Immunomodulatory action of levofloxacin on cytokine production by human peripheral blood mononuclear cells

Neurodegeneration, Mitochondria, and Antibiotics

Neurodegenerative diseases are characterized by the progressive loss of neurons, synapses, dendrites, and myelin in the central and/or peripheral nervous system. Actual therapeutic options for patients are scarce and merely palliative. Although they affect millions of patients worldwide, the molecular mechanisms underlying these conditions remain unclear. Mitochondrial dysfunction is generally found in neurodegenerative diseases and is believed to be involved in the pathomechanisms of these disorders. Therefore, therapies aiming to improve mitochondrial function are promising approaches for neurodegeneration. Although mitochondrial-targeted treatments are limited, new research findings have unraveled the therapeutic potential of several groups of antibiotics. These drugs possess pleiotropic effects beyond their anti-microbial activity, such as anti-inflammatory or mitochondrial enhancer function. In this review, we will discuss the controversial use of antibiotics as potential therapies in neurodegenerative diseases.

Levofloxacin might be safe to use for OSCC patients

Oral squamous cell carcinoma patients are exhausted against the powerful chemotherapies, radiotherapies after the surgery, and their immune system is devastated during the process and antibiotic usage become inescapable. Although prescribing an antibiotic might be fraught for such as drug interaction and undesirable proliferation danger, studies still look for the new ideas such as antibiotic combinations that might be safe to use. The antiproliferative and apoptotic outcomes of levofloxacin with cisplatin combination as well as their single usage were examined with WST-1, Caspase-3/BCA and Annexin V methods on SCC-15 cells and a healthy cell line (MRC-5). 24 h treatment of 50 mM single levofloxacin, 50 mM single cisplatin and 50 mM levofloxacin-cisplatin combination resulted in viability rates of SCC-15 cells as 90%, 67% and 80.8%, respectively. Caspase-3 enzyme activity was enhanced 0.92-fold for single levofloxacin, 13.05-fold for single cisplatin and 9.73-fold for the combination of levofloxacin-cisplatin, the total apoptotic activity of single levofloxacin, single cisplatin and levofloxacin-cisplatin combination were observed as 4.88%, 21.14%, 16.21%, respectively on SCC-15. The apoptotic effect of cisplatin on MRC-5 has been shown to be suppressed when combined with levofloxacin. Considering the cell viability, caspase-3, and apoptotic activity results, it's conclude that the levofloxacin-cisplatin combination was also effective compared to the only cisplatin treatment on OSCC cells. The combination has shown less toxicity for healthy cells than single cisplatin treatment. Therefore, our apoptotic findings suggest that the different dosage combinations are necessary to understand the interaction for the treatment of tongue squamous cell carcinoma.

A Review of Immunomodulatory Effects of Fluoroquinolones

Past researches indicate that some types of antibiotics, apart from their antimicrobial effects, have some other important effects which indirectly are exerted by modulating and regulating the immune system's mediators. Among the compounds with antimicrobial effects, fluoroquinolones (FQs) are known as synthetic antibiotics, which exhibit the property of decomposing of DNA and prevent bacterial growth by inactivating the enzymes involved in DNA twisting, including topoisomerase II (DNA gyrase) and IV. Interestingly, immune responses are indirectly modulated by FQs through suppressing pro-inflammatory cytokines, such as interleukin 1 (IL-1), IL-6, tumor necrosis factor-alpha (TNF-α), and super-inducing IL-2, which tend to increase both the growth and activity of T and B lymphocytes. In addition, they affect the development of immune responses by influencing of expression of other cytokines and mediators. This study aims to review past research on the immunomodulatory effects of FQs on the expression of cytokines, especially IL-2 and to discuss controversial investigations.

Sustainable waste management and recycling of Zn–Al layered double hydroxide after adsorption of levofloxacin as a safe anti-inflammatory nanomaterial

Inorganic nano-layered double hydroxide (LDH) materials are used in the catalytic field, and have demonstrated great applicability in the pharmacological fields. In the current study, we report Zn–Al LDH as an adsorbent for levofloxacin (levo). The physical and chemical properties of the prepared material before and after adsorption were monitored using X-ray diffraction, Fourier-transform infrared (FT-IR) spectroscopic analysis, energy dispersive X-ray spectroscopy (EDX), Brunauer–Emmett–Teller (BET) surface area measurements, high-resolution transmission electron microscopy (HRTEM), and field emission scanning electron microscopy (FESEM). Density functional theory (DFT) calculations for levo and its protonated species were studied at the B3LYP/6-311G (d,p) level of theory. The removal percentage of levo was 73.5%. The adsorption isotherm was investigated using nine different models at pH 9, where the obtained correlation coefficients (R²) using the Redlich–Peterson and Toth models were 0.977. The thermodynamic parameters ΔS°, ΔG° and ΔH° were estimated and discussed in detail. Also, to support the adsorption research field, the applicability of the formed waste after the adsorption of levo onto Zn–Al LDH was investigated for medical purposes. The toxicity of levo in both normal and nanocomposite form was studied. Neither toxicological symptoms nor harmless effects were exhibited throughout the in vivo study. The oral anti-inflammatory activity, tested using 6% formalin to produce edema in the footpad, was manifested as a significant increase of 37% in the anti-inflammatory effect of the Zn–Al LDH/levo nanocomposite compared to levo in its normal form.

