Synthesis of some novel pyridine compounds containing bis‐1,2,4‐triazole/thiosemicarbazide moiety and investigation of their antioxidant properties,carbonic anhydrase,and acetylcholinesterase enzymes inhibition profiles

Some novel derivatives of thiosemicarbazide and 1,2,4‐triazole‐3‐thiol were synthesized and evaluated for their biological activities. The title compounds were prepared starting from readily available pyridine‐2,5‐dicarboxylic acid. The reaction carboxylic acid with absolute ethanol afforded the corresponding dimethyl pyridine‐2,5‐dicarboxylate ( 1 ). The reaction of dimethyl‐2,5‐pyridinedicarboxylate ( 1 ) with hydrazine hydrate good yielded pyridine‐2,5‐dicarbohydrazide ( 2 ). Refluxing compound 2 with alkyl/aryl isothiocyanate derivatives for 3–8 h afforded 1,4‐disubstituted thiosemicarbazides ( 3a–e ). Base‐catalyzed intra‐molecular dehydrative cyclization of these intermediates furnished the 4,5‐disubstituted bis‐mercaptotriazoles ( 4a–e ) in good yield (85%–95%). Among the target compounds, 2,2′‐(pyridine‐2,5‐diyldicarbonyl)bis[N‐(p‐methoxyphenyl)hydrazinecarbothioamide] ( 3c ) showed very high activity with value of 72.93% against 1,1‐diphenyl‐2‐picrylhydrazyl free radical at the concentration of 25 μg/mL. The inhibitory effects of the target compounds against acetylcholinesterase (AChE), hCA I, and II were studied. AChE, cytosolic hCA I and II isoforms were potently inhibited by synthesized these derivatives with K_is in the range of 3.07 ± 0.76–87.26 ± 29.25 nM against AChE, in the range of 1.47 ± 0.37–10.06 ± 2.96 nM against hCA I, and in the range of 3.55 ± 0.57–7.66 ± 2.06 nM against hCA II, respectively.     

In vitro cytotoxic and in vivo antitumoral activities of some aminomethyl derivatives of 2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thiones—Evaluation of their acetylcholinesterase and carbonic anhydrase enzymes inhibition profiles

The 1,2,4‐triazole and its derivatives were reported to exhibit various pharmacological activities such as antimicrobial, analgesic, anti‐inflammatory, antitumoural, cytotoxic, and antioxidant properties. In this study, a series of triazole compounds (M1‐M10) were evaluated for some biological activities. In vitro qualifications of these compounds on acetylcholinesterase (AChE) and human carbonic anhydrase enzyme activities were performed. Also, their antitumoral activities in human colon cancer (HT29) cell line cultures were examined. In addition, colon cancer experimentation was induced in rats by an in vivo method, and the in vivo anticancer effects of triazole derivatives were investigated. Also, the effects of these derivatives in levels of antioxidant vitamin A, vitamin E, and MDA were studied in rat liver and blood samples. Most of the compounds were found to exhibit significant antioxidant and antitumoral activities. All the compounds had cytotoxic activities on HT29 cell lines with their IC₅₀ values lower than 10 µM concentrations. The low IC ₅₀ values of the compounds are M1 (3.88 µM), M2 (2.18 µM), M3 (4.2 µM), M4 (2.58 µM), M5 (2.88 µM), M6 (2.37 µM), M7 (3.49 µM), M8 (4.01 µM), M9 (8.90 µM), and M10 (3.12 µM).     

Plasma manganese, selenium, zinc, copper, and iron concentrations in patients with schizophrenia

A number of essential trace elements play a major role in various metabolic pathways. Selenium (Se), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) are essential trace elements that have been studied in many diseases, including autoimmune, neurological, and psychiatric disorders. However, the findings of previous research on the status of trace elements in patients with schizophrenia have been controversial. We studied these elements in patients with a DSM-IV diagnosis of schizophrenia and compared them with sex- and age-matched healthy controls. Plasma Cu concentrations were significantly higher (p<0.01) and Mn and Fe concentrations were lower (p<0.05 and p<0.05, respectively) in schizophrenic patients than in controls. Se and Zn concentrations and protein levels did not differ between patients and healthy controls. These observations suggest that alterations in essential trace elements Mn, Cu, and Fe may play a role in the pathogenesis of schizophrenia. However, findings from trace element levels in schizophrenia show a variety of results that are difficult to interpret.     

