Gossypol acetic acid regulates leukemia stem cells by degrading LRPPRC via inhibiting IL-6/JAK1/STAT3 signaling or resulting mitochondrial dysfunction

BACKGROUND Leukemia stem cells(LSCs)are found to be one of the main factors contributing to poor therapeutic effects in acute myeloid leukemia(AML),as they are protected by the bone marrow microenvironment(BMM)against conventional therapies.Gossypol acetic acid(GAA),which is extracted from the seeds of cotton plants,exerts anti-tumor roles in several types of cancer and has been reported to induce apoptosis of LSCs by inhibiting Bcl2.AIM To investigate the exact roles of GAA in regulating LSCs under different microenvironments and the exact mechanism.METHODS In this study,LSCs were magnetically sorted from AML cell lines and the CD34+CD38-population was obtained.The expression of leucine-rich pentatricopeptide repeat-containing protein(LRPPRC)and forkhead box M1(FOXM1)was evaluated in LSCs,and the effects of GAA on malignancies and mitochondrial RESULTS LRPPRC was found to be upregulated,and GAA inhibited cell proliferation by degrading LRPPRC.GAA induced LRPPRC degradation and inhibited the activation of interleukin 6(IL-6)/janus kinase(JAK)1/signal transducer and activator of transcription(STAT)3 signaling,enhancing chemosensitivity in LSCs against conventional chemotherapies,including L-Asparaginase,Dexamethasone,and cytarabine.GAA was also found to downregulate FOXM1 indirectly by regulating LRPPRC.Furthermore,GAA induced reactive oxygen species accumulation,disturbed mitochondrial homeostasis,and caused mitochondrial dysfunction.By inhibiting IL-6/JAK1/STAT3 signaling via degrading LRPPRC,GAA resulted in the elimination of LSCs.Meanwhile,GAA induced oxidative stress and subsequent cell damage by causing mitochondrial damage.CONCLUSION Taken together,the results indicate that GAA might overcome the BMM protective effect and be considered as a novel and effective combination therapy for AML.

Ponatinib and gossypol act in synergy to suppress colorectal cancer cells by modulating apoptosis/autophagy crosstalk and inhibiting the FGF19/FGFR4 axis

Objective:To evaluate the efficacy of ponatinib plus gossypol against colorectal cancer HCT-116 and Caco-2 cells.Methods:Cells were treated with ponatinib and/or gossypol at increasing concentrations to evaluate synergistic drug interactions by combination index.Cell viability,FGF19/FGFR4,and apoptotic and autophagic cell death were studied.Results:Ponatinib(1.25-40μM)and gossypol(2.5-80μM)monotherapy inhibited HCT-116 and Caco-2 cell viability in a doseand time-dependent manner.The combination of ponatinib and gossypol at a ratio of 1 to 2 significantly decreased cell viability(P<0.05),with a>2-and>4-fold reduction in IC50,respectively,after 24 h and 48 h,as compared to the IC50 of ponatinib.Lower combined concentrations showed greater synergism(combination index<1)with a higher ponatinib dose reduction index.Moreover,ponatinib plus gossypol induced morphological changes in HCT-116and Caco-2 cells,increased beclin-1 and caspase-3,and decreased FGF19,FGFR4,Bcl-2 and p-Akt as compared to treatment with drugs alone.Conclusions:Gossypol enhances ponatinib's anticancer effects against colorectal cancer cells through antiproliferative,apoptotic,and autophagic mechanisms.This may open the way for the future use of ponatinib at lower doses with gossypol as a potentially safer targeted strategy for colorectal cancer treatment.

