Impact of Luteinizing Hormone on IVF/ICSI Assisted Reproduction on the Initiation Day of Gonadotropin-releasing Hormone Antagonist Protocol.

OBJECTIVE: The aim of the study was to explore the optimal timing of gonadotropin initiation and the reasonable interval of luteinizing hormone (LH) levels in the gonadotropin-releasing hormone antagonist (GnRH-A) protocol. METHODS: A retrospective cohort study was conducted to analyze the data concerning the oocyte retrieval cycles from 1,361 cases with the GnRH-A protocol implemented. The ovarian responses (including AMH, AFC) in these patients were divided into the poor ovarian response group (an antral follicle count [AFC] ≤ 6, n = 394), the normal ovarian response group (an AFC > 6 and < 15, n = 570), and the high ovarian response group (an AFC ≥ 15, n = 397), according to the AFC. The patients were sub-grouped according to LH levels on the protocol initiation day, and the clinical outcomes (including dose of Gn initiation, Gn administration days, GnRH-ant administration days, P levels on the HCG day, E2 levels on the HCG day, LH levels on the HCG day, number of embryos transferred, total fertilization rate, embryo implantation rate(%), proportion of 2PN, proportion of good-quality embryos, endometrial thickness on the hCG injection day(mm), moderate to severe OHSS, AFC on the initiation day, proportion of type A endometrium on the hCG injection day, clinical pregnancy rate, biochemical pregnancy rate, early abortion rate, ectopic pregnancy rate) were compared. RESULTS: On the GnRH-A protocol initiation day, among all patients with different ovarian responses, the body mass index (BMI) in those with an LH ≥ 5 IU/L was lower. The differences in pregnancy outcomes between the LH < 5 IU/L group and the LH ≥ 5 IU/L group were not statistically significant across the different ovarian response groups, but the LH < 5 IU/L group had a higher proportion of good-quality embryos (80.3±24.9 vs. 74.8±26.9, P =0.035) than the LH≥5IU/Lgroup in those with poor ovarian response. The total fertilization rate (82.2±18.1 vs 85.4±15.1, P =0.021) and proportion of two pronuclei (2PN) (69.0±20.9 vs 72.7±19.9, P =0.035) were higher in the LH ≥ 5 IU/L group than the LH<5 IU/L group for those with normal ovarian responses. The embryo implantation rate (41.4±41.3 vs 52.6±43.4, P =0.012) was higher in the LH ≥ 5 IU/L group than in the LH<5 IU/L group in those with high ovarian response. The results of the multivariate logistic analysis showed that the age of the female partner, number of embryos transferred, proportion of good-quality embryos, endometrial thickness on the hCG injection day, and moderate- to-severe ovarian hyperstimulation syndrome (OHSS) were independent factors correlated with the outcome of live births (P < 0.05). CONCLUSION: The LH levels on the gonadotropins (Gn) initiation day in the GnRH-A protocol will not affect pregnancy outcomes.

Construction of a multi-scale effectiveness evaluation system for ecological restoration and protection of territorial space.

The ecological restoration and protection of territorial space is a systematic project for the protection and restoration of ecosystems damaged or degraded by human disturbance. Effectiveness evaluation is of great significance to the optimization, adjustment, and sustainability of ecological restoration and protection. Current research and practices tend to focus on a single element and the site scale. Based on the study on the connotation of ecological restoration and protection of territorial space and the multi-scale characteristics of ecosystems, we constructed a multi-scale effectiveness evaluation system for ecological restoration and protection of territorial space and a full-cycle monitoring system for effectiveness evaluation. The multi-scale effectiveness evaluation system consisted of the regional/watershed scale, the protection and restoration unit scale, and the sub-project scale. The full-cycle monitoring system contained the basic information investigation system before construction, the construction monitoring system during construction, and the multi-scale effectiveness evaluation system after construction. At the regional/watershed scale, structure, quality, and services of ecosystem were concerned and remote sensing was used as the main method to capture data. At the protection and restoration unit scale, ecological stress factors, ecosystem quality and services were concerned, and the main methods were remote sensing combined with field survey. At the sub-project scale, engineering technology measures were concerned and the field survey was used as the main method. In the implementation of the multi-scale effectiveness evaluation, it would be necessary to focus on and solve the key issues including the spillover effect, transmission mechanism, and potential impact of ecological restoration.

[Evaluation the efficacy and safety of estradiol and drospirenone tablets in the treatment of menopausal symptoms among postmenopausal Chinese healthy women:a randomized, multi-center, double-blind, placebo-controlled clinical study].

