The Novel Ketoprofen Amides - Synthesis and Biological Evaluation as Antioxidants, Lipoxygenase Inhibitors and Cytostatic Agents

The Unresolved Pathophysiology of Lymphedema

Lymphedema is the clinical manifestation of impaired lymphatic transport. It remains an under-recognized and under-documented clinical condition that still lacks a cure. Despite the substantial advances in the understanding of lymphatic vessel biology and function in the past two decades, there are still unsolved questions regarding the pathophysiology of lymphedema, especially in humans. As a consequence of impaired lymphatic drainage, proteins and lipids accumulate in the interstitial space, causing the regional tissue to undergo extensive and progressive architectural changes, including adipose tissue deposition and fibrosis. These changes are also associated with inflammation. However, the temporal sequence of these events, the relationship between these events, and their interplay during the progression are not clearly understood. Here, we review our current knowledge on the pathophysiology of lymphedema derived from human and animal studies. We also discuss the possible cellular and molecular mechanisms involved in adipose tissue and collagen accumulation during lymphedema. We suggest that more studies should be dedicated to enhancing our understanding of the human pathophysiology of lymphedema to pave the way for new diagnostic and therapeutic avenues for this condition.

Examining barbiturate scaffold for the synthesis of new agents with biological interest

Aim: Barbiturates have a long history of being used as drugs presenting wide varieties of biological activities (antimicrobial, anti-urease and antioxidant). Reactive oxygen species are associated with inflammation implicated in cancer, atherosclerosis and autoimmune diseases. Multitarget agents represent a powerful approach to the therapy of complicated inflammatory diseases. Results: A novel series of barbiturates has been synthesized and evaluated in several in vitro assays. Compound 16b (lipoxygenases inhibitor, 55.0 μM) was found to be a cyclooxygenase-2 inhibitor (27.5 μM). Compound 8b was profiled as a drug-like candidate. Conclusion: The barbiturate core represents a new scaffold for lipoxygenases inhibition, and the undertaken derivatives show promise as multiple-target agents to combat inflammatory diseases.

Use of non-steroidal anti-inflammatory drugs in porcine health management

OBJECTIVE

Treatment of inflammation and pain management is an important topic in the welfare of pigs. It is very difficult for veterinary practitioners to choose the most appropriate product for a certain problem. This review aims to summarise and discuss the characteristics of different non-steroidal anti-inflammatory drugs (NSAIDs), as well as paracetamol and metamizole, available for pigs in the European Union.

METHODS

The databases Pubmed, Google Scholar, CliniPharm CliniTox and European Medicines Agency were searched. Relevant terms (eg,'meloxicam', 'fever', 'swine', 'pig', 'inflammation', 'castration', 'pain') were used to search for original articles, reviews and books. Only peer-reviewed articles were used. References from studies were also analysed in order to find additional relevant studies.

CONCLUSION

Studies which have investigated the efficacy of NSAIDs for different conditions, using different treatment regimens, are scarce. Most studies focused on the efficacy of NSAID-related pain alleviation in piglet castration, as well as the anti-inflammatory potential of NSAIDs in experimental inflammation models. Little research has been carried out on the use of metamizole, tolfenamic acid, paracetamol and sodium salicylate and their effect in pigs.

Chloroquine Urea Derivatives: Synthesis and Antitumor Activity in Vitro

In the current paper, we describe the design, synthesis and antiproliferative screening of novel chloroquine derivatives with a quinoline core linked to a hydroxy or halogen amine through a flexible aminobutyl chain and urea spacer. Synthetic pathway leading to chloroquine urea derivatives 4-10 includes two crucial steps: i) synthesis of chloroquine benzotriazolide 3 and ii) formation of urea derivatives through the reaction of compound 3 with the corresponding amine. Testing of antiproliferative activity against four human cancer cell lines revealed that chloroquine urea derivatives 9 and 10 with aromatic moieties show activity at micromolar concentrations. Therefore, these molecules represent interesting lead compounds that might provide an insight into the design of new anticancer agents.

