Synthesis and antiprotozoal activity of original porphyrin precursors and derivatives

Biomolecule-Producing Probiotic Bacterium Lactococcus lactis in Free or Nanoencapsulated Form for Endometritis Treatment and Fertility Improvement in Buffaloes

A Lactococcus (L.) lactis strain producing antimicrobial and anti-inflammatory biomolecules (mainly 1,4-Diaza-2,5-dioxobicyclo[4.3.0]nonanes and pyrazine-derivatives) was tested for its capacity to cure clinical endometritis in buffaloes compared to conventional antibiotic-based treatment. Clinical endometritis-diagnosed buffaloes (n = 16/group) were infused intrauterine with four doses of 109 CFU-free (FLC group) or nanoencapsulated L. lactis (NLC group) and compared to those that received three doses of saline + a single dose of 500 mg cephapirin benzathin (AB group) or four doses of saline (control, C group) every other day. Endometrium samples were analyzed for cytological (polymorphonuclear cells, PMN), bacteriological, and proinflammatory mRNA expression. Uterine wash and blood samples were collected to determine proinflammatory cytokine concentrations and metabolites in the blood samples. The reproductive performance of buffaloes was assessed. Compared to the C group, the AB and NLC groups had the lowest percentage of PMN, followed by those in the FLC group (p < 0.05). All treated buffaloes had significantly lower numbers of pathogens than the control buffaloes. Compared to control, all treatments significantly down-regulated endometrial proinflammatory encoding mRNA expression. The concentrations of IL1B, TNFAIP7, and leukocyte esterase activity in the uterine washings were significantly decreased in the AB and NLC groups compared to the C and FLC groups. All treatments significantly decreased concentrations of serum proinflammatory cytokines compared to control. Both the AB and NLC groups had significantly lower concentrations of serum NEFA than the C and FLC groups. The percentage of control buffaloes having an echogenic uterus and PVD score > 2 was significantly higher than those in the treated buffaloes with higher numbers of corpora lutea, higher conception rates, and shorter days open than control buffaloes (p < 0.05). In conclusion, L. lactis-producing antimicrobial and anti-inflammatory metabolites reduce uterine inflammatory responses and improve fertility in buffaloes.

Spectroscopic Investigations of Porphyrin-TiO2 Nanoparticles Complexes

This study presents the spectral characterization of TiO₂ nanoparticles (NPs) functionalized with three porphyrin derivatives: 5,10,15,20-(Tetra-4-aminophenyl) porphyrin (TAPP), 5,10,15,20-(Tetra-4-methoxyphenyl) porphyrin (TMPP), and 5,10,15,20-(Tetra-4-carboxyphenyl) porphyrin (TCPP). UV-Vis absorption and Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR) spectroscopic studies of these porphyrins and their complexes with TiO₂ NPs were performed. In addition, the efficiency of singlet oxygen generation, the key species in photodynamic therapy, was investigated. UV-Vis absorption spectra of the NPs complexes showed the characteristic bands of porphyrins. These allowed us to determine the loaded porphyrins on TiO₂ NPs functionalized with porphyrins. FTIR-ATR revealed the formation of porphyrin-TiO₂ complexes, suggesting that porphyrin adsorption on TiO₂ may involve the pyrroles in the porphyrin ring, or the radicals of the porphyrin derivative. The quantum yield for singlet oxygen generation by the studied porphyrin complexes with TiO₂ was higher compared to bare porphyrins for TAPP and TMPP, while for the TCPP-TiO₂ NPs complex, a decrease was observed, but still maintained a good efficiency. The TiO₂ NPs conjugates can be promising candidates to be tested in photodynamic therapy in vitro assays.

Nanoformulation of Tetrapyrroles Derivatives in Photodynamic Therapy: A Focus on Bacteriochlorin

Photodynamic therapy (PDT) is a well-known remedial treatment for cancer, infections, and various other diseases. PDT uses nontoxic dyes called photosensitizers (PS) that are activated in visible light at the proper wavelength to generate ROS (reactive oxygen species) that aid in killing tumor cells and destroying pathogenic microbes. Deciding a suitable photosensitizer is essential for enhancing the effectiveness of photodynamic therapy. It is challenging to choose the photosensitizer that is appropriate for specific pathological circumstances, such as different cancer species. Porphyrin, chlorin, and bacteriochlorin are tetrapyrroles used with proper functionalization in PDT, among which some compound has been clinically approved. Most photosensitizers are hydrophobic, have minimum solubility, and exhibit cytotoxicity due to the dispersion in biological fluid. This paper reviewed some nanotechnology-based strategies to overcome these drawbacks. In PDT, metal nanoparticles are widely used due to their enhanced surface plasmon resonance. The self-assembled nano-drug carriers like polymeric micelles, liposomes, and metal-based nanoparticles play a significant role in solubilizing the photosensitizer to make them biocompatible.

