Antiproliferative and antiapoptotic effect of thymoquinone on cancer cells in vitro.

OBJECTIVES: Nigella sativa oil and thymoquinone were comparatively tested in vitro for their effects on human cancer cell lines (glioma,T98; prostate, LnCaP) as well as mouse embryonic fibroblast cell lines (3T3), and for the induction of apoptosis. METHODS: Individual cell lines were treated with thymoquinone and N. sativa oil for 24 and 48 hr. Survival rate with MTT, apoptosis with flow cytometry and caspase-9 mRNA enzyme levels with RT-PCR were determined in vitro. RESULTS: Application of respective concentrations of N. sativa oil (excluding 100 µg/mL for 48 hr) did not change the number of tested cell lines, however, treatment with thymoquinone reduced the number of all cells significantly. Thymoquinone also exerted its apoptosis inducing effect through the activation of caspase-9. CONCLUSION: Differing with the type of cancer cells, thymoquinone posseses a strong contentration and time dependent survival reducing effect on cancer cells via apoptosis (Fig. 6, Ref. 22). Text in PDF www.elis.sk.

The effect of leptin and resveratrol on JAK/STAT pathways and Sirt-1 gene expression in the renal tissue of ischemia/reperfusion induced rats.

OBJECTIVE: Our study aimed to investigate the possible modifying effects of leptin and combined use of resveratrol on rat renal I/R injury and their relationship on signal pathways and apoptosis-related mechanisms. BACKGROUND: Renal ischemia-reperfusion (I/R) injury is an important cause of acute renal failure. METHODS: Male Sprague Dawley rats were divided into 5 groups: Control, I/R, I/R+leptin, I/R+resveratrol and I/R+leptin+resveratrol. Leptin (10 µg/kg BW) was administered (i.p.) 30 min prior to I/R. Resveratrol was administered by gavage at 20 mg/kg BW per d for 12 d prior to I/R. The left renal artery was exposed to 1 h of ischemia and 1 h of reperfusion. RESULTS: Resveratrol treatment alone increased TNF-α, TNF-α R1, NF-κB, SIRT-1, STAT1 and STAT3 mRNA levels and decreased caspase 3 protein levels. Leptin treatment alone significantly decreased the caspase 3 protein levels. The combined use of resveratrol and leptin significantly increased STAT3, and caspase 3 mRNA levels, and decreased the caspase 3 protein levels. Apoptosis was significantly decreased especially in the leptin and leptin+resveratrol groups. CONCLUSION: The present study suggest that a combined use of resveratrol and leptin has preventive and regulatory effects on renal I/R injury; the mechanism involves decreasing apoptosis, likely by altering the JAK/STAT pathway and SIRT1 expression (Fig. 8, Ref. 24).

Effects of ceranib-2 on cell survival and TNF-alpha in colon cancer cell line.

OBJECTIVE: The aim of this study was to investigate the effects of a novel anti-cancer drug, ceranib-2, which targets the acid ceramidase, in human colon cancer cell line. MATERIALS AND METHODS: The cell lines were treated with 50 µM of ceranib-2. Relative mRNA expression of TNF-alpha, TNF-R1 and ASAH were assessed by quantitative RT-PCR. RESULTS: Ceranib-2 reduced cell viability in a dose-dependent manner and the apoptotic values of cells following treatment with the dose of 50 µM were reduced significantly both at 24 h and 48 h compared to the control cells (p < 0.001). TNF-alpha receptor 1 (TNF-R1) mRNA levels were reduced significantly in the cell lines treated with both 25 µM and 50 µM of ceranib-2 for 24 h compared to the control cells (p < 0.05), whereas the difference between the treatment and the control cell lines diminished at 48 h. The human acid ceramidase gene (ASAH) mRNA levels were significantly higher in the cell lines treated with 50 µM of ceranib-2 for 48 h than in the other cell lines (p < 0.001). CONCLUSION: The study shows that ceranib-2 increased apoptosis by inducing ASAH expression and reduced TNF-R1 expression in human colon cancer cell lines in a dose and time-dependent manner (Fig. 3, Ref. 17).

Leptin receptor (Ob-R) mRNA expression and serum leptin concentration in patients with colorectal and metastatic colorectal cancer.