OBJECTIVE: To study the efficacy and safety of estradiol and drospirenone tablets (Angeliq) in treatment of menopausal symptoms among postmenopausal Chinese healthy women. METHODS: Total 244 postmenopausal Chinese healthy women who had moderate to severe hot flushes were randomly assigned into estradiol and drospirenone (observation group, n = 183) or placebo group (n = 61) by the ratio of 3:1 for 16 weeks in this randomized multi-center double-blind placebo-controlled study. During the trial, the follow-up visits were conducted at week 4, 8, 12, 16 of treatment and 2 weeks after treatment respectively. Height, weight, vital signs, hot flushes, other relevant menopausal symptoms and vaginal bleeding were observed in each follow-up visit, while the clinical global impression scale was assessed at 16 weeks as well. RESULTS: It showed that hot flushes were reduced significantly more in observation group than that in placebo group (P < 0.01), although both treatments were effective. The absolute values of mean severity index of total hot flushes decreased by -0.6 ± 0.5 in observation group and -0.4 ± 0.4 in placebo group from baseline respectively, which reached significant difference (P < 0.05). However, the absolute values of mean severity index of moderate to severe hot flushes decreased by -0.6 ± 0.8 in observation group and -0.3 ± 0.6 in placebo group from baseline respectively, which had no significant difference (P > 0.05). After 16 weeks treatment, it also showed that estradiol and drospirenone had significant better efficacy than placebo on moderate to severe sweating, vaginal dryness and clinical global impression scale (P < 0.01). During the trial, blood pressure in observation group was stable. The rate of vaginal bleeding in observation group was higher than that in the placebo group, especially during the week 4 to week 8 when 48.9% (87/178) in observation group and 10.7% (6/56) in placebo group of patients bled. Although the cumulative amenorrhea rate of observation group was lower than that of placebo group in each cycle (28 days), it increased gradually along with duration of the treatment. The commonest adverse event in observation group was breast tenderness which accounted for 12.0% (22/183). The level of serum potassium was in the normal range in observation group mostly.Meanwhile, the other adverse events rate was low. Serious adverse events reported in this trial were assessed as not study drug related or as unlikely study drug related. CONCLUSION: Estradiol and drospirenone tablets which could effectively alleviate menopausal symptoms in postmenopausal Chinese healthy women is a novel hormone replacement therapy regimen with high safety and efficacy.

[TG-FTIR analysis of thermal degradation of bischofite's crystals with aniline hydrochloride].

The dehydration of bischofite is the key to the use of magnesium resource. Double salts or complex method is an important way to prepare anhydrous magnesium chloride. The crystals of bischofite and aniline hydrochloride were prepared through lowering the temperature of the mixture's aquatic solution slowly. The pyrolysis of aniline hydrochloride, bischofite and the crystals was qualitatively analyzed by TG-FTIR under 400 degrees C. We infered the reaction process through qualitative detection of escaping gas of each decomposition step. The Experimental results showed that there were three steps in the thermal decomposition of bischofite. In the first step, nearly four crystallized waters decomposed, while hydrolysis and decomposition took place together in the next two steps, but hydrolysis was the main reaction at the lower temperature (205-235 degrees C), and comparative decomposition was the main one at the higher temperature (235-287 degrees C). In the experimental temperature range, aniline hydrochloride didn't decompose. Water and aniline hydrochloride left the crystals at different temperature, and no hydrolysis reaction occurred. Anhydrous magnesium chloride can be prepared though this way.

The Clinical Efficacy of Three Different Follicle-Stimulating Hormones for Follicle Growth and Development in Long-Protocol Controlled Ovarian Hyperstimulation Treatment.

OBJECTIVE: To compare the use and clinical efficacy of three different follicle-stimulating hormones (FSHs) for follicle growth and development in long-protocol controlled ovarian hyperstimulation (COH). METHODS: A total of 540 gonadotropin-releasing hormone (GnRH) agonists' long protocol treatment cycles at our hospital between January 2015 and May 2020 and met the inclusion criteria were retrospectively analyzed. The cycles were divided into three groups based on their indexes (groups A, B, and C). Each of the groups received a different type of FSH during treatment. A cross-group comparison was then undertaken to evaluate the growth and development of the three largest follicles and the patients' pregnancy-related indexes between the normal-response and high-response populations. RESULTS: In the normal-response populations, the number of high-quality embryos obtained in groups A and B was significantly higher than in group C, and the FSH dosage was significantly lower than in group C (P < 0.05). There were more follicles with a diameter of 16-18 mm found in group A than in group C on the day of hCG injection (hCG day) (P < 0.05), but there were no significant differences in the groups in other indicators. In the high-response populations, the number of oocytes retrieved and high-quality embryos obtained in group A were significantly higher than in group C (P < 0.05), and the total dosage and duration of FSH stimulation in group C were significantly higher than groups A and B (P < 0.05). CONCLUSION: Three different types of FSH led to comparable growth rates of the three largest follicles and clinical pregnancy rates per fresh cycle in long-protocol COH treatment.

