N-Acylated Ciprofloxacin Derivatives: Synthesis and In Vitro Biological Evaluation as Antibacterial and Anticancer Agents.

A novel series of N-acylated ciprofloxacin (CP) conjugates 1-21 were synthesized and screened as potential antimicrobial agents. Conjugates 1 and 2 were 1.25-10-fold more potent than CP toward all Staphylococci (minimal inhibitory concentration 0.05-0.4 µg/mL). Most of the chloro- (3-7), bromo- (8-11), and CF3-alkanoyl (14-16) derivatives expressed higher or comparable activity to CP against selected Gram-positive strains. A few CP analogues (5, 10, and 11) were also more effective toward the chosen clinical Gram-negative rods. Conjugates 5, 10, and 11 considerably influenced the phases of the bacterial growth cycle over 18 h. Additionally, compounds 2, 4-7, 9-12, and 21 exerted stronger tuberculostatic action against three Mycobacterium tuberculosis isolates than the first-line antitubercular drugs. Amides 1, 2, 5, 6, 10, and 11 targeted gyrase and topoisomerase IV at 2.7-10.0 µg/mL, which suggests a mechanism of antibacterial action related to CP. These findings were confirmed by molecular docking studies. In addition, compounds 3 and 15 showed high antiproliferative activities against prostate PC3 cells (IC50 2.02-4.8 µM), up to 6.5-2.75 stronger than cisplatin. They almost completely reduced the growth and proliferation rates in these cells, without a cytotoxic action against normal HaCaT cell lines. Furthermore, derivatives 3 and 21 induced apoptosis/necrosis in PC3 cells, probably by increasing the intracellular ROS amount, as well as they diminished the IL-6 level in tumor cells.

Conjugates of urolithin A with NSAIDs, their stability, cytotoxicity, and anti-inflammatory potential.

Urolithin A (UA, 1), a gut microbiota postbiotic metabolite is attributed to express interesting biological activities indicated by in vitro, in vivo and clinical studies. Due to its strong anti-inflammatory properties it is considered as a promising lead molecule for further drug development, however, its strong phase II metabolism, severely limits its oral application. Therefore, monoesterified UA derivatives with selected NSAIDs: ibuprofen (Mix 3a/3b), mefenamic acid (Mix 4a/4b), diclofenac (Mix 5a/5b) and aspirin (Mix 6a/6b) were designed. Performed array of stability assays indicated Mix 4a/4b as a most suitable candidate for further studies due to its exceptional stability in human plasma. Thus, we evaluated effects of Mix 4a/4b on cell viability as well as the impact on cytokines secretion in THP-1 derived macrophages and compared it to UA. At high concentration (50 µM) Mix 4a/4b expressed a cytotoxic effect, however at concentration of 5 µM it significantly suppressed TNF-α secretion, and significantly increased ani-inflammatory IL-10 secretion at 10 µM without affecting cell viability. This work has led to selection of a novel UA derivatives, which are stable in solutions and in human plasma as well as posess anti-inflammatory activity towards THP-1 macrophages at non-cytotoxic concentrations.

The New Face of a Well-Known Antibiotic: A Review of the Anticancer Activity of Enoxacin and Its Derivatives.

Enoxacin as a second-generation synthetic quinolone is known for its antibacterial action; however, in recent years there have been studies focusing on its anticancer potential. Interestingly, it turns out that compared to other fluoroquinolones, enoxacin exhibits uncommon cytotoxic properties. Besides its influence on apoptosis, the cell cycle and cell growth, it exhibits a regulatory action on microRNA biogenesis. It was revealed that the molecular targets of the enoxacin-mediated inhibition of osteoclastogenesis are vacuolar H+-ATPase subunits and the c-Jun N-terminal kinase signaling pathway, causing a decrease in cell invasiveness. Interestingly, the prooxidative nature of the subjected fluoroquinolone enhanced the cytotoxic effect. Crucial for the anticancer activity were the carboxyl group at the third carbon atom, fluorine at the seventh carbon atom and nitrogen at the eighth position of naphyridine. Modifications of the parent drug improved the induction of oxidative stress, cell cycle arrest and the dysregulation of microRNA. The inhibition of V-ATPase-microfilament binding was also observed. Enoxacin strongly affected various cancer but not normal cells, excluding keratinocytes, which suffered from phototoxicity. It seems to be an underestimated anticancer drug with pleiotropic action. Furthermore, its usage as a safe antibiotic with well-known pharmacokinetics and selectivity will enhance the development of anticancer treatment strategies. This review covers articles published within the years 2000-2021, with a strong focus on the recent years (2016-2021). However, some canonical papers published in twentieth century are also mentioned.