Alterations of serum selenium, zinc, copper, and iron concentrations and some related antioxidant enzyme activities in patients with cutaneous leishmaniasis

The aim of this study was to measure the alterations in serum selenium (Se), copper (Cu), zinc (Zn), and iron (Fe) concentrations and their carrier proteins, ceruloplasmin (Cp), transferrin (Tf) albumin, and related antioxidant enzyme activities, erythrocyte Cu-Zn Superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities in patients with cutaneous leishmaniasis (CL). Erythrocyte Cu-Zn SOD activities, serum Cu concentrations, and Cp levels were found to be significantly higher in the patients group than those of controls. However, GSH-Px and CAT activities and Se, Zn, Fe, and Tf levels were lower in patients than in the control subjects. There were positive important correlation’s between Cu-Zn SOD and Cp, Cu-Zn SOD and Cu, Cp and Cu, GSH-Px and Se, and Fe and CAT in the patients group. Our results showed that serum essential trace elements Se, Zn, Cu, and Fe concentrations and their related enzymes Cu-Zn SOD, GSH-Px, and CAT activities change in CL patients. The changes may be a part of defense strategies of organism and are induced by the hormonelike substances.     

Relationship between DNA damage, total antioxidant capacity and coronary artery disease

OBJECTIVE: It has been known that there was a relation between the levels of DNA damage and the severity of the coronary artery disease (CAD). However, little is known about association of DNA damage with total antioxidant capacity (TAC) and CAD. The aim of this study is to evaluate the relationship between DNA damage, TAC and CAD. METHODS: We used the comet assay to measure DNA damage from 53 patients with angiographically documented CAD and 42 patients with angiographically documented normal coronary vessel. The extent and severity of CAD was calculated to Gensini score index. TAC of plasma was determined using a novel automated measurement method. RESULTS: Mean values of DNA damage were significantly higher in CAD patients than in the control group (p<0.001). There was a positive correlation between Gensini score index and DNA damage (r=0.590, p<0.001). Additionally, significantly positive correlations between score of DNA damage, and diabetes, smoking, obesity and hyperlipidemia were found (p<0.05). There was also a negative correlation between TAC and DNA damage (r=-0.711, p<0.001). The DNA damage was significantly higher in diabetic, smoker, hyperlipidemic and obese individuals than those without these conditions (p=0.001, p=0.006, p=0.001, p=0.004, respectively). CONCLUSIONS: These data indicate that the level of DNA damage is increased and TAC level is decreased in CAD. DNA damage is correlated with the severity of the CAD, and levels of TAC.     

Increased DNA damage in patients with complete hydatidiform mole

The pathologic mechanisms underlying the gestational trophoblastic diseases are largely unexplored, but are thought to involve oxidative damage to the maternal vasculature and also to the placenta. In this study we have assessed the plasma levels of total antioxidant response (TAR) and the levels of endogenous DNA damage--determined by the comet assay--in peripheral blood lymphocytes from 13 women with complete hydatidiform mole (CHM) and compared these with those of 12 healthy pregnant controls and 10 healthy non-pregnant controls. Significantly lower mean levels of plasma TAR were found in patients with CHM compared with healthy pregnant controls (1.08+/-0.29 versus 1.17+/-0.14 mmol Trolox Eq/L, p<0.05) and with healthy non-pregnant controls (1.08+/-0.29 versus 1.38+/-0.12 mmol Trolox Eq/L, p<0.05). Significantly higher mean levels of endogenous DNA damage were observed in patients with CHM than in healthy pregnant controls (234.5+/-50.74 versus 125.7+/-45.4 AU, p<0.05) or in healthy non-pregnant controls (234.5+/-50.74 versus 104.0+/-49.6 AU, p<0.05). We observed an inverse correlation between the plasma TAR and the levels of endogenous DNA damage (r=-0.64, p<0.01), in that the levels of oxidative damage to the DNA were found to parallel the decrease in the plasma TAR in the CHM group. These results reveal a relationship between the extracellular and intracellular (as reflected by damage to the DNA) levels of oxidation. Our observations suggest that there is a link between the increased levels of oxidative stress and the increase in endogenous DNA damage seen in patients with CHM, as compared with those seen in normal pregnancy. However, the nature of this link, and whether it is direct or indirect, remains to be explored.     