Monoterpenes from Paeonia albiflora and their inhibitory activity on nitric oxide production by lipopolysaccharide-activated microglia.

Eleven new monoterpenes, paeonidangenin (1), paeonidanin A (2), paeonidanin B (3), paeonidanin C (4), paeonidanin D (5), paeonidanin E (6), paeoniflorone (7), 4-O-methylbenzoylpaeoniflorin (8), 4-O-methylgalloylpaeoniflorin (9), 4-O-methyldebenzoylpaeoniflorin (10), and 4-O-methylalbiflorin (11), were isolated from the 60% ethanol extract of the roots of Paeonia albiflora. Their structures were determined primarily on the basis of 1D and 2D NMR techniques and MS studies. Paeonidanins D (5) and E (6) are unprecedented examples of "cage-like" monoterpene dimers. The inhibitory effects of the isolated compounds on nitric oxide production by lipopolysaccharide (LPS)-activated N9 microglia were evaluated.

Comparison of inhibitory potency of three different curcuminoid pigments on nitric oxide and tumor necrosis factor production of rat primary microglia induced by lipopolysaccharide.

Microglia are the resident innate immune cells in the central nervous system. Evidence supports that the unregulated activation of microglia results in the production of pro-inflammatory cytokines and chemokines that propagate neuronal injury and finally cause neurodegenerative diseases. Curcuminn (Cur), demethoxycurcumin (DMC), and bisdemethoxycurcumin (BDMC) are curcuminoid pigments extracted from turmeric (Curcuma longa L.). Cur has been reported to suppress the activation of microglia by reducing toxic factors production, but little is known about whether the two natural demethoxy derivatives of Cur, DMC and BDMC, have the similar effects as Cur. In the present study, we found that all of the three curcuminoid pigments significantly suppressed nitric oxide (NO) production by LPS-activated microglia and the relative potency was DMC>BDMC>Cur. This result was verified by RT-PCR analysis of iNOS mRNA. The NO-scavenging abilities of three curcuminoid pigments are very weak, which suggested that the indirect effect may not be critical in inhibiting NO production by LPS-activated microglia. Moreover, these three curcuminoid pigments attenuated the expression of mRNA and proteins of tumor necrosis factor-alpha (TNF-alpha) in a concentration-dependent manner and the relative potency was also DMC>BDMC>Cur. In conclusion, Cur, DMC and BDMC were found as potent microglia-activation inhibitors, and DMC exhibited the strongest inhibitory activity on NO and TNF-alpha production. These results provided an interesting clue for designing new compounds which could have better potential therapeutic implications for various neurodegenerative diseases.

RV09, a novel resveratrol analogue, inhibits NO and TNF-alpha production by LPS-activated microglia.

Excessive activation of microglial cells has been implicated in various neurodegenerative diseases. Resveratrol, a polyphenolic compound found in grapes and wine, has been reported to reduce the activation of microglia. In the present study, 5-[2-(4-bromothiophen-2-yl)vinyl]benzene-1,3-diol (RV09), a novel resveratrol analogue, was found to suppress NO production by LPS-activated N9 microglial cell line and/or cultured rat cortical microglia. RV09 appeared to have a slight NO-scavenging activity in sodium nitroprusside (SNP) solution. The inhibition of iNOS was also observed, suggesting the blockage of transcriptional levels. Moreover, RV09 attenuated the expression of mRNA and protein of tumor necrosis factor-alpha (TNF-alpha) in a concentration-dependent manner. Further studies revealed that RV09 blocked IkappaBalpha phosphorylation and degradation, as well as reactive oxygen species (ROS) production in N9 microglial cells. It was also found that RV09 is a effective scavenger for 2,2-diphenyl-1-picrylhydrazyl (DPPH) used as a general free radical model. In the summary, these data suggest that, by blocking IkappaBalpha phosphorylation and degradation, RV09 acts to suppress the LPS-induced NO and TNF-alpha production in microglia, and this effect was mediated, at least in part, by inhibiting the generation of ROS. Our results suggested that RV09 is a novel anti-inflammatory agent which can inhibit proinflammatory responses of microglia.

