Far-infrared therapy promotes exercise capacity and glucose metabolism in mice by modulating microbiota homeostasis and activating AMPK.

The benefits of physical exercise on human health make it desirable to identify new approaches that would mimic or potentiate the effects of exercise to treat metabolic diseases. However, whether far-infrared (FIR) hyperthermia therapy could be used as exercise mimetic to realize wide-ranging metabolic regulation, and its underling mechanisms remain unclear. Here, a specific far-infrared (FIR) rays generated from graphene-based hyperthermia devices might promote exercise capacity and metabolisms. The material characterization showed that the graphene synthesized by chemical vapour deposition (CVD) was different from carbon fiber, with single-layer structure and high electrothermal transform efficiency. The emission spectra generated by graphene-FIR device would maximize matching those adsorbed by tissues. Graphene-FIR enhanced both core and epidermal temperatures, leading to increased blood flow in the femoral muscle and the abdominal region. The combination of microbiomic and metabolomic analysis revealed that graphene-FIR modulates the metabolism of the gut-muscle axis. This modulation was characterized by an increased abundance of short-chain fatty acids (SCFA)-producing bacteria and AMP, while lactic acid levels decreased. Furthermore, the principal routes involved in glucose metabolism, such as glycolysis and gluconeogenesis, were found to be altered. Graphene-FIR managed to stimulate AMPK activity by activating GPR43, thus enhancing muscle glucose uptake. Furthermore, a microbiota disorder model also demonstrated that the graphene-FIR effectively restore the exercise endurance with enhanced p-AMPK and GLUT4. Our results provided convincing evidence that graphene-based FIR therapy promoted exercise capacity and glucose metabolism via AMPK in gut-muscle axis. These novel findings regarding the therapeutic effects of graphene-FIR suggested its potential utility as a mimetic agent in clinical management of metabolic disorders.

Far-Infrared Therapy Based on Graphene Ameliorates High-Fat Diet-Induced Anxiety-Like Behavior in Obese Mice via Alleviating Intestinal Barrier Damage and Neuroinflammation.

The consumption of a high-fat diet (HFD) has been implicated in the etiology of obesity and various neuropsychiatric disturbances, including anxiety and depression. Compelling evidence suggests that far-infrared ray (FIR) possesses beneficial effects on emotional disorders. However, the efficacy of FIR therapy in addressing HFD-induced anxiety and the underlying mechanisms remain to be elucidated. Here, we postulate that FIR emitted from a graphene-based therapeutic device may mitigate HFD-induced anxiety behaviors. The graphene-FIR modify the gut microbiota in HFD-mice, particularly by an enriched abundance of beneficial bacteria Clostridiaceae and Erysipelotrichaceae, coupled with a diminution of harmful bacteria Lachnospiraceae, Anaerovoracaceae, Holdemania and Marvinbryantia. Graphene-FIR also improved intestinal barrier function, as evidenced by the augmented expression of the tight junction protein occludin and G protein-coupled receptor 43 (GPR43). In serum level, we observed the decreased free fatty acids (FFA), lipopolysaccharides (LPS), diamine oxidase (DAO) and D-lactate, and increased the glucagon-like peptide-2 (GLP-2) levels in graphene-FIR mice. Simultaneously, inflammatory cytokines IL-6, IL-1ß, and TNF-α manifested a decrease subsequent to graphene-FIR treatment in both peripheral and central system. Notably, graphene-FIR inhibited over expression of astrocytes and microglia. We further noticed that the elevated the BDNF and decreased TLR4 and NF-κB expression in graphene-FIR group. Overall, our study reveals that graphene-FIR rescued HFD-induced anxiety via improving the intestine permeability and the integrity of blood-brain barrier, and reduced inflammatory response by down regulating TLR4/NF-κB inflammatory pathway.

Xinyang Tablet attenuates chronic hypoxia-induced right ventricular remodeling via inhibiting cardiomyocytes apoptosis.

