Antidepressant effects of curcumin in the forced swim test and olfactory bulbectomy models of depression in rats

Curcuma longa is a major constituent of Xiaoyao-san, the traditional Chinese medicinal formula, which has been used to effectively manage stress and depression-related disorders in China. Curcumin is the active component of curcuma longa, and we hypothesized that curcumin would have an influence on depressive-like behaviors. The purpose of the present study was to confirm the putative antidepressant effect of chronic administrations of curcumin (1.25, 2.5, 5 and 10 mg/kg, p.o.) in the forced swimming test and bilateral olfactory bulbectomy (OB) models of depression in rats. In the first study, chronic treatment with curcumin (14 days) reduced the immobility time in the forced swimming test. In the second experiment, curcumin reversed the OB-induced behavioral abnormalities such as hyperactivity in the open field, as well as deficits in step-down passive avoidance. In addition, OB-induced low levels of serotonin (5-HT), noradrenaline (NA), high 5-hydroxyindoleacetic acid (5-HIAA) and 4-dihydroxyphenylacetic acid (DOPAC) in the hippocampus were observed, and were completely reversed by curcumin administration. A slight decrease in 5-HT, NA and dopamine (DA) levels was found in the frontal cortex of OB rats which was also reversed by curcumin treatment. These results confirm the antidepressant effects of curcumin in the forced swim and the OB models of depression in rats, and suggest that these antidepressant effects may be mediated by actions in the central monoaminergic neurotransmitter systems.     

Antidepressant effects of curcumin in the forced swim test and olfactory bulbectomy model of depression in rats

AIM： Curcuma longa is a major constituent of Xiaoyao-san, the traditional Chinese medicinal formula, which has been used to effectively manage stress and depression-related disorders in China. Curcumin is the active component of curcuma longa, and we hypothesized that curcumin would have an influence on depressive - like behaviors and bilateral olfactory bulbectomy （OB） models of depression in rats.     

Antidepressant activity of curcumin: involvement of serotonin and dopamine system

Rationale  Curcumin is a major active principle of Curcuma longa, one of the widely used preparations in the Indian system of medicine. It is known for its diverse biological actions. Objective  The present study was designed to investigate the involvement of monoaminergic system(s) in the antidepressant activity of curcumin and the effect of piperine, a bioavailability enhancer, on the bioavailability and biological effects of curcumin. Methods and observations  Behavioral (forced swim test), biochemical (monoamine oxidase (MAO) enzyme inhibitory activity), and neurochemical (neurotransmitter levels estimation) tests were carried out. Curcumin (10–80 mg/kg, i.p.) dose dependently inhibited the immobility period, increased serotonin (5-hydroxytryptamine, 5-HT) as well as dopamine levels (at higher doses), and inhibited the monoamine oxidase enzymes (both MAO-A and MAO-B, higher doses) in mice. Curcumin (20 mg/kg, i.p.) enhanced the anti-immobility effect of subthreshold doses of various antidepressant drugs like fluoxetine, venlafaxine, or bupropion. However, no significant change in the anti-immobility effect of imipramine and desipramine was observed. Furthermore, combination of subthreshold dose of curcumin and various antidepressant drugs resulted in synergistic increase in serotonin (5-HT) levels as compared to their effect per se. There was no change in the norepinephrine levels. The coadministration of piperine (2.5 mg/kg, i.p.), a bioavailability enhancing agent, with curcumin (20 and 40 mg/kg, i.p.) resulted in potentiation of pharmacological, biochemical, and neurochemical activities. Conclusion  The study provides evidences for mechanism-based antidepressant actions of curcumin. The coadministration of curcumin along with piperine may prove to be a useful and potent natural antidepressant approach in the management of depression.     

Antidepressant effects of flupenthixol.

Strong evidence exists that flupenthixol, not presently distributed in the United States, is an effective antidepressant. Its advantages over available antidepressants include its safety with respect to overdose and in combination with other medications, low dependency risk, rapid onset of action, and availability in depot preparation. Flupenthixol also may be useful as a mood elevator for schizophrenics, an alternative mood stabilizer for patients with bipolar disease, and a facilitator for cocaine withdrawal.     