The Effect of Conjugation of Ciprofloxacin and Moxifloxacin with Fatty Acids on Their Antibacterial and Anticancer Activity.

Novel conjugates (CP) of moxifloxacin (MXF) with fatty acids (1m-16m) were synthesized with good yields utilizing amides chemistry. They exhibit a more pronounced cytotoxic potential than the parent drug. They were the most effective for prostate cancer cells with an IC50 below 5 µM for respective conjugates with sorbic (2m), oleic (4m), 6-heptenoic (10m), linoleic (11m), caprylic (15m), and stearic (16m) acids. All derivatives were evaluated against a panel of standard and clinical bacterial strains, as well as towards mycobacteria. The highest activity towards standard isolates was observed for the acetic acid derivative 14m, followed by conjugates of unsaturated crotonic (1m) and sorbic (2m) acids. The activity of conjugates tested against an expanded panel of clinical coagulase-negative staphylococci showed that the compound (14m) was recognized as a leading structure with an MIC of 0.5 µg/mL denoted for all quinolone-susceptible isolates. In the group of CP derivatives, sorbic (2) and geranic (3) acid amides exhibited the highest bactericidal potential against clinical strains. The M. tuberculosis Spec. 210 strain was the most sensitive to sorbic (2m) conjugate and to conjugates with medium- and long-chain polyunsaturated acids. To establish the mechanism of antibacterial action, selected CP and MXF conjugates were examined in both topoisomerase IV decatenation assay and the DNA gyrase supercoiling assay, followed by suitable molecular docking studies.

Design and Synthesis of Menthol and Thymol Derived Ciprofloxacin: Influence of Structural Modifications on the Antibacterial Activity and Anticancer Properties.

Sixteen new Ciprofloxacin derivatives were designed and successfully synthesized. In an in silico experiment, lipophilicity was established for obtained compounds. All compounds were screened for antimicrobial activity using standard and clinical strains. As for Gram-positive hospital microorganisms, all tested derivatives were active. Measured MICs were in the range 1-16 µg/mL, confirming high antimicrobial potency. Derivative 12 demonstrated activity against all standard Gram-positive Staphylococci, within the range of 0.8-1.6 µg/mL and was confirmed as the leading structure with MICs 1 µg/mL for S. pasteuri KR 4358 and S. aureus T 5591 (clinical strains). All compounds were screened for their in vitro cytotoxic properties via the MTT method. Three of the examined compounds (3, 11 and 16) showed good activity against cancer cells, and in parallel were found not to be cytotoxic toward normal cells. Doxorubicin SI ranged 0.14-1.11 while the mentioned three ranged 1.9-3.4. Selected Ciprofloxacin derivatives were docked into the crystal structure of topoisomerase II (DNA gyrase) in complex with DNA (PDB ID: 5BTC). In summary, leading structures were established (3, 11, 12 and 16). We have observed poor results in preformed studies for disubstituted derivatives, suggesting that 3-oxo-4-carboxylic acid core is the active DNA-gyrase binding site, and when structural changes were made in this fragment, there was an observed decrease in antibacterial potency.

Effect of Hydroxyl Groups Esterification with Fatty Acids on the Cytotoxicity and Antioxidant Activity of Flavones.

Flavonoids and polyunsaturated fatty acids due to low cytotoxicity in vitro studies are suggested as potential substances in the prevention of diseases associated with oxidative stress. We examined novel 6-hydroxy-flavanone and 7-hydroxy-flavone conjugates with selected fatty acids (FA) of different length and saturation and examined their cytotoxic and antioxidant potential. Our findings indicate that the conjugation with FA affects the biological activity of both the original flavonoids. The conjugation of 6-hydroxy-flavanone increased its cytotoxicity towards prostate cancer PC3 cells. The most noticeable effect was found for oleate conjugate. A similar trend was observed for 7-hydroxy-flavone conjugates with the most evident effect for oleate and stearate. The cytotoxic potential of all tested conjugates was not specific towards PC3 because the viability of human keratinocytes HaCaT cells decreased after exposure to all conjugates. Additionally, we showed that esterification of the two flavonoids decreased their antioxidant activity compared to that of the original compounds. Of all the tested compounds, only 6-sorbic flavanone showed a slight increase in antioxidant potential compared to that of the original compound. Our data show that conjugated flavonoids are better absorbed and enhance cytotoxic effects, but the presence of FA lowered the antioxidant potential.