Pilot studies demonstrate the potential benefits of antiinflammatory therapy in human lymphedema

BACKGROUND

Lymphedema is a common condition affecting millions around the world that still lacks approved medical therapy. Because ketoprofen, an NSAID, has been therapeutic in experimental lymphedema, we evaluated its efficacy in humans.

METHODS

We first performed an exploratory open-label trial. Patients with either primary or secondary lymphedema received ketoprofen 75 mg by mouth 3 times daily for 4 months. Subjects were evaluated for changes in histopathology, with skin thickness, limb volume, and tissue bioimpedance changes serving as secondary endpoints. Based on our encouraging findings, we next conducted a placebo-controlled trial, with the primary outcome defined as a change in skin thickness, as measured by skin calipers. Secondary endpoints for this second study included histopathology, limb volume, bioimpedance, and systemic inflammatory mediators.

RESULTS

We enrolled 21 lymphedema patients in the open-label trial, from November 2010 to July 2011. Histopathology and skin thickness were significantly improved at 4 months compared with baseline. In the follow-up, double-blind, placebo-controlled trial, we enrolled 34 patients from August 2011 to October 2015, with 16 ketoprofen recipients and 18 placebo-treated subjects. No serious adverse events occurred. The ketoprofen recipients demonstrated reduced skin thickness, as well as improved composite measures of histopathology and decreased plasma granulocyte CSF (G-CSF) expression.

CONCLUSION

These 2 exploratory studies together support the utility of targeted antiinflammatory therapy with ketoprofen in patients with lymphedema. Our results highlight the promise of such approaches to help restore a failing lymphatic circulation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02257970.

Leukotriene B4 antagonism ameliorates experimental lymphedema

Acquired lymphedema is a cancer sequela and a global health problem currently lacking pharmacologic therapy. We have previously demonstrated that ketoprofen, an anti-inflammatory agent with dual 5-lipoxygenase and cyclooxygenase inhibitory properties, effectively reverses histopathology in experimental lymphedema. We show that the therapeutic benefit of ketoprofen is specifically attributable to its inhibition of the 5-lipoxygenase metabolite leukotriene B₄ (LTB₄). LTB₄ antagonism reversed edema, improved lymphatic function, and restored lymphatic architecture in the murine tail model of lymphedema. In vitro, LTB₄ was functionally bimodal: Lower LTB₄ concentrations promoted human lymphatic endothelial cell sprouting and growth, but higher concentrations inhibited lymphangiogenesis and induced apoptosis. During lymphedema progression, lymphatic fluid LTB₄ concentrations rose from initial prolymphangiogenic concentrations into an antilymphangiogenic range. LTB₄ biosynthesis was similarly elevated in lymphedema patients. Low concentrations of LTB₄ stimulated, whereas high concentrations of LTB₄ inhibited, vascular endothelial growth factor receptor 3 and Notch pathways in cultured human lymphatic endothelial cells. Lymphatic-specific Notch1^-/- mice were refractory to the beneficial effects of LTB₄ antagonism, suggesting that LTB₄ suppression of Notch signaling is an important mechanism in disease maintenance. In summary, we found that LTB₄ was harmful to lymphatic repair at the concentrations observed in established disease. Our findings suggest that LTB₄ is a promising drug target for the treatment of acquired lymphedema.

In Vitro and In Silico Antidiabetic and Antimicrobial Evaluation of Constituents from Kickxia ramosissima (Nanorrhinum ramosissimum)

Background and Aims:Kickxia ramosissima (Wall.) Janch (or Nanorrhinum ramosissimum (Wall.) Betsche is a well-known medicinal plant in Pakistan that is traditionally used in diabetic and inflammatory conditions. Because little information is available on its phytochemical composition, a range of constituents were isolated and evaluated in vitro in assays related to the traditional use.