Apogossypolone诱导骨髓瘤细胞凋亡及其机制研究

本研究探讨棉酚衍生物apogossypolone(ApoG2)对多发性骨髓瘤细胞系的抑制增殖、诱导凋亡的作用及其作用机制。应用台盼蓝染色、Hoechst 33258染色、透射电子显微镜检、DNA凝胶电泳法、流式细胞仪分析细胞DNA含量等来判断ApoG2对多发性骨髓瘤细胞的抑制增殖和诱导凋亡作用。以caspase-3、caspase-9以及BCL-2、BCL-XL分析ApoG2诱导骨髓瘤细胞凋亡的可能机制。结果表明:ApoG2对多发性骨髓瘤细胞增殖具有明显的抑制作用,IC50值在U266细胞和Wusl细胞(48小时)分别为0.1、0.2μmol/L。ApoG2可以诱导骨髓瘤细胞凋亡且呈时间和剂量依赖性。ApoG2可以使骨髓瘤细胞周期停止在G2期,U266细胞G2期比例从9.7%增至19.6%,Wusl细胞从9.8%增至31.7%。ApoG2能导致U266、Wusl细胞caspase-9、caspase-3活性增高。U266细胞和Wusl细胞经ApoG2 25μmol/L作用24小时后,BCL-XL表达分别下降(7.3±1.4)%和(11.2±6.2)%,Wusl细胞BCL-2表达下降84.4±3.4%。结论:ApoG2对多发性骨髓瘤细胞具有抑制增殖和诱导凋亡作用,其作用机制可能和下调BCL-2/BCL-XL表达以及影响细胞周期有关。

游离棉酚代谢产物gossypolone的半合成法制备及质谱表征

以棉酚为原料,采用半合成方法,制备棉酚氧化产物gossypolone,采用ESI-QTOF/MS飞行时间质谱和LCMS/MS对产物的结构进行验证,用HPLC分析产物的纯度。结果显示,产物的分子量、分子式、结构式均与棉酚氧化产物gossypolone一致,可以推测产物为棉酚氧化产物gossypolone,纯度≥95%。

Effect of dietary cottonseed meal on growth performance, physiological response, and gossypol accumulation in preadult grass carp, Ctenopharyngodon idellus

Cottonseed meal(CM) was used at up to 36.95% content in the diet(replacing 60% of dietary fish meal protein) without any negative effects on growth performance of pre-adult grass carp(initial body weight,761 g) under outdoor conditions.A culture trial was conducted in net cages installed in a large concrete pond.Seven isonitrogenous and isoenergetic diets containing a gradient of CM concentrations(0,12.2%,24.4%,36.6%,48.8%,54.8%,and 61.0%) as replacement for dietary fish meal protein(0,20%,40%,60%,80%,90%,and 100%) were formulated.Dietary non-resistant starch(from maize) was inverse to dietary CM.Growth performance and feed utilization of fish fed the diets containing CM replacing 0-40% fishmeal protein were not affected after the 6-week feeding trial.Accumulation of hepatopancreatic total gossypol in the hepatopancreas was significantly correlated with free gossypol content in the diets(HTG=88.6+1.5×DFG,R^2=0.89,P<0.05).Intestinal a-amylase and γ-glutamyl transpeptidase activities rose along with increasing dietary CM level.The structure of the mid-intestinal tissues and the ultrastructure of the enterocyte microvilli were normal when dietary CM was <36.6%(60% protein replacement).Increasing dietary CM content increased serum alanine aminotransferase levels but decreased serum alkaline phosphatase,cholesterol,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,triglycerides,and albumin(P<0.05).

Characterizing some gossypol and gossypolone Schiff's bases by studying their fragmentation patterns with electrospray ionization tandem mass spectra

To investigate the structural form of gossypol and gossypolone Schiff＇s bases, seven relevant Schiff＇s bases were synthesized and the electrospray ionization-tandem mass spectrometry （ESI-MS/MS） with low-energy collision-induced dissociation was used to analyze their fragmentations. A common fragmentation pathway with the loss of RNH2 from those schiff＇s bases quasi-molecular ions was observed and proposed on the basis of their MS/MS spectra data. This common pathway indicated that those Schiff＇s bases existed mainly as the enamine form not the imine form previously showed in most reports.

