Preparation of Curcumin Prodrugs and Their in Vitro Anti-tumor Activities

The curcumin prodrugs, which could be selectively activated in tumor cells, were prepared to establish a basis for the targeted chemotherapy for cancer. On the basis of the molecular structure of curcumin, the N-maleoyl-L-valine-curcumin （NVC）, N-maleoyl- glycine-curcumin （NGC） were chemically synthesized and identified by IR and NMR spectroscopy. After treatment with these two prodrugs for 6--24 h, the rates of growth inhibition on human bladder cancer EJ cells and renal tubular epithelial （HKC） cells were detected by MTT colorimetry. Our results showed that after the treatment with 20 μmol/L--40 μmol/L NVC and NGC for 6--24 h, the growth inhibitory effects on EJ cells were 6.71%-65.13 % （P〈0.05）, 10. 96 %-73.01 % （p〈0. 05）, respectively, in both dose- and time-dependent manners. When compared with the curcumin of same concentrations, the growth inhibitory effects of these two prodrugs on HKC cells were significantly decreased （P〈0.01）. It is concluded that activation of curcumin prodrugs via hydrolysis functions of cellular esterase could inhibit the growth activities of tumor cells, and reduce the side effects on normal diploid cells. This provided a novel strategy for further exploration of tumor targeted chemotherapeutic drugs.     

Growth-inhibitory Effects of Curcumin on Ovary Cancer Cells and Its Mechanisms

Sinceanti carcinogenicagentsalsobringabouttheapoptosisinnormalcellswhiletheyinduceapop tosisinneoplasmcells ,inrecent years ,efforthasbeendirectedatlookingforneweffectiveanti cancerdrugswithlowtoxicity .Curcuministhemajoractivecomponentofcurcuma ,whichisa…     

HDAC1 expression and effect of curcumin on proliferation of Raji cells

Summary Histone deacetylase (HDAC₁) has a high expression in many cancer cells and curcumin can inhibit the growth of cancer cells. This paper was designed to investigate the expression of HDAC₁ of Raji cells and the effect of curcumin on their proliferation and apoptosis. Raji cells were treated with 3. 125–50 μmol/L curcumin for 8–48 h and the growth inhibition rates of Raji cells were measured by MTT. The expression of HDAC₁ on Raji cells were examined by mRNA, Western blot at 24 h various concertrations (1.6–50 μmol/L). Curcumin could selectively inhibit the proliferation of Raji cells in a dose and time dependent manner, with the inhibition rate being 52.47%–82.18% (P<0.01). The up-regulation of HDAC₁ expression was observed within 24 h after the treatment with curcumin as shown by RT-PCR and Western blot. With the increase of concentration, the expression was down-regulated in a dose dependent manner. It is concluded that the expression of HDAC₁ plays an important role in the proliferation and apoptosis of Raji cells and curcumin can inhibit the growth of Raji cells at various concentrations and promote the apoptosis of Raji cells. WU Qing, female, born in 1970, M. D., Ph. D. This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30271672).     

Inhibitory Effect of Curcumin on Proliferation of Human Pterygium Fibroblasts

In order to investigate the effect of curcumin on proliferation and apoptosis of human pterygium fibroblasts (HPF) in culture and search for a new method to prevent the recurrence after pterygium surgery, HPF was incubated with 0-160 μmol/L curcumin for 24-96 h. The MTT method was used to assay the biologic activities of curcumin at different time points and different doses. The expression of proliferating cell nuclear antigen (PCNA) in each group was detected by immunohistochemistry. The cell cycle distribution was detected by flow cytometry (FCM). Admini- stration of 20-80 μmol/L curcumin for 24-72 h could significantly inhibit HPF proliferation in a dose- and time-dependent manner (P<0.05). After treatment with curcumin at different concentrations of 20, 40, 80 and 160 μmol/L for 24 h, FCM revealed there was a significant sub-G1 peak at each concentration. The number of HPF in G0/G1 phase was increased, while in S phase, it was decreased (P<0.05). At the concentration of 20-80 μmol/L, curcumin, in a dose-dependent manner (P<0.05), could inhibit the expression of PCNA in HPF. It was suggesterd that curcumin could significantly in- hibit the proliferation of HPF, make HPF arrest in G0/G1 phase and induce the apoptosis of HPF in a dose- and time-dependent manner.     