Zn-Al LDH was synthesized using the co-precipitation method, characterized and used as an efficient adsorbent for the removal of levofloxacin. The safety and toxicity of the administered Zn-AL LDH/levo as a safe anti-inflammatory material.

Ciprofloxacin and levofloxacin attenuate microglia inflammatory response via TLR4/NF-kB pathway

BACKGROUND

Neuroinflammation is the response of the central nervous system to events that interfere with tissue homeostasis and represents a common denominator in virtually all neurological diseases. Activation of microglia, the principal immune effector cells of the brain, contributes to neuronal injury by release of neurotoxic products. Toll-like receptor 4 (TLR4), expressed on the surface of microglia, plays an important role in mediating lipopolysaccharide (LPS)-induced microglia activation and inflammatory responses. We have previously shown that curcumin and some of its analogues harboring an α,β-unsaturated 1,3-diketone moiety, able to coordinate the magnesium ion, can interfere with LPS-mediated TLR4-myeloid differentiation protein-2 (MD-2) signaling. Fluoroquinolone (FQ) antibiotics are compounds that contain a keto-carbonyl group that binds divalent ions, including magnesium. In addition to their antimicrobial activity, FQs are endowed with immunomodulatory properties, but the mechanism underlying their anti-inflammatory activity remains to be defined. The aim of the current study was to elucidate the molecular mechanism of these compounds in the TLR4/NF-κB inflammatory signaling pathway.

METHODS

The putative binding mode of five FQs [ciprofloxacin (CPFX), levofloxacin (LVFX), moxifloxacin, ofloxacin, and delafloxacin] to TLR4-MD-2 was determined using molecular docking simulations. The effect of CPFX and LVFX on LPS-induced release of IL-1β and TNF-α and NF-κB activation was investigated in primary microglia by ELISA and fluorescence staining. The interaction of CPFX and LVFX with TLR4-MD-2 complex was assessed by immunoprecipitation followed by Western blotting using Ba/F3 cells.

RESULTS

CPFX and LVFX bound to the hydrophobic region of the MD-2 pocket and inhibited LPS-induced secretion of pro-inflammatory cytokines and activation of NF-κB in primary microglia. Furthermore, these FQs diminished the binding of LPS to TLR4-MD-2 complex and decreased the resulting TLR4-MD-2 dimerization in Ba/F3 cells.

CONCLUSIONS

These results provide new insight into the mechanism of the anti-inflammatory activity of CPFX and LVFX, which involves, at least in part, the activation of TLR4/NF-κB signaling pathway. Our findings might facilitate the development of new molecules directed at the TLR4-MD-2 complex, a potential key target for controlling neuroinflammation.

Effect of the administration period of perioperative topical levofloxacin on normal conjunctival bacterial flora

PURPOSE

To assess the long-term and short-term effects of post-cataract surgery antibiotic therapy on the drug-resistance profile of normal conjunctival bacterial flora.

SETTING

Miyata Eye Hospital, Miyazaki, Japan.

DESIGN

Randomized prospective clinical trial.

METHODS

Patients aged 20 years or older who had cataract surgery between May and September 2015 were given levofloxacin 1.5% ophthalmic solution for 3 days preoperatively. The patients were randomly assigned to a 1-week postoperative group or a 1-month postoperative group according to postoperative administration duration. Conjunctival sacs were scraped for bacterial culturing before administration, 1 week postoperatively, at the completion of administration, and 1, 3, and 6 months after administration completion. The bacterial culture growth and minimum inhibitory concentrations (MICs) of levofloxacin against recovered strains of Staphylococcus epidermidis were assessed.

RESULTS

The study enrolled 104 patients. The MICs of levofloxacin against S epidermidis increased during levofloxacin administration compared with before administration in both groups and then declined after administration completion. However, by 3 months, the MICs in the 1-month group were approximately twice those in the 1-week group. Antibiotic susceptibility before administration, at completion of administration, and at 3 months was 73.6%, 20.2%, and 38.5%, respectively, in the 1-week group and 63.0%, 0.0%, and 19.3%, respectively, in the 1-month group. The results indicate that from completion of administration to 3 months, the susceptible strains were approximately 20% lower in the 1-month postoperative group than in the 1-week postoperative group.

