Mevalonate improves anti-PD-1/PD-L1 efficacy by stabilizing CD274 mRNA

Mevalonate metabolism plays an important role in regulating tumor growth and progression; however, its role in immune evasion and immune checkpoint modulation remains unclear. Here, we found that non-small cell lung cancer (NSCLC) patients with higher plasma mevalonate response better to anti-PD-(L)1 therapy, as indicated by prolonged progression-free survival and overall survival. Plasma mevalonate levels were positively correlated with programmed death ligand-1 (PD-L1) expression in tumor tissues. In NSCLC cell lines and patient-derived cells, supplementation of mevalonate significantly up-regulated the expression of PD-L1, whereas deprivation of mevalonate reduced PD-L1 expression. Mevalonate increased CD274 mRNA level but did not affect CD274 transcription. Further, we confirmed that mevalonate improved CD274 mRNA stability. Mevalonate promoted the affinity of the AU-rich element-binding protein HuR to the 3'-UTR regions of CD274 mRNA and thereby stabilized CD274 mRNA. By in vivo study, we further confirmed that mevalonate addition enhanced the anti-tumor effect of anti-PD-L1, increased the infiltration of CD8+ T cells, and improved cytotoxic function of T cells. Collectively, our findings discovered plasma mevalonate levels positively correlated with the therapeutic efficacy of anti-PD-(L)1 antibody, and provided the evidence that mevalonate supplementation could be an immunosensitizer in NSCLC.

The impact of lipids on the cancer-immunity cycle and strategies for modulating lipid metabolism to improve cancer immunotherapy

Lipids have been found to modulate tumor biology, including proliferation, survival, and metastasis. With the new understanding of tumor immune escape that has developed in recent years, the influence of lipids on the cancer-immunity cycle has also been gradually discovered. First, regarding antigen presentation, cholesterol prevents tumor antigens from being identified by antigen presenting cells. Fatty acids reduce the expression of major histocompatibility complex class I and costimulatory factors in dendritic cells, impairing antigen presentation to T cells. Prostaglandin E2 (PGE2) reduce the accumulation of tumor-infiltrating dendritic cells. Regarding T-cell priming and activation, cholesterol destroys the structure of the T-cell receptor and reduces immunodetection. In contrast, cholesterol also promotes T-cell receptor clustering and relative signal transduction. PGE2 represses T-cell proliferation. Finally, regarding T-cell killing of cancer cells, PGE2 and cholesterol weaken granule-dependent cytotoxicity. Moreover, fatty acids, cholesterol, and PGE2 can improve the activity of immunosuppressive cells, increase the expression of immune checkpoints and promote the secretion of immunosuppressive cytokines. Given the regulatory role of lipids in the cancer-immunity cycle, drugs that modulate fatty acids, cholesterol and PGE2 have been envisioned as effective way in restoring antitumor immunity and synergizing with immunotherapy. These strategies have been studied in both preclinical and clinical studies.

Erratum: Author correction to 'Mevalonate improves anti-PD-1/PD-L1 efficacy by stabilizing CD274 mRNA' Acta Pharmaceutica Sinica B 13 (2023) 2585-2600

[This corrects the article DOI: 10.1016/j.apsb.2023.04.002.].

Effects of propofol treatment on neuroapoptosis in primary cultured cortical neurons / 临床麻醉学杂志

Objective To investigate the effect of propofol exposure on neuroapoptosis in pri-mary cultured cortical neurons and its mechanisms.Methods Cortical neurons were primarily cultured for seven days,then divided into two groups:control group (treated with equal volume of 20% in-tralipid),propofol-treated group (treated with 500 μmol/L propofol).The neurons were treated for 12 h.The neuron viability was determined by MTT.Neuroapoptosis was identified by Hoechest 33 258 dying.Mitochondrial membrane potential was measured by the fluorescent dye rhodamine 123 (Rh123).Western blot was performed to detect the level of cyt-c and cleaved-caspase-3.Results Neu-rons survival rate (54.4%±6.4%)in the propofol group was significantly lower than that of control group (99.8% ± 4.1%) (P < 0.05 ), the rate of neuronal apoptosis (46.5% ± 5.3%) was significantly higher than that of control group (7.2%±0.9%)(P <0.05),mitochondrial membrane potential (59.6%±4.3%)was significantly lower than that of the control group (99.9% ± 5.7%) (P <0.05 ),cyt-C protein level (0.38 ± 0.03 )was significantly higher than that of control group (0.1 5±0.02)(P < 0.05 ),level of cleaved-caspase-3 protein level (0.46 ± 0.04)was significantly higher than that of control group (0.13±0.02)(P <0.05).Conclusion Propofol induces neuroapo-tosis in primary cultured cortical neurons,which is associated with the decreased level of MPP and the increase levels of cyt-c and cleaved-caspase-3.

