Patients' expectancy scale of acupuncture: Development and clinical performance test.

PURPOSE: This study aims to develop and validate a concise tool for evaluating acupuncture expectancy that is easy to understand and conforms to acupuncture characteristics. MATERIALS AND METHODS: A draft was created using the Delphi consensus method. Reliability, validity, discrimination, and feasibility tests were conducted at the item and scale levels. RESULTS: The scale themes were defined as disease-related, treatment-related, process-related, and outcome-related. After two rounds of Delphi surveys with good experts' reliability (authority coefficients of experts were 0.86 and 0.87 in the two rounds) and agreement (Kendall's concordance coefficient of the participants were 0.33 and 0.15 in the two rounds, P < 0.05), 11 items (the mean score for item importance, full mark ratios, and coefficient of variation of items were ≥3.5, ≥25%, and ≤0.30, respectively) were included in the draft. A total of 145 individuals were recruited to test the draft. Reliability was assessed by Cronbach's α coefficient (0.90), split-half reliability coefficient (0.89), and test-retest reliability (Pearson's coefficient = 0.74, P < 0.05). Content validity was assessed by the content validity index (Item-CVI ≥ 0.78 and Scale-CVI/Ave = 0.92), and a confirmatory factor analysis was performed to assess the construct validity. The discrimination of scale items was evaluated by the critical ratio (CR > 3.00) and the homogeneity test (item-total correlations >0.40). Feasibility was assessed through the acceptance rate (recovery rate = 98.60%, response rate = 100%), completion rate (100%), and completion time (4.99 ± 6.80 min). CONCLUSION: The patients' expectancy scale of acupuncture (PESA) consists of 11 items with four themes, disease-related, treatment-related, process-related, and outcome-related. It has great reliability, validity, discrimination, and feasibility and has the potential to evaluate acupuncture expectancy in clinical trials.

Impact of Azithromycin on Forsythiaside Pharmacokinetics in Rats: A Population Modeling Method.

OBJECTIVE: Lianhuaqingwen and Shuanghuanglian are drug treatment options for Corona Virus Disease 2019 (COVID-19). In China, use of traditional Chinese medicine with Shuanghuanglian or Lianhuaqingwen (for them, forsythiaside is the active antiviral and antibacterial component) in combination with azithromycin is common for the treatment of pediatric pneumonia. It is important to understand the reason why the combination of these compounds is better than a single drug treatment. This study aimed to explore the pharmacokinetic interaction between forsythiaside and azithromycin. METHODS: Twelve male Sprague-Dawley rats were randomly divided into an experimental group (Forsythia suspensa extract and azithromycin) and a control group (a single dose of Forsythia suspensa extract in 5% glucose solution). Plasma samples were collected at scheduled time points, and the high-performance liquid chromatography combined with ultraviolet method was used to determine the plasma forsythiaside concentration. Non-compartmental analysis and population pharmacokinetic methods were used to investigate the forsythiaside pharmacokinetic difference between the experimental and control group. RESULTS: Compared with a single administration, the area under the curve and half-life of forsythiaside increased, and forsythiaside clearance decreased significantly after co-administration with azithromycin. The in vivo behavior of forsythiaside could be described by the one compartment model. The forsythiaside clearance decreased when combined with azithromycin. Visual evaluation and bootstrap results suggested that the final model was precise and stable. CONCLUSION: Co-administration of azithromycin can significantly decrease the forsythiaside clearance and increase drug exposure. A lower dose of azithromycin can obtain sufficient forsythiaside concentration to provide antiviral and antibacterial activity.

Bear bile powder attenuates senecionine-induced hepatic sinusoidal obstruction syndrome in mice.