CONCLUSION

Administration duration of perioperative levofloxacin 1.5% influenced the MICs and susceptibility of S epidermidis isolated from the conjunctival sac.

Immunobiological efficacy and immunotoxicity of novel synthetically prepared fluoroquinolone ethyl 6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylate

The present study examined the cytotoxicity, anti-cancer reactivity, and immunomodulatory properties of new synthetically prepared fluoroquinolone derivative 6-fluoro-8-nitro-4-oxo-1,4-dihydroquinoline-3-carboxylate (6FN) in vitro. The cytotoxicity/toxicity studies (concentrations in the range 1-100μM) are focused on the cervical cancer cells HeLa, murine melanoma cancer cells B16, non-cancer fibroblast NIH-3T3 cells and reconstructed human epidermis tissues EpiDerm™. The significant growth inhibition of cancer cells HeLa and B16 was detected. The cytotoxicity was mediated via apoptosis-associated with activation of caspase-9 and -3. After 72h of treatment, the two highest 6FN concentrations (100 and 50μM) induced toxic effect on epidermis tissue EpiDerm™, even the structural changes in tissue were observed with concentration of 100μM. The effective induction of RAW 264.7 macrophages cell-release of pro- and anti-inflammatory T_H1, T_H2 and T_H17 cytokines, with anti-cancer and/or anti-infection activities, respectively, has been revealed even following low-dose exposition.

Fluoroquinolones impair tendon healing in a rat rotator cuff repair model: a preliminary study

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.

Effects of awakening and the use of topical dexamethasone and levofloxacin on the cytokine levels in tears following corneal transplantation

Objectives. To study the short-term effect of eye opening and use of topical dexamethasone phosphate 0.1% and levofloxacin 0.5% on the cytokine levels in human tears. Methods. Prospective experimental design was used for tear collection from eyes of 10 healthy controls and 20 patients four days after penetrating keratoplasty (PKP) at awakening and after instilling dexamethasone or levofloxacin. The concentrations of different cytokines were measured by cytometric bead array. Results. At eye opening, IL-6 levels were higher in the PKP group as compared to the controls. Thirty minutes later, the released levels of IL-10, IL-13, IL-17, IFNγ, and CCL5 increased in controls, while CXCL8 decreased in both control and PKP groups. The release of the cytokines remained stable after 30 mins except for IFNγ, which showed a decrease in the controls following levofloxacin instillation. No short-term effects of the topically used dexamethasone and levofloxacin could be detected on the cytokine levels in controls and after PKP. Conclusions. Evidence of changes in the levels and time course of tear cytokines after awakening or eye opening could be established and the short-term confounding effects of dexamethasone and levofloxacin on the levels of released cytokines in human tears could be excluded.

Levofloxacin inhibits rhinovirus infection in primary cultures of human tracheal epithelial cells

Respiratory virus infections, including infections with rhinoviruses (RVs), are related to exacerbations of chronic obstructive pulmonary disease (COPD). A new quinolone antibiotic, levofloxacin (LVFX), has been used to treat bacterial infections that cause COPD exacerbations as well as bacterial infections that are secondary to viral infection in COPD patients. However, the inhibitory effects of LVFX on RV infection and RV infection-induced airway inflammation have not been studied. We examined the effects of LVFX on type 14 rhinovirus (RV14) (a major human RV) infection of human tracheal epithelial cells pretreated with LVFX. LVFX pretreatment reduced the RV14 titer, the level of cytokines in the supernatant, the amount of RV14 RNA in the cells after RV14 infection, and the cells' susceptibility to RV14 infection. LVFX pretreatment decreased the mRNA level of intercellular adhesion molecule 1 (ICAM-1), a receptor for RV14, in the cells and the concentration of the soluble form of ICAM-1 in the supernatant before RV14 infection. LVFX pretreatment also decreased the number and the fluorescence intensity of the acidic endosomes from which RV14 RNA enters the cytoplasm. LVFX pretreatment inhibited the activation of nuclear factor κB proteins, including p50 and p65, in nuclear extracts. LVFX pretreatment did not reduce the titers of RV2 (a minor human RV) but reduced the titers of RV15 (a major human RV). These results suggest that LVFX inhibits major-group rhinovirus infections in part by reducing ICAM-1 expression levels and the number of acidic endosomes. LVFX may also modulate airway inflammation in rhinoviral infections.