Effects of concurrent use of rh-IFN-γ and curcumin on the antiproliferative capacity of HL-60 cells

Summary To understand the effect of rh-IFN-γ on the ability of curcumin to kill HL-60 cellsin vitro, the myeloid leukemic cell line HL-60 was studied by using cell culture. BrdU incorporation rate was examined by SABC, DNA content was determined by flow cytometry and apoptotic cell percentage was determined by TUNEL method. The results showed that curcumin inhibited proliferation of leukemic cells in a dose-dependent manner. When HL-60 cells were treated with 25 μmol curcumin for 24 h, the proliferative inhibitory rate was 43. 75±2. 00 %. This effect could be enhanced obviously by IFN-γ, the combined proliferative inhibitory rate increased to over 80 %. The 5-BrdU incorportion rate and the distribution of DNA content indicated that curcumin could arrest cells in the G₁,/G₀ and G₂/M phase of cell cycle. At the same time, the sub-G₁ peak (apoptotic peak) appeared. After IFN-γ combined with curcumin DNA synthesis rate decreased further. It showed a significant difference when compared with single drug group (P < 0. 05). Meanwhile, sub-Gi peak also increased. The percentage of TUNEL positive cells was aslo increased. It is concluded that IFN-γ can enhance the antiproliferative ability of curcumin against HL-60 cells.     

Growth inhibition and apoptosis inducing mechanisms of curcumin on human ovarian cancer cell line A2780

Curcumin,aphenolicpigmentextractedfrom curcuma,isthemajoreffectivecomponentofthat traditionalChinesemedicineandusedasadietarycoloringagentandanaturalcondiment.Recentre searchreportshaveshownthatcurcumincouldse lectivelyinhibittheproliferationandinducetheap optosisofmanytumorcells,buttheinvolvedmech anismsstillunclear(1,2).Thephenomenonthatcurcu mininducesapoptosisoftumorcellscouldbeseen innumerouscancers,however,theeffectsofcurcu minonhumanovariancancercellshavenotbeenre portedyet.Inthisresear…     

Effects of POH in Combination with STI571 on the Proliferation and Apoptosis of K562 Cells

Sofar ,the 2 phenylaminopyrimidineSTI5 71isthemostsuccessfulofthemolecularlydesignedATPcompetitorsfromNovartisPharma (Basel,Switzer land) ,whichspecificallyinhibitsAbltyrosinekinaseatmicromolarconcentrations .InhibitionoftheBcr Ablkinaseactivitybythiscom…     

Inhibitory effect of PPARγ agonist on the proliferation of human pterygium fibroblasts

The effects of DK2,a peroxisome proliferator-activated receptor γ agonist,on cultured human pterygium fibroblasts (HPFs) in virto were studied.The HPFs were incubated with 0-200 μmol/L DK2 for 12-72 h.The MTT method was used to assay the bio-activity of DK2 at different doses and time.The cytotoxic effect of DK2 was measured by LDH release assay.The cell cycle distribution and apoptosis were flow cytometrically detected.The expression of proliferating cell nuclear antigen (PCNA) in each group was detected by real-time PCR (RT-PCR) and Western blotting.The results showed that administration of 1-75 μmol/L DK2 for 12-72 h could significantly inhibit HPF proliferation in a dose-and time-dependent manner.DK2-treated cells did not release significant amount of LDH as compared with rosiglitazone-treated cells.After treatment with DK2 at concentrations of 15,25 μmol/L for 24 h,the number of HPFs in G 0 /G 1 phase was significantly increased while that in S phase was significantly decreased (P<0.05),leading to arrest at G 0 /G 1 phase.The apoptosis rates of HPF cells in drug-treated groups were significantly higher than the rate of control group (P<0.05).At the dosage range between 15-25 μmol/L,DK2 could inhibit the expression of PCNA mRNA and protein in HPFs in a dose-dependent fashion (P<0.05).It was concluded that PPARγ agonist can significantly inhibit HPF proliferation,resulting in the arrest at G 0 /G 1 phase,induce the apoptosis of HPFs,and suppress the synthesis of PCNA,in dose-and time-dependent manners.     

