Selenium and vitamin B6 cosupplementation improves dyslipidemia and fatty liver syndrome by SIRT1/SREBP-1c pathway in hyperlipidemic Sprague-Dawley rats induced by high-fat diet.

Previously, our group found that the dietary trace mineral element selenium and vitamin B6 (VitB6) alone was involved in lipid metabolism. However, the effects of selenium combined with VitB6 on hyperlipidemia and lipid metabolism have not been reported until now. We hypothesized that selenium and VitB6 cosupplementation would alleviate the hyperlipidemic and hepatic dysfunction and with minimum side effects in a Sprague-Dawley rat model of hyperlipidemia induced by a high-fat diet. Our results showed that selenium combined with VitB6 could improve dyslipidemia and displayed better in vivo hypocholesterolemic abilities at early intervention. Moreover, cosupplementation reduced atherogenic indexes (atherogenic index and atherogenic index of plasm) and the ratio of ApoB/ApoA1. The liver function index aspartate aminotransferase in serum was reduced, as was and total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol in liver. The intervention also increased the levels of ApoA1 in serum and high-density lipoprotein cholesterol of liver. In addition, the combination of selenium and VitB6 decreased liver lipid deposition and alleviated steatosis, reduced adipocyte size of white adipose tissue, increased the activities of hepatic lipase and total lipase and the hepatic 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMGR) level, decreased the hepatic mRNA transcription of lipogenic and regulatory genes including Srebf1 and downstream fat synthesis-related enzymes (Acc and Fasn) and cholesterol synthesis speed limiting enzyme Hmgr, increased the mRNA abundance of Lcat and Cyp7a1, increased the protein expression of SIRT1 and PPARα, and up-regulated the protein expression of sterol regulatory element-binding protein 1c in the livers of hyperlipidemia rats. We first demonstrated that oral selenium and VitB6 cosupplementation exerted synergism in lowering blood and liver lipid profiles and antiatherosclerotic effects in hyperlipidemic rats by reducing endogenous cholesterol and lipid synthesis, enhancing the transport of cholesterol to hepatocytes and promoting fatty acid beta oxidation.

Bioprospecting of endophytic actinobacterium associated with Aloe ferox mill for antibacterial activity.

BACKGROUND: The emergence of drug resistance among pathogens has resulted in renewed interest in bioprospecting for natural microbial products. METHODS: This study aimed to bioprospecting endophytic actinobacterium associated with Aloe ferox Mill for its antibacterial activity. Endophytic actinomycetes were isolated from the gel of A. ferox Mill by surface sterilization technique using actinomycete isolation agar. The isolate with a promising antibacterial activity was identified using 16S rRNA sequence analysis. The minimum inhibitory concentration (MIC) of the extract was assessed by the micro-dilution method and its effect on the respiratory chain dehydrogenase (RCD) activity was ascertained by the iodonitrotetrazolium chloride (INT) assay. Fourier transform-infrared spectrophotometer (FTIR) and gas chromatography-mass spectrophotometry (GC-MS) were employed to identify functional groups and the chemical constituents, respectively. RESULTS: The actinobacterium was found to be Streptomyces olivaceus CP016795.1. Its extract displayed noteworthy antibacterial activity (MIC ≤1 mg/mL) against Staphylococcus aureus (ATCC 25925), Bacillus cereus (ATCC 10102), and Escherichia coli (ATCC 25922); and showed an inhibitory effect on the RCD activity. FTIR spectrum displayed hydroxyl, amine, and aromatic groups, and the GC-MS revealed 5-Hydroxymethylfurfural as the main constituent (19.47%). CONCLUSIONS: S. olivaceus CP016795.1 can serve as a potential source of effective antibacterial compounds.

Protective Effects and Mechanisms of Melatonin on Stress Myocardial Injury in Rats.