Increased lymphocyte deoxyribonucleic acid damage in patients with cardiac syndrome X

OBJECTIVES: To investigate whether there is lymphocyte deoxyribonucleic acid (DNA) damage in patients with cardiac syndrome X (CSX), and its relation with total antioxidant status (TAS), inflammation and ischemia. METHODS: Twenty-three patients with CSX, 21 patients with non-CSX (NCSX) and 20 healthy volunteers were included in the study. Lymphocyte DNA damage (Arbitrary Unit) was assessed by alkaline single cell electrophoresis (comet) assay in peripheral lymphocyte, and plasma levels of TAS (mmol Trolox equiv./l) were determined using a novel automated measurement method. High sensitive C-reactive protein (hsCRP) and other biochemical parameters were measured from all subjects. Treadmill exercise test and coronary angiography were performed to CSX and NCSX groups. RESULTS: Lymphocyte DNA damage was increased in patients with CSX compared with NCSX and control group (p<0.001, for both). Also, TAS was decreased, and hsCRP was increased in CSX compared with NCSX and control group (p<0.001, for all). Lymphocyte DNA damage was correlated with magnitude of ST depression (p=0.034), hsCRP (p=0.001), TAS (p<0.001) and presence of diabetes (p=0.022) in bivariate analysis. In multiple linear regression analysis, lymphocyte DNA damage was correlated with only TAS (beta=-0.413, p=0.017) and hsCRP (beta=0.414, p=0.006). CONCLUSION: Lymphocyte DNA damage was increased in patients with CSX. The increase in lymphocyte DNA damage may be related with increased oxidative stress and inflammation in patients with CSX.     

Lymphocyte DNA damage and oxidative stress in patients with iron deficiency anemia

Oxidant stress has been shown to play an important role in the pathogenesis of iron deficiency anemia. The aim of this study was to investigate the association between lymphocyte DNA damage, total antioxidant capacity and the degree of anemia in patients with iron deficiency anemia. Twenty-two female with iron deficiency anemia and 22 healthy females were enrolled in the study. Peripheral DNA damage was assessed using alkaline comet assay and plasma total antioxidant capacity was determined using an automated measurement method. Lymphocyte DNA damage of patients with iron deficiency anemia was significantly higher than controls (p<0.05), while total antioxidant capacity was significantly lower (p<0.001). While there was a positive correlation between total antioxidant capacity and hemoglobin levels (r=0.706, p<0.001), both total antioxidant capacity and hemoglobin levels were negatively correlated with DNA damage (r=-0.330, p<0.05 and r=-0.323, p<0.05, respectively). In conclusion, both oxidative stress and DNA damage are increased in IDA patients. Increased oxidative stress seems as an important factor that inducing DNA damage in those IDA patients. The relationships of oxidative stress and DNA damage with the severity of anemia suggest that both oxidative stress and DNA damage may, in part, have a role in the pathogenesis of IDA.     

Investigation of acetylcholinesterase and mammalian DNA topoisomerases,carbonic anhydrase inhibition profiles,and cytotoxic activity of novel bis(α‐aminoalkyl)phosphinic acid derivatives against human breast cancer

The aim of this study was to evaluate biologically active novel molecules having potentials to be drugs by their antitumor properties and by activities of apoptotic caspase and topoisomerase. Following syntheses of novel eight bis(α‐aminoalkyl)phosphinic acid derivatives ( 4a–h ) as a result of array of reactions, compounds were evaluated by cytotoxic effects in vitro on human breast cancer (MCF‐7) and normal endothelial (HUVEC) cell lines. All phosphinic acid derivatives were effective for cytotoxicity on both MCF‐7 and HUVEC lines, while 4c , 4e , and 4f compounds were found significantly more effective. For the evaluation of antitumor properties of compounds in a highly sensitive method, their effects on inhibiting topoisomerases I and II were investigated. Also, some of the bis(α‐aminoalkyl)phosphinic acid derivatives ( 4a, 4e–h ) showed nice inhibitory action against acetylcholinesterase and human carbonic anhydrase isoforms I and II.     

Inhibitory effects of oxytocin and oxytocin receptor antagonist atosiban on the activities of carbonic anhydrase and acetylcholinesterase enzymes in the liver and kidney tissues of rats

The aim of this study was to investigate the effects of oxytocin (OT), atosiban, which is an OT receptor antagonist, and OT‐atosiban chemicals injected to rats on the activities of carbonic anhydrase (CA) and acetylcholinesterase (AChE) enzymes in liver and kidney tissues of rats. For this purpose, four different groups, each consisting of six rats (n = 6), were formed (control group, OT administered group, atosiban administered group, and both OT and atosiban administered group). The rats were necropsied 60 min after intraperitoneal injection of chemicals into the rats. Liver tissues of rats were extracted. CA and AChE enzyme activities were measured for each tissue by using hydratase, esterase, and acetylcholiniodide methods. Activity values for each enzyme obtained were statistically calculated.