Development of differential tolerance to the sedative and anti-stress effects of benzodiazepines

Differential degree of tolerance has been reported to develop for anticonvulsant, sedative and skeletal muscle relaxant effects of benzodiazepines (BZDs). Acute treatment with BZDs reportedly reduces the formation of gastric stress ulcers and attenuates stress-induced immunosuppression. The present study investigates whether tolerance develops to these antistress effects of BZDs by using diazepam and chlordiazepoxide as representative drugs. A single dose of diazepam (5 mg/kg, i.p.) or chlordiazepoxide (20 mg/kg, i.p.) produced a significant reduction in locomotor activity, a measure of sedative effect and antagonized the effect of restraint stress (RS) on gastric mucosal lesions and anti-sheep red blood cell (SRBC) antibody titre. With chronic treatment (X 7 d), there was a marked tolerance to the sedative effect of both the studied BZD drugs, while much less tolerance developed to their ulcer protective action. However, no tolerance was observed to the attenuating effect of diazepam and chlordiazepoxide on RS-induced immunosuppression. Thus, the results of the present study indicate that different mechanisms may be involved in the development of tolerance to the sedative, antiulcer and immunomodulatory effects of BZDs.     

Sigma-receptor ligands and anti-stress actions

The functional role of sigma receptors in the central nervous system has been investigated extensively. Sigma1-receptors have been shown to play an important role in antidepressive effects since selective sigma1-receptor agonists, as well as typical antidepressants, reduced the immobility time in the forced swimming and tail suspension tests. The reduction of immobility by sigma1-receptor agonists is antagonized by NE-100, a sigma1-receptor antagonist. It has been suggested that sigma receptors are involved in anxiety since Lu 28-179, a sigma2-receptor agonist, has anxiolytic properties in rodents. In addition to the depressive animal model, phenytoin-sensitive sigma1-receptor agonists such as (+)-SKF-10,047 and dextromethorphan attenuate the conditioned fear stress (CFS) response (which is not influenced by typical anxiolytics and antidepressants) in rodents, the attenuating effects being mediated through phenytoin-sensitive sigma1 receptors, which are closely connected to the mesolimbic dopaminergic systems. Furthermore, neurosteroids such as dehydroepiandrosterone sulfate also attenuate the CFS response, the effect being mediated via sigma1 receptors. These findings suggest that sigma receptors are involved in stress-induced pathophysiological changes such as depression and anxiety and that phenytoin-sensitive sigma1-receptor ligands are useful for the treatment of affective disorders, particularly those considered to be treatment-resistant.     

Reproductive effects of a pegylated curcumin

Curcumin, a polyphenol derived from the rhizome turmeric, has potential as an anticancer agent. We synthesized an amphipathic/surfactant pegylated curcumin (curcumin-PEG) designed for parenteral administration. Objectives of these investigations were to assess side-effects of a therapeutic regimen of curcumin-PEG in a preclinical model. Intraperitoneal (ip) tumor burdens were reduced in athymic female mice grafted with human SKOV-3 ovarian adenocarcinoma cells and injected intravenously (iv) with curcumin-PEG. There were no gross anatomical or histopathological effects detected in non-reproductive organs. Uteri (luminal fluid imbibition) and ovaries (decreased folliculogenesis) were affected by treatment. Curcumin-PEG ip hastened the onset of puberty in immature female mice. Live births were reduced in mature females housed with males and treated iv with curcumin-PEG; mating (vaginal plugs) was not affected. Accessory gland weights, testicular testosterone concentrations, and spermatogenesis were diminished in mature male mice following iv curcumin-PEG. Estrogenic/antiandrogenic and pregnancy-disrupting effects of a water soluble/bioavailable curcumin were demonstrated.     