Effects of 17β-estradiol on propofol-induced rat cortical neuroapoptosis / 中国比较医学杂志

Objective To investigate the protective effects and the mechanisms of 17β-estradiol on the propofol-induced neuroapoptosis in primary cultured rat cortical neurons.Methods The neurons were cultured for 7 days and then divided into three groups: vehicle-control group ( treated with equal volume of 20% intralipid ) , propofol-treated group ( treated with 500μmol/L propofol) , and propofol plus 17β-estradiol treated group ( treated with 500μmol/L propofol and 0.1 μmol/L 17β-estradiol).12 hours after the treatment, neuroapoptosis was detected by Hoechst 33258 staining and TUNEL assay, and the levels of Bcl-2, Bax and cleaved caspase-3 proteins were detected by Western blot.Results Compared with the vehicle-control group, the neuroapoptosis increased greatly ( P<0.01 ) , Bcl-2 level reduced ( P <0.01), Bax and cleaved caspase-3 levels increased greatly (P<0.01), and Bcl-2/Bax ratio reduced significantly (P<0.01).Compared with the propofol-treatment group, the neuroapoptosis decreased greatly ( P <0.01), Bcl-2 level increased ( P<0.01 ) , Bax and cleaved caspase-3 levels reduced greatly ( P <0.01 ) , and Bcl-2/Bax ratio increased greatly ( P <0.01 ) . Conclusions 17β-estradiol can protect cortical neurons against propofol-induced cortical neuroapoptosis by regulating the expression of Bcl-2 and Bax.

Effect and mechanism of dexmedetomidine on propofol-induced apoptosis of cortical neurons in rats / 中华行为医学与脑科学杂志

Objective To investigate the mechanisms of the protective effects of dexmedetomidine against the propofol-induced neuroapoptosis in primary cultured cortical neurons.Methods The neurons were cultured 7days and then divided into four groups: vehicle-control group (treated with equal volume of intralipid), propofoltreated group (treated with 500 μmol/L propofol), propofol plus dexmedetomidine treated group (treated with 500 μmol/L propofol and 0.1 μmol/L dexmedetomidine), and LY294002 pretreated group (treated with 500 μmol/L propofol ,0.1 μ mol/L dexmedetomidine and 10 μmol/L LY294002).12 hours after different treatments, neuron viability was measured by MTT assay,neuroapoptosis was detected by Hoechst33258 staining, and the levels of pAkt and Bcl-2 protein were detected by Western blot.Results Compared with the vehicle-reduced group,propofol reduced neuron viability greatly((53.4±4.2)％ vs (99.9±6.3)％;P＜0.01), but increased neuroapoptosis greatly((44.6±4.3)％ vs (5.8±0.4)％;P＜0.01).The levels of pAkt((0.41±0.03) vs (0.86±0.07))and Bcl-2 ((0.15±0.02) vs (0.72±0.03)) were decreased greatly (both P＜0.01).Compared with propofol treatment group, the neuron viability of propofol plus dexmedetomidine group were increased greatly((86.4±5.3) ％ , P＜0.01) ,the neu roapoptosis was decreased greatly ((23.1 ± 3.5) ％, P＜ 0.01), and the levels of pA kt (0.8 ± 0.03) and Bc1-2 (0.52 ±0.05) were increased greatly (both P＜0.01).Compared with propofol plus dexmedetomidine treated group,LY294002 inhibited the protective effects of dexmedetomidine, decreased neuron viability greatly ((64.3±5.1) ％ ,P＜0.01), increased the number of apoptotic neurons((38.8±4.9) ％, P＜0.01), and reduced the levels of pAkt (0.52±0.04) and Bcl-2(0.31±0.02) significantly (P＜0.01).Conclusion Dexmedetomidine exerts the neuroprotective effects against propofol-induced neuroapoptosis by activating the PI3K-Akt-Bcl-2 signalling pathway.