BACKGROUND: Hypoxia-induced pulmonary hypertension (HPH) is one of the fatal pathologies developed under hypobaric hypoxia and eventually leads to right ventricular (RV) remodeling and RV failure. Clinically, the mortality rate of RV failure caused by HPH is high and lacks effective drugs. Xinyang Tablet (XYT), a traditional Chinese medicine exhibits significant efficacy in the treatment of congestive heart failure and cardiac dysfunction. However, the effects of XYT on chronic hypoxia-induced RV failure are not clear. METHODS: The content of XYT was analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS). Sprague-Dawley (SD) rats were housed in a hypobaric chamber (equal to the parameter in altitude 5500 m) for 21 days to obtain the RV remodeling model. Electrocardiogram (ECG) and hemodynamic parameters were measured by iWorx Acquisition & Analysis System. Pathological morphological changes in the RV and pulmonary vessels were observed by H&E staining and Masson's trichrome staining. Myocardial apoptosis was tested by TUNEL assay. Protein expression levels of TNF-α, IL-6, Bax, Bcl-2, and caspase-3 in the RV and H9c2 cells were detected by western blot. Meanwhile, H9c2 cells were induced by CoCl2 to establish a hypoxia injury model to verify the protective effect and mechanisms of XYT. A CCK-8 assay was performed to determine the viability of H9c2 cells. CoCl2-induced apoptosis was detected by Annexin-FITC/PI flow cytometry and Hoechst 33,258 staining. RESULTS: XYT remarkably improved RV hemodynamic disorder and ECG parameters. XYT attenuated hypoxia-induced pathological injury in RV and pulmonary vessels. We also observed that XYT treatment decreased the expression levels of TNF-α, IL-6, Bax/Bcl-2 ratio, and the numbers of myocardial apoptosis in RV. In H9c2 myocardial hypoxia model, XYT protected H9c2 cells against Cobalt chloride (CoCl2)-induced apoptosis. We also found that XYT could antagonize CoCl2-induced apoptosis through upregulating Bcl-2, inhibiting Bax and caspase-3 expression. CONCLUSIONS: We concluded that XYT improved hypoxia-induced RV remodeling and protected against cardiac injury by inhibiting apoptosis pathway in vivo and vitro models, which may be a promising therapeutic strategy for clinical management of hypoxia-induced cardiac injury.

Melatonin pretreatment prevents propofol-induced sleep disturbance by modulating circadian rhythm in rats.

Postoperative sleep disorder frequently occurs in patients after surgery. Sleep disturbance aggravates pain, anxiety, and delirium, which is an important risk factor for poor recovery. Circadian rhythm disorder induced by general anesthesia plays important role in postoperative sleep disorders. A large number of clinical studies have shown that various forms and duration of general anesthesia can lead to postoperative sleep disorders. In this study, the effect of prolonged propofol anesthesia on biological rhythm was comprehensively evaluated by wireless physiological telemetry system, and the therapeutic effect of exogenous melatonin pretreatment was further investigated. The results showed that prolonged propofol anesthesia had significant impacts on the circadian rhythm of sleep, body temperature, locomotor activity and endogenous melatonin secretion within 24 h following anesthesia, resulting in diminished oscillation amplitude. In hypothalamus, the expression of circadian factor PER and CRY were inhibited by propofol, possibly through activation of CAMK-CREB signaling pathway. Post-translational factors GSK-3ß, SIRT1, AMPK were also involved in the regulation of circadian factors after propofol anesthesia. Melatonin pretreatment could restore circadian rhythm process by regulating circadian factor expression through post-translational modulation and prohibit the over-synthesis of melatonin in pineal gland. This study verified the effects of anesthetics on circadian rhythm and further evaluated the potential therapeutic effect of melatonin on postoperative circadian rhythm and sleep disorders.

Design, synthesis, and activity evaluation of novel erythropoietin mimetic peptides.

The approval of the erythropoietin (EPO) mimetic peptide drug peginesatide in 2012 was a breakthrough for the treatment of secondary anemia. However, due to severe allergic reactions, peginesatide was recalled a year later. In this study, 12 novel peptides were designed and synthesized by substituting specific amino acids of the monomeric peptide in peginesatide, with the aim of obtaining new EPO mimetic peptides with higher activities and lower side effects than the parent compound. Their cell proliferation activities were evaluated, and the structure-activity relationships were analyzed. Five compounds had equal cell proliferation activity to the control peptide. Among them, one compound showed a higher in vivo activity than the control peptide, with no obvious side effects.