Synthetic Transition from Thiourea-Based Compounds to Tetrazole Derivatives: Structure and Biological Evaluation of Synthesized New N-(Furan-2-ylmethyl)-1H-tetrazol-5-amine Derivatives.

Twelve novel derivatives of N-(furan-2-ylmethyl)-1H-tetrazol-5-amine were synthesized. For obtained compound 8, its corresponding substrate single crystals were isolated and X-ray diffraction experiments were completed. In the initial stage of research, in silico structure-based pharmacological prediction was conducted. All compounds were screened for their antibacterial and antimycobacterial activities using standard and clinical strains. The cytotoxic activity was evaluated against a panel of human cancer cell lines, in contrast to normal (HaCaT) cell lines, by using the MTT method. All examined derivatives were found to be noncytotoxic against normal cell lines. Within the studied group, compound 6 showed the most promising results in antimicrobial studies. It inhibited four hospital S. epidermidis rods' growth, when applied at the amount of 4 µg/mL. However, the most susceptible to the presence of compound 6 was S. epidermidis T 5501 851/19 clinical strain, for which the MIC value was only 2 µg/mL. Finally, a pharmacophore model was established based on lead compounds from this and our previous work.

Cytotoxicity Evaluation of Novel bis(2-aminoethyl)amine Derivatives.

Seven novel derivatives of bis(2-aminoethyl)amine were synthesized. For compounds 1 and 7 single crystals were isolated and X-ray diffraction experiments were done. Lipophilicity and drug likeness were calculated in the initial stage of research. All compounds were screened for their in vitro cytotoxic activity against a panel of human cancer cell lines, which is contrary to normal (HaCaT) cell lines, by using the MTT method. Studies were followed by lactate dehydrogenase assay, apoptotic activity, and interleukin-6 assay. Within the studied group, compound 6 showed the most promising results in all biological studies. The strongest influence in A549 cells was denoted for derivative 4, which inhibited interleukin release almost tenfold, as compared to the control.

Anticancer and antimicrobial effects of novel ciprofloxacin fatty acids conjugates.

Ciprofloxacin (CP) has a confirmed cytotoxic action on some cancerous cells, but in high, non-pharmacological concentrations. Considering features of natural fatty acids, such as biocompatibility, biodegradability and their increased cellular uptake by cancer cells, it seems that combining them with a drug could improve its bioavailability, and thus cytotoxicity. Therefore, the aim of this study was coupling of CP with saturated and unsaturated fatty acids, and evaluation of their cytotoxicity, apoptosis-inducing effects and inhibition of IL-6 release in human primary (SW480) and metastatic (SW620) colon cancer, metastatic prostate cancer (PC3) and normal (HaCaT) cell lines. The PC3 cell line was the most sensitive to the presence of the obtained conjugates. The value of IC50 for oleic acid conjugate (4) was 7.7 µM, and it was 12 times lower than for CP alone (101.4 µM). The studied derivatives induced late apoptosis in all cancer cell lines, but not in normal cells. The most potent apoptosis inducer was conjugate 4, that resulted in the highest percentage of PC3 cells in late apoptosis (81.5% ±â€¯3.9), followed by elaidic acid amide 5 (75% ±â€¯4.8). The strongest pro-apoptic effects on SW480 cells were demonstrated by conjugates of DHA (8) and sorbic (2) acids, whereas in SW620 cell lines, compounds 2 and 5 appeared to be the most effective. To establish the mechanism of cytotoxic action of derivatives 2, 4, 5, the level of interleukin-6 (IL-6) was measured. The compounds with the highest cytotoxic potential significantly decreased the release of IL-6 by cancer cells. Additionally, all conjugates were evaluated for their in vitro antimicrobial activity. Short chain amides - crotonic (1) and sorbic (2) - were the most active against Staphyloccoci. The second-mentioned amide has shown both strong antistaphylococcal and antitumor properties.

Development of (4-methoxyphenyl)-1H-tetrazol-5-amine regioisomers as a new class of selective antitubercular agents.