Dexmedetomidine protects cortical neurons from ketamine-induced apoptosis by activating the PI3 K-Akt signaling pathway / 医学研究生学报

Objective Dexmedetomidine is known to have a neuroprotective effect.The aim of this study was to investigate the effects of dexmedetomidine on ketamine-induced apoptosis of primarily cultured cortical neurons and its action mechanisms. Methods Rat cortical neurons were primarily cultured for 7 days and treated with ketamine (100μmol/L) and different concentrations of dexmedetomi-dine (0.001, 0.01, 0.1, and 1 μmol/L) for 24 hours, followed by measurement of the viability of the neurons by MTT assay.The neurons were divided into four groups:vehicle control, ketamine ( trea-ted with 100 μmol/L ketamine), dexmedetomidine+ketamine (DD+K, treated with 0.1 μmol/L DD and 100 μmol/L ketamine), and LY294002 ( treated with 0.1 μmol/L DD, 100 μmol/L ketamine, and 10 μmol/L LY294002) .After 24 hours of treatment, the apoptosis rate of the neurons was determined by Hoechst33258 staining, and the expressions of pAkt and cleaved-caspase-3 in the neu-rons detected by Western blot. Results The apoptosis rate of neurons was dramatically increased in the LY294002 and ketamine groups in comparison with the vehicle control and DD+K groups ([36.8 ±4.4] and [43.4 ±4.5]%vs [7.5 ±1.1] and [16.4 ± 3.6]%, P<0.01), the pAkt level remarkably decreased (0.26 ±0.02 and 0.15 ±0.01 vs 0.61 ±0.05 and 0.50 ±0.04, P<0.01), and the expression of cleaved caspase-3 significantly upregulated in the former two as compared with the latter two groups (0.40 ±0.02 and 0.65 ±0.03 vs 0.10 ±0.02 and 0.12 ±0.01, P<0.01). Conclusion Dexmedetomidine exerts a neuroprotec-tive effect against ketamine-induced apoptosis of neurons by activating the PI3K-Akt signaling pathway.

Effect of 17β-estradiol on ketamine-induced long-term cognitive deficits in developing rats / 中华行为医学与脑科学杂志

Objective To investigate the effect of 17β-estradiol on ketamine-induced long-term cognitive deficits in neonatal rats.Methods 80 SD male rats aged 7 days were randomly divided into group C,V,E,K and K+E,and 16 per group.Group C was intraperitoneally injected with same volume of saline for three consecutive days,Group V was subcutaneously injected with same volume of sesame oil for three consecutive days,Group E was subcutaneously injected with 600 μg · kg-1 17β-estradiol for three consecutive days,group K was intraperitoneally injected with 75 mg · kg-1 ketamine for three consecutive days,group K+E was intraperitoneally injected with 75 mg · kg-1 ketamine in combination with 600 μg · kg-1 17β-estradiol injected subcutaneously for three consecutive days.At 2 months of age,learning and memory abilities were tested with the Mortis water maze.After Morris water naze test,ten rats from each group were decapitated and the prefrontal cortex (PFC) was isolated to detect acetylcholine esterase(AchE) activity with ELISA assay and to measure acetylcholine(Ach) level by hydroxylammonium chloride method.Results The escape latency ((40.26±2.36) s,(30.25±2.20) s,(21.55±2.42) s) and path length((1019.35±58.13) cm,(811.16±27.58) cm,(598.34±34.74) cm) of group K were more than those of group C on the third,fourth aud fifth training days (all P＜0.05),while escape latency ((29.46±2.20) s,(24.86± 2.14) s,(17.20±1.91) s) and path length((913.90±41.89) cm,(729.42±31.36) cm,(487.64±18.61)cm) of group K+E were significantly lower than those of group K(all P＜0.05).On test day 6,rats were subjected to a probe trial,ratio of time spent in the target quadrant ((24.5±2.7) ％) and the number of crossings over previous platform locations (1.9±0.5) in group K were fewer than those of group C (all P＜0.05),while ratio of time spent iu the target quadrant((42.3±3.0) ％) and the number of crossings over previous platform locations(3.5±0.5) of group K+E were more than those of group K (all P＜0.05).The AchE activity((0.69±0.04) U · mg pro-1) in rats PFC of group K was significantly higher than that of group C ((0.52±0.06) U · mg pro-1) (P＜0.05).The AchE activity of group K +E ((0.58±0.12)U · mg pro-1) was lower than that of group K(P＜0.05).The Ach level ((2.59±0.34)mg · g-1) in rats PFC of group K was significantly lower than that of group C ((4.35±0.56) mg · g-1) (P＜0.05).The Ach level of group K+E((3.88±0.61) mg · g-1) was higher than that of group K(P＜0.05).Conclusions These results indicate that ketamine impairs learning and memory abilities as rat matures,while 17β-estradiol treatment improves these impairments by inhibiting AchE activity and increasing Ach level.