Effect of Diallyl Trisulfide on the Activation of T Cell and Macrophage－mediated Cytotoxicity

(冯作化)(张桂梅)(郝天玲)(周斌)(张慧)(姜志尧)ＥｆｆｅｃｔｏｆＤｉａｌｌｙｌＴｒｉｓｕｌｆｉｄｅｏｎｔｈｅＡｃｔｉｖａｔｉｏｎｏｆＴＣｅｌｌａｎｄＭａｃｒｏｐｈａｇｅ－ｍｅｄｉａｔｅｄＣｙｔｏｔｏｘｉｃｉｔｙ￥ＦＥＮＧＺｕｏ－ｈｕａ；ＺＨＡＮＧＧｕｉ－...     

Effect of Tiantai No.1 (天泰1号) on β-amyloid-induced neurotoxicity and NF-κ B and cAMP responsive element-binding protein

Objective： To investigate the effect and molecular mechanism of Tiantai No.1 （天泰1号）, a compound Chinese herbal preparation, for the prevention and reduction of neurotoxicity induced by betaamyloid peptides （Abeta） in vitro and its effects on nuclear factor-κB （NF-κB） and cAMP responsive element-binding protein （CREB） pathways using the gene transfection technique. Methods： B104 neuronal cells were used to examine the effects of Tiantai No.1 on lowering the neurotoxicity induced by Abeta. The cells were pre-treated with Tiantai No.1 at doses of 50, 100,150, or 200μg/mL respectively for 3 days and co-treated with Tiantai No.1 and beta-amyloid peptidel-40 （Aβ 1-40, 10 μmol/L） for 48 h or post-treated with Tiantai No.1 for 48 h after the cells were exposed to beta-amyloid peptides25-35 （Aβ 25-35） for 8 h. In gene transfection assays, cells were treated with Tiantai No.1 at 50 μg/mL and 150μg/mL for 5 days or co-treated with Tiantai No.1 and A 13 1-40 （5 μmo/L） for 3 days after electroporation for the evaluation of NF- κB and CREB expression. Results： Pre-treating and co-treating B104 neuronal cells with Tiantai No.1 lowered the neurotoxicity induced by Abeta, and post-treating with Tiantai No.1 reduced or blocked B104 neuronal apoptotic death induced by Abeta （P〈0.05, P〈0.01）. With a dose-dependent relationship, the same treatments increased the expression of NF-κB or CREB in B104 neuronal cells （P〈0.05, P〈0.01）. Meanwhile, Tiantai No.1 reduced Aβ-40 induced inhibition on NF-κB expression （P〈0.01）. Conclusions： Tiantai No.1 can protect neurons against the neurotoxicity induced by Abeta. The neuroprotective mechanisms may be associated with the activation of NF-κB and cAMP cellular signal pathways.     

The Effects of Nimesulide Combined with Cisplatin on Lung Cancer

To study the effects of cyclooxygenase 2 selective inhibitor Nimesulide (NIM) combined with Cisplatin (DDP) on human lung cancer and the possible mechanisms, the proliferation and ap-optosis of human lung cancer cell line A549 were evaluated by MTT reduction assay and flow cy-tometry respectively. The inhibitory effect on neoplasia in vivo was tested on nude mice subcutane-ously implanted tumor. Our results showed that NIM and DDP could inhibit A549 cell proliferation in a concentration-dependent pattern; this action was enhanced when NIM (25 /μmol/L) was given in combination with DDP and they worked in a synergistic or additive pattern as DDP concentration≥1 μg/ml. NIM and DDP could induce A549 cells apoptosis and the action was augmented when used in combination (P＜0.01). NIM and DDP could inhibit the growth of subcutaneously implan-ted tumors on nude mice (P＜0.05,P＜0.01) and the inhibitory rate of NIM combined with DDP was significantly higher than that of NIM or DDP group (P＜0.01, P＜0.01). It is concluded that combined use of NIM and DDP has significant synergistic antitumor effects on lung cancer cell line A549 and in animals in vivo. The synergy may be achieved by growth inhibition and apoptosis in-duction.     

