Immunosuppressive properties of amino acid and peptide derivatives of mycophenolic acid

New Meroterpenoids and α-Pyrone Derivatives Isolated from the Mangrove Endophytic Fungal Strain Aspergillus sp. GXNU-Y85

Two new meroterpenoids, aspergienynes O and P (1 and 2), one new natural compound, aspergienyne Q (3), and a new α-pyrone derivative named 3-(4-methoxy-2-oxo-2H-pyran-6-yl)butanoic acid (4) were isolated from the mangrove endophytic fungal strain Aspergillus sp. GXNU-Y85, along with five known compounds (5-9). The absolute configurations of those new isolates were confirmed through extensive analysis using spectroscopic data (HRESIMS, NMR, and ECD). The pharmacological study of the anti-proliferation activity indicated that isolates 5 and 9 displayed moderate inhibitory effects against HeLa and A549 cells, with the IC50 values ranging from 16.6 to 45.4 μM.

An electrochemical sensor based on CS-MWCNT and AuNPs for the detection of mycophenolic acid in plasma

For patients receiving organ transplants, monitoring the blood concentration of MPA can provide timely information on whether MPA has reached the effective therapeutic window to better function while reducing the incidence of rejection or adverse reactions. In this study, an electrochemical sensor for the detection of MPA was built using a nanocomposite made of CS-MWCNT and AuNPs. At the same time, the high performance liquid phase (HPLC) method for MPA was established and compared with this sensor. The surface morphology, structure, and roughness of the material on the electrode were characterized by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and atomic force microscopy (AFM). In addition, the electrochemical behavior of the modified electrode was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The standard curve was obtained in blank plasma, not pure buffer solution. The peak current was linearly related to the MPA concentration in the linear range of 0.001-0.1 mM with a detection limit of 0.05 μM and good anti-interference ability. Moreover, the sensor was employed with success for the determination of MPA in rat plasma with good recovery. The electrochemical sensor presented here is eco-friendly, and sensitive, and offers a great possibility for practical applicability.

Novel amides of mycophenolic acid and some heterocyclic derivatives as immunosuppressive agents

The group of 18 new amide derivatives of mycophenolic acid (MPA) and selected heterocyclic amines was synthesised as potential immunosuppressive agents functioning as inosine-5′-monophosphate dehydrogenase (IMPDH) uncompetitive inhibitors. The synthesis of 14 of them employed uronium-type activating system (TBTU/HOBt/DIPEA) while 4 of them concerned phosphonic acid anhydride method (T3P/Py) facilitating amides to be obtained in moderate to excellent yields without the need of phenolic group protection. Most of optimised protocols did not require complicated reaction work-ups, including chromatographic, solvent-consuming methods. The biological activity assay was performed on the T-Jurkat cell line and peripheral mononuclear blood cells (PBMCs) which are both dedicated for antiproliferative activity determination. Each of designed derivatives was characterised by reduced cytotoxicity and benzoxazole analogue (A2) revealed the most promising activity. Subsequently, an observed structure-activity relationship was discussed.

Anticancer Properties of Amino Acid and Peptide Derivatives of Mycophenolic Acid

BACKGROUND

Although Mycophenolic Acid (MPA) is applied as prodrugs in clinic as an immunosuppressant, it also possesses anticancer activity. MPA acts as Inosine-5'-Monophosphate Dehydrogenase (IMPDH) inhibitor, where the carboxylic group at the end of the side chain interacts with Ser 276 of the enzyme via hydrogen bonds. Therefore, MPA derivatives with other polar groups indicated high inhibition too. On the other hand, potent anticancer agents like dacarbazine and cisplatin give numerous side-effects.

OBJECTIVE

Based on the literature data, MPA derivatives should be explored towards anticancer properties. Conversion of the carboxylic group of MPA to amide could maintain antiproliferative activity. Therefore, we decided to investigate several amino acid and peptide derivatives of MPA against chosen cancer cell lines in vitro.

METHODS

Amides of MPA hold threonine and arginine amino acid unit. These amino acid derivatives were tested as L and D enantiomers and both in free acid and methyl esters forms. Additionally, MPA was modified with tuftsin or retro-tuftsin as biologically active peptides, which could act as a drug carrier.

RESULTS

Amino acid and peptide derivatives of MPA were investigated in vitro as potential anticancer agents on cell lines: Ab melanoma, A375 melanoma and SHSY5Y neuroblastoma. The activity of the tested compounds was compared to parent MPA and known chemotherapeutics: dacarbazine and cisplatin.

CONCLUSION

Amino acid moiety and the sequence of amino acids in the peptide part influenced observed activity. The most active amino acid MPA analogues occurred to be D and L-threonine derivatives as methyl esters, probably due to better cell membrane penetration.