Protective effect of 17β-estradiol against propofol-induced apoptosis of primarily cultured cortical neurons / 医学研究生学报

Objective 17β-estradiol is known to have a neuroprotective effect.The aim of this study was to investigate the effects of 17β-estradiol on propofol-induced neuroapoptosis in primarily cultured cortical neurons. Methods Rat cortical neurons were primarily cultured for 7 days and randomly divided into groups A ( vehicle control) , B, and C, treated with equal volume of 20%intralipid, 500 μmol/L propofol, and 500 μmol/L propofol +0.1 μmol/L 17β-estradiol, respectively.At 12 hours after treatment, the morphology of the neurons was observed under the microscope, their survival rate calculated by MTT, their apoptosis was deter-mined by FCM assay, and their mitochondrial membrane potential measured by fluorescent dye rhodamine 123. Results Compared with group A, group B showed a significantly reduced number of neurons, lack of 3-dimensional appearance, unclear contour, and fractured neuron axons, but a remarkable improvement was observed in the propofol-induced morphological damage in group C.The survival rate of the neurons and the mitochondrial membrane potential were markedly decreased in group B ([52.3 ±5.2]% and [59.1 ± 5.3]%) as compared with groups A ( [99.9 ±3.6]%and [99.6 ± 5.8]%) and C ([90.1 ±7.2]%and [89.2 ±7.1]%) (both P<0.01 ) , while the rate of neuroapoptosis significantly increased in group B ([43.4 ±4.6]%) in comparison with A ([3.1 ±0.2]%) and C ([22.3 ±3.2]%) (both P<0.01). Conclusion 17β-es-tradiol can protect against propofol-induced apoptosis of primarily cul-tured neurons by inhibiting the reduction of their mitochondrial membrane potential.

In vivo tracking of PKH26-labeled human umbilical cord mesenchymal stem cells after transplantation into rats with liver cirrhosis / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To observe the in vivo migration of human umbilical cord mesenchymal stem cells (hUCMSCs) labeled with the PKH26 red fluorescent dye after transplantation into rats with liver cirrhosis.</p><p><b>METHODS</b>Frozen hUCMSCs were resuscitated and labeled with PKH26. Labeling efficiency and fluorescent maintenance time of the PKH26-1abeled cells were measured. Morphology of the labeled and unlabeled (control) cells was observed by microscopy. The cell growth curve was determined using the MTT method. The PKH26-1abeled hUCMSCs were transplanted via tail vein injection into healthy (control) rats and rats with liver cirrhosis. Migration of the PKH26-1abeled hUCMSCs observed 48 h later in frozen liver sections under a fluorescence microscope.</p><p><b>RESULTS</b>The labeling ratio of PKH26 to hUCMSCs was 100%. Growth of the labeled cells was good. The cell morphology was not significantly different between the labeled and unlabeled cells; all cells were long and spindle-like. Cell proliferation was not impacted significantly by labeling.Fluorescence was maintained for at least 20 days, as detected by in vitro analysis. After transplantation into the rats, the PKH26-1abeled hUCMSCs were mainly distributed in the area surrounding the portal vein, the blood vessels, and the false lobule of the cirrhotic liver; a small amount ofhUCMSCs were present in the spleen and lung.</p><p><b>CONCLUSION</b>PKH26 is an ideal fluorescent dye to label hUCMSCs. The PKH26 labeling technique can be used to study the migration of hUCMSCs in cirrhotic liver.</p>

