Optimizing the Extraction and Enrichment of Luteolin from Patrinia villosa and Its Anti-Pseudorabies Virus Activity.

Luteolin from Patrinia villosa exhibits strong antiviral activity. Here, the conditions for extracting and enriching luteolin from P. villosa were optimized. Response surface methodology was used to determine the optimal extraction parameters in terms of reflux time, solvent ratio, extraction temperature, material-to-liquid ratio, and number of extractions. Thereafter, a macroporous resin method was used to enrich luteolin from P. villosa. Finally, the following optimal extraction and enrichment conditions were established: an extraction time of 43.00 min, a methanol/hydrochloric acid solvent ratio of 13:1, an extraction temperature of 77.60 °C, a material/liquid ratio of 1:22, and a total of two extractions. NKA-9 was determined to be the most appropriate resin for enrichment. The ideal adsorption conditions were as follows: a pH of 5.0, a temperature of 25 °C, an initial luteolin concentration of 19.58 µg/mL, a sample loading volume of 2.9 BV, and a sample loading rate of 2 BV/h. The ideal desorption conditions were as follows: distilled water, 30% ethanol and 80% ethanol elution, and 5 BV at a flow rate of 2 BV/h. After optimization, the enrichment recovery rate was 80.06% and the luteolin content increased 3.8-fold. Additionally, the enriched product exhibited a significant inhibitory effect on PRV (Porcine pseudorabies virus) in vitro and in vivo, providing data for developing and applying luteolin from P. villosa.

Modified citrus pectin inhibits breast cancer development in mice by targeting tumor-associated macrophage survival and polarization in hypoxic microenvironment.

Large amounts of tumor-associated macrophages (TAM), which are predominately localized in hypoxia area of the tumor tissue, are associated with the malignant progression of the tumor. In the present study, we investigated the inhibitory effects of modified citrus pectin (MCP), a natural dietary polysaccharide, on the survival and polarization of TAM in relation to its inhibition on the growth and migration of breast cancer. M2 macrophages polarized from human monocyte THP-1 were chosen as a model for TAM. We showed that MCP (0.06%-1%) concentration-dependently suppressed the survival of TAM through inhibiting glucose uptake with a greater extent in hypoxia than in normoxia. Furthermore, MCP treatment decreased ROS level in TAM through its reducibility and inhibiting galectin-3 expression, leading to inhibition of glucose transporter-1 expression and glucose uptake. In addition, MCP suppressed M2-like polarization via inhibiting STAT3 phosphorylation. Moreover, the tumor-promoting effect of TAM could be restrained by MCP treatment as shown in human breast cancer MDA-MB-231 cells in vitro and in mouse breast cancer 4T1-luc orthotopic and metastasis models. In both tumor tissue and lung tissue of the mouse tumor models, the number of TAM was significantly decreased after MCP treatment. Taken together, MCP may be a promising agent for targeting TAM in tumor hypoxic microenvironment for breast cancer treatment.

Brd4 participates in epigenetic regulation of the extinction of remote auditory fear memory.

BACKGROUND: Inaccurate fear memories can be maladaptive and potentially portrait a core symptomatic dimension of fear adaptive disorders such as post-traumatic stress disorder (PTSD), which is generally characterized by an intense and enduring memory for the traumatic events. Evidence exists in support of epigenetic regulation of fear behavior. Brd4, a member of the bromodomain and extra-terminal domain (BET) protein family, serves as a chromatin "reader" by binding to histones in acetylated lysine residues, and hence promotes transcriptional activities. However, less is known whether Brd4 participates in modulating cognitive activities especially memory formation and extinction. Here we provide evidence for a role of Brd4 in modulation of auditory fear memory. Auditory fear conditioning resulted in a biphasic Brd4 activation in the anterior cingulate cortex (ACC) and hippocampus of adult mice. Thus, Brd4 phosphorylation occurred 6 h and 3-14 days, respectively, after auditory fear conditioning. Systemic inhibition of Brd4 with a BET inhibitor, JQ1, impaired the extinction of remote (i.e., 14 days after conditioning) fear memory. Further, conditional Brd4 knockout in excitatory neurons of the forebrain impaired remote fear extinction as observed in the JQ1-treated mice. Herein, we identified that Brd4 is essential for extinction of remote fear in rodents. These results thus indicate that Brd4 potentially plays a role in the pathogenesis of PTSD.

Berberine improves intralipid-induced insulin resistance in murine.