Systemic expression of cytokine production in patients with severe pneumococcal pneumonia: effects of treatment with a beta-lactam versus a fluoroquinolone

Bacterial alveolar invasion is followed by an inflammatory response. A systemic extension of the compartmentalized immune response has been described in patients with severe pneumonia. The data suggest that some antimicrobials may induce a differential release of cytokines. We conducted a prospective, randomized study in adult patients with severe pneumococcal pneumonia to measure the effects of ceftriaxone and levofloxacin in the systemic cytokine expression over time. Demographic, clinical characteristics, and severity scores were recorded. The serum concentrations of tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, IL-8, IL-10, and IL-1 receptor agonist were measured at 0, 24, 72, and 120 h. A total of 32 patients were included in the study. Both groups were homogeneous in terms of age, comorbidities, severity of disease, and corticosteroid or statin use. With the single exception of IL-1beta, all cytokines were detected in venous blood. All of the cytokines studied showed a similar pattern of progressive decrease over time. No significant differences in the concentrations of any of the cytokines studied were found, with the exception of TNF-alpha, for which lower concentrations were obtained at 120 h in the levofloxacin group (P = 0.014). Basal oxygen saturation (P = 0.034) and heart rate (P = 0.029) returned to normal values earlier in the levofloxacin arm. We demonstrated that in patients with severe pneumococcal pneumonia pro- and anti-inflammatory responses could be detected in venous blood, representing a systemic extension of the compartmentalized response. Treatment with a beta-lactam agent or a fluoroquinolone has different effects on cytokine production and its systemic expression, impacting the clinical course of the disease.

Treatment for chronic prostatitis/chronic pelvic pain syndrome: levofloxacin, doxazosin and their combination

INTRODUCTION

We performed a prospective, randomized study to examine the efficacies of levofloxacin and doxazosin alone and as a combination therapy in patients with National Institutes of Health (NIH) category III chronic prostatitis/chronic pelvic pain syndrome.

PATIENTS AND METHODS

Men with a NIH diagnosis of category III chronic prostatitis/chronic pelvic pain syndrome and who had experienced pelvic pain for more than 3 months during the last 6 months were enrolled. All patients underwent treatment for 6 weeks. The patients were assessed at baseline and after 2 and 6 weeks by using the NIH Chronic Prostatitis Symptom Index. Eighty-one men (average age 40.1 years) were randomized to either the levofloxacin group (n = 26), the doxazosin group (n = 26), or the combination group (n = 29).

RESULTS

The average baseline NIH Chronic Prostatitis Symptom Index total scores were 22.6, 22.4, and 24.1, respectively. At 6 weeks, the total scores were 11.2 (response rate 50.3%), 17.7 (response rate 21.1%), and 13.1 (response rate 45.6%), respectively. The levofloxacin group showed a higher response rate than the doxazosin group, not at 2 weeks but at 6 weeks (p < 0.001).

CONCLUSIONS

For a 6-week short-term treatment levofloxacin is more effective than doxazosin for chronic prostatitis/chronic pelvic pain syndrome. In addition, levofloxacin monotherapy was also more effective when compared with the combination therapy.

Immunomodulatory effect of gatifloxacin on mouse peritoneal macrophages in vitro and in models of endotoxin-induced rat conjunctivitis and rabbit bacterial keratitis

AIM

To determine the anti-inflammatory activity of gatifloxacin in ophthalmic use.

METHODS

The following 3 experiments were carried out. (1) Rabbits were inoculated intracorneally with methicillin-resistant Staphylococcus aureus and topically treated with gatifloxacin or levofloxacin. The severity of infection and viable bacterial count were assessed. (2) Thioglycollate-elicited mouse peritoneal macrophages were stimulated by Pseudomonas lipopolysaccharides (LPS) in the presence of graded concentrations of fluoroquinolones, and macrophage-derived tumor necrosis factor alpha (TNF-alpha) was assessed. (3) The effects of fluoroquinolones on TNF-alpha production were compared in an LPS-induced rat conjunctivitis model.

RESULTS

In the rabbit keratitis model, the ocular inflammation was significantly reduced by gatifloxacin as compared to levofloxacin but there was no significant difference between the groups in the number of viable bacteria. Gatifloxacin and levofloxacin suppressed TNF-alpha production in mouse macrophages in a concentration-dependent manner, and the effect of gatifloxacin was more potent than that of levofloxacin. Moxifloxacin exhibited no effect in this condition. In the rat conjunctivitis model, the tissue TNF-alpha level was significantly reduced only in the group instilled with gatifloxacin ophthalmic solution.

CONCLUSION

These results indicate that gatifloxacin has not only antibacterial activity but an anti-inflammatory action caused by at least inhibiting TNF-alpha production at the doses used in topical ophthalmic therapy.

Biphasic regulation of levofloxacin on lipopolysaccharide-induced IL-1β production

Fluoroquinolones have been known to exert modulatory activity on immune responses to microbial infection. However, the mechanism of this immunomodulation has not been well elucidated. In this study, we investigated the effect of levofloxacin on lipopolysaccharide (LPS)-induced production of interleukin-1beta (IL-1beta) in RAW264.7 cells. We showed that LPS-stimulated release of pre-synthesized IL-1beta was promoted by levofloxacin, in part via the p38 mitogen-activated protein kinase (MAPK) pathway. On the other hand, newly synthesized IL-1beta production was inhibited by levofloxacin. This immunoregulatory function of levofloxacin in the later phase as well as promotion of pre-synthesized IL-1beta release by levofloxacin in the early phase might be advantageous in the host defense to microbial pathogens.