A pH responsive complexation-based drug delivery system for oxaliplatin.

A responsive drug delivery system (DDS) for oxaliplatin (OX) has been designed with a view to overcoming several drawbacks associated with this anticancer agent, including fast degradation/deactivation in the blood stream, lack of tumor selectivity, and low bioavailability. The present approach is based on the direct host-guest encapsulation of OX by a pH-responsive receptor, carboxylatopillar[6]arene (CP6A). The binding affinities of CP6A for OX were found to be pH-sensitive at biologically relevant pH. For example, the association constant (Ka) at pH 7.4 [Ka = (1.02 ± 0.05) × 104 M-1] is 24 times larger than that at pH 5.4 [Ka = (4.21 ± 0.06) × 102 M-1]. Encapsulation of OX within the CP6A cavity did not affect its in vitro cytotoxicity as inferred from comparison studies carried out in several cancer cells (e.g., the HepG-2, MCF-7, and A549 cell lines). On the other hand, complexation by CP6A serves to increase the inherent stability of OX in plasma by 2.8-fold over a 24 h incubation period. The formation of a CP6A⊃OX host-guest complex served to enhance in a statistically significant way the ability of OX to inhibit the regrowth of sarcoma 180 (S180) tumors in Kunming (KM) mice xenografts. The improved anticancer activity observed in vivo for CP6A⊃OX is attributed to the combined effects of enhanced stability of the host-guest complex and the pH-responsive release of OX. Specifically, it is proposed that OX is protected as the result of complex formation and then released effectively in the acidic tumor environment.

Design, synthesis, and evaluation of water-soluble morpholino-decorated paclitaxel prodrugs with remarkably decreased toxicity.

Novel water-soluble paclitaxel prodrugs were designed and synthesized by introducing morpholino groups through different linkers. These derivatives showed 400-20,000-times greater water solubility than paclitaxel as well as comparable activity in MCF-7 and HeLa cell lines. The prodrug PM4 was tested in the S-180 tumor mouse model, with paclitaxel as the positive control. The results showed that PM4 had comparable antitumor activity as paclitaxel, with tumor inhibition of 54% versus 56%, and remarkably decreased toxicity. The survival rate of treated mice was 8/8 in the PM4 group, compared to 3/8 in the paclitaxel group.

Tea polyphenols promote cardiac function and energy metabolism in ex vivo rat heart with ischemic/reperfusion injury and inhibit calcium inward current in cultured rat cardiac myocytes.

OBJECTIVE: To investigate the protective effects of tea polyphenols (TP) against myocardial ischemia/reperfusion (IR) injuries and explore the possible mechanisms. METHODS: Langendorff-perfused rat hearts were subjected to ischemia for 30 min followed by reperfusion for another 30 min. Myocardial function indices were measured by a left ventricular cannula via a pressure transducer connected to the polygraph in isolated Langendorff hearts and energy metabolism was measured using (31)P nuclear magnetic resonance (NMR) spectroscopy. Whole-cell atch-clamp technique was used to record calcium inward current (I(Ca-L)) in cultured rat cardiac myocytes. RESULTS: Compared with the control hearts, the ex vivo rat hearts with 2.5 mg/L TP treatment showed significantly increased left ventricular developed pressure (LVDP), maximal rise rate of LVDP (+dp/d(tmax)), maximal fall rate of LVDP (-dp/dt(max)), and coronary flow (CF) (P<0.05). During both cardiac ischemia and reperfusion phase, ATP and PCr levels were elevated significantly in TP-treated hearts compared with those in the control hearts (P<0.05). In cultured rat cardiac myocytes, ICa-L was remarkably decreased by TP at the doses of 2.5 and 5.0 mg/L (P<0.01). CONCLUSION: Our results support a possible protective role of TP against myocardial IR injury by improving myocardial energy metabolism and inhibiting I(Ca-L) in the cardiac myocytes.