Insulin resistance (IR) is a major metabolic risk factor even before the onset of hyperglycemia. Recently, berberine (BBR) is found to improve hyperglycemia and IR. In this study, we investigated whether BBR could improve IR independent of hyperglycemia. Acute insulin-resistant state was induced in rats by systemic infusion of intralipid (6.6%). BBR was administered via different delivery routes before or after the beginning of a 2-h euglycemic-hyperinsulinemic clamp. At the end of experiment, rats were sacrificed, gastrocnemius muscle was collected for detecting mitochondrial swelling, phosphorylation of Akt and AMPK, as well as the mitochondrial permeability regulator cyclophilin D (CypD) protein expression. We showed that BBR administration markedly ameliorated intralipid-induced IR without affecting blood glucose, which was accompanied by alleviated mitochondrial swelling in skeletal muscle. We used human skeletal muscle cells (HSMCs), AML12 hepatocytes, human umbilical vein endothelial cells, and CypD knockout mice to investigate metabolic and molecular alternations. In either HSMCs or AML12 hepatocytes, BBR (5 µM) abolished palmitate acid (PA)-induced increase of CypD protein levels. In CypD-deficient mice, intralipid-induced IR was greatly attenuated and the beneficial effect of BBR was diminished. Furthermore, we demonstrated that the inhibitory effect of BBR on intralipid-induced IR was mainly mediated by skeletal muscle, but not by intestine, liver, or microvasculature; BBR administration suppressed intralipid-induced upregulation of CypD expression in skeletal muscle. These results suggest that BBR alleviates intralipid-induced IR, which is related to the inhibition of CypD protein expression in skeletal muscle.

Galectin-3 expression and secretion by tumor-associated macrophages in hypoxia promotes breast cancer progression.

Tumor-associated macrophages (TAMs) have been shown to be associated with poor prognosis of cancer and are predominately localized in the hypoxia regions of tumor. We demonstrated in this study that hypoxia increases the synthesis and secretion of galectin-3 by TAMs. The increased expression of galectin-3 in TAMs was seen to be associated with nucleation of transcription factor NF-κB through generation and activation of ROS and promoted tumor growth and metastasis in vitro and in mice through multiple molecular mechanisms. It was found that the TAMs-mediated promotion of tumor growth and metastasis in hypoxia was inhibited by administration of macrophage-depletion agent clodronate liposomal (CL) or galectin-3 inhibitor modified citric pectin (MCP) in orthotopic syngeneic mammary adenocarcinoma model and metastasis model. Co-administration of anti-angiogenesis agent sorafenib or bevacizumab with CL and MCP showed to cause stronger inhibition of tumor growth and metastasis than administration of each agent alone. These results indicate that hypoxia-induced galectin-3 expression and secretion from TAMs promotes tumor growth and metastasis. Targeting the actions of galectin-3 in hypoxia may be a potential therapeutic strategy for cancer treatment.

[Intervention of auricular point sticking on perioperative psychological stress in patients with anorectal diseases].

OBJECTIVE: To explore and quantify the intervention effect of auricular point sticking on perioperative psychological stress in patients with anorectal diseases. METHODS: Eighty patients who underwent anorectal surgery were randomly divided into an observation group (40 cases) and a control group (40 cases). The routine preoperative guidance, preoperative visits, and informed of the postoperative condition were received in the control group. On the basis of the treatment in the control group, auricular point sticking was immediately applied at Shenmen (TF4), Shen (CO10), Wei (CO4), Gan (CO12), Pi (CO13), Pizhixia (AT4), E (AT1), Nie (AT2) and Zhen (AT3) in the observation group.The patients were pressed by themselves, 3 to 5 min per point each time, 5 times a day, and the contralateral auricular points were replaced every 2 or 3 days until 1 week after surgery. The Hamilton anxiety scale (HAMA), Hamilton depression scale (HAMD), and Pittsburgh sleep quality index (PSQI) scores were compared between the two groups before and 7 days after surgery. RESULTS: There was no significant difference in the total HAMA scores between after and before surgery in the observation group (P>0.05). The total HAMA score in the control group was higher than that before surgery (P<0.05). The total HAMA score in the observation group after surgery was lower than that in the control group (P<0.05). There was no significant difference in the total HAMD scores between the two groups before and after surgery (P<0.05). There was no significant difference in the total HAMD scores between the two groups after the surgery (P>0.05). The scores of somatic anxiety factor in the two groups were higher than those before surgery (P<0.05). The scores of somatic anxiety factor in the observation group were lower than those in the control group (P<0.05). The scores of psychotic anxiety factors in the two groups were lower than those before surgery (P<0.05). There was no significant difference in the score of psychotic anxiety factors between the two groups (P>0.05). The total score of PSQI in the two groups was lower than that before surgery (P<0.05), and the total score of PSQI in the observation group was lower than that in the control group (P<0.05). CONCLUSION: Auricular point sticking can effectively improve some psychological stress problems during perioperative period in patients with anorectal diseases.