Methods: Dried whole plant material was extracted and chromatographically fractionated. Isolated constituents were evaluated in silico and in vitro in assays related to the traditional use against diabetes (inhibition of α-glucosidase activity; inhibition of advanced glycation endproducts) and in inflammatory conditions (inhibition of AAPH induced linoleic acid peroxidation, inhibition of 15-LOX, antimicrobial activity).

Results: Phytochemical analysis of the extracts and fractions led to isolation of 7 compounds, including the iridoids kickxiasine (being a new compound), mussaenosidic acid, mussaenoside and linarioside; the flavonoids pectolinarigenin and pectolinarin; and 4-hydroxy-benzoic acid methyl ester. The iridoids showed weak antiglycation activity. The flavonoids, however, showed interesting results as pectolinarigenin was highly active compared to pectolinarin. In the α-glucosidase inhibition assay, only weak activity was observed for the iridoids. However, the flavonoid pectolinarigenin showed good activity, followed by pectolinarin. In the 15-LOX experiment, moderate inhibition was recorded for most compounds, the iridoids mussaenosidic acid and mussaenoside being the most active. In the AAPH assay, weak or no inhibition was recorded for all compounds. The in silico assays for the α-glucosidase and 15-LOX assays confirmed the results of respective in vitro assays. Pectolinarigenin showed moderate antimicrobial activity against Staphylococcus aureus, Plasmodium falciparum K1, and Trypanosoma cruzi, but it was not cytotoxic on a human MRC-5 cell line.

Conclusion: Our findings may in part contribute to explain the traditional use of K. ramosissima.

Design, Synthesis and Biological Evaluation of Novel Primaquine-Cinnamic Acid Conjugates of the Amide and Acylsemicarbazide Type

In this paper design and synthesis of a scaffold comprising primaquine (PQ) motif and cinnamic acid derivatives (CADs) bound directly (compounds 3a-k) or via a spacer (compounds 7a-k) are reported. In the first series of compounds, PQ and various CADs were connected by amide bonds and in the second series by acylsemicarbazide functional groups built from the PQ amino group, CONHNH spacer and the carbonyl group originating from the CADs. PQ-CAD amides 3a-k were prepared by a simple one-step condensation reaction of PQ with a series of CAD chlorides (method A) or benzotriazolides 2 (method B). The synthesis of acylsemicarbazides 7a-k included activation of PQ with benzotriazole, preparation of PQ-semicarbazide 6 and its condensation with CAD chlorides 4. All synthesized PQ-CAD conjugates were evaluated for their anticancer, antiviral and antioxidative activities. Almost all compounds from series 3 were selective towards the MCF-7 cell line and active at micromolar concentrations. The o-fluoro derivative 3h showed high activity against HeLa, MCF-7 and in particular against the SW 620 cell line, while acylsemicarbazide 7f with a benzodioxole ring and 7c, 7g and especially 7j with methoxy-, chloro- or trifluoromethyl-substituents in the para position showed high selectivity and high inhibitory activity against MCF-7 cell line at micromolar (7c, 7f, 7g) and nanomolar (7j) levels. Acylsemicarbazide derivatives with trifluoromethyl group(s) 7i, 7j and 7k showed specific activity against human coronavirus (229E) at concentrations which did not alter the normal cell morphology. The same compounds exerted the most potent reducing activity in the DPPH test, together with 7d and 7g, while methoxy (compounds 7c-e), benzodioxole (7f), p-Cl (7g) and m-CF₃ (7i) acylsemicarbazides and amide 3f presented the highest LP inhibition (83%-89%). The dimethoxy derivative 7d was the most potent LOX inhibitor (IC50 = 10 μΜ). The performed biological tests gave evidence of acylsemicarbazide functional group as superior binding group in PQ-CAD conjugates.

