fibroblast-like synoviocyte cells (FLS) and indicated that levofloxacin have cytotoxic effect on FLS cells. Deng et22 al. observed that levofloxacin increased apoptosis in rabbit anterior cruciate ligament cells (ACL) treated with levofloxacin but reduced the amount of extracellular matrix and they reported that levofloxacin have cytotoxic effect on these cells.Due to lack of knowledge about genotoxicity of levofloxacin in cultured human lymphocytes, in this study, possible genotoxic effects of levofloxacin were investigated by using in vitro SCE, CA, and MN tests. In this study, treament with different doses of levofloxacin(12.50, 25, 50, and 100 µg/ml) for 24 and 48 hours did not effect SCE12 frequency of treated cells in contrast to the study of Shimada in which levofloxacin increased SCE level dose dependently. ...
Background and Objectives: Levofloxacin, is a third generation quinolon antibiotic used in the the treatment of upper
respiratory tract, urinary tract, skin and soft tissue, bone-joint, eye and ear infections. In this study, possible genotoxic
effects of levofloxacin were analyzed by using sister chromatid exchanges (SCE), chromosome aberrations (CA) and micronucleus (MN) tests
in human peripheral lymphocytes.
Methods: Peripheral blood samples taken from two healthy women and two men were treated with four different concentrations of
levofloxacin (12,5, 25, 50 and 100 μg /ml) for 24 and 48 hours and SCE, CA, and MN levels of treated cells were examined. In order to analyze
the cytotoxic effect, mitotic index, proliferation index and nuclear division index in the treated cells were also determined. e obtained data
was compared with the control by using SPSS (17.0) software programme.
Results: Treatment with the different doses of levofloxacin for 24 and 48 h did not effect the SCE frequency, but highest levofloxacin dose (100
μg/ml) caused a significant increase in the CA level. Also, treatment of 25, 50, and 100 μg/ml levofloxacin significantly increased the MN level
as compared the control group. ere was no significant differences between the treated cells and control according to the proliferation index,
mitotic index, and nuclear division index. In conclusion, levofloxacin has genotoxic but not cytotoxic effect in human peripheral lymhocytes.
... Levofloxacin, the levo isomer of ofloxacin is a third generation fluoroquinolone which is used as a broad spectrum antibiotic for various Gram-positive and Gram-negative organisms (Deng et al. 2011;Drozak et al. 2008;Tasso et al. 2011). Levofloxacin, (S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido[1,2,3de]-1,4-benzoxazine-6-carboxylic acid hemihydrate is a slightly water soluble drug (25 mg/mL) with intense bitter taste (Koeppe et al. 2011). ...
The current investigation aimed to enhance the dissolution rate and mask the bitter taste of levofloxacin by developing pharmaceutical cocrystals using stearic acid and saccharin sodium as coformers. The developed cocrystals were characterized by Fourier transform infrared spectroscopy, which showed the formation of a regular carboxylic acid homosynthon in 1:1 ratio of levofloxacin-stearic acid and carboxylic acid- imide heterosynthon in 2:1 ratio of levofloxacin-saccharin sodium. The existence of the drug in a new crystalline form in the developed cocrystals was confirmed by solid state characterization. The dissolution studies of the developed cocrystals in simulated gastric fluid (pH 1.2) showed significant improvement of the drug dissolution rate (%min⁻¹) from L-ST1 (7.8 ± 0.1) and L-SA2 (7.2 ± 0.4) cocrystals compared to supplied levofloxacin (4.4 ± 0.3). The taste masking ability of L-ST1 and L-SA2 was determined by conducting dissolution studies at salivary pH 6.6 and the results showed a very low drug release of 6.6 ± 0.6% from L-ST1 compared to supplied levofloxacin (64.5 ± 1.5%) and L-SA2 (55.1 ± 1.5%) in 5 min. This study demonstrates that pharmaceutical cocrystals of levofloxacin with stearic acid at 1:1 ratio enhanced the dissolution rate and masked the bitter taste of levofloxacin whereas saccharin sodium has showed only improved dissolution.
... However, the related side effects of fluoroquinolone are not uncommon in the connective tissue toxicities: such as articular cartilages and epiphyseal growth plate pain [3,4], Sode showed that quinolone use might increase the risk of tendon rupture, principally described for the Achilles tendon [5]. There were literatures reporting that levofloxacin can induce apoptosis of rabbit anterior cruciate ligament cells [6] and fibroblast-like synoviocytes [7] through enhanced mRNA expression of MMPs. Corps et al. indicated that the ciprofloxacin, a kind of fluoroquinolones, significantly upregulating the mRNA expression of MMP-1, -3 and -13 in cultured human tenocytes [8,9]. ...
Levofloxacin was previously reported to induce apoptosis of rat annulus fibrosus (AF) cells by upregulating active caspase-3 and matrix metalloproteinase (MMP)-3 expression in vitro. However, the effects of levofloxacin on rat AF cells, as well as the related mechanism, have not been revealed completely. The purpose of this study was to further explore the changes in extracellular matrix and MMPs of rat AF cells based on levofloxacin-induced apoptosis. AF cells isolated from rat AF regions were cultured in monolayers and treated with levofloxacin in a dose- and time-dependent manner. To determine the cytotoxic effects of levofloxacin, inverted phase-contrast microscopy was used to perform morphological observation of apoptotic cells. The mRNA expression levels of MMP-2, -9 and -13 were quantified by reverse transcription and real-time quantitative polymerase chain reaction (RT-qPCR). Protein level of MMP-2 and MMP-13 were determined by western blot. The results showed that levofloxacin induced marked AF cell apoptosis, which was observed by inverted phase-contrast microscopy, and indicated by the increased expression of active caspase-3. Both RT-qPCR and western blot revealed that MMP-2 and MMP-13 expression were upregulated by levofloxacin treatment in a time- and dose-dependent manner. Moreover, cellular binding to type I collagen was found to be decreased by levofloxacin. In conclusion, the results above suggest that the possible cytotoxic effects of levofloxacin on AF cells in vitro may be attributed to the decreased cell binding to type I collagen and up-regulated expression of MMP-2 and MMP-13.
... 15 Tendon pain and degeneration have been associated with an increase in the normal turnover of matrix proteins. 2,18,33 It has been reported that FQs alter soft tissue structures and MMP expression in both in vitro [7][8][9][10]42,48 and in vivo models. 37,39 In agreement with these studies, our biochemical findings suggest that alterations in inflammatory-driven abnormal ECM remodeling may contribute to FQ-induced tendon damage. ...
Background:
Recent studies suggest that fluoroquinolone antibiotics predispose tendons to tendinopathy and/or rupture. However, no investigations on the reparative capacity of tendons exposed to fluoroquinolones have been conducted.
Hypothesis:
Fluoroquinolone-treated animals will have inferior biochemical, histological, and biomechanical properties at the healing tendon-bone enthesis compared with controls.