亚硒酸钠联合gossypol促进结直肠癌SW480细胞凋亡

目的研究亚硒酸钠和BCL-2/BCL-xl抑制剂gossypol在诱导结直肠癌细胞凋亡中的协同作用。方法将SW480分为6μmol/L gossypol组,10μmol/L亚硒酸钠组,gossypol与亚硒酸钠联合组(6μmol/L gossypol+10μmol/L亚硒酸钠),用Western blot检测经亚硒酸钠诱导后,SW480细胞中BCL-2家族蛋白的变化;用DAPI染色法,荧光显微镜检测细胞凋亡。用不同浓度的gossypol与亚硒酸钠混合处理BAX/BAK缺乏的MEF细胞,用锥虫蓝染色检测死亡率。结果亚硒酸钠作用于细胞后,Bim和BAX蛋白水平升高,而Mcl-1和BCL-xl表达下降(P<0.05)。亚硒酸钠和gossypol联合作用后,细胞的核裂解率,死亡率均比单独作用组明显上升(P<0.05)。在BAX/BAK双缺失的细胞中,gossypol仍能发挥促凋亡的作用。结论亚硒酸钠通过Bim和BAX增加结直肠癌SW480细胞的凋亡敏感性,gossypol通过降低肿瘤细胞对细胞凋亡的抵抗性,两者产生协同作用促进结直肠癌SW480细胞凋亡。

Low dose gossypol for male contraception

Aim: To ascertain whether the side effects of gossypol, hypokalemia and irreversibility, could be avoided on dose re-duction. Methods: Seventy-seven male volunteers were divided into 3 groups: control (22 cases), 10 mg gossypol(29 cases) and 12.5 mg (26 cases). Serum levels of testosterone, FSH and LH were measured by RIA and potassiumby flame photometry. Spema counts and motility were examined before and regularly after treatment for the evaluationof contraceptive efficacy. Results: The average sperm density and motility started to decrease significantly by theend of month 2 of medication and gradually reached the infertility levels ( < 4 million /mL) in both treated groups. Af-ter that the 10 mg group was asked to take the same dose every other day for up to a total observation period of 16-18months for the maintenance of infertility. Subjects in the 12.5 mg group did not take gossypol any more so as to ob-serve the length of the loading dose required, but in a few, a maintenance dose of 12.5 mg every other day was insti-tuted for a few more months. In both treated groups, none of the spouses was pregnant during the maintenance dose pe-riod. Serum levels of potassium, FSH, LH and testosterone were not significantly changed and not a single volunteercomplained of myoasthenia. After cessation of drug administratioin, the semen data returned to pretreatment levels.Conclusion: A regimen with 10 or 12.5 mg of gossypol as the daily loading dose and 35 or 43.75 mg as the week-ly maintenance dose could induce infertility in male volunteers without developing hypokalemia or irreversibility.(Asian J Androl 2000 Dec; 2: 283-287)

Gossypol inhibits proliferation of endometrioma cells in culture

Aim： To evaluate the anti-proliferative activity and mitochondrial toxicity of gossypol in endometrioma cells maintained in short-term cultures. Methods： （A） Three endometrioma cell lines from patients were treated with 25 or 50 nmol/L gossypol for up to 12 days. The effect of gossypol on the cell growth was recorded. （B） A phosphorescence oxygen analyzer was used to determine the effects of gossypol on mitochondrial oxygen consumption of six endometrioma cell lines from patients. （C） Cellular gossypol accumulations in three endometrioma cell lines from patients were measured by high-pressure liquid chromatography. Results： Proliferation of the endometrioma cells was inhibited by 25 and 50 nmol/L gossypol. Respiration of the endometrioma cells was inhibited by 10 μmol/L gossypol. Cellular gossypol was detected in the endometrioma cell lines that were treated for 24 h with l0 and 0.3 μmol/L gossypol. Conclusion： Gossypol invokes a potent toxicity on cultured endometrioma cells.

