[Show abstract][Hide abstract] ABSTRACT: 6-Substituted 9-fluoroquino[3,2-b]benzo[1,4]thiazines - a new type of tetracyclic azaphenothiazines -were obtained from of 6H-9-fluoroquinobenzothiazine by the introduction of appropriate substituents to the thiazine nitrogen atom (alkyl, aminoalkyl, amidoalkyl, sulfonamidoalkyl and nitrogen half-mustard groups). The compounds displayed differential cytotoxic as well as antiproliferative actions against human peripheral blood mononuclear cells (PBMC) stimulated with phytohemagglutinin A (PHA). In addition, they suppressed lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-alpha) production by whole blood human cell cultures. Two compounds (4 and 15, with the propargyl and methanesulfonamidopropyl groups) were selected for further experiments because of lack of cytotoxicity and strong antiproliferative actions. Compound 4 showed strong suppressive actions on growth of L1210, SW948, A-431 and CX-1 tumor cell lines which were close to those of cisplatin, the reference drug (e.g. GI(50) of 2.28 mu g/mL vs. 1.86 mu g/mL for L1210 cells). Further, the compound appeared to be equally effective as cyclosporine A (CsA) in the inhibition of human two-way mixed lymphocyte reaction (MLR). The compound did not significantly inhibit interleukin 2 (IL-2)-induced growth of CTLL-2 cell line. In addition, inhibition of prostaglandin (PG) synthesis by indomethacin or block of PG receptors did not interfere with the inhibitory effect of the compound on PHA-induced cell proliferation. Therefore, it is likely that the compound acts by inhibiting cell cycle as proposed for other phenothiazines. Further studies are required for the elucidation of the mechanism of action and therapeutic utility of these compounds in more advanced in vivo models.
Full-text · Article · Jan 2015 · European Journal of Medicinal Chemistry
[Show abstract][Hide abstract] ABSTRACT: Our previous studies demonstrated that among phenothiazines several derivatives could be found showing strong antiproliferative actions and the property of inhibiting inducible tumor necrosis factor alpha (TNF a) production in human blood cultures. The aim of this investigation was to determine potential antimicrobial actions of forty four new phenothiazine derivatives with the quinobenzothiazine structure. The compounds showed differential antibacterial and antifungal activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans depending on the compound structures, concentrations and bacterial strains. More specifically, 6-(1-methyl- 2-piperidylethyl) quinobenzothiazine displayed strongest actions against S. aureus and E. coli whereas 6-methanesulfonylaminobutyl-9-methylthioquinobenzothiazine exhibited the most universal antimicrobial properties. The correlation between antimicrobial activity and the chemical structure of quinobenzothiazines was discussed.
Full-text · Article · Dec 2014 · Polish journal of microbiology / Polskie Towarzystwo Mikrobiologów = The Polish Society of Microbiologists
[Show abstract][Hide abstract] ABSTRACT: Reconstitution of the immune function in chemotherapy patients will lead to decreases in post-operative complications. A preliminary investigation showed that an isoxazole derivative R-13 (3,5-dimethyl-isoxazole[5,4-e]8H-triazepin-4-one) hydrochloride, given in a single oral dose to normal mice, induced significant increases in the content of CD4+ cells in the spleens and lymph nodes. That observation prompted the authors to assess the immune reconstituting effects of R-13 in mice pre-treated with cyclophosphamide (CP). Mice were given intraperitoneally (IP) a sublethal dose of CP (200 mg/kg) and then R-13 (as 20 µg IP doses, every 3 days post-CP treatment). Control mice, not treated with CP, received R-13 or the vehicle (DMSO in appropriate dilution). Blood leukocyte and splenocyte numbers, blood cell type levels, splenocyte spontaneous and ConA-induced proliferation, and delayed-type hypersensitivity (DTH) to ovalbumin (OVA) were investigated on day 15 post-CP treatment and five R-13 doses. The humoral immune response (antibody-forming cell development to sheep erythrocytes) was measured 30 days post-CP treatment and 10 R-13 doses. In CP-treated mice, five dosings with R-13 led to increases in numbers of splenocytes and blood leukocytes, as well as in spontaneous and ConA-induced splenocyte proliferation, relative to levels in mice that received only CP 15 days earlier. Blood analysis revealed decreases in neutrophil and eosinophil contents and an increased appearance of lymphocyte immature forms in all mice that received the R-13. Both cell-mediated responses to OVA and humoral immune response to sheep erythrocytes in CP-treated hosts were restored. Based on the data here, it is concluded that R-13 may be of potential value for reconstitution of the immune function of chemotherapy patients.