Photophysical characterization and in vitro anti-leishmanial effect of 5,10,15,20-tetrakis(4-fluorophenyl) porphyrin and the metal (Zn(II), Sn(IV), Mn(III) and V(IV)) derivatives

In this report 5 compounds were synthesized and structural and their photophysical characterization was performed (Φ_Δ and Φ_f). Furthermore, in this in vitro study, their biological activity against Leishmania panamensis was evaluated. The photophysical behavior of these compounds was measured and high Φ_Δ and low Φ_f was observed. Besides, DFT quantum calculations on the electronic structures were performed. Finally, the biological activity was determined by means of the compounds capacity to inhibit the viability of parasites using the MTT assay. The inclusion of the metal ions substantially modified the photophysical and biological properties in comparison with the free metal porphyrin (1). In fact, Zn²⁺ porphyrin derivative (2) showed a marked decrease of Φ_f and increase of Φ_Δ. In this sense, using TDDFT approaches, a luminescent process for Sn⁴⁺ derivative (3) was described, where emissive states involve the ML-LCT transition. So, this led to a decrease in the singlet oxygen production (0.82-0.67). Biological results showed that all compounds inhibit the viability of L. panamensis with high efficiency; the decrease in the viability was greater as the concentration of exposure increased. Finally, under light irradiation the IC₅₀ of L. panamensis against the Zn(II)-porphyrin (2) and V(IV)-porphyrin (5) was lower than the IC₅₀ of the Glucantime control (IC₅₀ = 2.2 and 6.95 μM Vs IC₅₀ = 12.7 μM, respectively). We showed that the use of porphyrin and metalloporphyrin-type photosensitizers with exceptional photophysical properties can be successful in photodynamic therapy (PDT) against L. panamensis, being the diamagnetic ion Zn²⁺ a candidate for the preparation of metalloporphyrins with high singlet oxygen production.

Photophysical study and in vitro approach against Leishmania panamensis of dicloro-5,10,15,20-tetrakis(4-bromophenyl)porphyrinato Sn(IV)

Background: Photodynamic therapy activity against different biological systems has been reported for porphyrins. Porphyrin modifications through peripheral groups and/or by metal insertion inside the ring are main alternatives for the improvement of its photo-physical properties. In this study, we synthesized and characterized 5,10,15,20-tetrakis(4-bromophenyl)porphyrin and the dicloro-5,10,15,20-tetrakis(4-bromophenyl)porphyrinato Sn(IV).

Methods: Metal-free porphyrin was synthesized using the Alder method, while the Sn(IV)-porphyrin complex was prepared by combining metal-free porphyrin with stannous chloride in DMF; the reaction yields were 47% and 64% respectively. Metal-free porphyrin was characterized by UV-Vis, FT-IR, ESI-mass spectrometry and ¹³C-NMR. Additionally, the Sn(IV) -porphyrin complex was characterized using UV-Vis and FT-IR. Cyclic voltammetry tests in four different solvents. The fluorescence quantum yield (Φ _f) was measured using fluorescein as a standard, the singlet oxygen quantum yield (Φ _D) was estimated using the standard 5,10,15,20-(tetraphenyl)porphyrin (H2TPP) and the quencher of singlet oxygen 1,3-diphenylisobenzofuran (DPBF).

Results: UV-Vis assay showed typical Q and Soret bands for porphyrin and its metallo-porphyrin complex. Compounds showed photoluminescence at the visible range of electromagnetic spectrum. The inclusion of the metal in the porphyrin core changed the Φ _f from 0.15 to 0.05 and the Φ _D increased from 0.55 to 0.59. Finally, the effect of the compounds on the viability of L. panamensis was evaluated by means of the MTT test. The results showed that both compounds decreased the viability of the parasite; this inhibitory activity was greater under light irradiation; the porphyrin compound had IC ₅₀ of 16.5 μM and the Sn(IV)-porphyrin complex had IC ₅₀ of 19.2 μM.

Conclusion: The compounds were synthesized efficiently, their characterization was carried out by different spectroscopy techniques and their own signals were evidenced for both structures, both compounds decreased the cell viability of L. panamensis.

Antimicrobial Photodynamic Therapy: Latest Developments with a Focus on Combinatory Strategies

Antimicrobial photodynamic therapy (aPDT) has become a fundamental tool in modern therapeutics, notably due to the expanding versatility of photosensitizers (PSs) and the numerous possibilities to combine aPDT with other antimicrobial treatments to combat localized infections. After revisiting the basic principles of aPDT, this review first highlights the current state of the art of curative or preventive aPDT applications with relevant clinical trials. In addition, the most recent developments in photochemistry and photophysics as well as advanced carrier systems in the context of aPDT are provided, with a focus on the latest generations of efficient and versatile PSs and the progress towards hybrid-multicomponent systems. In particular, deeper insight into combinatory aPDT approaches is afforded, involving non-radiative or other light-based modalities. Selected aPDT perspectives are outlined, pointing out new strategies to target and treat microorganisms. Finally, the review works out the evolution of the conceptually simple PDT methodology towards a much more sophisticated, integrated, and innovative technology as an important element of potent antimicrobial strategies.