A series of halogenated (4-methoxyphenyl)-1H-tetrazol-5-amine regioisomers (1a-9a, 1b-9b) were synthesized from their corresponding thiourea analogues (1-9). The synthesis pathway was confirmed by an X-ray crystallographic studies of 1a, 1b and 5a. Title derivatives were tested for their in vitro antitubercular activity against standard, "wild-type" and atypical mycobacteria. The highest therapeutic potential was attributed to isomeric N-(bromophenyl)tetrazoles 8a and 9a. Their growth-inhibitory effect against multidrug-resistant Mycobacterium tuberculosis Spec. 210 was 8-16-fold stronger than that of the first-line tuberculostatics. Other new tetrazole-derived compounds were also more or equally effective towards that pathogen comparing to the established pharmaceuticals. Among non-tuberculous strains, Mycobacterium scrofulaceum was the most susceptible to the presence of the majority of tetrazole derivatives. The synergistic interaction was found between 9a and streptomycin, as well as the additivity of both 8a and 9a in pairs with isoniazid, rifampicin and ethambutol. None of the studied compounds displayed antibacterial or cytotoxic properties against normal and cancer cell lines, which indicated their highly selective antimycobacterial effects.

Anticancer effects of alloxanthoxyletin and fatty acids esters - In vitro study on cancer HTB-140 and A549 cells.

Alloxanthoxyletin, a natural occurring pyranocoumarin isolated from a number of plant sources, such as family of Rutaceae, and its synthetic derivatives show cytotoxic and antitumor activities. In the present study new eleven esters of alloxanthoxyletin and fatty acids were synthesized and evaluated for their anticancer toxicity. The structures of the compounds were confirmed by Proton Nuclear Magnetic Resonance (1H NMR), Carbon-13 Nuclear Magnetic Resonance (13C NMR) and High Resolution Mass Spectrometry (HRMS) analyses. For all compounds 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the cytotoxic effect on human melanoma cells (HTB-140), human epithelial lung carcinoma cells (A549) and human keratinocyte line (HaCaT). For the most active compounds (8-11) lactate dehydrogenase (LDH) assay to assess the level of cell damage as well as migration inhibition assay were performed. To explain the basic mechanism of cell death induction, the effect of derivatives 8-11 on early and late apoptosis in Annexin V-FITC/7-AAD flow cytometry analysis was investigated. The results indicate that human melanoma cells (HTB-140) and human epithelial lung carcinoma cells (A549) were more sensitive to new alloxanthoxyletin derivatives exposure compared to human keratinocytes (HaCaT). Both, the cytotoxicity and the migration tests showed a concentration-dependent inhibition of cell growth, although with a different degree of efficacy. Tested compounds induced apoptosis in cancer cells, however, derivatives 8, 9, 10 and 11 were found to be much more potent inducers of early apoptosis in HTB-140 cells than in A549 and HaCaT cells. To establish the potent mechanism of action of alloxanthoxyletin derivatives 8, 9, 10 and 11 on HaCaT, A549 and HTB-140 cells, the level of IL-6 was measured. Our results indicate, that tested compounds significantly decrease the release of IL-6 for all cancer cell lines.

Expression of ghrelin and its receptors in ovarian endometrioma.

Endometriosis is a common gynaecological disorder manifesting by implantation and growth of endometrial tissue outside the uterine cavity. The evidence accumulates that endometriosis may be associated with abrogated regulation of energy balance. Ghrelin is one of the most important orexigenic factor which may also play a role in regulation of inflammatory and angiogenic reactions. The present study was aimed at investigating expression profile of ghrelin and its receptors (GHSR1α and GHSR1ß) in endometriotic lesions. The study included ovarian cysts and peritoneal fluid specimens obtained laparoscopically from 20 women with revised American Fertility Society stage III or IV endometriosis. Expression of specific mRNAs was assessed by reverse transcription-polymerase chain reaction. Expression of ghrelin and GHSR1α protein was studied by immunohistochemical staining with specific antibodies. Ghrelin and its receptors mRNA expression was found in all tested specimens. Specific mRNAs for these factors were also expressed in the peritoneal leukocytes. Immunohistochemical staining revealed expression of ghrelin and GHSR1α both in glandular endometrioid epithelium and in some stromal cells, particularly in some fibroblasts, blood vessels and infiltrating leukocytes. Co-localization of ghrelin and its receptors strongly suggests that this neuropeptide may affect development and growth of endometriotic lesions and may influence local inflammatory and angiogenic response.

Elevated ghrelin levels in the peritoneal fluid of patients with endometriosis: associations with vascular endothelial growth factor (VEGF) and inflammatory cytokines.