Study design:
Controlled laboratory study.
Methods:
Ninety-two rats underwent rotator cuff repair and were randomly assigned to 1 of 4 groups: (1) preoperative (Preop), whereby animals received fleroxacin for 1 week preoperatively; (2) pre- and postoperative (Pre/Postop), whereby animals received fleroxacin for 1 week preoperatively and for 2 weeks postoperatively; (3) postoperative (Postop), whereby animals received fleroxacin for 2 weeks postoperatively; and (4) control, whereby animals received vehicle for 1 week preoperatively and for 2 weeks postoperatively. Rats were euthanized at 2 weeks postoperatively for biochemical, histological, and biomechanical analysis. All data were expressed as mean ± standard error of the mean (SEM). Statistical comparisons were performed using either 1-way or 2-way ANOVA, with P < .05 considered significant.
Results:
Reverse transcriptase quantitative polymerase chain reaction (RTqPCR) analysis revealed a 30-fold increase in expression of matrix metalloproteinase (MMP)-3, a 7-fold increase in MMP-13, and a 4-fold increase in tissue inhibitor of metalloproteinases (TIMP)-1 in the Pre/Postop group compared with the other groups. The appearance of the healing enthesis in all treated animals was qualitatively different than that in controls. The tendons were friable and atrophic. All 3 treated groups showed significantly less fibrocartilage and poorly organized collagen at the healing enthesis compared with control animals. There was a significant difference in the mode of failure, with treated animals demonstrating an intrasubstance failure of the supraspinatus tendon during testing. In contrast, only 1 of 10 control samples failed within the tendon substance. The healing enthesis of the Pre/Postop group displayed significantly reduced ultimate load to failure compared with the Preop, Postop, and control groups. There was no significant difference in load to failure in the Preop group compared with the Postop group. Pre/Postop animals demonstrated significantly reduced cross-sectional area compared with the Postop and control groups. There was also a significant reduction in area between the Preop and control groups.
Conclusion:
In this preliminary study, fluoroquinolone treatment negatively influenced tendon healing.
Clinical relevance:
These findings indicate that there was an active but inadequate repair response that has potential clinical implications for patients who are exposed to fluoroquinolones before tendon repair surgery.
The study aimed to assess some embryonic reproductive parameters and histological effects stimulated by levaquin drug in administrated female rats before pregnancy, 8 female rats Rattus rattus with age average (90) days and weight average (230) gm, these animals were distributed into two groups and each of them contained 4 female rats, the first group was administrated with only distal water and treated as a control group, while the other group was treated with levaquin drug at a concentration of 650 mg / kg, the treatment of the females in the two groups continued for 75 days before pregnancy with single dose through the mouth by stomach tube ,then the treated female rats were married with 8 fertile adult male rats (Rattus rattus) and monitored until pregnancy occurred and after confirmation occurrence of the pregnancy, pregnant female animals were left and at 18 th day of pregnancy dissected, the numbers of embryos in two uterine horns, non-living ,absorbed and living embryos were counted and the histological changes of some organs (livers and kidneys) in pregnant female rats and their embryos were studied. The study results indicated that a significant elevation (p<0.05) in the numbers of non-living and absorbed embryos ,weights of body, liver and kidney of embryos ,whereas there was a significant reduction (p<0.05)in embryo numbers in two uterine horns and living embryos in treated group with levaquin drug when compared with control group , the histological results of this study showed different pathological changes in tissues of livers and kidneys of the embryos and pregnant female rats which were treated with levaquin drug before pregnancy compared with untreated pregnant group animals. Conclusion: It can be concluded from the results of this study the administration of levaquin drug of female rats before pregnancy stimulated embryonic and histological harmful effects in pregnant female rats and their embryos, so the drug may have a cumulative effect inside the body of pregnant females which affected subsequently the embryos during pregnancy.
Introduction:
The present systematic review investigates the biological and chemical mechanisms that affect the health and structure of tendons following the use of fluoroquinolones (FQs).
Sources of data:
A total of 12 articles were included, organized, and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.
Areas of agreement:
Five mechanisms were identified: arrest of proliferation through a decreased activity of cyclin B, CDK-1, CHK-1, and increased PK-1; decrease tenocytes migration through decreased phosphorylation of FAK; decrease type I collagen metabolism through increased MMP-2; chelate effect on ions that influence epigenetics and several enzymes; fluoroquinolones-induced ROS (radical oxygen species) production in mitochondria.
Areas of controversy:
There is no definite structure-damage relationship. The dose-effect relationship is unclear.
Growing points:
Knowing and defining the damage exerted by FQs plays a role in clinical practice, replacing FQs with other antibacterial drugs or using antioxidants to attenuate their pathological effects.
Areas timely for developing research:
Clinical and basic sciences studies for each FQs are necessary.
Abstract Levofloxacin, a fluoroquinolone, is a widely-used and effective antibiotic. However, various adverse side effects are associated with levofloxacin. The purpose of this study was to further explore the effects of levofloxacin on rat nucleus pulposus cells. Inverted phase-contrast microscopy, flow cytometry, and caspase-3 activity assays were used, and revealed that serum deprivation induced apoptosis, which was markedly increased by levofloxacin in a dose-dependent manner. Simultaneously, levofloxacin decreased cell binding to type II collagen. Thus, levofloxacin-induced apoptosis exhibits characteristics of anoikis, the process by which cell death is triggered by separation from the extracellular matrix, which contains type II collagen. Furthermore, real-time quantitative RT-PCR was used to further confirm that levofloxacin downregulates type II collagen expression in a dose-dependent manner. At last, western blot was used to find that levofloxacin increased the ratio of Bax/Bcl-2 and active caspase-3 in a dose-dependent manner. Levofloxacin therefore increases the effects of serum deprivation on anoikis by downregulating type II collagen in rat nucleus pulposus cells in vitro via Bax/Bcl-2/caspase-3 pathway. This research provides a novel insight into the mechanisms of levofloxacin-induced toxicity, and may potentially lead to a better understanding of the clinical effects of levofloxacin, especially in terms of intervertebral disc degeneration.
Levofloxacin has been reported to have cytotoxicity to chondrocytes in vitro. And 17β-estradiol has been widely studied for its protective effects against cell apoptosis. Based on apoptotic cell model induced by levofloxacin, the purpose of this study was to explore the mechanism by which 17β-estradiol protects rat nucleus pulposus cells from apoptosis. Inverted phase-contrast microscopy, flow cytometry, and caspase-3 activity assay were used to find that levofloxacin induced marked apoptosis, which was abolished by 17β-estradiol. Interestingly, estrogen receptor antagonist, ICI182780, and functional blocking antibody to α2β1 integrin, both prohibited the effect of 17β-estradiol. Simultaneously, levofloxacin decreased cellular binding ability to type II collagen, which was also reversed by 17β-estradiol. Furthermore, western blot and real-time quantitative PCR were used to find that integrin α2β1 was responsible for estrogen-dependent anti-apoptosis, which was time-response and dose-response effect. 17β-estradiol was proved for the first time to protect rat nucleus pulposus cells against levofloxacin-induced apoptosis by upregulating integrin α2β1 signal pathway.