Effects of resveratrol and its derivatives on lipopolysaccharide-induced microglial activation and their structure-activity relationships.

The inhibitory effects of 21 resveratrol derivatives on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in microglia and their structure-activity relationships were studied. It was found, for the first time, that certain resveratrol derivatives that have 3,5-dimethoxyl groups in the A-ring, such as (E)-4-(3,5-dimethoxystyryl)phenol (pterostilbene, compound 2), or have substituted the B-ring of resveratrol with quinolyl, such as (E)-5-[2-(quinolin-4-yl)vinyl]benzene-1,3-diol (compound 18) and (E)-4-(3,5-dimethoxystyryl)quinoline (compound 19), strongly inhibited NO production. Compounds 2, 18, and 19 reduced LPS-induced protein and mRNA expression of inducible NO synthase (iNOS), but did not display direct NO-scavenging activity up to 30 microM in sodium nitroprusside (SNP) solution. Moreover, compounds 2, 18, and 19 could also significantly inhibit the production of TNF-alpha by LPS-activated microglia. Further studies revealed that compounds 2, 18, and 19 inhibited LPS-induced NO and TNF-alpha production in microglia by blocking IkappaBalpha phosphorylation and degradation. The potent inhibitory effects of compounds 2, 18, and 19 on microglial activation suggest their potential for treatment of neurodegenerative diseases accompanied by microglial activation.

Sex-specific responses to winter flooding, spring waterlogging and post-flooding recovery in Populus deltoides.

Winter flooding events are common in some rivers and streams due to dam constructions, and flooding and waterlogging inhibit the growth of trees in riparian zones. This study investigated sex-specific morphological, physiological and ultrastructural responses to various durations of winter flooding and spring waterlogging stresses, and post-flooding recovery characteristics in Populus deltoides. There were no significant differences in the morphological, ultrastructural and the majority of physiological traits in trees subjected to medium and severe winter flooding stresses, suggesting that males and females of P. deltoides were winter flooding tolerant, and insensitive to winter flooding duration. Males were more tolerant to winter flooding stress in terms of photosynthesis and chlorophyll fluorescence than females. Females displayed greater oxidative damage due to flooding stress than males. Males developed more efficient antioxidant enzymatic systems to control reactive oxygen species. Both sexes had similarly strong post-flooding recovery capabilities in terms of plant growth, and physiological and ultrastructural parameters. However, Males had better recovery capabilities in terms of pigment content. These results increase the understanding of poplars's adaptation to winter flooding stress. They also elucidate sex-specific differences in response to flooding stress during the dormant season, and during post-flooding recovery periods.

[Effects of mifepristone of different doses on emergency contraception, a randomized double-blind study].

OBJECTIVE: To compare the effects of mifepristone of different doses on emergency contraception. METHODS: 3,052 healthy women with regular menstrual cycle who visited the 10 family planning institutes and hospitals in Beijing, Shanghai, Shangdong, Sichuan, Tianjin, Guangdong, and Liaoning for emergency contraception within the period of 120 hours after a single act of unprotected sex were given a single dose of 10 mg or 25 mg mifepristone randomly and double-blindly. They were asked to record the vaginal hemorrhage that would occur and not to have unprotected sex until the next menstrual onset when they were followed up. The trial for a specific subject ended when she menstruated. If the menstruation was irregular or a specific subject failed to menstruate on time a blood or urine human chorionic gonadotropin (hCG) test was made. If the hCG test was negative, an appointment was made to follow up once one week later. If the hCG test was positive ultrasound examination was made to detect pregnancy. If the subject still failed to menstruate and the hCG test was still negative follow-up for this subject could be finished. RESULTS: Twenty-two of the 3,052 subjects were lost to follow up. Among the remaining 3,030 women 1,516 were in the 10 mg group and 1 514 in the 25 mg group. Seventeen pregnancies occurred in each group, with a pregnancy rate of 1.1% for both groups. The relative risk of pregnancy of treatment of 25 mg mifepristone in comparison with treatment of 10 mg mifepristone was 1.0 (95% CI: 0.51-1.95). Both doses prevented about 85% approximately 86% of the anticipated pregnancy if no measure had been adopted. The pregnancy rate nearly doubled in the women who had unprotected sex after treatment of mifepristone. The efficacy of mifepristone decreased along with the delay of mifepristone administration. Side effects were uncommon and mild. Delay of 7 days or more in the onset of next menstruation occurred in 9%-10% of the women. CONCLUSION: Mifepristone of the dose of 10 mg is safe and effective for emergency contraception. Earlier administration is preferable, although the method can be used effectively up to five days after the unprotected sex.