ABSTRACT: Prolonged and intense stress can exceed the body's normal self-regulation and limited compensatory and repair capacity, resulting in pathological damage to the body. In this study, we established a rat stress myocardial injury (SMI) model to explore the protective effect of melatonin (MLT) on SMI and its possible mechanisms of action. Adult female Sprague Dawley (SD) rats were randomly divided into 5 groups: blank control group (NC), SMI group, MLT low-dose group, MLT medium-dose group, and MLT high-dose group, and 10 rats in each group were used to establish a SMI model by the water immersion restraint method. We observed the changes in body weight and tail vein glucose of each group. Serum levels of corticosterone (Cort), creatine kinase isoenzyme (CK-MB), and Troponin Ⅰ (Tn-Ⅰ) and activity of lactic acid dehydrogenase were measured by ELISA. Transcriptome sequencing was used to find differentially expressed genes in the control and model groups, and the results were verified by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). HE staining was used to visualize the pathological changes in the heart tissue of each group, and Western blot was used to study the differences in protein expression in the cardiomyocytes of each group to further corroborate the results. The body weight growth rate of rats in the SMI group was significantly lower than that of the NC group ( P < 0.01), and the body weight growth rate of rats in the MLT high-dose group was significantly higher than that of the SMI group ( P < 0.05) with no significant difference compared with the NC group rats. The mean blood glucose of rats in the SMI group was significantly higher compared with the NC group ( P < 0.001), while the mean blood glucose of rats in the MLT administration groups was dose-dependently reduced compared with the SMI group. By RNA-seq and bioinformatics tools such as KEGG and Gene ontology, we found that the circadian clock-related genes Ciart , Arnt1 , Per1 , and Dbp were significantly downregulated in the SMI group during water immersion stress, and differentially expressed genes were enriched in the p38MAPK signaling pathway and p53 signaling pathway. Moreover, genes related to inflammation and apoptosis were differentially expressed. ELISA results showed that Cort, CK-MB, and Tn-Ⅰ levels were significantly higher in the SMI group compared with the NC group ( P < 0.01) and melatonin reduced the levels of Cort, CK-MB, and Tn-Ⅰ and decreased lactic acid dehydrogenase activity in rat serum. HE staining results showed that melatonin could attenuate stress-generated myocardial injury. Western blot showed that melatonin reduced the expression of p38MAPK, p53, Bax, and caspase-3 and increased the expression of Bcl-2 protein in rat heart. Melatonin can inhibit myocardial injury caused by water immersion, and its mechanism of action may be related to the regulation of the expression of circadian clock genes such as Ciart , Arnt1 , Per1 , and Dbp ; the inhibition of the expression of proapoptotic proteins such as p38MAPK, p53, Bax, and caspase-3; and the increase of the expression of Bcl-2 antiapoptotic protein.

Functionalized Mn3 O4 Nanosheets with Photothermal, Photodynamic, and Oxidase-Like Activities Triggered by Low-Powered Near-Infrared Light for Synergetic Combating Multidrug-Resistant Bacterial Infections.

Multidrug-resistant (MDR) pathogenic bacterial infections have become a major danger to public health. Synergetic therapy through multiple approaches is more powerful than the respective one alone, but has been rarely achieved in defeating MDR bacterial infections so far. Herein, indocyanine green-functionalized Mn3 O4 nanosheets are engineered as an efficient and safe antibacterial agent with photothermal, photodynamic, and oxidase-like activities, which display powerful ability in treating MDR bacterial infections. Therein, photothermal and photodynamic activities can be triggered by a single low-powered near-infrared laser (808 nm, 0.33 W cm-2 ), resulting in the generation of localized hyperthermia (photothermal conversion efficiency, 67.5%) and singlet oxygen. Meanwhile, oxidase-like activity of this material further leads to the generation of hydroxyl radical as well as superoxide radical. Sheet-like structure with rough surfaces make them tends to adhere on bacterial surface and thus damage membrane system as well as influence bacterial metabolism. As a result, Gram-positive and Gram-negative bacteria can both be eradicated. Animal experiments further indicate that the functionalized Mn3 O4 nanosheets can effectively treat methicillin-resistant Staphylococcus aureus-infected wounds through the triple synergetic therapy. Moreover, toxicity evaluation in vitro and in vivo has proved the superior biosafety of this material, which is promising to apply in clinical anti-infective therapy.