Experimental Study on the Inhibitory Effects of Verapamil on the Proliferation of Meningiomas Cells

In order to investigate the effects of verapamil on the proliferation of meningiomas cells in vitro and in vivo, the cultured meningiomas cells were cultured with verapamil at different concen-trations for 24 h and the inhibitory effects of verapamil on cell proliferation were observed by MTT method. The meningiomas model was established by implanting the newly removed tumor fragments into the nude mice subcutaneously. The nude mice with tumors were divided into two groups: vera-pamil-treated group and control group. Tumor volumes were measured and after 12 weeks the tumors were taken out and examined histologically. The expression of proliferating cell nuclear antigen (PCNA) in the tumors was detected by using immunohistochemistry. It was found that verapamil could inhibit the growth of cultured meningiomas cells in a concentration-dependant manner. The in-hibitory effect could be observed in the concentration of 1 μmol/L verapamil and the most obvious effects appeared in the concentration of 100 μmol/L. Tumor volume in the verapamiltreated group was obviously smaller than that in the control group (211.40±5.50 vs 163.94±3.62, P<0.01) and the expression of PCNA was also lower (1.52±0.24 vs 2.86±0.53, P<0.05). Tumor inhibition rate was about 22.45%. It was suggested that verapamil could inhibit the proliferation and growth of men-ingiomas cells in vitro and in vivo.     

The anti-proliferative effect of inhibitor of telomerase on cultured retinal pigment epithelial cells

Proliferative vitreoretinopathy (PVR) has ahigh rate of inducing blind and isone of the commonreasons for rhegematogenous retinal detachmentsurgery falling.If PVR recurred after vitrectomy,the secondary operation will be more difficult,thecurative effect decreased,even induce blind finally.The pathologic process of PVR is:followingrhegematogenous retinal detachment,the blood- reti-nal barrier was break,glial cells,retinal pigment ep-ithelial(RPE) cells,fibroblastcells and macrophagesmove t…     

Expression of macrophage inflammatory protein 1α in the endothelial cells exposed to diamide

Summary In order to study whether the endothelial cells (ECs) with lipid peroxidation induced by diamide can express and secrete macrophage inflammatory protein 1α (MIP-1α), the expression of MIP-1α protein in the cells was detected by cell enzyme-linked immunosorbent assay (ELISA) and that of MIP-1α mRNA was determined by cell in situ hybridization and nuclease S1 protection assay after the ECs were exposed to different concentrations of diamide for 4 h. The chemotactic activity of MIP-1α was tested by micropore filter method using modified Boyden chambers. Cell ELISA showed that the expression of MIP-1α protein in endothelial cells exposed to 1 μmol/L, 5 μmol/L and 10 μmol/L diamide was 1.9-fold, 2.3-fold and 1.7-fold respectively as much as that in the control cells, which was statistically significant by analysis of variance. In situ hybridization revealed that the mRNA expression of ECs treated with 1 μmol/L, 5 μmol/L and 10 μmol/L diamide was 1.3-fold, 3.0-fold and 1.7-fold as much as that in the control group, which had statistical significance (F=188. 93,P<0.01). The mRNA expression in 5 μmol/L dimide treated ECs, measured by nuclease S1 protection assay, was 3.4-fold as much as that in the control group (t=8.70,P<0.05). Chemotactic response (99.50±4.31 μm) to the culture medium conditioned by 5 μmol/L diamide treated ECs, which was stronger than that (66.47±3.25 μm) conditioned by the ECs (F=404.31,P<0.05), was significantly decreased (F=192.25,P<0.05) after adding MIP-1α antibody. It suggests that diamide, a lipid peroxidation inducer, could stimulate ECs to produce high level of MIP-1α, and might play an important role in atherogenesis by promoting the migration of peripheral blood monocytes into arterial intima. YANG Limin, female, born in 1973, M. D., Ph.D. This project was supported by a grant from National Natural Sciences Foundation of China (No. 39730220).     

The Effect of Connective Tissue Growth Factor on Human Renal Tubular Epithelial Cell Transdifferentiation

Summary To investigate the role of connective tissue growth factor (CTGF) in transdifferentiation of human renal tubular epithelial cell (HKC),in vitro cultured HKC cells were divided into 3 groups: negtive control, low dose CTGF-treated group (rh CTGF, 2.5 ng/ml) and high dose CTGF-treated (rhCTGF, 5. 0 ng/ml). Then the expression of α-smooth muscle actin (α-SMA) were assessed by indirect immuno-fluorescence, and the percentage of α-SMA positive cells were assessed by flow cytometry. RT-PCR were also performed to examine the mRNA level of α-SMA. Upon the stimulation of different concentrations of rhCTGF, the expression of α-SMA were markedly stronger than that in negative controls. The percentages of α-SMA positive cells were significantly higher in the stimulated groups than that of negative controls (38.9%, 65.5% vs 2.4%,P<0.01). α-SMA mRNA levels were also up-regulated by the stimulation of rhCTGF (P<0.01). These results suggest that CTGF can promote the transdifferentiation of human renal tubular epithelial cells towards myofibroblast (Myo-F). ZHANG Chun, male, born in 1977, M. D., Ph. D. This work was supported by a grant from the Science & Technology Foundation of Hubei Province (No. 2003AA301C14).     