Effects of 17β-estradiol on Ketamine-induced Neuroapoptosis / 医药导报

Objective To investigate the protective effect and the mechanisms of 17β-estradiol on ketamine-induced apoptosis on primary cultured rat cortical neurons. Methods Cortical neurons were primarily cultured for seven days,then divided into four groups :control group ( treated with equal valume of DMSO ),estradiol-treated group ( treated with 0.1 μmol·L-1 17β-estradiol),ketamine-treated group(treated with 100 μmol·L-1 ketamine),ketamine plus 17β-estradiol-treated group( treated with 0. 1 μmol·L-1 17β-estradiol+100μmol·L-1 ketamine). The neurons were treated for 24 hours. The neuron viability was determined by MTT. Neuroapoptosis was measured by nuclear morphometry after Hoechest 33258 dying. Western blotting was performed to detect the expression levels of cleaved-caspase-3 and Bcl-2protein. Results The neuron viability in the ketamine group was(54. 02±7. 78)%,significantly decreased from the control group,whereas ketamine plus 17β-estradiol increased the cell viability to(88. 09±6. 54)%,significantly higher than the ketamine group. The neuroapoptosis rate in the ketamine group was(49. 50±4. 34)%,significantly increased from the control group,while that in the drug combination group was(15. 74 ± 3. 40)%,significantly lower compared with the ketamine group. Meanwhile,the cleaved-caspase-3 expression increased,and Bcl-2 expression decreased remarkably after ketamine treatment,while which was reversed in the drug combination group. Conclusion 17β-estradiol can protect against ketamine-induced injury by inhibiting neuron apoptosis.

Progesterone protects neurons against impairment induced by Aβactivated astrocytes / 中国药理学通报

Aim To investigate the effect of progester-one ( PROG) in protecting the neurons against impair-ment induced by the Aβ1-42 activated astrocytes, and the underlying molecular mechanism. Methods The astrocytes were divided into 5 groups: control, Aβ, and Aβplus PROG groups treated with 3 different con-centrations of progesterone for 24h. Then, Aβand pro-gesterone were removed, and neurons were co-cultured with the treated astrocytes. MTT assay was used to e-valuate the viability of cultured neurons; ELISA was used to detect the levels of IL-1βand TNF-αin culture media of astrocytes; immunofluorescence and Western blot were performed to detect the activation of NF-κB in astrocytes. Results PROG dose dependently pro-tected against Aβ1-42 activated astrocytes induced via-bility decrease in co-cultured neurons. Aβ induced release of IL-1β and TNF-α from astrocytes, and in-crease of NF-κB activity was abolished by progesterone treatment. Conclusion PROG protects the neurons through inhibiting the reactivity of astrocytes, and the underlying mechanism involves the NF-κB signal trans-duction.

Effects of dehydroepiandrosterone on amino acids receptor subunit NR2B and GBR1 expressed in primary cultured rat cerebral cortical neurons / 中国药理学通报

Aim To investigate the effect of dehydroepiandrosterone(DHEA)on the levels of NR2B and GBR1 expressed in primary cultured rat cerebral cortical neurons.Methods Primary cultured rat cerebral cortical neurons were treated with DHEA of different concentrations (1,10,100 μmol·L~(-1))and the expression of amino acids receptor subunit NR2B and GBR1 were detected by immunocytochemistry.Results Compared with control group,the expression intensity of NR2B increased by 15.6%,19.9% and 49.4% after DHEA-L,DHEA-M and DHEA-H treatment(P<0.05 or P<0.01);the expression intensity of GBR1 increased by 14.5% and 58.5% after DHEA-M and DHEA-H treatment(P<0.05 or P<0.01).Conclusion DHEA can enhance the expression of neuron receptor subunit NR2B and GBR1.