Glucose Oxidase-Instructed Multimodal Synergistic Cancer Therapy.

Over the past 3 years, glucose oxidase (GOx) has aroused great research interest in the context of cancer treatment due to its inherent biocompatibility and biodegradability, and its unique catalytic properties against ß-d-glucose. GOx can effectively catalyze the oxidation of glucose into gluconic acid and hydrogen peroxide. This process depletes oxygen levels, resulting in elevated acidity, hypoxia, and oxidative stress in the tumor microenvironment. All of these changes can be readily harnessed to develop a multimodal synergistic cancer therapy by combining GOx with other therapeutic approaches. Herein, the representative studies of GOx-instructed multimodal synergistic cancer therapy are introduced, and their synergistic mechanisms are discussed systematically. The current challenges and future prospects to advance the development of GOx-based nanomedicines in this cutting-edge research area are highlighted.

Intervention of auricular point sticking on perioperative psychological stress in patients with anorectal diseases / 中国针灸

OBJECTIVE@#To explore and quantify the intervention effect of auricular point sticking on perioperative psychological stress in patients with anorectal diseases.@*METHODS@#Eighty patients who underwent anorectal surgery were randomly divided into an observation group (40 cases) and a control group (40 cases). The routine preoperative guidance, preoperative visits, and informed of the postoperative condition were received in the control group. On the basis of the treatment in the control group, auricular point sticking was immediately applied at Shenmen (TF), Shen (CO), Wei (CO), Gan (CO), Pi (CO), Pizhixia (AT), E (AT), Nie (AT) and Zhen (AT) in the observation group.The patients were pressed by themselves, 3 to 5 min per point each time, 5 times a day, and the contralateral auricular points were replaced every 2 or 3 days until 1 week after surgery. The Hamilton anxiety scale (HAMA), Hamilton depression scale (HAMD), and Pittsburgh sleep quality index (PSQI) scores were compared between the two groups before and 7 days after surgery.@*RESULTS@#There was no significant difference in the total HAMA scores between after and before surgery in the observation group (>0.05). The total HAMA score in the control group was higher than that before surgery (0.05). The scores of somatic anxiety factor in the two groups were higher than those before surgery (0.05). The total score of PSQI in the two groups was lower than that before surgery (<0.05), and the total score of PSQI in the observation group was lower than that in the control group (<0.05).@*CONCLUSION@#Auricular point sticking can effectively improve some psychological stress problems during perioperative period in patients with anorectal diseases.

Role of early environmental enrichment on the social dominance tube test at adulthood in the rat.

RATIONALE: Environmental enrichment (EE) could influence brain plasticity and behavior in rodents. Whether the early EE may predispose individuals to a particular social hierarchy in the social dominance tube test (SDTT) at adulthood is still unknown. OBJECTIVE: The present study directly investigated the influence of EE on competitive success in the SDTT among adult rats. METHODS: Male rats were maintained in EE from postnatal days 21 to 35. Social dominance behavior was determined by SDTT, competitive food foraging test, and mate preference test at adulthood. IBA-1 expression in the hypothalamus was examined using immunohistochemistry and western blot. RESULTS: EE rats were prone to become submissive during a social encounter with standard environment (SE) rats in the SDTT. No difference was found in food foraging in the competitive food foraging test between SE and EE rats. Male EE rats were more attractive than the SE to the female rats in the mate preference test. IBA-1 expression was found to be decreased in the hypothalamus of EE rats compared to SE group. Infusion of a microglia inhibitor reduced percentage of forward in SE rats in the SDTT. Infusion of DNA methyltransferase inhibitor prevented the development of subordinate status in EE rats and restored the expression of IBA-1 in the hypothalamus. CONCLUSIONS: The results suggest that early EE did not lead to reduced social hierarchy in the male rat. However, EE caused a reduction in the percentage of forward in the SDTT, which might be associated with reduced number of microglia in the hypothalamus.

Activity Based Protein Profiling Leads to Identification of Novel Protein Targets for Nerve Agent VX.