The purpose of this study was to investigate the possibility that oxidative stress was involved in danofloxacin-induced toxicity in renal tubular cells epithelial cell line (LLC-PK1). Confluent LLC-PK1 cells were incubated with various concentrations of danofloxacin. The extent of oxidative damage was assessed by measuring the reactive oxygen species (ROS) level, lipid peroxidation, cell apoptosis and antioxidative enzyme activities. Danofloxacin induced a concentration-dependent increase in the ROS production, not even cytotoxic conditions. Similarly, danofloxacin caused an about 4-fold increase in the level of thiobartituric acid reactive substances at the concentration of 400 μM for 24 hr, but it did not induce cytotoxicity and apoptosis. Antioxidant enzymes activities, such as superoxide dismutase (SOD) and catalase (CAT), were increased after treatment with 100, 200 and 400 μM of danofloxacin for 24 hr. The activity of glutathione peroxidase (GPX) was significantly decreased in a concentration-dependent manner. In addition, ROS production, lipid peroxidation and GPX decline were inhibited by additional glutathione and N-acetyl cysteine. These data suggested that danofloxacin could not induce oxidative stress in LLC-PK1 cells at the concentration (≤400 μM) for 24 hr. The increase levels of ROS and lipid peroxidation could be partly abated by the increase activities of SOD and CAT. This article is protected by copyright. All rights reserved.
Quinolones have been reported to induce adverse effects on articular cartilage, tendons and ligaments. However, the effects of quinolones on menisci have not been revealed. The present study was to test the effects of levofloxacin on meniscus cells in vitro. Rabbit meniscus cells were administrated with different concentrations of levofloxacin (0, 14, 28, 56, 112 and 224 µm) for 24 or 48 h, and cell viability and apoptosis were measured. The mRNA expression levels of matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, tissue inhibitors of metalloproteinase (TIMP)-1, TIMP-3, Col1a1, Bcl-2, caspase-3 and inducible nitric oxide were analyzed by real-time polymerase chain reaction. Active caspase-3 was detected by immunocytochemical assay, while protein expression levels of MMP-3 and MMP-13 were measured by Western blotting assay. After treatment with levofloxacin for 48 h, cell viability was decreased from dose of 28 to 224 µm in a concentration-dependent manner. An increase of apoptotic cells was observed by flow cytometry. Active caspase-3 protein expression level was also increased. The mRNA level of Bcl-2 was decreased and levels of MMP-1, MMP-3 and MMP-13 in experimental groups were higher than those of controls. The protein levels of MMP-3 and MMP-13 were increased. Moreover, the mRNA levels of TIMP-3 and col1a1 were decreased. A dose-dependent increase of inducible nitric oxide mRNA expression level was also observed. Our results suggested the cytotoxic effects of levofloxacin on meniscus cells through induction of apoptosis and unbalanced MMPs/TIMPs expression. These side effects might result in meniscus extracellular matrix degradation and meniscal lesion. Thus, quinolones should be used cautiously on patients who perform athletic activities or undergo surgical meniscus repair. Copyright © 2013 John Wiley & Sons, Ltd.
It is widely accepted that tendon and cartilage are adversely affected with the toxic effects of quinolones. However, the effects of quinolones on synovium have not been deciphered completely. In this study, our main objective was to investigate the effects of levofloxacin, a typical quinolone antibiotic drug, on fibroblast-like synoviocytes (FLSs) in vitro. FLS of rabbits were treated with levofloxacin at different concentrations (0, 14, 28, 56, 112 and 224μM). The possible cytotoxic effects of levofloxacin on FLS were determined. Levofloxacin significantly reduced the cell viabilities, gene expression of hyaluronan synthase-2 (HAS-2), and the level of hyaluronan in FLS. Moreover, levofloxacin-induced concentration-dependent increases of apoptosis and active caspase-3 were determined in this study. Ultrastructural damages of FLS were observed by electron microscopy. The mRNA expression levels of matrix metalloproteinase (MMP)-3 and MMP-13 were increased in FLS treated with levofloxacin. In addition, levofloxacin played a role in suppressing the expression of interleukin (IL)-1 and IL-6. Our data suggest that the cytotoxic effects of levofloxacin on FLS were shown to be able to affect cell viability and HA synthesis capacity. The potential mechanisms of the cytotoxic effects may be attributed to the apoptosis and increased expression of MMPs.
Women are more susceptible to anterior cruciate ligament (ACL) injuries than men performing similar athletic activities. Because tissue remodeling may affect ligament strength, we assessed expression of tissue remodeling effector genes in the human ACL. Specifically, we surveyed ACL for RNAs encoding all known matrix metalloproteases (MMPs) and tissue inhibitors of metalloproteases (TIMPs) by reverse transcription/polymerase chain reaction (RT-PCR). These experiments revealed that mRNAs encoding nine of sixteen MMPs and all four TIMPs are present in the normal ACL. The nine expressed proteases were MMPs 1-3, 7, 9, 11, 14, and 17 (collagenase 1, gelatinase A, stromelysin 1, matrilysin, gelatinase B, stromelysin 3, and membrane types 1 and 4, respectively), and MMP-18. Genes for MMPs 8, 10, 12, 13, 15, and 16 appeared not to be expressed in ACL, as their mRNAs were not detected using RT-PCR conditions that did yield positive signals from other tissues (testis or bone). We conclude that numerous genes encoding tissue remodeling effector proteins are expressedin the human ACL.
We did not observe signs of chondrotoxicity in immature rats treated orally with garenoxacin (BMS-284756) at doses up to five
times 600 mg/kg of body weight or with ciprofloxacin, whereas ofloxacin induced typical cartilage lesions. The peak plasma
garenoxacin concentration was 25.5 mg/liter after administration of a dose of 600 mg/kg once daily for 5 days. Assuming that
this model is predictive of human risk, BMS-284756 and ciprofloxacin should be more suitable for pediatric use than ofloxacin.