Immunomodulatory effects of curcumin: in-vivo

Curcumin specifically exhibits cytostatic and cytotoxic effects against tumors of multiple origin. Previously we have demonstrated apoptotic activity of curcumin against tumor cells with no effect on normal cells in-vitro. Many anti-cancer drugs exhibit deleterious effects on immune cells, which restrict their wide use in-vivo. In the present study, we have evaluated the effect of curcumin on the major functions of T cells, natural killer cells, macrophages and on total splenocytes in-vivo, which insight the role of curcumin on their broad effector functions. This study demonstrates that prolonged curcumin-injections (i.p.) do not impair the cytotoxic function of natural killer cells, the generation of reactive oxygen species and nitric oxide from macrophages and the levels of Th1 regulatory cytokines remained unaltered. Interestingly, curcumin-injections enhanced the mitogen and antigen induced proliferation potential of T cells. We have also evaluated immunomodulatory effects of curcumin in ascites-bearing animals. This study strengthens our belief that curcumin is a safe and useful immunomodulator for the immune system.     

Comparative effects of curcumin and photo-irradiated curcumin on alcohol- and polyunsaturated fatty acid-induced hyperlipidemia.

It is a known fact that ethanol increases lipid levels in humans and experimental animals. Reports show that the increased intake of polyunsaturated fatty acids (PUFAs) along with alcohol produces various pathological changes in liver resulting in hyperlipidemia. Heating of oil rich in PUFA produces various lipid peroxidative end products, which aggravate the pathological changes. In the present study, we have investigated the effect of curcumin (C) and photo-irradiated curcumin (IC) on alcohol- and PUFA-induced hyperlipidemia. Our results showed that the activities of alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT) in plasma and levels of cholesterol, triglycerides (TGs) and free fatty acids (FFAs) in tissues were increased significantly in both alcohol + raw as well as heated PUFA groups compared to normal, but decreased significantly on treatment with curcumin and IC. The IC treatment decreased the levels more significantly compared to curcumin. The phospholipids (PLs) were increased significantly in heart and intestine and decreased in liver and kidney in both alcohol + raw as well as heated PUFA groups. The levels were significantly decreased in liver and kidney and increased in intestine and heart in both curcumin- and IC-treated groups. But the effect of IC was more pronounced than curcumin. Histopathological observations were also in correlation with the biochemical parameters. Thus, photo-irradiated curcumin proves itself to be more effective than curcumin in treating the above pathological conditions.     

姜黄素与Hsp90相互作用以及对Hsp90ATPase 活性的影响

目的 研究姜黄素(curcumin)与Hsp90的结合作用,及其对Hsp90-ATPase 活性抑制作用.方法 采用荧光光谱实验,选取280 nm为激发波长,290~510 nm的波长范围内进行荧光光谱扫描,研究不同浓度curcumin与Hsp90的相互作用.采用孔雀绿磷钼酸铵-无机磷检测法,研究curcumin对Hsp90-ATPase活性抑制.结果 curcumin解离常数为(21.608±1.752) μmol·L-1,格尔德霉素(GA)为(17.372±1.200) μmol·L-1.当ATP为1 mmol·L-1时,GA作用于Hsp90的IC50值为0.38 μmol·L-1,curcumin的IC50值为3.75 μmol·L-1也有较强的Hsp90-ATPase抑制活性.结论 经过荧光光谱分析,可以确定curcumin与Hsp90的结合机制,且curcumin能抑制Hsp90-ATPase活性.     