Naringenin inhibits the upregulation of CYP 3A4 and attenuates the cellular toxicity induced by rifampicin and isoniazid in hepatocytes / 中国药理学通报

Aim To investigate the protective effect of naringenin on isoniazid and rifampicin induced hepatotoxicity and the role of CYP 3A4.Methods Isoniazid and rifampicin were added to culture media for QSG-7701 cells and cultured for 48 hours. Narringenin, 1,5 and 25 mg·L~(-1) in final concentration,was added concomitant with isoniazid and rifampicin. The culture media and cells were collected and the activities of lactate dehydrogenase were detected with chromatometry. The ratio of extra/intracellular lactate dehydrogenase was calculated as the release rate of lactate dehydrogenase. Cells were incubated with midazolam for 2 hours after treatment with durgs and the concentration of midazolam in the incubation media was determined with HPLC-MS.Results Compared with control group, isoniazid and rifampicin treatment increased lactate dehydrogenase release and CYP 3A4 activity significantly. Naringenin attenuated the effect of isoniazid and rifampicin on lactate dehydrogenase and CYP 3A4 activity.Conclusion Naringenin can attenuate the hepatotoxicity of isoniazid and rifampicin through inhibiting the activity of CYP 3A4 in cultured hepatocytes.

Change in brain neurosteroid level of rats in morphine addiction and stress-induced addiction relapse condition / 中国药理学与毒理学杂志

AIM To investigate if morphine addiction and relapse to morphine-seeking is related to the change in neurosteroid levels in the brain of rats. METHODS Rats were injected ip morphine (5 mg·kg-1·d-1, 18:00-20:00) and trained in conditioned place preference (CPP) box, once daily for 10 d. CPP test was performed 24 h after the last training. After discontinuation of training for 7 d for CPP extinction, then intermittent and inescapable foot-shock (FS, 0.5 mA, 0.5 s on, 40 s off, 15 min) was applied to rats as the priming stimuli for relapse. CPP test was performed 2 h after FS. When CPP test finished, rats were decapitated and the levels of neurosteroids were analyzed using gas chromatography/mass spectrometry. RESULTS CPP was established when rats were injected morphine and trained for 10 d. At the same time, the levels of pregnenolone and allopregnanolone in the brain tissues of rats were significantly increased. When CPP was reinstated in morphine-treated rats by FS-stress after 7 d CPP extinction, the levels of dehydroepiandrosterone and dehydroepiandrosterone sulfate were significantly increased. CONCLUSIONThe development of morphine addiction and relapse may be related to endogenous neurosteroids in rat brain tissues.

Effects of morphine dependence and withdrawal on neurosteroids and amino acid transmitters of rat amygdala / 解放军医学杂志

Objective To investigate the effects of morphine dependence and withdrawal on neurosteroids and amino acid transmitters of rat amygdala. Methods Morphine dependence was induced by pretreatment with increasing doses of morphine for 7 days. Withdrawal was precipitated by naloxone (2mg/kg). Withdrawal syndromes were observed and scored. After decapitation, amygdala was dissected out. Nomadic and conjugated neurosteroids were extracted using liquid-liquid extraction and solid phase extraction. Concentrations of neurosteroids including dehydroepiandrosterone (DHEA), pregnenolone (PREG), allopregnanolone (AP), dehydroepiandrosterone sulfate (DHEAS) and pregnenolone sulfate (PREGS) were detected with HPLC-MS. Concentrations of glycine (GLY), glutamate (GLU) and gamma-aminobutyric acid (GABA) were quantitated by HPLC-ECD with pre-column OPA derivatization. Results Compared with saline control, the DHEA level in rat amygdala of morphine dependent group decreased by 33% (P＜0.01). Compared with naloxone control, the PREG and AP levels in rat amygdala of morphine withdrawal group increased by 45% (P＜0.05) and 42% (P＜0.05) respectively; the GABA level decreased by 18% (P＜0.01). Compared with morphine dependent group, the PREG and PREGS levels in rat amygdala of morphine withdrawal group increased by 60% and 40% respectively (P＜0.05); the glycine level decreased by 14% (P＜0.05). Conclusion The DHEA in rat amygdala may play a role in the development of morphine dependence but not involved in the manifestation of withdrawal symptoms. Other neurosteroids (including PREG, AP and PREGS) in rat amygdala seem to be involved in withdrawal but not in dependence. The synthesis and release of inhibitory amino acids in amygdala were depressed when withdrawal was precipitated by naloxone. The results suggest that different changes of neurosteroids and amino acids exist in stages of morphine dependence and withdrawal.