OBJECTIVE: To study ghrelin concentrations in the peritoneal fluid of women with endometriosis and of control women without pelvic pathology and its associations with the levels of proinflammatory cytokines and vascular endothelial growth factor (VEGF). DESIGN: Case-control study. SETTING: University research institution and hospital. PATIENT(S): Forty-six nonobese women with laparoscopically and histopathologically confirmed endometriosis and 20 control women without pelvic pathology. INTERVENTION(S): Peritoneal fluid was aspirated during routine diagnostic laparoscopic examination. MAIN OUTCOME MEASURE(S): Concentrations of ghrelin and inflammatory cytokines (interleukin [IL]-1 beta, IL-6, tumor necrosis factor [TNF], and VEGF) in the peritoneal fluid were evaluated by specific enzyme immunoassay and enzyme-linked immunosorbent assays, respectively. RESULT(S): Ghrelin concentrations in the peritoneal fluid of women with endometriosis were significantly increased as compared with control subjects. Peritoneal ghrelin levels in patients with endometriosis were strongly positively associated with VEGF (r(s) = 0.625). There was no correlation between ghrelin and IL-1 beta, IL-6, or TNF. CONCLUSION(S): The results of the present study show that endometriosis is associated with increased peritoneal ghrelin levels. The association between ghrelin and endometriotic lesion vascularization remains to be elucidated.

Relationship between serum progesterone and tumor necrosis factor production in postmenopausal women undergoing estrogen/medroxyprogesterone therapy.

Changes in tumor necrosis factor (TNF) production by lipopolysaccharide-stimulated peripheral blood mononuclear cells significantly correlated with serum P levels in postmenopausal women subjected to estrogen/medroxyprogesterone therapy. This may suggest that low physiologic or hormone therapy-related changes of serum P in healthy postmenopausal women may affect an ability of peripheral blood mononuclear leukocytes to produce TNF, thus having an impact on a variety of TNF-dependent physiologic and pathologic phenomena.

Effect of estrogen/progesterone hormone replacement therapy on natural killer cell cytotoxicity and immunoregulatory cytokine release by peripheral blood mononuclear cells of postmenopausal women.

Sex steroids are known to affect immune responses; however, information on immunomodulatory effects of estrogen/progesterone hormone replacement therapy (HRT) is still limited. Therefore, the present study aimed to investigate the effect of estrogen/medroxyprogesterone HRT on natural killer (NK) cell cytotoxicity and immunoregulatory cytokine (IL-2, IL-4 and IFN-gamma) release by phytohemaglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) from 15 selected healthy postmenopausal women. NK cell cytotoxicity, cytokine production and serum levels of 17beta-estradiol (E2), progesterone (P) and FSH were tested in each patient before and after 90-days HRT. NK cell cytotoxicity was tested by (51)Cr-release assay using K562 erythroleukemic cells as target. Specific cytokine production and serum hormone levels were evaluated by enzyme-linked immunosorbent assay (ELISA) and immunochemiluminescent assays, respectively. HRT resulted in a significant decrease of Kupperman index, an increase of E2 and a decrease of FSH levels. These changes were associated with a significant decrease of NK cell cytotoxicity, IL-2 and IFN-gamma production. The levels of IL-4 production remained unchanged. Changes of NK cell cytotoxicity and cytokine release in individual patients did not correlate with changes of serum sex hormone levels. Nevertheless, the present results imply strongly that estrogen/progesterone HRT may affect cell-mediated immunity, thus being a potential factor influencing development and course of autoimmune disorders and neoplastic diseases.

Susceptibility to ovarian endometriosis in Polish population is not associated with HLA-DRB1 alleles.

BACKGROUND: Endometriosis is associated with inflammatory autoimmune reactions; however, aetiopathogenesis of the disease is still poorly understood. While autoimmune disorders are often associated with particular HLA alleles, the possible involvement of HLA in the aetiopathogenesis of endometriosis is still a subject of controversy. The aim of the study was to examine the distribution of HLA-DRB1 alleles in women with endometriosis. To ensure homogeneity of the studied group, only women with ovarian endometrial cysts were included. METHODS: The study included 65 Polish patients of Caucasian origin in whom ovarian endometriosis had been confirmed by laparoscopic and histopathological examinations. HLA-DRB1 alleles were typed using a reverse slot blot method. A frequency of particular HLA-DRB1 alleles in patients was compared with that of a control group of 700 unrelated ethnically matched individuals as well as 193 age-matched women without endometriosis. RESULTS: No statistically significant differences were found in the distribution of HLA-DRB1 alleles in patients with ovarian endometriosis as compared with control populations. CONCLUSIONS: The results of the present study show that ovarian endometriosis is not associated with particular HLA-DRB1 allele(s). This may suggest that aetiology of this form of endometriosis may be not primarily associated with class II HLA-mediated autoimmune reactions.