Organophosphorus (OP) nerve agents continue to be a threat at home and abroad during the war against terrorism. Human exposure to nerve agents such as VX results in a cascade of toxic effects relative to the exposure level including ocular miosis, excessive secretions, convulsions, seizures, and death. The primary mechanism behind these overt symptoms is the disruption of cholinergic pathways. While much is known about the primary toxicity mechanisms of nerve agents, there remains a paucity of information regarding impacts on other pathways and systemic effects. These are important for establishing a comprehensive understanding of the toxic mechanisms of OP nerve agents. To identify novel proteins that interact with VX, and that may give insight into these other mechanisms, we used activity-based protein profiling (ABPP) employing a novel VX-probe on lysates from rat heart, liver, kidney, diaphragm, and brain tissue. By making use of a biotin linked VX-probe, proteins covalently bound by the probe were isolated and enriched using streptavidin beads. The proteins were then digested, labeled with isobarically distinct tandem mass tag (TMT) labels, and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Quantitative analysis identified 132 bound proteins, with many proteins found in multiple tissues. As with previously published ABPP OP work, monoacylglycerol lipase associated proteins and fatty acid amide hydrolase (FAAH) were shown to be targets of VX. In addition to these two and other predicted neurotransmitter-related proteins, a number of proteins involved with energy metabolism were identified. Four of these enzymes, mitochondrial isocitrate dehydrogenase 2 (IDH2), isocitrate dehydrogenase 3 (IDH3), malate dehydrogenase (MDH), and succinyl CoA (SCS) ligase, were assayed for VX inhibition. Only IDH2 NADP+ activity was shown to be inhibited directly. This result is consistent with other work reporting animals exposed to OP compounds exhibit reduced IDH activity. Though clearly a secondary mechanism for toxicity, this is the first time VX has been shown to directly interfere with energy metabolism. Taken together, the ABPP work described here suggests the discovery of novel protein-agent interactions, which could be useful for the development of novel diagnostics or potential adjuvant therapeutics.

[Jinghuaweikang gelatin pearls plus proton pump inhibitor-based triple regimen in the treatment of chronic atrophic gastritis with Helicobacter pylori infection: a multicenter, randomized, controlled clinical study].

OBJECTIVE: To observe the efficacy of Jinghuaweikang gelatin pearls plus proton pump inhibitor (PPI)-based triple regimen in the treatment of chronic atrophic gastritis (CAG) patients with Helicobacter pylori (H.pylori) infection. METHODS: For this multicenter, randomized, controlled clinical study, 90 patients of endoscopically confirmed CAG with positive H.pylori ((13)C or (14)C-urea breath test (UBT) or rapid urease test) were enrolled. There were 46 males and 44 females with an age range of (54 ± 10) years. None of them had H.pylori eradication background. They were randomly divided into 2 groups, Group LACJ (n = 45) received lansoprazole 30 mg+amoxicillin 1000 mg+clarithromycin 500 mg + jinghuaweikang gelatin pearls 240 mg, twice daily, for 10 days (d1-10) plus another 14 days (d11-24) only with jinghuaweikang gelatin pearls 240 mg, twice daily. Group LACB (n = 45) had standard quadruple regimen treatment: lansoprazole 30 mg+amoxicillin 1000 mg+clarithromycin 500 mg+bismuth potassium citrate 220 mg, twice daily for 10 days (d1-10). The status of H.pylori was detected by (13)C-UBT at least 28 days after therapy. RESULTS: The eradication rates in Groups LACJ and LACB were as follows: per-protocol (PP): 70.5% (31/44) and 83.3% (35/42), intention-to-treat (ITT): 68.9% (31/45) and 77.8% (35/45) (both P > 0.05). The symptomatic improvements of bloating in upper abdomen, belching and epigastric pain after treatment in both groups. And those in Group LACJ was higher than those of Group LACB, but no statistical difference existed between two groups (all P > 0.05). CONCLUSIONS: The efficacy of LACJ for the treatment of CAG patients with H.pylori infection is similar to LACB. And the symptomatic improvement of patients is better than LACB.

[Jinghuaweikang capsules combined with triple therapy in the treatment of Helicobacter pylori associated gastritis and duodenal ulcer and analysis of antibiotic resistance: a multicenter, randomized, controlled, clinical study].