Determination of Gossypol in Trace Level by Flow Injection Analysis with Chemiluminescence Detection

This work reports the single-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium sensitized by gossypol. Under the optimum conditions, the CL intensity is proportional to the concentration of gossypol over the range of 1.11×10^-17-2.78×10^-16 mol/L in acid solution and 8.00×10^-11-7.39×10^-8mol/L in neutral solution with correlation coefficients 0.9983 and 0.9905, respectively. The detection limits is 1.60×10^-18 mol/L （S/N=3）. The proposed method has been applied for the determination of the gossypol in cottonseeds and pharmaceutical formulations with satisfactory results.

Influence of Gossypol on Ultrastructure and mRNA Expression of Bax and Bcl-2 in Mice Testis

The objective was to evaluate the toxicity effect of gossypol on ultrastructure of mouse testis and the expression of Bax mRNA and Bcl-2 mRNA of sperm cells in mice. Forty-eight male mice were randomly divided into four groups： control group, L-group （30 mg-kgt. d）, M-group （60 mg·kg-1 ·d） and H-group （120 mg·kg-1· d） and were orally administrated with gossypol diluted by sodium carboxymethyl cellulose （SCC） or SCC （control group） for 20 days. On the 21st day, all the mice were killed and ultrastructure changes of testis were observed by TEM. mRNA expression of Bax and Bcl-2 in testis was measured by semiquantitative RT-PCR. The results showed that the testicular ultrastructure in three treated groups was gradually damaged, according to the dosage of gossypol and cellular structure disordered and organdie degenerated, manifesting vacuolation of mitochondria, expansion of endoplasmie reticulum, mRNA expression of Bcl-2 in testis significantly increased （p〈0.05） in L-group and then significantly decreased （p〈0.05, p〈0.01） in M-group and H-group compared with that in the control group; mRNA expression of Bcl-2 in M-group and H-group significantly decreased （p〈0.05, p〈0.01） than that in L-group and Bcl-2 mRNA expression in H-group showed a significant decrease （p〈0.05） compared with that in M-group. On the other hand, mRNA expression of Bax significant increased （p〈0.05,p〈0.01） in M-group and H-group than that in the control group. The ratio of Bcl-2/Bax significantly reduced 07〈0.05, p〈0.01） in the treated group than that in the control group and was found to be an obvious dose-dependent. It demonstrated that the gnssypol could induce the changes on ultrastructure of mice testis, down-regulate mRNA expression of Bcl-2 and up-regnlate mRNA expression of Bax, which indicated that sperm ceils were induced apoptosis.

Feasibility study on the use of near-infrared spectroscopy for rapid and nondestructive determination of gossypol content in intact cottonseeds

Background:Gossypol found in cottonseeds is toxic to human beings and monogastric animals and is a primary parameter for the integrated utilization of cottonseed products.It is usually determined by the techniques relied on complex pretreatment procedures and the samples after determination cannot be used in the breeding program,so it is of great importance to predict the gossypol content in cottonseeds rapidly and nondestructively to substitute the traditional analytical method.Results:Gossypol content in cottonseeds was investigated by near-infrared spectroscopy(NIRS)and high-performance liquid chromatography(HPLC).Partial least squares regression,combined with spectral pretreatment methods including Savitzky-Golay smoothing,standard normal variate,multiplicative scatter correction,and first derivate were tested for optimizing the calibration models.NIRS technique was efficient in predicting gossypol content in intact cottonseeds,as revealed by the root-mean-square error of cross-validation(RMSECV),root-mean-square error of prediction(RMSEP),coefficient for determination of prediction(R_(p)^(2)),and residual predictive deviation(RPD)values for all models,being 0.05∼0.07,0.04∼0.06,0.82∼0.92,and 2.3∼3.4,respectively.The optimized model pretreated by Savitzky-Golay smoothing+standard normal variate+first derivate resulted in a good determination of gossypol content in intact cottonseeds.Conclusions:Near-infrared spectroscopy coupled with different spectral pretreatments and partial least squares(PLS)regression has exhibited the feasibility in predicting gossypol content in intact cottonseeds,rapidly and non destructively.It could be used as an alternative method to substitute for traditional one to determi ne the gossypol content in intact cottonseeds.