Acute wounds normally heal in a very orderly and efficient manner characterized by four distinct, but overlapping phases: hemostasis, inflammation, proliferation and remodeling. Specific biological markers characterize healing of acute wounds. Likewise, unique biologic markers also characterize pathologic responses resulting in fibrosis and chronic non-healing ulcers. This review describes the major biological processes associated with both normal and pathologic healing. The normal healing response begins the moment the tissue is injured. As the blood components spill into the site of injury, the platelets come into contact with exposed collagen and other elements of the extracellular matrix. This contact triggers the platelets to release clotting factors as well as essential growth factors and cytokines such as platelet-derived growth factor (PDGF) and transforming growth factor beta (TGF-beta). Following hemostasis, the neutrophils then enter the wound site and begin the critical task of phagocytosis to remove foreign materials, bacteria and damaged tissue. As part of this inflammatory phase, the macrophages appear and continue the process of phagocytosis as well as releasing more PDGF and TGF beta. Once the wound site is cleaned out, fibroblasts migrate in to begin the proliferative phase and deposit new extracellular matrix. The new collagen matrix then becomes cross-linked and organized during the final remodeling phase. In order for this efficient and highly controlled repair process to take place, there are numerous cell-signaling events that are required. In pathologic conditions such as non-healing pressure ulcers, this efficient and orderly process is lost and the ulcers are locked into a state of chronic inflammation characterized by abundant neutrophil infiltration with associated reactive oxygen species and destructive enzymes. Healing proceeds only after the inflammation is controlled. On the opposite end of the spectrum, fibrosis is characterized by excessive matrix deposition and reduced remodeling. Often fibrotic lesions are associated with increased densities of mast cells. By understanding the functional relationships of these biological processes of normal compared to abnormal wound healing, hopefully new strategies can be designed to treat the pathological conditions.
Fluoroquinolone antibiotics may cause tendon pain and rupture. We reported previously that the fluoroquinolone ciprofloxacin potentiated interleukin (IL)-1beta-stimulated expression of matrix metalloproteinases (MMP)-3 and MMP-1 in human tendon-derived cells. We have now tested additional fluoroquinolones and investigated whether they have a similar effect on expression of MMP-13.
Tendon cells were incubated for two periods of 48 h with or without fluoroquinolones and IL-1beta. Total ribonucleic acid (RNA) was assayed for MMP messenger RNA by relative quantitative reverse transcriptase polymerase chain reaction, with normalization for glyceraldehyde-3-phosphate dehydrogenase mRNA. Samples of supernatant medium were assayed for MMP output by activity assays.
MMP-13 was expressed by tendon cells at lower levels than MMP-1, and was stimulated typically 10- to 100-fold by IL-1beta. Ciprofloxacin, norfloxacin and ofloxacin each reduced both basal and stimulated expression of MMP-13 mRNA. In contrast, ciprofloxacin and norfloxacin increased basal and IL-1beta-stimulated MMP-1 mRNA expression. Both the inhibition of MMP-13 and the potentiation of MMP-1 expression by fluoroquinolones were accompanied by corresponding changes in IL-1beta-stimulated MMP output. The non-fluorinated quinolone nalidixic acid had lesser or no effects.
Fluoroquinolones show contrasting effects on the expression of the two collagenases MMP-1 and MMP-13, indicating specific effects on MMP gene regulation.
Tendons and ligaments (T/L) are very similar fibrous tissues that respectively connect muscle to bone and bone to bone. They are comprised of fibroblasts that produce large amounts of extra-cellular matrix, resulting in a dense and hypocellular structure. The complex molecular organization of T/L, together with high water content, are responsible for their viscoelastic properties, hence insuring their mechanical function. We will first review recent work on tendon embryology and discuss ligament formation, which has been less documented. We will next summarize our current knowledge of T/L molecular architecture, alterations of which are a major cause for disease. We will finally focus on T/L repair after injury and on genetic diseases responsible for T/L defects.
Anterior cruciate ligament injury is determined by two variables: the ultimate failure load of the ligament and the mechanical load applied to the ligament. All factors that contribute to anterior cruciate ligament injury must do so by affecting one or both of these two basic variables. Some factors, such as sex hormones and tissue remodeling, have a multifaceted effect on the failure load of the anterior cruciate ligament and the magnitude of the load applied to it. The model also illustrates the potentially profound effects that sex hormones and tissue remodeling likely have on female susceptibility to anterior cruciate ligament injuries.
Tendons and ligaments are elastic collagenous tissues with similar composition and hierarchical structure, contributing to motion. Their strength is related to the number and size of the collagen fibrils. Collagen fibrils increase in size during development and in response to increased physical demands or training. Tendon disorders are commonly seen in clinical practice and give rise to significant morbidity. Treatment is difficult and patients often suffer from the symptoms for quite a long time. Despite remodelling, the biochemical and mechanical properties of healed tendon tissue never match those of intact tendon. The prerequisite for focussed treatment strategies in the future will be an improved understanding of the molecular events both in the embryo and contributing to regeneration in the adult organism. Novel approaches include the local delivery of growth factors, stem- and tendon-cell-derived therapy, the application of mechanical load and gene-therapeutic approaches based on vehicles encoding selected factors, or combinations of these. Important factors are proteins of the extracellular matrix like the metalloproteinases, growth factors like the bone morphogenetic proteins but also intracellular signalling mediator proteins, such as the Smads and transcription factors from the helix-loop-helix and other families. In this review, we focus specifically on such molecular approaches based on mesenchymal stem cells.
To establish medical use of tissue engineering technology for ligament and tendon injuries, a scaffold was developed which has sufficient ability for cell growth, cell differentiation, and mechanical properties. The scaffold made from chitosan and 0.1 per cent hyaluronic acid has adequate biodegradability and biocompatibility. An animal experiment showed that the scaffold has less toxicity and less inflammation induction. Furthermore, in-vivo animal experiments showed that the mechanical properties of the engineered ligament or tendon had the possibility to stabilize the joint. It was shown that newly developed hybrid-polymer fibre scaffold has feasibility for joint tissue engineering.
Tissue inhibitors of matrix metalloproteinases (TIMPs) are a family of natural inhibitors that control the activity of matrix metalloproteinases (MMPs) in the extracellular matrix (ECM). Four members of this family have been so far characterized in a variety of species. These inhibitors share a similar structural feature characterized by the presence of 12 cysteine residues involved in disulfide bonds and a similar function by their ability to form inhibitory complexes with MMPs. The role of TIMPs in cancer has been the subject of conflicting reports with an antitumor activity reported by some investigators and a growth stimulation activity reported by others. Here we will discuss a series of data obtained in our laboratory supporting a role of TIMPs not only as inhibitors of invasion but also as regulators of cell growth. Using placental development as an example of a regulated invasive process, we have observed that the levels of TIMP-2 and TIMP-3 steadily increase between day 14.5 and 17.5 post-coitus. TIMPs are selectively expressed by spongiotrophoblastic cells that separate the labyrinthine zone, rich in fetal blood vessels and maternal blood sinuses, from the zone of giant cells forming the border between fetal and maternal tissues. TIMPs are also potent inhibitors of tumor growth in vivo. In melanoma cells, we have previously reported that over-expression of TIMP-2 inhibits the growth of tumors implanted in the skin of scid mice. This growth inhibition seems independent of angiogenesis but dependent on the collagen matrix. We observed that in the presence of fibrillar type I collagen, melanoma cells undergo a growth arrest at the G1 to S interphase transition of the cell cycle. This arrest is specific to the fibrillar structure of collagen because it is not observed in the presence of non-fibrillar collagen or other ECM components. It is associated with a specific upregulation of the cyclin inhibitor p27KIPI. The data therefore indicate that anchorage independent cells remain sensitive to growth regulatory signals that originate from the ECM and that these signals can specifically block tumor cell cycle. Thus our concept of the role of protease inhibitors such as TIMPs in cancer has substantially changed from an initial focus on inhibition of tumor invasion and metastasis to a broader focus on being molecules that-via their function as regulators of the ECM homeostasis-can control tumor cell growth.