The objective of the present study was to investigate the effect of leptin on the progression of colorectal carcinoma to metastatic disease by analyzing the serum leptin concentration and Ob-R gene expression in colon cancer tissues. Tissue samples were obtained from 31 patients who underwent surgical resection for colon (18 cases) and metastatic colon (13 cases) cancer. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA) and Ob-R mRNA expression by real-time polymerase chain reaction (RT-PCR) for both groups. ELISA data were analyzed by the Student t-test and RT-PCR data were analyzed by the Mann-Whitney U-test. RT-PCR results demonstrated that mRNA expression of Ob-R in human metastatic colorectal cancer was higher than in local colorectal cancer tissues. On the other hand, mean serum leptin concentration was significantly higher in local colorectal cancer patients compared to patients with metastatic colorectal cancer. The results of the present study suggest a role for leptin in the progression of colon cancer to metastatic disease without weight loss. In other words, significantly increased Ob-R mRNA expression and decreased serum leptin concentration in patients with metastatic colon cancer indicate that sensitization to leptin activity may be a major indicator of metastasis to the colon tissue and the determination of leptin concentration and leptin gene expression may be used to aid the diagnosis.

Leptin receptor (Ob-R) mRNA expression and serum leptin concentration in patients with colorectal and metastatic colorectal cancer

The objective of the present study was to investigate the effect of leptin on the progression of colorectal carcinoma to metastatic disease by analyzing the serum leptin concentration and Ob-R gene expression in colon cancer tissues. Tissue samples were obtained from 31 patients who underwent surgical resection for colon (18 cases) and metastatic colon (13 cases) cancer. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA) and Ob-R mRNA expression by real-time polymerase chain reaction (RT-PCR) for both groups. ELISA data were analyzed by the Student t-test and RT-PCR data were analyzed by the Mann-Whitney U-test. RT-PCR results demonstrated that mRNA expression of Ob-R in human metastatic colorectal cancer was higher than in local colorectal cancer tissues. On the other hand, mean serum leptin concentration was significantly higher in local colorectal cancer patients compared to patients with metastatic colorectal cancer. The results of the present study suggest a role for leptin in the progression of colon cancer to metastatic disease without weight loss. In other words, significantly increased Ob-R mRNA expression and decreased serum leptin concentration in patients with metastatic colon cancer indicate that sensitization to leptin activity may be a major indicator of metastasis to the colon tissue and the determination of leptin concentration and leptin gene expression may be used to aid the diagnosis.

The effects of PDE5 inhibitory drugs on renal ischemia/reperfusion injury in rats.

The aim of the present study was to evaluate the effects of phosphodiesterase type 5 (PDE5) inhibitory drugs, Tadalafil and Sildenafil, on inducible NOS (iNOS), endothelial NOS (eNOS) and p53 genes expressions and apoptosis in ischemia/reperfusion (I/R) induced oxidative injury in rat renal tissue. Eighty Sprague-Dawley rats (300-350 g) were divided into four groups. In ischemia/reperfusion group, rats were subjected to renal ischemia by clamping the left pedicle for 60 min, and then reperfused for 90 min. On the other hand, in other two groups the rats were individually pretreated with Tadalafil and Sildenafil 1 h before the induction of ischemia. Malondialdehyde (MDA) is determined in renal tissue homogenates by high-performance liquid chromatography, the number of apoptotic cell were calculated by TUNEL method and p53 and eNOS expression were detected with immunohistochemistry. On the other hand, myeloperoxidase (MPO) levels were measured by spectrophotometric method and the mRNA level of iNOS in renal tissue was determined by Real-time PCR (RT-PCR). Our results indicate that MDA and MPO levels were increased in the I/R group than those in the control group. Both Tadalafil and Sildenafil treatment decreased the MDA levels in ischemia/reperfusion group, whereas this effect was more potent with Sildenafil. RT-PCR results showed that, iNOS gen expression increased in the I/R group, but decreased in the PDE5 inhibitory drugs treated group. Apoptotic cells, eNOS levels and p53 positive cells were also decreased in PDE5 inhibitory drugs treated group. We suggest that Tadalafil and Sildenafil have beneficial effects against I/R related renal tissue injury and this protective effect is clearer for Sildenafil than Tadalafil.