Hepatic sinusoidal obstruction syndrome (HSOS) via exposure to pyrrolizidine alkaloids (PAs) is with high mortality and there is no effective treatment in clinics. Bear bile powder (BBP) is a famous traditional animal drug for curing a variety of hepatobiliary diseases such as cholestasis, inflammation, and fibrosis. Here, we aim to evaluate the protective effect of BBP against HSOS induced by senecionine, a highly hepatotoxic PA compound. Our results showed that BBP treatment protected mice from senecionine-induced HSOS dose-dependently, which was evident by improved liver histology including reduced infiltration of inflammatory cells and collagen positive cells, alleviated intrahepatic hemorrhage and hepatic sinusoidal endothelial cells, as well as decreased conventional serum liver function indicators. In addition, BBP treatment lowered matrix metalloproteinase 9 and pyrrole-protein adducts, two well-known markers positively associated with the severity of PA-induced HSOS. Further investigation showed that BBP treatment prevents the development of liver fibrosis by decreasing transforming growth factor beta and downstream fibrotic molecules. BBP treatment also alleviated senecionine-induced liver inflammation and lowered the pro-inflammatory cytokines, in which tauroursodeoxycholic acid played an important role. What's more, BBP treatment also decreased the accumulation of hydrophobic bile acids, such as cholic acid, taurocholic acid, glycocholic acid, as well. We concluded that BBP attenuates senecionine-induced HSOS in mice by repairing the bile acids homeostasis, preventing liver fibrosis, and alleviating liver inflammation. Our present study helps to pave the way to therapeutic approaches of the treatment of PA-induced liver injury in clinics.

The protective effect of ritonavir against Gynura japonica-induced liver injury in rats / 药学学报

Numerous in vitro studies have shown that most pyrrolizidine alkaloids (PAs) are hepatotoxic after being metabolically activated by cytochrome P450 (CYP) 3A4. However, the key role of CYP3A4 has not been confirmed in vivo. Therefore, the CYP3A4 chemical inhibitor ritonavir was employed in this work and the effect of ritonavir on Gynura japonica-induced liver injury in rats was investigated. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine. Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. Acute liver injury was induced by a single gavage of Gynura japonica extracts (GJE, 8 g·kg-1); rats in the protection group were gavaged with ritonavir (RIT, 30 mg·kg-1) 1 h before GJE treatment. The results show that RIT could significantly attenuate GJE-induced liver injury in rats. Rats in the protection group showed decreased serum activities for alanine aminotransferase and aspartate aminotransferase, as well as lower total bile acids. In addition, the infiltration of inflammatory cells, sinusoidal hemorrhage, and hepatic necrosis in GJE-treated rats were markedly attenuated in the protection group. The content of pyrrole-protein adducts (PPAs), a recommended biomarker for PA-induced hepatotoxicity in clinics, was determined at 10 min to 24 h after GJE treatment. The content of 13 bile acids was also quantified. RIT treatment reduced the content of PPAs in serum dramatically and restored the impaired bile acid homeostasis caused by GJE. These studies indicate that RIT attenuated Gynura japonica-induced liver injury in rats, which was closely related to the inhibition of the metabolic activation of PAs and the regulation of bile acid metabolism. These results provide a better understanding of the relationship between CYP3A4 and PA-induced toxicity. This work will also be helpful in developing effective treatments for PA-induced liver injury and making a reasonable evaluation of the safety of drugs containing PAs in clinic.

The protective effect of salvianolic acid B against senecionine-induced hepatotoxicity in mice / 药学学报

In recent years, there has been an increase in the incidence of herbal-induced liver injury due to the accidental ingestion of herbal medicines containing pyrrolizidine alkaloids (PAs) in domestic. Salvianolic acid B (Sal B), a hydrophilic component in Salvia miltiorrhiza Bge., shows activities of anticoagulation, antioxidation, and other pharmacological activities. This research aims to investigate the protective effect of Sal B on hepatotoxicity induced by senecionine (SEN) and its potential mechanism. The animal experiment was approved by the Experimental Animal Ethical Committee of Shanghai University of Traditional Chinese Medicine, and all mice have received humane care in compliance with the institutional animal care guidelines. Mice were treated with Sal B (10 mg·kg-1) 3 days before and 1 day after SEN (50 mg·kg-1) treatment. The animals were sacrificed 48 h after SEN administration. As a result, Sal B effectively ameliorated SEN-induced liver injury. The mice in the group treated with Sal B showed lower serum activities of alanine aminotransferase and aspartate aminotransferase, less hepatic sinusoidal hemorrhage, and reduced hepatocyte necrosis. Besides, contents of pyrrole-protein adducts, the marker for PA-induced toxicity, were also decreased in serum. The key factors related to coagulation, oxidative stress, and liver fibrosis were further analyzed. It was found that Sal B inhibited the coagulant system by reducing the expression of plasminogen activator inhibitor-1. Sal B also modulated glutathione and superoxide dismutase levels and improved the anti-oxidative defense system. In addition, Sal B decreased the excessive deposition of extracellular matrix and inhibited the progression of liver fibrosis via down-regulating several key factors related to liver fibrosis, including matrix metalloproteinase 9, transforming growth factor-β1, signal transducer and activator of transcription 3, and chemokine 1. In conclusion, Sal B ameliorated SEN-induced liver injury in mice by regulating the blood coagulation system, improving oxidative stress, and modulating liver fibrosis-related factors. Our present study pointed to the possibility of utilizing salvianolic acid B for protection against PA-induced liver injury clinically.