Ciprofloxacin-induced tendinopathy and tendon rupture have been previously described, principally affecting the Achilles tendon. This study was designed to investigate the effect of ciprofloxacin on expressions of matrix metalloproteinases (MMP)-2 and -9, tissue inhibitors of metalloproteinase (TIMP)-1 and -2 as well as type I collagen in tendon cells. Tendon cells intrinsic to rat Achilles tendon were treated with ciprofloxacin and then underwent MTT (tetrazolium) assay. Real-time reverse-transcription polymerase chain reaction (RT-PCR) and Western blot analysis were used, respectively, to evaluate the gene and protein expressions of type I collagen, and MMP-2. Gelatin zymography was used to evaluate the enzymatic activities of MMP-2 and -9. Reverse zymography was used to evaluate TIMP-1 and -2. Immunohistochemical staining for MMP-2 in ciprofloxacin-treated tendon explants was performed. Collagen degradation was evaluated by incubation of conditioned medium with collagen. The results revealed that ciprofloxacin up-regulated the expression of MMP-2 in tendon cells at the mRNA and protein levels. Immunohistochemistry also confirmed the increased expressions of MMP-2 in ciprofloxacin-treated tendon explants. The enzymatic activity of MMP-2 was up-regulated whereas that of MMP-9, TIMP-1 or TIMP-2 was unchanged. The amount of secreted type I collagen in the conditioned medium decreased and type I collagen was degraded after ciprofloxacin treatment. In conclusion, ciprofloxacin up-regulates the expressions of MMP-2 in tendon cells and thus degraded type I collagen. These findings suggest a possible mechanism of ciprofloxacin-associated tendinopathy.
We examined the effects of the quinolone antibacterial agents pefloxacin (PFLX) and ofloxacin (OFLX) on the Achilles tendon of Sprague-Dawley rats. A single oral administration of PFLX 300 and 900 mg/kg or OFLX 900 mg/kg induced edema with mononuclear cell infiltration mainly in the inner sheath of the inner Achilles tendon just proximal to the tuber calcanei in rats killed on the next day. Cell infiltration was also seen in the adjacent synovial membrane and joint space. With progression of severity, the lesions extended to the surface tendon tissue, wherein irregularly arranged collagen bundles were detached from each other and nuclei of fibroblasts were pyknotic and fragmented. After 2-wk repeated administration, these lesions were replaced by fibrotic foci with regenerated tendon fibroblasts, and the incidence and severity were reduced in the OFLX but not PFLX groups. Coadministration of cyclosporin A with OFLX 300 mg/kg induced these lesions despite the fact that neither induced lesions alone. The tendon lesions were induced in juvenile rats (4 wk of age) but not in young adults (12 wk). The articular cartilage of juvenile rats showed focal degeneration and/or cavitation in the tarsal joints after a single and 2-wk administration of PFLX or OFLX. Hydrocortisone slightly increased the incidence of OFLX-induced lesions in both the tendon and cartilage after a 2-wk administration. The occurrence of the tendon lesions is different from that of the Achilles tendon disorders reported in older humans, but they are thought to be a useful model for them.
Achilles tendon pain or rupture after fluoroquionolone treatment has been described as an uncommon adverse effect. We report two patients with ciprofloxacin-associated Achilles tendon disease, one with histopathological examination. Microscopic evaluation showed irregular collagen fiber arrangement, hypercellularity, and increased interfibrillar glycosaminoglycans. These pathological features are also seen in tendon overuse injuries in athletes.
Tendinitis and tendon rupture complicating fluoroquinolone therapy have been reported recently, especially affecting men over 60 years. These new quinolones are more potent antimicrobial agents than older nonfluorinated compounds like nalidixic acid. We compared the effects of one quinolone (nalidixic acid) and two fluoroquinolones (norfloxacin and pefloxacin) on cultured rabbit Achilles tendon cells. First, we examined their effects on cell viability, mitochondrial succinate dehydrogenase and global activity, mitochondrial activity using microtitration methods. Pefloxacin and norfloxacin were more cytotoxic than nalidixic acid according to IC50 values. These results confirm that mitochondria represent a biological target of fluoroquinolones. Moreover, the extracellular matrix was studied by molecular hybridization. After a 72 h treatment, the level of type I collagen transcripts was not modified with any of the three antimicrobial agents, whereas mRNA encoding decorin was decreased with 10(-4) mol/L pefloxacin only. The decrease of transcripts encoding decorin suggests that this matrix component is another target of pefloxacin and modification of decorin seems to be an early event (before mitochondrion alteration) which may contribute to the explanation of tendon rupture.
We have sought to create, for the first time in a single comprehensive review, a modern synthesis of opinion on the cell, developmental, and molecular biology of tendons, ligaments, and their associated structures (tendon sheaths, vinculi, and retinacula). Particular attention has been paid to highlighting new data on the early development of tendons, the signaling molecules involved in their patterning, and the diversity of specialized regions (entheses, wrap-around regions, and myotendinous junctions) that characterize fully formed tendons and ligaments. We have emphasized the complexities of adult tendon and ligament cell shape and related these to their early development. The importance of gap junctions in allowing cell communication throughout an extensive extracellular matrix (ECM) has also been highlighted, particularly in relation to understanding how tendon and ligament cells respond to changes in mechanical load. Finally, we have considered the influence of growth factors and related molecules on cell proliferation and ECM synthesis.
The pathologic mechanisms underlying fluoroquinolone-induced tendinopathy are poorly understood. The observed incidence of tendinitis and tendon rupture in patients treated with ciprofloxacin hydrochloride suggests that the fluoroquinolone antibiotics alter tendon fibroblast metabolism. The purpose of this study was to examine the effect of ciprofloxacin on fibroblast metabolism in vitro. Canine Achilles tendon, paratenon, and shoulder capsule specimens were maintained in culture with ciprofloxacin (5, 10, or 50 microg/ml). Fibroblast proliferation, collagen synthesis, proteoglycan synthesis, and matrix-degrading activity were analyzed. Incubation of Achilles tendon, Achilles paratenon, and shoulder capsule fibroblasts with ciprofloxacin resulted in a statistically significant 66% to 68% decrease in cell proliferation compared with control cells at day 3 in culture. Ciprofloxacin caused a statistically significant 36% to 48% decrease in collagen synthesis compared with controls in all fibroblast cultures. Ciprofloxacin caused a statistically significant 14% to 60% decrease in proteoglycan synthesis in all fibroblast cell lines. Compared with unstimulated control fibroblasts, culture media from Achilles tendon, paratenon, and shoulder capsule cells that were exposed to ciprofloxacin demonstrated statistically significant increases in matrix-degrading proteolytic activity after 72 hours in culture. This study demonstrates that ciprofloxacin stimulates matrix-degrading protease activity from fibroblasts and that it exerts an inhibitory effect on fibroblast metabolism. The increase in protease activity and the inhibition of both cell proliferation and the synthesis of matrix ground substance may contribute to the clinically described tendinopathies associated with ciprofloxacin therapy.