The 6-fluoro-8-methoxy quinolone gatifloxacin down-regulates interleukin-8 production in prostate cell line PC-3

Fluoroquinolones exhibit immunomodulatory effects on monocytes and macrophages, in addition to their bactericidal activities. It remains unknown even whether the quinolones act directly on the prostate. This study was based on the understanding of the molecular mechanisms of the actions of the fluoroquinolones that can be used for the treatment of chronic prostatitis/chronic pelvic pain syndrome. We investigated whether the 6-fluroro-8-methoxy quinolone gatifloxacin (GFLX) affected the production and secretion of interleukin-8 (IL-8) in the prostate cell line PC-3. GFLX decreased the level of IL-8 release from unstimulated PC-3 cells. GFLX also attenuated IL-8 secretion from PC-3 cells stimulated with peptidoglycan, Mycoplasma hominis, phorbol ester, and tumor necrosis factor alpha (TNF-alpha), indicating that GFLX exhibits an anti-inflammatory effect on the prostate cell line. However, GFLX failed to alter activation of the NF-kappaB and AP-1 elicited by these stimulants. GFLX significantly attenuated the expression of IL-8 mRNA in TNF-alpha-stimulated PC-3 cells and down-regulated the transcriptional activity of the 5'-flanking region of the IL-8 gene from -1481 to +44 bp. The deletion construct without the 5'-flanking region from -1481 to -170 bp but not the construct without the region from -1481 to -188 bp reversed the suppressive effect of GFLX on IL-8 promoter activity. These results demonstrate that GFLX suppresses IL-8 expression in the prostate cell line by decreasing the promoter activity of the IL-8 gene.

Role of bacteria in chronic prostatitis/chronic pelvic pain syndrome

Throughout the past century, we have refined our understanding of prostatitis, moving from using a primarily clinical definition to considering it as a complex inflammatory condition. The inconsistency in identifying uropathogens in patients with symptoms of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) has led to controversy in therapeutic management. There is compelling evidence that the normal prostate has minimal inflammation and no bacteria. Clinicians using the Meares/Stamey criteria identified uropathogens localized to the prostate in only 6% to 8% of CP/CPPS patients. This suggests that bacteria may have a role in less than 10% of men with CP/CPPS. That some patients respond to antimicrobials could suggest that eradication of bacteria reduces symptoms. However, the beneficial effect of antimicrobial drugs may not be due to their antibacterial action, but to their anti-inflammatory action. The normal prostate shows minimal inflammation, but only 50% of CP/CPPS patients exhibit prostatic leukocytosis. Prudence demands that we examine the function of the white blood cells--the cytokines produced. Several basic science advances allowed new avenues of research regarding the detection of molecular evidence of causative uropathogens. New research brings new controversy and unexpected findings, but further refines our understanding of the immune system and the CP/CPPS disease process.

Anti-inflammatory effects of moxifloxacin on activated human monocytic cells: inhibition of NF-kappaB and mitogen-activated protein kinase activation and of synthesis of proinflammatory cytokines

We previously showed that moxifloxacin (MXF) exerts protective anti-inflammatory effects in immunosuppressed mice infected with Candida albicans by inhibiting interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) production in the lung. Immunohistochemistry demonstrated inhibition of nuclear factor (NF)-kappaB translocation in lung epithelium and macrophages in MXF-treated mice. In the present study we investigated the effects of MXF on the production of proinflammatory cytokines (i.e., IL-8, TNF-alpha, and IL-1beta) by activated human peripheral blood monocytes and THP-1 cells and analyzed the effects of the drug on the major signal transduction pathways associated with inflammation: NF-kappaB and the mitogen-activated protein kinases ERK and c-Jun N-terminal kinase (JNK). The levels of IL-8, TNF-alpha, and IL-1beta secretion rose 20- and 6.7-fold in lipopolysaccharide (LPS)-activated monocytes and THP-1 cells, respectively. MXF (5 to 20 microg/ml) significantly inhibited cytokine production by 14 to 80% and 15 to 73% in monocytes and THP-1 cells, respectively. In THP-1 cells, the level of NF-kappaB nuclear translocation increased fourfold following stimulation with LPS-phorbol myristate acetate (PMA), and this was inhibited (38%) by 10 microg of MXF per ml. We then assayed the degradation of inhibitor (I)-kappaB by Western blotting. LPS-PMA induced degradation of I-kappaB by 73%, while addition of MXF (5 microg/ml) inhibited I-kappaB degradation by 49%. Activation of ERK1/2 and the 46-kDa p-JNK protein was enhanced by LPS and LPS-PMA and was significantly inhibited by MXF (54 and 42%, respectively, with MXF at 10 microg/ml). We conclude that MXF suppresses the secretion of proinflammatory cytokines in human monocytes and THP-1 cells and that it exerts its anti-inflammatory effects in THP-1 cells by inhibiting NF-kappaB, ERK, and JNK activation. Its anti-inflammatory properties should be further assessed in clinical settings.