The protective effects and mechanism of Alismatis Rhizoma extracts against senecionine-induced acute liver injury in mice / 药学学报

Drug-induced liver injury and herbal preparations containing pyrrolizidine alkaloid (PA) have gained global attention. The purpose of this research was to investigate the effects and mechanisms of Alismatis Rhizoma, a traditional Chinese medicine, to protect against acute liver injury in mice induced by senecionine (SEN), a representative toxic PA compound. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine. Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. Acute liver injury was induced by a single intragastric administration of SEN (50 mg·kg-1). Mice in the protection groups received intragastric administration of Alismatis Rhizoma water extract (WE, 18 g·kg-1 per day) or ethanol extract (EE, 18 g·kg-1 per day) 5 days before SEN treatment. The results show that Alismatis Rhizoma extracts can significantly attenuate acute liver injury in mice. Mice in the protection groups showed decreased serum activities of alanine aminotransferase and aspartate aminotransferase, as well as decreased total bile acids. In addition, the infiltration of inflammatory cells, sinusoidal hemorrhage, and hepatic necrosis in SEN-treatment mice was clearly attenuated in the protection groups. Interestingly, EE showed a better effect than WE. The content of principal bile acids in serum and the mRNA and protein expression of key factors related to bile acid metabolism were also measured. Alismatis Rhizoma up-regulated the bile acid transporters and drug metabolism enzymes, consistent with the observed bile acid homeostasis and alleviation of SEN-induced injury to hepatocytes. The present study points to the possibility of utilizing Alismatis Rhizoma for protection against liver injury caused by drugs and preparations containing PA.

Curcumin inhibits the formation of atherosclerosis in ApoE-/- mice by suppressing cytomegalovirus activity in endothelial cells.

BACKGROUND: Curcumin (Cur) is a hydrophobic polyphenol compound derived from the rhizome of the herb Curcuma longa. Cur has a wide spectrum of biological and pharmacological activities. It has been shown that human cytomegalovirus (HCMV) infection was an important risk factor for atherosclerosis (AS) and Cur exhibited an outstanding anti-HCMV effect. However, anti-AS effects of Cur remain unclear when HCMV infected endothelial cells. AIMS: This study will investigate the anti-AS activities and mechanism of Cur,when HCMV infected in vivo and in vitro. MATERIALS AND METHODS: Cur (0.5, 1, and 2 µM) was used to explore the anti-AS activities and mechanism after HCMV infected endothelial cells in vitro. ApoE-/- mice were fed a high fat and cholesterol diet (HD) and given 4000,000 copies/mouse MCMV infection by intraperitoneal and treated with ganciclovir (5 mg/kg/d), Cur (25, 15 mg/kg/d) for 10 weeks in vivo. KEY FINDINGS: As our results showed that Cur inhibited CMV replication and proliferation, reduced the intracellular ROS overproduction, decreased the release of inflammatory cytokines, down-regulated the level of HMGB1-TLRS-NF-κB signaling pathway-related proteins in vitro experiments. Cur reduced the serum levels of LDL-C, TC and TG, significantly decreased the formation of atherosclerotic plaque in the aorta, reduced the lipid deposition in liver and inflammatory damage in heart, lung and kidney in vivo experiments. SIGNIFICANCE: This study showed that Cur prevent AS progression by inhibiting CMV activity and CMV-induced HMGB1-TLRS-NF-κB signaling pathway.

Coix seed oil prolongs lifespan and enhances stress resistance in Caenorhabditis elegans.