Restorative effects of red onion (Allium cepa L.) juice on erectile function after-treatment with 5α-reductase inhibitor in rats.

Benign prostatic hyperplasia (BPH) is one of the most prevalent conditions among aged men. The use of 5α-reductase inhibitors (5-ARIs) to treat BPH was linked to erectile dysfunction (ED). Many medicinal plants and secondary metabolites are used in the management of ED. Onion (Allium cepa L.) is an economically affordable vegetable with vital phytochemicals and biological functions. The study aimed to identify the beneficial effects of onion juice on dutasteride (a 5-ARI)-induced ED. Rats were divided into two groups (n = 5 per group): control and dutasteride-treated rats (0.5 mg/kg/day). Dutasteride was administered in drinking water for 12 weeks. Experiments were performed at the end of the 12th week. In vivo erectile responses were measured before and after intracavernosal injection of onion. Relaxant responses to onion juice were examined in the corpus cavernosum (CC). Acetylcholine (ACh)-, electrical field stimulation (EFS)-, sodium nitroprusside (SNP)-induced relaxation responses in CC tissues were evaluated in the absence and presence of onion juice. Total intracavernosal pressure (ICP) and ICP/ mean arterial pressure were significantly reduced in dutasteride-treated rats (1881.14 ± 249.72 mmHg, P < 0.001;0.26 ± 0.03, P < 0.01) as compared to control rats (4542.60 ± 429.19 mmHg, 0.51 ± 0.05), which was normalized after the intracavernous administration of onion (3288.60 ± 185.45 mmHg, 0.58 ± 0.04). Onion markedly induced relaxant responses in control (72.5 ± 4.7) and dutasteride-treated (66.5 ± 2.7) groups after precontraction with phenylephrine. Relaxation responses to onion were partially inhibited after precontraction with KCl (32.5 ± 3.1, P < 0.001). The relaxant responses to ACh (14.9 ± 4.2, P < 0.01) were diminished in dutasteride-treated CC) compared to control CC (59.8 ± 3.4), which was enhanced after the incubation with onion (36.6 ± 4.8). There were no differences in relaxation response to SNP among all groups. However, relaxation response to SNP was reduced in dutasteride-treated CC at 1 µM (P < 0.05) and 10 µM dosages (P < 0.001), which was partially increased after the incubation with onion at 10 µM dosage (P < 0.01). The presence of onion did not change the reduction in EFS-caused relaxation in the dutasteride-treated group. The current data suggest that red onion juice has a restorative effect on erectile function and endothelium-dependent relaxation response following the treatment of dutasteride.

Evaluation of two xenobiotic reductases from Pseudomonas putida for their suitability for magnetic nanoparticle-directed enzyme prodrug therapy as a novel approach to cancer treatment.

Directed enzyme prodrug therapy (DEPT) is a cancer chemotherapy strategy in which bacterial enzymes are delivered to a cancer site before prodrug administration, resulting in prodrug activation at the cancer site and more localized treatment. A major limitation to DEPT is the poor effectiveness of the most studied enzyme for the CB1954 prodrug, NfnB from Escherichia coli, at concentrations suitable for human use. Much research into finding alternative enzymes to NfnB has resulted in the identification of the Xenobiotic reductases, XenA and XenB, which have been shown in the literature to reduce environmentally polluting nitro-compounds. In this study, they were assessed for their potential use in cancer prodrug therapy strategies. Both proteins were cloned into the pET28a+ expression vector to give the genetically modified proteins XenA-his and XenB-his, of which only XenB-his was active when tested with CB1954. XenB-his was further modified to include a cysteine-tag to facilitate direct immobilization on to a gold surface for future magnetic nanoparticle DEPT (MNDEPT) treatments and was named XenB-cys. When tested using high-performance liquid chromatography (HPLC), XenB-his and XenB-cys both demonstrated a preference for reducing CB1954 at the 4-nitro position. Furthermore, XenB-his and XenB-cys successfully induced cell death in SK-OV-3 cells when combined with CB1954. This led to XenB-cys being identified as a promising candidate for use in future MNDEPT treatments.