Immunomodulatory effects of quinolones

We review data on the in-vitro, ex-vivo, in-vivo, and clinical effects of fluoroquinolones on the synthesis of cytokines and their mechanisms of immunomodulation. In general, most fluoroquinolone derivatives superinduce in-vitro interleukin 2 synthesis but inhibit synthesis of interleukin 1 and tumour necrosis factor (TNF)alpha; furthermore, they enhance significantly the synthesis of colony-stimulating factors (CSF). Fluoroquinolones affect in-vivo cellular and humoral immunity by attenuating cytokine responses. Interleukins 10 and 12 have an important role in the functional differentiation of immunocompetent cells and trigger the initiation of the acquired immune response. In addition, certain fluoroquinolones were seen to enhance haematopoiesis by increasing the concentrations of CSF in the lung as well as in the bone marrow and shaft. Those fluoroquinolones exerting significant effects on haematopoiesis were those with a cyclopropyl moiety at position N1 of their quinolone core structure. Mechanisms that could explain the various immunomodulatory effects of fluoroquinolones include: (1) an effect on intracellular cyclic adenosine-3',5'-monophosphate and phosphodiesterases; (2) an effect on transcription factors such as nuclear factor (NF)kappaB, activator protein 1, NF-interleukin-6 and nuclear factor of activated T cells; and (3) a triggering effect on the eukaryotic equivalent of bacterial SOS response with its ensuing intracellular events. Further studies are required, especially in the clinical setting to exploit fully the potential of the immunomodulatory effect of fluoroquinolones during, for example, immunosuppression, chronic airway inflammatory diseases, and sinusitis.

Manipulation of the bacterial flora in inflammatory bowel disease

In this chapter we summarize the clinical and experimental data which indicate that bacteria, especially from the endogenous microflora, play a role in the pathogenesis of Crohn's disease, ulcerative colitis and pouchitis. We review the clinical trials, focusing on randomized controlled trials which used antibiotics or probiotics to treat situations of IBD or prevent recurrence, and we discuss the future of this approach.

Ciprofloxacin enhances the stimulation of matrix metalloproteinase 3 expression by interleukin-1beta in human tendon-derived cells. A potential mechanism of fluoroquinolone-induced tendinopathy

OBJECTIVE

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.

METHODS

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.

RESULTS

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.

CONCLUSION

Ciprofloxacin can selectively enhance MMP expression in tendon-derived cells. Such effects might compromise tendon microstructure and integrity.

Design of a multicenter randomized clinical trial for chronic prostatitis/chronic pelvic pain syndrome

OBJECTIVES

To describe the study design and rationale for the first placebo-controlled, randomized clinical trial to be conducted by the Chronic Prostatitis Collaborative Research Network sponsored by the National Institutes of Health.

METHODS

The clinical trial will use a 2 by 2 factorial design to evaluate four treatments: placebo, tamsulosin hydrochloride alone, ciprofloxacin alone, and tamsulosin hydrochloride and ciprofloxacin combined. The primary objectives are to compare the efficacy and safety endpoints in patients with chronic prostatitis/chronic pelvic pain syndrome. The study population consists of men with symptoms of discomfort or pain in the pelvic region for at least a 3-month period. One hundred eighty-four participants will be treated for 6 weeks and followed up for an additional 6 weeks. The primary endpoint is the change in the overall National Institutes of Health Chronic Prostatitis Symptom Index from baseline to 6 weeks. Secondary endpoints include a patient-reported global assessment of response and white blood cell counts and cultures in urine, expressed prostatic secretions, and semen. The evaluation of changes from 6 to 12 weeks will be used to assess the durability of the response.

RESULTS

This trial was opened to enrollment in July 2001. The study is expected to require 14 months of accrual and follow-up.

CONCLUSIONS

The issues considered in the design of this clinical trial may provide guidelines for future clinical trials in chronic prostatitis/chronic pelvic pain syndrome.

