Novel Sulfonamide-Based Analogs of Metformin Exert Promising Anti-Coagulant Effects without Compromising Glucose-Lowering Activity

Abstract

Metformin, one of the most frequently prescribed oral anti-diabetic drugs, is characterized by multidirectional activity, including lipid lowering, cardio-protective and anti-inflammatory properties. This study presents synthesis and stability studies of 10 novel sulfonamide-based derivatives of metformin with alkyl substituents in the aromatic ring. The potential of the synthesized compounds as glucose-lowering agents and their effects on selected parameters of plasma and vascular hemostasis were examined. Compounds with two or three methyl groups in the aromatic ring (6, 7, 9, 10) significantly increased glucose uptake in human umbilical vein endothelial cells (HUVECs), e.g., 15.8 µmol/L for comp. 6 at 0.3 µmol/mL versus 11.4 ± 0.7 µmol/L for control. Basic coagulation studies showed that all examined compounds inhibit intrinsic coagulation pathway and the process of fibrin polymerization stronger than the parent drug, metformin, which give evidence of their greater anti-coagulant properties. Importantly, synthesized compounds decrease the activity of factor X, a first member of common coagulation pathway, while metformin does not affect coagulation factor X (FX) activity. A multiparametric clot formation and lysis test (CL-test) revealed that the examined compounds significantly prolong the onset of clot formation; however, they do not affect the overall potential of clot formation and fibrinolysis. Erythrotoxicity studies confirmed that none of the synthesized compounds exert an adverse effect on erythrocyte integrity, do not contribute to the massive hemolysis and do not interact strongly with the erythrocyte membrane. In summary, chemical modification of metformin scaffold into benzenesulfonamides containing alkyl substituents leads to the formation of potential dual-action agents with comparable glucose-lowering properties and stronger anti-coagulant activity than the parent drug, metformin.

Incorporation of Sulfonamide Moiety into Biguanide Scaffold Results in Apoptosis Induction and Cell Cycle Arrest in MCF-7 Breast Cancer Cells

“…Another important issue is an effect of these novel compounds on the viability of primary cells. Previously, we performed a series of experiments using endothelial cells of human umbilical vein [ 29 ]. Reported IC 50 values were far lower than those presented for MCF-7 cells.…”

“…For instance, the IC 50 value of compound 8 was 490 ± 70.1 µmol/L, which is approximately 31-fold lower than in MCF-7 cells ( Table 3 ). The studied compounds were also examined towards interaction with red blood cell membrane [ 29 ]. All compounds were found to be hemocompatible since the hemolysis rate after incubation of RBCs with metformin derivatives ( 1 – 10 ) did not exceed 10% which is regarded as clinically important value.…”

“…In addition, the effects of compounds 1 – 10 on the morphology of erythrocytes were also carefully monitored. Previously conducted studies [ 29 ] showed a small interaction of the examined metformin analogues with the red blood cell membrane since mainly physiological transformation of discocytes into echinocytes and stomatocytes was observed. It means that compounds 1 – 10 do not disturb erythrocyte function.…”

“…The structure of the examined sulfonamide derivatives of metformin (compounds 1 – 10 ) are depicted in Table 1 . The chemical characterization and basic properties were described elsewhere [ 29 ]. The analyzed compounds 1 – 10 were also reported to be stable in 0.1 M NaOH and TBS buffer in the abovementioned study.…”

“…The analyses were conducted at room temperature (RT). The detailed procedure of chromatographic analysis was described in our previous paper [ 29 ]. The studies were performed in quadruplicates.…”