Peroxisomal Acyl-CoA Oxidase Type 1: Anti-Inflammatory and Anti-Aging Properties with a Special Emphasis on Studies with LPS and Argan Oil as a Model Transposable to Aging.

To clarify appropriateness of current claims for health and wellness virtues of argan oil, studies were conducted in inflammatory states. LPS induces inflammation with reduction of PGC1-α signaling and energy metabolism. Argan oil protected the liver against LPS toxicity and interestingly enough preservation of peroxisomal acyl-CoA oxidase type 1 (ACOX1) activity against depression by LPS. This model of LPS-driven toxicity circumvented by argan oil along with a key anti-inflammatory role attributed to ACOX1 has been here transposed to model aging. This view is consistent with known physiological role of ACOX1 in yielding precursors of specialized proresolving mediators (SPM) and with characteristics of aging and related disorders including reduced PGC1-α function and improvement by strategies rising ACOX1 (via hormonal gut FGF19 and nordihydroguaiaretic acid in metabolic syndrome and diabetes conditions) and SPM (neurodegenerative disorders, atherosclerosis, and stroke). Delay of aging to resolve inflammation results from altered production of SPM, SPM improving most aging disorders. The strategic metabolic place of ACOX1, upstream of SPM biosynthesis, along with ability of ACOX1 preservation/induction and SPM to improve aging-related disorders and known association of aging with drop in ACOX1 and SPM, all converge to conclude that ACOX1 represents a previously unsuspected and currently emerging antiaging protein.

Enzymatic production of bioactive docosahexaenoic acid phenolic ester.

Docosahexaenoic acid (DHA) is increasingly considered for its health benefits. However, its use as functional food ingredient is still limited by its instability. In this work, we developed an efficient and solvent-free bioprocess for the synthesis of a phenolic ester of DHA. A fed-batch process catalyzed by Candida antarctica lipase B was optimised, leading to the production of 440 g/L vanillyl ester (DHA-VE). Structural characterisation of the purified product indicated acylation of the primary OH group of vanillyl alcohol. DHA-VE exhibited a high radical scavenging activity in acellular systems. In vivo experiments showed increased DHA levels in erythrocytes and brain tissues of mice fed DHA-VE-supplemented diet. Moreover, in vitro neuroprotective properties of DHA-VE were demonstrated in rat primary neurons exposed to amyloid-ß oligomers. In conclusion, DHA-VE synergized the main beneficial effects of two common natural biomolecules and therefore appears a promising functional ingredient for food applications.

Bioactive constituents of Spatholobus suberectus in regulating tyrosinase-related proteins and mRNA in HEMn cells.