OBJECTIVE: To explore the efficacy of Jinghuaweikang capsules plus triple therapy (LACJ) in treatment of Helicobacter pylori (H. pylori) associated gastritis or duodenal ulcer, compare it with bismuth-containing quadruple therapy (LACB) and standard triple therapy (LAC) and analyze the antibiotic sensitivity of gastric mucosal H. pylori strains from the failed patients. METHODS: A total of 565 patients with H. pylori infection were recruited from 11 hospitals from January 2010 to June 2011. There were 336 males and 229 females. They underwent gastroendoscopy examination due to upper gastrointestinal symptoms and had never received H. pylori eradication therapies. Duodenal ulcer patients were divided randomly into LACJ therapy group, LACB therapy group and LAC therapy group while gastritis patients LACJ therapy group and LACB therapy group. Group LAC received lansoprazole 30 mg + amoxicillin 1000 mg + clarithromycin 500 mg, twice a day, for 7 d (d1-7). Group LACJ: LAC therapy plus Jinghuaweikang, 3 capsules, twice a day, for 7 d (d1-7) then Jinghuaweikang, 3 capsules, twice a day, for 14 d (d8-21). Group LACB: LAC plus bismuth potassium citrate 220 mg, twice a day, for 7 d (d1-7) and then bismuth potassium citrate 220 mg, twice a day, for 14 d (d8-21). All duodenal ulcer patients received lansoprazole (30 mg, once a day) for 14 days after the first 7-day of treatment (d 8-21). At least 28 days after the end of treatment, all patients underwent (13)C urea breath test. Gastric mucosa was collected under endoscopy from the failed patients. The detection technique of gene chip was employed to detect antibiotics resistant gene from mucosa. RESULTS: The eradication rates of duodenal ulcer patients in groups LACJ, LACB and LAC were as follows: per-protocol (PP), 80.2% (77/96), 89.9% (89/99) and 72.2% (70/97) (P = 0.007), intention-to-treat (ITT), 78.6% (77/98), 88.1% (89/101) and 70.0% (70/100) (P = 0.007). No statistical differences existed between groups LACJ and LACB or LAC (all P > 0.05). But there were statistical differences between groups LACB and LAC (both P = 0.002). The eradication rates of PP and ITT of chronic gastritis patients in groups LACJ and LACB were as follows: 75.8% (97/128), 74.6% (97/130) vs 83.8% (109/130), 80.1% (109/136) (both P > 0.05). The symptomatic improvements of abdominal pain, burning and acid reflux of duodenal ulcer patients in group LACJ were higher than those in groups LACB and LAC. There were statistical differences between groups LACJ and LAC (all P < 0.05). The symptomatic improvements of bloating and belching for chronic gastritis patients in group LACJ were higher than those of group LACB. But no significant difference existed between two groups (all P > 0.05). Sixty samples of gastric mucosa were collected from the failed patients. The detection rates of antibiotic-resistant gene to clarithromycin and amoxicillin were 60.0% (36/36) and 18.3% (11/60) respectively. CONCLUSIONS: The efficacy of LACJ for the treatment of H. pylori infection patients is similar to LACB and superior to LAC. And the symptomatic improvement of patients is better than the other two regimens. The main cause of treatment failure is antibiotic resistance of H. pylori strains.

[A multicenter study of Chinese patent medicine wenweishu/yangweishu in the treatment of Helicobacter pylori positive patients with chronic gastritis and peptic ulcer].

OBJECTIVE: To evaluate the efficacy of Chinese patent medicine wenweishu /yangweishu in the treatment of Helicobacter pylori (H. pylori) positive patients with chronic gastritis and peptic ulcer. METHODS: A randomized, controlled and multicenter trial was conducted in 642 H. pylori positive patients with chronic gastritis or peptic ulcer. They were randomized to three groups: PCM group (n = 222, pantoprazole 40 mg twice a day, clarithromycin 500 mg twice a day, metronidazole 400 mg twice a day, for 7 days); PCM plus wenweishu group (n = 196); and PCM plus yangweishu group (n = 224). (14)C breath test was performed 4 weeks after therapy. For the patients with gastric ulcer, ulcer healing was determined by endoscopy after therapy. RESULTS: Intention-to-treat H. pylori eradication rate for PCM group, PCM plus wenweishu group, and PCM plus yangweishu group were 57.2% (127/222), 62.2% (122/196), 60.3% (135/224), respectively (P = 0.295, 0.512). Per-protocol H. pylori eradication rates were 62.3% (127/204), 70.1% (122/174), 65.2% (135/207), respectively (P = 0.108, 0.532).Per-protocol analysis gastric ulcer healing rate were 61.9% (13/21) 100.0% (18/18), 86.4% (19/22) respectively. The healing rate in PCM plus wenweishu groups was statistically significantly higher than the rate in PCM group (P = 0.004). The rates of symptom relief in PCM plus wenweishu groups and PCM plus yangweishu were statistically significantly higher than the rate in PCM group (both P < 0.01). Side-effects were rare and comparable between groups. CONCLUSION: Although PCM combined with wenweishu or yangweishu in the treatment of H. pylori positive patients with chronic gastritis and peptic ulcer can not reach a significantly higher eradication rate, it can increase the rates of both gastric ulcer healing and symptom relief.