No preview · Article · Nov 2014 · Journal of Immunotoxicology
[Show abstract][Hide abstract] ABSTRACT: Lactoferrin belongs to the immunoregulatory milk proteins involved in iron metabolism as well in providing innate immunity to newborns. The protein has been the subject of numerous clinical studies.
The aim of this investigation was to evaluate the effects of bovine lactoferrins (bLF), differing in source and iron content, on spontaneous proliferation of human peripheral blood mononuclear cells (PBMC) and cytokine production by human whole blood cultures.
The following bLF preparations were used: partially iron saturated or devoid of iron bLF from milk and bLF from colostrum. The study was conducted on 12 healthy volunteers (men, 20-24 years old). The effects of bLFs on the proliferation of PBMC in four-day cultures was studied at 50-0.6 µg/mL concentration range and the rate of proliferation was determined using the MTT colorimetric method. TNF α and IL-6 levels, induced by the bLFs in 24 h whole blood cultures, were measured by ELISA.
The lactoferrins stimulated autologous proliferation of human peripheral blood mononuclear cells (PBMC) in a dose-dependent manner, with a comparable efficacy. This stimulation occurred both in the constant presence of bLFs in the cultures and also upon preincubation of PBMC with bLFs with subsequent exhaustive wash of cells. Only bLF from colostrum induced production of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in cultures of whole blood cells. This phenomenon took place predominantly at concentration of 50 µg/mL.
The results showed potent stimulation of the proliferative response of PBMC by bovine lactoferrin, associated with the induction of proinflammatory cytokines only in the case of colostral bLF. This observation may be of importance when high doses of bLF are used in therapy and by designing diet supplementation with this protein.
No preview · Article · Nov 2014 · Advances in Clinical and Experimental Medicine
[Show abstract][Hide abstract] ABSTRACT: Cyclolinopeptide A, naturally occurring immunomodulatory nonapeptide, was modified with S or R-γ(3)-bis(homophenylalanine) in positions 3 or 4, or both 3 and 4. The replacement of one or both Phe residues by γ(3)-hhPhe led to decrease of their conformational flexibility in the analogues in comparison to CLA. All cyclic peptides, except 11, exist as isomers with the cis Pro-Pro peptide bond. Cyclic peptide 11 with single modification S-γ(3)-hhPhe(4) exists as a mixture of two isomers and the major isomer (89%) contains all peptide bonds of the trans geometry. The peptides were subjected to several immunological tests in vitro and in vivo. Linear peptides 1-8, precursors of CLA analogues 9-16, were not toxic against human peripheral blood mononuclear cells (PBMC) but cyclic analogues showed dose-dependent toxicity with exception of peptide 11. Linear peptides did not inhibit mitogen-induced PBMC proliferation whereas cyclic ones inhibited the proliferation in a dose-dependent manner. The actions of linear and cyclic peptides with regard to lipopolysaccharide (LPS) -induced tumour necrosis factor alpha (TNF α) production in whole human blood cultures were differential but particularly suppressive in the case of linear compound 6. Therefore, for in vivo tests compounds 6 and 11 were selected. The compounds showed comparable, suppressive actions in induction and effector phases of delayed type hypersensitivity as well as in the carrageenan-induced foot pad edema in mouse models. In summary, linear peptide 6 and cyclic peptide 11 are attractive as potential immune suppressor drugs.