淫羊藿苷对产前应激子代大鼠抗抑郁作用研究

目的观察淫羊藿苷对产前应激子代抑郁样行为的干预作用,并探究其作用机制。方法本文采用慢性束缚应激对孕后期母鼠建立抑郁模型,将♂SD子代大鼠随机分为5组:空白对照组(CON)、产前应激组(PS)、生理盐水组(NS)、淫羊藿苷高剂量组(80 mg·kg~(-1))、淫羊藿苷低剂量组(40 mg·kg~(-1))。采用强迫游泳实验和旷场实验对各组大鼠的抑郁样行为进行评价,并通过Western blot测定各组大鼠前额叶皮层区m Glu R1、m Glu R5、EAAT2蛋白的表达。结果与CON组相比,PS组子代大鼠挣扎时间和穿越中央格次数减少(P<0.01,P<0.05),表现出明显的抑郁样行为。PS组较CON组前额叶皮层区mGluR1、mGluR5蛋白表达明显升高(P<0.01,P<0.05),而EAAT2蛋白表达明显降低(P<0.05)。与NS组相比,淫羊藿苷高、低剂量组均能明显增加子代大鼠的挣扎时间(P<0.05,P<0.01)和穿越中央格次数(P<0.05)。淫羊藿苷干预后(80、40 mg·kg~(-1))均能明显改善前额叶皮层区mGluR1、mGluR5及EAAT2蛋白的表达。结论淫羊藿苷对产前应激子代大鼠具有明显的抗抑郁作用,其作用机制可能与脑内Ⅰ族mGluRs的调制作用相关。     

Comparative effects of curcumin and an analogue of curcumin in carbon tetrachloride-induced hepatotoxicity in rats

We have evaluated the comparative effect of curcumin (diferuloyl methane) and its analogue [bis-1,7-(2-hydroxyphenyl)-hepta-1,6-diene-3,5-dione] (BDMC-A) on carbon tetrachloride-induced hepatotoxicity in rats. Administration of carbon tetrachloride (3 ml/kg/week) for three months significantly (P<0.05) increased the levels of marker enzymes such as aspartate transaminase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transferase (GGT). The levels of plasma thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides were also significantly (P<0.05) increased. We have observed a significant (P<0.05) decrease in the levels of plasma reduced glutathione (GSH), vitamin C and vitamin E. There was a significant (P<0.05) increase in the levels of TBARS and hydroperoxides in liver and kidney and a significant (P<0.05) decrease in the activities of enzymic antioxidants- superoxide dismutase (SOD), catalase and GSH peroxidase along with GSH in CCl(4)-treated rats. Oral administration of curcumin and BDMC-A to CCl(4)-induced rats for a period of three months significantly (P<0.05) decreased the levels of marker enzymes, plasma TBARS and hydroperoxides and increased the levels of plasma and tissue antioxidants. Histopathological studies of liver also showed protective effect of curcumin and BDMC-A. We have observed thickening of blood vessels and microvesicular fatty changes around the portal triad in CCl(4)-treated rat liver. Treatment with curcumin showed only mild sinusoidal dilatation while with BDMC-A there was only mild portal inflammation. The effect exerted by BDMC-A was found to be more promising than curcumin.     

Immunomodulatory effects of diarylpentanoid analogues of curcumin

Diarylpentanoid analogues of curcumin are known for their various pharmacological activities which include the inhibition of inflammatory mediators and are good candidates as immunomodulators that could be useful in the treatment of inflammation. In the work described here, seventeen diarylpentanoid curcumin analogues were assessed for their inhibitory effects on the reactive oxygen species (ROS) production, chemotaxis and phagocytosis of human neutrophils. ROS production was evaluated using luminol and lucigenin-based chemiluminesence assay, while inhibition of isolated polymorphonuclear neutrophils chemotaxis and phagocytosis abilities were investigated using the Boyden chamber technique and the Phagotest kit, respectively. Two of the analogues, compounds 1e and 2e, which contain the 2-methyl-4(N-ethyl-N-ethylacetonitrile)aniline functional group, were active in all the assays performed. Moreover, analogues containing heteroatoms (1a, 1e, 2c, 2d, 2e, 3a and 3c) were active in suppressing the neutrophil phagocytic activity. The information obtained gave new insight into curcumin analogues with the potential to be developed as new immunomodulators.     