Effect of TCM treatment according to syndrome differentiation in enhancing curative effect and reducing side-effect of madopa / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effect of TCM treatment according to syndrome differentiation in en-hancing curative effect and reducing side-effect of madopa in patients with Parkinson' s disease (PD).</p><p><b>METHODS</b>The trial was conducted in 101 PD patients with a prospective stratified randomized and controlled method. They were assigned to group 1 in which the patients of rigidity were treated with Pabing Recipe 1 (PR1) plus Madopa tablets, group 2 with those of tremor given Pabing Recipe 3 (PR3) plus Madopa tablets, and group 3 given a fixed Chinese recipe plus Madopa tablets as the control. The treatment course for all the groups was 3 months. Clinical efficacy was evaluated with unified Parkinson's disease rating scale (UPDRS) and the adverse reactions observed before and after treatment.</p><p><b>RESULTS</b>After treatment, the 4 partial scores and the total score of UPDRS decreased significantly in group 2 (P<0.01), and the former of them and the total score declined in group 1 and 3 (P<0.01), the improvement was better in group 1 and 2 than that in group 3 (P<0.01); the improvement rate in group 1 to 3 was 95.5%, 100.0% and 83.7%, respectively, which was significantly higher in group 1 and 2 than that in group 3 (P<0.05).</p><p><b>CONCLUSION</b>TCM treatment according to syndrome differentiation could improve the clinical symptoms and reduce complications in PD patients, which could enhance curative effect and reduce side-effect of madopa.</p>

[Effects of fuzheng yiliu granules on apoptotic rate and mitochondrial membrane potential of hepatocellular carcinoma cell line H22 from mice].

OBJECTIVE: To evaluate the effects of Fuzheng Yiliu Granules (FZYLG) on apoptotic rate and mitochondrial membrane potential (Delta psi m) of hepatocellular carcinoma cell line H22 from mice. METHODS: Forty-eight mice inoculated with H22 cells were randomly divided into four groups: untreated group, cyclophosphamide-treated group, high-dose FZYLG-treated group and low-dose FZYLG-treated group. After 14 days of corresponding treatment, H22 cells in each group were stained with propidium iodide, and the apoptotic rates were detected by flow cytometry (FCM). The rhodamine 123 was used as a fluorescence probe to label the H22 cells, and the fluorescence intensities were observed with laser scanning confocal microscope. The fluorescence intensity of H22 cells indicated the Delta psi m of H22 cells. RESULTS: FZYLG could significantly increase the apoptotic rate while reduce the Delta psi m of H22 cells from mice as compared with those in the untreated group. CONCLUSION: The antitumor effects of FZYLR on H22 cells from mice are related to decreasing the Delta psi m and then inducing the apoptosis of the H22 cells.

A selenoprotein in the plant kingdom. Mass spectrometry confirms that an opal codon (UGA) encodes selenocysteine in Chlamydomonas reinhardtii gluththione peroxidase.

Selenoproteins that contain the rare amino acid selenocysteine in their primary structure have been identified in diverse organisms such as viruses, bacteria, archea, and mammals, but so far not in yeast or plants. Among the most thoroughly investigated families of selenoenzymes are the animal glutathione peroxidases (GPXs). In the last few years, genes encoding GPX-like homologues from Chlamydomonas and higher plants have been isolated, but, unlike the animal ones, all of them have cysteine (rather than selenocysteine) residues in their catalytic site. In all organisms investigated that contain selenoproteins, selenocysteine is encoded by a UGA opal codon, which is usually a stop codon. We report here that, in Chlamydomonas reinhardtii, the cDNA-cloned sequence of a GPX homologue contains an internal TGA codon in frame to the ATG. Specific mRNA expression, protein production, and enzyme activity are selenium-dependent. Sequence analysis of the peptides produced by proteolytic digestion, performed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), confirmed the presence of a selenocysteine residue at the predicted site and suggest its location in the mitochondria. Thus, our data present the first direct proof that a UGA opal codon is decoded in the plant kingdom to incorporate selenocysteine.