Full-text · Article · Sep 2014 · European Journal of Medicinal Chemistry
[Show abstract][Hide abstract] ABSTRACT: A new type of tricyclic azaphenothiazines— 1,8-diazaphenothiazines—was obtained in the reaction of 2,3-and 3,4-disubstituted pyridines. The reaction ran as the Smiles rearrangement. The 1,8-diazaphenothiazine system was determined using NOE experiment and 2D NMR spectra (COSY, HSQC, HMBC). 10H-1,8-diazaphenothi-azine was transformed into 10-derivatives with alkyl, aminoalkyl, amidoalkyl, sulfonamidoalkyl, and nitrogen half-mustard groups. The compounds were tested for their effects on phytohemagglutinin A-induced proliferative response of human peripheral blood mononuclear cells (PBMC) and lipopolysaccharide-induced tumor necrosis factor alpha production by human whole blood cultures. The compounds exhibited differential, dose-dependent inhibitory activities in these tests. All the compounds were low toxic against PBMC. The compounds showing the highest antiproliferative activity strongly inhibited the growth of leukemia L-1210 and colon cancer SW-948 cell lines, similarly as cisplatin, a reference drug.
Full-text · Article · Aug 2014 · Medicinal Chemistry Research
[Show abstract][Hide abstract] ABSTRACT: The aim of this study was to evaluate the immunoregulatory effects of recombinant human lactoferrin (rhLF) in two in vitro models: (1) the secondary humoral immune response to sheep erythrocytes (SRBC); and (2) the mixed lymphocyte reaction (MLR). We compared the non-sialylated glycoform of rhLF as expressed by glycoengineered Pichia pastoris with one that was further chemically sialylated. In an earlier study, we showed that sialylated rhLF could reverse methotrexate-induced suppression of the secondary immune response of mouse splenocytes to SRBC, and that the phenomenon is dependent on the interaction of lactoferrin (LF) with sialoadhesin (CD169). We found that the immunorestorative activity of sialylated rhLF is also dependent on its interaction with the CD22 antigen, a member of the immunoglobulin superfamily that is expressed by B lymphocytes. We also demonstrated that only sialylated rhLF was able to inhibit the MLR reaction. MLR was inhibited by bovine lactoferrin (bLF), a glycoform that has a more complex glycan structure. Desialylated bLF and lactoferricin, a bLF-derived peptide devoid of carbohydrates, did not express such inhibitory activity. We showed that the interaction of LF with sialic acid receptors is essential for at least some of the immunoregulatory activity of this glycoprotein.
[Show abstract][Hide abstract] ABSTRACT: Potential immunological activities of three compounds: RM54 and its two derivatives RM55 and RM56, were evaluated in several, selected in vitro and in vivo tests such as: mitogen-induced lymphocyte proliferation, cytokine production, the humoral immune response in vitro and carrageenan test. Leflunomide served as a reference drug. The studied compounds showed differential, generally immunosuppressive properties. RM56 exhibited stronger suppressive activities as compared to RM54 and RM55. In particular, RM56 displayed the strongest activity in suppression of the carrageenan inflammation that was correlated with strong suppression of the humoral immune response in vitro and lymphocyte proliferation. Density Functional Theory (DFT) was employed to shed a light on molecular properties of the investigated compounds. The geometrical parameters of the studied molecular structures were fully optimized at the B3LYP/6-311G(d,p) level. The atomic charges distribution derived on the base of the Mulliken population analysis was correlated with immunological activity of RM54, RM55 and RM56. The obtained relationships show that the isoxazole ring plays an important role in the observed immunological activities. We also suggest that due to strong anti-inflammatory and anti-proliferative properties of RM-56, potential therapeutic applications of this derivative can be broad.