Effects of antimicrobial agents on spontaneous and endotoxin-induced cytokine release of human peripheral blood mononuclear cells

Because the immunomodulatory effects of antibiotics could possibly influence the degree of the systemic and local response to infection, knowledge of their intrinsic influence on the host's inflammatory response appears to be essential. Therefore, this study investigated the effects of frequently used antimicrobial agents (beta-lactams, quinolones gentamicin, vancomycin and metronidazole) on the in-vitro tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 production of isolated human peripheral blood mononuclear cells (PBMNC), cultured with or without endotoxin, in comparison with those effects obtained in a whole-blood assay system. In the presence of ciprofloxacin, ofloxacin, gentamicin, vancomycin, and metronidazole, a significant inhibition of the endotoxin-stimulated TNF-alpha production of human peripheral blood mononuclear cells (PBMNC) was found at therapeutic levels. Only ofloxacin showed a significant inhibitory influence on the endotoxin-induced IL-6 production of PBMNC. In the whole-blood assay, significant effects were not detectable. None of the antibiotics showed cytotoxicity. It is concluded that, at present, the direct immunological effects of antibiotics should be interpreted carefully with regard to the experimental conditions, and regardless of the therapeutic implications. To assess the potential direct immunomodulatory effect of antimicrobial agents, different cell culture procedures should be used.

Urethral reconstruction of strictures resulting from treatment of benign prostatic hypertrophy and prostate cancer

Urethral strictures commonly result from treatments for prostate disease, such as transurethral resection, radical prostatectomy, and radiotherapy. Treating these strictures can be difficult: it may be complicated by previous irradiation, and endoscopy often fails. We review the risk factors for development of strictures resulting from the treatment of prostate disease and discuss the success rates of both endoscopic and open therapies.

Microbial factors in inflammatory bowel disease

An unsolved puzzle in IBD research is whether germs, genes, or a combination of the two with excessive immune responses to gut-associated bacteria explains the pathogenesis of UC and CD. Whatever the answer, there is little doubt that microbial factors are involved intimately in IBD pathogenesis. Although a long search has failed to confirm a direct pathogenic role for a specific infectious agent, compelling evidence suggests that commensal enteric bacteria and their products provide a local environmental trigger that initiates and perpetuates IBD, reactivates quiescent disease, results in the frequent septic complications of CD, and contributes to the development of several extraintesinal manifestations. The most compelling evidence for involvement of the enteric flora in the pathogenesis of IBD has been generated from studies of animal models, which collectively support the view that IBD is due to genetically determined dysregulation of the mucosal immune response to luminal antigens derived from the normal bacterial flora. Although removing or dampening the dominant antigenic stimuli with antibiotics or probiotics is conceptually superior to the current array of immunosuppressive and anti-inflammatory agents that nonspecifically block the inflammatory cascade, more definitive, rigorously designed, controlled trials of treatments directed at the microflora are needed. Future research investigating mechanisms of tolerance to luminal bacteria and an understanding of how probiotics can manipulate the intestinal flora beneficially will bring clinicians closer to identifying potential therapeutic targets and unraveling the bacterial connection to IBD pathogenesis.

Immunomodulating activity of quinolones: review

Fluorinated quinolones exert their bactericidal activity by inhibiting bacterial type II topoisomerases. At therapeutic concentrations, quinolones superinduce interleukin-2 (IL-2) and interferon-gamma production by mitogen-activated human peripheral blood T lymphocytes. At the molecular level, a stronger activation of the nuclear factor AP-1 ('activator protein-1') is observed in cells incubated with ciprofloxacin, resulting in enhanced cytokine gene transcription. Several cytokine and immediate early (e.g., c-fos and c-jun) mRNAs are upregulated by ciprofloxacin, possibly reflecting a mammalian stress response. In cultures with murine splenocytes, quinolones enhance IL-3 and granulocyte-macrophage colony stimulating factor (GM-CSF) synthesis. The stimulation of these hematopoietic growth factors prolongs survival of mice with depressed bone marrow and prevents experimental antiphospholipid syndrome (APS). In contrast, quinolones inhibit both human and mouse monocytic IL-1 and TNF-alpha synthesis, an effect that is beneficial in rat experimental type II collagen induced arthritis and LPS-induced septic chock in mice. The intriguing immunomodulatory activities of fluoroquinolones warrant future investigations with new tailored derivatives.

Predictors of patient response to antibiotic therapy for the chronic prostatitis/chronic pelvic pain syndrome: a prospective multicenter clinical trial

PURPOSE

To our knowledge antibiotics are the most popular choice of therapy for all categories of the chronic prostatitis/chronic pelvic pain syndrome. We determine if culture, leukocyte and/or antibody status of prostate specific specimens predicts patient response to antibiotic therapy.

MATERIALS AND METHODS

Patients clinically diagnosed with the chronic prostatitis/chronic pelvic pain syndrome according to the National Institutes of Health (NIH) definition had a lower urinary tract evaluation that included standard microscopy and culture of prostate specific specimens, and determination of the ratio of voided bladder 3 and voided bladder 2 antibody levels against a panel of identified prostate pathogens (enzyme linked immunosorbent assay methodology). Symptom evaluation consisted of the NIH chronic prostatitis symptom index (derived) pain scale 0 to 21, symptom severity index scale 0 to 100, symptom frequency questionnaire scale 0 to 50 and quality of life scale 0 to 6. Patients were stratified according to microscopy, culture and immune status, were treated with 12 weeks of ofloxacin, and were assessed at 4, 12 and 24 weeks with symptom scores as well as global assessments.