VEGFR2 functions as an H2S-targeting receptor protein kinase with its novel Cys1045-Cys1024 disulfide bond serving as a specific molecular switch for hydrogen sulfide actions in vascular endothelial cells.

AIMS: The potential receptor for hydrogen sulfide (H2S) remains unknown. RESULTS: H2S could directly activate vascular endothelial growth factor receptor 2 (VEGFR2) and that a small interfering RNA (siRNA)-mediated knockdown of VEGFR2 inhibited H2S-induced migration of human vascular endothelial cells. H2S promoted angiogenesis in Matrigel plug assay in mice and this effect was attenuated by a VEGF receptor inhibitor. Using tandem mass spectrometry (MS), we identified a new disulfide complex located between Cys1045 and Cys1024 within VEGFR2 that was labile to H2S-mediated modification. Kinase activity of the mutant VEGFR2 (C1045A) devoid of the Cys1045-Cys1024 disulfide bond was significantly higher than wild-type VEGFR2. Transfection with vectors expressing VEGFR2 (C1045A) caused a significant increase in cell migration, while the migration-promoting effect of H2S disappeared in the cells transfected with VEGFR2 (C1045A). Therefore, the Cys1045-Cys1024 disulfide bond serves as an intrinsic inhibitory motif and functions as a molecular switch for H2S. The formation of the Cys1045-Cys1024 disulfide bond disrupted the integrity of the active conformation of VEGFR2. Breaking the Cys1045-Cys1024 disulfide bond recovered the active conformation of VEGFR2. This motif was prone to a nucleophilic attack by H2S via an interaction of their frontier molecular orbitals. siRNA-mediated knockdown of cystathionine γ-lyase attenuated migration of vascular endothelial cells induced by VEGF or moderate hypoxia. INNOVATION AND CONCLUSION: The study provides the first piece of evidence of a molecular switch in H2S-targeting receptor protein kinase in H2S-induced angiogenesis and that may be applicable to additional kinases containing functionally important disulfide bonds in mediating various H2S actions.

[Spatial variability and evaluation of soil heavy metal contamination in the urban-transect of Shanghai].

Soil heavy metal concentrations along the typical urban-transect in Shanghai were analyzed to indicate the effect of urbanization and industrialization on soil environment quality. Spatial variation structure and distribution of 5 heavy metals (Cu, Cr, Mn, Pb and Zn) in the top soil of urban-transect were analyzed. The single pollution index and the composite pollution index were used to evaluate the soil heavy metal pollution. The results showed that the average concentrations of the Cu, Pb, Zn, Cr, Mn were 27.80, 28.86, 99.36, 87.72, 556.97 mg x kg(-1), respectively. Cu, Cr, Mn, Pb and Zn were medium in variability, Mn was distributed lognormally, while Cu, Cr, Pb and Zn were distributed normally. The results of semivariance analysis showed that Mn was fit for the exponential model, Cr, Pb, Cu and Zn were fit for the linear model. The spatial distribution maps of heavy metal content of the topsoil in this city-transect were produced by means of the universal kriging interpolation. Cu was spatially distributed in ribbon, Cr and Mn were distributed in island, while the spatial distribution of Pb and Zn showed the mixed characteristic of ribbon and island. With the result of soil pollution evaluation, it showed that the pollution of Cr, Zn and Pb was relatively severe. Cr, Zn, Pb, Mn and Cu were significantly correlated, and heavy metal co-contamination existed in soil. Difference of soil heavy metals pollution along "Urban-suburban-rural" was obvious, the special variation of heavy metal concentrations in the soil closely related to the degree of industrialization and urbanization of the city.

PI3K p110α isoform-dependent Rho GTPase Rac1 activation mediates H2S-promoted endothelial cell migration via actin cytoskeleton reorganization.