No preview · Article · Apr 2014 · Acta poloniae pharmaceutica
[Show abstract][Hide abstract] ABSTRACT: Lactoferrin, an iron-binding protein found in high concentrations in mammalian exocrine secretions, is an important component of the host defense system. It is also a major protein of the secondary granules of neutrophils from which is released upon activation. Due to its potential clinical utility, recombinant human lactoferrin (rhLF) has been produced in various eukaryotic expression systems; however none of these are fully compatible with humans. Most of the biopharmaceuticals approved by the FDA for use in humans are produced in mammalian expression systems. The Chinese hamster ovary cells (CHO) have become the system of choice for proteins that require post-translational modifications, such as glycoproteins. The aim of this study was to scale-up expression and purification of rhLF in a CHO expression system, verify its glycan primary structure, and assess its biological properties in cell culture models. A stable CHO cell line producing >200mg/L of rhLF was developed and established. rhLF was purified by a single-step cation-exchange chromatography procedure. The highly homogenous rhLF has a molecular weight of approximately 80kD. MALDI-TOF mass spectrometric analysis revealed N-linked, partially sialylated glycans at two glycosylation sites, typical for human milk LF. This novel rhLF showed a protective effect against oxidative stress in a similar manner to its natural counterpart. In addition, rhLF revealed a modulatory effect on cellular redox via upregulation of key antioxidant enzymes. These data imply that the CHO-derived rhLF is fully compatible with the native molecule, thus it has promise for human therapeutic applications.
No preview · Article · Sep 2013 · Journal of Biotechnology
[Show abstract][Hide abstract] ABSTRACT: A new type of azaphenothiazines - tetracyclic quino[3,2-b]benzo[1,4]thiazines, possessing common substituents (H, CH3, Cl, Br, F, CF3, SCH3) in positions 8-10 and pharmacophoric aminoalkyl substituents in position 6, were obtained from diquinodithiin and 2,2'-dichloro-3,3'-diquinolinyl disulfide in several-step syntheses. Sixty one compounds, grouped as the 6H, 6-dialkylaminoalkyl, 6-acylaminoalkyl and sulfonylaminoalkyl derivatives, were tested for cytotoxicity, their effects on phytohemagglutin A (PHA)-induced proliferative response of human peripheral blood mononuclear cells (PBMC) and lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-α) production by these cells. The compounds exhibited differential inhibitory activities in these tests and significantly varied in terms of cytotoxicity. The most promising compounds were tested for growth inhibition of leukemia L-1210 cells, colon cancer SV-948 cells and epidermal carcinoma A-341 cells. The most active compounds exhibited anticancer activity against these cell lines comparable to that of cisplatin. The structure-activity relationship of the compounds were discussed.
Full-text · Article · Mar 2013 · European Journal of Medicinal Chemistry
[Show abstract][Hide abstract] ABSTRACT: Clinical trials are reviewed, involving proteins and peptides derived from milk (predominantly bovine), with the exception of lactoferrin, which will be the subject of another article. The most explored milk fraction is α-lactalbumin (LA), which is often applied with glycomacropeptide (GMP) - a casein degradation product. These milk constituents are used in health-promoting infant and adult formulae as well as in a modified form (HAMLET) to treat cancer. Lactoperoxidase (LCP) is used as an additive to mouth hygiene products and as a salivary substitute. Casein derivatives are applied, in addition, in the dry mouth syndrome. On the other hand, casein hydrolysates, containing active tripeptides, found application in hypertension and in type 2 diabetes. Lysozyme is routinely used for food conservation and in pharmaceutical products. It was successfully used in premature infants with concomitant diseases to improve health parameters. When used as prophylaxis in patients with scheduled surgery, it significantly reduced the incidence of hepatitis resulting from blood transfusion. Lysozyme was also used in infected children as an antimicrobial agent showing synergistic effects in combination with different antibiotics. Proline-rich polypeptide (PRP) was introduced to therapy of Alzheimer's disease patients. The therapeutic value of PRP was proved in several clinical trials and supported by studies on its mechanism of action. Concentrated immunoglobulin preparations from colostrum and milk of hyperimmunized cows showed efficacy in prevention of infections by bacteria, viruses and protozoa. A nutrition formula with milk-derived TGF-β2 (Modulen IBD®) found application in treatment of pediatric Crohn's disease. In conclusion, the preparations containing milk-derived products are safe and effective measures in prevention and treatment of infections as well as autoimmune and neoplastic diseases.
No preview · Article · Jan 2013 · Postępy Higieny i Medycyny Doświadczalnej (Advances in Hygiene and Experimental Medicine)