Matrix metalloproteinases (MMP) are a family of structurally related proteinases most widely recognized for their ability to degrade extracellular matrix, although recent investigations have demonstrated other biologic functions for these enzymes. MMP are typically not constitutively expressed, but are regulated by: (1) cytokines, growth factors, and cell-cell and cell-matrix interactions that control gene expression; (2) activation of their proenzyme form; and (3) the presence of MMP inhibitors [tissue inhibitors of metalloproteinases, (TIMP)]. MMP have important roles in normal processes including development, wound healing, mammary gland, and uterine involution, but are also involved in angiogenesis, tumor growth, and metastasis. Angiogenesis, characteristically defined as the establishment of new vessels from pre-existing vasculature, is required for biologic processes such as wound healing and pathologic processes such as arthritis, tumor growth, and metastasis. Blocking of MMP activity has been studied for potential therapeutic efficacy in controlling such pathologic processes. Synthetic MMP inhibitors, most notably the hydroxymates, have been engineered for this purpose and are presently in clinical trial. These inhibitors may have broad versus specific MMP inhibitory activity. As increased non-matrix degrading capabilities of MMP are recognized, however, i.e., cytokine activation, processing of proteins to molecules of distinct biologic function, it becomes less clear whether the nonselective inhibition of MMP activity for all pathologic processes involving MMP is appropriate. This review focuses upon the contribution of MMP to the process of tumor invasion and angiogenesis, and discusses the design and use of MMP inhibitors as therapeutic agents in these processes.
This review focuses on the most recent research findings on adverse reactions caused by quinolone antibiotics. Reactions of the gastrointestinal tract, the central nervous system (CNS) and the skin are the most often observed adverse effects. Occasionally major events such as phototoxicity, cardiotoxicity, arthropathy and tendinitis occur, leading to significant tolerability problems. Over the years, several structure-activity and side-effect relationships have been developed, in an effort to improve overall antimicrobial efficacy while reducing undesirable side-effects. In this article we review the toxicity of fluoroquinolones, including the newer derivatives such levofloxacin, sparfloxacin, graepafloxacin and the 7-azabicyclo derivatives, trovafloxacin and moxifloxacin. A special attention is given to new data on mechanistic aspects, particularly those regarding CNS effects. In recent years extensive in vivo and in vitro experiments have been performed in an attempt to explain the neurotoxic effects of quinolones sometimes observed under therapeutic conditions. However, the molecular target or receptor for such effects is still not exactly known. Several mechanisms are thought to be responsible. The involvement of gamma-aminobutyric acid (GABA) and excitatory amino acid (EAA) neurotransmission and the kinetics of quinolones distribution in brain tissue are discussed. In addition, quinolones may interact with other drugs--theophylline and nonsteroidal antiflammatory drugs (NSAID(s))--in producing CNS effects This article provides information about the different mechanisms responsible of quinolones interaction with NSAID(s), methylxanthines, warfarin and antiacids.
Quinolone therapy can be associated with tendon disorders (tendinitis, ruptures), but little is known about possible ultrastructural changes in tendons after exposure to these antimicrobials. We studied the Achilles tendons from fleroxacin-treated adult rats by electron microscopy. Wistar rats were treated orally with single oral doses of 0, 30, 100, 300 or 600 mg fleroxacin/kg body weight (n=6 per group). The animals were killed 4 weeks after treatment, Achilles tendon samples were collected and tangential sections were made from the distal part of the tendon. Subsequently, tendons were cut crosswise for preparation of ultrathin sections. Samples were fixed by using glutaraldehyde, osmium tetroxide, tannic acid and finally contrasted with uranyl acetate/lead citrate before they were examined by transmission electron microscopy. The rats did not show any general effects such as behavioural changes or body weight changes which could be attributed to the treatment. However, we were able to detect pathological changes even at the lowest dose level (30 mg/kg), which increased in incidence and severity with increasing doses. Tenocytes exhibited degenerative changes such as multiple vacuoles and large vesicles in the cytoplasm that resulted from swelling and dilatation of cell organelles (mitochondria, endoplasmic reticulum). The nucleus became dense and the chromatin had clumped to form rough plaques. The cells detached from the extracellular matrix. Other important findings were a general decrease of the fibril diameter and an increase in the distance between the collagenous fibrils. The finding that these rather low single doses of a fluoroquinolone induce ultrastructural changes in Achilles tendons from rats, which were not associated with clinical symptoms and which were still present 4 weeks after treatment, is of concern. Further toxicological as well as clinical studies are needed to characterize the conditions under which quinolone-induced tendon lesions develop.
With the recent introduction of agents such as gatifloxacin and moxifloxacin, the traditional gram-negative coverage of fluoroquinolones has been expanded to include specific gram-positive organisms. Clinical applications beyond genitourinary tract infections include upper and lower respiratory infections, gastrointestinal infections, gynecologic infections, sexually transmitted diseases, and some skin and soft tissue infections. Most quinolones have excellent oral bioavailability, with serum drug concentrations equivalent to intravenous administration. Quinolones have few adverse effects, most notably nausea, headache, dizziness, and confusion. Less common but more serious adverse events include prolongation of the corrected QT interval, phototoxicity, liver enzyme abnormalities, arthropathy, and cartilage and tendon abnormalities. The new fluoroquinolones are rarely first-line agents and should be employed judiciously. Inappropriate use of agents from this important class of antibiotics will likely worsen current problems with antibiotic resistance. Applications of fluoroquinolones in biologic warfare are also discussed.
Reactions of the gastrointestinal tract and the central nervous system are the most often observed adverse effects during therapy with fluoroquinolones. Pathogenesis of the neurotoxic effects of fluoroquinolones could be related to the activation of the NMDA receptor. Animal experiments as well as clinical experience show that the cardiotoxic potentials of sparfloxacin and grepafloxacin are higher than those of the other fluoroquinolones: they cause QT prolongation at rather low doses thus increasing the risk for severe arrhythmia (torsades de pointes). Phototoxicity has been described for all quinolones, but derivatives with a halogen atom at position 8 show the highest potential for such reactions (e.g. clinafloxacin). Chondrotoxicity of quinolones can affect the articular cartilage and the epiphyseal growth plate in immature animals; the use of these drugs in pediatrics should be restricted to carefully selected indications (such as the use of ciprofloxacin in cystic fibrosis). Tendinitis and tendon ruptures can also be induced by quinolones. Overall, quinolones are as well tolerated as most other anti-microbial agents. However, their specific toxic potentials have to be considered when they are chosen for treatment of bacterial infections.