Coix seed oil (CSO) has many beneficial effects, but there is limited research on its influence on the processes and mechanisms related to senescence. Here, we used Caenorhabditis elegans as an in vivo model to investigate CSO's bioeffects on longevity. CSO (1 mg/mL) significantly extended the mean lifespan of C. elegans by over 22.79% and markedly improved stress resistance. Gene-specific mutant studies showed that the CSO-mediated increase in life expectancy was dependent on mev-1, hsf-1 and daf-16, but not daf-2. Furthermore, CSO significantly upregulated stress-inducible genes, including daf-16 and its downstream genes (sod-3, hsp-16.2 and gst-4). In addition, four major fatty acids, linoleic, oleic, palmitic and stearic, played leading roles in C. elegans' extended lifespan. Thus, CSO increased the life expectancy of, and enhanced the stress resistance in, C. elegans mainly through daf-16 and its downstream genes, but not through the insulin/insulin-like growth factor 1 signaling pathway.

Akebia saponin D alleviates hepatic steatosis through BNip3 induced mitophagy.

Akebia Saponin D (ASD) is the most abundant constituent of the rhizome of Dipsacus asper Wall. The prior studies have shown that ASD alleviates hepatic steatosis targeted at the modulation of autophagy and exerts hepatoprotective effects through mitochondria. However, it is still unclear which signal transduction pathway that ASD increase autophagy and protect the mitochondria. The purpose of this paper was to explore the mechanisms through which ASD alleviates hepatic steatosis. ASD significantly reduced lipid accumulation in BRL cells. Furthermore, ASD significantly increased the mitophagy acting as increase the colocalization between mitochondria and punctate EGFP-LC3. ASD treatment increased the expression of BNip3, phospho-AMPK, prevented oleic acid (OA) induced LC3-II and phospho-mTOR expression. These effects were similar to the effects cotreatment with rapamycin. ASD treatment could not attenuate the expression of BNip3 blocked by chloroquine (CQ) or siRNA-mediated knockdown of BNip3. These results suggest that Akebia saponin D alleviates hepatic steatosis targeted at BNip3 mediated mitophagy. Activation of BNip3 via ASD may offer a new strategy for treating NAFLD.

[Effect of Zhenwu Tang on regulating of "AVP-V2R-AQP2" pathway in NRK-52E cells].

This study was aimed to investigate the effect and mechanism of Zhenwu Tang on AVP-V2R-AQP2 pathway in NRK-52E cells in vitro. Forty eight male SD rats were randomly divided into eight groups with 6 animals in each group. Distilled water or 22.68 g·kg⁻¹·d⁻¹ Zhenwu Tang(calculated by raw drug dosage meter) was given by gavage. Blood samples were collected by cardiac puncture， and the medicated serum was centrifuged from the blood by 3 000 r·min⁻¹. NRK-52E cells were treated with different medicated serum or dDAVP. The condition of cell proliferation was detected by RTCA. The distribution of V2R and AQP2 in cells were detected by immunofluorescence. The expression of V2R， PKA and AQP2 were detected by Western blot and AQP2 mRNA level was detected by real-time PCR. Results showed that the level of AQP2 mRNA(P<0.01) and protein expression of V2R， PKA and AQP2(P<0.05， P<0.01， P<0.05) of Z7d group which was treated with Zhenwu Tang medicated serum for 24 h were significantly higher than that of normal rat serum group. And the expression level of V2R， p-AQP2 and AQP2(P<0.01， P<0.05， P<0.01) of Z7d+dDAVP group were significantly increased comparing to normal rat serum group. The results indicate that the applying of Zhenwu Tang medicated serum could increase the expression level of V2R， PKA and AQP2 which exist in AVP-V2R-AQP2 pathway in NRK-52E， and there is synergistic effect between Zhenwu Tang medicated serum and dDAVP. So the pathway of AVP-V2R-AQP2 may be one of the mechanism for which Zhenwu Tang regulate balance of water transportation.

[Protective effect of ß-asarone on AD rat model induced by intracerebroventricular injection of Aß1₋42 combined 2-VO and its mechanism].