Spatholobus suberectus Dunn (Leguminosae) is a traditional Chinese herbal medicine used to treat rheumatism, anemia, menoxenia, and other disorders. The extent to which this herbal medicine is useful to skin cells, however, has not been evaluated. Constituents of the 95% ethanol extracts of the dried vine stems of S. suberectus were therefore isolated and examined for their skin-whitening capacity. A bio-guided phytochemical investigation, involving use of the mushroom tyrosinase inhibitory system, of active fractions of the extracts resulted in the isolation of 12 constituents. The structures of these constituents, which were characterized by various spectroscopic techniques, consisted of one flavone, three isoflavones, five flavanones, two flavanonols, and one chalcone. Of these constituents 3',4',7-trihydroxyflavone (1), eriodictyol (3), plathymenin (5), dihydroquercetin (6), butin (7), neoisoliquiritigenin (8), dihydrokaempferol (9), liquiritigenin (10), and 6-methoxyeriodictyol (12) represented compounds isolated for the first time from S. suberectus. These constituents were evaluated their ability to inhibit cellular tyrosinase activity and for their melanin inhibitory activity in human epidermal melanocytes (HEMn). Butin (7) was the most efficacious of these constituents and exhibited concentration-dependent effects. Western blot analysis revealed that expression of tyrosinase and tyrosinase-related proteins 1 and 2 (TRP1 and TRP2) was decreased in butin (7)-treated HEMn cells. Additionally, quantitative real-time PCR (qRT-PCR) analysis disclosed that expression of mRNAs for tyrosinase, TRP1 and TRP2 was suppressed by butin (7). It is concluded that butin (7) is the most active of the components of S. suberectus in inhibiting pigmentation and that this inhibition is exerted through inhibition of transcription of the genes encoding tyrosinase, TRP1 and TRP2.

Genome-wide expression profiling reveals genes associated with amphotericin B and fluconazole resistance in experimentally induced antifungal resistant isolates of Candida albicans.

OBJECTIVES: The aim of this study was to identify changes in the gene expression profile of Candida albicans associated with the acquisition of experimentally induced resistance to amphotericin B and fluconazole. METHODS: C. albicans SC5314 was passed in increasing concentrations of amphotericin B to generate isolate SC5314-AR. Susceptibility testing by Etest revealed SC5314-AR to be highly resistant to both amphotericin B and fluconazole. The gene expression profile of SC5314-AR was compared with that of SC5314 using DNA microarray analysis. Sterol composition was determined for both strains. RESULTS: Upon examination of MICs of antifungal compounds, it was found that SC5314-AR was resistant to both amphotericin B and fluconazole. By microarray analysis a total of 134 genes were found to be differentially expressed, that is up-regulated or down-regulated by at least 50%, in SC5314-AR. In addition to the cell stress genes DDR48 and RTA2, the ergosterol biosynthesis genes ERG5, ERG6 and ERG25 were up-regulated. Several histone genes, protein synthesis genes and energy generation genes were down-regulated. Sterol analysis revealed the prevalence of sterol intermediates eburicol and lanosterol in SC5314-AR, whereas ergosterol was the predominant sterol in SC5314. CONCLUSION: Along with changes in expression of these ergosterol biosynthesis genes was the accumulation of sterol intermediates in the resistant strain, which would account for the decreased affinity of amphotericin B for membrane sterols and a decreased requirement for lanosterol demethylase activity in membrane sterol production. Furthermore, other genes are implicated as having a potential role in the polyene and azole antifungal resistant phenotype.

Reduction of the phenolic components in olive-mill wastewater by an enzymatic treatment and its impact on durum wheat (Triticum durum Desf.) germinability.

Olive-mill wastewater (OMW), an effluent of olive oil extraction process, is annually produced in huge amounts in olive growing areas. An interesting option for its disposal is the spreading on agricultural land, provided that phytotoxic effects are neutralized. The objective of the present investigation was to evaluate the potential of an enzyme-based treatment in removing OMW phytotoxicity. To this aim, germinability experiments on durum wheat (Triticum durum Desf. cv. Duilio) were conducted in the presence of different dilutions of raw or enzyme-treated OMW. OMW treatment with laccase resulted in a 65% and 86% reduction in total phenols and ortho-diphenols respectively, due their polymerization as revealed by size-exclusion chromatography. Raw OMW exerted a significant concentration-dependent inhibition on the germinability of durum wheat seeds which was evident up to a dilution rate of 1:8. When the effluent was treated with a fungal laccase, germinability was increased by 57% at a 1:8 dilution and by 94% at a 1:2 dilution, as compared to the same dilutions using untreated OMW. The treatment with laccase also decreased the mean germination time by about 1 day as compared to untreated controls. These results show that germinability inhibition due to OMW can be reduced effectively using fungal laccase, suggesting that phenols are the main determinants of its phytotoxicity.