Hydrogen sulfide (H(2)S) is now considered as the third gaseotransmitter, however, the signaling pathways that modulate the biomedical effect of H(2)S on endothelial cells are poorly defined. In the present study, we found in human endothelial cells that H(2)S increased cell migration rates and induced a marked reorganization of the actin cytoskeleton, which was prevented by depletion of Rac1. Pharmacologic inhibiting vascular endothelial growth factor receptor (VEGFR) and phosphoinositide 3-kinase (PI3K) both blunted the activation of Rac1 and the promotion of cell migration induced by H(2)S. Moreover, H(2)S-induced Rac1 activation was selectively dependent on the presence of the PI3K p110α isoform. Activated Rac1 by H(2)S thus in turn resulted in the phosphorylation of the F-actin polymerization modulator, cofilin. Additionally, inhibiting of extracellular signal-regulated kinase (ERK) decreased the augmented cell migration rate by H(2)S, but had no effect on Rac1 activation. These results indicate that Rac1 conveys the H(2)S signal to microfilaments inducing rearrangements of actin cytoskeleton that regulates cell migration. VEGFR-PI3K was found to be upstream pathway of Rac1, while cofilin acted as a downstream effector of Rac1. ERK was also shown to be involved in the action of H(2)S on endothelial cell migration, but independently of Rac1.

[Population, distribution and food composition of wolves (Canis lupus) at Saihanwula Nature Reserve, Inner Mongolia].

To provide initial value for population restoration and management of wolves (Canis lupus) in the wild, line transect survey and fecal analysis method were used to study the population ecology of wolf at Saihanwula National Nature Reserve, Inner Mongolia. The results revealed that the population number was at least seven within the reserve and population density was 4.18+/-2.88 individual per 100 km2. The wolf population was mainly distributed in Shengshan and Qinyunshan core areas; active sites appeared mostly along mountain ridges, roads and valleys at Shengshan and mountain ridges at Qinyunshan. Hare (Lepus capensis) and plants occurred frequently in the food composition of wolf scats. Food types varied between years but not seasons (Winter-Spring and Summer-Autumn).

The oxidative transformation of sodium arsenite at the interface of alpha-MnO2 and water.

Arsenite is acute contaminant to human health in soil and water environment. In this study, Pyrolusite (alpha-MnO(2)) was used to investigate the oxidative transformation of arsenite into arsenate with batch experiments under different reaction conditions. The results showed that arsenite transformation occurred and was accompanied by the adsorption and fixation of both As(III) and As(V) on alpha-MnO(2). About 90% of sodium arsenite (10mg/L) were transformed by alpha-MnO(2) under the conditions of 25 degrees C and pH 6.0, 36.6% of which was adsorbed and 28.9% fixed by alpha-MnO(2). Increased alpha-MnO(2) dosages promoted As (III) transformation rate and adsorption of arsenic species. The transformation rate and adsorption of arsenic species raised with increasing pH values of reaction solution from 4.7 to 8.0. The oxidation rate decreased and adsorbed As(III) and As(V) increased with increasing initial arsenite concentration. The enhancement on oxidative transformation of sodium arsenite may result from abundant active sites of alpha-MnO(2). Along with adsorption and fixation of arsenic species during the reaction, the crystal structure of alpha-MnO(2) did not change, but the surface turned petty and loosen. Our results demonstrated that alpha-MnO(2) has important potential in arsenic transformation and removal as the environmentally friendly natural oxidant in soil and surface water.

Anti-inflammatory effects of rhynchophylline and isorhynchophylline in mouse N9 microglial cells and the molecular mechanism.

Excessive production of nitric oxide (NO) and proinflammatory cytokines from activated microglia contributes to human neurodegenerative disorders. Our previous study demonstrated the potent inhibition of lipopolysaccharide (LPS)-induced NO production in rat primary microglial cells by rhynchophylline (RIN) and isorhynchophylline (IRN), a pair of isomeric alkaloids of Uncaria rhynchophylla (Miq.) Jacks. that has been used in China for centuries as a "cognitive enhancer" as well as to treat strokes. We further investigated whether RIN and IRN effectively suppress release of proinflammatory cytokines in LPS-activated microglial cells and the underling molecular mechanism for the inhibition of microglial activation. RIN and IRN concentration-dependently attenuated LPS-induced production of proinflammatory cytokines such as TNF-alpha and IL-1beta as well as NO in mouse N9 microglial cells, with IRN showing more potent inhibition of microglial activation. The western blotting analysis indicated that the potential molecular mechanism for RIN or IRN-mediated attenuation was implicated in suppressions of iNOS protein level, phosphorylation of ERK and p38 MAPKs, and degradation of IkappaBalpha. In addition, the differential regulation of the three signaling pathways by two isomers was shown. Our results suggest that RIN and IRN may be effective therapeutic candidates for use in the treatment of neurodegenerative diseases accompanied by microglial activation.