Valproic Acid Enhances the Anti-tumor Effect of(-)-gossypol to Burkitt Lymphoma Namalwa Cells

Burkitt lymphoma is a highly aggressive B-cell neoplasm. New therapeutic methods are needed to overcome the adverse effect of intensive chemotherapy regimens. Valproic acid and （-）-gossypol are two kinds of chemical compounds used as new anti-tumor drugs in recent years.

Synthesis, Characterization and Application of ZS/HMS Catalyst in the Esterification of Gossypol

A solid acid catalyst of zirconium sulfate (ZS) on a pure hexagonal mesoporous silica (HMS) sieve was prepared and characterized by small angle X-ray diffraction, NH3-temperature programmed desorption, and thermogravimetric analysis. The obtained ZS/HMS catalyst displayed a typical mesoporous structure, ZS was well dispersed on the HMS support, and the acidity increased with the amount of ZS loading. Gossypol was extracted from cottonseed cake with acetone as solvent, and then the gossypol solution was esterified with ZS/HMS as catalyst to yield products of acetic acid gossypol. Under the optimal conditions, the conversion efficiency of gossypol was as high as 96.7%.

Optimization of Cottonseed Meal De-gossypol Process by Extrusion via Genetic Algorithm Based on Artificial Neural Network

[ Objective] The paper aimed to optimize cottonseed meal de-gossypol process by extrusion. [ Method ] The artificial neural network （ANN） was used to stimulate the degradation of free gossypol in cottonseed meal by extrusion process, and a three-layer back propagation neural network was established to predict the degradation of free gossypol. [ Result] The result of 10-fold cross validation showed that the ANN with the training function as traingdx at hidden layer with eight neurons gave the smallest mean square error （MSE）. ANN predicted results were very close to the experimental results with correlation coefficient （R2 ） of 0.994 1 and RMSE of 0.497 1. A genetic algorithm （GA） based on the established neural network model was also used for optimizing de-gossypol process. The re- sults of GA showed that the optimal conditions of de-gossypol were puffing temperature 131℃, water ratio 51% , rotational speed 158 r/rain, and feeding speed 136 kg/h, while under this condition the degradation rate of free gossypol was 90.50%, which was close to the predicted result of CA with the small average relative er- ror of 1.38%. [ Conclusion] These results suggested that the GA based on a neural network model might be an excellent tool for optimizing cottonseed meal de-gos- sypol process.

GOSSYPOL-INDUCED ALTERATIONS OF AMINOPHOSPHOLIPID COMPOSITION IN HUMAN SPERM

Gossypol-induced alterations of aminophospholipid composition in human sperm wereobserved and the effects of some factors on these alterations were investigated.The altera-tions of aminophospholipid composition of human sperm induced by gossypoI included aprogressive decrease in the levels of phosphatidylethanolamine（PE）and phosphatidylserine（PS）when gossypol concentrations ranged from 5-500μmol/L,and a progressive increase inthe level of（LPE）at lower gossypol concentrations（5-50μmol/L）.The conversion of PEinto lysophosphatidylethanolamine（LPE）was strongly enhanced by Ca2+and inhibitedby 0.5mmol/L EDTA,while PMSF,NEM,iodoacetamide and Zn2+had no effect.Thisconversion was weaker in sperm with stripped surface proteins than in normal sperm.In addition,three surface proteins（MW 80,60 and 40 kD）were fixed on the plasmamembrane by gossypol treatment.The significance of gossypol action and the possibilitythat sperm PLA2, PE and.some surface proteins might play an important role in the physio-logical acrosome reaetion of human sperm,as well as in oocyte penetration,are discussed.