Pharmacological interventions for the treatment of neonatal jaundice.

In the neonate, hyperbilirubinaemia is usually due to a combination of an increased bilirubin load and decreased bilirubin elimination. Despite an understanding of the enzymatic pathways leading to bilirubin production and elimination, very few pharmacological interventions to prevent hyperbilirubinaemia are utilized and the mainstay of treatment remains phototherapy. Previously studied pharmacological agents such as D-penicillamine, phenobarbital and clofibrate may yet prove useful. Recent clinical trials using metalloporphyrins to inhibit heme catabolism and bilirubin production provides a novel pharmacological intervention for the treatment of neonatal jaundice. The safety and efficacy of these therapies will need to be confirmed prior to widespread use.

Protective action of arachidonic acid against alloxan-induced cytotoxicity and diabetes mellitus.

Previous studies showed that essential fatty acid (EFA) deficiency, conjugated linoleic acid and troglitazone exert a protective effect in animal models of diabetes mellitus. Here we show that alloxan-induced in vitro cytotoxicity and apoptosis in an insulin secreting rat insulinoma, RIN, cells can be prevented by arachidonic acid (AA) and that both cyclo-oxygenase and lipoxygenase inhibitors do not block this protective action. Alloxan-induced diabetes in male Wistar rats was also prevented by oral supplementation of AA, gamma-linolenic acid (GLA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This protective action is best when the animals were pre-treated with the fatty acid. These results suggest that polyunsaturated fatty acids can prevent alloxan-induced diabetes mellitus in experimental animals and may be useful to prevent diabetes mellitus in the high-risk population.

Effect of ebselen on contractile responses in perfused rabbit basilar artery.

OBJECTIVE: To evaluate the possible role of the antioxidant ebselen in the treatment of cerebral vasospasm, we examined the effects of ebselen on the vasoactive mechanisms induced by endothelin (ET)-1, oxyhemoglobin, and oxygen-derived radicals. METHODS: Isolated rabbit basilar arteries with intact endothelium were fixed in a perfusion system and perfused intraluminally. Contraction of the artery was detected as an increase in perfusion pressure. RESULTS: Ebselen, in a certain concentration range (3 x 10(-6) and 10(-5) mol/L), significantly reduced the contractile response to ET-1 (10(-10) to 10(-8) mol/L) but not the contraction induced by 40 mmol/L potassium. It reduced the contraction induced by 10(-4) mol/L 1,2-dioctanoyl-sn-glycerol, a protein kinase C activator. Addition of 10(-5) mol/L dithiothreitol, a sulfhydryl-reducing agent, partially reversed the inhibitory effects of ebselen on ET-1- and 1,2-dioctanoyl-sn-glycerol-induced contractions. Ebselen (10(-5) mol/L) as well as a combination of catalase (1000 units/mL) and superoxide dismutase (150 units/mL) inhibited the potentiating effects of oxyhemoglobin (10(-5) mol/L) on ET-1-induced contraction. Both ebselen and catalase inhibited the contractile response to hydroxyl radical generated by ferrous ion (10(-3) mol/L) plus hydrogen peroxide (10(-2) mol/L). Ebselen reduced the response to potassium when a high dose (3 x 10(-5) mol/L) was applied and failed to preserve contractility of the preparation after exposure to hydroxyl radical. CONCLUSION: Ebselen suppressed ET-1-induced contraction and synergetic interaction between oxyhemoglobin and ET-1, where free radical formation was involved. These effects may result from modification of the intracellular regulatory system including protein kinase C, as well as from protection against free radicals.