Toward chelerythrine optimization: Analogues designed by molecular simplification exhibit selective growth inhibition in non-small-cell lung cancer cells

A series of novel chelerythrine analogues was designed and synthesized. Antitumor activity was evaluated against A549, NCI-H1299, NCI-H292, and NCI-H460 non-small-cell lung cancer (NSCLC) cell lines in vitro. The selectivity of the most active analogues and chelerythrine was also evaluated, and we compared their cytotoxicity in NSCLC cells and non-tumorigenic cell lines, including human umbilical vein endothelial cells (HUVECs) and LL24 human lung fibroblasts. In silico studies were performed to establish structure-activity relationships between chelerythrine and the analogues. The results showed that analogue compound 3f induced significant dose-dependent G0/G1 cell cycle arrest in A549 and NCI-H1299 cells. Theoretical studies indicated that the molecular arrangement and electron characteristics of compound 3f were closely related to the profile of chelerythrine, supporting its activity. The present study presents a new and simplified chelerythrinoid scaffold with enhanced selectivity against NSCLC tumor cells for further optimization.

A convenient synthesis of new NSAID esters containing amino acid, urea and amide moieties

Abstract A convenient synthetic method for the preparation of novel NSAID twin esters 6a-i containing amino acid residue, urea and amide moieties has been developed. The synthetic pathway applied for the preparation of target compounds and key intermediates 1-benzotriazolecarboxylic acid chloride (1), NSAID benzotriazolides 2a-c and N-(1-benzotriazolecarbonyl)-amino acids 3a-d involved benzotriazole as a synthetic auxiliary. The final preparation step of esters 6a-i included the solvent-free reaction of compounds 2a-c with amino acid derivatives 5a-g, bearing two hydroxyl groups, one at each terminal, beside urea and amide functionalities.

Synthesis and quantitative structure-activity relationship study of substituted imidazophosphor ester based tetrazolo[1,5-b]pyridazines as antinociceptive/anti-inflammatory agents

A high-yielding general synthesis of imidazophosphor ester based tetrazolo[1,5-b]pyridazines is described. A conjugated reaction between 3,6-diazidopyridazine and different types of phosphonyl carbanion reagents followed by intramolecular cyclization afforded the target products, by using sodium ethanolate solution as a reaction medium. Among the products, five compounds, at a dose of 50 mg per kilogram body weight, showed a notable antinociceptive and anti-inflammatory activity without toxic side-effects.

Minor iridoids from Scutellaria albida ssp. albida. Inhibitory potencies on lipoxygenase, linoleic acid lipid peroxidation and antioxidant activity of iridoids from Scutellaria sp

A new iridoid glycoside, 6'-O-E-caffeoyl-mussaenosidic acid , in addition to one known aglycon, four known triterpenes and one known flavonoid, were isolated from the aerial parts of Scutellaria albida subsp. albida. Furthermore, 12 iridoids with similar structures isolated from Scutellaria sp., were examined for their inhibitory potency on lipoxygenase and lipid peroxidation, as well as their antioxidant activity, in comparison to known antioxidants e.g. caffeic acid, nordihydroguaretic acid (NDGA) and trolox. AAPH, DPPH and soybean lipoxygenase (LOX) assays were used for the tests. This investigation led to interesting observations considering the Structure-Activity Relationship. According to our results, the presence of a p-coumaroyl group optimized and even dramatically changed the biological responses of the investigated iridoids.

Novel NSAID 1-acyl-4-cycloalkyl/arylsemicarbazides and 1-acyl-5-benzyloxy/hydroxy carbamoylcarbazides as potential anticancer agents and antioxidants