Functional outcomes of anterior cruciate ligament (ACL) injury are generally poorer than those of medial collateral ligament (MCL) tears. Following ligament damage, all phases of ligament healing require an adequate blood supply. We hypothesized that the differences in healing properties of the ACL and MCL would reflect their vascular responses to joint injury. This paper examines the long-term changes in blood flow and vascular volume of rabbit knee ligaments after direct injury, and under conditions of chronic joint instability induced by section of the posterior cruciate ligament (PCL). Standardized injuries were surgically induced in adult rabbit knee ligaments: partial MCL transection, partial ACL transection, or complete PCL transection (joint instability). Sixteen weeks later the blood flow and vascular volume of the ACL and MCL were measured and compared to control and sham-operated animals. Direct ligament injury induced significant increases in standardized blood flow and vascular volume of both ACL and MCL after 16 weeks; however, the vascular volume of the ACL was not higher than the control levels in the MCL. We conclude that direct injury to both the anterior cruciate and MCLs induces long-term physiological responses. Joint laxity is a common sequel to PCL injury. Chronic joint laxity failed to induce adaptive vascular responses in the ACL, while the MCL shows significant amplification of blood supply. Although both MCL and ACL showed increased weight after PCL transection, the lack of a long-term vascular response in the ACL may be a major factor in its the diminished healing potential.
To determine whether the fluoroquinolone antibiotic ciprofloxacin, which can cause tendon pain and rupture in a proportion of treated patients, affects the expression of matrix metalloproteinases (MMPs) in human tendon-derived cells in culture.
Cell cultures were derived from 6 separate tendon explants, and were incubated in 6-well culture plates for 2 periods of 48 hours each, with ciprofloxacin (or DMSO in controls) and interleukin-1beta (IL-1beta), alone and in combination. Samples of supernatant medium from the second 48-hour incubation were assayed for MMPs 1, 2, and 3 by Western blotting. RNA was extracted from the cells and assayed for MMP messenger RNA (mRNA) by semiquantitative reverse transcription-polymerase chain reaction, with normalization for GAPDH mRNA.
Unstimulated tendon cells expressed low or undetectable levels of MMP-1 and MMP-3, and substantial levels of MMP-2. IL-1beta induced a substantial output of both MMP-1 and MMP-3 into cell supernatants, reflecting increases (typically 100-fold) in MMP mRNA, but had only minor effects on MMP-2 expression. Ciprofloxacin had no detectable effect on MMP output in unstimulated cells. Preincubation with ciprofloxacin potentiated IL-1beta-stimulated MMP-3 output, reflecting a similar effect on MMP-3 mRNA expression. Ciprofloxacin also potentiated IL-1beta-stimulated MMP-1 mRNA expression, but did not potentiate the output of MMP-1, and had no significant effects on MMP-2 mRNA expression or output.
Ciprofloxacin can selectively enhance MMP expression in tendon-derived cells. Such effects might compromise tendon microstructure and integrity.
The aim of this study was to investigate the involvement of apoptosis (programmed cell death) in the pathogenesis of rotator cuff disorders. The edges of torn supraspinatus rotator cuff tendons were collected from patients with rotator cuff tear (n = 25). Samples of the intra-articular portion of subscapularis tendons were collected from patients without rotator cuff tear as control (n = 6). To minimize individual variance, we also collected six pairs of supraspinatus tendon and subscapularis tendon from six patients with rotator cuff tears. Apoptosis was detected by in situ DNA end labelling assay and DNA laddering assay. Immunohistochemical staining was performed to identify cells undergoing apoptosis. Control subscapularis tendon had normal morphology. Tendon from torn supraspinatus rotator cuff showed significant mucoid degeneration. Within the areas of degeneration, there were large numbers of apoptotic cells. The percentage of apoptotic cells in the degenerative rotator cuff (34%) was significantly higher than that in controls (13%) (p < 0.001). The excessive apoptosis detected in degenerative rotator cuff tissue was confirmed by DNA laddering assays. This is the first report of excessive apoptosis in degenerating rotator cuff tendon. Cells undergoing apoptosis in rotator cuff were mainly fibroblast-like cells. These finding indicate that apoptosis may play an important role in the pathogenesis of rotator cuff degeneration.
Thirty patients had anterior cruciate ligament reconstruction for ongoing instability. Two groups were defined according to gross morphologic features identified during reconstruction: anterior cruciate ligament disruptions with scars attached to a structure in the joint and disruptions without reattachments. Reverse transcription polymerase chain reaction for a subset of extracellular matrix molecules, proteinases, and proteinase inhibitors was done on samples of scarred anterior cruciate ligament tissue removed during reconstructive surgery. Results of the nonattached scar group showed significantly increased mRNA levels for Type I collagen, and an increased Type I to Type III collagen ratio compared with that for the attached scar group. In the first year after injury, decorin mRNA levels in the nonattached scar group also were significantly higher than in the attached scar group. Biglycan mRNA levels in the nonattached scar group correlated closely with Type I collagen mRNA levels. These results suggest differences in cellular expression in torn anterior cruciate ligaments that attach to structures in the joint versus those which do not. Although the molecular mechanisms responsible for these differences have not been delineated, different molecular signals may influence the gross morphologic features of anterior cruciate ligament disruptions or alternatively, differing gross morphologic features may be subject to different mechanical loads leading to altered molecular expression. However, the finding of endogenous cellular activity in injured anterior cruciate ligaments raises the possibility that this activity may be enhanced to improve outcomes.
We present a rare case of spontaneous bilateral Achilles tendon rupture induced by levofloxacin, one of the fluoroquinolone antibiotics. A 76-year-old man was diagnosed with acute appendicitis and was commenced on oral levofloxacin 300 mg/day for 2 weeks. Seven days afterward he developed pain in both Achilles tendons, and at 14 days he developed swelling in the tendons. Four days later he felt a sharp, painful snap in both Achilles tendons while changing trousers. Both Achilles tendons ruptured completely at the mid-portion. There was no obvious underlying disease or pathophysiological factor causing fragility of his Achilles tendons. Despite the relatively large volume of case-based evidence, the pathophysiology of fluoroquinolone-induced tendinitis and tendon rupture is unclear. When tendinitis develops during fluoroquinolone therapy, the physician should consider the possible association between the fluoroquinolone and tendon rupture.