Porphyrin Derivative Nanoformulations for Therapy and Antiparasitic Agents

Porphyrins and analogous macrocycles exhibit interesting photochemical, catalytic, and luminescence properties demonstrating high potential in the treatment of several diseases. Among them can be highlighted the possibility of application in photodynamic therapy and antimicrobial/antiparasitic PDT, for example, of malaria parasite. However, the low efficiency generally associated with their low solubility in water and bioavailability have precluded biomedical applications. Nanotechnology can provide efficient strategies to enhance bioavailability and incorporate targeted delivery properties to conventional pharmaceuticals, enhancing the effectiveness and reducing the toxicity, thus improving the adhesion to the treatment. In this way, those limitations can be overcome by using two main strategies: (1) Incorporation of hydrophilic substituents into the macrocycle ring while controlling the interaction with biological systems and (2) by including them in nanocarriers and delivery nanosystems. This review will focus on antiparasitic drugs based on porphyrin derivatives developed according to these two strategies, considering their vast and increasing applications befitting the multiple roles of these compounds in nature.

Recent Advances in the Discovery of Novel Antiprotozoal Agents

Parasitic diseases have serious health, social, and economic impacts, especially in the tropical regions of the world. Diseases caused by protozoan parasites are responsible for considerable mortality and morbidity, affecting more than 500 million people worldwide. Globally, the burden of protozoan diseases is increasing and is been exacerbated because of a lack of effective medication due to the drug resistance and toxicity of current antiprotozoal agents. These limitations have prompted many researchers to search for new drugs against protozoan parasites. In this review, we have compiled the latest information (2012-2017) on the structures and pharmacological activities of newly developed organic compounds against five major protozoan diseases, giardiasis, leishmaniasis, malaria, trichomoniasis, and trypanosomiasis, with the aim of showing recent advances in the discovery of new antiprotozoal drugs.

Preparation and biological evaluation of a carrier free 90yttrium labelled porphyrin as a possible agent for targeted therapy of tumor

In this research article, 5,10,15,20-tetrakis(phenyl)porphyrin (H2TPP) was produced and characterized. Then, radiolabeling of H2TPP was performed using the carrier free Y-90 which was prepared by the use of a home-made yttrium imprinted sorbent. The radiolabeling procedure was accomplished at 60 [Formula: see text] C during 12 h with a suitable radiochemical purity (95 ± 2% ITLC, 99 ± 0.5% HPLC) and specific activity of (1.0 ± 0.1 GBq/mmol). The obtained radio-labeled H2TPP in final formulation was kept for a week in order to investigate the complex stability. Accordingly, the partition coefficient was calculated as log [Formula: see text] 2.05. Furthermore, the biodistribution of the [Formula: see text]Y–TPP was determined in vital organs of normal wild-type rats using scarification studies. The kidneys could mostly remove the radio-complexes from the blood circulation and in less extends from the liver. As a result it is expected that due to its lipophilicity the higher mitochondrial and thus, tumor cell uptake of this radiolabeled porphyrin happens and therefore [Formula: see text]Y–TPP could act as an efficient potential agent for targeted therapy of tumor.

Synthesis, antinociceptive and anti-inflammatory effects of porphyrins

Porphyrins are natural compounds with several biological activities. We report the synthesis and the evaluation of the anti-inflammatory and antinociceptive effects of 4 porphyrins: 5,10,15,20-tetraphenylporphyrin (TPP), 5,10,15,20-tetra(4'-fluorophenyl)porphyrin (TpFPP), 5,10,15,20-tetra(4'-chlorophenyl)porphyrin (TpClPP), and 5,10,15,20-tetra(4'-bromophenyl)porphyrin (TpBrPP). The in vitro anti-inflammatory effects were evaluated on heat-induced hemolysis. The antinociceptive effects were evaluated using the hot plate and formalin tests. The in vivo anti-inflammatory assays were tested on the acute and chronic TPA (12-O-tetradecanoylphorbol 13-acetate) method to induce ear edema. The anti-arthritic effects were evaluated using carrageenan kaolin induced arthritis (CKIA). All porphyrins inhibited hemolysis with similar potency than naproxen (NPX). In the antinociceptive tests, all porphyrins tested at 200mg/kg showed similar effects compared to 100mg/kg NPX. In the in vivo anti-inflammatory acute assay, only three porphyrins (TPP, TpFPP and TpBrPP) decreased inflammation with similar activity than 2mg/ear indomethacin (IND). Further anti-inflammatory experiments were carried out with TPP, TpFPP and TpBrPP. In the in vivo anti-inflammatory chronic assay, porphyrins decreased inflammation with similar activity than 8mg/kg IND. Porphyrins tested at 200mg/kg showed anti-arthritic effects. The antinociceptive, anti-inflammatory and arthritic activities of porphyrins suggest that these compounds might be a good alternative for the treatment of inflammatory diseases.