A cross-linking strategy provides a new generation of biodegradable and biocompatible cyanoacrylate medical adhesives.

Addition polymerization usually results in polymers with long carbon-carbon main chains. Cyanoacrylate (CA) is arguably an important example of such polymerization and has gained widespread acceptance as an all-purpose adhesive. However, CA-based medical adhesives have never been approved by the U.S. Federal Drug Administration for use below the skin, mainly due to the low biodegradability and biocompatibility of their solid glue after polymerization. In this research, a cross-linking strategy involving the combination of alkyl-CA and the cross-linking agent poly(ethylene glycol)-di(cyanoacrylate) (CA-PEG-CA) to form a copolymeric network was used to synthesize a new generation of biodegradable CA medical adhesives. The degradability could be modulated by adjusting the ratio of CA-PEG-CA to alkyl-CA and the length of PEG. An optimal composite adhesive, LKJ11, was shown to have excellent biodegradability, adhesive capability, and biocompatibility. Importantly, the molecular weight of polycyanoacrylate chains in the polymerized LKJ11 was greatly reduced compared to those polymerized from pure butyl-CA. Thus, the degradation product could be readily extracted. The results showed that LKJ11 represents a new generation of CA-based biodegradable medical adhesives. This advance also provides a general strategy to facilitate the conversion of other polymers with long carbon-carbon main chains to a biodegradable form, thereby expanding the novel applications available for traditional polymeric materials.

The synthesis and antitumor activity of twelve galloyl glucosides.

Twelve galloyl glucosides 1-12, showing diverse substitution patterns with two or three galloyl groups, were synthesized using commercially available, low-cost D-glucose and gallic acid as starting materials. Among them, three compounds, methyl 3,6-di-O-galloyl-α-D-glucopyranoside (9), ethyl 2,3-di-O-galloyl-α-D-glucopyranoside (11) and ethyl 2,3-di-O-galloyl-ß-D-glucopyranoside (12), are new compounds and other six, 1,6-di-O-galloyl-ß-D-glucopyranose (1), 1,4,6-tri-O-galloyl-ß-D-glucopyranose (2), 1,2-di-O-galloyl-ß-D-glucopyranose (3), 1,3-di-O-galloyl-ß-D-glucopyranose (4), 1,2,3-tri-O-galloyl-α-D-glucopyranose (6) and methyl 3,4,6-tri-O-galloyl-α-D-glucopyranoside (10), were synthesized for the first time in the present study. In in vitro MTT assay, 1-12 inhibited human cancer K562, HL-60 and HeLa cells with inhibition rates ranging from 64.2% to 92.9% at 100 µg/mL, and their IC50 values were determined to be varied in 17.2-124.7 µM on the tested three human cancer cell lines. In addition, compounds 1-12 inhibited murine sarcoma S180 cells with inhibition rates ranging from 38.7% to 52.8% at 100 µg/mL in the in vitro MTT assay, and in vivo antitumor activity of 1 and 2 was also detected in murine sarcoma S180 tumor-bearing Kunming mice using taxol as positive control.

Inhibition of vesicular glutamate transporters contributes to attenuate methamphetamine-induced conditioned place preference in rats.

Accumulating evidence suggests that glutamatergic system plays a crucial role in methamphetamine (METH) addiction. In the glutamatergic transmission, vesicular glutamate transporters (VGLUTs) are responsible for transporting glutamate into synaptic vesicles and affect the glutamate concentrations in the synaptic cleft. It is well documented that VGLUTs play an essential role in pathophysiology of several psychiatric and neurological diseases, however, whether VGLUTs also have a role in addiction caused by psychostimulant drugs is still unknown. The present study was underwent to investigate the effect of inhibition of VGLUTs on METH-induced induce conditioned place preference in rats. Rats were induced to conditioned place preference with METH (0.5, 1.0 and 2.0mg/kg) by intraperitoneal injection. Intracerebroventricular administration of 1.0 or 5.0µg Chicago sky blue 6B (CSB6B), a VGLUTs inhibitor, and 2.5h prior to METH was to observe its effect on METH-induced conditioned place preference in rats. The rats receiving METH showed stronger place preference at the dose of 1.0mg/kg than that of other doses. The intracerebroventricular administration of CSB6B (1.0, 5.0µg) 2.5h prior to the exposure to METH attenuated the acquisition of METH-induced conditioned place preference, while CSB6B itself had no effect on place preference. These results indicate that VGLUTs are involved in the effect of METH-induced conditioned place preference and may be a new target against METH addiction.