Elevated homocysteine and C-reactive protein levels independently predict worsening prognosis after stroke in Chinese patients

Increased plasma total homocysteine (tHcy) and high sensitivity C-reactive protein (hsCRP) levels are independent risk factors for cardiovascular disease.However, the predictive value of tHcy in combination with hsCRP in patients with stroke is not known.To determine the relationship between tHcy and hsCRP, we enrolled 291 patients with first-onset stroke (196 ischemic and 95 hemorrhagic).Plasma tHcy and hsCRP levels were measured and subsequent vascular events and deaths were determined over a 5-year period.Using the arbitrary cutoff for tHcy (<18 μmol/L and ≥18 μmol/L) and hsCRP (<1 mg/L, 1-3 mg/L and >3 mg/L), the patients were divided into 6 groups.Survival analysis showed that the probability of death or new vascular events during a 5-year follow-up increased according to tHcy and hsCRP levels (P<0.01).The relative risk (RR) of death or new vascular events was 4.67 (95% CI, 1.96 to 11.14, P=0.001) in patients with high tHcy (≥18 μmol/L) and hsCRP (>3 mg/L) compared with those with low tHcy (<18 μmol/L) and hsCRP (<1 mg/L).The increased tHcy level (≥18 μmol/L) combined with increased hsCRP level (>3 mg/L) was still significantly associated with the risk of death or new vascular events (RR, 4.10, 95% CI, 1.61 to 10.45, P=0.003) even when adjusted for other risk factors at inclusion.The combination of increased tHcy and hsCRP levels had a stronger predictive value than increased hsCRP alone or increased tHcy level alone.Further studies are required to evaluate the potential decrease in risks associated with lowering both Hcy and hsCRP levels in patients that present with both increased tHcy and hsCRP.     

Different Effects of Capsaicin on IA and IK in Pain-conduct Neurons of Rats

Capsaicin,themajoringredientinchilipep persandresponsibleforitspungenttaste,isaspe cificactivatorofnociceptoronpain conductneu rons[1].Nowcapsaicinanditsanaloguehavebeenusedinclinicasanewanalgesic[1,2].Themechanismofcapsaicinonpain conductneuronshasn'tbeenunderstoodclearlynow.Theearlierworkofourlaboratorydiscoveredthatcap saicincouldsignificantlyinhibittheactionpoten tials(APs)andthevoltage gatedsodiumchannels(VGSCs)inpain conductneuronsatlowconcen tration(1μmol/L)[3].Thepurposeofthisstudy…     

Experimental and clinical studies on inhibitory effect of Ganoderma lucidum on platelet aggregation

Summary In this study we observed the inhibitory effect of Chinese herbal medicine Ganoderma lucidum (GL) on platelet aggregation in 15 healthy volunteers and 33 patients with atherosclerotic diseases. The results showed that the first and the second phase of aggregation of platelets of the healthy volunteers were obviously inhibited (P<0.0l) when watery soluble extract of GL of different concentrations was added to the platelets in vitro, i. e., the reaction speed of platelet aggregation was slowed down. The inhibitory effect was related to dosage. Platelet aggregation induced by ADP in final concentration of 2 μmol/L and 3 μmol/L was obviously inhibited, after the patients had taken GL 1 g 3 times a day for 2 weeks, the maximum platelet aggregation inhibition rates were then 31.49 % (P<0.0l) and 17.7 % (P<0.0l) respectively. Length and weights (wet and dry) of the extracorporeal thrombi were reduced from 30.05±4.38 mm, 103.9±9.33mg and 44.89±4.79 mg to 20.4±2.33 mm (P<0.05), 85.27±8.77 mg (P<0.0l) and 35.1=±4.5 mg (P<0.0l) respectively after oral administration of GL. The results of our experiments suggested that the Chinese herbal medicine GL may be an effective inhibitory agent of platelet aggregation. However, its mechanism and active principles remain to be further investigated.