姜黄素衍生物64PH的抗肿瘤作用

目的:探讨姜黄素衍生物64PH的体内外抗肿瘤活性。方法:MTT法检测64PH对小鼠B16黑色素瘤细胞及人HepG2肝癌细胞的体外增殖抑制作用;采用小鼠移植性肿瘤H22观察64PH的体内抑瘤活性,HE染色观察肿瘤血管新生。结果:64PH对B16 的IC₅₀分别为10.30 μg·ml^-1(24 h),3.12 μg·ml^-1(48 h), 2.67 μg·ml^-1(72 h),对HepG2的IC₅₀分别为5.60 μg·ml^-1(24 h),7.60 μg·ml^-1(48 h),5.92 μg·ml^-1(72 h);低剂量(100 mg·kg^-1)、高剂量(300 mg·kg^-1)64PH对小鼠H22的抑瘤率分别为26.1%,33.0%,且可明显抑制小鼠H22肿瘤的血管生成。结论:64PH在体内外均具有较好的抗肿瘤活性。     

A screening of curcumin derivatives for antibacterial phototoxic effects studies on curcumin and curcuminoids. XLIII

Curcumin, bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione, has potential as a photosensitiser for photodynamic treatment of localised superficial infections in e.g., the mouth or skin. The aim of the present study was to evaluate the in vitro antibacterial phototoxic potential of a series of five curcumin derivatives. The gram-positive Enterococcus faecalis and the gram-negative Escherichia coli were used as bacterial models. The bacteria were exposed to curcuminoid preparations in two concentrations (2.5 and 25.0 microM) in combination with a constant irradiation dose (5 J/cm2). The UV-VIS absorption spectrum of the curcuminoids was in the same range as curcumin, 300-500 nm. Compound 1 (dimethoxycurcumin; C1) and compound 3 (bisdemethoxycurcumin; C3) were strongly phototoxic towards E. faecalis (no surviving bacteria) and showed a lower but significant effect towards E. coli (< or = 0.5 log reductions and 1 - 4 log reductions, respectively). Compound 2 (C2) and compound 4 (C4) in combination with blue light reduced the colony forming ability of E. faecalis (approximately 1-4 log reductions). The phototoxic effect of the curcuminoids varied with concentration, and for compounds C1, C2 and C3 it was further influenced by the addition of polyethylene glycol 400 (PEG 400) to the preparations. 2,6-Divanillylidenecyclohexanone (C5) showed very low phototoxic potential (< 0.2 log reductions) under the conditions used in the present study. The addition of polyethylene glycol 400 (PEG 400) seemed to increase the solubility of compound C1, C3 and C5 in phosphate buffered saline (PBS). This investigation demonstrates the importance and influence of the substituents on the phenolic rings and the keto-enol moiety for the phototoxic potential of curcumin and its derivatives.     

Curcumin-cyclodextrin complexes enhanced the anti-cancer effects of curcumin

Curcumin (CUR), as a yellow pigment in the spice turmeric (Curcuma longa), possessed a pleiotropic application containing cancer therapy. Due to its poor oral bioavailability, the objective of this study was to investigate the use of curcumin-cyclodextrin complexes (CD15) as an approach to cancer chemoprevention. In this study, CUR encapsulation into the β-cyclodextrin (CD) cavity was achieved by the saturated aqueous solution method. CD15 was characterized by Fourier transform infrared (FTIR) and UV spectra analyses. An optimized CD15 was evaluated by cellular uptake and anti-cancer activity. As a result, CD15 enhanced curcumin delivery and improved its therapeutic efficacy compared with free curcumin in vivo and in vitro. Therefore, through regulation of MAPK/NF-κB pathway, CD15 up-regulated p53/p21 pathway, down-regulated CyclinE-CDK2 combination and increased Bax/caspase 3 expression to induce cellar apoptosis and G1-phase arrest. In conclusion, these results suggested that CD15 formulation should be used as a system for improving curcumin delivery and its therapeutic efficacy in lung cancer.     