Omethoate-Induced Changes of (+)-δ-Cadinene Synthase Activity and Gossypol Content in Cotton Seedlings

The gene expression and activity of （＋）-δ-cadinene synthase during cotton development and in response to stress, as well as the spatial and temporal pattern of sesquiterpene biosynthesis, constitute one of chemical defense mechanisms in cotton plants. In order to explore the effects of omethoate on the cotton defense in relation to （＋）-δ-cadinene synthase and gossypol, effects of omethoate treatments on activity of （＋）-δ-cadinene synthase and gossypol content in cotton seedlings were investigated. Cotton seedlings treated with 400 mg L-1 omethoate exhibited a significant decrease in the specific activity of （＋）-δ-cadinene synthase from 12 to 120 h after treating when compared to the untreated control; significantly lower （＋）-δ-cadinene synthase activity was also observed in cotton seedlings treated with 200 mg L-1 omethoate from 72 to 120 h after treating; but for cotton seedlings treated with 100 mg L-1 omethoate, from 12 to 120 h after treating, no significant changes were observed for activity of （＋）-δ-cadinene synthase. The gossypol content in cotton seedlings treated with 100, 200 or 400 mg L-1 omethoate for different time periods showed no significant changes compared to that of the control. These results indicated that the activity of （＋）-δ-cadinene synthase in cotton seedlings in responses to exposure of omethoate at three concentrations for different time periods followed dose- and time-dependent responses to omethoate exposure. With omethoate as a chemical stress factor for cotton seedlings, the cotton defense in relation to the activity of （＋）-δ-cadinene synthase in cotton seedlings may be affected by omethoate application.

The Effect of Gossypol and Misoprostol on Luteal and Decidual Cells in Vitro

Gossypol and Misoprostol could directly damage the luteal and decidual cells cultured in vitro. The LD50 of gossypol alone to luteal and decidual cells were 1.27±0.09 μg/ml and 3.06±0.23 μg/ml, respectively; however when combined with misoprostol (to luteal cells 5μg/ml, or to decidual cells 10μg/ml), the LD50 of gossypol signifcantly decreased to 0.89±0.25 μg/ml and 1.88±0.26 μg/ml, respectively. The LD50 of misoprostol alone to luteal and decidual cells were 14.29±1.29μg/ml and 24.37±4.49 μg/ml, respectively; but it decreased to 8.79±2.18 μg/mland 17.29±1.56 μg/ml, respectively when combined with gossypol (to luteal cells 0.5 μg/ml, or to decidual cells 1.0 μg/ml), also showing statistical difference. The results suggested that the combination of gossypol with misoprostol had synergistic effect on the degeneration of luteal and decidual cells in vitro.

Effect of Extrusion Temperature on Free Gossypol and Nutritional Components of Cottonseed Meal

[ Objective] The paper aimed to study effects of extrusion temperature on free gossypol and nutritional components of cottonseed meal. [ Method ] Dif- ferent extrusion temperatures （90, 100, 110, 120 and 130℃ ） were designed, and contents of free gossypol and nutritional components in cottonseed meal were de- termined. [ Result] The optimal temperature for extrusion of cottonseed meal was 120℃, the degradation rate of free gossypol no longer increased with the increas- ing temperature when the temperature exceeded 120℃. The nitrogen solvable index （NSI） in cottonseed meal reduced quickly with the increase of extrusion temper- ature, and the contents of crude fiber, available lysine and total lysine in cottonseed meal decreased significantly, but the contents of total amino acids and essential amino acid reached maximums at the extrusion temperature of 120℃. The content of branched-chain amino acids also reached a maximum at 120℃. [ Conclusion] The extrusion temperature of 120℃ was preferred for lowering free gossypol significantly when maintaining higher nutritional value of cottonseed meal. The paper provided a certain technical basis for extrusion processing of cottonseed meal.