RESULTS

Based on leukocyte and culture results, 102 evaluable patients were stratified into categories II (14%), IIIA (48%) and IIIB (38%) of the chronic prostatitis/chronic pelvic pain syndrome. Of the cases 23% were categorized as antibody positive and 77% as antibody negative. Average age was 42 +/- 10 years and 92% of patients were white. Of the patients 57% believed that they had moderate to marked improvement. All categories of the chronic prostatitis/chronic pelvic pain syndrome and patients in whom antibody was positive or negative had significant improvement in the NIH chronic prostatitis symptom index, symptom severity index, symptom frequency questionnaire and quality of life scores compared with baseline (p <0.001). There was no significant difference in patient response to the stratification based on culture, leukocyte, that is categories II, IIIA and IIIB had same beneficial response, or antibody status.

CONCLUSIONS

Culture, leukocyte and antibody status of prostate specific specimens does not predict antibiotic response in patients with the chronic prostatitis/chronic pelvic pain syndrome. The perceived beneficial effect of antibiotics needs to be evaluated in a randomized placebo controlled trial.

Recent advances in inflammatory bowel disease

The last decade has seen tremendous advances in our knowledge, which has led to genuine improvements in our understanding of the pathogenesis and management of inflammatory bowel disease (IBD). The combined power of cellular and molecular biology has begun to unveil the enigmas of IBD, and, consequently, substantial gains have been made in the treatment of IBD. Refinements in drug formulation have provided the ability to target distinct sites of delivery, while enhancing the safety and efficacy of older agents. Simultaneous progress in biotechnology has fostered the development of new agents that strategically target pivotal processes in disease pathogenesis. This article addresses our current understanding of the pathogenesis of IBD, including the latest developments in animal models and covers agents currently used in the treatment of IBD as well as emerging therapies.

Update in medical treatment of Crohn's disease

Crohn's disease is an inflammatory bowel disorder that has no known cause. The goal of medical treatment is to control active disease, induce and maintain clinical remission, and treat complications. Anti-inflammatory medications and immunomodulatory therapies are the primary treatment modalities for Crohn's disease. The categories of standard treatment include the 5-aminosalicylic acid compounds, corticosteroids, antibiotics, and immunomodulators. New biologic therapy has been developed to better target the immune mediators that are active in Crohn's disease. Infliximab is the first of the biologic agents approved for the treatment of fistulizing and active Crohn's disease. Despite medical advances in treatment, there is still no cure for Crohn's disease.

Therapy of inflammatory bowel disease

In the last decade, substantial gains have been made in the treatment of inflammatory bowel disease (IBD). Refinements in drug formulation have provided the ability to target distinct sites of delivery, enhancing the safety and efficacy of older agents. Immunosuppressive agents beyond corticosteroids have assumed a routine part in the care of patients with IBD. Moreover, as the century closes, we stand at the threshold of unprecedented advances in knowledge of the pathogenesis of ulcerative colitis and Crohn's disease. Simultaneous progress in biotechnology has fostered the development of new agents that strategically target pivotal processes in disease pathogenesis. This review covers agents currently used in the treatment of IBD and seeks to provide an overview of emerging therapies.

Novel therapies for inflammatory bowel disease

Looking back at successes and failures in newer approaches to treating IBD, it is tempting--although still difficult--to draw conclusions about pathogenesis. When a therapy proves effective, do clinicians truly know how it works? Even with a therapy as specific as anti-TNF antibody, it is not clear if the benefit is attributable to simple binding and clearance of TNF-alpha or to binding on the cell surface and subsequent deletion of the activated macrophage. When a drug appears to be less effective than preclinical models suggest, can failures in effectiveness from delivery or dosing be differentiated? The disappointing results of clinical trials with IL-10--so at odds with the prediction of benefit from animal models--bring into question the validity of those models as well as the soundness of design of the clinical trials on which efficacy of IL-10 is judged. The variability of response even to the most narrowly targeted agents suggests that these diseases are far more heterogeneous in humans than in their murine counterparts. Clinicians are only just beginning to recognize subclinical markers of response, and it may soon be possible to predict response on the basis of genetic composition. For the moment, however, the field of pharmacogenetics is embryonic. Challenges in developing new therapeutic strategies include not only identifying novel agents, but also improving the definitions of clinical endpoints and defining efficacy at the biologic level. Only through considered evaluation of clinical evidence may clinicians determine which therapies should remain novelties and which should become an accepted part of the armamentarium.