Antimicrobial therapy with fluoroquinolones can be associated with tendinitis and other tendon disorders as an adverse reaction associated with this class of antimicrobials. Here we investigated aspects of the mechanism of quinolone-induced tendotoxicity in human tenocytes focussing mainly on the question whether fluoroquinolones may induce apoptosis. Monolayers of human tenocytes were incubated with ciprofloxacin or levofloxacin at different concentrations (0, 3, 10, 30 and 100mg/L medium) for up to 4 days. Ultrastructural changes were studied by electron microscopy, and alterations in synthesis of specific proteins were determined using immunoblotting. At concentrations, which are achievable during quinolone therapy, 3mg ciprofloxacin/L medium significantly decreased type I collagen; similar changes were observed with 3mg ciprofloxacin or 10mg levofloxacin/L medium for the beta(1)- integrin receptors. Effects were intensified at higher concentrations and longer incubation periods. Cytoskeletal and signalling proteins, such as activated shc or erk 1/2, were significantly reduced by both fluoroquinolones already at 3mg/L. Furthermore, time- and concentration-dependent increases of matrix metalloproteinases as well as of the apoptosis marker activated caspase-3 were found. Apoptotic changes were confirmed by electron microscopy: both fluoroquinolones caused typical alterations like condensed material in the nucleus, swollen cell organelles, apoptotic bodies and bleb formation at the cell membrane. Our results provide evidence that besides changes in receptor and signalling proteins apoptosis has to be considered as a final event in the pathogenesis of fluoroquinolone-induced tendopathies.
To describe a case of levofloxacin-induced partial Achilles tendon rupture; this occurred in the presence of known risk factors and acute renal failure.
A 79-year-old white man received levofloxacin for presumed pneumonia, developed acute renal failure in the setting of dehydration, and began having ankle pain on the 12th day of admission. Levofloxacin was discontinued, and magnetic resonance imaging revealed a 6-cm partial tear and degenerative changes.
The Naranjo probability scale indicates a possible association between levofloxacin and tendon rupture because the event occurred in the setting of known risk factors such as steroid use, renal failure, older age, and male gender.
Levofloxacin, like other fluoroquinolones, may cause Achilles tendon rupture, and this may be particularly likely with known risk factors.
To critically evaluate a possible increased anticoagulant response during concomitant warfarin and fluoroquinolone therapy.
A literature search was conducted using PubMed, International Pharmaceutical Abstracts, and MEDLINE, from inception to January 2008, combining the term warfarin individually with ciprofloxacin, levofloxacin, and moxifloxacin. These 3 quinolones were selected based on their commercial availability and use in the US.
All publication types including human participants and published in English were eligible for review. Reports were selected based on the use of typical treatment courses of fluoroquinolones during concomitant warfarin therapy and the reporting of prothrombin time (PT) or international normalized ratio (INR).
Twenty-two publications were evaluated including 16 case reports or case series, 2 retrospective cohort studies, and 4 prospective studies, which included 2 placebo-controlled investigations. Identified reports covered a wide range of patient ages with multiple comorbidities. Changes in PT and INR values were considerably variable and inconsistent during concomitant warfarin and fluoroquinolone therapy. Results from the 6 structured reports demonstrated mean increases in PT and INR values that were clinically insignificant. However, some patients experienced significant increases above the desired therapeutic range. Increased anticoagulation was typically observed within the first week of concomitant fluoroquinolone therapy. Bleeding complications during times of increased anticoagulation were not always observed, but did result in death for 2 patients.
Published data show no consistent increase in anticoagulant effects during concomitant warfarin and 3 commonly prescribed fluoroquinolones. Therefore, more frequent monitoring during concomitant therapy would be prudent.
The drastic difference in healing capacity between the anterior cruciate ligament and the medial collateral ligament is still largely unexplained. Few studies have compared the profiles of messenger ribonucleic acid expression for healing-associated molecules in ligaments during the course of healing.
Injury responses of the injured anterior cruciate ligament and medial collateral ligament are characterized by very different profiles of angiogenesis-promoting and repair-associated gene expression during the healing process.
Controlled laboratory study.
Reverse-transcriptase polymerase chain reaction was used to assay expression of messenger ribonucleic acid for 11 healing- and angiogenesis-associated molecules at 3 days and 2, 6, and 16 weeks after anterior cruciate ligament or medial collateral ligament injury in adult female New Zealand White rabbits.
Marked differences were found in the postinjury changes in messenger ribonucleic acid levels in the anterior cruciate ligament compared to the medial collateral ligament. Notably, messenger ribonucleic acid levels for the important repair-associated growth factor transforming growth factor-beta1 did not increase in injured anterior cruciate ligament at any time point. Similarly, unlike the injured medial collateral ligament, no statistically significant increases in messenger ribonucleic acid levels for the important scar matrix protein collagen III were detected in injured anterior cruciate ligament. In contrast, matrix metalloproteinase messenger ribonucleic acid levels were markedly elevated in injured anterior cruciate ligament but only modestly increased in medial collateral ligament.
The results suggest that injury leads to an antifibrotic, catabolic response in the rabbit anterior cruciate ligament, possibly to prevent fibrosis and diminish the risk for loss of joint motion.
The development of effective biologically based treatments for anterior cruciate ligament injuries will need to incorporate strategies to deal with the significant differences in the molecular responses to injury of these tissues.
To investigate the effect of ciprofloxacin on the proliferation and cell cycle progression of tendon cells, and to explore the potential molecular mechanism of ciprofloxacin-associated tendinopathy by analyzing the expression of cell cycle-related cyclin and cyclin-dependent kinase (CDK).
Rat Achilles tendon cells were treated with ciprofloxacin and then assessed by MTT assay, flow cytometric analysis, and fluorescence confocal microscopy. Levels of messenger RNA (mRNA) for CDK-1 and cyclin B were determined by reverse transcriptase-polymerase chain reaction. Protein expression of CDK-1, cyclin B, checkpoint kinase 1 (CHK-1), and polo-like kinase 1 (PLK-1) was determined by Western blot analysis.
Ciprofloxacin inhibited tendon cell proliferation and caused cell cycle arrest at the G2/M phase. Confocal microscopy revealed that chromosomes in ciprofloxacin-treated cells neither properly aligned along the equatorial planes nor segregated successfully during metaphase. Mitotic arrest, misaligned chromosomes, and poor bipolar spindle formation were observed in ciprofloxacin-treated cells. CDK-1 and cyclin B protein and mRNA were both down-regulated. CHK-1 protein expression was also suppressed, but PLK-1 protein expression was up-regulated by ciprofloxacin.
Our findings suggest a possible mechanism of ciprofloxacin-associated tendinopathy. Down-regulation of CHK-1 and up-regulation of PLK-1 may account for mitotic arrest observed in ciprofloxacin-treated cells.
The effect of ciprofloxacin on tendon, paratenon, and capsular fibroblast metabolism
- Williams