Effect of thienorphine on intestinal transit and isolated guinea-pig ileum contraction.

AIM: To evaluate the effect of thienorphine on small intestinal transit in vivo and on guinea-pig ileum (GPI) contraction in vitro. METHODS: The effects of thienorphine on intestinal transit were examined in mice and in isolated GPI. Buprenorphine and morphine served as controls. The distance traveled by the head of the charchol and the total length of the intestine were measured in vivo. Gastrointestinal transit was expressed as a percentage of the distance traveled by the head of the marker relative to the total length of the small intestine. The isolated GPI preparations were connected to an isotonic force transducer and equilibrated for at least 1 h before exposure to drugs. Acetylcholine was used for muscle stimulation. RESULTS: Thienorphine (0.005-1.0 mg/kg, ig) or buprenorphine (0.005-1.0 mg/kg, sc) dose-dependently significantly inhibited gut transit compared with saline. Thienorphine inhibited gut transit less than buprenorphine. The maximum inhibition by thienorphine on the intestinal transit was 50%-60%, whereas the maximum inhibition by morphine on gut transit was about 100%. Thienorphine also exhibited less inhibition on acetylcholine-induced contraction of GPI, with a maximum inhibition of 65%, compared with 93% inhibition by buprenorphine and 100% inhibition by morphine. Thienorphine induced a concentration-dependent decrease in the basal tonus of spontaneous movement of the GPI, the effect of which was weaker than that with buprenorphine. The duration of the effect of thienorphine on the GPI was longer than that with buprenorphine. CONCLUSION: Thienorphine had less influence, but a longer duration of action on GPI contraction and moderately inhibited intestinal transit.

Effect of thienorphine on the isolated uterine strips from pregnant rats.

Opioid dependence is a serious worldwide health problem. Buprenorphine was used as an alternative to methadone for the treatment of opioid dependence, especially for pregnant women. Thienorphine was a partial opioid agonist with long-lasting antinociceptive effect and high oral bioavailability compared with its analogue buprenorphine. Till now, there was still no research about the effect of thienorphine on the isolated uterine muscles. This study examined the effects of thienorphine on the isolated rat oestrus and pregnant uterine strips. Area under the curve (AUC), amplitude and frequency were studied. Thienorphine induced a concentration-dependent decrease in the frequency and amplitude of the contraction on the isolated oestrus and pregnant uterine strips. Thienorphine exhibited less inhibition on the contractile amplitude of the isolated uterine strips from pregnant rats with the IC50 of 54.11 ± 7.41 µΜ, compared with buprenorphine (IC50, 19.42 ± 2.34 µΜ). In addition, thienorphine also exhibited less inhibition on the contractile frequency of the isolated uterine strips from pregnant rats, with the IC50 of 70.68 ± 12.44 µΜ, compared with buprenorphine (IC50, 19.20 ± 3.87 µΜ). On the isolated uterine muscle from pregnant rats, the AUC was decreased by thienorphine but was less potent than buprenorphine, the IC50 was 37.31 ± 7.43 µΜ for thienorphine and 13.52 ± 2.03 µΜ for buprenorphine. Thienorphine exhibited longer duration on the isolated rat pregnant uterine strips than buprenorphine. Thienorphine has less influence and longer duration on the isolated rat uterine muscles during pregnancy, which may be a new useful candidate for the opioid dependent pregnant women.

Chicago sky blue 6B, a vesicular glutamate transporters inhibitor, attenuates methamphetamine-induced hyperactivity and behavioral sensitization in mice.