The novel 1-acyl-4-cycloalkyl/arylsemicarbazides (5a-y) and 1-acyl-5-benzyloxy/hydroxycarbamoylcarbazides (8a-f) derived from the nonsteroidal anti-inflammatory drugs ibuprofen, fenoprofen and reduced ketoprofen were prepared, fully chemically characterized and evaluated for their cytostatic, antiviral and antioxidant activities. Compounds 5 and 8 consist of a region rich in electronegative atoms (five to nine nitrogen and oxygen atoms) framed by aryl or cycloalkyl residues on one or both terminal ends. The synthetic pathways applied for the preparation of the title compounds involved a benzotriazole as a synthetic auxiliary in several steps. Three of the tested compounds, namely 4-benzhydryl-1-[2-(3-phenoxyphenyl)propanoyl]semicarbazide (5l), 4-benzhydryl-1-[2-(3-benzylphenyl)propanoyl]semicarbazide (5s), and 4-benzhydryl-1-[2-(4-isobutylphenyl)propanoyl]semicarbazide (5f) showed pronounced antiproliferative activity in vitro against six cancer cell lines (IC(50)=3-23 μM). The same compounds highly inhibited soybean lipoxygenase (IC(50)=60 and 51.5 μM) and lipid peroxidation as well (99, 88 and 74%, respectively). 4-Benzyloxy-1-[2-(4-isobutylphenyl)propanoyl]semicarbazide (5t) and 5-benzyloxycarbamoyl-1-[2-(3-benzylphenyl)propanoyl]carbazide (8c) exerted complete lipid peroxidation inhibition. Semicarbazides 5w-y and carbazides 8d-f bearing a hydroxamic acid/hydroxyurea moiety showed a modest antiradical activity in DPPH test, while the best radical scavenger was 1-(1-benzotriazolecarbonyl)-4-benzyloxysemicarbazide (7). None of the compounds were inhibitory to a broad panel of DNA and RNA viruses in the cell culture at subtoxic concentrations.

New sorafenib derivatives: synthesis, antiproliferative activity against tumour cell lines and antimetabolic evaluation

Sorafenib is a relatively new cytostatic drug approved for the treatment of renal cell and hepatocellular carcinoma. In this report we describe the synthesis of sorafenib derivatives 4a–e which differ from sorafenib in their amide part. A 4-step synthetic pathway includes preparation of 4-chloropyridine-2-carbonyl chloride hydrochloride (1), 4-chloro-pyridine-2-carboxamides 2a–e, 4-(4-aminophenoxy)-pyridine-2-carboxamides 3a–e and the target compounds 4-[4-[[4-chloro-3-(trifluoromethyl)phenyl]carbamoylamino]-phenoxy]-pyridine-2-carboxamides 4a–e. All compounds were fully chemically characterized and evaluated for their cytostatic activity against a panel of carcinoma, lymphoma and leukemia tumour cell lines. In addition, their antimetabolic potential was investigated as well. The most prominent antiproliferative activity was obtained for compounds 4a–e (IC₅₀ = 1-4.3 μmol·L⁻¹). Their potency was comparable to the potency of sorafenib, or even better. The compounds inhibited DNA, RNA and protein synthesis to a similar extent and did not discriminate between tumour cell lines and primary fibroblasts in terms of their anti-proliferative activity.

Primaquine-NSAID twin drugs: Synthesis, radical scavenging, antioxidant and Fe2+ chelating activity

Novel primaquine conjugates with non-steroidal anti-inlammatory drugs (PQ-NSAIDs, 4a-h) were prepared, fully chemically characterized and screened for radical scavenging and antioxidant activities. The synthetic procedure leading to twin drugs 4a-h involved two steps: i) preparation of NSAID benzotriazolides 3a-h from the corresponding NSAID (ibuprofen, ketoprofen, fenoprofen, ketoprofen hydroxy and methylene analogues, diclofenac or indomethacin) and benzotriazole carboxylic acid chloride (BtCOCl, 1), ii) reaction of intermediates 3a-h with PQ. The prepared PQ-NSAIDs exerted moderate activities in the DPPH free radical test and β-carotene-linoleic acid assay. Moreover, ketoprofen derivatives 4d and 4b demonstrated a notable Fe2+ chelating ability as well. On the other hand, negligible antiproliferative and antituberculotic effects of conjugates 4a-h were observed.