This study was aimed to investigate the protective effect and mechanism of ß-asarone on the animal model of Alzheimer's disease(AD) which was induced by intracerebroventricular injection of Aß1₋42 combined cerebral ischemia. One hundred and five rats were randomly divided into seven groups including sham-operated group, AD model group, ß-asarone 10 mg•kg⁻¹ group, ß-asarone 20 mg•kg⁻¹ group, ß-asarone 30 mg•kg⁻¹ group, donepezil group(0.75 mg•kg⁻¹) and Ginkgo biloba extract group(24 mg•kg⁻¹). Rats' learning and memory abilities, cerebric regional blood flow, pathological changes in hippocampal CA1 region, the expression level of HIF-1α and serum CAT, SOD and MDA level were detected 4 weeks later. The results showed that the application of intracerebroventricular injection of Aß1₋42 joint 2-VO could lead to rats' dysfunction of learning and memory, decrease in regional cerebral blood flow. Neurons in CA1 region were arranged in disorder, and amyloid deposition was increased. The number of cerebral cortical cells expressing HIF-1α was increased as well. The level of serum CAT and SOD decreased, while level of serum MDA increased. However these symptoms were improved by 20 mg•kg⁻¹ and 30 mg•kg⁻¹ ß-asarone. The results indicated that ß-asarone could effectively relieve the symptoms of the AD model induced by intracerebroventricular injection of Aß1₋42 combined cerebral ischemia, and the potential mechanism might be that it could attenuate damage of MDA to the body by improving the level of CAT and SOD, meanwhile the level of HIF-1α decreased as the decline of hyperoxide which might attenuate its damage to neuron, so it finally achieved alleviating Alzheimer's disease.

Neuroprotective Effects and Mechanism of ß-Asarone against Aß1-42-Induced Injury in Astrocytes.

Emerging evidence suggests that activated astrocytes play important roles in AD, and ß-asarone, a major component of Acorus tatarinowii Schott, was shown to be a potential therapeutic candidate for AD. While our previous study found that ß-asarone could improve the cognitive function of rats hippocampally injected with Aß, the effects of ß-asarone on astrocytes remain unclear, and this study aimed to investigate these effects. A rat model of Aß1-42 (10 µg) was established, and the rats were intragastrically treated with ß-asarone at doses of 10, 20, and 30 mg/kg or donepezil at a dose of 0.75 mg/kg. The sham and model groups were intragastrically injected with an equal volume of saline. Animals were sacrificed on the 28th day after administration of the drugs. In addition, a cellular model of Aß1-42 (1.1 µM, 6 h) was established, and cells were treated with ß-asarone at doses of 0, 2.06, 6.17, 18.5, 55.6, and 166.7 µg/mL. ß-Asarone improved cognitive impairment, alleviated Aß deposition and hippocampal damage, and inhibited GFAP, AQP4, IL-1ß, and TNF-α expression. These results suggested that ß-asarone could alleviate the symptoms of AD by protecting astrocytes, possibly by inhibiting TNF-α and IL-1ß secretion and then downregulating AQP4 expression.

Effect of apoptosis on gastric adenocarcinoma cell line SGC-7901 induced by cis-9, trans-11-conjugated linoleic acid.

AIM: To determine the effect of apoptosis on gastric cancer cells (SGC-7901) induced by cis-9, trans-11-conjugated linoleic acid (c9, t11-CLA) and its possible mechanism in the inhibition of cancer cells growth. METHODS: Using cell culture, flow cytometery and immunocytochemical techniques, we examined the cell growth, frequency of apoptosis and distribution of cell cycle, expression of ki67, bcl-2, Fas, and c-myc of SGC-7901 cells which were treated with various c9, t11-CLA concentrations (25,50,100 and 200 micromol x L(-1)) of c9, t11-CLA for 24 h and 48 h, with a negative control (0.1 % ethanol). RESULTS: The growth of SGC-7901 cells was inhibited by c9,t11-CLA. Eight days after treatment with various concentrations of c9,t11-CLA, as mentioned above, the inhibition rates were 5.9 %, 20.2 %,75.6 % and 82.4 %, respectively. The frequency of apoptosis on SGC-7901 cells induced by different concentrations of c9, t11-CLA (except for 25 micromol.L(-1), 24 h) was significantly greater than that in the negative control (P<0.01). To further investigate the influence of the cell cycle progression, we found that apoptosis induced by c9, t11-CLA may be involved in blocking the cell cycle of SGC-7901 cells. Immunocytochemical staining demonstrated that SGC-7901 cells preincubated in media supplemented with different c9, t11-CLA concentrations for various time periods significantly decreased the expressions of ki67 (the expression rates were 18.70-3.20 %, at 24 h and 8.10-0.20 % at 48 h, respectively), bcl-2 (4.30-0.15 % at 24 h and 8.05 %-0 at 48 h), and c-myc (4.85-2.20 % at 24 h and 4.75-0.30 % at 48 h) as compared with those in the controls (the expressions of ki67, bcl-2, and c-myc were 15.1 % at 24 h and 13.5 % at 48 h, 6.80 % at 24 h and 8.00 % at 48 h, 5.50 % at 24 h and 5.30 % at 48 h, respectively) (P<0.01), whereas the expressions of Fas were increased (0.60-2.75 %, 24 h and 0.45-5.95 %, 48 h). CONCLUSION: The growth and proliferation of SGC-7901 cells are inhibited by c9, t11-CLA via blocking the cell cycle, pathways of bcl-2-associated mitochondria with reduced expression of bcl-2 and Fas-associated death domain protein (FADD) with enhanced expression of Fas. But expression of c-myc on SGC-7901 cells is lower than that in negative control, which needs to be studied further.