Cytotoxic effects of curcumin on osteosarcoma cell lines

Curcumin (diferuloylmethane), one of the main components of the Indian spice turmeric, is known to possess potent anti-inflammatory and anti-oxidant properties. In addition, curcumin has also been shown to have in vitro and in vivo efficacy against a variety of malignancies. In the current study we examined the cytotoxic effect of curcumin on seven osteosarcoma (OS) cell lines with varying degrees of in vivo metastatic potential. Curcumin inhibited the growth of all OS cell lines tested with half-maximal inhibitory concentration values ranging from 14.4 to 24.6 microM. Growth inhibition was associated with a dose dependent increase in the number of apoptotic cells and accumulation of cells in the G(2)/M phase of the cell cycle. Curcumin treatment also resulted in cleavage of caspase-3 and poly adenosine diphosphate-ribose polymerase. Moreover, curcumin treatment was associated with an increase in cellular levels of the apoptotic B-cell leukemia/lymphoma 2 (Bcl-2)-associated X protein and a decrease in cellular content of the anti-apoptotic protein Bcl-2. In addition, curcumin treatment also inhibited the migration of OS cell lines. These data indicate that the potent cytotoxic activity of curcumin on OS cell lines is mediated by induction of apoptotic processes. Thus, curcumin has potential to be a novel OS chemotherapeutic agent.     

Antidepressant effects of nicotine in an animal model of depression

Epidemiological studies indicate a high incidence of cigarette smoking among depressed individuals. Moreover, individuals with a history of depression have a much harder time giving up smoking. It has been postulated that smoking may reflect an attempt at self-medication with nicotine by these individuals. Although some animal and human studies suggest that nicotine may act as an antidepressant, further verification of this hypothesis and involvement of nicotinic cholinergic system in depressive symptoms is required. Flinders Sensitive Line (FSL) rats have been proposed as an animal model of depression. These rats, selectively bred for their hyperresponsiveness to cholinergic stimulation, show an exaggerated immobility in the forced swim test compared to their control Flinders Resistant Line (FRL) rats. Acute or chronic (14 days) administration of nicotine (0.4 mg/kg SC) significantly improved the performance of the FSL but not the FRL rats in the swim test. The effects of nicotine on swim test were dissociable from its effects on locomotor activity. Moreover, the FSL rats had significantly higher [³H]cytisine binding (selective for the α₄β₂ nicotinic receptor subtype) but not [¹²⁵I]alpha-bungarotoxin binding (selective for the α₇ subtype) in the frontal cortex, striatum, midbrain and colliculi compared to FRL rats. These data strongly implicate the involvement of central nicotinic receptors in the depressive characteristics of the FSL rats, and suggest that nicotinic agonists may have therapeutic benefits in depressive disorders. Received: 9 June 1998/Final version: 6 August 1998     

Antidepressant drugs given repeatedly increase the behavioural effects of methoxamine

In this study we investigated the effect of imipramine, citalopram and mianserin on behavioural effects of methoxamine, an α₁-adrenoceptor agonist, in the rat. Methoxamine (25 and 50 m?g) given into the brain lateral ventricle, increases the exploratory activity assessed in the open field test (time of walking, ambulatory activity, rearing ⁺ peeping). The studied antidepressants, administered repeatedly (10 mg/kg p.o., twice daily, 14 days) but not in single doses, enhance the above effects of methoxamine. The results provide further arguments for the hypothesis that antidepressant drugs administered repeatedly induce a functional α₁-adrenoceptor up-regulation.     

姜黄素的体外抗癌作用及其水溶液的稳定性

目的探讨姜黄素（curcumin，Cur）对人癌细胞株的体外作用特点及其水溶液的稳定性。方法以MTT法观察对人胃癌MGC803、人肝癌Be17402、人红白血病K562及其耐阿霉素株K562／ADM等的体外杀伤作用，并以体外活性变化为指标观察Cur水溶液的稳定性。结果Cur8.5～136.0μmol·L-1对上述细胞的IC50分别为13.0，15.9，11.7，62.6μmol·L-1;低于8.5μmol·L-1就能完全对抗41.5nmol·L-1表皮生长因子（EGF）的促增殖作用。Cur水溶液于4℃贮存3～7d体外抗癌活性明显下降。结论Cur对MGC803、Be17402、K562等有明显的杀伤作用，并能对抗EGF的促增殖作用，其水溶液稳定性较差。