Several lines of evidence demonstrate that glutamatergic system plays an important role in drug addiction. The present study was designed to investigate the effects of Chicago sky blue 6B (CSB6B), a vesicular glutamate transporters (VGLUTs) inhibitor, on methamphetamine (METH)-induced behaviors in mice. Mice were induced behavioral sensitization to METH by subcutaneous injection of 1mg/kg METH once daily for 7 days and then challenged with 1mg/kg METH in 14th day. Intracerebroventricular administration of CSB6B (7.5µg) 2.5h prior to METH was to observe its effects on METH -induced behavioral sensitization. Our results showed that the expressions of behavioral sensitization were significantly attenuated by intracerebroventricular administration of CSB6B 2.5h prior to METH either during the development period or before methamphetamine challenge in mice, while CSB6B itself had no effect on locomotor activity. Meanwhile, pretreatment of CSB6B also attenuated hyperactivity caused by a single injection of METH in mice. These results demonstrated that CSB6B, a VGLUTs inhibitor, attenuated acute METH-induced hyperactivity and chronic METH-induced behavioral sensitization, which indicated that VGLUTs were involved in the effect of chronic METH-induced behavioral sensitization and may be a new target against the addiction of METH.

Synthesis and antitumor evaluation of novel benzo[d]pyrrolo[2,1-b]thiazole derivatives.

A series of novel 2,3-bis(hydroxymethyl)benzo[d]pyrrolo[2,1-b]thiazoles and their bis(alkylcarbamate) derivatives were synthesized starting from benzothiazole via reaction with dimethyl acetylenedicarboxylate (DMAD)/tetra-fluoro boric acid, catalytic hydrogenation, and alkylcarbamoylation. The anti-proliferative activity of these agents against human leukemia and various solid tumor cell growth in vitro was studied. The structure-activity relationship studies revealed that the bis(alkylcarbamates) derivatives are generally more cytotoxic than the corresponding bis(hydroxymethyl) congeners in inhibiting human lymphoblastic leukemia CCRF-CEM and various human solid tumor cell growth in culture. These agents have no cross-resistance to taxol or vinblastine. Studies on the therapeutic effect against human breast carcinoma MX-1 xenograft showed that complete tumor remission (CR) were achieved by treating with C1-4'-F- or C1-4'-Cl-Ph-bis(i-propylcarbamates) derivatives (19b and 19c, respectively) and more than 99% tumor suppression by the corresponding bis(ethylcarbamates) 18b and 18c at the maximal tolerated dose. Alkaline agarose gel shifting assay revealed that the newly synthesized compounds are able to induce DNA interstrand cross-linking. The present studies generated a series of new potent DNA interstrand cross-linking agents, which have potential for further antitumor drug development.

Multifaceted cytoprotection by synthetic polyacetylenes inspired by the ginseng-derived natural product, panaxytriol.

We describe herein the discovery of a series of panaxytriol (PXT)-derived polyacetylene small molecules with promising cytoprotective activity. In mouse xenograft models, we have demonstrated the capacity of our synthetic analogs to mitigate a range of cancer therapeutic agent-induced toxicities, including body weight loss, lethality, neurotoxicity, and hematotoxicity. Our PXT analogs have also been found to reduce radiation-induced body weight loss and lethality in mouse models. Moreover, several PXT analogs appear to exhibit moderate in vivo antiinflammatory activity as well as in vitro immunoenhancing capabilities. These compounds appear to derive their activity through induction of cancer preventive phase 2 enzymes. The studies described herein suggest that coadministration of a PXT-derived agent with cancer chemotherapeutics or radiation therapy may serve to mitigate a range of therapy-associated toxicities.

Novel 2-substituted quinolin-4-yl-benzenesulfonate derivatives: synthesis, antiproliferative activity, and inhibition of cellular tubulin polymerization.