Effects ofcis-9,trans-11-conjugated linoleic acid on cancer cell cycle.

OBJECTIVES: To determine the effect of cis-9, trans-11-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and its possible mechanism of inhibition cancer growth. METHODS: Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/wafl) of MCF-7 cells which were treated with various c9, t11-CLA concentrations (25 mM, 50 mM, 100 mM and 200 mM) of c9, t11-CLA for 24 and 48 h, with negative controls (0.1% ethanol). RESULTS: The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9, t11-CLA. MCF-7 cells, after treatment with various c9, t11-CLA doses mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively and the inhibitory effect of c9, t11-CLA on DNA synthesis (except for 25 mM, 24 h) incorporated significantly less(3)H-TdR than did the negative control (P<0.05 andP<0.01). To further investigate the influence on the cell cycle progression, we found that c9, t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that MCF-7 cells preincubated in media supplemented with different c9, t11-CLA concentrations at various times significantly decreased the expressions of PCNA, and Cyclin, A, B(1), D(1) compared with the negative controls (P<0.01), whereas the expressions of p16(ink4a) and p21(cip/wafl), cyclin-dependent kinases inhibitors (CDKI), were increased. CONCLUSIONS: The cell growth and proliferation of MCF-7 cells is inhibited by c9, t11-CLA by blocking the cell cycle, which reduces expressions of cyclin A, B(1), D(1) and enhances expressions of CDKI (p16(ink4a) and p21(cip/wafl)).

Effects ofcis-9,trans-11-conjugated linoleic acid on cancer cell cycle

<p><b>OBJECTIVES</b>To determine the effect of cis-9, trans-11-conjugated linoleic acid on the cell cycle of mammary cancer cells (MCF-7) and its possible mechanism of inhibition cancer growth.</p><p><b>METHODS</b>Using cell culture and immunocytochemical techniques, we examined the cell growth, DNA synthesis, expression of PCNA, cyclin A, B(1), D(1), p16(ink4a) and p21(cip/wafl) of MCF-7 cells which were treated with various c9, t11-CLA concentrations (25 mM, 50 mM, 100 mM and 200 mM) of c9, t11-CLA for 24 and 48 h, with negative controls (0.1% ethanol).</p><p><b>RESULTS</b>The cell growth and DNA synthesis of MCF-7 cells were inhibited by c9, t11-CLA. MCF-7 cells, after treatment with various c9, t11-CLA doses mentioned above for 8 days, the inhibition frequency was 27.18%, 35.43%, 91.05%, and 92.86%, respectively and the inhibitory effect of c9, t11-CLA on DNA synthesis (except for 25 mM, 24 h) incorporated significantly less(3)H-TdR than did the negative control (P<0.05 andP<0.01). To further investigate the influence on the cell cycle progression, we found that c9, t11-CLA may arrest the cell cycle of MCF-7 cells. Immunocytochemical staining demonstrated that MCF-7 cells preincubated in media supplemented with different c9, t11-CLA concentrations at various times significantly decreased the expressions of PCNA, and Cyclin, A, B(1), D(1) compared with the negative controls (P<0.01), whereas the expressions of p16(ink4a) and p21(cip/wafl), cyclin-dependent kinases inhibitors (CDKI), were increased.</p><p><b>CONCLUSIONS</b>The cell growth and proliferation of MCF-7 cells is inhibited by c9, t11-CLA by blocking the cell cycle, which reduces expressions of cyclin A, B(1), D(1) and enhances expressions of CDKI (p16(ink4a) and p21(cip/wafl)).</p>