Effects of progesterone on morphine-induced conditioned place preference and levels of endogenous opioid peptides in hypothalamus of rat brain / 中国药理学通报

Aim To investigate the effects of progesterone on morphine rewarding effect and levels of endogenous opioid peptides in hypothalamus of rat brain. Methods Conditioned place preference(CPP)test was used to investigate the morphine rewarding effect, and radioimmunoassay (RIA) was established to deter-mine levels of ?-endorphin(?-EP), leu-enkephalin(L-EK) and dynorphin A(DynA) in hypothalamus of rat brain.Results Compared with NS control group, 5 mg?kg-1 morphine successfully induced the formation of CPP(P

Effects of GLU and GABA on the genesis of neurosteroids in primary cultured astrocytes / 中国药理学通报

Aim To investigate effects of glutamate(GLU) and ?-aminobutyric acid(GABA) on levels of neurosteroids synthesized and released by primary cultured rat brain cortical astrocytes.Methods Primary cultured rat brain cortical astrocytes were treated with GLU or GABA for 48 h respectively.Unconjugated(dehydroepiandrosterone,DHEA;pregnenolone,PREG;allopregnanolone,AP) and conjugated neurosteroids(dehydroepiandrosterone sulfate,DHEAS;pregnenolone sulfate,PREGS) in culture media were extracted by solid phase extraction(SPE) and analyzed by HPLC-MS.Results Compared with saline control group,GLU treatment decreased PREG and PREGS levels and increased DHEAS level significantly;GABA treatment decreased PREG level and increased AP level significantly.Conclusion Both GLU and GABA were shown to inhibit the genesis of PREG.While GLU significantly promoted the genesis of DHEAS and GABA promoted the genesis of AP.The genesis of PREGS was also inhibited by GLU treatment in primary cultured cortical astrocytes.

The Effect of Morphine Dependence and Withdrawal on the Levels of Neurosteroids in Hippocampus of Male Rat / 中国心理卫生杂志

Objective: To investigate the effect of morphine dependence and withdrawal on the levels of neurosteroids in hippocampus of male rat.Methods: Rats were given (ip) increasing doses of morphine to form morphine physical dependence, withdrawal syndromes were precipitated by naloxone. The conditioned place preference (CPP) was used to establish morphine psychological dependence. The concentrations of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), pregnenolone (PREG), pregnenolone sulfate (PREGS), and allopregnanolone (AP) in rat hippocampus and plasma were quantified by liquid chromatography-mass spectrometry. Results:The rat model of morphine physical and psychological dependence were successfully established by ip increasing doses of morphine for 7 days and 5mg?kg~ -1 morphine for 10 days respectively. Compared with saline control group, morphine physical dependence increased DHEA and PREG contents in rat hippocampus (0.88?0.19/0.67?0.17,t=2.52,10.94?2.02/7.53?2.64,t=3.24,P

Effect of morphine dependence on the levels of neurosteroids and amino acid transmitters in rat nucleus accumbens / 中国药理学通报

Aim To detect the effect of morphine dependence and withdrawal on the levels of neurosteroids and amino acid neurotransmitters in nucleus accumbens in rat morphine dependent model. Methods Nucleus accumbens was dissected out from morphine dependent and naloxone precipitated withdrawal rats. The contents of neurosteroids including dehydroepiandrosterone, pregnenolone, allopregnanolone, dehydroepiandrosterone sulfate and pregnenolone sulfate were detected with liquid chromatography-negative atmospheric pressure with ionization mass spectrometry(LC-MS). The contents of glycine, glutamate and ?-aminobutyric acid were quantitated by HPLC-ECD with precolumn derivatization. Results Compared with saline group,in nucleus accumbens of morphine withdrawal rats, the level of dehydroepiandrosterone sulfate (P