A series of 2-substituted quinolin-4-yl-benzenesulfonate derivatives were synthesized for the purpose of evaluating antiproliferative activity. Structure-activity relationships of the newly synthesized compounds against human lymphoblastic leukemia and various solid tumor cell growths in culture are discussed. Of these derivatives, 2-phenyl-6-pyrrolidinyl-4-quinoline sulfonate analogues 10 f, 10 g, and 10 k, and 4'-nitrophenyl sulfonate 10 m exhibit superior cytotoxicity over other sulfonates. The antiproliferative activities of these compounds correlate well with their abilities to induce mitotic arrest and apoptosis. Mechanistic studies indicate that they target the vinblastine binding site of tubulin and inhibit cellular tubulin polymerization. Hence, these compounds induce the formation of aberrant mitotic spindles and mitotic arrest, resulting in intensive apoptosis. The tested compounds were shown to be poor substrates for membrane multidrug resistance transporters. The present studies suggest that these newly synthesized compounds are promising tubulin polymerization inhibitors and are worthy of further investigation as antitumor agents.

TH-030418: a potent long-acting opioid analgesic with low dependence liability.

Numerous efforts have been made on the chemical modification of opioid compounds, with the ultimate goal of developing new opioid analgesics that is highly potent and low/non-addictive. In a search for such compounds, TH-030418 [7α-[(R)-1-hydroxy-1-methyl-3-(thien-3-yl)-propyl]-6,14-endo-ethanotetrahydrooripavine] was synthesized. Here, we evaluated the pharmacological activities of TH-030418, in comparison with morphine, the prototype opioid analgesic. In radioligand binding assays, TH-030418 bound potently and nonselectively to µ-, δ-, κ-, and ORL1 (opioid receptor-like 1) receptors stably expressed in CHO (Chinese hamster ovary) cells with K (i) values of 0.56, 0.73, 0.60, and 1.55 nM, respectively. When administered subcutaneously, TH-030418 was much more potent than morphine in analgesia, with the ED(50) values of 1.37 µg/kg and 1.70 µg/kg in hot plate and acetic acid writhing tests, respectively. The opioid antagonist naloxone blocked the antinociceptive effect of TH-030418, indicating that the action of TH-030418 was mediated by opioid receptors. The antinociceptive effect of s.c. TH-030418 in hot plate test lasted for more than 12 h, which is much longer than those of morphine (2.5 h) and dihydroetorphine (1.5 h). In addition, naloxone did not precipitate withdrawal syndrome in the mice treated with TH-030418 previously. Most importantly, TH-030418 did not induce conditioned place preference in mice after chronic treatment. These results indicate that TH-030418 is a potent long-acting opioid analgesic with low dependence liability and may be of some value in the development of new analgesics.

Design, synthesis and antitumor evaluation of phenyl N-mustard-quinazoline conjugates.

A series of N-mustard-quinazoline conjugates was synthesized and subjected to antitumor studies. The N-mustard pharmacophore was attached at the C-6 of the 4-anilinoquinazolines via a urea linker. To study the structure-activity relationships of these conjugates, various substituents were introduced to the C-4 anilino moiety. The preliminary antitumor studies revealed that these agents exhibited significant antitumor activity in inhibiting various human tumor cell growths in vitro. Compounds 21b, 21g, and 21h were selected for further antitumor activity evaluation against human breast carcinoma MX-1 and prostate PC-3 xenograft in animal model. These agents showed 54-75% tumor suppression with low toxicity (5-7% body-weight changes). We also demonstrate that the newly synthesized compounds are able to induce DNA cross-linking through alkaline agarose gel shift assay and inhibited cell cycle arrest at G2/M phase.

Design, synthesis, and biological evaluation of novel water-soluble N-mustards as potential anticancer agents.

A series of novel water-soluble N-mustard-benzene conjugates bearing a urea linker were synthesized. The benzene moiety contains various hydrophilic side chains are linked to the meta- or para-position of the urea linker via a carboxamide or an ether linkage. The preliminary antitumor studies revealed that these agents exhibited potent cytotoxicity in vitro and therapeutic efficacy against human tumor xenografts in vivo. Remarkably, complete tumor remission in nude mice bearing human breast carcinoma MX-1 xenograft and significant suppression against prostate adenocarcinoma PC3 xenograft were achieved by treating with compound 9aa' at the maximum tolerable dose with relatively low toxicity. We also demonstrate that the newly synthesized compounds are able to induce DNA cross-linking through alkaline agarose gel shift assay. A pharmacokinetic profile of the representative 9aa' in rats was also investigated. The current studies suggest that this agent is a promising candidate for preclinical studies.